Oscillating pivot structure and work machine equipped therewith

Abstract

The present invention provides a pivot support structure for a rocking body that can reliably connect the pivot and the anti-rotation pin portion with an anti-rotation member, even if the accuracy of the fixing position of the anti-rotation pin portion in the rocking body is insufficient, and a work machine equipped therewith. [Solution] The oscillating pivot structure comprises a pivot, a first member and a second member pivotally connected to each other via the pivot so as to be able to swing relative to each other, and an anti-rotation member attached to the pivot. The anti-rotation member has an insertion portion into which the anti-rotation pin portion of the first member is inserted. The insertion portion has a first width in the direction along the first straight line of the pivot and a second width in the direction along the second straight line. The first width is such that the anti-rotation pin portion can be repositioned in the insertion portion in the direction along the first straight line. The second width is such that the anti-rotation pin portion contacts the anti-rotation member at least one end of the insertion portion in the direction along the second straight line, thereby restricting the relative movement between the anti-rotation member and the anti-rotation pin portion in the direction along the second straight line.

Description

Technical Field

[0001] The present invention relates to a swing body pivot support structure and a working machine provided with the same.

Background Art

[0002] Conventionally, in a working machine such as a backhoe, a structure for preventing rotation around a pivot for connecting a swing body is used. For example, Patent Document 1 discloses a configuration in which a rotation prevention plate is fixed to one end of a support pin for swingably connecting a boom to a boom bracket, and the end of the rotation prevention plate is bolted to the boom bracket (swing bracket).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology shown in Patent Document 1 and the like, there is a problem that when a force in a direction perpendicular to the axial direction of the support pin acts due to swinging of the boom or vibration of the machine body, the bolts are likely to loosen. Therefore, it is conceivable to fix a boss to the boom bracket (swing bracket) and insert this boss into a hole provided at the end of the rotation prevention plate to prevent rotation. However, in that case, there is a problem that it becomes difficult to assemble the support pin when sufficient mounting accuracy of the boss cannot be obtained.

[0005] For example, when the main body and boss of a boom bracket (swing bracket) are integrally molded by casting, errors may occur in the formation position of the boss during the casting process. When the boss is attached to the main body by welding, errors in the welding position are possible. Furthermore, when the boss is fastened to the main body with bolts or the like, errors in the formation position of the screw holes are possible. If such errors occur, the mounting position of the support pin on the anti-rotation plate and the position of the boss will not match, making it difficult to connect the pivot and the boom bracket (swing bracket) etc. using the anti-rotation plate.

[0006] The object of the present invention is to provide a pivot structure for a swinging body that can solve the above-mentioned problems, and a work machine equipped therewith. [Means for solving the problem]

[0007] A pivot support structure according to one aspect of the present invention comprises a pivot, a first member and a second member pivotally connected to each other via the pivot so as to be able to swing relative to each other, and an anti-rotation member attached to the pivot, wherein the first member has a main body, an axial hole provided in the main body through which the pivot is inserted, and an anti-rotation pin portion protruding from the main body in a direction substantially parallel to the axis of the pivot near the axial hole, the anti-rotation member has a first end fixed to the pivot and a second end provided with an insertion portion into which the anti-rotation pin portion is inserted, and the insertion portion extends along a virtual first straight line that coincides with one radial direction of the pivot and passes through the first end and the second end The insert has a first width between both ends in one direction and a second width between both ends in a direction along a virtual second straight line perpendicular to the axis of the pivot and the first straight line, wherein the first width is large enough to allow the inserted anti-rotation pin portion to be repositioned in the direction along the first straight line, and the second width is larger than or equal to the width of the anti-rotation pin portion in the direction along the second straight line, and is large enough to restrict the relative movement between the anti-rotation member and the anti-rotation pin portion in the direction along the second straight line by allowing the anti-rotation pin portion inserted into the insert to abut against the anti-rotation member at at least one end of the insert in the direction along the second straight line.

[0008] Furthermore, a work machine according to one aspect of the present invention comprises a machine body and the oscillating pivot structure. The oscillating pivot structure is provided as a pivot point between a boom pivotably supported on the machine body and an arm pivotably supported on the boom, a pivot point between the machine body and a work device pivotably supported on the machine body, or a pivot point between the work device and a work tool pivotably supported on the work device. [Effects of the Invention]

[0009] In the pivot support structure of the oscillating body described above, even if the precision of the fixing position of the anti-rotation pin portion to the main body is insufficient in the configuration of the first member, the first width of the insertion portion of the anti-rotation member is large enough to accommodate such a condition. Therefore, the anti-rotation pin portion can be reliably inserted into the insertion portion, and the anti-rotation action of the anti-rotation member can be reliably applied to the anti-rotation pin portion at both ends in the direction of the second width of the insertion portion.

[0010] Furthermore, in the work machine with the above configuration, the effect of the pivot support structure for the oscillating body can be applied to the pivot point of the oscillating body as described above. [Brief explanation of the drawing]

[0011] [Figure 1] This is a side view of a rotary excavating machine (hereinafter simply referred to as "the machine"). [Figure 2] This is a side view of a pivot structure for a swing body equipped with an anti-rotation member according to one embodiment. [Figure 3] This is a perspective view of the aforementioned pivot structure for the oscillating body. [Figure 4A] This is a side view of the pivot structure of the oscillating body with the retaining member removed. [Figure 4B] This is an enlarged side view of the pivot structure of the oscillating body with the retaining member removed. [Figure 5] This is a perspective view of the pivot structure of the oscillating body with the retaining member removed. [Figure 6A] This is a side view of a pivot structure for a rocking body equipped with an anti-rotation member according to another embodiment, with the anti-detachment member removed. [Figure 6B] This is an enlarged side view of a pivot structure for a rocking body equipped with a rotation-preventing member according to another embodiment, with the retaining member removed. [Figure 7] This is a perspective view of a pivot structure for a rocking body equipped with an anti-rotation pin, which is another embodiment of the anti-rotation pin portion, and is partially an exploded view. [Modes for carrying out the invention]

[0012] Figure 1 is a side view of the rotary excavation work machine 1 (hereinafter simply referred to as "work machine 1"). The general configuration of work machine 1 will be explained with reference to Figure 1. In this embodiment, the direction of arrow A1 in Figure 1 is the forward direction, and the direction of arrow A2 is the rear direction. The direction perpendicular to arrows A1 and A2, towards the foreground of Figure 1, is considered left, and the direction toward the background of Figure 1 is considered right.

[0013] The work machine 1 comprises a traveling body 10, a machine body 20, and a work device 30. The machine body 20 is mounted on the upper part of the traveling body 10 (specifically the traveling frame 11 described later) via a swivel joint having a vertical axis Xv as shown in Figure 1. The machine body 20 can rotate (swivel) horizontally relative to the traveling body 10 around this axis Xv by a hydraulic swivel motor (not shown).

[0014] The traveling body 10 has a traveling frame 11 and a pair of left and right traveling devices 12, each traveling device 12 being driven by a hydraulic traveling motor (not shown). A dozer 13 is also provided at the front of the traveling body 10. The dozer 13 has blades 13a positioned in front of the pair of left and right traveling devices 12, and actuators (hydraulic cylinders) for swinging the blades up and down.

[0015] Furthermore, the swing bracket 14 is supported by the machine body 20 via a swing pin (pivot) 14a having an axis in the vertical direction, and the entire working device 30, together with the swing bracket 14, can rotate (oscillate) horizontally relative to the machine body 20 by a swing cylinder (hydraulic cylinder) not shown in Figure 1.

[0016] The working device 30 is swingably supported by the machine body 20, and a working tool (working attachment) is attached to the working device 30 and swingably supported. In the present embodiment, the working device 30 is a backhoe-type working device 30 including a boom 31 and an arm 32, and a bucket 33 is attached to the working device 30 as the working tool.

[0017] In the working device 30, the base end portion of the arm 32 is swingably pivotally supported at the tip end portion of the boom 31, and the base end portion of the boom 31 is pivotally supported by the swing bracket 14, so that the entire working device 30 is supported by the machine body 20 via the swing bracket 14. On the other hand, the bucket 33 as the working tool is pivotally supported at the tip end portion of the arm 32, and thus is swingably supported by the working device 30.

[0018] The boom 31, the arm 32, and the bucket 33 of the working tool of the working device 30 are respectively driven by a boom cylinder (hydraulic cylinder) 34, an arm cylinder (hydraulic cylinder) 35, and a bucket cylinder (hydraulic cylinder) 36 provided in the working device 30.

[0019] Among these, the basic configuration of the boom 31 shown in FIG. 1 will be described in a little more detail. The boom 31 shown in FIG. 1 originally has a tip end portion 31c, a base end portion 31d which are originally separate members from each other, and a main portion 31e interposed between the tip end portion 31c and the base end portion 31d, and is configured by connecting the tip end portion 31c and the base end portion 31d via the main portion 31e. Among these, the tip end portion 31c and / or the base end portion 31d are components of the swing body pivot support structure P described later.

[0020] The tip end portion 31c and / or the base end portion 31d may be, for example, a solid or hollow single member in which all or part of them are integrally formed by casting or the like, or may be configured by combining a plurality of plate materials (such as steel plate materials) by welding or the like, or bending a single plate material (such as steel plate material) so as to have a rectangular cross-sectional view.

[0021] Furthermore, the main part 31e may be constructed by combining multiple plate materials (steel plates, etc.) by welding, or by bending a single plate material (steel plates, etc.) so that it has a rectangular cross-section, but it may also be a single component integrally formed by casting, etc. The boom 31 is completed by connecting one end of the main part 31e constructed in this way to the tip part 31c and the other end to the base part 31d by welding, etc.

[0022] Alternatively, the tip portion 31c and / or base portion 31d may be extended and directly connected to each other by welding or the like, instead of the main portion 31e. Furthermore, the boom 31 may be composed entirely of a single member from its base to its tip.

[0023] The working device 30 has at least one pivot point to which the first member and the second member, which are oscillating members, are pivotally connected. The backhoe-type working device 30 according to this embodiment has a first pivot point to which the tip of the boom 31 and the base end of the arm 32 are pivotally connected, a second pivot point to which the base end of the boom 31 of the working device 30 and the swing bracket 14 of the machine body 20 are pivotally connected, and a third pivot point to which the tip of the arm 32 of the working device 30 and the bucket bracket 33a of the bucket 33, which is a work tool, are pivotally connected.

[0024] At least one of the first to third pivot points is provided with a swinging body pivot structure P comprising a pivot 2, a first member and a second member pivotally connected to each other via the pivot 2 so as to be able to swing relative to each other, and an anti-rotation member attached to the pivot 2. In other words, in the work machine 1, at least one of the first pivot point of the boom 31 and arm 32, the second pivot point of the machine body 20 (swing bracket 14) and work device 30 (boom 31), and the third pivot point of the work tool (bucket 33) and work device 30 (arm 32) is configured as a swinging body pivot structure P.

[0025] As described above, the oscillating pivot structure P, comprising the pivot 2, the first member, the second member, and the anti-rotation member, is defined to have at least the following configuration. Specifically, the first member has a main body, an axial hole provided in the main body through which the pivot is inserted, and an anti-rotation pin portion that protrudes from the main body in a direction substantially parallel to the axis of the pivot near the axial hole. The anti-rotation plate member has a first end fixed to the pivot 2 and a second end provided with an insertion portion into which the anti-rotation pin portion is inserted. The insertion portion has a first width between its ends in the direction along a virtual first straight line Dr (see Figure 4B or Figure 6B) that extends in a direction consistent with one radial direction of the pivot 2 and passes through the first and second ends, and a second width between its ends in the direction along a virtual second straight line Dt (see Figure 4B or Figure 6B) perpendicular to the axis 2a of the pivot 2 and the first straight line Dr. The first width is such that the inserted anti-rotation pin portion can be repositioned in the insertion portion along the first straight line Dr. The second width is such that the anti-rotation pin portion is greater than or equal to the width of the anti-rotation pin portion in the direction along the second straight line Dt, and is such that the anti-rotation pin portion inserted into the insertion portion abuts the anti-rotation member at at least one end of the insertion portion in the direction along the second straight line Dt, thereby restricting the relative movement between the anti-rotation member and the anti-rotation pin portion in the direction along the second straight line Dt.

[0026] Here, in the work machine 1, if the oscillating pivot structure P is provided as the first pivot point between the boom 31 and the arm 32, the oscillating pivot structure P shall be referred to as the first oscillating pivot structure P1. Furthermore, if the oscillating pivot structure P is provided as the second pivot point between the boom 31 and the machine body 20 (swing bracket 14), the oscillating pivot structure P shall be referred to as the second oscillating pivot structure P2. Furthermore, if the oscillating pivot structure P is provided as the third pivot point that pivots the first member and the work tool (bucket 33) and the arm 32 as the second member, the oscillating pivot structure P shall be referred to as the third oscillating pivot structure P3.

[0027] As shown in Figure 1, in the first oscillating body pivot structure P1, the boom 31 is the first member of the oscillating body and the arm 32 is the second member of the oscillating body, and they are pivotally connected to each other via a pivot 2. That is, the tip portion 31c of the boom 31 corresponds to the main body portion of the first member, and the tip portion 31c is provided with an axial hole 31a through which the pivot 2 is inserted and an anti-rotation pin portion 31b which is inserted into the insertion portion of the anti-rotation plate 3 (anti-rotation member).

[0028] The boom 31 may be the second member and the arm 32 may be the first member. In this case, the base end of the arm 32, which is the main body of the first member, is provided with an axial hole through which the pivot 2 is inserted and an anti-rotation pin portion that is inserted into the insertion portion of the anti-rotation member.

[0029] Furthermore, as shown in Figure 1, in the second oscillating body pivot structure P2, the boom 31 of the working device 30 is the first member of the oscillating body, and the swing bracket 14 of the machine body 20 is the second member of the oscillating body, and they are pivotally connected to each other via the pivot 2. That is, the base end 31d of the boom 31 corresponds to the main body of the first member, and the base end 31d is provided with an axial hole through which the pivot 2 is inserted, and an anti-rotation pin portion which is inserted into the insertion part of the anti-rotation plate 3 (anti-rotation member).

[0030] In addition, the boom 31 of the working device 30 may be the second member, and the swing bracket 14 of the machine body 20 may be the first member. In this case, the upper part of the swing bracket 14, which is the main body of the first member, is provided with an axial hole through which the pivot 2 is inserted, and an anti-rotation pin portion that is inserted into the insertion portion of the anti-rotation member.

[0031] Furthermore, as shown in Figure 1, in the third oscillating body pivot structure P3, the bucket 33, which is a work tool, is the first member, and the arm 32 of the work device 30 is the second member, and they are pivotally connected to each other via the pivot 2. That is, the bucket bracket 33a of the bucket 33 corresponds to the main body of the first member, and the bucket bracket 33a is provided with an axial hole through which the pivot 2 is inserted, and an anti-rotation pin portion that is inserted into the insertion part of the anti-rotation plate 3 (anti-rotation member).

[0032] In addition, the arm 32 of the work device 30 may be the second member, and the bucket 33 of the work tool may be the first member. In this case, the tip of the arm 32, which is the main body of the first member, is provided with an axial hole through which the pivot 2 is inserted, and an anti-rotation pin portion that is inserted into the insertion portion of the anti-rotation member.

[0033] In the work machine 1 of this embodiment shown in Figure 1, all of the first oscillating body pivot structures P1 to the third oscillating body pivot structures P3 are provided, but it is also possible that only one or two of these are provided (i.e., one or two of the first to third pivot sections are equipped with an oscillating body pivot structure P).

[0034] Furthermore, the oscillating pivot structure P is not limited to excavating machines (backhoes) as shown in Figure 1; it can be widely adopted in any machine equipped with an oscillating body. For example, skid steer loaders and track loaders, which are equipped with a work device including an oscillating body such as a boom and to which work tools can be attached in a swingable manner, can also adopt the oscillating pivot structure P.

[0035] Furthermore, the oscillating pivot structure P (i.e., the third oscillating pivot structure P3) can be adopted not only in buckets 33 as shown in Figure 1, but also in a wide range of other work tools that can be swingably attached to the work equipment of a work machine, such as breakers and earth drills, which are equipped with a hydraulic actuator that is fluidly connected to the hydraulic output (AUX) port of the work machine when attached to an excavating machine (backhoe), and have a structure that allows them to be swingably attached to the work equipment.

[0036] The specific configuration of the oscillating body pivot structure P1, as a representative example of the oscillating body pivot structure P, will be described below with reference to Figures 2 to 5. Figure 2 is a side view of the oscillating body pivot structure P1(P) equipped with an anti-rotation member (anti-rotation plate 3) according to one embodiment. Figure 3 is a perspective view of the oscillating body pivot structure P1(P). Figure 4A is a side view of the oscillating body pivot structure P1(P) with the anti-detachment member (anti-detachment plate 5) removed. Figure 4B is an enlarged side view of the oscillating body pivot structure P1(P) with the anti-detachment member (anti-detachment plate 5) removed. Figure 5 is a perspective view of the oscillating body pivot structure P1(P) with the anti-detachment member (anti-detachment plate 5) removed.

[0037] In the oscillating body pivot structure P1(P), the boom 31, which corresponds to the first member, has a main body portion 31c, an axial hole 31a provided in the main body portion 31c through which the pivot 2 is inserted, and an anti-rotation pin portion 31b that protrudes from the main body portion 31c in a direction substantially parallel to the axis 2a of the pivot 2 near the axial hole 31a.

[0038] An example of an anti-rotation member, the anti-rotation plate 3, has a first end 3b fixed to the pivot 2 and a second end 3d provided with a notch 3e, which is an example of an insertion part into which the anti-rotation pin portion 31b is inserted. Referring to Figure 4B, the notch 3e, which is an example of an insertion part, has a first width Wr between both ends 3e1 and 3e2 in the direction along a virtual first straight line Dr that extends to pass through the first end 3b and the second end 3d, coinciding with one radial direction of the pivot 2, and a second width Wt between both ends 3e3 and 3e4 in the direction along a virtual second straight line Dt perpendicular to the axis 2a of the pivot 2 and the first straight line Dr.

[0039] The first width Wr is such that the anti-rotation pin portion 31b inserted in the notch 3e can be repositioned in the direction along the first straight line Dr. The second width Wt is such that the anti-rotation pin portion 31b is greater than or equal to the width Wp in the direction along the second straight line Dt, and the anti-rotation pin portion 31b inserted in the notch 3e contacts the anti-rotation plate 3 at at least one of the ends 3e3·3e4 of the insertion portion 3e in the direction along the second straight line Dt, thereby restricting the relative movement of the anti-rotation plate 3 with respect to the anti-rotation pin portion 31b in the direction along the second straight line Dt.

[0040] The pivot structure P1 described above will now be explained in more detail. In the pivot structure P1 at the first pivot point between the boom 31 and the arm 32, the tip portion 31c of the boom 31 corresponds to the main body portion of the first member of the pivot structure P. That is, the tip portion 31c of the boom 31, which is the main body portion, is equipped with an axial hole 31a and an anti-rotation pin portion 31b.

[0041] Therefore, the tip portion 31c is made of a member having a size (length and width) and strength sufficient to accommodate the shaft hole 31a and the anti-rotation pin portion 31b. As mentioned above, the tip portion 31c may be integrally formed by casting, for example, or it may be constructed by processing one or more plate materials (steel plates, etc.) by welding, bending, etc.

[0042] Furthermore, the shaft hole 31a may be integrally formed with the cast tip portion 31c, or it may be formed by drilling a solid member. Also, the anti-rotation pin portion 31b may be integrally formed with the cast tip portion 31c, or it may be originally a separate member from the tip portion 31c and fixed (integrated) to the tip portion 31c by welding or the like.

[0043] In this way, the anti-rotation pin portion 31b is integrated with the tip portion 31c (main body portion of the first member) of the boom 31 by processing methods such as casting or welding, so that even if force is applied to the anti-rotation pin portion 31b from the pivot 2 via the anti-rotation plate 3, the anti-rotation pin portion 31b has sufficient rigidity to prevent it from falling off or shifting position from the boom 31.

[0044] Alternatively, the anti-rotation pin portion may be a separate component from the main body of the first member, such as the tip portion 31c of the boom 31, and may be fastened to the main body of the first member with fasteners such as bolts. Figure 7 shows a pivot structure P1(P) equipped with an anti-rotation pin 6, which is another embodiment of such an anti-rotation pin portion, and will be described in detail later.

[0045] The end of the horizontally axial shaft hole 31a opens on the front surface of the tip portion 31c of the boom 31 (the main body portion of the first member of the oscillating pivot structure P). A pivot 2 having a horizontal axis 2a is inserted through the shaft hole 31a, and the end of the pivot 2 protruding from the opening of the shaft hole 31a is fixed in a flange-like manner to the base end (first end) 3a side of a rotation-preventing plate 3, which is a plate material as an example of a rotation-preventing member 3. The portion of the rotation-preventing plate 3 that is arranged in a flange-like manner to surround the pivot 2, including the base end (first end) 3a, is called the first end portion 3b.

[0046] Furthermore, the pivot 2 and the anti-rotation plate 3 (first end portion 3b) may be connected by welding, or they may be integrally molded together by casting or the like. In other words, as long as the pivot 2 and the anti-rotation plate 3 remain fixed without relative rotation even when a force is applied in the rotational direction around the axis of the pivot 2, the pivot 2 and the anti-rotation plate 3 may be fixed in any manner.

[0047] Near the shaft hole 31a, a boss-shaped anti-rotation pin portion 31b protrudes horizontally from the front surface of the tip portion 31c of the boom 31. The anti-rotation plate 3 is a plate-shaped member that extends radially along the pivot 2 from its base end (first end) 3a to its tip end (second end) 3c, which is positioned around the anti-rotation pin portion 31b, and spreads parallel to the side surface of the tip portion 31c of the boom 31.

[0048] An insertion portion for inserting the anti-rotation pin portion 31b is provided near the tip 3c of the anti-rotation plate 3. In this embodiment, a notch 3e that opens at the tip 3c is provided as the insertion portion. The portion of the anti-rotation plate 3 that surrounds the notch 3e, including the tip (second end) 3c, is called the second end portion 3d. In other words, in the anti-rotation plate 3 according to this embodiment, the second end portion 3d formed along the notch 3e, including the tip (second end) 3c, is bifurcated.

[0049] The anti-rotation plate 3 is configured such that when the distance between the shaft hole 31a and the anti-rotation pin portion 31b (hereinafter referred to as "the said distance") on the boom 31 is at a reference value (average value, etc.), the anti-rotation pin portion 31b is positioned near the opening end of the notch 3e (the second end 3e2 described later). This configuration allows for a reduction in the length of the anti-rotation plate 3 from the base end 3a to the tip end 3c, contributing to cost reduction and weight reduction of the parts.

[0050] Here, with reference to Figure 4B, the configuration of the notch 3e as an insertion part in this embodiment will be described. In the side view of the boom 31 (tip 31c) shown in Figure 4B, it is assumed that a virtual first straight line Dr is drawn that passes through the axis 2a of the pivot 2 (i.e., coincides with one radial direction of the pivot 2) and passes through the first end 3b (including the joint to the end of the pivot 2) and the second end 3d (including the notch 3e as an insertion part) of the anti-rotation plate 3, and a virtual second straight line Dt is drawn that extends perpendicular to the first straight line Dr and the axis 2a of the pivot 2.

[0051] In other words, the first straight line Dr is a straight line extending radially along the pivot 2, and the second straight line Dt is a straight line extending tangentially at the intersection of the radial line and the outer circumference of the pivot 2 along the first straight line Dr. Therefore, the direction along the second straight line Dt substantially coincides with the direction of rotation about the axis 2a of the pivot 2.

[0052] The notch 3e, which is the insertion part into which the anti-rotation pin portion 31b is inserted, is required to have a margin in the direction along the first straight line Dr that can absorb dimensional errors in the distance between the shaft hole 31a (through which the pivot 2 is inserted) at the tip portion 31c of the boom 31 and the anti-rotation pin portion 31b, while in the direction along the second straight line Dt that it is required to be precise enough to restrict the relative rotation between the anti-rotation plate 3 (integrated with the pivot 2) and the anti-rotation pin portion 31b (integrated with the boom 31) with respect to the axis 2a of the pivot 2.

[0053] In the anti-rotation plate 3 according to this embodiment, the notch 3e, which serves as an insertion portion for inserting the anti-rotation pin portion 31b, has two opposing ends along the first straight line Dr: a first end 3e1 closer to the first end 3a and a second end 3e2 closer to the second end 3c, and has a first width Wr along the first straight line Dr between both ends 3e1 and 3e2.

[0054] Furthermore, the second end 3e2 of the notch 3e, which corresponds to the second end (the tip of the second end 2d) 3c of the anti-rotation plate 3, is an open end. In other words, the anti-rotation pin portion 31b, which is inserted into the notch 3e as an insertion portion, may come into contact with the anti-rotation plate 3 at the first end 3e1 of the notch 3e, but it cannot come into contact with the anti-rotation plate 3 at the second end 3e2 of the notch 3e, and can move in and out of the notch 3e, which is the insertion portion, through the second end 3e2.

[0055] On the other hand, the notch 3e has a third end 3e3 and a fourth end 3e4 as opposing ends along the second straight line Dt, and has a second width Wt between the ends 3e3 and 3e4 along the second straight line Dt. The second width Wt is larger than or equal to the width Wp of the anti-rotation pin portion 31b along the second straight line Dt, ensuring the minimum size necessary to allow the anti-rotation pin portion 31b to be inserted into the notch 3e, while keeping its size such that the anti-rotation pin portion 31b inserted into the notch 3e comes into contact with the anti-rotation plate 3 at at least one of the ends 3e3 and 3e4 of the notch 3e along the second straight line Dt, thereby restricting the relative movement of the anti-rotation plate 3 (integrated with the pivot 2) and the anti-rotation pin portion 31b (integrated with the boom 31) along the second straight line Dt (the rotational direction around the axis 2a of the pivot 2).

[0056] As a result, the boom 31, which is integrated with the anti-rotation pin portion 31b inserted into the notch 3e, is prevented from rotating relative to the pivot 2 via the anti-rotation plate 3 (its relative rotation is suppressed).

[0057] By making the size of this second width Wt approximately the same as the width of the anti-rotation pin portion 31b in the direction along the second straight line Dt, which is the minimum size necessary to insert the anti-rotation pin portion 31b into the notch 3e (if the anti-rotation pin portion 31b is configured to have the same diameter all around, then approximately the same size as the diameter (outer diameter) of the anti-rotation pin portion 31b), it is possible to most strictly restrict the relative movement between the anti-rotation plate 3 and the anti-rotation pin portion 31b in the direction along the second straight line Dt. In other words, in this case, the anti-rotation pin portion 31b inserted into the notch 3e abuts the anti-rotation plate 3 at both ends 3e3 and 3e4 in the direction along the second straight line Dt of the notch 3e, and there is no room within the notch 3e for the anti-rotation pin portion 31b to move relative to the anti-rotation plate 3 in the rotation direction of the pivot 2 which is approximately coincident with the direction along the second straight line Dt. Therefore, regardless of the direction of the relative swing between the boom 31 and the arm 32, the boom 31 and the pivot 2 always rotate together around the axis 2a of the pivot 2 without relative rotation.

[0058] Furthermore, if the size of the second width Wt is made slightly larger than the width of the anti-rotation pin portion 31b in the direction along the second straight line Dt, a small amount of clearance (play) is created within the notch 3e that allows the anti-rotation pin portion 31b to move relative to the anti-rotation plate 3 (pivot 2) in the direction along the second straight line Dt. When the anti-rotation pin portion 31b rotates relative to the anti-rotation plate 3 (pivot 2) by this amount of clearance, it will come into contact with the anti-rotation plate 3 at one of the two ends 3e3 and 3e4 of the notch 3e in the direction along the second straight line Dt, and its relative rotation will be restricted.

[0059] On the other hand, the first width Wr between the two ends 3e1 and 3e2 in the direction along the first straight line Dr of the notch 3e is such that the inserted anti-rotation pin portion 31b can be repositioned in the direction along the first straight line Dr. In other words, there is room (play) within the insertion portion of the notch 3e that allows the position of the anti-rotation pin portion 31b to be changed in the direction along the first straight line Dr.

[0060] As a result, even if there is an error in the dimensional setting regarding the distance between the shaft hole 31a and the anti-rotation pin portion 31b at the tip portion 31c of the boom 31, the anti-rotation pin portion 31b can be inserted into the notch 3e in the same state as if it had been positioned along the first straight line Dr.

[0061] For example, if the distance between the shaft hole 31a and the anti-rotation pin portion 31b at the tip portion 31c of the boom 31 is smaller than a reference value (average value, etc.), the anti-rotation pin portion 31b can be inserted into the notch 3e at a position closer to the first end 3e1, which is the inner end of the notch 3e, than the insertion position of the anti-rotation pin portion 31b when the distance is the reference value.

[0062] On the other hand, if the distance between the shaft hole 31a and the anti-rotation pin portion 31b is greater than a reference value (average value, etc.), it is possible to position a portion of the anti-rotation pin portion 31b outside the second end (open end) 3e2 of the notch 3e in the direction along the first straight line Dr, and to insert only the other portion of the anti-rotation pin portion 31b closer to the first end 3e1 into the notch 3e.

[0063] As described above, even if there is some dimensional error in the distance between the shaft hole 31a and the anti-rotation pin portion 31b in the direction along the first straight line Dr, the tip portion 31c of the boom 31 can be reliably inserted into the notch 3e, which is the insertion portion of the anti-rotation plate 3, and thus the anti-rotation pin portion 31b can be restricted by the anti-rotation plate 3 relative to the pivot 2 in the direction along the second straight line Dt.

[0064] Furthermore, the anti-rotation plate 3 shown in Figures 2 to 5 has a notch 3e with an opening (second end) 3e2 corresponding to the tip 3c of the anti-rotation plate 3, which is the insertion part for inserting the anti-rotation pin portion 31b. Therefore, among the dimensional errors regarding the distance between the shaft hole 31a at the tip 31c of the boom 31 and the anti-rotation pin portion 31b (hereinafter referred to as "the said distance"), the error that is greater than the reference value (average value, etc.) can be addressed by shifting the relative position of the anti-rotation pin portion 31b with respect to the anti-rotation plate 3 to the outward side (away from the pivot 2) of the opening 3e2 of the notch 3e.

[0065] Therefore, the first width Wr of the notch 3e in the direction along the first straight line Dr only needs to be set considering the smaller of the dimensional errors for the spacing in the boom 31 that is smaller than the reference value (average value, etc.), which can contribute to simplifying the design process of the notch (insertion part) 3e in the anti-rotation plate (anti-rotation member) 3.

[0066] In the above-described oscillating body pivot structure P, if the pivot 2 unexpectedly slides in the direction of the axis 2a within the shaft hole 31a, the anti-rotation plate 3 may move integrally with the pivot 2 in the direction of the axis 2a and detach from the anti-rotation pin portion 31b that was inserted into the notch 3e. To prevent such detachment of the anti-rotation plate 3 from the anti-rotation pin portion 31b, the oscillating body pivot structure P is provided with an anti-detachment plate 5 or the like.

[0067] Specifically, as shown in Figures 4A, 4B, and 5, a screw hole 31b1 is provided in the anti-rotation pin portion 31b. A bolt 4, which serves as a fastener, is screwed into the screw hole 31b1, as shown in Figures 2 and 3. The bolt 4 is inserted through the central hole of the disc-shaped retaining plate 5 before being screwed into the screw hole 31b1 (see Figure 7). In this way, the flange-shaped retaining plate 5 is sandwiched between the head of the bolt 4 screwed into the screw hole 31b1 and the end face (end) of the anti-rotation pin portion 31b.

[0068] In this manner, the retaining plate 5, which is fastened to the anti-rotation pin portion 31b with fasteners such as bolts 4, is positioned near the outside of the anti-rotation plate 3 or in contact with the anti-rotation plate 3, thereby restricting the movement of the anti-rotation plate 3 in the direction of the axis 2a of the pivot 2 and preventing the anti-rotation plate 3 from falling off the anti-rotation pin portion 31b. In other words, the retaining plate 5 is provided as a restricting member that restricts the movement of the anti-rotation plate 3 in the direction of the axis 2a of the pivot 2.

[0069] The disc-shaped retaining plate 5 shown in Figures 2 and 3 is an example of such a restricting member. The restricting member only needs to be configured to restrict the movement of the anti-rotation member in the direction of the axis 2a of the pivot 2, and as long as it is configured in this way, there are no restrictions in terms of shape, material, etc. Also, the fastener is not limited to a bolt 4, but may be a screw or the like.

[0070] Furthermore, as the anti-rotation member connecting the pivot 2 and the anti-rotation pin portion 31b, instead of the anti-rotation plate 3 having a notch 3e as an insertion portion as shown in Figures 2 to 5, an anti-rotation plate 3X having an elongated hole 3h as an insertion portion may be used, as shown in Figures 6A and 6B.

[0071] Figure 6A is a side view of the oscillating pivot structure P1(P) equipped with an anti-rotation member (anti-rotation plate 3X) according to another embodiment. Figure 6B is an enlarged side view of the oscillating pivot structure P1(P) equipped with an anti-rotation member (anti-rotation plate 3X) according to another embodiment.

[0072] The anti-rotation plate 3X shown in Figures 6A and 6B will now be described. The anti-rotation plate 3X has a base end (first end) 3a and a first end 3b common to the anti-rotation plate 3, and the first end 3b is positioned around the end of the pivot 2 and fixed to that end of the pivot 2.

[0073] On the other hand, the elongated hole 3h, which is the insertion part of the anti-rotation plate 3X, is closed at the tip (second end) 3f on the side opposite to the base end 3a. That is, including this tip 3f, the second end 3g of the anti-rotation plate 3X on the side opposite to the first end 3b is formed to surround (close) the elongated hole 3h around its entire circumference.

[0074] The configuration of the elongated hole 3h, which is the insertion part in the anti-rotation plate 3X shown in Figures 6A and 6B, can be defined as follows when applied to the configuration of the insertion part in the aforementioned oscillating pivot structure P. That is, referring to Figure 6B, the elongated hole 3h, which is an example of an insertion part, has a first width Wrx between both ends 3h1 and 3h2 in the direction of a virtual first straight line Dr that extends along a direction that coincides with one radial direction of the pivot 2 and passes through the first end 3b and the second end 3g, and a second width Wt between both ends 3h3 and 3h4 in the direction of a virtual second straight line Dtx that is perpendicular to the axis 2a of the pivot 2 and the first straight line Drx.

[0075] The elongated hole 3h is closed at both ends 3h1 and 3h2 along the first straight line Dr, and is an elongated hole that extends along the first straight line Drx (radial direction of the pivot 2). That is, the first width Wrx is larger than the second width Wtx, and the elongated hole 3h has a size that allows the inserted anti-rotation pin portion 31b to be repositioned along the first straight line Dr.

[0076] The second width Wtx is sized such that the anti-rotation pin portion 31b can be inserted into the elongated hole 3h, and the anti-rotation pin portion 31b inserted into the elongated hole 3h abuts against the anti-rotation plate 3 at at least one of the ends 3h3 and 3h4 of the elongated hole 3h in the direction along the second straight line Dtx, thereby restricting the relative movement of the anti-rotation plate 3 with respect to the anti-rotation pin portion 31b in the direction along the second straight line Dtx.

[0077] In particular, the elongated hole 3h in this anti-rotation plate 3X is configured such that, in terms of position and size (first width Wrx) along the first straight line Dr, the anti-rotation pin portion 31b is located approximately midway between the ends 3h1 and 3h2 when the distance at the tip portion 31c of the boom 31 (distance between the shaft hole 31a and the anti-rotation pin portion 31b) is a reference value (average value, etc.).

[0078] In other words, the first width Wrx of the elongated hole 3h in the direction along the first straight line Dr (radial direction of the pivot 2) is set such that both the error smaller than the reference value and the error larger than the reference value among the dimensional errors regarding the spacing in the boom 31 can be taken into consideration, and either error can be accommodated by adjusting the relative position of the anti-rotation pin portion 31b with respect to the anti-rotation plate 3X in the direction along the first straight line Dr within the elongated hole 3h.

[0079] More specifically, in the anti-rotation plate 3X according to this embodiment, whether the error in the spacing is smaller than the reference value or larger than the reference value, the anti-rotation pin portion 31b can be inserted into the elongated hole 3h having a second width Wtx in the direction along the second straight line Dt. Therefore, in either state, the anti-rotation action (an action that restricts the relative rotation between the pivot 2 and the boom 31) of the anti-rotation plate 3 (the second end portion 3g of the anti-rotation plate 3X provided on both sides of the elongated hole 3h in the direction along the second straight line Dt) is effectively applied to the anti-rotation pin portion 31b at both ends 3h3 and 3h4 of the elongated hole 3h.

[0080] In the anti-rotation plate 3 according to the above embodiment, the anti-rotation pin portion 31b with a dimensional error smaller than the reference value in the spacing is inserted into a notch 3e having a second width Wt in the direction along the second straight line Dt, and can effectively receive the anti-rotation action from the anti-rotation plate 3 (i.e., the action that restricts the relative rotation between the pivot 2 and the boom 31) at both ends 3e3 and 3e4 of the notch 3e. On the other hand, the anti-rotation pin portion 31b with a dimensional error larger than the reference value in the spacing is positioned to protrude outside the opening end (second end) 3e2 of the notch 3e (part of it is inserted into the notch 3e). Therefore, the anti-rotation action applied to the anti-rotation pin portion 31b from the anti-rotation plate 3 at both ends 3e3 and 3e4 of the notch 3e in the direction along the second straight line Dt (i.e., the action that restricts the relative rotation between the pivot 2 and the boom 31) may be reduced compared to the case where the anti-rotation pin portion 31b is inserted into the notch 3e in accordance with the error smaller than the reference value.

[0081] Even with such an anti-rotation plate 3, for example, by increasing the first width Wr in the direction along the first straight line Dr of the notch 3e, and configuring the anti-rotation pin portion 31b to be insertable into the notch 3e having a second width Wt in the direction along the second straight line Dt, even if there is a dimensional error in the interval that is larger than the reference value, such a reduction in the anti-rotation effect can be eliminated.

[0082] Although Figures 6A and 6B show the anti-rotation pin portion 31b with the retaining plate 5 removed (and the bolt 4 removed in Figure 6B), as in the previously described embodiment (see Figures 2 and 3), the bolt 4 may be inserted through the retaining plate 5 and then screwed into the threaded hole 31b1 of the anti-rotation pin portion 31b. The retaining plate 5, which is sandwiched between the head of the bolt 4 and the end face of the anti-rotation pin portion 31b, may be positioned near or in contact with the anti-rotation plate 3X to restrict the movement of the anti-rotation plate 3X in the direction of the axis 2a of the pivot 2.

[0083] Next, another embodiment of the oscillating body pivot structure P shown in Figure 7 will be described. This is a perspective view of the first oscillating body pivot structure P1 (a representative example of the oscillating body pivot structure P) equipped with an anti-rotation pin 6, which is another embodiment of the anti-rotation pin portion, and is a partially exploded view.

[0084] As described above, the anti-rotation pin portion of the oscillating body pivot structure P is a separate component from the main body portion of the first member, which is the oscillating body (in this embodiment, the tip portion 31c of the boom 31), and may be fastened to the main body portion of the first member with a fastener. The first oscillating body pivot structure P1 (oscillating body pivot structure P) shown in Figure 7 is equipped with an anti-rotation pin 6 as an example of such an anti-rotation pin portion.

[0085] The anti-rotation pin 6 is a cylindrical pin member separate from the main body (the tip portion 31c of the boom 31, etc.) and serves as the anti-rotation pin portion (the anti-rotation pin portion 31b of the boom 31, etc.) in the pivot structure P of the oscillating body.

[0086] The cylindrical anti-rotation pin 6 has a through hole in its inner circumference around its axis, and the inner surface facing this through hole is not a smooth surface, but has threads formed to form a female screw. In other words, this through hole is called a screw hole 6a. Thus, the anti-rotation pin 6 is a pin member having a screw hole 6a in its inner circumference that extends in the direction of the protrusion of the anti-rotation pin portion, which is substantially parallel to the axis 2a of the pivot 2.

[0087] Corresponding to this screw hole 6a, a screw hole 31f is provided in the tip portion 31c of the boom 31, which is the main body of the first member, and opens on the side surface of the tip portion 31c. The anti-rotation pin 6 is inserted into the insertion portion (notch 3e in this embodiment) of the anti-rotation plate 3 with its axial direction (the direction in which the screw hole 6a extends) approximately parallel to the axis 2a of the pivot 2, and is in contact with the side surface of the tip portion 31c of the boom 31, so that the screw hole 6a and the screw hole 31f of the boom 31 (tip portion 31c) are aligned, thereby positioning the pin relative to the tip portion 31c of the boom 31.

[0088] A bolt 4, which is a fastener, is screwed into the screw hole 6a of the anti-rotation pin 6, which is positioned in this manner, and into the screw hole 31f which is centered on the screw hole 6a. When the bolt 4 is screwed into the screw hole 31f of the tip portion 31c, the anti-rotation pin 6, which is sandwiched between the head of the bolt 4 and the side of the tip portion 31c, is tightened to the tip portion 31c of the boom 31.

[0089] Furthermore, within the screw hole 6a of the anti-rotation pin 6, the threads of the bolt 4 and the threads formed on the inner surface of the screw hole 6a engage. This integrates the anti-rotation pin 6 and the boom 31 via the bolt 4. In other words, the anti-rotation pin 6, with its inner surface forming a screw hole 6a, engages with the bolt 4 inserted through the screw hole 6a. This engagement makes it difficult for the anti-rotation pin 6 to move relative to the bolt 4 (in the axial direction and around the axial direction) compared to a simple boss with a smooth inner surface.

[0090] In this way, the anti-rotation pin 6, which is a pin member separate from the main body of the first member, is restricted from moving (separation from and detachment from the tip portion 31c) in the protruding direction (a direction substantially parallel to the axis 2a of the pivot 2) as the anti-rotation pin portion by the bolt 4, which is a fastener.

[0091] Furthermore, as shown in Figure 7, similar to the embodiments shown in Figures 2 and 3, the bolt 4 may be inserted through the retaining plate 5 and then screwed into the anti-rotation pin 6. The retaining plate 5, which is sandwiched between the head of the bolt 4 and the end face of the anti-rotation pin 6, may be positioned near or in contact with the anti-rotation plate 3 (or 3X) to restrict the movement of the anti-rotation plate 3 (3X) in the direction of the axis 2a of the pivot 2.

[0092] Next, we will explain the oscillating pivot structure P, some of the components (items) of the work machine 1 equipped with the oscillating pivot structure P, and the effects thereof.

[0093] (Item 1) The assembly comprises a pivot 2, a first member 31 and a second member 32 pivotally connected to each other via the pivot 2 so as to be able to swing relative to each other, and an anti-rotation member 3(3X) attached to the pivot 2, wherein the first member 31 has a main body portion 31c, an axial hole 31a provided in the main body portion 31c through which the pivot 2 is inserted, and an anti-rotation pin portion 31b(6) that protrudes from the main body portion 31c in a direction substantially parallel to the axis 2a of the pivot 2 near the axial hole 31a, The anti-rotation member 3(3X) has a first end 3b fixed to the pivot 2 and a second end 3d(3g) provided with an insertion portion 3e(3h) into which the anti-rotation pin portion 31b is inserted, and the insertion portion 3e(3h) has a first width Wr(Wrx) between both ends 3e1·3e2(3h1·3h2) in a direction along a virtual first straight line Dr that extends to pass through the first end 3b and the second end 3d(3g) in a direction that coincides with one radial direction of the pivot 2, and the The pivot 2 has a second width Wt (Wtx) between its two ends 3e3·3e4 (3h3·3h4) in the direction along a virtual second straight line Dt perpendicular to the axis 2a of the pivot 2 and the first straight line Dr, wherein the first width Wr (Wrx) is such that the inserted anti-rotation pin portion 31b (6) in the insertion portion 3e can be repositioned in the direction along the first straight line Dr, and the second width Wt (Wtx) is the width Wp of the anti-rotation pin portion 31b in the direction along the second straight line Dt. A pivot support structure P having the above dimensions, and having a size such that the anti-rotation pin portion 31b(6) inserted into the insertion portion 3e(3h) abuts against the anti-rotation member 3 at least one end of the two ends 3e3·3e4(3h3·3h4) of the insertion portion 3e(3h) in the direction along the second straight line Dt, thereby restricting the relative movement between the anti-rotation member 3(3X) and the anti-rotation pin portion 31b(6) in the direction along the second straight line Dt.

[0094] In a pivot support structure P with such a configuration, for example, if the positioning accuracy of the anti-rotation pin portion 31b in the main body portion 31c of the first member 31 is insufficient, and there is a dimensional error in the distance between the shaft hole 31a and the anti-rotation pin portion 31b in the first member 31, the insertion portion 3e(3h) has a first width Wr(Wrx) of sufficient size between both ends 3e1 and 3e2 in the direction along the first straight line Dr which substantially coincides with the radial direction of the pivot 2, so that rotation The retaining pin portion 31b(6) can be securely inserted into the insertion portion 3e(3h), and the rotation-restricting pin portion 31b(6) inserted into the insertion portion 3e(3h) in this manner can be reliably provided with a rotation-restricting effect (rotation-restricting of the first member 31 relative to the pivot 2) by the rotation-restricting member 3(3X) at both ends 3e3 and 3e4 of the insertion portion 3e(3h) in the direction along the second straight line Dt which substantially coincides with the rotation direction of the pivot 2.

[0095] (Item 2) The pivot support structure P according to Item 1, wherein the insertion portion 3e is a notch 3e that opens at one end 3e2 of the two ends 3e1 and 3e2 in the direction along the first straight line Dr, corresponding to the tip 3c of the second end 3d.

[0096] In a pivot support structure with this configuration, the anti-rotation pin portion 31b can be securely inserted into the insertion portion 3e, and the anti-rotation action of the anti-rotation member 3 can be reliably applied to the anti-rotation pin portion 31b at both ends in the second width direction of the insertion portion 3e.

[0097] (Item 3) The pivot support structure P according to Item 1, wherein the insertion portion 3h is closed at both ends 3h1 and 3h2 in the direction along the first straight line Dr, and the elongated hole 3h extends in the direction along the first straight line Dr.

[0098] In a pivot support structure with this configuration, the anti-rotation pin portion 31b can be securely inserted into the insertion portion 3h, and the anti-rotation action of the anti-rotation member 3 can be reliably applied to the anti-rotation pin portion 31b at both ends of the insertion portion 3h in the direction of the second width.

[0099] (Item 4) The pivot support structure P according to any one of Items 1 to 3, wherein the anti-rotation pin portion 31b is integrally molded together with the main body portion 31c by casting.

[0100] In a pivot support structure P with such a configuration, the insertion portion 3e(3h) of the anti-rotation member 3(3X) is configured to allow insertion of the anti-rotation pin portion 31b to accommodate dimensional errors in the distance between the shaft hole 31a and the anti-rotation pin portion 31b in the first member 31 that may occur during the casting process. Therefore, even if the positioning accuracy of the anti-rotation pin portion 31b in the first member 31 is insufficient, the pivot 2 and the anti-rotation pin portion 31b can be connected by the anti-rotation member 3(3X) to prevent the first member 31 from rotating (restricting the relative rotation of the pivot 2 and the first member 31).

[0101] (Item 5) The pivot support structure P described in any one of Items 1 to 3, wherein the anti-rotation pin portion 31b is integrated with the main body portion 31c by welding.

[0102] In a pivot support structure P with such a configuration, the insertion portion 3e(3h) of the anti-rotation member 3(3X) is configured to allow insertion of the anti-rotation pin portion 31b to accommodate dimensional errors in the distance between the shaft hole 31a and the anti-rotation pin portion 31b in the first member 31, which may occur due to inaccurate welding positions. Therefore, even if the positioning accuracy of the anti-rotation pin portion 31b in the first member 31 is insufficient, the pivot 2 and the anti-rotation pin portion 31b can be connected by the anti-rotation member 3(3X) to prevent the first member 31 from rotating (restricting the relative rotation of the pivot 2 and the first member 31).

[0103] (Item 6) The pivot support structure P according to any one of Items 1 to 3, comprising: a pin member 6, which serves as the anti-rotation pin portion and is a cylindrical member separate from the main body portion 31c, and which has a screw hole 6a on its inner circumference that extends in the direction of protrusion of the anti-rotation pin portion substantially parallel to the axis 2a of the pivot 2; and a fastener 4 for fastening the pin member 6 to the main body portion 31c, wherein the fastener 4 is screwed into the pin member 6 within the screw hole 6a, thereby restricting the movement of the pin member 6 in the protruding direction.

[0104] In a pivot support structure P with this configuration, the anti-rotation pin portion is a separate pin member 6 from the main body portion 31c of the first member 31. The main body portion 31c only needs to be provided with a screw hole 31f corresponding to the screw hole 6a of the pin member 6. This can contribute to simplifying the manufacturing process of the main body portion 31c of the first member 31, reducing weight, and lowering costs. Furthermore, the movement of the pin member 6 in the direction of the axis 2a of the pivot 2 is reliably restricted by the fastener 4, and the anti-rotation effect of the anti-rotation member 3 on the pivot 2 of the first member 31 can be maintained for a long time without the pin member 6 falling out.

[0105] (Item 7) The oscillating pivot structure P according to any one of Items 1 to 6, comprising: a fastener 4 that is screwed into a screw hole 31b1(6a) provided in the anti-rotation pin portion 31b(6); and a restricting member 5 that is sandwiched between the head of the fastener 4 screwed into the screw hole 31b1(6) and the end of the anti-rotation pin portion 31b(6) to restrict the movement of the anti-rotation member 3(3X) in the direction of the axis 2a of the pivot 2.

[0106] In a pivot support structure P with such a configuration, the pivot 2 may move in the direction of the axis 2a within the shaft hole 31a due to rattle, and as a result the anti-rotation member 3(3X) may move and come off the anti-rotation pin portion 31b(6). However, the regulating member 5, which is fastened to the anti-rotation pin portion 31b(6) by the fastener 4, is positioned near the anti-rotation member 3 or comes into contact with the anti-rotation member 3, thereby restricting the movement of the anti-rotation member 3 in the direction of the axis 2a of the pivot 2 and preventing the anti-rotation member 3 from coming off the anti-rotation pin portion 31b(6).

[0107] (Item 8) A work machine 1 comprising a machine body 20, a boom 31 swingably supported on the machine body 20, an arm 32 swingably supported on the boom 31, and a swinging pivot structure P1 according to any one of Items 1 to 7, provided as a pivot point for the boom 31 and the arm 32.

[0108] In a work machine 1 with such a configuration, the pivot point between the boom 31 and the arm 32 can be given a favorable effect by the oscillating pivot structure P1 having a configuration described in any of items 1 to 7.

[0109] (Item 9) A work machine 1 comprising a machine body 20, a work device 30 that is pivotably supported on the machine body 20, and a pivot support structure P2 according to any one of Items 1 to 7, which is provided as a pivot point between the machine body 20 and the work device 30.

[0110] In a work machine 1 with such a configuration, the pivot point between the machine body 20 (swing bracket 14) and the work device 30 (boom 31) can be provided with the desirable effects of a swinging pivot structure P2 having the configuration described in any of items 1 to 7.

[0111] (Item 10) A work machine 1 comprising a machine body 20, a work device 30 supported by the machine body 20, a work tool 33 swingably supported by the work device 30, and a swinging pivot structure P3 according to any one of Items 1 to 7, provided as a pivot point for the work device 30 and the work tool 33.

[0112] In a work machine 1 with such a configuration, a favorable effect can be exerted on the pivot point between the work device 30 (arm 32) and the work tool (bucket 33) by a swinging pivot structure P3 having a configuration described in any of items 1 to 7.

[0113] While embodiments of the present invention have been described above, the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope of equivalence to the claims are intended to be included. [Explanation of symbols]

[0114] 1. Work equipment (excavation equipment) 2 Axis 2a Axis core 3. Anti-rotation plate (anti-rotation member) 3X Anti-rotation plate (anti-rotation component) 3b First end 3c Tip (tip of the second end) 3d second end 3e Notch (insertion part) 3e1 1st end 3e2 2nd end (open end) 3e3 3rd end 3e4 4th end 3f Tip (tip of the second end) 3g 2nd end 3h elongated hole (insertion part) 3h1·3h2 Both ends 3h3·3h4 Both ends 4 bolts (fasteners) 5. Retaining plate (regulating member) 6. Anti-rotation pin (pin component) 6a Screw hole 14. Swing bracket (second component) 20 aircraft 30 Working equipment 31 Boom (First component) 31a Shaft hole 31b Anti-rotation pin section 31c Tip (main body of the first component) 31d Base end (main body of the first member) 32 Arm (Second Member) 33. Bucket (working tool, first component) P Swivel Body Pivot Structure P1 First pivot structure for the swinging body (pivot point for the boom and arm) P2 Second oscillating body pivot structure (pivot part connecting the machine body and work equipment) P3 Third oscillating pivot structure (pivot part of work device and work tool) Dr 1st straight line Dt 2nd straight line Wr 1st width Wrx 1st width Wt 2nd width Wtx 2nd width

Claims

1. The Axis and, A first member and a second member are pivotally connected to each other via the aforementioned pivot so as to be able to swing relative to each other, A rotation-preventing member attached to the pivot, Equipped with, The first member comprises a main body portion, a shaft hole provided in the main body portion through which the pivot is inserted, and an anti-rotation pin portion that protrudes from the main body portion in a direction substantially parallel to the axis of the pivot near the shaft hole. The anti-rotation member has a first end fixed to the pivot and a second end provided with an insertion portion into which the anti-rotation pin is inserted. The insertion portion has a first width between its ends in a direction along a virtual first straight line that extends to pass through the first and second ends and coincide with one radial direction of the pivot, and a second width between its ends in a direction along a virtual second straight line that is perpendicular to the axis of the pivot and the first straight line. The first width is such that the inserted anti-rotation pin portion can be repositioned in the direction along the first straight line within the insertion portion. The second width is greater than or equal to the width of the anti-rotation pin portion in the direction along the second straight line, and is large enough to restrict the relative movement between the anti-rotation member and the anti-rotation pin portion in the direction along the second straight line by the anti-rotation pin portion inserted into the insertion portion contacting the anti-rotation member at at least one end of the insertion portion in the direction along the second straight line.

2. The pivot support structure for a rocking body according to claim 1, wherein the insertion portion is a notch that opens at one end corresponding to the tip of the second end of the two ends in the direction along the first straight line.

3. The pivot support structure for a rocking body according to claim 1, wherein the insertion portion is closed at both ends in the direction along the first straight line and is an elongated hole extending along the direction along the first straight line.

4. The pivot support structure for a swing body according to claim 1, wherein the anti-rotation pin portion is integrally molded with the main body portion by casting.

5. The pivot support structure for a swinging body according to claim 1, wherein the anti-rotation pin portion is integrated with the main body portion by welding.

6. The aforementioned anti-rotation pin portion is a cylindrical member separate from the main body portion, and has a screw hole on its inner circumference that extends in the direction of the protrusion of the anti-rotation pin portion, substantially parallel to the axis of the pivot, A fastener for fastening the pin member to the main body, Equipped with, The pivot support structure for a swing body according to claim 1, wherein the fastener is screwed into the pin member within the screw hole, thereby restricting the movement of the pin member in the protruding direction.

7. A fastener that is screwed into a screw hole provided in the aforementioned anti-rotation pin portion, A restricting member is sandwiched between the head of the fastener screwed into the screw hole and the end of the anti-rotation pin portion, thereby restricting the movement of the anti-rotation member in the axial direction of the pivot, The oscillating body pivot structure according to claim 1, comprising:

8. The aircraft and, The boom of the aforementioned aircraft is supported so as to be swingable, An arm supported so as to be swingable on the aforementioned boom, A pivot structure for a swinging body according to any one of claims 1 to 7, provided as a pivot point for the boom and the arm, A work machine equipped with the following features.

9. The aircraft and, A working device that is pivotably supported on the aforementioned machine, A pivot support structure according to any one of claims 1 to 7, provided as a pivot point for the machine body and the work device, A work machine equipped with the following features.

10. The aircraft and, A work device supported by the aforementioned machine, A work tool that is pivotably supported by the aforementioned work device, A pivot support structure according to any one of claims 1 to 7, provided as a pivot part of the work device and the work tool, A work machine equipped with the following features.

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