Patent GB-189800808-A (GB)
Title: Improvements in Typewriters.
Inventor: THOMPSON WILLIAM PHILLIPS
Filed: 1898-01-11
Granted: 1898-03-26
Abstract: 808. Thompson, W. P., [Turner, R.]. Jan. 11. Type-writers.-A front elevation of a type-writer with the carriage raised is shown in Fig. 2. Fig. 3 shows an end elevation of the type-writer with one of the wheels, which control the movement of the platen, removed, and Fig. 8 a cross-section view of the top of the type-writer frame and carriage frame with connected parts. The frame 13 is formed with a track bar 14 which travels upon antifriction balls 16 running in a groove in a track bar 11 mounted upon the type-writer frame 10. Antifriction rollers 18 supported by the bar 11, and a roller 19 bearing against a bar 20 on the frame 13, serve to prevent the frame from tilting sideways. The platen 24 and its connected parts are mounted in a frame 23 which is hinged to the frame 13. The mechanism for rotating the platen 24 comprises an arm 26 mounted upon the platen shaft and carrying a detent 28 which is normally forced against the ratchet teeth 25 by a spring 31; the detent 28 carries a pin 30, as shown in Fig. 3. When the linespacing lever 37 is operated, a horn on the operative end of the lever strikes against the arm 26 so as to cause the platen to rotate through one or two line spaces, and then a second horn 39 on the lever 37 strikes a pin 36, Fig. 2, so as to force a roller 34 of a detent 33 between two of the ratchet teeth and so lock the platen. The detent 33, carrying the pin 36, is mounted to slide within a sleeve 32 mounted upon the frame 23. The extent of motion of the platen is controlled by means of a segmental plate 40 pivoted to the frame 23, and provided with a handle 41, a stop 42 which engages with the pin 30 of the detent 28, and a stop 43 adapted to engage with the pin 36 on the detent 33. A tension roller 52 is mounted within brackets 50 mounted upon a fixed rod 49 and forced towards the platen by springs 51. The tension roller may be swung away from the platen by means of cams and a lever 56. A paper guide-plate 58 is fixed to the lower ends of two arms 57, and is normally held against the platen by a plate spring. Paper fingers 65, of which the central one may be stationary and the others adjustable, are secured to sleeves 63 mounted loosely upon a rod 62 which is situated above a scale bar 61. The mechanism for regulating the width of a margin comprises a stop 79, on the bar 62, adapted to stop the movement of the carriage from left to right, by striking a stop 76 projecting from a plate 74, fitted to slide within a track bar 71 ; the plate 74 can be adjusted by means of a scale bar, graduated in the same way as the bar 61, and a spring bolt 78 which enters perforations in the plate 74. The feed-mechanism comprises a frame 81 secured to the frame 10 and carrying ordinary feed-dogs mounted upon a rod 83 which is capable of slight longitudinal movement against the resistance of a spring 84. The frame 81 is fitted with a rotary rod 85 which can be adjusted by means of a thumb-wheel 90 and worm and wheel. The free ends of the feed-dogs are forced upwards by means of a rod 93, one end of which rests against an arm 94 projecting from the dogs, and the other end engages with an arm 91 mounted on the rod 85 and controlled by a spring 92. A means is provided for moving the dogs laterally, for 'shading' the letters by reprinting the same letter in a slightly different position. The correct placing of sheets of paper in the machine is effected by means of a curved arm 100, Fig. 3, pivoted to an upright 99 ; when the platen is raised, the arm 100 is forced upwards by a spring 102 and its straight edge 101 rests near the printing-line of the platen. The paper table 103 is movably supported by pivoted arms 105 so arranged that the paper table approaches the platen when the latter is raised, as shown by dotted lines in Fig. 8.