Ball-type tensioner
US8419575B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 2011 |
| Grant date | Apr 16, 2013 |
| Priority date | — |
| Expiry date | Oct 24, 2031 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2007/0859
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A tensioner for a chain or similar power transmission medium comprises a spring-biased plunger having annular rack teeth with gradually sloping forward surfaces and steeper rearward surfaces. The teeth are engaged by radially movable balls received in inclined grooves in an axially movable annular ball seat disposed in an annular groove formed in the wall of a plunger-accommodating hole in a tensioner housing. The bottoms of the inclined grooves face a steep rearward surface of a rack tooth, and the annular ball seat is axially movable in the annular groove and biased in the plunger protruding direction by a spring that exerts a biasing force greater than the biasing force exerted on the plunger. The balls and the movable annular ball seat block retraction of the plunger on engine start-up, but permit retraction when excessive force is imparted to the plunger while the plunger is in a protruding condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.