GB805125A - Improvements in or relating to stapling appliances - Google Patents

Abstract

805,125. Stapling machines. CARSTAIRS, L. S. May 23, 1956 [June 1, 1955], No. 15712/55. Class 89(3) [Also in Group XXIV] In a stapling appliance wherein staples are ejected by the release of a compression spring, a control device is provided which when operated causes an electric motor to compress the spring, the spring being automatically released when compressed through a prescribed distance. In the exemplified embodiment, a stapling machine similar to that described in Specifications 767,273 and 767,274 is actuated by an electric motor 18. The motor 18 drives a worm 25A engaging a worm wheel 25 freely mounted on a hub 34. The worm wheel 25 and hub 34 are connectable by a roller key clutch of which the roller key 36 is normally held against a spring in a declutched position by a lever 42 engaging a handle 38 projecting from the roller key. To drive a staple a button 48 is depressed causing the lever 42 to release the handle 38 allowing the key 36 to spring into a position wherein it clutches the worm wheel 25 to the hub 34 so that the hub rotates. An eccentric pin 27 carried by the hub 34 rocks a lever 30 about a pivot 31 and a spring loaded pivoted pawl 16 at the upper end of the lever 30 retracts a hammer block 14 against a spring 15 until the pawl 16 is released by striking a pin 17 to allow the block 14 to return under the action of the spring 15 to drive a staple. The mechanism continues to operate whilst the button 48 and a trigger 20 of an electric switch 19A for the motor remain depressed. In the construction described in the Provisional Specification, the pawl 16 and the manual control for the roller key clutch are differently arranged.