HYDRAULIC CIRCUIT FOR CONTROLLING AUTOMATIC TRANSMISSION GEAR

摘要

PURPOSE:To reduce the shock due to speed change shifting by controlling the state of the intercommunication of a primary port for intercommunicating an accumulator control means to the control oil source and a secondary port for intercommunicating the accumulator control means to an accumulator back pressure chamber, in response to the control position of a shifting control means. CONSTITUTION:An accumulator control means 70 is provided for controlling the back pressure of an accumulator. The hydraulic circuit is provided with a primary port for intercommunicating the accumulator control means 70 to a control oil source and a secondary port for intercommunicating the accumulator control means 70 to accumulator back pressure chambers 59, 60, 61 and is controlled by a hydraulic pressure through a shifting control means 51. Therefore, it is possible to adjust the accumulator property in response to the speed change position and ensure the suitable accumulator capacity.