HYDRAULIC CONTROL SYSTEM OF A TRANSMISSION WITH AN ACCUMULATOR FOR ABSORBING HYDRAULIC SHOCK AND PRESSURE SURGE OF HYDRAULIC OIL INTRODUCED FROM A MAIN LINE TO EACH BRANCH LINE

摘要

PURPOSE: A hydraulic control system of a transmission is provided to prevent the pressure of a clutch from increasing suddenly by hydraulic shock and pressure surge of hydraulic oil and accordingly to restrict shift shock caused by the sudden rise of the clutch pressure. CONSTITUTION: A hydraulic control system of a transmission is composed of a hydraulic pump(10) having a main line(20); first, second, third, and fourth branch lines(28a,28b,28c,28d) branched off from the main line and connected with forward 1 and 2-stage clutches(29a,29c) and reverse 1 and 2-stage clutches(29b,29d), respectively; forward 1 and 2-stage solenoid valves(30a,30c) and reverse 1 and 2-stage solenoid valves(30b,30d) for shutting off or opening four branch lines, respectively; a first bypass line(40a) branched off from the first branch line to bypass the hydraulic oil passing through the forward 1-stage solenoid valve; a second bypass line(40b) branched off from the second branch line to bypass the hydraulic oil passing through the reverse 1-stage solenoid valve; a third bypass line(40c) branched off from the third branch line to bypass the hydraulic oil passing through the forward 2-stage solenoid valve; a fourth bypass line(40d) branched off from the fourth branch line to bypass the hydraulic oil passing through the reverse 2-stage solenoid valve; and a plurality of accumulators for storing temporally the hydraulic oil introduced to four bypass lines to prevent pressure of each branch line from rising suddenly as each solenoid valve opens four branch lines, respectively.