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U.S. Department of Energy
Office of Scientific and Technical Information

Automatic transmission with upshift smoothing valve

Patent ·
OSTI ID:5896956

This patent describes a transmission control in an automatic transmission comprising the mechanical transmission mechanism comprising a lower side hydraulic fluid pressure actuated friction engagement device and a higher side hydraulic fluid pressure actuated friction engagement device. The lower side friction engagement device is engaged and the higher side friction engagement device is disengaged when a certain lower speed stage of the transmission is engaged, and the lower side friction engagement device is disengaged and the higher side friction engagement device is engaged when a certain higher speed stage one higher than the lower speed stage of the transmission is engaged. The transmission control device, comprises: (a) a two position valve means for selectively supplying actuating fluid pressure either to the lower side friction engagement device and draining the higher side friction engagement device to provide the lower speed stage, or for draining the lower side friction engagement device through a certain drain path and supplying actuating fluid pressure to the higher side friction engagement device to provide the higher speed stage; (b) the certain drain path extending from the lower side friction engagement device to and through the two position valve means; (c) output means for supplying a throttle pressure corresponding to the power output of an engine to which the transmission is connected; (d) a variable flow resistance control valve means interposed in the certain drain path between the two position valve means and the lower side friction engagement device and connected to the output means; and (e) a one-way valve and an orifice bypass provided in parallel with each other and with the variable flow resistance control valve means.

Assignee:
Honda Giken Kogyo Kabushiki Kaisha, Tokyo
Patent Number(s):
US 4706523
OSTI ID:
5896956
Country of Publication:
United States
Language:
English