GB177445A - Improvements in braille writing or embossing machines - Google Patents

Abstract

177,445. National Institute for the Blind, Stainsby, H., and Howlett, A. E. June 23, 1921. Type-bar machines for braille type; type-carriages; letter-spacing mechanism; back-spacing mechanism; space-key actions.- Relates to machines of the kind in which a carriage provided with six key-operated punches slides on a bridge on the sheet-supporting board, and comprises a spacing-mechanism in which spacing- pawls on the carriage co-operate for letter-spacing or back-spacing with one or other of two racks mounted on the bridge and hav. ing teeth facing in opposite directions. The bridge 9, Fig. 1, is formed with guides 13 for the base 15 of the punch-carriage 16 and is provided with a plate 11 having bosses 12 for co-operation with the recessed ends of the punches 21, Fig. 7, to form braille characters which can be read without reversing the sheet. The bridge is provided with ball catches for engaging recesses 8 in the sheet-supporting board. 1. The punch-carriage is provided with key-levers 23 each having a recess 27, Fig. 7, receiving the round head 28 of a punch 21 which passes vertically through a guidehole in the base. The key-levers are arranged in two sets c, d pivoted on pins 24, 26, the pin of one set passing through slots 25 in the key-levers of the other set. Returning-springs 29 for the key-levers are connected to a pin 30. Spacing-pawls 36, shown in rear view in Fig. 6, are pivoted on a lever 33 having pin-and-slot connection 35 with a lever 31 which is connected by cross pins 44, 45 to a space-key lever 41, the sets c, d of key-levers engaging the pins 44, 45 respectively. The pawls are connected by a spring 39 and have pins 38 for co-operating with a letter-spacing rack 18 or a back-spacing rack 19. On depressing the punch-keys or the space-key 41, the lever 33 is depressed and one of the pawls is operative, the other pawl moving idly into engagement with the next tooth, and a pin 43 on the space-key lever engaging a rack 17 to hold the punch-carriage stationary. On release of the key-levers, the operative pawl moves idly into engagement with the next tooth. For back-spacing, the rack 18 is lowered and the rack 19 is raised into engagement with the pin 38 by means of a handlever 46, Fig. 6, having pins 47, 48 engaging the racks, the racks being formed with inclined slots 50, Fig. 6, engaging stationary pins 49. The hand-lever is provided with a catch 53 for engaging holes in a plate 51. Carriage-releasing arrangements.-The pawls 36, Fig. 6, can be raised for carriage-release by means of finger-pieces 40. Sheet-clamping arrangements.-The sheet-supporting board 1, Fig. 1, is provided with a sheet clamp consisting of stationary and pivoted bars 2, 4 provided with pins 3, 5 and holes, the bar 2 having a catch 6. Alarms; margin stops.-The bridge 9, Fig. 1, is provided at each end with a bell 54, operated by the punch-carriage 16. An adjustable stop 56 for the bridge is secured by screw 57, entering one of the holes 8.