JP4076281B2 - Seal chain - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seal chain used for power transmission in motorcycles and various industrial machines.
[0002]
[Prior art]
FIG. 2 is a plan view (a partial cross-sectional view) showing an example of a conventional general seal chain. As shown in FIG. 2, the seal chain 50 includes a pair of inner link plates 52a and 52a arranged in parallel, and cylindrical bushes that connect the inner link plates 52a and 52a at the respective end portions on both sides. A plurality of inner links 52 including 51 and 51, a pair of outer link plates 55a and 55a arranged in parallel, and pins 53 that connect between the outer link plates 55a and 55a at the respective end portions on both sides. , 53, and the inner link 52 and the outer link 55 are alternately connected in such a manner that the pins 53 of the outer link 55 are rotatably inserted into the bushes 51 of the inner link 52. Has been. A rubber O-ring is inserted between the inner link 52 and the outer link 55 around the pin 53 (or the bush 51) and sandwiched between the inner link plate 52a and the outer link plate 55a. A seal ring 56 made of (for example, having a cross-sectional diameter of about 2 mm) is attached. The seal ring 56 is in close contact with the inner link plate 52a and the outer link plate 55a in a compressed form of about 10 to 25%, so that the grease between the bush 51 and the pin 53 leaks to the outside. In addition, foreign matter does not enter between the bush 51 and the pin 53 from the outside. In addition, the space | interval L50 of FIG. 2 has shown the space | interval of the inner link plate 52a and the outer link plate 55a.
[0003]
FIG. 3 is a plan view (a partial cross-sectional view) showing an example of a conventional chain having no seal ring. As shown in FIG. 3, in the chain 60 having no seal ring, the distance L60 between the inner link plate 62a of the inner link 62 and the outer link plate 65a of the outer link 65 is the same as that described above because the seal ring is not attached. It is smaller than the distance L50 in the seal chain 50 of FIG.
[0004]
[Problems to be solved by the invention]
As described above, in the seal chain, the distance between the inner link plate and the outer link plate must be structurally larger than the chain without the seal ring by the amount of the arrangement of the seal ring. As a result, the length of the material increases, which causes an increase in weight and size. Moreover, since the length of a pin becomes large, the problem that the rigidity and intensity | strength will fall easily also arises. In order to prevent a decrease in rigidity and strength of the pin, the bush length is made longer than usual, and a seal ring is attached around the bush. However, since the bush length is increased, the weight is only increased. Alternatively, the rigidity and strength of a chain without a seal ring cannot be expected, and the effect is weak.
[0005]
In general seal chains, the seal ring has a relatively large cross-sectional diameter of about 2 mm because of the ability to follow the inner and outer link plates of the seal ring during lateral vibration of the chain. This prevents the seal from being removed and grease leakage is promoted, and as a result, the wear resistance of the chain is not sufficiently exhibited). That is, when the chain vibrates laterally or there is a sprocket offset or the like, the size of the interval (L50) between the inner and outer link plates changes, so the seal sandwiched between these inner and outer link plates. The compression ratio of the ring (56) will change. Therefore, the seal ring needs to be elastic enough to follow the change in the compression rate, and for that purpose, the above-mentioned 2 mm of meat pressure is required.
[0006]
That is, in the seal chain, it is difficult to reduce the space between the inner and outer link plates by reducing the wall pressure of the seal ring. In addition, as a method of improving the followability of the seal chain, there is a method in which the cross-sectional shape of the seal ring is an X shape. In order to enable such a complicated shape, the seal ring has a cross-section of a certain size. This is necessary and the distance between the inner and outer link plates cannot be reduced. Further, as the cross-section of the seal ring is reduced, it is necessary to increase the accuracy and assembly accuracy of each component, which causes a problem that manufacturing becomes difficult and cost increases.
[0007]
Therefore, in view of the above circumstances, the present invention eliminates the need to increase the distance between the inner link plate of the inner link and the outer link plate of the outer link, and therefore can suppress an increase in weight and size, and has an appropriate rigidity. It is another object of the present invention to provide a seal chain having high strength.
[0008]
[Means for Solving the Problems]
This invention is made | formed in view of the said situation, Comprising: The inner link (3) provided with a pair of inner link plates (3a, 3a) which fitted the bush (2) and this bush (2) to the both ends ) And an outer link (6) comprising a pin (5) and a pair of outer link plates (6a, 6a) connected to each other via the pin (5), the pair of inner link plates ( 3a, 3a) are inserted and arranged inside the pair of outer link plates (6a, 6a), and the pin (5) is rotatably inserted and connected to the bush (2). In the seal chain (1) provided by rotatably inserting the roller (9) on the outer periphery of (2), the inner link plate (3a) is disposed outside the inner link plate (3a). A first sealing member (7) between the outer link plate (6a) The first seal member (7) is sandwiched between the inner link plate (3a) and the outer link plate (6a), and the pin (5) is surrounded by the first seal member (7). The bush (2) includes a first bush piece (20) provided on one inner link plate (3a) of the pair of inner link plates (3a) and the other. The second bushing piece (20) provided on the inner link plate (3a) of the inner link plate (3a) has a second bushing piece (20) that can freely approach and retract along the pin (5) inserted into the bushing (2). A seal ring (10, 10) is provided on the outer periphery of the first and second bush pieces (20, 20) between the pair of inner link plates (3a, 3a) and the roller (9). In the seal chain (1) constructed by inserting and fitting each .
[0009]
Preferably, a clearance (CL1) is formed between the first bushing piece (20) and the second bushing piece (20) so that the inside and outside of the bushing (2) communicate with each other.
[0010]
Further, the opening end faces (9a, 9a) on both sides of the roller (9) are tapered so that the inner peripheral side is recessed.
[0011]
Note that the numbers in parentheses are for the sake of convenience indicating the corresponding elements in the drawings, and therefore the present description is not limited to the descriptions on the drawings. The same applies to the following operations.
[0012]
[Action]
Based on the above configuration, in the seal chain (1) according to the present invention, the space between the end (2a) of the bush (2) and the pin (5) is sealed by the first seal member (7), and the roller ( The space between the open end face (9a) of 9) and the bush (2) is sealed by a seal ring (10). When the seal chain (1) undergoes lateral vibration, the inner link plate (3a) and the outer link plate (6a) sandwiching the first seal member (7) tend to move relatively close to each other. However, the pair of inner link plates (3a, 3a) utilizes the approaching / retracting action of the first and second bush pieces (20, 20) connecting these (3a, 3a) and seal ring. The outer link plates (6a, 6a, 6a, 10) are pressed against the roller (9) in the outer direction so that the distance (L1) between the outer link plates (6a, 6a) is kept constant. Move so as to follow 6a).
[0013]
【The invention's effect】
According to the present invention (Claim 1), even when the seal chain is laterally vibrated, the inner link plate is opposed to the outer link plate disposed with the first seal member such as an elastic sheet interposed therebetween. Since the follow-up movement is performed in such a manner that the distance between the inner and outer link plates is kept constant, the seal between the bush and the pin by the first seal member is maintained well. As a result, grease leakage and the like are prevented, wear prevention between the bush and the pin or between the bush and the roller is guaranteed, and an excellent seal chain with high wear resistance is provided. Further, in the conventional seal chain, in order to ensure the sealing effect by the seal member such as the seal ring 56 between the inner link plate and the outer link plate, it can be deformed corresponding to the change in the interval between the inner and outer link plates. However, in the present invention, the sealing effect by the first seal member between the inner link plate and the outer link plate is the followability between the inner and outer link plates. Therefore, it is not necessary to rely on the elastic performance of the first seal member, and accordingly, the first seal member can be made thinner and the distance between the inner and outer link plates can be made narrower than that of the conventional seal chain. Furthermore, in the present invention, in order to ensure the sealing effect by the first seal member, the seal ring is provided with elastic performance and the like so that the inner link plate can be pressed against the outer link plate. Located between the pair of inner link plates. However, the inner link can be configured with a width comparable to the inner link width in the conventional chain by slightly reducing the roller width by the amount of the seal ring. As described above, in the seal chain according to the present invention, it is not necessary to make the width of the chain, and thus the length of the pin, etc. particularly longer than that of a conventional chain (a chain that is not a seal chain). In addition, since it is not necessary to increase the length of the pin, the rigidity and strength of the pin are not lowered correspondingly, so that a seal chain having appropriate rigidity and strength can be obtained. In addition, since it is not necessary to make the cross-section of the seal ring particularly small, it is not necessary to increase the accuracy and assembly accuracy of each part, and the manufacturing is easy and the cost is not increased.
[0014]
When a clearance such as a clearance interval CL1 is formed between the first bushing piece and the second bushing piece so that the inside and outside of the bush communicate with each other (Claim 2), The bushing piece and the second bushing piece approach and retract smoothly, thereby ensuring good followability between the inner and outer link plates, so that the wear resistance of the seal chain becomes higher. In addition, since the weight of the entire chain is reduced by the amount of clearance, it is convenient. The first and second bush pieces are pressed in a direction retreating from each other by a pair of inner link plates connected by them and a seal ring that presses the inner link plates outward against the rollers. As a result, the ends facing each other through the clearance do not collide and make noise.
[0015]
Further, when the opening end faces on both sides of the roller are tapered with the inner peripheral side being recessed (Claim 2), the contact between the roller and the seal ring is performed via the opening end faces that are tapered. Therefore, it is convenient because the seal ring is pressed against the bush and does not come out accidentally.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the seal chain according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view (a partial cross-sectional view) showing an example of a seal chain according to the present invention.
[0017]
As shown in FIG. 1, the seal chain 1 has a plurality of inner links 3 and a plurality of outer links 6. The inner links 3 and the outer links 6 are in a predetermined link connection direction, which is indicated by an arrow A in FIG. They are alternately connected one by one in the B direction. Each inner link 3 has a pair of inner link plates 3a, 3a, which are in a predetermined link axis direction perpendicular to the above-described link connection direction (the directions of arrows A and B in FIG. 1). The inner link plates 3a, 3a have bushes at the respective end portions (the end portions on the arrow A side and the end portion on the arrow B side) of the inner link plates 3a, 3a. 2 is provided so as to be fitted to the inner link plates 3a and 3a.
[0018]
Each bush 2 is composed of two bush pieces 20, 20, and each bush piece 20 is a substantially cylindrical member extending in the link axis direction (the direction of arrows C, D in FIG. 1). The bush pieces 20 and 20 constituting the bush 2 are arranged in series in the link axial direction, and a clearance interval CL1 (gap) in the link axial direction is provided between the bush pieces 20 and 20 (that is, these). The bush pieces 20, 20 are not joined.) Further, both end portions (the end portion on the arrow C side and the end portion on the arrow D side) of each bush 2, that is, the end portion 2 a of each bush piece 20 constituting the bush 2, is an inner link connected by the bush 2. Plates 3a and 3a are joined to each other (the end 2a on the arrow C side is joined to the inner link plate 3a on the arrow C side, and the end 2a on the arrow D side is joined to the inner link plate 3a on the arrow D side. Yes.) The end 2a of the bush piece 20 joined to the inner link plate 3a is in a state of penetrating the inner link plate 3a.
[0019]
On the other hand, each outer link 6 has a pair of outer link plates 6a, 6a facing each other in the link axial direction (the direction of arrows C, D in FIG. 1), and these outer link plates 6a, 6a The pins 5 extending in the link axial direction connect the outer link plates 6a and 6a at the respective end portions (the end portion on the arrow A side and the end portion on the arrow B side) of both sides of the outer link plates 6a and 6a. It is joined and provided in the form. The inner link 3 and the outer link 6 configured as described above are connected by inserting the pin 5 of the outer link 6 into the bush 2 of the inner link 3 so as to be rotatable (that is, the two bush pieces constituting the bush 2). 20 and 20 is inserted into a pin 5 in a skewered manner), and the inner link 3 is inserted and disposed in the gap between the outer link plates 6a and 6a of the outer link 6. The bush pieces 20, 20 can be moved toward and away from each other in the directions of arrows C and D along the pin 5.
[0020]
Each outer link plate 6a of the outer link 6 has an inner surface 6b of the outer link plate 6a (that is, the outer link plate 6a on the arrow C side is a surface facing in the direction of arrow D, and the outer link plate on the arrow D side. 6a, an elastic sheet 7 made of a thin rubber sheet or the like is attached to the surface of the inner link 3 connected to the outer link 6 on the outer surface of the inner link plate 3a. On the surface 3b (that is, the surface facing the arrow C direction for the inner link plate 3a on the arrow C side, and the surface facing the arrow D direction for the inner link plate 3a on the arrow D side), facing the outer surface 3b Abuts against the elastic sheet 7 adhered to the inner surface 6b of the outer link plate 6a (the elastic sheet 7 is preliminarily attached to the inner link plate 3a during assembly). If you leave adhered to the outer link plate 6a assembly is easier.). In the present embodiment, the distance L1 between the inner link plate 3a and the outer link plate 6a sandwiching the elastic body sheet 7 (thus substantially equal to the thickness of the elastic body sheet 7) is that in a conventional chain without a seal ring. It is assumed that the size is approximately the same as the interval between the inner link plate and the outer link plate (interval L60 in FIG. 3).
[0021]
Each bushing piece 20 of the above-described bushing 2 has a tapered shape in which the inner diameter expands in the opening direction at the end 2a. Therefore, as shown in FIG. 1, the end 2a has a sharp cross section. It has a shape with. Further, as described above, since the end portion 2a penetrates the inner link plate 3a from the inside to the outside, a portion of the end portion 2a that protrudes through the inner link plate 3a has been bitten into the elastic sheet 7. It has become.
[0022]
Further, a roller 9 is rotatably fitted on the outer peripheral side of the bush 2 of each inner link 3, and the roller 9 has two bush pieces 20 constituting the bush 2 between the inner link plates 3a and 3a. , 20. Further, one seal ring 10 made of a rubber O-ring is inserted into each bush piece 20 of the bush 2 (therefore, a total of two seal rings 10, 10 are inserted into one bush 2. Each seal ring 10 abuts on the inner surface 3c (surface opposite to the outer surface 3b) of the inner link plate 3a joined to the bushing piece 20, and is inserted into the bushing 2. The roller 9 is disposed in contact with the opening end surfaces 9a on both sides (the end surface on the arrow C side and the end surface on the arrow D side). Each seal ring 10 is sandwiched between the inner link plate 3 a and the roller 9.
[0023]
In this embodiment, the roller 9 has a tapered shape in which each opening end face 9a is recessed on the inner peripheral side. Accordingly, the seal ring 10 in contact with the opening end surface 9a is pressed toward the inner side of the roller 9, and thus the bush 2 side, by the tapered surface of the opening end surface 9a. As a result, the roller 9 and the bush 2 are well sealed, and the seal ring 10 is held so that it does not accidentally drop off from the bush 2. As another example, a groove or a radius may be provided in the outer peripheral portion of the bush 2, the inner surface 3c of the inner link plate 3a, or the like, and the seal ring 10 may be more securely held by the groove or the radius. In addition, in the example of FIG. 1, the cross section of the seal ring 10 is circular. However, as another example, the cross section of the seal ring may be a square shape or an X shape.
[0024]
The seal chain 1 is configured as described above. Therefore, the end portion 2a of the bush 2 and the pin 5 are sealed by the elastic sheet 7, and the grease between the bush 2 and the pin 5 leaks from between the end portion 2a and the pin 5 to the outside. No foreign matter enters between the bush 2 and the pin 5 from the outside. In addition, since the edge part 2a of the bush 2 is tapering as mentioned above, it has digged into the elastic body sheet 7, and the sealing performance is further improved by this. Further, the grease between the bush 2 and the pin 5 enters between the bush 2 and the roller 9 via a clearance interval CL1 between the two bush pieces 20, 20 of the bush 2. The gap between the end face 9a and each bushing piece 20 is sealed by a seal ring 10, so that the grease does not leak from between the roller 9 and the bushing piece 20 to the outside, and foreign matter from outside the roller 9 and the bushing 2 There is no entry in between. As a result, the grease between the bush 2 and the pin 5 is retained, and wear prevention between the bush 2 and the pin 5 is guaranteed. Further, since the grease between the bush 2 and the roller 9 is also sealed and held, the wear prevention between the bush 2 and the roller 9 is also guaranteed. In particular, since the clearance interval CL1, which is a gap, is formed between the two bush pieces 20, 20, it is convenient to use this clearance interval CL1 to hold more grease. As another example, the clearance interval CL1 may be filled with an elastic member, or the bush pieces 20 and 20 are connected to each other in a sheath tube so as to be able to approach and retract, and thus the clearance interval CL1 is not formed. You may do it.
[0025]
Further, in this seal chain 1, when the chain vibrates laterally or there is a sprocket offset or the like, the outer link plate 6a and the inner link plate 3a sandwiching the elastic body sheet 7 try to approach and retract each other. The pair of inner link plates 3a, 3a uses the approaching / retreating operation of the bushing pieces 20, 20 connecting them in the directions of arrows C, D, and outward with respect to the roller 9 by the seal rings 10, 10. By being pressed, the outer link plates 6a and 6a move so as to follow the outer link plates 6a and 6a while maintaining a constant distance L1 between the outer link plates 6a and 6a. Therefore, the seal between the bush 2 and the pin 5 by the elastic sheet 7 is maintained well. As a result, grease leakage and the like are prevented, wear prevention between the bush 2 and the pin 5 or between the bush 2 and the roller 9 is guaranteed, and an excellent seal chain 1 with high wear resistance is provided. Further, in the conventional seal chain 50 (FIG. 2), in order to ensure the sealing effect by the seal ring 56 between the inner link plate 52a and the outer link plate 55a, the interval L50 between the inner and outer link plates 52a, 55a is set. Although the sealing member has sufficient elastic performance so that it can be deformed in response to the change, in this embodiment, the sealing effect by the elastic sheet 7 between the inner link plate 3a and the outer link plate 6a is And the outer link plates 3a, 6a depend on each other and do not depend on the elastic performance of the elastic sheet 7, so that the elastic sheet 7 is thinned accordingly, and the inner and outer link plates 3a, The distance L1 between 6a can be narrower than that of the conventional seal chain. Further, in this embodiment, in order to secure the sealing effect by the elastic sheet 7, the seal ring 10 is provided with elastic performance so that the inner link plate 3a can be pressed against the outer link plate 6a. 10 is arranged between the pair of inner link plates 3a, 3a. However, the width of the roller 9 in the link axial direction is slightly reduced by the amount corresponding to the seal ring 10, so that the inner link 3 is configured with a width approximately equal to the inner link width in a conventional chain (a chain that is not a seal chain). . As described above, in the seal chain 1, it is not necessary to make the width of the chain, and thus the length of the pin 5 etc., particularly longer than that of a conventional chain (a chain that is not a seal chain). In addition, since the length of the pin 5 does not need to be increased, the rigidity and strength of the pin 5 are not lowered correspondingly, so that the seal chain 1 having appropriate rigidity and strength is obtained. In addition, since it is not necessary to make the cross section of the seal ring 10 particularly small, it is not necessary to increase the accuracy and assembly accuracy of each part, and the manufacturing is easy and the cost is not increased.
[0026]
Further, since the clearance interval CL1 is formed between the bush pieces 20 and 20 so that the inside and outside of the bush 2 are communicated with each other, the bush pieces 20 and 20 can be smoothly approached and retracted, which is advantageous. Further, it is convenient because the weight of the entire chain is reduced by the clearance clearance CL1. The bush pieces 20, 20 are connected by a pair of inner link plates 3 a, 3 a connected by them, and seal rings 10, 10 that press the inner link plates 3 a, 3 a against the roller 9 in the outward direction. Since they are pressed in the direction of retreating from each other, the end portions facing each other through the clearance interval CL1 do not collide to generate noise.
[0027]
In the above-described embodiment, the elastic sheet 7 has a shape that is almost perfectly fitted to the outer link plate 6a. However, the elastic sheet 7 may have any shape as long as it surrounds at least the periphery of the pin 5. For example, it may be circular (in this case, a total of two elastic sheets are required for each pin 5 on one outer link plate 6a).
[Brief description of the drawings]
FIG. 1 is a plan view (a partial cross-sectional view) showing an example of a seal chain according to the present invention.
FIG. 2 is a plan view (a partial cross-sectional view) showing an example of a conventional general seal chain.
FIG. 3 is a plan view (a partial cross-sectional view) showing an example of a conventional chain having no seal ring.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Seal chain 2 Bush 3 Inner link 3a Inner link plate 5 Pin 6 Outer link 6a Outer link plate 7 First seal member (elastic body sheet)
9 Roller 9a Opening end face 10 Seal ring 20 First bush piece, second bush piece (bush piece)
CL1 clearance interval

Claims (3)

An inner link having a bush and a pair of inner link plates fitting the bush to both ends thereof, and an outer link having a pin and a pair of outer link plates connected to each other via the pins, The pair of inner link plates are inserted and arranged inside the pair of outer link plates, and the pins are rotatably inserted and connected to the bushes, so that rollers can rotate on the outer periphery of the bushes. In the seal chain provided by insertion,
A first seal member is interposed between each inner link plate and the outer link plate disposed outside the inner link plate, and the first seal member is sandwiched between the inner link plate and the outer link plate. Provided in a shape that surrounds the periphery of the pin by the first seal member;
The bush includes a first bushing piece provided on one inner link plate and a second bushing piece provided on the other inner link plate of the pair of inner link plates. It has a shape that can be moved toward and away from each other along the fitted pins,
A seal chain comprising a seal ring inserted and provided on the outer periphery of the first and second bush pieces between the pair of inner link plates and the roller. 2. The seal chain according to claim 1, wherein a clearance is formed between the first bushing piece and the second bushing piece so that the inside and outside of the bush are in communication with each other. 2. The seal chain according to claim 1, wherein the opening end faces on both sides of the roller are tapered with an inner peripheral side recessed.

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