System and method for preventing air in lubricant supply lines

Patent metadata

Field	Value
Publication number	US-10480712-B2
Application number	US-201715701597-A
Country	US
Kind code	B2
Filing date	Sep 12, 2017
Priority date	Nov 15, 2016
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

A lubrication system for a hydraulically operated tool has a common lubricant supply manifold that receives a lubricant from one or more lubricant reservoirs. The common lubricant supply manifold includes an inlet port through which the lubricant is received and an exit port fluidly coupled with a lubricant supply line. The system also has a primer pump connected in fluid communication with the common lubricant supply manifold, a main lubricant supply pump, and a spring check valve downstream of the main lubricant supply pump. The lubricant supply line receives lubricant from the exit port and supplies the lubricant to the main lubricant supply pump. The main lubricant supply pump increases the pressure of the lubricant and pumps the lubricant through the spring check valve and into a fluid passageway leading to the hydraulically operated tool. A detune valve is in fluid communication with a hydraulic pump providing pressurized hydraulic fluid for the tool and the main lubricant supply pump, and the detune valve is actuated by pressure in the lubricant supply line.

First claim

What is claimed is:

1. A lubrication system for a hydraulically operated tool, the system comprising:
a common lubricant supply manifold configured to receive a lubricant from one or more lubricant reservoirs, the common lubricant supply manifold including at least one inlet port through which the lubricant is received and at least one exit port fluidly coupled with a lubricant supply line;
a primer pump connected in fluid communication with the common lubricant supply manifold;
a main lubricant supply pump;
a spring check valve downstream of the main lubricant supply pump;
the lubricant supply line being configured to receive lubricant from the at least one exit port and supply the lubricant to the main lubricant supply pump;
the main lubricant supply pump being configured to increase the pressure of the lubricant and pump the lubricant through the spring check valve and into a fluid passageway leading to the hydraulically operated tool; and
a detune valve in fluid communication with a hydraulic pump providing pressurized hydraulic fluid for the tool and the main lubricant supply pump, the detune valve configured to be actuated by pressure in the lubricant supply line.

2. The lubrication system of claim 1 , wherein:
the one or more lubricant reservoirs include two replaceable lubricant cartridges connected to the lubricant supply manifold at two spaced inlet ports; and
two exit ports in the lubricant supply manifold in between the two spaced inlet ports are each fluidly coupled with the lubricant supply line through a one-way check valve configured to prevent lubricant from flowing back through the exit port into the lubricant supply manifold.

3. The lubrication system of claim 2 , further including two primer pumps, wherein a first one of the two primer pumps is fluidly coupled to a first end of the lubricant supply manifold upstream from a first one of the two spaced inlet ports, and a second one of the two primer pumps is fluidly coupled to a second, opposite end of the lubricant supply manifold upstream from a second one of the two spaced inlet ports.

4. The lubrication system of claim 3 , wherein the two primer pumps and the main lubricant supply pump are piston pumps.

5. The lubrication system of claim 1 , wherein the primer pump is configured to produce a lubricant pressure in the lubricant supply manifold and in the lubricant supply line that is greater than a first threshold pressure and less than a second threshold pressure sufficient to open the spring check valve downstream of the main lubricant supply pump.

6. The lubrication system of claim 5 , wherein the detune valve is configured to be actuated to a first position against a biasing force by a lubricant pressure in the lubricant supply line that is greater than or equal to the first threshold pressure, and direct pressurized hydraulic fluid from the hydraulic pump to the main lubricant supply pump when the detune valve is in the first position.

7. The lubrication system of claim 6 , wherein the detune valve is configured to be actuated to a second position by the biasing force when the lubricant pressure in the lubricant supply line is less than the first threshold pressure, and bypass the pressurized hydraulic fluid from the hydraulic pump such that the pressurized hydraulic fluid is not supplied to the main lubricant supply pump when the detune valve is in the second position.

8. The lubrication system of claim 1 , wherein the primer pump and the main lubricant supply pump are each piston pumps operated by pressurized hydraulic fluid from the hydraulic pump.

9. The lubrication system of claim 8 , wherein a pressure of pressurized hydraulic fluid supplied from the hydraulic pump to the primer pump and to the main lubricant supply pump results in the primer pump displacing a greater volume of lubricant than displaced by the main lubricant supply pump, and the main lubricant supply pump producing a greater pressure of lubricant than produced by the primer pump.

10. A method of lubricating a hydraulically operated tool and preventing the introduction of air into lubricant supply lines, the method comprising:
receiving a lubricant at one or more inlets of a common lubricant supply manifold;
increasing the pressure of the lubricant in the common lubricant supply manifold with a primer pump to a pressure that is greater than a first threshold pressure and less than a second threshold pressure;
supplying the pressurized lubricant from the common lubricant supply manifold through one or more exit ports to a lubricant supply line;
sensing the pressure of the lubricant in the lubricant supply line at a detune valve, the detune valve being in fluid communication with a hydraulic pump providing pressurized hydraulic fluid for operating the tool, and for operating a main lubricant supply pump configured to receive lubricant from the lubricant supply line;
receiving the lubricant in the lubricant supply line at the main lubricant supply pump; and
increasing the pressure of the lubricant with the main lubricant supply pump to a pressure that is greater than the second threshold pressure, and sufficient to pump the lubricant through a spring check valve and into a fluid passageway leading to the hydraulically operated tool, wherein the detune valve is actuated by the pressure of the lubricant in the lubricant supply line dropping below the first threshold to bypass the pressurized hydraulic fluid from being supplied to the main lubricant supply pump and stop operation of the main lubricant supply pump.

11. The method of claim 10 , wherein:
lubricant is received at two spaced inlet ports of the common lubricant supply manifold from two replaceable lubricant cartridges; and
lubricant is supplied from the common lubricant supply manifold through two exit ports in the lubricant supply manifold that are positioned in between the two spaced inlet ports and into the lubricant supply line through one-way check valves configured to prevent lubricant from flowing back through the exit ports into the lubricant supply manifold.

12. The method of claim 11 , further including fluidly coupling a first primer pump to a first end of the common lubricant supply manifold upstream from a first one of the two spaced inlet ports, and fluid coupling a second primer pump to a second, opposite end of the common lubricant supply manifold upstream from a second one of the two spaced inlet ports.

13. The method of claim 10 , further including:
actuating the detune valve to a first position against a biasing force when a lubricant pressure in the lubricant supply line is greater than or equal to the first threshold pressure; and
directing pressurized hydraulic fluid from the hydraulic pump to the main lubricant supply pump when the detune valve is in the first position.

14. The method of claim 13 , further including:
actuating the detune valve to a second position by the biasing force when the lubricant pressure in the lubricant supply line is less than the first threshold pressure; and
bypassing the pressurized hydraulic fluid from the hydraulic pump such that the pressurized hydraulic fluid is not supplied to the main lubricant supply pump when the detune valve is in the second position.

15. The method of claim 10 , wherein the primer pump and the main lubricant supply pump are each piston pumps operated by pressurized hydraulic fluid from the hydraulic pump.

16. The method of claim 15 , wherein a pressure of pressurized hydraulic fluid supplied from the hydraulic pump to the primer pump and to the main lubricant supply pump results in the primer pump di

Assignees

• Caterpillar Inc

Inventors

• Moore Cody T

Classifications

• F16N7/36

  with feed by pumping action of the member to be lubricated or of a shaft of the machine; Centrifugal lubrication · CPC title

• F16N7/38

  with a separate pump; Central lubrication systems · CPC title

• F16N39/002

  by deaeration (degasification of liquids B01D19/00) · CPC title

• B23Q11/10

  Arrangements for cooling or lubricating tools or work · CPC title

• F16N13/16 Primary

  with fluid drive · CPC title