JP2002340191A - Packing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide packing 1 capable of exhibiting sealing performance not only at high pressure time but also at low pressure time, and causing no excess over 100% in a filling rate to an installation space 57 in the floating packing 1 interposed between an outside step part 54 arranged in one member 52 of two members 52 and 55 and an inside step part 56 arranged in the other member 55 so as to be opposed to the outside step part 54. SOLUTION: An outer peripheral projection part 3 is arranged on an outer peripheral surface 2a of the packing 1. This projection part 3 has a crushing margin to a peripheral surface 54a of the outside step part 54. An inner peripheral projection part 4 is arranged on an inner peripheral surface 2b of the packing 1. This projection part 4 has a crushing margin to a peripheral surface 56a of the inside step part 56. One crest-shaped seal part 5 is arranged on a shaft directional end surface 2c of the packing 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packing which is a kind of a sealing device, and more particularly to a floating packing used as a packing for an injector in a fuel injection device.

[0002]

2. Description of the Related Art Conventionally, a floating packing 51 shown in FIG. 5 has been known and is configured as follows.

[0003] First, an annular outer step 54 is provided around the upper end opening of an insertion hole 53 of a housing (intake manifold) 52 in a fuel injection device, and an outer peripheral surface of an injector 55 inserted into the insertion hole 53 is formed. An annular inner step 56 is provided so as to face the outer step 54, and a substantially rectangular section mounting space 57 surrounded by the outer step 54 and the inner step 56 has a substantially rectangular section. The floating packing 51 is inserted.

The outer diameter d ₁ of the packing 51 is formed so as not to have a crushing allowance with respect to the peripheral surface 54 a of the outer step 54, and the inner diameter d _{2 of the} packing 51 is also smaller than the outer diameter 54 of the inner step 56. The surface 56a is formed in a size having no crushing allowance. The axial length L of the outer step 54 and the inner step 56 does not have a crushing allowance in a state where the fuel is not subjected to the fuel pressure (hereinafter referred to as fuel pressure) with respect to both end faces 54b and 56b. It is formed in size.

The above-mentioned conventional packing 51 is mounted between the housing 52 and the injector 55 in a float state having no allowance for crushing in the radial direction (inner and outer peripheral directions) and the axial direction (vertical direction). When the fuel pressure is generated from this state in accordance with the fuel injection, the fuel pressure urges the injector 55 downward, so that the axial end faces 58 of the packing 51 are respectively connected to the outer step portions 54.
Alternatively, it is in close contact with the end surfaces 54b, 56b of the inner step portion 56, and thus a sealing effect is exerted.

However, in the above-mentioned conventional packing 51, the sealing effect is exerted only in the high pressure state where the fuel pressure acts, and the sealing performance in the low pressure state where the fuel pressure does not act becomes insufficient. In some cases, improvement is required.

In order to improve the sealing performance in the low-pressure state, the packing 51 is pressed against the housing 52 and the injector 55 so that the packing 51 comes into close contact with the housing 52 and the injector 55 not only in the high-pressure state but also in the low-pressure state. However, in the case of the floating type packing 51 whose position with respect to the housing 52 is not fixed, such as the injector 55, it is difficult to set an axial crushing allowance without receiving pressure. .

Further, if the width of the conventional packing 51 is increased without changing the cross-sectional shape of the conventional packing 51 and a radial crushing allowance is set, the packing 5 with respect to the mounting space 57 is provided.
The filling factor of 1 greatly exceeds 100%. Therefore, in this case, inconveniences such as the packing 51 protruding from the mounting space 57 and being damaged may occur.

[0009]

SUMMARY OF THE INVENTION In view of the above, the present invention can exhibit a sealing property not only in a high pressure state but also in a low pressure state, and has a filling rate of more than 100% in a mounting space. An object of the present invention is to provide a packing that does not have any.

[0010]

In order to achieve the above object, a packing according to claim 1 of the present invention is provided so that an outer step provided on one of two members is opposed to the outer step. In the packing interposed between the inner step and the inner step provided on the other member, an outer circumferential projection is provided at or near an axial end on the outer circumferential surface of the packing, and the outer circumferential projection is provided with the outer step. The packing has a crushing allowance of a predetermined size with respect to the peripheral surface, and an inner peripheral projection is provided at or near an axial end of the inner peripheral surface of the packing, and the inner peripheral projection is provided on the inner step. The seal is provided with a crushing allowance of a predetermined size with respect to the peripheral surface of the portion, and furthermore, a seal portion having a mountain-like cross section is provided on the axial end surface of the packing.

According to a second aspect of the present invention, there is provided a gasket having a first stepped portion comprising an outer peripheral surface of an injector and a first axially orthogonal surface extending radially outward from the outer peripheral surface; It is arranged in an annular space formed by a second stepped portion having a peripheral surface and a second axially orthogonal surface extending radially inward from the inner peripheral surface to seal between the housing and the injector. An outer peripheral projection which is in contact with the inner peripheral surface at or near an axial end on an outer peripheral surface of the packing; and an outer peripheral surface at or near an axial end on the inner peripheral surface of the packing. And an inner peripheral projection that abuts with the first axial direction orthogonal surface and a second axial direction orthogonal surface on one end surface of the packing. The outer diameter of the outer peripheral projection is Larger than the inner diameter of the inner peripheral surface,
The outer diameter of the outer peripheral surface of the packing is smaller than the inner diameter of the inner peripheral surface, and the inner diameter of the inner peripheral projection is smaller than the outer diameter of the outer peripheral surface of the injector, and the inner diameter of the inner peripheral surface of the packing. Is characterized by being larger than the outer diameter of the outer peripheral surface.

In the packing according to the first aspect of the present invention having the above structure, an outer peripheral projection is provided at or near the axial end of the outer peripheral surface of the packing, so that the crushing allowance of the outer step portion with respect to the peripheral surface is reduced. In addition to being set, an inner peripheral projection is provided at or near the axial end of the inner peripheral surface of the packing, and a crushing allowance for the peripheral surface of the inner step is set. The initial close contact state with respect to the mounting member is realized by the setting of the crushing allowance. In addition to this, in high pressure conditions,
Since the sealing portion having a single mountain cross section provided on the axial end face of the packing comes into close contact with the end face of the outer step portion or the inner step portion, a weighted close contact with the mounting member is realized.

In addition, in the packing according to the first aspect, the packing is stably held by the mounting member by setting the crushing allowance by the formation of the protrusion, so that the axial length of the packing is reduced. It is possible to set the seal portion shorter than before, and it is sufficient to provide one seal portion on the axial end face of the packing in order to realize the above-mentioned weighted close contact state (formation of a seal portion having one cross section in a mountain shape). ).
It is not necessary to provide two or more seal portions on the axial end face of the packing, and this prevents the improvement of the filling rate. Therefore, a relatively large non-filled space is formed on the inner and outer peripheries of the seal portion having a single mountain cross section.

Further, the present invention has the above configuration.
In the packing according to the present invention, an outer peripheral projection which is in contact with the inner peripheral surface of the housing is provided at or near the axial end of the outer peripheral surface of the packing, and the outer diameter of the outer peripheral projection is larger than the inner diameter of the inner peripheral surface of the housing. It is formed large, and the outer diameter of the outer peripheral surface of the packing is formed smaller than the inner diameter of the inner peripheral surface of the housing, and abuts the outer peripheral surface of the injector at or near the axial end of the inner peripheral surface of the packing. An inner projection is provided, the inner diameter of the inner projection is formed smaller than the outer diameter of the outer peripheral surface of the injector, and the inner diameter of the inner peripheral surface of the packing is formed larger than the outer diameter of the outer peripheral surface of the injector. Again, by setting the squeezing allowance by forming these projections, the initial setting for the mounting members (housing and injector) is performed. Do not close state is realized. In addition, in the high-pressure state, the seal portions having a single cross section provided on both end surfaces in the axial direction of the packing come into close contact with the first orthogonal orthogonal surface and the second axial orthogonal surface, respectively. Therefore, a weighted close contact with the mounting member is realized.

Also, in the packing according to the second aspect, the packing is stably held by the mounting member by setting the crushing allowance by the formation of the projection, so that the length of the packing in the axial direction is made larger than before. Can be set to be short, and one seal portion may be provided on each end face in the axial direction of the packing in order to realize the above-mentioned weighted close contact state (the seal portion having one mountain-shaped cross section). Formation). It is not necessary to provide two or more seal portions on both end surfaces in the axial direction of the packing, and this prevents the improvement of the filling rate. Therefore, a relatively large non-filled space is formed on the inner and outer peripheries of the seal portion having a single mountain cross section.

The present application includes the following technical matters.

That is, in order to achieve the above object, one packing proposed by the present application is characterized in that the packing has a semicircular seal portion on upper and lower surfaces, and has two beads at inner and outer peripheral ends. In addition, in order to add sealing properties on the inner and outer circumferences, the width in the inner and outer circumferential directions is increased, a crushing allowance is provided, and a contact portion with the housing is formed in a protruding shape, and the crushing allowance is provided only with the protruding portion Thus, the cross-sectional area is reduced, and the filling rate is reduced.

If several projections are provided on the inner and outer peripheral surfaces, the filling rate can be reduced while maintaining the stability during mounting. In the embodiment, two projections are provided at the inner and outer peripheral ends. For the above reasons, the packing is stable on the inner and outer peripheral contact surfaces, so that the upper and lower surfaces can be formed one by one, and the filling rate is further reduced.
It can be suppressed to 0% or less.

The shape of the projection is preferably a shape having a large root and a low height in order to prevent the projection from falling or being damaged. Further, it is better to avoid a sharp-pointed shape, since there is a concern that the tip may be damaged. If the shape that satisfies the above is a gentle semicircular shape of R, and if there is a corner at the base (joint between the protruding portion and the flat portion), a crack may be generated from the corner. I decided to connect.

According to the above structure, the floating packing can be provided with a sealing property even in a low pressure state where no pressure is applied, while keeping the filling rate low.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a packing 1 according to an embodiment of the present invention.
2 shows a cross section of the packing 1 in a mounted state.

The packing 1 serves as an injector packing in a fuel injection device, and has an annular outer step (second step) 54 provided on the periphery of an upper end opening of an insertion hole 53 of a housing (intake manifold) 52. A rectangular or substantially rectangular mounting space (annular space) 5 surrounded by an annular inner step (first step) 56 provided on the outer peripheral surface of the injector 55 so as to face the outer step 54.
7 is attached.

The packing 1 according to this embodiment first has an annular packing body 2 having a rectangular or substantially rectangular cross section. The packing body 2 has an outer peripheral projection ( The outer projection 3, the inner projection (inner projection) 4, and the seal portion 5 are integrally formed.

First, annular outer peripheral projections 3 are integrally formed radially outwardly at both axial ends of the outer peripheral surface 2a of the packing body 2 respectively. Outer diameter d ₁ of the packing body part 2 outer stepped portion 54
Of the peripheral surface (inner peripheral surface) is 54a is formed slightly smaller than the inner diameter d ₂ of the outer diameter d ₃ of the outer peripheral protruding portion 3 in the free state before mounting the peripheral surface 54a of the outer stepped portion 54 Is formed larger than the inner diameter dimension d _{2 of the} outer peripheral portion 54, so that the outer peripheral projection 3 abuts on the peripheral surface 54 a of the outer step 54, and the outer peripheral projection 3 further contacts the outer surface 54 a of the outer step 54. A crushing allowance of a predetermined size is set. The cross-sectional shape of the outer peripheral projection 3 is formed in a semi-circular shape or a substantially semi-circular shape, and a root portion thereof is rounded in an arc-shaped cross-section so that cracks do not occur. Although diameter d ₁ of the outer circumferential surface 2a between the pair of projections 3 is formed to a size that does not have a squeeze against the peripheral surface 54a of the outer stepped portion 54 according was described above, shown in FIG. 3 When configured the dimensional difference between the diameter d ₂ of the peripheral surface 54a increases as the protrusion 3 is collapsed when wearing (easily fall in the direction of the arrow), in order to squeeze is no longer ensured correctly, this dimensional difference It is preferable to set as small as possible.

In addition, annular inner peripheral projections 4 are integrally formed radially inward at both axial ends of the inner peripheral surface 2b of the packing body 2 respectively. Although the inner diameter d ₄ of the packing body portion 2 is formed slightly larger than the outer diameter d ₅ of the circumferential surface (outer circumferential surface) 56a of the inner stepped portion 56, the inner peripheral protrusions in the free state before the mounting 4 outer diameter d is the inner diameter _{d 6} of the peripheral surface 56a of the inner stepped portion 56
_{5, the} inner peripheral projection 4 is in contact with the peripheral surface 56a of the inner step 56, and the inner peripheral projection 4 further has a predetermined shape with respect to the peripheral surface 56a of the inner step 56. The size allowance has been set. The cross-sectional shape of the inner peripheral projection 4 is formed in a semicircular or substantially semicircular shape, and its root is rounded in an arc-shaped cross section so as not to cause cracks. The diameter dimension d4 of the inner peripheral surface 2b between the pair of protrusions ₄ is formed to have a size that does not have a squeezing allowance with respect to the peripheral surface 56a of the inner step portion 56 as described above. When configured the dimensional difference between the diameter d ₅ of the circumferential surface 56a increases as shown, (easily fall in the direction of the arrow) protruding portion 4 is lying on the time of mounting, in order to squeeze is no longer ensured correctly, this dimensional difference Is preferably set as small as possible.

An annular seal portion 5 having a cross section of one mountain is integrally formed on both axial end surfaces 2c of the packing body portion 2 toward one or the other in the axial direction. The axial length L ₁ of the packing body portion 2, the end face an end face of the (second axial orthogonal plane) 54b and an inner stepped portion 56 of the outer stepped portion 54 in the low pressure fuel pressure is not applied (the first
Of but axially orthogonal plane) is smaller than the distance L ₂ between 56b, the packing 1 overall axial length L ₃ of including the seal portion 5 in the axial direction both ends or equal to the distance L ₂ The seal portion 5 is formed in the seal portion 5 so that the outer step portion 54 or the inner step portion 56
Is configured so that the crushing margin for the end surfaces 54b and 56b is hardly set. The cross-sectional shape of the seal portion 5 is formed in an arc shape or a substantially arc shape, and the base portion is rounded in an arc shape so as not to cause cracks. The seal portion 5 is arranged at the radial center of the axial end face 2c of the packing body portion 2, and relatively large annular non-filled spaces 6 are formed on the inner and outer circumferences.

When the packing 1 having the above structure is mounted in the mounting space 57 between the housing 52 and the injector 55, annular outer circumferential projections 3 are provided at both axial ends of the outer circumferential surface 2a of the packing body 2 respectively. A crushing allowance of a predetermined size with respect to the peripheral surface 54a of the outer step portion 54 is set, and the inner peripheral surface 2 of the packing body portion 2 is formed.
b, annular inner peripheral projections 4 at both axial ends.
Is provided, and a crushing allowance of a predetermined size with respect to the peripheral surface 56a of the inner step portion 56 is set. Therefore, by setting the crushing allowance by forming the projections 3 and 4, the housing 52 and the injector 55 can be crushed. An initial close state is realized. Therefore, by realizing the initial close contact state, it is possible to ensure the sealing performance in a low pressure state where the fuel pressure does not act.

When the fuel pressure is generated by the injection of the fuel, the fuel pressure urges the injector 55 downward, so that the seal portions 5 provided on the axial end face 2c of the packing body 2 are formed in the outer step. It is relatively close to the end surfaces 54b, 56b of the portion 54 or the inner step 56, so that a weighted close contact with the housing 52 and the injector 55 is realized. Therefore, by realizing the weighted close contact state, it is possible to ensure the sealing property in the high pressure state where the fuel pressure acts.

Therefore, from the above, it is possible to provide the packing 1 which exhibits the sealing performance in both the low pressure state and the high pressure state, and exhibits the sealing performance in accordance with the magnitude of the working pressure.

In addition, in the packing 1 having the above structure, the packing 1 is stably held by the housing 52 and the injector 55 by setting the crushing allowance by forming the projections 3 and 4. end face an axial length L ₁ of the portion 2 in the low-pressure state 54
b, can be shorter than the distance L ₂ between 56b, and the axial end face 2a of the packing body portion 2 may be provided one place a seal 5 so as to achieve the above-mentioned aggravated close state, A relatively large unfilled space 6 is formed on the inner and outer circumferences of the seal portion 5.

Therefore, from the above, the mounting space 5
7, the packing ratio of the packing 1 can be reduced, and in the illustrated example, the packing ratio can be suppressed to about 90 to 98%. Therefore, the packing 1 is not
7 can be prevented from running out and being damaged.

Incidentally, as a comparative example, as shown in FIG.
It has exceeded 0%. Further, as shown in FIG. 4 (B), the seal portion 5 is formed into two ridges, and a relatively deep annular concave portion 7 is provided between the two ridges to reduce the filling rate. In addition, the crushing allowance of the projections 3 and 4 located on the inner and outer peripheries is reduced, and a situation occurs in which the sealing performance is reduced. Therefore, it is preferable that the seal portion 5 has a single mountain shape.

[0034]

The present invention has the following effects.

First, in the packing according to the first aspect of the present invention having the above structure, an outer peripheral projection is provided at or near the axial end of the outer peripheral surface, so that the crushing allowance of the outer step portion with respect to the peripheral surface is reduced. In addition to being set, an inner peripheral projection is provided at or near an axial end portion of the inner peripheral surface, and a crushing allowance for the peripheral surface of the inner step portion is set. By setting the margin, an initial close contact with the mounting member is realized. Therefore, by realizing this initial close state,
The sealing performance in a low pressure state can be ensured. In addition, when the atmospheric condition becomes high pressure, the sealing portion having a single mountain cross section provided on the axial end surface of the packing comes into close contact with the end surface of the outer step portion or the inner step portion, so that the sealing member is weighted tightly to the mounting member. The state is realized. Therefore, by realizing the weighted close contact state, it is possible to ensure the sealing performance in the high pressure state. Therefore, it is possible to provide a packing that exhibits a sealing property not only in a high pressure state but also in a low pressure state, and also exhibits a sealing property according to the magnitude of the working pressure.

In addition, in the packing according to the first aspect of the present invention having the above structure, the packing is stably held by the mounting member by setting the crushing allowance by the formation of the projections. It is possible to set the axial length of the packing shorter than before, and it is only necessary to provide one seal portion on the axial end face of the packing in order to realize the above-mentioned weighted close contact state. A relatively large unfilled space is formed on the inner and outer circumferences. Therefore, the packing ratio of the packing in the mounting space can be reduced, and the packing ratio of the packing in the space (annular space) in which the packing is mounted can be suppressed to 100% or less, so that the packing protrudes from the mounting space. Damage can be prevented beforehand.

Further, the present invention has the above-mentioned structure.
In the packing according to the present invention, an outer peripheral projection is provided at or near an axial end portion of the outer peripheral surface of the packing so as to abut against the inner peripheral surface of the housing, and the outer diameter of the outer peripheral projection is larger than the inner diameter of the inner peripheral surface of the housing. The outer diameter of the outer peripheral surface of the packing is formed smaller than the inner diameter of the inner peripheral surface of the housing, and the inner peripheral surface of the inner peripheral surface of the packing is in contact with the outer peripheral surface of the injector at or near an axial end portion. A projection is provided, the inner diameter of the inner projection is formed smaller than the outer diameter of the outer peripheral surface of the injector, and the inner diameter of the inner peripheral surface of the packing is formed larger than the outer diameter of the outer peripheral surface of the injector. By setting the crushing allowance by forming these projections, an initial close contact with the mounting member is realized. Therefore,
By realizing the initial close contact state, it is possible to ensure the sealing performance in the low pressure state. Further, when the atmospheric condition becomes high pressure, the seal portions having one cross section provided on both end surfaces in the axial direction of the packing come into close contact with the first axial orthogonal surface and the second axial orthogonal surface, respectively. Thus, a weighted close contact with the mounting member is realized. Therefore, by realizing the weighted close contact state, it is possible to ensure the sealing performance in the high pressure state. Therefore, it is possible to provide a packing that exhibits sealing properties not only in a high pressure state but also in a low pressure state, and that exhibits sealing properties in accordance with the magnitude of the working pressure.

Further, in the packing according to the second aspect of the present invention having the above structure, the packing is stably held by the mounting member by setting the crushing allowance by the formation of the projection. It is possible to set the axial length of the seal shorter than before, and it is sufficient to provide a seal portion on each end surface in the axial direction of the packing in order to realize the above-mentioned weighted close contact state,
A relatively large unfilled space is formed on the inner and outer circumferences of the seal portion. Therefore, the filling rate of the packing in the mounting space can be reduced, and the filling rate of the packing in the space (annular space) where the packing is mounted can be suppressed to 100% or less.
Therefore, it is possible to prevent the packing from protruding from the mounting space and being damaged.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a packing according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a mounted state of the packing.

FIG. 3 is a sectional view showing a mounted state of a packing according to a comparative example.

4A and 4B are cross-sectional views of a packing according to a comparative example.

FIG. 5 is a sectional view showing a mounted state of a packing according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packing 2 Packing main-body part 2a Outer peripheral surface 2b Inner peripheral surface 2c Axial end surface 3 Outer peripheral protrusion (outer peripheral protrusion) 4 Inner peripheral protrusion (inner peripheral protrusion) 5 Seal part 6 Unfilled space 7 Depression 52 Housing (one member) 53) Insertion hole 54 Outer step (second step) 54a Peripheral surface (inner peripheral surface) 54b End surface (second axial orthogonal surface) 55 Injector (the other member) 56 Inner step (first step) Part) 56a peripheral surface (outer peripheral surface) 56b end surface (first axially orthogonal surface) 57 mounting space (vacant space)

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[Procedure amendment]

[Submission date] May 28, 2001 (2001.5.2)
8)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

FIG. 2

FIG. 3

FIG. 4

FIG. 5

Claims (2)

[Claims] An outer step (54) provided on one member (52) of the two members (52) and (55), and the other member (55) facing the outer step (54). ) Packing (1) interposed between the inner step (56) and
In the above, an outer peripheral projection (3) is provided at or near an axial end of an outer peripheral surface (2a) of the packing (1), and the outer peripheral projection (3) is provided on the outer peripheral surface (54) of the outer step (54). 54a)
The packing (1) has an inner peripheral projection (4) at or near the axial end of the inner peripheral surface (2b) of the packing (1), The protrusion (4) is provided on the peripheral surface (56a) of the inner step (56).
The packing (1) further comprises a sealing portion (5) having a single cross section on the axial end surface (2c) of the packing (1). Packing. 2. An outer peripheral surface (56) of an injector (55).
a) and a first extending radially outward from the outer peripheral surface (56a).
Of the first step portion (5)
6) and a second stepped portion (54) comprising an inner peripheral surface (54a) of the housing (52) and a second axially orthogonal surface (54b) extending radially inward from the inner peripheral surface (54a). ), Which is disposed in an annular space (57) and seals between the housing (52) and the injector (55), and an outer peripheral surface (2a) of the packing (1). The outer peripheral projection (3) contacting the inner peripheral surface (54a) at or near the axial end of the packing, and the axial end at or near the inner peripheral surface (2b) of the packing (1), An inner peripheral projection (4) that comes into contact with an outer peripheral surface (56a) is provided. Both end surfaces (2c) of the packing (1) in the axial direction are provided with a first axial orthogonal surface (56b) and a second axial direction. It has a sealing portion (5) having a single cross section which is in contact with the orthogonal surface (54b). The outer diameter of the outer projection (3) is larger than the inner diameter of the inner surface (54a) of the housing (52), and the outer diameter of the outer surface (2a) of the packing (1) is larger than the inner surface (54a). ), The inner diameter of the inner peripheral projection (4) is smaller than the outer diameter of the outer peripheral surface (56a) of the injector (55), and the inner peripheral surface (2b) of the packing (1) is smaller. A packing characterized in that the inner diameter is larger than the outer diameter of the outer peripheral surface (56a).