GB1231921A - - Google Patents

Abstract

1,231,921. Conveyers. HOOKER CHEMICAL CORP. 24 July, 1969, No. 37193/69. Heading B8A. In a machine having work carriers which travel in a closed circuit, Fig. 1, a number of stations for treating workpieces in liquid have selectively operably devices for providing skip operation, delayed setdown or early pick up of the workpieces. Skip tracks ST1, ST3 permit selected carriers to omit anodic cleaning treatment at stations S2 and S8-S11, while tracks ST2, ST4 permit skipping of acid pickle stations S4-S6 and S13. Early pick up of carriers which have passed through electroplating stations S15-S21 is provided by track ST5 and delayed setdown is provided by devices 22 at stations S29 and S31. Work carriers 52 are guided and supported in horizontal tracks 58, 62 which carry roller chains 68 secured to each carrier, the weight of the carrier being carried by low-friction elements 74 which slide on the track 62. The chains are driven intermittently by gear and motor means 90, 92. Each carrier incorporates a vertically movable work carriage 94 provided with self-lubricating slide members 98 which also electrically insulate the carriage from the remainder of the machine. A work supporting arm 100 is provided with an electrical conductor 104 having a collector shoe 110 for engagement with a bus-bar 112. The conductor may be insulated from the arm 100. An elevator chassis 34 for the carriers 52 comprises a pair of longitudinal members 44 suspended on chains 32 operated by a pistoncylinder unit 36. Each work carriage 94 has an arm 118 which, when the chassis 34 rises, is engaged by a lift pad 120, provided on the chassis. To maintain the lift pads in engagement with the members 118 when the carriers 52 are advanced, the pads 120 are mounted on slide plates 122 connected by roller chains 150, Fig. 4, one of the plates being reciprocated by a cylinder (142), Fig. 9 (not shown). Skip operation.-Assuming a rail section 134 of track ST5 is in the position shown in phantom, Fig. 13, an arm 128 on the carriage 94, when the latter has completed an advancing movement, is supported by the rail section 134 and the carriage remains in the elevated position while supported by the track ST5. With the section 134 raised, the carriage remains supported by the lift pad 120 and normal operation continues. A delayed setdown device comprises a pistoncylinder 158, 156 which, when extended, engages the arm 118 of a carriage to retain the carriage in the raised position, retraction of the piston under the control, for example, of a timer mechanism, then allowing the carriage to be lowered. Early pick up means consists of an auxiliary slide plate 160 which overlies the principal slide plate 122, Fig. 11, and is selectively movable to an operative position by a cylinder (166), Fig. 10 (not shown). A lift pad 164 is attached to the plate 160. In a modification, the motor drive 90, 92 is dispensed with and the transfer movement of the work carriages is achieved entirely by the reciprocating movement of the slide plates 122.