Patent GB-770720-A (GB)
Title: Conveyor apparatus
IPC: B65G49/04
Filed: 1955-04-25
Abstract: 770,720. Endless conveyers. STEVENS, Inc., F. B. April 25, 1955 [May 17, 1954], No. 11888/55. Class 78 (1). [Also in Group XXXVI] A conveyer for handling workpieces, e.g. for dipping articles into and conveying them through a succession of electroplating tanks, comprises a plurality of carriages 22 guided for horizontal movement around a central frame, each carriage comprising a vertical fixed guide 140 and a vertically movable slide 143 to which work-supporting means are attached and which is slidable on the guide, the slides being selectively engageable with a horizontal track 106 which is periodically reciprocated vertically. Articles to be electroplated are attached to the work-supporting means, i.e. electrically insulated hooks 149, and by predetermined intermittent movements of the carriages and slides are dipped successively in each of the tanks 170-175, Fig. 4. The carriages are attached to an endless chain 160 and run by means of sets of upper and lower rollers 147, 148 on guide tracks 19, 20 extended around the central frame. The chain 160 runs around sprockets 161, 166, the former being driven intermittently through gearing by a motor 40 controlled by a relay system, not shown. The track 106 extends around the central frame and is mounted on a framework including transverse rods 102, 103, two pairs of which, near opposite ends of the frame are connected by links 72, 73 to tubular braces 71, each of which is secured between opposed elements 70, Fig. 9, of a vertical slide, slidable vertically in a vertical guide 14 consisting of members 60, 63, 70 welded together. These slides are raised and lowered simultaneously by a vertical cylinder 50, whose piston 80 is secured to a frame 81 connected by separately adjustable chains 68 passing over sprockets 89, 67 to the slides. To enable the articles to be dipped for different periods in the respective tanks, the tanks are of different lengths, tanks 170, 174 corresponding to one intermittent movement of the chain 160, tanks 171, 172 to two intermittent movements, and tank 175 to three intermittent movements of the chain 160. To allow articles to remain dipped in the longer tanks 171, 172, 175 while articles are lifted out of the short tanks 170, 174, slides 115-118 are provided in the framework carrying track 106, and are arranged periodically to create and fill gaps 114 in the track 106, the gaps being formed at the desired moments at the beginnings and ends of the tanks 171, 172, 175. Slide 115 operates to open a gap at one side of track 106 and close the gap at the other side and vice-versa, each of the slides 116 and 118 merely opens and closes a gap at one side of track 106, and slide 117 is in two oppositely acting parts 117a, 117b which simultaneously open and close gaps 114 on both sides of the track 106. The slides are operated by cams 111 mounted on a common shaft 110 driven by a double-acting cylinder 130 mounted on the track framework whose piston has a rack 133 engaging a pinion 134 on shaft 110. Cylinders 50 and 130, and motor 40 are controlled by the relay system in conjunction with an electric timer and limit switches operated by dogs on the chain 160 to give the desired sequence of operations. Current is supplied to the hooks 149 only in their " down " positions by a bus-bar extending around the central frame and with which shoes 152 on the slides 143 make contact in their lowered positions.