Security devices for rotatable members and fluid flow control valves incorporating such devices
US4450697A · kind A · utility
Inventor
Key dates
| Filing date | Sep 10, 1981 |
| Grant date | May 29, 1984 |
| Priority date | — |
| Expiry date | Sep 10, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/7593
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A security device for a rotatable member of a machine element, such as the spindle or nut of a fluid-flow control valve, to prevent the unauthorized operation thereof. A turning member having a cylindrical surface is fitted to the valve spindle and a shroud is rotatably mounted on the member, the shroud having lugs which engage parts of the valve to prevent rotation of the shroud when the device is fitted to the valve. Projections upstand from the cylindrical surface and the turning member can be operated only by a key able to fit within the shroud and over the cylindrical surface, with recesses appropriately positioned to accommodate the projections, such that torque can be imparted to the turning member through the interengagement of at least one projection with a wall of the key defining the associated recess. A locking device including a pin spring-urged out of a bore in the base of the shroud may engage an appropriate recess in the turning member, further to enhance security. Such a lock may only be released by use of the appropriate key, to press the pin downwardly to move free of the turning member. The security device may be modified for use with a rising stem fluid-flow co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.