Patent GB-1004128-A (GB)
Title: Improvements in or relating to keyboard operated machines
IPC: B41J5/22
Filed: 1964-03-02
Abstract: 1,004,128. Typewriters. INTERNATIONAL BUSINESS MACHINES CORPORATION. March 2, 1964 [March 18, 1963], No. 8654/64. Addition to 930,475. Heading B6F. Machines with types upon spherical surfaces; type selection and actions using auxiliary power; type carriages.-A typewriter of the type having a single type head 2, Fig. 2, which can be rotated and tilted by bands 52, 55 respectively, for type selection and which is traversed along a platen 61 on a carriage 70, has a plurality of code strips 16 and check strips 17, Fig. 1, co-operating with interposers 6 associated with respective key levers 1 to effect a type selection. In operation, depression of a key lever 1 flexes an element 4, whose finger 5 releases a projection 10 latching the interposer 6 with a cross-bar 11, whereupon the interposer is urged into its operative position by a spring 8 and a finger 14 on the interposer 6 moves into openings 20, 21 of the code strips 16 and check strip 17, there being six strips of each kind extending in a mutually overlying relationship. At the same time a projection 45 on the interposer 6 pivots a bail 44 which through a link 48 releases a half-revolution clutch 36 so as to couple a shaft 32 to a continuously rotating shaft 34. Rotation of the shaft 32 displaces a cam 31, whose follower 30 pivots an arm 28 to allow lateral movement of only those code and check strips 16, 17 (under the influence of springs 25 passing through openings 24), which have a large opening 20, the remaining code and check strips having a small opening 21 being arrested by the finger 14 of the interceptor 6. The displaced code strips 16 operate bell cranks 63 whose levers withdraw corresponding driving latches 60 from under a bail 58. Continuous rotation of the shaft 32 displaces a cam 96 whose follower 93 releases a clutch tape 91 whereby the spring urged clutch tape 91 rocks a bell crank 85 the articulated pull rod 84 thereon releasing a clutch 76 to rotate a shaft 68, having mounted thereon cams (not shown) which operate the bail 58, the operated combination of driving latches 60 rocking arms 54 and 57 to rotate and tilt the type head 2 for character selection. Continued rotation of the shaft 68 pivots the type head for impression via cams 69. Following impression the cam 96 pivots the bell crank 93 once more to displace the clutch tape 91 against the spring 92 to arrest the clutch 73 and the cam 31 restores the displaced code and check strips to their original position by means of an arm 28, whilst a cam 110 on the shaft 32 rocks a follower 111 to operate the bail 44, which on the one hand returns the interceptor 6 so that the projection 10 thereon may latch the interceptor with the cross bar 11 and on the other hand arrests the clutch 36 via the link 48. Key interlocks.-To prevent a type selection action when more than one keys are depressed inadvertently check strips 17 are provided with their openings 20, 21 arranged in a complementary manner i.e. a large opening 20 in a code strip 16a (Fig. 3, not shown) is complemented by a small opening in a check strip 17a, so that when one or more fingers 14 of the corresponding interposers 6 enter the originally aligned openings 20, 21 the code strips 16 and check strips 17 are only displaced partially when released by the arm 28, whereby slots 101 in the code strips and check strips are so aligned that they expose one or more of apertures 103 in the clutch tape 91. These apertures act as detents for fingers 100a . . . 100f, Fig. 1, one or more of which engage the detent apertures 103 when a bail member 98 carrying these fingers is rocked by a cam 108 following release of the code and check strips to prevent lateral displacement of the clutch tape 91 to prevent releasing of the cam 73 and execution of a type selection. Key construction.-Each of the key levers 1 is attached at its rear end to a support member 3 by means of a leaf spring permitting pivoted movement in a vertical plane. Each key lever is associated with a flexible element 4 having a finger 5 acting against the interposer 6. Perforating, punching and other machines associated with typing operation; keys operating electric contacts.-The control strips 16 may be arranged to control also the selection of punch elements which may be driven by the shaft 68. They could also operate electrical contacts in circuits which may be completed on the rotation of shaft 68 for producing pulses representative of characters corresponding to the key levers actuated. Specification 875,920 is referred to.