Patent ID: 9303735
Filing Date: 2016-04-05
CPC Classification: F16H

Claim Text:
1. A chain tensioner comprising: a tensioner body having a cylindrical plunger bore with an open end; a cylindrical plunger slidable within the plunger bore; and an urging unit accommodated inside an oil pressure chamber formed between the plunger bore and a rear end of the plunger such as to be able to expand and contract and to urge the plunger outward, the plunger including a plunger body, and a check valve and a reserve tube provided inside the plunger body, and the reserve tube having an oil hole provided on one side closer to the check valve and an oil reservoir chamber communicating with the oil pressure chamber through the oil hole, and a connection/adjustment groove formed at least in one of an outer circumferential surface of the plunger body and an inner circumferential surface of the plunger bore to form an oil supply chamber; an oil supply hole formed in the tensioner body, for supplying oil to the supply chamber; an internal supply cavity formed between an outer circumferential surface of a small-diameter part of the reserve tube and an inner circumferential surface of the plunger body; a plunger hole formed in the plunger body, for supplying oil from the supply chamber to the internal supply cavity; and an oil communication notch formed at a distal end in an outward direction of the plunger of the reserve tube, for supplying oil from the internal supply cavity to the oil reservoir chamber.