Patent GB-700112-A (GB)
Title: Improvements in or relating to embossing machines for producing printing plates
Inventor: GRUVER JOHN HENRY
IPC: B41J3/38
Filed: 1951-02-14
Abstract: 700,112. Typewriters ; embossing. ADDRESSOGRAPH-MULTIGRAPH CORPORATION. Feb. 14, 1951, No. 3570/51. Classes 100 (2) and 100 (4) Machines for embossing plastic material; Type lever machines; Hammer impression arrangements; (Figs. 1, 2, 4, 5, 7, 8, 10, 13, 13A and 13B).-An embossing machine 20 for forming embossed type characters one by one on a plastic printing plate P includes a plurality of type heads 25 having die cavities formed therein and operated in known manner on levers 22 so that when a key K is depressed each type head is moved to the same working position, a carriage C for supporting and positioning a plastic printing plate for co-operation with a type head, an anvil 112 movable into position to hold a type head in working position, and a pressure applying ram 160 for forcing the printing plate P into cooperation with a type head in the working position. The machine comprises a typewriter frame F and an operating unit 100 which supports an operating head structure H. The unit 100 comprises frame plates 101, 102, 103, supporting a motor 135, and a frame plate 105 supporting at its forward end a bracket 108 which has a slot 109 formed therein through which the printing plate P and its supporting member 49 may pass in any line spacing position of a cross slide 45 which is slidably mounted on guide rods 46. A slot 110 is also formed in the bracket 108 to accommodate a type head 25 in working position. Upon depression of a key K a type head 25 is raised to engage a tooth 120T on a disc 120 so as to revolve the disc against the action of a spring 124. As the disc 120 is revolved an upstanding portion 120S thereon, normally holding the anvil 112 in its inoperative position, releases the anvil and after the type head has entered the slot 110 the anvil moves under the action of a spring 115 to secure the type head in position. As the anvil moves into operative position it operates a resilient arm 153 to operate a switch 151 thereby energizing a solenoid 145 which serves to operate a one revolution clutch to cause a shaft 130, mounted to bearings in the unit 100, to execute one revolution. On the shaft 130 is mounted a cam 170 engaging the upper end of a lever 164 which has a head 164H at its lower end co-operating with the pressure ram 160. Cam 170 causes the lever 164 to rotate in a clockwise direction thereby forcing the ram 160 against the back of the plate P and impressing the plate P on the type head 25. The plate P is thus formed with characters 26 and recesses 160P. As the cam 170 is rotated the ram 160 is retracted. Also mounted on the shaft 130 is a cam 129 and as the shaft is rotated the cam 129 engages the anvil 112 to move it back to its inoperative position thereby de-energizing the solenoid 145 and allowing the type head to return to its retracted position. As the type head has moved from the slot 110 the disc 120 rotates under the action of the spring 124 and the portion 120S retains the anvil 112 to inoperative position. The one revolution clutch mechanism comprises a sleeve 133A rotatably mounted on the shaft 130 and continuously driven by the motor 135. A second sleeve 133B, spring biased into engagement with sleeve 133A, both sleeves having teeth 133T thereon, co-operates with a sleeve 133S fixed to the shaft 130. Sleeve 133B has a pin 135' thereon with a cam surface 136C on a lever 137' pivoted at 138' on a bracket mounted on the frame plate 105. As the pin 135<SP>1</SP> rides along cam surface 13'6C the sleeve 133B is moved out of engagement with the sleeve 133A. The cam 136C is provided with a stop against which the pin 135<SP>1</SP> bears. When the solenoid 145 is energized. however, an armature 145A carrying a lever 146 is pulled downwardly to rotate the lever 137' in an anti-clockwise direction thereby disengaging the pin 135' from the cam 136C so that sleeve 133B moves into engagement with the sleeve 133A and the shaft 130 begins to rotate. As the lever 146 is moved downwardlv by the solenoid it is rotated in an anti-clockwise direction so that it releases the lever 137<SP>1</SP> which returns to its initial position to prevent more than one rotation of the shaft 130. Upon de-energization of the solencid 145 the lever 146 returns to its original position under the action of a snring 147 a tooth 146T being provided on the lever 146 to allow it to regain control of the lever 137'. Letter-spacing and line-spacing arrangements: (Figs. 2, 12, 13, 14).-The letter-spacing mechanism comprises a carriage 32 movable in known manner on depression of the keys from right to left which is provided with a rack 38 which cooperates with a pinion 40 mounted on a fixed bracket 35. The pinion 40 also co-operates with a rack 39 on the carriage C so that this carriage moves from left to right. Mounted on the carriage C are guide rods 46 on which the cross slide 45 is slidably mounted. The cross slide 45 comprises sleeves 47 provided with racks 52 and a cross piece which supports the plate supporting members 49. The slide 45 is biased downwardly by springs 50. A shaft 56 carrying a ratchet 62 has mounted on its ends gears 54 which cooperate with the racks 52 so that on rotation of the ratchet 62 the cross slide 45 may be moved upwardly to effect a line space. The ratchet 62 is provided with two pawls 64, 72 the pawl 72 being pivoted on a rocker 70 having a roller 78 mounted thereon for co-operation with a cam 81 mounted on the carriage 32. After the end of a line the carriages are returned to their initial positions and during this movement the roller 78 rides under the cam surface of the cam 81 causing the pawl 72 to rotate ratchet 62 to effect a line space. The cam 81 is pivoted for anti-clockwise rotation so that on the return movement of the carriage it rides over the roller 78. After the complete plate has been embossed the carriages are moved to the position shown in Fig. 14, ie. the furthest extent of movement of the carriages in the opposite direction to that required for a line-spacing movement, whereupon the pawls 64, 72 ride under a cam surface 85 so as to release the ratchet 62 and allow the cross slide to return to its lowermost position. After a new plate has been inserted the carriages are moved to their other extreme positions so that the new plate may be embossed.