Hydraulic control apparatus for automatic transmission
First Claim
1. A hydraulic control apparatus for an automatic transmission which supplies a controlled hydraulic pressure, which is generated by regulating a line pressure supplied from a hydraulic pressure source, to an engagement element, comprising:
- a control valve unit including;
a line pressure input port to which the line pressure is inputted;
an output port for outputting the controlled hydraulic pressure;
a spool housed in a valve body so as to slide therein and for selectively opening and closing the line pressure input port and the output port;
a spring for biasing the spool in one direction;
a feedback hydraulic chamber introduced with the controlled hydraulic pressure and operated to push the spool in a biasing direction of the spring;
a pilot pressure chamber filled with a pilot pressure and operated to push the spool against a biasing force of the spring;
a pilot pressure control device for controlling the pilot pressure in the pilot pressure chamber;
a sleeve provided at an opposite side of the spring relative to the spool;
a plunger positioned inside of the sleeve so as to slide therein; and
at least one plunger hydraulic chamber for pushing the plunger when the controlled hydraulic pressure is introduced therein so as to push the spool in a direction against the biasing direction of the spring; and
a switching device provided at a hydraulic passage between the output port and the plunger hydraulic chamber and for selectively establishing a communication between the output port and the plunger hydraulic chamber.
1 Assignment
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Accused Products
Abstract
A hydraulic control apparatus for an automatic transmission which supplies a controlled hydraulic pressure to a engagement element includes a control valve unit including a line pressure input port, an output port for outputting the controlled hydraulic pressure, a spool for selectively opening and closing the line pressure input port and the output port, a spring for biasing the spool in one direction, a feedback hydraulic chamber, a pilot pressure chamber, a pilot pressure control device, a sleeve, a plunger positioned inside of the sleeve, and at least one plunger hydraulic chamber for pushing the plunger when the controlled hydraulic pressure is introduced therein so as to push the spool in a direction against the biasing direction of the spring. The hydraulic control apparatus further includes a switching device provided at a hydraulic passage between the output port and the plunger hydraulic chamber and for selectively establishing a communication therebetween.
19 Citations
20 Claims
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1. A hydraulic control apparatus for an automatic transmission which supplies a controlled hydraulic pressure, which is generated by regulating a line pressure supplied from a hydraulic pressure source, to an engagement element, comprising:
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a control valve unit including;
a line pressure input port to which the line pressure is inputted;
an output port for outputting the controlled hydraulic pressure;
a spool housed in a valve body so as to slide therein and for selectively opening and closing the line pressure input port and the output port;
a spring for biasing the spool in one direction;
a feedback hydraulic chamber introduced with the controlled hydraulic pressure and operated to push the spool in a biasing direction of the spring;
a pilot pressure chamber filled with a pilot pressure and operated to push the spool against a biasing force of the spring;
a pilot pressure control device for controlling the pilot pressure in the pilot pressure chamber;
a sleeve provided at an opposite side of the spring relative to the spool;
a plunger positioned inside of the sleeve so as to slide therein; and
at least one plunger hydraulic chamber for pushing the plunger when the controlled hydraulic pressure is introduced therein so as to push the spool in a direction against the biasing direction of the spring; and
a switching device provided at a hydraulic passage between the output port and the plunger hydraulic chamber and for selectively establishing a communication between the output port and the plunger hydraulic chamber. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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Specification
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- Resources
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Current AssigneeAisin Seiki Co., Ltd. (Aisin Corp.)
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Original AssigneeAisin Seiki Co., Ltd. (Aisin Corp.)
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InventorsTakahashi, Shigeo, Kondoh, Noriyoshi
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Granted Patent
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Time in Patent OfficeDays
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Field of Search
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US Class Current475/116
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CPC Class CodesF16H 2061/0253 Details of electro hydrauli...F16H 61/0206 Layout of electro-hydraulic...F16H 61/0251 Elements specially adapted ...
