Patent GB-867099-A (GB)
Title: Marking machines
IPC: B41F19/06
Filed: 1957-09-23
Abstract: 867,099. Marking tubes. DUBUIT, L. G. Sept. 23, 1957 [Nov. 20, 1956]. No. 29874/57. Class 100(2) In a machine for applying marks at intervals on a long, continuously moving object, e.g. a tube, a printing block and an impression block are mounted respectively on two trolleys each of which is horizontally slidable on one of two further trolleys which are slidable vertically on the machine frame so as to grip the moving object between the printing and impression blocks for printing, the horizontally slidable trolleys moving with the object as it is being printed. The tube 9 to be printed is gripped between a rubber-covered roller 3 keyed to a shaft 2 and a metal roller 8 having a V-shaped peripheral groove, and is moved continuously in the direction of the arrow f, by means not shown, so that the rollers 3, 8 and shaft 2 are rotated. The shaft 12 driven by the tube serves as a main shaft for driving the various parts of the machine. Two trolleys 11, 12 are slidable on vertical slides 10 on the machine frame and respectively carry two further trolleys 17, 18 which are slidable horizontally thereon. The trolley 17 supports an engraved printing block 23 and has an electric resistance 24 controlled by a thermostat 25 for heating the block, while the trolley 18 carries an impression block 30 having a grooved upper face. A member 19 rigidly fixed to the trolley 17. slidably engages a mortice in the trolley 18 so that the two trolleys move horizontally in unison. The trolley 11 is coupled by a rod 13 to the core of an electromagnet 14 which when energised raises the assembly 11, 17, 23 on the slides 10 and when de-energised lets the assembly fall under its own weight to printing position, the fall being damped by two springs 27 the tension of which is adjustable. The trolley 12 rests on the upper end of a screw 15 whereby the assembly 12, 18, 30 may be vertically adiusted to allow for varying thicknesses of objects to be printed. The roller 8 is vertically adjustable for the same purpose. A band of paper 46 coated on the underside with a layer of thermofusible material is fed from a reel 44 round rollers 47, 48, passing between the block 23 and tube 9, round a pressure drum 49 and on to a take up core 50, the roller 48 being driven continuously from the shaft 2. The coating is transferred to the tube, where it is pressed against it by the heated block 23. If the tube is of plastic material the impression may be in intaglio owing to a local melting of the material. A cranked arm 32 is pivoted to lugs 31 on the trolley 17 and a slot 32a therein slides on a guide 35 through which passes the shaft 2. The free end of the arm 32 carries a roller 34 which engages a cam 36 keyed to the shaft 2 this cam serving to return the trolleys 17, 18 to starting position after an impression has been made. An arm 39 pivoted to the machine frame at 40 carries a roller 38 which engages a disc-cam 37 also keyed to the shaft 2 and including a cut-out portion 37a which may be adjustable in length on its periphery. A feeler 41 on the arm 39 engages the push-rod of a contact-maker 42 to close the circuit of the electromagnet 14 when the roller 38 engages the projecting portion of the cam 37, the trolleys 11, 17 thus being held in the raised position. The circumference of the roller 3 is equal to the spacing of the printed marks required on the tube so that one impression is made for every revolution thereof. The relative angular disposition of the cams 36, 37 on the shaft is such that as the roller 38 falls into the cut out 37a, thus breaking the electromagnet circuit and letting the assembly 11, 17, 23 fall to make an impression, ths cam 36 reaches the position in which it no longer pushes back the cranked arm 32 towards the left (Fig. 1) and the roller 34 fails into the hollow of maximum depth of the cam. Thus the trolleys 17, 18 are free to travel with the tube whilst making the impression, until the roller 38 rides out of the cut-out 37a, closes the electromagnet circuit and raises the assembly 11, 17, 23, at which point the cam 36 begins to push the cranked arm 32 back towards the left. Increased pressure may be applied to the block 23 by use of a second electromagnet. In a modification the assembly 12, 18, 30 is also made vertically reciprocable during operation so that the blocks 23, 30 move together and apart simultaneously. In a further modification, Fig. 4 (not shown), the movements of one or both vertical trolleys are effected mechanically by linked levers controlled by the arm 39.