JPS6128010Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] This invention relates to an improvement in an exhaust pipe connection device.

[Conventional technology]

A conventional exhaust pipe connection device is shown in FIGS. 1 and 2. In the figure, 1 and 1' are exhaust pipes that have been cut off in the middle, and 2
is a bellows consisting of a corrugated portion 3 and both end cylindrical portions 4, 4', and the both end cylindrical portions 4, 4' of the bellows 2 are fitted onto the pipe ends of the exhaust pipes 1, 1' and are fully welded. ing.

However, in the case of this conventional device, the bellows 2
There was a problem in that the vibration resistance was weak in the outermost troughs A and A' of the corrugated portion 3, making them susceptible to damage. The reason for this is that the valleys A and A' are always exposed to high-temperature exhaust gas passing through the exhaust pipes 1 and 1', and both end cylinder parts 4 and 4' of the bellows 2 are completely exposed to the exhaust pipes 1 and 1'. Since the exhaust pipes 1, 1' are welded, the heat of the exhaust pipes 1, 1' is immediately transferred from the respective end cylinder parts 4, 4' to the valley parts A, A', and furthermore, the exhaust pipes 1, 1' are
1' When the bellows 2 absorbs the relative displacement that occurs between them due to their unique vibrations, the greatest stress is applied to the valleys A and A' located at both ends of the bellows 2, causing them to bend. Combined with the high degree of damage, it was thought that the damage would occur quickly.

Therefore, as shown in Japanese Utility Model Publication No. 52-25534 or as shown in FIG.
An exhaust pipe connecting device has been proposed in which the troughs A and A' are not directly exposed to high-temperature exhaust gas.

[Problem that the invention attempts to solve]

According to such an exhaust pipe connection device, the valleys A,
Although the direct exposure of A' to high-temperature exhaust gas has been eliminated, the cylinder parts 4 and 4' at both ends of the bellows 2 are still fully welded to the exhaust pipes 1 and 1', so 1' was immediately transferred from the two end tube portions 4, 4' to the troughs A, A', and it was not possible to prevent the troughs A, A' from increasing in temperature. For this reason, the troughs A and A', which bend to a large degree during vibration absorption, still have the disadvantage of being easily damaged.

[Purpose of invention]

This idea was devised in view of the above circumstances, and it greatly reduces the amount of heat transmitted through the cylindrical parts at both ends of the bellows, prevents damage to the outermost valley part of the bellows, and makes it durable for long-term use. The object of the present invention is to provide an exhaust pipe connection device that can be obtained.

[Means for solving problems]

In order to achieve this purpose, this invention provides an exhaust pipe connection device in which an exhaust pipe is cut off in the middle, and both ends of the bellows are externally welded to the opposing ends of the exhaust pipe. is a tapered portion that gradually expands inward from its tip, and both tips of the tapered portion are provided with narrow welding margins.

[Effect of invention]

According to this idea, since the contact area between the exhaust pipe and the bellows is small, the amount of heat transferred to the bellows is small, and moreover, the heat transferred to the bellows is released into the outside air while traveling through the tapered part. becomes.

[Example of idea]

Hereinafter, an embodiment of this invention will be described based on FIGS. 3 and 4. Note that the same parts as in the above conventional example are indicated by the same reference numerals.

FIG. 3 shows a first embodiment of this invention, in which both end cylindrical parts 4, 4' of the bellows 2 are sequentially expanded inward from their tips to create a gap 12 between them and the exhaust pipes 1, 1'.
The tapered part 11 is formed by reducing the area of contact with the exhaust pipes 1 and 1'.
In order to reduce the amount of heat transferred to the exhaust pipes 1 and 1, both ends of the tapered part 11 are externally welded to the exhaust pipes 1 and 1' as a narrow welding margin 10.

Therefore, the welding allowance 10 in contact with the exhaust pipes 1, 1'
is a part of the tip of the both end cylindrical parts 4, 4' of the bellows 2, and as in the conventional case, the both end cylindrical parts 4, 4' of the bellows 2 are
4' is in complete contact with the exhaust pipes 1, 1', the contact area is small, and the tapered part 11 is provided to create a gap 1 between the exhaust pipes 1, 1'.
2, and connect the exhaust pipe 1 to the tapered part 11.
1' is prevented from being transferred, and a small amount of heat transferred from the welding allowance 10 can be released into the outside air while being transmitted through the tapered part 11. Since the amount of heat transferred to A and A' is reduced and the temperature of valleys A and A' is lowered, heating of the bellows 2 does not reduce vibration resistance or damage, etc., and has various excellent effects. .

FIG. 4 shows an enlarged sectional view of a main part in a second embodiment of this invention, and in this embodiment, a corrugated uneven portion 13 is further formed on the tapered portion 11.

Even in this case, as in the first example above, since the contact area between the exhaust pipes 1, 1' and the welding allowance 10 is small, the amount of heat transferred to the bellows 2 is small; is released into the outside air while passing through the tapered portion 11. However, in this embodiment, the surface area of the tapered portion 11 is increased, so the heat release effect is improved. By extending the distance to ', the amount of heat transferred to the valleys A and A' was significantly reduced compared to the first example. Furthermore, in this embodiment, the exhaust pipes 1, 1'
When the bellows 2 absorbs the relative displacement that occurs between them due to their respective unique vibrations, the corrugated concave and convex portions 13 provided on the tapered portion 11 perform a vibration absorbing function, so that the troughs A, A Coupled with the fact that the degree of bending of the valleys A and A' can be reduced, it is possible to more reliably prevent a decrease in the vibration resistance strength and damage of the valleys A and A'.

[Effect of idea]

As described above, this invention reduces the amount of heat transferred from the both ends of the bellows to the valley, and prevents damage to the bellows by discharging the transferred heat. It can be used for a long time.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of a conventional exhaust pipe connecting device, and FIG. 3 is a cross-sectional view of the first embodiment of this invention.
FIG. 4 is an enlarged sectional view of a main part in a second embodiment of this invention. 1,1'...Exhaust pipe, 2...Bellows, 3...
Waveform part, 4, 4'...Both end cylinder part, 10...Welding allowance, 11...Tapered part, 12...Gap part, 13
...Uneven areas.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In an exhaust pipe connection device in which an exhaust pipe is cut in the middle and both ends of the bellows are externally welded to the opposing pipe ends, the ends of the bellows are An exhaust pipe connection device characterized by having a tapered portion that gradually expands inward from its tip, and having narrow welding margins at both tips of the tapered portion. (2) The exhaust pipe connection device according to claim 1, wherein the tapered portion has a wave-like unevenness.