JPH0996363A - Seal ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove a burr in the forming time easily, in a seal ring made of a synthetic resin, by composing to make the angle made by a seal face and the surfaces of lubricating grooves at the border of both members in an obtuse angle. SOLUTION: In a seal ring 21 having an abutment 23, lubricating grooves 22 are formed to make the angle θ made by a seal face 24 and the surfaces of the lubricating grooves 22 at the border of the seal face 24 and the lubricating grooves 22 an obtuse angle, that is, more than 90 deg. and less than 180 deg., preferably 120 deg. to 135 deg.. And the depth of the lubricating grooves is made about 0.2mm, the width at the bottoms of the lubricating grooves is made a minute value about 0.35mm, and even though the lubricating grooves are provided at about three positions, the sealing property is not hurt. And by regulating the angle θ, a desired area of the opening ends of the lubricating grooves 22 can be obtained, and a produced burr can be removed easily by a barrel processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal ring, and more particularly to an oil seal ring made of a synthetic resin which is mainly used for sealing hydraulic oil for automobile automatic transmissions.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 8, a seal ring 1 is mounted in a circumferential groove 3 of a shaft 2, and an outer peripheral sealing surface 10 of the seal ring 1 is pressed against an inner peripheral surface of a cylinder 4 for sealing. , One of the sealing surfaces on both sides 5
Is pressed against the inner wall of the circumferential groove 3 to seal the circumferential groove 3.

In the case of a device in which the shaft 2 rotates, the sealing surface 5
Since sliding frictional resistance and wear occur between the inner wall of the peripheral groove 3 and the peripheral groove 3, it is proposed to use the seal ring 1 as shown in FIGS. It is also considered to use the seal ring 1 as shown in FIG.

These seal rings 1 have lubricating grooves 7, 8, 9 formed in the sealing surface 5, and by introducing a lubricant into the lubricating grooves 7, 8, 9 a lubricating film is formed on the sealing surface 5. Are formed.

[0005]

However, in order to prevent the sealing properties of the sealing surface 5 from being impaired by the above-mentioned lubricating grooves 7 and 8, the inner peripheral side of the sealing surface 5 is open.
The outer peripheral side is closed. Therefore, the outer peripheral portion of the seal surface 5 is in close contact with the inner wall of the peripheral groove 3 over the entire peripheral surface thereof, so that no lubricating film is formed. As a result, if the shaft 2 is made of a soft material such as aluminum alloy, the relative rotation between the seal ring 1 and the shaft 2 causes wear on the seal surface 5, or if the shaft 2 is made of a material having low wear resistance such as aluminum. In some cases, the inner wall of the circumferential groove 3 may be worn.

Therefore, in order to improve the wear resistance of the seal ring itself or a mating member while maintaining the sealability of the seal ring and forming a lubricating film on the entire seal surface, as shown in FIG. It is considered to form the lubrication groove 8 penetrating from the outer peripheral sealing surface 10 to the inner peripheral sealing surface. The lubricating groove 8 is a groove that can maintain the sealing property, and its shape is such that the angle θ ′ between the sealing surface 5 and the side wall of the lubricating groove 8 is a right angle as shown in FIG. 12C. There is.

The cross-sectional shape of the seal ring 1 shown in FIGS. 10 and 11 is rectangular as a whole, and when the seal ring 1 is molded from synthetic resin, as shown in FIG. The mating surface 12 is the seal ring 1.
It is set at a corner portion (that is, one end of the outer peripheral seal surface 10) between the one seal surface 5 and the outer peripheral seal surface 10. With this setting, the burr 13 at the time of molding is formed at a position deviating from both the seal surface 5 and the outer peripheral seal surface 10, and the generated position is the corner portion.
The burr 12 is easily removed.

However, in order to improve the wear resistance of the seal ring itself or the mating member, the lubricating groove 9 shown in FIG. 12 is used.
In the case where the above is formed, when this is injection-molded with the mold 11 as shown in FIG. 13, the burr 12 closes the lubricating groove 8. To remove this burr, remove it by barreling,
If the barrel particles used for barreling are larger than the groove width, the burr will fall into the groove and cannot be removed.
Also, when the barrel particles are made smaller than the groove width, the barrel particles enter the groove and cannot be removed. In such a case, it is necessary to manually remove burrs and barrel particles using the tip of a cutter or the like.

Therefore, an object of the present invention is to provide a synthetic resin seal ring which can easily remove burrs during molding and can form a lubricating film on the entire sealing surface. Is.

[0010]

In order to solve the above problems, in the present invention, sealing surfaces are formed on both side surfaces of the ring, and lubricating grooves are provided on the sealing surfaces from the inner circumference to the outer circumference in a penetrating manner. In the seal ring, the angle between the sealing surface and the surface of the lubricating groove at the boundary between the sealing surface and the lubricating groove is an obtuse angle.

According to the above structure, the lubricant leaks from the lubricating groove, so that the relative rotation with the mating member forms a lubricating film over the entire width of the sealing surface. Function is maintained.

Further, at the boundary between the sealing surface and the lubricating groove, the angle between the sealing surface and the surface of the lubricating groove is an obtuse angle, so that the original function of the seal ring is maintained and the sealing surface of the sealing surface is maintained. Since the area occupied by the lubricating groove, that is, the area of the opening end of the lubricating groove can be increased, the burrs can be easily removed only by the tumbler treatment. Further, since the angle formed by the sealing surface and the surface of the lubricating groove is an obtuse angle, even when particles smaller than the groove are used, the particles can be easily removed from the groove and the particles remain in the groove. Is eliminated and manual post-treatment is unnecessary.

[0013]

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 a seal ring 21 having a mating port 23 as shown in FIG. 1, and an inner peripheral seal is formed on a seal surface 24 on one side surface of the seal ring 21 at approximately three equal positions. A lubricating groove 22 penetrating from the surface to the outer peripheral sealing surface 25 is formed, and a similar lubricating groove 22 is also formed on the other side of the sealing surface 24 with a slight displacement.

In these lubricating grooves 22, the angle θ formed between the sealing surface 24 and the surface of the lubricating groove 22 at the boundary between the sealing surface 24 and the lubricating groove 22 is an obtuse angle, that is, 90 ° or more and 180 degrees.
It is less than 90 °, preferably 120 ° to 135 °. Further, the depth of these lubricating grooves is about 0.2 mm, and the width thereof is as fine as about 0.35 mm at the bottom of the lubricating groove.
Even if it is provided in three places as described above, the sealing property is not impaired. Further, by adjusting the angle θ, any lubrication groove 22
The area of the open end can be obtained, and even if the mold shown in FIG. 12 is used, the generated burr can be easily removed by the barrel treatment.

The abutment 23 is not limited to the step-cut type shown in FIG. 1A, but may be a straight-cut type, a composite step-cut type, an endless type, or the like depending on the purpose of use. Can be used. Furthermore, crowning may be performed on the boundary between the open end of the lubricating groove 22 and the seal surface 24, the boundary between the seal surface 24 and the outer peripheral seal surface 25 or the inner peripheral seal surface, and the boundary between the surfaces at the abutment portion.

A step portion may be formed at the boundary between the seal surface 24 and the outer peripheral seal surface 25 or the inner peripheral seal surface of the first embodiment. The second embodiment shown in FIG. 2 is one in which this step portion is formed. In this case, the step portion 26 is provided because of the sealing surface 24, the outer peripheral sealing surface 25, and the inner peripheral sealing surface 3.
Since it is the boundary with 6, the lubricating groove 22 can be formed in the same manner as in the first embodiment.

In these lubricating grooves 22, the angle θ formed between the sealing surface 24 and the surface of the lubricating groove 22 at the boundary between the sealing surface 24 and the lubricating groove 22 is an obtuse angle, that is, 90 ° or more, and 180
It is less than 90 °, preferably 120 ° to 135 °. Further, the depth of these lubrication grooves is about 0.2 mm, and the width thereof is as fine as about 0.35 mm at the bottom of the lubrication groove.
Even if it is provided in three places as described above, the sealing property is not impaired. Further, by adjusting the angle θ, any lubrication groove 22
The area of the open end can be obtained.

As shown in FIGS. 2D and 2E, the step portion 26 has a sectional shape of the seal ring 21 between the seal surfaces 24 on both sides and the outer peripheral seal surface 25 and on both sides.
4 and the inner peripheral sealing surface, respectively. As shown in FIG. 2 (f), the step portion 26 has a right-angled surface 27 with respect to the seal surface 24, a right-angled surface 27 ′ with respect to the outer peripheral seal surface 25, and an inclined surface 28 formed between these right-angled surfaces 27, 27 ′. The height h of the stepped portion 26 is higher than the depth of the lubricating groove 22.

The height h of the step portion 26 is not particularly limited, but the length of the rectangular cross section of the seal ring 21 in the radial direction,
Alternatively, each of the axial lengths is about 5 to 50%, preferably about 5 to 25%, more preferably about 5 to 10%, and it is preferable to provide the seal ring 21 on one side or both sides. For any of the above numerical ranges, below the lower limit,
You may select in the range less than an upper limit.

If the height h of the step is too small, there is a possibility of causing a defect when the displacement between the movable die and the fixed die during long-term use of the die occurs in a relatively short cycle. If too much, the area of the seal portion of the seal ring, that is, the so-called seal land is reduced, so that reliable and good sealing characteristics cannot be expected.

The abutment 23 is not limited to the step cut type shown in FIG. 2 (a), but may be a straight cut type, a composite step cut type, an endless type, or the like depending on the purpose of use. Can be used. Furthermore, crowning may be performed on the boundary between the open end of the lubricating groove 22 and the seal surface 24, the boundary between the seal surface 24 and the outer peripheral seal surface 25 or the inner peripheral seal surface, and the boundary between the surfaces at the abutment portion.

FIG. 3 shows the position of the mating surface 31 of the mold 29 when the seal ring 21 in the second embodiment is injection molded with synthetic resin. That is, the mating surface 31
Is set at one end of the outer peripheral seal surface 25 on the side of the step 26. When the mating surface 31 is set at such a position, the burr 32 is formed at a position apart from the lubricating groove 22, so that the lubricating groove is not closed and the burr 32 need not be removed.

In the third embodiment, as shown in FIGS. 4 (a) and 4 (b), the lubricating groove 22 of the seal ring 21 is a circumferential groove 33 formed in the central portion of the seal surface 24 over the entire circumference.
And an outer diameter groove 34 and an inner diameter groove 35 which are formed from the circumferential groove 33 in the outer circumferential direction and the inner circumferential direction, respectively, and the positions of the outer radial groove 34 and the inner diameter groove 35 are displaced in the circumferential direction. There is.

The lubricating groove 22 of the seal ring of the fourth embodiment shown in FIGS. 5A and 5B comprises an outer radial groove 34 and an inward groove 35 formed at the same position as the circumferential groove 33.

Next, the cross-sectional shape of the lubricating groove 22 is shown in FIG.
(B) Not limited to the trapezoid as shown in FIG. 2 (b), when the angle between the sealing surface and the surface of the lubrication groove at the boundary between the sealing surface and the lubrication groove is an obtuse angle, at the time of molding It becomes easy to remove the burr. An example of the shape is a shape as shown in FIG. FIG. 6A is a trapezoid as shown in FIGS. 1B and 2B. FIG. 5B shows a V shape. 5C, 5D, and 5E are circular or elliptical, and the angle θ is an obtuse angle. Figure 5 (f)
In (g) and (h), a chamfered portion is formed between the seal surface 24 and the lubricating groove, and the angle θ is an obtuse angle. The preferable range of the angle θ is the same as that in the case of the first embodiment. It is preferable that the groove width B and the depth H are dimensions that can be formed by injection molding, and the groove width B is the axial dimension of the seal ring because of the requirement for the retention of the lubricant and the contact with the seal ring 21. Or, it is estimated that the range of about 0.001 to 0.1 times the radial dimension is preferable, and the range of about 0.01 to 0.05 times is most preferable. Good. Further, it is estimated that the depth H is most preferably in the same range as the groove width B.

If the groove width and the groove depth are too large, the contact surface pressure at the sliding portion between the seal ring and the seal surface of the mating member groove portion becomes high, which is likely to cause abrasion and strength reduction. If it is too small, it becomes difficult to obtain the lubricating effect of the lubricant.

FIGS. 7A to 7D show a modified example of the lubricating groove 22. FIG. 7A shows two lubricating grooves 22.
Are not parallel, but the outer peripheral sealing surface 25 and the inner peripheral sealing surface 36
In, the widths of the two lubricating grooves 22 are different. Figure 7 (b)
Although the two lubrication grooves 22 are parallel to each other, the grooves are not cut perpendicularly to the outer peripheral sealing surface 25 and are inclined at a predetermined angle. FIG. 7C shows two lubricating grooves 2
Two are crossed with each other. In FIG. 7D, a plurality of thin lubricating grooves 22 are densely arranged within a predetermined width.
In a pair of groove shapes intersecting with each other as shown in FIG.
It is estimated that it is possible to evenly and uniformly supply the lubricant to the sliding surface between the seal ring and the sealing surface of the mating material groove with a small number of grooves, and because the number of grooves is small, the contact surface pressure on the sliding surface can be reduced. It is also possible to reduce it.

(Material for Seal Ring and Molding Method) The seal ring of the present invention is 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.

[0032]

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(N represents an integer.)

[0034]

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[0036]

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[0038]

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[0040]

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[0042]

[Chemical 6]

(N represents an integer.) Among the above resins, the glass transition point (Tg) of the resin of Chemical formula 1 is about 165.
C., melting point (Tm) is 365.degree. C., and as a typical example, VICTREX-PE manufactured by UK IC Corp.
K 220G (trade name) is included. Also, (Chemical formula 2)
The glass transition point (Tg) of the resin is about 150 ° C and the melting point (Tg)
m) is 334 to 337 ° C., and as a typical example, VICTREX-PEEK manufactured by British IC KK
150P (brand name) is mentioned. Further, the glass transition point (Tg) of the resin of (Chemical Formula 3) is about 160 ° C. and the melting point (Tm)
Is 360 to 380 ° C., and a typical example thereof is HOSTATEC (trade name) manufactured by Hoechst in Germany. Furthermore, the glass transition point (Tg) of the resin of (Chemical formula 4) is about 170 to 175 ° C, and the melting point (Tm) is 375 to 381 ° C.
And a typical example thereof is Ultrapek-A2000 (trade name) manufactured by Germany BSF.

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

[0049]

[Chemical 7]

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

[0051]

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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, a soft sliding fiber can be obtained like the above composition. 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 content 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 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.

Perfluoro-based 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, and among them, 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 may be mentioned as examples of combinations in the resin composition used in 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 above powdered talc
A mixture containing 10 to 40% by weight of a calcium powder filler in place of the above.

A mixture 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 compounded in place of the carbon fibers of 5 to 45% by weight, and calcium talc powder 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 is used as an additive other than the above-mentioned additives within a range that does not impair the effects of the present invention, for example, for the purpose of improving self-lubricating property, mechanical strength, thermal stability and coloring. 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 of adding various kinds of additives to these heat-resistant resins is not particularly limited, and a commonly-used method such as 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 a drying treatment to the same extent as the heat treatment described later 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 during high temperature use by removing heat distortion and strain during 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 thermal history applied to the resin is considered to be unfavorable, and it is considered to be unfavorable. 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 in 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 performing 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 progressed 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.
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.

[0089]

EXAMPLE A durability test of the seal ring 21 of the present invention was conducted.

(Example 1) PEEK (IC, UK,
Eye company: VICTREX-PEEK150P) 50w
20% by weight of carbon fiber (M207S, manufactured by Kureha Chemical Co., Ltd., average fiber diameter 14.5 μm, aspect ratio 48) at t%, P
1 wt% of TFE (manufactured by Kitamura: 300H) and 20 wt% of talc (Matsumura Sangyo: Crown talc, average particle size 11 μm) as a filler were used, and FIG.
The seal ring 21 having the shape of the first embodiment shown in (1) was obtained by injection molding. The cross section of the seal ring 21 is
It was rectangular and had an outer diameter of 45 mm, a ring width of 2.4 mm, a ring wall thickness of 2.3 mm, a peripheral seal surface 25 width of 1.5 mm, and a seal surface 24 width of 1.8 mm.

The lubricating groove 22 has a depth of 0.1 mm and a width of 0.1 m.
It was formed in three places over the entire circumference of m, and the positions of the lubrication grooves 22 were formed on the seal surfaces 24 on both sides with a shift of about 10 °. The cross-sectional shape of the lubricating groove 22 was trapezoidal as shown in FIG. 1C, and θ was 150 °. In addition, the corners of each lubrication groove 22 were crowned. In addition, burrs formed during molding were removed by barrel processing.

The above seal ring 21 was subjected to a durability test, and the rotational torque, the wear of the ring side surface and the wear amount of the mating shaft groove were measured. The material of the shaft was aluminum alloy ADC12 for die casting. The results of the durability test are shown in Table 1.

The conditions of the durability test are as follows. Oil pressure: 0.8 MPa Rotation speed: 7000 rpm Temperature: 120 ° C. Time: 100 hr Lubricant: Oil for automatic transmission Dexiron II cylinder (rotation): S45C manufactured by Showa Shell Sekiyu KK: Shaft (fixed): ADC12.

Comparative Example 1 A seal ring made of the same material as in Example 1 has an outer diameter of 45 mm and a sectional shape of 2.3 mm × 2.4.
A rectangular shape of mm having a lubricating groove angle θ ′ = 90 ° as shown in FIG. 11 was obtained. Also in this case, the burr was removed by the barrel treatment. A durability test was performed under the same conditions as in Example 1. Table 1 shows the results.

[0095]

[Table 1]

(Results) In the embodiment, the rotation torque is not inferior to that in the comparative example, and the wear of the ring side surface and the mating groove is small. This is because the oil leaks inward and outward through the lubricating groove 22 that penetrates inward and outward, so that an oil film is formed over the entire width of the side surface of the ring over the entire circumference, and abrasion powder and foreign matter are easily removed due to oil leakage. It is due to. Further, the leak amount is very small, and the sealing property is not impaired.

Further, the workability of deburring can be improved, and the efficiency of productivity can be improved.

[0098]

Since the seal ring of the present invention is as described above, since the lubricant leaks inward and outward from the seal surface on the side of the ring to the extent that the lubricant does not impair the sealing performance through the lubricating groove. By the relative rotation with respect to each other, a lubricating film is formed over the entire width of the sealing surface over the entire circumference.

Therefore, the lubricity over the entire sealing surface is improved, the wear resistance is improved, and the mating material is not worn.

When the amount of the surrounding lubricant is reduced, the lubricant is replenished, and smooth rotation is maintained for a long time.

Further, in the first embodiment, since the angle between the sealing surface of the seal ring and the surface of the lubricating groove at the boundary between the sealing surface of the seal ring and the lubricating groove is an obtuse angle,
Burrs during injection molding can be easily removed.

Furthermore, in the second to fourth embodiments, by forming the step portions at the four corners, the burr at the time of injection molding does not block the lubrication groove, and the step portion is not formed. Since the sliding contact area with the mating material is reduced, the rotating torque is also reduced.

[Brief description of drawings]

FIG. 1A is a front view of the first embodiment, FIG. 1B is a partially enlarged front view of the same, and FIG. 1C is a partially enlarged plan view of the same. (E) (b) sectional view taken on the line ee of FIG.

2A is a front view of the second embodiment; FIG. 2B is a partially enlarged front view of the same. FIG. 2C is a partially enlarged plan view of the same. (E) (b) sectional view taken on line ee (f) (d) partially enlarged sectional view

FIG. 3 is a sectional view of the second embodiment during molding.

FIG. 4A is a partially enlarged front view of the third embodiment, and FIG. 4B is a sectional view of the same.

FIG. 5A is a partially enlarged front view of the fourth embodiment. FIG. 5B is a sectional view of the above.

6A to 6H are cross-sectional views showing cross-sectional shapes of lubricating grooves.

FIG. 7 is a perspective view showing a modified example of (a) to (d) lubricating grooves.

FIG. 8 is an enlarged sectional view of a conventional example in use.

9A is a partially enlarged front view of a conventional example, and FIG. 9B is a sectional view of the same.

FIG. 10A is a partially enlarged front view of another conventional example. FIG. 10B is a sectional view of the same.

FIG. 11A is a partially enlarged front view of another conventional example. FIG. 11B is a sectional view of the same.

12A is a partially enlarged front view of another conventional example, FIG. 12B is a sectional view taken along line bb of FIG. 12A, and FIG.

FIG. 13 is an enlarged cross-sectional view of a conventional example during molding.

[Explanation of symbols]

 1 Seal Ring 2 Shaft 3 Circumferential Groove 4 Cylinder 5 Sealing Surface 6 Recess 7 Lubricating Groove 8 Lubricating Groove 9 Lubricating Groove 10 Outer Peripheral Sealing Surface 11 Mold 12 Mating Surface 13 Burr 21 Seal Ring 22 Lubricating Groove 23 Fitting 24 Sealing Surface 25 Outer peripheral sealing surface 26 Stepped portions 27, 27 'Right angle surface 28 Sloping surface 29 Mold 31 Mating surface 32 Burr 33 Circumferential groove 34 Outer radial groove 35 Inner diameter groove 36 Inner peripheral seal surface

Claims (1)

[Claims] 1. A seal ring in which a sealing surface is formed on both side surfaces of the ring, and a lubricating groove is formed in a penetrating manner from the inner periphery to the outer periphery of the sealing surface, wherein the seal is formed at a boundary between the sealing surface and the lubricating groove. A seal ring characterized in that an angle formed between a surface and the surface of the lubricating groove is an obtuse angle.