JPH0989111A - Synthetic resin made seal ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal ring having few dispersion of width dimension in grinding. SOLUTION: In an composite step-cut type synthetic resin made seal ring provided with mating ports 12, 12' fitting each other in the circumferential portion of a ring body 11, one mating port 12' is formed by an outer diameter surface side central projection 14 provided in the outer diameter surface side central portion of the tip surface 16' of the ring body and the other mating port 12 is formed by the outer diameter surface side central recess 15 fitted thereto compensatingly for each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin seal ring for preventing leakage of liquids such as oil and water and fluids such as air and other gases, and mainly relates to automatic speed change gears such as torque converters and hydraulic clutches. The present invention relates to a synthetic resin oil seal ring used for sealing hydraulic oil in a machine.

[0002]

2. Description of the Related Art Conventionally, a metal seal ring or a tetrafluoroethylene resin seal ring has been used as such a seal ring. Recently, injection molding has been performed to improve wear resistance, oil sealability and cost reduction. The use of a synthetic resin seal ring according to US Pat.

These injection-molded synthetic resin seal rings are separated into endless seal rings, or are separated at one location in the circumferential direction for the convenience of mounting, and have a straight cut type as shown in FIG. There are a seal ring provided with the abutments 1 and 1 ', a seal ring provided with a compound step cut type abutments 2 and 2'as shown in FIG.

The seal ring is mounted in a groove provided in the piston, rotates with the relative rotation of the piston and the cylinder, and moves with the relative movement of the two in the axial direction. And slide. Therefore, the seal ring is required to have sufficient sealing property without damaging the sliding surface of the mating member.

In order to facilitate the mold release, the seal ring having the above-mentioned abutments has an expanded state (a state where there is no radial overlap) between the two abutments 2, 2 ', as shown in FIG. ) Is injection-molded in a substantially circular shape or in a state in which it is slightly wider than the circular shape, and when this is mounted on the piston, they are mounted by fitting the mating openings 2 and 2'to each other and then inserted into the cylinder.

Also, the width dimension of the seal ring has a great influence on the seal ring function in relation to the groove dimension of the piston. Both sides of the seal ring are ground after injection molding, and the grinding process is performed by guiding the seal ring to be ground between vertically rotating grinding wheels. In the case of the above endless seal ring, since there is little deformation or warpage of the seal ring, there is little variation in the width dimension, and there are few grinding defects.

[0007]

However, in the case of the seal ring having the above-mentioned abutment, deformation or warpage may occur at the time of injection molding, which causes displacement, biting or escape of the abutment. And so on. As a result, the side surface of the abutment portion is protruded and is ground, so that the width dimension of the seal ring varies. In addition, grinding defects are also likely to occur.

[0008] Therefore, an object of the present invention is to provide a seal ring having less variation in width dimension in grinding.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 is a composite step-cut type composite in which a fitting hole is provided at one location in the circumferential direction of a ring body for fitting with each other. In a resin seal ring, one abutment is formed by the outer diameter side central projection provided at the center part of the outer diameter side of the tip surface of the ring body, and the other abutment is complementarily fitted with this. The structure is formed by the radial surface side central concave portion.

According to a second aspect of the present invention, in the synthetic resin seal ring according to the first aspect, the boundary between the tip surface of the central protrusion on the outer diameter side of the one of the abutments and the outer diameter surface thereof, A chamfer is formed at the boundary between the stepped surface of the central concave portion on the outer diameter surface side of the other abutment and the outer diameter surface of the ring body, and at the boundary between the tip end surface of the ring body and the outer diameter surface of the ring body at each of the aforesaid abutments This is the configuration provided.

According to a third aspect of the present invention, there is provided the synthetic resin seal ring according to the first or second aspect, wherein the tip end surface of the central protrusion of the outer diameter surface of the one of the abutments and the surface on the inner diameter side thereof are provided. And the chamfered portion is provided at each of the boundaries with both side surfaces thereof.

According to a fourth aspect of the present invention, there is provided the synthetic resin seal ring according to the third aspect, in which the inner diameter side surface of the outer diameter surface central projection of the one abutment and both side surfaces thereof and the one side A fillet is provided at the boundary with the tip end surface of the ring body on the mating side, and with the boundary between the stepped surface of the central concave portion on the outer diameter surface side and its inner surface and both side surfaces thereof.

According to a fifth aspect of the present invention, in the synthetic resin seal ring according to any one of the first to fourth aspects, the outer diameter surface central protrusion of the one of the abutments and the other abutment of the other are provided. That is, a constant gap is provided between the surfaces facing the central concave portion of the outer diameter surface.

In the abutment of the present invention, one of the abutments is formed by the outer diameter side central projection provided on the center portion of the ring body front end on the outer diameter side, and the other abutment is complementarily fitted thereto. Since it is formed by the central concave portion on the outer diameter surface side to be fitted, even if deformation or warpage occurs during injection molding, the biting or the like due to it is subdued inside and the side surface of the abutment portion does not project. Therefore, it is possible to reduce the variation in the width dimension of the seal ring due to the grinding process, and it is possible to improve the width dimension accuracy. Further, since the projections and the recesses are provided only on the outer diameter surface side, sufficient sealing performance on the inner diameter surface side can be obtained.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

The first embodiment is shown in FIGS. 1 (a) and 1 (b).
As shown in (c), one abutment 12 'is formed by the outer diameter side central projection 14 provided at the center portion of the ring body tip surface 16' on the outer diameter side, and the other abutment 12 'is A deformed composite step cut type abutment 12, 1 formed by an outer diameter surface side central recess 15 that complementarily fits
It is a seal ring having 2 '.

In one of the mating openings 12 ', a protrusion 14 of a predetermined length is provided at the center of the tip surface 16' of the ring body 11 on the outer diameter surface 21 side. Further, the other abutment 12 is provided with a recess 15 at the center of the other end surface 16 of the ring body 11 on the outer diameter surface 21 side so as to fit with the outer diameter surface side central projection 14. . When one of the abutment holes 12 'and the other abutment hole 12 are fitted to each other, the outer diameter surface central protrusion 14 and the outer diameter surface central recessed portion 15 are inserted, and other than the outer diameter surface central protrusion 14 on the mating opening 12' side. The front end surface 16 'of the ring body and the front end surface 16 of the ring body other than the central recess 15 on the outer diameter surface on the mating port 12 side face each other. The outer diameter surface central protrusion 14
From the ring body tip surface 16 ′ to the tip surface 19 of the outer diameter surface central protrusion 14 and the step surface 18 of the outer diameter surface central recessed portion.
The lengths from the ring body tip surface 16 to the ring body tip surface 16 may be the same, but the ring body tip surface 16 'of the outer diameter surface central projection 14 to the outer diameter surface central projection 1 may be such that the fitting is not weakened.
The length to the tip surface 19 of 4 may be shorter.

By adopting such a shape, the fitting portion of the abutment comes to the center of the ring body, so that even if deformation or warpage occurs during injection molding, biting due to it will occur.
It fits inside and does not cause protrusions or the like on the sides of the abutment. Therefore, even if both side surfaces of the seal ring are ground, the variation in the width dimension can be reduced, and the width dimension accuracy can be improved.

Further, a chamfered portion can be provided at the boundary between the surfaces of the first embodiment. The chamfered portion may have an arc shape (also referred to as "R") having a predetermined curvature, but may have a curvature of 0, that is, a chamfered portion due to an inclined surface (also referred to as "chamfer").
Such a chamfered portion is also called a crowning portion. Such a chamfer can have, for example, a crowning shape in which the curvature continuously changes in various ways. Examples in which such a chamfered portion is provided in the first embodiment will be shown in the second to fifth embodiments.

The second embodiment is shown in FIGS.
As shown in (c), the chamfered portions 31, 32, 3 are formed at the boundaries of the surfaces formed with the outer diameter surface 21 of the first embodiment.
3, 34 are provided. The chamfered portion 31 is a boundary between the side surface side projection of the outer diameter surface side central concave portion of the mating opening 12, that is, the outer diameter surface side surface projection 13 and the ring body tip surface 16 which is the tip of the mating opening 12. Chamfer 32 is a gap 1
It is the boundary between the outer diameter surface 21 of 2'and the tip surface 16 'of the abutment 12'. Further, the chamfered portion 33 is a boundary between the outer diameter surface 21 of the outer diameter side central projection 14 of the mating opening 12 ′ and the tip surface 19 of the central projection 14. Further, the chamfered portion 34 is a boundary between the step surface 18 of the outer diameter surface side central concave portion 15 of the mating opening 12 and the outer diameter surface 21 of the mating opening 12.

By providing these chamfered surfaces 31, 32, 33, and 34, when the seal ring is mounted, even if there is a mismatch in curvature between the seal ring and the mating member on the outer diameter surface side, the abutment 12 It is possible to make the amount of protrusion of the tip portions of the first and second portions 12 'and 12' be zero or small, and it is possible to prevent local contact.

The third embodiment is shown in FIGS. 3 (a) and 3 (b).
As shown in (c), the chamfered portions 36, 37, 38, 39 are formed at the corners of the surfaces that come into contact with each other when the mating openings 12 and 12 'of the first embodiment are fitted together. Is provided. The chamfered portion 36 is a boundary between the inner side surface 23 of the central concave portion on the outer diameter surface side of the mating opening 12 and the ring body tip surface 16 at the tip of the mating opening 12. Chamfer 37 is a gap 1
2 ', the side surface 24 of the outer diameter side central projection 14 and the mating opening 12'
Is the boundary with the tip surface 19 of the outer diameter surface side central protrusion 14.
The chamfered portion 38 is a boundary between the inner surface 17 of the central concave portion 15 on the outer diameter surface side of the mating opening 12 and the ring body tip surface 16 at the tip of the mating opening 12. Further, the chamfered portion 39 and the tip end surface 19 of the central projection 14 on the outer diameter surface side of the fitting opening 12 ′ and the fitting opening 1 are formed.
It is the boundary of the inner diameter side surface 25 of the outer diameter surface side central projection 14 of 2 '.

By providing these chamfers 36, 37, 38, 39, local contact that occurs when fitting the abutments 12, 12 'is avoided or reduced, so that the abutments of each other are prevented. It is possible to prevent damage and the like.

The fourth embodiment is shown in FIGS. 4 (a) and 4 (b).
As shown in (c), the chamfered portion 3 and the chamfered portion 3 shown in the second embodiment are provided at the joints 12 and 12 'of the first embodiment.
1, 32, 33, 34 and the chamfered portions 36, 37, 38, 39 shown in the third embodiment are provided.

This is the chamfered surface 31, 32, 33, 34.
Thus, when the seal ring is mounted, even if there is a mismatch in curvature between the seal ring and the mating member on the outer diameter surface side, the amount of protrusion of the tip end portions of the mating openings 12 and 12 ′ is set to zero or small. In addition to being able to prevent local contact, the chamfered portions 36, 37, 38, 39,
Local contact that occurs when fitting the abutments 12 and 12 ′ can be avoided or reduced, and damage to the abutments and the like can be prevented.

The fifth embodiment is shown in FIGS. 5 (a) and 5 (b).
As shown in (c), the following configuration is added to the fourth embodiment. That is, in this case, at the boundary between the inner diameter side surface 25 of the outer diameter side central projection 14 of the mating port 12 'and the ring body tip surface 16' of the mating port 12 ', the fillet 41, the mating port 1
2 ', the side surface 24 of the outer diameter side central projection 14 and the mating opening 12'
At the boundary of the ring body front end surface 16 ′ of the groove body 42, the step surface 18 of the central concave portion 15 of the outer diameter surface of the joint 12, and the joint 12
At the boundary with the inner side surface 23 of the central concave portion 15 of the outer diameter surface of the
3 and the step surface 1 of the central concave portion 15 of the outer diameter surface of the abutment 12
A fillet 44 is provided at the boundary between the inner surface 17 of the central recess 15 of the outer diameter surface of the contact hole 8 and the inner surface 17. Fillet 41, 4
By providing 2, 43, 44, in addition to the effect of the fourth embodiment, the outer diameter surface side central protrusion 14 and the outer diameter surface central recessed portion 15 are reinforced, and the abutment 1
It is possible to prevent damage or the like due to local contact that occurs when the two 12 'are fitted together.

In the fifth embodiment, fillet is added to the fourth embodiment, but the present invention is not limited to the fourth embodiment, and any of the first to third embodiments. It can be used also in the case, and the same effect of adding the fillet can be obtained as in the fifth embodiment.

The corners other than those corresponding to the above-mentioned corners may be chamfered or have a fillet.

The chamfered portion or the fillet portion may have a curvature or an inclined surface.
A more preferable shape is a chamfered shape having a curvature. The dimension of the chamfered portion or fillet portion near the minimum value is about 5 to 50%, preferably about 5 to 25% of either the axial dimension or the radial dimension of the seal ring.
If this value is too small, it is conceivable that the mating member will be damaged if the amount of protrusion at the abutment portion is slight.

On the other hand, the dimension near the maximum value of the shape of the chamfered portion or fillet portion of the curvature or slope is one of the outer diameter, the inner diameter of the seal ring, or the diameter of the intermediate portion thereof. , About 5 to 50%, preferably about 25 to 50%. If this value is too large, the effect of providing a chamfer is weakened, and only a chamfer that is substantially equivalent to the curvature of the outer diameter of the seal ring can be formed, and the protrusion amount of the abutment portion is set to zero, or We cannot expect to reduce it. In any case, the dimensions of the chamfered portion may be in the range of above these minimum values or above these values, and below these maximum values or below these values.

Further, in the first to fifth embodiments, a predetermined gap may be provided between the facing surfaces of the mating openings 12 and 12 '.
That is, the side surface 24 of the central projection 14 on the outer diameter surface side of the abutment 12 '.
Alternatively, a predetermined gap may be provided between the inner diameter side surface 25 and the inner side surface 23 or the inner surface 17 of the outer diameter surface side central concave portion 15 of the mating port 12. By doing so, local contact at the time of fitting the mating openings 12 and 12 'can be avoided, and the protrusion of the outer diameter side central projection 14 to the outer diameter side of the seal ring can be further reduced. .

Further, in the first to fifth embodiments, the step portion 46 may be provided at the boundary between the outer diameter surface 21 and the side surface 20 and the inner diameter surface 22 and the side surface 20 of the ring body. The size of the step portion 46 is drunk as long as the sealing property of the seal ring is maintained.

(Material of Seal Ring and Molding Method) The seal ring of the present invention can be obtained by molding a resin composition comprising a heat resistant resin, a reinforcing fiber, a fluororesin and a filler.

The heat-resistant resin may be any resin as long as it has heat resistance. For example, a polycyanoaryl ether resin (hereinafter abbreviated as PEN), a polyether-etherketone resin ( Hereinafter, it will be abbreviated as PEEK.) Aromatic polyether ketone resin (hereinafter,
Abbreviated as PEK. ), An aromatic thermoplastic polyimide resin (hereinafter abbreviated as TPI), a polyamide 4-6 resin (hereinafter abbreviated as PA-46), a polyphenylene sulfide resin (hereinafter abbreviated as PPS). Etc. In addition to high heat resistance, these have high flame resistance, excellent mechanical properties, excellent electrical properties, and chemical resistance. These materials are used as the molding base material of the oil seal ring of the present invention. If the melting point of these heat-resistant thermoplastic resins is at least 280 ° C. or higher, they can be preferably used in the present invention.

PEEK such as PEEK used in the present invention
As the above, a ketone polymer having a melting point of 330 ° C. or higher can be used without limitation. PEK is a structural unit represented by the following (Chemical Formula 1) to (Chemical Formula 6), in which an aromatic ring is bonded to include both an ether bond (-O-) and a ketone bond (-CO-). Resins having All of these are crystalline resins. These PEK resins have excellent thermal dimensional properties, and even if they are used as oil seal rings at high temperatures such as heat shrinkage and heat shrinkage of automatic transmissions, there is little dimensional change, and such dimensional accuracy is required. It is suitable for use at a high temperature with a seal ring having a mating shape.

[0036]

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[0038]

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[0040]

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[0042]

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[0044]

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[0046]

[Chemical 6]

(N represents an integer.) Of the above resins, the glass transition point (T
g) is about 165 ° C. and the melting point (Tm) is 365 ° C. As a typical example, UK IC: VICT
REX-PEK 220G (brand name) is mentioned. Further, the glass transition point (Tg) of the resin of (Chemical Formula 2) is about 150.
C., melting point (Tm) is 334 to 337.degree. C., and as a typical example, VICTREX manufactured by UK IC Corp.
-PEEK 150P (brand name) is mentioned. Also,
The glass transition point (Tg) of the resin of (Chemical formula 3) is about 160 ° C.,
The melting point (Tm) is 360 to 380 ° C., and a typical example is HOSTATEC (trade name) manufactured by Hoechst in Germany.
Is mentioned. Further, the resin of (Chemical Formula 4) has a glass transition point (Tg) of about 170 to 175 ° C. and a melting point (Tm) of 375.
The temperature is up to 381 ° C., and a typical example thereof is Ultrapek-A2000 (trade name) manufactured by BASF Germany.

As the heat-resistant resin other than PEEK such as PEEK, well-known resins that are commercially available can be adopted. As a specific example, PEN: Idemitsu Kosan Co., Ltd .: ID300 (trade name), TPI: Mitsui Toatsu Co., Ltd .: Aurum 450 (trade name), PA-46: Japan Synthetic Rubber Co., Ltd .: Stanil TW300 (trade name), P
Kureha Chemical Company as PS: Fortron KPS W21
4 (trade name) and the like can be exemplified.

The blending ratio of the above heat resistant resin is preferably 30 to 82% by weight based on the resin composition of the present invention, and 30
˜78 wt% is more preferred. This is because a small amount of less than 30% by weight results in a decrease in strength, and a large amount of more than 82% by weight is not preferable because the reinforcing effect by the filler cannot be obtained and the abrasion resistance is deteriorated. Because.

The reinforcing fiber in the present invention is not particularly limited, but carbon fiber and aromatic polyamide fiber can be mentioned as examples.

The carbon fiber has an average fiber diameter of 1 to 20 μm.
m, preferably 5 to 18 μm, more preferably 5 to 1
5 μm. Moreover, 1-80 are preferable and, as for an aspect ratio, 5-50 are more preferable. Because, when the average fiber diameter is less than 1 μm, agglomeration between fibers occurs,
This is because it becomes difficult to uniformly disperse the particles, and a thick material having a thickness of more than 20 μm causes abrasion of the soft counterpart material. When the average fiber diameter is in the above range, such a tendency is lessened, which is preferable. On the other hand, if the aspect ratio is less than 1, the reinforcing effect of the matrix itself is impaired and the mechanical properties are deteriorated. On the other hand, if it exceeds 80, uniform dispersion during mixing is extremely difficult and wear characteristics are hindered. This is because it is not preferable because it causes a decrease. When the aspect ratio is 1 to 80, such a tendency is relatively small, and favorable results are obtained.

The aromatic polyamide fiber is well known as a fibrous heat-resistant resin represented by the following formula (Chemical formula 7), and aromatic rings bonded with an amide bond at the meta position, an aromatic ring It may be any of those in which the group ring is linked by an amide bond at the para position.

[0053]

[Chemical 7]

Among them, the para-aromatic polyamide fiber is a para-aromatic polyamide fiber containing a repeating unit represented by the following formula (Formula 8).

[0055]

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Since the para-aromatic polyamide fiber has molecular chains arranged in the axial direction of the fiber, it has high elasticity in the axial direction.
It has high strength, but weak intermolecular force in the perpendicular direction. As described above, the para-aromatic polyamide fiber can improve the abrasion resistance of the blended resin composition well due to the strength in the axial direction. On the other hand, when the compressive force is applied in the direction perpendicular to the fiber, the molecular chain buckles. Or, since it is easily broken, it is considered that it does not damage the soft sliding mating material.

When an aromatic polyamide fiber other than a para-based resin is used, by adding a resin containing a predetermined amount of a fluorine-based resin such as a tetrafluoroethylene resin, the same soft sliding property as that of the above composition can be obtained. It is possible to obtain a composition having excellent wear resistance without damaging the moving partner material.

Such aromatic polyamide fiber preferably has a fiber length of about 0.15 to 3 mm and an aspect ratio of about 1 to 230. The average fiber diameter is about 1 to 20μ.
It is preferably m, and more preferably about 5 to 15 μm. The aspect ratio is preferably about 1 to 60, more preferably about 15 to 40. If the fiber length of the aromatic polyamide fiber is less than the predetermined range, the abrasion resistance becomes insufficient, and if the fiber length exceeds the above range, the dispersion in the composition is unsatisfactory, which is not preferable. On the other hand, if the aspect ratio is less than 1, the shape is close to that of powder, the effect of improving the wear resistance is insufficient, the reinforcing effect of the matrix is lost, and the mechanical properties are lowered. On the other hand, when it exceeds 60, it becomes difficult to uniformly disperse it during mixing, and the wear characteristics of the composition are not uniform.

When the average fiber diameter is less than about 1 μm, the fibers are aggregated when mixed into the matrix, and uniform dispersion is difficult, and the average fiber diameter is about 20 μm.
If the diameter is larger than m, the composition may slide and wear the soft counterpart material. Those having an average fiber diameter of about 5 to 15 μm are extremely preferable because such a tendency is not observed at all.

The proportion of the reinforcing fiber in the total resin composition is 5 to 45% by weight, preferably 10 to 45% by weight, more preferably 10 to 30% by weight. Because 5
If it is less than 5% by weight, the wear resistance of the molded body is hardly improved and
This is because if the amount is more than 10% by weight, the melt fluidity is significantly reduced and the moldability is deteriorated. When the blending ratio is 10 to 30% by weight, such a tendency does not occur at all, and a preferable result is obtained.

The fluororesin used in this invention is
For example, polytetrafluoroethylene (hereinafter abbreviated as PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (abbreviated as PFA),
Tetrafluoroethylene-hexafluoropropylene copolymer (abbreviated as FEP), ethylene-tetrafluoroethylene copolymer (abbreviated as ETFE), tetrafluoroethylene-fluoroalkyl vinyl ether-fluoroolefin copolymer (abbreviated as EPE) ), Polychlorotrifluoroethylene (abbreviated as PCTFE), ethylene-chlorotrifluoroethylene copolymer (abbreviated as ECTFE), polyvinylidene fluoride (P).
Examples thereof include VDF) and polyvinyl fluoride (abbreviated as PVF). These may be used alone or in the range of 1:10 to 10: 1, for example, fluorinated polyolefins such as the above-mentioned two or more copolymers and terpolymers, and the like. The characteristics as an agent are shown.

Of these, PTFE has a melting point of about 327 ° C. and a melt viscosity of about 10 ¹¹ -1 even at about 340-380 ° C.
It is considered to be a resin having the highest heat resistance among fluororesins because it has a high value of 0 ¹² poise and is hard to flow even if it exceeds the melting point. When such PTFE is adopted, it may be a powder for molding or a so-called fine powder for a solid lubricant, and a commercially available product is Teflon 7J manufactured by Mitsui DuPont Fluorochemicals. (Product name), T
LP-10 (trade name), Asahi Glass Co., Ltd .: FLUON G163
(Trade name), manufactured by Daikin Industries, Ltd .: polyflon M15 (trade name), Lubron L5 (trade name), and the like. Alternatively, PTFE modified with an alkyl vinyl ether may be used. Generally, PTFE is a homopolymer of tetrafluoroethylene, and a commercially available resin can be used as a compression-moldable resin, for example, manufactured by Kitamura:
400H (trade name) or the like can be adopted.

As the PFA, Teflon PFA-J (trade name) and MP-1 manufactured by Mitsui DuPont Fluorochemical Co., Ltd.
0 (commercial name), Hoechst: Hostafuron TFA (commercial name), Daikin Industries, Ltd .: Neoflon PFA (commercial name), FEP as Mitsui DuPont Fluorochemicals Co., Ltd .: Teflon FEP-J (commercial name), Daikin Industries, Ltd .: Neoflon FEP (trade name), ETFE: Mitsui DuPont Fluorochemicals: Tefzel (trade name), Asahi Glass Co .: Aflon COP (trade name), and EPE: Mitsui DuPont Fluorochemical Co .: Teflon EPE-J (trade name) and the like can be mentioned.

Perfluorinated fluororesins such as PTFE, PFA and FEP are in a state in which the carbon base paper as the skeleton is entirely surrounded by the fluorine base paper or a trace amount of oxygen atoms, and a strong bond between C and F is generated. Among the fluorine-based resins, the heat resistance temperature is relatively high, and various characteristics such as low friction coefficient, non-adhesiveness, and chemical resistance are excellent, which are preferable. PVD
Examples of F include KF polymer (trade name) manufactured by Kureha Chemical Industry Co., Ltd.

The mixing ratio of the above-mentioned fluororesin is 2 to 25% by weight, preferably 5 to 25% by weight. This is because if it is less than 2% by weight, the sliding characteristics such as self-lubricating property and abrasion resistance are not significantly improved, and if it exceeds 25% by weight, the formability is deteriorated and the mechanical properties are deteriorated. . When the blending ratio is 5 to 25% by weight, such a tendency is hardly seen and a preferable result is obtained.

The filler used in the present invention is, for example,
Examples thereof include powder talc and calcium-based powder filler.

The powdered talc has an average particle size of about 0.5 to
40 μm is preferable, and about 1 to 30 μm is more preferable.
This is because small particles of less than about 0.5 μm cause agglomeration between particles to make uniform dispersion difficult, and large particles of more than about 40 μm result in poor surface smoothness, which is not preferable.

Examples of the calcium-based powder filler include calcium carbonate, sulfate, oxide, and hydroxide, of which calcium carbonate or calcium sulfate is preferable. The average particle size of the calcium-based filler is about 0.
5-40 micrometers is preferred and about 1-30 micrometers is more preferred. This is because small particles of less than about 0.5 μm cause agglomeration between particles to make uniform dispersion difficult, and large particles of more than about 40 μm result in poor surface smoothness, which is not preferable.

The blending ratio of the above-mentioned filler is preferably 10 to 40% by weight, more preferably 10 to 30% by weight, based on the total resin composition. This is because if it is less than 10% by weight, the soft counterpart material is abraded, and if it exceeds 40% by weight, the formability is deteriorated and the mechanical properties are deteriorated. The same mixture ratio is 10-30
If it is% by weight, there is no such tendency, and preferable results are obtained.

In addition to the above, molybdenum disulfide or the like can be used as the antiwear agent. This molybdenum disulfide is added in order to improve wear resistance, and its mixing ratio is preferably 1 to 10% by weight. Because, in the compounding amount less than the above predetermined range, the improvement of sliding characteristics such as self-lubricating property and abrasion resistance is not significantly recognized, and in the compounding amount exceeding the above predetermined range, the mechanical strength decreases, and This is because the wear resistance is not improved in proportion to the blended amount.

The following are examples of combinations in the resin composition used for the seal ring of the present invention.

TPI, PEEK, PEK, PEN,
A resin composition containing 30 to 82% by weight of any one resin selected from the group consisting of PA-46 and PPS, 5 to 45% by weight of carbon fiber, and 2 to 25% by weight of a fluororesin.

PEN, PEEK, PEK, TPI,
30 to 82% by weight of any one resin selected from the group consisting of PPS and PA-46, 5 to 45% by weight of carbon fiber,
Fluorine resin 2-25% by weight, powdered talc 10-40
A resin composition whose main component is wt%.

PEN, PEEK, PEK, TPI,
Mainly contains 30 to 78% by weight of any one resin selected from the group consisting of PPS and PA-46, 10 to 45% by weight of carbon fiber, 2 to 25% by weight of fluororesin, and 10 to 40% by weight of powdered calcium compound. A resin composition as a component.

PEN, PEEK, PEK, TPI,
30 to 82% by weight of any one resin selected from the group consisting of PPS and PA-46, 5 to 45% by weight of carbon fiber,
Fluorine resin 2-25% by weight, powdered talc 10-40
A resin composition comprising 1 wt% and 1-10 wt% molybdenum disulfide.

10 to 40% by weight of the powdered talc
A mixture containing 10 to 40% by weight of a calcium powder filler in place of the above.

A blend of 5 to 45% by weight of aromatic polyamide fiber instead of 5 to 45% by weight of carbon fiber.

Aromatic polyamide fibers of 5 to 45% by weight are blended in place of the carbon fibers of 5 to 45% by weight, and calcium talc filler of 10 to 40% by weight is substituted for powdered talc of 10 to 40% by weight. A resin composition containing

The resin composition of the present invention has the purpose of improving the self-lubricating property, the mechanical strength, the thermal stability, and the like, and coloring, as long as the additives other than the above do not impair the effects of the present invention. Then, solid lubricants, fillers, powder fillers, pigments, and other substances that are stable at a high temperature of about 350 ° C. or higher may be appropriately mixed. For example, in order to further improve the lubricity of the resin composition, a wear resistance improver can be added. Specific examples of this wear resistance improver include carbon, graphite, mica, wollastonite, powders of metal oxides, whiskers such as calcium sulfate, phosphates, carbonates, stearates, and ultra-high molecular weight polyethylene. Can be illustrated. The balance of the heat resistant resin when adding such an additive is preferably not less than about 40% by weight.

The method for adding and mixing various additives to these heat resistant resins is not particularly limited, and a method that is generally widely used, for example, a resin as a main component,
Other various raw materials are individually or individually dry-mixed by a mixer such as a Henschel mixer, a ball mill, a tumbler mixer, and then supplied to an injection molding machine or a melt extrusion molding machine having a good melt-mixing property, or a hot roll in advance. , Kneader, Banbury mixer, melt extruder, and the like may be used.

Further, when molding the above composition,
The molding method is not particularly limited, and a usual method such as compression molding, extrusion molding, injection molding, or after melt-mixing the composition, the composition is pulverized by a jet mill, a freeze pulverizer, or the like to obtain a desired particle size. It is also possible to classify into. Among them, the injection molding method has excellent productivity and can provide an inexpensive molded body.

The particles such as pellets thus obtained may be subjected to the same drying treatment as the below-mentioned heat treatment before molding. It is considered that by sufficiently evaporating water and the like from the particles such as pellets, it is possible to prevent swelling and reduction in strength of the molded body.

The molded product thus obtained is heated at about 100 to 280 ° C. for about 0.1 to 24 hours in order to secure dimensional stability at high temperature except heat setting and strain at the time of molding. It is desirable to perform the annealing heat treatment of.

The annealing heat treatment temperature depends on the material,
Approximately 280 ° C or lower, for example, approximately 140 to 270 ° C, and approximately 140 to 230 ° C or approximately 140 to 200 depending on the material.
It is suitable to carry out at about ° C. These heat-resistant resins have high rigidity over a wide temperature range, excellent impact resistance, are strong against distortion such as creep, and are resistant to almost all types of oils and chemicals. . Further, these resins are crystalline and have properties such as an increase in strength and rigidity due to an increase in crystallinity, an improvement in wear resistance and lubricity, and a decrease in thermal expansion coefficient and water absorption.

When the heat treatment temperature is lower than about 140 ° C.,
It is considered that it takes a lot of time for the crystallization to proceed, the efficiency is low, it is difficult to remove a slight strain of the molded body, and it is difficult to obtain the dimensional stability.

When the annealing heat treatment temperature exceeds the heat deformation temperature by about 20 to 30 ° C., the influence of the heat history applied to the resin is considered to be unfavorable, which is not preferable. During the heat treatment, before reaching the predetermined temperature, for example, at room temperature, about 80 ° C., about 130 ° C., about 180 ° C., about 220 ° C., about 230 ° C., about 280 ° C. The temperature may be gradually raised every about 15 to 60 minutes in the range of about 15 to 180 minutes, and the temperature may be kept constant at the optimum temperature within the temperature range within the time range. The maximum temperature holding time in that case is about 15
It may be about 480 minutes. If the holding time at the maximum temperature is shorter than the specified time, the crystallization of the resin will be insufficient and the dimensional stability will be poor, and if it is longer than the specified time, "warping" will be inappropriate. It is difficult to reduce the manufacturing cost in view of an increase in the energy consumption of an electric furnace and an increase in the manufacturing time.

Further, when the temperature is raised to about 90 to 120 ° C., it may be held at such a constant temperature. By doing so, it is possible to dry the water taken in a little in the molded body and then crystallize it. On the other hand, it is not preferable to end the heat treatment by rapidly heating in a short time. This is because the water content above the boiling point is vaporized, and the volume expansion at that time increases the possibility that defects such as “swelling” occur in the molded body.

The cooling after the crystallization step may be carried out through the steps opposite to the above temperature rising, or may be continuously gradually cooled over a time period of about 60 to 180 minutes.

By carrying out the heat treatment process as described above, the occurrence of defects such as swelling of the molded body is prevented as much as possible, and the crystallization of the resin is surely and gradually advanced to improve the dimensional stability of the molded body. It is possible to provide a molded product with high dimensional accuracy.

The surface roughness of the sliding surface of at least one of the molded body and the mating member is JI such as Rmax, Ra or Rz.
According to the evaluation method defined by S, it is about 3 to 25 μm or less, preferably about 8 μm or less, more preferably about 3 μm.
m or less. This is because, if the surface roughness exceeds the above-mentioned predetermined range, the sliding surface is likely to have many scratches, which is considered to cause wear.

Since it takes a long time to finish the surface of the mating material, it may be inefficient or affected by the formation of the transition film of the resin material. It is presumed that the range may be about 3 to 8 μm or less under the above conditions.

The mating material for the piston, cylinder, etc. is carbon steel such as S45C, SCM420H, FCD45, etc.
It may be a hard material such as spheroidal graphite cast iron or the like, or a hardened material thereof, or a soft material such as an aluminum alloy such as ADC12.

[0093]

According to the seal ring of the present invention, one abutment is formed by the outer diameter side central projection, and the other abutment is formed by the outer diameter side central concave portion which complementarily fits with this. Therefore, even if deformation or warpage occurs during injection molding, the side surface of the abutment part does not project, and the variation in the width dimension of the seal ring due to the grinding process can be reduced, and the width dimension accuracy is improved. be able to.

Further, in the seal ring according to the invention of claim 2 or 3, due to the presence of the chamfered portion, the contact between the abutting portion to be fitted with the abutting portion and the local contact between the abutting portion and the mating member are caused. Since this can be prevented, damage to the abutment, wear of the mating member, etc. can be reduced.

Further, in the seal ring according to the fourth aspect of the present invention, since the fillet is provided at the abutment portion, it is possible to prevent damage due to contact when the abutment is fitted.

Furthermore, in the seal ring according to the invention of claim 5, a gap is provided on the surfaces facing each other when the abutment is fitted, so that the abutment part and the abutment part to be fitted are brought into contact with each other. Since it is possible to prevent local contact between the mouth portion and the mating member, it is possible to reduce damage to the abutment, wear of the mating member, and the like.

[Brief description of drawings]

1A is a partial front view of the first embodiment, FIG. 1B is a partial plan view of the same, and FIG. 1C is a partial perspective view of the same.

2A is a partial front view of the second embodiment, FIG. 2B is a partial plan view of the same, and FIG. 2C is a partial perspective view of the same.

3A is a partial front view of the third embodiment, FIG. 3B is a partial plan view of the same, and FIG. 3C is a partial perspective view of the same.

4A is a partial front view of the fourth embodiment, FIG. 4B is a partial plan view of the same, and FIG. 4C is a partial perspective view of the same.

5A is a partial front view of the fifth embodiment, FIG. 5B is a partial plan view of the same, and FIG. 5C is a partial perspective view of the same.

FIG. 6 is a partial perspective view of a sixth embodiment.

FIG. 7A is a partial front view of a conventional example. FIG. 7B is a partial plan view of the same.

FIG. 8A is a partial front view of another conventional example. FIG. 8B is a partial plan view of the same.

9 (a) is a partial front view after molding of the conventional example of FIG. 8 (b) is a partial plan view of the same.

[Explanation of symbols]

 1, 1'Abutment 2, 2'Abutment 3 Protrusion 4 Stepped portion 11 Ring body 12, 12 'Abutment 13 Outer diameter side side protrusion 14 Outer diameter side central protrusion 15 Outer diameter side central recess 16, 16 'Ring body tip surface 17 Recess inner surface 18 Step surface 19 Center protrusion tip surface 20 Ring body side surface 21 Outer diameter surface 22 Inner diameter surface 23 Recess inner surface 24 Center protrusion side surface 25 Center protrusion inner diameter side surface 31 Chamfering portion 32 Chamfering portion 33 Chamfering portion 34 Chamfer 36 Chamfer 37 Chamfer 38 Chamfer 39 Chamfer 41 Fillet 42 Fillet 43 Fillet 44 Fillet 46 Ring body step

Claims (5)

[Claims] 1. A composite step-cut type synthetic resin seal ring having a fitting hole for fitting with each other at one position in the circumferential direction of the ring body. A synthetic resin seal ring, characterized in that it is formed by an outer diameter surface side central protrusion provided in a side center portion, and the other abutment is formed by an outer diameter surface side central concave portion that complementarily fits with this. 2. A boundary between a tip end surface of the central protrusion on the outer diameter surface side of the one mating opening and the outer diameter surface thereof, a step surface of the central concave portion on the outer diameter surface side of the other mating opening, and the outside of the ring body. The synthetic resin seal ring according to claim 1, wherein a chamfered portion is provided at each of the boundary with the radial surface and the boundary between the tip end surface of the ring body and the outer diameter surface of the ring body at each of the mating ports. 3. A chamfered portion is provided at each of the boundaries between the tip end surface of the outer diameter surface central protrusion of the one abutment and the inner diameter side surface and both side surfaces thereof. 2. The synthetic resin seal ring according to any one of 2 above. 4. A boundary between an inner diameter side surface of the outer diameter surface central projection and the both side surfaces of the one abutment opening and a ring body tip surface on the one abutment opening side, and the outer diameter surface side. The synthetic resin seal ring according to claim 3, wherein fillets are provided at boundaries of the step surface of the central recess and the inner surface and both side surfaces thereof. 5. A constant gap is provided between the surfaces of the outer diameter surface central protrusion of the one abutment and the outer diameter surface central recess of the other abutment facing each other. The synthetic resin seal ring according to any one of claims 1 to 4.