摘要:
A cam housing 3 in accordance with the present invention includes: a body portion 4 that is provided separately from a cylinder head 1, supports a camshaft 2 for driving a valve 10 provided in the cylinder head 1, and is fixed to the cylinder head 1; a sub housing 20 that includes a mounting concavity 21 for mounting a lash adjuster 18 and is fixed to the body portion 4 with a mounting face 20A thereof forced against an outer face of the body portion 4, the mounting face 20A being different from the face wherein an opening of the mounting concavity 21 is provided; andan air vent 22 that penetrates the sub housing 20 between a wall surface thereof and the mounting face 20A thereof and thereby is provided in the sub housing 20, the wall configuring an inner space formed in the mounting concavity wherein the lash adjuster 18 is mounted.
摘要:
A lash adjuster includes a cylindrical bottomed plunger mounted in a cylindrical bottomed body so as to be movable upward and downward and including a high-pressure chamber defined between an underside of the plunger and a bottom wall of the body to reserve an operating oil, a leak path defined by an inner circumference of the body and an outer circumference of the plunger so that the oil reserved in the high-pressure chamber leaks through the leak path with downward movement of the plunger, and a ring-shaped member located between the inner circumference of the body and the outer circumference of the plunger, normally projecting into the leak path and being elastically deformed radially inward or outward with increase in pressure of the oil at the high-pressure chamber side so as to be retreated from the leak path, thereby reducing flow resistance of the oil in the leak path.
摘要:
A cam housing 3 in accordance with the present invention includes: a body portion 4 that is provided separately from a cylinder head 1, supports a camshaft 2 for driving a valve 10 provided in the cylinder head 1, and is fixed to the cylinder head 1; a sub housing 20 that includes a mounting concavity 21 for mounting a lash adjuster 18 and is fixed to the body portion 4 with a mounting face 20A thereof forced against an outer face of the body portion 4, the mounting face 20A being different from the face wherein an opening of the mounting concavity 21 is provided; and an air vent 22 that penetrates the sub housing 20 between a wall surface thereof and the mounting face 20A thereof and thereby is provided in the sub housing 20, the wall configuring an inner space formed in the mounting concavity wherein the lash adjuster 18 is mounted.
摘要:
A lash adjuster for a valve gear includes a plunger movable upward and downward and including a high-pressure chamber, a leak path defined by an inner circumferential surface of a body and an outer circumferential surface of the plunger so that operating oil reserved in the chamber leaks through the leak path, and a ring-shaped member located between the body and the plunger. The member projects into the leak path during normal operation and is elastically deformed radially inward with increase in oil pressure at the chamber side so as to be retreated from the leak path when abnormal movement occurs in the valve gear such that oil pressure in the chamber exceeds a normal range, thereby reducing flow resistance of the oil in the leak path. The member has a surface receiving oil pressure in the chamber thereby to elastically deform the ring-shaped member radially inward.
摘要:
A cam lobe is formed as a single part, not formed together with a shaft body. The shaft body penetrates through bearing holes, as well as a mounting hole provided in the cam lobe, which is arranged in between adjacent bearing holes. The bearing holes each in a perfect circular shape can be achieved, since there is no need to divide the bearing holes into two semi-circular arc shaped concave portions. Consequently, a camshaft can be supported so as to rotate smoothly.
摘要:
In a process of mounting a camshaft 20 to a supporting member 10, a shaft body 21 is firstly inserted into a first bearing hole 13F in the front side of the supporting member 10, before the shaft body 21 is axially moved toward the second bearing hole 13R. In order to get a cam lobe 22 through a concave bearing portion 13M in a semicircular arc shape, rotation of the camshaft 20 enables a cam nose 22b to be directed downward, which is opposite from the concave bearing portion 13M. This enables avoiding the interference between the cam nose 22b and the concave bearing portion 13M, even when the curvature radius of the concave bearing portion 13M is reduced. Consequently, reduction of the curvature radius of the concave bearing portion 13M achieves the downsizing of the supporting member 10.
摘要:
A helically-shaped intake port comprising a helical portion formed around an intake valve and a substantially straight inlet passage portion tangentially connected to the helical portion. A bypass passage is branched off from the inlet passage portion and connected to the helical portion. A rotary valve is arranged in the bypass passage and actuated by a vacuum operated diaphragm apparatus. The rotary valve is opened when the amount of air fed into the cylinder of an engine is increased beyond a predetermined value. A cooling water passage is arranged beneath and near the bypass passage.
摘要:
A multi-cylinder engine comprising a carburetor housing forming therein at least two branch intake passages. Each of the branch intake passages is connected to a respective intake port. A throttle valve of the carburetor is provided for each cylinder. Each of the throttle valves is arranged in the respective branch intake passage. A single common passage and branch connecting passages which are connected to the common passage are provided. Each of the branch connecting passages opens into the respective intake port in the vicinity of the rear face of the valve head of the corresponding intake valve.
摘要:
A multi-cylinder engine comprising a carburetor housing forming therein at least two branch mixture passages. Each of the branch mixture passages is connected to a respective intake port. A throttle valve of the carburetor is provided for each cylinder. Each of the throttle valves is arranged in the respective branch mixture passage and attached onto a common throttle shaft. A wedge shaped groove is formed on the bottom inner wall of each of the branch mixture passages, and the common throttle shaft is arranged in the wedge shaped groove for causing the mixture to flow only along the upper wall of the branch mixture passage. A single common connecting passage and branch connecting passages which are connected to the common connecting passage are provided. Each of the branch connecting passages opens into the respective intake port in the vicinity of the rear face of the valve head of the corresponding intake valve and is tangentially connected to the inner wall of the corresponding intake port, said wall extending circumferentially about the axis of the corresponding intake valve.
摘要:
A high compression type internal combustion engine comprising a cylinder head having a flat inner wall, and a piston having a flat top face. The flat inner wall and the flat top face form a squish area therebetween. A recess having a lung shaped cross-section is formed in the cylinder head. A shallow groove is formed in the flat inner wall of the cylinder head so as to extend from the intake valve to the recess. The exhaust valve is arranged on the top of the recess. A depression connected to the recess is formed in the shallow groove. The spark plug is arranged in the depression.