Hydraulic pump

Patent metadata

Field	Value
Publication number	US-12311519-B2
Application number	US-202418637113-A
Country	US
Kind code	B2
Filing date	Apr 16, 2024
Priority date	Sep 7, 2018
Publication date	May 27, 2025
Grant date	May 27, 2025

Abstract

A hydraulic pump includes a work port configured to supply fluid to a hydraulic tool. A high-flow piston supplies fluid along a first flow path to the work port and plurality of high-pressure pistons supplies fluid along a second flow path to the work port. An unloading valve is positioned along the first flow path and actuates from an open state to a closed state when a pressure level of the fluid in the second flow path exceeds a first threshold pressure. A controller allows a user to select a mode of operation. The controller sets a second threshold pressure of the hydraulic pump based on the selected mode of operation, and the second threshold pressure corresponds to an end operation of the hydraulic tool.

First claim

The invention claimed is:

1. A hydraulic pump to provide fluid to a hydraulic tool to perform an operation on a workpiece, the hydraulic pump comprising:
a work port that supplies fluid to the hydraulic tool;
a high-flow piston that supplies fluid along a first flow path to the work port;
a plurality of high-pressure pistons that supply fluid along a second flow path to the work port;
an unloading valve positioned along the first flow path, the unloading valve actuating from an open state to a closed state when a pressure level of fluid in the second flow path exceeds a first threshold pressure; and
a controller to allow a user to select a mode of operation, the controller setting a second threshold pressure of the hydraulic pump based on the mode of operation, the second threshold pressure corresponding to an end operation of the hydraulic tool.

2. The hydraulic pump of claim 1 , wherein the unloading valve permits fluid to flow from the high-flow piston to the work port in the open state and inhibits fluid from flowing from the high-flow piston to the work port in the closed state.

3. The hydraulic pump of claim 1 , and further comprising:
an electric motor; and
a mechanical transducer coupled between the electric motor and the high-flow piston and the plurality of high-pressure pistons, the mechanical transducer including a cam to convert rotational motion of the electric motor into linear movement of the high-flow piston and the plurality of high-pressure pistons.

4. The hydraulic pump of claim 1 , wherein the controller is a first remote controller and the hydraulic pump:
detects a loss of wireless communication with the first remote controller; and
wirelessly communicates with a second remote controller to authenticate the second remote controller and pair with the second remote controller.

5. The hydraulic pump claim 4 , wherein the first remote controller wirelessly communicates at a frequency less than approximately 1 gigahertz (GHz).

6. The hydraulic pump of claim 1 , wherein the unloading valve includes:
a first chamber fluidly coupled to the first flow path;
a second chamber fluidly coupled to the second flow path; and
a plunger movably disposed in the second chamber to selectively couple the first chamber to a tank.

7. The hydraulic pump of claim 6 , wherein the second chamber is fluidly coupled to the tank and a ball is disposed within the first chamber to selectively couple the first chamber to the second chamber, the plunger moving the ball from a seated position that blocks the first chamber from the second chamber to an unseated position that couples the first chamber to the second chamber, the ball being biased toward the seated position by a spring.

8. The hydraulic pump of claim 1 , and further comprising a dump valve with a movable element that moves between a first position to a second position based on a pressure differential between the second flow path and the work port, the movable element blocking the work port from a tank in the first position and the movable element coupling the work port to the tank in the second position.

9. The hydraulic pump of claim 8 , wherein pressure from the second flow path acts on a first surface of a moveable element and pressure from the work port acts on a second surface of the moveable element, the movable element moving from the first position to the second position when the pressure differential is greater than a threshold pressure differential.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Ballard James G
• Radtke Timothy
• Garces Daniel
• Zimmerman Ian C

Classifications

• F04B2205/16

  Opening or closing of a valve in a circuit · CPC title

• F04B2201/06

  Valve parameters · CPC title

• F04B49/22

  by means of valves (F04B49/03 takes precedence) · CPC title

• F04B49/08

  Regulating by delivery pressure · CPC title

• F04B49/06

  Control using electricity (regulating by means of floats actuating electric switches F04B49/04) · CPC title