Yamaha Hatsudoki Kabushiki Kaisha

Toshihiko Takahashi

Kazuya Koike

Yoshihiko Moriya

Masaki Torigoshi

Ryusuke Kato

Yuuji Araki

In a variable valve apparatus, a second connector has a fifth side surface located below a fourth side surface and further away from a second side surface than is the fourth side surface, so that a width in a direction along a rocker shaft is narrower in a lower portion adjacent to an inlet valve than in an upper portion adjacent a slipper surface. A guide surface is provided in a lower portion of the fourth side surface and includes an arc that is shorter than a semicircle, and coaxial and equal in radius with an engaging hole. Thus, even when a connecting pin is advanced in a state of a through-hole and the engaging hole not being in precise alignment, the forward end of the connecting pin is guided through the guide surface into the engaging hole. An extended period can therefore be secured for advancing the connecting pin, to improve the certainty of connection.

Variable valve apparatus, and an engine apparatus and a transport machine having the same

An engine includes a cylinder, an exhaust port, an exhaust valve, a secondary air supply pipe, and an electromagnetic valve. The electromagnetic valve is opened in a predetermined time period after a point in time when a lift amount of the exhaust valve reaches about half a maximum value during a time period in which an opening of the exhaust port is opened. This causes air to be supplied from a secondary air supply pipe to the exhaust port.

Engine and vehicle

A variable valve device is constructed to prevent inclination of a sliding surface of a high speed rocker arm. In an engagement surface where a connecting pin and the engagement portion of a high speed rocker arm are in contact, the center of the width of the surface in the direction of the cam shaft is provided closer to the high speed rocker arm than the center of the width in the direction of the camshaft of a cam contact surface where the high speed cam and the sliding surface of the high speed rocker arm are in contact. The low speed rocker arm includes a cam receiver and a connecting portion. The width of the connecting portion is larger than that of the cam receiver. The side surface of the connecting portion projects beyond the side surface of the cam receiver. The high speed rocker arm includes a cam receiver and a connecting portion. The side surface of the connecting portion and the side surface of the connecting portion are provided in the cam contact surface and within the width of the surface in the direction of the camshaft.

Variable valve device for engine

An engine having a variable valve mechanism arranged to switch a lift degree of a valve between a low speed state and a high speed state includes a cam carrier defined by a cam bearing portion, a rocker shaft support, and a hydraulic cylinder support. The cam bearing portion is provided on a line passing through the bore center of a cylinder in a plane perpendicular or substantially perpendicular to the camshaft. The low speed rocker arm swings in response to the low speed cam of the camshaft. The high speed rocker arm swings in response to the high speed cam of the camshaft. The low speed rocker arm includes a through hole. A connecting pin is slidably inserted into the through hole and urged toward the hydraulic cylinder support. A hydraulic cylinder is provided in the hydraulic cylinder support.

Engine having variable valve mechanism

An exhaust system includes a first exhaust pipe group, a first catalyst device, and a second exhaust pipe group. A first coupling pipe of the first exhaust pipe group includes spaces in communication with respective first exhaust pipes. A second coupling pipe of the second exhaust pipe group includes spaces in communication with respective second exhaust pipes. The first exhaust pipe group and the second exhaust pipe group are joined such that the respective spaces are opposed to one another, with the first catalyst device interposed therebetween.

Growing community of inventors

Shizuoka, Japan

Toshihiko Takahashi