Cam axle underneath type valve mechanism of motorcycle engine

Abstract

The utility model relates to a camshaft-mounted gas distribution mechanism of a motorcycle engine. It includes a camshaft, intake and exhaust ejector rods, intake and exhaust rocker arms and intake and exhaust valves. There is an intake cam and an exhaust cam on the camshaft among the present invention. The intake and exhaust cams respectively push the intake and exhaust push rods through the disc-shaped flat-bottomed intake tappets and exhaust tappets. The axes of the intake and exhaust tappets are all orthogonal to the axis of the camshaft. The cam profiles of the intake and exhaust cams are respectively formed by connecting nine smooth transitional line segments from the beginning to the end. Therefore, the intake and exhaust of the present invention have higher timing accuracy, better continuity in the intake and exhaust process, and will not cause sudden changes in inertial force; the driven part has good force transmission performance and high transmission efficiency. The power and torque of the engine can be increased by 10% to 13%, and the noise can be reduced by about 10dB.

Description

technical field [0001] The invention relates to a gas distribution mechanism of a motorcycle engine, in particular to a camshaft-mounted gas distribution mechanism. Background technique [0002] There are two types of valve trains for motorcycle engines: upper camshaft and lower camshaft. The former engine is commonly called the camshaft-mounted engine, and the latter is commonly called the camshaft-mounted engine (also known as the CG series engine). The former has a relatively simple structure, and it directly pushes the intake and exhaust rocker arms respectively through the intake and exhaust cams on the camshaft to achieve air distribution to the engine cylinders. However, since the upper camshaft is far away from the crankshaft, the driving force must be obtained from the lower crankshaft through a chain drive, so the timing of the gas distribution is poor, resulting in low power, torque and efficiency of the engine . The latter gets the driving force from the crank...

AI Technical Summary

Problems solved by technology

In the case of sharing a cam, either the contour lines of the two cannot meet the design requirements, or the contour line of one of them is sacrificed-at present, most of them are designed according to the intake cam mechanism, that is, the reverse type design, and the exhaust The cam is replaced by the intake cam, so that the opening and closing of the intake and exhaust valves cannot be controlled according to the regular movement during the intake and exhaust process, and the expected timing of gas distribution cannot be realized.

As a result, the power, torque and even efficiency of the existing CG series engines are still low; the valve noise is not easy to control

Images