Hydraulic hammer internal damping

Patent metadata

Field	Value
Publication number	US-12358113-B2
Application number	US-202318162941-A
Country	US
Kind code	B2
Filing date	Feb 1, 2023
Priority date	Feb 1, 2023
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A hydraulic hammer includes: a cylinder having a first cylinder end and a second cylinder end opposite the first cylinder end; a piston disposed within the cylinder, the piston having a first piston end, the piston being reciprocatingly movable with respect to the cylinder along an axial direction; a valve body disposed on the first cylinder end so as to define a valve body cavity; and a seal carrier sealingly arranged between the first piston end and the first cylinder end and being reciprocatingly movable with respect to the cylinder along the axial direction. The piston is reciprocatingly movable with respect to the seal carrier along the axial direction.

First claim

What is claimed is:

1. A hydraulic hammer, comprising:
a cylinder having a first cylinder end and a second cylinder end opposite the first cylinder end;
a piston disposed within the cylinder, the piston having a first piston end, the piston being reciprocatingly movable with respect to the cylinder along an axial direction;
a valve body disposed on the first cylinder end so as to define a valve body cavity; and
a seal carrier sealingly arranged between the first piston end and the first cylinder end and being reciprocatingly movable with respect to the cylinder along the axial direction,
wherein the piston is reciprocatingly movable with respect to the seal carrier along the axial direction,
wherein positioning the seal carrier between the first piston end and the first cylinder end creates a piston receiving space between the first piston end and a damping fluid reservoir within the valve body cavity, and
wherein the seal carrier fluidically separates the damping fluid reservoir from the piston receiving space.

2. The hydraulic hammer of claim 1 , wherein a damping fluid is disposed within the damping fluid reservoir.

3. The hydraulic hammer of claim 2 , wherein, upon a movement of the seal carrier toward the valve body, the damping fluid exerts a damping force on the seal carrier so as to dampen the movement of the seal carrier toward the valve body.

4. The hydraulic hammer of claim 3 , wherein the damping fluid comprises nitrogen.

5. The hydraulic hammer of claim 1 , wherein a magnitude of a movement of the seal carrier toward the valve body is smaller than a magnitude of a movement of the piston toward the first cylinder end.

6. The hydraulic hammer of claim 1 , further comprising:
an accumulator, comprising:
a hydraulic fluid reservoir in fluid communication with the cylinder through at least one fluidic channel in the valve body; and
a pressure reservoir disposed adjacent the hydraulic fluid reservoir.

7. The hydraulic hammer of claim 6 , wherein the accumulator is disposed on the valve body.

8. The hydraulic hammer of claim 6 , wherein the hydraulic fluid reservoir is in fluid communication with a hydraulic circuit of a carrier equipment of the hydraulic hammer.

9. The hydraulic hammer of claim 1 , further comprising:
a front head disposed at the second cylinder end.

10. The hydraulic hammer of claim 9 , further comprising:
a hammer tool disposed at the front head, the hammer tool being reciprocatingly movable with respect to the cylinder in the axial direction,
wherein the piston is axially aligned with the hammer tool such that the piston is configured to impact the hammer tool upon a movement of the piston toward the second cylinder end.

11. The hydraulic hammer of claim 1 , further comprising:
a hydraulic coupling in fluid communication with a hydraulic circuit of a carrier equipment of the hydraulic hammer.

12. The hydraulic hammer of claim 11 , wherein the valve body comprises at least one fluidic channel in fluid communication with the hydraulic coupling.

13. A damping system for a hydraulic hammer, comprising:
a cylinder;
a piston movably disposed within the cylinder;
a seal carrier arranged between a first end of the cylinder and a first end of the piston, the seal carrier providing a sealing of the piston with respect to the cylinder, the seal carrier being movable with respect to the cylinder along an axial direction of the damping system; and
a valve body disposed on the first end of the cylinder,
wherein the piston is movably disposed with respect to the seal carrier along the axial direction,
wherein the valve body defines a valve body cavity,
wherein positioning the seal carrier between the first piston end and the first cylinder end creates a piston receiving space between the first piston end and a damping fluid reservoir within the valve body cavity, and
wherein the seal carrier fluidically separates the damping fluid reservoir from the piston receiving space.

14. The damping system of claim 13 , wherein a movement of the piston toward the first end of the cylinder is configured to cause a movement of the seal carrier toward the valve body.

15. The damping system of claim 14 , wherein the movement of the seal carrier toward the valve body is configured to compress the damping fluid reservoir so as to dampen the movement of the seal carrier toward the valve body.

16. The damping system of claim 14 , wherein a magnitude of the movement of the seal carrier toward the valve body is smaller than a magnitude of the movement of the piston toward the first end of the cylinder.

17. The damping system of claim 13 , further comprising:
a hydraulic coupling in fluid communication with a hydraulic circuit of a carrier equipment of the hydraulic hammer.

18. The damping system of claim 17 , wherein the valve body comprises at least one fluidic channel in fluid communication with the hydraulic coupling.

Assignees

• Caterpillar Inc

Inventors

• Moore Cody T
• Clemons John K

Classifications

• B25D2209/002

  Pressure accumulators · CPC title

• B25D17/06

  Hammer pistons; Anvils {; Guide-sleeves for pistons} · CPC title

• B25D9/12 Primary

  comprising a built-in liquid motor {, i.e. the tool being driven by hydraulic pressure} · CPC title

• B25D2217/0073

  Arrangements for damping of the reaction force · CPC title

• B25D17/245 Primary

  using a fluid · CPC title