Patent GB-191402809-A (GB)
Title: Improvements in Typewriting Machines.
Inventor: BURBOA JUAN GUALBERTO HOLGUIN
IPC: B41J23/20
Filed: 1914-02-03
Granted: 1915-03-03
Abstract: 2809. Burboa, J. G. H. Feb. 3. Pneumatic type-lever actions; case-shaft mechanism ; keyboards.-In a machine for writing single characters and syllables or short words of two, three, or four letters, type-levers, operated by pneumatic mechanism controlled by keys actuated singly or in combination, are arranged in four sections A, B, C, D, the type-levers in sections B, C, D bearing single characters and being mounted on stationary supports, and the type-levers in section A bearing three characters and being mounted on a slide 229, which is moved as described below for case-shift. The type-levers may be arranged round an opening 5 for visible writing on a vertical platen 13, which is rotated for letter-spacing, suitable mechanism being provided for varying the spacing in accordance with the number of type-levers operated. The keys are arranged in two sets on inclined surfaces 3, 4 for actuation by the left and right hand respectively, each set comprising six files of three finger-keys 39, 39<1>, 39<a> and a wrist-key 55 or 55'. The keys in each row of six engage a universal bar 40, and the keys in each file of three engage a universal bar 38. The type-levers are connected by links 17 to actuating-bellows 19, one for each type-lever, the bellows associated with the type-levers in sections A, B, C, D being controlled respectively by selecting-devices 20, 20<1>, 20<a>, 20<b> connected to the keys. The selecting-device 20 consists of six rotatable disks a ... f, Fig. 8<a>, formed with ports 53 and exhaust ports 54 and arranged between a fixed plate 26 formed with ports 26<1> and a fixed vacuum chamber 22 formed with ports 25 and connected to a main vacuum chamber by a tube 24. The ports 26<1> are connected by tubes 28 to valve chambers 21<a> which communicate with the bellows 19, and tbrough tubes 51 with the main vacuum chamber. The disks a ... f are each connected by a flexible connexion or link 33 with one of the universal bars 38 under the left-hand set of keys, so that by depressing a single key or a combination of keys in the six files, one or more of the disks are rotated, and one of the ports 25 is put in communication with one of the ports 26<1> and the associated tube 28. The valve casings 21<a> are each provided with a diaphragm 45 adapted, when the associated tube 28 is connected to vacuum, to move a valve 47 and thereby connect the bellows 19 to the main vacuum chamber through the tube 51. The selecting-device 20<1> is similar to the selecting- device 20, the disks being connected by links &c. 33 to the universal bars 38 under the right-hand set of keys. The disks of the selecting-device 20<a> are connected by licks &c. 33 to levers 42 operated by the universal bars 40. The selecting-device 20<b> is used mainly for writing the frequently-occurring letters "a," "e," and consists of two disks al, bl, Fig. 2, connected by links 33', 33<a> to the wristkeys 55, 55<1>. The slide 229, Fig. 10, carrying the type-levera of section A is mounted on rollers 230 and is provided with pins 231, 232 engaging levers carried by bellows 235, 236, which are connected to the selecting-device 20<a> and are actuated for case-shift by depressing shift-keys. The slide is normally held in the position shown by a spring S. Pedal attachments.-The motors 8, 8<1>, Fig. 2, for exhausting the main vacuum chambers are operated through flexible connexions 9 by pedals.