Patent GB-1122887-A (GB)
Title: A data entry machine
IPC: G07G1/06
Filed: 1967-05-22
Abstract: 1,122,887. Calculating machines. NATIONAL CASH REGISTER CO. 22 May, 1967 [20 June, 1966], No. 23570/67. Heading G4B. In an adding, calculating, accounting or like machine having a plurality of control keys 27-31, a blocking member 120 is provided which co-operates with the control keys and is positioned according to a previous machine operation to prevent a predetermined control key, or control keys, being operated at a following machine operation. As described, a printing calculator includes two totalizers, one totalizer driving display wheels. Digits are entered on a full keyboard 26. Control keys 27-29 cause digits set up on the keyboard to be printed but not entered in the totalizers. Control keys 30, 31 initiate add and subtract cycles. In addition, a correction key 32, sub-total key 33, total key 34, and " B " key 35 are provided. The " B " key controls printing of the contents of the second totalizer. Operation of a key 27-31, 33 or 34 energizes an electric motor 40 to drive the calculator through one machine cycle. Each control key 28-31 carries a pivotally mounted, spring-loaded member 132 cooperating with shoulders 128-131 on the blocking member 120. Control key 27 operates a bail 151 co-operating with a pawl 145. The latter is pivoted by a spring-loaded member 142 fixed to one end of a cross-shatt 140. An arm 139 on the other end of the crossshaft abuts and follows the blocking member. Engagement of the pawl 145 with bail 151 or a member 132 with a shoulder 128-131, locks the corresponding control key against movement. The blocking member is reciprocated at each machine cycle and arrested on its return movement in a position determined by the control key initiating the cycle. Associated with each control key 28-31 is a pivoted lever 155-158. An extension 159 on each lever is engaged by a stud 135 on the associated key stem. On depressing a control key 28-31, a lever is pivoted to position a lug 161 in the path of a slide 191. The latter is reciprocated on operating the machine to hold the lever 155-158 in its pivoted position by means of claw 194. A lever 165 is pivoted on depressing control key 27 to present a camming surface 165a upwardly. A latch maintains the lever 165 in its pivoted position for one machine cycle A member 200 having camming feet 206 -209 and a front stud 210 is reciprocated on operation of the machine. A stud 162 on a pivoted lever 155, 156, 157 or 158 is engaged by a corresponding camming foot on the men ber 200, whereby the pivoted lever is lifted a distance corresponding to the height of the camming foot. Engagement of the front stud 26 with camming surface 165a rocks the lever 165 still further. A selector 215 is pivoted at 190 and has an upwardly-directed arm 216 attached to a spring 27. The selector has inwardly directed studs 221-224 aligned with levers 155-158. When a lever 155-158 is lifted by member 200, an extension 161 thereof engages the associated stud 221-224 to lift the selector a corresponding amount. Likewise further movement of lever 165 lifts the selector through the action of stud 168 on the front end 215a of the selector. The blocking member has a finger 126 engaging a stepped opening 225 in the selector so that the position of the selector limits the return travel of the blocking member. The arm 216 carries a rack 216a which is engaged by a locking pawl 226a when subtotal key 33 or " B " key 35 is depressed to lock the selector 215 in position. The keys 27 and 35 are locked against movement during machine operation by a slide 103 engaging the key stems. Depression of key 35 moves a link 105 downwardly to free latch 112. The latter pivots to engage a stud 36 on the key stem and lock the key 35 in its depressed position. The pawl 145 is provided with locking shoulders 145a, 145b adapted to receive a lug 151c on bail 151. Shoulder 145b receives the lug 151c as soon as the control key 27 is restored a small distance upwardly to prevent the control key 27 being operated twice in succession.