GB1293646A - Improvements in or relating to polishing machines - Google Patents

Abstract

1293646 Polishing WILMOT-BREEDEN Ltd 26 May 1971 [4 June 1970 28 Nov 1970] 26942/70 and 56665/70 Heading B3D A polishing machine comprises a track 11, Fig. 1, a carriage 13 having a mounting for a workpiece support and movable along the track past a polishing station A, B ... T, drive means 22 operative to move the carriage along the track, and a control member 25 connected to means 32 for producing appropriate movement of the workpiece support at a polishing station, the control member when moving at the same speed as the carriage resulting in the workpiece support remaining stationary relative to the carriage but when moving at a differential speed, resulting in controlled movement of the support on the carriage. The track has two parallel sections 11 joined by end-sections 12 and consists of spaced parallel members 14 on which run rollers 16 at the corners of the carriage. A plurality of carriages are provided spaced by a distance equal to the spacing between the polishing stations. Stations A to P consist of abrasive belts running over rollers 48, 49, 50 and a contact roller 52, and stations Q to P consist of rotary polishing mops. One end of the track has a drive means 18 consisting of a chain wheel 19 which is keyed to a shaft 20 and engaged by the drive means in the form of a chain 22 connected to each carriage, the shaft 20 being coupled to an hydraulic drive motor 23. A second chain-wheel 24 is rotatably mounted on the shaft 20 and is engaged by the control member 25 in the form of a second chain 25. The wheel 24 is secured to a plate 29 which is rotatable on the shaft and connected by hydraulic rams 28 to a plate 27 secured to the shaft 20, actuation of the rams causing movement of the chain wheel 24 relative to chain wheel 19, and hence movement of the control chain 25 relative to the drive chain 22. Each carriage has a workpiece support shaft 33 which is rotatable in a bearing structure 34 and carries a workpiece, such as a bumper bar of a vehicle. A lever 32 is secured to the shaft 33 and has a pair of arms 36 formed with slots 37 receiving rollers 38 projecting above and below the control chain which is guided by strips 40, 44. An encoder 46 driven from an idler sprocket 47 controls the rams 28 so that the control chain 25 moves relative to the drive chain to move the shaft 33 carrying the workpiece with an appropriate movement as it passes each polishing head. The heads are movable towards and away from the track under the control of the encoder. In another embodiment, the lever 32 for moving the workpiece is replaced by a sprocket coupled to a gear on the workpiece support.