Abstract: In an actuator having a reversible motor before a step-down gear, this can be optimized kinetically, geometrically and in terms of material engineering when different step-down ratios become active according to the different torque requirement for application and for release, in a manner dependent on direction of rotation, for example of a parking brake operated by an electric motor. For this purpose, two differently dimensioned idler wheels of the step-down gears that mesh, for example, with a stepped motor pinion, act via freewheels acting in opposite directions on a common gear shaft. Depending on direction of rotation of the motor, the gear shaft thereby rotates at different rpms, delivering correspondingly different torques.
Abstract: A circular saw in which cutting speed of a saw blade is smoothly controlled. A speed change mechanism of a circular saw includes first and second rotating shafts disposed parallel to each other, and first and second gear trains having different gear ratios and each having a combination of a drive gear and a driven gear as one unit which are engaged with each other and transmit torque of the first rotating shaft to the second rotating shaft. A torque transmission path via the first gear train is defined as a first power transmission path and a torque transmission path via the second gear train is defined as a second power transmission path, and the transmission path is switched between the first power transmission path and the second power transmission path.
Abstract: A power tool includes a power source, a speed change mechanism and a tool bit. The speed change mechanism includes first and second rotating shafts disposed parallel to each other, a first power transmission path provided with a first gear train and a first clutch and a second power transmission path provided with a second gear train and a second clutch. The power transmission path is switched between the first power transmission path and the second power transmission path while the first and second gear trains are held engaged, by shifting of the first and second clutches between the power transmission state and the power transmission interrupted state according to a load applied to the tool bit. The speed change mechanism further includes a switching retaining mechanism, a switching preventing mechanism, a switching set value adjusting mechanism or a switching mechanism.
Abstract: A mainshaft assembly for a gearbox includes a mainshaft (44) and drive gears (31, 36) carried for rotation about the mainshaft. First and second hubs (50, 50?) are associated with respective drive gears, each hub being operable to selectively couple or uncouple with the drive gear causing it to rotate with the hub or with respect to the hub. A drive connection mechanism (42, 64, 66) associated with each hub selectively connects the hub to the mainshaft. Upon connection of the hubs to the drive gears, the drive connection operates to connect one or other of the hubs to the mainshaft when torque is applied to the mainshaft in a first direction or an opposite direction. This enables a gear ratio to be selected by reversing the torque being handled by the gearbox.
September 23, 2009
Date of Patent:
April 23, 2013
Adrain Paul Moore, Andrew McDougall, Anthony Tremlett, Ian Foster
Abstract: A clutch assembly has a driving assembly and a transmission assembly. The driving assembly has an input axle and at least one driving gear. The transmission assembly is connected to the driving assembly and has an output axle, at least one driven gear, an inner axle and a unidirectional transmitting device. The driven gear is rotatably mounted on the output axle and engages with the driving gear. The inner axle is slidably mounted in the output axle and is engaged with the output axle to rotate with the output axle. The unidirectional transmitting device is mounted in the output to make the inner axle being driven by the at least one driven gear rotate in a unidirectional manner and to provide a clutching effect when the inner axle slides relative to the output axle.
Abstract: An improvement to gear systems, the improved gear system characterized by at least one gear-wheel (42c) provided about a shaft (34), the shaft (34) and the or each gear-wheel (42c) being provided with a actuable engagement therebetween in both rotational and counter-rotational directions (86, 88), such that engagement of the actuable engagement (86, 88) of the or each gear wheel (42c) in both the rotational and counter-rotational directions causes the or each gear-wheel (42c) to rotate in conjunction with the shaft (34) and prevents such from counter-rotating relative to the shaft (34), disengagement of the actuable engagement (86, 88) of the or each gear-wheel (42c) in both the rotational and counter-rotational directions allows the or each gear-wheel (42c) to rotate independently of the shaft (34) and counter-rotate relative to the shaft (34), engagement of the actual engagement (86, 68) in the rotational direction and disengagement of the actual engagement (86, 68) in the counter-rotational direction of th
Abstract: A mechanical transmission (10) includes a first gear (13), a second gear (15), a slip clutch (14), an input shaft (11), a fourth gear (20), a one-way bearing (21), a third gear (18) and an output shaft (12). The first gear (13) and the slip clutch (14) are mounted on the input shaft (11). The first gear (13) is meshed with the second gear (15) which is mounted on the output shaft (12). The one-way bearing (21) and the fourth gear (20) are mounted on the output shaft (12); the latter (20) is meshed with the third gear (18) which is mounted on the input shaft (11) to constitute a step-down gearing (22). When the load upon the output shaft (12) increases so that the torque imposed upon the slip clutch (14) is higher than predetermined, the slip clutch (14) releases, and the increased torque generated by the step-down gear set (18, 20) drives the increased load upon the output shaft (12). Two additional embodiments (10', 10") are disclosed.
Abstract: An automatic transmission for mounting within the rear fork of a bicycle includes a plurality of pairs of constant mesh gears and a plurality of discs. Each disc is concentric with one of the gears in each pair and includes a notch for partially enclosing a centrifugally actuated pawl. The notches in adjacent discs face in opposite directions and all the discs but one include a spring for opposing the centrifugal force on each pawl to keep each pawl in a disengaged position. The one disc includes a spring for holding the pawl in an engaged position. The pawls are shaped to permit the bicycle to coast or freewheel.
Abstract: An automatic transmission is provided for driving a rotating wheel having an axle mounted onto a support frame and especially a bicycle frame. The transmission comprises a power input means such as a dual crank-pedal mechanism attached to the frame for receiving power input along with a drive shaft. A plurality of driving elements are mounted for rotation freely about the drive shaft and have engagement means such as sprockets on the surface thereof, one of the driving elements being a lead driver connected to the drive shaft for driving rotation in one direction along with the drive shaft, the driving elements being located at successively greater distances along the shaft from the axle with the lead driver being the farthest from the axle. A drive plate is coupled to the rotating wheel and has on its surface a plurality of concentrically arranged engagement means such as holes which mate with the sprockets on the driving elements for transmitting rotational power from the drive shaft to the drive plate.
July 31, 1992
Date of Patent:
October 12, 1993
Andrew G. Summerville, Jr., Albert V. Mirto, Jr.
Abstract: A multiple speed ratio power transmission mechanism for an automotive vehicle adapted to be mounted in a transverse position with respect to the fore and aft axis of the vehicle includes a torque input shaft having input gearing fixed thereto. A first countershaft has gearing journalled thereon meshing with the torque input gear and synchronizer clutches adapted to produce a driving connection between the input shaft and the countershaft. A second countershaft has a fifth forward speed gear in meshing engagement with a gear on the input shaft and a synchronizer clutch to produce a driving connection between the input shaft and the second countershaft. A one-way clutch supported on the input shaft produces a one-way driving connection between that shaft and the gear wheel. Rotatably supported on the shaft is a gear that is in continuous meshing engagement with fourth and fifth speed pinions, each pinion carried on one of the countershafts.
Abstract: A vehicular transmission in which a multiple speed manual transmission of the two parallel shaft type has an auxiliary transmission connected in series between the two shafts for some of the multiple speeds. The auxiliary transmission providing a high speed and a low speed. The auxiliary transmission includes gearing for providing the high or low speeds to the gears on one of the shafts. A hydraulic clutch and a one-way clutch in said auxiliary transmission selectively connect the high or low speed gearing, with the one-way clutch engaging when the hydraulic clutch is disengaged and being overrun when the hydraulic clutch is engaged.
Abstract: A power supplying member supplies rotational power in a certain rotational direction to an input member of the transmission, and a power receiving member takes out power from a driven gear wheel shaft. Two driving gear wheel shafts extend parallel to the driven gear wheel shaft. First and second driving gear wheels are respectively rotatably mounted on the first and the second driving gear wheel shaft and meshed with a common driven gear wheel fixedly mounted on the driven gear wheel shaft. First and second synchromesh devices respectively selectively engage the first and the second driving gear wheel to the first and the second driving gear wheel shaft.
Abstract: A speed-changing transmission device for vehicles includes a speed-changing shaft connected to rear wheels and disposed at the rear side of an input shaft driven by an engine co-axially with the input shaft, a counter shaft mounted in parallel with the speed-changing shaft and driven by the input shaft, and forward and backward speed-changing gear systems through which the speed-changing gear is connected to the counter shaft to constitute a speed-changing transmission mechanism. A forward one-way clutch is disposed between the input shaft and the speed-changing shaft of the speed-changing mechanism. In the power transmission path formed by the backward speed-changing gear system, provided is a backward clutch and a backward one-way clutch parallel with the backward clutch. The connection between the engine and the speed-changing the speed is turned into "OFF" state during parking of the vehicle, so that an engine braking effect is obtained to prevent the vehicle from starting naturally.
Abstract: The overdrive transmission for a marine propulsion device includes a first drive gear mounted for common rotation with an input shaft connected to a power source, such as an internal combustion engine, a first driven gear mounted for common rotation with a drive shaft drivingly connected to a propeller shaft carrying a propeller, and one-way, overrunning clutch connecting the input and drive shafts. The first drive gear meshes with a second driven gear having fewer gear teeth than the first drive gear and mounted on a counter shaft for common rotation therewith. The first driven gear meshes with a second drive gear mounted on the counter shaft for rotation relative thereto. The counter shaft is selectively drivingly connected to the second drive gear to drive the drive shaft at a rotational speed higher than that of the input shaft.
Abstract: Disclosed herein is a marine propulsion device including an input shaft drivingly connected to a power source, a lower unit having a rotatably mounted drive shaft extending in coaxial relation to the input shaft, a rotatably mounted propeller shaft carrying a propeller and drivingly connected to the propeller shaft, and a two-speed transmission drivingly connecting the input shaft to the drive shaft. The transmission includes a third shaft rotatably mounted in parallel relation to the input shaft and the drive shaft, a first pair of meshing gears including a first drive gear mounted on the input shaft and a first driven gear mounted on the third shaft, a second pair of meshing gears including a second drive gear mounted on the third shaft and a second driven gear mounted on the drive shaft, and a one-way overrunning clutch drivingly connecting one of the shafts to a gear mounted on the shaft when the rotational speed of the input shaft is less than a predetermined value.