JPH0564595U - Exhaust pipe joint structure - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to an exhaust pipe joint structure for connecting vehicle exhaust pipes to each other, thereby reducing the thickness of the exhaust pipe by eliminating welding to the exhaust pipe which causes intergranular corrosion. It is an object of the present invention to provide an exhaust pipe joint structure that can be achieved and is excellent in strength. [Structure] Two exhaust pipes 37, 39 in which substantially bowl-shaped joints 41, 43 having openings facing outward are formed at the connection ends 37a, 39a, and the connection end 37a of the exhaust pipes 37, 39. ，
An annular seal member 47 is formed in a shape and size that fits in the inner peripheral surface of each of the joint portions 41 and 43, and is fitted in 39a.
It is composed of a cylindrical seal pressing member 49 fixed on the same axis as 7, 39, and a tightening band 51 fitted and arranged on the outer circumferences of both connecting end portions 37a, 39.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an exhaust pipe joint structure for connecting exhaust pipes of a vehicle.

[0002]

[Prior Art]

 Conventionally, as a joint structure for connecting exhaust pipes of a vehicle, for example, as shown in FIG. 7, a gasket is provided between flanges 5 and 7 welded to the outer periphery of each connecting end of two connecting exhaust pipes 1 and 3. 9, both flanges 5 and 7 are bolted together, or, as shown in FIG. 8, one of the exhaust pipes 11 and 13 to be connected is connected to one of the exhaust pipes 11 by increasing the diameter of the connecting end portion 11a. The diameter portion 15 is formed, the connection end portion 13a of the exhaust pipe 13 is fitted to the large diameter portion 15, and the outer circumference of this fitting portion is formed by the U-shaped bolt 17, the support 19, and the U-shaped bolt 17. It is widely known to use a tightening fitting 23 made up of a nut 21 that is screwed to the threaded portion 17a.

In Japanese Utility Model Laid-Open No. 61-54583, as shown in FIGS. 9 and 10, an exhaust pipe 27 having a spherical bulging end portion 25 and an outer periphery of the spherical bulging end portion 25 are disclosed. From an exhaust pipe 31 having a funnel-shaped flare end 29 covering a part of the surface, and a tightening band 35 having a step 33 in the middle of the circumference of the butted portion of both exhaust pipes 27, 31. An exhaust pipe joint structure is disclosed.

[0004]

[Problems to be solved by the device]

 Thus, the weight of vehicles has been reduced as one means for achieving low pollution and high fuel efficiency due to recent environmental and resource problems, and the exhaust pipe itself is also expected to be thinner in accordance with the trend. ..

However, in the joint structure shown in FIG. 7, it is difficult to reduce the thickness of the exhaust pipes 1, 3 because the flanges 5, 7 must be welded to the outer circumferences of the exhaust pipes 1, 3. However, there is a problem that cracking occurs due to intergranular corrosion due to welding.

Further, although the exhaust pipes 11 and 13 can be thinned in the conventional structure shown in FIG. 8, as a result of tightening with the fastening metal fittings 23, the respective connecting end portions 11a and 13a of the exhaust pipes 11 and 13 are deformed. As a result, the exhaust pipes 11 and 13 from which the fastening fittings 23 have been removed cannot be reused.

Further, in the joint structure shown in FIG. 9, since the exhaust pipe 27 is provided with the spherical bulging end portion 25 and the connecting portion of the exhaust pipes 27 and 31 is formed into a spherical shape, the structure shown in FIG. It has been pointed out that although the strength of the connecting portion is improved, the exhaust pipes 27 and 31 are similarly deformed when tightened with the tightening band 35.

The present invention has been devised in view of the above circumstances, and it is possible to reduce the thickness of the exhaust pipe by eliminating welding to the exhaust pipe, which is one of the causes of intergranular corrosion. It is intended to provide a joint structure of.

[0009]

[Means for Solving the Problems]

 In order to achieve such an object, an exhaust pipe joint structure according to the present invention includes two exhaust pipes each of which has a substantially bowl-shaped joint portion with an opening facing outward at each connection end, and an exhaust pipe. An annular metal seal member, which is fitted in both connecting ends of the pipe and has a shape and size that closely adheres to the inner peripheral surfaces of the joints, and both exhaust pipes are formed on the inner periphery of the seal member. It is composed of a cylindrical metal seal pressing member fixed on the same shaft, and a tightening band fitted and arranged on the outer circumferences of the both connecting end portions.

[0010]

[Action]

 According to the present invention, since the seal member closely adheres to the inner peripheral surfaces of both joints, the seal member ensures the sealability of the exhaust pipe connecting portion and the seal member is welded to the seal pressing member. Even if the exhaust pipes are connected by tightening the tightening band, the seal member does not spread and sticks to both joints to prevent its deformation.

Then, the seal pressing member allows the exhaust gas in the exhaust pipe to smoothly flow down.

[0012]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a first embodiment of a joint structure according to the present invention. In the figure, 37 and 39 are two exhaust pipes to be connected, and flaring is applied to the respective connecting end portions 37a and 39a. It has a conical shape. Each of the connecting end portions 37a, 39a is provided with a substantially bowl-shaped joint portion 41, 43 with the opening facing outward, and both joint portions 41, 43 are arranged so as to abut each other. In addition, an annular bead is provided at the connecting portion of the exhaust pipes 37 and 39.

As shown in FIGS. 1 and 2, a bead portion 45 is formed in the circumferential direction inside the connecting end portions 37a and 39a so as to be in close contact with the inner peripheral surfaces of the joint portions 41 and 43. The annular metal seal member 47 is fitted and arranged with the same size as the inner diameters of the exhaust pipes 37 and 39.

Further, as shown in FIGS. 1 and 3, a cylindrical metal for preventing generation of abnormal noise due to exhaust gas is provided inside the cylindrical portion 48 of the seal member 47 with the bead portion 45 interposed therebetween. A seal pressing member 49 made of aluminum is welded on the same axis as both the exhaust pipes 37 and 39.

That is, as described above, since the seal member 47 is provided with the bead portion 45 that projects outward, the inside of the exhaust pipes 37, 39 will be removed unless the seal pressing member 49 is attached. Part of the exhaust gas passing therethrough becomes a vortex in the bead portion 45, and abnormal noise is generated. Therefore, in this embodiment, the seal pressing member 49 is welded to the inner periphery of the seal member 47 to prevent the exhaust gas from flowing into the bead portion 45 and prevent the generation of abnormal noise. Further, as will be described later, by welding the seal pressing member 49 to the tubular portion 48 of the seal member 47 in this manner, deformation of the seal member 47 at the time of tightening the joint portions 41 and 43 is prevented. It has become.

Reference numeral 51 denotes a tightening band that is fitted and arranged on the outer peripheral surface side of both the joint portions 41 and 43 to tighten them. As shown in FIG. 3, the tightening band 51 has both joint portions 41 and 43. 41, 43 is composed of a pair of split tightening bands 51a, 51b formed in such a size that they are in close contact with the outer peripheral surface of the split tightening bands 51a, 51b, as shown in FIG. The joint portions 41 and 43 can be tightened by bolting the bolt tightening portions 53 respectively provided in the.

A bead portion 55, which is in close contact with the outer peripheral surfaces of the joint portions 41 and 43, is formed on each of the split fastening bands 51a and 51b along the longitudinal direction, and the side edge portions thereof are shown in FIG. As shown in FIG. 5, a reinforcing flange 57 is provided by being bent into a substantially L-shaped cross section. In addition, in FIG. 3, 59 is a tightening bolt, 61 is a nut, and 63 is a washer.

Since the joint structure according to the present embodiment is configured in this way, in order to connect both the exhaust pipes 37, 39, first, the seal member 47 having the seal pressing member 49 welded to the inner circumference thereof is used. After fitting and arranging the seal member 47 in the joint portion 41 of the one exhaust pipe 37, the seal member 47 is fitted in the other exhaust pipe 39 and the connecting end portions 37a and 39a are butted to each other to join the seal member 47 to the joint portion. The inner peripheral surfaces of 41 and 43 are closely attached. Next, the split tightening bands 51a and 51b are respectively fitted and arranged on the outer peripheral surface sides of the joints 41 and 43, and the bolt tightening portions 53 are bolted, whereby the joints 41 and 43 are joined together. Both exhaust pipes 37 and 39 are connected by being tightened with a tightening band 51.

By connecting the exhaust pipes 37 and 39 in this manner, the bead portion 45 of the seal member 47 is brought into close contact with the inner peripheral surfaces of both the joint portions 41 and 43, so that the exhaust gas is exhausted by the seal member 47. The sealing property of the connecting portion of the pipes 37 and 39 is secured. In addition, since the tubular portion 48 of the seal member 47 is welded to the seal pressing member 49 with the bead portion 45 interposed therebetween, the seal member 47 does not spread even if the tightening band 51 is bolted. The seal pressing member 49 prevents the deformation of the sealing members by closely contacting with the joint portions 41 and 43.

Further, as described above, the seal pressing member 49 prevents the exhaust gas from flowing into the bead portion 45 to prevent the generation of abnormal noise due to the vortex flow, and also prevents the pressure loss to the engine. It will be.

As described above, in this embodiment, since the exhaust pipes 37, 39 can be connected to each other without welding, the exhaust pipes 37, 39 can be made thinner. At the same time, the risk of intergranular corrosion disappeared.

Further, according to the present embodiment, even if the joint portions 41, 43 of the exhaust pipes 37, 39 are tightened with the tightening band 51, the seal member 47 prevents the joint portions 41, 43 from being deformed. As compared with the prior art, the strength of the connecting portion is improved, and the exhaust pipes 37, 39 can be reused.

5 and 6 show a second embodiment of the present invention. In the drawings, 65 and 67 are two exhaust pipes to be connected, and like the exhaust pipes 37 and 39, their respective connection end portions are connected. The sides 65a and 67a are flared to form a conical shape. The connection ends 65a and 67a are respectively provided with substantially bowl-shaped joints 69 and 71 with their openings facing outward, and the exhaust pipe 67 has one exhaust pipe 67 inside the other exhaust pipe 67. By inserting the joint portion 69 of the pipe 65, an annular bead is provided at the connecting portion of the exhaust pipes 65 and 67.

An annular metallic seal member 75 having a bead portion 73 that adheres to the entire inner circumferences of the lapped joint portions 69 and 71 is formed inside both the connection ends 65a and 67a. The exhaust pipes 65 and 67 are fitted and arranged in the same size as the inner diameters of the exhaust pipes 65 and 67.

Also in the present embodiment, the seal pressing member 49 is welded to the inner circumference of the tubular portion 77 of the seal member 75 on the same axis as the exhaust pipes 65 and 67 with the bead portion 73 interposed therebetween. By welding the seal pressing member 49 to the tubular portion 77 of the seal member 75 in this manner, deformation of the seal member 75 at the time of tightening the joint portions 69 and 71 is prevented, and The generation of abnormal noise is prevented by eliminating the inflow of exhaust gas into the bead portion 73.

Reference numeral 79 is a tightening band that is fitted and arranged on the outer peripheral surface side of both joints 69 and 71 of the exhaust pipes 65 and 67 and tightens them. The tightening band 79 is the tightening band in the first embodiment. Like the attached band 51, it is composed of a pair of split tightening bands 79a and 79b.

Each divided tightening band 79a, 79b is also formed with a bead portion 81 covering the outer peripheral surface of both joints 69, 71 along the longitudinal direction. In order to improve the tightening force per hit, in this embodiment, two bead portions 83 and 85 are further formed in the bead portion 81 in the longitudinal direction as shown in FIGS. The lap portion of the joint portions 69, 71 of the exhaust pipes 65, 67 and the three portions from the joint portions 69, 71 to the flare portions of the exhaust pipes 65, 67 are fastened to each other.

In addition, in the figure, 87 is a reinforcing flange provided on the side edge of each split tightening band 79a, 79b, and 89 is a bolt tightening portion. Since the joint structure according to the second embodiment is configured in this way, in order to connect both the exhaust pipes 65 and 67, first, the seal member 75 having the seal pressing member 49 welded to the inner circumference is attached to one exhaust pipe. After fitting and arranging in the exhaust pipe 67, the seal member 75 is fitted in the other exhaust pipe 67, and the joint 69 of the exhaust pipe 65 is lapped and inserted in the joint 71 of the exhaust pipe 67. The sealing member 75 is brought into close contact with the inner peripheral surfaces of the joint portions 69 and 71. Next, the split tightening bands 79a and 79b are respectively fitted and arranged on the outer peripheral surface sides of both joints 69 and 71, and these bolt tightening portions 89 are bolted, whereby both joints 69 and 71 are joined. The lap portion is tightened by the tightening band 79 so that both the exhaust pipes 65 and 67 are connected.

By connecting the exhaust pipes 65 and 67 in this manner, the bead portion 73 of the seal member 75 is brought into close contact with the inner peripheral surfaces of both the joint portions 69 and 71, so that the exhaust gas is exhausted by the seal member 75. The sealing property of the connecting portion of the pipes 65 and 67 is ensured, and the tubular portion 77 of the sealing member 75 sandwiching the bead portion 73 is welded to the seal pressing member 49. Therefore, the tightening band 79 is bolted. Even if the seal member 75 does not spread, the seal member 75 comes into close contact with the joint portions 69 and 71 and prevents the deformation thereof.

Further, as described above, the seal pressing member 49 prevents the exhaust gas from flowing into the bead portion 73 to prevent the generation of abnormal noise due to the vortex flow, and also prevents the pressure loss to the engine. It will be.

As described above, also in this embodiment, the exhaust pipes 65 and 67 can be connected to each other without welding, and the seal member 75 prevents the joints 69 and 71 from being deformed. Therefore, it is possible to achieve the intended purpose as in the first embodiment.

Further, according to this embodiment, in order to improve the tightening force per unit area of the tightening band 79, two bead parts 83 and 85 are further formed in the bead part 81 in the longitudinal direction, The lap portions of the joint portions 69, 71 of the exhaust pipes 65, 67 and the three portions from each joint portion 69, 71 to the flare portion of the exhaust pipes 65, 67 can be fastened with a fastening band 79. Therefore, the tightening force of the tightening band 79 is improved as compared with the first embodiment, and as a result, the sealing property is further improved, and the sealing property can be secured even if the part precision is slightly poor.

In the first and second embodiments, the tightening bands 51 and 79 are formed by the pair of split tightening bands 51a, 51b, 79a and 79b, and the bolt tightening portions are provided at both ends of each of them. Although the connection portions of the exhaust pipes 37, 39, 69, 71 are tightened by bolting 53, 89, the shape of the tightening bands 51, 79 is not limited to those of the above-mentioned embodiments. Alternatively, for example, a tightening band having a shape such as a known C-shaped clamp may be used, or one of the bolt tightening portions 53, 89 of the split tightening bands 51a, 51b, 79a, 79b may be used. The insertion structure may be used and the bolts may be tightened at one place, and even with these tightening bands, the intended purpose can be achieved as in the above-described embodiments.

[0034]

[Effect of the device]

 As described above, according to the present invention, these can be connected without welding to the exhaust pipe, so that the exhaust pipe can be made thin and there is no risk of intergranular corrosion.

In addition, according to the present invention, even if the joint portion of the exhaust pipe is tightened with the tightening band, the seal member prevents the joint portion from being deformed, so that the strength of the connecting portion is improved as compared with the conventional case. The exhaust pipe can be reused.

[Brief description of drawings]

FIG. 1 is a sectional view of an exhaust pipe joint structure according to a first embodiment of the present invention.

FIG. 2 is a side view of a seal member.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a plan view of the joint structure shown in FIG.

FIG. 5 is a sectional view of an exhaust pipe joint structure according to a second embodiment of the present invention.

FIG. 6 is a plan view of the joint structure shown in FIG.

FIG. 7 is a side view of a conventional exhaust pipe joint structure.

FIG. 8 is a side view of a conventional exhaust pipe joint structure.

FIG. 9 is a cross-sectional view of a conventional exhaust pipe joint structure.

FIG. 10 is a perspective view of a conventional exhaust pipe joint structure.

[Explanation of symbols]

 37, 39, 65, 67 Exhaust pipe 37a, 39a, 65a, 67a Connection end part 41, 43, 69, 71 Joint part 45, 55, 73, 81, 83, 85 Bead part 47, 75 Seal member 49 Seal pressing member 51,79 Tightening band

Claims (1)

[Scope of utility model registration request] 1. Each connecting end (37a, 39a, 65a,
67a) two exhaust pipes (37, 39, 65, 67) having substantially bowl-shaped joints (41, 43, 69, 71) each having an opening facing outward, and an exhaust pipe (37 , 39,
65, 67) both connection ends (37a, 39a, 65a,
67a) are fitted and arranged in the both joint portions (41, 4).
3,69,71) A ring-shaped metallic seal member (47,75) formed in a shape and size that closely adheres to the inner peripheral surface of
And a cylindrical metal seal pressing member (49) fixed to the inner periphery of the seal member (47, 75) on the same axis as the exhaust pipes (37, 39, 65, 67), and the both connections described above. An exhaust pipe joint structure comprising: a tightening band (51, 79) fitted and arranged on the outer circumference of an end (37a, 39a, 65a, 67a).