Tensioner for toothed drive belts
US4708696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1986 |
| Grant date | Nov 24, 1987 |
| Priority date | — |
| Expiry date | Jun 11, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2007/0891
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A tensioner for toothed belts comprises a hydraulic fluid filled cylinder having a piston with a rod projecting out of the cylinder and engaging a pivoted arm with a roller at one end for engaging the belt. A spring within the cylinder urges the rod in the projecting direction, and a check valve carried by the piston allows the rod to project rapidly to take up slack in the belt. Hydraulic fluid, however, flows through the small clearance between the piston and the cylinder wall as the rod retracts, and therefore limits the rate of retraction. A path is provided between seals surrounding the rod to route air directly to the reservoir so that it does not enter the fluid chambers within the cylinder. The piston material is chosen to expand more rapidly than the cylinder with increasing temperatures to reduce variations in leak-down time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.