Patent GB-994739-A (GB)
Title: Improvements relating to glazing installations
IPC: B05C13/02
Filed: 1963-12-18
Abstract: 994,739. Endless conveyers; article engaging devices. AUTOCALORA S.A. Dec. 18, 1963 [Dec. 21, 1962; Aug. 31, 1963], No. 49925/63. Headings B8A and B8H. [Also in Division B2] An installation for coating the insides of hollow metal articles with polymerized glaze, comprises an endless conveyer with supports for the articles, a device for loading the articles on to the supports, a first oven for annealing the metal of the articles whilst conveyed therethrough, a device movable along a part of the path of the conveyer for glazing the interior of the article, a second oven for polymerizing the glazing, a device for unloading the articles and a device for continuously advancing the conveyer, and is characterized in that the glazing device is provided with a coupling device for periodically connecting the glazing device to the conveyer so that it is moved therewith, during application of the glazing, from a first position to a second position at which the coupling device is disengaged from the conveyer, and with return means for returning the glazing device to the first position after disengagement of the coupling device. In the arrangement shown, 1 is an endless chain conveyer for conveying metal tubes to be coated on their inside with a polymerized glaze, 2 is a loading device, 3 a furnace for annealing the tubes, 4 a glazing device, 5 a furnace for polymerizing the glaze and 6 is an unloading device. The conveyer 1 comprises identical carriages 7 articulated to each other by pins 8 and having running elements in the form of two wheels 10 and a ball 11. Each carriage has a plate 12 with straight edges 14 which form carriage guide rails, as described later. Furnaces 3, 5 rest on members 16 and have plane bases 17, 18 which form running surfaces for the carriages through the furnaces, and guide posts 19 for guiding the carriages. Between the furnaces are two straight parts 20, 21 bordered by rows of support rollers 22 the outer ones of which are fixed but the inner ones are movable transversely under resilient means. The rollers 22 are such that they engage the edges 14 of plates 12 as the carriages leave the furnaces to support and guide them over the straight parts 20, 21. The plate 12 of each carriage has spindles 35 rotatably mounted thereon and having baskets 37 (Fig. 4) adapted to support tubes 38 in a vertical position. The furnace 3 comprises a heating tunnel 39 having heating members 40 and baffles 41a, 41b, 41c and 42a, 42b to protect the carriages. The polymerization furnace 5 comprises a similar heating tunnel 43 but with a number of resistors to control the polymerization temperature. A driving motor 44 drives through speed reducer 46, a gear 45 having a double toothed ring which drives an endless chain 48 engaging with abutments on the carriages so as to move the latter around a closed path. The glazing device 4 can be moved between two positions along the straight part 20, coupling means connecting the device to the conveyer periodically for movement therewith and return means being provided for returning it to its initial position on release of the coupling means. These means (Fig. 7) consist of a sole piece 51 on which the glazing device 4 is mounted and which is slidable on rods 52. The coupling means has a lever 53 pivoted at 54 and held in the position shown by spring 55 against pin 56, its other end engageable with pins 58, 58a on the plates 12 of carriages 7 so that when in engagement the sole piece is moved with the respective carriages. The return mechanism consists of lever 59 pivoted at 60, which releases the lever 53 when the end 65 of lever 59 contacts a fixed abutment 66, and a return spring 63. When the end 57 of lever 53 is released from engagement with pin 58 the sole piece 51 and hence the glazing device 4 returns to its initial position; the end 57 is then engaged by the next pin 58a and the sole piece is once again moved with the respective carriage 7. The unloading device 6 can also be moved, between two positions spaced along the straight part 21 by a similar device. The unloading device 6 (Fig. 8) comprises stationary frame 69 having a moving slide 71 thereon connected to a moving sole piece. The slide 71 bears a pivotally mounted cylinder 73 which receives a piston 74. The latter is spring loaded and is air operated by connection to posts 80, 81 and 85 as the slide moves along. The piston rod 75 bears at its lower end a mandrel 76a and a gripper device 76. As the device moves along, starting from position I it first registers with a tube in one of the support baskets 37 (position II), the piston is lowered so that the mandrel 76a enters the tube and gripper 76 is operated to grip the tube (position III), the piston is then moved upwards removing the tube from the basket (position IV), and finally the cylinder is pivoted sideways by cam means (position V), and the tube is released into a receptacle. The unloading device then returns to its initial position to engage the next tube. Cooling air is supplied to the bases of heating tunnels 39, 43 automatically should the conveyer stop so as to prevent overheating of the carriages under such conditions.