| 摘要 |
<p>An adjustable magnetic trip unit (1) for a circuit breaker includes a torsion spring (33) which applies a bias force to the plunger (15) of a trip solenoid (7). The torsion spring (33) is mounted on a driven bevel gear (47) and wound by an adjustment knob (39) coupled to a driving bevel gear (51) to adjust the current at which the solenoid (7) is activated. An indexer (37) having peripheral flates (61) which engage a seat (55) in the circuit breaker housing (3) provides a pluarlity of discrete positions of the adjustment knob (39). Depressing the adjustment knob (39) against a second spring (59) unseats the indexer (37) for rotation of the adjustment knob between settings. In addition, a slide (71) with an inclined surface (85) bearing against the plunger (15) and coupled to the driven bevel gear (47), provides simultaneous adjustment of plunger gap (67) with adjustment of the torsion spring force to increase the range of adjustment.</p> |
