Tensioner
US8277347B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 2007 |
| Grant date | Oct 2, 2012 |
| Priority date | — |
| Expiry date | Jan 17, 2029 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2007/0855
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The present invention is directed to decrease the impact sound of the ratchet mechanism generated at the time of piston retraction. The tensioner includes a piston 3 slidable in the piston bore 2a of the housing 2 and an expandable circlip member 5 engageable with the engagement groove 3a of the piston 3. The piston bore 2a has a guide groove 20 formed therein that has front and rear stop surfaces 20a, 20b adapted to contact the circlip member 5. The engagement groove 3a is formed by a round seat portion S0 that the circlip member 5 is adapted to seat, a piston-retraction restricting portion S0S1 that is formed on the front side of the round scat portion S0 and a piston-advance permitting portion S0S2 that is formed on the front side of the round seat portion S0. The piston-retraction restricting portion S0S1 permits the circlip member 5 to travel a short distance toward the front side along the rear side stop surface 20b to allow for an enlargement of the circlip member 5 and to restrict retraction of the piston 3 when the piston 3 retracts and the circlip member 5 contacts the rear side stop surface 20b of the guide groove 20.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.