GB1071524A - Two-position mechanism - Google Patents

Abstract

1,071,524. Releasable-fastenings. A. F. BULGIN & CO. Ltd. Nov. 10, 1965 [Aug. 21, 1964]. No. 34313/64. Heading E2A. [Also in Division H2] A two position mechanism comprises a member 9 mounted to slide in a framework between the two positions, means 19 serving to bias the member into the first position, a plunger 4 having a part 18 which can engage a part 17 carried by the sliding member and a latch 26 which can engage with the sliding member, the arrangement being such that when the plunger is depressed initially the part 18 of the plunger engages the part 17 and moves the sliding member 9 from the first position to the second position in which the latch engages with the sliding member, so as to hold the member 9 in the second position upon release of the plunger which returns to the initial position, depression of the plunger a second time causing the plunger to act upon and release the latch from engagement with the sliding member which is then returned to the first position under the influence of the biassing means. In the construction shown the part 17 is a pawl and the part 18 is a notch in the plunger; the plunger is biassed to its initial position by a spring 6 and the latch is biassed by a spring 27 to the position in which it engages a wall of an aperture 25 in the sliding member 9 when the plunger is depressed; when the plunger is depressed for the second time it does not engage the pawl 17 since once the pawl is released by the notch 18 it is pivoted out of the way of the part 18 by the biassing means 19, thus the second depression of the plunger 4 allows it to be depressed enough to engage the latch 26 and pivot it from engagement with the aperture 25 wall; the means 19 then moves the plunger 9 back to its initial position and the spring 6 restores the plunger to its initial position; during the movement of the member 9 to its initial position the pawl 17 engages a bevelled part 23 of the framework which moves it to the position in which subsequent depression of the plunger causes the notch 18 to engage the pawl. The sliding member may have electrical contacts secured to it in such a position that they contact electrical terminals fixed to the framework; alternatively the sliding member can mechanically move an indicator flag.