GB798998A - Decelerating device - Google Patents

Abstract

798,998. Typewriters. UNDERWOOD CORPORATION. Nov. 17, 1955 [Dec. 8 1954], No. 32910/55. Class 100(4) [Also in Groups XIX and XXIV] The paper carriage of an accounting machine or other object movable linearly relative to a fixed member is yieldingly driven at a restricted speed and is decelerated and arrested by a stop which slides a limited amount when engaged by a projection on the object and is connected by a link to one member of an over-running clutch, the other member of which is rotated at a speed related to the maximum speed of the object. The two clutch members can rotate relatively to one another in one direction only and the speed of the second member is so chosen that the speed of the link connected to the first member cannot exceed that of the object. Tabulating movement of a paper carriage is arrested by the engagement of a column stop 35 forming a projection on the carriage with a stop arm 36 pivoted on a slide 39 on which is also pivoted one end of a link 59. The other end 61 of the link 59 is pivoted on a cap 62 fast with a cam and rotatable on a spindle 63. A casing 66 is also rotatable about the spindle 63, and within the casing and in tapered notches of the cam are spring-loaded balls tending to jam between the casing and the cam. Thus the speed of the cam, when rotated counter-clockwise by the link 59, cannot exceed that. of the casing. The latter is geared to a pinion 71 fast with one member 28 of another over-running clutch driven by a worm 32 constantly rotated by a motor, This other clutch limits the speed of the carriage during tabulating movement under the action of a spring, a rack 10 on the carriage driving the second member 31 of the clutch. As the stop arm 36 is struck by a carriage stop 35, the clutch 62, 66 acting through the link 59 prevents movement of the slide 39 at a speed greater than that of the carriage, and, as the pivot 61 of the link is moved round the spindle 63, its velocity component in the direction of carriage movement, and consequently the speed of the slide 39 and of the carriage also, is gradually reduced to zero. The carriage is released for a further tabulation by an arm 47 which, when raised, rocks a lever 46 to lower the stop arm 36 and rocks levers 54 and 52 to project an auxiliary stop 48. When lowered the arm 47 allows the auxiliary stop to be withdrawn by a spring 51 to release the carriage and allows the stop arm 36 to return to its effective position. The worm 32 also drives a pinion 12, when a dog clutch 26, 27 is engaged, so as to return the carriage. Specifications 401,904 [Group XIX] and 675,466 are referred to.