Position biased locking pin assembly for ground engaging wear members - Patents.com

Abstract

To provide an improved connector structure.SOLUTION: A fixing pin assembly for fixing a wear member to a support structure can have a body part and a shaft member which is partially arranged in the body part and extends from the body part, and the shaft member is rotatable between a first position where removal from the support structure of a ground and engagement member is mechanically prevented, and a second position where removal from the support structure of the ground and engagement member is enabled. The wear member for receiving the fixing pin assembly can have a bore extending laterally through a bore member with a proximal opening and a distal opening, and an inclination part for attachment and an inclination part for removal can be arranged in the proximal opening so as to be engaged with a core part of the shaft member of the fixing pin assembly.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This application claims priority to U.S. Nonprovisional Patent Application No. 16 / 843,623, filed April 8, 2020, and U.S. Provisional Patent Application No. 62 / 834,214, filed April 15, 2019, entitled "Position-Biased Locking Pin Assembly for Ground-Engaging Wear Members," both of which are incorporated herein by reference in their entireties.

[0002] The present disclosure relates generally to a digging tooth assembly including a locking pin assembly for securing components of the digging tooth assembly. More particularly, the present disclosure relates to a digging tooth assembly secured by a releasable locking pin assembly having an improved locking structure with rotational interference to prevent inadvertent unlocking. [Background technology]

[0003] These are often removably carried by a larger underlying structure, such as an excavating bucket, and are subject to abrasive contact with deposited earth or other material. For example, excavating tooth assemblies provided on excavating equipment, such as excavating buckets, typically include a relatively large adapter portion that is suitably secured to an equipment structure, such as the forward bucket lip. The adapter portion typically includes a forwardly protruding nose having a reduced cross-section. Replaceable cutting edges usually include an opening that releasably receives the adapter nose. To retain the cutting edge on the adapter nose, substantially aligned lateral openings are formed in both the cutting edge and the adapter nose, and a suitable connector structure is driven into and forcefully retained within the aligned opening to releasably secure the replaceable cutting edge on its associated adapter nose.

[0004] Material displacement devices, such as excavating buckets found on construction, mining, and other earthmoving equipment, often include replaceable wear parts, such as earth-engaging teeth. Conventional connector structures come in many different types. One type of connector structure typically must be forcefully driven into an aligned cutting edge and adapter nose opening, for example, with a sledgehammer. The inserted connector structure must then be forcefully banged out of the cutting edge and adapter nose openings to allow the worn cutting edge to be removed from the adapter nose and replaced. This conventional need to bang the connector structure into place and then later bang it out can easily pose a safety hazard to personnel performing the installation and removal.

[0005] Various alternatives to pound-in connector structures have previously been proposed for releasably retaining replaceable cutting edges on adapter noses. While these alternative connector structures desirably eliminate the need to smash the connector structure onto and off the adapter nose, they typically present various other types of problems, limitations, and drawbacks, including, but not limited to, complexity of construction and use or undesirably high cost.

[0006] Some types of connector structures are rotatable between locked and unlocked positions. However, continuous vibration, high shock, and repeated loading of the cutting edge can cause the connector structure to inadvertently rotate from the locked position to the unlocked position. This can cause excessive wear at the interface between the connector structure and the cutting edge, affecting the useful life of both the connector structure and the cutting edge.

[0007] Therefore, an improved connector structure is needed. Summary of the Invention

[0008] According to one exemplary aspect, the present disclosure is directed to a position-biased locking pin assembly for securing a ground engaging member having a side opening to a support structure alignable with the side opening.

[0009] In one aspect of the present disclosure, a locking pin assembly for securing a ground engagement member to a support structure includes a body portion, a shaft member, a locking mechanism, a biasing member, and a plunger. The body portion is positioned to selectively non-rotatably protrude into an opening in the support structure and may have an opening formed therein. The shaft member may have a distal end and a proximal end, the distal end having a first locking mechanism and disposed within the body portion. The locking mechanism may include a tang portion extending radially from the proximal portion of the shaft member outside the body portion. The shaft member may be rotatable relative to the body portion between a first position, where the locking mechanism can be positioned to mechanically prevent removal of the locking pin assembly from the ground engagement member when the locking mechanism is positioned to secure the ground engagement member to the support structure, and a second position, where the locking mechanism can be positioned to allow removal of the locking pin assembly from the ground engagement member when the locking mechanism is positioned to secure the ground engagement member to the support structure. The biasing member can be disposed within the body portion. The plunger can be disposed between the biasing member and the distal end of the axial member and can have a second engagement mechanism configured to selectively engage with the first engagement mechanism of the axial member. The biasing member can bias the plunger toward the axial member. The second engagement mechanism can be configured to engage with the first engagement mechanism to provide resistance during rotation of the axial member relative to the plunger in each of two opposing directions.

[0010] In one embodiment, the first and second engagement mechanisms can be configured to rotate relative to one another to rotate the shaft member from one of the first and second positions to the other of the first and second positions when a rotational force applied to the shaft member exceeds a magnitude of resistance to rotation applied by the biasing member. The first and second engagement mechanisms and the biasing member can be configured such that the resistance to rotation applied by the biasing member occurs during a first portion of the rotational movement and does not occur during a second portion of the rotational movement. One of the first and second engagement mechanisms can have two adjacent notches separated by a resistance peak, and the other of the first and second engagement mechanisms can have teeth configured to selectively seat within each of the two notches. The resistance peak can be located approximately midway between the two adjacent notches. The two adjacent notches can be centered approximately 90 degrees apart. The other of the first and second engagement features can have a third notch, and the resistance peak can be sized and shaped to fit within the third notch when the tooth is seated within one of the two adjacent notches. The first engagement feature, the second engagement feature, and the biasing member can be configured to provide tactile feedback to a user confirming rotation of the shaft member between the two adjacent notches to transition from the first position to the second position and from the second position to the first position.

[0011] In some embodiments, the locking pin assembly can have a rotation stop element. The shaft member can have a partially circumferential groove formed therein. The rotation stop element can be configured to mechanically interfere with opposing ends of the groove to limit the range of rotation of the shaft member relative to the body portion. The groove can extend helically such that engagement of the rotation stop element with the groove translates rotation of the shaft member into axial displacement of the shaft member relative to the body portion. The rotation stop element interfering with the end can limit rotation of the shaft member relative to the body portion to a range of approximately 90 degrees. The rotation stop element can be, for example, a dowel extending partially through the body portion.

[0012] In some embodiments, the locking pin assembly can include a second rotational stop element extending from the plunger and configured to prevent rotation of the plunger while allowing axial displacement of the plunger. The second rotational stop element can include a second dowel fixed relative to the body portion. The plunger can have an elongated recess through which the second dowel extends. Alternatively or additionally, the second rotational stop element can include a protrusion extending from the plunger and fixed relative to the plunger. The protrusion can extend into a longitudinal channel formed in an inner wall surface of the body portion.

[0013] In some embodiments, the shaft member and plunger may define a longitudinally extending reference axis. A first cross-section of the body portion perpendicular to the reference axis adjacent the proximal end of the body portion may have a first cross-sectional area, and a second cross-section of the body portion perpendicular to the reference axis adjacent the distal end of the body portion may have a second cross-sectional area smaller than the first cross-sectional area. The body portion may have an engagement surface along only one side parallel to the reference axis. In this regard, the locking pin assembly may be oriented within a bore extending through the ground engagement member into the support structure, and at least a portion of the engagement surface may be configured to engage a load-bearing surface of the support structure defined by an inner wall of the bore. The load-bearing surface may be located on one side of the bore where the locking pin assembly exerts a force in response to a force useful for removing the wear member from the support structure.

[0014] Further, in some embodiments, the body portion can be shaped to be received within a bore extending through the wear member and into the support structure, such that when attached, the locking pin assembly is fixed relative to the wear member but movable relative to the support structure. The body portion can include a head, and the shaft member can extend through the head. The head can have a periphery, a portion of which can have a non-circular shape configured to be received within a correspondingly shaped recess in the wall of the wear member, such that engagement of the head with the wall of the recess prevents rotation of the body portion.

[0015] In some embodiments, a fixation pin assembly for securing a ground engagement member to a support structure can have a body portion, a head, and a tip. The body portion can have an outer surface with a proximal end and a distal end. The head can be disposed at the proximal end and can have a periphery, a portion of the periphery having a non-circular shape configured to be received within a correspondingly shaped proximal recess in the wall of the ground engagement member. The tip can be disposed at the distal end, a portion of the tip having at least one flat side and a non-circular peripheral profile configured to be received within a correspondingly shaped distal recess in a portion of the ground engagement member opposite the first recess. Engagement of the head with the proximal recess and engagement of the tip with the distal recess can prevent rotation of the body portion relative to the ground engagement member.

[0016] The reference axis may extend longitudinally through the body portion. The outer surface may have an engagement surface along one side parallel to the reference axis. At least a portion of the outer surface opposite the engagement surface is non-parallel to the reference axis. For example, the upper, lower, and rear sides of the body portion may be non-parallel to the front side. The locking pin assembly may be configured to be oriented within a bore extending through the ground engagement member into the support structure such that at least a portion of the engagement surface is engageable with a load-bearing surface of the support structure defined by an inner wall of the bore. The load-bearing surface may be located on one side of the bore against which the locking pin assembly exerts a force in response to a force that serves to remove the ground engagement member from the support structure.

[0017] In another aspect of the present disclosure, a wear member for mounting on an adapter carried on a ground engagement device using a locking pin assembly can have an outer surface, an inner surface, a bore, a mounting ramp, and a removal ramp. The inner surface can define a cavity within the wear member. The bore can extend through the wear member from the outer surface of the first wall to the outer surface of a second wall opposite the first wall. The mounting ramp can be disposed adjacent to the bore and configured to engage a first surface of a tang of the locking pin assembly when the locking pin assembly is disposed within the bore when the tang is rotated in a first direction from an unlocked configuration to a locked configuration. The removal ramp can also be disposed adjacent to the bore and configured to engage a second surface of the tang opposite the first surface of the tang when the tang is rotated in a second direction opposite the first direction from the locked configuration to the unlocked configuration. In some embodiments, the mounting ramp and the removal ramp are integral with the first wall. The mounting ramp can be configured to translate rotation of the tang portion in a first direction into axial displacement of the locking pin assembly upon engagement of the mounting ramp with a first surface to facilitate seating of the locking pin assembly within the wear member. Similarly, the removal ramp can be configured to translate rotation of the tang portion in a second direction into axial displacement of the locking pin assembly upon engagement of the removal ramp with a second surface to facilitate removal of the locking pin assembly from the wear member.

[0018] In yet another aspect of the present disclosure, a method for securing or removing a wear member from an adapter carried on a ground engagement device using a locking pin assembly may include a first rotation step of rotating the locking pin assembly in a first direction relative to a body portion of the locking pin assembly while the locking pin assembly is disposed in a bore passing through the wear member and the adapter through a first range of motion (or "portion of motion") in which a first surface of a tooth on a shaft member engages a corresponding first surface of a notch on a plunger disposed in the body portion. The plunger may be substantially rotationally fixed relative to the body portion, and rotation of the shaft member through the first range of motion causes a biasing member to axially displace the plunger from an initial position toward a compressed position. The method may further include a second rotation step of rotating the shaft member in a first direction relative to the body portion through a second range of motion in which a second surface of the tooth slides against a corresponding second surface of the notch. During rotation of the shaft through the second range of motion, the biasing member may return the plunger to the initial position. The first and second rotation stages can move a locking feature of the locking pin assembly, such as a tang extending from the shaft member, from a first configuration to a second configuration, such that when the locking feature is in one of the first and second configurations, the locking feature engages with the wear member or the adapter to prevent withdrawal of the locking pin assembly from the wear member, and when the locking feature is in the other of the first and second configurations, the locking pin assembly is removable from the wear member.

[0019] In some embodiments, the first range of motion comprises a range of 0 degrees to 180 degrees, and the second range of motion comprises a range of 0 degrees to 180 degrees. For example, in some embodiments, one or both of the first range of motion and the second range of motion may have a range between 20 degrees and 160 degrees, between 40 degrees and 140 degrees, between 70 degrees and 100 degrees, etc.

[0020] In a further embodiment, the present disclosure is directed to a locking pin assembly for securing a ground engaging member to a support structure. The locking pin assembly can have a body portion arranged to selectively protrude non-rotatably into an opening in the support structure. The body portion also has an opening formed therein. The shaft member can have a first axis and include a distal end and a proximal portion, the distal end including a first plurality of equidistantly spaced teeth. The first plurality of equidistantly spaced teeth can be radially spaced about the first axis at an angle ranging from approximately 30 degrees to 120 degrees, and the distal end is disposed within the body portion. A tang portion can extend radially from the proximal portion of the shaft member outside the body portion. The shaft member may be rotatable relative to the body member between a first position where the tang portion can be positioned to mechanically prevent removal of the lock pin assembly from the ground engagement member when the tang portion is positioned to secure the ground engagement member to the support structure, and a second position where the tang portion can be positioned to allow removal of the lock pin assembly from the ground engagement member when the tang portion is positioned to secure the ground engagement member to the support structure. A biasing member may be disposed within the body member. A plunger may be disposed between the biasing member and the distal end of the shaft member, the plunger having a second axis and including a second plurality of equidistantly spaced teeth. The second plurality of equidistantly spaced teeth are radially spaced about the second axis in a range of approximately 30 degrees to 120 degrees and are shaped to selectively engage with the first plurality of equidistantly spaced teeth of the shaft member to provide resistance to rotation in two opposing directions. In some embodiments, the first plurality of equidistantly spaced teeth and the second plurality of equidistantly spaced teeth are shaped to provide approximately equal resistance to rotation in two directions.

[0021] In yet another exemplary aspect, the present disclosure is directed to a locking pin assembly for securing a ground engagement member to a support structure. The locking pin assembly can have a body portion with an opening formed therein and can include a shaft member having a first axis and including a distal end and a proximal portion. The distal end can have protruding teeth extending axially and offset from the first axis, and the distal end can be disposed within the body portion. The tang portion can extend radially from the proximal portion of the shaft member outside the body portion. The shaft member can be rotatable relative to the body portion between a first position where the tang portion can be positioned to mechanically prevent removal of the locking pin assembly from the ground engagement member when the tang portion is positioned to secure the ground engagement member to the support structure, and a second position where the tang portion can be positioned to enable removal of the locking pin assembly from the ground engagement member when the tang portion is positioned to secure the ground engagement member to the support structure. A biasing member can be disposed within the body portion. A plunger can be disposed between the biasing member and the distal end of the shaft member. The plunger can have a second axis and can include second teeth extending proximally and offset from the second axis. The second teeth can engage with the first teeth to provide resistance to rotation in two opposing directions. In some embodiments, one of the shaft member and the plunger includes a notch adjacent the respective first or second teeth, and each of the first and second teeth is sized to form a radial arc ranging from about 30 degrees to 120 degrees about the first and second axes, respectively.

[0022] It is to be understood that both the foregoing general description and the following figures and detailed description are exemplary and explanatory in nature and are intended to provide an understanding of the present disclosure without limiting the scope thereof. In that regard, further aspects, features, and advantages of the present disclosure will become apparent to those skilled in the art from the following description.

[0023] The accompanying drawings illustrate examples of the systems, devices and methods disclosed herein and, together with the description, serve to explain the principles of the present disclosure. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is an assembled perspective view of a digging tooth assembly embodying the principles of the present disclosure. [Figure 2] FIG. 2 is an exploded perspective view of the assembly of FIG. [Figure 3A] FIG. 3A is an exploded perspective view of a fixation pin assembly according to the present disclosure. [Figure 3B] FIG. 3B is a diagram showing an example of the tip of the plunger of FIG. 3A. [Figure 3C] FIG. 3C shows an alternative example of the plunger tip. [Figure 4A] FIG. 4A is a top view of the fixation pin assembly of FIG. 3A in an assembled configuration. [Figure 4B] FIG. 4B is a front view of the fixation pin assembly of FIG. 4A. [Figure 4C] FIG. 4C is a cross-sectional view of the fixation pin assembly of FIG. 4A. [Figure 4D] FIG. 4D is a cross-sectional view of an alternative fixation pin assembly having an elongated profile. [Figure 5A] FIG. 5A is a partial side view of the locking pin assembly in the unlocked position. [Figure 5B] FIG. 5B is a partial side view of the locking pin assembly in the locked position. [Figure 6] FIG. 6 is a cross-sectional view showing a rotation stop element interacting with a groove in a shaft member according to the present disclosure. [Figure 7] FIG. 7 is a front cross-sectional view of the assembly of FIG. [Figure 8] FIG. 8 is a top cross-sectional view of the assembly of FIG. [Figure 9] FIG. 9 is a partial left side view of the assembly of FIG. 1 showing the interaction of the locking pin assembly and the wear member. [Figure 10] FIG. 10 is a right side cross-sectional view of the assembly of FIG. 1 showing the interaction of the locking pin assembly and the wear member. [Figure 11] FIG. 11 is a right-side perspective view of a wear member embodying the principles of the present disclosure. [Figure 12] 12 is a partial left perspective view of the wear member of FIG. 11 showing the proximal opening of the bore through the wear member. [Figure 13] FIG. 13 is a perspective view of the proximal opening of FIG. 12 as viewed from inside the cavity of the wear member. [Figure 14] FIG. 14 is a cross-sectional view of the proximal opening of FIG. [Figure 15] 15 is a right-side cross-sectional view through the cavity of the wear member of FIG. 12 showing the proximal opening of FIG. 12. FIG. [Figure 16] FIG. 16 is a flow chart of a method for securing a wear member onto an adapter using a securing pin assembly according to the present disclosure. [Figure 17] FIG. 17 is a flow chart of a method for removing a wear member secured by a securing pin assembly from an adapter. DETAILED DESCRIPTION OF THE INVENTION

[0025] These figures will be better understood with reference to the following detailed description.

[0026] For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language may be used to describe such embodiments. It will nevertheless be understood that no limitation of the scope of the present disclosure is intended. Any changes and further modifications to the described apparatus, devices, methods, and any further applications of the principles of the present disclosure are fully contemplated, as would normally occur to one of ordinary skill in the art to which this disclosure pertains. Moreover, this disclosure may describe some elements or features in detail with respect to one or more embodiments or figures, and those same elements or features may be described without increased detail when they appear in subsequent figures. It is fully contemplated that features, components, and / or steps described with respect to one or more embodiments or figures may be combined with features, components, and / or steps described with respect to other embodiments or figures of the present disclosure. For simplicity, in some instances, the same or similar reference numbers may be used throughout the figures to refer to the same or similar parts.

[0027] The present disclosure relates to an excavating tooth assembly including a locking pin assembly arranged to removably secure an adapter to a wear member, such as a tooth. The locking pin assembly includes a radially extending, rotatable locking element (or "tang") that engages the inner surface of the wear member and mechanically prevents the locking pin assembly from being inadvertently removed. A biasing member creates mechanical interference with rotation of the tang from a locked position to an unlocked position. Resistance to rotation is provided during a first range of motion and no resistance is provided during a second range of motion during rotation of the tang relative to the body of the locking pin assembly from the locked position to the unlocked position and from the unlocked position to the locked position. This feature provides tactile feedback to a user, assuring that the locking pin assembly has been properly transitioned from locked to unlocked or from unlocked to locked. Furthermore, the resistance to rotation can help reduce or minimize the chance of inadvertent rotation.

[0028] Because the locking pin assembly employs mechanical interference to prevent inadvertent rotation of the components of the locking pin assembly, the locking pin assembly can withstand vibration, high shock, and repeated loading while minimizing the chance of inadvertent unlocking. Additionally, some embodiments of the locking pin assembly may be arranged to emit an audible noise, such as a click, when the locking pin assembly achieves a locked state. This may allow a user, such as a machine operator, to install new wear parts and replace old wear parts more easily than is possible with conventional connector pins.

[0029] 1 and 2 illustrate an exemplary embodiment of an assembly according to the present disclosure. In the illustrated embodiment, the digging tooth assembly 100 includes a wear member 104 (or "ground engaging member") in the form of a replaceable cutting edge attached to an adapter 102 (or "support structure") with a securing pin assembly 106. It should be understood that an assembly according to the present disclosure may have any type of ground engaging member and corresponding support structure to which the ground engaging member is secured with a pin. The digging tooth assembly 100 may find particular utility in mobile installation equipment. For example, the digging tooth assembly 100 may be used in construction, mining, excavation, and other industries. The adapter 102 has a forked rear base, which may be bonded (welded) or otherwise secured to, for example, the lip of a bucket. Extending from the rear base is a forwardly protruding nose for receiving the wear member 104. A transverse bore 160 extends through the opposite vertical side of both the wear member and nose portion, and a locking pin assembly 106 may be inserted into the transverse bore 160 to hold the wear member 104 on the adapter 102. It should be noted that the digging tooth assembly 100 may have one or more intermediate adapters, and the locking pin assembly 106 may be inserted to hold the intermediate adapter on the adapter 102 as the wear member, or may be used to hold the wear member 104 on the intermediate adapter. It should be understood that in alternative embodiments, the bore may not extend completely through the adapter. Furthermore, in some embodiments, a first bore may extend to a first side of the adapter and a second bore may extend to a second side of the adapter. In the above embodiments, two locking pin assemblies may be utilized.

[0030] The locking pin assembly 106 is shaped and dimensioned to be received within the wear member 104 and the bore 160 of the adapter 102. As described herein, the locking pin assembly 106 can removably secure the wear member 104 in place on the adapter 102. Furthermore, at least a portion of the locking pin assembly 106 can be manipulated between an unlocked position and a locked position. Once the wear member 104 is properly positioned on the adapter 102, the locking pin assembly 106 can be manipulated from the unlocked position to the locked position. When in the locked position, the locking pin assembly 106 can prevent the wear member 104 from being removed from the adapter 102 by mechanically blocking separation of the wear member 104 from the adapter 102. If desired, a user, such as an operator, can manipulate the locking pin assembly 106 from the locked position to the unlocked position. This allows the user to remove the locking pin assembly 106 from the bore 160 and subsequently remove the wear member 104 from the adapter 102.

[0031] Referring to the exploded view of FIG. 3A , the fixation pin assembly 106 includes, among other things, a body portion 110 and a shaft member 112. The body portion 110 may be a body having an outer surface 146 corresponding to the shape of the bore 160. The shaft member 112 is partially disposed within and extends from a fixation cavity 125, which is an opening in the body portion 110 through the head 124. In some examples, including the example in FIG. 3A , the fixation cavity 125 is a generally cylindrical bore extending partway through the body portion 110. A distal portion of the shaft member 112 has a cylindrical outer surface sized and positioned to fit within the fixation cavity 125. In this embodiment, the shaft member 112 has a clearance fit to allow it to rotate within the fixation cavity 125.

[0032] The shaft member 112 includes a tang portion 126 that projects radially from the shaft member 112 and outward from the body portion 110. The tang portion 126 provides a mechanical interference with the wear member 104 to prevent removal of the locking pin assembly 106 from the bore 160 in a locked position. A tool engagement feature 128 may be used to rotate the shaft member 112 and thereby rotate the tang portion 126, thereby transitioning the locking pin assembly 106 from an unlocked position in which the tang portion 126 passes through a portion of the wear member 104 during insertion and removal, to a locked position in which the tang portion 126 engages a portion of the wear member 104. In this embodiment, the tool engagement feature 128 includes a hexagonal tool recess configured to receive a hexagonal tool, such as a hex wrench, and includes a hexagonal outer surface configured for engagement by an adjustable wrench or socket. It will be apparent to one skilled in the art that other tool interfaces and tools may be used.

[0033] The tool engagement mechanism 128 is sized and arranged to receive a user-operated power tool (not shown) that can be inserted into the tool engagement mechanism 128 and rotated to rotate the shaft member 112, thereby manipulating the locking pin assembly 106 from a locked position to an unlocked position and from the unlocked position to a locked position.

[0034] During rotation, the shaft 112 interacts with the plunger 116 and the biasing member 118 to provide resistance to rotation, thereby preventing inadvertent unlocking and providing tactile feedback to the user. It should be understood that the shaft 112 can be rotated in both directions without axially displacing the shaft 112. In this regard, the shaft 112 can be rotated both clockwise and counterclockwise while experiencing resistance to its rotation due to continuous contact between the shaft 112 and the plunger 116.

[0035] In the illustrated embodiment, the biasing member 118 is a coil spring, but can be any suitable spring or biasing mechanism, and the biasing member 118 rests against the distal wall of the fixed cavity 125 at one end and engages the plunger 116 at the other end. In this regard, the plunger 116 is biased toward the axial member 112 and can resist axial movement that tends to force the plunger 116 further into the fixed cavity 125.

[0036] It may be desirable to prevent rotation of the plunger 116 to ensure that the plunger 116 provides resistance to rotation of the shaft member 112. In that regard, the plunger 116 may have a rotational stop element. In the illustrated embodiment, the rotational stop element comprises a plunger dowel 122 disposed in a dowel recess 123 that intersects with the locking cavity 125. The plunger dowel 122 passes through an elongated opening 134 in the plunger 116. The elongated shape of the elongated opening 134 allows the plunger 116 to slide axially within the locking cavity 125 but not rotate relative to the body portion 110. The plunger dowel 122 is removable from the dowel recess 123 to facilitate disassembly of the locking pin assembly 106, for example, for cleaning or repair, although it should be contemplated that the plunger dowel 122 or another rotational stop element may be integrally formed with the body portion 110.

[0037] In an alternative embodiment, the rotation stop element may include a protrusion extending from the plunger. The protrusion may be disposed within a longitudinal channel formed in the inner wall surface of the fixed cavity 125. In this regard, the plunger 116 may freely slide axially within the fixed cavity 125 as the protrusion slides within the longitudinal channel. However, rotation of the plunger 116 may be prevented by mechanical interference between the protrusion and the sidewall of the longitudinal channel.

[0038] The axial dowel 120 can be positioned within a dowel recess 121 that intersects the fixed cavity 125 and engages a groove 130 on the axial member 112. Like the plunger dowel 122, the axial dowel 120 can be removable or can be permanently affixed to the body portion 110. The groove 130 is positioned to extend substantially transversely to the axial member 112 rather than longitudinally. In this regard, the axial member 112 is rotatable, but axial movement is substantially limited by interference between the axial dowel 120 and the groove 130, as will be described in more detail below with reference to FIGS. 5A-6 . This restriction of axial movement provided by the axial dowel 120 retains the axial member 112 within the fixed cavity 125 and prevents the axial member 112 from displacing in response to forces exerted on the axial member 112 by the plunger 116 during rotation of the axial member 112. It should be understood that the axial dowel 120 and groove 130 are merely exemplary means for limiting axial movement of the axial member 112, and that other suitable means for limiting axial movement of the axial member 112 while allowing rotation are considered within the scope of the present disclosure.

[0039] The interface between the shaft member 112 and plunger 116 may have crowned features that facilitate rotational resistance of the shaft member 112, such as teeth extending from the non-rotatable plunger 116 that grip corresponding teeth extending from the shaft member 112. As described herein, each adjacent pair of teeth on the shaft member 112 forms a notch configured to receive a corresponding tooth on the plunger 116, and vice versa. The furthest extent of the teeth may be referred to as a resistance peak, as this narrowest point of the teeth may correspond to a rotational position where resistance reaches a maximum due to maximum compression of the biasing member 118. When the teeth of one member (the shaft member 112 or the plunger 116) overcome the resistance peak of the other member, resistance may drop to zero as the teeth begin to slide and engage into a seated position. While illustrated as a plurality of jagged teeth, it should be understood that the teeth and notches may be formed from smooth, wavy curves. Such a profile may provide less resistance to rotation than the illustrated embodiment and may have a longer service life or other advantages. In some embodiments, the teeth are shaped to provide approximately equal resistance to rotation in two opposing directions.

[0040] In a preferred embodiment, the shaft 112 and plunger 116 each may have four equidistantly spaced teeth. In this regard, rotation of the shaft 112 from the locked position to the unlocked position involves approximately a 90-degree rotation corresponding to the realignment of the tooth 138 of the shaft 112 from the notch 136a to the adjacent notch 136b of the plunger 116. To return the shaft 112 to the locked position, the rotation may be reversed. Of course, more or fewer teeth may be provided, such as one tooth on one engagement feature and two notches on the other. Alternatively, each engagement feature may have five teeth, ten teeth, or more. The range of rotation between adjacent pairs of teeth or notches may be increased or decreased corresponding to a decrease or increase in the number of teeth and notches.

[0041] In some embodiments, the teeth are selected between about 30 degrees and 120 degrees apart. For example, some embodiments utilize three teeth spaced about 120 degrees apart. Some embodiments utilize 12 teeth spaced about 30 degrees apart.

[0042] As seen in FIG. 3B , each tooth is defined by a resistance peak 137 extending between two notches 136 a, 136 b, and each tooth is oriented at an angle α relative to the direction of rotation of the shaft member 112. It is contemplated that the angle α may be any suitable angle that provides resistance to rotation while still allowing rotation of the shaft member 112. In the illustrated embodiment, the angle α may be approximately 45 degrees to 75 degrees. In one example, the angle α may be approximately 59 degrees. The interaction between each tooth on the shaft member 112 and the corresponding tooth on the plunger 116 converts the rotation into an axial force having a component transverse to the direction of rotation. Because axial movement of the shaft member 112 is limited by the axial dowel 120, this force causes axial displacement of the plunger 116 relative to the biasing member 118 during a first portion of movement corresponding to the upward tilt of one inclined surface of each tooth. A second portion of movement, in which there is no resistance to rotation, begins when the resistance peak of each tooth 138 of the shaft member 112 passes the resistance peak 137 of the corresponding tooth of the plunger 116. Indeed, in some embodiments, rotation is biased during the second portion of movement as the resistance peak of each tooth of the shaft member 112 slides over the downward slope of the corresponding second surface of each tooth of the plunger 116, and the plunger 116 is pushed back to its initial position by the biasing member 118, snapping the shaft member 112 into a fully seated position relative to the plunger 116. In some embodiments, by forming each tooth with two adjacent surfaces of similar slope and similar length, reciprocating movement of the shaft member 112 between locked and unlocked positions relative to the plunger 116 can be facilitated with a similar degree of resistance to that provided by a crowned interface, providing the user with a similar tactile feedback in both directions of rotation confirming the tooth's complete transition from one notch to the adjacent notch. In the illustrated example, where adjacent teeth are 90 degrees apart, the transition from one notch 136a to the adjacent notch 136b of tooth 138 corresponds to a 90 degree rotation between the locked and unlocked positions.

[0043] FIG. 3C illustrates the tip of the plunger of FIG. 3B in an alternative embodiment. In this alternative embodiment, each tooth of the plunger 116 can have a substantially flat segment with a flat surface at the resistance peak 137 and a corresponding flat segment at the base of the notches 136a, 136b. The flat surface can extend between the first and second inclined surfaces that define the plunger teeth. The shaft member 112 can have teeth shaped to correspond to the teeth of the plunger in FIG. 3C. It is contemplated that angle β can be any suitable angle that provides resistance to rotation while still allowing rotation of the shaft member 112. In the illustrated embodiment, angle β can be approximately 60-80 degrees, and in some examples, approximately 72-73 degrees. A larger angle β compared to angle α can increase resistance to rotation and also affect the rotation distance required to achieve full axial displacement. For example, in FIG. 3B, full axial displacement (using the four-tooth example) can be achieved with approximately 90 degrees of rotation. 3C, full axial displacement (using the four tooth example) may be achieved in approximately 60 to 85 degrees of rotation, although it should be understood that other factors, such as the spring constant of biasing member 118, may also affect the rotational resistance provided.

[0044] It should be understood that the functionality described above with respect to the crowned interface may be facilitated by providing a single tooth 138 extending from the shaft member 112 and two notches formed in the plunger 116, or vice versa. However, multiple teeth and multiple notches may be desirable to extend the service life of the locking pin assembly 106 by distributing the forces between the plunger 116 and the shaft member 112 across multiple tooth interfaces. Additionally, distributing multiple teeth and notches symmetrically around the interface may help maintain linear alignment of the plunger 116 and the shaft member 112, thereby preventing binding of the components within the locking cavity 125 and providing predictable and consistent resistance to rotation of the shaft member 112.

[0045] The O-ring 114 may be fitted into the circumferential groove 132 of the shaft member 112. When the locking pin assembly 106 is assembled, the O-ring 114 may provide a seal between the shaft member 112 and the inner wall of the locking cavity 125. This seal may be effective in preventing debris from entering the locking cavity 125 and interfering with the movement of the plunger 116 and biasing member 118.

[0046] 4A and 4B, the assembled locking pin assembly 106 is shown in top and front views, respectively. A reference axis 140 extends longitudinally through the centers of the locking cavity 125, the shaft member 112, and the plunger 116. In the illustrated embodiment, the front side 150 of the body 110 may be defined by a portion of the outer surface 146 that extends parallel to the reference axis 140. This portion of the outer surface 146 may have a small, narrow line extending longitudinally across the front side 150 such that each cross-section through the body 110 is circular, as shown in FIG. 4C. In this regard, some or all of the circular cross-sections may be offset from the reference axis 140. Alternatively, the portion of the outer surface 146 parallel to the reference axis 140 may have a flat surface, which may be flat, such that one or more of the cross-sections are D-shaped.

[0047] In contrast, each of the rear side 151, bottom side 152, and top side 153 may be defined by a portion of the outer surface 146 that is not parallel to the reference axis 140. The rear side 151, bottom side 152, and top side 153 may have a taper that extends from the proximal end 142 of the body portion 110 to the distal end 144 of the body portion 110. That is, the largest outer diameter of the body portion 110, disregarding the head 124, is at the proximal end 142, and the smallest outer diameter of the body portion 110, disregarding the tip 168, is at the distal end 144. The tapered shape of the body portion 110 may improve the ease with which the fixation pin assembly 106 can be removed from the bore 160. That is, due to the extreme compressive and torsional forces that the fixation pin assembly 106 may be subjected to during use, the cylindrical body portion may become wedged within the bore 160, making removal difficult. However, tapered pins, such as the locking pin assembly 106, are more resistant to this problem. The taper between the maximum and minimum outer diameters may be linear or non-linear. Furthermore, the taper on one or more of the rear side 151, bottom side 152, and top side 153 may be asymmetric relative to one or more of the other sides.

[0048] The asymmetrical design of body portion 110 may provide at least two advantages. First, if bore 160 in or through adapter 102 is shaped similarly to exterior surface 146 of body portion 110, it may prevent rotation of locking pin assembly 106. In other words, if the bore is non-circular, the width of body portion 110 from front side 150 to rear side 151 may exceed the height of bore 160, and body portion 110 will not be able to rotate once seated in bore 160. This configuration can be seen, for example, in the alternate cross-sectional view of FIG. 4D.

[0049] Second, the load-bearing capacity of the digging tooth assembly 100 can be improved, particularly if the portion of the outer surface 146 parallel to the reference axis 140 comprises a flat surface. That is, loads applied to the wear member 104 and transferred to the locking pin assembly 106 and adapter 102 can cause excessive wear or failure of the locking pin assembly 106 and / or adapter 102 if the loads are not adequately distributed. For example, a body that is tapered on all sides and mounted within a cylindrical bore will experience greater loads near one end of the body than toward the other end of the body. However, by providing a surface on the body 110 that is parallel rather than tapered to the reference axis 140, the load can be distributed evenly across the leading side 150. Additionally or alternatively, it is contemplated that the trailing side 151 of the outer surface 146 could be provided with a parallel portion to evenly distribute the load during digging when the wear member 104 is pressed toward the rear of the adapter 102.

[0050] 5A and 5B, the shaft member 112 is shown in an unlocked configuration in FIG. 5A and in a locked configuration in FIG. 5B. As shown, the tang portion 126 can be separated from the head 124 of the body portion 110 by a distance L2 when the shaft member 112 is in the unlocked position. When the shaft member 112 is rotated to the locked position, the shaft member 112 can be displaced axially such that the tang portion 126 is separated from the head 124 by a distance L1, which can be zero. This movement is facilitated by forming a groove 130 (see FIG. 3A) having a slight helical direction. Thus, because the shaft dowel 120 remains stationary and fixed in position relative to the body portion 110, rotation of the shaft member 112 pushes the sides of the helical groove 130 formed in the shaft member 112 away from the shaft dowel 120, thereby displacing the shaft member 112 axially. This feature may further contribute to providing tactile feedback to the user. Preferably, the width of groove 130 matches the width of shaft dowel 120 for a tight clearance fit. However, it is contemplated that groove 130 may be wider than shaft dowel 120.

[0051] FIG. 6 is a cross-section taken along line 6-6 of FIG. 4A, further illustrating the interaction of the groove 130 with a rotational stop element, such as the shaft dowel 120. The groove 130 may be partially circumferential, with its length limited and defined by opposing ends of the groove 130. The limited length of the groove 130, in turn, limits the range of rotation of the shaft member 112. In this regard, the shaft dowel 120 located within the dowel recess 121 can mechanically interfere with the rotation of the shaft member 112 and prevent further rotation by contacting multiple ends of the groove 130 as the shaft member 112 rotates. In the illustrated embodiment, the groove 130 is configured with an arc length that allows approximately 90 degrees of rotation, corresponding to the 90 degrees of rotation facilitated by the four equidistant teeth on the shaft member 112 and the plunger 116. This 90-degree range of rotation is sufficient to transition the tang portion 126 from the unlocked position to the locked position and vice versa. However, the grooves 130 can be configured to any length to facilitate any desired range of motion.

[0052] 7-10, Figures 7 and 8 show a front cross-sectional view taken along line 7-7 and a top cross-sectional view taken along line 8-8, respectively, of the digging tooth assembly of Figure 1. Figure 9 shows a left side view of bore 160 of the digging tooth assembly, and Figure 10 shows a cross-sectional view taken along line 10-10 of Figure 8.

[0053] The bore 160 extends through the wear member 104 and the adapter 102 from a proximal opening 162 in a first wall of the wear member 104 to a distal opening 164 in an opposing second wall of the wear member 104. However, as noted above, the bore 160 may alternatively extend only partially into the adapter 102 rather than completely through it, providing a shorter fixation pin assembly corresponding to the shorter bore length.

[0054] As best shown in FIGS. 8-10 , the body portion 110, and specifically the head 124, can be sized and shaped to mechanically couple with the proximal opening 162 at the proximal end of the body portion, and the body portion 110, and specifically the tip 168, can be sized and shaped to mechanically couple with the distal opening 164. Thus, the body portion 110 has a non-circular peripheral profile or shape that, at least at these locations, prevents rotation of the body portion 110 relative to the wear member 104. Furthermore, the snug fit between the body portion 110 and the proximal and distal openings 162, 164 causes the locking pin assembly 106 to move integrally with the wear member 104. Advantageously, this can prevent the wear member 104 from applying force to the tang portion 126 as the wear member 104 moves relative to the adapter 102 during use, which could result in undesirable unlocking.

[0055] As best shown in FIG. 10 , the proximal opening 162 can have an asymmetrical profile, at least a portion of which can be non-circular. In this regard, the asymmetrical shape can assist a user in inserting the locking pin assembly 106 into the bore 160 in the correct orientation. That is, a symmetrical head could lead a user to attempt to insert the locking pin assembly backwards, potentially positioning the portion of the outer surface that is parallel to the reference axis 140 in the wrong area of ​​the bore 160, resulting in improper load distribution across the body. Furthermore, the non-circular portion of the profile of the head 124 can allow the head 124 to seat tightly within at least a portion of the proximal opening 162 in a manner that prevents rotation of the locking pin assembly 106 relative to the wear member 104.

[0056] As shown in Figure 8, the portion of the bore 160 passing through the adapter 102 may be provided with a load bearing surface 166. This load bearing surface may be sized and shaped to closely correspond to the front side 150 of the exterior surface 146 of the body portion 110, which may be parallel to the reference axis 140 as described above in connection with Figure 4A. While the adapter 102 is preferably designed to handle the loads exerted by the wear member 104 and the locking pin assembly 106 in all directions, the load bearing surface 166 may be particularly adapted to ensure an even distribution of the load across the body portion 110.

[0057] Distal opening 164 is sized smaller than the diameter of a portion of body portion 110 to prevent fixation pin assembly 106 from sliding out the distal end of bore 160 and to ensure that fixation pin assembly 106 does not seat so deeply into bore 160 that it becomes wedged and cannot be easily removed. In alternative embodiments, distal opening 164 could be replaced by a distal recess on the inner wall of wear member 104 rather than passing completely through the wall, but in the illustrated embodiment, distal opening 164 is provided as an access point for a tool, such as a perforator, to dislodge fixation pin assembly 106 if it becomes stuck in bore 160. Tip 168 may extend sufficiently into distal opening 164 to allow a user easy access to body portion 110 if it becomes stuck.

[0058] 7 and 8, tang 126 is in a locked position, and mechanical interference of tang 126 with the wall of wear member 104 above proximal opening 162 secures the locking pin assembly within bore 160. Positioning of tang 126 relative to features in the wall of wear member 104 is discussed in more detail below in connection with FIGS. 12-15.

[0059] As discussed above in connection with FIG. 3, FIG. 8 provides an additional view of the plunger dowel 122, the elongated opening 134 in which it is located, as well as the axial dowel 120 and its position relative to the axial member 112 and groove 130.

[0060] Figures 11-15 provide various illustrations of the wear member 104, with particular attention to features associated with the proximal opening 162 of the bore 160. Figure 11 is a right-side perspective view of the wear member. Figure 12 is a partial left-side perspective view of the proximal opening of the wear member. Figure 13 is a perspective view of the proximal opening of Figure 12 as viewed from inside the cavity of the wear member. Figure 14 is a cross-sectional view of the proximal opening, and Figure 15 is a right-side cross-sectional view through the cavity of the wear member.

[0061] The wear member 104 includes an outer surface 170 and an inner surface 172. The inner surface 172 defines a cavity 174 into which the adapter 102 can be inserted. The wear member 104 is comprised of a first wall 176 and a second wall 178 opposite the first wall. The bore 160 extends through both the first wall 176 and the second wall 178 from the proximal opening 162 to the distal opening 164.

[0062] 12 , in the illustrated embodiment, the proximal opening 162 has a profile at the outer surface 170 of the wear member 104 that is substantially D-shaped. The flat wall of this D-shape engages with a similarly flat surface on the head 124, providing resistance to rotation. The proximal opening 162 also has a lobe that extends into the first wall 176 at a portion of its circumference away from the flat wall. This lobe may further ensure that the head 124 is inserted in the correct orientation and does not rotate relative to the wear member 104.

[0063] Within the first wall 176 are two angled surfaces intended to aid in the installation and removal of the locking pin assembly 106. The mounting ramps 182 are configured to engage the proximal side of the tang 126 when it is rotated from the unlocked position to the locked position. The mounting ramps 182 may be located in a proximal region of the first wall 176. As the tang 126 is rotated toward the locked position, the tang 126 slides over the angled mounting ramps 182 into the bore 160. In this regard, rotation of the shaft member 112 is translated into axial movement by the tang 126 sliding over the mounting ramps 182, urging the locking pin assembly 106 into a seated position within the bore 160. The final portion of movement of the tang 126 during rotation to the locked position may correspond to a portion of the mounting ramps 182 that is flat, rather than angled, and oriented transversely relative to the bore 160. The lateral end of the mounting ramp 182 may extend approximately 5-30 degrees of rotation, corresponding to the fully seated position of the locking pin assembly 106. That is, the tang 126 only needs to reach the lateral end when the locking pin assembly 106 is fully inserted into the bore 160. In the illustrated embodiment, the tang 126 does not engage the mounting ramp 182 until it reaches approximately 45 degrees of rotation. In this regard, when a user rotates the tang 126 90 degrees from the unlocked position to the locked position, the tang can rotate disengaged during the first 45 degrees of rotation. At that point, the proximal side of the tang 126 can engage the mounting ramp 182 and begin to slide over the mounting ramp 182. It should be understood that the mounting ramp 182 may extend over a small portion of the rotational range of the tang portion 126 (eg, 5 degrees) or may extend over the entire rotational range of the tang portion 126.

[0064] Due to the orientation of the mounting ramp 182, as the tang 126 slides over the mounting ramp 182, the locking pin assembly 106 is urged further into the bore 160 until the tang 126 is fully seated. At that point, the tang 126 can be rotated another 5 to 25 degrees over the lateral portion of the mounting ramp 182 until the tang 126 is vertical. At this point, the tang 126 can contact the inner wall of the wear member 104, preventing the tang 126 from over-rotating beyond the preferred positioning. Positioning the tang 126 against the lateral end of the mounting ramp 182, which is perpendicular to the direction of removal of the locking pin assembly 106 from the bore 160, can help retain the locking pin assembly 106 within the bore 160.

[0065] A release ramp 184 is located adjacent to the mounting ramp 182. The release ramp 184 may function similarly to the mounting ramp 182, but may engage the distal side of the tang portion 126 as it is rotated from the locked position to the unlocked position. That is, the shaft member 112 may be rotated from the locked position to the unlocked position with the lock pin assembly 106 fully seated. Initially, the tang portion 126 may move through a range of rotation without contacting the release ramp 184. At some point during rotation from the locked position to the unlocked position, for example, approximately 10 to 70 degrees, the tang portion 126 will engage the release ramp 184, which interfaces with the distal side of the tang portion 126, allowing the lock pin assembly 106 to exit the bore 160. This may be particularly advantageous for removal if the lock pin assembly 106 becomes trapped within the bore 160 due to debris or stress.

[0066] In some embodiments, the slope of the mounting ramp 182 and the slope of the removal ramp 184 may be different or may be different at specific locations along the range of rotation of the tang 126. The term "slope," as used with respect to the mounting ramp 182 and the removal ramp 184, refers to the magnitude of axial displacement of the tang 126 caused by the tang 126 moving over a specified distance on the respective ramp. That is, a greater slope refers to the orientation of the ramp's surface that causes a greater axial displacement of the lock pin assembly 106 than a smaller slope. For example, the lateral ends of the mounting ramps may have a slope of substantially zero. In the illustrated embodiment, the mounting ramp 182 may have a smaller slope than the removal ramp 184. In some embodiments, the difference in slope may correspond to a difference in the length of the ramps. For example, a longer mounting ramp 182 may have a smaller slope to distribute the axial displacement of the lock pin assembly 106 over a greater distance. In contrast, the removal ramp 184 may desirably have a greater slope to aid in removing the locking pin assembly 106 if it becomes wedged due to debris or deformation.

[0067] As shown, a gap 186 may be disposed between a portion of the mounting ramp 182 and a portion of the removal ramp 184. The gap 186 is sized to allow the tang portion 126 to pass through the gap 186 during rotation. It should be understood that the removal ramp 184 does not extend through the entire range of rotation of the tang portion 126, but rather, in some embodiments, overlaps with the mounting ramp 182 over a small portion of their respective range of rotation. This feature may advantageously allow the tang portion 126 to be rotated to a position where removal is not clearly impeded by the portion of the first wall 176 comprising the mounting ramp 182 before the tang portion 126 engages the removal ramp 184 and begins to push outward through the proximal opening 162. The overlap between the mounting ramp and the removal ramp (if such overlap exists) may allow the gap 186 to exist in a direction substantially parallel to the longitudinal axis of the proximal opening 162.

[0068] 16 illustrates a method 200 of securing a wear member to an adapter using a locking pin assembly of the present disclosure. Of course, while described in the context of a wear member and an adapter, the method may also be applicable for securing an intermediate adapter to an adapter, or for securing a wear member to an intermediate component. The method may include step 202 of positioning the wear member over the adapter such that the bore is aligned through both the wear member and the adapter. In some embodiments, the bore may pass only partially through the adapter, while in other embodiments, the bore may pass completely through the wear member and the adapter.

[0069] The method may include step 204 of inserting the locking pin assembly, in the unlocked position, into the bore through a proximal opening of the bore in the wear member. Placing the locking pin assembly in the unlocked position allows the tang to pass through a wall of the proximal opening, allowing the locking pin assembly to be inserted. The method may further include step 206 of engaging the shaft member via a tool engagement mechanism, typically operated by a user, and applying a rotational force in a direction that biases the shaft member toward the locked position. The method may include step 208 of rotating the shaft member when the tang contacts a mounting ramp located within or adjacent to the bore. As the tang continues to rotate, the rotation can be translated into axial displacement of the locking pin assembly, seating it at a desired location within the bore.

[0070] The method further includes a first rotating step 210 of rotating the shaft member of the locking pin assembly relative to the body portion of the locking pin assembly in a first direction through a first range of motion in which resistance is provided, and in some embodiments, the resistance is increased by a first engagement feature of the shaft member interacting with a second engagement feature of the plunger. For example, a first surface of a tooth on the shaft member may engage a corresponding first surface of a notch on the plunger disposed in the body portion, while the plunger is substantially rotationally fixed relative to the body portion, and rotation of the shaft member through the first range of motion displaces the plunger axially from an initial position to a compressed position toward the biasing member, thereby providing resistance to rotation.

[0071] The method may further include a second rotation step 212 of rotating the shaft member relative to the body member in a first direction through a second range of motion. During the second range of motion, the first and second engagement features may temporarily disengage or engage to substantially reduce the resistance provided. For example, the second surfaces of the teeth may slide against the corresponding second surfaces of the notches during rotation of the shaft through the second range of motion, and the biasing member may return the plunger to its initial position. During the second rotation, the user may continue to apply a rotational force in the first direction, or may simply allow the first and second engagement features to snap the tang into a fixed position where a portion of the wall of the wear member interferes with axial displacement of the tang in a direction associated with withdrawing the locking pin assembly from the bore.

[0072] In an exemplary embodiment, the rotation between the unlocked and locked positions can span approximately 90 degrees. The first range of motion can range from 10 degrees to 80 degrees, and the second range of motion can range from 10 degrees to 80 degrees. In a preferred embodiment, the first and second ranges of motion each comprise approximately 45 degrees.

[0073] Referring to FIG. 17 , a method 300 for removing a wear member from an adapter in which the wear member is secured by a locking pin is illustrated. The method may include, for example, step 302 of engaging the shaft with a tool and applying a rotational force greater than the resistance provided by the biasing member and plunger interfering with rotation of the shaft. The rotational force may be applied in a direction conducive to moving the tang from the locked position to the unlocked position. Step 304 may include rotating the shaft as it contacts and slides against a removal ramp. This interaction between the tang and the removal ramp may translate into axial displacement of the locking pin assembly in the removal direction from the bore.

[0074] The method further includes step 306 of continuing to apply a rotational force through a first portion of the tang's travel. During the first portion of the travel, the first and second engagement features can interact to continue to provide resistance to rotation. In some embodiments, this resistance can increase during the first portion of the travel. The method can also include step 308 of allowing the shaft member to engage the unlocked position during a second portion of the travel where no resistance to rotation is provided; in fact, such rotation can be biased when the plunger is pushed back to its initial position by the biasing member.

[0075] With the tang in the unlocked position, step 310 of the method may comprise removing the locking pin assembly from the bore through the proximal opening. The method may further comprise step 312 of removing the wear member from the adapter.

[0076] In a preferred embodiment, the first and second portions of movement may each have a range of rotation of about 45 degrees.

[0077] The ranges of motion described herein are intended to be exemplary only for purposes of describing exemplary embodiments. Those skilled in the art should understand that various ranges of motion may be increased or decreased for desired implementations. For example, the range of rotation of the tang between the locked and unlocked positions may be substantially greater than or substantially less than 90 degrees. The proximal opening of the bore may be geometrically reconfigured to have the mounting ramps and / or removal ramps need to extend over a longer or shorter distance to achieve the desired level of axial displacement of the locking pin assembly during rotation.

[0078] The locking pin assemblies described herein may provide benefits and advantages over conventional devices. For example, they may be more resistant to accidental unlocking, bore jamming, and load damage than some conventional pin assemblies. While described with reference to wear members and adapters, it should be understood that the locking pin assemblies may find use in other applications. For example, but not by way of limitation, the locking pin assemblies may be used to attach adapters to buckets or other structures in the ground-engaging tool industry.

[0079] Those skilled in the art will appreciate that the embodiments encompassed by the present disclosure are not limited to the specific exemplary embodiments described above. In that regard, while exemplary embodiments have been shown and described, the foregoing disclosure contemplates a wide range of modifications, variations, combinations, and substitutions. It will be understood that variations can be made to the foregoing without departing from the scope of the present disclosure. Accordingly, it is appropriate that the appended claims be construed broadly and consistent with the present disclosure. The present disclosure also includes the following inventions. The first aspect is 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a body non-rotatably positioned to selectively project into the opening in the support structure, the body having an opening formed therein; a shaft member having a distal end and a proximal end, the distal end having a first engagement feature, the distal end being disposed within the body portion; a tang portion extending radially outward from the body portion from the proximal end of the shaft member, the tang portion being rotatable relative to the body portion between a first position in which the tang portion can be positioned to mechanically prevent removal of the locking pin assembly from the ground engaging member when the tang portion is positioned to secure the ground engaging member to the support structure, and a second position in which the tang portion can be positioned to allow removal of the locking pin assembly from the ground engaging member when the tang portion is positioned to secure the ground engaging member to the support structure; a biasing member disposed within the body; a plunger disposed between the biasing member and the distal end of the axial member, the plunger having a second engagement mechanism configured to selectively engage with the first engagement mechanism of the axial member, the plunger being biased toward the axial member by the biasing member, the second engagement mechanism being configured to engage with the first engagement mechanism to provide resistance during rotation of the axial member relative to the plunger in each of two opposing directions. The second aspect is A first aspect of the fixation pin assembly, wherein the first engagement mechanism and the second engagement mechanism are configured to rotate relative to each other to rotate the shaft member from one of the first position and the second position to the other of the first position and the second position when a rotational force applied to the shaft member exceeds a resistance to rotation applied by the biasing member. The third aspect is A second aspect of the fixation pin assembly is one in which the first engagement mechanism, the second engagement mechanism, and the biasing member are configured such that the resistance to rotation applied by the biasing member occurs during a first portion of the rotational movement and does not occur during a second portion of the rotational movement. The fourth aspect is A third aspect of the fixation pin assembly, wherein one of the first and second engagement mechanisms comprises two adjacent notches separated by a resistance peak, and the other of the first and second engagement mechanisms comprises a tooth configured to selectively seat within each of the two notches. The fifth aspect is A fourth aspect of the fixation pin assembly is one in which the resistance peak comprises a plane extending between a first inclined surface and a second inclined surface, the first inclined surface and the second inclined surface defining opposing sides of one of the first engagement mechanism and the second engagement mechanism. The sixth aspect is In the fixing pin assembly according to a fifth aspect, the first inclined surface and the second inclined surface are angled in the range of approximately 60 degrees to 80 degrees with respect to the rotation direction of the shaft member. A seventh aspect is In a fourth aspect of the invention, the resistance peak is located approximately midway between the two adjacent notches. The eighth aspect is In a seventh embodiment of the fixation pin assembly, the two adjacent notches are centered approximately 90 degrees apart. A ninth aspect is 10. The fixation pin assembly of claim 8, wherein the other of the first and second engagement features includes a third notch, and the resistance peak is sized and shaped to fit into the third notch when the tooth is seated within one of the two adjacent notches. A tenth aspect is In an eighth aspect of the fixation pin assembly, the first engagement mechanism, the second engagement mechanism, and the biasing member are configured to provide tactile feedback to a user confirming the transition from the first position to the second position by rotating the shaft member between the two adjacent notches. An eleventh aspect is A tenth aspect of the fixation pin assembly is one in which the first engagement mechanism, the second engagement mechanism, and the biasing member are configured such that rotation of the shaft member between the two adjacent notches provides tactile feedback to a user confirming the transition from the second position to the first position. A twelfth aspect is A first aspect of the fixation pin assembly further includes a rotation stop element, the shaft member having a partially circumferential groove formed therein, and the rotation stop element configured to mechanically interfere with opposing tips of the groove to limit the range of rotation of the shaft member relative to the main body portion. A thirteenth aspect is A twelfth aspect of the present invention is a fixed pin assembly, wherein the groove extends helically so that engagement of the rotation stop element with the groove converts rotation of the shaft member into axial displacement of the shaft member relative to the body portion. A fourteenth aspect is In a thirteenth aspect, the rotation stop element interfering with the end portion is a fixed pin assembly that limits rotation of the shaft member to a range of approximately 90 degrees relative to the body portion. A fifteenth aspect is The locking pin assembly of a fourteenth aspect, wherein the rotation stop element includes a dowel extending through a portion of the body. A sixteenth aspect is The fixation pin assembly of the first aspect further comprises a second rotational stop element extending from the plunger and configured to prevent rotation of the plunger while allowing axial displacement of the plunger. A seventeenth aspect is A sixteenth aspect of the fixed pin assembly is one in which the second rotation stop element includes a second dowel fixed relative to the main body portion, and the plunger includes an elongated recess into which the second dowel extends. The eighteenth aspect is A sixteenth aspect of the fixed pin assembly is one in which the second rotation stop element includes a protrusion extending from the plunger and fixed relative to the plunger, the protrusion extending into a longitudinal channel formed in the inner wall surface of the main body portion. A nineteenth aspect is A first aspect of the fixation pin assembly is one in which the shaft member and the plunger define a reference axis extending longitudinally, a first cross-section of the body portion perpendicular to the reference axis adjacent the proximal end of the body portion has a first cross-sectional area, a second cross-section of the body portion perpendicular to the reference axis adjacent the distal end of the body portion has a second cross-sectional area smaller than the first cross-sectional area, and the body portion has an engagement surface along only one side parallel to the reference axis. The twentieth aspect is A nineteenth aspect of the present invention is a fixation pin assembly, wherein the fixation pin assembly is configured to be oriented within a bore extending through the ground engagement member into the support structure so that at least a portion of the engagement surface engages with a load-bearing surface of the support structure defined by an inner wall of the bore. A twenty-first aspect is A twentieth aspect of the locking pin assembly, wherein the load bearing surface is located on one side of the bore where the locking pin assembly exerts a force in response to a force that serves to remove the ground engaging member from the support structure. A twenty-second aspect is 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a body non-rotatably positioned to selectively project into the opening in the support structure, the body having an opening formed therein; a shaft member having a distal end and a proximal end, the tip having a first engagement feature, the tip being disposed within a body portion, the shaft member defining a longitudinally extending reference axis; a locking mechanism extending radially from the locking pin assembly, the shaft member being rotatable relative to the body portion between a first position where the locking mechanism can be positioned to mechanically prevent removal of the locking pin assembly from the ground engaging member when the locking mechanism is positioned to secure the ground engaging member to the support structure, and a second position where the locking mechanism can be positioned to allow removal of the locking pin assembly from the ground engaging member when the locking mechanism is positioned to secure the ground engaging member to the support structure; a biasing member disposed within the body; a plunger disposed between the biasing member and the distal end of the shaft, the plunger including a second engagement mechanism configured to selectively engage the first engagement mechanism of the shaft, the plunger being biased toward the shaft by the biasing member, the second engagement mechanism configured to engage the first engagement mechanism to provide resistance during rotation of the shaft relative to the plunger in each of two opposing directions; The body portion is shaped to be received within a bore extending through the ground engaging member and into the support structure, and when attached, the fixed pin assembly is fixed relative to the ground engaging member but movable relative to the support structure. A twenty-third aspect is 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a body portion having an outer surface with a proximal end and a distal end; a head disposed at the proximal end, the head having a periphery, a portion of the periphery having a non-circular shape configured to be received within a correspondingly shaped proximal recess in a wall of the ground engaging member; a tip disposed at the distal end, a portion of the tip having a non-circular peripheral profile configured to be received within a correspondingly shaped distal recess in a portion of the ground engaging member opposite the proximal recess, wherein the head engages the proximal recess and the tip engages the distal recess, thereby preventing rotation of the body portion relative to the ground engaging member. A twenty-fourth aspect is A twenty-third aspect of the fixation pin assembly, wherein the non-circular peripheral profile of the tip has at least one flat side. The 25th aspect is 1. A wear member for mounting on an adapter carried by a ground engaging device using a locking pin assembly, comprising: The wear member is The exterior and an interior surface defining a cavity; a bore passing through the wear member from an outer surface of a first wall to an outer surface of a second wall opposite the first wall; a mounting ramp disposed adjacent the bore, the mounting ramp configured to engage a first surface of a tang portion of the locking pin assembly when the locking pin assembly is disposed within the bore when the tang portion of the locking pin assembly is rotated in a first direction from an unlocked configuration to a locked configuration; a removal ramp disposed adjacent the bore, the removal ramp configured to engage a second surface of the tang portion opposite the first surface of the tang portion when the tang portion of the locking pin assembly is rotated in a second direction opposite the first direction from the locked configuration to the unlocked configuration. A twenty-sixth aspect is A twenty-fifth aspect of the wear member is one in which the mounting ramp and the removal ramp are integral with the first wall. A twenty-seventh aspect is A twenty-sixth aspect of the wear member is one in which the mounting ramp is configured to engage with the first surface to convert rotation of the tang portion in the first direction into axial displacement of the locking pin assembly and facilitate seating of the locking pin assembly in the wear member. A twenty-eighth aspect is A twenty-seventh aspect of the wear member is one in which the removal ramp is configured to convert rotation of the tang portion in the second direction into axial displacement of the locking pin assembly by engaging the removal ramp with the second surface, facilitating removal of the locking pin assembly from the wear member. A twenty-ninth aspect is 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a body portion arranged to selectively project into the opening in the support structure; a shaft member having a distal end and a proximal end, the distal end having a first engagement feature, the distal end disposed within a body portion, the shaft member rotatable relative to the body portion between a locked position for securing the ground engagement member to a support structure and an unlocked position for allowing the ground engagement member to be removed from the support structure; a biasing member disposed within the body; a plunger disposed between the biasing member and the distal end of the axial member, the plunger having a second engagement mechanism configured to selectively engage with the first engagement mechanism of the axial member, the plunger being biased toward the axial member by the biasing member, the second engagement mechanism being configured to engage with the first engagement mechanism to provide resistance during rotation of the axial member relative to the plunger in each of two opposing directions. A thirtieth aspect is A twenty-ninth aspect of the fixation pin assembly is that the first engagement mechanism, the second engagement mechanism, and the biasing member are configured so that resistance to rotation exerted by the biasing member occurs during a first portion of the rotational movement and does not occur during a second portion of the rotational movement, one of the first engagement mechanism and the second engagement mechanism comprises two adjacent notches separated by a resistance peak, and the other of the first engagement mechanism and the second engagement mechanism comprises teeth configured to selectively seat within each of the two notches. A thirty-first aspect is 1. A method for securing a wear member to or removing a wear member from an adapter carried on a ground engaging device using a securing pin assembly, the method comprising: a first rotation step of rotating a shaft member of the locking pin assembly in a first direction relative to a body portion of the locking pin assembly through a first range of motion in which first surfaces of teeth of the shaft member engage corresponding first surfaces of notches of a plunger disposed in the body portion, the plunger being substantially rotationally fixed relative to the body portion, and rotation of the shaft member through the first range of motion causing a biasing member to axially displace the plunger from an initial position toward a compressed position; a second rotation step of rotating the shaft member in the first direction relative to the body portion through a second range of motion in which second surfaces of the teeth slide against corresponding second surfaces of the notches, wherein the biasing member returns the plunger to the initial position during rotation of the shaft member through the second range of motion; the first rotation step and the second rotation step move a locking mechanism extending from the locking pin assembly from a first configuration to a second configuration; when the locking mechanism is in one of the first and second configurations, the locking mechanism engages with the wear member or the adapter to prevent withdrawal of the locking pin assembly from the wear member; a second rotating step in which the locking pin assembly is removable from the wear member when the locking mechanism is in the other of the first and second configurations. A thirty-second aspect is A thirty-first aspect is the method, wherein the first range of movement comprises a range of 0 degrees to 180 degrees, and the second range of movement comprises a range of 0 degrees to 180 degrees. A thirty-third aspect is 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a body non-rotatably positioned to selectively project into the opening in the support structure, the body having an opening formed therein; a shaft member having a first axis and including a distal end and a proximal portion, the distal end having a first plurality of equidistantly spaced teeth spaced radially about the first axis between about 30 degrees and 120 degrees, the distal end disposed within the body portion; a tang portion extending radially outward from the body portion from the proximal end of the shaft portion, the tang portion being rotatable relative to the body portion between a first position in which the tang portion can be positioned to mechanically prevent removal of the locking pin assembly from the ground engaging member when the shaft portion is positioned to secure the ground engaging member to the support structure, and a second position in which the tang portion can be positioned to allow removal of the locking pin assembly from the ground engaging member when the shaft portion is positioned to secure the ground engaging member to the support structure; a biasing member disposed within the body; a plunger disposed between the biasing member and the distal end of the axial member, the plunger having a second axis and including a second plurality of equally spaced teeth, the second plurality of equally spaced teeth being radially spaced about the second axis in a range of between approximately 30 degrees and 120 degrees and shaped to selectively engage the first plurality of equally spaced teeth of the axial member to provide resistance to rotation in two opposing directions. A thirty-fourth aspect is A thirty-third aspect of the fixation pin assembly, wherein the first plurality of equally spaced teeth and the second plurality of equally spaced teeth are shaped to provide approximately equal resistance to rotation in two directions. The thirty-fifth aspect is A thirty-third aspect of the fixation pin assembly is one in which the first plurality of equally spaced teeth and the second plurality of equally spaced teeth are configured to rotate relative to each other when a rotational force applied to the shaft member exceeds the resistance to rotation applied by the biasing member, causing the shaft member to rotate from one of the first position and the second position to the other of the first position and the second position. A thirty-sixth aspect is A thirty-fifth aspect of the invention is a locking pin assembly, wherein the first plurality of equally spaced teeth, the second plurality of equally spaced teeth, and the biasing member are configured such that resistance to rotation applied by the biasing member occurs during a first portion of the rotational movement and does not occur during a second portion of the rotational movement. A thirty-seventh aspect is 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a body non-rotatably positioned to selectively project into the opening in the support structure, the body having an opening formed therein; a shaft member having a first axis and including a distal end and a proximal portion, the distal end having a first tooth extending axially and offset from the first axis, the distal end being disposed within the body portion; a tang portion extending radially outward from the body portion from the proximal end of the shaft portion, the tang portion being rotatable relative to the body portion between a first position in which the tang portion can be positioned to mechanically prevent removal of the locking pin assembly from the ground engaging member when the shaft portion is positioned to secure the ground engaging member to the support structure, and a second position in which the tang portion can be positioned to allow removal of the locking pin assembly from the ground engaging member when the shaft portion is positioned to secure the ground engaging member to the support structure; a biasing member disposed within the body; a plunger disposed between the biasing member and the distal end of the shaft member, the plunger having a second axis and including second teeth extending proximally and offset from the second axis, the second teeth engaging the first teeth to provide resistance to rotation in two opposing directions. A thirty-eighth aspect is A thirty-seventh aspect of the fixation pin assembly is one in which one of the shaft member and the plunger has a notch adjacent to each of the first teeth or second teeth, and each of the first teeth and second teeth is dimensioned to form a radial arc within a range of approximately 30 degrees to 120 degrees about the first axis and the second axis, respectively.

Claims

1. 1. A fixation pin assembly for securing a ground engaging member to a support structure, comprising: The fixing pin assembly includes: a rotatable fixed part; a body coupled to the rotatable fixture, the body having an outer surface with a proximal end and a distal end; a head disposed at the proximal end, the head having a periphery integral therewith, a portion of the periphery having a non-circular shape configured to be received within a correspondingly shaped proximal recess in a wall of the ground engaging member; a tip disposed at the distal end, a portion of the tip having a non-circular peripheral profile configured to be received within a correspondingly shaped distal recess in a portion of the ground engaging member opposite the proximal recess, wherein engagement of the head with the proximal recess and engagement of the tip with the distal recess prevents rotation of the body portion relative to the ground engaging member.

2. The fixation pin assembly of claim 1 , wherein said non-circular peripheral profile of said tip has at least one flat side.

3. 2. The fixation pin assembly of claim 1, wherein a reference axis extends longitudinally through said body portion, and a portion of said outer surface includes an engagement surface along a first side that is parallel to said reference axis.

4. 4. The fixation pin assembly of claim 3, wherein a portion of said outer surface opposite said engagement surface is non-parallel to said reference axis.

5. 4. The fixation pin assembly of claim 3, wherein said first side is a front side of said body portion, and said top, bottom and rear sides of said body portion are non-parallel to said front side.

6. 6. The fixation pin assembly of claim 5, wherein said first side is a rear side of said body portion.

7. 6. The fixation pin assembly of claim 5, wherein each of said top, bottom and rear sides is tapered such that an outer diameter near said distal end is smaller than an outer diameter near said proximal end.

8. 6. The fixation pin assembly of claim 5, wherein the width of said body portion from said front side to said rear side exceeds the height of said body portion from said bottom side to said top side.

9. 4. The fixation pin assembly of claim 3, wherein each cross section between said head and said tip transverse to said reference axis is circular.

10. 4. The fixation pin assembly of claim 3, wherein each cross section between said head and said tip transverse to said reference axis is non-circular.

11. The fixation pin assembly of claim 3 , wherein the engagement surface comprises a flat surface.

12. 1. A wear member assembly attachable to a nose having a bore, comprising: The wear member assembly includes: a wear member having a cavity sized to receive the nose; a locking pin assembly configured to secure the wear member to the nose, The fixing pin assembly includes: a body portion having an outer surface with a proximal end and a distal end; a head disposed at the proximal end, the head having a periphery integral therewith, a portion of the periphery having a non-circular shape configured to be received within a correspondingly shaped proximal recess in a wall of the wear member; a tip disposed on the distal end, a portion of the tip having a non-circular peripheral profile configured to be received within a correspondingly shaped distal recess in a portion of the wear member opposite the proximal recess, the head engaging the proximal recess and the tip engaging the distal recess thereby preventing rotation of the body portion relative to the wear member.

13. 13. The wear member assembly of claim 12, wherein a reference axis extends longitudinally through the body portion of the fixation pin assembly, and a portion of the outer surface includes an engagement surface along a first side that is parallel to the reference axis.

14. The wear member assembly of claim 13, wherein the reference axis is centered within a bore formed in the body portion.

15. 15. The wear member assembly of claim 14, wherein the first side is a front side of the body portion, and the top, bottom, and rear sides of the body portion are non-parallel to the front side.

16. The wear member assembly of claim 13 , wherein a portion of the outer surface opposite the engagement surface is non-parallel to the reference axis.

17. 14. The wear member assembly of claim 13, wherein an inner wall defining the bore in the nose comprises a load bearing surface, and the locking pin assembly is configured to be oriented within the bore such that at least a portion of the engagement surface engages the load bearing surface.

18. The load bearing surface is disposed on a front side of the bore, and the locking pin assembly includes: The wear member assembly of claim 17 configured to exert a force against the front side of the bore in response to a force tending to remove the wear member from the nose.

19. 14. The wear member assembly of claim 13, wherein each cross section between the head and the tip transverse to the reference axis is circular.

20. 14. The wear member assembly of claim 13, wherein each cross section between the head and the tip transverse to the reference axis is non-circular.

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