Patent GB-1172819-A (GB)
Title: Keyboard Mechanisms.
IPC: B41J5/22
Filed: 1966-12-23
Abstract: 1,172,819. Selective printing. FRIDEN Inc. 23 Dec., 1966 [25 Jan., 1966], No. 57815/66. Heading B6F. Keyboards; key construction; permutation type selecting mechanisms; preventing repeated power action; keys operating electric contacts.-A selective printer associated with a data processing machine is provided with a keyboard having a number of banks of keys 30, Fig. 1, each of the keys being associated with a permutation slide 47 for generation of a code associated with the character of the key, whereby the permutation slides are fitted with a latch 62 which prevents depression of the other keys until a depressed permutation slide 47 is restored to its raised position by a bail rod 74 on a bail 73. Depression of a key 30 results in pivoting of an associated key lever 18, which is rocked on a rod 21 and guided at its opposite free end in a guide comb 32, such that a key pawl 39, which is mounted by a pair of studs 41 and a slot 40, engages a shoulder of the slide 47, Fig. 13, to rock the slide downwardly and cause the latter to move rearwardly under the action of a spring 57, Fig. 1, whereby the coded projections which depend from the slide tilt the respective vanes 70 to generate signals, representative of the depressed key, by closing appropriate ones of the switches 01 ... C9 (Fig. 31). The slides are also provided with a projecting plunger 67 which in addition actuates switches SC. The permutation slides are restored by the bail 73 which engages a lug 90 to restore the slides 47 against the bias of spring 57 by forcing a nose 58 into upward rolling contact with a roller abutment 59. Since the key pawl 39 does not re-engage the shoulder of its slide 47 until the depressed key is released repeated power action is prevented. The pawl 39 may be replaced by a slidable pawl 39<SP>1</SP>, Fig. 29, provided with a lug 161, which, on depression of a key 30, co-operates with a lug 162 on the permutation slide 47, thereby the sliding movement induced by the spring 57 causes the lugs to disengage as the nose 58 rides under the roller abutment 59. Permutation slides are interchangeable by loosening fasteners 168 (Fig. 30) on the lower slide supporting bracket 72 and removing or replacing the selected slides. Key interlocks.-An inadvertent depression of any other key following the depression of a key is prevented by latches 62, Fig. 1, on the permutation slides 47. The latches 62 displace balls 63 which are disposed in a groove provided in a support 14, the depressed slide 47 being maintained in its actuated position, during a subsequent sliding movement, by the nose 58 which engages the lower extremity of the roller 59. The keyboard is locked during re-setting of the permutation slides 47 by a bail rod 74 which continues to move counterclockwise under the lug 90 and stays in that position until a printing cycle is completed. During the printing of upper case characters selected keys are interlocked by one or more bails 101, 101<SP>1</SP>, which are provided with upstanding tabs engaging lugs 111, Fig. 17, or a depending portion on a key lever 18. The bails are rocked by electromagnets 108 (Fig. 3) which are energized by case-shift or special keys. An upper case-shift key 18d, Fig. 24, is provided with a lug 135 depressing a micro-switch which actuates a leaf spring 132 biased upwardly by a further leaf spring 136, whereby in the depressed position (shown in phantom lines) both springs are held down by a dog 137 which is mounted on a spring biased, pivotal latch 138 having a cam surface which is engaged by a pin 144 on a lower case-shift key 18e (Fig. 26), when the latter is depressed, so as to rock the latch away from the leaf springs 132, 136 and release the upper case-shift key 18d. In a modification the upper case-shift key 18<SP>1</SP>d, Fig. 27, is provided with a pawl 138<SP>1</SP> which engages with its lug 153 an aperture 154, provided in a frame mounted bracket 155, when the upper case-shift key is depressed, the pawl 138<SP>1</SP>, which is biased counterclockwise by the leaf springs 132<SP>1</SP>, 136, being restored by its spring 141<SP>1</SP> on depression of the lower case-shift key 18<SP>1</SP>e. The latter is provided with a pawl 157 having a notch 158 which relieves the bias of the leaf springs. Key touch regulating arrangements.-The keys 30, Fig. 17, are restored from their depressed position by leaf springs 24 on a bail 25 which is mounted on a crank arm 96 provided with a pin 97. The pin 97 co-operates with a manually displaceable cam disc 99 having a cam contour 98. Case-shift key actions.-The upper case-shift key 18d, Fig. 24, is provided with a lug 135 which depresses a leaf spring 132 to actuate a micro-switch when the key 18d is operated. Perforating machines.-The displacement of permutation slides 47, Fig. 1, and the associated actuation of the electric switches C1 . . . C9 (Fig. 31) and SC is utilized for the operation of a perforating machine which is attached to the selective printer.