Abstract: An oil pump comprises a rotation shaft having an eccentric part, a needle roller bearing supporting the eccentric part of the rotation shaft, a tappet abutting on the outer ring of the needle roller bearing and arranged in a radial manner, a plunger arranged on the tappet and reciprocated by the rotation of the rotation shaft, and a balancer arranged on both ends of the eccentric part. The balancer has a large diameter part and a small diameter part and when the large diameter part is arranged so as to face the direction opposite to an eccentric direction, the rolling space of a roller can be projected from an axial direction through the balancer.

Abstract: An oil pump comprises a rotation shaft having an eccentric part, a needle roller bearing supporting the eccentric part of the rotation shaft, a tappet abutting on the outer ring of the needle roller bearing and arranged in a radial manner, a plunger arranged on the tappet and reciprocated by the rotation of the rotation shaft, and a balancer arranged on both ends of the eccentric part. The balancer has a large diameter part and a small diameter part and when the large diameter part is arranged so as to face the direction opposite to an eccentric direction, the rolling space of a roller can be projected from an axial direction through the balancer.

Abstract: The cam follower with roller according to the present invention includes a cam follower body having a roller supporting portion integrally formed therein, a supporting shaft of which both ends are fixed to the roller supporting portion, and a roller rotatably supported to the supporting shaft with a plurality of needle rollers interposed. At least one of the supporting shaft, needle roller and roller is formed of heat-resisting steel, and the both ends of the supporting shaft is caulked to be fixed to the supporting portion.

Abstract: It is aimed to prolong the life of a rocker arm in which rollers are housed in a full type form between a ring and a pin from a viewpoint completely different from the idea of improving the material. It is proposed to suitably control the relation between clearances in circumferential and radial directions for the rollers housed in a roller housing space formed between the outer peripheral surface of the pin and the inner peripheral surface of the ring.

Abstract: It is aimed to prolong the life of a rocker arm in which rollers are housed in a full type form between a ring and a pin from a viewpoint completely different from improvement in the material. It is proposed to suitably control the relation between clearances in circumferential and radial directions for the rollers housed in a roller housing space formed between the outer peripheral surface of the pin and the inner peripheral surface of the ring.