JP2017101689A - Seal ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal ring with one cut part in the circumference thereof that can be inserted without causing biting or catching in being inserted into a hole of a mating housing.SOLUTION: The seal ring has a non-circular shape while being opened at the cut part, as a shape when being formed, and used by being contracted into a circular shape, as a use state. The seal ring has a long thin-shaped recessed groove 9 and a small projection piece 10 entering and engaging with the groove at shaft-central orthogonal surface-like first and second corresponding surfaces 41, 42.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a seal ring.

Conventionally, in order to seal a reciprocating motion, a rotational motion, or a location that rotates together with the reciprocating motion, a generally annular seal ring having a cut (abutting portion) at one circumferential position has been used.
As the shape of the abutment portion of this seal ring, a straight cut shape, an angle cut shape, a step cut shape, a multi-step step cut, and the like are known (see Patent Document 1).

JP 2005-337456 A

For example, the above-described seal ring is generally inserted and mounted in a hole of a cylinder (housing) in a state where the seal ring is mounted in an outer circumferential groove of a piston (shaft).
However, the overall outer diameter of the seal ring in a free state is sufficiently larger than the inner diameter of the hole of the cylinder (housing), and is inserted into and attached to the hole while being elastically deformed in the direction of diameter reduction. On the other hand, the conventional seal ring has a poor fit in the abutment, and is caught between the hole opening end of the cylinder (housing) and the corner of the outer circumferential groove of the piston (shaft). ), There was a problem of damage.

Therefore, the present invention comprises an annular overall shape having a cut at one place on the circumference, a ring main body, a first protrusion protruding from the first end of the ring main body, and a first protrusion of the ring main body. In a seal ring having a second convex portion projecting from two end portions, in a closed state, the first corresponding surface portion having a shape orthogonal to the axial center of the first convex portion, and the second convex portion The second corresponding surface portion orthogonal to the axial center is opposed to or in contact with the second corresponding surface portion, and further, the first corresponding surface portion is provided with an elongated concave groove in the circumferential direction, and the second corresponding surface portion is provided with the second corresponding surface portion. It is the structure provided with the engagement small protrusion which penetrates into the said ditch | groove.
Also, the seal ring outer diameter dimension in the diameter expansion restricted state where the engagement small protrusion is locked to the tip of the concave groove is set to be larger by a predetermined small dimension than the seal ring maximum outer diameter dimension when the seal ring is used. Has been.

  According to the present invention, the fitting of the seal ring mating portion (cut) is improved, and a smooth insertion is performed from the opening end of the hole of the cylinder (housing) without causing biting while keeping the cut closed state. Yes) Along with this, it is possible to prevent damage to the first convex portion and the second convex portion of the seal ring.

FIG. 2 is a plan view showing a cut open state according to an embodiment of the invention. It is a top view which shows a break closed state. It is principal part expanded sectional explanatory drawing explaining the state which inserts (attaches) the seal ring from the opening edge of a housing hole. It is a perspective explanatory view explaining that the 1st correspondence surface part and the 2nd correspondence surface part are formed along the axis orthogonal plane. It is a principal part explanatory perspective view. It is a principal part front view of a break open state. It is a partially broken top view which shows a cut open state. It is a figure explaining the shape of a 2nd convex part, Comprising: (A) is a perspective view, (B) is bb sectional drawing of (A), (C) is cc sectional drawing of (A). . It is a figure explaining the shape of a 1st convex part, Comprising: (A) is a perspective view, (B) is bb sectional drawing of (A), (C) is cc sectional drawing of (A). . It is a principal part cross-sectional view. It is principal part cross-sectional explanatory drawing which shows a seal ring use condition. It is a figure explaining the relative positional relationship of a ditch | groove and the engagement protrusion which plunged into the ditch | groove. It is sectional drawing which shows the various modifications of a ring main body. It is principal part sectional drawing which shows another embodiment.

Hereinafter, the present invention will be described in detail based on the illustrated embodiment.
As shown in FIGS. 1, 2, 4 to 7, the seal ring S according to the present invention has an annular overall shape having a cut 5 at one place on the circumference. The seal ring S includes a ring body 1 occupying a central angle slightly smaller than 360 °, and a first end 11 and a second end 12 of the ring body 1 that are protruded in the circumferential direction. A convex portion 21 and a second convex portion 22 are provided.

The seal ring S according to the present invention is made of a resin composition, and is preferably a thermoplastic resin composition such as a PES resin composition and can be integrally formed by injection molding. In the present invention, a part or the whole may be formed by machining. As the resin material, in addition to the above PES resin composition, a PTFE resin composition, a PEEK resin composition, a PPS resin composition, a polyimide resin composition, and the like can also be used.
Then, the seal ring S according to the present invention is used for sealing a reciprocating motion, a rotating motion, or a portion that rotates with the reciprocating motion (see FIG. 3).

6 and 7, a two-dot chain line 31 indicates a boundary surface between the first convex portion 21 and the first end portion 11 (of the ring body 1), and a two-dot chain line 32 indicates the second convex portion. The interface between the part 22 and the second end 12 (of the ring body 1) is shown.
Assuming that the first convex portion 21 and the second convex portion 22 are cut at the boundary surfaces (two-dot chain lines) 31 and 32 in FIGS. 6 and 7, FIG. 9 (A) and FIG. It has a shape as shown in a perspective view. That is, as shown in FIG. 9, the first convex portion 21 has an angle-shaped portion 21A and a rectangular portion 21B from the proximal end to the distal end, and has a stepped surface 2 in the middle in the circumferential direction. As shown in FIG. 8, the second convex portion 22 has an angle-shaped portion 22A and a rectangular portion 22B from the proximal end to the distal end, and has a stepped surface 3 in the middle in the circumferential direction.

As shown in FIGS. 9 and 7, the angle-shaped portion 21A has a cross-sectional shape obtained by cutting out a quarter of a small rectangle including one corner of the ring body 1 if the ring body 1 is a cross-sectional rectangle. It has a recess 6 having a small rectangular cross section.
Further, the circumferential length of the angle-shaped portion 21A and the rectangular portion 21B is 21A ≧ 22B, and the circumferential length of the angle-shaped portion 22A and the rectangular portion 22B is 22A ≧ 21B. The comrades to be combined are equal or do not hit each other, and the sealing property of the joint is obtained.
As shown in FIGS. 8 and 7, if the ring body 1 has a rectangular cross section, it is a cross sectional shape obtained by cutting out a quarter of a small rectangle including the corner portion. It has a recess 7. Further, the circumferential length of the angle-shaped portion 22A is set equal to the circumferential length of the rectangular portion 22B near the tip.

The side surface 6A of the recess 6 of the angle-shaped portion 21A and the one side surface 16 on the inner side in the width direction of the rectangular portion 21B form a continuous plane (same plane). More specifically, assuming that the axis of the seal ring S is Ls, the plane orthogonal to the axis perpendicular to the axis Ls and the continuous plane (same plane) are parallel to each other. If this is defined as an axially orthogonal plane shape, the side surface 6A and the one side surface 16 exist on the same plane orthogonal to the axial center plane.
On the other hand, the side surface 7A of the recess 7 of the angle-shaped portion 22A and the one side surface 17 on the inner side in the width direction of the rectangular portion 22B form a continuous plane (same plane). Then, it can be said that the side surface 7A and the one side surface 17 exist on the same plane orthogonal to the axial center.

2 and FIGS. 5 (B) and 5 (C), from the side surface 16A and the side surface 16 that are orthogonal to the axial center of the first convex portion 21 (shown in FIGS. 6 and 7). The first corresponding surface portion 41, and the second corresponding surface portion 42 formed of the side surface 7A and the one side surface 17 of the second convex portion 22 which are orthogonal to the axial center face each other in close proximity to or in contact with each other.
FIG. 4 is a perspective view illustrating the positions and orientations of the first corresponding surface portion 41 and the second corresponding surface portion 42 (with more attention), and P ₀ is a plane orthogonal to the seal ring axis Ls— When the thickness of the ring body 1 having a rectangular cross section is divided into two equal parts, the first corresponding surface portion 41 and the second corresponding surface portion 42 are located on the axis orthogonal plane P ₀ . Exists. In FIG. 4, a position where the thickness of the seal ring S is cut into two equal parts along the plane P ₀ is indicated by a two-dot chain line 33.
As shown in FIGS. 5 to 12, the first corresponding surface portion 41 is provided with an elongated concave groove 9 along the circumferential direction, and the second corresponding surface portion 42 has an engagement small protrusion 10. Is provided.
The small protrusion 10 enters and engages with the concave groove 9, and the small protrusion 10 is movable in the circumferential direction along the concave groove 9 as shown in FIG.

Here, returning to FIG. 1 and FIG. 2, a description will be given of the point that the overall shape becomes a perfect circle in the closed state. As shown in FIG. 1, the ring body 1 of the seal ring S in which the cut line 5 is in the open state has a portion 13 having a maximum radius of curvature R ₁₃ (the maximum dimension) on the side opposite to the cut line 5. In addition, the curvature radii R ₁ and R ₂ gradually decrease from the portion 13 having the maximum dimension toward each of the first end portion 11 and the second end portion 12 in the circumferential directions M ₁ and M _2. The radius of curvature R ₁₁ , R _{12 of} the first end portion 11 and the second end portion 12 is set to be the minimum dimension, and further, the first convex portion 21 and the second convex portion (which have a small projecting dimension). The radius of curvature of the outer peripheral surface 22 is the same as R ₁₁ and R ₁₂ .
The curvature radii R ₁₃ , R ₁ , R ₂ , R ₁₁ , R ₁₂ are dimensions from the center point O ₁ (axial center Ls) to the outer periphery of the ring body 1 as shown in FIG. .

In the plan view of FIG. 1, the ring body 1 in the open state is 180 ° ± 30 ° with respect to the central point (center point) P ₅ of the cut 5 in the plan view of FIG. Within the range there is a region 13 of maximum dimension. That is, θ shown in FIG. 1 is 30 °, and the portion 13 having the maximum dimension is disposed in the range of 2θ = 60 °. What is necessary is just to select the center angle of the site | part 13 of this largest dimension in the range of 1 degree-60 degrees. (In FIG. 1, L ₀ is a line indicating the diameter including the central point P _5. )

When the seal ring S according to the present invention is manufactured by injection molding of a thermoplastic resin composition, the shape and dimensions of the cavity of the mold, and the seal ring S (see FIG. 1) taken out from the cavity are as follows: A portion 13 having a maximum radius of curvature R ₁₃ is disposed in the outer peripheral shape within a range of ± θ (= ± 30 °) on the opposite side of 180 ° with respect to the cut 5. Set to a non-round shape that gradually decreases toward.
In the state of use--in the state where it is mounted in the seal groove 4B of the piston 4 or the like as shown in FIG .--- the first convex portion 21 and the second convex portion 22 overlap each other as shown in FIG. The closed line is in the closed state, but due to the non-round shape described above in the open state of the cut line shown in FIG. 1, due to the elastic deformation, it becomes a perfect circle with the same radius R ₀ from the center point O ₁ . And in close contact with the inner peripheral surface 28A of the hole 28 of the housing (cylinder barrel) 27 shown in FIG. When deformed from the cut open state (FIG. 1) to the cut closed state (FIG. 2), the portion 13 having the largest dimension is deformed so that the radius of curvature is the largest, and the first end portion 11 and the second end portion 12 side. Hardly deforms. Therefore, the curvature radius R ₀ shown in FIG. 2 is equal to the curvature radii R ₁₁ and R ₁₂ of the end portions 11 and 12 shown in FIG.

Then, the situation in which the small engaging protrusion 10 that has entered the concave groove 9 slides in the circumferential direction in the concave groove 9 is shown in FIG. The following description is based on the positional relationship explanatory diagram.
3 and FIG. 11 show an example of the use state of the seal ring. The tolerance of the inner diameter dimension of the hole 28 of the housing (cylinder barrel) 27, each position in the axial direction of the hole 28 are shown. As shown in FIG. 12, due to variations in the inner diameter of the inner surface, fluctuations in the inner diameter due to thermal expansion and contraction in a large operating temperature range (for example, −40 ° C. to 200 ° C.), wear of the outer peripheral surface 37 of the seal ring the engagement Tosshutsuko 10, a region M ₁₀ between Y ₁ position and Y ₂ position (as indicated by the arrow N _1, N ₂₎ under the sealing ring using state moves.

If it demonstrates corresponding to the example shown in FIG.5, FIG.6, FIG.7, it will be a small protrusion from the state of FIG. 5 (A), FIG. 6, FIG. When 10 is inserted into the concave groove 9, the seal ring S tries to expand its diameter by its own elastic restoring force. However, small Tosshutsuko 10 is engaged with the tip 9A of the groove 9, resiliently expanded seal ring S in Y ₃ position shown in FIG. 5 (B) and 12 is restricted. That is, the Y ₃ position in FIG. 12 is a state in which the small protrusion 10 is locked to the distal end portion 9A, and the diameter expansion restriction state of the seal ring S is maintained.
Further, Y ₂ position of FIG. 12 shows the position of the small Tosshutsuko 10 corresponding to the seal ring maximum outer diameter dimension of the sealing ring use. Further, Y ₃ position indicates the position of the small Tosshutsuko 10 corresponding to the seal ring minimum outer diameter dimension of the sealing ring use. This Y ₃ position corresponding to the minimum outer diameter, small Tosshutsuko 10 to the proximal end 9C of the groove 9 is provided allowance of small dimensions so as not to collide.
Then, the seal ring outside diameter of the locked enlarged restricted state to the tip 9A of the small Tosshutsuko 10 groove 9 (Y ₃ position), a predetermined small than the seal ring maximum outer diameter dimension of the seal ring used state Only the dimensions increase. In other words, the Y ₃ position is slightly closer to the tip side of the concave groove 9 than the Y ₂ position.

7 and FIG. 11, the case where the small protrusion 10 is a round mountain type is shown, and the cross-sectional shape of the concave groove 9 is an arc shape. Then, the height dimension H ₁₀ of the small protrusion ₁₀ is shown in FIG. 11 so that the small protrusion 10 does not unexpectedly leave the concave groove 9 with the seal ring S attached to the seal groove 4B. It is set larger than or at least equal to the gap dimension ΔW corresponding to the difference (T ₄ −Ts) obtained by subtracting the seal ring thickness dimension Ts from the groove width dimension W ₄ . That is, H ₁₀ ≧ ΔW is set.
In the above description, the small protrusion 10 is a round mountain (the cross-sectional shape is a semicircular shape), and the cross-sectional shape of the groove 9 is an arc. However, the small protrusion 10 is a pyramid. As long as it is a mold / pyramidal trapezoidal shape (the cross-sectional shape is triangular, trapezoidal), and the cross-sectional shape of the concave groove 9 is that which locks the small protrusion 10 of the pyramid / pyramidal shape.

  Next, FIG. 13 shows a modification in which the cross-sectional shape of the ring body 1 is different, and small square notches 15 and 15 are formed on the inner peripheral surface side corners 14 and 14 as shown in FIG. C chamfers 18 and 18 are formed as shown in FIG. 13B, or round chamfers 19, 19, and 19 are formed as shown in FIG. 13C.

Further, as shown in FIGS. 14A and 14B, the shape of the small protrusion 10 may be a short cylinder, and the cross-sectional shape of the groove 9 may be a square shape.
Further, as shown in FIG. 14 (B), a curved concave surface 24 is formed on the first convex portion 21, and the second convex portion 22 has a curved convex surface as a shape obtained by dividing the elliptical shape into four. The portion 25 is opposed to the recess 24. By the way, as shown in FIG. 14B, the first corresponding surface portion 41 and the second corresponding surface portion 42 that are orthogonal to the axial center are formed even when the curved convex surface portion 25 and the curved concave portion 24 are provided. By this, it is possible to provide the engagement small protrusion 10 and the concave groove 9 similarly to FIGS. As described above, various cross-sectional shapes other than the embodiment shown in FIGS.

  5 to 11, the first convex portion 21 and the second convex portion 22 have a multi-stage shape including the angle-shaped portions 21A and 22A and the rectangular portions 21B and 22B. Each of the two convex portions 22 has the same cross section, and the concave groove 9 and the engagement small protrusion 10 are formed in the first corresponding surface portion 41 and the second corresponding surface portion 42 that are opposed to each other in the shape orthogonal to the axis. Is also preferred.

Next, the operation of the present invention and an example of the assembling method will be described with reference to FIG. 3. First, the seal ring S according to the present invention is placed in the seal groove 4B of the piston 4 as shown in FIG. while the fitting from the cut open state), when the reduced diameter by hand (or working jigs), 5 and (B), Y ₃ position of FIG. 12, and, as shown in the left diagram of FIG. 3 The small projecting element 10 engages with the concave groove 9 and is engaged with the tip 9A of the concave groove 9, and the outer diameter of the seal ring is a cylinder as shown in the right side of FIG. The size is kept slightly larger than when the seal ring inserted into the hole 28 of the barrel 27 is used.
In particular, as described in FIG. 11, if H ₁₀ ≧ ΔW is set, the seal ring S inserted in the seal groove 4B has a small protrusion 10 in a concave groove as shown in the left side of FIG. If the piston 4 is inserted into the hole 28 as shown by the arrow E, it will not be caught or bitten by the opening inner peripheral edge 28C of the hole 28 (accordingly). , Without being damaged, the seal ring S can be smoothly inserted into the hole 28 as indicated by the arrow F. At that time, the small protrusion 10 located at the Y ₃ position in FIG. 12 moves to the region M ₁₀ of the concave groove 9 between Y ₂ and Y ₁ , in the state shown in the right side of FIG. The seal ring outer peripheral surface 37 is in pressure contact with the inner peripheral surface 28A of the hole portion 28 by the elastic urging force in the radial direction of the seal ring S itself.

In this way, the fitting portion in the mounted state shown in the left side of FIG. 3 fits well and does not pop out from the seal groove 4B, so that the piston 4 can be inserted into the mating housing (cylinder barrel) 27. At this time, it is possible to effectively prevent damage due to the biting (squeezing) of the seal ring S.
In the case of the shape of the embodiment shown in FIG. 5 to FIG. 11, the operation can be quickly performed without worrying about the mounting direction in the seal groove 4B. In other words, there is an advantage that there is no accident of mounting the seal groove 4B in the wrong direction.

  As described in detail above, the present invention has a ring-shaped overall shape having a cut 5 at one place on the circumference, and the ring body 1 and the first protrusion protruding from the first end 11 of the ring body 1. In a seal ring having a portion 21 and a second convex portion 22 projecting from the second end portion 12 of the ring body 1, the axially orthogonal plane of the first convex portion 21 is in a closed state. The first corresponding surface portion 41 and the second corresponding surface portion 42 having a shape orthogonal to the axial center of the second convex portion 22 face each other in close proximity to or in contact with each other, and are further opposed to the first corresponding surface portion 41 in the circumferential direction. Since the elongated concave groove 9 is provided, and the second corresponding surface portion 42 is provided with an engaging small protrusion 10 that enters the concave groove 9, the piston groove or the like to the seal groove 4 </ b> B is provided. The fitting part (cut 5) in the mounted state is well stored, can stably hold a slightly reduced diameter state, and the mating housing (cylinder barrel) ), Etc., can be prevented from being damaged by being caught or pinched. Further, thermal contraction / expansion due to the influence of the use temperature can be sufficiently absorbed by the engagement of the elongated groove 9 and the small protrusion 10 in the circumferential direction. Therefore, it can be used for sealing of rotary motion, reciprocating motion, or parts that perform reciprocating motion together with rotary motion. Is also applicable.

Also, the seal ring outer diameter dimension in the diameter expansion restricted state in which the engagement small protrusion 10 is engaged with the tip end portion 9A of the concave groove 9 is smaller than the seal ring maximum outer diameter dimension in the seal ring use state. Since it is configured so as to be large only, there is an advantage that it can be smoothly inserted into the hole 28 without causing biting or pinching.
The seal ring of the present invention is suitable as a seal ring for sealing a rotary motion, a reciprocating motion, or a portion that reciprocates with the rotary motion. For example, a clutch fastening piston, a centrifugal cancel piston, a pulley driving piston, an oil It is useful for sealing rings for sealing pumps and compressors.

1 Ring body 5 Cut 9 Groove 9A Tip
10 Engaging small protrusion
11 First end
12 Second end
21 1st convex part
22 Second convex part
41 First corresponding surface
42 Second corresponding surface part S Seal ring

Claims (2)

A ring-shaped overall shape having a cut (5) at one place on the circumference, a ring main body (1), and a first protrusion (1) projecting from the first end (11) of the ring main body (1) ( 21) and a seal ring having a second protrusion (22) projecting from the second end (12) of the ring body (1),
In the closed state, the first corresponding surface portion (41) of the first convex portion (21) orthogonal to the axial center and the second corresponding surface portion of the second convex portion (22) orthogonal to the axial center (42) ) In close proximity to or in contact with each other, and further, the first corresponding surface portion (41) is provided with an elongated concave groove (9) in the circumferential direction, and the second corresponding surface portion (42) is provided with An engagement small protrusion (10) that enters the concave groove (9) is provided.   The seal ring outer diameter dimension in the diameter expansion restricted state where the engagement small protrusion (10) is locked to the tip end portion (9A) of the concave groove (9) is larger than the seal ring maximum outer diameter dimension in the seal ring use state. The seal ring according to claim 1, wherein the seal ring is set larger by a predetermined small dimension.

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