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
Cosmetic composition based on a supramolecular polymer and a hyperbranched functional polymer
Apparatus for controllable delay cell and associated methods
Method and system to generate finite state grammars using sample phrases
Playback device, playback method, and computer program
Pausing a VoiceXML dialog of a multimodal application
Method and apparatus for controlled reoxygenation
Image forming apparatus, control method and computer-readable medium for stopping a print job during printing by a printer
  Randomly Featured Patents
Carpet cleaning apparatus with auxiliary cleaning device arrangement
Flexural mechanism for passive angle alignment and locking
Grafting of a polymer onto cellophane by ultrasonic induced free radical polymerization
Fixing belt, fixing unit and image forming apparatus
Filtered resuscitation mouthpiece assembly with separable operator and patient mouthpiece structures
Benzoxazole derivatives
Dispensing container for carbonated beverages
Ladders for transoms of boats
Cassette film type indicator for a still camera
Cell-phone operation giving increased full service in manual/select mode