Patent GB-190215789-A (GB)
Title: Improvements in Typewriting Machines.
Inventor: THOMPSON WILLIAM PHILLIPS
Filed: 1902-07-15
Granted: 1902-09-18
Abstract: 15,789. Thompson, W. P., [Griffen, J. D.]. July 15. Type-writers.-The machine is shown in transverse section in Fig. 3, and in sectional plan beneath the platen, type-wheel, and keys in Fig. 4. From the rectangular bed-plate 10 rises a housing 11, which covers the key mechanism and guides the finger rods 101. The platen 12 is mounted on a carriage 13 provided with V shaped guides 14 which run on grooved rollers 15. The fixed guiderod 17 is embraced by ears 18 on the carriage, one of which ears is closed. The carriage is tensioned towards the left by a strap 20 wound on the spring barrel 21. The usual paper-guide, feed-rollers, scale, thumb-wheels, and line-spacing keys are provided on the carriage. The carriage feed-rack 29 engages with a double pawl escapement device 30, 31, which is pivoted to the arm 32 of a slideblock 33 adapted to reciprocate in a slideway 34. A stud on the slide-block 33 is engaged to a yoke 36, which is fastened to the spacer rods 37. The spacer rods extend to the front of the machine, and are connected by bell-crank levers 38 to the space bar 42, which thus serves to actuate the slide-block 33. Beneath the front edge of the carriage is formed a rack 44, Fig. 6, which engages with a pinion 45 on one of the two shafts 46, Figs. 4 and 6. The pinion 45 drives its shaft through ratchet gearing 49, so that no movement is transmitted during the return motion of the carriage. Bevel-wheels 55, 56 and a shaft 57 connect the shafts 46. On each shaft 46 is splined a sleeve which bears bevel pinions 49<a>, and by means of finger levers 59 the pinions can be shifted relatively to the spool pinions 51 to reverse the movement of the ribbon. The shaft 57 may be divided at the centre, and the pinion 45 be mounted near it, the two halves of the shaft being driven from the pinion by bevel gearing. The spools 53 are splined to the spindles 52, and, by pushing in the knob 68 so as to release a sliding pawl, the spool can be lifted to any required height on the toothed spindle, and fixed there, thus enabling all parts of the width of the ribbon to be used in turn. The type-wheel 69 is adapted to rotate on the spindle 73. Its own weight, together with the pressure of a spring 74, normally holds it in the lowest position on the spindle, but by means of shift-keys a vertical slide 85 can be raised, carrying the typewheel with it. An antifriction ball 87 is supported in a cup at the top of the slide 85. The spindle 73 is fixed in a slide-block 76, which moves in the slideway 34. As the block 76 advances to bring the type-wheel against the platen, it pushes the block 33 before it, and thus actuates the spacing- dogs. A spring 77 normally retracts the block 76. When the type-wheel approaches the platen, a fixed tooth 83 enters a recess in the star-wheel 79, and accurately positions the type-wheel. Springs 82, Figs. 3 and 4, pull laterally on the star-wheel 79, and tend to keep it and the type wheel 69 in the normal position shown in Fig. 4. The keys are carried by rods 101 pivoted to toggle-levers 102, 103, of which the levers 102 are pivoted at 104, and the levers 103 are pivoted to horizontal sliding key-rods 106, which are guided by antifriction rollers 109 and move rearwards when the keys are depressed. In printing, the type-wheel must first be turned into the proper position for printing the right character ; it must then be locked in that position ; and, finally, it must be advanced against the platen. These operations are performed as follows :-Pivoted at 113 Fig. 10, to the typewheel, or to the disc 80, Fig. 3, which moves with it, are two links 117, of which the forward ends are pivoted to two horizontally-sliding bars 116. Beneath each bar 116 is a locking-bar 119, somewhat longer than the bar 116 but adapted to slide in a similar manner. The locking-bars have inwardly-turned ends 121, adapted to abut against pins 120, Figs. 3 and 10, depending from the typewheel. The keyboard is divided centrally into right and left band sections. In each section is mounted a horizontally sliding frame 113, 114 in the plane of the bar 116, and a similar frame 113<a>, 114<a> in the plane of the bar 119. The frame 113 is above the sliding key-rods 106, and the frame 113<a> is below them. Each key-rod bears an upwardly-projecting pin 111 and a downwardlyprojecting pin 112, the pins being differently placed for the various characters. Fig. 10 shows one of the key-rods 106 in the right-hand half of the keyboard. In its rearward movement the pin 111 has carried the frame 113 with it and pushed back the rod 116, thus causing the links 117 to push the pivotal point 118 leftwards or backwards and turn the type-wheel through the greater part of a half-revolution. This movement is arrested when the pin 112 comes in contact with the lower frame 113<a>, and pushes the rod 119 rearwards so as to cause the end 121 to abut against one of the pins 120. Further movement of the key-rod 106 causes both the frames 113, 113<a> to move together, and the type-wheel is moved bodily rearwards without any further turning, the impression being thus effected.