Patent GB-661090-A (GB)
Title: Improvements in printing or typewriting machines of the keyboard type
IPC: B41J1/32
Filed: 1948-02-04
Abstract: 661,090. Typewriters &c. ABBEY, A. (Chisholm, C.). Feb. 4, 1948, No. 3259/48. Class 100 (iv). A typewriter comprises a movable type carrier 14 controlled by keys to bring a selected type into printing position, and a platen carriage 11 mounted for letterspacing movement and for key-controlled power-operated impressional movement in a horizontal plane passing through the type arranged on the carrier 14, the impression being effected by a pair of pivotally - intercon - nected links 197, 199, Fig. 4, pivoted about spaced axes 57, 58 positioned in the horizontal plane and which are arranged to be swung from a position at an angle to each other to a position substantially in alignment with each other. The machine comprises a main frame 10, Fig. 1, and the platen carriage 11 is made up of end plates 30, 31 spaced apart by cross members 32, 34 and supporting work-positioning guides 50. The carriage travels longitudinally on the pair of rods 57, 58, Fig. 4, and is capable of transverse impressional movement relatively to rod 57. The rod 57 is rotatable in the frame 10 and the rod 58 is movable relatively to the frame and fixed relatively to the carriage, so that upon partial rotation of the rod 57 a series of interconnecting links 197, 199 move the rod 58 in guideways 60 formed in side brackets 55 mounted on the frame 10 thus moving the carriage 11, and consequently a plastic platen 12 mounted in the cross member 34, to effect impression by moving a paper sheet, fed between rollers 35, 36 against an ink ribbon and the type. The thrust of the impression is taken by a fixed bar 56 on the carriage through a collar on rod 57 and screw 208 in bar 56 thus avoiding springing of the rods 57, 58 under the impact of the impression. The rotation of rod 57 is effected at every depression of a character key 28, Fig. 5, which moves a lever 135 against the tension of springs 138 and disconnects a pin 140 from a notch 141 in a lever 142 which is thereby able to be moved clockwise by springs 144 so that a universal bail 150 is engaged. The movement of bail 150 trips a latch of a one-revolution clutch to effect rotation of a shaft 153 from a continuously-rotated drive. Shaft 153, extends across the width of the machine and on its rightward extremity carries a cam 190, Fig. 2, engaging a follower 192 on a link 193 adjustably connected to a lever 194, secured on the platenactuating rod 57. The adjustment comprises an eccentric pivot 189, carrying a notched disc 211 into which a plunger 213 is resiliently held. A shaft 83 driven through a slipping clutch has a spiral-gear connection to a vertical shaft 70 which rotates the carrier 14. The typecarriers are positioned by the individual character and spacing keys 28, 23, each key when operated causing the hooked end 146 of its lever 142, Fig. 5, to engage a notch 147, formed in a disc 148 corresponding to the type chosen keyed on the shaft 83 thereby stopping the shaft to position the required character on the carrier 14 in the impression position. The carriers are locked in the selected position by a plunger 180, Fig. 3, which engages a notch 181 in a disc fast on the shaft 70. Plunger 180 is operated by a linkage 178-172, actuated by a follower 171 running on a cam 170 on the one-revolution shaft 153. Each of the type carriers 14 has a different size type from the others, and is circumferentially fixed but axially slidable on the shaft 70 so that the carrier to be used can be moved into impression position, and the particular carrier 14 in use can be moved from lower case 72 to upper case 73 by a solenoid 100, Fig. 2, which is energized by a shift key 90.