GB959138A - Improvements in or relating to master cylinders for liquid pressure operating systems - Google Patents

Abstract

959,138. Master cylinders. AUTOMOTIVE PRODUCTS CO. Ltd. March 14, 1963 [March 27, 1962], No. 11725/62. Headings F2F and F2L. The axial retractive movement of a spring-loaded piston 16 towards the open end of a master cylinder 10 in a hydraulic brake or clutch control for a motor-vehicle, is limited by a stop formed by an internal flange 27 at one end of a resilient metal sleeve 28 which is split longitudinally from its other end to provide a number of fingers 29, each being bent to form an external, or internal, projection 32 to engage in an internal, or external, groove 34 in the master cylinder, the fingers being inwardly, or outwardly, deformable to enable the projections 32 to pass into, or over, the master cylinder and snap into the groove 34 therein. As shown, the projections 32 also serve to locate a piston bush 21 and seal 19 and the sleeve 28 is additionally formed with a second set of shorter fingers 31 outwardly bent to provide projections 33 which retain a flexible sealing boot 35 over the open end of the master cylinder 10, a liquid reservoir 12 being secured to the cylinder by a spring clip (Fig. 2, not shown). In Fig. 6 (not shown) a similar arrangement is provided except that all the stop sleeve fingers are of equal length and bent outwardly for engagement in the common internal retaining groove in the cylinder, the flexible boot being snapped directly into an external groove at the open end of the cylinder. In Figs. 4 and 5 (not shown), the stop sleeve is formed with inwardly bent fingers which engage in a common external retaining groove on the cylinder with the flexible boot engaging over the sleeve, the piston bush and seal being retained by a snap-ring in the cylinder on which is brazed a sheet-metal liquid reservoir can. In all the above arrangements, a push-rod 25 is retained in a bore 24 in the outer end of the piston 16 by a second resilient metal sleeve 37 (Figs. 7 and 8, not shown) which has an internal flange engaged behind the part-spherical pushrod head 26 and is split longitudinally to form two arcuate fingers which are outwardly deformed to locate and retain the sleeve in a groove 43 in the piston bore 24.