Patent GB-376403-A (GB)
Title: Ink coating machine for the deposition of inks on typewriter ribbon both multi and single colour
IPC: B41J31/14
Filed: 1931-04-22
Abstract: 376,403. Inking typewriter ribbons. STOKES, A. S., 28, Lancaster Road, Leicester. April 22, 1931, No. 11862. [Class 140.] In apparatus for applying ink to multicolour typewriter ribbons of the kind comprising two ink baths, two coaxial ink rolls having a narrow space between them, a thin stationary dividing plate in the space between the ink rolls, and a pressure roll co-operating with the ink rollers, there is provided an adjustable doctor for regulating the amount of ink on the ink rolls, and a thin plate in contact with the doctor and located in or projecting into the space between the ink rolls. The doctor may be slidable towards and away from the ink rolls in intimate contact with a straight top edge of the dividing plate, and the additional plate may be in intimate contact with the edge of the dividing plate in the space between the ink rolls. A blade located in the space between the ink rolls and spring operated to press the ribbon upwardly against the pressure roll may also be provided, The apparatus comprises two side frames 10, Fig. 1, in which are mounted the ink rolls 21 and the pressure roll 19. These rolls are mounted, in bearing blocks 17, 18, Fig. 3, which slide in a slot 14 in each side frame. The ink rolls 21, 22, Fig. 2, are formed with a deep peripheral groove between them, either by the use of two separate rollers, one of which has a short reduced neck, or by turning a deep groove in a single roller. The ink rollers are mounted on a spindle and surrounded by a frame 26, no side play between the rolls and frame being allowed. Attached to the frame 26 are two ink troughs 29, Fig. 1, separated by a thin steel dividing plate 28 which at its upper edge is formed with a semicircular recess corresponding to the diameter of the bottom of the groove between the ink rolls, so that the plate enters between the rolls. A doctor 31, Fig. 2, is mounted on a block 30 adjustable by means of a thumb-screw 32 and sliding in guides on the frame 26. The under surface of the doctor slides in contact with the top edge of the plate 28. The block 30 also carries a thin vertical plate 33 which enters into the groove between the ink rolls and makes contact with the plate 28 and the doctor 31. Ink is supplied to the ink rolls by a roller 34, Fig. 1, in each ink bath, carried on an eccentric mounting adjustable by means of a handle 37. A feed roll 38 is mounted in bearing blocks sliding in slots in the frame, the axle of the feed roll also carrying a belt pulley 39 by which the apparatus is driven and a gear wheel 40 from which the ink rolls 21, 22 and the inking rollers 34 are driven. The ribbon to be inked is carried on a shaft 45, and is led between cleaning brushes 50, 51 and over spindles 52, 53, 54, through the nip between the ink and pressure rollers, over the roll 38 and finally to a winding up shaft 56. In the groove between the ink rolls is located one end of a pivoted blade 60, the other end of which is pressed down by a spring which is adjustable by means of a nut 62. The blade thus presses the ribbon upwardly against the pressure roll 19 in the nip of the rolls, and prevents the inks from creeping across the gap between the inked parts. The shaft 45 is provided with a central enlarged part upon which the bobbin of ribbon is clamped, and means for centralizing the ribbon are provided in the form of a collar at one end of the shaft which enters a groove in a knurled nut working on a screw lying parallel to the shaft 45 and carried on one of the bearings of the shaft. A friction brake is applied to the shaft 45. The ribbon is also centralized by means of adjustable collars on the spindles 53, 54. The winding up shaft 56 is driven by a belt 57 through an adjustable friction clutch which compensates for the increase in the diameter of the roll of ribbon. The pressure roll 19 is pressed down by a lever 93 upon which may be hung weights. A fine adjustment for the spacing of the pressure and ink rolls and for their parallel setting is provided by the means shown in Fig. 3. The under surface of each of the blocks 18 in which the pressure roll 19 is mounted is tapered transversely of the slot 14. Between the block 18 and the bearing block 17 in which the ink rolls are mounted is located a wedge 95, the upper surface of which is tapered and provided with a mortice or key which fits into a slot in the block 18. A screw 97 threaded through the wedge 95 and bearing at each end against the frame permits adjustment of the wedge transversely and consequently fine vertical adjustment of the bearing block. Means are preferably provided for converting the apparatus for the production of single colour ribbons, such means comprising a frame 99, Fig. 1, carrying rollers 103, 104, and an ink pan 106. The pressure roll 19 and the ink rolls 21, 22 are removed, and the roll 19 is placed, with its adjusting mechanism and weighting lever 93, in position above the roll 38. The shaft 45 is placed in the bearings of the spindle 52. From this the ribbon is led downwardly and around the roll 103, between that roll and the roll 104, over suitable guides, between the roll 38 and the pressure roll, and wound on the spindle 56. In an alternative arrangement for supplying the inks to the double ink roller, one roll 21, Fig. 9, is located on each side of a fixed dividing plate 128. A second pair of rolls 110, parallel to the first pair, and rotating in contact therewith form with the first pair two troughs in which ink is held. The dividing plate 128 extends above the ink rolls and is formed at its upper edge with a radiused part which conforms to the periphery of the pressure roll 19 and presses against the ribbon 47.