| 摘要 |
PURPOSE:To enable the ratio of the rotational speed of an impeller to that of a turbine to be controlled to a given value and to improve a torque transmission efficiency, by installing a slip control valve which controls the oil pressure in a release chamber partitioned within the shell cover of a torque transmission device. CONSTITUTION:When a vehicle starts, the spool 68 of a slip control valve 60 is moved rightward by operating a pulse motor 62 by means of a computer 61 to communicate a port 66b with a port 66c. This enables the same oil pressure as that in any apply chamber 48 to be fed to a release chamber 46, and brings a friction clutch piston 10 into release state. Under normal running condition, the spool 68 is then brought to a position as shown in the drawing, and by draining a slight quantity of the oil through the port 66a, the oil pressure in the release chamber 46 is lowered below the oil pressure in the apply chamber 48. In which case, a difference in the rotational speed between input and output shafts 15 and 38 is calculated by a computer 61 from the outputs of input and output rotational speed detectors 72 and 74, and based on the output of the calculated result, the position of the spool 68 is controlled through the pulse motor 62. |
