JP4962062B2 - Seal ring and seal ring manufacturing method - Google Patents

Description

  The present invention relates to a seal ring and a method for manufacturing the seal ring.

  Conventionally, in order to seal an annular gap between a shaft hole and a shaft, there is known a seal ring that is used by being mounted in a groove provided on either surface of the shaft hole or the shaft. It is used in various hydraulic equipment such as AT (automatic transmission).

  A seal ring 100 shown in FIG. 10 seals an annular gap between a housing 200 provided with a shaft hole and a shaft 300 inserted into the shaft hole, and an annular groove 301 provided in the shaft 300. Used by being attached to.

  A seal ring 100 made of a resin material is used to seal the first seal surface 101 for sealing the side wall surface of the annular groove 301 provided in the shaft 300 and the inner peripheral surface of the shaft hole provided in the housing 200. A second seal surface 102.

  When pressure is applied from the sealed fluid side O toward the non-sealed fluid side A from the direction of the arrow P in FIG. 10, the seal ring 100 is pressed against the non-sealed fluid side A, so that the first seal surface 101 has an annular groove. The side wall surface of 301 is pressed, and the second seal surface 102 presses the inner peripheral surface of the shaft hole provided in the housing 200 facing the annular groove 301, and seals at each position. In this way, leakage of the sealed fluid to the non-sealed fluid side A is prevented.

  Such a seal ring 100 is basically designed so that the first seal surface 101 and the side wall surface of the annular groove 301 of the shaft 300 slide during the relative movement of the housing 200 and the shaft 300. .

  Therefore, when a soft material such as aluminum or rolled mild steel is used as the material of the shaft 300 for weight reduction, the sliding surface is worn by sliding with the seal ring 100.

  As a countermeasure against such wear, there are a method of press-fitting hard metal into the groove side wall surface on which the seal ring 100 slides, or a surface treatment to prevent the wear of the sliding surface, but the cost becomes high. End up.

Therefore, a C-ring-shaped annular member having a cut portion is attached to the annular groove, and a protrusion that can be engaged with the cut portion is provided on the side surface of the seal ring. There has been proposed an attachment structure that prevents sliding of a part using a low-quality material (for example, see Patent Document 1).
Japanese Patent No. 3536602 JP-A-11-90961

  However, in the above structure, since the protrusion provided on the side surface of the seal ring that forms the seal surface is fitted to the cut portion of the annular member, the annular groove and the protrusion The contact becomes unstable, and a stable sealing property cannot be obtained.

  In addition, since there is no degree of freedom in setting the shape of the cut portion, it is not possible to employ a special step cut or the like that can cope with a change in circumference due to a temperature change or the like.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to manufacture a seal ring and a seal ring that can obtain a stable sealing performance while suppressing wear due to sliding. It is to provide a method.

In order to achieve the above object, the seal ring in the present invention comprises:
A seal ring that is mounted in an annular groove provided in one of a housing having a shaft hole and a shaft inserted into the shaft hole and seals an annular gap between the two members ;
A cavity for forming the shape of the seal ring body, a gate portion for injecting molten material into the cavity, and a tab for discharging the molten material in the weld portion of the molten material injected into the cavity; In a seal ring manufactured by injection-molding a molded product comprising a seal ring main body part and a molded part formed by the gate part and the tab using a molding die comprising :
In a region other than the sealing surface , a projection is formed which is a molded portion formed by the gate portion or a molded portion formed by the tab, and is fitted into a hole provided in the annular groove.

  According to this configuration, when the housing and the shaft are moved relative to each other, the protrusion fitted in the hole provided in the annular groove engages with the hole, and the seal ring moves together with the member provided with the annular groove. The sliding between the seal ring and the member provided with the annular groove is restricted.

  In addition, since such a sliding restricting means is provided in a region other than the seal surface, the seal surface does not become unstable, and a stable sealing property can be obtained.

  The protrusion may be provided on the inner peripheral surface of the seal ring, and may be fitted into a hole provided on the groove bottom surface of the annular groove provided on the outer peripheral surface of the shaft.

In order to achieve the above object, a method for producing a seal ring according to the present invention includes:
A seal ring that is mounted in an annular groove provided in one member of a housing having a shaft hole and a shaft inserted into the shaft hole, and seals an annular gap between these two members, except for a seal surface In the region, a manufacturing method of a seal ring comprising a protrusion fitted in a hole provided in the annular groove ,
A cavity for forming the shape of the seal ring body,
A gate for injecting molten material into the cavity;
Using a molding die having a tab for discharging the molten material in the weld portion of the molten material injected into the cavity,
Injection molding a molded article comprising a seal ring body portion and a molded portion formed by a gate portion and a tab;
The molding portion formed by the gate portion and / or the molding portion formed by the tab are left as protrusions of the seal ring.

  The part formed by the gate part or tab of the molding die is a part that is originally removed in the seal ring that is the final product. However, by using these as protrusions, the manufacturing cost can be reduced. .

  As described above, according to the present invention, it is possible to obtain a stable sealing property while suppressing wear due to sliding.

  The best mode for carrying out the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

Example 1
First, with reference to FIGS. 1-4, the seal ring which concerns on the 1st Example of this invention is demonstrated. FIG. 1 is a diagram showing an entire seal ring 1 according to the present embodiment, and shows a state in which the seal ring 1 is viewed from the axial direction. FIG. 2 is a cross-sectional view showing a use state of the seal ring 1 according to the present embodiment, and corresponds to the AA cross section of FIG. FIG. 3 is a schematic partially enlarged cross-sectional view showing a use state of the seal ring 1 according to the present embodiment. FIGS. 4A and 4B are schematic perspective views showing examples of the shape of the protrusion 13 of the seal ring 1 according to this embodiment. FIGS. 4C and 4D are corners of the protrusion 13. 4 is a schematic diagram for explaining a relationship between a portion and a corner of a hole 43. FIG.

  The seal ring 1 includes a seal ring body 10 having a substantially rectangular cross section and a plurality of protrusions 13 provided on the inner peripheral surface of the seal ring body 10. The shaft is inserted into the housing 3 and the shaft hole of the housing 3. The annular gap 5 between 4 is sealed.

  The seal ring 1 is made of a meltable resin material, and as the material, for example, polyether ether ketone (PEEK), ethylene-tetrafluoroethylene (ETFE), polyphenylene glycol (PPS), or the like is used.

  The seal ring 1 is mounted in an annular groove 40 provided on the outer peripheral surface of the shaft 4, and when pressure is applied from the sealing target side O (left side in FIG. 2) in the direction of arrow P, the seal ring 1 is unsealed target side A. (Right side in FIG. 2).

  Then, the side surface 11 on the non-sealing target side of the seal ring body 10 is in close contact with the side wall 41 of the annular groove 40, and the outer peripheral surface 12 is in close contact with the inner peripheral surface 32 of the housing 3. Thereby, the leakage to the non-sealing target side A of the sealing target fluid is suppressed.

  As shown in FIG. 1, the seal ring 1 is composed of an end-shaped ring separated at one place on the circumference. By providing such a separation portion S, mounting to the annular groove 40 is facilitated.

  The protrusion 13 provided on the inner peripheral surface of the seal ring main body 10 protrudes inward toward the central axis of the seal ring 1 and is separated from two locations in the vicinity of both ends of the seal ring main body 10 constituting the separation portion S. It is provided in a total of three places, one place on the opposite side of the part S.

  On the other hand, holes 43 are provided in the groove bottom surface of the annular groove 40 of the shaft 4 at positions corresponding to the respective protrusions 13. When the seal ring 1 is attached to the annular groove 40, each protrusion 13 is provided. Are to be fitted into the corresponding holes 43.

In the present embodiment, the protrusion 13 of the seal ring 1 and the hole 43 of the annular groove 40 of the shaft 4 function as means for suppressing the sliding between the seal ring 1 and the shaft 4. That is, when the relative movement between the housing 3 and the shaft 4 occurs, each projection 13 engages with the corresponding hole 43, and the seal ring 1 moves together with the shaft 4. The sliding of the side surface 11 on the non-sealing target side of the ring body 10 and the side wall 41 of the annular groove 40 is suppressed.

  Therefore, even when a soft material such as aluminum or rolled mild steel is adopted as the material of the shaft 4, the sliding of the seal ring 1 and the shaft 4 is suppressed, so that the wear of the shaft 4 can be suppressed. As a result, it is possible to achieve a stable sealing property and a long service life of the device.

  Moreover, since it is not necessary to take measures against wear such as press-fitting hard metal into the groove side wall surface on which the seal ring 1 slides or surface treatment, the cost can be reduced.

  Further, the positions where the protrusions 13 are provided are locations that do not hinder the mounting of the seal ring 1. That is, when the seal ring 1 is mounted, first, the separation portion S is opened, and the protrusion 13 provided on the opposite side of the separation portion S is fitted into the corresponding hole 43. Then, the fitting can be smoothly performed by closing the separating portion S while fitting the protrusion 13 provided in the vicinity of the separating portion S into the corresponding hole 43.

  Further, since the protrusion 13 is not provided on the seal surface, a stable seal surface can be secured, and the separation portion S sealing performance of the seal ring 1 can be kept constant.

  In the seal ring 1 according to the present embodiment, a special step cut that can cope with a change in circumferential length due to a temperature change or the like is adopted in the separation portion S. Further, the hole 43 provided in the annular groove 40 of the shaft 4 is also set to a large size so as to have a clearance with respect to the protrusion 13 of the seal ring 1 so as to be able to cope with a change in circumference.

  Therefore, even if the circumference of the seal ring 1 changes due to thermal expansion or the like, the change in circumference can be absorbed by the special step cut and the clearance between the protrusion 13 and the hole 43, and a stable sealing property is obtained. be able to.

  In the present embodiment, a cylindrical shape as shown in FIG. 4A is adopted as the shape of the protrusion 13, but the shape is not limited to this as long as it can be fitted into the hole 43. For example, a rectangular parallelepiped shape as shown in FIG. Similarly, the hole 43 may have various shapes as appropriate.

  When the hole 43 has a substantially rectangular parallelepiped shape and the protrusion 13 has a rectangular parallelepiped shape as shown in FIG. 4B, the corners of the hole 43 are formed in an R shape. Then, the corners of the projections 13 may interfere with the corners of the holes (locations surrounded by the dotted line in FIG. 4C), and the projections 13 may be damaged.

  Therefore, in this case, the edge of the corner of the protrusion 13 is formed in an R shape, and the corner of the protrusion 13 and the corner of the hole 43 are formed even when R of the protrusion 13 is smaller than R of the hole 43. As shown in FIG. 4D, the R of the protrusion 13 is set to be larger than the R of the hole 43.

  Next, a manufacturing method of the seal ring according to the present embodiment will be described with reference to FIGS.

FIG. 5 is a diagram showing the entire molded product W of the seal ring 1 according to the present embodiment, and shows a state where the molded product W is viewed from the axial direction. FIG. 6 is a view corresponding to the BB cross section of FIG. 5 and is a view for explaining a cross-sectional configuration of a molding die for forming the seal ring 1 according to the present embodiment. In the drawing, the upper side of the mold is a fixed mold 2a and the lower side is a movable mold 2b with a mold opening surface PL (parting line) as a boundary.

  The molding die includes a cavity 20 for forming the shape of the seal ring main body 10, a spool 21 provided in an inner region of the cavity 20, and both ends (separation part S) of the seal ring 1 of the cavity 20 from the spool 21. A runner 22 extending bifurcated toward the vicinity of each portion to be formed, and a gate 23 for connecting the runner 22 and the cavity 20 to inject the molten resin material into the cavity 20 are provided.

  Further, a tab 24 (a cavity connected to the cavity 20) for discharging the molten resin material of the weld portion 26 where the tip of the flow of the molten resin material injected from the gate portion 23 abuts from the cavity 20 is provided. The inner area of the cavity 20 is provided.

  A molded product W molded by this molding die includes a seal ring main body 10 molded with both end portions (separating portions S) being slightly opened, a molding die spool 21, a runner 22, a gate 23, a tab. 24, each molding part 21 ′, 22 ′, 23 ′, 24 ′.

  In the processing from the molded product W to the seal ring 1 as the final product, the molded portions 21 'to 24' are portions that are usually removed. However, in the manufacturing method of the seal ring 1 according to the present embodiment, a part of the molded part 23 ′ and a part of the molded part 24 ′ are left and used as the protrusion 13 of the seal ring 1.

  That is, the cost can be reduced by diverting the portion that is originally removed at the time of the final product as the protrusion 13 as the sliding restraining means.

  It should be noted that a part of the molded part 23 ′ and the molded part 24 ′ left as the protrusions 13 can be appropriately processed and changed in shape as necessary. Further, the arrangement positions of the molded portions 23 ′ and 24 ′ with respect to the seal ring main body 10 are not limited to the positions shown in FIG.

(Example 2)
Next, with reference to FIG. 7 and FIG. 8, the seal ring which concerns on the 2nd Example of this invention is demonstrated. Since the configuration other than the configuration described below is substantially the same as that of the first embodiment, different points will be mainly described here, and the same portions will be denoted by the same reference numerals and detailed description thereof will be given. Is omitted.

  FIG. 7 is a schematic diagram for explaining the seal ring 1 ′ according to the present embodiment. FIG. 7A is a schematic cross-sectional view showing a mounting state of the seal ring 1 ′ according to the present embodiment. And (c) are schematic views showing protrusions provided in the annular groove of the shaft, and (d) and (e) are holes provided on the inner peripheral surface of the seal ring 1 ′ according to the present embodiment, and It is a schematic diagram which shows a recessed part. FIG. 8 is a schematic diagram for explaining the seal ring 1 ′ according to the present embodiment. FIG. 8A is a schematic cross-sectional view showing a mounting state of the seal ring 1 ′ according to the present embodiment. These are schematic diagrams showing protrusions provided in the annular groove of the shaft, and (c) and (d) are schematic views showing holes and recesses provided in the inner peripheral surface of the seal ring 1 'according to the present embodiment. FIG.

  In this embodiment, a hole 15 is provided on the inner peripheral surface of the seal ring 1 ′ instead of the protrusion 13 in the first embodiment, and a protrusion 44 is provided in the annular groove 40 instead of the hole 43. Is provided.

  In this embodiment, the protrusion 44 and the hole 15 constitute a sliding restraining means for restraining the sliding between the seal ring 1 ′ and the annular groove 40.

  The protrusion 44 provided in the annular groove 40 may be provided on the groove bottom as shown in FIG. 7, or may be provided on the groove side wall as shown in FIG. In this case, that is, when the protrusion 44 is provided on the groove side wall, the hole 15 is provided on the side surface 11 of the seal ring 1 ′. Alternatively, as shown in FIG. 8 (d), a recess 14 into which the protrusion 44 can be fitted may be provided on the inner periphery of the seal ring 1 '.

  The hole 15 provided in the inner peripheral surface of the seal ring has a shape that can engage with the protrusion 44 and can regulate the sliding between the seal ring 1 ′ and the shaft 4. It is not particularly limited. Therefore, when the protrusion 44 is provided on the groove bottom, a recess 14 into which the protrusion 44 can be fitted may be provided instead of the hole 15 as shown in FIGS.

  Further, when the recess 14 is provided, the shape of the protrusion provided on the groove bottom is as shown in FIG. 7C instead of the cylindrical protrusion 44 as shown in FIGS. 7A and 7B. It may be a rectangular parallelepiped protrusion 44 '.

(Example 3)
Next, a seal ring according to a third embodiment of the present invention will be described with reference to FIG. Since the configuration other than the configuration described below is substantially the same as the above-described embodiment, the description will focus on the different points, the same portions will be denoted by the same reference numerals, and detailed description thereof will be omitted. To do.

  FIG. 9 is a schematic diagram for explaining the seal ring 1 ″ according to the present embodiment, and FIG. 9A is a schematic cross-sectional view illustrating a mounting state of the seal ring 1 ″ according to the present embodiment. (b) is a schematic diagram showing the protrusion 33 provided on the inner peripheral surface of the housing 3, and (c) shows the hole 16 provided on the outer peripheral surface 12 of the seal ring 1 '' according to the present embodiment. It is a schematic diagram.

  In this embodiment, instead of providing a projection in the annular groove 40, a projection 33 is provided on the inner peripheral surface of the housing 3, and instead of providing a hole in the inner peripheral surface of the seal ring ″, a projection is formed on the outer peripheral surface 12. A hole 16 corresponding to 33 is provided.

  In the present embodiment, the protrusion 33 and the hole 16 suppress the sliding between the seal ring 1 ″ and the inner peripheral surface of the housing 3.

  That is, the sliding restraining means according to the present embodiment is intended not to restrain the sliding between the seal ring ″ and the shaft 4 but to restrain the sliding between the sealing ring ″ and the housing 3. Therefore, in the present embodiment, a soft material such as aluminum or rolled mild steel can be adopted as the material of the housing 3, and the weight of the device can be reduced.

It is a mimetic diagram showing the whole seal ring concerning the 1st example. It is typical sectional drawing which shows the use condition of the seal ring which concerns on a 1st Example. It is a schematic diagram which shows the use condition of the seal ring which concerns on a 1st Example. It is a schematic diagram which shows the protrusion of the seal ring which concerns on a 1st Example. It is a schematic diagram which shows the whole molded product of the seal ring which concerns on a 1st Example. It is typical sectional drawing explaining the shaping die for shape | molding the seal ring which concerns on a 1st Example. It is a schematic diagram explaining the seal ring which concerns on a 2nd Example. It is a schematic diagram explaining the seal ring which concerns on a 2nd Example. It is a schematic diagram explaining the seal ring which concerns on a 3rd Example. It is typical sectional drawing which shows a use condition of the seal ring which concerns on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seal ring 10 Seal ring main body 11 Side surface 12 Outer peripheral surface 13 Protrusion 2a Fixed type 2b Movable type 20 Cavity 21 Spool 22 Runner 23 Gate 24 Tab 3 Housing 4 Shaft 40 Annular groove 43 Hole

Claims (4)

A seal ring that is mounted in an annular groove provided in one of a housing having a shaft hole and a shaft inserted into the shaft hole and seals an annular gap between the two members ;
A cavity for forming the shape of the seal ring body, a gate portion for injecting molten material into the cavity, and a tab for discharging the molten material in the weld portion of the molten material injected into the cavity; In a seal ring manufactured by injection-molding a molded product comprising a seal ring main body part and a molded part formed by the gate part and the tab using a molding die comprising :
A seal ring comprising a protrusion that is a molded portion formed by the gate portion or a molded portion formed by the tab and is fitted into a hole provided in the annular groove in a region other than the seal surface.   2. The seal according to claim 1, wherein the protrusion is provided on an inner peripheral surface of the seal ring and is fitted into a hole provided in a groove bottom surface of the annular groove provided on the outer peripheral surface of the shaft. ring. The seal ring according to claim 2, wherein the protrusion is provided in the vicinity of both end portions of the seal ring main body constituting the separation portion of the seal ring and on the opposite side of the separation portion. A seal ring that is mounted in an annular groove provided in one member of a housing having a shaft hole and a shaft inserted into the shaft hole, and seals an annular gap between these two members, except for a seal surface In the region, a manufacturing method of a seal ring comprising a protrusion fitted in a hole provided in the annular groove ,
A cavity for forming the shape of the seal ring body,
A gate for injecting molten material into the cavity;
Using a molding die provided with a tab for discharging the molten material in the weld portion of the molten material injected into the cavity,
Injection-molding a molded product comprising a seal ring main body part and a molded part molded by the gate part and the tab;
A method for manufacturing a seal ring, characterized in that one or both of a molded portion formed by the gate portion and a molded portion formed by the tab are left as the protrusion of the seal ring.

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