JP2004162641A - Manufacturing method for catalytic converter, and aligning tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a catalytic converter in which an article to be housed including a catalyst holding body is smoothly and surely press-fitted or inserted into two approximately cylindrical housing parts of a converter case whose bent part is formed between the housing parts, and to provide an aligning tool used for the manufacturing method. <P>SOLUTION: The aligning tool (tool body 31) having a mounting face 33 inclined from an installation face P in working is prepared. An end part of one of two cylindrical housing parts 11, 12 of the converter case is brought into contact with and disposed on the inclined mounting face 33 of the aligning tool, so that the other housing part out of two housing parts 11, 12 is vertically stands on the installation face P. An article to be housed 24 or an article to be housed 23 including the catalyst holding body is press-fitted or inserted into the installation face P from a normal line direction. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a catalytic converter provided in an exhaust system of a vehicle internal combustion engine and the like, and a shaft alignment jig.
[0002]
[Prior art]
In general, a catalytic converter is configured by press-fitting a wound body formed by winding a mat-shaped holding sealing material around a ceramic catalyst holding body into a substantially cylindrical metal case. Even if the entire volume of the ceramic catalyst holder is the same, it is better to divide it into a plurality and house it separately in the case, so that the exhaust purification performance is better, so reduce the diameter of the center of the long cylindrical case, In some cases, a catalyst holding body around which a holding sealing material is wound is disposed in a large-diameter accommodation space located before and after the reduced-diameter portion (small-diameter portion) (see, for example, Patent Document 1).
[0003]
[Patent Document 1] JP-A-2001-342826 (abstract)
[0004]
[Problems to be solved by the invention]
However, in the catalytic converter of Patent Literature 1, since the converter case extends straight, splitting of the catalyst holder into a plurality of pieces promotes the overall length of the catalytic converter. Therefore, there may be inconveniences such as difficulty in securing a mounting space at the time of mounting on a vehicle and waste of the exhaust pipes. On the other hand, there is an attempt to solve the problem of mounting on a vehicle by making the converter case bend in the middle. However, if the converter case has a bent shape in the middle, it becomes difficult to press-fit the wound body made of the catalyst holding body and the holding sealing material into each of the housing portions located before and after the bent portion of the case. In particular, it is difficult to apply a press-fitting machine for press-fitting the wound body into each of the housing portions of the case, and there is a fear that productivity may be reduced. The present invention has been made in view of such circumstances.
[0005]
An object of the present invention is to smoothly and surely press-fit or insert an object including a catalyst holder into each of the housing portions of a converter case in which a bent portion is formed between two substantially cylindrical housing portions. It is an object of the present invention to provide a possible method of manufacturing a catalytic converter. It is still another object of the present invention to provide a jig for use in carrying out the method.
[0006]
[Means for Solving the Problems]
A first invention is a method for manufacturing a catalytic converter, comprising: a converter case having a bent portion formed between two substantially cylindrical housing portions; and an accommodation object including a catalyst holder. A jig having a mounting surface inclined with respect to the installation surface of the converter case is prepared, and a cylindrical end of one of the two housing portions of the converter case is inclinedly mounted on the shaft alignment jig. After the remaining housing portion of the two housing portions is almost vertically erected with respect to the installation surface by being arranged in contact with the surface, the catalyst holding body is moved to the erected housing portion. A method for manufacturing a catalytic converter, comprising press-fitting or inserting a contained object from a direction normal to the installation surface.
[0007]
According to this method, at the time of assembling the catalytic converter, the cylindrical end portion of one of the two housing portions of the converter case is brought into contact with the inclined mounting surface of the shaft alignment jig so as to be in contact with each other. The rest of the storage sections can be made substantially perpendicular to the installation surface. As a result, the axial direction of the accommodation section to be press-fitted or inserted is substantially parallel to the direction of press-fitting or inserting the object to be accommodated (that is, the normal direction of the installation surface), and is pressed or inserted in the normal direction of the installation surface. Axis alignment of the inserted object and the housing part to be pressed or inserted becomes easy. Therefore, according to this method, even when the converter case has a bent shape having a bent portion between the two substantially cylindrical housing portions, the housing case including the catalyst holding body is included in each housing portion of the case. It becomes possible to press-fit or insert an object smoothly and reliably.
[0008]
In addition, in the axis alignment jig used in this method, the inclination angle of the mounting surface with respect to the installation surface substantially coincides with the intersection angle between the central axes (L1, L2) of the two housing portions of the converter case. Preferably, it is set. By setting the inclination angle of the mounting surface, the operation and effect of the present method are maximized.
[0009]
According to a second aspect of the present invention, there is provided a shaft used for press-fitting or inserting an object containing a catalyst holding body into each of the accommodating portions of a catalytic converter case in which a bent portion is formed between two substantially cylindrical accommodating portions. A fitting jig, which is provided on the installation surface during operation, is provided with a receiving portion for receiving a housing portion of the converter case, and a bottom surface of the receiving portion is provided with the mounting surface. And a mounting surface for contacting and disposing the cylindrical end portion of the housing portion with respect to the mounting surface, and the tilt angle of the mounting surface with respect to the installation surface is set between the central axes of the two housing portions of the converter case. Characterized in that the jig is set so as to substantially coincide with the intersection angle.
[0010]
By using this alignment jig, even when the catalytic converter case has a bent shape having a bent portion between the two substantially cylindrical accommodating portions, the axial alignment jig is provided between the case and the installation surface. By interposing the tool, the housing portion of the converter case to be press-fitted or inserted with the object including the catalyst holding body can be made substantially upright with respect to the installation surface. Therefore, it becomes easy to align the object to be press-fitted or inserted from the normal direction of the installation surface with the housing part to be press-fitted or inserted, and the method for manufacturing the catalytic converter can be smoothly and reliably performed. It becomes.
[0011]
In the axis aligning jig of the present invention, it is preferable that a curved support surface is formed inside the receiving portion to support an outer peripheral side surface of the storage portion that is arranged in contact with the placement surface. Also, the jig main body includes a fixing unit (for example, a fixing unit) for fixing the converter case to the jig main body by clamping the accommodating portion arranged in contact with the mounting surface with the curved support surface. Bolts) are preferably provided.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
[0013]
(Components of catalytic converter)
As shown in FIG. 1A, the catalytic converter includes at least a cylindrical converter case 10 and two sets of objects 23 and 24 housed in the case 10. By welding flange members 21 and 22 to the upstream and downstream opening ends of the converter case 10, respectively, an exhaust manifold (so-called manifold) integrated with the catalytic converter is formed.
[0014]
The converter case 10 is integrally formed into a shape as shown in FIG. 1B by performing bulge forming (hydroforming) on a straight metal pipe (for example, a 1.5 mm thick stainless steel pipe). I have. That is, a bent portion 13 is formed in the middle of the cylindrical converter case 10, and two straight cylindrical housing portions 11 and 12 are provided before and after the bent portion 13 (up and down in the figure). The bent portion 13 is formed in a spool shape depressed toward the inside of the cylindrical body over the entire circumference of the case 10, so that the diameter of the bent portion 13 is smaller than that of the front and rear storage portions 11 and 12, and a boundary between the two storage portions is provided. At the same time, the mounting angle between the two housing portions 11 and 12 is changed. The bent portion 13 is engaged with the lower end of the stored object 23 to prevent the stored object 23 from further dropping even if the stored object 23 located on the upper side falls and falls. In other words, the bent portion 13 also has a role of preventing damage to the stored object 23 due to contact with the stored object 24 located below the bent portion 13.
[0015]
The upstream storage section 11 and the downstream storage section 12 have the same inner and outer diameters, and the opening end (cylinder end) of each storage section has an annular shape. On the other hand, with respect to the axial length of each housing portion, the upstream housing portion 11 is relatively short, and the downstream housing portion 12 is relatively long. Further, as a result of the converter case 10 having a shape bent at the bent portion 13, the central axis L1 of the upstream housing portion 11 and the central axis L2 of the downstream housing portion 12 intersect in the region of the bent portion 13. It is in. The intersection angle θ between both axes L1 and L2 is preferably in the range of 5 to 45 degrees (°). If the crossing angle θ exceeds 45 degrees, unevenness of the wall thickness becomes remarkable, and the inconvenience such as a decrease in the strength of the bent portion 13 is likely to occur.
[0016]
As shown in FIG. 1B, objects 23 and 24 having a total length corresponding to their respective axial lengths are press-fitted into the respective housing portions 11 and 12 of the converter case. The objects 23 and 24 are wound bodies formed by winding a mat-shaped holding sealing material (23b and 24b) around the outer periphery of a cylindrical catalyst holding body (23a and 24a). The catalyst holders 23a and 24a are so-called honeycomb structures made of a porous ceramic sintered body, and have an exhaust gas purification catalyst fixed or supported on the surface of each cell having the honeycomb structure. The holding sealing members 23b and 24b are made of a heat-resistant ceramic fiber such as alumina fiber solidified in a mat shape, and serve as a sealing material and interpose between the catalyst holding body and the inner wall surface of the case housing. This is a member that also serves as a holding material for stably holding the catalyst holding body in the case housing by applying a surface pressure.
[0017]
(Axis alignment jig)
As shown in FIGS. 2A and 2B, the main body 31 of the alignment jig has a rectangular parallelepiped shape, and its bottom surface (lower surface) is installed on the installation surface P of the worktable. A receiving portion 32 for receiving the accommodating portion 11 or 12 of the converter case is provided on the upper surface side of the jig body 31. At the bottom of the receiving portion 32, a mounting surface 33 inclined with respect to the installation surface P is formed. Further, a curved support surface 34 connected to the lowest position of the inclined mounting surface 33 and an upright wall surface 35 connected to the highest position of the inclined mounting surface 33 are formed inside the receiving portion 32. Have been. In other words, the receiving portion 32 that is recessed with respect to the upper surface of the jig body 31 is defined by the mounting surface 33, the support surface 34, and the upright wall surface 35. In addition, as can be seen from the geometrical drawing relationship of each auxiliary line shown in FIG. 2B, the inclination angle θ of the mounting surface 33 with respect to the installation surface P is determined by the center of the two accommodation portions 11 and 12 of the converter case. It is set to coincide with the intersection angle θ between the axes L1 and L2.
[0018]
The mounting surface 33 of the receiving portion is a surface on which the cylindrical end portion of one of the accommodating portions 11 or 12 of the converter case is brought into contact, and the curved supporting surface 34 is formed of the converter case received in the receiving portion 32. This is a surface for supporting the outer peripheral side surface of the housing portion 11 or 12. The upright wall surface 35 has no contact with the converter case. On the wall forming the upright wall surface 35, a fixing bolt 36 as a fixing means for fixing the converter case 10 to the alignment jig is screwed. Is being worn. The amount of protrusion of the fixing bolt 36 into the receiving portion 32 can be freely set by rotating the bolt.
[0019]
Next, an assembling procedure (that is, a manufacturing method) of the catalytic converter using the above-described alignment jig will be described. First, as shown in FIGS. 3A and 3B, the main body 31 of the alignment jig is installed on the installation surface P of the horizontal worktable. A press-fitting machine (not shown) for press-fitting the storage object 23 or 24 including the catalyst holding body into the converter case is disposed above the shaft alignment jig. The press-fitting direction of the object to be accommodated by the press-fitting machine is the vertical direction (that is, the direction normal to the horizontal installation surface P).
[0020]
As a first step, as shown in FIG. 3A, the upstream housing portion 11 which is a short portion of the bent converter case 10 is made to enter the receiving portion 32 of the shafting jig. Then, the converter case 10 is positioned with respect to the receiving portion 32 by bringing the cylindrical end portion of the upstream housing portion 11 into contact with the mounting surface 33 and bringing the outer peripheral side surface of the upstream housing portion 11 into contact with the curved support surface 34. Since the inclination angle θ of the mounting surface 33 with respect to the installation surface P coincides with the intersection angle θ between the two axis lines L1 and L2, the center axis L2 of the downstream housing portion 12 of the converter case is The upstream housing section 11 can be disposed so as to be orthogonal to the mounting surface 33 and the support surface 34. When the position of the converter case 10 is determined, the fixing bolt 36 is tightened to clamp the accommodating portion 11 between the tip of the bolt and the support surface 34, thereby restricting the rotation (rotation) of the converter case 10 around the axis L1. .
[0021]
As shown in FIG. 3 (A), as a result of the downstream-side housing portion 12 standing vertically with respect to the installation surface P, the direction of the center axis L2 matches the press-fitting direction (that is, the vertical direction) of the container 24 by the press-fitting machine. Therefore, if the alignment jig receiving the converter case 10 is horizontally moved on the installation surface P, or if the press-fitting machine holding the object 24 is horizontally moved, the downstream-side accommodating portion 12 of the converter case can be moved. Axis alignment with the object 24 can be easily performed. By operating the press-fitting machine after the shaft alignment, the object 24 formed by winding the catalyst holding body 24a with the holding sealing material 24b can be reliably pressed into the downstream-side housing portion 12. The vertical pressing force of the press-fitting machine acts perpendicularly to the installation surface P via the converter case 10 and the axis-aligning jig body 31. Therefore, at the time of press-fitting, the axis-aligning jig holding the converter case is mounted on the installation surface P. There is no slipping over P to escape sideways, and press-fitting is performed reliably.
[0022]
After the press-fitting of the object 24 into the downstream housing section 12 is completed, the converter case 10 is once removed from the alignment jig, the converter case 10 is inverted, and then the converter case 10 is attached again.
[0023]
That is, as shown in FIG. 3B, the downstream side housing portion 12 which is a long portion of the bent converter case 10 is made to enter the receiving portion 32 of the shafting jig as a second stage. Then, the converter case 10 is positioned with respect to the receiving portion 32 by bringing the cylindrical end portion of the downstream housing portion 12 into contact with the mounting surface 33 and the outer peripheral side surface of the downstream housing portion 12 into contact with the curved support surface 34. Since the inclination angle θ of the mounting surface 33 with respect to the installation surface P matches the intersection angle θ between the two axis lines L1 and L2, the center axis L1 of the upstream housing portion 11 of the converter case is The downstream-side accommodation section 12 can be arranged so as to be orthogonal to the placement surface 33 and the support surface 34. When the position of the converter case 10 is determined, the fixing bolt 36 is tightened to clamp the accommodating portion 12 between the tip end of the bolt and the support surface 34 to restrict the rotation (rotation) of the converter case 10 around the axis L2. .
[0024]
As shown in FIG. 3B, as a result of the upstream-side accommodation portion 11 standing upright with respect to the installation surface P, the direction of the center axis L <b> 1 coincides with the press-fitting direction of the object 23 by the press-fitting machine (that is, the vertical direction). Therefore, if the axial alignment jig receiving the converter case 10 is horizontally moved on the installation plane P or the press-fitting machine holding the object 23 is horizontally moved, the upstream accommodating portion 11 of the converter case is not required. Axis alignment with the object 23 can be easily performed. By operating the press-fitting machine after the shaft alignment, the object 23 formed by winding the catalyst holding body 23a with the holding sealing material 23b can be reliably pressed into the upstream housing portion 11. As described above, the vertical pressing force of the press-fitting machine acts vertically on the installation surface P via the converter case 10 and the shaft-matching jig main body 31. Therefore, the shaft-fixing jig holding the converter case at the time of press-fitting. Does not slide on the installation surface P and escape sideways, and the press-fitting is reliably performed.
[0025]
After the press-fitting of the objects 23 and 24 into the housings 11 and 12 is completed, if necessary, the end of the cylinder of each housing is subjected to drawing (for example, spinning) and deformed into a funnel shape. Then, the annular ends of the flange members 21 and 22 are abutted to each other, and the entire periphery is welded thereto, whereby the maniverter including the catalytic converter shown in FIG. 1A is completed.
[0026]
(Effect) According to the present embodiment, even when the converter case 10 has a bent shape having a bent portion 13 between the two substantially cylindrical housing portions 11 and 12, even if the converter case 10 and the installation surface P are bent. By interposing the shaft alignment jig, the converter case housing portion into which the object 23 or 24 is to be press-fitted can be set upright with respect to the installation surface P. Therefore, it becomes easy to align the object 23 or 24, which is press-fitted from the normal direction of the installation surface P, with the housing part 11 or 12 to be press-fitted, and the catalyst holder is placed in each housing part of the converter case. The contained object 23 or 24 can be smoothly and reliably press-fitted.
[0027]
Further, according to the catalytic converter manufactured by the present method, since the relatively small catalyst holders 23a and 24a are divided and arranged in series in the converter case 10, the exhaust gas fixed or supported by each holder is provided. The purification performance of the purification catalyst is improved. In addition, since the bent shape is provided with the bent portion 13 in the middle, there is a degree of freedom in selecting a shape according to the mounting space of the vehicle, and it is easy to reduce the size and space of the entire catalytic converter. Therefore, it is possible to avoid inconveniences such as difficulty in securing a mounting space at the time of mounting on a vehicle and waste of the exhaust pipes. And the degree of freedom in mounting the exhaust pipes connected before and after the catalytic converter can be improved.
[0028]
【The invention's effect】
According to the method for manufacturing a catalytic converter of the present invention, even when the converter case has a bent shape having a bent portion between two substantially cylindrical housing portions, it is press-fitted or pressed from the normal direction of the installation surface. Axis alignment between the object to be inserted and the accommodation part to be press-fitted or inserted is facilitated, and the object including the catalyst holding member is smoothly and reliably press-fitted or inserted into each accommodation part of the converter case. It is possible to do. Further, according to the shaft aligning jig of the present invention, the method for manufacturing the present catalytic converter can be smoothly and reliably performed.
[Brief description of the drawings]
1A is a schematic front view of a maniverter including a catalytic converter, and FIG. 1B is a cross-sectional view of a disassembled state of a converter case and a stored object.
2A is a plan view of an alignment jig, and FIG. 2B is a cross-sectional view taken along line XX.
FIGS. 3A and 3B are cross-sectional views illustrating a procedure for press-fitting an object to be stored.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Converter case, 11 ... Upstream accommodation part, 12 ... Downstream accommodation part, 13 ... Bent part, 23, 24 ... Contained object, 23a, 24a ... Catalyst holding body, 23b, 24b ... Holding sealing material, 31 ... Main body of the alignment jig, 32: receiving portion, 33: inclined mounting surface, 34: curved support surface, L1, L2: central axis, P: installation surface of the workbench.

Claims (3)

A method for manufacturing a catalytic converter, comprising: a converter case in which a bent portion is formed between two substantially cylindrical storage portions; and a storage object including a catalyst holder.
In addition to preparing an alignment jig having a mounting surface inclined with respect to the installation surface at the time of operation, the cylindrical end of one of the two storage portions of the converter case is inclined by the inclination of the alignment jig. By placing the remaining housing portion of the two housing portions substantially upright with respect to the installation surface by contacting and disposing it on the mounting surface, the catalyst holding portion is held in the upright housing portion. A method for manufacturing a catalytic converter, comprising inserting or inserting an object including a body from a direction normal to the installation surface. In the alignment jig, the inclination angle of the mounting surface with respect to the installation surface is set so as to substantially coincide with the intersection angle between the central axes (L1, L2) of the two housing portions of the converter case. The method for manufacturing a catalytic converter according to claim 1. A shaft alignment jig for use when press-fitting or inserting an object containing a catalyst holder into each of the accommodating portions of a catalytic converter case in which a bent portion is formed between two approximately cylindrical accommodating portions. ,
At the time of work, the jig main body installed on the installation surface is provided with a receiving portion for receiving the housing portion of the converter case, and the bottom of the receiving portion is inclined with respect to the installation surface, and A mounting surface for contacting the cylindrical end of the housing portion is formed, and an angle of inclination of the mounting surface with respect to the installation surface substantially coincides with an intersection angle between central axes of the two housing portions of the converter case. An alignment jig characterized by being set as follows.

Images