Patent GB-971146-A (GB)
Title: Apparatus for sanding vehicle bodies
IPC: B24D13/04
Filed: 1963-07-23
Abstract: 971,146. Abrading. MERIT PRODUCTS Inc. July 23, 1963 [July 25, 1962], No. 29193/63. Heading B3D. Apparatus for treating the surfaces of vehicle bodies as they progress along an assembly line comprises one or more rotatable abrasive drums constructed from a plurality of radial, flexible, abrasive coated fingers or leaves arranged adjacent the assembly line with the drum axes transverse to the direction of motion of the bodies. The vehicle bodies are conveyed past the apparatus by chains 20 and have upper surfaces 22, 23 and side surfaces 35, 36, 38 which are abraded by an upper drum 27 and side drums 45, 46, 48. The upper drum 27 is rotatably supported on bell-crank levers 30 pivotally mounted on arms 28 in turn mounted on pivots 20 on a frame 60, the bell-cranks being movable by fluid pressure piston-and-cylinder devices 31 to raise and lower the drum 27 between operative and inoperative positions and the arms 28 being movable by fluid-pressure piston-and-cylinder devices 29 to move the drum from a position for abrading the roof surface 22 of the body to a position for abrading the deck surface 23. The actuation of the devices 29, 31 is controlled by valves 86, 92 controlled by feelers, the circuit including timers which act to delay the engagement of the drum with surfaces so that the leading edges of the surfaces are not excessively abraded. The surfaces 35, 36 of the body, which are continuous, are abraded by the drums 45, 48 which are belt-driven from motors 155 and supported for rotation in bearings 144, 154 in the frame 60. The surface 38, however, is interrupted by the wheel arch 40 and to avoid excessive abrading of the leading edges 42, 43 the drum 48 for abrading the surface 38 is mounted on a yoke rockable about pivots 160 on the frame by a piston-and-cylinder device 50 controlled by a valve 170 actuated by a feeler 52, a timer being incorporated in the circuit to delay movement of the drum after actuation of the feeler so that the leading edges are not excessively abraded. In an alternative embodiment, the drums 45, 46, 48 are moved into engagement with the surfaces 35, 36, 38 under the control of feelers acting on the opposite side of the vehicle, that side then being abraded by feelers acting on the first side, such an arrangement not necessitating the use of timers. The lengths of the rods 88, 166 of the piston-and-cylinder devices 29, 50 are adjustable by oppositely-threaded sleeves 214, 215 to compensate for the reduction in size of the drums as they wear. Each drum comprises a hub portion 192, Fig. 8, having radially-extending slots 194 formed with enlargements 195. Each slot receives a disposable element consisting of a base part 204, Fig. 9, having an enlargement 206 for engaging a slot 194 and enlargement 195, and a plurality of abrasive coated sheets 198 secured by a staple 205 to the base part. The sheets are arranged with the stronger warp threads 208, Fig. 12, extending across the sheet so that, as the abrasive coating is eroded from the tips of the sheets and the weft threads 210 wear away, the warp threads readily unravel and drop away.