JP3275531B2 - Exhaust pipe joint and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust pipe joint used for automobiles, motorcycles and the like.

[0002]

2. Description of the Related Art As an exhaust pipe joint of this type, the present applicant has
In Japanese Utility Model Application Laid-Open No. 3-88552 (Japanese Utility Model Application Laid-Open No. 5-32718), a cylindrical gasket disposed in the space between the enlarged cylindrical portion of the outer tube and the outer surface of the inner tube is pressed along the tube axis by a pair of pressing pieces. And compressively deform, filling the space with a cylindrical gasket more densely, filling the gap existing at the time of assembly,
As a result, the exhaust gas is prevented from leaking immediately after the fitting to the exhaust pipe, and the outer pipe and the inner pipe are fixed to each other by tightening the pair of pressing pieces, and the outer pipe and the inner pipe are connected to each other. An exhaust pipe joint was proposed to prevent damage to the cylindrical gasket caused by vibration of the exhaust pipe.

[0003]

In the exhaust pipe joint according to the above proposal, the initial purpose of preventing leakage of exhaust gas immediately after the fitting to the exhaust pipe and preventing damage to the cylindrical gasket is preferable. Although it was confirmed that this could be achieved, in the specific example specified therein, the cylindrical gasket was compressed into the space between the enlarged cylindrical portion of the outer tube and the outer surface of the inner tube by moving the pressing piece by tightening a pair of bolts. Therefore, when the degree of tightening of the pair of bolts is different from each other, the degree of compressive deformation of the cylindrical gasket is different in the circumferential direction, and as a result, it is not possible to preferably achieve prevention of leakage of exhaust gas. It turned out that there was a fear. For this reason, when manufacturing and disassembling and assembling the exhaust pipe joint, mutual adjustment of the degree of tightening of the pair of bolts is required, and the workability is not so excellent. Further, in the specific example of the exhaust pipe joint proposed above, the mutual fixing between the outer pipe and the inner pipe by tightening the pair of pressing pieces is performed by tightening a pair of bolts further provided outside the above-described pair of bolts. Therefore, in the manufacture, disassembly and assembly thereof, it is necessary to tighten two pairs of bolts, and in this respect, the workability is not so excellent.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object the need for adjustment, the degree of compressive deformation of a cylindrical gasket can be made substantially the same in the circumferential direction, and An exhaust pipe joint which can preferably achieve gas leakage prevention, can prevent damage to a cylindrical gasket due to vibration of an outer pipe and an inner pipe, and has extremely excellent manufacturing, disassembling and assembling workability, and a method of manufacturing the same. To provide.

[0005]

SUMMARY OF THE INVENTION According to the present invention, there is provided an outer tube having an outer tube body, an outer tube having an enlarged end connected to the outer tube body via a shoulder, and an outer tube having an enlarged diameter. An inner tube having an end inserted into the radial end and an enlarged portion connected to the end via a shoulder and inserted into the enlarged end of the outer tube, and an outer periphery of the end of the inner tube A cylindrical gasket arranged in an annular space between the outer surface and the inner peripheral surface of the enlarged end of the outer tube, and pressing the cylindrical gasket along the pipe axis and toward the shoulder of the outer tube while holding the outer tube inside. A press fitting for fixing to a pipe, an exhaust pipe joint including fixing means, wherein the pressing and fixing means includes at least a pair of split grooves formed along the pipe axis at an enlarged end of the outer pipe. The outer tube side engaging portion provided at the enlarged end portion of the outer tube, and the inner tube side provided at the enlarged portion of the inner tube, extending outside the outer tube through each of the notch grooves. A stop portion, a band-shaped member having one end abutting on the locking portion on the outer tube side and the other end abutting on the locking portion on the inner tube side and arranged on the outer peripheral surface of the enlarged end portion of the outer tube; Tightening means provided at the end of the band-shaped member for tightening the band-shaped member to the enlarged end of the outer tube, wherein the cylindrical gasket is provided with a shoulder portion of the outer tube via the shoulder of the inner tube by the band-shaped member. The band-shaped member is elastically deformed by the tightening of the tightening means so that the length in the direction along the tube axis is elongated, and the enlarged-diameter end portion of the outer tube is connected to the band-shaped member. This is achieved by the exhaust pipe joint pressed and fixed to the enlarged diameter portion of the inner pipe by tightening.

According to the present invention, the object is to provide an outer tube main body, an enlarged end portion connected to the outer tube main body via a shoulder,
An outer tube having at least a pair of slits formed at the enlarged diameter end along the pipe axis and an engaging portion provided at the enlarged diameter end, and an end having a cylindrical gasket inserted therein. Part, an enlarged portion connected to the end portion via a shoulder portion, and an inner tube provided with an engaging portion provided on the enlarged portion, respectively, and an inner tube having a cylindrical gasket inserted therein is prepared. The end portion and the enlarged diameter portion of the inner pipe are connected to each other. It is arranged in the annular space between the inner peripheral surface of the radial end and inserted into the enlarged end of the outer tube, and is inserted between the outer tube side engaging portion and the inner tube side engaging portion. On the outer peripheral surface of the enlarged end portion of the outer tube, a band member elastically deformable in the tube axis direction is arranged, and the band member is tightened, and the band member is elastically deformed by the tightening. Extend one end of the band-shaped member to the outer tube side engaging portion so as to extend in the tube axis direction and press the cylindrical gasket toward the outer tube shoulder portion via the inner tube shoulder portion. This is achieved by a method of manufacturing an exhaust pipe joint in which an end is brought into contact with a locking portion on the inner pipe side, and the enlarged end of the outer pipe is pressed and fixed to the enlarged diameter section of the inner pipe via the band-shaped member by the tightening. Is done.

[0007] In the above exhaust pipe joint, one preferable example of the shape of the belt-shaped member before tightening is an arc-shaped cross section or a cross-sectional waveform. The cross section is particularly preferably arc-shaped, but the present invention is not limited to this.
Examples of the material of the belt-like member include steel, stainless steel, and a spring material. An ear having a through hole may be formed at each end of the band-shaped member, and the fastening means may be configured by a bolt disposed in the through hole of the ear and a nut screwed to the bolt. In this case, if the bolt can be rotated from a direction perpendicular to the tube axis, the workability of manufacturing, disassembling and assembling is further improved. Further, in the case where the shape of the belt-shaped member before fastening is an arc-shaped cross section, for example, the vicinity of the end of the belt-shaped member is formed so that its width becomes narrower toward the ear portion, and the belt-shaped member is securely tightened. You may do so.

Normally, the outer pipe constituting the exhaust pipe of the exhaust pipe joint is fixedly connected to the muffler side, and the inner pipe forming the exhaust pipe connected to the outer pipe is connected to the engine side. It is not limited to. As a cylindrical gasket,
The material is not particularly limited as long as it is easily deformed when compressed and has a heat resistance.For example, a reinforcing material made of a wire mesh obtained by weaving or knitting a thin metal wire such as stainless steel, and an expansion material A preferred example is obtained by laminating a heat-resistant sheet such as graphite or mica, winding this into a cylindrical shape to form a preform, and compressing the preform in the axial direction. be able to.

[0009]

As described above, the exhaust pipe joint of the present invention is generally used by connecting the outer pipe to the muffler side and the inner pipe to the engine side. Since the cylindrical gasket disposed in the annular space between the outer peripheral surface of the end of the inner tube and the inner peripheral surface of the enlarged end of the outer tube is pressed and compressed in the annular space by the band-shaped member, The annular space is tightly filled by the cylindrical gasket, so that leakage of exhaust gas can be prevented immediately after assembly. Then, the band member is elastically deformed by the tightening of the tightening means, and the cylindrical gasket is pressed and compressed in the annular space, so that the cylindrical gasket is uniformly pressed and compressed in the annular space. Further, since the enlarged end of the outer tube is pressed and fixed to the enlarged portion of the inner tube by tightening the belt-shaped member, relative vibration is less likely to occur between the outer tube and the inner tube. Damage to the cylindrical gasket due to vibration between the inner gasket and the inner tube is prevented.

Next, the present invention will be described in more detail with reference to a preferred embodiment shown in the drawings. The present invention is not limited to these specific examples.

[0011]

1 to 4 show an exhaust pipe joint 1 of this embodiment.
Is an outer tube 5 having an outer tube main body 2 and an enlarged diameter end 4 connected to the outer tube main body 2 via a shoulder 3, and an end 6 inserted into the enlarged diameter end 4 of the outer tube 5. And an inner tube 11 having an enlarged diameter portion 10 connected to the end portion 6 via a shoulder portion 9 and inserted into the enlarged diameter end portion 4 of the outer tube 5, and an outer peripheral surface 12 of the end portion 6 of the inner tube 11. A cylindrical gasket 15 disposed in an annular space 14 between the inner peripheral surface 13 of the outer tube 5 and the inner peripheral surface 13 of the outer tube 5, and the cylindrical gasket 15 is directed along the pipe axis A and toward the shoulder 3 of the outer tube 5. And a pressing and fixing means 16 for pressing and fixing the outer tube 5 to the inner tube 11.

The inner tube 11 of this embodiment comprises an inner tube main body 21 having a small diameter, the aforementioned end portion 6 and the enlarged diameter portion 10, and the inner tube main body 21 and the end portion 6 are formed to have the same diameter. In addition, the inner pipe main body 21 does not need to be the same diameter as the end part 6 like this example,
For example, it may be formed to have the same diameter as the enlarged diameter portion 10. The inner pipe main body 21 and the enlarged diameter portion 10 are connected via a shoulder 22.

The pressing and fixing means 16 includes a pair of split grooves 31 and 3 formed on the enlarged diameter end 4 so as to extend along the tube axis A.
2, an enlarged end 33 provided at the enlarged end 4 as a locking portion on the outer tube 5 side, and an inner tube extending outside the outer tube 5 through each of the pair of cut grooves 31 and 32. A pair of inverted L-shaped fittings 34 as locking portions on the side of the inner pipe 11 provided by being fixed to the enlarged diameter portion 10 by welding, one end 35 abuts the base of the enlarged diameter end 33, and the other end 36. Are provided on an end portion 38 of the band-shaped member 37 for contacting the inverted L-shaped bracket 34 and disposed on the outer peripheral surface of the enlarged-diameter end portion 4 and for fastening the band-shaped member 37 to the enlarged-diameter end portion 4. And fastening means 39.

Although the two split grooves 31 and 32 in this embodiment are formed symmetrically with respect to the tube axis A, two or more split grooves 31 and 32 may be provided, for example, three. In this case, although not particularly limited, 120
It is preferable to provide them at equal angular intervals, and in this case, it is preferable to provide the inverted L-shaped bracket 34 correspondingly. The engaging portion on the outer tube 5 side may be embodied by an enlarged end 33 formed by enlarging the distal end of the enlarged end 4 as in this example.
Instead of this, for example, a flange member or a fitting equivalent to the inverted L-shaped fitting 34 is integrally formed or fixed to the end of the enlarged diameter end 4 by welding or the like to realize the locking portion on the outer tube 5 side. You may.

The belt-like member 37 includes a belt main body 51 and a band main body 5.
A pair of opposed ears 52 and 5 integrally formed at one end and bent outward with respect to the band body 51.
And the ears 52 and 53 have through holes 54.
And 55 are formed. The band main body 51 is formed so that its width becomes narrower toward the ears 52 and 53 near its end.

The fastening means 39 of this embodiment includes a bolt 56 inserted through the through holes 54 and 55 and a nut 57 screwed to the bolt 56. With the diameter of the band main body 51 reduced, the band main body 51 is fastened to the outer peripheral surface of the enlarged diameter end portion 4.

The cylindrical gasket 15 is pressed by the band body 51 through the shoulder 9 toward the shoulder 3 of the outer tube 5, and the length of the band body 51 in the direction along the tube axis A is increased. As a result, it is elastically deformed by the tightening of the tightening means 39. FIG. 6 shows the shape of the belt body 51 of the present embodiment before tightening.
As shown in FIG. 1, the band main body 51 having such a cross-sectional shape is elastically deformed into a flat plate-shaped cross-section as shown in FIG. The enlarged diameter end portion 4 of the outer tube 5 is pressed and fixed to the outer peripheral surface of the enlarged diameter portion 10 of the inner tube 11 by tightening the tightening means 39.

The exhaust pipe joint 1 constructed as described above is assembled and manufactured as follows. That is, as shown in FIG. 6, first, the outer tube main body 2, the enlarged diameter end 4 connected to the outer tube main body 2 via the shoulder 3, and the extended diameter end 4 formed along the tube axis A. Outer tube 5 having a pair of cut grooves 31 and 32 and an enlarged end 33 provided at the enlarged end 4.
End portion 6 into which cylindrical gasket 15 is press-fitted and inserted, enlarged diameter portion 10 and enlarged diameter portion 1 connected to end portion 6 via shoulder 9.
0, a pair of inverted L-shaped fittings 3 secured by welding
4 are prepared.

Next, the end 6 with the cylindrical gasket 15 inserted therein and the enlarged diameter portion 10 are separated from each other by a pair of inverted L-shaped fittings 34 through the pair of slits 31 and 32, respectively. And the cylindrical gasket 15 is disposed in the annular space 14 between the outer peripheral surface 12 of the end 6 and the inner peripheral surface 13 of the enlarged end 4 so as to be inserted into the enlarged end 4 and expanded. A band-like member 37 elastically deformable in the direction of the tube axis A is disposed between the radial end 33 and the inverted L-shaped bracket 34 on the outer peripheral surface of the enlarged diameter end 4, and a bolt 56 is screwed into a nut 57 and tightened. As a result, the band-shaped member 37 is tightened, and the band main body 51 is elastically deformed by this tightening to extend in the direction of the tube axis A, so that the cylindrical gasket 15 is pressed toward the shoulder 3 via the shoulder 9. Body 5
One end 35 of the outer tube 5 is brought into contact with the base of the enlarged diameter end 33, the other end 36 is brought into contact with the L-shaped bracket 34, and the enlarged diameter end 4 of the outer tube 5 is reduced by the contraction of the band body 51 by the tightening. The diameter is reduced and this is pressed and fixed to the outer peripheral surface of the enlarged diameter portion 10.

In the exhaust pipe joint 1 of the present embodiment shown in FIG. 1 assembled and manufactured as described above, the cylindrical gasket 15 is pressed tightly against the outer peripheral surface 12 and the inner peripheral surface 13 to densely fill the annular space 14. Therefore, leakage of exhaust gas from the annular space 14 can be prevented as desired.

In the exhaust pipe joint 1, the belt-like member 37 is elastically deformed by tightening the bolt 56, whereby the enlarged diameter end 33 and the inverted L-shaped bracket 34 are separated from each other along the pipe axis A, and the shoulder portion is formed. 9, press the cylindrical gasket 15
Because of the compression deformation, the degree of compression deformation of the cylindrical gasket 15 can be made substantially the same in the circumferential direction without adjusting the degree of tightening of the bolt 56. In other words, in the exhaust pipe joint 1 of the present embodiment, it is necessary to adjust the degree of tightening of the bolt 56 in order to cause the cylindrical gasket 15 to undergo a compression deformation of a predetermined amount or more. To make the degree substantially the same in the circumferential direction, the tightening adjustment of the bolt 56 may not be necessary.

In the exhaust pipe joint 1, the enlarged diameter end 4 is pressed against and fixed to the outer peripheral surface of the enlarged diameter portion 10, and the outer pipe 5 is connected to the inner pipe 11.
, The relative mutual vibration of the outer tube 5 and the inner tube 11 can be eliminated, and the cylindrical gasket 15 can be prevented from being deteriorated by the minute vibration of the shoulder portion 9.

In the above description, the band-shaped member 3 having an arc-shaped cross section is used.
Although the elastic member 7 is elastically deformed, the exhaust pipe joint 72 according to the present invention may be formed by elastically deforming the band-like member 71 having a sectional waveform as shown in FIG. Although the cross-sectional waveform of the illustrated band-shaped member 71 has two peaks, one or three or more peaks may be used.

[0024]

As described above, according to the present invention, no adjustment is required, the degree of compressive deformation of the cylindrical gasket can be made substantially the same in the circumferential direction, and leakage of exhaust gas can be preferably achieved. In addition, it is possible to prevent the cylindrical gasket from being damaged due to the vibration between the outer pipe and the inner pipe, and to provide an exhaust pipe joint having extremely excellent workability in manufacturing, disassembling and assembling.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one preferred embodiment of the present invention.

FIG. 2 is a left side view of the outer tube shown in FIG.

FIG. 3 is a left side view of the inner tube shown in FIG. 1;

FIG. 4 is a side view of the band-shaped member and the fastening means shown in FIG.

FIG. 5 is a front view of the band-shaped member and the fastening means shown in FIG. 4;

FIG. 6 is an explanatory view of an assembling / manufacturing method of the specific example shown in FIG. 1;

FIG. 7 is a sectional view showing another example of the belt-shaped member according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 exhaust pipe joint 5 outer pipe 11 inner pipe 15 cylindrical gasket 16 pressing and fixing means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F01N 7/08

Claims (8)

(57) [Claims] 1. An outer tube having an outer tube main body and an enlarged end connected to the outer tube main body via a shoulder, an end inserted into the enlarged end of the outer tube, and this end. An inner pipe having an enlarged diameter portion which is connected to the enlarged diameter end of the outer pipe through a shoulder, and an outer peripheral surface of an end of the inner pipe and an inner peripheral surface of the enlarged diameter end of the outer pipe. Exhaust gas provided with a cylindrical gasket disposed in an annular space between the cylindrical gasket and a pressing and fixing means for pressing the cylindrical gasket along the pipe axis and toward the shoulder of the outer pipe and fixing the outer pipe to the inner pipe. A pipe joint, wherein the pressing and fixing means includes at least one pair of cut grooves formed along the pipe axis at the enlarged diameter end of the outer pipe, and an outer groove provided at the enlarged diameter end of the outer pipe. A tube-side locking portion, an inner-tube-side locking portion that extends outside the outer tube through each of the cut grooves and is provided at an enlarged-diameter portion of the inner tube, and one end of which is an outer-tube-side locking portion. Abuts the other A band-shaped member having an end abutting on the locking portion on the inner tube side and disposed on the outer peripheral surface of the enlarged end of the outer tube; and an end of the band-shaped member for fastening the band-shaped member to the enlarged end of the outer tube. The cylindrical gasket is pressed by the band-shaped member through the shoulder of the inner tube toward the shoulder of the outer tube, and the band-shaped member is oriented along the tube axis. The expanded end of the outer tube is pressed and fixed to the expanded portion of the inner tube by tightening the band-shaped member, so that the length of the outer tube is elongated so that the length of the outer tube is elongated .
The shape of the belt-shaped member before the beam is arc-shaped or corrugated in cross section.
The cylindrical gasket is woven from a thin metal wire such as stainless steel.
Reinforcement made of wire mesh obtained by knitting or knitting
Overlay a heat-resistant sheet such as Zhang graphite, mica, etc.
A preform formed by winding into a cylinder was compressed in the axial direction
Exhaust pipe joint is intended. 2. The shape of the belt-like member before tightening is two or more.
The exhaust pipe joint according to claim 1, wherein the peak has a cross-sectional waveform. 3. An end portion having a through hole is formed at each end of the band-shaped member, and the fastening means is screwed to the bolt disposed in the through hole of the ear portion. The exhaust pipe joint according to claim 1, further comprising a nut. 4. The exhaust pipe joint according to claim 3, wherein the width of the vicinity of the end of the band-shaped member decreases toward the ear. 5. An outer tube main body, an enlarged end connected to the outer tube main via a shoulder, at least one pair of cut grooves formed at the enlarged end along the tube axis, and An outer pipe having a locking portion provided at the enlarged diameter end, an end at which the cylindrical gasket is inserted, an enlarged diameter portion connected to this end via a shoulder, and an enlarged diameter portion. An inner tube provided with each of the provided locking portions is prepared, and an end portion of the inner tube in which the cylindrical gasket is inserted and the enlarged diameter portion of the inner tube are provided. And the cylindrical gasket is disposed in the annular space between the outer peripheral surface of the end of the inner tube and the inner peripheral surface of the enlarged end of the outer tube through each of the outer tubes. A belt-like member that is elastically deformable in the tube axis direction on the outer peripheral surface of the enlarged end portion of the outer tube between the engagement portion on the outer tube side and the engagement portion on the inner tube side. Distribute Then, the band-shaped member is tightened, and the band-shaped member is elastically deformed by this tightening to extend in the tube axis direction, so that the cylindrical gasket is pressed toward the shoulder of the outer tube via the shoulder of the inner tube, One end of the band-shaped member is brought into contact with the locking portion on the outer tube side, and the other end is brought into contact with the locking portion on the inner tube side, and the enlarged end of the outer tube is inserted through the band-shaped member by the tightening. A method of manufacturing an exhaust pipe joint to be pressed and fixed to an enlarged diameter portion of a pipe, wherein the shape of the band-shaped member before tightening is:
It has an arc-shaped cross section or a corrugated cross section.
Obtained by weaving or knitting a thin metal wire such as stainless steel
Reinforcement made of wire mesh and heat resistance of expanded graphite, mica, etc.
It is made by overlapping a sheet and winding it into a cylindrical shape
Exhaust pipe joint using axially compressed preform
Manufacturing method . 6. The shape of the belt-like member before tightening is two or more.
The method for manufacturing an exhaust pipe joint according to claim 5, wherein the peaks have a cross-sectional waveform. 7. The exhaust pipe joint according to claim 5, wherein ears having through holes are formed at each end of the band-shaped member, and the ears are brought closer to each other to fasten the band-shaped member. Manufacturing method. 8. The method of manufacturing an exhaust pipe joint according to claim 7, wherein the width of the vicinity of the end of the band-shaped member decreases toward the ear.