Patent GB-555659-A (GB)
Title: Improvements in or relating to calculating or like machines
IPC: G06C11/04
Filed: 1942-05-08
Abstract: 555,659. Calculating-apparatus. BURROUGHS ADDING MACHINE CO. May 8, 1942, No. 6238. Convention date, June 26, 1941. [Class 106 (i)] [Also in Group XVI] A printing calculating machine is provided with means to print characters or symbols to the left of the highest significant digit in order to prevent subsequent alteration of the printed amount. The means described comprises a character type element mounted for movement in a direction parallel to that of the numeral type members and movable thereafter transversely of the type members to an extent determined by the displaced type member associated with the highest significant figure, and actuating means for effecting an impression. The invention is shown applied to a Moon-Hopkins typewriter calculating machine, Fig. 1, with the usual type keys 20, numeral keys 25, actuator racks 30 with type members 31, and totalizers 35. The main shaft 40 is driven by an electric motor through a clutch 42 and linkage 46, 47 and 48. The platen P is provided with a shift mechanism operated by a shift key 60. Depression of the key rocks a shaft 64 which is operatively connected to a lever 66, Fig. 3, with a roller 68 bearing against the cross member 52 of the platen frame so as to displace the platen from the A to B position, Fig. 4. The platen occupies the A position during the forward stroke of the operating shaft 40 when printing amounts and is moved automatically to the B position for receiving the character impression from the type member 108 on the return stroke of the shaft. For this purpose the main shaft 40 carries an arm 70, Figs. I and 2, with a pin 71 which, on the forward stroke, passes a byepass pawl 72 pivoted on a spring controlled link 74 but on the return stroke engages a shoulder on the pawl to move the link 74 rearwardly. The link at its forward end is connected to a lever 82 which engages at its upper end a bell crank lever 85, Fig. 3, pivoted on a slide 87 arranged on a supporting member 92. The slide is urged forwardly by a spring 90a but is normally held in i:s rear position by the spring 81, Fig. 1, of the slide 74. The front end of the slide is formed with transverse portions 87a, 87c and the forward arm of the bell crank 85 carries a roller 95 bearing on a stud 96 on a spring controlled arm 97 pivoted on the front portion 87a. A slot in the arm 97 receives a stud 100 carried by an arm of a bell crank 101 the other arm of which is slotted to receive a stud 103 secured to a slide 104 guided by slots in the front portion 87a. The slide 104 is formed with a guide 106 to receive the stem of the character type element 108 and a stud 109 on the stem projects into a slot in an arm of a spring controlled bell crank 110. During the initial movement of the link 74 on the return stroke the slide 87 is caused to move forwardly carrying the type element to the position 108a in front of the normal position of the type carriers 31. At the same time a spring 88 holds the bell crank 85 against counterclockwise movement, Fig. 3. Continued movement of the link 74 rocks the bell crank 85 thus allowing the arm 97 to follow to rock the bell crank 101 and thereby to shift the slide 104 and character type element 108 to the left, Fig. 3, to the position 108b where the guide 106 bears against the highest order type bar displaced from its zero position. The extent of movement is limited by the length of the slot 103a in which the stud 103 works. The movement of the lever 82 is utilised to shift the platen P by a projection 115 thereon rocking a lever 116 which through a lever 118 and yielding linkage 120, 122 rocks the platen shift lever 63. The impression of the character type is effected by a printing hammer 125 operated by a projection 126 on the lever 118 that co-operates with a pivoted pawl 127 to rock a leverage 130, 133 which pulls on a link 135 attached to the hammer. On the return movement of the link 74 the parts are restored to normal position. A pawl 138, Fig. 2, associated with the pawl 72 prevents too rapid return of the link 74. Automatic control of character printing.-The operation of the character printing may be controlled automatically to occur only in certain columnar positions of the platen carriage. For this purpose the byepass pawl 72 is held normally in inactive position by a stud 75 thereon engaging the end of a slot in a link 140 which is connected at its upper end to a spring controlled lever 141. The forward end of the lever 141 has a stud and slot connection with one arm of a lever 144 the other arm of which carries a roller 145 to co-operate, in selected columnar positions of the carriage, with a cam plate 146 on the carriage frame so as to rock the lever 141 and to permit the pawl 72 to assume its active position. Specifications 18058/07, 18320/08, 18321/08 and 18322/08, [all in Class 1061, are referred to. U.S.A. Specifications 1,027,225, 1,120,862, 1,259,929, 1,336,904 and 1,774,287 also are referred to.