WEAR ASSEMBLY FOR USE ON EARTH WORKING EQUIPMENT
A wear assembly for excavating equipment which includes a wear member and a base each with upper and lower stabilizing surfaces that are offset and at overlapping depths to reduce the overall depth of the assembly while maintaining high strength and a stable coupling. The nose and socket each includes a generally triangular-shaped front stabilizing end to provide a highly stable front connection between the nose and wear member for both vertical and side loading. The lock is movable between hold and release positions to accommodate replacing of the wear member when needed, and secured to the wear member for shipping and storage purposes.
The present invention pertains to a wear assembly for securing a wear member to excavating equipment.
BACKGROUND OF THE INVENTIONWear parts are commonly attached to excavating equipment, such as excavating buckets or cutterheads, to protect the equipment from wear and to enhance the digging operation. The wear parts may include excavating teeth, shrouds, etc. Such wear parts typically include a base, a wear member, and a lock to releasably hold the wear member to the base.
In regard to excavating teeth, the base includes a forwardly projecting nose for supporting the wear member. The base may be formed as an integral part of the digging edge or may be formed as one or more adapters that are fixed to the digging edge by welding or mechanical attachment. The wear member is a point which fits over the nose. The point narrows to a front digging edge for penetrating and breaking up the ground. The assembled nose and point cooperatively define an opening into which the lock is received to releasably hold the point to the nose.
Such wear members are commonly subjected to harsh conditions and heavy loading. Accordingly, the wear members wear out over a period of time and need to be replaced. Many designs have been developed in an effort to enhance the strength, stability, durability, penetration, safety, and/or ease of replacement of such wear members with varying degrees of success.
SUMMARY OF THE INVENTIONThe present invention pertains to an improved wear assembly for securing wear members to excavating equipment for enhanced stability, strength, durability, penetration, safety, and ease of replacement.
In one aspect of the invention, the nose and socket are each provided with offset upper and lower stabilizing surfaces to provide a stable but streamlined design that provides higher strength, better penetration, and an improved flow of material into the excavator as compared to conventional teeth.
In another aspect of the invention, front and rear stabilizing surfaces of the nose and socket are each inclined to resist loads on the wear member with vertical components (herein called vertical loads) and side components (herein called side loads). In addition, shifting loads can be better resisted by such inclined surfaces with less relative motion between the nose and the socket for greater stability and less wear. In one preferred construction, the nose and socket have V-shaped rear stabilizing surfaces and inverted V-shaped front stabilizing surfaces.
In one other aspect of the invention, stabilizing shoulders formed integrally with the body of the wear member bear against complementary supports on the nose to increase stability and strength of the assembly. The shoulders are substantially parallel to the longitudinal axis of the nose to form a highly stable formation that resists vertically applied loads on the wear member. Unlike ears that project rearward from the body of the wear member, the shoulders are backed by the body of the wear member for additional strength. The use of shoulders also requires less metal than ears.
In another aspect of the invention, the nose and socket each includes a first faceted shape at the front end that transitions into a second increased-faceted shape and preferably, also into a third increased-faceted shape at the rear ends. In one preferred example, the front ends of the nose and socket are each formed generally as a triangle that transitions into a hexagonal shape, which, in turn, transitions into an octagonal shape at the rear end. The use of such shape changing formations enables the use of a slender wear assembly for good penetration while maintaining high strength characteristics and side stability.
In another aspect of the invention, the body of the nose and complementary main portion of the socket each includes upper and lower portions. Each of the upper and lower portions have a central facet and a pair of side facets that each extend out an inclination to the corresponding central facets. To achieve the desired stabilization, strength and slimmer profile, the upper and lower portions are asymmetrical such that the upper central facet has an expanding width in a rearward direction, wherein the lower central facet has a narrowing width in a rearward direction.
In another aspect of the invention, the front ends of the nose and socket are each formed with sidewalls that are inclined inward in the upward direction to minimize the lateral projection of the upper corners. The use of such inclined sidewalls at the front ends reduces the outer profile of the assembly for better penetration of the ground. By moving the upper corners inward, the risk of break through (i.e., the formation of holes passing into the socket) is also reduced, thus, lengthening the useable life of the wear member. The use of inclined stabilizing surfaces along the sidewalls further reduces wear as vertical and side loads are both resisted by the same surfaces.
In one preferred embodiment, the nose and socket each includes a generally triangular-shaped front stabilizing end. In one example, the triangular stabilizing end is formed by a generally horizontal lower surface and an inverted V-shaped upper surface. As discussed above, this construction enhances penetration, increases the useable life of the wear member by minimizing the risk of break-through and resists both side and vertical loads with the same surfaces.
In a further aspect of the invention, the nose includes an upper converging wall and a lower converging wall to have the common wedge shape as a compromise of strength and penetration. However, as opposed to prior constructions, the upper wall continues converging toward the lower wall through the front end for enhanced penetration while continuing to provide the desired stabilization.
In one other aspect of the invention, the lock is integrally secured to the wear member for shipping and storage as a single integral component. The lock is maintained within the lock opening irrespective of the insertion of the nose into the cavity, which results in less shipping costs, reduced storage needs, and less inventory concerns.
In another aspect of the invention, the lock is releasably securable in the lock opening in the wear member in both hold and release positions to reduce the risk of dropping or losing the lock during installation. Such an assembly involves fewer independent components and an easier installation procedure.
In a further aspect of the invention, the lock and wear member can be maintained as a single integral component through shipping, storage, installation and use through an easily movable system without reliance on threaded members. This arrangement enables improved part management and easier installation of the wear member with less risk of losing the lock.
In another aspect of the invention, the lock is swung about an axis that extends generally longitudinally for easy use and stability. In the hold position, the lock fits within a cavity defined in a sidewall of the nose, which avoids the conventional through-hole and provides increased nose strength. Moreover, the sides of the lock form a secure and stable locking arrangement without substantial loading of the hinge or latch portions of the lock. In addition, the lock is operable without a hammer for ease of use and enhanced safety.
In another aspect of the invention, the lock is formed with a pivot support and a biasing member to permit not only pivotal movement of the lock between hold and release positions, but also a shifting movement to permit latching in the hold position and/or release positions. In one preferred embodiment of the invention, the lock body defines at least one pry slot whereby a pry tool can securely engage the lock to shift and pivot the lock for easy installation and removal.
In another aspect of the invention, the lock is provided with a latch formation which includes a centrally positional formation to be used to release the lock from the lock position.
The present invention pertains to a wear assembly 10 for releasably attaching a wear member 12 to excavating equipment (not shown). In this application, wear member 12 is described in terms of a point for an excavating tooth that is attached to a lip of an excavating bucket. However, the wear member could be in the form of other kinds of wear parts (e.g., shrouds) or attached to other excavating equipment (e.g., dredge cutterheads). Moreover, relative terms such as forward, rearward, up, down, horizontal or vertical are used for convenience of explanation with reference to the orientation of the assembly in
In one embodiment (
Nose 14 includes a body 18 and a front end 20 (
It is common in digging operations for the teeth to be forced forward and upward through the ground. As a result, the primary directions in which excavating teeth are commonly loaded are rearward and downward. Front face 27 of nose 14 abuts front surface 29 in socket 16 to primarily resist rearward loads. Upper stabilizing surfaces 24 are substantially parallel to axis 26 to provide stable resistance to downwardly applied vertical loads on the front end of wear member 12. Also, due to irregularities in the ground, rocks, and other impediments, the teeth also tend to experience side loads as well as loads that shift. Upper stabilizing surfaces 24 are inclined to resist both downward vertical loads and side loads. Loads that shift between vertical and side loads are also better resisted by the same upper surfaces 24 to reduce shifting of wear member 12 on nose 14, and thereby reduce wearing of the components. The larger surface area provided by both angled upper surfaces 24 as compared to lower surface 22 can also provide a benefit in resisting the expected larger downward loads.
Since vertical loading is typically greater than side loading, upper surfaces 24 are preferably more horizontal than vertical, i.e., at an angle θ between 0 and 45 degrees relative to lower surface 22, and most preferably at an angle θ of about 40 degrees (
A triangularly-shaped front end (along with other parts of the nose) also ensures that wear member 12 will be mounted properly on the nose, i.e., the wear member cannot be mounted the wrong way on the nose. Moreover, since the wear member is not subject to reversible mounting, the nose and socket can be formed to optimize shape for a given application. As example, the nose may be formed with a profile for greater penetration, a shape that reduces the rate of wear on the wear member, and an efficient construction to specially suit loads and wear patterns expected in the desired digging operations.
In an effort to stabilize the mounting of the wear member, it has been known to form the front end of the nose and socket as mating parallelepipeds with rectangular shaped stabilizing surfaces. At times, the wear member can thin causing high stress which may lead to failure or wear through the wear member to expose the nose at the corners, which in either case results in the wear member needing to be replaced before the bit portion 28 has worn away. Since downward loading is typically greater than upward loading and with the flow of earthen material into the bucket, such break through usually occurs along the top of the wear member. With an upward-pointing, triangularly-shaped front stabilizing end for nose 14, upper surfaces 24 are inclined downwardly, in a lateral direction, to shift the upper front corners of the stabilization end to a central position (
While front stabilizing end 20 preferably has a triangular shape formed by upper and lower surfaces 22, 24, other configurations with inclined side surfaces can be used to reduce the lateral projection of the upper front corners. In such a construction, the inclined sidewalls may define a generally trapezoidal shape. As another example, the upper corners may be chamfered to shift the upper corners inward. The chamfers may be made so as to eliminate the sidewalls and/or top walls or to connect the side and top walls. In another example, although planar surfaces are preferred, the inclined surfaces may be curved to define, for example, a generally hemispherically shaped front end.
Moreover, a triangular shaped front end 20 or other front end shapes with inclined sidewalls could be used in connection with other known nose configurations. As an example only, such a front end could be used as a stabilizing front end instead of the stabilizing front end disclosed on the nose in U.S. Pat. No. 5,709,043. In addition, the front end could be reversed for digging operations where the loads and wear would be expected to be along the bottom side as opposed to the top side of the wear assembly.
Nose 14 is further defined in part by an upper wall 31 and a lower wall 33 (
As discussed above, upper wall 31 and a lower wall 33 that are each inclined to diverge away from axis 26 in a rearward direction. To reduce obstructions and enhance flow of earthen material into the bucket, upper wall 31 has a more shallow inclination relative to axis 26 than lower wall 33. Further, nose 14 transitions rearwardly from a relatively small sized front end 20 with facets 22, 24 for high penetration and stability into a larger sized rear end with increased facets for strength and support (
In a preferred construction, nose 14 transitions from a three or four-faceted surface at the front end (depending on whether central facet 34 maintains a significant width in front end 20) into a six-faceted surface into body 18 for strength, stability and a slimmer profile. Body 18 preferably comprises an upper central facet 34 and a pair of inclined side facets 36, and a lower central facet 38 and inclined side facets 40 to present a strong profile. The use of central facets 34, 38 reduces the overall depth of the assembly to provide a more slender projection for better penetration. The top central facet 34 is preferably flat in a transverse direction with a width that expands rearwardly to ease the flow of earthen material into the bucket. The lower central facet 38 is also generally flat in a transverse direction, but preferably has a narrowing width in a rearward direction. This is particularly beneficial on account of the greater inclination of lower side 33 as compared to upper side 31. While planar facets 34, 36, 38, 40 are preferred, curved facets could also be used. Nevertheless, other shapes and arrangements where the nose changes from a relatively small sized front end with a certain facets into a larger sized rear end with increased facets are possible.
Lower side facets 40 are preferably substantially parallel to axis 26 to define rear stabilizing surfaces (
In a preferred embodiment, body 25 transitions into an eight-faceted structure at its rear end 41 (
Base 15 further includes supports 42 adjacent nose 14 for additional stabilization of wear member 12 under upwardly directed loads (
Wear member 12 includes a bit 28 with a front digging edge 44 and a mounting end 46 with a rearwardly-opening socket 16 (
Mounting end 46 further includes shoulders 72 formed by an offset portion 74 of upper side 58 that overhangs past the rear end of lower side 60 (
While any portion of the nose may at times bear loads from the wear member, stabilizing surfaces 22, 24, 40, 42, 52, 54, 70, 72 are intended to be the primary surfaces for resisting vertical and side loads that are applied to the wear member. When loads having vertical components are applied along the digging edge 44 of wear member 12, the wear member is urged to roll forward off the nose. For example, when a downward load L1 is applied to the top of digging edge 44 (
The engagement of stabilizing surfaces 40, 70 provides more stable support for the point as compared to the use of conventional converging surfaces, with less reliance on the lock. For instance, if load L1 is applied to a tooth with a nose and socket defined by converging top and bottom walls without stabilizing surfaces 40, 70, the urge to roll the wear member off the nose is resisted in part by the abutting of converging walls at the rear ends of the nose and socket. Since these converging walls are axially inclined to the longitudinal axis, their abutment with each other urges the point in a forward direction, which must be resisted by the lock. Accordingly, in such known constructions, a larger lock is needed to hold the point to the nose. A larger lock, in turn, requires larger openings in the nose and point, thus, reducing the overall strength of the assembly. In the present invention, stabilizing surfaces 40, 70 (in conjunction with stabilizing surfaces 24, 54) are substantially parallel to longitudinal axis 26 to minimize forward urging of wear member 12. As a result, the wear member is stably supported on the nose to increase the strength and stability of the assembly, reduce wear, and enable the use of smaller locks.
Stabilizing surfaces 22, 42, 52, 72 function in essentially the same manner for upwardly-directed vertical loads. An upwardly directed load L2 (
As noted above, in the illustrated embodiment, stabilizing surfaces 24, 40, 54, 70 are inclined in transverse directions. Preferably, these angled stabilizing surfaces are symmetrical, although an asymmetrical arrangement is possible. The transverse inclination of stabilizing surfaces 24, 40, 54, 70 enables them to resist side loads, such as load L3 (
It is advantageous for the same surfaces to resist both vertical and side loading. Loads are commonly applied in shifting directions as the bucket or other excavator is forced through the ground. With the laterally inclined surfaces, the bearing engagement continues between the same surfaces even if a load shifts, for example, from more of a vertical load to more of a side load. With this arrangement, movement of the point and wearing of the components can be reduced. Stabilizing surfaces 22, 42, 52, 72 are not inclined in the preferred embodiment because the bulk of the loads are expected to be rearward and downward, and the use of horizontal stabilizing surfaces in this direction enables the design of an assembly with less depth.
Stabilizing surfaces 22, 24, 40, 42, 52, 54, 70, 72 are preferably planar, but could have different shapes. For example, the stabilizing surfaces could be formed with broad convex or concave curves. In addition, rear stabilizing surfaces 40, 70 are generally most effective when located at or near the rear end of the nose and socket. Hence, in the illustrated embodiment, the front portions of stabilizing surfaces 40, 70 taper to a front point. Of course, the front portions could have other narrowing shapes, non-converging shapes, or be eliminated entirely. Further, bearing may occur on only one portion of any or all of the stabilizing surfaces.
In one construction, lock 17 fits into an opening in the form of through-hole 81 defined in wear member 12 and a pocket or cavity 83 defined in one side of nose 14 (
Through-hole 81 preferably extends through a side facet 66 (
Lock 17 (
In the illustrated embodiment, lock 17 is composed of a body 110, a resilient member 112 and a shield 114 all bonded or otherwise secured together. Body 110 defines latch formation 115 that engages end wall 87 and stop 95. Shield 114 overlies resilient member 112 to engage bulb 93. Resilient member 112 provides lock 17 with a resilient compressibility.
Cavity 83 in nose 14 is preferably defined by base walls 129, 131 collectively having a generally L-shaped configuration, a front wall 133, and a rear wall 135 (
Lock 17 fits into through-hole 81 such that pivot member 113 bears against bulb 93 for pivotal movement of the lock between the hold position and the release position (
In the hold position, front face 107 of lock 17 opposes front wall 133 of cavity 83, and rear face 108 of lock 17 opposes rear wall 91 of through-hole 81. In this way, wear member 12 is securely held to base 15. In the illustrated embodiment, latch formation 115 includes fingers 116 that set behind facet 66 to prevent release of the lock from the assembly; resilient member 112 biases finger 116 behind facet 66 after insertion of lock 17 (although lock 17 is preferably not tight against end wall 87). In this position, the outer face 123 of lock 17 is generally aligned with or slightly recessed relative to the outer surface 125 of wear member 12 (
Lock 17 further includes a recess 120 along wide end 105. Notch 120 receives stop 95 to hold lock 17 in its release position (
As noted above, lock 17 is placed in the hold position to secure wear member 12 to base 15. Lock 17 is preferably shipped and/or stored in combination with wear member 12 in the release position without base 15. Lock 17 could be structured to store and/or ship in the hold position or some rearward position if desired. Lock 17 preferably includes abutments 128 that prevent lock 17 from falling through through-hole 81 and into socket 16 when nose 14 is absent.
Lock 17 further includes notches 122, 124, 126 which are provided to aid removal of lock 17 from the assembly (
In one construction, front and rear faces 107, 109 of lock 17 are generally parallel to the opposed front and rear walls 133, 135 of pocket 83. In this way, a firm engagement can be had between the lock and the pocket. Nevertheless, in an alternative construction, faces 107 and 109 of lock 17 converge toward inner side 149 to engage similarly converging walls 133, 135 of pocket 83. In this way, the lock can be more easily inserted and removed from pocket 83 as the walls do not engage until fully positioned.
In an alternative embodiment, wear assembly 210 is shown as a tooth for a ripper machine (
In assembly 210, lock 217 includes a wedge 230 and a spool 231 such as disclosed in U.S. Pat. No. 7,174,661, herein incorporated by reference. Wedge 230 has a conical shape and a thread formation in the form of a helical groove 234 (
Hole 283 extends horizontally through a mid-section of nose 214 to receive lock 217 (
In use, wear member 212 is placed over nose 214 so that through-holes 281 generally align with hole 283 to collectively define opening 285. Lock 217 is placed into opening 285 with the arms 236 abutting against rear ends 290 of through-holes 281 and wedge 230 being loosely received into trough 240. Wedge 230 is rotated such that the receipt of ridges 242 in helical groove 234 pulls the wedge farther into opening 285 until the lock has firmly secured wear member 212 to base 215.
The above-discussions concern the preferred embodiments of the present invention. Various other embodiments may be used or other changes made without departing from the spirit and broader aspects of the invention as defined in the claims.
Claims
1-41. (canceled)
42. A wear assembly for excavating equipment comprising:
- a wear member including an exterior surface, a front end facing generally in the direction of travel during excavating, a rear mounting end including a cavity having opposing upper and lower walls, sidewalls extending between the upper and lower walls along the length of the cavity, and a front wall extending between the upper and lower walls at a front end of the cavity, the cavity opening rearward to receive a base of the excavating equipment between the upper and lower walls and between the sidewalls for supporting the wear member on the excavating equipment, and a through-hole extending from the exterior surface to the cavity and opening in one of the sidewalls; and
- a lock secured to the wear member in the through-hole, the lock being adjustable between a hold position and a release position where the lock in the hold position holds the wear member to the base and in the release position permits installation of the wear member onto the base, and the lock being secured to the wear member in both the hold position and the release position irrespective of the insertion of the base into the cavity or the orientation of the wear member to form a single integral component with less risk the lock will be separate from the wear member and lost.
43. A wear assembly in accordance with claim 42 wherein the lock is includes a tool-receiving formation to receive a tool to adjust the lock between the hold position and the release position without the use of threads and without the use of a hammer.
44. A wear assembly in accordance with claim 43 wherein the lock includes a latch to retain the lock in each of the hold and release positions with each said position being in a pre-established location.
45. A wear assembly in accordance with claim 44 wherein the lock includes a body to interact with the base in the hold position to hold the wear member to the base when installed and to permit installation of the wear member on the base in the release position, and a resilient member to resist adjustment of the lock between the hold and release positions.
46. A wear assembly in accordance with claim 42 wherein the lock includes a tool-receiving formation operable to receive a tool to adjust the lock between the hold position and the release position without a hammer.
47. A wear assembly in accordance with claim 46 wherein the lock includes a latch to retain the lock in each of the hold and release positions with each said position being in a pre-established location.
48. A wear assembly in accordance with claim 47 wherein the lock includes a body to interact with the base in the hold position to hold the wear member to the base when received in the cavity and to permit installation of the wear member on the base, and a resilient member to resist adjustment of the lock between the hold and release positions.
49. A wear assembly in accordance with claim 48 wherein the body is movable about an axis between the hold and release positions.
50. A wear assembly in accordance with claim 49 wherein the axis extends generally in the same direction the base is received into the cavity.
51. A wear assembly in accordance with claim 42 wherein the lock includes a body to interact with the base in the hold position to hold the wear member to the base when installed and to permit installation of the wear member on the base in the release position, and a resilient member to resist adjustment of the lock between the hold and release positions.
52. A wear assembly in accordance with claim 51 wherein the lock includes a latch to retain the lock in each of the hold and release positions with each said position being in a pre-established location.
53. A wear assembly in accordance with claim 42 wherein the lock includes a latch to retain the lock in each of the hold and release positions with each said position being in a pre-established location.
54. A wear assembly in accordance with claim 42 wherein the lock is integrally secured to the wear member for shipping and storage as a single integral component.
55. A wear assembly in accordance with claim 42 wherein the lock is secured to the wear member such that they are maintained as a single integral component through shipping, storage, installation and use.
56. A wear assembly in accordance with claim 42 wherein the wear member is a point with a front digging edge.
Type: Application
Filed: Mar 6, 2015
Publication Date: Jun 25, 2015
Inventors: Christopher M. Carpenter (Tualatin, OR), Donald M. Conklin (Lake Oswego, OR), James E. Bearden (Beaverton, OR), Severn D. Durand (Portland, OR), Dziugas Radzius (Portland, OR)
Application Number: 14/641,059