Calibration structure for circuit breakers having bimetallic trip member
US6720856B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 2002 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Dec 18, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2071/084
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A thermally compensated circuit breaker has a movable contact assembly (24) which mounts a movable electrical contact (24m) for movement between open and closed contacts positions with a stationary electrical contact (26). The contacts are maintained in the closed circuits position by a latching mechanism (24b, 28g) which prevents opening of the contacts through an opening contacts force provided by a spring (24e). A current carrying trip arm (40a, 44a) deflects upon sufficient I2R heating to transfer motion to the latch to separate the latch (24b) from the latch receiving catch (28g) to trip the circuit breaker. The trip arm (40a, 44a) is part of a pivotably mounted actuator assembly (40, 44) having a movable end portion spaced from the pivot disposed adjacent a motion transfer member (28c). A calibration screw (42a) is located so that the longitudinal axis is in line with a movable end portion of the actuator assembly and the motion transfer member. In one embodiment the head of the calibration screw is captured in a slot in the free end of a calibration base (42d) attached to the trip arm so that deflection of the trip arm directly transfers motion to the motion transfer member …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.