Patent GB-668287-A (GB)
Title: Improvements in stamping or embossing machines
IPC: A43D95/14
Filed: 1948-11-18
Abstract: 668,287. Embossing and stamping. POCHIN, H. W., DOVE, G. H., and SWAIN, R. P. Nov. 18, 1949 [Nov. 18, 1948; May 3, 1949], Nos. 29997/48 and 11760/49. Class 100 (ii). [Also in Group XXIV] In a stamping or embossing machine, the stamp is actuated by pressure fluid under control of a first valve, means being provided under the control of a second valve for operating the first valve to determine automatically the period for which the stamp is in contact with the work. The stamp on the end of a plunger P is actuated by a double acting pneumatic cylinder G, which is hinged to one end of a cross-beam Q pivoting about a pin R, and which is connected to an airdistributing valve D operated through toggle mechanism by a trip arm F. To actuate valve D to move the plunger P towards the work, a vertical treadle rod X, in fixed slide bracket, is depressed so that a latch E on the rod X engages a peg Y carried by a lever T, hinged about a horizontal axis'to outer casing N, to move the lever T downwards and a plate U thereon engages a roller V on a projecting stud W on the trip arm F. Continued movement of rod X causes arm F to move down until latch E is disengaged from peg Y by a pre-set trip screw D 1 , the lever T being returned to initial position by a compression spring E, mounted about a vertical rod and connected to lever T by a cross head and pair of links. To actuate valve D to reverse the operation of cylinder G after embossing has been effected, a double acting pneumatic timing control cylinder H is provided, which is connected to valve D and under the control of an adjustable air flow regulating valve J incorporated in the air line to cylinder H, the piston rod of the cylinder H carrying a pusher knob K positioned under arm F, so that as knob K rises, it will eventually bear against and lift arm F to reverse the valve D causing the plunger P to rise and knob K to fall. Feed of coloured embossing paper is effected by a double acting pneumatic cylinder L also connected to valve D in parallel with cylinder G and having an adjustable airflow regulating valve M in the return air line to avoid jerking of the paper which is fed on the return stroke of cylinder L from a rod L 2  to a reel L 3  by way of a link and ratchet arrangement L 4  having a stroke adjustable by a block L, engaged about a threaded rod L 6 . Pressure air is admitted to valve D by a remote control valve A having an operating- arm with on, off, positions. Cylinders G, Hand L may be single acting with appropriate alterations to valve D. Safety devices.-A branch in the air line from A to D leads to a single acting cylinder B whose piston rod, is linked by a lever A, to a safety guard C supported by a horizontal slide Z so that the guard C is brought into position before the machine can be operated and maintained until valve A is closed. A safety bell crank lever B 1  co-operates with guard C to prevent operation of rod X if guard C is not in position; the lever B 1  being pivoted on a vertical shaft and carrying at one end a plate L 1  to be engaged by a roller K, on slide Z so that as guard C comes into operative position, a block H 1  on the other end of the lever B, moves out of the way of a catch plate J 1  on rod X, a tension spring normally holding block H 1  in the path of plate J 1 . A reducing valve may be incorporated in the air line to cylinder G as a safety measure, a bye-pass trip valve being actuated by the stamp block when it nears the work so that full pressure is applied only when the stamp is within a short distance of the work.