GB812006A - Improvements in typewriters and the like - Google Patents

Abstract

812,006. Typewriters. INTERNATIONAL BUSINESS MACHINES CORPORATION. Dec. 20, 1955 [Dec. 29, 1954], No. 36434/55. Class 100(4) In a typewriter or like machine having a carriage capable of free forward movement and/or power-driven return movement and means for decelerating the carriage after such movement, the decelerating means comprise movable check means engageable by a co-operating stop associated with the carriage at a predetermined distance from the end of such movement thereof, and permits continued movement of the carriage at progressively decreasing speed. Margin rack 2 is movable with the carriage and when the latter returns shoulder 16 of the margin stop 4 engages shoulder 18 of margin control lever 8 sliding the latter to a limit determined by slots 9 and studs 10. This movement of lever 8 rotates bell-crank 12 counter-clockwise which rocks 68, 66 and through 64, and adjustable extension 62 rocks arm 56 counterclockwise to engage roll 60 with cam 48. Spring 72 tends to rotate cam 48 counterclockwise and in any steady state position disengages clutch 52 so that the continuously rotating shaft 46 rotates free of. cam 48. but when roll 60 tends to move cam 48 clockwise the clutch is engaged so that the cam turns with shaft 46. The cam has the form of a decelerating curve which by controlling the movement of arm 56 slows the movement of the carriage at a predetermined rate. The decelerator on the tabulator run opeiates oppositely to the carriage return decelerator. Operation of the tabulator power device rocks bell crank 24 which pivots tabulating lever 20 about axis 22 so that check lever 30 is pushed from behind shoulder 32 and freed for movement to the left, to a limit determined by slots 33, by a spring 36 acting through 42, 38, 34. Spring 90 tends to rotate cam 50 counterclockwise to a position similar to that of cam 48 in Fig. 1. As the carriage moves to the right, Fig. 1, lever 30 engages a tabulating stop and is moved to the right to the limit position shown in Fig. 1. During this movement lever 30 acts through 34, 38, 88 and 86 to rotate arm 82 counterclockwise pressing roll 80 against cam 50 so as to engage clutch 54. Cam 50 thus controls the speed of the tabulating operation of the carriage until lever 30 reaches its Fig. 1 position, when members 38, 82 assume a steady state position and spring 90 releases clutch 54. Specification 806,053 is referred to.