摘要:
In a sliding mechanism in which one of sliding parts sliding relative to each other is held in a holding portion (4) formed of metal, the sliding part (5) is placed apart from an open end (4c) of an inner wall (4b) of a recessed portion (4a), so that the sliding part is not in contact with the edge (4d) of open end (4c). By this structure, generation of stress concentration on the sliding part can be avoided.
摘要:
In a combination of the shim 5 and cam 1 for use in a reciprocating mechanism portion, the shim 5 is made of a material having a hardness higher than that of the sliding surface of the cam 1 and the sliding surface of the shim 5 is finished to within a range of the surface roughness of R Z 0.07-0.2µm in 10-point mean surface roughness and further the sliding surface of the cam 1 is provided with open pores 1b. In the above combination, the generated torque and the wear of sliding portion are minimized by selecting a shim member whose surface roughness is difficult to deteriorate due to plastic deformation by a injection pump contact with a mating member and corrosion by various impurities mixed in lubricant and the like, and providing the surface of a cam member with an oil film holding function so as to maintain fluid lubrication of the sliding surface.
摘要:
Ce dispositif (10) comporte un arbre à cames (18) sollicitant une tige (20) de la soupape (12) par l'intermédiaire d'un linguet (22) actionné par une came (24). Le linguet (22) comporte une première extrémité d'appui (22A) montée oscillante sur un organe d'appui (26) porté par une face-support (16) du moteur et une seconde extrémité de commande (22B) coopérant avec la tige (20). L'organe d'appui (26) est monté coulissant parallèlement à sa hauteur sur la face-support (16). L'organe d'appui (26) est réglable en hauteur au moyen d'une platine (36) munie d'une rampe (38) de réglage en hauteur coopérant avec une rampe complémentaire ménagée sur l'organe d'appui (26). La platine (36) est immobilisée dans une position de réglage souhaitée à l'aide de moyens (52) comportant, de préférence, une vis de serrage (58).
摘要:
The present invention provides an improved adjusting shim (10) for a valve train in an internal combustion engine for an automobile. The adjusting shim produced from a base material consisting of a ceramic material containing 80 to 98 wt.% of silicon nitride and/or sialon and has a porosity of not more than 3%, a bending strength of not less than 1.0 GPa and an impact compressive elastic limit (Hugoniot elastic limit) of not less than 15 GPa, wherein the base material is provided on the surface thereof which contacts a cam with a ceramic surface layer having a composition different from that of the base material and a hardness lower than that of the base material. The adjusting shim of the present invention enables a power loss of a valve train to be minimized; the abrasion resistance thereof to be improved; and the fuel economy, the performance and durability of an internal combustion engine to be improved.
摘要:
An adjustable valve lash train for an overhead valve engine includes a rocker arm stud (84) having a threaded shank (86) received in a correspondingly threaded bore (88) in said cylinder head (12). The rocker arm stud includes an integral head (94) having a spherically shaped bearing surface (96) on the undersurface thereof in engagement with a correspondingly shaped bearing surface (129) on the rocker arm (82). The head of the rocker arm stud includes a hexagonally shaped recess (98) in the top surface (100) thereof for receipt of an adjustment tool. A threaded jam nut (90) is received about the threaded shank of the rocker arm stud for selectively locking the threaded shank against rotation with respect to the threaded bore of the cylinder head. A push rod guide plate (92) is sandwiched between the cylinder head and the jam nut adjacent the shank of the rocker arm stud for controlling lateral displacement of a push rod (108).