Resources Contact Us Home
Solenoid self-cleaning pressure valve for automatic vehicle transmission

Image Number 4 for United States Patent #5971889.

A system for controlling an automatic vehicle transmission, including a gear system and hydraulic clutches which hold a member of the gear system stationary to produce gear reduction or reverse, having an oil line which connects the clutches to an oil pressure source, a pressure control valve having a solenoid provided in the oil line which generates a regulated oil pressure to be supplied to the clutches in response to a current supplied to the solenoid, a switch valve provided in the oil line which switches the oil pressure to be supplied to the one of the clutches between the regulated oil pressure and a line pressure. In the system, it is discriminated whether the pressure control valve does not supply the regulated oil pressure to the clutches and if so, a dither current is supplied to the solenoid such that the valve repeatedly performs a vibrational motion to remove any grit therefrom, thereby removing grit without causing gear-shift shock or clutch vibration.

  Recently Added Patents
Cooling method and device for cooling a medium-voltage electrical installation in a protective sheath
Methods and system for providing drug pricing information from multiple pharmacy benefit managers (PBMs)
Adaptive switch mode LED system
Discharge lamp lighting circuit
LED package with top and bottom electrodes
Interactivity model for shared feedback on mobile devices
Light-emitting device package structure
  Randomly Featured Patents
Apparatus and method using compressed codes for scheduling broadcast information recording
Method and system for handling two CA systems in a same receiver
Flameless heat source
Hydraulic drive system with temperature compensation for pressure limit
Method and apparatus for motion estimation
Air winch control valve
Vehicle door structure
Wired board with improved bonding pads