Power tool hydraulic system

Patent metadata

Field	Value
Publication number	US-12370611-B2
Application number	US-202318211440-A
Country	US
Kind code	B2
Filing date	Jun 19, 2023
Priority date	Jun 17, 2022
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

The present disclosure provides a power tool including a housing and a hydraulic drive assembly at least partially supported in the housing. The housing includes a handle that supports a switch that activates the tool. The hydraulic drive assembly includes a pump assembly operably coupled to the motor assembly, a reservoir configured to contain hydraulic fluid in fluid communication with the pump assembly and in which a baffle is supported, a cylinder in fluid communication with the pump assembly which supports an auto-return valve therein, and a piston disposed in the cylinder and biased to a first position by a piston spring. The pump assembly includes a manifold housing that at least partially defines an inlet passageway that fluidly communicates the pump assembly and the cylinder and supports an inlet check valve.

First claim

What is claimed is:

1. A hydraulic tool comprising:
a housing including a handle, the handle supporting a switch configured to activate the hydraulic tool; and
a hydraulic drive assembly at least partially supported in the housing and activated by the switch, the hydraulic drive assembly including
a motor assembly,
a pump assembly operably coupled to the motor assembly, the pump assembly including a manifold housing in which an inlet passageway is at least partially defined,
a reservoir configured to contain hydraulic fluid, the reservoir in fluid communication with the pump assembly,
a baffle supported within the reservoir,
a cylinder in fluid communication with the pump assembly, the cylinder supporting an auto-return valve,
a piston disposed in the cylinder and slidable relative thereto from a first position, the piston configured to be coupled to a tool output, and
a piston spring disposed in the cylinder, the piston spring engaging the piston and biasing the piston toward the first position,
wherein the inlet passageway fluidly communicates the pump assembly and the cylinder, the inlet passageway supporting an inlet check valve, and
wherein a direction of motor assembly operation is reversed to reduce hydraulic pressure in the inlet passageway.

2. The hydraulic tool of claim 1 , wherein the auto-return valve includes a spring, the spring biasing the auto-return valve to an open position.

3. The hydraulic tool of claim 2 , wherein the auto-return valve defines a first side in fluid communication with the inlet passageway, the auto-return valve configured to experience a hydraulic force opposing the bias of the spring.

4. The hydraulic tool of claim 3 , wherein the hydraulic force required to open the inlet check valve is higher than the hydraulic force in the inlet passageway required to overcome the bias of the spring.

5. The hydraulic tool of claim 4 , wherein the auto-return valve opens in response to a reduction below an opening threshold of hydraulic pressure in the inlet passageway.

6. The hydraulic tool of claim 1 , further comprising a wiper seal positioned circumferentially about the piston, the wiper seal engaging the piston.

7. The hydraulic tool of claim 1 , further comprising a manual release assembly mechanically engaging a manual release valve, the manual release assembly including
a manual release button coupled to the housing and engageable by a user,
a first lever selectively engageable by the manual release button, and
a second lever engageable by the first lever, the second lever engageable with the manual release valve.

8. The hydraulic tool of claim 1 , wherein the hydraulic tool is one of a crimping tool and a cutting tool.

9. The hydraulic tool of claim 1 , further comprising:
a pressure sensor at least partially disposed in the inlet passageway and configured to measure a hydraulic pressure of hydraulic fluid in the inlet passageway; and
a tool controller configured to monitor the hydraulic pressure and increment a counter upon the hydraulic pressure exceeding an operation threshold, the tool controller disabling operation of the hydraulic tool upon the counter exceeding a threshold.

10. The hydraulic tool of claim 9 , wherein the tool controller is configured to selectively initiate an indicator operation in response to the counter exceeding a predefined value less than the threshold.

11. The hydraulic tool of claim 1 , wherein the motor assembly is operable to drive the pump assembly and pressurize the cylinder, thereby moving the piston from the first position, in response to actuation of the switch, and wherein the hydraulic drive assembly is configured to return the piston to the first position in response to the switch being released.

12. A hydraulic tool comprising:
a housing including a handle, the handle supporting a switch configured to activate the hydraulic tool; and
a hydraulic drive assembly at least partially supported in the housing and activated by the switch, the hydraulic drive assembly including
a motor assembly,
a pump assembly operably coupled to the motor assembly, the pump assembly including a manifold housing in which an inlet passageway is at least partially defined,
a reservoir configured to contain hydraulic fluid, the reservoir in fluid communication with the pump assembly,
a baffle supported within the reservoir,
a cylinder in fluid communication with the pump assembly, the cylinder supporting an auto-return valve,
a piston disposed in the cylinder and slidable relative thereto from a first position, the piston configured to be coupled to a tool output, and
a piston spring disposed in the cylinder, the piston spring engaging the piston and biasing the piston toward the first position,

wherein the inlet passageway fluidly communicates the pump assembly and the cylinder, the inlet passageway supporting an inlet check valve, and
wherein the cylinder is in fluid communication with the reservoir via an outlet passageway, the outlet passageway having an outlet directed toward the baffle.

13. The hydraulic tool of claim 12 , wherein the baffle includes a plate portion disposed adjacent to and facing the outlet of the outlet passageway such that the baffle is configured to diffuse a flow of hydraulic fluid through the outlet such that the flow of hydraulic fluid through the outlet does not directly impinge upon a side of the reservoir.

14. The hydraulic tool of claim 13 , wherein the baffle is made of stainless steel.

15. A hydraulic drive assembly of a power tool comprising:
a switch;
a motor assembly operable to provide a rotational output;
a gear assembly configured to receive the rotational output from the motor assembly;
a pump assembly operably coupled to the gear assembly, the pump assembly configured to generate a flow of hydraulic fluid;
a reservoir in fluid communication with the pump assembly and configured to store hydraulic fluid;
a baffle supported in the reservoir; and
a cylinder in which a piston is slidably supported, the piston slidable from a first position in response to actuation of the switch and operation of the motor assembly to drive the pump assembly and pressurize the cylinder, the cylinder in fluid communication with the reservoir via an inlet passageway and an outlet passageway, the outlet passageway having an outlet directed toward the baffle,
wherein the piston returns to the first position in response to the switch being released.

16. The hydraulic drive assembly of claim 15 , further comprising a manual release valve positioned in the inlet passageway and operable to return the piston toward the first position.

17. The hydraulic drive assembly of claim 16 , further comprising a manual release assembly including a first lever, a manual release button engageable with the first lever, and a second lever engageable with the first lever and with the manual release valve to operate the manual release valve.

18. The hydraulic drive assembly of claim 15 , further comprising an auto-return valve positioned in the outlet passageway between the cylinder and the reservoir, the auto-return valve having a first side in fluid communication with the inlet passageway and a second side, the second side in fluid communication with the outlet passageway.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Rentmeester Mathew R
• Reeve John N
• Garces Daniel R
• Mach Brennan L
• Frey Adam C
• Hyde Brian J
• Snyder Harrison T

Classifications

• B25F5/02

  Construction of casings, bodies or handles {(B25F5/006, B25F5/008 take precedence)} · CPC title

• B25F5/005 Primary

  Hydraulic driving means · CPC title

• B23D29/005

  for cutting sheets · CPC title

• B23D29/02

  Hand-operated metal-shearing devices · CPC title

• B23D23/00

  Machines or devices for shearing or cutting profiled stock (hand-held devices B23D29/00) · CPC title