This application is a §371 National Stage Application of PCT International Application No. PCT/IB2013/001897 filed Sep. 4, 2013 claiming priority of AU Application No. 2012903830, filed Sep. 4, 2012 and 2013901940 filed Apr. 29, 2013.
The present invention relates to mechanical connection of wear parts to underlying structures. The present invention has been created in relation to the connection of ground engaging tools to buckets of earth-moving equipment.
Ground engaging tools (GET), for earth-moving equipment, such as those used in mining operations, operate in a highly abrasive environment, are subjected to high impact forces and therefore wear out or become damaged through use. GET, such as teeth used on the front lip or edges of a bucket of the earth moving equipment, therefore require regular replacement.
Traditionally, GET are welded onto the lips of buckets. When the GET come to the end of their useful life, they can be cut from the bucket, and new GET welded in their place.
It will be appreciated that such cutting and re-welding operations are complex, time-consuming and relatively expensive. Further, they must generally be done in a workshop to ensure the cutting off and welding is done correctly, requiring the bucket to be transported away from the earth-moving equipment.
Various mechanical attachment methods have been proposed in an attempt to alleviate these problems. Many of the methods involve the use of bolts and similar fastening devices, inserted within the lip of the bucket. In general, such devices have proved to be of limited use. The insertion of a bolt or similar within a bucket lip can lead to undesirable stress concentrations within the lip, resulting in cracking of the bucket lip. Even where this is avoided, the large forces to which GET are exposed have a tendency to deform connecting bolts, thus making difficult their subsequent extraction using mechanical tools. Indeed, in some cases the deformation can be so severe that the GET must be cut away, completely negating any advantage of mechanical connection.
In response to these issues, the applicant has devised a number of mechanical connection means which overcome these problems. Examples of the applicant's devices are detailed in U.S. Pat. No. 7,219,454 and in U.S. Pat. No. 7,472,503 and in U.S. patent application Ser. No. 13/133,213 (also published as International PCT publication number WO 2010/065990), the contents of all of which are included herein by reference.
These connection means involve the use of a shroud which mounts about a lug or boss on the lip of an excavator bucket; a locking device which locates between the shroud and the boss; and the application of an external compressing force to maintain the relative position of the shroud, locking device and boss.
Although these connection means have proved far less susceptible to deformation than previous mechanical connectors, there have nonetheless been occasions where the connection means have had one or more problems. Sometimes failure of the GET or connection means can occur when the GET is in use due to a load being applied which is higher than the means can bear. The number of individual components forming the connection means can make fitting/refitting a GET time consuming. Other times, when it is necessary to remove the GET, the connection means is troublesome to undo to release the GET from the bucket, or, even if the connection means is released, the GET does not readily remove from the bucket lip, usually because of dirt and/or deformation of the connection means and/or GET preventing removal.
The present invention seeks to provide a means by which removal and preferably application of the GET to earthmoving equipment can be substantially improved.
In accordance with a first aspect of the present invention there is provided a connection means to releasably attach a ground engaging tool (GET) to earth moving equipment, the connection means having a body, a force applying member and a locking member, the locking member arranged to advance relative to the body for the connection means to retain a GET to the earthmoving equipment and to retract relative to the body when releasing the connection means, the locking member including a first portion arranged to positively engage with a member on the earthmoving equipment when the locking member retracts during connection means release.
A further aspect of the present invention provides a connection means to attach a ground engaging tool (GET) to earthmoving equipment, the connection means including an assembly of a body, a force applying member and a locking member having a first portion, the assembly to be received into a recess in the GET, wherein, in use, application of force by the force applying member causes the force receiving member to advance relative to the body and thereby to engage the device with a portion of the earthmoving equipment to apply forces to the GET and the portion of the earthmoving equipment to connect the GET to the earthmoving equipment, and the locking member including means to apply a release force to the portion of the earthmoving equipment when releasing the connection means.
In accordance with another aspect of the present invention there is provided a unitary connection means to attach a ground engaging tool (GET) to earthmoving equipment, the device having a body, a force applying member and a force receiving member, wherein application of force by the force applying member causes the force receiving member to advance relative to the body and thereby to engage the device with both the GET and a portion of the earthmoving equipment to retain the GET on the earthmoving equipment
Thus, beneficially, the connection means is able to positively retract to release the GET from locking engagement with the earthmoving equipment. Known means of connecting a GET to, say, a bucket of earthmoving equipment can use a bolt type mechanical attachment mechanism, but when it comes time to release that mechanism for removal and replacement of the GET, the bolt may undo with difficulty, but the attachment mechanism doesn't retract whatever locking means is used in order to positively release the attachment mechanism to allow removal of the GET. Friction, dirt or corrosion within the mechanism can cause the attachment mechanism not to allow retraction.
The force receiving member may incorporate or be the locking member. The portion of the earthmoving equipment may include an adapter, lug or boss (hereinafter these are collectively referred to as a boss for ease of understanding) on or adjacent a lip of a bucket of the earthmoving equipment.
In use, according to one or more embodiments, an application of force by the force applying member to the locking member causes the locking member to extend from a first side of the body.
The first portion of the locking member may be provided by a channel or groove in the locking member, which may create a projection (or lip) on the locking member.
The locking member projection may engage during release of the connection means with a corresponding portion on a boss attached to the earthmoving equipment. The boss portion may be a projection extending from the boss or a face of the boss.
The locking member may include a stop means arranged to restrict or prevent rotation of the locking member during locking and/or release of the connection means. The stop means may be provided by one or more stop projections from the locking member that engages with the body to prevent rotation of the locking member relative to the body. The stop means may include a pin or key projecting from the locking member.
The force applying member may include a threaded member, such as a bolt. The locking member may include a corresponding threaded member for threading engagement with the thread of the threaded force applying member. The locking member may include a nut, which may be cylindrical externally and threaded internally. However, other forms are considered to fall within the scope of this application, such as quadrilateral, hexagonal or octagonal prism locking member (which may not therefore require the stop means.) Thus, the locking member may advance by rotation of the threaded force applying member.
The force applying member may include a stop means, which may include a shoulder or collar. The shoulder or collar may be provided along a portion of a shaft of the force applying member. This force applying member stop means may engage with a body stop portion. This body stop means may be integral to the body or may be an additional attached or fitted stop means, such as an insert, a press or interference fit key or a grub screw or woodruff key, that projects to act as a stop for the force applying member. Preferably the body stop means may include an insert into an aperture through the body, the insert projecting into a path of travel of part of the force applying means to thereby stop further travel of the force applying means in that direction.
In accordance with a third aspect of the present invention there is provided a ground engaging tool (GET) attachment system for connecting a GET to a bucket lip, the bucket lip having a boss thereon, the GET having a recess which receives the boss in use, a connection means being disposed, in use, between the boss and the GET, the connection means having a body, a force applying member and locking member including a connection means release portion, wherein application of force by the force applying member causes the locking member to travel relative to the body and to engage with the boss, and when releasing the connection means, the locking member reverses its travel and the connection means release portion applies a force to assist in releasing the GET from locking engagement with the bucket lip.
Preferably, the force applying member is slidably received in the body. The force applying member may include a portion that projects through an aperture of the body when received therein. That projecting portion may include a drive head with means to receive a driver to operate the connection means. The drive head may include an external hexagonal head or an internal socket, such as a hex drive socket for a pneumatically operated driver (e.g. a rattle gun).
It is preferred that the force applying member is substantially axially aligned with the force receiving member or locking member.
The force receiving member and/or force applying member may include a piston, and may be substantially cylindrical in shape. In a preferred embodiment, the force receiving member or locking member has a bevelled outer edge of a leading part thereof. This allows a small degree of plastic deformation of the force receiving member/locking member to occur without significantly affecting operation of the connection means.
The force receiving member/locking member may have a hardness less than 90% of the hardness of the force applying member. It is preferred that the ratio of hardness of the force receiving member to the force applying member be between 0.7 and 0.9. Testing has suggested that a hardness ratio of about 0.8 provides an efficacious result.
One or more resilient members may be provided between part of the force applying member and the body and/or between part of the force applying member and part of the force receiving member/locking member. The resilient member(s) may include Belville washers or Nordlock washers, which may have one or more inter-engaging surfaces to prevent or restrict counter-rotation of the force applying member or locking member dependent upon where the resilient members are sited within the connection means body.
The connection means may be provided as a ‘cassette’ or ‘cartridge’ in the sense that the connection means can be provided as a single preassembled device prior to mounting into a recess into the GET. The body can form an external housing for the force applying member and locking member, and the entire connection means device then be inserted as a cassette or cartridge into the recess within the GET mounted loosely on the bucket lip. The force applying member can then be actuated to tighten the GET to the lip and thereby lock the GET in place.
At least one spacer may be provided between the body and a part of the GET. The spacer may be inserted into the recess in the GET before or after the connection means is inserted therein. The connection means may be provided as an assembly of components, which may be provided, preassembled for ready placement into the recess in the GET, or may be assembled on site at the time of mounting the GET to the bucket lip and then inserted into the recess. The spacer may include a plate, preferably with an aperture therethrough. The head of the force applying member may project into or through the aperture in the spacer when assembled in place with the GET. This can allow access to the drive means on the force applying member, such as by a pneumatically actuated driver e.g. a ‘rattle gun’, to tighten and release the connection means.
The body may include a recessed end to allow the first portion of the locking member with the channel or recess to project from an end of the body to engage with the boss at least when releasing the connection means. The recess may be a step or opening in an end of the body.
The connection means may include a force application portion arranged to apply a release force to the GET when operating, preferably when un-tightening, the connection means.
The force applying portion may be provided by an projection on the body of the connection means.
Another form of the present invention provides a method of releasing a ground engaging tool (GET) from earthmoving equipment, the method including releasing a connection means releasably attaching the GET to the earthmoving equipment, during the releasing the connection means positively retracting together a locking member and body to contract the connection means.
The locking member may apply a force to a portion of the earthmoving equipment during the retraction. The force may be applied to a boss on a lip of a bucket of the earthmoving equipment.
During un-tightening of the connection means, the connection means may apply a removal force to the GET.
A further aspect of the present invention provides a mount for a ground engaging tool (GET) to a bucket of earthmoving equipment, the bucket including a chamfered edge, the chamfer including a surface with a boss or lug thereon, the boss or lug arranged to receive the GET and have the GET retained thereon by a connection means, the boss or lug being predominantly on the surface of the chamfer.
Preferably the boss or lug is welded to or integrally cast with the bucket lip.
The chamfer may be provided at an angle of 10° to 20°, preferably around 15° such that the surface of the chamfer for the boss or lug extends between 150 mm and 250 mm, preferably around 200-220 mm., back from a leading edge of the lip. Thus, the boss or lug can be predominantly on the chamfered surface without needing to extend onto the flat surface of the bucket. This helps reduce the height profile of the boss or lug, and therefore allows for a lower profile GET as well as enhances a straight line offering of the GET onto the boss or lug.
A further aspect of the present invention provides a method of releasing a connection means prior to removing a ground engaging tool (GET) from earthmoving equipment, the connection means including a force applying member, a locking member and a body, the method including:
releasing the force applying member from a force applied state to a force relieved state and at least partially retracting the locking member,
removing a spacer from between the connection means and the GET,
moving the body to at least partially occupy space created by said removal of the spacer,
at least partially inserting a release member into a space created between the body and the GET by said moving the body at least partially into the spacer space,
actuating the force applying member to at least partially retract the locking member into the body and, by relative movement of the locking member with respect to the body, cause the body to apply pressure via the release member to the GET to assist in releasing the GET from the earthmoving equipment.
Thus, advantageously, the connection means can be used to help remove or loosen the GET which can, after prolonged work use, become wedged onto the lip of the earthmoving equipment, such as by fines of material filling crevices in and around the get or by distortion of the material of the GET, the boss or the lip of the earthmoving equipment.
Furthermore, actuating the force applying member can allow the locking member, which is engaged with a portion of the boss, to retract into the body, such that the locking member and body move relative to one another. Because the locking member is engaged with the boss, the body moves forward to apply pressure to the release member inserted between the body and the rear face of the opening in the GET ahead of the body. This allows the body to ‘push’ the GET off the boss because the locking member e.g. the piston within a pin-block, is hooked over a lip on the boss.
Further, the reaction force of the body pushing on the GET may allow the locking member to release from engagement with a member on the earthmoving equipment and to at least partially retract the locking member into the body, thereby releasing the connection means for removal from within the GET opening. Thus, a method is provided that positively releases the connection means.
Preferably the release member includes a spacer used to the rear of the connection means. The spacer may have an aperture or recess therethrough which allows an actuation tool to be inserted through the spacer to operatively engage with the force applying member. The recess may be in the form of a ‘cut-out’ in the sense of a hole that opens out to a periphery of the spacer. The spacer may therefore also be used as the release member for insertion between the body and the GET to assist in removing the GET from the earthmoving equipment.
The recess in the spacer may include a central hole therethrough and an opening to the periphery that is wider than the central hole and connects to the central hole and opens to the periphery of the spacer. The wider portion at the periphery may allow the spacer to span over the locking member when the spacer is inserted ahead of the body between the body and the GET.
Preferably, the body of the connection means includes at least one projection on both sides of an upper surface of the main portion of the body, and adjacent the opening in the body where the locking member projects from. Such projections increase the frontal surface area of the body, particularly the surface area that the spacer will contact when inserted to release the GET.
The projections adjacent the frontal surface of the body may have sloping or bevelled rearward surfaces which aid in removing debris from the cavity behind projections to help move or release the body.
The force applying member may be retained in the body by a resilient retaining means, such as a circlip around a shaft portion of the force applying member. A shoulder of the force applying member at least as wide as the diameter of the resilient retaining means may contact the resilient retaining means to prevent the force applying member from withdrawal or removal from the body until the resilient retaining means is released, such as by use of a release tool.
Preferably the body has an upper surface that is externally exposed in the opening of the GET. Thus, effectively, the upper surface of the body forms part of a surface for material to flow over when the GET is in use, rather than the body being mostly or completely inserted into and protected by the GET. This allows for a reduced profile GET, which reduces material and manufacturing cost as well as smoothing the flow of material over the GET when the GET is in use.
It will be convenient to further describe the invention with reference to preferred embodiments of the present invention. Other embodiments are possible, and consequently, the particularity of the following discussion is not to be understood as superseding the generality of the preceding description of the invention. In the drawings:
A bucket 10 of an earthmoving vehicle (not shown) has a front lip 12 with several bosses 14 (also known as lugs or adapters), each to receive a ground engaging tool. The front lip tapers from a thicker rear portion adjacent the bowl 16 of the bucket to a thinner front edge 18. Each boss fits onto the lip and extends over the front edge. Each boss is welded in place.
For assembly of the connection means, with the O-ring and stop pin in place on the piston, the piston is initially threaded onto the bolt. The bolt is inserted head 52 first into the body with the resilient means around the head. The key 48 is inserted into an aperture under the body which prevents the bolt coming back out of the body and acts as a stop for the bolt when releasing the connection means to remove a GET. More on that later. The body has an aperture 54 giving access to the head of the bolt. In fact, it is preferred that the head of the bolt projects out of the aperture for ease of access to connect a drive means to the head of the bolt to tighten or loosen the connection means. The shoulder or collar 56 on the bolt abuts the resilient means which is therefore trapped between the interior surface of the body adjacent the aperture 54 and the collar/shoulder 56.
A spacer 58, in use, sits adjacent the rear face 60 of the body and has a spacer aperture 62 that aligns in use with the aperture 54 of the body.
By rotating the bolt to un-tighten the connection means (when the GET is to be removed), the piston contacts the lip of the boss, which retracts the bolt and piston together. The shoulder or collar on the bolt contacts the key projecting within the body which results in the body being drawn towards the piston. This action allows the connection means to contact and thereby be loosened within the recess or opening of the GET for removal therefrom.
When un-tightening (releasing), the shoulder or collar 56 on the bolt 36, which has a flat face 86 on one side and a tapered face 88 on the other, advances because of its threaded connection to the nut (piston). The tapered face contacts the key 48 which prevents further advancement of the bolt and causes the body to move forwards due to the nut (piston) being in engagement with the boss during this loosening. The connection means therefore positively contracts.
When the connection means is tightened as shown in
It will be appreciated that, when un-tightening the connection means, a projection on the body 94 can push against a portion 96 of the GET to help move the GET forwards and thereby assist with removal of the GET from the bucket lip.
The bucket lip preferably has a bevelled or chamfered face between 110 mm and 130 mm, more preferably around 120 mm. This gives a larger surface area on the bucket lip to receive the boss and allows the boss to be mounted giving a lower profile on the bucket lip. This allows the GET to have a lower profile and therefore reduces the amount of material in the GET. This also facilitates straight, single movement installation and removal of the GET.
An alternative embodiment of a connection means 110 and GET 112 is shown in
Adjacent and to the rear of the opening 114, the GET 112 includes a spacer opening 116 to receive the spacer 118 to the rear of the connection means.
It is noticeable that the body 120 of the connection means will have an exposed upper surface 122 when mounted into the opening 114 of the GET. This differs from the shielded upper surface for the connection means body in the previously described embodiments, thereby confirming the lower profile of the GET and entire assembly.
The connection means 110 includes the body 120 with an aperture 124 to receive a bolt 126. The bolt is retained inside the body by a resilient retainer 128, such as a circlip. A piston 130 threadingly engages with the bolt. The piston has a projection 132 that prevents the piston rotating when the bolt is rotated. Thus, the threaded relationship between the bolt and piston causes the piston to advance or retract relative to the body when the bolt is axially rotated clockwise or counter-clockwise.
The body 122 includes projections 134, (136 not shown) toward the lower rear of respective side surfaces 138, (140 not shown) thereof.
The leading end 142 of the body includes projections above the aperture to receive the bolt and piston. The projections help shield the piston from damage when the GET is in use and provide additional material to strength the front end of the body. The projections 144,146 include bevelled surfaces 148,150 which provide a leverage surface for a tool to pry the connection means loose if required
The lower rear projections 134,136 are guided in corresponding slots or channels in the opening of the GET. Those slots or channels can also be provided as part of the opening 116 for the spacer 118, preferably with forward leading channel or slot portions from a lower end thereof to allow the body to slide forwards and lock into place once inserted into the opening.
As shown in
As shown in
The head end portion 168 of the piston presses against the rear contact face 174 of the boss. The rear portion of the piston includes an annular recess 164 which retains a resilient seal 166 for the piston in the body opening.
The projection 132 is received into a groove 147 in the internal surface of the opening into the body, and prevents the piston rotating when advanced by rotation of the bolt.
As shown in
As seen in
Number | Date | Country | Kind |
---|---|---|---|
2012903830 | Sep 2012 | AU | national |
2013901490 | Apr 2013 | AU | national |
Filing Document | Filing Date | Country | Kind |
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PCT/IB2013/001897 | 9/4/2013 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2014/037780 | 3/13/2014 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
3371437 | Wilson | Mar 1968 | A |
5713145 | Ruvang | Feb 1998 | A |
6729052 | Ollinger, IV | May 2004 | B2 |
7219454 | Maher | May 2007 | B2 |
Number | Date | Country |
---|---|---|
2003204374 | May 2002 | AU |
0902132 | Mar 1999 | EP |
Number | Date | Country | |
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20150211214 A1 | Jul 2015 | US |