JP2017101736A - Seal ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal ring capable of restricting sliding wear of the seal ring and a housing.SOLUTION: An outer peripheral surface at an extremity end at one side is provided with a first step part 114X through a cutting part at an abutment part 110, a step surface between the maximum outer diameter part of the outer peripheral surface and the first step part 114X is provided with a first inclination surface 114Xa inclined from an opposite side against an object area to be tight-sealed toward the object area to be tight-sealed to be gradually spaced apart from the most-extremity end part, the extremity end outer peripheral surface of the other side through the cutting part at the abutment part 110 is provided with a second step part 114Y, a step surface between the outer-most diameter part in the outer peripheral surface and the second step part 114Y is provided with a second inclination surface 114Ya inclined from an opposite side of the object area to be tight-sealed toward the object area to be tight-sealed to be gradually spaced apart from the outer-most extremity end part.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a seal ring that seals an annular gap between a shaft and a shaft hole of a housing.

  In automotive automatic transmission (AT) and continuously variable transmission (CVT) for automobiles, a seal ring for sealing an annular gap between a relatively rotating shaft and a housing is provided in order to maintain hydraulic pressure. Yes. As a material used for this seal ring, a resin such as polyether ether ketone resin (PEEK) having a high hardness and excellent heat resistance and capable of injection molding is known. When a seal ring is molded using a material that can be injection molded, there is an advantage that the degree of freedom in shape is high and sliding resistance can be easily reduced.

  Here, in an environment where a seal ring is used, foreign matter such as metal powder exists in oil that is a fluid to be sealed. If such foreign matter enters between the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole of the housing, wear of the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole of the housing is promoted, and the sealing performance is improved. May decrease. It has been found that when an abutment is provided in the seal ring, foreign matter enters from the abutment.

  This point will be described with reference to FIG. FIG. 12 is a perspective view of the vicinity of the abutment portion in a state where the seal ring according to the conventional example is used. In general, in the resin seal ring 500, an abutment portion 510 is provided at one place in the circumferential direction so that the seal ring 500 can be easily attached to the annular groove 210 provided in the shaft 200. Yes. Since the gap S is formed in the joint portion 510, the foreign matter Z enters the gap S. Then, the foreign matter Z that has entered the gap S enters the sliding portion between the outer peripheral surface of the seal ring 500 and the inner peripheral surface of the shaft hole of the housing 300, as indicated by the arrows in the figure.

  In order to suppress the sliding wear of the housing, it is possible to adopt a high hardness material as the housing material. However, in this case, there is a drawback that the cost of the housing becomes high.

JP 2007-239954 A

  An object of the present invention is to provide a seal ring that can suppress sliding wear of the seal ring and the housing.

  The present invention employs the following means in order to solve the above problems.

That is, the seal ring of the present invention is
While an abutment is provided at one place in the circumferential direction,
Fluid pressure in a region to be sealed, which is mounted in an annular groove provided on the outer periphery of the shaft, and is configured to seal the annular gap between the shaft and the housing that rotate relatively to change the fluid pressure. A seal ring for holding
On the outer peripheral surface of the tip on one side via the cutting portion in the joint portion, the shaft of the housing extends from the tip portion (tip portion at the tip on one side) to a constant region in the circumferential direction on the sealing target region side. A first step portion that secures a gap with the inner peripheral surface of the hole is provided, and a step surface between the maximum outer diameter portion and the first step portion of the outer peripheral surface is provided on the side opposite to the region to be sealed. A first inclined surface that is inclined so as to gradually move away from the most distal portion toward the sealing target region side is provided,
On the outer peripheral surface of the tip on the other side through the cutting portion in the joint portion, on the sealing target region side, the shaft of the housing extends from the tip portion (tip portion at the tip on the other side) to a constant region in the circumferential direction. A second step portion for ensuring a gap with the inner peripheral surface of the hole is provided, and a step surface between the maximum outer diameter portion and the second step portion of the outer peripheral surface is provided on the side opposite to the region to be sealed. A second inclined surface that is inclined so as to gradually move away from the most distal portion toward the sealing target region is provided.

  According to the present invention, the first step portion is provided on the outer peripheral surface of the one end via the cutting portion in the joint portion, and the second step portion is provided on the outer peripheral surface of the other end via the cutting portion in the joint portion. Is provided. Therefore, when a foreign material enters the gap at the joint portion, the foreign material is sent to the first step portion or the second step portion. And the foreign material sent to the 1st level | step-difference part is returned by the 1st inclined surface to the sealing object area | region side. Moreover, the foreign material sent to the 2nd level | step-difference part is returned by the 2nd inclined surface to the sealing object area | region side. This prevents foreign matter from entering the sliding portion between the outer peripheral surface of the seal ring and the shaft hole of the housing. Therefore, sliding wear on the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole of the housing can be suppressed.

  As described above, according to the present invention, sliding wear of the seal ring and the housing can be suppressed.

FIG. 1 is a side view of a seal ring according to an embodiment of the present invention. FIG. 2 is a partially enlarged view of a side view of the seal ring according to the embodiment of the present invention. FIG. 3 is a partially enlarged view of a side view of the seal ring according to the embodiment of the present invention. FIG. 4 is a partially enlarged view of the seal ring according to the embodiment of the present invention as viewed from the outer peripheral surface side. FIG. 5 is a partially enlarged view of the seal ring according to the embodiment of the present invention as viewed from the inner peripheral surface side. FIG. 6 is a schematic cross-sectional view showing a state when the seal ring according to the embodiment of the present invention is used. FIG. 7 is a schematic cross-sectional view showing a state in use of the seal ring according to the embodiment of the present invention. FIG. 8 is a schematic cross-sectional view showing a state in use of the seal ring according to the embodiment of the present invention. FIG. 9 is a perspective view of the vicinity of the abutment portion when the seal ring according to the embodiment of the present invention is used. FIG. 10 is a partially enlarged view of a seal ring according to a modification of the present invention as viewed from the outer peripheral surface side. FIG. 11 is a perspective view seen through the vicinity of the joint portion in a state where the seal ring according to the modification of the present invention is used. FIG. 12 is a perspective view of the vicinity of the abutment portion in a state where the seal ring according to the conventional example is used.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. . The seal ring according to the present embodiment is used for sealing an annular gap between a relatively rotating shaft and a housing in order to maintain hydraulic pressure in a transmission such as an AT or CVT for automobiles. It is used. In the following description, “high pressure side” means a side that becomes high when differential pressure occurs on both sides of the seal ring, and “low pressure side” means that differential pressure occurs on both sides of the seal ring. This means the side that is at low pressure.

(Example)
With reference to FIGS. 1-9, the seal ring which concerns on the Example of this invention is demonstrated. FIG. 1 is a side view (schematically shown side view) of a seal ring according to an embodiment of the present invention. FIG. 2 is a partially enlarged view of a side view of the seal ring according to the embodiment of the present invention, and is an enlarged view of a circled portion in FIG. FIG. 3 is a partially enlarged view of a side view of the seal ring according to the embodiment of the present invention, and is an enlarged view of a circled portion in FIG. 1 as viewed from the opposite side. 4 is a partially enlarged view of the seal ring according to the embodiment of the present invention as viewed from the outer peripheral surface side, and is an enlarged view of the circled portion in FIG. 1 as viewed from the outer peripheral surface side. FIG. 5 is a partially enlarged view of the seal ring according to the embodiment of the present invention as viewed from the inner peripheral surface side. FIG. 5 is an enlarged view of the circled portion in FIG. FIGS. 6-8 is typical sectional drawing which shows the state at the time of use of the seal ring which concerns on the Example of this invention. FIG. 6 shows a no-load state, and FIGS. 7 and 8 show a state where a differential pressure is generated. 6 and 7 corresponds to the AA cross-sectional view in FIG. 1, and the seal ring in FIG. 8 corresponds to the BB cross-sectional view in FIG. FIG. 9 is a perspective view of the vicinity of the abutment portion when the seal ring according to the embodiment of the present invention is used.

<Configuration of seal ring>
The seal ring 100 according to the present embodiment is mounted in an annular groove 210 provided on the outer periphery of the shaft 200, and rotates relative to the shaft 200 and the housing 300 (the inner periphery of the shaft hole through which the shaft 200 is inserted. The annular gap between the first and second surfaces is sealed. As a result, the seal ring 100 maintains the fluid pressure in the region to be sealed configured so that the fluid pressure (hydraulic pressure in this embodiment) changes. Here, in this embodiment, the fluid pressure in the region on the right side of the seal ring 100 in FIGS. 6 to 8 is configured to change. The seal ring 100 plays a role of holding the fluid pressure in the region to be sealed on the right side in the drawing via the seal ring 100. In the state where the engine of the automobile is stopped, the fluid pressure in the sealing target region is low and no load is applied. When the engine is started, the fluid pressure in the sealing target region increases. 7 and 8 show a state in which the fluid pressure on the right side in the drawing is higher than the fluid pressure on the left side. Hereinafter, the right side in FIGS. 7 and 8 is referred to as a high pressure side (H), and the left side is referred to as a low pressure side (L).

  The seal ring 100 is made of a resin material such as polyetheretherketone (PEEK) having high hardness and excellent heat resistance. When PEEK is used as the resin material, the seal ring 100 can be obtained by injection molding. Further, the peripheral length of the outer peripheral surface of the seal ring 100 is configured to be shorter than the peripheral length of the inner peripheral surface of the shaft hole of the housing 300 and is configured not to have a tightening allowance. Therefore, when the fluid pressure is not acting, the outer peripheral surface of the seal ring 100 can be separated from the inner peripheral surface of the shaft hole of the housing 300 (see FIG. 6).

The seal ring 100 is provided with an abutment portion 110 at one place in the circumferential direction. A first step 114X, a second step 115Y, a third step 114Y, and a fourth step 115X are provided on the outer peripheral surface of the seal ring 100. Note that the seal ring 100 according to the present embodiment has the above-described joint portion 110, the first step portion 114X, the second step portion 115Y, the third step portion 114Y, and the fourth step portion with respect to the annular member having a rectangular cross section. 115X is formed. However, this is merely an explanation of the shape, and it is always necessary to use an annular member having a rectangular cross section as a material, and the joint portion 110, the first step portion 114X, the second step portion 115Y, the third step portion 114Y, and the fourth step. It does not mean that processing for forming the portion 115X is performed. As described above, when the seal ring 100 is formed by injection molding, the joint portion 110 and the first step portion 114X, the second step portion 115Y, the third step portion 114Y, and the fourth step portion 115X are formed by molding. Can be formed. Thus, a manufacturing method is not specifically limited.

  The configuration of the joint portion 110 according to the present embodiment will be described with reference to FIGS. The joint part 110 according to the present embodiment employs a special step cut cut in a step shape when viewed from either the outer peripheral surface side or both side wall surfaces. In other words, the abutment portion 110 employs a so-called special step cut in which a stepped mating surface (cut surface) is provided when viewed from either the outer peripheral surface side or both side wall surfaces. Accordingly, in the seal ring 100, the first fitting convex portion 111X and the first fitting concave portion 112X are provided on the outer peripheral surface side on one side via the cutting portion (matching surface), and the outer periphery on the other side. On the surface side, a second fitting concave portion 112Y into which the first fitting convex portion 111X is fitted and a second fitting convex portion 111Y to be fitted into the first fitting concave portion 112X are provided. Note that the end surface 113X on the inner peripheral surface side on one side and the end surface 113Y on the inner peripheral side on the other side face each other through the cutting portion. Since the special step cut is a known technique, a detailed description thereof is omitted, but it has a characteristic of maintaining a stable sealing performance even if the circumference of the seal ring 100 is changed due to thermal expansion and contraction. The “cutting portion (mating surface)” includes not only the case of being cut by cutting, but also the case of being obtained by molding.

  And in the seal ring 100 which concerns on a present Example, the front-end | tip part (one side) is in the sealing object area | region side (high pressure side (H)) in the outer peripheral surface of the one side tip through the cutting part in the joint part 110. A first step 114 </ b> X is provided from the tip of the tip of the first step to the constant region in the circumferential direction. The first step portion 114 </ b> X exhibits a function of ensuring a gap with the inner peripheral surface of the shaft hole of the housing 300.

  Of the outer peripheral surface of the seal ring 100, the step surface between the largest outer diameter portion and the first step portion 114X includes a parallel surface 114Xb parallel to the side surface of the seal ring 100 and a first inclined surface inclined with respect to the side surface. 114Xa. The first inclined surface 114Xa is inclined so as to gradually move away from the most distal portion from the side opposite to the sealing target region (low pressure side (L)) toward the sealing target region side (high pressure side (H)).

  Further, in the seal ring 100 according to the present embodiment, the distal end portion (the other side) on the sealing target region side (high pressure side (H)) also on the outer peripheral surface of the distal end on the other side through the cut portion in the joint portion 110. The second step portion 115Y is provided from a tip portion at the tip of the first step) to a constant region in the circumferential direction. The second step portion 115 </ b> Y exhibits a function of ensuring a gap with the inner peripheral surface of the shaft hole of the housing 300.

  Of the outer peripheral surface of the seal ring 100, a step surface between the maximum outer diameter portion and the second step portion 115Y includes a parallel surface 115Yb parallel to the side surface of the seal ring 100 and a second inclined surface inclined with respect to the side surface. 115 Ya. The second inclined surface 115Ya is inclined so as to gradually move away from the most distal portion from the side opposite to the sealing target region (low pressure side (L)) toward the sealing target region side (high pressure side (H)).

The seal ring 100 according to the present embodiment has a symmetrical shape with respect to a center plane in the width direction (a center plane between one side surface and the other side surface). That is, in the seal ring 100 according to the present embodiment, the third step portion 114 </ b> Y is provided on the outer peripheral surface of the other end through the cut portion in the joint portion 110. A step surface between the outermost surface of the seal ring 100 and the third outer step portion 114Y is a parallel surface 114Yb parallel to the side surface of the seal ring 100 and a third surface inclined with respect to the side surface. It is comprised from inclined surface 114Ya. Further, in the seal ring 100 according to the present embodiment, the fourth step portion 115X is provided on the outer peripheral surface of the tip on one side through the cutting portion in the joint portion 110. The step surface between the maximum outer diameter portion and the fourth step portion 115X in the outer peripheral surface of the seal ring 100 is a parallel surface 115Xb parallel to the side surface of the seal ring 100 and a fourth surface inclined with respect to the side surface. And an inclined surface 115Xa.

  Accordingly, when the seal ring 100 is mounted in the annular groove 210 in a state in which the seal ring 100 is mounted in the opposite direction to that in FIG. 8 (the third stepped portion 114Y and the fourth stepped portion 115X are directed to the high pressure side (H)). The third step portion 114Y exhibits the same function as the first step portion 114X, and the fourth step portion 115X exhibits the same function as the second step portion 115Y.

<Mechanism when using seal ring>
In particular, with reference to FIG. 6 to FIG. 9, a mechanism during use of the seal ring 100 according to the present embodiment will be described. In the no-load state where the engine is stopped, as shown in FIG. 6, there is no differential pressure in the left and right regions, so that the seal ring 100 is formed in the annular groove 210 on the left side wall surface in the drawing and the shaft hole of the housing 300. It can be in a state away from the peripheral surface.

  7 to 9 show a state in which the engine is started and a differential pressure is generated via the seal ring 100 (a state in which the pressure on the right side in the drawing is higher than the pressure on the left side). In a state where the engine is started and differential pressure is generated, the seal ring 100 is in close contact with the low-pressure side (L) side wall surface of the annular groove 210 and the inner peripheral surface of the shaft hole of the housing 300.

  Thereby, the annular gap between the relatively rotating shaft 200 and the housing 300 is sealed, and the fluid pressure in the region to be sealed (the region on the high pressure side (H)) configured to change the fluid pressure. Can be held. When the shaft 200 and the housing 300 rotate relatively, the low-pressure side (L) side wall surface of the annular groove 210 and the side surface of the seal ring 100, and the outer peripheral surface of the seal ring 100 and the housing 300. Slide between the inner peripheral surface of the shaft hole.

<Excellent points of seal ring according to this embodiment>
According to the seal ring 100 according to the present embodiment configured as described above, the first step portion 114X is provided on the outer peripheral surface of the tip on one side via the cutting portion in the joint portion 110, and the cut in the joint portion 110 is performed. A second step portion 115Y is provided on the outer peripheral surface of the other end via the portion. Accordingly, when the foreign matter Z enters the gap S in the joint portion 110, the foreign matter Z is sent to the first step portion 114X or the second step portion 115Y (see FIG. 9). And the foreign material Z sent to the 1st level | step-difference part 114X is returned to the sealing object area | region side by the 1st inclined surface 114Xa. Further, the foreign matter Z sent to the second step portion 115Y is returned to the sealing target region side by the second inclined surface 115Ya. As a result, foreign matter is prevented from entering the sliding portion between the outer peripheral surface of the seal ring 100 and the shaft hole of the housing 300. Therefore, sliding wear on the outer peripheral surface of the seal ring 100 and the inner peripheral surface of the shaft hole of the housing 300 can be suppressed.

(Modification)
With reference to FIG.10 and FIG.11, the seal ring which concerns on the modification of this invention is demonstrated. FIG. 10 is a partially enlarged view of a seal ring according to a modification of the present invention as viewed from the outer peripheral surface side. FIG. 11 is a perspective view seen through the vicinity of the joint portion in a state where the seal ring according to the modification of the present invention is used. Since the configuration other than the step surface is the same as that of the above-described embodiment, the same configuration is denoted by the same reference numeral, and the description thereof is omitted as appropriate.

Also in the seal ring 100 according to this modification, the abutment portion 110 is provided at one place in the circumferential direction. A first step 114X, a second step 115Y, a third step 114Y, and a fourth step 115X are provided on the outer peripheral surface of the seal ring 100.

  Similarly to the above-described embodiment, the step surface between the largest outer diameter portion and the first step portion 114X in the outer peripheral surface of the seal ring 100 includes a parallel surface 114Xb parallel to the side surface of the seal ring 100, and the side surface. 1st inclined surface 114Xa which inclines with respect to. In the case of this modification, the parallel surface 114Xb and the first inclined surface 114Xa are connected by the curved surface R.

  Similarly, the step surface between the largest outer diameter portion and the second step portion 115Y on the outer peripheral surface of the seal ring 100 is parallel to the parallel surface 115Yb parallel to the side surface of the seal ring 100 and the second surface inclined with respect to the side surface. 2 inclined surfaces 115Ya. The parallel surface 115Yb and the second inclined surface 115Ya are connected by the curved surface R.

  Similarly, the step surface between the largest outer diameter portion and the third step portion 114Y in the outer peripheral surface of the seal ring 100 is parallel to the parallel surface 114Yb parallel to the side surface of the seal ring 100 and the second surface inclined with respect to the side surface. 3 inclined surfaces 114Ya. The parallel surface 114Yb and the third inclined surface 114Ya are connected by the curved surface R.

  Similarly, the step surface between the maximum outer diameter portion and the fourth step portion 115X on the outer peripheral surface of the seal ring 100 is parallel to the parallel surface 115Xb parallel to the side surface of the seal ring 100 and the second surface inclined with respect to the side surface. 4 inclined surfaces 115Xa. The parallel surface 115Xb and the fourth inclined surface 115Xa are connected by the curved surface R.

  As described above, in the seal ring 100 according to the present modified example, the configuration of the seal ring 100 according to the above-described embodiment is only the point where the parallel surfaces and the inclined surfaces are connected by the curved surface R. Is different. About another structure, it is the same as the structure of the seal ring 100 which concerns on the said Example. Needless to say, the seal ring 100 according to this modification can achieve the same effects as the seal ring 100 according to the above-described embodiment. In the case of this modification, since each parallel surface and each inclined surface are connected by the curved surface R, it is possible to suppress the accumulation of foreign matter Z in the vicinity connecting the parallel surface and the inclined surface. Can do.

100 Seal ring 110 Joint portion 111X First fitting convex portion 111Y Second fitting convex portion 112X First fitting concave portion 112Y Second fitting concave portion 113X, 113Y End surface 114X First stepped portion 114Xa First inclined surface 114Xb Parallel surface 114Y Third step portion 114Ya Third inclined surface 114Yb Parallel surface 115X Fourth step portion 115Xa Fourth inclined surface 115Xb Parallel surface 115Y Second step portion 115Ya Second inclined surface 115Yb Parallel surface 200 Axis 210 Annular groove 300 Housing R Curved surface S Gap Z foreign matter

Claims (1)

While an abutment is provided at one place in the circumferential direction,
Fluid pressure in a region to be sealed, which is mounted in an annular groove provided on the outer periphery of the shaft, and is configured to seal the annular gap between the shaft and the housing that rotate relatively to change the fluid pressure. A seal ring for holding
There is a gap between the outer peripheral surface of the tip on one side through the cut portion in the joint portion and the inner peripheral surface of the shaft hole of the housing from the tip portion to a constant region in the circumferential direction on the sealing target region side. Is provided on the stepped surface between the largest outer diameter portion and the first stepped portion on the outer peripheral surface from the side opposite to the sealing target region toward the sealing target region side. A first inclined surface that is inclined away from the most advanced portion is provided;
A gap is formed between the outer peripheral surface of the tip on the other side through the cut portion in the joint portion and the inner peripheral surface of the shaft hole of the housing from the tip portion to a constant region in the circumferential direction on the sealing target region side. And a step surface between the largest outer diameter portion and the second step portion of the outer peripheral surface is gradually provided from the side opposite to the sealing target region toward the sealing target region side. A seal ring, characterized in that a second inclined surface that is inclined away from the most distal portion is provided.

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