OUTBOARD MOTOR AND BOAT

Abstract

An outboard motor includes a drive source, a propeller, a propeller shaft extending in a first direction and rotatable together with the propeller, and a transmission shifter to transmit a drive power of the drive source to the propeller shaft. The transmission shifter includes a first assembly including an input shaft rotatable by the drive power of the drive source, a second assembly positioned around a second virtual axis, a gear transmission to transmit power between the first assembly and the second assembly and including a first gear rotatable around the first virtual axis and a second gear to mesh with the first gear and rotatable around the second virtual axis, a winding transmission to transmit power between the first assembly and the second assembly, and a switch to turn on and off the transmission of power between the gear transmission and the winding transmission.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to Japanese Patent Application No. 2023-066310 filed on Apr. 14, 2023. The entire contents of this application are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The technologies disclosed herein relate to outboard motors and boats.

2. Description of the Related Art

A boat is provided with a hull and an outboard motor mounted to a rear portion of the hull. The outboard motor is a device that generates thrust to propel the boat. The outboard motor includes a drive source, a propeller, a propeller shaft that rotates along with the propeller, and a shift device that transmits the drive power of the drive source to the propeller shaft.

There has been disclosed an outboard motor including an engine, a lower gear device for driving a propeller, a transmission device disposed between the engine and the lower gear device, an input shaft that transmits power from the engine to the transmission device, and an output shaft that transmits power from the transmission device to the lower gear device (see, e.g., JP 2018-030458 A). In this prior technology, the transmission device has a forward shaft and a backward shaft. The forward shaft, the backward shaft, and the input shaft and the output shaft, which are coaxially aligned with each other, have a three-shaft configuration in parallel with each other, and each shaft is engaged with gears. Specifically, the input and the output shafts are spaced apart on the same shaft, and the forward and backward shafts are parallel to them. Each shaft is provided with a clutch and an intermediate gear, and the power transmission between the shafts is switched between forward and backward movement.

In the prior art, the input shaft and the output shaft are spaced apart from each other and are arranged in parallel with the forward and backward shafts for switching forward and backward movements separately from the input shaft and the output shaft, so that a clutch and an intermediate gear are arranged on each of the forward and backward shafts, which may increase the size and complexity of the shift device or outboard motor.

SUMMARY OF THE INVENTION

Example embodiments of the present invention disclose technologies that are able to solve the above-mentioned problems.

An outboard motor according to an example embodiment of the present invention includes a drive source, a propeller, a propeller shaft extending in a first direction and rotatable together with the propeller, and a transmission shifter to transmit a drive power of the drive source to the propeller shaft. The transmission shifter includes a first assembly positioned around a first virtual axis that is parallel or substantially parallel to a second direction and includes an input shaft rotatable by the drive power of the drive source, a second assembly positioned around a second virtual axis that is parallel or substantially parallel to the second direction, a gear transmission to transmit power between the first assembly and the second assembly and including a first gear rotatable around the first virtual axis and a second gear that meshes with the first gear and is rotatable around the second virtual axis, a winding transmission to transmit power between the first assembly and the second assembly, and a switch to turn on and off transmission of power between the gear transmission and the winding transmission.

According to this outboard motor, the transmission shifter includes a first assembly positioned around a first virtual axis, a second assembly positioned around a second virtual axis, a gear transmission to transmit power between the first assembly and the second assembly, and a winding transmission to transmit power between the first assembly and the second assembly. Therefore, the switching between forward and backward movements can be performed by the first assembly and the second assembly provided on the input and output shafts without requiring a clutch and intermediate gears arranged on each of the forward and backward shafts to switch forward and backward movements separately from the input shaft and the output shaft.

An outboard motor according to another example embodiment of the present invention includes a drive source, a propeller, a propeller shaft extending in a first direction and rotatable together with the propeller, and a transmission shifter to transmit a drive power of the drive source to the propeller shaft. The transmission shifter includes a first assembly positioned around a first virtual axis that is parallel or substantially parallel to a second direction and including an input shaft rotatable by the drive power of the drive source, a second assembly positioned around a second virtual axis that is parallel or substantially parallel to the second direction, a winding transmission to transmit power between the first assembly and the second assembly, and a switch to turn on and off transmission of power of the winding transmission.

According to this outboard motor, the transmission shifter includes a first assembly positioned around a first virtual axis, a second assembly positioned around a second virtual axis, and a winding transmission to transmit power between the first assembly and the second assembly. Therefore, the switching between forward and backward movements can be performed by the first assembly and the second assembly provided on the input and output shafts without requiring a clutch and intermediate gears arranged on each of the forward and backward shafts to switch forward and backward movements separately from the input shaft and the output shaft.

An outboard motor according to another example embodiment of the present invention includes a drive source, a propeller, a propeller shaft extending in a first direction and rotatable together with the propeller, a transmission shifter to transmit a drive power of the drive source to the propeller shaft, a driven device including a shaft to transmit the drive power of the drive source to the driven device. The transmission shifter includes a first assembly positioned around a first virtual axis that is parallel or substantially parallel to a second direction and includes an input shaft rotatable by the drive power of the drive source, a second assembly positioned around a second virtual axis that is parallel or substantially parallel to the second direction, a gear transmission to transmit power between the first assembly and the second assembly and including a first gear rotatable around the first virtual axis and a second gear that meshes with the first gear and is rotatable around the second virtual axis, a transmission to transmit power between the first assembly and the second assembly and including a third gear rotatable around the first virtual axis and a fourth gear that is spaced apart from the third gear and rotatable around the second virtual axis, and rotates the first assembly and the second assembly in the same direction, and a switch to turn on and off transmission of power between the gear transmission and the transmission. The shaft of the driven device is driven along with the rotation of either or both of the third gear and the fourth gear.

According to this outboard motor, the transmission shifter includes a first assembly positioned around a first virtual axis, a second assembly positioned around a second virtual axis, a gear transmission to transmit power between the first assembly and the second assembly, and a transmission to transmit power between the first assembly and the second assembly to rotate the first assembly and the second assembly in the same direction. Therefore, the switching between forward and backward movements can be performed by the first assembly and the second assembly provided on the input and output shafts without requiring a clutch and intermediate gears arranged on each of the forward and backward shafts to switch forward and backward movements separately from the input shaft and the output shaft. In addition, since the shaft for the driven device is driven along with the rotation of either one or both of the third gear and the fourth gear in the transmission shifter, it is possible to drive the shaft for the driven device without requiring a separate gear device or the like to drive the shaft for the driven device.

The technologies disclosed herein can be implemented in various aspects, including, e.g., outboard motors, boats provided with the outboard motors and hulls, etc.

According to the outboard motors disclosed herein, the transmission shifter includes a first assembly positioned around a first virtual axis, a second assembly positioned around a second virtual axis, and a transmission to transmit power between the first assembly and the second assembly to rotate the first assembly and the second assembly in the same direction. Therefore, the switching between forward and backward movements can be performed by the first assembly and the second assembly provided on the input and output shafts without requiring a clutch and intermediate gears arranged on each of the forward and backward shafts to switch forward and backward movements separately from the input shaft and the output shaft.

The above and other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the example embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically illustrating a configuration of a boat according to a first example embodiment of the present invention.

FIG. 2 is a side view schematically illustrating a configuration of an outboard motor according to the first example embodiment of the present invention.

FIG. 3 is a block diagram illustrating a shift control configuration of the boat.

FIG. 4 is an explanatory view schematically illustrating a power transmission of a transmission shifter in a forward movement state of the boat according to the first example embodiment of the present invention.

FIG. 5 is an explanatory view schematically illustrating the power transmission of the transmission shifter in a backward movement state of the boat according to the first example embodiment of the present invention.

FIG. 6 is an explanatory view schematically illustrating the power transmission of the transmission shifter in a neutral state of the boat according to the first example embodiment of the present invention.

FIG. 7 is a side view schematically illustrating a configuration of an outboard motor according to a second example embodiment of the present invention.

FIG. 8 is an explanatory view schematically illustrating a power transmission of a transmission shifter in a forward movement state of the boat according to the second example embodiment of the present invention.

FIG. 9 is an explanatory view schematically illustrating the power transmission of the transmission shifter in a backward movement state of the boat according to the second example embodiment of the present invention.

FIG. 10 is an explanatory view schematically illustrating the power transmission of the transmission shifter in a neutral state of the boat according to the second example embodiment of the present invention.

FIG. 11 is a side view schematically illustrating a configuration of an outboard motor according to a third example embodiment of the present invention.

FIG. 12 is an explanatory view schematically illustrating a power transmission of a transmission shifter in a forward movement state of the boat according to the third example embodiment of the present invention.

FIG. 13 is an explanatory view schematically illustrating the power transmission of the transmission shifter in a backward movement state of the boat according to the third example embodiment of the present invention.

FIG. 14 is an explanatory view schematically illustrating the power transmission of the transmission shifter in a neutral state of the boat according to the third example embodiment of the present invention.

FIG. 15 is a side view schematically illustrating a configuration of an outboard motor in a modified example embodiment of the present invention.

FIG. 16 is an explanatory view schematically illustrating a configuration around the transmission shifter according to the modified example embodiment.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

FIG. 1 is a perspective view schematically illustrating a configuration of a boat 10 according to the first example embodiment of the present invention. FIG. 1 and the other figures described below show arrows representing each direction with respect to the position of the boat 10. More specifically, each drawing shows arrows representing the front direction (FRONT), rear direction (REAR), left direction (LEFT), right direction (RIGHT), upper direction (UPPER), and lower direction (LOWER), respectively. The front-rear direction, left-right direction, and upper-lower (vertical) direction are perpendicular to each other. It should be noted that, in this specification, axes, members, and the like extending in the front-rear direction need not necessarily be parallel to the front-rear direction. Axes and members extending in the front-rear direction include axes and members that are inclined in the range of ±45° to the front-rear direction. Similarly, axes and members extending in the upper-lower direction include axes and members inclined within a range of ±45° to the upper-lower direction, and axes and members extending in the left-right direction include axes and members inclined within a range of ±45° to the left-right direction.

The boat 10 includes a hull 200 and an outboard motor 100. In this example embodiment, the boat 10 includes only one outboard motor 100, but the boat 10 may include a plurality of outboard motors 100.

The hull 200 is a portion of the boat 10 for occupants to ride. The hull 200 includes a hull main body 202 including a living space 204, a pilot seat 240 installed in the living space 204, and an operating device 250 installed near the pilot seat 240. The operating device 250 steers the boat and includes, e.g., a steering wheel 252, a shift/throttle lever 254, a joystick 255, a monitor 256, and an input device 258. The hull 200 includes a partition wall 220 to partition the rear end of the living space 204 and a transom 210 disposed at the rear end of the hull 200. In the front-rear direction, a space 206 is provided between the transom 210 and the partition wall 220.

FIG. 2 is a side view schematically illustrating a configuration of an outboard motor 100 according to the first example embodiment. The outboard motor 100 in the reference attitude will be described below unless otherwise specified. The reference attitude is an attitude in which the rotation axis Ac of the crankshaft 124, which will be described below, extends in the upper-lower direction and the rotation axis Ap of the propeller shaft 137, which will be described below, extends in the front-rear direction. The front-rear direction, the left-right direction, and the upper-lower direction are respectively defined based on the outboard motor 100 in the reference attitude.

The outboard motor 100 generates thrust to propel the boat 10. The outboard motor 100 is attached to the transom 210 at a rear portion of the hull 200. The outboard motor 100 includes an outboard motor main body 110 and a suspension device 150.

The outboard motor main body 110 includes an engine assembly 120, a transmission 130, a propeller 112, a cowl 114, a casing 116, a water pump 140, and a pump shaft 134.

The cowl 114 is a housing disposed on top of the outboard motor main body 110. The cowl 114 includes an upper cowl 114a defining the upper portion of the cowl 114 and a lower cowl 114b defining the lower portion of the cowl 114. The upper cowl 114a is detachably attached to the lower cowl 114b.

The casing 116 is a housing disposed below the cowl 114 and provided in the lower portion of the outboard motor main body 110. The casing 116 includes a lower case 116b and an upper case 116a. The lower case 116b accommodates at least a portion of the output shaft 133 and the propeller shaft 137 described below. The lower case 116b is connected to the upper case 116a so as to be pivotable around the output shaft 133. The upper case 116a is disposed above the lower case 116b and accommodates a transmission shifter 300.

An engine assembly 120 is accommodated within the cowl 114. The engine assembly 120 includes an engine body 122 and a flywheel magnet generator 127.

The engine body 122 is a prime mover that generates power. The engine body 122 includes, e.g., an internal combustion engine. The engine body 122 includes a crankshaft 124 that converts the reciprocating motion of a piston, not shown, into rotational motion. The crankshaft 124 is arranged in an attitude in which its rotation axis Ac extends in the upper-lower direction. The engine body 122 is an example of a drive source. It should be noted that although the outboard motor 100 of this example embodiment includes the engine body 122, which is an internal combustion engine, as an example of a drive source, the outboard motor 100 may include an electric motor as a drive source or both an internal combustion engine and an electric motor.

The flywheel magnet generator 127 is an alternator as an auxiliary generator for the engine body 122 and is accommodated above the engine body 122 in the cowl 114. The flywheel magnet generator 127 includes a flywheel rotor 128 and a stator 129. The flywheel rotor 128 is connected to the upper end of the crankshaft 124 and rotates along with the rotation of the crankshaft 124.

The transmission 130 transmits the driving force of the engine body 122 to the propeller 112. At least a portion of the transmission 130 is accommodated in the casing 116. The transmission 130 includes a transmission shifter 300 and a propeller shaft 137.

The propeller shaft 137 is a rod-shaped member extending in the front-rear direction and located below the outboard motor main body 110. The propeller shaft 137 rotates along with the propeller 112. The front end of the propeller shaft 137 is accommodated in the lower case 116b, and the rear end of the propeller shaft 137 protrudes rearward from the lower case 116b. The front end of the propeller shaft 137 includes a gear 138.

The transmission shifter 300 transmits the driving force of the engine body 122 to the propeller shaft 137. The transmission shifter 300 is disposed above the output shaft 133.

The operation of the transmission shifter 300, which will be described in detail below, switches the boat 10 between the forward and backward movement states by switching the rotating direction of the propeller shaft 137 to change the rotating direction of the propeller 112.

The propeller 112 is a rotor including a plurality of blades and is attached to the rear end of the propeller shaft 137. The propeller 112 rotates along with the rotation of the propeller shaft 137 around the rotation axis Ap. The propeller 112 generates thrust by rotating. As mentioned above, since the lower case 116b is pivotable, the propeller 112 pivots about the output shaft 133 along with the lower case 116b. Therefore, the boat 10 is steered by pivoting the lower case 116b.

The water pump 140 pumps water from outside the outboard motor 100 to, e.g., cool the engine body 122. The pump shaft 134 extends in an upper-lower direction. The pump shaft 134 is driven by the drive power of the engine body 122 and transmits power to the water pump 140. The water pump 140 is driven by the drive power of the engine body 122 transmitted by the pump shaft 134. The water pump 140 is an example of a driven device. The pump shaft 134 is an example of a shaft for the driven device.

The suspension device 150 connects the outboard motor main body 110 to the hull 200. The suspension device 150 includes a pair of left and right clamp brackets 152, a tilt shaft 160, and a swivel bracket 156.

The pair of left and right clamp brackets 152 are disposed behind the hull 200 in a state separated from each other in the left-right direction and are fixed to the transom 210 of the hull 200 by using, e.g., bolts. Each clamp bracket 152 has a cylindrical supporting portion 152a provided with a through-hole extending in the left-right direction.

The tilt shaft 160 is a rod-shaped member and is rotatably supported within the through-hole in the supporting portion 152a of the clamp bracket 152. The tilt axis At, which is the centerline of the tilt shaft 160, defines a horizontal (left-right) axis in the tilting operation of the outboard motor 100.

The swivel bracket 156 is sandwiched between the pair of clamp brackets 152 and is supported by the supporting portion 152a of the clamp brackets 152 via the tilt shaft 160 so as to be rotatable around the tilt axis At. The swivel bracket 156 is driven to rotate about the tilt axis At with respect to the clamp bracket 152 by a tilt device (not shown) that includes an actuator, such as a hydraulic cylinder, for example.

When the swivel bracket 156 rotates about the tilt axis At with respect to the clamp bracket 152, the outboard motor main body 110 supported by the swivel bracket 156 also rotates about the tilt axis At. This achieves the tilting operation of rotating the outboard motor main body 110 in the upper-lower direction with respect to the hull 200. By this tilting operation, the outboard motor 100 can change the angle of the outboard motor main body 110 around the tilt axis At in the range from the tilt-down state in which the propeller 112 is disposed under the water (the state in which the outboard motor 100 is in the reference attitude) to the tilt-up state in which the propeller 112 is disposed above the water surface. Trimming operation to adjust the attitude of the boat 10 during travel can also be performed by adjusting the angle around the tilt axis At of the outboard motor main body 110.

FIG. 3 is a block diagram illustrating a shift control configuration of the boat 10. The boat 10 includes a controller (control device) 180 and a switch 190.

The controller 180 includes, e.g., a CPU, a multi-core CPU, and a programmable device (field programmable gate array (FPGA), programmable logic device (PLD), and the like).

The switch 190 is included in the transmission shifter 300 and mechanically controls the configuration of various components of the outboard motor 100, such as a first clutch 331 and a second clutch 332 described below, e.g., by hydraulic pressure.

The controller 180 controls the operation of the switch 190 based on the operation of the shift/throttle lever 254 by the crew on the boat 10. The switch 190 operates the first clutch 331 and the second clutch 332 to turn on and off the power transmission of a winding transmission 310 and a gear transmission 320 described below to control the shifting of the boat 10.

FIG. 4 is an explanatory view schematically

illustrating the power transmission of a transmission shifter 300 in the forward movement state of the boat 10 in the first example embodiment. FIG. 5 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300 in the backward movement state of the boat 10 in the first example embodiment. FIG. 6 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300 in the neutral state of the boat 10 in the first example embodiment.

The transmission shifter 300 in the first example embodiment includes a housing 304, a first assembly 301, a second assembly 302, the winding transmission 310, the gear transmission 320, and the switch 190 described above.

The housing 304 is a case that accommodates at least some of the components of the transmission shifter 300.

The first assembly 301 is a collection of components positioned around a first virtual axis VA1 that is parallel to the upper-lower direction. The first assembly 301 includes an input shaft 132, a first clutch 331, a first piston 335, and a first rotor 341. At least some of the components of the first assembly 301 are provided in a first flow path 351 that supplies oil, e.g., hydraulic oil to operate the first piston 335.

The input shaft 132 is a rod-shaped member extending in the upper-lower direction. The upper end of the input shaft 132 is mechanically connected to the lower end of the crankshaft 124 in the engine body 122 and extends downward from the connecting portion with the engine body 122. The input shaft 132 rotates along with the crankshaft 124 under the driving force of the engine body 122.

The first rotor 341 is positioned around the input shaft 132 and rotates around the first virtual axis VA1.

The first clutch 331 and the first piston 335 are positioned around the input shaft 132. The first piston 335 is actuated by hydraulic pressure of the oil supplied through the first flow path 351 to switch the first clutch 331 between engaged and disengaged states. In other words, the first clutch 331 is a hydraulic clutch. By engaging the first clutch 331, the first sprocket 311 described below and the first rotor 341 are connected.

The second assembly 302 is a collection of components positioned around a second virtual axis VA2 that is rearward of the first virtual axis VA1 and parallel to the upper-lower direction. The second assembly 302 includes an output shaft 133, a second clutch 332, and a second piston 336. At least some of the components of the second assembly 302 are provided in a second flow path 352 that supplies oil to operate the second piston 336.

The output shaft 133 is a rod-shaped member that transmits power to the propeller shaft 137. The lower portion of the output shaft 133 protrudes from the housing 304. The lower end of the output shaft 133 includes a gear 135. The output shaft 133 is mechanically connected to the propeller shaft 137 by meshing the gear 135 of the output shaft 133 with the gear 138 of the propeller shaft 137. The output shaft 133 extends upward from the connecting portion with the propeller shaft 137. The output shaft 133 is disposed rearwardly of the input shaft 132 and is spaced apart from the input shaft 132. The output shaft 133 is an example of a second rotor.

The second clutch 332 and the second piston 336 are positioned around the output shaft 133. By engaging the second clutch 332, the second sprocket 312 described below and the output shaft 133 are connected. The second piston 336 is actuated by the hydraulic pressure of the oil supplied through the second flow path 352 to switch the second clutch 332 between engaging state and disengaging state. In other words, the second clutch 332 is a hydraulic clutch.

The gear transmission 320 transmits power between the first assembly 301 and the second assembly 302. The gear transmission 320 includes a first gear 321 and a second gear 322. The first gear 321 and the second gear 322 may be helical gears, for example.

The first gear 321 is attached to the outer circumference of the first rotor 341 and rotates around the first virtual axis VA1 together with the first rotor 341. The second gear 322 is attached to the outer circumference of the output shaft 133, meshes with the first gear 321, and rotates around the second virtual axis VA2 together with the output shaft 133. Since the first gear 321 and the second gear 322 mesh with each other, the rotation of one of the first gear 321 and the second gear 322 causes the rotation of the other of the first gear 321 and the second gear 322. The transmission of power by the gear transmission 320 causes the first assembly 301 and the second assembly 302 to rotate in mutually opposite directions.

The winding transmission 310 is disposed above the gear transmission 320 and transmits power between the first assembly 301 and the second assembly 302. The winding transmission 310 includes a first sprocket 311, a second sprocket 312, and a chain 314. The winding transmission 310 is an example of a transmission. The first sprocket 311 is an example of a third gear. The second sprocket 312 is an example of a fourth gear.

The first sprocket 311 is provided around the input shaft 132. The first sprocket 311 rotates around the first virtual axis VA1 together with the input shaft 132. The second sprocket 312 is provided around the output shaft 133. The second sprocket 312 is spaced apart from the first sprocket 311 and rotates around the second virtual axis VA2 together with the output shaft 133. The chain 314 meshes with both the first sprocket 311 and the second sprocket 312. Because the chain 314 meshes with both the first sprocket 311 and the second sprocket 312, the rotation of one of the first sprocket 311 and the second sprocket 312 causes the rotation of the other of the first sprocket 311 and the second sprocket 312. The transmission of power by the winding transmission 310 causes the first assembly 301 and the second assembly 302 to rotate in the same direction as each other.

With reference to FIG. 4, the power transmission of the transmission shifter 300 during the forward movement of the boat 10 will be explained. The arrows in FIG. 4 indicate the transmission path of the power transmitted from the input shaft 132 (bold arrows) and the rotating direction of each component receiving power from the input shaft 132 (thin arrows).

First, the switch 190 causes the first clutch 331 to be engaged by supplying oil to the first piston 335 via the first flow path 351. By engaging the first clutch 331, the first sprocket 311 and the first rotor 341 are connected. The first sprocket 311 rotates along with the rotation of the input shaft 132. The rotation of the input shaft 132 is transmitted to the first rotor 341 via the first sprocket 311, and the first rotor 341 rotates around the first virtual axis VA1. The rotation of the first rotor 341 causes the first gear 321 to rotate. The rotation of the first gear 321 causes the second gear 322 to rotate, and the rotation of the second gear 322 causes the output shaft 133 to rotate (i.e., the transmission of power from the first assembly 301 to the second assembly 302 by the gear transmission 320 occurs). The rotation of the output shaft 133 is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 forward.

In the forward movement, the switch 190 disengages the second clutch 332. In other words, the second sprocket 312 and the output shaft 133 are disconnected. As a result, even if the first sprocket 311 rotates along with the rotation of the input shaft 132 and the second sprocket 312 is rotated by the chain 314, the rotation of the second sprocket 312 is not transmitted to the output shaft 133. Therefore, transmission of power from the first assembly 301 to the second assembly 302 by the winding transmission 310 does not occur.

With reference to FIG. 5, the power transmission of the transmission shifter 300 during the backward movement of the boat 10 will be explained. The arrows in FIG. 5 indicate the transmission path of the power transmitted from the input shaft 132 (bold arrows) and the rotating direction of each component receiving power from the input shaft 132 (thin arrows).

First, the switch 190 causes the second clutch 332 to be engaged by supplying oil to the second piston 336 via the second flow path 352. By engaging the second clutch 332, the second sprocket 312 and the output shaft 133 are connected. The first sprocket 311 rotates along with the rotation of the input shaft 132. When the rotation of the input shaft 132 is transmitted to the first sprocket 311, the second sprocket 312 is rotated by the chain 314, and the rotation of the second sprocket 312 causes the output shaft 133 to rotate around the second virtual axis VA2 (i.e., the transmission of power from the first assembly 301 to the second assembly 302 by the winding transmission 310 occurs). The rotation of the output shaft 133 is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 backward.

In the backward movement, the switch 190 disengages the first clutch 331. In other words, the first sprocket 311 and the first rotor 341 are disconnected. As a result, even if the first sprocket 311 rotates along with the rotation of the input shaft 132, the rotation of the first sprocket 311 is not transmitted to the first rotor 341. Therefore, transmission of power from the first assembly 301 to the second assembly 302 by the gear transmission 320 does not occur.

With reference to FIG. 6, the power transmission of the transmission shifter 300 in the neutral state of the boat 10 will be explained. The arrows in FIG. 6 indicate the transmission path of the power transmitted from the input shaft 132 (bold arrows) and the rotating direction of each component receiving power from the input shaft 132 (thin arrows).

First, the switch 190 stops supplying oil to the first piston 335 and the second piston 336 to disengage the first clutch 331 and the second clutch 332. By disengaging the first clutch 331, the first sprocket 311 and the first rotor 341 are disconnected. As a result, even if the first sprocket 311 rotates along with the rotation of the input shaft 132, the rotation of the first sprocket 311 is not transmitted to the first rotor 341. Therefore, transmission of power from the first assembly 301 to the second assembly 302 by the gear transmission 320 does not occur. In addition, by disengaging the second clutch 332, the second sprocket 312 and the output shaft 133 are disconnected. As a result, even if the first sprocket 311 rotates along with the rotation of the input shaft 132 and the second sprocket 312 is rotated by the chain 314, the rotation of the second sprocket 312 is not transmitted to the output shaft 133. Therefore, transmission of power from the first assembly 301 to the second assembly 302 by the winding transmission 310 does not occur. Thus, the rotation of the input shaft 132 is not transmitted to the output shaft 133 by either the winding transmission 310 or the gear transmission 320, so that the rotation of the input shaft 132 is not transmitted to the propeller shaft 137.

As explained above, during forward movement of the boat 10, the switch 190 transmits the rotation of the input shaft 132 to the output shaft 133 via the gear transmission 320, which is one of the winding transmission 310 and the gear transmission 320 (i.e., the input shaft 132 and the output shaft 133 rotate in mutually opposite directions). In addition, during backward movement of the boat 10, the switch 190 transmits the rotation of the input shaft 132 to the output shaft 133 via the winding transmission 310, which is the other of the winding transmission 310 and the gear transmission 320 (i.e., the input shaft 132 and the output shaft 133 rotate in the same direction as each other). Furthermore, in the neutral state of the boat 10, the switch 190 does not transmit the rotation of the input shaft 132 to the output shaft 133. The forward, backward, and neutral states of the boat 10 are switched in this manner, thus providing shift control of the boat 10.

In the first example embodiment, the pump shaft 134 is disposed on the first virtual axis VA1. The pump shaft 134 is connected to the input shaft 132 below the input shaft 132 and rotates along with the input shaft 132 and the first sprocket 311. The water pump 140 is disposed below the input shaft 132 and in front of the output shaft 133 (see FIG. 2). In other words, the water pump 140 is disposed in the space defined by the output shaft 133 being offset rearwardly with respect to the input shaft 132, so that the space in the outboard motor 100 can be effectively utilized and an increase in the size of the outboard motor 100 can be prevented. With respect to the water pump 140 disposed below the input shaft 132, it is only required that at least a portion of the water pump 140 is disposed below the lower end of the input shaft 132, and a portion of the water pump 140 may be disposed above a portion of the input shaft 132, or the water pump 140 and the input shaft 132 may be completely separated from each other in the upper-lower direction. In addition, with respect to the water pump 140 disposed forward of the output shaft 133, it is only required that at least a portion of the water pump 140 is disposed forward of the front end of the output shaft 133, and a portion of the water pump 140 may be disposed rearward of a portion of the output shaft 133, or the water pump 140 and the output shaft 133 may be completely separated from each other in the front-rear direction.

FIG. 7 is a side view schematically illustrating a configuration of an outboard motor 100a in the second example embodiment. In the following, the same components of the outboard motor 100a of the second example embodiment as those of the outboard motor 100 of the first example embodiment are designated by the same symbols, and the description of these components is omitted as appropriate. In the outboard motor 100a of the second example embodiment, the transmission shifter 300a and the configuration around the transmission shifter 300a are different from the outboard motor 100 of the first example embodiment.

FIG. 8 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300a in the forward movement state of the boat 10 in the second example embodiment. FIG. 9 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300a in the backward movement state of the boat 10 in the second example embodiment. FIG. 10 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300a in the neutral state of the boat 10 in the second example embodiment.

As with the transmission shifter 300a of the first example embodiment, the transmission shifter 300a of the second example embodiment also includes a first assembly 301a, a second assembly 302a, a winding transmission 310a, a gear transmission 320a, and a switch 190.

In the transmission shifter 300a of the second example embodiment, the configuration of the first assembly 301a is mainly different from the configuration of the first assembly 301 of the first example embodiment. Unlike the first rotor 341 of the first example embodiment, the first rotor 341a of the second example embodiment is disposed below the input shaft 132a. In addition to the configuration of the transmission shifter 300 of the first example embodiment, the first assembly 301a of the second example embodiment further includes a third clutch 333a, a third piston 337a, and a planetary gear device 370a. A third flow path 353a is also provided for oil used to operate the third piston 337a.

The planetary gear device 370a is disposed below the input shaft 132a. The planetary gear device 370a includes an internal gear 371a, a sun gear 372a, a planetary gear 373a, and an engaging portion 374a.

The internal gear 371a is connected to the input shaft 132a and rotates along with the rotation of the input shaft 132a. The sun gear 372a is positioned around the first rotor 341a. The planetary gear 373a includes, e.g., three gears, each of the three gears being disposed between the internal gear 371a and the sun gear 372a. The planetary gear 373a is connected to the first rotor 341a, and the first rotor 341a rotates along with the rotation of the planetary gear 373a around the first virtual axis VA1. The engaging portion 374a is disposed below the sun gear 372a.

The first clutch 331a and the first piston 335a as well as the third clutch 333a and the third piston 337a are positioned around the input shaft 132a. By engaging the first clutch 331a, the sun gear 372a is engaged with the engaging portion 374a. The third piston 337a is actuated by the hydraulic pressure of the oil supplied through the third flow path 353a to switch the third clutch 333a between an engaging state and a disengaging state. In other words, the third clutch 333a is a hydraulic clutch. By engaging the third clutch 333a, the planetary gear 373a is engaged with the sun gear 372a.

With reference to FIG. 8, the power transmission of the transmission shifter 300a during the forward movement of the boat 10 will be explained. The arrows in FIG. 8 indicate the transmission path of the power transmitted from the input shaft 132a (thick arrow) and the rotating direction of each component receiving power from the input shaft 132a (thin arrow). The transmission shifter 300a of the second example embodiment has two forward movement states, a low-speed state and a high-speed state, and these two forward movement states are switched by the switch 190. The low-speed state is an example of a first state, and the high-speed state is an example of a second state.

First, the low-speed state of the two forward movement states will be described. The switch 190 supplies oil to the first piston 335a via the first flow path 351a to cause the first clutch 331a to be engaged. By engaging the first clutch 331a, the sun gear 372a is engaged with the engaging portion 374a. The switch 190 disengages the third clutch 333a by stopping the supply of oil to the third piston 337a. By disengaging the third clutch 333a, the planetary gear 373a is disengaged from the sun gear 372a. The internal gear 371a rotates along with the rotation of the input shaft 132a. As the internal gear 371a rotates, the planetary gear 373a orbits around the sun gear 372a engaged with the engaging portion 374a and transmits the rotation of the input shaft 132a to the first rotor 341a. The first rotor 341a rotates around the first virtual axis VA1. The first gear 321a rotates along with the rotation of the first rotor 341a. The rotation of the first gear 321a causes the second gear 322a to rotate, and the rotation of the second gear 322a causes the output shaft 133a to rotate (i.e., transmission of power from the first assembly 301a to the second assembly 302a by the gear transmission 320a occurs). The rotation of output shaft 133a is transmitted to propeller shaft 137 to generate thrust to move boat 10 forward. The output shaft 133a is an example of a second rotor.

Next, the high-speed state of the two forward movement states will be described. The switch 190 supplies oil to the third piston 337a via the third flow path 353a to cause the third clutch 333a to be engaged. By engaging the third clutch 333a, the planetary gear 373a is engaged with the sun gear 372a. The switch 190 disengages the first clutch 331a by stopping the supply of oil to the first piston 335a. By disengaging the first clutch 331a, the sun gear 372a is disengaged from the engaging portion 374a. The internal gear 371a rotates along with the rotation of the input shaft 132a. As the internal gear 371a rotates, the internal gear 371a, the sun gear 372a, and the planetary gear 373a rotate integrally, and transmits the rotation of the input shaft 132a to the first rotor 341a. The first rotor 341a rotates around the first virtual axis VA1. The rotation of the first gear 321a causes the first rotor 341a to rotate. The rotation of the first gear 321a causes the second gear 322a to rotate, and the rotation of the second gear 322a causes the output shaft 133a to rotate (i.e., the transmission of power from the first assembly 301a to the second assembly 302a by the gear transmission 320a occurs). The rotation of the output shaft 133a is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 forward.

In the forward movement, the switch 190 disengages the second clutch 332a. Thus, the second sprocket 312a and the output shaft 133a are disconnected. As a result, even if the input shaft 132a rotates along with the rotation of the first sprocket 311a and the second sprocket 312a is rotated by the chain 314a, the rotation of the second sprocket 312a is not transmitted to the output shaft 133a. Therefore, transmission of power from the first assembly 301a to the second assembly 302a by the winding transmission 310a does not occur.

With reference to FIG. 9, the power transmission of the transmission shifter 300a during the backward movement of the boat 10 will be explained. The arrows in FIG. 9 indicate the transmission path of the power transmitted from the input shaft 132a (thick arrow) and the rotating direction of each component receiving power from the input shaft 132a (thin arrow). First, the switch 190 supplies oil to the second

piston 336a via the second flow path 352a to cause the second clutch 332a to be engaged. By engaging the second clutch 332a, the second sprocket 312a and the output shaft 133a are connected. The first sprocket 311a rotates along with the rotation of the input shaft 132a. When the rotation of the input shaft 132a is transmitted to the first sprocket 311a, the second sprocket 312a is rotated by the chain 314a, and the output shaft 133a rotates around the second virtual axis VA2 along with the rotation of the second sprocket 312a (i.e., the transmission of power from the first assembly 301a to the second assembly 302a by the winding transmission 310a occurs). The rotation of the output shaft 133a is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 backward.

In the backward movement, the switch 190 disengages the first clutch 331a and the third clutch 333a. Thus, the sun gear 372a is disengaged from the engaging portion 374a and the planetary gear 373a is disengaged from the sun gear 372a. As a result, even if the internal gear 371a rotates along with the rotation of the input shaft 132a, the planetary gear 373a does not orbit around the first virtual axis VA1, so that the rotation of the input shaft 132a is not transmitted to the first rotor 341a. Therefore, transmission of power from the first assembly 301a to the second assembly 302a by the gear transmission 320a does not occur.

With reference to FIG. 10, the power transmission of the transmission shifter 300a in the neutral state of the boat 10 will be explained. The arrows in FIG. 10 indicate the transmission path of the power transmitted from the input shaft 132a (thick arrow) and the rotating direction of each component receiving power from the input shaft 132a (thin arrow).

First, the switch 190 stops supplying oil to the first piston 335a, the second piston 336a, and the third piston 337a to disengage the first clutch 331a, the second clutch 332a, and the third clutch 333a. By disengaging the first clutch 331a and the third clutch 333a, the sun gear 372a is disengaged from the engaging portion 374a and the planetary gear 373a is disengaged from the sun gear 372a. As a result, even if the internal gear 371a rotates along with the rotation of the input shaft 132a, the planetary gear 373a does not orbit around the first virtual axis VA1, so that the rotation of the input shaft 132a is not transmitted to the first rotor 341a. Therefore, transmission of power from the first assembly 301a to the second assembly 302a by the gear transmission 320a does not occur. In addition, by disengaging the second clutch 332a, the second sprocket 312a and the output shaft 133a are disconnected. As a result, even if the first sprocket 311a rotates along with the rotation of the input shaft 132a and the second sprocket 312a is rotated by the chain 314a, the rotation of the second sprocket 312a is not transmitted to the output shaft 133a. Therefore, transmission of power from the first assembly 301a to the second assembly 302a by the winding transmission 310a does not occur. Thus, the rotation of the input shaft 132a is not transmitted to the output shaft 133a, and thus the rotation of the input shaft 132a is not transmitted to the propeller shaft 137.

As explained above, during forward movement of the boat 10, the switch 190 transmits the rotation of the input shaft 132a to the output shaft 133a via the gear transmission 320a, which is one of the winding transmission 310a and the gear transmission 320a (i.e., the input shaft 132a and output shaft 133a rotate in mutually opposite directions). In addition, during backward movement of the boat 10, the switch 190 transmits the rotation of the input shaft 132a to the output shaft 133a via the winding transmission 310a, which is the other of the winding transmission 310a and the gear transmission 320a (i.e., the input shaft 132 and the output shaft 133 rotate in the same direction as each other). Furthermore, in the neutral state of the boat 10, the switch 190 does not transmit the rotation of the input shaft 132a to the output shaft 133a. The forward, backward, and neutral states of the boat 10 are switched in this manner, thus providing shift control of the boat 10.

In the second example embodiment, the power of the input shaft 132a is transmitted to the pump shaft 134a through the gear transmission 325a. Specifically, the driving force of the engine body 122 is transmitted to rotate the second sprocket 312a, which causes the rotation of the gear around the pump shaft 134a, causing the pump shaft 134a to rotate.

FIG. 11 is a side view schematically illustrating a configuration of an outboard motor 100b according to the third example embodiment. In the following, the same components of the outboard motor 100b of the third example embodiment as those of the outboard motor 100a of the second example embodiment are designated by the same symbols, and the description of these components is omitted as appropriate. In the outboard motor 100b of the third example embodiment, the transmission shifter 300b and the configuration around the transmission shifter 300b are different from the outboard motor 100a of the second example embodiment.

FIG. 12 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300b in the forward movement state of the boat 10 in the third example embodiment. FIG. 13 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300b in the backward movement state of the boat 10 in the third example embodiment. FIG. 14 is an explanatory view schematically illustrating the power transmission of the transmission shifter 300b in the neutral state of the boat 10 in the third example embodiment.

As with the transmission shifter 300a of the second example embodiment, the transmission shifter 300b of the third example embodiment also includes a first assembly 301b, a second assembly 302b, a winding transmission 310b, a gear transmission 320b, and a switch 190.

The first assembly 301b of the third example embodiment includes an output shaft 133b in addition to the configuration of the transmission shifter 300a of the second example embodiment. The output shaft 133b is disposed lower than the first rotor 341b. The first gear 321b is provided around the upper end of the output shaft 133b and the lower end of the first rotor 341b. Therefore, the output shaft 133b rotates around the first virtual axis VA1 along with the rotation of the first rotor 341b.

The second assembly 302b of the third example embodiment includes a second rotor 342b instead of the output shaft 133a of the second example embodiment. The second rotor 342b has essentially the same configuration as the output shaft 133a, except that it does not have a gear that meshes with the gear 138 of the propeller shaft 137 and that it is entirely housed in the housing 304b.

Referring to FIG. 12, the power transmission of the transmission shifter 300b during the forward movement of the boat 10 will be described. The arrows in FIG. 12 indicate the transmission path of the power transmitted from the input shaft 132b (thick arrow) and the rotating direction of each component receiving power from the input shaft 132b (thin arrow). As with the transmission shifter 300a of the second example embodiment, the transmission shifter 300b of the third example embodiment also has two forward movement states, a low-speed state and a high-speed state, and these two forward movement states are switched by the switch 190.

First, the low-speed state of the two forward movement states will be described. The switch 190 supplies oil to the first piston 335b via the first flow path 351b to cause the first clutch 331b to be engaged. By engaging the first clutch 331b, the sun gear 372b is engaged with the engaging portion 374b. The switch 190 disengages the third clutch 333b by stopping the supply of oil to the third piston 337b. By disengaging the third clutch 333b, the planetary gear 373b is disengaged from the sun gear 372b. The internal gear 371b rotates along with the rotation of the input shaft 132b. As the internal gear 371b rotates, the planetary gear 373b orbits around the sun gear 372b engaged with the engaging portion 374b and transmits the rotation of the input shaft 132b to the first rotor 341b. The first rotor 341b rotates around the first virtual axis VA1. The rotation of the first rotor 341b causes the first gear 321b to rotate, and the rotation of the first gear 321b causes the output shaft 133b to rotate. The rotation of the output shaft 133b is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 forward.

Next, the high-speed state of the two forward movement states will be described. The switch 190 supplies oil to the third piston 337b via the third flow path 353b to cause the third clutch 333b to be engaged. By engaging the third clutch 333b, the planetary gear 373b is engaged with the sun gear 372b. The switch 190 disengages the first clutch 331b by stopping the supply of oil to the first piston 335b. By disengaging the first clutch 331b, the sun gear 372b is disengaged from the engaging portion 374b. The internal gear 371b rotates along with the rotation of the input shaft 132b. As the internal gear 371b rotates, the internal gear 371b, the sun gear 372b, and the planetary gear 373b rotate integrally, and transmits the rotation of the input shaft 132b to the first rotor 341b. The first rotor 341b rotates around the first virtual axis VA1. The rotation of the first rotor 341b causes the first gear 321b to rotate, and the rotation of the first gear 321b causes the output shaft 133b to rotate. The rotation of the output shaft 133b is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 forward.

In the forward movement, the switch 190 disengages the second clutch 332b. Thus, the second sprocket 312b and the second rotor 342b are disconnected. As a result, even if the first sprocket 311b rotates along with the rotation of the input shaft 132b and the second sprocket 312b is rotated by the chain 314b, the rotation of the second sprocket 312b is not transmitted to the second rotor 342b. Therefore, transmission of power from the first assembly 301b to the second assembly 302b by the winding transmission 310b does not occur, nor does transmission of power from the second assembly 302b to the first assembly 301b by the gear transmission 320b.

With reference to FIG. 13, the power transmission of the transmission shifter 300b during the backward movement of the boat 10 will be explained. The arrows in FIG. 13 indicate the transmission path of the power transmitted from the input shaft 132b and the rotating direction of each component receiving power from the input shaft 132b.

First, the switch 190 supplies oil to the second piston 336b via the second flow path 352b to cause the second clutch 332b to be engaged. By engaging the second clutch 332b, the second sprocket 312b and the second rotor 342b are connected. The first sprocket 311b rotates along with the rotation of the input shaft 132b. When the rotation of the input shaft 132b is transmitted to the first sprocket 311b, the second sprocket 312b is rotated by the chain 314b, and the second rotor 342b rotates around the second virtual axis VA2 along with the rotation of the second sprocket 312b (i.e., transmission of power from the first assembly 301b to the second assembly 302b by the winding transmission 310b occurs). The rotation of the second rotor 342b causes the second gear 322b to rotate, and the rotation of the second gear 322b causes the output shaft 133b to rotate (i.e., transmission of power from the second assembly 302b to the first assembly 301b by the gear transmission 320b occurs). The rotation of the output shaft 133b is transmitted to the propeller shaft 137 to generate thrust to move the boat 10 backward.

In the backward movement, the switch 190 disengages the first clutch 331b and the third clutch 333b. Thus, the sun gear 372b is disengaged from the engaging portion 374b and the planetary gear 373b is disengaged from the sun gear 372b. As a result, even if the internal gear 371b rotates along with rotation of the input shaft 132b, the planetary gear 373b does not orbit around the first virtual axis VA1, so that the rotation of the input shaft 132b is not transmitted to the first rotor 341b nor to the output shaft 133b.

Referring to FIG. 14, the power transmission of the transmission shifter 300b in the neutral state of the boat 10 will be explained. The arrows in FIG. 14 indicate the transmission path of the power transmitted from the input shaft 132b (thick arrow) and the rotating direction of each component receiving power from the input shaft 132b (thin arrow).

First, the switch 190 stops supplying oil to the first piston 335b, the second piston 336b, and the third piston 337b to disengage the first clutch 331b, the second clutch 332b, and the third clutch 333b. By disengaging the first clutch 331b and the third clutch 333b, the sun gear 372b is disengaged from the engaging portion 374b and the planetary gear 373b is disengaged from the sun gear 372b. As a result, even if the internal gear 371b rotates along with the rotation of the input shaft 132b, the planetary gear 373b does not orbit around the first virtual axis VA1, so that the rotation of the input shaft 132b is not transmitted to the first rotor 341b nor to the output shaft 133b. In addition, by disengaging the second clutch 332b, the second sprocket 312b and the second rotor 342b are disconnected. As a result, even if the first sprocket 311b rotates along with the rotation of the input shaft 132b and the second sprocket 312b is rotated by the chain 314b, the rotation of the second sprocket 312b is not transmitted to the second rotor 342b. Therefore, transmission of power from the first assembly 301b to the second assembly 302b by the winding transmission 310b does not occur, nor does transmission of power from the second assembly 302b to the first assembly 301b by the gear transmission 320b. Thus, the rotation of the input shaft 132b is not transmitted to the output shaft 133b, so that the rotation of the output shaft 133b is not transmitted to the propeller shaft 137.

As explained above, in the third example embodiment, during forward movement of the boat 10, the switch 190 transmits the rotation of the input shaft 132b to the output shaft 133b via the first rotor 341b (i.e., the input shaft 132b and the output shaft 133b rotate in the same direction as each other). In addition, during backward movement of the boat 10, the switch 190 transmits the rotation of the input shaft 132b to the output shaft 133b via the second rotor 342b, the gear transmission 320b, and the winding transmission 310b (i.e., the input shaft 132b and the output shaft 133b rotate in mutually opposite directions). The switch 190 does not transmit the rotation of the input shaft 132b to the output shaft 133b in the neutral state. The forward, backward, and neutral states of the boat 10 are switched in this manner, thus providing shift control of the boat 10.

In the third example embodiment, as in the second example embodiment, the driving force of the engine body 122 is transmitted to rotate the second sprocket 312a, which causes the rotation of the gears around the pump shaft 134a, causing the pump shaft 134a to rotate.

The techniques disclosed herein are not limited to the above-described example embodiments and may be modified in various forms without departing from the gist of the present invention, including the following modifications.

FIG. 15 is a side view schematically illustrating a configuration of an outboard motor 100c in a modified example embodiment. In the following, the same components of the outboard motor 100c of the modified example embodiment as those of the outboard motor 100a of the second example embodiment are designated by the same symbols, and the description of these components is omitted as appropriate. In the outboard motor 100c of the modified example embodiment, the transmission shifter 300c and the configuration around the transmission shifter 300c are different from the outboard motor 100a of the second example embodiment.

FIG. 16 is an explanatory view schematically illustrating the configuration around the transmission shifter 300c in the modified example embodiment. The transmission shifter 300c of the modified example embodiment includes a gear transmission 380c instead of the winding transmission 310 provided in the outboard motor 100 of the above example embodiments. The gear transmission 380c includes a third gear 383c, a fourth gear 384c, and a fifth gear 385c. The gear transmission 380c is an example of a transmission.

The third gear 383c is provided around the first assembly 301c and rotates around the first virtual axis VA1. The fourth gear 384c is provided around the second assembly 302c, is spaced apart from the third gear 383c in the front-rear direction, and rotates around the second virtual axis VA2. The fifth gear 385c is disposed between the third gear 383c and the fourth gear 384c and is driven in mesh with one or both of the third gear 383c and the fourth gear 384c.

The power transmission in this modified example embodiment is basically the same as in the above example embodiments, so details are omitted. However, because the fifth gear 385c is disposed between the third gear 383c and the fourth gear 384c, the gear transmission 380c transmits the rotation of the input shaft 132c to the output shaft 133c and rotates the output shaft 133c in the same direction as the input shaft 132c as with the winding transmission 310. The forward, backward, and neutral states of the boat 10 are switched in this manner, thus providing shift control of the boat 10.

The fifth gear 385c in this modified example embodiment is provided around the pump shaft 134c. Therefore, when the driving force of the engine body 122 is transmitted, the fifth gear 385c rotates along with the rotation of both the third gear 383c and the fourth gear 384c causing the pump shaft 134c to rotate. In other words, the gear transmission 380c of this modification can transmit power from the input shaft 132c to the output shaft 133c and from the input shaft 132c to the water pump 140.

The configuration of the boat 10 and the outboard motor 100 of the example embodiments is only an example and may be variously modified. For example, in the above example embodiments, the winding transmission 310 is arranged above the gear transmission 320, but the winding transmission 310 may be arranged below the gear transmission 320.

In the above example embodiments, the second assembly 302 is disposed behind the first assembly 301, but it is not necessary that the second assembly 302 be disposed behind the first assembly 301.

In the above example embodiments, the winding transmission 310 includes two sprockets (the first sprocket 311 and the second sprocket 312) and the chain 314, but a pulley or the like may be used instead of the sprockets, and a belt or the like may be used instead of the chain 314.

In the above example embodiments, the outboard motor 100 is provided with the water pump 140 as a driven device, but it may not be provided with the water pump 140 or may be provided with another driven device instead of the water pump 140.

In the above example embodiments, a multi-disc type clutch is shown as the first clutch 331, the second clutch 332, and the third clutch 333a, but other types of clutches than the multi-disc type may be applied for the first clutch 331, the second clutch 332, and the third clutch 333a. Although the first clutch 331, the second clutch 332, and the third clutch 333a are hydraulic clutches, they may be mechanical clutches such as a wire type, for example.

The first virtual axis VA1 and the second virtual axis VA2 in the above example embodiments are arranged parallel in the upper-lower direction, but need not be strictly parallel to the upper-lower direction. The first virtual axis VA1 and the second virtual axis VA2 may be in any direction as long as they are not perpendicular to the upper-lower direction and may be inclined with respect to the upper-lower direction.

While example embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.

Claims

1. An outboard motor comprising:

a drive source;

a propeller;

a propeller shaft extending in a first direction and rotatable together with the propeller; and

a transmission shifter to transmit a drive power of the drive source to the propeller shaft, the transmission shifter including: a first assembly positioned around a first virtual axis that is parallel or substantially parallel to a second direction, and including an input shaft rotatable by the drive power of the drive source; a second assembly positioned around a second virtual axis that is parallel or substantially parallel to the second direction; a gear transmission to transmit power between the first assembly and the second assembly, and including a first gear rotatable around the first virtual axis and a second gear to mesh with the first gear and rotatable around the second virtual axis; a winding transmission to transmit power between the first assembly and the second assembly; and a switch to turn on and off transmission of power between the gear transmission and the winding transmission.

2. The outboard motor according to claim 1, wherein

the first assembly further includes: a first clutch; and a first rotor to which rotation of the input shaft is transmitted by engaging the first clutch to rotate around the first virtual axis; and

the second assembly includes: a second clutch; and a second rotor to which the rotation the input shaft is transmitted by engaging the second clutch to rotate around the second virtual axis.

3. The outboard motor according to claim 2, wherein the second rotor includes an output shaft that transmits power to the propeller shaft.

4. The outboard motor according to claim 3, wherein the switch is operable to transmit the rotation of the input shaft to the output shaft via one of the gear transmission and the winding transmission by engaging the first clutch, and transmit the rotation of the input shaft to the output shaft via the other of the gear transmission and the winding transmission by engaging the second clutch.

5. The outboard motor according to claim 4, wherein the first clutch and the second clutch are hydraulic clutches.

6. The outboard motor according to claim 3, wherein the first assembly further includes:

a third clutch; and

a planetary gear assembly below the input shaft, the planetary gear assembly including: an internal gear connected to the input shaft; a sun gear; a planetary gear connected to the first rotor and meshing with the sun gear by engaging the third clutch; and an engaging portion engaged with the sun gear by engaging the first clutch.

7. The outboard motor according to claim 6, wherein the switch is operable to switch between:

a first state in which the internal gear rotates along with the rotation of the input shaft by engaging the first clutch, the planetary gear orbits around the sun gear engaged with the engaging portion, and the rotation of the input shaft is transmitted via the first rotor and one of the gear transmission and the winding transmission; and

a second state in which the internal gear rotates along with the rotation of the input shaft by engaging the third clutch, the internal gear, the sun gear, and the planetary gear rotate integrally, and the rotation of the input shaft is transmitted to the output shaft via the first rotor and one of the gear transmission and the winding transmission.

8. The outboard motor according to claim 7, wherein the switch is operable to transmit the rotation of the input shaft to the output shaft via the other of the gear transmission and the winding transmission by engaging the second clutch.

9. The outboard motor according to claim 8, wherein the first clutch, the second clutch, and the third clutch are hydraulic clutches.

10. The outboard motor according to claim 2, further comprising an output shaft rotatable around the first virtual axis along with rotation of the first rotor.

11. The outboard motor according to claim 10, wherein the first assembly further includes:

a third clutch; and

a planetary gear assembly below the input shaft, the planetary gear assembly including: an internal gear connected to the input shaft; a sun gear; a planetary gear connected to the first rotor and meshing with the sun gear by engaging the third clutch; and an engaging portion engaged with the sun gear by engaging the first clutch.

12. The outboard motor according to claim 11, wherein the switch is operable to switch between:

a first state in which the internal gear rotates along with the rotation of the input shaft by engaging the first clutch, the planetary gear orbits around the sun gear engaged with the engaging portion, and the rotation of the input shaft is transmitted to the output shaft via the first rotor; and

a second state in which the internal gear rotates along with the rotation of the input shaft by engaging the third clutch, the internal gear, the sun gear, and the planetary gear rotate integrally, and the rotation of the input shaft is transmitted to the output shaft via the first rotor.

13. The outboard motor according to claim 12, wherein the switch is operable to transmit the rotation of the input shaft to the output shaft via the second rotor, the gear transmission, and the winding transmission by engaging the second clutch.

14. The outboard motor according to claim 13, wherein the first clutch, the second clutch, and the third clutch are hydraulic clutches.

15. The outboard motor according to claim 1, wherein the first gear and the second gear are helical gears.

16. The outboard motor according to claim 1, wherein the winding transmission includes:

a first sprocket positioned around the first assembly;

a second sprocket positioned around the second assembly; and

a chain connecting the first sprocket to the second sprocket.

17. The outboard motor according to claim 3, further comprising:

a driven device to be driven by the drive power of the drive source; wherein

the second assembly is located on one side of the first assembly in the first direction; and

the driven device is located below the input shaft and on another side of the output shaft in the first direction.

18. A boat comprising;

a hull; and

the outboard motor according to claim 1 mounted to a rear of the hull.

19. An outboard motor comprising:

a drive source;

a propeller;

a propeller shaft extending in a first direction and rotatable together with the propeller; and

a transmission shifter to transmit a drive power of the drive source to the propeller shaft, the transmission shifter including: a first assembly positioned around a first virtual axis that is parallel or substantially parallel to a second direction, and including an input shaft rotatable by the drive power of the drive source; a second assembly positioned around a second virtual axis that is parallel or substantially parallel to the second direction; a winding transmission to transmit power between the first assembly and the second assembly; and a switch to turn on and off transmission of power of the winding transmission.

20. A boat comprising;

a hull; and

the outboard motor according to claim 19 mounted to a rear of the hull.

21. An outboard motor comprising:

a drive source;

a propeller;

a propeller shaft extending in a first direction and rotatable together with the propeller; and

a transmission shifter to transmit a drive power of the drive source to the propeller shaft, the transmission shifter including: a first assembly positioned around a first virtual axis that is parallel or substantially parallel to a second direction, and including an input shaft rotatable by the drive power of the drive source; a second assembly positioned around a second virtual axis that is parallel or substantially parallel to the second direction; a gear transmission to transmit power between the first assembly and the second assembly, and including a first gear to rotate around the first virtual axis and a second gear that meshes with the first gear and is rotatable around the second virtual axis; a transmission to transmit power between the first assembly and the second assembly, and including a third gear to rotate around the first virtual axis and a fourth gear that is spaced apart from the third gear and rotatable around the second virtual axis, and that rotates the first assembly and the second assembly in a same direction; a switch to turn on and off transmission of power between the gear transmission and the transmission;

a driven device; and

a shaft to transmit the drive power of the drive source to the driven device and is rotatable along with rotation of either or both of the third gear and the fourth gear.

22. A boat comprising;

a hull; and

the outboard motor according to claim 21 mounted to a rear of the hull.