Control system for hydraulic pump system
AssigneeDiesel Equipment Limited
InventorJohn C. Martin
Life of this patent
Estimating the term…
Abstract
Electrically operated hydraulic pump systems are commonly used on tailgate loaders and small dump truck hoists. The systems include a switch which, when closed, couples the vehicle battery to the pump driving motor and a hydraulic lowering valve which, when opened, drains the output port of the pump to a reservoir. The control system for this electric pump system comprises an air cylinder operatively connected to the switch and a second cylinder operatively connected to the hydraulic lowering valve. A switching valve is connected between each air cylinder and a source of air pressure. The switching valves may be operated by an operator to pump or drain hydraulic fluid.
Claims10
Apparatus for controlling hydraulic pump system of the type having hydraulic pump with an output port, a reservoir of hydraulic fluid, a driving means for driving said pump to pump hydraulic fluid from said reservoir to said output port, a switch having an operative position whereat said driving means drives said pump and an inoperative position whereat said driving means does not drive said pump, and hydraulic lowering valve operatively connected to said output port for porting hydraulic fluid from said output port to said reservoir, said control apparatus comprising:
- a first air cylinder having a piston rod adapted for operative coupling to said switch;
- first switchable air valve means adapted for operative connection to said first air cylinder, said first air valve means for connection to a source of air pressure;
- a second air cylinder having a piston rod adapted for operative coupling to said hydraulic lowering valve;
- a second switchable air valve means adapted for operative connection to said second air cylinder, said second air valve means for connection to said source of air pressure, whereby, in use, said first switchable air valve may be switched in order to operate said switch and said second switchable air valve may be switched to operate said hydraulic lowering valve.
An hydraulic pump system comprising:
- an hydraulic pump with an output port;
- a reservoir of hydraulic fluid;
- a driving means for driving said pump to pump hydraulic fluid from said reservoir to said output port;
- a switch having an operative position whereat said driving means drives said pump and an inoperative position whereat said driving means does not drive said pump;
- an hydraulic lowering valve operatively connected to said output port for porting hydraulic fluid from said output port to said reservoir;
- a source for providing air pressure;
- a first air cylinder having a piston rod operatively coupled to said switch;
- first switchable air valve means operatively connected between said first air cylinder and said source for air pressure;
- a second air cylinder having a piston rod operatively coupled to said hydraulic lowering valve;
- a second switchable air valve means operatively connected between said second air cylinder and said source for air pressure, whereby said first switchable air valve may be switched in order to operate said switch and said second switchable air valve may be switched in order to operate said hydraulic lowering valve.
Dependencies are inferred from the claim text.