JP2009250421A - Sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing device having an excellent mounting property and an improved sealability, while having improved noise reduction effect. <P>SOLUTION: The sealing device 1 comprises: an annular belleville spring 2; and a rubber-like elastic body 3 baked and fixed to an inner circumferential face of the belleville spring 2. The rubber-like elastic body 3 includes: a first seal part 31 extending from the inner circumferential face of the belleville spring 2 in a shaft center direction and toward an opposed face 51a of a flange part 51, and brought into close-contact with the opposed face 51a; and a second sealing part 32 extending from the inner circumferential face of the belleville spring 2 in a shaft center direction and toward an open end face 61 of a cylinder head 60, and brought into close-contact with the open end face 61. Inner peripheral face sides of the first seal part 31 and the second seal part 32 are provided with a plurality of projections 33, 34 abutting on an outer peripheral surface of a shaft part 52 of an injector 50, and are equally disposed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sealing device that prevents leakage of a sealing fluid such as gas.

  When the injector is fastened and fixed to the cylinder head of the engine, it is necessary to prevent the combustion gas from leaking from the fastening portion.

  Conventionally, as this type of combustion gas seal for an injector, for example, there are those shown in FIGS.

  FIG. 5 is a schematic configuration diagram showing a state where the injector is attached to the cylinder head of the engine. FIG. 6 is a schematic diagram for explaining a seal structure of a combustion gas seal for an injector according to the prior art.

  Here, when the injector 150 is attached to the cylinder head 160 of the engine, it is necessary to prevent the combustion gas from leaking from the vicinity of the attachment portion of the injector 150.

  Therefore, conventionally, as shown in FIG. 5, the washer-shaped seals 100 and 200 are provided at two locations in the attachment portion of the injector 150 to prevent the combustion gas from leaking.

These seals 100 and 200 are made of metal such as copper, and a fastening force obtained when the injector 150 is attached to the cylinder head 160 of the engine (for example, as shown in FIG. The fastening force obtained by pressing the injector 150 with the clamp 70) is clamped with the clamping force Q as shown in FIG.
JP 2002-257239 A

  However, in the case of the prior art as described above, the following problems have occurred.

  As described above, since the metal washer-like seals 100 and 200 are sealed using the clamping force, vibrations from the engine or the like are transmitted to the seals 100 and 200, and a loud sound is produced at the sealed portion. This was a cause of noise.

  In addition, since the fastening force is reduced due to a load due to vibration or heat, the sealing performance has deteriorated over time.

  An object of the present invention is to provide a sealing device that improves the soundproofing effect, has excellent wearability, and has improved sealing performance.

In order to achieve the above object, the present invention has a first member having a shaft portion and a flange portion protruding outward from the shaft portion, and an insertion hole into which the shaft portion of the first member is inserted. A sealing device for sealing a gap between the second member,
An annular metal leaf spring sandwiched between opposed surfaces of the flange portion of the first member and the opening end surface facing the insertion hole of the second member, and an elastic seal portion (for sealing each of the opposed surfaces) The first seal portion and the second seal portion) are provided.

  Therefore, it is possible to prevent noise due to vibration by performing sealing with an elastic body. Moreover, durability was obtained by providing not only an elastic body but also a metal leaf spring.

  Moreover, in this invention, when a metal leaf | plate spring was inserted | pinched between the said opposing surfaces, it was set as the structure which can restrict | limit the load (load) which a 1st seal part and a 2nd seal part receive from this opposing surface.

  That is, the metal plate spring is sandwiched between the opposing surfaces, and the distance between the opposing surfaces is defined by the metal plate spring, thereby limiting the load received by the first seal portion and the second seal portion. did.

  Specifically, in the invention according to claim 1, the first seal portion is configured to extend from the inner peripheral surface of the metal plate spring toward the opposing surface on the axial direction and the flange portion side. The seal portion is configured to extend from the inner peripheral surface of the metal plate spring in the axial direction and toward the opening end surface of the second member, so that the distance between the opposing surfaces is the smallest plate thickness of the metal plate spring. It becomes a distance, and the load received by the first seal portion and the second seal portion is limited.

  In the invention according to claim 4, step portions (first step portion and second step portion) are provided on the outer peripheral side and the inner peripheral side of the metal leaf spring, respectively, and the first seal portion is the outer periphery of the metal leaf spring. By fixing the second seal portion to the inner peripheral surface and the second step portion of the metal leaf spring, each seal portion is accommodated in the step portion, and the distance between the facing surfaces is The load applied to the first seal portion and the second seal portion is limited by the metal leaf spring.

  Moreover, in this invention, it was set as the structure which provides the some protrusion contact | abutted with respect to the axial part of the 1st member. That is, in the invention according to claim 1, the plurality of protrusions are provided on at least one of the first seal portion and the second seal portion. In the invention according to claim 4, the plurality of protrusions are provided on the second seal portion.

  With this configuration, the plurality of protrusions abut on the shaft portion of the first shaft member, and thus the sealing device can be held on the shaft portion. Therefore, the sealing device can be attached to the shaft portion of the first member in advance. Accordingly, since the shaft portion of the first member can be inserted into the insertion hole of the second member in a state where the sealing device is mounted on the shaft portion of the first member, the seal portion is connected to the shaft portion of the first member and the second member. It is possible to prevent biting between the insertion hole and the mountability.

  Further, by providing a plurality of protrusions that come into contact with the shaft portion of the first member, the coaxiality between the shaft portion of the first member and the sealing device is improved.

  In addition, it is preferable that the first seal portion and the second seal portion in the invention according to claim 1 have a pressure receiving surface that receives a fluid pressure by the fluid to be sealed and increases an adhesion force to the seal portion.

  Thereby, what is called a self-seal function is exhibited and sealing performance improves.

  As described above, according to the present invention, it is possible to improve the soundproofing effect, to be excellent in wearability, and to improve the sealing performance.

  Exemplary embodiments of the present invention will be 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. Absent.

  In the following embodiments, a sealing device used as an injector combustion gas seal for preventing leakage of combustion gas at a fastening portion of an injector attached to an engine cylinder head will be described as an example.

(First embodiment)
With reference to FIGS. 1-3, the sealing device which concerns on the 1st Embodiment of this invention is demonstrated. FIG. 1 is a schematic cross-sectional view of a sealing device according to a first embodiment of the present invention. FIG. 2 is a schematic cross-sectional enlarged view showing a mounting state of the sealing device according to the first embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing a mounted state of the sealing device according to the first embodiment of the present invention. Note that the part circled in FIG. 3 corresponds to FIG.

  The sealing device 1 according to the present embodiment is used to prevent combustion gas leakage at a fastening portion of an injector 50 attached to a cylinder head 60 of an engine.

  The injector 50 includes a shaft portion 52 and a flange portion 51 protruding outward from the shaft portion 52. On the other hand, the cylinder head 60 has an insertion hole 62 into which the shaft portion 52 of the injector 50 is inserted.

  Then, with the shaft portion 52 of the injector 50 being inserted into the insertion hole 62 of the cylinder head 60, the injector 50 is connected to the cylinder head by a fastening method (not shown) (for example, a clamp as shown in FIG. 5). 60 is fastened.

  The sealing device 1 is mounted between the opposing surfaces between the flange portion 51 of the injector 50 and the opening end surface 61 facing the insertion hole 62 of the cylinder head 60, so that the injector attached to the cylinder head 60 of the engine is installed. Combustion gas leakage at 50 fastening portions is prevented.

  As shown in FIGS. 1 and 2, the sealing device 1 according to the present embodiment includes an annular disc spring 2 as a metal leaf spring, and a rubber-like elastic body 3 that is baked and fixed to the inner peripheral surface of the disc spring 2. And.

  The rubber-like elastic body 3 extends from the inner peripheral surface of the disc spring 2 in the axial direction and toward the facing surface 51a of the flange portion 51 with respect to the opening end surface 61 of the cylinder head 60, and is in close contact with the facing surface 51a. It has the 1st seal | sticker part 31 to seal.

  Furthermore, the rubber-like elastic body 3 extends from the inner peripheral surface of the disc spring 2 in the axial direction and toward the opening end surface 61 of the cylinder head 60, and a second seal portion 32 that seals in close contact with the opening end surface 61. Have.

  As shown in FIG. 2, the sealing device 1 is sandwiched between the opposed surface 51 a of the injector 50 and the opening end surface 61 of the cylinder head 60 by fastening the injector 50 to the cylinder head 60.

  As a result, the disc spring 2 is elastically deformed by a compressive force and generates an elastic repulsive force with respect to each opposing surface, so that it is fixed to the opposing surface 51 a of the injector 50 and the opening end surface 61 of the cylinder head 60. .

  Since the rubber-like elastic body 3 is sandwiched and compressed by the opposed surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60, the first seal portion 31 is moved to the opposed surface of the injector 50 by an elastic repulsive force. A seal surface is formed with respect to 51 a, and the second seal portion 32 forms a seal surface with respect to the opening end surface 61 of the cylinder head 60.

  With the configuration as described above, since the disc spring 2 that is a metal leaf spring is provided, the same durability as when a metal washer-like seal is provided as in the prior art can be obtained.

  Further, since the rubber-like elastic body 3 is pressed against the flange portion 51 of the injector 50 and the opening end surface 61 of the cylinder head 60 to perform sealing, it exhibits stable sealing performance against vibration and heat load, Even when vibration is transmitted, it is possible to reduce the generation of noise.

  Since the rubber-like elastic body 3 is baked on the disc spring 2, it is not necessary to provide a dedicated mounting groove for the injector or the cylinder head as in the case of providing a known seal such as an O-ring.

  In addition, the disc spring 2 has an inclination that is convex toward the inner diameter side by θ as shown in FIG. 1 when no load is applied. Accordingly, when sandwiched between the opposed surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60, the elastic repulsive force increases as θ decreases.

  With such a structure, when the disc spring 2 has an inclination θ of zero, as shown in FIG. 2, one surface 21 of the disc spring 2 comes into surface contact with the opposed surface 51a of the injector 50, and the other surface. 22 is in surface contact with the open end surface 61 of the cylinder head 60.

  Therefore, the gap between the facing surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60 does not become smaller than the plate thickness of the disc spring 2 itself.

  That is, the disc spring 2 has a structure that regulates that the gap between the opposed surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60 does not become a certain value (plate thickness of the disc spring 2 itself) or less. Yes.

  With the above configuration, even when the compressive load on the fuel pressure side inside the injector 50 increases, the gap between the opposed surface 51a of the injector 50 and the open end surface 61 of the cylinder head 60 is maintained at a certain value or more. The load that the rubber-like elastic body 3 receives (the load due to the load) is limited.

  Accordingly, it is possible to prevent the rubber-like elastic body 3 from being damaged and the rubber-like elastic body 3 from being peeled off from the disc spring 2.

  Further, the rubber-like elastic body 3 has a U-shaped cross-sectional shape, so that the first seal portion 31 and the second seal portion 32 are respectively provided between the shaft portion 52 of the injector 50 and the insertion hole 62 of the cylinder head 60. The pressure receiving surfaces 35 and 36 for increasing the adhesion force to the respective seal surfaces by receiving the fluid pressure from the combustion gas (fluid to be sealed) from the gap are provided.

  Thereby, what is called a self-seal function is exhibited and sealing performance improves.

  Further, in the embodiment of the present invention, a plurality of abutting on the inner peripheral surface side of the first seal portion 31 against the outer peripheral surface of the shaft portion 52 of the injector 50 (contacting with a slight tightening margin). The protrusions 33 are provided at equal intervals. Similarly, on the inner peripheral surface side of the second seal portion 32, a plurality of protrusions 34 that abut against the outer peripheral surface of the shaft portion 52 of the injector 50 (abut so as to have a slight tightening margin) are provided. I tried to provide it.

  By providing the plurality of projections 33 and 34 in this way, the plurality of projections 33 and 34 come into contact with the outer peripheral surface of the shaft portion 52 of the injector 50, so that the sealing device 1 is held by the shaft portion 52. It becomes possible. Therefore, the sealing device 1 can be mounted on the shaft portion 52 of the injector 50 in advance.

  That is, conventionally, the injector is attached to the cylinder head and fastened with the sealing device attached to the cylinder head. In this case, however, the seal portion is formed of a rubber-like elastic body as in the present embodiment. In the case of the sealing device, the seal portion may be caught between the shaft portion of the injector and the insertion hole provided in the cylinder head.

  In contrast, in the present embodiment, as described above, the sealing device 1 is previously attached to the shaft portion 52 of the injector 50, and in this state, the shaft portion 52 of the injector 50 is inserted into the cylinder head 60. The injector 50 can be attached to the cylinder head 60 by being inserted into the hole 62.

  Thereby, it can avoid easily that the rubber-like elastic body 3 is bitten, and it is excellent in mounting property.

  Further, by providing the plurality of protrusions 33 and 34, the coaxiality with respect to the shaft portion 52 of the injector 50 in the state where the sealing device 1 is mounted is excellent.

  Accordingly, since the pressure of the combustion gas is uniformly applied to the entire circumference of the pressure receiving surfaces 35 and 36 of the rubber-like elastic body 3, a stable self-sealing function is exhibited and a stable sealing performance is exhibited.

  In the present embodiment, the configuration in which the plurality of protrusions 33 and 34 are provided in both the first seal portion 31 and the second seal portion 32 is shown. Exhibits the same functions and effects.

(Second Embodiment)
FIG. 4 shows a second embodiment of the present invention. In the first embodiment, the case of the sealing device provided with the disc spring constituted by the metal plate spring having a constant thickness has been described. However, in the present embodiment, the metal plate spring constituted by the step is used. The case of a sealing device provided with a disc spring will be described.

  FIG. 4 is a schematic cross-sectional view of a sealing device according to the second embodiment of the present invention.

  The sealing device 1a according to the present embodiment includes an annular disc spring 2a as a metal leaf spring, a first seal portion 31a that is baked and fixed to one surface of the disc spring 2a, and the other surface of the disc spring 2a. And a second seal portion 32a fixed by baking.

The disc spring 2a in the present embodiment is provided with a first step portion 23a that is recessed by one step on the outer peripheral side, and a second step portion 24a that is recessed by one step on the inner peripheral side.

  And in this Embodiment, the 1st seal | sticker part 31a fixed to the outer peripheral surface of the disk spring 2a and the 1st level | step-difference part 23a, and closely_contact | adhering to the said opposing surface 51a of the injector 50 is provided, and the disk spring 2a is provided. A second seal portion 32 a is provided that is fixed to the inner peripheral surface of the first and second stepped portions 24 a and seals in close contact with the opening end surface 61 of the cylinder head 60.

  As in the case of the first embodiment, the sealing device 1a configured as described above is configured such that the opposed surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60 are fastened by fastening the injector 50 to the cylinder head 60. Sandwiched between.

  As a result, the disc spring 2a is elastically deformed by a compressive force to generate an elastic repulsive force on each opposing surface, and is thus fixed to the opposing surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60. .

  And since the 1st seal part 31a and the 2nd seal part 32a are pinched | interposed and compressed by the said opposing surface 51a of the injector 50, and the opening end surface 61 of the cylinder head 60, the 1st seal part 31a is elastically repelled. A seal surface is formed on the facing surface 51 a of the injector 50, and the second seal portion 32 a forms a seal surface on the opening end surface 61 of the cylinder head 60.

  With the configuration as described above, as in the case of the first embodiment, the same durability as when a metal washer-like seal is provided as in the prior art can be obtained, and vibration and heat can be prevented. While exhibiting stable sealing performance against a load, it is possible to reduce the generation of noise even when vibration is transmitted.

  Also in the present embodiment, the whole disc spring has a slope that protrudes toward the inner diameter side by θ as long as the load is not applied, as in the first embodiment. In addition, when sandwiched between the opposed surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60, the elastic repulsive force increases as θ decreases.

  On the other hand, in the present embodiment, when the disc spring 2a has a stepped structure, the disc spring 2a has one surface 21a (the first seal portion 31a is present) when the inclination θ becomes zero. The portion that is not) comes into surface contact with the facing surface 51 a of the injector 50, and the other surface 22 a (portion where the second seal portion 32 a does not exist) comes into surface contact with the opening end surface 61 of the cylinder head 60.

  However, since the first step portion 23 a and the second step portion 24 a are recessed, they do not contact the opposed surface 51 a of the injector 50 and the opening end surface 61 of the cylinder head 60.

  And the clearance gap between the said opposing surface 51a of the injector 50 and the opening end surface 61 of the cylinder head 60 is the distance between the one surface 21a and the other surface 22a of the disc spring 2a (the level | step difference and level | step difference in the disc spring 2a). The thickness of the portion connecting the two is not smaller.

  With the above configuration, even when the compressive load on the fuel pressure side inside the injector 50 increases, the gap between the opposed surface 51a of the injector 50 and the open end surface 61 of the cylinder head 60 is maintained at a certain value or more. The load (load due to load) received by the first seal portion 31a and the second seal portion 32a is limited.

As described above, also in the case of the present embodiment, the load received by the first seal portion 31a and the second seal portion 32a made of a rubber-like elastic body (load due to the load) as in the case of the first embodiment. Can be prevented, and the seal portion can be prevented from being broken or peeled off from the disc spring 2a.

  Also in the present embodiment, as in the case of the first embodiment, the inner surface of the second seal portion 32 abuts against the outer surface of the shaft portion 52 of the injector 50 (slightly A plurality of protrusions 33a (which are in contact with each other so as to have a sufficient tightening allowance) are provided at equal intervals.

  Thereby, similarly to the case of the first embodiment, the sealing device 1a can be mounted on the shaft portion 52 of the injector 50 in advance, and the mounting property is excellent. Moreover, it is excellent in the coaxial degree with respect to the axial part 52 of the injector 50 in the state with which the sealing device 1a was mounted | worn.

It is a typical sectional view of the sealing device concerning a 1st embodiment of the present invention. It is a typical section enlarged view showing the wearing state of the sealing device concerning a 1st embodiment of the present invention. It is typical sectional drawing which shows the mounting state of the sealing device which concerns on the 1st Embodiment of this invention. It is a typical sectional view of the sealing device concerning a 2nd embodiment of the present invention. It is a schematic block diagram which shows a mode that the injector was attached to the cylinder head of the engine. It is a schematic diagram explaining the seal structure of the combustion gas seal for injectors which concerns on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Sealing device 2,2a Belleville spring 23a 1st level | step difference part 24a 2nd level | step difference part 3 Rubber-like elastic body 31 1st seal | sticker part 32 2nd seal | sticker part 31a 1st seal | sticker part 32a 2nd seal | sticker part 33, 34, 33a Protrusion 35, 36 Pressure receiving surface 50 Injector 51 Flange 51a Opposing surface 52 (to the opening end surface 61 of the cylinder head 60) 52 Shaft 60 Cylinder head 61 Opening end surface 62 Insertion hole

Claims (4)

A sealing device that seals a gap between a first member having a shaft portion and a flange portion protruding outward from the shaft portion and a second member having an insertion hole into which the shaft portion of the first member is inserted. There,
An annular metal leaf spring sandwiched between opposing surfaces of the flange portion of the first member and the opening end surface facing the insertion hole of the second member;
A first seal portion made of an elastic body that extends from the inner peripheral surface of the metal leaf spring toward the opposing surface in the axial direction and on the flange portion side, and seals the opposing surface;
A second seal portion made of an elastic body that extends from the inner peripheral surface of the metal leaf spring in the axial direction and toward the opening end surface of the second member, and seals the opening end surface;
A sealing device comprising: a plurality of protrusions provided on at least one of the first seal portion and the second seal portion and abutting against the shaft portion of the first member.   The first seal portion receives fluid pressure due to a fluid to be sealed from a gap between the shaft portion of the first member and the insertion hole of the second member, and adheres to the facing surface on the flange portion side. The sealing device according to claim 1, further comprising a pressure-receiving surface that increases the pressure.   The second seal portion receives fluid pressure due to a fluid to be sealed from a gap between the shaft portion of the first member and the insertion hole of the second member, and adheres to the opening end surface of the second member. The sealing device according to claim 1, further comprising a pressure receiving surface that increases the pressure. A sealing device that seals a gap between a first member having a shaft portion and a flange portion protruding outward from the shaft portion and a second member having an insertion hole into which the shaft portion of the first member is inserted. There,
A first step portion that is sandwiched between opposing surfaces of the flange portion of the first member and an opening end surface facing the insertion hole of the second member and that is not in contact with the opposing surface on the flange portion side is provided on the outer peripheral side. And an annular metal leaf spring having a second step portion that is not in contact with the opening end surface of the second member on the inner peripheral side,
A first seal portion made of an elastic body, which is fixed to the outer peripheral surface of the metal plate spring and the first step portion, and seals the facing surface on the flange portion side;
A second seal portion made of an elastic body, which is fixed to an inner peripheral surface of the metal plate spring and the second stepped portion, and seals the opening end surface of the second member;
A sealing device, comprising: a plurality of protrusions provided on the second seal portion and in contact with the shaft portion of the first member.

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