Patent GB-445281-A (GB)
IPC: G06C23/06
Abstract: 445,281. Calculating-apparatus. NATIONAL CASH REGISTER CO., Dayton, Ohio, U.S.A.-(Assignees of Arnold, C. H.; 106, Sales Avenue, Dayton, Ohio, U.S.A.) Oct. 4, 1934, No. 28370. Convention date, Nov. 10, 1933. [Class 106 (i)] In a calculating-machine having a travelling paper carriage and return mechanism therefor and wherein a power drive constituted by an electric motor, a clutch mechanism, and a circuit switch arrangement is adapted to be rendered effective for the calculating operations and carriage return operations, the opening of the motor switch after a carriage return operation is initiated by declutching the carriage return mechanism from the carriage. The invention is shown applied to an Ellis machine of the type described in Specification 28253/08, [Class 106]. The start bar 36, Fig. 1, is connected to a plate 37 and a three-armed lever 39, one arm 41 of which embraces a pin 42 on the plate 37. Another arm of the lever 39 carries a pin 43 engaging a surface on a pivoted latch 45 to which is connected a pitman 47 carrying a stud 49 engaging one arm of a bell-crank 50 pivoted in the motor casing and connected by a pin 52 to a clutch release arm 53. The arm 53, Figs. 4 and 5, co-operates with abrupt surfaces of a stop cam 54 that is secured to the hub 56 of a cam 57 rotatably mounted on a stud 58, and with a rotatable plate 55 arranged between the cams 54, 57 and provided with three spring- controlled rollers 59. Depression of the start bar rocks the clutch arm 53 to free the cam 54 and plate 55. At the same time the arm 53 by its engagement with an arm 72 of a yoke 73 rocks an arm 75 which imparts an angular movement to a shaft 77 and by means of its arm 80 closes the switch contacts 82, 83 of the motor circuit. The motor armature through worm gearing drives a drum 60, the inner surface of which is engaged by the rollers 59 of the released plate 55 and transmits the movement to the cam 57. The hub 56 of the cam 57 has secured thereto a plate 67 operatively connected by a link 69, Fig. 2, to an arm on the main operating shaft 71 of the machine. A cam surface 88 on the plate operates a latch lever 86 to hold the contact arm 80 in effective position. During the cycle of movement the cam surface 88 co-operates with a roller 95 on an extension of the bell-crank 50 to effect the restoration of the arm 53 to 'clutch disengaging position and finally releases the latch 86 to open the circuit. To hold the parts in normal position, a spring-controlled arm 64 loose on the pivot pin 51 and carrying a roller 65 co-operates with a return cam 66 secured to the hub 56. If the start bar is held depressed the operation is limited to a single cycle by the provision of a pawl 97, Fig. 1, with a hook 105 that is adapted to co-operate with a hook 106 on the latch 45. The engagement of the hooks 105, 106 on the return of the pitman 47 holds the clutch arm 53 in normal position ; removal of pressure from the bar 36 rocks the lever 39 and a pin 99 by its coaction on the pawl 97 frees the latch 45. Carriage - return mechanism. The motor armature is coupled to an extension 124 geared to a vertical shaft 125, Fig. 10, to which is secured a clutch member 128 adapted to co-operate with a second clutch member 129 loose on the shaft 125 and formed with a gear engaging a rack 146 on the carriage. The carriage has a stop bar 145, Fig. 9, on which is adjustably mounted a return stop 144 with a dog 143 adapted to engage the upturned end of a slide 141 having a cam projection 140 which when the slide is displaced is depressed to rock a pair of interconnected levers 135, 133. The left hand end of the lever 133 is connected by a coiled spring 132 to a lever 131 with a forked end engaging an annular groove 130 in the clutch member 129 so that when the lever 133 is rocked the spring 132 rocks the lever 131 to raise the clutch member into effective engagement with the member 128 thus imparting a return movement to the carriage after the motor circuit has been completed. The return switch operating mechanism comprises a link 155 pivoted to the lever 135 and to an arm of a yoke member 162, Fig. 7 ; another arm of the yoke forms an escapement anchor 164, 165 which co-operates with an escape wheel to control the step movements of a cam 167. This cam by its engagement with a roller 188 on the arm 189 of the yoke 73 rocks the shaft 77 as above described to close the contacts 82, 83. The rack 146 is shiftably supported on the carriage by means of slots 147 in extension plates engaging rollers 150 on the carriage frame. To arrest the carriage in its home position the stop bar 145 carries an adjustable stop 152, an extension 153 on which engages a fixed stop bar 154 ; the rack, due to its yielding connection, moves on independently and the rollers are guided along the slots until the rack is forced downwardly at the end of this movement. The rack in this movement engages a flange on the gear member 129 and disengages the clutch members and through the levers 133, 135, and link 155 opens the motor switch contacts 82, 83. The lever 131 is retained in either of its set positions by a pawl 157. Escapement mechanism. The escapement ratchet wheel 166 and cam 167 are secured to a hub 168 surrounding a sleeve 172 carrying a gear-wheel 170 loosely mounted on a stud 171. A pin 169 on the ratchet wheel passes through a slot in the gear 170 and has attached thereto one end of a coiled spring 173, the other end of which is anchored to a pin on the gear 170. The gear 170 meshes with a gear 175 to which is secured a disc 177 carrying pins 178 extending through holes in a similar disc 180 loose on the hub of the gear 175. Between the discs 177, 180 is a pair of friction discs 183 gripping a ring gear 182 under the action of springs surrounding the pins 178. The ring gear 182 meshes with a pinion 185 loose on the stud 58. The spring 173 which drives the ratchet wheel on its release by the pawl 164 is rewound during the operation of the clutch mechanism through the friction drive 177, 180, 183. Speed-control mechanism. To control the speed of the motor its armature shaft carries a disc 107, Fig. 2, with grooves arranged to receive ball bearings 109 engaging recesses in a retaining cone 110 loosely mounted on the armature shaft. The cone 110 is bored to receive a compression spring 112 and its tapered periphery co-operates with a similarly tapered surface of a shoe 115 carried by a pivoted spring-controlled arm 116, Fig. 3, having a contact 120 that co-operates with a fixed contact on a plate 121. The plate 121 and the contact arm 116 are connected to one of the motor field contacts and to one of the contact arms 82 respectively.