Torque wrench
US4079639A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 6, 1976 |
| Grant date | Mar 21, 1978 |
| Priority date | — |
| Expiry date | Oct 6, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B23/1427
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A torque wrench of the "break" type in which the handle moves relative to the workhead when the preselected tension has been reached, thereby providing a signal which can be felt by the user. The handle is pivotally connected to the workhead, and a tension control mechanism acts between the handle and workhead to prevent pivotal movement of the handle in one direction relative to the workhead until the preselected tension has been reached. The tension control mechanism is adjustable to allow variation of the "break torque," and includes a lever which is pivotally connected to the workhead and coacts with a reaction member connected to the handle. A spring influenced plunger acts on the lever through a toggle bar to hold the lever in an operative position, at which position the handle is held against pivotal movement relative to the workhead, and the toggle bar has its longitudinal axis at an angle to the longitudinal axis of the plunger. When the preselected tension is reached the lever swings about its pivot causing the toggle bar to move closer towards axial alignment with the plunger thereby reducing resistance to pivotal movement of the handle relative to the workhead. Adjustme…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.