Aisin Seiki Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Kazuharu Yamada

Hisashi Kodama

Katsujiro Sato

Tetsuomi Tamura

Tooru Hamamoto

Toru Hamamoto

A self-contained hydraulic lifter used in valve trains of internal combustion engines having a cylindrical body, a plunger arranged slidably therein, and a diaphragm arranged in the plunger. A metal ring is embedded in the upper portion of the diaphragm and the upper end of the metal ring is in contact with the stopper member fixed to the upper end of the plunger, thereby the sealability of the diaphragm being improved.

Self-contained hydraulic lifter

A self-contained hydraulic lash adjuster having a cup-shaped body and a plunger slidably disposed therein is further provided with a flexible diaphragm secured within a reservoir chamber located in the plunger with one side of said diaphragm being exposed to the atmosphere and the other side being disposed in engagement with the oil supply sealed within the hydraulic lash adjuster. An oil passage is provided in the bottom of the plunger to communicate the reservoir chamber with a pressure chamber defined between the bottom of the plunger and the bottom of the body and a one-way check valve is provided to prevent the return flow of oil through the oil passage to the reservoir. A cup-shaped cover member having apertured side walls is located in the bottom of the plunger over the oil passage to prevent the diaphragm from blocking the oil passage upon deformation of the diaphragm.

Self-contained hydraulic lash adjuster

An oil-containing hydraulic lifter for lash adjustment comprising relatively movable cylinder and plunger members defining a pressure chamber between their closed ends and a reservoir chamber within the plunger. Means are provided for rapid, one-way flow of the oil from the reservoir to the pressure chamber during outward movement of the plunger and for slow, one-way flow from the pressure to the reservoir chamber during inward movement of the plunger. A flexible, bag-shaped diaphragm extending into the reservoir chamber has its open, upper end sealed liquid tightly to the inner wall of the reservoir for sealing in the oil while expanding and collapsing with reciprocation of the plunger. The reservoir chamber has an increased diameter at that part where the diaphragm undergoes most of its expansion and collapse, thereby spacing the inner wall of the reservoir chamber from the diaphragm by a distance great enough to allow full expansion of the diaphragm in the expanding and collapsing operation thereof. The effect is to greatly increase the volumetric change exhibited by the oil within the reservoir chamber during the reciprocation of the plunger, thereby enhancing lash adjusting performance.

Growing community of inventors

Toyota, Japan

Kazuharu Yamada