Patent Description:
Excavating equipment, such as buckets, shovels, face shovels, excavators, bucket wheel excavators, are commonly equipped with wear members, also called ground engaging tools ('GET'). The wear members, amongst other tasks, sacrificially protect the excavating equipment from the wear and tear caused by operation of the excavating equipment. In use, the wear members are exposed to the wear and tear otherwise experienced by the excavating equipment and must thus by replaced in regular or irregular intervals.

The wear members are typically mounted on a ground engaging surface of the excavating equipment and secured with a retainer. Depending on the type of excavating equipment, the wear member may be mounted on an adapter and secured with a retainer, the adapter in turn being mounted on the ground engaging surface of the excavating equipment and secured with an adapter retainer. In a similar fashion to the wear member, the adapter requires replacement in regular or irregular intervals.

The removal of the wear member and/or the adapter is a dangerous manual process due to the significant weight (often above <NUM>) of these components. Additionally, the adapter and the wear member may be wedged or unintentionally friction welded in contact zones from the forces imparted on the wear member during use. The wear member and the adapter may also be coated in dust, mud, and particulates, requiring a number of blows with a large sledge hammer to loosen up any fines ingress inside the pocket geometry.

While the removal of locking systems, i.e. retainers, is typically harmless, the removal of the tooth or adapter from its mating part is not. Due to these circumstances significant force is often required to remove the adapter and/or the wear member, creating a potentially unsafe work environment. Such a device for removing a wear member is shown in <CIT>.

It is an object of the invention to substantially address one or more of the problems described above, or at least provide a useful alternative to the above mentioned manual removal methods.

In a first aspect, the present invention provides a device for removing a wear member from a ground engaging surface, the device comprising:.

Preferably, when the wear member engaging portion is in the engaged position, the wear member engaging portion engages a recess in the wear member when the wear member extends into the cavity.

Preferably, the movement of the gripper relative to the body between a first position to a second position causes the wear member engaging portion to move between the open position and the engaged position, respectively.

Preferably, the device further includes a second actuator connected between the body and the first actuator to move the gripper between the first position and the second position, and the first actuator is adapted to move the gripper between the second position and a third position, thereby, if the wear member is engaged by the wear member engaging portion, removing the wear member from the ground engaging surface.

Preferably, the second actuator moves the first actuator to move the gripper relative to the body.

Preferably, the bracing member includes a spacer adapted to bear against a side of the ground engage surface.

Preferably, the side is generally perpendicular to the portion.

Preferably, the body further includes a damping member located in the cavity to receive the wear member.

Preferably, the damping member is a resilient member biased towards the gripper.

Preferably, the resilient member is biased towards the gripper by a spring between the resilient member and the body.

Preferably, the spring extends from the resilient member away from the wear member engaging portion towards the body.

Preferably, the device is suspended from a crane, the crane being located on a utility vehicle, the utility vehicle further having a power supply;
wherein the first actuator and/or the second actuator are powered by the power supply.

Preferably, the power supply is a portable hydraulic power supply.

In a second aspect, the present invention provides a method of removing a wear member from a ground engaging surface, the method comprising the steps of:.

Preferably, the method further comprises the step of:
tilting the device such that an opening of the cavity points towards a safe disposal surface.

Preferably, the method further comprises the steps of:.

Preferred embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings:.

<FIG> shows a ground engaging surface, in a preferred embodiment being a bucket lip <NUM> forming part of an excavator (not shown). The bucket lip <NUM> has a plurality of noses <NUM>, each nose <NUM> being equipped with a wear member 26a, 26b, 26c, 26d, 26e, 26f located along the bucket lip <NUM>. However, it would be appreciated that the wear member <NUM> may, for example, form part of a wheel loader, back hoe style excavator, rope shovel, dragline bucket or similar earth moving equipment instead.

Each wear member <NUM> may include a tooth <NUM> and an adapter <NUM>, or a single piece tooth <NUM>. The term wear member <NUM> throughout the specification may refer to the tooth <NUM>, the adapter <NUM>, a combination of the tooth <NUM> and the adapter <NUM>, or a single piece tooth <NUM>. Each tooth <NUM> is releasably connected to the corresponding adapter <NUM> with a tooth retainer <NUM>. Each adapter <NUM>, or single piece tooth <NUM>, is releasably connected to the corresponding nose <NUM> with a retainer <NUM>.

A further wear member, in this embodiment a number of shrouds <NUM>, is located along the bucket lip <NUM>, between the wear members <NUM>.

<FIG> also shows a device <NUM> for removing the wear member <NUM> from the bucket lip <NUM>, in accordance with a preferred embodiment of the invention. As best seen in <FIG>, the device <NUM> includes a body <NUM> having a cavity <NUM> with an opening <NUM>. The device <NUM> also includes a damping portion, in this embodiment a resilient member <NUM> to frictionally engage the wear member <NUM> when it is inserted into the body <NUM>. As best seen in <FIG>, the resilient members <NUM> are biased towards the opening <NUM> by a pair of springs <NUM> for each resilient member <NUM>. In the embodiment shown in <FIG>, the springs <NUM> are mounted between the opening <NUM> and the resilient member <NUM>, so as to act in tension when the wear member <NUM> engages the resilient members <NUM>, as shown in <FIG>. In an alternative and preferred embodiment shown in <FIG>, the springs <NUM> are located between the resilient member <NUM> and a portion of the body <NUM> away from the opening, so as to act in compression when the wear member <NUM> engages the resilient members <NUM>, as shown in <FIG>.

Returning to <FIG>, the body <NUM> also has a guide structure <NUM> movably supporting a gripper <NUM>, so that the gripper <NUM> is movable relative to the body <NUM> along a gripper axis <NUM>.

As shown in <FIG>, the gripper <NUM>, in turn, has a bracing member, in this embodiment a pair of bracing bars <NUM> connected to the gripper by a bracing bar pin <NUM>. The bracing bars <NUM> are movable between a first position, shown in <FIG>, and a second position, shown in <FIG>. The bracing bars <NUM>, in the second position, abut the shrouds <NUM> adjacent the wear member <NUM> to bear against the shroud <NUM> that forms a portion of the ground engaging surface. As best seen in <FIG>, a first actuator <NUM> is pivotally connected, at a proximal end <NUM> to a pivoting linkage <NUM> that is attached to the body <NUM>, and a distal end <NUM>, to the gripper <NUM>. The first actuator <NUM> is movable between a first position, shown in <FIG> and <FIG>, and a second position, shown in <FIG> and <FIG>, thereby moving the gripper <NUM> between a first position and a second position. The first actuator <NUM> is also movable between along a first actuator axis <NUM> between the second position and a third position, shown in <FIG>, thereby moving the gripper <NUM> between the second position and a third position. When moving between the second position and the third position, the first actuator axis <NUM> is generally parallel to the gripper axis <NUM>.

As best seen in <FIG>, the pivoting linkage <NUM> includes a first actuator pin <NUM> located at the proximal end <NUM>. A strut <NUM> is pivotably connected to the first actuator pin <NUM> at a first end, and pivotably connected to a lever arm pin <NUM> on a lever arm <NUM> at a second end. The first actuator pin <NUM> and the lever arm pin <NUM> each have a pin axis 71a, 71b, respectively. The pin axes 71a, 71b are generally parallel to each other and generally perpendicular to the first actuator axis <NUM>.

The clamp <NUM> is mounted on a shaft <NUM>. The shaft <NUM> is pivotable between a first position, shown in <FIG>, and a second position, shown in <FIG>. A second actuator <NUM> is connected, at a first end <NUM>, to the body <NUM> and, at a second end <NUM> to a second lever arm <NUM> that extends from the shaft <NUM>. Thus, a linear force applied by the second actuator <NUM> to the second lever arm <NUM> is able to pivot the shaft <NUM> between the first position and the second position, thereby causing the first actuator <NUM> to move between the first position and the second position.

As shown in <FIG>, the device <NUM> further includes a pair of wear member engaging portions, in this embodiment a pair of arms <NUM>, each mounted on an arm pin <NUM> so as to be pivotable between an open position, to allow movement of the wear member <NUM> into the cavity <NUM> as shown in <FIG>, and an engaged position, shown in <FIG> to engage the wear member <NUM> when the wear member <NUM> is located in the cavity <NUM>, thereby providing a load path from the ground engaging surface to the arm pin <NUM> to the wear member <NUM>. Each arm <NUM> has a curved slot <NUM> that receives a roller <NUM>, the roller <NUM> being mounted on a roller pin <NUM> extending from the body <NUM>. Each curved slot <NUM> is curved, or slanted, such that a distance between the slot <NUM> to the gripper axis <NUM> increases with distance from the body <NUM>. Each slot <NUM> ends in a distal opening <NUM>.

Each arm <NUM> has a gripping portion <NUM> at an end thereof, each gripping portion <NUM> being adapted to engage a recess <NUM>, shown in <FIG>, in the wear member <NUM>.

Returning to <FIG>, the device <NUM> also includes a first sensor <NUM> mounted to the body <NUM>. The first sensor <NUM> is adapted to provide a first signal to a controller (not shown) indicating that the first actuator <NUM> is in the first position by determining a rotational position of a cam <NUM> that is fixed to the shaft <NUM>. The device <NUM> further includes a second sensor <NUM> mounted to the body <NUM>. The second sensor <NUM> is adapted to provide a second signal to the controller indicating that the bracing bars <NUM> are within their operational movement limit, i.e. to indicate when the bracing bars <NUM> are in danger of making contact with the body <NUM>.

In a second embodiment, shown in <FIG>, the device <NUM> includes a spacer <NUM> connected to the bracing bars <NUM> by a spacer pin <NUM>. The spacer <NUM> is adapted to bear against a side <NUM> of the bucket lip <NUM>, or a shroud <NUM> attached to the side <NUM>, when the bracing bars <NUM> are in the second position. The side <NUM> is generally perpendicular to the portions of the bucket lip <NUM> that are covered by the shrouds <NUM>.

The device <NUM> may be suspended from a portable crane (not shown), or similar manipulator, the crane being located on a utility vehicle (not shown), the utility vehicle further having a power supply (not shown) including a hydraulic, pneumatic, and/or electric supply. The first actuator <NUM> and/or the second actuator <NUM> are powered by the power supply.

Use of the device <NUM> will now be discussed.

To remove a wear member <NUM> from a nose <NUM>, the tooth retainer <NUM> may optionally be removed from the wear member <NUM>. However, preferably, the wear member <NUM> may be removed wholly. A user of the device <NUM> ensures that the first actuator <NUM> is in the first position, and that the arms <NUM> are in the open position, by moving the second actuator <NUM> to the first position. The user also removes the retainer <NUM>.

The device <NUM> is then positioned in general alignment with the wear member <NUM>, as shown in <FIG>, suspended using a first shackle <NUM> and a second shackle <NUM>. The device <NUM> is subsequently moved towards the wear member <NUM> so that the wear member <NUM> abuts the resilient member <NUM>, as shown in <FIG> and <FIG>, the resilient member <NUM> aiding to absorb the impact and to center the wear member <NUM> within the cavity <NUM>. The second actuator <NUM> is then activated so that the shaft <NUM> is pivoted from the first position to the second position, thereby moving the first actuator <NUM> from the first position to the second position, as shown in <FIG>. The movement of the first actuator <NUM> from the first position to the second position translates the gripper <NUM> relative to the guide structure <NUM> along the gripper axis <NUM>, as seen in <FIG>. The roller <NUM> mounted to the gripper <NUM> moves along the curved slot <NUM> as the gripper <NUM> is translated along the gripper axis towards the bucket lip <NUM>, thereby urging the arms <NUM> from the open position to the engaged position so that the gripping portions <NUM> engage the recesses <NUM> of the wear member <NUM>, as shown in <FIG>.

Once the gripping portions <NUM> have engaged the recesses <NUM>, the first actuator <NUM> is activated so that it moves from the second position towards the third position, thereby moving the bracing bars <NUM> from the first position to the second position, as shown in <FIG>. The movement of the gripper <NUM> moves the roller <NUM> through the distal opening <NUM> and out of the curved slot <NUM>.

The movement of the first actuator <NUM> is resisted by the bucket lip <NUM>, or the shroud <NUM> secured to the bucket lip <NUM>, when the bracing bars <NUM> abut the bucket lip <NUM>, or the shroud <NUM> secured to the bucket lip <NUM>, as shown in <FIG>. In the second embodiment, shown in <FIG>, the movement of the first actuator <NUM> is resisted, at one end, by the bucket lip <NUM>, or the shroud <NUM> secured to the bucket lip20. At another end, the movement of the first actuator <NUM> is resisted by the side <NUM> when the spacer <NUM> abuts the side <NUM>.

When the movement of the first actuator <NUM> is resisted, the arms <NUM> transfer the expansive force generated by the first actuator <NUM> to the recesses <NUM> of the wear member <NUM>, thereby urging the wear member <NUM> away from the nose <NUM>, as shown in <FIG>.

When the first actuator <NUM> has moved to the third position, thus being fully expanded, the wear member <NUM> is fully removed from the nose <NUM>. The device <NUM>, carrying the wear member <NUM> with the resilient members <NUM> within the cavity <NUM> and the gripping portions <NUM> in the recesses <NUM>, is then moved away from the nose <NUM>, as shown in <FIG>. The device <NUM> is subsequently tilted so that the opening <NUM> of the cavity <NUM> points towards a safe disposal surface (not shown), such as the ground, as shown in <FIG>. The tilting of the device <NUM> is achieved by suspending the device <NUM> using only the second shackle <NUM> that is rearward of the gravitational center of the device <NUM> and disconnecting the first shackle <NUM>.

The first actuator <NUM> is then activated again to move from the third position to the second position, as shown in <FIG>. As the gripper <NUM> moves along the gripper axis <NUM>, the roller <NUM> is received within the curved slot <NUM> by moving through the distal opening <NUM>. The second actuator <NUM> is then activated to move the shaft <NUM> from the second position to the first position, thereby moving the first actuator <NUM> from the second position to the first position, as shown in <FIG>.

The movement of the first actuator <NUM> from the second position to the first position moves the gripper <NUM> along the gripper axis <NUM>, thereby moving the roller <NUM> along the curved slot <NUM>. The movement of the roller <NUM> along the curved slot <NUM> moves the arms <NUM> from the engaged position to the open position, removing the gripping portions <NUM> from the recesses <NUM>.

The wear member <NUM> may have fallen from the cavity <NUM> to the safe disposal surface, or the wear member <NUM> may still be weakly retained in the cavity <NUM> by the resilient members <NUM>, requiring negligible manual intervention to remove the wear member <NUM> from the cavity <NUM>. The device <NUM> is then tilted to the state shown in <FIG> and is ready to remove a further wear member <NUM>. Tilting of the device <NUM> back to this state is achieved by reconnecting the first shackle <NUM>, in addition to the second shackle <NUM> to revert the device <NUM> to the state shown in <FIG>.

Advantages of the device <NUM> will now be discussed.

The device <NUM> removes, or at least reduces, the requirement for hammers or percussion tools for the removal of the wear member <NUM> from the nose <NUM> by providing the expansive force between the bucket lip <NUM> and the wear member <NUM>.

The device <NUM> reduces the amount of human interaction involved with the removal of a wear member <NUM>. The device <NUM> is positioned and the second actuator <NUM> is activated by the operator. Once the arms <NUM> are engaged with the wear member <NUM>, the operator can move to within a safe working distance and activates the first actuator <NUM>. A remote control (not shown) is used for activating the actuator <NUM> at the safe working distance. The use of the device <NUM> ensures that the risk to the operator during the removal process of the wear member <NUM> is significantly reduced. The device <NUM> may also be adapted to remove the wear member <NUM> from the bucket lip <NUM> "autonomously", i.e. with no direct human interaction with the wear member <NUM>.

The bias of the resilient member <NUM> accommodates a variety of geometries and thus allows the tooth <NUM> alone, or the adapter <NUM> and the tooth <NUM>, or single-piece tooth <NUM>, to be received in the cavity <NUM>. Thus, the device <NUM> is able to remove the tooth <NUM> alone, or the adapter <NUM> and the tooth <NUM> together or a single piece tooth.

The control of the first and second actuator <NUM>, <NUM> with the controller allows the implementation of safety protocols that prevent the arms <NUM> from unintentionally moving from the engaged position, thereby preventing the wear member <NUM> from inadvertently dislodging from within the cavity <NUM>.

The positioning of the springs <NUM> away from the opening <NUM> protects the springs from crushing and decreases frictional wear.

The user of the spacer <NUM> allows the removal of wear members <NUM> located at the edge of the bucket lip <NUM>.

The use of the device <NUM> with existing cranes, or similar equipment, and the provision of pneumatic, hydraulic, and/or electric power from existing cranes, allows retro-fitting of the device <NUM> on existing equipment.

Claim 1:
A device (<NUM>) for removing a wear member (<NUM>) from a ground engaging surface (<NUM>), the device (<NUM>) comprising:
a body (<NUM>) having a cavity (<NUM>) and a wear member engaging portion (<NUM>) to engage the wear member (<NUM>) when the wear member (<NUM>) extends into the cavity (<NUM>);
a gripper (<NUM>) movable relative to the body (<NUM>), the gripper (<NUM>) having a bracing member (<NUM>) adapted to bear against a portion of the ground engaging surface (<NUM>) to thereby provide a load path from the ground engaging surface (<NUM>) to the wear member engaging portion (<NUM>); and
a first actuator (<NUM>) connected to the gripper (<NUM>) and the body (<NUM>), to apply a force to the gripper (<NUM>), to urge the gripper (<NUM>) to move relative to the body (<NUM>), such that, when the bracing member (<NUM>) bears against the ground engaging surface (<NUM>), movement of the gripper (<NUM>) relative to the body (<NUM>) removes the wear member (<NUM>) from the ground engaging surface (<NUM>); characterized in that the wear member engaging portion (<NUM>) is moveable between: an open position to allow movement of the wear member (<NUM>) into the cavity (<NUM>), and an engaged position to engage the wear member (<NUM>) when the wear member (<NUM>) extends into the cavity (<NUM>).