Abstract: An internal combustion engine with a hydraulically operated automatic transmission includes a crankcase that is divided on a plane perpendicular to a crankshaft and an outer face of the crankcase in a direction of the crankshaft is covered with a crankcase cover. A transmission gear ratio of the transmission is automatically changed over by control of oil pressures to remove a valve body for readily controlling oil pressures and for raising the accessibility of maintenance.

Abstract: A transmission of an internal combustion engine is used in a saddle-type vehicle (buggy) for running on rough terrain. A crankshaft of the vehicle is arranged so that it is parallel with the traveling direction of the body. The transmission includes a mechanism for switching a gear for forward travel and a gear for backward travel. At least a part of the mechanism for switching the gear for forward travel and the gear for backward travel is provided between a crankcase and a crankcase cover. At least one of shafts forming the switching mechanism is partially overlapped with a main shaft or a counter shaft in the axial direction.

Abstract: An output shaft structure enabling easy and secure positioning of an output shaft for a shaft driven vehicle having an internal combustion engine. The output shaft structure provides first and second cases which mutually connect on a face perpendicular to a crankshaft and form a crankcase, a case cover attached to the outside of the first case and the output shaft arranged in the crankcases and supported by a first bearing provided to the case cover and a second bearing provided to the first case. Also provided is an input gear for the output shaft arranged so that it touches the outside face of the second bearing. Further, the output shaft is provided with a first large diameter part positioned by touching the inside face of the first bearing, and a second large diameter part positioned by touching the outside face of the input gear.

Abstract: In an oil passage structure in a rotary shaft, including two systems of oil passages different in pressure that are provided extending from both ends of the shaft, the rotary shaft is provided with oil supply holes in the radial direction of the shaft for connection between a center hole in the shaft and locations to be supplied with oil. The oil supply holes are bored from the outside of the shaft. At this time, burrs are generated at end portions of the oil supply holes on the side fronting on the center hole. Where the depth of the shaft center hole is a dead end, removal of the burrs is not easy. The shaft center hole is used as an oil passage wherein burrs, if any, in the hole can be easily removed. The two oil passages are in communication with each other through a communication passage smaller than the oil passages in diameter. The smaller-diameter communication passage is closed by pressing a steel ball therein, thereby making both of the oil passages independent from each other.

Abstract: To enhance productivity and maintainability of an internal combustion engine for a vehicle with a torque converter. An internal combustion engine with a torque converter includes a single feed pump for supplying both a working oil for a torque converter and a lubricating oil for the engine with an oil filter in communication with a discharge port of the feed pump being fitted to a crankcase cover. An outlet oil passage of the oil filter is branched into a low-pressure oil passage provided with an orifice and an oil passage for supplying a high-pressure control oil to changeover valves of a transmission. The high-pressure oil passage is provided concentratedly in the crankcase cover.

Abstract: An overhead-valve internal combustion engine with a breather chamber arranged below a camshaft housing chamber for housing the camshaft and formed between a cylinder head and a cylinder block. A driving force transmission chamber is formed between a cylinder and a crankcase. Thus, the discharge of oil from the breather chamber is performed smoothly so as to enhance the vapor-liquid separation performance. A breather inlet passage has an upper end thereof in communication with an inside of a camshaft housing chamber and a lower end thereof in communication with a breather chamber at a position corresponding to a mating face between a cylinder block and a crankcase is formed in the cylinder block such that the breather inlet passage extends vertically. An oil discharge hole is in communication with a lower portion of the inside of the breather chamber and is formed in the crankcase.

Abstract: A compact orifice and an orifice clogging preventing mechanism respectively integrated with a hydraulic control unit in the orifice of a fluid passage of the hydraulic control unit formed by inserting plate between two parts and the orifice clogging preventing mechanism. One groove type fluid passage formed in the first part is in communicate with a groove type fluid passage formed in the second part via a group of small holes formed in a plate. The groove type fluid passage in the second part is in communicate with a separate groove type fluid passage in the first part from the groove type fluid passage in the first part via an orifice formed on the plate and the diameter of each small hole in the group of small holes is set to a smaller value than that of the orifice.

Abstract: A dry-sump lubrication unit for an internal combustion engine for a vehicle. A crankshaft of the vehicle is disposed so as to be parallel with the direction of travel of the vehicle, and in a position offset from a center of the vehicle when viewed from the front or back of the vehicle. A transmission shaft is disposed on the other side thereof. An oil tank is disposed in a crankcase located substantially at the lower center of the crankcase when viewed from the front or back of the vehicle on the rear side with respect to the traveling direction, and/or in a space between the crankcase and a rear case cover. Oil pumps are disposed forwardly of the oil tank. An oil injection pipe extends from the oil tank toward the side surface thereof on the transmission side. The resulting configuration prevents variations in liquid surface of lubricating oil of the vehicle internal combustion engine due to shaking of the vehicle body, and makes it possible to downsize the entire power unit.

Abstract: An engine is disposed with a crankshaft axially oriented in the longitudinal direction of the vehicle body. A camshaft and an exhaust port in a cylinder head are disposed parallel to the crankshaft. The exhaust port is open at the front surface of the cylinder head, and discharges exhaust gases through an exhaust pipe. Hoses extend from a radiator in front of the engine to the front surface of the engine. A valve case is disposed on a left side of a cylinder block in the vicinity of the exhaust port to which the exhaust pipe is connected, and is connected to an air cleaner behind the engine by a substantially straight secondary air pipe.

Abstract: An automatic transmission in a power unit with a torque converter and a hydraulic clutch to be engaged and disengaged for the switching of speed-change gears. Hydraulic pressure is applied to the clutch and is increased only when operating the clutch during acceleration of a vehicle. A pressure control valve is provided at a discharge port of an oil pump for supplying hydraulic oil to the hydraulic clutch. The pressure control valve includes a valve body, a valve element is axially slidably provided in the valve body, and a spring is provided between the valve element and the valve body in a sliding direction of the valve element for adjusting a set pressure for opening/closing of the pressure control valve. The valve element is urged in its closing direction by a repulsive force applied to a stator in the torque converter.

Abstract: In an automatic transmission includes a main shaft and a counter shaft which are parallel to a crankshaft with the rotation of a torque converter on the crankshaft being transmitted to the main shaft through gears. A two-state speed change is conducted by gears provided on the main shaft and the counter shaft. An oil hydraulic clutch is operatively provided for connection and disconnection between the gear for reducing the spacing between the crankshaft and the transmission and to contrive a reduction in size of a power unit. A tubular auxiliary main shaft rotatable relative to the main shaft is provided at the outer circumference of the main shaft with a first-speed drive gear and a rearward-running drive gear are fixed on the auxiliary main shaft. First and second oil hydraulic clutches are provided for enabling contact and separation between the main shaft and the auxiliary main shaft.

Abstract: Many vehicles designed for running on rough terrain include an automatic transmission for performing speed change by connecting or disconnecting an oil hydraulic clutch provided alongside each speed change gear. However, depending on the posture of the driver, it may be impossible to step on the brake. As a result, it may be impossible to achieve creep prevention with a creep preventive mechanism dependent on a brake signal. Therefore, a creep preventive mechanism which operates independently from a brake signal is required. The present invention provides an oil pressure control system operating independently from a brake signal. The system includes an oil pressure supply source with a linear solenoid valve for supplying working oil or interrupting the supply of the working oil to the oil hydraulic clutches. The supply of the working oil to the clutches is interrupted when the vehicle is stopped under an idling condition of an engine.

Abstract: A compact transmission for an internal combustion engine in a saddle ride type vehicle for operating on wasteland that effectively utilizes space and enables members to be laid out freely. A transmission for internal combustion engine, includes a crankshaft disposed in parallel to the operating direction of a vehicle body. A forward-running/backward-running changeover mechanism is provided wherein the supply sources of a working oil and a lubricating oil for an automatic transmission are arranged concentratedly on the side of a front crankcase cover. The changeover mechanism is provided between a rear crankcase and a rear crankcase cover. A forward-running/backward-running changeover shift drum is disposed on the upper side of a plane containing the axis of a main shaft and the axis of a counter shaft of the transmission. One end portion of a shift spindle projects from the rear crankcase cover at a position on a lateral side of the shift drum.

Abstract: A structure is provided for receiving and delivering oil from a first oil path in a wall of a casing to a second oil path within a rotating shaft supported by the casing on an inner side surface of the casing. A recess is formed in which the first oil path is opened. A collar is positioned on an inner peripheral surface of the recess. The collar is fitted in a floating state through an 0-ring. On the inner peripheral surface of the collar an end portion of the rotating shaft is pivotally fitted to open the second oil path within the recess.

Abstract: A four-wheel vehicle for traveling on an irregular road that is superior in weight balance and traveling stability. A rotating section (radial center line L3) of a torque converter T and a drive shaft (longitudinal center line L2) which transmits a driving force from a transmission mechanism M to front or rear wheels, are distributed right and left in an opposed relationship to each other with respect to a longitudinal center line (L1) of a vehicle body.

Abstract: An overhead-valve internal combustion engine with a breather chamber arranged below a camshaft housing chamber for housing the camshaft and formed between a cylinder head and a cylinder block. A driving force transmission chamber is formed between a cylinder and a crankcase. Thus, the discharge of oil from the breather chamber is performed smoothly so as to enhance the vapor-liquid separation performance. A breather inlet passage has an upper end thereof in communication with an inside of a camshaft housing chamber and a lower end thereof in communication with a breather chamber at a position corresponding to a mating face between a cylinder block and a crankcase is formed in the cylinder block such that the breather inlet passage extends vertically. An oil discharge hole is in communication with a lower portion of the inside of the breather chamber and is formed in the crankcase.

Abstract: A hydraulic clutch and a torque converter, a crank web or an alternator provided in separate locations, except opposite positions, for avoiding interference. A crankcase is provided in a transmission for transmitting the revolution of the torque converter to a crankshaft to a main shaft via a gear. Shifting speed in three steps is achieved by a gear provided on the main shaft and a counter shaft and the hydraulic clutch for connecting or disconnecting the gear. One hydraulic clutch is arranged on a main shaft outside a pair of supports for supporting the main shaft, two gears are fixed to the main shaft inside the supports for supporting the main shaft and on both sides close to the support. The two gears engaged with the two gears and hydraulic clutches for connecting or disconnecting each gear are arranged between the two gears.

Abstract: A power transmission apparatus for an engine of a vehicle which can suppress the changing frequency of the ratio of a continuously variable transmission by compensating for driving force upon low speed rotation upon which the torque generated by an engine is low, and can reduce the overall width of the engine to raise the degree of freedom in mounting of the engine to achieve reduction of the cost. A power transmission apparatus for an engine for a vehicle which includes a starting clutch for smoothly connecting rotation of a crankshaft to a transmission upon starting of the vehicle, a hydrostatic continuously variable transmission for performing speed change depending upon a capacity difference between a swash plate hydraulic pump and a swash plate hydraulic motor to transmit rotation of the crankshaft at a reduced speed to a driving wheel, and a slider for moving a ball screw back and forth to change the angle of the swash plate of the swash plate hydraulic motor.

Abstract: A method of manufacturing a ferritic stainless steel sheet having good workability with less anisotropy. The steps include providing a ferritic stainless steel comprising C up to about 0.03 mass %, N up to about 0.03 mass %, Si up to about 2.0 mass %, Mn up to about 2.0 mass %, Ni up to about 0.6 mass %, Cr about 9-35 mass %, Nb about 0.15-0.80 mass % and the balance being Fe except inevitable impurities; precipitation-heating said stainless steel at a temperature in a range of 700-850° C. for a time period not longer than 25 hours; and finish-annealing said stainless steel at a temperature in a range of 900-1100° C. for a time period not longer than 1 minute.

Abstract: To provide a lubricating oil supply structure for an internal combustion engine, which requires no lubricating oil passage to be defined in a crankshaft, is capable of ejecting lubricating oil to a lubrication object, is free of limitations on the layout of the generator and peripheral devices, is capable of cooling generating coils of the generator, and allows the area of the lubrication object to which the lubricating oil is applied to be set with large freedom. A lubricating oil supply structure for an internal combustion engine has a generator having a stator with generating coils and a rotor. A one-way clutch is disposed opposite to the stator across the rotor. The lubricating oil supply structure includes a first nozzle disposed on a stator support of a generator cover for continuously ejecting lubricating oil. The lubricating oil is ejected from the first nozzle to the one-way clutch through holes which are disposed in a position confronting the one-way clutch in an ejected direction.