GB702715A - Improvements in or relating to file-cutting machines - Google Patents

Abstract

702,715. File-cutting machines. WALTERS, B. Aug. 14, 1952 [Jan. 4, 1952], No. 304/52. Class 83 (4) A file cutting machine of the type having a fixed head for the hammer mechanism, a cam operating a.lever to lift the hammer and to allow it to fall under spring action, and a lead screw for the work table, comprises spring-urged means to hold the hammer out of operative connection with the cam and means operable by the operative to overcome the spring urge to enable the cam to operate the hammer. The lead screw 1 of the machine traverses a table 3 from left to right to enable a tool secured in the .slot 4 of the hammer slide 5 to cut a blank held on the spelter bed 6 supported by the table. The blank is held by a foot 7 carried by a weighted lever 8 the weights 9 of which may be raised by a pedal 10 to disengage the foot from the blank. A lever 11 controls a half nut by which the table is engaged to and disengaged from the lead screw 1. The hammer slide 5 works in an inclined fixed head 12 and is downwardly urged by an adjustable spring 13. A cam 14 raises the slide 5 against the spring by engaging the rear end 15 of a pivoted lever 16 the forward end 18 of which engages a shoulder on the slide. A projection 19 on' the lever 16 is engaged by a projection 20 on a downwardly spring-loaded plunger 21 and the lever is held clear of the cam 14. The plunger 21 is connected by means of a pivoted lever 27 and a link 31 to a pedal lever 32 depression of which raises the plunger 21 and allows the lever 16 to engage the cam and so operate'the hammer. The plunger 21 may directly engage the slide 5 when raised by the spring thus holding the slide clear of the lever 16 until the pedal 33 is depressed. When a row of teeth have been cut the operator withdraws the half-nut from the lead screw 1, releases the pedal 33 so that the hammer is held inoperative by the spring 22 and the table 3 is returned by a weight 34 attached to the table by 'chain 35 which passes: over a roller 36. The rate of return up to a stop 37 is controlled by the lever 11. Alternatively, the table may be returned by means of a hydraulic cylinder the piston of which is connected to the table by a chain a two-way valve being coupled to the lever 11 to control the rate of return.