Patent GB-190013686-A (GB)
Title: Improvements in Type Writing Machines.
Inventor: BARNES JOHN EDWARD LLOYD
Filed: 1900-07-31
Granted: 1900-11-10
Abstract: 13,686. Barnes, J. E. L., [Cahill, T.]. July 31. Type-writers. - Relates to typewriters for rapid work, in which the movement of the type-bars &c. is effected by electric or pneumatic means controlled by a keyboard having a very light touch, and so constructed that it is not necessary to release each key before depressing the next. A separate key may be provided for each character, or a keyboard consisting of a few keys may be operated on the permutational system. Fig. 6 shows a detail sectional view of a machine having a full keyboard. The key levers 5 are fulcrumed on a bar 40, and are provided with rearward extensions 43. Figs. 6 and 7, which act on latches 44 loosely pivoted to bell-crank levers 45, which are mounted on a rod 48. With each bell-crank lever is associated an arm 49 tensioned by a spring 51 and acted upon by a pin 50. When the latch 44 is lifted by the depression of a key lever, the arm 49 is thrown forward, and the movement-receiv- "ing" arm 66 is brought into position above the striking-plate 36 of the oscillating motor frame 19, The arms 66 hang from levers 60 linked to the type-bars 6. A universal bar carried by the frame 20 rests on the rear ends of all the levers 45, and a downwardly-extending arm 22 carries an insulated contact-stud 24 which, when the upward movement of the latch 44 is nearly complete, closes the circuit of the battery 236 through the electromagnet 15. The motor frame 19 is thus caused to strike upwards, and the selected character is printed. The rock-shaft which carries the motor frame 19 is linked to the " releasing-frame 30, so that the upward movement of the motor frame throws back the releasing-frame and disengages the latch 44 from the extension 43, allowing the latch to fall, and restoring all the parts to their normal position whether the key lever 5 be released or not. A variable resistance 74 in the electric circuit enables the strength of the impression to be varied as required. The paper carriage is shown in section in Fig. 20. It is supported in front by a wheel 108 resting on a roller 110, and at the back by a pair of wheels carried by a yoke-piece 84 and resting on a guide-rod 85. The yoke-piece 84 is pivoted to the rear bar 83 of the carriage, and by means of a shift-key and suitable connecting-levers the yoke piece can be swung rearwards, drawing the carriage with it into position for printing upper-case characters. A pressure roller 88 is in contact with the rear side of the platen, and paper-guiding bands 92 pass round the roller 88 and wheels 93. Spring fingers 59 hold the paper in contact with the platen, and the usual pressure roller 77 is also provided. The line-spacing mechanism consists of a ratchet-wheel on the platen and a variable-throw pawl-carrying spacing-lever. The carriage feed is effected by escapement mechanism co-operating with the rack 140, which is carried by a frame 139 projecting rearwardly from the carriage. The parts of the escapement are shown detached in Figs. 10 and 11. The fixed dog 133 is secured to a lever 130 which is oscillated by means of a link connecting it with the motor-frame rock-shaft. The spring 141 holds the dog 133 out of engagement with the carriage rack the movable dog 134 being normally in engagement therewith. The spring 138 is normally overcome by the tension of the carriage-driving spring, but serves to space the dog 134 in the usual manner when the lever 130 moves rearwardly. At the end of each word a "space-enlarging" key is pressed simultaneously with the last letter. This key effects the removal of a stop from the path of the arm 146, Fig. 11, and allows the dog 134 to move through twice the normal distance. Releasing- mechanism, including a latch 44 like that described above, is interposed between the space-enlarging key and the movable stop. A space-key actuating a non-printing type-bar in the same manner as the other keys is also provided. The inking- ribbon mechanism is driven from the carriage-driving spring drum. A pawl on the drum drives a ratchet-wheel mounted on a sleeve which also carries a mitre-wheel. By means of a hand-actuated change-over device the mitre-wheel can be caused to drive similar wheels on either of the two ribbon-spool shafts. Fig. 32 shows a sectional plan, and Fig. 31 a sectional elevation of a machine in which a comparatively small number of keys are employed. The typebars 6 are connected by rods 65 to radial levers 250. Underneath the inner ends of the radial levers 250 are spring-controlled pins 254 mounted in a rotary carrier 255, one pin being provided for every four radial levers. Each pin is normally beneath the first of the four levers, but by depressing the thumb-key 280, 281, or 282 the carrier 255 can be turned sufficiently to bring it beneath the second, third, or fourth lever of the group. Beneath the pins are arranged the segmental ends of "group-controlling" levers 264, Fig. 32. The segmental ends ensure that the lifting of any one of the levers 264 will raise the corresponding pin 254. whether it is beneath the first, second, third, or fourth radial lever of its group. To the group-controlling levers 264 are pivoted movementreceiving arms 266 corresponding to the arm 66 shown in Fig. 6, and underneath these arms is an oscillating frame 270 actuated by the electromagnet 15. Nine of the movement-receiving arms are normally clear of the frame 270, but the tenth, 267, is normally in its path. The keyboard contains nine finger keys 283, the depression of either of which causes the corresponding arm 266 to be moved into the path of the frame 270 and the arm 267 to be shifted clear of it. Forty characters can thus be written without a change of case, as each of the ten arms 266, 267 controls four type-bars. The key levers operate corresponding levers 288 by means of latches 44 as above described, and a releasing-frame 30 disconnects the latch as each character is printed. The levers 288 operate the arms 266 by means of bell cranks and links, and the arm 267 by means of a universal bar 268. When one of the finger keys is depressed simultaneously with one of the thumb keys, it is necessary that the latter be fully depressed before the electric circuit is closed ; otherwise the magnet would come into action before the carrier 255 was properly positioned, and the wrong type-bar would be struck. For this purpose the electric circuit is so arranged that, as soon as the carrier 255 commences to move from its normal position, the battery circuit is broken, and the connection is only restored when the thumb key is fully depressed. To complete the circuit and actuate the magnet, the contact controlled by the finger key must also be closed. The shift key, 320, Fig. 31, is connected by a link 326 with the shifting-lever 120, the paper carriage being constructed as described above. A space-enlarging key is also provided which, through the medium of a rod 233, removes a stop 148 from the path of the movable escapement-dog 146. In a machine constructed according to a further modification, the type-bars are linked to horizontal levers which are pivoted at the other end in groups of four to the levers from which the movement-receiving arms hang. Each time a finger key is depressed, one of these groups of four levers is therefore lifted at the end remote from the type-bar connecting-links, but no type-bar will be actuated unless a fixed fulcrum be provided for one of the horizontal levers. This is effected in the following manner :-Arranged transversely across the aforesaid horizontal levers are four universal bars or frames adapted to be held down by four electromagnets controlled by the thumb keys. Fulcrum rods rising from the horizontal levers are arranged beneath these bars, and by the holding down of one of the transverse bars one of the horizontal levers is selected from the group of four raised by the finger key and the corresponding type-bar actuated. One of the four electromagnets is normally in the circuit, but is cut out and another substituted for it when a thumb key is depressed. Instead of using an electromagnet to actuate the type-bars, a pneumatic-power device may be employed, the arm 22, Fig. 6, being linked to a valve admitting air to the bellows or like device. The valve controlling the pneumatic device may be actuated by a small electromagnet instead of by mechanical means. The releasing-frame 30, Fig. 6, may also be actuated by an independent electromagnet. Reference is made to Specifications No. 18,748, A.D. 1896, and Nos. 4977 and 10,644, A.D. 1898.