ANNULAR PISTON WITH APPLY TUBE FOR HYDRAULIC SERVO MECHANISM OF AUTOMATIC TRANSMISSION

摘要

PURPOSE:To aim at improvement of the fitting accuracy of a sealing member by press-forming an annular piston portion and an apply tube portion integrally and interposing an annular sealing member between a pressure face and the check plate of the sealing member. CONSTITUTION:A piston body 1 consists of an annular piston portion 10 and an apply tube 1A, an annular projection 111 is provided on a pressure wall 11 and the body 1 and the pressure wall 11 is integrally formed by press- forming. The annular outside sealing member 3 is held between the pressure wall 11 and the check plate of the sealing member 2 and has an outer diameter larger than these by a predetermined size, and the annular inside sealing member 4 is held between the pressure wall 11 and the check plate 2 and has an inner diameter smaller than these. Due to like this construction, the fitting accuracy of the sealing members 3, 4 to the piston portion 10 is obtained.