JP3807524B2 - Exhaust exhaust muffler for automobile and its manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of an automobile exhaust muffler having a tail tube without welding and having a tail tube attached to a muffler main body by caulking and fixing by ridge locking, and a manufacturing method thereof.
[0002]
[Prior art]
Conventionally, as an automobile exhaust muffler having a welding-less muffler pipe, the one described in JP-A-4-8818 is known.
[0003]
In this exhaust muffler for automobiles, a single muffler pipe is fixed to the end plate, as shown in FIG. 6, and fixed by caulking by ridge lock processing, in which two expansion nodes are formed at the front and rear positions of the pipe hole flange portion of the end plate. The muffler pipe is fixed without welding. The exhaust muffler to which the caulking fixing method by the ridge lock process is applied is a sub muffler provided in the middle of the exhaust system and having one muffler pipe passing through two end plates.
[0004]
Therefore, when this caulking fixing method by ridge lock processing is applied to fixing the tail tube of the main muffler provided at the end of the exhaust system, as shown in FIG. 7, the tail tube is inserted inside the muffler pipe on the muffler body side. The tail tube is caulked and fixed by a ridge lock process in which two spread-out nodes are formed at the overlapping portion.
[0005]
[Problems to be solved by the invention]
However, as shown in FIG. 7, when the caulking fixing method by the ridge lock process, which is well known as a muffler pipe fixing method, is applied to the fixing of the tail tube of the main muffler, a gap is formed in the overlapping portion of the muffler pipe and the tail tube, There is a problem that gas leakage occurs.
[0006]
That is, during the ridge lock process that pushes the overlapping part of the muffler pipe and the tail tube from the inside with the divided mandrel, the muffler pipe and the tail tube are in close contact with each other due to the pressure contact force. When contracted, the pipe diameter and tube diameter change due to restoring deformation within the elastic deformation range, and although the close contact is partially secured with the diameter change, most of the contact surfaces are separated from each other with the release of the pressure contact force A gap is created.
[0007]
Further, in the case of the tail tube, when an exhaust gas leak occurs, it is known from the outside, and unlike the sub-muffler provided in the middle of the exhaust system, the exhaust gas leak is not allowed.
[0008]
An object of the present invention is to provide an exhaust muffler for an automobile that realizes caulking and fixing of a tail tube by ridge lock processing by preventing gas leakage, and for an automobile that realizes diversification of mufflers while being advantageous in cost. An object of the present invention is to provide a method for manufacturing an exhaust muffler.
[0009]
[Means for Solving the Problems]
(Solution 1)
The invention according to claim 1, which solves the above problem, is an automobile exhaust muffler in which a tail tube is fixed to a muffler pipe provided through an end plate of a muffler main body, and the outer periphery of the fixed portion that overlaps the muffler pipe. The tube of the end plate is formed in a portion where the muffler pipe and the tail tube overlap each other with the muffler pipe protruding slightly outward from the pipe hole flange portion of the end plate. characterized by being caulked more done tail tube to the ridge lock processing for molding the two the spreading section before and after the position of the hole flange to the muffler body.
[0010]
(Solution 2)
According to a second aspect of the present invention for solving the above-mentioned problem, in a method of manufacturing an exhaust muffler for an automobile in which a tail tube is fixed to a muffler pipe provided through an end plate of a muffler main body, a little from a pipe hole flange portion of the end plate. Prepare a muffler body with a muffler pipe projecting outside, and a tail tube with a bite groove formed in advance on the outer peripheral surface of the fixed part that overlaps with the muffler pipe, and insert a ridge lock processing means to form two spread-out nodes inside the tail tube At the same time, the tail tube is inserted inside the end of the muffler pipe of the muffler body, and the tail tube and muffler pipe that overlap each other are pushed and expanded while the biting groove of the tail tube bites into the inner surface of the muffler pipe by the operation of the ridge lock processing means. Pipe hole in plate Characterized by being caulked and fixed to the tail tube at retrofitted to the muffler body by molding the two sections at the longitudinal position of the Nji portion.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
First, the configuration will be described.
[0014]
The first embodiment corresponds to the first and second aspects of the invention.
[0015]
1 is an enlarged cross-sectional view showing a tail tube fixing portion of an exhaust muffler for an automobile according to Embodiment 1, FIG. 2 is a view showing a tail tube used in the exhaust muffler for an automobile according to Embodiment 1, and FIG. It is explanatory drawing of the tail tube fixing method by the ridge lock process of the exhaust muffler for vehicles of form 1.
[0016]
In FIG. 1, 1 is a rear end plate (end plate), 2 is a muffler outlet pipe (muffler pipe), and 3 is a tail tube.
[0017]
The rear end plate 1 is an end plate (end plate) provided at the rear end portion of the muffler shell with respect to the front end plate provided at the front end portion of the cylindrical muffler shell (not shown), and is a pipe through which the muffler outlet pipe 2 passes. A hole flange portion 1a is formed.
[0018]
The muffler outlet pipe 2 defines a muffler inner chamber surrounded by a cylindrical muffler shell (not shown), a front end plate, and a rear end plate 1 into a plurality of chambers by a baffle plate (not shown). A pipe that exhausts exhaust gas from one chamber to the outside with respect to the muff linelet pipe to be introduced and the pipe in the muffler that communicates the two chambers, and is provided slightly protruding from the pipe hole flange portion 1a of the rear end plate 1 ing.
[0019]
A muffler main body is configured by the configuration including the muffler shell, the front end plate, the rear end plate 1, the baffle plate, the muffle linelet pipe, the muffler inner pipe, and the muffler outlet pipe 2, that is, the configuration excluding only the tail tube 3.
[0020]
As shown in FIG. 2, the tail tube 3 has an annular biting groove 3a (biting groove) in which a plurality of annular grooves whose adjacent grooves are independent from each other are arranged on the outer periphery of the fixed portion overlapping the muffler outlet pipe 2. Is formed.
[0021]
As shown in FIG. 1, the tail tube 3 is fixed to the muffler outlet pipe 2 by caulking and fixing by ridge lock forming two expanded nodes R1 and R2 at the front and rear positions of the pipe hole flange portion 1a of the rear end plate 1. It is said that.
[0022]
The plate thickness of the muffler outlet pipe 2 and the tail tube 3 is set so that the muffler outlet pipe 2 side is thin (for example, 0.6 mm), and the plate thickness on the tail tube 3 side is set to be thick (for example, 1.2 mm). Therefore, both the weight reduction of the muffler main body, which occupies an important position for the lightweight exhaust system, and the securing of the deformation resistance of the tail tube 3 that suppresses deformation even when there is a collision with a stepping stone or the like are achieved.
[0023]
Next, the operation will be described.
[0024]
[Exhaust muffler manufacturing method]
A method for manufacturing an automobile exhaust muffler in which the tail tube 3 is fixed to a muffler outlet pipe 2 provided through the rear end plate 1 of the muffler body will be described.
[0025]
First, a muffler body having a muffler outlet pipe 2 protruding slightly from the pipe hole flange portion 1a of the rear end plate 1 is prepared.
[0026]
In addition to the muffler main body, a tail tube 3 is prepared in which an annular biting groove 3a is formed in advance on the outer peripheral surface of the fixed portion that overlaps with the muffler outlet pipe 2.
[0027]
As shown in FIG. 3, a taper bar 4b is slidably provided on a hollow cylindrical pipe case 4a as a ridge-locking means for forming the two expansion nodes R1 and R2, and the periphery of the taper portion of the taper bar 4b is provided. A finger 4c having two ridges by dividing into eight parts is arranged on the upper part, and the fingers 4c divided into eight parts are connected by a connecting ring 4d. The tapered bar 4b is fixed to the fixed pipe case 4a in FIG. An eight-divided type ridge lock processing device 4 that expands the outer diameter of the eight-divided fingers 4c by pressing and sliding in the right direction is used.
[0028]
After the ridge lock processing device 4 is inserted inside the tail tube 3, the tail tube 3 is inserted into the end of the muffler outlet pipe 2 of the muffler body, or the tail tube 3 is inserted into the muffler outlet pipe 2 of the muffler body. After being inserted into the end portion, the ridge lock processing device 4 is inserted into the tail tube 3 so as to be in the state shown in the lower half of the center line of FIG.
[0029]
Then, the tail tube 3 and the muffler outlet pipe 2 that overlap each other are connected to each other by the operation of the ridge lock processing device 4 that pressurizes and slides the taper bar 4b in the right direction in FIG. The muffler body 3 is retrofitted by forming the two grooves R1 and R2 at the front and rear positions of the pipe hole flange portion 1a of the rear end plate 1 by expanding the biting groove 3a while biting into the inner surface of the muffler outlet pipe 2. It is fixed to caulking.
[0030]
After the caulking is fixed, the taper bar 4b is slid in the left direction in FIG. 3 with respect to the fixed pipe case 4a to reduce the outer diameter of the eight-divided fingers 4c. It is pulled out.
[0031]
[Gas leakage prevention]
The gas leakage preventing action when the caulking is fixed by the ridge lock processing will be described.
[0032]
A large pressure contact force acts on the muffler outlet pipe 2 and the tail tube 3 during the ridge lock process in which the overlapped portion between the muffler outlet pipe 2 and the tail tube 3 is pushed out from the inside by the divided fingers 4c. The annular biting groove 3 a that has been cut into the inner surface of the muffler outlet pipe 2. Then, when the diameter of the finger 4c is reduced after the processing is finished, the pressure contact force is released and an attempt is made to restore and deform in the elastic deformation range. However, the biting force is maintained as it is in a portion where the biting force by the annular biting groove 3a is larger than the restoring force. Even if the biting force is smaller than the restoring force, the biting amount is reduced or only a slight gap is formed. Therefore, a large number of tight seal portions are formed in an annular shape by biting by the annular biting groove 3a, and exhaust gas leakage is reliably prevented.
[0033]
In particular, since the biting groove is an annular biting groove 3a, even if a gap is partially generated, the gap itself is an annular shape and cannot be an exhaust gas passage, and as long as the annular biting is ensured at the front and rear portions of the gap, Exhaust gas leakage is surely prevented.
[0034]
[Muffler diversification]
For example, when there is a difference in the muffler specifications, such as when the tail tube is a straight pipe type, when the tail tube is equipped with a diffuser, when the tail tube is equipped with a control valve, etc. The muffler was designed and manufactured.
[0035]
However, as described above, since the method of fixing the tail tube 3 to the muffler main body by retrofitting is adopted, the muffler main body having the same specifications is prepared, and the tail tube 3 having various specifications is prepared. It can cope with muffler diversification, achieve a significant cost reduction, and expand the range of muffler diversification, such as preparing a tail tube aiming at the apparent effect.
[0036]
Next, the effect will be described.
[0037]
(1) On the outer periphery of the fixed portion overlapping the muffler outlet pipe 2, the tail tube 3 is formed with an annular biting groove 3a in which a large number of annular grooves whose adjacent grooves are independent from each other are formed, and the tail with respect to the muffler outlet pipe 2 Since the tube 3 is fixed by caulking by ridge lock processing in which two expansion nodes R1 and R2 are formed at the front and rear positions of the pipe hole flange portion 1a of the rear end plate 1, the tail tube 3 by ridge lock processing is used to prevent gas leakage. It is possible to provide an automobile exhaust muffler that achieves the caulking and fixing.
[0038]
(2) A muffler body having a muffler outlet pipe 2 projecting slightly outward from the pipe hole flange portion 1a of the rear end plate 1, and a tail tube 3 in which an annular biting groove 3a is formed in advance on the outer peripheral surface of the fixed portion overlapping the muffler outlet pipe 2 The ridge lock processing device 4 for forming the two expansion nodes R1 and R2 is inserted into the tail tube 3, and the tail tube 3 is inserted into the end portion of the muffler outlet pipe 2 of the muffler body, By the operation of the lock processing device 4, the tail tube 3 and the muffler outlet pipe 2 that overlap each other are expanded while the annular biting groove 3 a of the tail tube 3 is biting into the inner surface of the muffler outlet pipe 2, and the pipe hole flange portion of the end plate 1 Two nodes R at the front and rear position of 1a , Because of the caulked tail tube 3 at retrofitting by molding the R2, it is possible to provide a manufacturing method of an automotive exhaust muffler to achieve a cost-is advantageous while muffler diversification.
[0039]
(3) Since the biting groove formed in the tail tube 3 is an annular biting groove 3a in which a large number of annular grooves whose adjacent grooves are independent from each other are arranged on the outer periphery of the fixing portion overlapping the muffler outlet pipe 2, Exhaust gas leakage can be reliably prevented by a large number of tightly sealed seal portions with reduced communication.
[0040]
(4) The thickness of the muffler outlet pipe 2 and the tail tube 3 is set so that the thickness of the muffler outlet pipe 2 is small and the thickness of the tail tube 3 is thick. It is possible to achieve both of ensuring the deformation strength.
[0041]
(Other embodiments)
In the first embodiment, the biting groove formed in the tail tube 3 is an annular biting groove 3a in which a large number of annular grooves whose adjacent grooves are independent from each other are arranged on the outer periphery of the fixed portion overlapping the muffler outlet pipe 2. As shown in FIG. 4, as shown in FIG. 4, the biting groove formed in the tail tube 3 may be a net-like biting groove 3b in which slanting grooves are crossed in a net shape. A mesh-like biting groove 3b can be formed.
[0042]
In the first embodiment, an example in which the ridge lock processing device 4 of an eight-divided type is used as the ridge lock processing means is shown. However, as shown in FIG. 5, a hollow cylindrical first taper bar 5a and a first taper bar are used. A second taper bar 5b slidably provided on 5a, a first mandrel 5c and a second mandrel 5d which are taper-fitted to the taper bars 5a and 5b, a spacer 5e and both mandrels 5c and 5d, respectively. The configuration includes a first urethane rubber 5f and a second urethane rubber 5g sandwiched therebetween, and two taper bars 5a, 5b are slid under pressure toward both the urethane rubbers 5f, 5g. A urethane type ridge lock processing device 5 that sandwiches and deforms the urethane rubbers 5f and 5g to expand the outer diameter may be used.
[0043]
【The invention's effect】
According to the first aspect of the present invention, in an automobile exhaust muffler in which a tail tube is fixed to a muffler pipe provided through an end plate of a muffler body, the tail tube bites into an outer peripheral surface of a fixed portion overlapping the muffler pipe. The tube is formed with a groove, and the tail tube is fixed to the muffler pipe. The pipe hole flange of the end plate is located at the portion where the muffler pipe and the tail tube overlap each other with the muffler pipe protruding slightly from the pipe hole flange portion of the end plate. since more perform tail tube to the ridge lock processing for molding the two the spreading section before and after the position of the parts was caulked to the muffler body, exhaust automobile tail tube by a ridge lock processing is realized that is caulked to the muffler body Effect is obtained that it is possible to provide a hula.
[0044]
In the invention according to claim 2, in the method of manufacturing an exhaust muffler for an automobile in which a tail tube is fixed to a muffler pipe provided through an end plate of a muffler body, a slightly outside from a pipe hole flange portion of the end plate. Prepare a muffler body with a projecting muffler pipe and a tail tube with a bite groove formed in advance on the outer peripheral surface of the fixed part that overlaps with the muffler pipe, and insert a ridge-lock processing means to form two push-out joints inside the tail tube. The tail tube is inserted into the end of the muffler pipe of the muffler body, and the ridge lock processing means is operated to expand the tail tube and muffler pipe that overlap each other while pushing the biting groove of the tail tube into the inner surface of the muffler pipe. Pipe hole flange Since it has been caulked tail tube at retrofitted to the muffler body by molding the two sections at the rear position, it is possible to provide a manufacturing method of an automotive exhaust muffler to achieve a cost-is advantageous while muffler diversification The effect is obtained.
[Brief description of the drawings]
FIG. 1 is an enlarged sectional view showing a tail tube fixing portion of an automobile exhaust muffler according to a first embodiment.
FIG. 2 is a diagram showing a tail tube used in the automobile exhaust muffler according to the first embodiment.
FIG. 3 is an explanatory diagram of a tail tube fixing method by ridge lock processing of an automobile exhaust muffler according to the first embodiment.
FIG. 4 is a diagram showing another embodiment of a tail tube used in an automobile exhaust muffler.
FIG. 5 is a view showing another embodiment of a ridge lock processing means used for manufacturing an exhaust muffler for an automobile.
FIG. 6 is a partially broken perspective view showing a fixed state of a muffler pipe by a conventional ridge lock process.
FIG. 7 is a half sectional view showing a tail tube fixing portion when a conventional muffler pipe fixing method by ridge lock processing is applied to fixing a tail tube.
[Explanation of symbols]
1 Rear end plate (end plate)
1a Pipe hole flange part 2 Muffler outlet pipe (muffler pipe)
3 Tail tube 3a Annular groove (bite groove)
4 Ridge lock processing equipment (ridge lock processing means)
R1, R2 expansion joint

Claims (2)

In an automobile exhaust muffler in which a tail tube (3) is fixed to a muffler pipe (2) provided through an end plate (1) of a muffler body,
The tail tube (3) is a tube in which a biting groove (3a) is formed on the outer peripheral surface of the fixed portion overlapping the muffler pipe (2),
The muffler pipe (2) and tail tube are fixed to the muffler pipe (2) with the muffler pipe (2) protruding slightly from the pipe hole flange (1a) of the end plate (1). (3) two the spreading section before and after the position of the pipe hole flange portion of the end plate (1) (1a) in a portion overlapping each other (R1), (R2) and more carried tail tube to the ridge lock processing for forming the (3 ) Is fixed to the main body of the muffler. In an automobile exhaust muffler manufacturing method for fixing a tail tube (3) to a muffler pipe (2) provided through an end plate (1) of a muffler body,
A muffler body having a muffler pipe (2) projecting slightly outward from the pipe hole flange (1a) of the end plate (1), and a tail having a bite groove (3a) formed in advance on the outer peripheral surface of the fixed portion overlapping the muffler pipe (2) Prepare tube (3),
The ridge lock processing means (4) for forming the two expansion nodes (R1) and (R2) is inserted into the tail tube (3), and the tail tube (3) is connected to the end of the muffler pipe (2) of the muffler body. Insert it inside,
By the operation of the ridge lock processing means (4), the tail tube (3) and the muffler pipe (2) that overlap each other are pushed and expanded while the biting groove (3a) of the tail tube (3) is biting into the inner surface of the muffler pipe (2), The tail tube (3) is caulked and fixed to the muffler body by retrofitting by forming two nodes (R1) and (R2) at the front and rear positions of the pipe hole flange (1a) of the end plate (1). A method for manufacturing an exhaust muffler for automobiles.

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