JP2566525B2 - Gasket for plug-in flange - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mainly used for inserting and interposing between an inner pipe and an outer pipe which form a joint portion of an exhaust pipe of an automobile or a two-wheeled vehicle so as to exhibit sealing performance such as leakage prevention of exhaust gas. The present invention relates to a gasket for an insert flange.

[0002]

2. Description of the Related Art As shown in FIG. 8, a tape-shaped metal mesh material 20 formed by knitting a metal wire typified by a stainless wire has been used as a gasket for an insertion flange of this type. 9 is impregnated with a powder of an inorganic material 21 such as expanded graphite, which is then wound into, for example, a spiral shape to form a predetermined ring shape.
As shown in FIG. 1, it is known that an expanded graphite sheet 22 and a metal mesh material 23 in which a metal wire such as a stainless wire is knit-knitted are integrally formed into a predetermined ring shape.

As shown in FIG. 10, the conventional insertion flange gasket G having the above-mentioned structure is inserted into the outer peripheral surface of the inner pipe 25 constituting the joint portion 24 of the exhaust pipe from the axial direction thereof, and then the The outer tube 26 constituting the joint portion 24 is inserted into the outer peripheral surface of the gasket G from the axial direction thereof,
By fixing the inner and outer tubes 25, 26 via a clamp 27 wound around the outer tube 26, the inner and outer tubes 25,
It is used by being interposed between the outer and inner peripheral surfaces of 26 facing each other. In the conventional gasket thus inserted and used, the inner diameter D1 is substantially equal to the outer diameter of the inner pipe 25, and the outer diameter D2 is equal to the inner diameter of the outer pipe 26 in order to secure the sealing property at the initial insertion. It was general that they were configured to have substantially equal diameter dimensions.

[0004]

Since the conventional insertion flange gasket as described above has the above-described diameter dimension, the gasket G and the inner and outer pipes 2 are formed.
Depending on the finished dimensions of 5, 26, the resistance when inserting into the inner tube 25 and the outer tube against the gasket G is large, not only a great deal of effort is required for centering, but also a large inserting operation force (pushing force). Force), and the gasket G may be destroyed when it is inserted. In addition, the inner tube 25 or the outer tube 2 is attached to the gasket G.
When inserting 6, the inner and outer peripheral surfaces and the corners of the gasket G are easily damaged, so that there is a problem that a stable sealing property cannot be obtained at the time of initial insertion.

[0005] The present invention has been made in view of the above circumstances, together with insertion work of insertion and the outer tube to the inner tube
The resistance less with easily, to prevent damage to the main seal surface on the insertion time, and its object is to provide a bayonet flange gasket can be ensured a stable sealing property from time of initial insertion.

[0006]

In order to achieve the above object, a gasket for an insert flange according to the present invention is for an insert flange formed by integrally molding an inorganic material and a metal mesh material to form a ring-shaped base. In the gasket,
Insert flanges on both end faces of the ring-shaped base in the axial direction.
The taper part is formed in the insertion direction of
In addition , at least one annular projection protruding radially outward is integrally formed on at least the outer peripheral surface of the inner and outer peripheral surfaces of the ring-shaped base .

In the gasket for plug-in flange having the above construction, the inorganic material is selected from expanded graphite sheet, mica sheet, ceramic fiber mixed paper and vermiculite mixed paper, and the metal mesh material is metal. It is preferable to use a wire knitted.

Further, in the gasket for insert flange having the above construction, it is preferable that the annular projection is integrally formed on the inner peripheral surface and the outer peripheral surface of the ring-shaped base body by axially displacing each other.

Further, in the gasket for insert flange having the above construction, it is desirable that the metal mesh material constituting the ring-shaped base body is arranged at an intermediate portion in the axial direction of the base body.

[0010]

According to the present invention, both of the ring-shaped substrate in the axial direction are
A taper is formed on the end face in the insertion direction of the insertion flange.
Since it is formed, the gasket constitutes the joint portion.
When inserting from the axial direction into the outer peripheral surface of the inner pipe, one taper
The part serves as an insertion guide, and there is little resistance and the difference is smooth.
Together with put one end corner of the axial direction of the ring-shaped body
Can be prevented from colliding with the inner pipe and being damaged
It is. In addition, at least the outer peripheral surface of the ring-shaped substrate
Has a ring-shaped projection that projects outward in the radial direction, so it can be inserted into the outer peripheral surface of the inner pipe that constitutes the joint.
Even when the outer pipe forming the joint portion is inserted into the outer peripheral surface of the retained gasket from the axial direction , the end portion of the outer pipe is
Damage to the other part by colliding with the other corner of the axial direction of the base
Without doing so, only the annular projection comes into contact with the inner peripheral surface of the outer tube, and precise centering is unnecessary, and
You can insert it smoothly with less resistance and perform the prescribed insertion work.
Smooth and easy. Moreover, even if the outer tube is inserted with a slight inclination, the outer peripheral surface and the corners of the ring-shaped base body will not be damaged, and the annular projection that elastically displaces radially inward when inserted will Is elastically strongly contacted with the inner peripheral surface of the outer tube to exert a secondary sealing function, and the inner peripheral surface portion of the ring-shaped base body where the annular protrusion is formed is also deformed inward in the radial direction. Since it comes into contact with the outer peripheral surface of the inner pipe, it is possible to secure a stable sealing property from the initial insertion.

If the annular projections are formed integrally on the inner and outer peripheral surfaces of the ring-shaped base body by axially displacing each other, the gasket can be inserted into the outer peripheral surface of the inner pipe.
Similarly to the above, since the contact area is small, the resistance can be reduced and the insertion can be easily performed, and the sealing property between the insertion tube and the inner tube can be further improved.

Further, when the metal mesh material is arranged at the intermediate portion in the axial direction of the ring-shaped substrate, the handling rigidity of the ring-shaped substrate is improved and the removability after use is improved. Can be achieved.

The amount of protrusion of the annular projection on the gasket is 0.8 of the inner diameter of the outer pipe of the insertion flange so that the gasket can be manually mounted.
%, And 0.05% of the inner diameter of the outer tube of the insertion flange in order to function as a secondary seal.
It is preferable to make the above.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a gasket for a plug-in flange according to an embodiment of the present invention in a state where its axial center portion is half-divided.

In FIG. 1, 1 is a band-shaped expanded graphite sheet having a thickness of 0.38 mm (an example of an inorganic material), and 2 is a knitted knitted stainless wire (an example of a metal wire) having a diameter of 0.22 mm. The expanded graphite sheet 1 and the metallic mesh material 2 are formed of the expanded graphite sheet 1 between the inner and outer fixed molds 3 and 4 as shown in FIG. With the metal mesh material 2 wrapped around it, the pair of inner and outer fixed molds 3 and 4 are inserted.
By press molding such as pushing the movable mold 5 in between,
The ring-shaped base 6 is manufactured.

Reference numeral 7 denotes an outer peripheral surface of the ring-shaped base 6, which is an annular protrusion made of expanded graphite which projects radially outward from a substantially central portion in the axial direction thereof.
At the time of press molding as shown in (1), it is integrally formed by the concave portion 4a formed in the outer fixed mold 4. Further, taper portions 6a and 6b are formed on both end surfaces of the ring-shaped base 6 in the axial direction toward the insertion direction of the insertion flange, and the inner diameter D of the ring-shaped base 6 is further formed.
11 is set to be slightly larger than the outer diameter of the inner pipe forming the joint portion of the exhaust pipe, and the outer diameter D12 of the ring-shaped base 6 is larger than the inner diameter of the outer pipe forming the joint portion of the exhaust pipe. The diameter D13 including the outer top portion of the annular projection 7 is set to be slightly smaller than the inner diameter of the outer pipe forming the joint portion of the exhaust pipe.

As shown in FIG. 4, the plug-in flange gasket G having the above-described structure has a joint portion 2 of the exhaust pipe.
4 is inserted into the outer peripheral surface of the inner pipe 25 from the axial direction thereof. Thus, the plug itself, together with enabling the resistance less smoothly, when insertion of the gasket G, the ring-shaped substrate by the presence of the tapered portions 6a formed on one end face in the axial direction of the ring-shaped substrate 6 6
It is possible to prevent the one end corner portion in the axial direction of the device from being damaged.

Next, as shown in FIG. 5, the outer pipe 26 constituting the joint portion 24 is inserted in the axial direction from the outer peripheral surface of the gasket G inserted and held in the outer peripheral surface of the inner pipe 25. At this time, too, the end of the outer tube 26 is
The other end of the ring-shaped base 6 in the axial direction is collided and the portion
Since the annular projection 7 only comes into contact with the inner peripheral surface of the outer tube 26 without being damaged, even if the outer tube 26 is inserted with a slight inclination, the outer peripheral surface of the ring-shaped base 6 and the main seal surface are The taper portions 6a and 6b, which become the above, are not damaged. Further, when the outer pipe 26 is inserted, the annular projection 7 is elastically displaced inward in the radial direction, but after the insertion, as shown in FIG. The outer top portion of the protrusion 7 elastically and strongly abuts the inner peripheral surface of the outer tube 26 to form a secondary seal portion. Therefore, the tapered portions 6 at both ends in the axial direction of the ring-shaped base 6
The main sealing surface composed of a and 6b is formed by the main sealing portion formed by elastically contacting the inner surface of the stepped portion 26a of the outer tube 26 and the outer surface of the stepped portion 25a of the inner tube 25, respectively, and the annular projection 7. With the secondary sealing portion on the inner and outer peripheral surfaces of the gasket G, the stable sealing property can be secured even after the initial insertion.

After a predetermined insertion, that is, after the assembly of the joint portion of the exhaust pipe is completed, the inner and outer pipes 25, 2 are clamped via a clamp 27 such as a belt wound around the outer peripheral portion of the outer pipe 26.
Although the joint portion is held in a detached state by fixing 6, the clamp 27 such as the belt does not need to be particularly strongly tightened in order to improve the sealing property.

FIG. 7 is a vertical cross-sectional view of a gasket G for a plug-in flange according to another embodiment of the present invention in a state where its axial center portion is half-divided. In this embodiment, the expansion of the above embodiment is used as an inorganic material. Instead of the graphite sheet, the thickness is 0.
A 4 mm mica sheet 1A is used, and two annular protrusions 7A and 7B are integrally formed on the outer peripheral surface and the inner peripheral surface of the ring-shaped substrate 6 by axially displacing each other.

In the insertion flange gasket G of the embodiment shown in FIG. 7, the inner top portion of the annular projection 7B formed on the inner peripheral surface of the ring-shaped base 6 elastically strongly abuts on the outer peripheral surface of the inner pipe 25. Since the secondary seal portion is formed as a result of this, the annular projection 7A on the outer peripheral surface side cooperates with the secondary seal portion formed between the outer peripheral surface side and the inner peripheral surface of the outer tube 26 to further improve the initial sealing. Not only can a stable sealing property be ensured, but also when the gasket G is inserted into the outer peripheral surface of the inner pipe 25, since the contact area is small, it is possible to easily insert it with reduced resistance.

In each of the above-mentioned embodiments, the metal mesh material 2 is arranged at the intermediate portion of the ring-shaped substrate 6 in the axial direction, but the invention is not particularly limited to this. You may interpose in the whole area of 6 of the axial direction.

In the following, as shown in the embodiment of FIG. 1, one annular projection 7 is integrally formed so as to project radially outward from a substantially central portion of the outer peripheral surface of the ring-shaped base 6 in the axial direction. , A gasket having tapered portions 6a and 6b formed on both end surfaces in the axial direction, a conventional product as shown in FIG. 8, and, as shown in FIG. 11, substantially the center of the outer peripheral surface of the ring-shaped base 6 in the axial direction. Gasket formed by integrally forming one annular projection 7 outwardly in the radial direction from the portion and eccentrically disposing the metal mesher material 2 on one end side in the axial direction of the ring-shaped base 6 (comparative example). The measurement results of the insertion resistance and the seal test in the above will be described.

The gasket in this embodiment has an inner diameter of 45.8 mm and a main outer diameter of 50.9 m.
m, the axial length is 20.3 mm, and the annular projection has a width of 3.3 mm and an outer diameter of 52.0 mm.
The conventional gasket is made of the same material as that of the embodiment, and has an inner diameter of 45.1 mm and an outer diameter of 51.1 m.
m, and the axial length is 13.5 mm, which is formed into a tubular shape. Furthermore, the gaskets of the comparative examples are made of the same material as the examples, and are set to the same dimensions as the examples.

Table 1 shows the measurement results of the insertion resistance in each of the above-mentioned examples, conventional products and comparative examples.
In Table 1, the maximum clearance is a case where the outer diameter of the inner tube of the insertion flange to be mounted is the minimum (45.0 mm) and the inner diameter of the outer tube is the maximum (51.5 mm), and the minimum clearance is , The outer diameter of the inner tube of the mounting flange to be mounted is maximum (45.5 mm), and the inner diameter of the outer tube is minimum (51.2 mm)
This is the case.

[0026]

[Table 1]

As is apparent from Table 1, in the conventional product, the insertion resistance may vary greatly with respect to the variation in the dimensions of the insertion flange, and the gasket may be broken. It was stable and the gasket did not break.

Table 2 shows the results of the seal test in the above-mentioned examples, conventional products and comparative examples in the state of being mounted on the insertion flange. The outer diameter of the inner pipe of the used insertion flange was 45.0 mm, and the inner diameter of the outer pipe was 51.5 m.
m, and 0.3 kgf / cm ² as a test fluid
Of compressed air was used.

[0029]

[Table 2]

As is apparent from Table 2, the sealability of the example was significantly improved as compared with the conventional product and the comparative example.

[0031]

As described above, according to the present invention, the ring
How to insert the flanges on both ends of the base body in the axial direction
Since the tapered portion is formed in the direction, the gasket
Of the inner tube forming the joint part and the outer surface of the inner tube
A joint is attached to the outer peripheral surface of the gasket inserted and retained in the inner pipe.
The axis of the ring-shaped substrate when inserting the outer tube
Both end corners in the direction of the inner pipe collide with the ends of the inner and outer pipes and are damaged.
Not only can you prevent it from plugging into the inner tube
At the time of inserting the outer pipe constituting the joint portion from the axial direction into the outer peripheral surface of the retained gasket, at least the ring-shaped base body is used.
Is also integrally formed on the outer peripheral surface so as to project radially outward
With only has an annular projection which is becomes into contact with the inner peripheral surface of the outer tube, it can be precise centering unnecessary, since the insertion resistance small, very circle a predetermined insertion work
It can be done easily. In addition, even if the outer tube is inserted with a slight inclination, it is possible to prevent the outer peripheral surface and corners of the ring-shaped base from being damaged, and insert the annular projection that elastically displaces radially inward when inserted. Then, elastically and strongly contact the inner surface of the outer tube and the outer surface of the inner tube.
Since the next sealing function can be exerted, there is an effect that a stable sealing property can be secured from the initial insertion.

When the annular projections are integrally formed on the inner and outer peripheral surfaces of the ring-shaped base body by axially displacing each other, as in claim 3, in addition to the above-mentioned effect, the gasket is formed on the inner pipe. Also when inserting into the outer peripheral surface, the insertion resistance can be reduced in the same manner as described above to facilitate the predetermined insertion work, and also to improve the sealing property with the inner tube after insertion.

Further, when the metal mesh material is arranged at the intermediate portion of the ring-shaped substrate in the axial direction as in claim 4, in addition to the above effects, the handling rigidity of the gasket is improved. Not only can it be improved, but also the removability after use can be improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a gasket for a plug-in flange according to an embodiment of the present invention in a half-cut state.

FIG. 2 is a schematic cross-sectional view showing a molded state of the gasket in the above-mentioned embodiment.

FIG. 3 is a schematic perspective view showing a state of an expanded graphite sheet and a metal mesh material before forming a gasket in the same example.

FIG. 4 is a vertical cross-sectional view of a main part showing a state in which the gasket according to the above embodiment is inserted into the outer peripheral surface of the inner pipe that constitutes the joint portion of the exhaust pipe.

FIG. 5 is a longitudinal cross-sectional view of a main part showing a state in which an outer pipe forming a joint portion of an exhaust pipe is inserted into an outer peripheral surface of a gasket according to the above embodiment.

FIG. 6 is a vertical cross-sectional view of a main part showing a completed mounting state of the gasket in the above embodiment.

FIG. 7 is a vertical cross-sectional view showing a gasket for plug-in flange according to another embodiment of the present invention in a half-cut state.

FIG. 8 is a vertical cross-sectional view showing an example of a conventional insertion flange gasket in a half-cut state.

FIG. 9 is a vertical cross-sectional view showing another example of a conventional insertion flange gasket in a half-cut state.

FIG. 10 is a vertical cross-sectional view of a main part showing a state in which mounting of a conventional gasket is completed.

FIG. 11 is a vertical cross-sectional view showing a gasket of a comparative example subjected to insertion resistance and seal tests in a half-cut state.

[Explanation of symbols]

1 Expanded graphite sheet (an example of an inorganic material) 1A Mica sheet (another example of an inorganic material) 2 Metal mesh material 6 Ring-shaped bases 6a, 6b Tapered parts 7, 7A, 7B Annular protrusion

Claims (4)

(57) [Claims] 1. A gasket for a plug-in flange, which comprises an inorganic material and a metal mesh material integrally molded to form a ring-shaped base , wherein both ends of the ring-shaped base in the axial direction.
The taper is shaped to face the insertion direction of the flange.
A gasket for a plug-in flange, which is formed, and at least one annular projection protruding outward in the radial direction is integrally formed on at least the outer peripheral surface of the inner and outer peripheral surfaces of the ring-shaped base body . 2. The inorganic material is selected from an expanded graphite sheet, a mica sheet, a ceramic fiber mixed paper product and a vermiculite mixed paper product, and the metal mesh material is formed by knitting a metal wire. The insert flange gasket according to claim 1. 3. The gasket for plug-in flange according to claim 1, wherein the annular projection is integrally formed on the inner peripheral surface and the outer peripheral surface of the ring-shaped base body by axially displacing each other. 4. The gasket for insert flange according to claim 1, wherein the metal mesh material forming the ring-shaped base is arranged at an intermediate portion in the axial direction of the base.