Brake shoe assembly

Claim 1

In a brake shoe assembly for use in cylindrical automotive brake drums in hydraulic brake systems including a pair of brake shoes, a common hydraulic brake wheel cylinder having opposed actuating pistons, and actuating pins extending between abutting surface portions of the pistons and associated brake shoes, the improvement comprising, a spheroidal, concavely-rounded end surface formed at the piston end of each of the actuating pins and complementary protrusions at the outer ends of each of the hydraulic cylinder actuating pistons for face-to-face sliding abutment contact with said concavely-rounded end surfaces, said actuating pins being of unitary, integral construction, each of the brake shoes being integrally formed with a substantially flat, arcuately-bent brake lining support plate portion of uniform thickness and a web portion of substantially greater uniform thickness extending centrally outwardly of and along the inside of said arcuate support plate portion, each of said actuating pins, at their brake shoe ends, having a sphereoidal, convexly-rounded end surface, said web portions of each of said brake shoes being integrally formed with a sphereoidal concavity for face-to-face sliding abutment contact therewith of said convexly-rounded end surfaces of said actuating pins.