Patent Description:
Hydraulic hammers are used at various work sites for breaking up hard objects, such as rocks, concrete, asphalt, frozen ground, and other materials. The hydraulic hammers may be mounted on a machine, such as an excavator, a dozer, a loader, a motor grader, and the like. Typically, the hydraulic hammers include a housing, a power cell enclosed within the housing, and a mounting bracket disposed on the housing. The power cell is positioned within the housing and coupled with a tool that extends out of the housing. The power cell may be operated pneumatically or hydraulically for actuating the tool for performing various operations on a work surface. The power cell generally includes a valve assembly for regulating fluid flow to and from the power cell. Some power cells may have an external valve assembly.

The power cell may have to be removed from the housing of the hydraulic hammer for servicing and/or replacement. Hydraulic hammers with external valve assembly may require removal of multiple parts, for example, pins, wear members, and the mounting bracket, to remove the power cell from the housing. This may result in additional downtime and requirement of various tools to service and/or replace the power cell.

<CIT> describes an improved breaker which has improvement points with respect to a control valve structure for a breaker, a piston structure for a breaker having an actuating surface using an inclination structure, and a gas chamber structure for expanding the capacity thereof. The control valve for a breaker, which is installed in a valve room to switch the direction of fluid in a breaker, includes: a valve housing; a valve spool which is fitted to come in contact with the inner surface of the valve housing; and a valve plug which is fitted to come in contact with the inner surface of the valve spool.

<CIT> discloses a demolition hammer including a housing having a distal end and a proximal end, a power cell disposed in the housing along a longitudinal axis and a side buffer positioned to support the power cell in the housing, wherein the housing forms a first retaining structure that prevents axial movement of the side buffer toward the proximal end. The housing may also form a second retaining structure that prevents inward radial movement of the side buffer and a third retaining structure that prevents outward radial movement of the side buffer.

According to the invention as defined in claim <NUM>, a hydraulic hammer is provided. The hydraulic hammer includes a housing defining a cutout and a power cell slidably received within the housing. The power cell includes a valve assembly extending from a side of the power cell. The valve assembly is at least partially received within the cutout of the housing. The hydraulic hammer further includes a pair of wear plates at least partially disposed around the valve assembly of the power cell. Each of the pair of wear plates is coupled to the power cell.

Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. Referring to <FIG>, an exemplary machine <NUM> employing a hydraulic hammer <NUM> (hereinafter referred to as "the hammer <NUM>") is illustrated. The machine <NUM> may be an excavator (shown in <FIG>), a backhoe loader, a skid steer loader, dozer, a motor grader, or any other type of machine. The machine <NUM> may perform work associated with a particular industry including, but not limited to, construction, mining, agriculture, waste management, material handling, and forestry.

The machine <NUM> includes linkages, such as a boom <NUM> and a stick <NUM>. The boom <NUM> is pivotally connected to a frame <NUM> of the machine <NUM>. Further, the stick <NUM> is pivotally connected to the boom <NUM>. A mounting bracket <NUM> pivotally connects the hammer <NUM> to the stick <NUM>. The hammer <NUM> may replace an excavator bucket.

The machine <NUM> includes a drive system <NUM>, such as tracks, for propelling the machine <NUM>. The frame <NUM> is rotatable about a vertical axis (not shown) with respect to the drive system <NUM>. The machine <NUM> further includes an operator cab <NUM> having user interface devices for controlling the boom <NUM>, the stick <NUM>, the drive system <NUM>, and the hammer <NUM>. One or more hydraulic cylinders <NUM> may raise, lower, and/or swing the boom <NUM>, the stick <NUM>, and the mounting bracket <NUM> to correspondingly raise, lower, and/or swing the hammer <NUM>.

The hammer <NUM> includes a work tool <NUM> that may be operated to break up or demolish hard objects, such as rocks, concrete, asphalt, frozen ground, and other materials. It is contemplated that the work tool <NUM> may include any tool capable of use with the hammer <NUM>. In one embodiment, work tool <NUM> may include a chisel bit. Further, the hammer <NUM> may be powered hydraulically, pneumatically, or a combination thereof for actuation of the work tool <NUM>.

<FIG> illustrates a perspective view of the hammer <NUM>. The hammer <NUM> includes a housing <NUM> that encloses one or more components of the hammer <NUM>. The housing <NUM> defines a longitudinal axis 'L' along its length. Further, the housing <NUM> defines a top end <NUM> and a bottom end <NUM> with respect to the longitudinal axis 'L'. The housing <NUM> includes a top flange <NUM> at the top end <NUM> and a bottom flange <NUM> at the bottom end <NUM>. The top flange <NUM> is detachably coupled to the mounting bracket <NUM> via multiple fasteners <NUM>. Further, the work tool <NUM> extends through the bottom flange <NUM>.

The housing <NUM> also includes a front external wall <NUM> (hereinafter referred to as "the external wall <NUM>"), a pair of side walls <NUM> disposed opposite to one another, and a rear wall <NUM> (shown in <FIG> and <FIG>) disposed opposite to the external wall <NUM>. The external wall <NUM> defines a front opening <NUM> (shown in <FIG>) extending therethrough. The external wall <NUM> is located between the side walls <NUM>. Further, the side walls <NUM> may extend beyond the external wall <NUM>. The front opening <NUM> is covered by a dust cover <NUM> that defines a pair of cover holes <NUM>. Each of the cover holes <NUM> may receive a fluid conduit (not shown) therethrough. The fluid conduits may provide supply and discharge paths for a working fluid of the hammer <NUM>. The housing <NUM> further includes a pair of top reinforcing portions <NUM> connected to the top flange <NUM> and each of the side walls <NUM>. In an embodiment, the top reinforcing portions <NUM> may be welded to the top flange <NUM> and the corresponding side wall <NUM>. Each of the top reinforcing portions <NUM> may have a substantially triangular shape. Each of the side walls <NUM> includes a side handling portion <NUM> connected to the bottom flange <NUM>. A bottom handling portion <NUM> is further connected to the external wall <NUM> and the bottom flange <NUM>. In an embodiment, the bottom handling portion <NUM> may be welded to the external wall <NUM> and the bottom flange <NUM>. Each of the side and bottom handling portions <NUM>, <NUM> may have a substantially triangular shape. The side and bottom handling portions <NUM>, <NUM> may point towards the operator cab <NUM> (shown in <FIG>) of the machine <NUM> and are used for material handling.

In various embodiments, different parts of the housing <NUM> may be connected to each other by various methods, such as welding, brazing, adhesives, mechanical fasteners, and the like. In an alternative embodiment, the housing <NUM> may include a one-piece configuration. Further, the housing <NUM> may be made of a metal, an alloy, a plastic, a composite, or any other suitable material.

<FIG> illustrates an exploded view of the hammer <NUM>. Several components of the hammer <NUM>, such as the work tool <NUM> and the dust cover <NUM>, have been omitted in <FIG> for the purpose of clarity. The hammer <NUM> includes a power cell <NUM> that is slidably and removably received within the housing <NUM>. Specifically, the power cell <NUM> may be slidably received within or removed from the housing <NUM> along an axial direction 'D'. The axial direction 'D' may be substantially parallel to the longitudinal axis `L' of the housing <NUM>. The power cell <NUM> includes a main housing <NUM> and a valve assembly <NUM>. The main housing <NUM> defines a first end <NUM> and a second end <NUM> opposite to the first end <NUM>. In the illustrated embodiment, the main housing <NUM> has a substantially rectangular cross-section. However, the main housing <NUM> may have any other suitable shape as per application requirements. The main housing <NUM> may enclose one or more working components of the power cell <NUM> for actuating the work tool <NUM> (shown in <FIG>). Specifically, power cell <NUM> may include a piston <NUM> (shown schematically in <FIG>) disposed inside the main housing <NUM> and other components (not shown). The piston <NUM> may reciprocate inside the main housing <NUM> during operation of the hammer <NUM>. The power cell <NUM> may further include a bottom part <NUM> extending from the second end <NUM> of the housing <NUM>. The work tool <NUM> may extend from the bottom part <NUM>. Further, the work tool <NUM> may be operatively connected to the power cell <NUM> at the bottom part <NUM>. In an embodiment, the bottom part <NUM> may have a hollow cylindrical shape. The power cell <NUM> further includes multiple nut and bolt assemblies <NUM> that project from the first end <NUM> of the main housing <NUM>. The nut and bolt assemblies <NUM> may retain various components of the power cell <NUM> within the main housing <NUM>.

The valve assembly <NUM> extends from a side <NUM> of the main housing <NUM>. Specifically, the valve assembly <NUM> may extend transversely from the side <NUM> of the main housing <NUM>. The valve assembly <NUM> may regulate flow of the working fluid to and from the power cell <NUM> in order to actuate the piston <NUM>. The valve assembly <NUM> may therefore constitute an external valve assembly of the power cell <NUM>, i.e., the valve assembly <NUM> is disposed externally to the main housing <NUM>. The valve assembly <NUM> includes a main portion <NUM> and a pair of securing members <NUM> disposed at opposite ends of the main portion <NUM>. The main portion <NUM> may form a valve housing and encloses one or more components of the valve assembly <NUM>. The main portion <NUM> may be connected to the main housing <NUM> of the power cell <NUM> via multiple first fasteners <NUM>. Further, each of the securing member <NUM> in cooperation with multiple second fasteners <NUM> may retain various components within the main portion <NUM> of the valve assembly <NUM>. The valve assembly <NUM> further includes a pair of fluid connectors <NUM> disposed on the main portion <NUM>. The fluid connectors <NUM> may connect with corresponding fluid conduits for intake and discharge of the working fluid from the valve assembly <NUM>. The main housing <NUM> of the power cell <NUM> further defines multiple apertures <NUM> around the valve assembly <NUM>. The multiple apertures <NUM> may receive a pair of wear plates <NUM>. The wear plates <NUM> are at least partially disposed around the valve assembly <NUM> of the power cell <NUM>.

The housing <NUM> further includes an internal wall <NUM> spaced apart from the external wall <NUM>. The internal wall <NUM> defines a cutout <NUM>. The valve assembly <NUM> is at least partially received within the cutout <NUM> upon insertion of the power cell <NUM> within the housing <NUM>. Further, the valve assembly <NUM> extends through the cutout <NUM> towards the external wall <NUM> upon insertion of the power cell <NUM> within the housing <NUM>. In the illustrated embodiment, the cutout <NUM> is U-shaped. However, the cutout <NUM> may have any other alternative shape based on the shape of the valve assembly <NUM>. The cutout <NUM> and the front opening <NUM> may be substantially aligned with each other such that the fluid conduits received through the cover holes <NUM> (shown in <FIG>) of the dust cover <NUM> may be attachable to the corresponding fluid connectors <NUM> of the valve assembly <NUM>. The external wall <NUM> along with the dust cover <NUM> may therefore act as a cover for the valve assembly <NUM>.

The housing <NUM> further defines a house opening <NUM> originating at the top end <NUM> for receiving the power cell <NUM> within the housing <NUM>. The house opening <NUM> includes a first portion <NUM> and a second portion <NUM> adjacent to the fist portion <NUM>. The first portion <NUM> may receive the main housing <NUM> of the power cell <NUM>. Further, the second portion <NUM> may receive the valve assembly <NUM> of the power cell <NUM>. The first and second portions <NUM>, <NUM> of the house opening <NUM> may extend at least partially along the length of the housing <NUM>. Each of the first portion <NUM> and the second portion <NUM> has a substantially rectangular shape. However, an area of the first portion <NUM> is larger than an area of the second portion <NUM>.

The top flange <NUM> further defines multiple flange apertures <NUM>. The mounting bracket <NUM> also defines corresponding bracket apertures <NUM>. The flange apertures <NUM> and the corresponding bracket apertures <NUM> receive the corresponding fasteners <NUM> for removably securing the mounting bracket <NUM> to the top flange <NUM> of the housing <NUM>. The hammer <NUM> further includes a top buffer <NUM> that is disposed proximate to the top end <NUM> of the housing <NUM>. In an embodiment, the top buffer <NUM> may be retained between the mounting bracket <NUM> and the top flange <NUM> of the housing <NUM>. The top buffer <NUM> may further rest on a top surface <NUM> of the main housing <NUM> of the power cell <NUM>. The top buffer <NUM> includes multiple recessed portions <NUM> for accommodating the nut and bolt assemblies <NUM> extending from the top surface <NUM> of the power cell <NUM>. The top buffer <NUM> further defines a hole <NUM> extending therethrough.

The cutout <NUM> may allow the power cell <NUM> to be easily inserted into or removed from the housing <NUM>. Specifically, the valve assembly <NUM> may slide into the cutout <NUM> upon insertion of the power cell <NUM> into the housing <NUM>. In order to remove the power cell <NUM> from the housing <NUM>, the mounting bracket <NUM> may have to be disconnected and removed from the top flange <NUM> of the housing <NUM>. The top buffer <NUM> which rests on the top surface <NUM> of the power cell <NUM> may be easily removed without using any tools. The power cell <NUM> including the valve assembly <NUM> may be then slidably removed from the housing <NUM>.

<FIG> shows a schematic view of the power cell <NUM>. Referring to <FIG> and <FIG>, the power cell <NUM> includes the piston <NUM> that reciprocates within the main housing <NUM>. The piston <NUM> may further impact the work tool <NUM> (shown in <FIG>) during operation of the hammer <NUM>. The piston <NUM> may be actuated by a controlled flow of the working fluid to and from the power cell <NUM>. The valve assembly <NUM> may regulate the flow of the working fluid to one or more fluid chambers (not shown) associated with the piston <NUM> via fluid passages <NUM> and <NUM>. Specifically, the valve assembly <NUM> may provide pressurized working fluid to drive the piston <NUM> towards the work tool <NUM> during a work stroke and to return the piston <NUM> during a return stroke. In various embodiments, the valve assembly <NUM> may include one or more valves (not shown) to control the flow of the working fluid. The valves may be mechanically operated valves, electronically controlled valves, pilot operated valves, and so forth.

The valve assembly <NUM> is further fluidly connected to a hydraulic system <NUM> of the machine <NUM> (shown in <FIG>) via fluid lines <NUM> and <NUM>. The valve assembly <NUM> may be fluidly connected to the fluid lines <NUM> and <NUM> via the fluid connectors <NUM>. The hydraulic system <NUM> may include a tank <NUM> and a pump <NUM>. The pump <NUM> is in fluid communication with the tank <NUM>. The hydraulic system <NUM> may be powered by a power source (not shown) of the machine <NUM>. The hydraulic system <NUM> may also include additional components (not shown), for example, one or more valves, filters, sensors, and so forth. The fluid line <NUM> may supply pressurized working fluid to the valve assembly <NUM> from the pump <NUM>. The fluid line <NUM> may provide a return path of the working fluid from the valve assembly <NUM> to the tank <NUM>.

<FIG> illustrates a perspective view of the housing <NUM>. The wear plates <NUM> may be disposed around the cutout <NUM> defined by the internal wall <NUM>. Each of the wear plates <NUM> is coupled to the power cell <NUM> (shown in <FIG>). In an embodiment which is not according to the claimed invention, each of the wear plates <NUM> may be detachably coupled to the internal wall <NUM> of the housing <NUM> by various methods, such as fasteners, pegs, a snap-fit connection, and so forth. A middle buffer <NUM> of the hammer <NUM> is also disposed within the housing <NUM>. The middle buffer <NUM> may be coupled to the rear wall <NUM> and/or side walls <NUM> of the housing <NUM>. The middle buffer <NUM> may have any suitable shape as per application requirements. The top buffer <NUM> is disposed proximate to the top end <NUM> of the housing <NUM>.

The external wall <NUM> is spaced apart from the internal wall <NUM>. Further, the external wall <NUM> includes a top portion <NUM>, an inclined portion <NUM>, and a bottom portion <NUM>. The top portion <NUM> is proximal to the top end <NUM> of the housing <NUM>. The bottom portion <NUM> is proximal to the bottom end <NUM> of the housing <NUM>. The bottom handling portion <NUM> is further located in the bottom portion <NUM> of the external wall <NUM>. The inclined portion <NUM> is disposed between the top portion <NUM> and the bottom portion <NUM>. The top portion <NUM> and the bottom portion <NUM> may extend substantially parallel to the longitudinal axis 'L' of the housing <NUM>. The inclined portion <NUM> may be inclined at an angle with respect to the longitudinal axis 'L'. Each of the side walls <NUM> also includes a sloped portion <NUM> located on a side of the inclined portion <NUM>. Each of the sloped portions <NUM> may also be inclined at an angle with respect to the longitudinal axis 'L'.

<FIG> illustrates a partial perspective view of the housing <NUM> with a part of the external wall <NUM> removed. Specifically, the top and inclined portions <NUM>, <NUM> of the external wall <NUM> have been removed for illustrative purposes. The internal wall <NUM> includes a pair of elongate portions <NUM> extending from an upper edge <NUM>. The elongate portions <NUM> and the upper edge <NUM> together define the cutout <NUM>. Each of the elongate portions <NUM> may have a rectangular shape. The interface between each of the elongate portions <NUM> and the upper edge <NUM> may be rounded to provide the cutout <NUM> with a U-shape. A pair of lateral members <NUM> (only one shown in <FIG>) may extend transversely from the internal wall <NUM> towards the rear wall <NUM>. Specifically, each of the lateral members <NUM> may extend from the corresponding elongate portion <NUM> of the internal wall <NUM>. The lateral members <NUM> may guide the valve assembly <NUM> (shown in <FIG>) during insertion or removal of the power cell <NUM> from the housing <NUM>.

<FIG> and <FIG> illustrate different sectional views of the housing <NUM>. The top buffer <NUM> is disposed at the top end <NUM> of the housing <NUM>. Referring to <FIG> and <FIG>, a pair of bottom buffers <NUM> of the hammer <NUM> is disposed proximate to the bottom end <NUM> of the housing <NUM>. However, the hammer <NUM> may have any number of bottom buffers <NUM> as per application requirements. Each of the bottom buffers <NUM> may be disposed adjacent to a support portion <NUM> of the housing <NUM>. The support portion <NUM> is further disposed on the bottom flange <NUM> of the housing <NUM>. The bottom buffers <NUM> are disposed opposite to each other. The bottom buffers <NUM> may be removably coupled to one or more parts of the housing <NUM> by various methods, such as mechanical fasteners, a snap-fit connection, and the like. One of the bottom buffers <NUM> may be removably coupled to the rear wall <NUM>. The other bottom buffer <NUM> may be removably coupled to the bottom portion <NUM> of the external wall <NUM>. Each of the bottom buffers <NUM> may have any suitable shape as per application requirements. In an embodiment, each of the bottom buffers <NUM> may be chamfered at both top and bottom ends.

The middle buffer <NUM> is disposed between the top buffer <NUM> and one of the bottom buffers <NUM> with respect to the longitudinal axis 'L' of the housing <NUM>. The middle buffer <NUM> may be removably coupled to the rear wall <NUM> of the housing <NUM>. Further, the middle buffer <NUM> may be located opposite to the cutout <NUM> and the wear plates <NUM> (only one shown in <FIG>). In an embodiment, the middle buffer <NUM> may be chamfered at both top and bottom ends. In another embodiment, the middle buffer <NUM> and each of the bottom buffers <NUM> may have a substantially similar configuration. The top, middle, and bottom buffers <NUM>, <NUM>, <NUM> and the wear plates <NUM> may form a buffer system of the hammer <NUM>.

Each of the top, middle, and bottom buffers <NUM>, <NUM>, <NUM> may act as a sacrificial material, and prevent the components of the power cell <NUM> from being subjected to wear and abrasion during operation of the hammer <NUM>. The top, middle, and bottom buffers <NUM>, <NUM>, <NUM> may further isolate at least a part of the power cell <NUM> from the housing <NUM>. Specifically, the top, middle, and bottom buffers <NUM>, <NUM>, <NUM> may isolate the main housing <NUM> of the power cell <NUM> from the housing <NUM>. The top, middle, and bottom buffers <NUM>, <NUM>, <NUM> may also protect inner surfaces of the housing <NUM> by presenting a sacrificial surface. Similarly, the wear plates <NUM> may protect the valve assembly <NUM> from wear and abrasion during operation of the hammer <NUM>. Each of the top, middle, and bottom buffers <NUM>, <NUM>, <NUM> may be made of a non-metallic material, for example, but not limited to, rubber, urethane, nylon, ultra-high-molecular-weight polyethylene (UHMW), and so forth.

The housing <NUM> further includes a bottom opening <NUM> disposed at the bottom end <NUM>. The bottom opening <NUM> is defined by the bottom flange <NUM> and extends therethrough. The support portion <NUM> also defines a support opening <NUM> extending therethrough. The support opening <NUM> may be axially aligned with the bottom opening <NUM> of the bottom flange <NUM>. The work tool <NUM> (shown in <FIG>) extends through the bottom opening <NUM>. Further, the side walls <NUM> extend beyond the external wall <NUM> along a direction that is perpendicular to the longitudinal axis `L' of the housing <NUM>. Further, the front opening <NUM> may be substantially aligned with the cutout <NUM>. The side walls <NUM> may also extend beyond the rear wall <NUM> along a direction that is perpendicular to the longitudinal axis `L' of the housing <NUM>. The rear wall <NUM> may be disposed between the side walls <NUM>.

The housing <NUM> further defines a hollow volume for slidably receiving the power cell <NUM> therein. The house opening <NUM> may extend at least partially along the length of the housing <NUM> to define the hollow volume. The first portion <NUM> of the house opening <NUM> may extend from the top end <NUM> of the housing <NUM> to the support portion <NUM>. The main housing <NUM> (shown in <FIG>) of the power cell <NUM> is received within the first portion <NUM>. The valve assembly <NUM> may be slidably inserted or removed through the second portion <NUM> of the house opening <NUM>. The second portion <NUM> may extend from the top end <NUM> of the housing <NUM> to an upper edge of the inclined portion <NUM> of the external wall <NUM>. Therefore, a width of the hollow volume defined by the housing <NUM> varies along the longitudinal axis 'L'. The hollow volume may have a first width 'W1' till the upper edge of the inclined portion <NUM>. Further, the hollow volume may have a second width 'W2' from a lower edge of the inclined portion <NUM> to the support portion <NUM>. The first width 'W1' may be larger than the second width 'W2'. The first width 'W I' may accommodate both the main housing <NUM> and the valve assembly <NUM> of the power cell <NUM>. The second width 'W2' may accommodate only the main housing <NUM> of the power cell <NUM>. The inclined portion <NUM> of the external wall <NUM> and the sloped portions <NUM> of the side walls <NUM> may act as a transition region between the first width 'W1' and the second width 'W2'. Further, the support opening <NUM> has a third width 'W3'. The support opening <NUM> may at least partially receive the bottom part <NUM> (shown in <FIG>) of the power cell <NUM>.

Upon insertion within the housing <NUM>, the valve assembly <NUM> extends through the cutout <NUM> towards the external wall <NUM>. Specifically, the valve assembly <NUM> extends into a space <NUM> defined between the internal wall <NUM> and the external wall <NUM>. The internal wall <NUM> further extends upwards from the lower edge of the inclined portion <NUM> of the external wall <NUM>. In an embodiment, the internal wall <NUM> may be integral with the bottom portion <NUM> of the external wall <NUM>. In another embodiment, the internal wall <NUM> may be joined to the bottom portion <NUM>.

<FIG> illustrates the power cell <NUM> being partially inserted into the housing <NUM>. A part of the external wall <NUM> has been removed for the purpose of illustration. The power cell <NUM> may be inserted substantially parallel to the axial direction 'D'. The main housing <NUM> of the power cell <NUM> defines two pairs of the apertures <NUM>. The apertures <NUM> are disposed around the valve assembly <NUM>. Specifically, one of the pair of apertures <NUM> are disposed on one side of the valve assembly <NUM>, while the other pair of apertures <NUM> are disposed on the opposite side. Each of the pair of apertures <NUM> are coupled to the corresponding wear plate <NUM> (shown in <FIG>). In an embodiment, the apertures <NUM> may be drilled into the main housing <NUM>. The cutout <NUM> may allow the valve assembly <NUM> to be inserted into or removed from the housing <NUM>. Further, the valve assembly <NUM> is at least partially received in the cutout <NUM> upon insertion within the housing <NUM>.

<FIG> illustrates the power cell <NUM> fully inserted within the housing <NUM>. A part of the external wall <NUM> has been removed for the purpose of illustration. In the inserted state, the valve assembly <NUM> is at least partially received within the cutout <NUM>. Further, the valve assembly <NUM> may extend through the cutout <NUM>. The top buffer <NUM> is disposed on the power cell <NUM>.

<FIG> illustrates a sectional view of the power cell <NUM> fully inserted within the housing <NUM>. Various internal components of the power cell <NUM> have been omitted for the purpose of illustration. Referring to <FIG> and <FIG>, the main housing <NUM> of the power cell <NUM> is received within the first portion <NUM> of the house opening <NUM>. The valve assembly <NUM> is at least partially received within the cutout <NUM> and extends into the space <NUM> defined between the internal wall <NUM> and the external wall <NUM>. The bottom part <NUM> is at least partially received within the support opening <NUM> of the support portion <NUM>. The top buffer <NUM> is disposed on the top surface <NUM> of the main housing <NUM>. The middle and bottom buffers <NUM>, <NUM> abut the main housing <NUM> of the power cell <NUM>. In an embodiment, the middle and bottom buffers <NUM>, <NUM> may be removably coupled to the main housing <NUM>.

<FIG> illustrates a front view of the valve assembly <NUM>. The wear plates <NUM> at least partially surround the valve assembly <NUM> on opposite sides. Each of the wear plates <NUM> includes an elongate section <NUM> and a pair of lateral sections <NUM> extending from opposite ends of the elongate section <NUM>. The pair of lateral sections <NUM> may be oriented substantially perpendicular to the elongate section <NUM>. Each of the lateral sections <NUM> includes a projecting portion <NUM> that is adapted to be removably received within the corresponding aperture <NUM> (shown in <FIG>) of the main housing <NUM>. Therefore, each of the pair of wear plates <NUM> includes a pair of the projecting portions <NUM> adapted to be removably received within the corresponding apertures <NUM> of the main housing <NUM> of the power cell <NUM>. In an embodiment, the wear plates <NUM> may be connected to the power cell <NUM> prior to insertion within the housing <NUM>. In another embodiment, the wear plates <NUM> may be connected to the power cell <NUM> upon insertion of the power cell <NUM> within the housing <NUM>. In an alternative embodiment which is not according to the claimed invention, the wear plates <NUM> may be removably attached to the internal wall <NUM> (shown in <FIG>) of the housing <NUM>.

The main portion <NUM> of the valve assembly <NUM> further includes a pair of longitudinal edges <NUM> opposite to each other and a pair of lateral edges <NUM> opposite to each other. The elongate section <NUM> of each of the wear plates <NUM> is proximal to the corresponding longitudinal edge <NUM> of the main portion <NUM>. Further, the elongate section <NUM> of each of the wear plates <NUM> may be oriented substantially parallel to the corresponding longitudinal edge <NUM> of the main portion <NUM>. The lateral sections <NUM> of each of the wear plates <NUM> are proximal to the corresponding lateral edges <NUM> of the main portion <NUM>. Further, the lateral sections <NUM> of each of the wear plates <NUM> are oriented substantially parallel to the corresponding lateral edges <NUM> of the main portion <NUM>.

The wear plates <NUM> may protect the valve assembly <NUM> from wear and abrasion during operation of the hammer <NUM>. Further, the wear plates <NUM> may retain the valve assembly <NUM> in place. Each of wear plates <NUM> may be made of a non-metallic material, for example, but not limited to, rubber, urethane, nylon, ultra-high-molecular-weight polyethylene (UHMW), and so forth.

The main portion <NUM> of the valve assembly <NUM> further defines six first apertures <NUM> and two second apertures <NUM>. Three of the first apertures <NUM> and one of the second apertures <NUM> are arranged in a column proximal to one of the longitudinal edges <NUM> of the main portion <NUM>. Similarly, the other three of the first apertures <NUM> and the other second aperture <NUM> are arranged in another column proximal to the other longitudinal edge <NUM> of the main portion <NUM>. Further, the arrangement of the first apertures <NUM> and the second aperture <NUM> in one column is reversed with respect to the other column. Specifically, the second aperture <NUM> is located at the top in one column, while the second aperture <NUM> is located at the bottom in another column. Each of the first apertures <NUM> receives the corresponding first fastener <NUM>. The first fasteners <NUM> may couple the main portion <NUM> of the valve assembly <NUM> to the main housing <NUM> of the power cell <NUM>. Each of the second apertures <NUM> receives the corresponding fluid connector <NUM>.

<FIG> illustrates a perspective view of one of the wear plates <NUM>. The elongate section <NUM> may have a rectangular shape. Each lateral section <NUM> of the wear plate <NUM> includes a chamfered region <NUM> that extends from a corresponding end <NUM> of the wear plate <NUM>. The projecting portions <NUM> are located on a surface that faces the main housing <NUM> (shown in <FIG>) of the power cell <NUM>. Further, the chamfered regions <NUM> and the projecting portions <NUM> are located on opposite surfaces. Each of the projecting portions <NUM> may have a cylindrical shape. Further, each of the projecting portions <NUM> may be embodied as pegs that are removably received within the corresponding aperture <NUM> (shown in <FIG>) of the power cell <NUM>.

<FIG> illustrate different views of a buffer member <NUM>. In an embodiment, the buffer member <NUM> may act as both the middle buffer <NUM> and each of the bottom buffers <NUM> (shown in <FIG>) of the hammer <NUM>. The buffer member <NUM> includes a top buffer end <NUM> and a bottom buffer end <NUM>. The buffer member <NUM> includes chamfered portions <NUM> at each of the top and bottom buffer ends <NUM>, <NUM>. The buffer member <NUM> further includes a main body <NUM> defining a pair of lateral recesses <NUM> opposite to each other. The buffer member <NUM> further includes a pair of lateral projections <NUM> and a middle projection <NUM> extending from the main body <NUM>. The middle projection <NUM> and each of the lateral projections <NUM> define a top recess <NUM> between them.

The present disclosure relates to the hammer <NUM> with the valve assembly <NUM> that is externally mounted on the power cell <NUM>. The hammer includes the housing <NUM> that defines the cutout <NUM>. The cutout <NUM> may allow the power cell <NUM> to be easily inserted into or removed from the housing <NUM>. The power cell <NUM> may have to be removed from the housing <NUM> for servicing and/or replacement.

The valve assembly <NUM> may slide into the cutout <NUM> upon insertion of the power cell <NUM> into the housing <NUM>. In order to remove the power cell <NUM> from the housing <NUM>, the mounting bracket <NUM> may have to be disconnected and removed from the top flange <NUM> of the housing <NUM>. The top buffer <NUM> which freely rests on the top surface <NUM> of the power cell <NUM> may be easily removed without using any tools. The power cell <NUM> including the valve assembly <NUM> may be then slidably removed from the housing <NUM>. After removal of the mounting bracket <NUM>, the power cell <NUM> may therefore be removed from the housing <NUM> without requiring the disconnection of additional parts using tools. This may reduce downtime and requirement of tools to service and/or replace the power cell <NUM>.

The wear plates <NUM> may also protect the valve assembly <NUM> from wear and abrasion during operation of the hammer <NUM>. The wear plates <NUM> may be easily attached to or removed from the power cell <NUM>.

Claim 1:
A hydraulic hammer (<NUM>) comprising:
a housing (<NUM>) defining a cutout (<NUM>);
a power cell (<NUM>) slidably received within the housing (<NUM>), the power cell (<NUM>) including a valve assembly (<NUM>) extending from a side (<NUM>) of the power cell (<NUM>), wherein the valve assembly (<NUM>) is at least partially received within the cutout (<NUM>) of the housing (<NUM>); and
a pair of wear plates (<NUM>) at least partially disposed around the valve assembly (<NUM>) of the power cell (<NUM>); characterised in that
each of the pair of wear plates (<NUM>) is coupled to the power cell (<NUM>).