Tool for hydraulic hammer

Abstract

A tool for working a hydraulic hammer (406) of a machine (100) is disclosed herein. The tool includes a spline section (302) and a tool section (304). The spline section (302) includes a first spline section (306) including at least six spline grooves (312) and a second spline section (308) including at least six spline grooves (312). The first spline section (306) and the second spline section (308) are separated by a spacer (310). The tool section diameter (316) is 3.2-4.8 times the spline groove diameter, and the tool section diameter (316) is smaller than the spline section (302) diameter.

Description

Technical Field

[0001] The present disclosure relates generally to a hammer assembly for a work machine, and more particularly to a hammer tool of the hammer assembly. Background Art

[0002] Work machines such as excavators, backhoes, skid steer loaders, wheel loaders, tractors, etc. are provided with hammer assembly tools to break rock, concrete, earth, etc. Such hammer tools can be hydraulically powered using a hydraulic circuit supplied with fluid to operate the hammer assembly. Generally, a hydraulic hammer includes a piston that provides a reciprocating motion to the tool to break rock, earth, concrete, or other materials. The reciprocating piston can be driven by high-pressure fluid from the hydraulic system. The force of the reciprocating piston can be transmitted to the material to be broken via the work tool.

[0003] Current hammer assemblies generally use a cylindrical bushing into which the work tool is inserted when received in the hammer housing of the hammer assembly. However, the cylindrical bushing has certain disadvantages because the cylindrical bushing is usually machined from solid stock, resulting in material waste. Therefore, when the work tool contacts the bushing, this usually results in high contact pressure and accelerated wear. In addition, the bushing is usually very large and heavy, which makes replacement and maintenance more difficult. Since the tool is part of the hydraulic hammer assembly, the impact force of the hydraulic hammer is transmitted to the material through the part, so the tool and bushing may experience significant wear. Therefore, it may be necessary for the tool to be replaced at the work site. It is also necessary for the tool to perform efficiently by reducing the stress imposed on the work tool while reducing the frequency of replacing component parts.

[0004] Other disclosures have disclosed tools for hydraulic hammer assemblies, but have failed to provide tools that can be easily replaced and more uniformly handle stress from the piston to achieve a longer service life. For example, U.S. Publication No. 2017136611 discloses a tool configured to be coupled to a hydraulic hammer. The tool includes an upper portion and a lower portion connected to the upper portion, the upper portion including a shaft having a plurality of upper grooves, a plurality of lower grooves, and a circumferential recess disposed between the plurality of upper grooves and the plurality of lower grooves, and the lower portion includes a tool tip. The present disclosure fails to disclose a tool that can handle more uniform stress levels and reduce asymmetric bending from the operation of a work machine hammer assembly.

[0005] It can therefore be seen that a need exists for an improved work tool for a hydraulic hammer of a work machine that improves efficiency, operability and versatility during installation, operation and maintenance of the work machine. Summary of the invention

[0006] According to one aspect of the present disclosure, a tool for a hydraulic hammer of a working machine is disclosed, wherein the tool comprises a spline section and a tool section, wherein the spline section comprises a first spline partition and a second spline partition, wherein the first spline partition comprises at least six spline grooves, the second spline partition comprises at least six spline grooves, the first spline partition and the second spline partition are separated by a spacer, and the diameter of the tool section is smaller than the diameter of the spline section.

[0007] According to another aspect of the present disclosure, a hammer assembly is disclosed herein. The hammer assembly includes a hammer case and a hammer tool. The hammer case includes a hammer and a working chamber, the working chamber having a plurality of splines, a locking mechanism, and a retainer ring. The hammer tool is inserted into an opening in the hammer case. The hammer tool has a spline section and a tool section, the spline section including a first spline partition and a second spline partition, the first spline partition including at least six spline grooves, the second spline partition including at least six spline grooves, the first spline partition and the second spline partition being separated by a spacer; and the tool section diameter is smaller than the spline section diameter.

[0008] According to another aspect of the present disclosure, a method for fixing a hammer tool to a hammer assembly of a working machine is disclosed. The method includes: providing the hammer assembly, the hammer assembly including a hammer case and the hammer tool, the hammer case including a hammer and a working chamber for receiving the hammer tool through an opening of the hammer case, the working chamber having a plurality of splines and a locking mechanism; providing the hammer tool having a spline section and a tool section, the spline section including a first spline partition and a second spline partition, the first spline partition including at least six spline grooves, the second spline partition including at least six spline grooves, the first spline partition and the second spline partition being separated by a spacer, the tool section having a smaller diameter than the spline section; and inserting the hammer tool into the working chamber through the opening in the hammer case; and rotating the locking mechanism around the hammer tool until it is in a locked state.

[0009] These and other aspects and features of the present disclosure will be better understood after reading the following detailed description when read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a perspective view of a work machine including a hammer assembly according to an embodiment of the present disclosure.

[0011] Figure 2 A movable arm connected to a working machine according to an embodiment of the present disclosure Figure 1 An enlarged perspective view of the hammer assembly.

[0012] Figure 3 According to the embodiment of the present disclosure Figure 2 A perspective view of a hammer assembly for use with a hammer tool.

[0013] Figure 4 According to an embodiment of the present disclosure, Figure 3 The line 4-4 is taken and shows the working chamber of the hammer assembly Figure 3 Cross-sectional view of a hammer tool.

[0014] Figure 5 According to an embodiment of the present disclosure, Figure 4 The line 5-5 is intercepted Figure 4 Cross-sectional view of the operating room.

[0015] Figure 6 is a perspective view of a hammer tool connected to a hammer assembly according to an embodiment of the present disclosure, with a working chamber depicted in phantom.

[0016] Figure 7 is a flow chart of a method for securing a hammer tool to a hammer assembly according to an embodiment of the present disclosure.

[0017] The accompanying drawings depict one embodiment of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods shown herein may be employed without departing from the principles described herein. DETAILED DESCRIPTION

[0018] Referring now to the drawings, and in the depicted example with specific reference to an exemplary work machine 100, and shown as a backhoe loader. A backhoe loader is a heavy equipment in the construction and agricultural industries designed to move earthen material from the ground or landscape at an excavation site. Although the following detailed description describes exemplary aspects related to a backhoe loader, it should be understood that the description is equally applicable to the use of the present disclosure in other work machines, including but not limited to excavators, front-end loaders, skid steer loaders, wheel loaders, and tractors.

[0019] refer to Figure 1, the work machine 100 includes a frame 102 supporting an engine 104. The frame 102 is supported on ground engaging elements 106 shown as wheels. It is contemplated that the ground engaging elements 106 may be any other type of ground engaging elements 106, such as, for example, continuous tracks, etc. The work machine 100 also includes a work mechanism 108 extending from the frame for performing work, such as, for example, breaking landscape, soil, concrete, rock or other materials at an excavation site. The frame 102 may be an upper slewing body common to excavators and work machines in the agricultural, construction and mining industries. The work mechanism 108 includes a boom 110, an arm 112, a bracket 114 and a hammer assembly 116. The hammer assembly 116 may be attached to the work mechanism 108 via the bracket 114. It will be appreciated that the hammer assembly 116 may also be attached to the work mechanism 108 via a coupler, a quick coupler or a hydraulic quick coupler as is generally known in the art.

[0020] The hammer assembly 116 may be hydraulically actuated via a hydraulic circuit (not shown) provided with the work machine 100 and connected to one or more hydraulic supply lines 118. The hydraulic circuit may raise, lower, and / or swing the arm 112 and the boom 110 to correspondingly raise, lower, and / or swing the hammer assembly 116. The work machine 100 may include a pump (not shown) connected to the hydraulic circuit and the hammer assembly 116 via one or more hydraulic supply lines 118. The hydraulic circuit may introduce a pressurized fluid (e.g., oil) from the pump and into one or more hydraulic supply line 118 cylinders and into the hammer assembly 116. Operator controls for moving and actuating the hydraulic circuit and / or the hammer assembly 116 may be located within the cab 120 of the work machine 100. A pressure control valve may be provided in the hammer assembly 116 to maintain maximum hydraulic pressure, thereby ensuring that the hammer assembly 116 delivers all blows at full power to break rocks, etc.

[0021] Reference now Figure 2 , a close-up view of a hammer assembly 116 connected to the arm 112 of the work machine 100 is shown. The hammer assembly 116 may include a hammer case 200 and a hammer tool 202. The hammer tool 202 is connected to the hammer assembly 116 and is located in a working chamber 204 inside the hammer case 200. The hammer tool 202 extends outside the hammer case 200, opposite the bracket 114, for contacting and / or breaking rock, soil, earth, ground, etc. The hammer case 200 may be a symmetrical reversible case that can be rotated 180 degrees to compensate for wear and extend the life of the hammer assembly 116.

[0022] Figure 3A perspective view of a hammer tool 202 for use with the hammer assembly 116 is depicted. The hammer tool 202 may include a shaft 300 that includes a spline section 302 and a tool section 304. The spline section 302 is generally the portion of the shaft 300 of the hammer tool 202 that is received by the hammer case 200 in the working chamber 204 of the hammer assembly 116. In contrast, the tool section 304 of the shaft 300 may generally include the portion of the hammer tool 202 that protrudes from the hammer assembly 116 and contacts the material being crushed. The spline section 302 has a larger diameter than the tool section 304.

[0023] The spline section 302 includes a first spline partition 306 and a second spline partition 308. The first spline partition 306 and the second spline partition 308 are separated by a spacer 310. The spacer 310 can be circular, square, octagonal, hexagonal, or polygonal. The first spline partition 306 and the second spline partition 308 can each include a plurality of spline grooves 312 having a spline diameter 314. The spline grooves 312 in the first spline partition 306 can be aligned with the spline grooves 312 in the second spline partition 308, respectively.

[0024] Each of the spline grooves 312 in the first spline partition 306 can be aligned with the spline grooves 312 in the second spline partition 308, and each spline groove can be hemispherical or curved. As an alternative, each of the spline grooves 312 can be square, trapezoidal or rectangular. The first spline partition 306 can include a spline groove 312, and a corresponding number of spline grooves 312 are in the second spline partition 308. In one embodiment, the first spline partition 306 and the second spline partition 308 can each include 6-12 spline grooves 312. For example, the first spline partition 306 can include between 6 and 12 spline grooves 312, and an equal number of spline grooves 312 are in the second spline partition 308. Of course, other numbers of spline grooves 312 are possible. The spline grooves 312 can be positioned equidistantly around the perimeter of the spline section 302 in both the first spline partition 306 and the second spline partition 308.

[0025] The tool section includes a tool section diameter 316, and the tool section diameter 316 can be several times the spline diameter 314. For example, the tool section diameter 316 can be 3.2 to 4.8 times the spline diameter 314, but of course these are only exemplary ranges. The first spline section 306 and the second spline section 308 can be larger in diameter than the tool section diameter 316. The larger diameters of the first spline section 306 and the second spline section 308 reduce bending stresses of the hammer tool 202 because the stresses are distributed over a larger contact area. In addition, when the spacer 310 is configured as a rounded center geometry without a tool pin notch, it provides less stress traveling through the hammer tool 202. In one embodiment, the hammer tool 202 can include a tool tip 318. The tool tip 318 can be a chisel edge, a moil point, a conical point, a spade, a compacting plate, a wedge, or other tool shapes commonly known in the art for breaking rock, soil, or other materials.

[0026] Figure 4 Provided along Figure 3 The line 4-4 is taken and illustrates the working chamber 204 of the hammer assembly 116 in one embodiment of the present disclosure. Figure 3 The working chamber 204 includes a first set of splines 400 and a second set of splines 402 separated by a locking mechanism 404. The locking mechanism 404 may also be generally referred to as a "tool stop" and is configured as a ring to be positioned around the spacer 310 of the hammer tool 202.

[0027] The first set of splines 400 corresponds to the spline grooves 312 in the first spline partition 306, and the second set of splines 402 corresponds to the spline grooves 312 in the second spline partition 308 on the hammer tool 202. The first set of splines 400 and the second set of splines 402 can be coaxially or otherwise aligned. There can be 6-12 splines in each of the first set of splines 400 and the second set of splines 402, but other numbers of splines are possible. The first set of splines 400 and the second set of splines 402 can be wear strips that are cylindrical strips, square strips, or polygonal strips.

[0028] In one embodiment, Figure 4 The hammer tool 202 is shown operably coupled to a hammer 406 inside the hammer case 200, whereby the hammer 406 is positioned above the spline section 302 of the hammer tool 202. The hammer 406 may be a piston or other hammer type that provides a reciprocating impact motion to the hammer tool 202, as is commonly known in the art.

[0029] The hydraulic circuit in the work machine 100 can be operably connected to the hammer assembly 416 and can provide pressurized fluid to cause the hammer 406 to reciprocate alternately in a work stroke and return stroke mode, as is generally known in the art. Operator controls for movement of the work mechanism 108 and / or the hammer assembly 116 can be located within the cab 120 of the work machine 100. Driven by the hydraulic supply, the hammer inside the hammer housing 200 can provide a reciprocating impact motion to the hammer tool 202, which in turn can be applied to the material in contact with the hammer tool 202, such as rock or concrete. It is contemplated that the hammer tool 202 can include any known tool capable of interacting with the hammer 406 and the ground, rock or other material. The tool section 304 or a portion thereof can enter and exit the hammer housing 200 during operation, such as when the hammer provides a reciprocating impact motion to the hammer tool 202.

[0030] There may be a thrust ring 408 around the connection point where the hammer 406 contacts the hammer tool 202. There may also be a retaining ring 410 at the end of the second set of splines 402 opposite the locking mechanism 404 for retaining the first set of splines 400 and the second set of splines 402 in the hammer assembly 116.

[0031] Reference now Figure 5 In one embodiment, it is shown along Figure 4 5-5 of FIG. 1 . The locking mechanism 404 may be configured to couple the hammer tool 202 within the hammer assembly 116. The locking mechanism 404 surrounds the spacer 310 of the hammer tool 202. The inner surface of the locking mechanism 404 that contacts the spacer 310 may include a plurality of locking indentations 500 protruding from the locking mechanism 404. The plurality of locking indentations 500 may be shaped as a cone, a trapezoid, a square, etc., wherein the spacer 310 is configured to receive the plurality of locking indentations 500. When the plurality of locking indentations 500 are aligned with the first set of splines 400 and / or the second set of splines 402, the hammer tool 202 is then in an unlocked state with the hammer assembly 116. When the locking mechanism 404 is in the unlocked state, the hammer tool 202 may be easily removed from the hammer assembly 116 for repair.

[0032] When the locking mechanism 404 is in the unlocked state, a replacement hammer tool 202 can be inserted into the working chamber 204 of the hammer assembly 116. When the locking mechanism 404 is rotated so that the plurality of locking indentations 500 are not aligned with the first set of splines 400 and / or the second set of splines 402, then the hammer tool 202 is in a locked state with the hammer assembly 116.

[0033] Reference now Figure 6, a perspective view of the work chamber 204 in one embodiment is shown. The first set of splines 400 and the second set of splines 402 are shown as circular shapes, which are most efficient for the machining process. The first set of splines 400 and the second set of splines 402 can be small enough to be handled by hand. The added surface area of ​​the first set of splines 400 and the second set of splines 402 distributes the contact stress of the hammer 406 with the hammer tool 202 among several splines. One or more of the splines can be easily replaced and / or reused. The first set of splines 400 and the second set of splines 402 can be the same strip, which reduces the number of parts required, thereby providing simplified parts storage and replacement.

[0034] The first set of splines 400 and the second set of splines 402 allow the hammer tool 202 to be rotated in the event of shear damage or wear and tear of the tool tip 318 without requiring unique parts for the specific chisel angle orientation required for breaking rock, dirt, etc. For example, Figure 6 As shown in , the tool tip 318 may be shaped as a wedge-shaped chisel tip that may be rotated so that a surface of the tool tip 318 may be at a preferred angle when contacting rock, earth, or other material during operation of the hammer assembly 116 .

[0035] Industrial Applicability

[0036] In operation, the present disclosure may be applicable to many industries, including but not limited to the construction, earthmoving, mining, and agricultural industries. Specifically, the technology of the present disclosure may be used to break various materials, such as rock, concrete, asphalt, or other earthen materials, with various work machines, including but not limited to excavators, backhoes, skid steer loaders, wheel loaders, tractors, etc. Although the foregoing detailed description is made with specific reference to backhoe loaders, it should be understood that its teachings may also be applied to other work machines that utilize hammer assemblies, such as excavators, skid steer loaders, wheel loaders, tractors, topsoil looseners, etc.

[0037] refer to Figure 1-6 The industrial applicability of the hammer tool 202 configured to be coupled to the hammer assembly 116 described herein will be readily appreciated from the foregoing discussion. According to some embodiments, the hammer assembly 116 and the hammer tool 202 may each be configured to facilitate quick and effortless coupling and / or decoupling of the hammer tool 202 from the hammer assembly 116. For example, since the hammer tool 202 is used to break hard materials such as rock, the hammer tool 202 may experience significant wear and require quick replacement and easier maintenance with a new hammer tool 202 at a job site.

[0038] Additionally, a hammer tool 202 configured with one type of tool tip 318 (e.g., a chisel edge) may be exchanged for another hammer tool 202 with a different type of tool tip 318 (e.g., a compaction plate) depending on job site requirements and the material to be broken.

[0039] When the locking mechanism 404 is in the unlocked state, the hammer tool 202 can be inserted into the working chamber 204 of the hammer assembly 116. When the operator has inserted the hammer tool 202 into the working chamber 204 of the hammer assembly 116, the locking mechanism 404 can be rotated to the locked state, in which the hammer tool 202 is securely coupled to the hammer case 200. The operator can rotate the locking mechanism 404 to the locked state. In the locked state, the spline grooves 312 in the first spline partition 306 are misaligned with the locking indents 500, and thus the locking indents 500 are also misaligned with the first set of splines 400 and the second set of splines 402. Due to the misalignment, the hammer tool 202 can remain in the working chamber 204 of the hammer assembly 116 and is therefore operably coupled to the hammer case 200.

[0040] Reference now Figure 7 , a method 700 of fixing a hammer tool 202 to a hammer assembly 116 of a work machine 100 is disclosed. In a first step 702, a hammer assembly 116 having a hammer case 200 and a hammer tool 202 is provided, the hammer case 200 having a hammer 406 and a working chamber 204 for receiving the hammer tool 202 through an opening of the hammer case 200, the working chamber 204 having a first set of splines 400, a second set of splines 402, and a locking mechanism 404. In step 704, the hammer tool 202 is configured to have a spline section 302 and a tool section 304, the spline section 302 including a first spline partition 306 having at least six spline grooves 312 and a second spline partition 308 having at least six spline grooves 312, the first spline partition 306 and the second spline partition 308 being separated by a spacer 310, and the tool section 304 having a smaller diameter than the spline section 302. In step 706, the hammer tool 202 is inserted into the working chamber 204 through the opening in the hammer case 200. In the final step 708, the locking mechanism is rotated about the hammer tool until it is in a locked state.

[0041] From the foregoing it can be seen that the technology disclosed herein has industrial applicability in a variety of environments, such as, but not limited to, work machines in the construction, mining and agricultural industries that utilize hammer assemblies for breaking rock, earth or other materials using work tools.

Claims

1. A tool for a hydraulic hammer (406) of a working machine (100), the tool comprising: a spline section (302), the spline section comprising a first spline partition (306) and a second spline partition (308), the first spline partition comprising at least six spline grooves (312), the second spline partition comprising at least six spline grooves (312), the first spline partition (306) and the second spline partition (308) being separated by a spacer (310); and A tool section (304) having a tool section diameter (316) that is smaller than a spline section (302) diameter.

2. The tool of claim 1, wherein the spline section (302) comprises 6-12 spline grooves (312) in the first spline partition (306) and 6-12 spline grooves (312) in the second spline partition (308), and the tool section diameter (316) is 3.2-4.8 times the spline groove diameter; The spacer portion (310) has a smaller diameter than the first spline section (306) and the second spline section (308), and the spacer portion (310) is configured to be circumferentially shaped into a square, an octagon, or a polygon; and The tool section (304) includes a tool tip (318) opposite the spline section (302), the tool tip (318) being selected from the group consisting of a chisel edge, a pick tip, a conical tip, a spade, a compacting plate, and a wedge.

3. The tool according to claim 1, wherein the at least six spline grooves (312) in the first spline partition (306) are aligned with the at least six spline grooves (312) in the second spline partition (308).

4. According to the tool according to claim 1, the at least six spline grooves (312) in the first spline partition (306) and the at least six spline grooves (312) in the second spline partition (308) are configured to receive cylindrical bars, conical bars, square bars or polygonal bars, and the at least six spline grooves (312) in the first spline partition (306) have a diameter that matches or is different from the at least six spline grooves (312) in the second spline partition (308).

5. A hammer assembly (116), comprising: Hammer (406); Hammer housing (200); and The working chamber (204) in the hammer case (200) has a plurality of splines (400), a locking mechanism (404), and a retainer ring; a hammer tool (202) is inserted into the working chamber (204) through an opening in the hammer case (200), the hammer tool (202) includes a spline section (302) and a tool section (304), the spline section (302) includes a first spline partition (306) and a second spline partition (308), the first spline partition includes at least six spline grooves (312), the second spline partition includes at least six splines (400), the first spline partition (306) and the second spline partition (308) are separated by a spacer (310), and the tool section (304) has a tool section diameter (316), and the tool section diameter (316) is smaller than the spline section (302) diameter.

6. The hammer assembly (116) of claim 5, further comprising: The locking mechanism (404) separates a first spline set and a second spline set, the first spline set having 6-12 splines (400) and the second spline set having 6-12 splines (400); The first spline partition (306) has 6-12 spline grooves (312) configured to receive the first spline set, and the second spline partition (308) has 6-12 spline grooves (312) configured to receive the second spline set; The tool section diameter (316) is 3.2-4.8 times the spline groove diameter; The hammer assembly (116) is hydraulically powered; and The hammer tool (202) is freely rotatable.

7. The hammer assembly (116) of claim 6, wherein the locking mechanism (404) is a ring having a locking indentation (500) disposed across an interior of the locking mechanism (404) and configured to rotate about the spacer (310) from a locked state and an unlocked state, whereby the locked state couples the hammer tool (202) to the hammer case (200); The locking indentation (500) is a locking indentation selected from a conical shape, a square shape and a trapezoidal shape; and The tool section (304) includes a tool tip (318) opposite the spline section (302), and the tool tip (318) is selected from the group consisting of a chisel edge, a pick tip, a conical tip, a spade, a compacting plate, and a wedge.

8. The hammer assembly (116) of claim 7, wherein the plurality of splines (400) are wear strips, and the first spline set is a conical wear strip, and the second spline set is a polygonal wear strip, whereby the first spline section (306) and the second spline section (308) are each configured to receive the first spline set and the second spline set, respectively.

9. The hammer assembly (116) of claim 7, the first spline set received by the first spline section (306) of the hammer tool (202) being axially aligned with the second spline set received by the second spline section (308) of the hammer tool (202).

10. The hammer assembly (116) of claim 9, the hammer assembly (116) being coupled to a bracket (114) of a work machine (100), the work machine (100) comprising: Frame (102); ground engaging elements supporting the frame (102); an engine (104) in the frame (102) and powering the work machine (100); an operating mechanism (108) extending from the frame (102); hydraulic circuits; and The bracket (114) is on the end of the working mechanism (108).

11. A method (700) of securing and retaining a hammer tool (202) to a hammer assembly (116) of a work machine (100), the method (700) comprising: The hammer assembly (116) is provided, the hammer assembly comprising a hammer case (200) and the hammer tool (202), the hammer case (200) comprising a hammer (406) and a working chamber (204) for receiving the hammer tool (202) through an opening of the hammer case (200), the working chamber (204) having a plurality of splines (400) and a locking mechanism (404); The hammer tool (202) is configured to have a spline section (302) and a tool section (304), the spline section (302) including a first spline partition (306) having at least six spline grooves (312) and a second spline partition (308) having at least six spline grooves (312), the first spline partition (306) and the second spline partition (308) being separated by a spacer (310), and the tool section (304) having a smaller diameter than the spline section (302); inserting the hammer tool (202) into the working chamber (204) through the opening in the hammer housing (200); as well as The locking mechanism (404) is rotated around the hammer tool (202) until it is in a locked state.

12. The method (700) according to claim 11, further comprising: operating the hammer assembly (116) on earthen material until the hammer tool (202) is worn; Rotating the locking mechanism (404) around the hammer tool (202) until it is in an unlocked state; removing the hammer tool (202) from the working chamber (204) through the opening and away from the hammer housing (200); inserting a replacement hammer tool (202) into the working chamber (204) through the opening in the hammer housing (200); as well as The locking mechanism (404) is rotated around the replacement hammer tool (202) until it is in a locked state.

13. The method (700) of claim 11, further comprising: operating the hammer assembly (116) against earthen material using a tool tip (318) of the hammer tool (202) until the tool tip (318) is cut; and The hammer tool (202) is rotated so that the tool tip (318) is in a preferred position for contacting the earthen material during operation of the hammer assembly (116).

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