Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Isamu Takahashi

Yuichi Tawarada

Yoshiki Nagahashi

Kazumitsu Yamamoto

Kei Yoshinaga

Takashi Hasegawa

Michio Asumi

Akira Hayashi

Hirokazu Komuro

Eiko Shiozaki

Masaki Yoneyama

Naoki Kono

Katsuhiro Nakamichi

Katsutaka Hattori

Yutaka Machida

Ken Yamanaka

Toshiharu Akutsu

Yasunobu Hamada

A multi-plate clutch system includes an outer clutch member having a plurality of first clutch plates thereon, a central spool having a plurality of second clutch plates thereon interspaced with the first clutch plates. The clutch system also includes a cam mechanism including a protruding cam and a recessed cam. The protruding cam and the recessed cam respectively include first inclined faces and second inclined faces, which are inclined in the same direction with respect to the circumferential direction. The protruding cam is thus brought into a point contact with the recessed cam during clutch engagement. As such, the multi-plate clutch system can maintain constant variable characteristics of the clutch capacity even when there is a variation in processing accuracy at the time of the production.

Multi-plate clutch system

A dog clutch includes a first engagement face and a second engagement face provided on a surface of a driving rotor and a driven rotor with the two surfaces being opposite each other. The first engagement face engaging with its counterpart when a driving force of the driving members is generated. The second engagement face engaging with its counterpart when the driving member receives the driving force from the driven member. The strength of the engagement portion is balanced reflecting the operational torque changing as a power transmission direction changes. A projection drawing to a plane perpendicular to a rotational axis of a driving rotor and of a driven rotor, the inward extension line of the first engagement face passes through a position offset from the position representing the rotational axis, and the inward extension line of the second engagement face passes through the position representing the rotational axis.

Dog clutch

A clutch for effectively prevents a clutch outer from tilting at the time when torque is varied. The clutch includes damper springs for transmitting, to a clutch outer, torque inputted to a driven gear, and a thrust washer for regulating positional change of a position of the clutch outer with respect to the driven gear in a direction of the shaft axis. The thrust washer is disposed between the driven gear and the clutch outer in an axial direction. The thrust washer is disposed only outward of the damper springs in a radial direction.

Clutch including damper springs

To provide a layout structure of a hydraulic control valve for a valve train in an internal combustion engine which can reduce the influence of heat from the cylinders and can avoid the impairment of the external appearance of the internal combustion engine. An internal combustion engine has a valve operation characteristics changing mechanism that changes the operation characteristics of at least one of an intake valve and an exhaust valve. A hydraulic control valve for a valve train controls the pressure of a hydraulic fluid supplied to the valve operation characteristics changing mechanism. The hydraulic control valve is located on the left side surface of right and left crankcases that support and cover a crankshaft at a position below cylinders.

Layout structure of hydraulic control valve for valve train in internal combustion engine

A lubrication system of a vehicle engine wherein a cylinder head has a head side oil passage disposed at one end thereof along the axis of a crankshaft. A lower case of a crankcase is provided with a supply source side oil passage communicating with an oil supply source and extending parallel to the axis of the crankshaft and a branched oil passage guiding oil to the head side oil passage which branches from the supply source side oil passage and extends upwardly. An upper case side oil passage extending vertically to communicate with a head side oil passage is provided at one end of an upper case along the axis of the crankshaft. A communication passage communicating the upper end of a branched oil passage is provided in a lower case in a position inwardly from the upper case side oil passage along the axis of the crankshaft.

Lubrication system of small vehicle engine

An internal combustion engine in a power unit includes an oil pump that rotates by a transmission mechanism with an endless chain, and a crankcase with an opening formed by protruding walls of side walls of the crankcase in an axial direction. A drive sprocket is fitted to a main shaft of a gear transmission and a driven sprocket is fitted to a shaft end of a drive shaft of an oil pump. When viewed sideways, the protruding walls and mating faces have overlapping parts that partially overlap the driven sprocket. On the other hand, all the shaft end and the remainder of the driven sprocket are exposed inside the opening when the cover is removed. The resulting configuration improves the working efficiency in fitting an oil pump into the crankcase without reducing the rigidity of the crankcase.

Power unit having crankcase to which auxiliary machine is fitted, and motorcycle having power unit

A cooling structure is a separate member from a structural portion of an engine. An oil injection pipe includes cooling oil injection holes for injecting cooling oil into cylinder bores and is mounted across an engine at a somewhat upper position with respect to a crank shaft and in parallel with the crank shaft. Both ends of the oil injection pipe are fixed through mounting members to right and left side walls of the engine, whereby the pipe is mounted. Two left and right pipe portions are joined together at a central position between the two to constitute the oil injection pipe as a single pipe. At the connection in the central position, the oil injection pipe is connected to an oil supply path. Oil supplied through the oil supply path flows into the left and right pipe portions and is injected from the injection holes into the cylinder bores.

Piston cooling device

An improved lubrication structure is provided in an engine by optimizing the structure for recovering scooped oil for enhanced oil recovery efficiency. The oil, which has been scooped up and scattered by the rotation of a clutch, is captured within a concave groove provided within a cylindrical inner surface of a case cover facing the clutch. The captured oil is smoothly guided from the concave groove to an oil receiver of a crankcase via a bent upper edge part of an oil guide plate. The recovered oil passes through dropping holes of a recovered oil path and is supplied to a gear engagement part of a transmission system located below the recovered oil path.

Lubrication system and method, and engine incorporating same

An internal combustion engine includes a crankshaft, a mainshaft, a clutch and a countershaft. The mainshaft is for a transmission and holds a transmission gear train. The clutch is disposed on the extension of the mainshaft. Furthermore, the countershaft for the transmission holds a gear train to mesh with the transmission gear train. Accordingly, power is transmitted in order from the crankshaft to the clutch, the mainshaft, and the countershaft. This arrangement ensures better knee-grip when the internal combustion engine is mounted on a vehicle and improves in-vehicle mountability by reducing the width and the axial length of the internal combustion engine. A mainshaft is disposed about immediately below the crankshaft. At least a part of the mainshaft is provided at the same axial position as the crankshaft.

Internal combustion engine

An automatic centrifugal clutch is arranged at the rear of an engine of a motorcycle, and a belt type continuously variable transmission and a gear type speed reduction device are arranged on opposite sides of the clutch whereby a space at the rear of the engine is effectively utilized, and a space for installing a kick starter is secured externally of the belt type continuously variable transmission. An output shaft of a reduction device and an intermediate shaft of the reduction device are arranged on opposite sides of a plane extending so as to include axes of a crankshaft and an input shaft whereby the longitudinal length of a power transmission device is shortened. An opening of a cooling air discharge passage is provided to face the automatic centrifugal clutch at the front end of the reduction device whereby the automatic centrifugal clutch can be effectively cooled while effectively utilizing the space. Two mating surfaces formed in the case means are offset from each other, whereby the space within the case means can be effectively utilized. Furthermore, a reed valve and a starter motor are arranged with the crankshaft interposed therebetween on a crank case whereby there is secured a space for efficiently arranging an intake system leading to the reed valve.

Growing community of inventors

Saitama, Japan

Isamu Takahashi