Snap-acting thermally-responsive bimetallic actuators
US4507642A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 26, 1983 |
| Grant date | Mar 26, 1985 |
| Priority date | — |
| Expiry date | Jul 26, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2037/5472
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A snap-acting thermally-responsive actuator for an electric switch comprises a pear-shaped dished bimetallic blade having a U-shaped cut-out defining a tongue extending from its root or attached end at the larger end of the pear-shaped blade axially of the blade towards the smaller end of the blade, the tongue extending between outer leg portions of the blade which each have a width which decreases in a direction from the larger towards the smaller end of the blade. When the blade is mounted in a switch with the tip end of its tongue secured to a terminal part of the switch and with a moving switch contact carried on the smaller end of the blade for co-operation with a fixed switch contact secured to another terminal part of the switch, the blade thereby being susceptible to heating by electric current flow through the switch when the switch contacts are closed, the pear-shaped blade configuration coupled with the thinning of the outer legs towards the smaller end of the blade provides improved mechanical switching characteristics and improved self-heating characteristics in the blade leading to improved consistency of operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.