Patent GB-191301789-A (GB)
Title: Improvements in and relating to Typewriters.
IPC: B41J23/24
Filed: 1913-01-22
Granted: 1914-01-22
Abstract: 1789. Marks, E. C. R., [Soblik-Schreibmaschinenges]. Jan. 22. Pneumatic type - wheel actions. - In actions in which separate pneumatic motors are employed for setting the type-wheel and for impression, the setting-motor is connected to the type-wheel by a flexible shaft, and is adapted to control the impression-motor. In the arrangement shown, the shaft 1 of the continuously-rotating setting-motor 2 is connected by a flexible shaft 3 to the typewheel 4 which is connected by a link 17 to a crank 16 on the shaft 29 of the impression-motor 5. The character-keys are connected to pivoted stops 9 adapted to engage a stop-arm 10 on the shaft 1, spring-pressed pivoted detents 8 being provided to retain the stops when they are raised by the keys. The arm 10 is connected to the shaft 1 by a pin and slot 10<a>, Fig. 2, and is provided with a tappet 27 adapted to be engaged by the stem 11<a> of a valve 11 carried by an arm 25 on the shaft. The valve controls a passage 26 and is adapted to open communication between an air-supply pipe 12 and a pipe 13 leading to a diaphragm or piston 6 which engages a pivoted stop 14 for the impression-motor. When any of the keys are depressed, the corresponding stop 9 is raised and arrests the arm 10, the shaft 1 making a slight further movement to take up lost-motion in the slot 10<a> and being then arrested with the selected type opposite the printing point. The lost-motion movement of the shaft is effective to carry the valve-stem 11<a> against the tappet 27, the valve being thereby opened and the impression-motor being released, and the typewheel moved to impression through the connexions described above. During the rotation of the motor 5, connexions described below are opened whereby the motor 1 is released, release being effected by means of a diaphragm or piston 7 adapted to depress the arm 8<a> of the operative detent 8 and thereby allow a spring 24 to depress the elevated stop 9 and release the arm 10. The diaphragm 7 is carried by arm 22 which is secured to the shaft 1 and is formed with a passage 23 communicating with a circumferential passage 21 in the casing 31 of the shaft 1. The passage 21 communicates through a pipe 20 with the casing 29<x> of the shaft 29, which is provided with a port adapted during the rotation of the shaft to open communication between an air-supply pipe 19 and the pipe 20, the diaphragm 7 being thereby operated and the parts restored to the normal position. The port is adapted also to open communication between the pipe 20 and an outlet 30 in the casing 29<x>. Instead of arranging the stops 9 in a circular series as shown, the stops may be arranged in an arcuate serits and be adapted to engage any one of a number of stop-arms 10, the shaft 1 being connected by multiplying-gearing to the type-wheel. Preferably there are three stop-arms, and the stops are arranged round an arc of 120 degrees, gearing being provided whereby the flexible shaft 3 is driven at three times the speed of the shaft 1. Thearrangement increases the speed of working as the shaft 1 makes on an average only one third of a revolution for each setting, instead of making a whole revolution as in the arrangement shown.