Claims
- 1. An apparatus for stabilizing a vehicle having a supporting frame and an axle suspended from said frame, comprising:
- a plurality of hydraulic cylinders positioned on laterally opposite sides of said vehicle for connecting said supporting frame to said axle;
- a hydraulic supply line extending from said cylinders to a pressurized reservoir of hydraulic fluid;
- a pneumatically actuated pilot-to-open check valve positioned in said supply line to control the flow of hydraulic fluid into and out of said cylinders;
- a first air supply line extending from said pilot-to-open check valve to a first pressurized air supply reservoir;
- a pilot operated shuttle valve located in said first air supply line and being in one of a first valve position which closes said pilot-to-open check valve by venting said shuttle valve to the atmosphere and a second valve position, which opens said pilot-to-open check valve by connecting said pilot-to-open check valve to said pressurized air supply reservoir; and
- means in communication with said first air supply line for pneumatically actuating and deactuating said pilot-to-open check valve while said shuttle valve is in said first valve position, said pneumatic actuation means comprising a second pressurized air supply reservoir connected to a pneumatic valve by a second pneumatic line, said pneumatic valve being in communication with said first air supply line, wherein said pneumatic valve includes a spool which moves between a first spool position that permits a pneumatic signal to be sent to said pilot-to-open check valve to open said check valve and a second spool position that prevents said pneumatic signal from being sent to said check valve.
- 2. The apparatus of claim 1, wherein said pneumatic actuation means further comprises an electrical circuit comprising:
- a first switch for sensing the position of a forward travel control device and a reverse travel control device;
- a second switch that bypasses said first switch; and
- a first solenoid valve electrically connected to said first switch and a second solenoid valve electrically connected to said second switch and further connected to said second pressurized air supply reservoir.
Parent Case Info
This is a division of application Ser. No. 08/124,940, filed Sep. 21, 1993, U.S. Pat. No. 5,388,857, which is a continuation-in-part of application Ser. No. 07/936,129, filed Aug. 27, 1992, abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2852600 |
Jun 1979 |
DEX |
58-183307 |
Oct 1983 |
JPX |
2040839 |
Sep 1980 |
GBX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
124940 |
Sep 1993 |
|
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
936129 |
Aug 1992 |
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