Electrical circuit breakers
AssigneeDorman Smith Switchgear Limited
InventorsAlan Lister Kidd, Douglas Eaves, Keith Walmsley
Life of this patent
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Abstract
An electrical circuit breaker having a thermal element which on being heated by fault current trips the breaker, and including an adjustable member to vary the action of the thermal element thereby to vary the rating of the breaker, said adjustable member comprising a slide displaceable by an eccentric boss rotatable by means of an external knob.
Claims6
In an electric overload protection apparatus including a thermal element which on being heated by fault current is deflected towards a pivotable trip bar for tripping a circuit breaker, the improvement in a means for varying the action of the thermal element and thereby varying the rating of the circuit breaker comprising:
- a slide displaceable relative to the thermal element,
- a camming element pivotable in response to movement of the slide,
- a manually operable externally accessible knob having a recess,
- a rotatable boss eccentrically and adjustably mounted in the recess of the knob, with rotation of the knob achieving corresponding linear displacement of the slide in a plane substantially parallel to the thermal element.
Dependencies are inferred from the claim text.