GB629361A - Improved lifter jack for motor vehicles and the like - Google Patents

Abstract

629,361. Lifting jacks. GENERAL MOTORS CORPORATION. May 19, 1947, No. 13371. Convention date, June 10, 1946. [Class 78 (iii)] A screw 40, Fig. 1, and a nut 87, having antifriction balls 91 therebetween, are located within a column 17 which has a slot 19 through which projects both a radial pin 99, secured to the nut, and a load engaging hook 103 having a part spherical surface 101 which engages a similar surface on said nut and arcuate lugs 109, 113 which respectively engage the interior and exterior surfaces of the column. The column is secured in a cup 15 in the base by engagement of a spring 23, carried by the column, with a detent 151 on said cup which projects through the slot 19. An arm 53 and a handle 75, both of which may be folded to lie parallel 'with the column, are operatively connected with a cap 51, Fig. 5, which, together with a ratchet 49, is non-rotatably mounted on an extension of the screw 40 which also passes freely through an annular pawl 39, a ball race 33, 35, 31, a cap 25 and a spring clip 69, lugs 41 on said pawl 39 co-operating with notches 43 in the bearing cup 31 the partspherical lower surface of which nests in a similar surface formed in the cap 25. Rotation of the screw 40 is assisted by the bearing 33, 35, 31 until the hook 103 engages a load which, in tending to rotate the screw in a reverse direction, engages the ratchet 49 with shoulders 45 on the pawl 39 and so locks the cup 31 to the screw 40 and renders the ball race inoperative so providing sufficient friction between the cup 31 and cap 25, which now constitute the bearing, to prevent overhauling.