Chen

Abstract

To provide a chain that is able to prevent with ease and at a low cost a reduction in the life of a chain that may be caused by wear of a link plate, without changing the structure of the link plate.SOLUTION: In a chain 24 formed by connecting a plurality of links 26, 28, the links 26, 28 respectively include a pair of link plates 26a, 28a, and a bush 26b or pin 29 connecting respective ends of each of the pair of link plates 28a, 26a in a length direction. A protection block member 32 with a link protection part 32 for protecting each link plate 28a is provided at one end of the link plate 28a, and the protection block member 32 is attached to the link plate 28a by means of the pin 29.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a chain used in a conveying device for conveying hard objects such as minerals. [Background technology]

[0002] A known transport device used to transport hard objects such as minerals from a collection point to another location is one that has a box-shaped body called a bucket attached to a rotating chain.By driving the chain, the object is scooped up in the bucket and transported along the chain's travel path.

[0003] 15 to 18 are diagrams to be referred to in order to explain such a conveying device 2 and conventional chains 4 and 14 used in the conveying device 2. FIG.

[0004] As shown in Figure 15, the conveying device 2 is endlessly wound around a number of sprocket wheels (not shown), and in part of its traveling path, it is equipped with two chains 4 arranged approximately parallel to each other at a predetermined distance in the vertical direction in the figure between sprocket wheels (not shown) that are arranged separately in the left-right direction in the figure, and a number of buckets 3 arranged at a predetermined distance in the traveling direction S of the chains 4 between these two chains 4, and each end of the buckets in the width direction (vertical direction in the figure) is connected to each chain 4 via an attachment 5.

[0005] As shown in Figure 16, the bucket 3 is formed in a roughly box-like shape with an opening 3a at the front side (left side in the figure) in the traveling direction S of the chains 4, and in part of the traveling path of the chains 4 of the conveying device 2, the bucket 3 body and its opening 3a are positioned between two chains 4 so that they are located below (lower side in the figure) of the chains 4 traveling in the traveling direction S.

[0006] A conventional chain 4 used in such a conveying device 2 includes a plurality of links (roller links 6 and pin links 8), as shown in FIG. 17, and is formed by connecting these roller links 6 and pin links 8 alternately.

[0007] As shown in Figure 17(a), the roller link 6 is provided with a pair of link plates 6a, each formed in a long, thin plate shape and arranged approximately parallel to each other at a predetermined distance so that their plate surfaces face each other, two cylindrical bushings 6b provided between the pair of link plates 6a to connect each end of each link plate 6a in the longitudinal direction (left and right direction in the figure), and two cylindrical rollers 7 provided on each bushing 6b so that they can rotate around their axis, with each bushing 6b as the rotation axis.

[0008] As shown in FIG. 17(a), the pin link 8 includes a pair of link plates 8a, each formed as a long, thin plate and arranged substantially parallel to each other at a predetermined distance so that their plate surfaces face each other, and two round bar-shaped pins 9 arranged between the pair of link plates 8a to connect the ends of each link plate 8a in the longitudinal direction (left-right direction in the figure).

[0009] The roller link 6 is arranged between a pair of link plates 8a of the pin link 8, and the intermediate portion of one pin 9 of the pin link 8 is inserted into the central hole of one bushing 6b of the roller link 6, thereby connecting the roller link 6 and the pin link 8 so that they can rotate relatively to each other with the pin 9 as the axis of rotation. By repeating this process, a chain 4 as shown in Figure 17 is formed.

[0010] As shown in FIG. 16, a conveying device 2 using such a conventional chain 4 moves a bucket 3 in the traveling direction S of the chain 4 by rotating a driving sprocket wheel (not shown) to drive the chain 4, and during the movement, the bucket 3 scoops up objects to be conveyed (not shown) that have accumulated below the chain 4 (the lower side in the figure) and stores them inside the bucket 3 through an opening 3a of the bucket 3. The bucket 3 is then conveyed along the traveling path of the chain 4, thereby conveying the objects to be conveyed.

[0011] However, with continued use of this type of conveying device 2, when the bucket 3 scoops up an object being transported below the chain 4, the object may come into contact with the chain 4. As a result, the front end (the end on the left side in the figure) and lower end of the link plates located on the outermost sides of the chain 4, particularly the upper link plate 8a of the pin link 8 of the upper chain 4 in Figure 15 and the lower link plate 8a of the pin link 8 of the lower chain 4 in the figure, gradually wear down, resulting in a shortened lifespan of the chain.

[0012] In response to this, the applicant of the present application has proposed a chain in which protective block members are provided on the link plates of the pin links of the chain to protect the ends of the link plates, in order to prevent wear on the link plates of the pin links of the chain and thereby shorten the life of the chain (see Patent Document 1).

[0013] That is, in such conventional chains 14, as shown in Figure 18, a protective block member 20 is fixed with a bolt 21 to the outer surface (the plate surface on the front side in the figure) of one end of the link plate 18a of the pin link 18, i.e., the end on the front side (left side in the figure) in the traveling direction S of the chain 14, and the outer periphery of the protective block 20 on the left side in the figure extends forward and downward from the end of the link plate 18a so as to cover the thickness direction of the link plate 18a, thereby preventing the end of the link plate 18a from coming into contact with the object to be transported. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] Patent Publication No. 2009-040529 Summary of the Invention [Problem to be solved by the invention]

[0015] However, in the conventional chain 14 as described above, there are problems in that the processing costs of the link plates of the pin links increase and the strength of the link plates decreases.

[0016] That is, in conventional conveyor chains 14, in order to attach the protective block member 20 to the link plate 18a of the pin link 18, it was necessary to provide a female screw hole in the link plate 18a. This increased the number of processing steps for the link plate 18a, which could lead to increased processing costs.

[0017] Furthermore, the formation of a female screw hole in link plate 18a reduces the strength of link plate 18a, so in order to ensure the strength of the link plate, it would be necessary to design and manufacture a new link plate with a larger thickness and width, which could lead to more complicated management of chain parts and increased chain costs.

[0018] In view of the above problems, the present invention has an object to provide a chain that can easily and inexpensively prevent a reduction in the chain's lifespan due to wear of the link plates, without having to change the structure of the link plates. [Means for solving the problem]

[0019] In order to solve the above problems, the chain of the present invention is In a chain formed by connecting multiple links, The link includes a pair of link plates and a bushing or a pin connecting respective ends of the pair of link plates in a longitudinal direction, a protection block member having a link protection portion for protecting the link plate is provided at one end of the link plate, The protective block member is attached to the link plate by the pin. 、 The pin has a drop-out prevention portion that engages the protection block member. It is characterized by the above.

[0021] In addition, the chain of the present invention is The link protection portion is provided so as to cover the link plate in the thickness direction. It is characterized by the above.

[0022] In addition, the chain of the present invention is The protection block member is Head The present invention is characterized in that it is provided with a pin protection portion that protects the pin portion.

[0023] In addition, the chain of the present invention is A plurality of roller links, each having a pair of link plates whose end portions in the longitudinal direction are connected to each other by the bushing, and a plurality of pin links, each having a pair of link plates whose end portions in the longitudinal direction are connected to each other by the pin, are alternately connected to each other to form the roller links. It is characterized by the above.

[0024] In addition, the chain of the present invention is One end of the pair of link plates in the longitudinal direction is connected by the bushing, and the other end is connected by the pin, and a plurality of offset links are connected, each of which has an outer width on the bushing side smaller than an inner width on the pin side. It is characterized by the above. Effect of the Invention

[0025] According to such a Chen of the present invention, In a chain formed by connecting multiple links, The link includes a pair of link plates and a bushing or a pin connecting respective ends of the pair of link plates in a longitudinal direction, a protection block member having a link protection portion for protecting the link plate is provided at one end of the link plate, The protection block member is attached to the link plate by the pin, It is possible to easily and inexpensively prevent a reduction in the life of the chain due to wear of the link plates without changing the structure of the link plates. [Brief description of the drawings]

[0026] [Figure 1] 1A and 1B are diagrams showing a chain 24 according to a first embodiment of the present invention, with FIG. 1A being a plan view thereof and FIG. 1B being a side view thereof. [Diagram 2] 2 is an enlarged plan view showing the periphery of a pin link 28 in the chain 24 shown in FIG. 1. [Diagram 3] 2 is an enlarged side view showing the periphery of a pin link 28 in the chain 24 shown in FIG. 1. [Figure 4] 3 is an enlarged cross-sectional view taken along line AA in FIG. 3, showing an enlarged view of a connection portion between a roller link 26 and a pin link 28 in the chain 24 shown in FIG. [Diagram 5] 5A and 5B are diagrams showing a protection block 32, in which FIG. 5A is a front view thereof and FIG. 5B is a right side view thereof. [Figure 6] 6A and 6B are diagrams showing the protective block 32 shown in FIG. 5, with FIG. 6A being a cross-sectional view taken along line BB in FIG. 5A, and FIG. 6B being a cross-sectional view taken along line CC in FIG. 5B. [Figure 7] 2 is a schematic plan view showing a part of a conveying device 22 using a chain 24. FIG. [Figure 8] 8 is a schematic side view of the transport device 22 shown in FIG. 7. [Figure 9]9A and 9B are diagrams showing a chain 44 according to a second embodiment of the present invention, with FIG. 9A being a plan view thereof and FIG. 9B being a side view thereof. [Figure 10] 10 is an enlarged plan view showing the periphery of a pin link 48 in the chain 44 shown in FIG. 9. FIG. [Figure 11] 10 is an enlarged side view showing the periphery of a pin link 48 in the chain 44 shown in FIG. 9. FIG. [Figure 12] 11 is an enlarged cross-sectional view taken along line DD in FIG. 11, showing an enlarged view of a connection portion between a roller link 46 and a pin link 48 in the chain 44 shown in FIG. [Figure 13] 13A and 13B are views showing a protection block 52, in which FIG. 13A is a front view thereof and FIG. 13B is a right side view thereof. [Figure 14] 14A and 14B are diagrams showing the protective block 52 shown in FIG. 13, with FIG. 14A being a cross-sectional view taken along line EE in FIG. 13A, and FIG. 14B being a cross-sectional view taken along line FF in FIG. 13B. [Figure 15] FIG. 1 is a schematic plan view showing a part of a conveying device 2 using a conventional chain 4. [Figure 16] 16 is a schematic side view of the transport device 2 shown in FIG. [Figure 17] 17A and 17B are diagrams showing a conventional chain 4, with FIG. 17A being a plan view thereof and FIG. 17B being a side view thereof. [Figure 18] 1 is an enlarged side view showing the periphery of a pin link 18 of a conventional chain 14. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a chain according to the present invention will be described in detail with reference to the drawings.

[0028] 1 to 8 are diagrams to be referred to in order to explain a chain 24 according to a first embodiment of the present invention and a conveying device 22 using the chain 24. Note that parts similar to those of the conventional chain 4 and conveying device 2 using the chain 4 shown in Figs. 15 to 18 will be described with the same reference numerals, with some exceptions.

[0029] As shown in FIG. 1, a chain 24 according to this embodiment includes a plurality of links (roller links 26 and pin links 28), and is formed by connecting these roller links 26 and pin links 28 alternately.

[0030] As shown in Figure 1(a), the roller link 26, like the roller link 6 of the conventional chain 4 shown in Figure 17, is equipped with a pair of link plates 26a, each formed as a long, thin plate and arranged approximately parallel to each other at a predetermined distance so that their plate surfaces face each other, two cylindrical bushings 26b provided between the pair of link plates 26a to connect each end of each link plate 26a in the longitudinal direction (left and right direction in the figure), and two cylindrical rollers 27 provided on the two bushings 26b so as to be able to rotate around the axis of each bushing 26b as the rotation axis.

[0031] As shown in FIG. 4, each end of the bushing 26b of the roller link 26 in its longitudinal direction (left-right direction in the figure) is integrally fixed to each of the pair of link plates 26a, and each end of the center hole 26c of the bushing 26b in the axial direction (left-right direction in the figure) opens to the outer surface of each link plate 26a, i.e., the plate surface opposite the plate surfaces where the pair of link plates 26a face each other.

[0032] As shown in Figures 2 and 3, the pin link 28 is provided with a pair of link plates 28a, each formed as an elongated plate and arranged approximately parallel to each other at a predetermined distance so that their plate surfaces face each other, and a round bar-shaped pin 29 provided between the pair of link plates 28a to connect one end (left side in Figure 2) of each link plate 28a in the longitudinal direction (left-right direction in Figure 2) and a round bar-shaped pin 9 provided to connect the other end (right side in Figure) of each link plate 28a in the longitudinal direction.

[0033] As shown in FIG. 4, a pair of link plates 28a of the pin link 28 have approximately circular (see FIG. 3) pin holes 28b formed near each end of the length of each link plate 28a, penetrating the link plate 28a in the thickness direction (left-right direction in the figure).

[0034] Like the pin 9 of the pin link 8 of the conventional chain 4 shown in Figure 17, the pin 9 of the pin link 28 has a diameter at the middle of its length that is approximately the same as the inner diameter of the pin hole 28b in the link plate 28a, and at one end (lower in Figure 2) in the length direction (up and down direction), a head 9a is formed that is approximately circular and has a diameter larger than the inner diameter of the pin hole 28b in the link plate 28a, and at the other end (upper in Figure) in the length direction, a through hole 9b is formed that penetrates near the tip of the pin 9 in a direction perpendicular to the axis of the pin 9 (left and right in Figure).

[0035] In contrast, the pin 29 of the pin link 28 has a diameter at the middle of its length that is approximately the same as the inner diameter of the pin hole 28b of the link plate 28a, and at one end (left side in FIG. 4) in the length direction (left-right direction in FIG. 4), a head 29a is formed in an approximately circular plate shape with a diameter larger than the inner diameter of the pin hole 28b of the link plate 28a. At one end (left side in FIG. 4) in the height direction (left-right direction in FIG. 4), a drop-out prevention portion 29c is formed in an approximately circular plate shape with a diameter larger than the outer diameter of the head 29a, and is formed so as to protrude radially outward from the end (left side in FIG. 4) of the outer circumferential surface of the head 29a. At the other end (right side in FIG. 4) of the pin 29 in the length direction, a through hole 29b is formed that penetrates near the tip of the pin 29 in a direction perpendicular to the axis of the pin 29 (up-down direction in FIG. 4).

[0036] The heads 9a, 29a of these two pins 9, 29 engage with the outer surface (the lower plate surface in the figure) of one (lower in Figure 2) of a pair of opposing link plates 28a, and the intermediate portions of the pins 9, 29 are continuously inserted into the pin holes 28b of each link plate 28a, so that the ends of the pins 9, 29 opposite the heads 9a, 29a protrude from the outer surface (the upper plate surface in the figure) of the other (upper in the figure) link plate 28a. A pull-out prevention pin 30 is inserted into through holes 9b, 29b formed at the tips of the protruding pins 9, 29, and the pull-out prevention pin 30 engages with the outer surface of the other link plate 28a, preventing the pins from coming out of the link plate 28a.

[0037] As shown in Figure 4, the roller link 26 is arranged between a pair of link plates 28a of the pin link 28, and the middle portion of one of the two pins 9, 29 of the pin link 28 is inserted into the central hole 26c of one bushing 26b of the roller link 26, thereby connecting the roller link 26 and the pin link 28 so that they can rotate relatively to each other with the pin as the rotation axis. By repeating this process, a chain 24 of any length can be formed.

[0038] In addition, at this time, a ring-shaped oil seal 31 is provided between the link plate 26a of the roller link 26 and the link plate 28a of the pin link 28 to prevent leakage of the lubricating oil filled between the pins 9, 29 and the bushing 26b and to prevent gravel and the like from entering between the pins 9, 29 and the bushing 26b.

[0039] As shown in Figure 2, a protective block member 32 is provided on the outer surface (the plate surface on the lower side in the figure) of one end of one (lower side in the figure) of a pair of opposing link plates 28a of the pin link 28 of the chain 24, i.e., on the end on the front side (left side in the figure) in the traveling direction S of the chain 24.

[0040] As shown in FIG. 5, the protective block member 32 includes a generally plate-shaped main body portion 32a, a link protection portion 32c provided on the rear surface of the main body portion 32a (the surface on the right side in FIG. 5(b)), and a pin protection portion 32d provided on the front surface of the main body portion 32a (the surface on the left side in the figure).

[0041] As shown in Figures 5(a) and 6(a), a substantially circular (see Figure 5(a)) mounting hole 32b is formed in the main body portion 32a of the protective block member 32, penetrating the main body portion 32a in the thickness direction (left-right direction in Figure 6(a)).

[0042] As shown in FIG. 6(b), the link protection portion 32c of the protective block member 32 is formed so that the portion of the outer periphery of the main body portion 32a that continues from the right side of the mounting hole 32b in the figure to the lower side of the mounting hole 32b in the figure protrudes from the back surface of the main body portion 32a in a direction approximately perpendicular to the main body portion 32a (to the left side in the figure) as shown in FIG. 6(a).

[0043] As shown in Figure 5(a), the pin protection portion 32d of the protective block member 32 is formed as a protrusion that protrudes from the front surface of the main body portion 32a toward the right side in the figure, and that is an approximately arc-shaped area that continues from the left side of the mounting hole 32b to the lower side in the figure, at a position located a predetermined distance radially outward from the outer periphery of the mounting hole 32b of the main body portion 32a, as shown in Figure 6(a).

[0044] As shown in Figure 4, such a protective block member 32 is provided on the outer surface of one of the link plates 28a of the pin link 28 of the chain 24 so that the head 29a of the pin 29 protruding from the outer surface (the plate surface on the left side in the figure) of one of a pair of opposing link plates 28a is inserted into the mounting hole 32b of the main body portion 32a, and the back surface (the surface on the right side in the figure) of the main body portion 32a contacts along the outer surface of the link plate 28a.

[0045] At this time, the mounting hole 32b of the main body 32a of the protective block member 32 is formed so that its inner diameter is approximately the same as or slightly smaller than the diameter of the head 29a of the pin 29, so that the head 29a of the pin 29 fits tightly into the mounting hole 32b of the main body 32a of the protective block member 32.

[0046] As shown in FIG. 4, the main body 32a of the protective block member 32 is formed so that its thickness dimension (left-right dimension in the figure) is approximately the same as or slightly smaller than the height dimension (left-right dimension in the figure) from the right-side end of the head 29a of the pin 29 to the anti-fall-off portion 29c. As a result, the anti-fall-off portion 29c of the head 29a of the pin 29 is positioned on the front surface (the left side surface in the figure) of the main body 32a of the protective block member 32 to engage the protective block 32 and prevent the protective block member 32 from coming off the pin 29.

[0047] As shown in FIG. 3, the link protection portion 32c of the protective block member 32 is provided so as to be positioned outside a portion of the outer periphery of the end of the link plate 28a to which the protective block member 32 is provided, which portion continues from the front side (the left side in the figure) to the lower side in the traveling direction S of the chain 24.

[0048] As shown in Figure 4, the link protection portion 32c of the protective block member 32 is formed to protrude from there toward the inside of the pin link 28 (to the right in the figure) so as to cover the thickness direction of the link plate 28a, and its height dimension (left-right dimension in the figure) protruding from the back surface of the main body portion 32a is formed to be larger than the thickness dimension (left-right dimension in the figure) of the link plate 28a of the pin link 28, so that the link protection portion 32c of the protective block member 32 protrudes downward from the front of the end of the link plate 28a of the pin link 28 in the traveling direction S of the chain 24 and covers the end of the link plate 28a.

[0049] As shown in FIG. 4, the thickness dimension (left-right dimension in the figure) of the main body 32a of the protective block member 32 is formed to be smaller than the height dimension (left-right dimension in the figure) of the head 29a of the pin 29. Therefore, when the protective block member 32 is attached to the pin link 28, the head 29a of the pin 29 inserted into the mounting hole 32b of the main body 32a of the protective block member 32 protrudes from the front surface (the left side surface in the figure) of the main body 32a of the protective block member 32 by the amount of the anti-fall-out portion 29c.

[0050] As shown in FIG. 4, the pin protection portion 32d of the protective block member 32 is formed so that its height dimension (the dimension in the left-right direction in the figure) protruding from the front surface of the main body portion 32a is larger than the height dimension (the dimension in the left-right direction in the figure) of the anti-fall-out portion 29c of the head 29a of the pin 29 inserted into the mounting hole 32b of the main body portion 32a of the protective block member 32.

[0051] As a result, as shown in Figure 3, the pin protection portion 32d of the protective block member 32 is located at a position a predetermined distance radially outward from the outer periphery of the anti-fall-out portion 29c of the head 29a of the pin 29 that protrudes from the front surface of the main body portion 32a of the protective block member 32, and is arranged to protrude downward from the front of the anti-fall-out portion 29c of the head 29a of the pin 29 in the traveling direction S of the chain 24.As a result, when the pin link 28 to which the protective block member 32 is attached is viewed from the lower left in the figure, the anti-fall-out portion 29c of the head 29a of the pin 29 that protrudes from the front surface of the main body portion 32a is hidden by the pin protection portion 32d of the protective block member 32.

[0052] According to the chain 24 of this embodiment, by using such a chain in a conveying device, it is possible to prevent a decrease in the lifespan of the chain due to wear of the link plates.

[0053] That is, as shown in FIG. 7, a conveying device 22 using a chain 24 according to this embodiment is similar to the conveying device 2 shown in FIGS. 15 and 16 in that an endless chain 24 is wound around a number of sprocket wheels (not shown), and part of its traveling path is arranged between sprocket wheels (not shown) that are arranged apart in the left-right direction in the figure, with two chains arranged approximately parallel to each other at a predetermined interval in the up-down direction in the figure, and a number of buckets 3 are provided between these two chains 24 at predetermined intervals in the traveling direction S of the chain 24, and each end of the buckets 3 in the width direction (up-down direction in the figure) is connected to each chain 24 via an attachment 5.

[0054] As shown in Figure 8, the bucket 3 is formed in a roughly box-like shape with an opening 3a on the front side (left side in the figure) in the traveling direction S of the chains 24, and is arranged between two chains 24 in part of the traveling path of the chains 24 of the conveying device 22 so that the bucket 3 body and its opening 3a are located below (lower side in the figure) of the chains 24 traveling in the traveling direction S.

[0055] As shown in Figure 7, the link plates positioned outermost on each chain 24, that is, the upper link plate 28a in the upper chain 24 in the figure and the lower link plate 28a in the lower chain 24 in the figure, are provided with a protective block member 32 on the outer surface of one end of the link plate 28a, i.e., the end on the front side (left side in Figure 7) in the traveling direction S of the chain 24.

[0056] In this type of conveying device 22, similar to the conveying device 2 shown in Figures 15 and 16, a driving sprocket wheel (not shown) is rotated to drive the chain 24, thereby moving the bucket 3 in the traveling direction S of the chain 24, as shown in Figure 8, and during this movement, the bucket 3 scoops up objects to be conveyed (not shown) that have accumulated below the chain 24 (the lower side in the figure) and stores them inside the bucket 3 through an opening 3a of the bucket 3. The bucket 3 is then conveyed along the traveling path of the chain 24, thereby conveying the objects to be conveyed.

[0057] Furthermore, during use of the conveying device 22, even if an object to be transported below the chain 24 comes into contact with the chain 24 when the bucket 3 is used to scoop it up, the link protection portion 32c of the protective block member 32 is arranged to cover the thickness direction of the link plate 28a from the front to the bottom of one end of the link plate 28a of the pin link 28 of the chain 24, thereby protecting the end of the link plate 28a. This reduces the frequency with which the object to be transported comes into contact with the end of the link plate 28a, and prevents the link plate 28a from wearing down due to contact with the object to be transported.

[0058] In addition, the pin protection portion 32d of the protective block member 32 is arranged to hide the anti-fall-out portion 29c of the head 29a of the pin 29 protruding from the outer surface of the link plate 28a of the pin link 28, thereby protecting the anti-fall-out portion 29c of the head 29a of the pin 29. This reduces the frequency with which the object to be transported comes into contact with the head 29a of the pin 29 of the pin link 28, and prevents the head 29a of the pin 29 from wearing down due to contact with the object to be transported.

[0059] Furthermore, by preventing wear on the link plates 28a of the pin links 28 and the heads 29a of the pins 29, the life of the chain 24 is prevented from being shortened, and if the protective block member 32 itself becomes worn due to contact with the object of transport, only the worn protective block member 32 can be removed from the pin links 28 and easily replaced with a new protective block member 32.

[0060] Furthermore, in the pin link 28 of the chain 24 of this embodiment, link plates of the same shape and structure can be used for the link plate 28a to which the protective block member 32 is attached and the other link plates 28a, which prevents chain parts management from becoming complicated and prevents increases in chain manufacturing costs.

[0061] In this way, by using the chain 24 of this embodiment, it is possible to easily and inexpensively prevent a reduction in the life of the chain due to wear of the link plates, without changing the structure of the link plates.

[0062] Figures 9 to 14 are diagrams to be referred to in order to explain a chain 44 according to a second embodiment of the present invention. In principle, the same reference numerals are given to the same parts as those of the chain 24 according to the first embodiment shown in Figures 1 to 6, and duplicated explanations will be omitted in principle.

[0063] As shown in Figure 9, a chain 44 according to this embodiment has a different configuration from the chain 24 according to the first embodiment in that, instead of the pin link 28 in the chain 24 according to the first embodiment, it has a pin link 48 as shown in Figures 10 and 11.

[0064] As shown in Figures 10 and 11, the pin link 48 of the chain 44 in this embodiment differs in configuration from the pin link 28 of the chain 24 in the first embodiment in that a protective block member 52 as shown in Figures 13 and 14 is provided instead of the protective block member 32 provided on the pin link 28 of the chain 24 in the first embodiment.

[0065] As shown in Figure 13, the protective block member 52 provided on the pin link 48 of the chain 44 in this embodiment has a substantially plate-shaped main body portion 52a, a link protective portion 52c provided on the back surface of the main body portion 52a (the right surface in Figure 13(b)), and a pin protective portion 52d provided on the front surface of the main body portion 52a (the left surface in the figure).

[0066] Like the main body portion 32a of the protective block member 32 of the chain 24 in the first embodiment, the main body portion 52a of the protective block member 52 is formed with a substantially circular (see Figure 13(a)) mounting hole 52b that penetrates the main body portion 52a in the thickness direction (left-right direction in Figure 14(a)), as shown in Figures 13(a) and 14(a).

[0067] Like the link protection portion 32c of the protective block member 32 of the chain 24 in the first embodiment, the link protection portion 52c of the protective block member 52 is formed so that, as shown in Figure 14(b), the portion of the outer periphery of the main body portion 52a, which continues from the right side of the mounting hole 52b in the figure to the lower side of the mounting hole 52b in the figure, protrudes from the back surface of the main body portion 52a in a direction approximately perpendicular to the main body portion 52a (to the left side in the figure), as shown in Figure 14(a).

[0068] As shown in FIG. 13(a), the pin protection portion 52d of the protective block member 52 is formed as a recess in the outer edge portion of the mounting hole 52b, which is recessed from the front surface of the main body portion 52a toward the rear surface side (left side in the figure) of the main body portion 52a, as shown in FIG. 14(a), leaving behind the outer periphery of the mounting hole 52b on the front surface of the main body portion 52a that continues from the right side of the mounting hole 52b to the lower side in the figure.

[0069] As shown in Figure 10, such a protective block portion 52 is provided on one end of one (lower in the figure) link plate 28a of a pair of opposing link plates 28a of each pin link 48 that constitutes the chain 44, i.e., on the outer surface (lower plate surface in the figure) of the end on the front side (left side in the figure) in the traveling direction S of the chain 44.

[0070] At this time, as shown in FIG. 12, the protective block member 52 is formed so that the thickness dimension (left-right dimension in the figure) of the pin protection portion 52d of the main body portion 52a is approximately the same as or slightly smaller than the height dimension (left-right dimension in the figure) from the right end of the head 29a of the pin 29 to the anti-fall-out portion 29c, and the thickness dimension (left-right dimension in the figure) of the main body portion 52a other than the pin protection portion 52d is larger than the height dimension (left-right dimension in the figure) of the head 29a of the pin 29.

[0071] As a result, the anti-fall-out portion 29c of the head 29a of the pin 29 is positioned on the front surface (the left side surface in the figure) of the pin protection portion 52d of the main body portion 52a of the protective block member 52, engaging the protective block 52 and preventing the protective block member 52 from coming off the pin 29.

[0072] As shown in Figure 12, the anti-fall-out portion 29c of the head 29a of the pin 29 is positioned inside the recess of the pin protection portion 52d of the protective block member 52, and the portion of the front surface of the protective block member 52 other than the pin protection portion 52d, i.e., the outer periphery of the main body portion 52a which continues from the right side of the mounting hole 52b to the lower side in the figure, on the front surface of the main body portion 52a, protrudes downward from the front of the head 29a of the pin 29 in the direction of travel S of the chain 44. As a result, when the pin link 48 to which the protective block member 52 is attached is viewed from the lower left of Figure 11, the anti-fall-out portion 29c of the head 29a of the pin 29 is hidden by the main body portion 52a of the protective block member 52.

[0073] The rest of the configuration is the same as that of the chain 24 of the first embodiment described above, so with this type of chain 44, it is possible to easily and inexpensively prevent a reduction in the chain life due to wear of the link plates without changing the structure of the link plates.

[0074] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention in which the object of the invention can be achieved.

[0075] For example, in the chains 24, 44 according to the first and second embodiments, as shown in Figures 3 and 11, the link protection portions 32c, 52c of the protective block members 32, 52 are formed so as to cover the front and downward portions of the ends of the link plates 28a of the pin links 28, 48, but the link protection portions 32c, 52c may be formed beyond that range to cover other portions, for example, up to the upper part of the ends of the link plates 28a.

[0076] In addition, in the chain 24 of the first embodiment, as shown in FIG. 3, the pin protecting portion 32d of the protective block member 32 is formed in a substantially arc-shaped region that continues from the left side of the head 29a of the pin 29 to the lower side in the figure, but the pin protecting portion 32d may be formed beyond that range and in other parts, for example, in a substantially arc-shaped region that continues to the upper side of the head 29a of the pin 29 in the figure, or in a substantially annular region that surrounds the periphery of the head 29a of the pin 29.

[0077] Furthermore, in the chains 24, 44 according to the first and second embodiments, as shown in Figures 4 and 14, the protective block members 32, 52 are attached to the pin links 28, 48 by fitting the head 29a of the pin 29 into the mounting holes 32b, 52b of the main body portions 32a, 52a and engaging the anti-fall-off portion 29c of the head 29a with the protective block members 32, 52. However, in order to attach the protective block members 32, 52 to the pin links 28, 48, a conventional pin that does not have the anti-fall-off portion 29c, such as the pin 9, may also be used.

[0078] In this case, for example, the inner diameter of the mounting hole 32b, 52b of the protective block member 32, 52 may be formed to be approximately the same as the outer diameter of the intermediate portion of the pin 9 in its length, so that the head 9a of the pin 9 is engaged with the front surface of the main body portion 32a, 52a of the protective block member 32, 52, thereby enabling the protective block member 32, 52 to be attached to the pin link 28, 48.

[0079] In this case, the height dimension of the pin protection portion 32d protruding from the front surface of the main body portion 32a of the protective block member 32 and the depth dimension of the pin protection portion 52d recessed from the front surface of the main body portion 52a of the protective block member 52 may be formed to be greater than the height dimension of the head 9a of the pin 9, so that the head 9a of the pin 9 is protected.

[0080] Alternatively, the protection block members 32,52 may be attached to the pin links 28,48 simply by fitting the heads 9a of the pins 9 into the mounting holes 32b,52b of the main bodies 32a,52a of the protection block members 32,52.

[0081] Furthermore, in the chains 24, 44 according to the first and second embodiments, as shown in Figures 1 and 9, the protective block members 32, 52 are attached to the pin links 28, 48 of the chain 24, 44 formed by alternately connecting roller links 26 and pin links 28, 48. However, the protective block members 32, 52 may also be attached to the pin side end of a link of a chain formed by connecting offset type links, such as a link having a bushing at one end in the longitudinal direction and a pin at the other end, with the outer width of the link on the bushing side being smaller than the inner width on the pin side. [Explanation of symbols]

[0082] 2. Conveyor 3. Bucket 3a opening 4. Chen 5 Attachment 6 Roller Link 6a Link plate 6b Bush 7. Lola 8 pin link 8a Link plate 9-pin 9a head 9b Through hole 14 Chen 18 pin link 18a Link plate 20 Protective block member 21 Fixing bolt 22 Transport equipment 24 Chen 26 Roller Link 26a Link plate 26b Bush 26c center hole 27 Lola 28 pin link 28a Link plate 28b Pinhole 29 pin 29a head 29b Through hole 29c Falling prevention part 30 Locking pin 31 Oil seal 32 Protective block member 32a Main body 32b Mounting hole 32c Link protection section 32d Pin protection 44 Chen 48 pin link 52 Protective block member 52a Main body 52b Mounting hole 52c Link protection section 52d Pin protection part S Direction of travel

Claims

1. In a chain formed by connecting multiple links, The link includes a pair of link plates and a bushing or a pin connecting respective ends of the pair of link plates in a longitudinal direction, a protection block member having a link protection portion for protecting the link plate is provided at one end of the link plate, The protective block member is attached to the link plate by the pin, The pin has a drop-out prevention portion that engages the protection block member. Characterized by Chen.

2. The link protection portion is provided so as to cover the link plate in the thickness direction. A chain as claimed in claim 1.

3. The protective block member is provided with a pin protective portion for protecting the head of the pin. A chain as claimed in claim 1 or 2.

4. A plurality of roller links, each having a pair of link plates whose end portions in the longitudinal direction are connected to each other by the bushing, and a plurality of pin links, each having a pair of link plates whose end portions in the longitudinal direction are connected to each other by the pin, are alternately connected to each other to form the roller links. A chain according to any one of claims 1 to 3.

5. One end of the pair of link plates in the longitudinal direction is connected by the bushing, and the other end is connected by the pin, and a plurality of offset links are connected, each of which has an outer width on the bushing side smaller than an inner width on the pin side. A chain according to any one of claims 1 to 3.

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