Patent GB-159378-A (GB)
Title: Improvements in and relating to dividing machines for glass tubes rules and the like
Inventor: ROOKER FRANCIS JOHN
Filed: 1919-12-17
Abstract: 159,378. Rooker, F. J., and Munro. Ltd., R. W. Dec. 17, 1919. Dividing-engines.-Relates to a machine for marking graduations on glass tubes, &c., and having a scriber adapted to receive an intermittent traversing movement alongside the tube on which the main divisions are already marked. In order to allow for variations in the bore of the tube, as represented by varying distances between main divisions, means are provided for moving the scriber relatively to its carriage as required to ensure that the scriber at the end of its travel over a main division shall coincide with the terrninal graduation of that division. The tube 1 is supported between a tailstock 2 and headstock 3 carried by a frame 97 having guides 5 along which a main carriage 4 is adapted to be traversed. An auxiliary slide 7 carried by the carriage supports a further slide 8<1> having a vertical guide 8 in which a block 9 is adjustably mounted. The scriber 11 is carried by an arm 10 pivoted to the block and is operated by a Bowden wire 18. The slide 8<1> can be adjusted over the slide 7 by a screw 39 and clamped by a screw 41. Uprights 19, 20 carried by the frame 97 support a guide-bar 21 carrying a number of brackets 22 through which pass rods 24. Each rod is threaded at its upper end to allow of vertical adjustment by a screw 25, and at its lower end has a split boss 26 in which is rotatably mounted a slotted cylinder 27. A flexible steel band 33, secured at its ends to clamps 98 carried by the uprights, passes through all the cylinders, in which it is held by gripping-members, and also passes between rollers 36 at the end of one arm 37 of a bell-crank lever pivoted to the carriage 4. The arm 38 of the lever engages an extension 7<1> of the slide 7 which is consequently moved in relation to the carriage 4 according to the shape to which the band 33 is set. The driving-shaft 42 carries, at the headstock end, an eccentric 54 connected to a plate 49, Fig. 5, having pins 50 passing into slots 51 in the forked end 47<1> of an arm 46 pivoted to a bracket 45 secured to the frame 97, the plate being held in engagement by two springs 52. The headstock carries two parallel shafts 55, 56 connected by gears 57, 58, the shaft 55 also carrying a pinion 48 gearing with the sector 47 on the arm 46. The tube 1 is gripped by a chuck 99 on the shaft 56, which also carries a grooved cam 59 adapted to oscillate a lever 60, having at its lower end a pawl 61 operating a ratchet-wheel 62 on a shaft 63 passing through the headstock. At its other end the shaft 63 carries a disc 64 having two slots 65, 66 of different depths and co-operating with a projection 67 on a pivoted arm 68 which is held up by a spring 71 and has a projection 72 which registers with one of three discs 73, 74, 75, secured to the shaft 56, according to the position of the disc 64. These discs control the amplitude of oscillation of the tube 1 and consequently the lengths of the graduation marks, disc 75 being plain to allow a complete circle for the main divisions and discs 74, 73 having stops to limit respectively the lengths of the central subdivisions and the remaining graduations. The carriage 4 is traversed by a lead-screw which is operated by a wheel 80 gearing through a changewheel 81 with a wheel 82 on a shaft 83 to which is also secured a ratchet-wheel 85 operated by a pawl 86 on a pivoted arm 87 which is connected by a rod 88 to a pin 89 on a disc 90 secured to the shaft 42. The shaft also carries a cam 76 operating a pivoted arm 77 to which the end of the Bowden wire is secured. A wheel 91 on the shaft 83 operates a wheel 92 connected to a counter 95. In using the machine, the band 33 is adjusted by the screws 25 until the scriber registers correctly with the main divisions; the spacing of the sub-divisions is then automatically adjusted by the motion of the bell-crank lever due to the passage of the rollers 36 along the band.