HK1159219B - Seal chain - Google Patents

Abstract

There is provided a seal chain capable of maintaining a high sealing function for a long period of time and of exhibiting excellent chain strength by decreasing wear of sealing mechanism, inner and outer plates and other. A sealing mechanism (130) has a first seal member (131) provided while contacting with an inner plate (111), a second seal member (132) disposed so as to face to the first seal member (131) and provided while contacting with an outer plate (121), the first seal member (131) has a pair of lips (131a) formed annularly on the surface of the side facing to the second seal member (132), and the second seal member (132) has a sliding surface (132b) that contacts and slides with the pair of lips (131a) formed on the first seal member (131) on the side facing to the first seal member (131).

Description

Sealing chain

Technical Field

The present invention relates to a seal chain in which a seal mechanism is provided between an inner plate and an outer plate, and which prevents a lubricant (e.g., lubricating oil, grease, solid lubricant, etc.) sealed in a bearing portion formed by an outer peripheral surface of a pin and an inner peripheral surface of a bushing from leaking to the outside and prevents the intrusion of foreign matter (e.g., dust, etc.) from the outside.

Background

Heretofore, as a transmission and conveyance device used in an environment with a large amount of dust, a seal chain has been used, which is a seal mechanism disposed between an inner plate and an outer plate, and which prevents a lubricant such as grease sealed in a bearing portion constituted by an inner peripheral surface of a bush and an outer peripheral surface of a pin from leaking to the outside and prevents intrusion of foreign matter from the outside.

Further, as such a sealing mechanism, an annular elastic sealing member similar to an O-ring has been generally used heretofore, and further, in order to improve a sealing function, another sealing mechanism has been proposed (first prior art, refer to patent document 1) in which a pair of annular sealing members 531, 532 are disposed so as to face each other between facing surfaces of an inner plate 511 and an outer plate 521, the pair of annular sealing members 531, 532 have annular lip-shaped convex portions 531a, 532a and annular concave portions 531b, 532b on the facing surfaces, end portions of the annular lip-shaped convex portions 531a, 532a are pressed against bottom portions of the annular concave portions 531b, 532b by elasticity of the pair of annular sealing members 531, 532, and when the seal chain is bent, the end portions of the annular lip-shaped convex portions 531a, 532a slide against the bottom portions of the annular concave portions 531b, 532b.

Another sealing mechanism has been proposed (second prior art, see patent document 2), which includes: a steel annular seal receiving member 632 which is fitted and fixed to the pin 622, abuts against the inner surface of the outer plate 621, and has a disc-shaped seal receiving portion 632a interposed between the end surface of the bush 612 and the inner surface of the outer plate 621, and a rim-shaped seal receiving portion 632b which bulges toward the inner plate 611 on the outer peripheral side; a first elastic seal ring 631 fitted around the outer peripheral surface of the bush 612 protruding from a part of the outer surface of the inner plate 611 and interposed between the annular seal receiving member 632 and the inner plate 611; a steel seal ring 633 disposed outside the annular seal receiving member 632 and in contact with the outer surface of the inner plate 611; the second elastic seal ring 634 is interposed between the inner peripheral surface of the steel seal ring 633 and the outer peripheral surface of the rim-shaped seal receiving portion 632b of the annular seal receiving member 632.

Patent document 1: japanese unexamined patent application publication No. 2005-76681

Patent document 2: japanese laid-open patent publication No. 2008-157423

Disclosure of Invention

However, in the sealing mechanism 530 according to the first conventional technique, since the number of components is large, or when the lip-shaped convex portions 531a and 532a are inserted into the concave portions 531b and 532b, it takes time and labor to adjust the mutual positions of the pair of annular sealing members 531 and 532, there is a problem that the work efficiency is not high, and there is a problem that the position of the sealing member disposed on the outer peripheral side is unstable, and there is a possibility that a lubricant such as grease to be enclosed leaks.

In the sealing mechanism according to the second conventional technique, the annular seal receiving member 632 is pressed against the inner surface of the outer plate 621 by the second elastic seal ring 634 such as an O-ring, but since the second elastic seal ring 634 is not fixed to the annular seal receiving member 632 or the steel seal ring 633 by an adhesive or the like, for example, when lubricant adheres to the periphery of the second elastic seal ring 634, the second elastic seal ring 634 slides relative to the annular seal receiving member 632 or the steel seal ring 633, and the second elastic seal ring 634 is worn, thereby degrading the sealing performance.

Further, the steel annular seal receiving member 632 slides while being pressed against the inner surface of the outer panel 621, and may abrade the inner surface of the outer panel 621, thereby reducing the strength of the outer panel 621.

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a seal chain which can exhibit excellent chain strength while suppressing wear of a seal mechanism, an inner plate, an outer plate, and the like, while maintaining high sealing performance for a long period of time.

A seal chain according to the invention of claim 1, including an inner chain configured by protruding both end portions of a pair of bushings and press-fitting the both end portions into a pair of inner plates, an outer chain configured by press-fitting both end portions of two pins slidably fitted into the bushings of two inner chains adjacent in the front and rear direction into a pair of outer plates, and a seal mechanism disposed between the inner plates and the outer plates; wherein the sealing mechanism has a first sealing member provided in contact with an outer surface of the inner panel facing the outer panel, and a second sealing member disposed facing the first sealing member and provided in contact with an inner surface of the outer panel facing the inner panel; the first seal member has a pair of lips formed annularly on a face on the opposite side from the second seal member; the second seal member has a sliding surface for sliding the pair of lips formed on the first seal member in contact with the side opposite to the first seal member, thereby solving the above-described problem.

In the seal chain according to the invention of claim 2, in the structure of the invention of claim 1, the first seal member has a first annular groove on a surface abutting against the inner plate, the second seal member has a second annular groove on a surface abutting against the outer plate, the first annular groove and the second annular groove are filled with a lubricant, the first seal member is in close contact with an outer surface of the inner plate, and the second seal member is in close contact with an inner surface of the outer plate, thereby solving the problem.

In the seal chain according to the invention of claim 3, in the structure of the invention of claim 1 or 2, the first seal member or the second seal member is formed of an elastomer synthetic resin material, thereby solving the above-described problem.

In the seal chain according to the invention of claim 4, in the structure of the invention according to any one of claims 1 to 3, the second seal member has an annular wall at an outer peripheral portion thereof at a height slightly closing a gap between the outer plate and the inner plate, thereby solving the problem.

In the seal chain according to the invention of claim 5, in the structure according to any one of claims 1 to 4, the first seal member is press-fitted and fixed to an end portion of the bushing, thereby solving the above-described problem.

In the seal chain according to the invention of claim 6, in the structure of any one of claims 1 to 5, the annular seal ring integrally formed on the outer peripheral portion of the second seal member is press-fitted and fixed to the fitting groove provided on the inner surface of the outer plate, thereby solving the above-described problem.

In the seal chain according to the invention of claim 7, in the structure according to any one of claims 1 to 6, the sliding surface of the second seal member has a projection formed in an annular shape facing between the pair of lips formed on the first seal member, and the seal mechanism has a labyrinth structure formed by the pair of lips formed on the first seal member and the projection formed on the second seal member, thereby solving the above-described problem.

In the seal chain according to the invention of claim 8, in the structure according to any one of claims 1 to 7, the diameter of the outer peripheral side end surface of the first seal member is increased toward the inner plate, and the outer peripheral side end surface of the first seal member abuts against the outer side surface of the inner plate at an acute angle, thereby solving the problem.

In the seal chain according to the invention of claim 9, in the structure according to any one of claims 1 to 8, the diameter of the inner circumferential end surface of the second seal member is increased toward the outer plate, and the second seal member abuts against the inner side surface of the outer plate at an acute angle, thereby solving the above-described problem.

The seal chain of the present invention includes an inner chain formed by protruding both end portions of a pair of bushings and press-fitting them into a pair of inner plates, an outer chain formed by press-fitting both end portions of two pins slidably fitted into the bushings of two inner chains adjacent to each other in the front-rear direction into a pair of outer plates, and a seal mechanism disposed between the inner plates and the outer plates, and therefore, it is possible to seal a lubricant filled in a bearing portion formed by an inner peripheral surface of the bushing and an outer peripheral surface of the pin, and the present invention has the following characteristic effects.

That is, according to the seal chain of the invention according to claim 1, the seal mechanism includes the first seal member provided in contact with the outer side surface of the inner plate facing the outer plate, and the second seal member disposed to face the first seal member and provided in contact with the inner side surface of the outer plate facing the inner plate, the first seal member includes a pair of lips annularly formed on a surface facing the second seal member, and the second seal member includes a sliding surface which slides the pair of lips formed on the first seal member in contact with the side facing the first seal member. Therefore, only by the lip portion formed on the first seal member sliding against the sliding surface of the second seal member, the possibility of the inner plate and the first seal member or the outer plate and the second seal member sliding against each other is greatly reduced, and the wear of the outer plate and the inner plate is significantly reduced, so that the strength of the chain is not reduced, and the life of the entire chain can be extended.

Further, the position where the pair of lips formed on the first seal member abut is not the groove provided in the first conventional art, but a planar sliding surface formed on the second seal member, so that the position adjustment between the first seal member and the second seal member is facilitated, and the work efficiency at the time of assembly can be improved.

In the seal chain according to the invention of claim 2, in addition to the effect of the invention of claim 1, the first seal member has a first annular groove on a surface abutting against the inner plate, the second seal member has a second annular groove on a surface abutting against the outer plate, the first annular groove and the second annular groove are filled with a lubricant, the first seal member is in close contact with an outer surface of the inner plate, and the second seal member is in close contact with an inner surface of the outer plate. Therefore, after the gas is exhausted from the two annular grooves, the adhesion between each plate and each seal member is improved, and the possibility of occurrence of sliding between the inner plate and the first seal member or sliding between the outer plate and the second seal member is further reduced.

According to the seal chain of the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, since the first seal member or the second seal member is formed of the synthetic resin material of the elastic body, it is not necessary to provide a separate pressing member as compared with the case of using a rigid seal member, and therefore the number of components is reduced, the work efficiency is improved, and the cost can be reduced.

According to the seal chain of the invention of claim 4, in addition to the effect of the invention described in any one of claims 1 to 3, since the second seal member has the annular wall at the outer peripheral portion thereof at a height that slightly closes the gap between the outer plate and the inner plate, the annular wall can prevent the lubricant sealed in the bearing portion formed by the inner peripheral surface of the bushing and the outer peripheral surface of the pin from leaking to the outside, and can prevent foreign matter such as particulate matter from entering the inside of the seal mechanism from the outside, thereby preventing damage to the first seal member, the second seal member, and the like disposed inside.

According to the seal chain of the invention of claim 5, in addition to the effect of the invention of any one of claims 1 to 4, since the first seal member is press-fitted and fixed to the end portion of the bushing, the first seal member is stably fixed to the outer surface of the inner panel, and relative movement between the inner panel press-fitted and fixed to the bushing and the first seal member can be favorably prevented, so that abrasion of the inner panel can be prevented, a decrease in the strength of the chain can be prevented, and the life of the chain can be extended.

According to the seal chain of the invention of claim 6, in addition to the effect of the invention of any one of claims 1 to 5, the annular seal ring integrally formed on the outer peripheral portion of the second seal member is press-fitted and fixed into the fitting groove provided on the inner side surface of the outer plate, so that the second seal member is stably fixed to the inner side surface of the outer plate, and sliding between the outer plate and the second seal member can be favorably prevented, whereby abrasion of the outer plate can be prevented, a decrease in the strength of the chain can be prevented, and the life of the chain can be extended.

According to the seal chain of the invention of claim 7, in addition to the effect of the invention of any one of claims 1 to 6, the sliding surface of the second seal member has a projection formed in an annular shape facing between the pair of lips formed on the first seal member, and the seal mechanism has a labyrinth structure formed by the pair of lips formed on the first seal member and the projection formed on the second seal member, so that the labyrinth structure can prevent the lubricant sealed in the bearing portion formed by the inner peripheral surface of the bushing and the outer peripheral surface of the pin from leaking to the outside and prevent the foreign matter from entering the inside of the seal mechanism.

According to the seal chain of the invention of claim 8, in addition to the effect of the invention of any one of claims 1 to 7, since the outer peripheral side end surface of the first seal member is larger in diameter as it approaches the inner plate and comes into contact with the outer side surface of the inner plate at an acute angle, when foreign matter entering from the outside presses the outer peripheral side end surface of the first seal member, the outer peripheral side end surface of the first seal member is pressed and brought into closer contact with the outer side surface of the inner plate, and therefore, the foreign matter can be prevented from entering the inside of the first seal member.

According to the seal chain of the invention of claim 9, in addition to the effect of the invention of any one of claims 1 to 8, since the inner circumferential end surface of the second seal member has a larger diameter as it approaches the outer plate and comes into contact with the inner side surface of the outer plate at an acute angle, when the lubricant sealed in the bearing portion constituted by the inner circumferential surface of the bush and the outer circumferential surface of the pin is pressed against the inner side surface of the outer plate due to a certain force, the inner circumferential end surface of the second seal member is pressed further, and therefore, the lubricant can be prevented from entering the inside of the second seal member and leaking to the outside.

Drawings

Fig. 1 is a schematic view of a sealing chain according to a first embodiment of the present invention;

FIG. 2 is a cross-sectional view of the sealing chain shown in FIG. 1;

FIG. 3 is an enlarged cross-sectional view of a key portion of the seal chain shown in FIG. 2;

fig. 4 is an enlarged sectional view of a key part of a seal chain according to a second embodiment of the present invention;

fig. 5 is an enlarged sectional view of a key part of a first prior art seal chain;

fig. 6 is an enlarged sectional view of a key part of a second prior art seal chain.

Description of the symbols:

100. 200

110. Inner chain 210

111. Inner plate

111a, 211a

112. 212

120. Outer chain (220)

121. An outer panel

121a, 221a

121b, 221b

122. Pin of 222

122a, 222a

122b, 222b

122c, 222c

122d, 222d

130. Sealing mechanism

131. A first seal member

131a, 231a

131b, 231b

131c, 231c

132. A second sealing member

132a, 232a

132b, 232b

132c, 232c

132d, 232d

132e, 232e

133. 233

511. 611

512. A bushing

521. 621. outer panel

521. Pin 622

522. 532

531a, 532a

531b, 532b

631.. a first elastomeric seal ring

632. annular seal receiving member

632a

632b

A steel seal ring

A second elastomeric seal ring

Detailed Description

The seal chain of the present invention includes an inner chain configured by projecting both end portions of a pair of bushings and press-fitting them into a pair of inner plates, an outer chain configured by press-fitting both end portions of two pins slidably fitted into the bushings of two inner chains adjacent in the front and rear direction into a pair of outer plates, and a seal mechanism disposed between the inner plates and the outer plates, wherein the seal mechanism includes a first seal member provided in contact with an outer side surface of the inner plates facing the outer plates, and a second seal member provided in contact with the first seal member and provided in contact with an inner side surface of the outer plates facing the inner plates, the first seal member includes a pair of lips annularly formed on a surface facing the second seal member, and the second seal member includes a sliding surface configured to slide the pair of lips formed on the first seal member in contact with a side facing the first seal member, therefore, while maintaining high sealing performance for a long period of use, abrasion of the sealing mechanism and the inner and outer plates is suppressed, and excellent chain strength is exhibited, and the specific embodiment thereof may be any as long as the above conditions are satisfied.

That is, the chain itself constituting the seal chain may be a roller chain in which rollers are externally fitted to bushings or a bushing chain as long as the seal mechanism can be disposed between the inner plate and the outer plate.

The first annular groove formed in the first seal member and the second annular groove formed in the second seal member are each a groove formed in a plurality of concentric circles, and the number thereof may be determined as appropriate in consideration of the size of the seal chain, the properties of the lubricant to be filled, and the like.

The first seal member and the second seal member are molded from an elastomer synthetic resin material, and as the synthetic resin material, it is preferable to use rubbers such as nitrile rubber (NBR), urethane rubber (polyurethane), chloroprene rubber, and fluorinated rubber (6-fluoropropylene-vinylidene fluoride copolymer) in consideration of abrasion resistance, oil resistance, heat resistance, and the like.

Further, the lip portion may have various shapes, and preferably has a triangular cross section or an arc cross section having an acute angle at an end portion thereof which comes into contact with a sliding surface formed on the first seal member, and thus has excellent durability and sealing effect.

In view of abrasion resistance, it is preferable that the first seal member forming the lip is made of a relatively hard material such as urethane rubber as compared with the second seal member in which the lip abuts and slides, and the second seal member having the sliding surface is made of a relatively soft material such as NBR rubber.

When the annular seal ring and the second seal member are integrally formed, any fixing means may be used as long as they are not loosened and can be firmly fixed, but a simple method of sintering or adhesive is preferably used.

Examples

Next, an embodiment of the present invention will be described with reference to fig. 1 to 4, where fig. 1 is a schematic view of a seal chain according to a first embodiment of the present invention, fig. 2 is a sectional view of the seal chain shown in fig. 1, fig. 3 is an enlarged sectional view of a main portion of the seal chain shown in fig. 2, and fig. 4 is an enlarged sectional view of a main portion of the seal chain according to a second embodiment of the present invention.

As shown in fig. 1 to 3, the seal chain 100 according to the first embodiment is formed by interconnecting an inner chain 110 and an outer chain 120, the inner chain 110 includes a pair of inner plates 111 spaced apart from each other in a direction orthogonal to the chain longitudinal direction, a pair of cylindrical bushings 112 press-fitted into the inner plates 111 and having both end portions thereof protruding, and rollers 113 slidably fitted into the bushings 112, and the outer chain 120 includes a pair of outer plates 121 spaced apart from each other in a direction orthogonal to the chain longitudinal direction outside the pair of inner plates 111, and pins 122 slidably fitted into the bushings 112 and press-fitted into the pair of outer plates 121. Further, a seal mechanism 130 is disposed between the inner plate 111 and the outer plate 121, that is, between the outer surface 111a of the inner plate 111 and the inner surface 121a of the outer plate 121.

As shown in fig. 2, the pin 122 has oil passages 122a and 122b inside and a groove 122c on the outer peripheral surface communicating with the oil passage 122b, and lubricant (grease, engine oil, or the like) is supplied from one end 122d of the pin 122 to a bearing portion formed by the inner peripheral surface of the bushing 112 and the outer peripheral surface of the pin 122 through the oil passages 122a and 122b and the groove 122 c.

However, the outer circumferential groove 122c without the pin 122 may be provided as needed.

As shown in fig. 2, the seal mechanism 130 is constituted by a first seal member 131 press-fitted to an end portion of the bushing 112 and a second seal member 132 integrally sintered with a seal ring 133 press-fitted and fixed to the inner surface 121a of the outer plate 121.

However, the seal ring 133 is not essential, and other methods may be used as long as the second seal member 132 is attached to the inner surface 121a of the outer panel by some method.

Further, a pair of triangular lips 131a having distal end portions directed radially outward are annularly formed on the surfaces of the first seal member 131 and the second seal member 132 facing each other, and two grooves, i.e., first annular grooves 131b are concentrically formed on the surface of the first seal member 131 in contact with the inner panel 111.

When the first seal member 131 is attached, the first annular groove 131b is filled with a lubricant such as grease.

In this way, when the first seal member 131 is attached to the bush 112, the inner peripheral portion of the first seal member 131 is pressed into the bush 112, and the first seal member 131 is pressed against the outer surface 111a of the inner panel 111, and then air between the inner panel 111 and the first seal member 131 is removed by the grease filled in the first annular groove 131b, so that the inner panel 111 and the first seal member 131 are attached in a highly tight state, and therefore, sliding between them can be prevented.

A sliding surface 132b that slides in contact with a lip 131a formed annularly on the first seal member 131 is formed on a surface of the second seal member 132 facing the first seal member 131, and an annular protrusion 132a is formed on the sliding surface 132b, between a pair of lips 131a formed on the first seal member 131, so as to protrude toward the first seal member.

Two grooves, i.e., a second annular groove 132c, are formed concentrically on the surface of the second seal member 132 that contacts the outer plate 121.

When the second seal member 132 is attached, the second annular groove 132c is filled with a lubricant such as grease in advance, as with the 1 st annular groove 131b, and the second seal member 132 is pressed against the inner surface 121a of the outer plate 121 while the seal ring 133 is pressed into the fitting groove 121b formed in the inner surface 121a of the outer plate 121.

In this way, the air between the outer plate 121 and the second seal member 132 is removed by the filled grease, and the outer plate 121 and the second seal member 132 are attached in a highly tight state, so that the sliding between the two can be prevented.

Further, an annular wall 132d having a height slightly closing a gap between the inner plate 111 and the outer plate is formed on the outer periphery of the second seal member 132. The annular wall 132d can prevent the lubricant sealed in the bearing portion formed by the inner peripheral surface of the bushing 112 and the outer peripheral surface of the pin 122 from leaking to the outside.

Further, the first seal member 131 is made of a polyurethane seal material, and the second seal member 132 is made of NBR, but other synthetic resin materials may be used as long as the required elasticity and abrasion resistance can be secured.

In addition, when these elastic sealing members are used, after the sealing mechanism is mounted, the two sealing members are pressed to deform the lip portion 131a and the like, and the respective sealing members are pressed by the respective plates by reaction forces caused by the deformation of the elastic sealing members, so that the adhesion between the sealing members and the plates can be improved.

Further, the second seal member 132 is integrally sintered with the seal ring 133 located outside the annular wall 132d, and if the seal ring 133 is made of a hard material such as steel, even if the chain is used in an environment where dust or the like exists around, the dust is blocked by the seal ring 133, and the seal members inside the seal mechanism 130 can be prevented from being damaged by the dust.

In the seal chain 100 according to the first embodiment of the present invention, the first seal member 131 is provided in contact with the outer side surface 111a of the inner plate 111 facing the outer plate 121, the second seal member 132 is provided in contact with the inner side surface 121a of the outer plate 121 disposed facing the first seal member 131 and located on the inner side surface facing the inner plate 111, and the first seal member 131 has the pair of annular lips 131a formed on the surface facing the second seal member 132, and the second seal member 132 has the sliding surface 132b which slides in contact with the pair of lips 131a formed on the first seal member 131 on the surface facing the first seal member 131.

Further, since the material of the first seal member 131 and the second seal member 132 is an elastomer, the sealing property, that is, the sealing property can be improved, and a lubricant having high fluidity can be used, the lip portion 131a of the first seal member 131 and the sliding surface 132b of the second seal member 132 slide with an oil film formed therebetween, and as a result, the wear of the two seal members can be reduced, and the life of the seal members can be extended.

Further, the protrusion 132a formed on the second seal member 132 and the lip 131a formed on the first seal member 131 have a labyrinth structure which prevents leakage of the lubricant sealed in the bearing portion formed by the inner peripheral surface of the bush and the outer peripheral surface of the pin to the outside and intrusion of foreign objects, and if the lip formed on the first seal member is worn to some extent, the labyrinth structure prevents leakage of the lubricant, and has a simple structure, easy production, and a great effect.

Hereinafter, a second embodiment of the present invention will be described with reference to fig. 4.

Since the second embodiment is different from the first embodiment in the shape of the end portions of the first seal member and the second seal member and the other specific structures are the same, 200-series numbers are assigned to the same members as those of the seal chain 100 according to the first embodiment, and redundant description is omitted.

Fig. 4 is an enlarged cross-sectional view of a key portion of the same seal chain as that shown in fig. 1 of the first embodiment, showing a second embodiment of the present invention.

As shown in fig. 4, in the sealing mechanism 230 according to the present embodiment, the outer peripheral end surface 231c is formed so that the outer peripheral end portion of the first sealing member 231 has a larger diameter as it approaches the inner plate 211 and comes into contact with the outer surface 211a of the inner plate 211 at an acute angle.

Thus, when a foreign object intruding from the outside collides with the outer peripheral end surface 231c, the pressing force applied to the outer peripheral end surface 231c by the foreign object acts in the direction of pressing the first seal member 231 against the outer side surface 211a of the inner panel 211, and when the foreign object intrudes, the adhesion between the first seal member 231 and the outer side surface 211a of the inner panel 211 is further improved.

As shown in fig. 4, an inner peripheral side end surface 232e is formed so that the inner peripheral side end of the second seal member 232 has a larger diameter as it approaches the outer panel 221, and comes into contact with the inner side surface 121a of the outer panel 221 at an acute angle.

As described above, when the lubricant sealed in the bearing portion constituted by the inner peripheral surface of the bushing 212 and the outer peripheral surface of the pin 222 is increased in internal pressure by some force, the inner peripheral side end surface 232e of the second seal member 232 is further pressed and brought into close contact with the inner side surface 221a of the outer plate 221.

According to the seal chain 200 of the second embodiment of the present invention, the first seal member 231 is provided in contact with the outer side surface of the inner plate 211 facing the outer plate 221, the second seal member 232 is provided in contact with the inner side surface 221a of the outer plate 221 disposed facing the first seal member and located on the inner plate 211 facing surface, and the first seal member 231 has the pair of annular lips 231a formed on the surface facing the second seal member 232, and the second seal member 232 has the sliding surface 232b which slides in contact with the pair of lips 231a formed on the first seal member 231 on the surface facing the first seal member 231.

Further, by forming the outer peripheral end surface 231c in the shape described above, when foreign matter intrudes, the adhesion between the first seal member 231 and the outer side surface 211a of the inner panel 211 is further improved, and it is possible to prevent the foreign matter from intruding between the first seal member 231 and the inner side surface 211a of the inner panel 211, and to maintain the performance of the first seal member 231 for a long period of time.

Further, by forming the inner circumferential side end surface 232e of the second seal member 232 as described above, the adhesion between the inner circumferential side end surface 232e of the second seal member 232 and the outer plate 221 is further improved, and the lubricating performance of the bearing portion constituted by the inner circumferential surface of the bush and the outer circumferential surface of the pin can be maintained for a long period of time, which has a great effect.

Claims (9)

1. A sealing chain, characterized by comprising: an inner chain configured by protruding both end portions of a pair of bushings and press-fitting the bushings into a pair of inner plates, an outer chain configured by press-fitting both end portions of two pins slidably fitted into the bushings of two inner chains adjacent in the front and rear direction into a pair of outer plates, and a seal mechanism disposed between the inner plates and the outer plates;

the sealing mechanism comprises a first sealing component which is arranged on the outer side surface of the inner plate opposite to the outer plate in an abutting mode, and a second sealing component which is arranged opposite to the first sealing component and arranged on the inner side surface of the outer plate opposite to the inner plate in an abutting mode;

the first seal member has a pair of lips formed annularly on a face on the opposite side from the second seal member;

the second seal member has a sliding surface which causes a pair of lips formed on the first seal member to abut against and slide on a side opposite to the first seal member;

wherein: the first seal member has a first annular groove on a surface abutting against the inner plate, the second seal member has a second annular groove on a surface abutting against the outer plate, the first annular groove and the second annular groove are filled with a lubricant, the first seal member is in close contact with an outer side surface of the inner plate, and the second seal member is in close contact with an inner side surface of the outer plate.

2. The sealing chain according to claim 1, wherein: the first seal member or the second seal member is formed of an elastomer synthetic resin material.

3. The sealing chain according to claim 1, wherein: the second seal member has an annular wall at an outer peripheral portion thereof at a height slightly closing a gap between the outer plate and the inner plate.

4. The sealing chain according to claim 2, wherein: the second seal member has an annular wall at an outer peripheral portion thereof at a height slightly closing a gap between the outer plate and the inner plate.

5. The sealing chain according to any one of claims 1 to 4, wherein: the first seal member is press-fitted and fixed to an end portion of the bushing.

6. The sealing chain according to any one of claims 1 to 4, wherein: an annular seal ring integrally formed on an outer peripheral portion of the second seal member is press-fitted and fixed into a fitting groove provided on an inner side surface of the outer panel.

7. The sealing chain according to any one of claims 1 to 4, wherein: the sliding surface of the second seal member has a projection formed in an annular shape facing between the pair of lips formed on the first seal member;

meanwhile, the sealing mechanism forms a labyrinth structure by a pair of lips formed on the first sealing member and a protrusion formed on the second sealing member.

8. The sealing chain according to any one of claims 1 to 4, wherein: the outer peripheral side end surface of the first seal member has a larger diameter closer to the inner plate and is brought into contact with the outer side surface of the inner plate at an acute angle.

9. The sealing chain according to any one of claims 1 to 4, wherein: the second seal member has an inner peripheral side end surface that is larger in diameter as it approaches the outer plate and that makes an acute-angle contact with the inner side surface of the outer plate.