Patent GB-190328040-A (GB)
Title: Improvements in Typewriting Machines.
Inventor: DISS LOUIS PHILIP
Filed: 1903-12-21
Granted: 1904-04-28
Abstract: 28,040. Diss, L. P. Dec. 21. Type-writers.-Relates to means for supporting and shifting the platen, and for controlling the shift of the platen. The carriage has a bar 22 grooved on its underside, and supported over a similar bar 23 by rollers 24. Accidental displacement of the bars is prevented by a plate 25 fastened to the bar 23 and bent so as to enter a groove in the bar 22. The platen frame is supported by forwardly-extending arms 28 on the carriage, which also has arms 29 extending rearwardly and supporting a rail 30, the straight top of which is engaged by a roller 31 carried by a bracket 35 on the top-plate 3 of the machine. A bent wire 36, attached to the bracket and extending under the rail, prevents accidental displacement. The shaft 57 of the platen is journalled in the end-pieces 58 of the platen frame, each end-piece having three arms 59, 60, 61, and the corresponding arms are rigidly connected by bars 62, 63, 64, forming a rigid frame which is pivoted to the arms 28. The platen is raised or lowered by a key lever 66 pivoted on a pin 67 fixed to a bracket 68 on the base frame of the machine, the lever being guided by pins 10. The key lever is adapted to operate a rock-shaft, the ends of which are reduced and journalled in recesses in fixed rods 82, carried by brackets depending from the top-plate 3. An arm is secured to the shaft, and a roller is mounted in a block 94 which is, in turn, pivotally mounted in notches in the forked end of the arm. The roller bears against a flat face on the bar 64, and so supports the platen frame. The oscillation of the block 94 on its pivots is limited by a screw 97 engaging in a slot 96 in the block. The normal position of the platen may be adjusted by a set-screw 100 in the top-plate, which limits the backward motion of the forked arm 88. The forward motion of the arm is limited by a set-screw 103 which engages a projection 104 on the top-plate. For locking the key lever 66 in its depressed position, the key head 106 which is pivoted to the lever, has a nose 111 which may be pushed under a pin on the base frame by tilting the head. The head is held in its normal position by a spring 110. The bar 64 is prevented from leaving the roller 94, should the shift lever 66 be too forcibly depressed, by a curved finger 119 on a plate 113 pivoted to the forked arm. The motion of the plate is limited by a pin and slot 115, and the plate is pressed upwards by a spring 117. To allow the platen to be raised by hand for the purpose of making erasures, a special key lever is provided at the opposite side of the machine from the shift lever. This special lever does not engage the universal bar, and is connected by a link 123, to a crank arm 125 forming part of a rock frame which is pivoted on the rod 82. A crank arm 133 is connected to a bar 128 of the rock frame, and has a rounded head 134 which enters a notch 135 in the plate 113. When the key lever is depressed, the plate 113 is tilted, and the finger 119 falls clear of the bar 64, allowing the platen to be raised by hand. If the key be then released, the finger returns to its original position, and the bar 64 may rest on the finger, thus supporting the platen in its raised position.