CN111664223B

CN111664223B - Sealing chain

Info

Publication number: CN111664223B
Application number: CN202010146830.0A
Authority: CN
Inventors: 林航平
Original assignee: Daido Kogyo Co Ltd
Current assignee: Daido Kogyo Co Ltd
Priority date: 2019-03-08
Filing date: 2020-03-05
Publication date: 2023-11-24
Anticipated expiration: 2040-03-05
Also published as: CN111664223A; JP7308626B2; JP2020143765A

Abstract

The seal chain of the present invention comprises: outer links that fix the pin to both end portions of the pair of outer plates; an inner link that is coupled to the outer link by press-fitting a bush into bush holes formed in a pair of inner plates and inserting the pin into the bush; and a seal ring for sealing lubricating oil interposed between the pin and the sleeve. The inner side surface of the outer plate is formed as a flat surface, the outer side surface of the inner plate has a recess concentric with the sleeve hole, and the seal ring is accommodated in the recess and is held so as to have a predetermined gap between the inner side surface of the outer plate and the outer side surface of the inner plate.

Description

Sealing chain

Technical Field

The present invention relates to a chain such as a roller chain, and more particularly, to a seal chain in which a seal ring for holding lubricating oil on a sliding surface between a pin and a bush is sandwiched between an inner plate and an outer plate.

Background

Conventionally, as shown in fig. 8, a seal chain 1 is configured by a roller chain in which a pin 3 is inserted into a bush 7 and an outer link 5 and an inner link 10 are alternately and jointlessly connected to each other, wherein the outer link 5 is configured by pressing the pin 3 into both end portions of a pair of outer plates 2 and fixing both ends of the pin by caulking or the like, and the inner link 10 is configured by pressing and fixing the bush 7 into both end portions of a pair of inner plates 6 and loosely inserting a roller 9 into the bush 7 between the inner plates 6, such that both end portions of the bush 7 protrude from the outer side surfaces 6a of the inner plates 6 to surround the bush protruding portions 7a, as a basic structure.

The seal chain 1 seals the lubricating oil sealed between the pin 3 and the sleeve 7 by the seal ring 11, and the relative movement between the pin 3 and the sleeve 7 is smoothed, so that the bending of the seal chain 1 is maintained smooth for a long period of time. At this time, the sleeve protrusion 7a restricts the clearance between the inner plate 6 and the outer plate 2, and restricts the compression allowance of the seal ring 11 sandwiched between the two plates 6 and 2, thereby preventing the seal ring 11 from excessively being deformed by compression and from being worn out too early, and further preventing breakage.

However, in the seal chain 1, since the seal ring 11 is sandwiched between the outer side surface 6a of the inner plate 6 having the flat surface and the inner side surface 2a of the outer plate 2 having the flat surface formed thereon, the gap between the two plates 2, 6 is enlarged, and the gap between the pair of outer plates 2, 2 is enlarged, so that the bending moment of the pin 3 fixed to the outer plates is increased. As a result, although shown in fig. 8 with a strong force, the pin 3 is elastically deformed and elastically deformed so that the outer plate expands outward, and the fatigue strength of the chain is lowered, and the pin 3 is separated from the outer plate 2, and the tensile strength of the chain tends to be lowered.

Further, since the outer panel 2 is expanded outward, the seal ring 11 is caught between the sleeve projecting portion 7a and the inner side surface 2a of the outer panel 2 on the outer side in the longitudinal direction of the outer panel 2, and the seal ring 11 is excessively pressed and deformed on the inner side in the longitudinal direction of the outer panel 2, and the like, which causes an unstable compression margin of the seal ring, and an unnatural force acts on the seal ring, which causes an obstacle to a correct seal function. Thereby, smooth operation of the seal chain is hindered, and the life of the seal chain may be shortened.

The sleeve 7 is formed by winding a plate-like member, cutting a round rod material, or cutting a tube material. Therefore, the seal ring may be damaged by the end face of the sleeve protruding portion 7a, particularly, the end face thereof, because the accuracy of the end face is not high.

Conventionally, as shown in japanese patent application laid-open No. 2018-179121, a seal chain (roller chain) has been proposed in which a concave portion concentric with a pin hole is formed on an inner surface side of an outer plate, a convex portion is formed on an outer surface side, and a sleeve projecting portion is accommodated in the concave portion together with a seal ring (refer to patent document 1).

In the seal chain of japanese patent application laid-open No. 2018-179121, the sleeve projecting portion and the seal ring are accommodated in the recess portion, so that the interval (gap) between the outer plate and the inner plate can be reduced, but in order to secure rigidity of the outer plate, a convex portion is formed on the outer surface side of the outer plate in a shape corresponding to the recess portion, and the pin is lengthened in contrast to this. In this outer plate, a concave portion is formed on the inner surface side, a convex portion is formed on the outer surface side, rigidity is ensured without increasing the weight, and the elastic bending of the pin and the flexibility accompanying the outer plate are suppressed to be small, and even if the pin is longer, the bending moment of the pin becomes larger, and the possibility of bending deformation of the pin and the bending of the outer plate in the expansion direction is also large, as in the conventional seal chain shown in fig. 8.

In addition, since the concave portion is formed in the outer plate, and the seal ring and the sleeve projecting portion are accommodated in the concave portion, a predetermined gap is provided between the sleeve and the pin in order to ensure relative movement between the sleeve and the pin in response to bending of the chain, and thus, relative movement in response to the gap is generated between the seal ring and the sleeve projecting portion accommodated in the concave portion of the outer plate integrated with the pin. As a result, the seal ring may bite between the front end of the sleeve projecting portion and the outer plate, and the seal ring may be worn or broken prematurely.

Disclosure of Invention

In one aspect of the present invention, a seal chain includes: outer links for fixing the pins to both end portions of the pair of outer plates; an inner link in which a bush is press-fitted into bush holes formed in a pair of inner plates, and the pin is inserted into the bush, thereby connecting the inner link and the outer link; and a seal ring that seals lubricating oil interposed between the pin and the sleeve, wherein an inner side surface of the outer plate is formed as a flat surface, the inner plate has a recess on an outer side surface thereof, the recess is concentric with the sleeve hole, and the seal ring is accommodated in the recess and is sandwiched by a predetermined gap existing between the inner side surface of the outer plate and the outer side surface of the inner plate.

Other features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a partially cut-away plan view of a seal chain according to an embodiment of the present invention.

Fig. 2 is a perspective view showing an outer plate thereof.

Fig. 3 is an enlarged partial cross-sectional view of a seal ring having an X-shaped cross-section attached to a recess having an edge portion.

Fig. 4 is an enlarged partial cross-sectional view of a seal ring having an O-shaped cross-section attached to a recess communicating with a sleeve hole.

Fig. 5 is an enlarged cross-sectional view showing an embodiment in which the concave portion of the inner panel communicates with the sleeve hole.

Fig. 6 is an enlarged cross-sectional view showing an embodiment in which the interval between the concave portion of the inner panel and the sleeve hole is defined by the edge portion.

Fig. 7 is a top view in partial cross-section of a seal chain of an embodiment of the present invention in which a tensile force acts.

Fig. 8 is a plan view showing a partial cross section of a conventional seal chain.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in fig. 1, the seal chain 21 has a basic structure of a roller chain in which outer links 25 and inner links 30 are alternately and jointlessly connected, wherein the outer links 25 are configured such that pins 23 are pressed into both end portions of a pair of outer plates 22 to be connected, and both ends of the pins are swaged to be prevented from slipping, and the inner links 30 are configured such that bushings 27 are pressed into both end portions of a pair of inner plates 26 to be fixed, and rollers 29 are loosely fitted into the bushings 27.

The outer side surface 26a of the inner plate 26 is formed as a flat surface, and an annular recess 36 concentric with the sleeve hole 35 is formed in the outer side surface 26 a. The sleeve 27 is press-fitted into and fixed to the sleeve hole 35 so that both ends thereof are substantially coplanar with the outer surface 26a of the inner plate 26. The interval between the concave portion 36 and the sleeve hole 35 is defined by an annular edge portion 37, and the front end surface of the edge portion 37 is coplanar with the outer side surface 26a of the inner plate 26. Therefore, as shown in fig. 2, the concave portion 36 is formed of three surfaces of an outer diameter side surface 36a, an inner diameter side surface 36b, and a bottom surface 36c, and is formed as a groove independent of the sleeve 27 and the sleeve hole 35. As shown in fig. 3, the seal ring 31 is accommodated in the recess 36, and the seal ring 31 is sandwiched between the inner plate 26 and the outer plate 22 with a predetermined compression margin, and the outer side surface 26a of the inner plate 26 and the inner side surface 22a of the outer plate 22 face each other with a relatively narrow gap C.

As shown in fig. 3, the seal ring 31 may be an X-shaped seal ring having an X-shaped cross section, but is not limited thereto, and may be any shape such as an O-shaped seal ring having an O-shaped cross section (see fig. 4). The gap C between the inner plate 26 and the outer plate 22 may be a minute gap for maintaining a predetermined compression allowance of the seal ring 31, but the gap G between the pin 23 and the sleeve 27 is set smaller than the gap C so as to avoid contact between the inner plate and the outer plate. The gap C is 2% to 5% of the diameter of the pin 23, but is also preferable to reduce the bending moment of the pin to maintain the strength of the chain.

In the present seal chain 21, lubricating oil such as grease is injected between the pin 33 and the sleeve 27, and the lubricating oil is sealed with the seal ring 31. In the seal chain 21, the outer links 25 and the inner links 30 bend as the chain advances, and the pin 23 and the bush 27 move relatively when the bending is performed, and the relative movement is smoothly performed by the lubricating oil sealed in the seal ring 31.

The seal chain 21 has a simple structure in which the recess 36 is formed in the outer surface 26a of the inner plate 26, and can reduce the cost. In the seal chain 21, the seal ring 31 is accommodated in the recess 36 formed in the inner plate 26, so that the gap C between the inner plate 26 and the outer plate 22 is a small gap, and the inner side surface 22a of the outer plate 22 is formed as a flat surface, so that the outer plate 22 has a predetermined rigidity while maintaining the plate shape. Therefore, the axial length of the pin 23 is longer than that of a normal roller chain without a seal ring by the minute clearance C, but the amount thereof is extremely small, and it is considered that the axial length is substantially the same as that of a normal roller chain.

Fig. 7 shows a seal chain 21 of the present embodiment in a state in which the same tensile load as that of the conventional seal chain 1 shown in fig. 8 is applied. In the present seal chain 21, since the pin 23 is not long, as shown in fig. 7, the bending moment acting on the pin 23 via the outer plate 22 is small, the bending deformation of the pin 23 is small, and the bending deformation of the outer plate 22 in the expansion direction is also extremely small, and as a result, the seal chain has high resistance to fatigue strength and tensile strength. The outer panel 22 also has less deflection deformation, the seal ring 31 is accommodated in the recess 36, and the compression allowance is also limited by the clearance C, and is moderately compressed, so that deformation is not promoted.

Next, a partially modified embodiment will be described with reference to fig. 4. In the present embodiment, the shape of the recess for accommodating the seal ring 31 is different from that of the previous embodiment, and the other parts are the same, and therefore the same reference numerals are given thereto, and the description thereof is omitted. The present seal chain 21The recess 36' communicates with the sleeve hole 35 until the edge 37 dividing the sleeve hole 35 and the recess 36 in the previous embodiment does not exist. Fig. 4 shows a seal ring 31 (O-ring 31) ₂ ) However, it may be a ring (X-shaped ring 31) having an X-shaped cross section as shown in FIG. 3 ₁ )。

In the present embodiment, the concave portion 36' is formed in the inner plate 26 so as to be concentric with the sleeve hole 35 and communicate with the sleeve hole, so that manufacturing can be facilitated and cost reduction can be further achieved. In particular, for this recess 36', an O-ring 31 ₂ Non-interfering with the sleeve 27, good compatibility, and by using the O-ring 31 ₂ Cost reduction can be further achieved.

According to fig. 5 and 6, the X seal ring 31 is applied ₁ The difference between the recess 36 formed by the separate annular grooves and the recess 36' communicating with the sleeve hole 35 will be described. For the X seal ring 31 ₁ In the natural state, the flange a having a relatively wide width and a nearly circular tip is positioned on the center inner diameter side, and the X-seal ring 31 is provided ₁ Is formed in a cross-sectional shape (refer to Japanese patent application laid-open No. 64-030946 and Japanese patent application laid-open No. 2006-349086 for details). When the cross-shaped ring is interposed between the inner plate 26 and the outer plate 22, the cross-shaped ring rotates around the center flange a, and is attached as an X-shaped seal ring 31 having an X-shaped cross section ₁ 。

As shown in fig. 5, the X seal ring 31 mounted in the recess 36 ₁ A predetermined space e is provided between the center flange a and the sleeve 27, the center flange a is in contact with only the inner side surface 22a of the outer panel 22, the other flange b is in contact with the inner side surface 22a, and the flanges c and d are in contact with the bottom surface 36c of the recess 36'. Therefore, in the X seal ring 31 ₁ The contact 4 is sealed by the total of the predetermined compression margins in the mounted state in which the predetermined gap C is sandwiched between the inner plate 26 and the outer plate 22.

As shown in FIG. 6, the X seal ring 31 is formed ₁ When the X-ring 31 is mounted in the recess 36, the central flange a contacts the front end of the edge 37 to make contact with the front end of the X-ring ₁ Rotated about the central flange aSpecifically, the tip end portion of the edge portion 37 and the 2 of the inner side surface 22a of the outer panel 22 are brought into close contact with the center flange a having a relatively large width, and the gap C for holding the lubricating oil is sealed. The X seal ring 31 ₁ The other flange b of (a) is in contact with the inner side surface 22a, the flange c is in contact with the bottom surface 36c of the recess 36, and the flange d is in contact with the bottom surface 36c of the recess 36 and the corners of the inner diameter side surface 36b on the edge 37 side, respectively. Therefore, the X seal ring 31 is sealed with the prescribed clearance C ₁ In the attached state sandwiched between the inner plate 26 and the outer plate 22, the center flange a is brought into close contact with each other by the seal lubricant, and the contact at 5 points in total is sealed more accurately and reliably.

The seal chain (21) (21') according to the present embodiment is configured such that a pin (23) is inserted into a sleeve (27) and an outer link (25) and an inner link (30) are alternately and jointlessly connected, wherein the outer link (25) is configured such that the pin (23) is fixed to both end portions of a pair of outer plates (22), the inner link (30) is configured such that the sleeve (27) is pressed into sleeve holes (35) formed at both end portions of a pair of inner plates (26), and lubricating oil sandwiched between the pin and the sleeve is sealed by a seal ring (31),

the inner side surface (22 a) of the outer plate (22) is formed as a flat surface,

recesses (36) (36') concentric with the sleeve hole (35) are formed on the outer side surface (26 a) of the inner plate (26),

the seal ring (31) is accommodated in the recess, and the seal ring (31) is held so that a predetermined clearance (C) is provided between the inner side surface (22 a) of the outer panel and the outer side surface (26 a) of the inner panel.

The seal chain may have a simple structure in which a concave portion is formed on an outer side surface of the inner plate, a seal ring is accommodated in the concave portion, cost reduction is achieved, an inner side surface of the outer plate is a flat surface, the seal ring is accommodated in the concave portion, and a gap between the inner plate and the outer plate may be a relatively narrow gap which is almost unchanged from a usual seal-free chain. Thus, the pin does not become long, the bending moment of the pin is prevented from becoming large, and the bending deformation of the pin and the expansion bending deformation of the outer plate are reduced, so that the fatigue strength and the tensile strength of the seal chain can be improved. In addition, the variation in the compression allowance of the seal ring is reduced, and excessive compression deformation of the seal ring can be prevented by the clearance, so that the seal function of the seal ring can be maintained for a long period of time.

For example, referring to fig. 1, 3 and 6, the interval between the inner diameter side of the recess (36) and the sleeve hole (35) is defined by an edge portion (37) having a tip end coplanar with the outer side surface (26 a) of the inner plate (26).

The recessed portion and the sleeve hole are divided by the edge portion, so that accuracy of the recessed portion, particularly accuracy of an inner diameter side surface of the edge portion, is improved, contact accuracy with the seal ring is improved, and abrasion and breakage of the seal ring can be reduced.

Referring to fig. 4 and 5 for example, the recess (36') communicates with the sleeve bore (35).

Since the recess communicates with the sleeve hole, the recess can be easily molded, and productivity can be improved.

For example, the sealing ring (31 ₁ ) The cross section X is formed in a character shape.

The seal ring is an X-shaped ring with an X-shaped cross section, so that the sealing performance is improved, and the friction resistance caused by sealing can be reduced.

For example, the sealing ring (31 ₂ ) The cross section O is formed in a letter shape.

The seal ring is an O-ring having an O-shaped cross section, so that cost reduction can be achieved.

For example, referring to fig. 6, the seal ring (311) is formed in an X-shape in cross section having four flanges (a, b, c, d), one flange (a) of the four flanges is formed to have a wider width than the other flanges (b, c, d) so that the tip end portion of the flange (a) is closer to a circular shape, and the flange (a) is in contact with both the tip end portion of the edge portion (37) and the inner side surface (22 a) of the outer panel (22).

The sealing performance of the seal ring can be improved by forming one flange of the X-shaped seal ring to be wide and having a circular tip portion, and bringing the one flange into contact with the tip portion of the edge portion and the inner side surface 2 of the outer plate

The gap (C) is set to be 2-5% of the diameter of the pin (23) and is set to be wider than the gap (G) between the pin (23) and the sleeve (27).

The gap may be a narrow gap of 2 to 5% of the diameter of the pin, and may be wider than the gap between the pin and the sleeve, so that contact between the inner plate and the outer plate can be prevented.

The above embodiment is not limited to the roller chain, and may be applied to chains other than a roller-less bush chain, for example. In addition, by reducing the deformation of the pin and the outer plate, the diameter of the pin and the miniaturization and weight saving of the seal chain can be realized.

The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the spirit and scope of the present invention. Accordingly, to disclose the scope of the invention, the following claims are appended.

Claims

1. A sealing chain is characterized in that,

the seal chain is provided with:

outer links for fixing the pins to both end portions of the pair of outer plates;

an inner link in which a bush is press-fitted into bush holes formed in a pair of inner plates, and the pin is inserted into the bush, so that the inner link and the outer link are coupled; and

a seal ring for sealing lubricating oil between the pin and the sleeve,

the inner side surface of the outer plate is formed as a flat surface,

the inner plate has a recess on its outer surface concentric with the sleeve hole,

the seal ring is accommodated in the recess and is held so that a predetermined gap exists between an inner side surface of the outer panel and an outer side surface of the inner panel,

the gap defines the compression margin of the seal ring,

the sleeve is press-fitted into the sleeve hole so that both ends thereof are substantially coplanar with the outer side surface of the inner panel.

2. The seal chain of claim 1, wherein,

an inner diameter side of the recess and a space between the sleeve hole are defined by an edge portion where a tip end of the edge portion is coplanar with an outer side surface of the inner panel.

3. The seal chain of claim 1, wherein,

the recess communicates with the sleeve bore.

4. The seal chain of claim 1, wherein,

the seal ring is formed in an X-shaped cross section.

5. The seal chain of claim 1, wherein,

the seal ring is formed in an O-shape in cross section.

6. The seal chain of claim 2, wherein,

the seal ring is formed in an X-shape in cross section having four flanges, one of which has a front end portion closer to a circular shape and a wider width than the other flanges, and which is in contact with both the front end portion of the edge portion and the inner side surface of the outer panel.

7. The seal chain according to any one of claims 1 to 6, wherein,

the clearance is 2% to 5% of the diameter of the pin and is set to be wider than the clearance between the pin and the sleeve.