发明名称 |
Method of controlling clutch-to-clutch shifts for a powershift transmission |
摘要 |
In one aspect of the present invention, an electronic shift control for a powershift transmission is disclosed. The transmission includes a plurality of speed and direction changing clutches. A plurality of pressure control valves are individually connected to the clutches. A hydraulic pump delivers pressurized hydraulic oil to predetermined pressure control valves to meter hydraulic fluid in response to receiving a clutch command signal. The method produces a shift from a first transmission ratio to a second transmission ratio through disengagement of an off-going clutch associated with the first transmission ratio and engagement of an on-coming clutch associated the second transmission ratio. The method includes filing an on-coming speed clutch, releasing an off-going direction clutch in response to the on-coming speed clutch being filled, and thereafter, gradually increasing the on-coming speed clutch pressure to engage the speed clutch. Finally, the on-coming direction clutch pressure is gradually increased to engage the direction clutch in response to the on-coming speed clutch being engaged.
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申请公布号 |
US5467854(A) |
申请公布日期 |
1995.11.21 |
申请号 |
US19940257391 |
申请日期 |
1994.06.07 |
申请人 |
CATERPILLAR INC. |
发明人 |
CREGER, TODD D.;MITCHELL, RANDALL M.;STAHL, ALAN L.;TALBOTT, JAMES R. |
分类号 |
F16H61/08;F16H59/36;F16H59/46;F16H59/72;F16H61/02;F16H61/06;(IPC1-7):F16D25/10;F16D48/06 |
主分类号 |
F16H61/08 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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