Patent GB-1448815-A (GB)
Title: Locating or gauging apparatus
IPC: B23D33/10
Filed: 1972-08-11
Abstract: 1448815 Gauging stops G W WYNN 9 Nov 1973 [11 Aug 1972] 37529/72 Heading B3W Apparatus for locating or gauging the position of a workpiece comprises an interconnected series of pivotable elements arranged in a line on a support, chosen elements being selectively pivotally displaceable transversely of the line to provide an abutment or other indicator of a distance longitudinally of the series from a predetermined point on the support. As shown, Fig. 1, gauging stops 18 are mounted on links 10 pivoted to link 12 by pins 14 and the pair of links 10, 12 is pivoted to adjacent pairs at 16. Extensions (30) Fig. 2 (not shown) of the pins 14 allow a selected stop 18 to be raised to vertical position in which the rear edge of the raised link 10 is braced against the leading edge of the following link 10. A member 20 at the front of the chain 4 of links 10, 12 is urged against a stop 24 on a fixed part 48 of a machine by a piston 26 urged by a spring 28 against a rear member 22. The stop 24 is movable longitudinally for fine adjustment of the position of the selected gauging stop by means of a screw stem 42 and the stop 24 and a graduated scale 50 can be pivoted to allow the stop to be re-set once a gauged workpiece has been clamped. In setting up the selected gauging stop, the stop 24 is moved to its furthest left position, as viewed in Fig. 1, the selected stop is raised and also a stop rearwardly of it to relieve the selected stop of the pressure of the spring 78. The stop 24 is then adjusted if necessary. The second raised stop is lowered and the spring urges the chain against the stop 24. For more accurate setting the stop 24 acts on an auxiliary device 56 having stops 58 spaced by the length of a pair of links and resilient means act on the front member 20 of the chain to draw the selected gauging stop 18 against a stop 58. In a further embodiment, Fig. 3, a selected gauging stop 92 is raised by engagement of a spur 94 on the relevant link 80 with a cam 104 on a shaft 102. The spurs 94 of a first group of link pairs 80, 82 are laterally spaced from those of a second group and so on along the length of the chain. Cams 104 equal in number to the number of spurs in each group are spaced radially and longitudinally of the shaft 102. The shaft is displaceable laterally, by means of a lever 134, to align it with different groups of spurs and rotatable, by means of a lever 140 and chain and ratchet mechanism 142. In use, with the shaft in the selected position the relevant cam lies in the path of the spur associated with the selected gauging stop and as the chain is advanced, i.e. moved to the left, Fig. 1, the selected link 80 is raised. For finer adjustment of the gauging stop position, an adjustable rigid stop (not shown) similar to the stop 24 is provided at the front of the chain and is held in place by a master hydraulic cylinder (not shown) connected to a slave cylinder 110. The piston 112 of the slave cylinder is biased inwardly against fluid pressure by a spring 114 and the displacement of the piston 112 against the spring 114 determines the axial displacement of the stop associated with the master cylinder. The displacement of the piston 112 is controlled by engagement of a selected one of gauging bars 116 axially slidable in a rotatable barrel 118 with a rotatable disc 122 which is either stepped or of continuously variable thickness. A spring 126 urges the disc against a fixed stop 124. In use, hydraulic pressure supplied to the cylinder 110 urges the piston 112 against whichever gauging bar is aligned with it, the gauging bar and gauging disc being gripped between the piston 112 and the stop 124. This limits the displacement possible for the stop (not shown), associated with the master cylinder, at the front end of the chain so that with the chain urged against this stop the position of a selected stop 92 is determined by the length of the selected gauging bar and the thickness of the portion of the disc which it engages. The stop 124 may be threaded to provide further fine adjustment. Elements such as spring loaded detents (not shown) may help to bring index rings, indicating the adjustment of the shaft 102, the gauging bars and the disc, to specific settings. Work supporting rolls 100 may alternate with gauging stops and each link may comprise a double plate. The links 80, 82 run on rolls (98) in parallel tracks (96), Fig. 4 (not shown). The device 56 may be associated with the Fig. 3 embodiment. Damping or drive means may restore a gauging stop to its proper position after the impact of a workpiece. Lateral work guides may be provided. Two gauging chains may be used side by side. Workpieces can be raised by the raising of several gauging stops. The gauging stops may be replaced by visible indicators. The operation of the stops can be controlled using punched cards or a computer.