Patent GB-660248-A (GB)
Title: Improvements in or relating to the polishing of glass
Inventor: LAVERDISSE EDMOND
IPC: B24B7/24
Filed: 1949-03-21
Abstract: 660,248. Polishing glass. GLACERIES DE LA SAMBRE SOC. ANON. March 21, 1949 [March 27, 1948; March 1, 1949], Nos. 7672/49 and 7673/49. Class 60 A process for simultaneously polishing both faces of a.continuously moving glass band or sheet 1 is characterized in that during the polishing operation the tools or the sets of tools 3, 5 on each side of the glass travelling in a substantially horizontal plane are reciprocated transversely of the path of the glass, any tool or set of tools on one side of the glass moving in opposite direction to the co-operating tool or set of tools on the other side of the glass. The tools, which may be in the form of blocks or rotatablydriven discs, are secured to beams 4, 6 carried on frames 13, 14, Fig. 2, which are traversed in contact with one another in the same direction as the glassby means of a rack 16 and a gear wheel 17 on rails 15. The tools 5 act on the upper surface of the sheet, while the tools 3 act on the lower surface. The reciprocating motion is obtained by connecting the beams 4, 6 to cranks 20, 21 which are in anti-phase and connected by a synchronizing chain 24, the drive being from a motor 22 through a reducing gear 23. Pressure between the tools and work is governed hydraulically, each tool being provided with a hydraulic piston and cylinder equipped with a spring which biasses the tool away from the work and connected by conduits 34, 35 with a motor-driven pump 33. A second motor-driven pump 28 supplies an iron oxide polishing composition to the tools through conduits 29, 30. Each frame 13, 14 is provided with collectors in contact with bus bars 79 supplying the motor 22 and the pump motors, and is traversed at the same, or a faster or slower, speed than the glass. When a frame reaches the end of its traverse, the collectors engage a separate set of bus-bars connected to the supply by a biassed switch which is operated by a downwardly-projecting abutment on the beam 4 as the frame advances on to the separate set of bus-bars thereby interrupting the supply to the pump-motors and the motor 22, the abutment being so positioned that the beams are stopped in a central position. The frame is now engaged by a dog on a rapidly-moving chain 42 so that it is traversed on to a downward lift 7 which is set into operation by the contact of the frame with a switch 87, the beam 6, which rests on pins 51 on the frame during operation, being supported by a bar 44 in hooks 43 on an upward lift 9 which is similarly set into operation by contact of the beam 6 with a switch (not shown). The conduits 30, 35 are closed by valves and manually disconnected from their respective pumps before the beams 4, 6 are separated. When the lift 7 descends, the frame 13, 14 is picked up by a roller chain 8 and in this process it operates a switch 88 which returns the lift in readiness to receive the next frame. The beam 6 is similarly picked-up on a roller chain 10 after it has been lifted by the arms 57 of the lift 9, a switch being closed as the beam is deposited on the rollers to reverse the motor driving the arms 57. As the arms 57 start their return swing the hooks 43 are tilted by a spring compressed at the end of the upward movement to free the bar 44. At the end of the return traverses of the frame 13, 14 and the beam 6, assembly is effected by similarly-operated lifts 11, 12 and the frame is traversed by a dog on a rapidly moving chain 53 until it is engaged by a lever 54 which is rocked against a spring 55 by a rotating cam 56 to push the frame into contact with the preceding one, whereupon the rack 16 is engaged by the gear 17 to impart forward movement to the abutting frames. Hydraulic means may be used to reciprocate the beams 4, 6. Each frame is fitted with a freely-rotatable roller 40 to support the glass.