Patent GB-265135-A (GB)
IPC: G06C23/02
Abstract: 265,135. Burroughs Adding Machine Co., (Assignees of Horton, A. A.). Jan. 29, 1926, [Convention date]. Operating by motors.-In a driving mechanism for a calculating machine comprising an electric motor the motor is adapted to be disconnected from the operating mechanism of the machine at the end of a stroke of movement to permit it to return to normal by biassing means such as springs, and a switch controlling the motor is opened by a device actuated by the operating mechanism during its return movement. Means are also provided to prevent more than one operation irrespective of the time during which the starting bar is held depressed. The machine may be manually operated, and when the handle is in position the starting bar is held against depression to prevent operation of the motor. As shown applied to a machine of the type described in Specification 265,122, the motor 100, Fig. 1, through a crank 102 and pitman 103 rocks a lever 104 loosely mounted on the main shaft 71. This shaft is journaled in the side plates and carries a yoke 72 with a restoring cam 73 at one end and a driving plate 74 for the operating mechanism at the other end. The yoke 72 is loose on the, shaft 71 and is connected to a full-stroke sector 76 on a sleeve 75 loose on the shaft 71 by means of a spring or resilient connection 78. To the sector 76 is secured a long pin 77 having a roller bearing on the cam 73 and a set of stirrups 93 to which are connected restoring springs 96. The sector 76, Fig. 3. is connected to the main shaft by means of a spring-controlled pawl 83, pivoted on a stud 82 on the sector, engaging an arm 89 on the main shaft. The lever 104, Figs. 5 and 6, has its end 105 shaped like the arm 89 and co-operates with a pawl 107 similar to the pawl 83 and also pivoted on the stud 82; engagement of the pawl 107 with the end 105 is normally prevented by a latch 109 under the control of a spring connected to the said pawl and latch. A switch for the motor comprises two contact strips 112 which are adapted to be closed by a roller 113 on a lever 114 which is rocked about its pivot 115 by the engagement of a lug 118 on an arm 117 of the lever 114 with a shoulder 119 on a bar 120 connected at its forward end to an arm 121 of a yoke member operatively connected through an arm 124 to the starting bar 125, Fig. 8. Movement of the lever 114 at the same time through its engagement with a lug on the latch 109 disengages the latch to throw the pawl 107 into engagement with the end 105 of the lever 104 and thus connect the motor to the operating mechanism. At the end of the forward stroke the mechanism is disconnected from the motor by the engagement of a stud 132 on the lower end of the pawl 107 with the cam edge 133 of a bell-crank lever 134 which is raised thereby until the end of the lever meets the hub of the lever 104 whereupon the pawl 107 is cammed out of engagement with the lever 104 and the springs 96 restore the parts to normal position, the pawl 107 being latched by the latch 109. During the return movement a pin 85 on a plate 84 carried bv the stud 82 engages a shoulder 140 on a spring-controlled pawl 137 on the lever 114 so as to rock said lever back to normal position. The lever 114 is held in one or other of its operated positions by the engagement of a pin 128 on the arm 117 with one or other of the notches in a spring-controlled bell-crank lever 130. The machine cannot be operated more than once by holding down the starting bar by reason of the fact that the pin 85 during the forward stroke depresses the bar 120 to carry the shoulder 119 out of the path of the lug 118 which frees the lever 114 to permit its return to open the switch. If the machine is not in proper condition for operation, the driving mechanism is disconnected from the motor at the beginning of an operation by a safety device which throws the nose of a lever 211 into the path of shoulders 215 on the pawls 83, 107 to disengage the pawls. If during a misoperation the pin 85 is not moved sufficiently to carrv it under the. shoulder 140 of the pawl 137 the motor switch will not be opened. To ensure that this is effected an additional pawl 220a is pivoted on the lever 114 to disengage the pawl 107. The arm 124. Fig. 8, carrying the starting bar 125 is provided with a depending projection which, when the handle 70 is on the machine for manual operation. engages the hub thereof so that the starting bar cannot be depressed.