Cable-controlled electrical safety switch device
AssigneeLa Telemecanique Electrique
InventorJean-Luc Piccoli
Life of this patent
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Abstract
A cable-controlled electrical safety switch device comprises a piston 15 tensioning a cable 2 under the action of a spring 23 via a rod 10 and a screw thread 12a for adjusting the tension of the spring and of the cable. A piston groove 25 actuates a push member 28 for the switch 40. The piston is angularly adjustable. The flank 32 of the groove remote from the spring is helicoidal. When the cable is long, a higher tension is selected so that the groove flank 31 moves away from the push member 28. This distancing is desirable in order that any length variations due to heat--which are greater with a long cable--may be prevented from triggering the switch. The clearance between the other flank 32 and the push member 28 is then corrected by rotation of the piston.
Claims10
A cable-controlled electrical safety switch device, comprising
- a casing;
- a movably assembly disposed within said casing and having a portion adapted to be connected to a cable, said movable assembly being mounted for movement within said casing in a first direction and a second direction opposite said first direction, said movable assembly comprising a spring supported within said casing and resisting movement of said movable assembly in said first direction, said movable assembly further comprising a rotatable cam element having a periphery defining a groove formed between two cam flanks, said groove having a varying width extending parallel to said first direction of movement;
- a switch actuating member mounted in said casing for movement along a third direction of movement transverse to said first and second directions, said switch-actuating member having a portion projecting into said groove, and
- means for selectively rotating said cam element about said first direction of movement so as to adjust a distance, as measured parallel to the first direction of movement, between the projecting portion of the actuating member and at least one of the cam-flanks, wherein said actuating member is actuated by a first said cam-flank when the movable assembly is displaced by the spring along the second direction of movement and said actuating member is actuated by a second said cam-flank when the movable assembly is displaced along the first direction of movement against the force of the spring.
Dependencies are inferred from the claim text.