Abstract: A valve system for driving intake and exhaust valves of an engine has a roller shaft 9 mounted in a recess 5 of a rocker arm body 1 (or a tappet body 21) as a valve system body, a cylindrical bushing 3 rotatably supported by the roller shaft 9, and a roller 2 rotatably supported on the outer periphery of the bushing 3 and opposite a cam 11, in which a lubricating film A is provided on each of the surfaces of sliding contact of the bushing 3 with the roller shaft 9 and with the roller 2, so that the lubricating film A enables the valve system to act smoothly for a long term, without causing loss of the lubricating properties of the slide surfaces 12, 13 of the bushing 3, even in the state of undersupply of an lubricating oil that occurs at the initial stage of operation of the engine.

Abstract: A rocker arm with a roller made with a metal plate and utilized in a valve actuating System of an engine is provided. The roller mounting rocker arm includes a rocker arm body (11) having a pair of side walls (11c) and a connecting portion 12 for connecting the side walls (11c), a roller (7) mounted between the side walls (11c), a pivot engageable recess (12a) formed on the connecting portion by drawing, and a valve stem receiving portion (14) formed at the other end of the side walls (11c). This roller mounting rocker arm has a high rigidity and is suitable for mass-production, and low cost is realized.

Abstract: A rocker arm with a roller made with a metal plate and utilized in a valve actuating system of an engine is provided. The roller mounting rocker arm includes a rocker arm body (11) having a pair of side walls (11c) and a connecting portion 12 for connecting the side walls (11c), a roller (7) mounted between the side walls (11c), a pivot engageable recess (12a) formed on the connecting portion by drawing, and a valve stem receiving portion (14) formed at the other end of the side walls (11c). This roller mounting rocker arm has a high rigidity and is suitable for mass-production, and low cost is realized.