Pneumatic door closer with sustained closing force during closure
US4935989A · kind A · utility
14Cited by
2References
3Claims
0Family size
Inventor
Key dates
| Filing date | May 18, 1989 |
| Grant date | Jun 26, 1990 |
| Priority date | — |
| Expiry date | May 18, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S16/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A door closer is provided of the cylinder/piston type wherein the closer is pivotably mounted to the door at a point adjacent to the piston rod end of the cylinder; a leaf type helper spring may be added between the cylinder and the door; said configuration being capable of providing increased closing force to the door as the door closes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.