Resources Contact Us Home
Hydraulic unloading valves

Image Number 3 for United States Patent #4766926.

An hydraulic unloading valve for unloading hydraulic fluid from a circuit pressurized by a diesel engine powered pump under cold climate conditions to assist starting of the engine. The valve has an inlet through which fluid enters the valve, an outlet through which fluid may leave the valve, an outlet valve seat, a valve member movable towards and away from the valve seat and carrying a valve surface for closing off the seat valve, a first orifice sensitive to viscosity which in response to the flow of fluid through the inlet generates a first pressure drop arranged to tend to move the valve member away from the valve seat, and second orifice which is not sensitive to viscosity and which in response to said flow generates a second pressure drop arranged to tend to move the valve towards the valve seat to bring the valve seat and surface into contact to close-off through the valve outlet when the second pressure drop is greater than the first pressure drop. The pressure drop characteristics of the two orifices can be arranged so that at lower fluid temperatures of say below -10 degrees C. the valve is held open up to higher fluid flow rates, thus relieving load on the engine and assisting cold starting.

  Recently Added Patents
Field device for determining or monitoring a physical or chemical process variable
Semiconductor device and manufacturing method thereof
Apparatus and method for transmitting/receiving data in a communication system
Shoe bag
Document layout method
Normalized contextual performance metric for the assessment of fatigue-related incidents
Transcription factor
  Randomly Featured Patents
Pseudo-plastic or thixotropic liquid deodorant product for ostomy pouches
Antisense oligonucleotides for mitogen-activated protein kinases as therapy for cancer
Sports glove
Method of treating metabolic bone diseases with 18-nor-vitamin D compounds
Joint between a metal part and a ceramic part based SiC and/or C
LCD with TFT on upper substrate and color filter on each substrate
Control apparatus for dryer
Oil filter and dehydrator
Spraying device
Continuous transmission mode radio with control information monitoring capability