| 摘要 |
1,164,507. Welding guns. BUDD CO. 10 March, 1967 [15 March, 1966; 9 Aug., 1966; 15 Dec., 1966], No. 11437/67. Heading B3R. A welding gun pivotable from an inoperative position to an operative position, comprises a fixed mounting bracket 10, a guide bar 12 slidable in the bracket, and a yoke 18 pivoted to the bar at 20, which carries a first electrode 64, a double-acting fluid pressure cylinder 22, and a piston-rod 26 carrying a cam bar 32 and a second electrode 62. Bar 12 slides on rollers 14, 16 mounted in bracket 10, and supports rollers 44, 46 which co-operate with cam bar 32, the latter being slidable on rollers 38, 40 journalled in yoke 18. An arm 58 on cam bar 32 cooperates with an adjustable stop 60 on bracket 10, and a second stop 80 on the bracket co-operates with a screw 78 on bar 12. In operation, fluid is supplied to cylinder 22, and rod 26, along with cam bar 32, move downwardly so that roller 44 moves from surface 50 on to surface 54, and thence on to surface 48, and roller 46 moves from surface 52, on to surface 56, and thence on to surface 50 of the cam, and yoke 18 is pivoted into a vertical position. Further movement of rod 26 moves electrode 62 into contact with the workpiece 82 as arm 58 contacts stop 60, thus limiting downward movement of the cam. Continued supply of fluid causes cylinder 22 to move relative to rod 26, whereby the yoke 18 and bar 12 are moved upwardly, so that screw 78 is moved away from stop 80, thus moving electrode 64 into contact with the workpiece. After welding, fluid is supplied to the other end of cylinder 22 and therefore this pressure, along with the action of a spring (74), Fig. 1 (not shown), moves the yoke 18 and bar 12 downwardly, to move the electrode 64 away from the workpiece, until screw 78 contacts stop 80. Further application of fluid pressure produces an upward thrust of rod 26, and cam bar 32 moves upwardly so as to tilt the gun into its inoperative position. Each electrode is water cooled, and spring (74) partially counterbalances the weight of the yoke, when the gun is used in an inverted position. |
