Fixing structure of lock pin and tooth member equipped therewith

Abstract

A locking pin is provided that allows for easier fastening of the tooth member and the adapter. [Solution] The lock pin 10 comprises a body 11 having an engaging portion 12 that engages with the retainer 40, two support surfaces 14a and 14b formed on the opposite side of the body 11 from the engaging portion 12 and consisting of a first support surface 14a on the insertion front end side and a second support surface 14b on the insertion rear end side, a protrusion 15 formed on the body so as to be positioned between the two support surfaces 14a and 14b and protruding from the two support surfaces 14a and 14b, and a recess 16 positioned between the protrusion 15 and the second support surface 14b, capable of accommodating the second inner wall surface 36 before the second inner wall surface 36 is supported by the second support surface 14b.

Description

[[Technical Field]]

[0001] The present invention relates to a lock pin for fixing a tooth member to an adapter at a tip of a bucket of an excavator machine, and a fixing structure for a tooth member including the same. [[Background Art]]

[0002] A plurality of adapters are fixed at predetermined intervals to the tip of a bucket of an excavator machine, and various tooth members are respectively coupled to the adapters. The tooth member is an excavating tool such as a plate-shaped tooth plate or a wedge-shaped point tooth, for example. For example, Patent Document 1 describes that a lock pin and an elastic pin (retainer) holding the lock pin are used as a method for fixing a tooth member to an adapter.

[0003] Here, FIG. 11 is a cross-sectional view showing an arrangement relationship of a conventional lock pin, a tooth member and an adapter. As shown in FIG. 11, a first through hole 112 is formed through a protruding portion 111 of an adapter 110, and the retainer 120 is attached to the protruding portion 111 so as to be exposed within the first through hole 112. On the other hand, the tooth member 130 has a recessed portion 131, and a second through hole 134 is respectively formed through two opposing opposing portions 133 in the recessed portion 131. Then, in a state where the protruding portion 111 and the recessed portion 131 are fitted, the two second through holes 134 and the first through hole 112 communicate with each other to form an insertion hole 135 into which the lock pin 100 is inserted. In FIG. 11, the arrow Z indicates the insertion direction of the lock pin 100.

[0004] The protruding portion 111 of the adapter 110 has a first inner wall surface portion 113 facing the first through hole 112 and opposing the retainer 120. On the other hand, the tooth member 130 has two second inner wall surface portions 136 facing the second through holes 134, and the first inner wall surface portion 113 is arranged between the two second inner wall surface portions 136.

[0005] Furthermore, because the first inner wall surface portion 113 is positioned recessed (to the right in Figure 11) relative to the two second inner wall surface portions 136, the first inner wall surface portion 113 and the two second inner wall surface portions 136 are arranged in a stepped manner. Thus, the portion of the second inner wall surface portion 136 adjacent to the first inner wall surface portion 113 forms a stepped portion 140 relative to the first inner wall surface portion 113. This stepped configuration of the first inner wall surface portion 113 and the second inner wall surface portions 136 makes it easier to insert the tip of the lock pin 100 into the insertion hole 135 during the initial stages of insertion of the lock pin 100.

[0006] Furthermore, as the lock pin 100, which has been driven into the insertion hole 135, receives a reaction force from the retainer 120, and the tip of the lock pin 100 overcomes the lower step portion 140 in Figure 11, the engaging portion 101 of the lock pin 100 and the engaging portion 121 of the retainer 120 engage, and the support surface 102 on the opposite side of the engaging portion 101 of the lock pin 100 supports the two second inner wall portions 136. In this state, the tooth member 130 and the adapter 110 are fixed by the lock pin 100. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2016-089412 [Overview of the project] [Problems that the invention aims to solve]

[0008] Incidentally, in recent years, tooth components and adapters have been supplied to the market in many different product types. However, these products have problems such as incompatibility between products from different manufacturers, and large manufacturing tolerances even when manufactured by the same company. Therefore, depending on the combination of tooth components and adapters, it may not be possible to secure them using conventional locking pins.

[0009] Here, Figure 12 shows the arrangement relationship of the conventional lock pin, tooth member, and adapter, similar to Figure 11. As mentioned above, due to inconsistencies between products and manufacturing errors, the step S between the first inner wall surface 113 and the second inner wall surface 136 may be relatively large. Here, the step S is the gap between the plane H passing through the two second inner wall surfaces 136 and the plane L passing through the first inner wall surface 23.

[0010] Thus, when the step S is relatively large, as shown in Figure 12, the tip of the lock pin 100 receives a reaction force from the retainer 120 and becomes deeply embedded in the step S, causing the tip of the lock pin 100 to catch on the step portion 140 and preventing it from overcoming the step portion 140. As a result, it becomes difficult to fix the tooth member 130 and the adapter 110 with the lock pin 100.

[0011] The present invention has been made in view of the above, and its objective is to provide a locking pin that can easily fix a tooth member and an adapter. [Means for solving the problem]

[0012] The lock pin according to the present invention is an adapter provided at the tip of a bucket in an excavator, and is a lock pin for connecting and fixing an adapter having a projection with a first through-hole formed through it, and a retainer attached to the projection so as to protrude within the first through-hole, and a tooth member having a recess that fits into the projection, and two second through-holes formed that each penetrate two opposing portions of the recess. The lock pin is configured to connect and fix the adapter and the tooth member by being inserted into a through-hole formed by the two second through-holes communicating with the first through-hole while the projection and the recess are fitted together, and by engaging with the retainer. The protruding portion has a first inner wall surface facing the first through hole and facing the retainer, and the tooth member has two second inner wall surfaces facing the second through hole, with the first inner wall surface positioned between the two second inner wall surfaces, and the first inner wall surface positioned recessed relative to the two second inner wall surfaces, so that the portion of the second inner wall surface adjacent to the first inner wall surface is a stepped portion relative to the first inner wall surface.

[0013] The lock pin comprises a main body having an engagement portion that engages with the retainer, and two support surfaces formed on the opposite side of the main body from the engagement portion, which individually support the second inner wall surface while the tooth member and the adapter are connected and fixed, the two support surfaces being composed of a first support surface located on the front end side in the insertion direction of the main body and a second support surface located on the rear end side in the insertion direction of the main body, and positioned between the two support surfaces. Furthermore, it is positioned only towards the tip side in the insertion direction of the main body, rather than at the central position in the insertion direction of the main body. a protrusion formed on the main body so as to protrude from the two support surfaces, the protrusion being configured to abut against the first inner wall surface when the main body is inserted into the through hole, and a part disposed between the protrusion and the second support surface. and is also positioned adjacent to the second support surface. The body comprises a recess formed to be lower than the two support surfaces, and configured to accommodate the second inner wall surface before it is supported by the second support surfaces when the body is inserted into the through hole.

[0014] In the above configuration, when the body of the lock pin is initially inserted into the through hole, the tip of the body in the insertion direction contacts the retainer protruding within the first through hole (i.e., within the insertion hole), and is pressed against the first inner wall surface by the reaction force from the retainer. However, since the protrusion of the body protrudes more than the two support surfaces, the protrusion acts as a fulcrum by contacting the first inner wall surface, thereby separating the first support surface on the tip side of the body from the first inner wall surface.

[0015] Furthermore, before the second support surface on the rear end side in the insertion direction of the main body supports the second inner wall surface of the tooth member (i.e., before the tip of the main body reaches the stepped portion), the second inner wall surface is accommodated in the recess of the main body. As a result, the first support surface on the tip side of the main body can be separated even further from the first inner wall surface, with the convex portion acting as a fulcrum.

[0016] In addition, by housing the second inner wall surface in the recess, the reaction force received by the main body from the retainer is reduced, increasing the degree of freedom of the main body's orientation, and allowing the main body's orientation to be brought closer to that of the insertion hole. Therefore, it becomes possible to easily insert the main body deeply into the insertion hole.

[0017] As described above, the first support surface of the main body can be separated significantly from the first inner wall surface, while the main body can be easily and deeply inserted into the insertion hole. This makes it easier for the first support surface of the main body to overcome the step difference with respect to the first inner wall surface, and thus the tooth member and the adapter can be easily fixed together. 。

[0018] The aforementioned protrusion is arranged adjacent to the first support surface. Ruko This is preferable.

[0019] According to the above configuration, when the lock pin is inserted, the protrusion abuts against the stepped portion at the mounting position where the two support surfaces individually support the second inner wall surface. This allows the lock pin to be fixed in place at the mounting position, preventing it from falling out.

[0020] Preferably, the main body has a flat surface that is positioned between the recess and the protrusion and is formed alongside the first and second support surfaces. This ensures the rigidity of the main body even while having a recess.

[0021] Further, the tooth member fixing structure according to the present invention includes an adapter provided at a tip end of a bucket in an excavator machine, a tooth member fitted to the adapter, and the lock pin for connecting and fixing the adapter and the tooth member. [Advantageous Effects of Invention]

[0022] According to the present invention, the tip portion of the main body easily climbs over the stepped portion in the insertion hole formed in the mutually fitted tooth member and the adapter, so that the tooth member and the adapter can be easily fixed. [Brief Description of Drawings]

[0023] [Figure 1] Figure 1 is a perspective view showing a bucket of an excavator machine according to the present embodiment. [Figure 2] Figure 2 is a perspective view showing an adapter and a tooth member immediately before they are fitted to each other. [Figure 3] Figure 3 is a perspective view showing the lock pin, and the adapter and the tooth member fitted to each other according to the present embodiment. [Figure 4] Figure 4 is a cross-sectional view showing a main part of the adapter and the tooth member fitted to each other. [Figure 5] Figure 5 is a plan view schematically showing a first through hole and a second through hole constituting an insertion hole. [Figure 6] Figure 6 is a side view showing the outer shape of the lock pin. [Figure 7] Figure 7 is a cross-sectional view showing the adapter and the tooth member with the tip end side of the lock pin inserted therein. [Figure 8] Figure 8 is a cross-sectional view of the adapter and the tooth member showing a state where the tip portion of the lock pin approaches the stepped portion. [Figure 9] Figure 9 is a cross-sectional view of the adapter and the tooth member showing a state where the recessed portion of the lock pin accommodates the second inner wall surface portion. [Figure 10] Figure 10 is a cross-sectional view showing the fixing structure of the tooth member by the lock pin. [Figure 11]Figure 11 is a cross-sectional view showing an adapter and tooth member into which the tip of a conventional locking pin is inserted. [Figure 12] Figure 12 is a cross-sectional view of the adapter and tooth member showing the state in which the tip of a conventional locking pin is caught on the stepped portion. [Modes for carrying out the invention]

[0024] Embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to the following embodiments.

[0025] Figure 1 is a perspective view showing the bucket 5 of an excavator (not shown). Figure 2 is a perspective view showing the adapter 20 and tooth member 30 just before they are fitted together. Figure 3 is a perspective view showing the lock pin 10 and the fitted adapter 20 and tooth member 30 in this embodiment. Figure 4 is a cross-sectional view showing the main parts of the fitted adapter 20 and tooth member 30.

[0026] As shown in Figure 1, multiple adapters 20 are provided at predetermined intervals on the tip of the bucket 5 of the excavator. As shown in Figures 1 to 3, the base end of the adapter 20 is fixed to the tip portion of the bucket 5 by welding, with the base end sandwiching the plate-shaped tip portion of the bucket 5. On the other hand, as shown in Figures 2 and 4, a protrusion 21 is formed on the tip side of the adapter 20.

[0027] In the following explanation, the tip end of the adapter 20 (for example, the left side in Figure 4) may be referred to as the "front," and the base end end of the adapter 20 (for example, the right side in Figure 4) may be referred to as the "rear." Also, the tip portion A of the lock pin 10 in the insertion direction Z may be simply referred to as tip portion A.

[0028] As shown in Figures 2 and 4, a first through-hole 22 is formed through the protruding portion 21. The first through-hole 22 extends in a direction intersecting the protruding direction (forward) of the protruding portion 21, for example, extending in the vertical direction in Figure 4. A retainer (holding member) 40 is attached to the protruding portion 21 so as to be exposed within the first through-hole 22. For example, the retainer 40 is positioned in front of the first through-hole 22.

[0029] The tooth member 30 is a drilling tool such as a plate-shaped tooth plate or a wedge-shaped point tooth. Figures 1 to 3 show a point tooth type tooth member 30 as an example. The tip end of the tooth member 30 is a cutting edge 31, and as shown in Figure 4, a recessed portion 32 is formed at the base end of the tooth member 30 into which the protruding portion 21 of the adapter 20 fits.

[0030] The tooth member 30 has two opposing portions 33 that face each other in the recessed portion 32. A second through-hole 34 is formed through each of the opposing portions 33. The two second through-holes 34 are arranged coaxially and extend in the vertical direction, for example, in Figure 4.

[0031] Then, the two second through holes 34 and the first through hole 22, with the protruding portion 21 and the recessed portion 32 fitted together, communicate with each other to form an insertion hole 35. The lock pin 10 will be inserted into this insertion hole 35.

[0032] Here, Figure 5 is a schematic plan view showing the first through hole 22 and the second through hole 34 that constitute the insertion hole 35. As shown in Figures 4 and 5, the protruding portion 21 of the adapter 20 has a first inner wall surface portion 23 that faces the first through hole 22 and is opposite to the retainer 40. The first inner wall surface portion 23 is a part of the inner wall surface that demarcates the first through hole 22 and is an inner wall surface portion located on the rear side of the first through hole 22.

[0033] On the other hand, the tooth member 30 has a second inner wall surface portion 36, which is part of the inner wall surface facing the second through hole 34. The second inner wall surface portion 36 is an inner wall surface portion located on the rear side of the second through hole 34, and is located in each of the two second through holes 34. The first inner wall surface portion 23 is located between these two second inner wall surface portions 36. In other words, the two second inner wall surface portions 36 are located on both sides (upper and lower sides in Figure 4) of the first inner wall surface portion 23 in the direction in which the insertion hole 35 extends.

[0034] As shown in Figures 4 and 5, the first inner wall surface 23 is positioned recessed (to the right in Figure 4) relative to the two second inner wall surfaces 36, so that the first inner wall surface 23 and the two second inner wall surfaces 36 are arranged in a stepped manner. That is, the first inner wall surface 23 and the two second inner wall surfaces 36 form a concave stepped surface. Thus, a relatively large gap S is created between the plane H passing through the two second inner wall surfaces 136 and the plane L passing through the first inner wall surface 23.

[0035] The portion of the second inner wall surface 36 adjacent to the first inner wall surface 23 is a stepped portion 38 relative to the first inner wall surface 23. The gap S is the height of the stepped portion 38. Because the first inner wall surface 23 and the second inner wall surface 36 have a concave stepped configuration, even if the retainer 40 protrudes in the insertion hole 35, it becomes easier to insert the tip portion A of the lock pin 10 into the insertion hole 35 in the initial stages of insertion of the lock pin 10.

[0036] The retainer 40 has an elastic portion 41 made of an elastic resin material such as hard rubber, and a plurality of rigid portions 42 held by the elastic portion 41. The rigid portions 42 can be made of, for example, a cylindrical metal material. The axial direction of the rigid portions 42 is perpendicular to the axial direction of the first through hole 22. The plurality of rigid portions 42 are arranged at predetermined intervals and are embedded in the elastic portion 41 with a portion of each exposed.

[0037] The rigid body portion 42 exposed from the elastic portion 41 constitutes the engaging portion 43 of the retainer 40 that engages with the lock pin 10. As shown in Figure 4, the engaging portion 43 has multiple arc-shaped cross-sections. The elastic resin material that constitutes the elastic portion 41 is embedded and solidified inside the cylindrical rigid body portion 42. As a result, the rigid body portion 42 and the elastic portion 41 are integrated.

[0038] Here, Figure 6 is a side view showing the external shape of the lock pin 10. Figures 7 to 9 are cross-sectional views showing the adapter 20 and tooth member 30 into which the lock pin 10 is inserted. Figure 10 is a cross-sectional view showing the fixing structure of the tooth member 30 by the lock pin 10. The lock pin 10 is inserted into the through hole 35 and is held in place by engaging with the retainer 40, thereby connecting and fixing the adapter 20 and the tooth member 30.

[0039] As shown in Figure 6, the lock pin 10 has a body 11 made of a metal or the like. The body 11 has an engaging portion 12 that engages with the retainer 40. The engaging portion 12 has multiple arc-shaped cross-sections corresponding to the engaging portion 43 of the retainer 40. An arrow-shaped indicator 13 is formed on the side surface of the body 11 to indicate the insertion direction of the lock pin 10.

[0040] On the side of the main body 11 opposite the engaging portion 12, two support surfaces 14a and 14b are formed. The two support surfaces 14a and 14b consist of a first support surface 14a located on the front end side in the insertion direction Z of the main body 11, and a second support surface 14b located on the rear end side in the insertion direction of the main body 11. As shown in Figure 6, the two support surfaces 14a and 14b are arranged to be aligned along a predetermined reference plane M. In addition, a chamfered portion 18 is formed adjacent to the first support surface 14a on the front end portion A of the main body 11. By providing the chamfered portion 18, the front end of the main body 11 can more easily overcome the stepped portion 38.

[0041] As shown in Figure 10, with the tooth member 30 and the adapter 20 connected and fixed by the lock pin 10, the two support surfaces 14a and 14b are configured to individually support the second inner wall surface 36 of the tooth member 30.

[0042] The main body 11 has a projection 15 that protrudes from two support surfaces 14a and 14b (i.e., from the reference surface M). The projection 15 is positioned between the two support surfaces 14a and 14b. The projection 15 is not positioned at the center of the main body 11 in the insertion direction Z, but rather towards the tip of the main body 11 in the insertion direction Z. For example, the projection 15 is positioned adjacent to the first support surface 14a. In this way, the projection 15 is configured to prevent the main body 10 from falling off the tooth member 30 and adapter 20 to which it is connected and fixed.

[0043] The protrusion 15 is made of a metal material and is integrally formed with the main body 11, and protrudes from the reference surface M on the side opposite to the engaging portion 12. As will be described later, the protrusion 15 is configured to abut against the first inner wall surface 23 when the main body 11 is inserted into the insertion hole 35, as shown in Figures 8 and 9. By the protrusion 15 abutting against the first inner wall surface 23, the first support surface 14a on the tip side of the main body 11 can be separated from the first inner wall surface 23.

[0044] Furthermore, the main body 11 includes a recess 16 positioned between the protrusion 15 and the second support surface 14b. The recess 16 is formed to be recessed more than the two support surfaces 14a and 14b. In other words, the recess 16 is recessed relative to the reference surface M. The recess 16 is positioned adjacent to the second support surface 14b.

[0045] As will be described later, the recess 16 is configured to accommodate the second inner wall surface 36 of the tooth member 30 before it is supported by the second support surface 14b when the main body 11 is inserted into the through hole 35, as shown in Figure 9.

[0046] Furthermore, the main body 11 has a flat portion 17 positioned between the recess 16 and the protrusion 15. The flat portion 17 is formed alongside the first support surface 14a and the second support surface 14b (i.e., along the reference plane M). Alternatively, the flat portion 17 may be omitted, and the protrusion 15 and the recess 16 may be adjacent to each other.

[0047] Next, the method for fixing the adapter 20 and the tooth member 30 will be described. First, attach the retainer 40 to the protruding portion 21 of the adapter 20. Attach the retainer 40 to the front side of the first through-hole 22 in the protruding portion 21, causing the engaging portion 43 of the retainer 40 to protrude within the first through-hole 22. Next, as shown in Figures 2 to 4, fit the recessed portion 32 of the tooth member 30 with the protruding portion 21 of the adapter 20.

[0048] At this time, the first through hole 22 of the adapter 20 and the two second through holes 34 of the tooth member 30 are in communication, and the insertion hole 35 is formed by the first through hole 22 and the two second through holes 34. On the rear inner wall of the insertion hole 35, a stepped surface is formed in which the first inner wall surface portion 23 is set back relative to the two second inner wall surface portions 36. On the other hand, the engaging portion 43 of the retainer 40 is positioned facing the first inner wall surface portion 23 and protrudes rearward within the insertion hole 35.

[0049] Next, with the tip portion A of the main body 11 inserted into the insertion hole 35, the lock pin 10 is driven into the insertion hole 35 using a hammer (not shown) or the like. First, as shown in Figure 7, when the lock pin 10 is initially inserted, the tip portion A of the main body 11 comes into contact with the retainer 40 protruding in the insertion hole 35, and is biased by an elastic reaction force F0 received from the elastic portion 41 of the retainer 40 via the rigid portion 42, and is pressed towards the first inner wall surface portion 23. However, since the protrusion 15 of the main body 11 protrudes more than the two support surfaces 14a and 14b, the protrusion 15 acts to contact the first inner wall surface 23 and act as a fulcrum P, thereby gradually separating the first support surface 14a on the tip side of the main body 11 from the first inner wall surface 23. At this time, the flat surface 17 of the main body 11 is in contact with the upper second inner wall surface 36 in Figure 7.

[0050] Furthermore, when the lock pin 10 is inserted into the insertion hole 35, the second inner wall surface portion 36 of the tooth member 30 is housed in the recess 16 of the main body 11, as shown in Figure 8. At this time, the protrusion 15 acts as a fulcrum P, while the main body 11 receives an elastic reaction force F1 from the retainer 40. In this way, as the second inner wall surface portion 36 is housed in the recess 16, the first support surface portion 14a on the tip side of the main body 11 is separated even more significantly from the first inner wall surface portion 23 in the direction of arrow D, with the protrusion 15 acting as a fulcrum P.

[0051] Furthermore, at this time, as the second inner wall portion 36 is housed in the recess 16, the elastic reaction force F1 that the main body 11 receives from the retainer 40 is reduced, increasing the degree of freedom of the main body 11's orientation. As a result, the orientation of the main body 11 (i.e., the orientation of the lock pin 10) gradually changes to approach the axial direction of the insertion hole 35 (i.e., the insertion direction Z). This makes it easier to insert the main body 11 deeper into the insertion hole 35.

[0052] Next, as shown in Figure 9, when the lock pin 10 is further inserted and the tip portion A of the main body 11 approaches the stepped portion 38, a part of the engaging portion 43 of the retainer 40 engages with a part of the engaging portion 12 of the main body 11. That is, for example, the two upper of the three rigid portions 42 of the retainer 40 fit into and engage with the engaging portion 12 of the main body 11. This intermediate engagement state further reduces the elastic force F2 that the main body 11 receives from the retainer 40, and also allows the position of the lock pin 10 during insertion to be stably maintained. Furthermore, even in this state, the first support surface portion 14a at the tip of the main body 11 is significantly separated from the first inner wall surface portion 23 in the direction of arrow D, with the convex portion 15 acting as a fulcrum P.

[0053] As explained with reference to Figures 8 and 9, by housing the second inner wall portion 36 in the recess 16, the elastic reaction forces F1 and F2 that the main body portion 11 receives from the retainer 40 can be reduced. This reduction in elastic reaction forces F1 and F2 ensures sufficient freedom of movement for the orientation of the main body portion 11 to seat the first support surface portion 14a and the second support surface portion 14b on the second inner wall portion 36, improving the insertability of the lock pin 10, and also reduces the load on the retainer 40, thereby suppressing separation between the rigid body portion 42 and the elastic portion 41.

[0054] Next, as shown in Figure 10, by further driving the lock pin 10 into the insertion hole 35, the chamfered portion 18 and the first support surface portion 14a of the main body 11 overcome the stepped portion 38. In this way, the first support surface portion 14a and the second support surface portion 14b of the main body 11 ride up onto the second inner wall surface portion 36 of the tooth member 30, respectively, and support the second inner wall surface portion 36. In this way, at the mounting position of the lock pin 10 (see Figure 10) where the two support surfaces 14a and 14b individually support the second inner wall surface portion, the side surface of the protrusion 15 abuts against the stepped portion 38. As a result, the lock pin 10 is fixed in the mounting position, and the lock pin 10 (main body 11) is prevented from falling out of the tooth member 30 and adapter 20 in a connected and fixed state. At this time, the engaging portion 12 of the main body 11 completes its engagement with the engaging portion 43 of the retainer 40.

[0055] In this way, the main body 11 receives an elastic reaction force from the retainer 40 at the front and a pressing force from the two second inner wall surfaces 36 at the rear, thereby connecting and fixing the tooth member 30 and the adapter 20 by the lock pin 10.

[0056] As described above, according to this embodiment, as shown in Figure 7, when the main body 11 of the lock pin 10 is initially inserted into the insertion hole 35, the tip portion A of the main body 11 comes into contact with the retainer 40 protruding in the first through hole 22 (i.e., in the insertion hole 35), and is pressed toward the first inner wall surface portion 23 by the elastic reaction force F0 from the retainer 40. However, since the protrusion 15 of the main body 11 protrudes more than the two support surfaces 14a and 14b (i.e., more than the reference surface M), the protrusion 15 comes into contact with the first inner wall surface portion 23 and acts as a fulcrum P, thereby gradually separating the first support surface portion 14a on the tip side of the main body 11 from the first inner wall surface portion 23.

[0057] Furthermore, as shown in Figures 8 and 9, the second support surface portion 14b on the rear end side of the main body 11 in the insertion direction Z supports the second inner wall surface portion 36 of the tooth member 30 (i.e., before the tip portion A of the main body 11 reaches the stepped portion 38), so that the second inner wall surface portion 36 is accommodated in the recess 16 of the main body 11. This allows the first support surface portion 14a on the tip side of the main body 11 to be separated even more significantly from the first inner wall surface portion 23, with the convex portion 15 as the fulcrum P.

[0058] In addition, by housing the second inner wall portion 36 in the recess, the elastic reaction forces F1 and F2 that the main body 11 receives from the retainer 40 are reduced, increasing the degree of freedom of the orientation of the main body 11, and allowing the orientation of the main body 11 to be brought closer to the orientation along the insertion hole 35. Therefore, the main body 11 can be easily and deeply inserted into the insertion hole 35.

[0059] Thus, according to this embodiment, the main body 11 can be easily and deeply inserted into the insertion hole 35 while keeping the first support surface portion 14a of the main body 11 far away from the first inner wall surface portion 23. Therefore, the first support surface portion 14a of the main body 11 can easily overcome the step portion 38 relative to the first inner wall surface portion 23, and the tip portion A of the main body 11 can be prevented from getting caught on the step portion 38, allowing the tooth member 30 and the adapter 20 to be easily fixed together.

[0060] Furthermore, as shown in Figure 6, since the protrusion 15 is positioned towards the tip of the main body 11 rather than towards the center in the insertion direction Z, the position of the pivot point P by the protrusion 15 can be appropriately adjusted, allowing the tip portion A of the main body 11 to be more preferably separated from the first inner wall surface portion 23.

[0061] Furthermore, since the protrusion 15 is positioned adjacent to the first support surface 14a, when inserting the lock pin, the protrusion 15 abuts against the stepped portion 38 at the mounting position of the lock pin 10, thereby fixing the lock pin 10 in place. In addition, it is possible to prevent the lock pin 10 from falling downward beyond its mounting position, not only when inserting the lock pin 10, but also when using the tooth member 30 during work with a shovel machine.

[0062] Furthermore, as shown in Figure 6, a flat portion 17 is provided between the recess 16 and the protrusion 15 in the main body 11, and this flat portion 17 is formed to be aligned with the first support surface portion 14a and the second support surface portion 14b. This makes it possible to ensure sufficient rigidity of the main body 11 even while forming the recess 16 in the main body 11.

[0063] In addition, since the second inner wall portion 36 is housed in the recess 16, the elastic reaction forces F1 and F2 that the main body portion 11 receives from the retainer 40 can be reduced, thereby ensuring sufficient freedom of movement for the main body portion 11 and reducing the load on the retainer 40, which also helps to suppress separation between the rigid body portion 42 and the elastic portion 41. [Industrial applicability]

[0064] As described above, the present invention is useful for a locking pin for fixing a tooth member to an adapter at the tip of a shovel bucket, and for a fixing structure for a tooth member equipped with the same. [Explanation of Symbols]

[0065] 5 buckets 10 lock pins 11 Main unit 12 Engaging part 14a First Support Face 14b Second Support Face 15 convex part 16 recess 17. Central Plane Section 20 アダプタ 21. Protrusion 22 First through hole 23 First inner wall face 30 ツースComponents 32 concave part 33 Opposite Part 34 Second Through Hole 35 through holes 36 Second inner wall face 38 step difference department 40 リテーナ 43. Department of Integration

Claims

1. An adapter provided at the tip of the bucket of an excavator, having a projection with a first through-hole formed through it, and a retainer attached to the projection so as to protrude within the first through-hole, A lock pin for connecting and fixing a tooth member having a recess that fits into the protruding portion, and having two second through holes formed that penetrate two opposing portions of the recess, With the protruding portion and the recessed portion fitted together, the adapter is inserted into the through-hole formed by the communication of the two second through-holes and the first through-hole, and is configured to connect and fix the adapter and the tooth member by engaging with the retainer. The protruding portion has a first inner wall surface portion that faces the first through hole and is opposite to the retainer. The tooth member has two second inner wall surfaces facing the second through hole, and the first inner wall surface is positioned between the two second inner wall surfaces. Because the first inner wall surface is positioned recessed relative to the two second inner wall surfaces, the portion of the second inner wall surface adjacent to the first inner wall surface becomes a stepped portion relative to the first inner wall surface. A main body having an engaging portion that engages with the retainer, Two support surfaces formed on the opposite side of the engagement portion of the main body, which individually support the second inner wall surface portion while the tooth member and the adapter are connected and fixed, comprising a first support surface portion located on the front end side in the insertion direction of the main body, and a second support surface portion located on the rear end side in the insertion direction of the main body, A protrusion is positioned between the two support surfaces and formed on the main body so as to protrude from the two support surfaces, and is configured to contact the first inner wall surface when the main body is inserted into the through hole, A lock pin comprising a recess positioned between the convex portion and the second support surface portion, which is recessed more deeply than the two support surface portions, and which is configured to accommodate the second inner wall surface portion before it is supported by the second support surface portion when the main body is inserted into the through hole.

2. The lock pin according to claim 1, wherein the protrusion is positioned closer to the tip in the insertion direction of the main body than to the central position in the insertion direction of the main body.

3. The lock pin according to claim 2, wherein the protrusion is positioned adjacent to the first support surface to prevent the main body from falling off the tooth member and the adapter to which they are connected and fixed.

4. The lock pin according to claim 1, wherein the main body is disposed between the recess and the protrusion and has a flat portion formed alongside the first support surface and the second support surface.

5. An adapter attached to the tip of the bucket in an excavator, A tooth member that fits into the aforementioned adapter, A fixing structure for a tooth member, comprising the adapter and the lock pin according to claim 1 for connecting and fixing the tooth member.

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