HK1088371B - Wear assembly and wear member - Google Patents

Description

Wear-resistant assembly and wear-resistant component

This application is a divisional application of application No. 02813657.8 entitled "wear assembly" filed on 7/3/2002.

Technical Field

The present invention relates to a wear assembly, and more particularly to a wear assembly for mining, excavating and earth moving equipment. The inventive design is particularly well suited for use not only with excavating teeth, but also for supporting other wear members.

Background

In the mining and construction industries, wear members are often provided on the digging edge of the equipment to protect the bucket and the like and/or to engage and break up the ground to be collected. Wear parts are therefore required to work in severe wear situations and are subject to considerable wear. Thus, the wear parts must be replaced periodically.

To minimize the loss of material from replacement of old components, wear assemblies are often made as two or more detachable components including a joint and a wear member. The adapter is attached to the excavator edge by welding, mechanical attachment, or casting along the excavator edge to provide a forwardly extending projection for supporting the wear member. The wear member has a socket located above the projection for receiving the wear member and a forwardly facing working end. At the point, the working end is typically a narrow digging edge. The wear member completely encases the joint protrusion, thereby helping to protect the protrusion from damage. For example, depending on a number of factors, generally between approximately 5 and 20 prongs may be installed in succession on a single fitting before the fitting is damaged and needs to be replaced. To facilitate replacement of the wear member in the field, the wear member is typically secured to the nose of the adapter by a removable lock, such as a lock pin.

Wear assemblies used in mining, excavation and construction, particularly excavating tooth systems, are subjected to large and variable forces applied in various directions. Accordingly, the prongs and other wear members must be securely fastened to the fitting to withstand axial, vertical, reverse, and lateral loads as well as impact, vibration, and other types of forces. Vertical loading has been particularly troublesome because the large moment it generates "rotates" the wear member up the joint, sometimes causing the wear member to come out. The adapter nose provides support for the wear member and the lock in most cases plays a great role in gripping the point and resisting loads, especially moments and counter forces.

In a conventional tooth system 1 (fig. 22), the adapter nose 2 and the mating socket 3 in the point 4 are wedge-shaped and include converging top and bottom surfaces 2a, 2b, 3a, 3 b. A central load P directed downwards is applied at the free end 4a of the tip 4, which will create a moment such that the tip 4 tries to rotate on the projection 2. The load P is generally transmitted to and resisted by the upper side of the top 2c of the projection (reaction force a) which contacts the front end 3a of the socket 3, and the lower side of the bottom 2d of the projection (reaction force B) which contacts the bottom or rear end 4d of the prong 4. These reaction forces generate a reaction moment to resist the moment created by the force P. It will be appreciated that a large vertical force can produce a very large pull-out moment. In addition, the presence of shock, vibration, abrasion, and dust increases the difficulty of resisting the large removal forces.

In the embodiment of a downward center load P, the vertical component of the reaction force A is generally equal to the downward load P plus the vertical component of the reaction force B, however, due to the presence of the nose converging wall, the horizontal component of each reaction force A and B is directed forward, which pushes the point off the nose.

In addition, in such conventional teeth, the locking pin is typically hammered into place and held firmly by friction, which is primarily caused by the apertures disposed in the point and the apertures in the adapter nose. However, wear of the point and the adapter will cause the connection to loosen and increase the risk of loss of the locking pin. Thus, the locking pin is often initially placed very securely within the defined opening to delay the onset of the over-slackening condition. Thus, the lock pin must be repeatedly hammered into and out of the opening with a sledgehammer. This can be a cumbersome and time consuming task, especially for larger sized teeth.

Currently, a tightening elastomer is often placed in front of the lock pin to maintain a tight fit between the point and the fitting as wear begins to occur. Although the elastomer acts to pull the prongs onto the adapter, it also reduces the resistance of the locking element to the application of torque and opposing forces. These loads place stresses on the elastomer beyond what it can withstand. Thus, during use, the elastomer over-works causing it to fail prematurely and the locking pin to be lost, which in turn causes the prong to be lost.

Loss of the point due to pin failure, loosening or elastomer problems not only results in premature loss of the point and wear of the adapter nose, but may also result in damage to the machine that may be handling the excavated material, especially in mining operations. In addition, since the joints are often secured by welding, replacing the joints often results in considerable downtime of the excavating equipment.

Various prong and projection designs have been developed to increase the stability of the prong-to-adapter engagement, reduce the ejection force of the prong, and reduce the load on the locking element.

In the version of the tooth 1 ' (fig. 23), the front end of the projection 2 ' and the socket 3 ' are each provided with a square configuration with upper and lower stabilizing flats 5 ', 6 '. Due to the provision of the stabilizing plane 5 ', the downward central load P' on the free end 4c 'of the prong 4' will be transmitted to the nose tip 2a ', thereby generating a vertical reaction force a' that normally does not generate a large horizontal component force pulling the prong out of the nose. Nevertheless, the reaction force B' will still generate a large horizontal component forward at the rear of the nib, which pushes the nib out of the protrusion. This design improves the stability of the prong over conventional tooth systems, yet applies a greater removal force and may apply a greater shear force on the locking member.

In another version, such as disclosed in U.S. patent No.5,709,043 to Jonse et al, the nose and socket are provided with a square front end and a rear bearing surface that is substantially parallel to the longitudinal axis of the tine. In this configuration, the combined action of the front stabilising plane and the parallel bearing surface causes a reaction force, generally only vertical, to be generated at the ends and bottom of the projections. These vertical reaction forces generally do not produce a large horizontal component. Thus, this configuration greatly reduces the force with which the prongs are pushed out of the adapter. This steady state of the tip also reduces movement and movement of the tip over the fitting to reduce wear. However, many other factors (e.g., impact, etc.) and opposing forces still create a large shear force on the locking element.

In other versions, such as in U.S. Pat. No.4,353,532 to Hahn, the point and adapter are each provided with a helical turn or thread so that the point will rotate about its longitudinal axis when mounted on the adapter nose. Due to the arrangement of the thread, the point rotates about the longitudinal axis of the tooth as soon as the ejection force is generated, and normally presses the locking element against the adapter nose. These stresses are different from the higher shear forces applied to conventional teeth, but the lock is less likely to fail. While this configuration has the advantages of higher strength and retention, the configuration of the tab and socket is complex and costly to manufacture.

Disclosure of Invention

The present invention relates to a wear assembly that provides a stable engagement that is able to withstand heavy loads without placing undue stress on the lock.

In a preferred construction, the bearing surfaces are oriented to direct a horizontal component of the generated force against, for example, a centrally vertical load, rearwardly to more firmly urge the wear member to the joint nose.

In another embodiment of the invention, the wear member rotates the joint about its longitudinal axis from time to better resist removal forces. In a preferred embodiment, this rotational movement is generally achieved by a linear tongue and groove that is simple and inexpensive to manufacture. The interfitting rails and grooves allow the wear assembly to be more slender in shape than other embodiments that may have helical threads for better penetration and less metal material in excavation applications. Such grooves and rails also avoid the high stresses caused by the use of relatively sharp grooves to form helical threads.

In another embodiment of the invention, the joint protrusion or socket of the wear member is formed by rails that disengage from each other when extended rearwardly. Thus, the mating projections or sockets have grooves that matingly receive the rails. In a preferred embodiment, the vertical divergence of the rails prevents axial securement of the wear member and allows the wear member to twist as it moves toward or away from the joint nose.

In another embodiment of the invention, the joint has two bearing surfaces located on opposite sides of the longitudinal axis and oriented in opposite directions. In a preferred embodiment, these bearing surfaces reduce the wear of the terminal fibers on the top and bottom of the protrusions. In addition, the bearing surface preferably forms part of the raised rail on the joint to form a generally Z-shaped cross-section.

In another embodiment of the invention, the joint protrusion or socket of the wear member widens as it extends forward. In a preferred embodiment, the adapter and socket include mating rails and grooves that diverge to allow the wear member to twist during installation. The structure has sufficient clearance to receive the widened nose portion of the nose portion in the socket to better resist removal of the wear member.

In another embodiment of the invention, the locking element is tapered to fit into an interfitting channel to reduce friction and ease insertion or removal of the locking element. In this arrangement, the entire length of the locking element does not frictionally slide along the aligned openings, but rather engages the sides of the recess at or near the engagement location. Thereby eliminating the need to hammer the lock as it is inserted or removed. In a preferred embodiment, the locking member has a locking element that secures the locking member within the channel to prevent unwanted loss or disengagement.

The above and other objects, features and advantages of the present invention will be further described by the following detailed description of the invention with reference to the accompanying drawings.

Brief description of the drawings

FIG. 1 is a perspective view of an excavating tooth system of the present invention;

FIG. 2 is an exploded perspective view of the tooth assembly;

FIG. 3 is a front view of a tooth assembly adapter;

FIG. 4 is a front view of a joint protrusion having only a front bearing surface parallel to the plane of the view;

FIG. 5 is a rear perspective view of a tip of a tooth forming apparatus;

FIG. 6 is a rear view of the tip;

FIG. 7 is a partial top view of the tooth forming apparatus;

FIG. 8 is a cross-sectional view of the tooth assembly taken along line 8-8 of FIG. 7;

FIG. 9 is a side view of the point to be loaded into the nose of the adapter;

FIG. 10 is a partial cross-sectional view of a point with a fitting installed;

FIG. 11 is a force vector diagram of the tooth system according to FIGS. 1 and 2;

FIG. 12 is a perspective view of an alternative embodiment of the tooth system of the present invention;

FIG. 13 is a force vector diagram of the tooth system according to FIG. 12;

FIG. 14 is a side view of a coupling of another alternative embodiment of the tooth system of the present invention;

FIG. 15 is an exploded perspective view of a second tooth system with a selective lock of the present invention;

FIG. 16 is a partial side view of the second tooth system with the alternative lock in the locked condition;

FIG. 17 is a partial cross-sectional view taken along line 17-17 of FIG. 16;

FIG. 18 is a perspective view of the alternative locking element;

FIG. 19 is a rear view of the alternative lock engaging the point of an alternative tooth system;

FIG. 20 is a side view of another alternative lock for insertion into a tooth system;

FIG. 20a is a perspective view of the locking element shown in FIG. 20;

FIG. 20b is a side view of the locking element shown in FIG. 20;

FIG. 21 is a side view of another alternative lock for insertion into a tooth system;

FIG. 21a is a perspective view of the locking element shown in FIG. 21;

FIG. 21b is a perspective view of the locking member shown in FIG. 20 with the elastomeric bottom and pawl shown in cross-section;

FIG. 22 is a force vector diagram of a conventional tooth forming apparatus;

FIG. 23 is a force vector diagram of another known tooth forming device;

Detailed Description

The present invention relates to a wear assembly for protecting a wear surface. In particular, the wear assembly is particularly useful in the fields of excavation, mining, construction, and the like. The wear assembly is well suited for use in forming an excavating tooth system, but may be used to form other wear members.

For purposes of example, the present invention will be described herein in terms of an excavating tooth system. Other wear parts (e.g., shrouds) manufacture will use the same nose and socket arrangement, but may have different working and mounting ends. For descriptive purposes only, the present description uses terms such as upper, lower, vertical, etc., which should be understood to be associated with the orientation of the tooth system of fig. 1. The use of these terms does not indicate that the wear assembly is to be used in this particular orientation. The wear assembly may be oriented differently than shown in fig. 1.

In a preferred construction, the tooth system 1 includes a point 12, a coupling 14, and a locking member 16 (FIGS. 1-10). The joint 14 preferably has a forwardly projecting tab 18 and a mounting end 21 in the form of a pair of rearwardly extending legs 22 (fig. 1, 2 and 9-10). The legs 22 are adapted to straddle the digging edge 23 of the excavator and be welded in place. The mounting end may be connected to the adapter in other different ways, such as by mechanical connectors or integrally molded with the digging edge. In addition, particularly in large form relieved teeth, the adapter may be connected to a second adapter or the like, which in turn is fastened to the digging edge.

The projection is generally wedge-shaped and is formed by converging walls 24, 26, side walls 28, 30 and a front bearing surface 32. The bearing surface 32 is adapted to bear axial loads exerted on the wear member 12. The converging walls 24, 26 are preferably formed with a gentle transverse curve for added strength and durability (fig. 3 and 8), although they could be flat, curved with greater curvature, or surfaces of another configuration. The sidewalls 28, 30 extend in generally parallel planes, although preferably with a slight taper. However, the sidewalls may be of a highly inclined configuration if desired. The transition edges between the converging and side walls are typically rounded to minimize stress concentrations at these locations.

The side walls 28, 30 of the nose 18 are each formed with a shoulder 34 and a rail 35 (fig. 2, 3, 4 and 9) having an outer surface 36 and a side surface 37. in a preferred construction, the rails 35 diverge from one another as they extend rearwardly in generally parallel planes (i.e., the side walls extend rearwardly). in particular, one rail 35a extends rearwardly from the support surface 32 in a direction generally parallel to the rearward extension of the converging wall 26, while a rail 35b extends rearwardly from the support surface 32 in a direction generally parallel to the converging wall 24. in this manner, the rails 35a and 35b diverge in a generally vertical direction as they extend rearwardly.

In a preferred construction, each rail is adjacent to and extends substantially parallel to each converging wall 24, 26. Thus, the outer edge of each converging wall 24, 26 defines the top or bottom of the adjacent rail, while the side 37 extends generally parallel to the rearward extension of the converging wall. However, other variations are possible. For example, the sides may be non-linear in shape or extend in a direction that is not parallel to the converging walls. Additionally, the rails may be spaced from the converging walls so that they may have a second side (not shown) away from the converging walls 24, 26.

The outer surface 36 of each rail 35 is substantially vertical. Preferably, the side surfaces 37 and the side flaps 34 are arranged diagonally to form a generally V-shaped groove 40 (FIGS. 3 and 8). Thus, the side surfaces 37 and the side wings 34 each have a surface area that is transverse to the vertical direction to form a first bearing surface for bearing vertical and lateral loads exerted on the prongs 12. The converging walls 24, 26 form a second bearing surface that can contact the socket under heavy loading or after wear of the components. Each side 37 is preferably disposed at an angle of 75 deg. to 115 deg., most preferably 95 deg., relative to the respective flap 34. However, other angles may be used. The side flaps 34 are generally triangular in shape so that they can expand as they extend rearwardly to form progressively larger portions of each side wall 28, 30.

Tip 12 is in the shape of a generally wedge-shaped structure defined by converging walls 43, 45 and sidewalls 47, 49 (fig. 1-10). Converging walls 43, 45 are tapered to form a forwardly projecting digging edge 51, and a rearwardly opening socket 53 is provided to receive the nipple projection 18.

The socket 53 is preferably shaped to closely receive the joint protrusion 18 (fig. 5, 6 and 8). Thus, the socket is defined by converging surfaces 55, 57, side surfaces 59, 61 and a front surface 63. Each side surface 59, 61 is formed with a groove 65 and an inwardly projecting ridge or protrusion 67. The groove 65 has a shape to accommodate the rail 35 on the tab of the connector. Thus, in a preferred construction, the recess 65 preferably has a shape that extends along the opposing converging surfaces 55, 57. The projections 67 each define a side surface 69 and an inner surface 71, the side surface 69 and the inner surface 71 being opposite and supporting the side surface 37 and the shoulder 34, respectively. Thus, the side surfaces 69 and the inner surface 71 form a first bearing surface for supporting a generally vertically applied load, while the converging surfaces 55, 57 form a second bearing surface that may contact the nose under heavy loads or after wear of the parts. The front surface 63 is adapted to abut the bearing surface 32 during axial loading.

While the projection is preferably provided on the adapter and the socket in the point to minimize the amount of metal required for the wear member, a rearwardly extending projection may be provided on the point which will be received in a socket defined in the adapter. Also, the configuration of the socket and the protrusion may be reversed so that an inner rail (not shown) may be provided in the socket and a mating groove may be provided on the protrusion (not shown).

Because the rails 35 diverge from the grooves 65, the prongs 12 must be twisted or rotated when mounted on the adapter nose 18. in a preferred construction, the prongs are rotated about one-eighth of a turn when mounted, thus, the prongs fit onto the adapter nose in a manner more like the prongs and adapter are formed with helical threads rather than having straight rails and grooves, the prongs 12 are mounted on the nose 18 by first positioning the prongs 12 relative to the nose 18 so that the rear 73 of each groove 65 is positioned adjacent the front 75 of the corresponding rail 35 to receive the rail, as shown in FIG. 9, because the grooves diverge vertically, the front ends of the rails align with the rear ends of the grooves so that the prongs are rotated relative to their final position, thus, when the prongs are slid onto the nose, the prongs rotate generally about the longitudinal axis X to provide sufficient clearance for the rails, eventually allowing the rails 35 to be inserted into the corresponding grooves 65 fig. 10 shows the prongs 12 mounted on the projections 18 with the rails 35 fully inserted into the grooves 65 of the sockets 53.

Thus, the present invention has some of the advantages of previous wear members provided with helical threads (e.g., U.S. Pat. No.4,353,532), but is simpler in shape and less expensive to manufacture. The opposed rails of the present invention are easier to cast than the helical thread means. In addition, using larger rails and grooves instead of the more pointed spiral grooves reduces stress risers on the tabs for increased strength and durability.

The present invention also provides other advantages not available with conventional helical thread devices. The present invention does not use a conical base for the projection, but rather a wedge shape that is more elongated in configuration. Thus, the height of the protrusion (between the top and bottom surfaces) is not limited by the conical base, so the height of the protrusion can be adjusted as desired. Thus, the projections of the present invention may be used to form a tooth system having a more elongated configuration than a configuration having a helical thread. A more slender configuration of the tooth system provides better insertion during digging and requires less metal to manufacture.

Additionally, the degree of twist may be varied by varying the angle defined by the divergence of the rails. Generally, the greater the angle, the greater the amount of twist the tip undergoes during installation and removal.

With this structure, the tip 12 is stably placed on the joint protrusion 18. The vertically centered applied load P1 on the free end 51 of the point 12 produces a lower extraction force (fig. 11) than conventional teeth due to the horizontal component of the reaction forces a1 and B1. For example, a downward central load P1 on the free end 51 of the prong 12 creates reactive forces A1 and B1 at the top and bottom of the projection 18. The vertical component of the reaction force a1 is substantially equal to the vertical component of the load P1 plus the reaction force B1. However, since the ramp prevents the rearward or bottom end of the point from moving upward in the opposite direction to the lower converging wall 45, the horizontal component of the reaction force B1 is directed rearward to push the point onto the fitting rather than pull it out. This securing or tightening force at least partially counteracts the ejection force generated by the horizontal component of reaction force a 1. Loads with vertical force components applied to different parts of the point 12 do not always result in the described fastening force, but this effect will very advantageously occur under normal loading.

In another preferred construction, the front free end 42 of the nose 18a is formed in a generally rectangular configuration having upper and lower stabilizing flats 44, 46 (fig. 12 and 13). These stabilizing planes 44, 46 extend substantially parallel to the longitudinal axis of the tine to provide further support for stabilizing the point to the joint, particularly against vertical loads on the forward end of the point 12 a. The substantially parallel planes of stability may be inclined by up to about 7 degrees relative to the longitudinal axis for pull-pulls. Although the stabilising planes may be inclined to a greater angle, their stabilising effect will decrease with increasing inclination. The socket 53a of the prong 12a has a pair of leading stabilizing flats 78, 79 that engage the stabilizing flats 44, 46 on the adapter nose 18 a. The shape of the front end of the socket is preferably substantially rectangular to fit the front end of the protrusion, although other non-rectangular shapes may be used for the front protrusion and the front end of the socket.

In the preferred tooth system 10a, a downwardly directed center load P2 applied to the free end of the point 12a produces a substantially vertical reaction force A2 that produces substantially no horizontal component as a disengaging force (FIG. 13). As described above, the slope of the rails creates a horizontal component at the bottom of the point with a holding force, rather than a removal force. Thus, by this loading action, the overall effect of the bearing surfaces (i.e., the stabilizing flats and the rails) is to tighten the point onto the adapter rather than to pull it out.

The resultant tightening force will also reduce the movement of the point on the adapter nose, which in turn reduces wear on the tine structure.

In a conventional tooth system (fig. 22), the outer edges of the upper and lower converging walls 2a, 2b (i.e. the surfaces that are vertically furthest from the longitudinal axis) of the nose 2 will have a higher stress value under vertical loads, since these loads have a tendency to bend the nose. In conventional teeth, the outer converging surfaces form the primary bearing surfaces and are subjected to the highest stress levels. As a result, these surfaces move and rub against the socket walls and are subject to high levels of wear under heavy loads. In the present invention, the rails 35 and the flanks 34 form a first bearing surface. Because these bearing surfaces are closer to the central horizontal plane of the tooth system, the bearing surfaces have less of an impact on the ability of the projections to withstand high bending loads than the wear impact of the outer converging walls. The tooth form relieved apparatus of the present invention is a stronger and more durable apparatus due to less wear. Thus, smaller tooth systems that require less metal and are more permeable, manufactured in accordance with the present invention, may replace larger conventional tooth systems. In addition, the reduction in outer edge wear will allow the section modulus to remain constant throughout the life of the tab to maintain the strength of the tab.

As an alternative, the nose front end and corresponding socket may be substantially wider than the nose rear end, due to the rotation required for installation and removal of the tooth system; that is, the side walls may diverge slightly in a wedge shape as they extend forwardly at an angle of up to about 5 °. The increased width of the projection and socket in front of the projection will limit the path of the point out of the projection to within the design rotation even if wear occurs. This configuration therefore increases the resistance to forces, especially counter forces, attempting to remove the tip.

As another alternative, the projection may have a longitudinally extending rail 80, the rail 80 having an outer side surface 81 and a lateral bearing surface 83 (fig. 14). The lateral bearing surfaces 83 are substantially parallel to each other and to the longitudinal axis X of the tooth. In these arrangements, the land depth preferably increases as the land extends behind the land; that is, the converging walls of the projections form the upper or lower surface of each rail 80, even though the lateral bearing surfaces extend rearwardly in a direction generally parallel to the longitudinal axis of the tooth. Nevertheless, the rails may have a constant depth and be spaced apart from the converging walls only. If the rails do not diverge, the prongs are not rotated onto the adapter nose. In this embodiment, without the beneficial feature of rotating the point when it is inserted and removed, the rails still have a stable surface (relative to conventional tooth forming devices) that reduces stress on the outer edges of the converging walls and, as noted above, reduces wear of the bearing surfaces in resisting bending forces. The use of only two rails to form a substantially Z-shaped cross-section improves the load and wear advantages and reduces the amount of material used. This embodiment may also be used when the tip is mounted without or without twisting. As one example, the tines may be welded to a metal plate and the assemblies may then be mounted together on the projecting adapter projections along the digging edge.

For all embodiments, the protrusion and the tip are preferably formed in a symmetrically rotating manner about the longitudinal axis Z, so that the tip can be reversibly mounted on the protrusion. However, the present invention may also use asymmetrical projections and/or prongs.

The pick and adapter assembly of the present invention may use a variety of different locking elements to prevent the pick from being removed from the adapter. Because the lock 16 is subjected to compressive forces at least partially in place of shear forces (and thus experiences reduced shear loads) in resisting dislodging of the tines 12 from the projections 18, the lock need not be as strong as locks used in other conventional tine and connector assemblies that substantially only apply shear loads on the lock. The locking member 16 is preferably disposed along one side of the tab 18 as shown in fig. 1 and 2. However, the locking member may be located at other locations having a vertical or horizontal central passage (as is provided with conventional tooth systems). In addition, virtually any conventional locking member that can secure a point to a fitting, including solid locking pins, pins with tensioned elastomers, or locks with rigid protective sleeves, as disclosed in U.S. Pat. No.5,469,648 to Jones et al, can be used in conjunction with the present invention.

For example, FIG. 2 shows a locking member 16 in the form of a push-in detent received in a vertical channel on the side of the nose, the nib is provided with at least one rearwardly extending lug 91 having an inwardly extending flange 93 to engage the rear side of the detent and retain the nib to the adapter, as is known.

In a preferred construction, the locking pin 16' is provided in the form of a wedge to secure the point to the fitting. Referring particularly to fig. 15-18, a tapered vertical channel 103 is provided along one side projection 18 'to accommodate the wedge lock pin 16'. Although the locking member may be tapered over its entire length, in practice the locking member need only be tapered over a substantial portion of its length. In a preferred construction, the front surface 104 is curved rearwardly along the entire length of the locking element in an arc such that the taper extends substantially along the entire length of the locking element. Fig. 15 shows a blind road which extends only across the partial protrusion and tapers to the closed end 105 of the base. However, if desired, the tapered pin may also employ an open channel that extends entirely through the fitting.

The locking pin 16' has a corresponding shape adapted to the wedge channel 103 (fig. 15-18). The locking pin 16' preferably terminates in a narrow prong 106. The detent 16 ' has a support portion 107 having a front surface 104 for engaging the shoulder 109 of the tab (i.e., the front edge of the channel 103) and a rear surface for engaging the flange 93 ' of the lug 91 '. In the embodiment shown in fig. 15-18, the locking pin 16' has a rearwardly extending web 111 to strengthen the locking pin against axial forces and to ensure proper insertion of the locking pin. However, the locking pin may be consistently round, rectangular, or other desired shape.

The tab 18 'defines a slot 113 that is associated with the channel 103 such that the flange 93' is located along the side of the tab to a position within the channel. The detent 16 'defines a recess 115 behind the rear face 107 and abutting the web 111 to receive a portion of the flange 93'. The latch 16' may be formed by any conventional method, such as casting.

The locking pin 16' is preferably retained within the channel 103 through the use of a locking element. In the embodiment shown in FIGS. 15-18, the locking element is a set screw 121. The channel 103 preferably includes a recess 125 for receiving a set screw to better retain the locking pin within the channel 103, although a recess is not required. Once the locking pin 16' is installed in the channel 103, the set screw 121 is tightened. The set screw 121 may be upset at the end or provided with a retainer ring or other means to prevent the set screw from disengaging the lock pin. The locking pin preferably includes a hanger 123 that protects the set screw from wear. A spring (not shown) may also be attached to the set screw to limit loosening of the set screw during vibration.

The locking pin 16' may also be used in combination with other wear assemblies. For example, as shown in FIG. 19, the locking pin may be used to retain the tip 128 by a simple wedge socket, lug 132, flange 130. The tapered lock pin of the present invention may also be used with a tooth relief assembly (not shown) having a vertical or horizontal central bore.

As an alternative, other locking elements, such as an elastomer-supported detent, may be provided to prevent the detent from being removed from the recess. In addition, while the embodiment of FIGS. 15-18 show the locking element coupling the locking pin to the fitting, the locking element may instead be operable to couple the locking pin to the tip. In addition, the locking element need not be connected to the locking pin, but may be a separate component or attached to the adapter or prong (see, for example, U.S. patent No.4,965,945).

As an alternative embodiment, the latches 131, 133 (FIGS. 20-20 b and 21-21 b) may be wedge-shaped instead of the latch 16'. Latch 131 has a detent 134 biased outwardly at an end 136 by an elastomer 138 to fit under a ledge 140 defined by the adapter nose. The pawl preferably has a protruding contact surface 136a for forming a secure engagement with the projection 140. The detent 134 is preferably bonded to the elastomer 138, which in turn is bonded within the recess of the cast body 135. In the latch 133, the pawl 141 is biased to move along a curved path 143 by an elastomer 145. The free end 147 of the pawl 141 engages a notch 149 or the like defined in the joint projection. In various embodiments, the adapter nose has a narrow slot (not shown) through which a tool can be inserted to push the detent into the elastomer to release the detent 134, 141 when it is desired to remove the lock pin.

One of the advantages of wedge pins is that they are easier to load and unload than conventional push-in latches. The wedge surface allows the locking pin to be inserted without any resistance from the point or protrusion until the locking pin is almost fully inserted into the passage. The wedge-shaped locking pin can be removed with a pry rather than hammering because the locking pin only needs to travel a short distance before being released from the passage. Once released, the latch can be removed by hand. In contrast, with conventional push-in latches, the two bearing surfaces of the latch are nearly parallel to ensure good bearing contact between the prong and the projection. Thus, the push pin is subjected to significant resistance over the entire travel distance as it is inserted into and removed from the wear assembly.

Another advantage of the wedge-shaped locking pin of the present invention is that the force required to remove the locking pin configured to engage the locking element is greater than the force required to remove a conventional push-in locking pin. The wedge-shaped locking pin is prevented from moving downward because the recess is narrow or closed at the end, and a locking element, such as a set screw, prevents the locking pin from moving upward out of the recess. The locking pin relies on mechanical interference rather than a tight fit to prevent the tapered locking pin from being removed once installed.

The above description relates to preferred embodiments of the present invention. Other various embodiments, as well as various changes and alternatives, may be devised without departing from the spirit and broader aspects of the claimed invention.

Claims (11)

1. A wear assembly comprising:

a fitting having a rear mounting end for securing the wear assembly to a wear surface, and a forwardly extending nose having a pair of rails;

a wear member defining a longitudinal axis and having a pair of converging walls extending to a narrow forward working end, a pair of side walls, and a rearwardly opening socket for receiving said nose, said socket having a pair of grooves each on opposite sides of said socket for receiving said rails, wherein each groove diverges from a plane aligned with said longitudinal axis and extending along said narrow forward working end;

wherein the forward free ends of the projections form a structure having upper and lower stabilizing planes that are substantially parallel to the longitudinal axis, the socket having a pair of forward stabilizing planes that engage the upper and lower stabilizing planes on the projections,

and wherein a downwardly directed central load applied to the free end of the wear member generates a substantially vertical reaction force that generates substantially no horizontal component as a release force, and the inclination of the raised rail creates a horizontal component at the bottom end of the wear member with a holding force, rather than a release force; and

a locking member for securing the wear member to the fitting.

2. A wear assembly in accordance with claim 1 in which the nose is generally wedge-shaped and is formed of converging walls, side walls and a front bearing surface, the side walls of the nose each being formed with a shoulder and a rail having an outer surface and a side surface, and in which the socket is shaped to closely receive the nose and is defined by converging surfaces, side surfaces and a front surface, and each side surface of the socket being formed with a recess and an inwardly projecting projection, in which the recess is shaped to receive the rail on the nose, the projections each defining a side surface and an inner surface, the side surfaces and inner surfaces of the projection being opposed to and bearing the side surfaces and shoulder of the rail, respectively.

3. A wear assembly in accordance with claim 1 or 2 in which the socket has a generally Z-shaped cross-sectional configuration along a substantial portion of its length.

4. A wear assembly in accordance with claim 1 in which each of the grooves has a substantially constant width and depth along substantially its entire length.

5. A wear assembly in accordance with claim 1 in which the adapter includes a channel for receiving a lock, and the channel and the lock each narrow along a portion of their lengths.

6. A wear assembly in accordance with claim 5 in which the passage has a closed end and extends only partially through the adapter.

7. A wear assembly in accordance with claim 5 in which the channel and lock taper along substantially their entire length.

8. A wear assembly in accordance with claim 1 in which the adapter has a channel for receiving the lock and the lock has a locking element for securing the lock in the channel.

9. A wear assembly in accordance with claim 8 in which the locking element is a set screw.

10. A wear assembly in accordance with claim 8 in which the locking element is a resiliently biased detent.

11. A wear assembly in accordance with claim 8 in which a pocket is formed in the channel to receive a portion of the locking element.