Fluid delivery system

Patent metadata

Field	Value
Publication number	US-10981554-B2
Application number	US-201815985920-A
Country	US
Kind code	B2
Filing date	May 22, 2018
Priority date	Jun 7, 2017
Publication date	Apr 20, 2021
Grant date	Apr 20, 2021

Abstract

A system for delivering fluid in a machine is provided. The system includes a pump, a first valve disposed downstream of the pump, a check valve disposed downstream of the first valve, at least one accumulator disposed downstream of the check valve, and an auxiliary system disposed upstream of the check valve. The system further includes a control unit configured to receive a signal indicative of a fluid demand from the auxiliary system. The control unit is also configured to selectively control the first valve in a first position to limit flow of the fluid from the pump to the auxiliary system, and in a second position to allow flow of the fluid from the pump to the auxiliary system based, at least in part, on the received signal. The check valve limits flow of a fluid from the at least one accumulator to the auxiliary system.

First claim

What is claimed is:

1. A system for delivering a fluid in a machine, the system comprising:
a main line;
a pump configured to provide a flow of the fluid via the main line;
a first valve in fluid communication with the flow of fluid provided by the pump via a first fluid connection disposed in the main line downstream of the pump, wherein the first valve is configured to move between a first position and a second position;
a check valve in fluid communication with the pump and disposed downstream of the first fluid connection to the first valve;
at least one accumulator disposed downstream of the check valve to receive fluid from the pump via the main line, wherein the at least one accumulator is associated with a brake of the machine;
an auxiliary system for receiving the flow of fluid from the pump via a second fluid connection disposed in the main line upstream of the check valve, wherein the auxiliary system comprises a traction control system employing a hydraulically operated cross axle differential; and
a control unit communicably coupled to the first valve and the auxiliary system, and configured to:
receive a signal indicative of a fluid demand from the auxiliary system; and
control the first valve, selectively, in the first position to limit the flow of the fluid from the pump to the auxiliary system, and in the second position to allow the flow of the fluid from the pump to the auxiliary system based on the received signal, wherein the check valve limits a flow of a fluid from the at least one accumulator to the auxiliary system;

a third valve arranged between the second fluid connection and the auxiliary system and communicably coupled to the control unit, wherein:
a working pressure of the auxiliary system is lower than a working pressure of the at least one accumulator; and
the third valve is configured to move in a first position to limit the flow of the fluid from the pump to the auxiliary system, and in a second position to allow the flow of fluid from the pump to the auxiliary system based on the received auxiliary fluid demand signal indicative of the fluid demand from the auxiliary system,
an orifice disposed in the main line downstream of the second fluid connection to the auxiliary system and upstream of the check valve and the first fluid connection to the first valve; and
a pressure sensor in fluid communication with the at least one accumulator and communicably coupled to the control unit, and configured to generate an accumulator pressure signal indicative of a pressure of the fluid in the at least one accumulator, wherein the control unit is further configured to:
receive the signal indicative of the pressure from the pressure sensor; and control the first valve, selectively, in the first position to limit the flow of the fluid from the pump to the at least one accumulator, and in the second position to allow the flow of fluid from the pump to the at least one accumulator based on the received accumulator pressure signal.

2. The system of claim 1 , wherein the control unit further includes a first controller communicably coupled to the auxiliary system, and configured to:
receive the signal indicative of the fluid demand from the auxiliary system; and
generate a signal indicative of controlling the first valve.

3. The system of claim 2 , wherein the control unit further includes a second controller communicably coupled to the first valve and the first controller, and configured to:
receive the signal indicative of controlling the first valve from the first controller; and
control the first valve, selectively, in the first position to limit the flow of the fluid from the pump to the auxiliary system, and in the second position to allow the flow of the fluid from the pump to the auxiliary system based, at least in part, on the received signal, wherein the check valve limits the flow of the fluid from the at least one accumulator to the auxiliary system.

4. The system of claim 3 , wherein the second controller is further communicably coupled to the pressure sensor, and configured to:
receive the signal indicative of the pressure from the pressure sensor; and
control the first valve, selectively, in the first position to limit the flow of the fluid from the pump to the at least one accumulator, and in the second position to allow the flow of the fluid from the pump to the at least one accumulator based on the received signal.

5. The system of claim 3 , further including a second valve in fluid communication with the pump and the at least one accumulator, and disposed downstream of the check valve.

6. The system of claim 5 , wherein the pressure sensor is disposed downstream of the check valve and upstream of the second valve.

7. The system of claim 5 , wherein the at least one accumulator includes a plurality of accumulators fluidly coupled to the second valve.

8. The system of claim 5 , wherein the second valve is an inverse shuttle valve.

9. The system of claim 3 , wherein the third valve is communicably coupled to the second controller.

10. The system of claim 1 , wherein the first valve is disposed downstream of the auxiliary system.

11. The system of claim 1 , wherein the first valve is a solenoid actuated valve.

12. A method for providing a flow of a fluid in a machine, the machine including a pump, a first valve, a second valve, a third valve, a check valve, an auxiliary system comprising a traction control system employing a hydraulically operated cross axle differential, at least one accumulator associated with a brake of the machine, and a pressure sensor, the method comprising:
receiving an auxiliary fluid demand signal indicative of a fluid demand from the traction control system;
controlling the first valve, selectively, in a first position to limit the flow of the fluid from the pump to the auxiliary system, and in a second position to allow the flow of the fluid from the pump to the traction control system based on the received auxiliary fluid demand signal, wherein the check valve limits a flow of the fluid from the at least one accumulator to the auxiliary system;
selecting a working pressure of the traction control system to be lower than a working pressure of the at least one accumulator;
receiving an accumulator pressure signal indicative of a pressure in the at least one accumulator from the pressure sensor;
controlling the first valve, selectively, in the first position to limit the flow of the fluid from the pump to the at least one accumulator, and in the second position to allow the flow of the fluid from the pump to the at least one accumulator based on the received accumulator pressure signal; and
controlling the third valve in a first position to limit the flow of the fluid from the pump to the auxiliary system, and in a second position to allow the flow of the fluid from the pump to the auxiliary system based on the received auxiliary fluid demand signal indicative of the fluid demand from the auxiliary system.

Assignees

• Caterpillar Sarl

Inventors

• Adeeb Adam J
• Johnson Steven Edward
• Weltzer Anthony Joseph
• Stoops Ernest Everett

Classifications

• F15B1/027

  having accumulator charging devices · CPC title

• F04B7/0073

  the member being of the lost-motion type, e.g. friction-actuated members, or having means for pushing it against or pulling it from its seat · CPC title

• B60T13/16

  using pumps directly, i.e. without interposition of accumulators or reservoirs · CPC title

• F04B49/035

  Bypassing · CPC title

• B60T13/148

  Arrangements for pressure supply · CPC title