Force entry resistant sash lock
US8789857B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2012 |
| Grant date | Jul 29, 2014 |
| Priority date | — |
| Expiry date | Jul 31, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T292/1056
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An improved forced entry resistant sash lock comprises a housing, a shaft rotatably mounted thereto, a locking spring, and a locking cam and a delay cam rotatably and fixedly mounted to the shaft, respectively. The delay cam selectively engages and drives the locking cam between a locked position and an unlocked position. Locking spring biasing causes engagement with a locking cam opening to lock the cam when in the latch-locked position, with engagement to a depth permitting releasable detent engagement in a delay cam recess. Selective engagement and driving of the locking cam comprises a first portion of delay cam rotation being without driven locking cam rotation, and a second portion causing driven locking cam rotation from a retracted position into a protruding position. Selective engagement is by contact between corresponding protrusions on the delay and locking cams. Shaft/delay cam counter-rotation to unlock the latch proceeds in a reverse manner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.