EDITORAL NOTE 2012244348 Please note there is no page 1, pages start on 2.
-2 CONVEYOR CHAIN FIELD OF THE INVENTION [0001] The present invention relates to a conveyor chain having carriers for carrying products. The carriers are buckets for holding particulate matter. For example, the conveyor chain is provided in a bucket conveyor. BACKGROUND OF THE INVENTION [0002] A bucket conveyor having a plurality of buckets attached to a conveyor chain is well known (see Patent Document 1 for example). There is also known a conveyor chain composed of a roller chain that includes outer links each composed of a pair of outer link plates and inner links each composed of a pair of inner link plates, connecting pins connecting the outer links with the inner links, and rollers rotatably fitted around bushings that are fitted around the connecting pins, wherein the rollers are flanged rollers having flanges (see Patent Document 2 for example). [PRIOR ART DOCUMENT] [PATENT DOCUMENT] [0003] [Patent Document 1] Japanese Patent Application Laid-open No. 2005-138980 (Paragraphs 0020 to 0022, FIGs. 2 and 3) [Patent Document 2] Japanese Patent Application Laid-open No. 2004-67320 (Paragraphs 0003 to 0006, FIGs. 4 to 6) 7599219_1 (GHMatters) P91741.AU DENISET -3 [0004] When the buckets are attached to the link plates of the conveyor chain having the rollers rotatably fitted around the bushings that are fitted around the connecting pins that connect the outer links with the inner link, the conveyor chain is biased to a side on which the buckets are attached (referred as a "bucket side" hereinafter) in a direction parallel to a center axial line of the bushings (referred to as an "axial direction" hereinafter) and causes misalignment with respect to sprockets or a traveling rail at part of the conveyor chain in which the rollers are not in contact with the sprockets or the traveling rail (referred to a "free span part" hereinafter) due to weight of the buckets or weight of the buckets and of the product stored in the buckets. Then, as shown in FIG. 6, when a roller 530 of a conveyor chain 500 starts to engage with a sprocket 504 or starts to travel on a traveling rail 505 in the condition in which the free-span part of the conveyor chain is misaligned toward the bucket side in terms of the axial direction, a thrust force F that directs to the bucket side in terms of the axial direction may act on the roller 530 and the roller 530 may incline with respect to a center axial line L of the bushing 502 as the roller 530 abuts the sprocket 504 or the traveling rail 505. [0005] If such inclination occurs, there is a case when the roller 530 contacts the inner link plate 521. In such a case, the roller 530 and the inner link plate 521 cause wear due to a force of contact acting on parts of the roller 530 and the inner link plate 521 that contact with each other. This wear is uneven wear that concentrates at the contact part, i.e., a local part, in the inner link plate 521, differing from the roller 530 that rotates. The uneven wear of the inner link plate 521 turns out to be a factor that affects durability of the conveyor chain 500. The closer the position of the contact part to the center axial line L of the bushing 502 and the greater an inclination angle 05 of the roller 530 with respect to the center axial line L, the greater the contact force is. Therefore, speed of advance of the wear of the inner link plate 521 increases in such a case. Accordingly, the durability of the conveyor chain having the flanged roller drops and its maintenance performance drops due to an increase of frequency of maintenance works and maintenance costs (see Japanese Patent Application Laid-open No. 2009-6854). 7599219_1 (GHMatters) P91741.AU DENISET -4 SUMMARY OF THE INVENTION [0006] Accordingly, there is a need to provide a conveyor chain whose durability and maintenance performance are improved upon those described above. [0007] In accordance to a first aspect of the invention, there is provided a conveyor chain, having: outer links composed of first and second outer link plates; inner links composed of first and second inner link plates; connecting pins that articulately connect the outer links with the inner links; bushings fitted around the connecting pins; and rollers rotatably fitted around the bushings; buckets for holding particulate matter attached to the first outer link plates or the first inner link plates on the same side with the first inner link plate in an axial direction in parallel with a center axial line of the bushings; wherein each roller having a roller body having a roller outer circumferential surface contactable with sprockets or a traveling rail, and a flange having an outer diameter which is larger than a diameter of the roller outer circumferential surface at a first roller end of the roller in the axial direction; a washer that prevents the first inner link plate from contacting the roller is disposed between the first inner link plate and the roller in the axial direction and is secured to the first inner link plate; a plate outer peripheral edge of the first inner link plate and a washer outer peripheral edge of the washer are located outside of the roller outer circumferential surface in the radial direction centering on the center axial line; and the washer outer peripheral edge is formed into a shape that keeps away the roller from contacting the first inner link plate by causing the flange contact the first washer at the position radially outside of the roller outer circumferential surface when the roller inclines wherein the roller is an one-side flanged roller having only one flange and is formed into such shape that a plate width of the second inner link plate is smaller than a diameter of 7599219_1 (GHMatters) P91741.AU DENISET -5 the roller outer circumferential surface and a plate outer peripheral edge portion of a plate outer peripheral edge of the second inner link plate is located at the position radially inside of the roller outer circumferential surface in a chain traveling direction; and a second washer that prevents the second inner link plate from contacting the roller is disposed between the second inner link plate and the roller in the axial direction and is secured to the second inner link plate. [0008] In an embodiment, the washer outer peripheral edge is formed into such a shape by which the flange is located at a position contacting the washer outer peripheral edge within an inner side surface of the first inner link plate or at least part thereof is located at the same position with an overlapping outer peripheral edge of an overlap portion, wherein the part where the first inner link plate overlaps with the flange when seen from the axial direction, when the roller inclines. [0009] According to a first aspect of the invention, the roller is an one-side flanged roller having only one flange and is formed into such shape that a plate width of the second inner link plate is smaller than a diameter of the roller outer circumferential surface and a plate outer peripheral edge portion of a plate outer peripheral edge of the second inner link plate is located at the position radially inside of the roller outer circumferential surface in a chain traveling direction, and a second washer that prevents the second inner link plate from contacting the roller is disposed between the second inner link plate and the roller in the axial direction and is secured to the second inner link plate. [0010] Briefly, the conveyor chain of the first aspect of the invention has a roller chain having the outer links composed of the first and second outer link plates, the inner links composed of first and second inner link plates, the connecting pins that articulately connect the outer links with the inner links, the bushings fitted around the connecting pins, the rollers rotatably fitted around the bushings, and the buckets for holding particulate matter attached to the first outer link plates or the first inner link plates on the same side with the first inner link plate in the axial direction in parallel with the center axial line of the bushings. Each roller has the roller body having the roller outer circumferential surface contactable with the sprockets or the traveling rail, and the flange having the outer diameter which is larger than the diameter of the roller outer circumferential surface at the first roller end of the roller in the axial direction. 7599219_1 (GHMatters) P91741.AU DENISET -6 Accordingly, with this arrangement, not only the flange of the roller may prevent the conveyor chain from deviating from the sprockets or the traveling rail, but may also bring about the following advantageous effects. [0011] That is, according to the first aspect of the conveyor chain of the invention, the washer that prevents the first inner link plate from contacting the roller is disposed between the first inner link plate and the roller in the axial direction and is secured to the first inner link plate, the plate outer peripheral edge of the first inner link plate and the washer outer peripheral edge of the washer are located outside of the roller outer circumferential surface in the radial direction centering on the center axial line, and the washer outer peripheral edge is formed into the shape that keeps away the roller from contacting the first inner link plate by causing the flange contact the first washer at the position radially outside of the roller outer circumferential surface when the roller inclines. Accordingly, with this arrangement, the roller may contact the washer when the roller inclines due to the bucket attached to the first outer link plate or the first inner link plate, so that it may be possible to prevent the roller from contacting the first inner link plate and the uneven wear of the first inner link plate from being otherwise caused by the contact of the roller by the washer. Still further, the roller can contact the washer at the position radially outside of the roller outer circumferential surface by the utilization of the flange of the roller, so that the roller contacts the washer at the position separated further from the center axial line and the inclination angle of the roller is reduced as compared to the case when the roller contacts the inner link plate at the position radially inside of the roller outer circumferential surface. Accordingly, it can be possible to reduce the force of contact applied by the roller to the washer and to suppress the advance of the wear of the washer. Then, a life of the conveyor chain may extend due to the washer and to the suppression of the advance of the wear of the washer, so that it may be possible to improve durability and maintenance performance of the conveyor chain. [0012] Still further, the washer that is preferably composed of the material having excellent wear resistance is secured to and integrated with the first inner link plate as another member from the first inner link plate, so that it may be possible to cut production costs as 7599219_1 (GHMatters) P91741.AU DENISET -7 compared to a case when a part that corresponds to the washer is integrally molded with the first inner link plate. [0013] According to an embodiment of the conveyor chain of the invention, the washer outer peripheral edge is formed into such a shape by which the flange is located at a position contacting the washer outer peripheral edge within an inner side surface of the first inner link plate or at least part thereof is located at the same position with an overlapping outer peripheral edge of an overlap portion, wherein the part where the first inner link plate overlaps with the flange when seen from the axial direction, when the roller inclines. Accordingly, with this arrangement, because the washer can be formed into the size by which the washer outer peripheral edge is located at the position contacting the flange or at least the part of the washer outer peripheral edge is located at the same position with the overlapping outer peripheral edge when the roller inclines, the size of the washer may be suppressed. Thus, it may be possible to cut a cost of the washer and to cut costs of the conveyor chain having the washers. [0014] According to the first aspect of the conveyor chain of the invention, the roller is the one-side flanged roller having only one flange and is formed into such shape that the plate width of the second inner link plate is smaller than the diameter of the roller outer circumferential surface and the plate outer peripheral edge portion of the plate outer peripheral edge of the second inner link plate is located at the position radially inside of the roller outer circumferential surface in the chain traveling direction, and the second washer that prevents the second inner link plate from contacting the roller is disposed between the second inner link plate and the roller in the axial direction and is secured to the second inner link plate. Accordingly, with this arrangement, it may be possible to use an existing link plate for the second inner link plate, differing from the first inner link plate having the specific shape in which the plate outer peripheral edge is located at the position radially outside of the roller outer circumferential surface, so that it may be possible to cut the cost of the conveyor chain having the washers further. 7599219_1 (GHMatters) P91741.AU DENISET -8 Still further, the second washer that prevents the roller from contacting the second inner link plate may be disposed between the second inner link plate and the roller in the axial direction and is secured to the second inner link plate. Accordingly, with this arrangement, the roller may contact the second washer and may not contact the second inner link plate. Therefore, the second washer may prevents uneven wear from occurring on the second inner link plate otherwise caused by the contact with the roller. Still further, the inclination angle of the roller may be reduced as the flange contacts the washer at the position radially outside of the roller outer circumferential surface when the roller inclines, the force of contact applied by the roller to the second inner link plate may be reduced and the advance of the wear of the second washer is suppressed when the roller contacts the second washer. Accordingly, it may be possible to improve durability and maintenance performance of the conveyor chain. BRIEF DESCRIPTION OF DRAWINGS Embodiment of the invention and other embodiments, will now be described by way of example only with reference to the accompanying drawings in which [0015] FIG. 1 shows an embodiment and is a schematic entire diagram of a bucket conveyor having a conveyor chain; [0016] FIG. 2 is a section view of the conveyor chain shown in FIG. 1 taken along a line 11 II; [0017] FIG. 3A is a partially section view of a main part of the conveyor chain taken in the direction of an arrow 111-111 in FIG. 2; [0018] FIG. 3B is an enlarged view of a part of the conveyor chain shown in FIG. 3A; [0019] FIG. 4A is a view of the conveyor chain taken in the direction of an arrow IV-IV in FIG. 3; [0020] FIG. 4B is a section view taken along a line b-b in FIG. 4A; 7599219_1 (GHMatters) P91741.AU DENISET -9 [0021] FIG. 5 corresponds to a section view taken along a line V-V in FIG. 3 and illustrates one example of contact position of a roller and an inner link plate of the conveyor chain; and [0022] FIG. 6 shows a prior art and corresponds to FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] [0023] A first embodiment of a conveyor chain will be explained with reference to FIGs. 1 through 5. As shown in FIG. 1, a bucket conveyor 1 as a conveyor chain type conveyor having a conveyor chain 100 of an embodiment is configured to convey particulate matter 7 (including particulate and powdery matters). [0024] As shown also in FIG. 2, the bucket conveyor 1 includes a frame 2, one or more, i.e., one here, conveyor chain member 3 supported by the frame 2, a predetermined number more than one, i.e., a pair here, of conveyor chains 100 composing the conveyor chain member 3, a chain driving unit 4 that drives the conveyor chain member 3, traveling rails 5 of the predetermined number that are supported by rail supporting portions 21 and 22 of the frame 2 to guide the respective conveyor chains 100, and a plurality of buckets 6 attached to the conveyor chain member 3. [0025] The pair of conveyor chains 100 composing the conveyor chain member 3 is disposed at a predetermined distance from each other in a chain width direction (see FIG. 2). The buckets 6 attached to the conveyor chain member 3 are all attached to the pair of conveyor chains 100 at equal predetermined pitches in tandem in a chain traveling direction. The bucket 6 is a carrier for holding or storing particulate matter as products to be conveyed. It is noted that FIG. 1 shows a part of the buckets 6. 7599219_1 (GHMatters) P91741.AU DENISET - 10 [0026] The chain driving unit 4 includes a sprocket unit 41 having the predetermined number of sprocket members each composed of a driving sprocket 42 and a driven sprocket 43 around which the endless conveyor chain 100 is wrapped around, and an electric motor 44 as a driving source for rotating and driving each driving sprocket 42. The respective sprockets 42 and 43 are rotatably supported by sprocket supporting members not shown of the frame 2. [0027] The traveling rails 5 include a convey-side rail 51 for guiding the conveyor chain 100 that conveys the buckets 6 storing the particulate matter 7 carried into the buckets 6 at a carry-in area Al, and a return rail 52 for guiding the conveyor chain 100 that conveys the empty buckets 6 from which the particulate matter 7 has been carried out in a carry-out area A2. The rails 51 and 52 are supported by the rail supporting portions 21 and 22 of the frame 2, respectively. [0028] Each bucket 6 having an opening 61 for carrying in and out the particulate matter 7 scoops in the particulate matter 7 or scraped out the particulate matter 7 from or to stock 70 in which the particulate matter 7 is stocked. The particulate matter 7 stored in and carried by the bucket 6 is carried out to a carry-out conveyor not shown at a carry-out area A2 which is disposed above the carry-in area Al. That is, the bucket conveyor 1 is a bucket elevator that conveys the particulate matter 7 in the vertical direction. [0029] As shown in FIGs. 3 and 4, each conveyor chain 100 is a roller chain including a plurality of outer links 110, a plurality of inner links 120, a plurality of connecting pins 101 articulately connecting the outer links 110 with the inner links 120 that adjoin with each other in the chain traveling direction, a plurality of bushings 102 each fitted around each connecting pin 101, a plurality of rollers 130 each fitted rotatably around each bushing 102, and first and second washers 140 and 150, i.e., a plurality of sets of washers, disposed on both ends of each roller 130 in an axial direction. 7599219_1 (GHMatters) P91741.AU DENISET - 11 Here, the axial direction is a direction parallel with a center axial line L of the bushing 102 and is the chain width direction. A radial direction is a direction radial centering on the center axial line L. [0030] Each outer link 110 is composed of a first outer link plate 111 and a second outer link plate 112 disposed separately from each other in the axial direction. The first outer link plate 111 located on a bucket side on one direction in the axial direction, i.e., located on the same side with a first inner link plate 121 in the axial direction described later, is a carrier attachment link plate to which the bucket 6 (see FIGs. 1 and 2) is attached in the conveyor chain 100. The first outer link plate 111 has a plurality of attachment portions 111a to which the bucket 6 is attached by bolts not shown as attachment means through an intermediary of an attachment 8 (see FIG. 2). The first outer link plate 111a is provided with an insertion hole 111b through which the attachment bolt is inserted. The second outer link plate 112 is located on a side opposite from the bucket (referred to as the 'anti-bucket side' hereinafter) as another side in the axial direction. A plate width W12 of the second outer link plate 112 is smaller than a plate width WIl of the first outer link plate 111 and a plate width W22 of a second inner link plate 122 described later. [0031] The inner link 120 is composed of a first inner link plate 121 on the bucket side and the second inner link plate 122 on the anti-bucket side disposed separately between the first and second outer link plates 111 and 112 in the axial direction. The plate width W21 of the first inner link plate 121 is larger than a diameter Dr of a roller outer circumferential surface 132 described later and is more preferably lager than an outer diameter Df of a flange 137 described later, However, the plate width W21 is equal to the outer diameter Df in the present embodiment. Then, the first outer link plate 111 and the first inner link plate 121 are disposed so as to face with each other respectively in the axial direction in the pair of conveyor chains 100 (see FIG. 2). [0032] A plate width W22 of the second inner link plate 122 is smaller than the plate width W21 of the first inner link plate 121 and the diameter Dr of the roller outer 7599219_1 (GHMatters) P91741.AU DENISET - 12 circumferential surface 132. Still further, a plate outer peripheral edge portion 124a in the chain traveling direction of a plate outer peripheral edge 124 of the second inner link plate 122 is located inwardly in the radial direction more than a plate outer peripheral edge portion 123a in the chain traveling direction of a plate outer peripheral edge 123 of the first inner link plate 121 and more than a roller outer circumferential surface 132. [0033] As shown also in FIG. 5, each bushing 102 is secured by being press-fitted into holes 127 and 128 provided through the first and second inner link plates 121 and 122 and is disposed between the first and second inner link plates 121 and 122 in the axial direction. [0034] As shown in FIG. 5, a small radial gap Cr is created between an outer circumferential surface 102a of the bushing 102 and an inner circumferential surface 135 of the roller 130 and small axial gaps Ca are created between respective washers 140 and 150 and respective roller end faces 133a and 134a and a flange end face 137a of the roller 130. It is noted that in FIG. 5, the radial gap Cr and the axial gap Ca are exaggerated for convenience of the description. [0035] As shown in FIGs. 3 through 5, the roller 130 that engages with the sprockets 42 and 43 (see FIG. 1) and rolls on the traveling rail 5 in contact with the traveling rail 5 (see FIGs. 1 and 2) has a roller body 131 having a roller outer circumferential surface 132 and a flange 137 as part of a first roller end 133 on the bucket side of the roller body 131 in the axial direction. The roller outer circumferential surface 132 engages with the sprockets 42 and 43 and rolls in contact with the traveling chain 5. [0036] The flange 137 is a part located radially outward of the roller outer circumferential surface 132 and has a flange outer peripheral edge 138 that defines an outer diameter Df which is larger than the diameter Dr of the roller outer circumferential surface 132. The roller body 131 has a second roller end 134 on the anti-bucket side on the opposite side from the first roller end 133 in the axial direction. Accordingly, the roller 130 is a flanged roller or a unilateral flanged roller having the flange 137 only on one side of the roller 130. 7599219_1 (GHMatters) P91741.AU DENISET - 13 [0037] The first washer 140 (dotted in FIG. 4b) prevents the first roller end 133 or the flange 137 on the bucket side (or flange side) from contacting the first inner link plate 121. The second washer 150 prevents the second roller end 134 on the anti-bucket side or on the anti-flange side) from contacting the second inner link plate 122. The disc-like washers 140 and 150 are composed of a highly abrasion-resistant material such as high-tensile steel or hardening steel. [0038] The washer 140 is disposed between the first inner link plate 121 and the first roller end 133 or the flange 137 in the axial direction and is located radially within the inner side surface 121a of the first inner link plate 121, i.e., radially within the plate outer peripheral edge 123, as a whole. The washer 140 is secured integrally with the first inner link plate 121 by means of welding, as securing means, to the inner side surface 121a. The first roller end 133 or the flange 137 is contactable with the washer 140 in the axial direction. [0039] The plate outer peripheral edge 123 of the first inner link plate 121 and the washer outer peripheral edge 141 of the washer 140 are located radially outside of the roller outer circumferential surface 132. The washer outer peripheral edge 141 is formed into a shape that keeps away the roller 130 including the flange 137 from contacting the inner side surface 121a of the first inner link plate 121 by causing the flange 137 contact the washer 140 at a contact point P located radially outside the roller outer circumferential surface 132 when the roller 130 inclines relatively with respect to the center axial line L (see FIG. 5). It is noted that the term "shape" includes size. [0040] As described above, this inclination of the roller 130 is caused by the weight of the bucket 6 or of the bucket 6 and the particulate matter 7 stored in the bucket 6 in the free span portion 100f of the conveyor chain 100 (FIG. 1 shows one example thereof). That is, the roller 130 is biased toward the bucket-side in the axial direction and is misaligned in the axial direction with respect to the sprockets 42 and 43 (see FIG. 1) and the traveling rail 5 (see FIGs. 1 and 2). This inclination occurs as a thrust force F (see FIG. 5) in a direction heading to the flange side in the axial direction acts when the roller 130 starts to engage with the sprocket 42 7599219_1 (GHMatters) P91741.AU DENISET - 14 or 43 or starts to contact the traveling rail 5, i.e., when the roller 130 starts to travel on the traveling rail 5. [0041] Then, an inclination angle 01 caused when the roller 130 inclines is reduced as compared to an inclination angle, e.g., an inclination angle 05 shown in FIG. 6, when the roller 130 contacts the inner link plate at position inward in the radial direction more than the roller outer circumferential surface 132. [0042] As shown in FIGs. 3 and 4B, the washer outer peripheral edge 141 is formed so that at least part of the washer outer peripheral edge 141 is located at the same position with a overlapping outer peripheral edge 161 of a overlap portion 160 (cross-hatched in FIG. 4B). Here, the overlap portion 160 is a part where the first inner link plate 121 overlaps with the flange 137 when seen in the axial direction in a condition in which the center axial line L coincides with a center line, i.e., an center axial line of the pin 101. [0043] More specifically, the washer outer peripheral edge 141 is formed such that the part thereof is located at the same position with the overlapping outer peripheral edge 161 of the overlap portion 160 and the remaining part is located at the same position with the overlapping outer peripheral edge 161 or is located radially outside of the overlapping outer peripheral edge 161. Then, in the present embodiment, a first outer peripheral edge portion 141a which is a part of the washer outer peripheral edge 141 is located at the same position with the overlapping outer peripheral edge 161 and a second outer peripheral edge portion 141b which is the remaining part other than the first outer peripheral edge portion 141a of the washer outer peripheral edges 141 and 151 is located at the position radially outside of the overlapping outer peripheral edge 161 as shown in FIG. 4B. [0044] The second washer 150 is disposed between the second inner link plate 122 and the second roller end 134 in the axial direction and is located radially within the inner side surface 122a of the second inner link plate 122, i.e., within the plate outer peripheral edge 124 as a whole. The second washer 150 is secured integrally with the second inner link plate 122 by welding to the inner side surface 122a. The second roller end 134 is contactable with the second washer 150 in the axial direction. 7599219_1 (GHMatters) P91741.AU DENISET - 15 A washer outer peripheral edge 151 of the second washer 150 is located at a position radially outside of the roller outer circumferential surface 132 and has a diameter equal to or less than the plate width W22 of the second inner link plate 122. The washer outer peripheral edge 151 has a diameter equal to the plate width W22 in the present embodiment. [0045] Next, the operations and effects of the embodiment constructed as described above will be explained. The conveyor chain 100 includes the first and second outer link plates 111 and 112, the first and second inner link plates 121 and 122, the connecting pins 101 that articulately connect the outer link plates with the inner link plates, the bushings 102 fitted around the connecting pins 101 and the rollers 130 rotatably fitted around the bushings 102. Then, the bucket 6 for holding the particulate matter 7 is attached to the first outer link plate 111. The roller 130 has the roller body 131 having the roller outer circumferential surface 132 contactable with the sprockets 42 and 43 or the traveling rail 5 and the flange 137 having the outer diameter Df which is larger than the diameter of the roller outer circumferential surface 132 at the first roller end 133 of the roller 130 in the axial direction. [0046] With this arrangement, the conveyor chain 100 having the first outer link plate 111 to which the bucket 6 for holding the particulate matter 7 is attached is the roller chain having the flanged roller, so that the flange 137 of the roller 130 prevents the conveyor chain 100 from deviating from the sprockets 42 and 43 or the traveling rail 5. [0047] The washer 140 that prevents the first inner link plate 121 from contacting the roller 130 is disposed between the first inner link plate 121 and the roller 130 in the axial direction and is secured to the first inner link plate 121. The plate outer peripheral edge 123 of the first inner link plate 121 and the washer outer peripheral edge 141 of the washer 140 are located outside of the roller outer circumferential surface 132 in the radial direction centering on the center axial line L. The washer outer peripheral edge 141 is formed into the shape that keeps away the roller 130 from contacting the first inner link plate 121 by causing the flange 137 contact the first washer 140 at the position radially outside of the roller outer circumferential surface 132 when the roller inclines. [0048] With this arrangement, the roller 130 contacts the washer 140 when the roller 130 inclines due to the bucket 6 attached to the first outer link plate 111 or the first inner link 7599219_1 (GHMatters) P91741.AU DENISET - 16 plate 121, so that it is possible to prevent the roller 130 from contacting the first inner link plate 121 and the uneven wear of the first inner link plate 121 from being otherwise caused by the contact of the roller 130 by the washer 140. Still further, the roller 130 contacts the washer 140 at the position radially outside of the roller outer circumferential surface 132 by the utilization of the flange 137 of the roller 130, so that the roller 130 contacts the washer 140 at the position separated further from the center axial line L and the inclination angle 01 of the roller 130 is reduced as compared to the case when the roller 130 contacts the inner link plate at the position radially inside of the roller outer circumferential surface 132. Accordingly, it is possible to reduce the force of contact applied by the roller 130 to the washer 140 and to suppress the advance of the wear of the washer 140. Then, a life of the conveyor chain 100 extends due to the washer 140 and to the suppression of the advance of the wear of the washer 140, so that it is possible to improve durability and maintenance performance of the conveyor chain 100. Still further, the washer 140 that is preferably composed of the material having the excellent wear resistance is secured to and integrated with the first inner link plate 121 as the other member from the first inner link plate 121, so that it is possible to cut production costs as compared to a case when a part that corresponds to the washer 140 is integrally molded with the first inner link plate 121. [0049] The washer outer peripheral edge 141 has such shape that the first outer peripheral edge portion 141a which is at least the part of the washer outer peripheral edge 141 is located at the same position with the overlapping outer peripheral edge 161 of the overlap portion 160 and the second outer peripheral edge portion 141b which is the remaining part other than the first outer peripheral edge portion 141a is located at the position radially outside of the overlapping outer peripheral edge 161. [0050] With this arrangement, because the washer 140 is formed into the size in which at least the first outer peripheral edge portion 141a which is the part of the washer outer peripheral edge 141 is located at the same position with the overlapping outer peripheral edge 161, the size of the washer 140 is suppressed. Thus, it is possible to cut a cost of the washer 140 and to cut costs of the conveyor chain 100 having the washers 140. 7599219_1 (GHMatters) P91741.AU DENISET - 17 [0051] The roller 130 is the one-side flanged roller having only one flange 137 and formed into such shape that the plate width W22 of the second inner link plate 122 is smaller than the diameter of the roller outer circumferential surface 132 and the plate outer peripheral edge portion 124a of the plate outer peripheral edge 124 of the second inner link plate 122 is located at the position radially inside of the roller outer circumferential surface 132. [0052] with this arrangement, it is possible to use an existing link plate for the second inner link plate 122, differing from the first inner link plate 121 having the specific shape in which the plate outer peripheral edge 123 is located at the position radially outside of the roller outer circumferential surface 132. Accordingly, it is possible to cut the cost of the conveyor chain 100 having the washers 140 further. [0053] The second washer 150 that prevents the roller 130 from contacting the second inner link plate 122 is disposed between the second inner link plate 122 and the roller 130 in the axial direction and is secured to the second inner link plate 122. [0054] With this arrangement, the roller 130 contacts the second washer 150 and does not contact the second inner link plate 122. Therefore, the second washer 150 prevents uneven wear from occurring on the second inner link plate 122 otherwise caused by the contact with the roller 130. Still further, the inclination angle of the roller 130 is reduced as the flange 137 contacts the first washer 140 at the position radially outside of the roller outer circumferential surface 132 when the roller inclines, the force of contact applied by the roller 130 to the second inner link plate 122 is reduced and the advance of the wear of the second washer 150 is suppressed when the roller 130 contacts the second washer 150. Accordingly, it is possible to improve durability and maintenance performance of the conveyor chain 100. [0055] A modified embodiment in which a part of the configuration of the abovementioned embodiment will be explained concerning the modified configuration. That is, the washer outer peripheral edge 141 of the washer 140 may have such a shape that the flange 137 is located at a position contacting with the washer outer peripheral edge 141 at the flange outer peripheral edge 138 or in a vicinity of the flange outer peripheral edge 138 within the inner side surface 121a of the first inner link plate 121 when the roller inclines. In this case, the washer outer peripheral edge 141 may be located at a radially inside 7599219_1 (GHMatters) P91741.AU DENISET - 18 position of the overlapping outer peripheral edge 161 of the overlap portion 160 as a whole or partially. Then, with this arrangement, the washer 140 is formed into the size by which the washer outer peripheral edge 141 is located at the position contacting with the flange 137 when the roller inclines, so that the size of the washer 140 can be suppressed. Accordingly, it is possible to cut the cost of the washer 140 and to cut the cost of the conveyor chain 100 having the washer 140. [0056] The whole washer outer peripheral edge 141 may be located at the same position with the overlapping outer peripheral edge 161. The washer outer peripheral edge 141 is formed into the size so as to be located at the same position with the overlapping outer peripheral edge 161 also in this case, so that it is possible to suppress the size of the washer 140 and to cut the cost of the washer 140. The carrier attaching link plate may be at least one link plate of the first outer link plate 111 and the first inner link plate 121. [0057] The specific mode of the conveyor chain may take any mode as long as the conveyor chain is the roller chain having the outer links composed of the first and second outer link plates, the inner links composed of first and second inner link plates, the connecting pins that articulately connect the outer links with the inner links, the bushings fitted around the connecting pins, the rollers rotatably fitted around the bushings, and the buckets for holding particulate matter attached to the first outer link plates or the first inner link plates on the same side with the first inner link plate in the axial direction in parallel with the center axial line of the bushings. Then, each roller has the roller body having the roller outer circumferential surface contactable with the sprockets or the traveling rail, and the flange having the outer diameter which is larger than the diameter of the roller outer circumferential surface at the first roller end of the roller in the axial direction. Then, the washer that prevents the first inner link plate from contacting the roller is disposed between the first inner link plate and the roller in the axial direction and is secured to the first inner link plate, the plate outer peripheral edge of the first inner link plate and the 7599219_1 (GHMatters) P91741.AU DENISET - 19 washer outer peripheral edge of the washer are located outside of the roller outer circumferential surface in the radial direction centering on the center axial line, and the washer outer peripheral edge is formed into the shape that keeps away the roller from contacting the first inner link plate by causing the flange contact the first washer at the position radially outside of the roller outer circumferential surface when the roller inclines. Then, it is possible to prevent the roller from contacting the inner link plate, the uneven wear of the inner link plate from being otherwise caused by the contact of the roller by the washer when the roller inclines due to the bucket attached to the link plate, and thus to improve durability and maintenance performance. [0058] The product to be carried may be articles that can be counted, other than the particulate matter, e.g., grains, earth and sand, granulated slag and others. The carrier may be the bucket or not and the conveyor chain may be provided in a chain-type conveyor other than the bucket conveyor. [0059] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. [0060] It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country. 7599219_1 (GHMatters) P91741.AU DENISET - 20 [DESCRIPTION OF REFERENCE NUMERALS] [0061] 100 Conveyor chain 101 Connecting pin 102 Bushing 110 Outer link 111, 112 outer link plate 120 Inner link 121, 122 inner link plate 123, 124 Plate outer peripheral edge 130 Roller 131 Roller body 132 Roller outer circumferential surface 137 Flange 140, 150 Washer 141, 151 Washer outer peripheral edge 160 Overlap portion 161 Overlap outer peripheral edge L center axial line 7599219_1 (GHMatters) P91741.AU DENISET