JP2007162583A - Seal member for catalytic converter, and catalytic converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal member for a catalytic converter, in which displacement in installation position of a seal member is prevented to stabilize sealing performance over a long period of time, while avoiding significant increase in cost and deterioration in resilience of a whole seal member, and to provide a catalytic converter. <P>SOLUTION: The degree of reinforcement by organic binder or needle punching at upstream end part and at a downstream end part in an exhaust gas flow direction in the seal member 4 for a catalytic converter is higher than that in other areas. Therefore, while the displacement caused by insertion resistance or the like in insertion of the seal member in a metallic shell, elasticity of the seal member 4 is maintained to maintain high retaining force of the seal member 4 by the resilience in other areas. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a seal member applied to, for example, a catalytic converter for purifying exhaust gas of an automobile, and a catalytic converter using the seal member. In particular, the present invention relates to measures for achieving long-term stabilization of the sealing performance of the sealing member.

  Conventionally, as disclosed in, for example, Patent Document 1 and Patent Document 2 below, in an automobile exhaust system, a catalytic converter that purifies exhaust gas components such as hydrocarbons, carbon monoxide, and nitrogen oxide in exhaust gas. Is provided.

  As shown in FIG. 1, this catalytic converter includes, for example, a ceramic catalyst carrier 2, a metal shell 3 that covers the outside thereof, and an inorganic material that is interposed between the catalyst carrier 2 and the metal shell 3. It is the structure provided with the sealing member 4 using this. The seal member 4 has a function of preventing exhaust gas from leaking between the catalyst carrier 2 and the metal shell 3. For example, silica / alumina ceramic fiber, unexpanded vermiculite, inorganic binder, A seal mat in which a mixture of organic elastic materials is formed into a sheet shape is used. Further, since the catalyst carrier 2 and the metal shell 3 have different thermal expansion coefficients, a difference in thermal expansion occurs at a high temperature. For this reason, the sealing member 4 is required to have a cushioning property that can absorb this difference in thermal expansion.

  By the way, in recent years, the temperature of exhaust gas tends to increase due to the high performance of automobiles and various laws and regulations, and if the heat resistance of the sealing member 4 is insufficient, the sealing performance is deteriorated. . In particular, when the mounting position of the seal member 4 is relatively displaced from the catalyst carrier 2 and a part (end portion) of the seal member 4 protrudes from the edge of the catalyst carrier 2, the seal of the seal member 4 is sealed. The performance will be extremely deteriorated. That is, in the protruding portion of the seal member 4, the silica / alumina ceramic fiber in the seal member 4 becomes brittle due to the heat of the exhaust gas, or the expansion characteristics of the unexpanded vermiculite deteriorate, and the exhaust gas A part of the seal member 4 is eroded by the pulse pressure, which causes deterioration of the seal performance of the seal member 4. Moreover, the holding area of the sealing member 4 decreases due to the protrusion of the sealing member 4, and the holding force of the sealing member 4 decreases accordingly, which also causes deterioration of the sealing performance. . The displacement of the mounting position of the seal member 4 is caused by an insertion resistance when the seal member 4 is inserted into the metal shell 3 with the seal member 4 wound around the outer periphery of the catalyst carrier 2. Further, this displacement of the mounting position also occurs due to the influence of the vehicle body vibration after insertion and the pressure of exhaust gas.

In order to eliminate such problems, for example, in Patent Document 3 below, it is proposed to form the exhaust gas inflow side end portions or the inflow side and outflow side ends of the seal member with an inorganic binder. .
JP 2001-259438 A JP 2003-97262 A JP-A-62-197717

  However, when an inorganic binder is applied to the end portion of the sealing member as disclosed in Patent Document 3, the hardness of the end portion of the sealing member becomes too high and lacks flexibility. It becomes difficult to be processed into a cylindrical shape due to the occurrence of breakage when the catalyst carrier is wound around the outer periphery.

  In order to eliminate this hardening, as disclosed in Patent Document 2, it is necessary to vacuum pack the inorganic binder with an airtight film in an undried state. A packing film is required as well as a protective film. For this reason, the manufacturing process of a sealing member will increase and cost will also rise.

  As a method for preventing the sealing member from being displaced from the catalyst carrier without using the inorganic binder, increasing the density of the sealing member and increasing the amount of the binder as a whole sealing member. In the needle punching process during the manufacturing process of the seal member, it is conceivable to set the density of the needle punching portion as high as the entire seal member. However, any of these methods is not preferable because it not only causes a significant increase in cost, but also reduces the rebound (elasticity) of the sealing member over the whole and reduces the holding force of the sealing member.

  The present invention has been made in view of such a point, and the object of the present invention is to avoid a situation in which the cost is significantly increased or the resilience of the seal member is reduced over the whole. It is another object of the present invention to provide a catalytic converter seal member and a catalytic converter which can prevent the mounting position of the seal member from being shifted and thereby stabilize the sealing performance for a long period of time.

-Principle of solving the problem-
The solution principle of the present invention devised to achieve the above object is that at least one of the upstream end portion and the downstream end portion in the exhaust gas flow direction in the catalytic converter seal member is set as another region. Compared with the organic binder or needle punching, the degree of reinforcement is increased. Thus, while avoiding a shift caused by an insertion resistance or the like when inserted into the shell, the elasticity of the seal member is maintained in the other region, and the holding force of the seal member due to the repulsive force can be maintained high. ing.

-Solution-
Specifically, the present invention is premised on a sealing member for a catalytic converter that is disposed between a catalyst carrier and a shell that covers the outer periphery of the catalyst carrier, and is constituted by impregnating a binder into inorganic fibers. . The catalytic converter seal member is impregnated with an organic binder at at least one of its upstream end and downstream end in the exhaust gas flow direction and its peripheral portion, and the organic binder at this end is impregnated. The impregnation amount is set to be larger than the binder impregnation amount in the central portion in the exhaust gas flow direction.

  Moreover, the following are also mentioned as another solution means for achieving said objective. That is, it is premised on a catalytic converter seal member that is disposed between a catalyst carrier and a shell that covers the outer periphery of the catalyst carrier and is formed by subjecting inorganic fibers to needle punching. The density of the needle punching process in at least one of the upstream end portion and the downstream end portion in the exhaust gas flow direction and the peripheral portion of the seal member for the catalytic converter is set at the center portion in the exhaust gas flow direction. The density is set higher than the density of the punching process.

  Due to these specific matters, only the end portion of the seal member is reinforced to be particularly high, and the displacement of the mounting position due to the deformation caused by the insertion resistance at the time of insertion into the shell is less likely to occur. Further, since the sealing member has a relatively low degree of reinforcement at the central portion in the exhaust gas flow direction and maintains high elasticity, the holding force due to the repulsive force accompanying this elasticity can be high. It has been. This also makes it difficult to shift the mounting position of the seal member. As a result, the sealing member can maintain high sealing performance over a long period of time. In addition, since the inorganic binder is not applied to the end of the seal member, the problem that the hardness of the end of the seal member becomes too high does not occur, and the conventional decompression pack using an airtight film becomes unnecessary. Further, the manufacturing of the sealing member can be facilitated and the manufacturing cost can be reduced.

  Further, in the case where the amount of impregnation of the organic binder at the end portion of the seal member is set larger than the amount of binder impregnation in the other portion (the central portion in the exhaust gas flow direction), the following is a more specific configuration Can be mentioned. First, the end of the shell in which the sealing amount for the catalytic converter is wound around the outer periphery of the catalyst carrier, with the end where the amount of impregnation of the organic binder is set larger than the amount of binder impregnation in the central portion in the exhaust gas flow direction. This is the end on the near side in the insertion direction when inserted inside. Further, the end portion where the organic binder impregnation amount is larger than the binder impregnation amount in the central portion in the exhaust gas flow direction is only the downstream end portion in the exhaust gas flow direction.

  In the case of the former configuration, it is possible to effectively avoid a shift caused by an insertion resistance or the like when inserted into the shell. In the case of the latter configuration, even if the amount of impregnation of the organic binder at the upstream end in the exhaust gas flow direction is set large, the organic binder may disappear due to the heat of the exhaust gas. This organic binder is applied to the downstream end in the exhaust gas flow direction to prevent the exhaust gas from disappearing due to heat.

  Also, in the case where the density of the needle punching process at the end of the seal member is set higher than the density of the needle punching process at the other part (the central part in the exhaust gas flow direction), the density of the needle punching process is the exhaust gas. The insertion direction before inserting the end portion set higher than the density of the needle punching process in the central portion in the flow direction into the shell with the catalytic converter seal member wound around the outer periphery of the catalyst carrier It is mentioned that it is set as the edge part of the side. Also in this case, it is possible to effectively avoid the deviation caused by the insertion resistance when inserted into the shell.

  The present invention also relates to a catalytic converter in which the sealing member according to any one of the above-described solving means is disposed between a catalyst carrier and a shell covering the outer periphery of the catalyst carrier. This is a category of technical ideas.

  In the present invention, at least one of the upstream end and the downstream end in the exhaust gas flow direction in the catalytic converter seal member has a higher degree of reinforcement than the other regions, so that the inside of the shell. It is possible to avoid a positional shift caused by insertion resistance at the time of insertion of the seal member, and also to maintain elasticity of the central portion of the seal member and to maintain a high holding force of the seal member due to the repulsive force. Misalignment can be avoided. As a result, long-term stabilization of the sealing performance of the sealing member can be achieved. Further, since an inorganic binder is not applied to the end of the seal member, the end portion of the seal member becomes too hard, or a decompression pack using an airtight film is necessary to prevent it. There is nothing to do. For this reason, the manufacture of the sealing member can be facilitated and the manufacturing cost can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment demonstrates the case where the catalytic converter which concerns on this invention is applied as a catalytic converter for exhaust-gas purification | cleaning provided in the exhaust system of a motor vehicle.

-Configuration of catalytic converter-
As shown in FIG. 1, the catalytic converter 1 according to the present embodiment includes a catalyst carrier 2 that supports a catalyst that purifies exhaust gas components, a metal shell 3 that covers the outer periphery of the catalyst carrier 2, and these catalysts. A seal member 4 made of an inorganic fiber mat disposed between the carrier 2 and the metal shell 3 is provided. That is, the catalytic converter 1 is produced by inserting the seal member 4 around the outer periphery of the catalyst carrier 2 and inserting the seal member 4 into the metal shell 3. And the metal shell 3 are prevented from leaking exhaust gas.

  The sealing member 4 has a structure in which one or more fibrous materials selected from alumina, silica / alumina, glass, and silica are used as a base material, and an organic material (organic binder) is combined (impregnated) with the base material. ing. Specifically, the content of the organic component in the seal member 4 is, for example, 2 to 8% by mass. The inorganic fiber mat constituting the seal member 4 is made of, for example, 70% by mass of alumina and 30% by mass of silica, and is molded by performing a needle punching process, which will be described later, and a binder process using an organic binder.

The filling density of the sealing member 4 in the metal shell 3 is adjusted to be, for example, 0.15 to 0.5 g / cm ³ . This is because if the packing density is less than 0.15 g / cm ³ , a predetermined holding force cannot be obtained and the positions of the seal member 4 and the catalyst carrier 2 may be shifted. On the other hand, if the packing density is larger than 0.5 g / cm ³ , there is a risk that the insertion operation into the metal shell 3 becomes difficult, or the compressive stress after assembly becomes high and the inorganic fiber breaks and scatters. . The above numerical values are not limited to this and can be arbitrarily set.

  The catalyst carrier 2 has a honeycomb structure manufactured from cordierite, alumina, or the like, which is a kind of ceramic. That is, as shown in FIG. 1, the catalyst carrier 2 is an aggregate of cells that are open on the upstream side of the exhaust pipe and closed on the downstream side, and conversely, cells that are closed on the upstream side of the exhaust pipe and open on the downstream side. A honeycomb structure made of A large number of micropores are opened in the cell wall, and a catalyst (for example, platinum, rhodium, etc.) for purifying exhaust gas components is attached to the cell wall. Therefore, when the exhaust gas passes through the cell wall from the cell opened on the upstream side to the cell opened on the downstream side, the catalyst carrier 2 contains the exhaust gas contained in the exhaust gas by the catalytic action carried on the cell wall. It becomes the composition in which a component is purified.

  As the metal shell 3, a stainless steel cylinder having a circular or oval cross section is used.

  As a feature of the present embodiment, the sealing member 4 is impregnated with an organic binder around the upstream end in the exhaust gas flow direction and around the downstream end, and the organic binder at these ends. Is set to be larger than the binder impregnation amount in the central portion in the exhaust gas flow direction. Further, the seal member 4 is set such that the density of the needle punching process in the vicinity of the upstream end in the exhaust gas flow direction and the vicinity of the downstream end is higher than the density of the needle punching process in the central part in the exhaust gas flow direction. Has been. That is, the seal member 4 is reinforced at the periphery of the upstream end portion in the exhaust gas flow direction and the periphery of the downstream end portion higher than the other portions, while having high elasticity at the central portion in the exhaust gas flow direction. The configuration is maintained.

-Manufacturing method of catalytic converter-
Next, a manufacturing method of the sealing member 4 having the above-described configuration, an apparatus for manufacturing the sealing member 4, and manufacturing of the catalytic converter 1 in which the manufactured sealing member 4 is assembled to the metal shell 3 together with the catalyst carrier 2. A method will be described.

  Here, as a method for manufacturing the seal member 4, a case where twelve seal members 4, 4,... Are cut out from one web formed by laminating inorganic fibers in a plurality of layers (multiple pieces are taken) will be described. . Specifically, as shown in FIG. 8, locations corresponding to the periphery of the upstream end portion and the periphery of the downstream end portion of each seal member 4 in the exhaust gas flow direction with respect to one web W <b> 5. 12 in total in a lateral direction (width direction of the web W5) and 4 in the longitudinal direction (longitudinal direction of the web W5) in a state of being reinforced particularly highly by impregnation with an organic binder or needle punching treatment 4, 4, ... are cut out. The number of seal members 4, 4,... Cut out from this one web W5 can be arbitrarily set.

  The manufacturing process of the sealing member 4 includes a needle punching process in which the laminated inorganic fibers are needle punched, and a binder process in which an organic binder is combined (impregnated) on the web. Hereinafter, each step will be described.

(Needle punching process)
First, inorganic fibers composed of 70% by mass of alumina and 30% by mass of silica are laminated in a plurality of layers to form a web W1 having a rectangular shape in plan view. Then, as shown in FIG. 2 (process drawing in which a part of the web is omitted), the first needle punching device 5 and the second needle installed on the conveyance path while conveying the web W1 on the conveyor C. A two-stage needle punching process is sequentially performed by the punching device 6. Hereinafter, the needle punching devices 5 and 6 will be described.

  The first needle punching device 5 receives a driving force in the vertical direction from a driving source, as shown in FIG. 3 (cross-sectional view seen from the direction along the conveying direction of the web W1; the web W1 is indicated by an imaginary line). A needle board 51 that can reciprocate in the needle piercing direction (vertical direction), and a pair of support plates 52 and 53 that face both the front and back surfaces of the web W1. The support plates 52 and 53 are formed with needle insertion openings 52a and 53a, respectively.

  A large number of needles 54, 54,... For piercing the web W1 are fixed to the lower surface of the needle board 51. In the vicinity of the tip of each needle 54, 54,..., A “return” for hooking a part of the inorganic fibers when pierced by the web W 1 is formed. In the first needle punching device 5, these needles 54, 54,... Are arranged at equal intervals in the horizontal direction orthogonal to the conveying direction of the web W1. In addition, a plurality of sets of needle rows that are arranged at equal intervals in the horizontal direction orthogonal to the conveyance direction of the web W1 may be arranged across the conveyance direction of the web W1.

  In the needle punching process by the first needle punching device 5, the web W1 is passed between the support plates 52 and 53, and the needle board 51 is reciprocated in the vertical direction, whereby the needles 54 and 54 are moved to the web W1. ,... Are pierced and entangled between the fibers in the web W1. That is, the needle punching operation of piercing each needle 54, 54,... Into the web W1 by the lowering of the needle board 51 (lowering to the position shown in FIG. 3), and after the needle board 51 moves up, the web W1 is moved by a predetermined distance. By alternately repeating the web feeding operation, the needle punching process is uniformly performed over the entire web W1, and the inorganic fiber mat (web W2) is formed into a rectangular shape. The feed amount per web feed operation at this time coincides with the interval (needle pitch) between the needles 54 and 54, for example.

  The web W2 formed in this way is partially reinforced by the second needle punching device 6. This second needle punching device 6 is the same as the first needle punching device 5 as shown in FIG. 4 (cross-sectional view seen from the direction along the web W2 conveyance direction: the web W2 is shown in phantom). Further, a needle board 61 capable of reciprocating in the needle piercing direction (vertical direction) and a pair of support plates 62 and 63 facing both the front and back surfaces of the web W2 are provided. The support plates 62 and 63 are also formed with needle insertion openings 62a and 63a, respectively.

  A large number of needles 64, 64,... For piercing the web W2 are fixed to the lower surface of the needle board 61. As a feature of the second needle punching device 6, these needles 64, 64,... Are arranged at unequal intervals. Specifically, each of the 12 sealing members 4, 4,... Cut out from one web (the upstream edge and the downstream in the exhaust gas flow direction when assembled to the catalytic converter 1) Only a part of the needles 64 and 64 so that the needle punching process at a density higher than the density of the needle punching process performed by the first needle punching device 5 is performed only on the end part) and its peripheral part. Are arranged. Further, specifically, the portion indicated by the region A in FIG. 8 is a portion that becomes the periphery of the upstream end portion and the periphery of the downstream end portion in the exhaust gas flow direction in each of the sealing members 4, 4,. A distance (for example, 1) shorter than the distance (needle pitch) between the needles in the first needle punching device 5 is opposed to this portion so that the needle punching process at a high density is performed only on this portion. / 3), the needles 64, 64,... Are arranged. In addition, a plurality of sets of needle rows arranged in the horizontal direction orthogonal to the conveyance direction of the web W2 may be arranged over the conveyance direction of the web W2.

  In the needle punching process by the second needle punching device 6, the web W2 is passed between the support plates 62 and 63 and the needle board 61 is reciprocated in the vertical direction, whereby the needles 64 and 64 are moved to the web W2. ,... Are pierced and entanglement is partially formed between the fibers in the web W2. That is, the needle punching operation of piercing each needle 64, 64,... Into the web W2 by the lowering of the needle board 61 (lowering to the position shown in FIG. 4), and after the needle board 61 has moved up, the web W2 is moved by a predetermined distance. By alternately repeating the web feeding operation to be conveyed, the web W3 in which only the portion corresponding to the end edge of the seal member 4 is further reinforced is formed. At this time, the feed amount per one web feed operation is set smaller than the feed amount in the needle punching process of the first needle punching device 5 (for example, a feed amount of 1/3). The needle punching process at is performed.

  2, 5, and 8, the sizes of the needle punching marks by the needle punching process performed by the first needle punching device 5 and the needle punching marks by the needle punching process performed by the second needle punching device 6 are shown. It is easy to understand that the density of each needle punching process is different. When the needles 54 and 64 used in the needle punching devices 5 and 6 have the same diameter, these needle punching marks have the same size.

  After the web W3 formed as described above is fired, the process proceeds to a binder process as the next process.

(Binder process)
In this binder process, as shown in FIG. 5 (process diagram in which a part of the web is omitted), the first binder device 7 and the second binder apparatus 2 installed on the transport path are transported while the web W3 is transported on the conveyor C. Two-stage binder processing (organic binder coating processing) is sequentially performed by the binder device 8. Hereinafter, the binder devices 7 and 8 will be described.

  As shown in FIG. 6 (a cross-sectional view seen from the direction along the conveyance direction of the web W3), the first binder device 7 scatters a liquid organic binder (latex solution such as rubber latex) from above the web W3. A plurality of (three in the present embodiment) binder showers 71, 71, 71 are provided. These binder showers 71, 71, 71 are configured to diffuse and release the organic binder so that the organic binder is evenly scattered over the entire web W3.

  That is, in the binder processing by the first binder device 7, the liquid W binder is scattered from each binder shower 71, 71, 71 to the web W 3 while continuously transporting the web W 3, so that the entire web W 3 is organic. A web W4 reinforced evenly by the binder is formed. 5 and 8, the region (entire surface) where the organic binder is applied by the binder processing by the first binder device 7 is hatched (the oblique line inclined upward in the right direction in the drawing).

  The web W 4 thus formed is partially reinforced by the second binder device 8. As shown in FIG. 7 (a cross-sectional view seen from the direction along the conveyance direction of the web W4), the second binder device 8 has a plurality of (only a part of the web W4 that scatters a liquid organic binder from above (see FIG. 7). In the present embodiment, four binder showers 81, 81,... Are provided. Specifically, each of the 12 sealing members 4, 4,... Cut out from one web (the upstream edge and the downstream in the exhaust gas flow direction when assembled to the catalytic converter 1) Binder showers 81, 81,... Are disposed so as to face the target portion so that the organic binder is additionally applied only to the end portion and its peripheral portion. More specifically, binder showers 81, 81,... Are arranged so as to face the target portion so that the organic binder is additionally applied only to the portion indicated by region A in FIG. . Further, in the second binder device 8 of the present embodiment, a masking plate 82 is provided so as to cover other than the area A so that the organic binder is surely applied only to the area indicated by the area A. ing. That is, the masking plate 82 is formed with openings 83, 83,... Only in the portion corresponding to the region A, and the organic binder is applied only to each end edge portion and its peripheral portion of the seal member 4. It is sure to be additionally applied.

  In the binder processing by the second binder device 8, the liquid organic binder is scattered on the web W4 from each of the binder showers 81, 81,... While continuously transporting the web W4, and then the web W4 is dried. As a result, the web W5 in which only a part of the web W4 (each end edge portion and its peripheral portion of the seal member 4) is reinforced by the organic binder is formed. In FIGS. 5 and 8, the region where the organic binder is applied by the binder processing by the second binder device 8 is hatched (the oblique line inclined upward in the left direction in the drawing).

  One web W5 (see FIG. 8) partially reinforced by the above needle punching process and binder process is obtained. By cutting the web W5 into a predetermined shape, twelve seal members 4, 4,. Cut out. Each of the seal members 4, 4,... Cut out in this manner is a portion that becomes an upstream end and a downstream end in the exhaust gas flow direction when assembled to the catalytic converter 1 and its peripheral portion (seal member). The upper and lower end edges extending in the longitudinal direction of 4 are particularly reinforced. In this cutting operation, each cutting position is reinforced by the needle punching step and the binder step, so that the cutting operation is easy.

(Catalytic converter manufacturing process)
Next, the manufacturing process of the catalytic converter 1 in which the seal member 4 is assembled to the metal shell 3 together with the catalyst carrier 2 will be described.

  As shown in FIG. 9A, the seal member 4 is formed with a concave portion 41 on one of the end edges on both sides in the longitudinal direction and a convex portion 42 having the same shape as the concave portion 41 on the other side. As shown in FIG. 9B, the seal member 4 is wound around the outer periphery of the catalyst carrier 2 to engage the concave portion 41 and the convex portion 42. At this time, the positions of both end portions in the axial direction of the cylindrical seal member 4 are made to coincide with the positions of both end surfaces of the catalyst carrier 2. That is, the edge of the catalyst carrier 2 and the edge of the seal member 4 are flush with each other. Next, the catalyst carrier 2 around which the seal member 4 is wound is mounted in the cylindrical metal shell 3. As a result, the catalytic converter 1 shown in FIG. 9C is manufactured.

-Effect of the embodiment-
As described above, in the present embodiment, the upstream end and the downstream end in the exhaust gas flow direction of the seal member 4 have a higher degree of reinforcement than the other regions, so that the metal shell 3 is brought into the interior. It is possible to avoid misalignment caused by the insertion resistance at the time of insertion. Further, since the density of the needle punching process is lowered and the amount of impregnation of the organic binder is reduced in the central portion of the seal member 4, the elasticity can be maintained, and the holding force of the seal member 4 due to the repulsive force is increased. Can be maintained. Also by this, the position shift of the sealing member 4 inside the metal shell 3 can be avoided. As a result, it is possible to stabilize the sealing performance of the sealing member 4 for a long period of time.

  In particular, when a process for increasing the coefficient of friction of the inner surface of the metal shell 3 (rough surface process) is performed in order to prevent the displacement of the seal member 4 with respect to the metal shell 3, the seal member 4 is wound around the catalyst carrier 2. In such a state, it becomes difficult to insert the seal member 4 into the metal shell 3, and the seal member 4 is likely to be displaced due to the insertion resistance. However, as in this embodiment, the end of the seal member 4 is reinforced. If the height is set high, the insertion operation can be completed without incurring a positional shift.

  Further, since an inorganic binder is not applied to the end portion of the seal member 4, the end portion of the seal member 4 becomes too hard, and a decompression pack using an airtight film is necessary to prevent it. It does not become. For this reason, manufacture of the sealing member 4 can be facilitated and the manufacturing cost can be reduced.

-Modification-
In the embodiment described above, the two-stage needle punching process by the first needle punching device 5 and the second needle punching device 6 is sequentially performed as the needle punching process. In this modification, this needle punching step is performed by a single needle punching device.

  FIG. 10 is a needle punching device 9 (cross-sectional view as seen from the direction along the conveyance direction of the web W1; the web W1 is shown by phantom lines) in the present modification. As shown in FIG. 10, the needle punching device 9 in the present modification example receives the driving force in the vertical direction from the driving source in the needle piercing direction (vertical direction) in the same manner as the needle punching devices 5 and 6 in the above-described embodiment. A needle board 91 capable of reciprocating in the direction) and a pair of support plates 92 and 93 facing both the front and back surfaces of the web W1.

  The needle punching device 9 is characterized by an array of needles 94, 94,... Fixed to the lower surface of the needle board 91. That is, the arrangement of the needles 94, 94,... In the present modification is the same as the arrangement of the needles 54, 54,... In the first needle punching apparatus 5 and the needles 64, 64,. Are combined with each other in the needle punching process over the entire web W1 and twelve sealing members 4, 4,... Cut out from the one web W5. Simultaneously with a partial needle punching process for reinforcing the end edge portion (the upstream end portion and the downstream end portion in the exhaust gas flow direction when assembled to the catalytic converter 1) and its peripheral portion It can be executed.

  As described above, in this modification, the needle punching process for the entire web W1 and the needle punching process for performing partial reinforcement can be simultaneously performed by one piercing operation. A stand is sufficient, and the production line and production time of the seal member 4 can be shortened.

  Although not shown, a binder device that combines the arrangement of the binder showers 71, 71, 71 in the first binder device 7 and the arrangement of the binder showers 81, 81,... In the second binder device 8 in the above-described embodiment. In the case of construction, since the binder processing over the entire web W3 and the binder processing for performing partial reinforcement can be performed simultaneously by one scattering operation of the organic binder, one binder device is used. This also shortens the production line and production time of the seal member 4.

-Other embodiments-
In the embodiment and the modification described above, the seal member 4 has other portions on the periphery of the upstream end in the exhaust gas flow direction and on both sides of the periphery of the downstream end by needle punching and organic binder impregnation. It was set as the structure reinforced higher than. The present invention is not limited to this, and only one of the periphery of the upstream end and the periphery of the downstream end in the exhaust gas flow direction is reinforced higher than the other portions by the needle punching process and the organic binder impregnation process. It is good also as the structure currently made. Further, as means for reinforcing each part, both the needle punching process and the organic binder impregnation process may be performed, or only one of them may be performed. As an example, in the case where the seal member 4 is wound around the outer periphery of the catalyst carrier 2 and inserted into the metal shell 3 from the upstream side of the exhaust gas flow, needle punching treatment and For example, the sealing member 4 may be reinforced by both the impregnation treatment of the organic binder, and the sealing member 4 may be reinforced only by the needle punching treatment at the upstream end of the exhaust gas flow.

  In addition, the needle punching process and the organic binder impregnation process are performed on each of the seal members 4, 4,... After cutting out the plurality of seal members 4, 4,. May be. Further, the entire uniform reinforcing operation is performed before cutting out the seal members 4, 4,..., And the partial reinforcing operation (the periphery of the upstream end and the downstream end of the seal member 4 in the exhaust gas flow direction) is performed. May be performed after the sealing members 4, 4,... Are cut out. In this case, as the impregnation treatment of the organic binder, an operation of immersing only the edge portion of the seal member 4 in the organic binder stored in the container is possible.

  Further, in the binder process, a difference is made in the degree of reinforcement at each place by varying the coating amount (scattering amount) of the organic binder with respect to the web W3. The present invention is not limited to this, and the difference in the degree of reinforcement may be caused by varying the concentration of the organic binder for each part of the web W3.

It is sectional drawing of a catalytic converter. It is process drawing for demonstrating a needle punching process. It is sectional drawing which shows a 1st needle punching apparatus. It is sectional drawing which shows a 2nd needle punching apparatus. It is process drawing for demonstrating a binder process. It is a figure which shows the binder process operation | movement by a 1st binder apparatus. It is a figure which shows the binder process operation | movement by a 2nd binder apparatus. It is a web top view for demonstrating the cutting-out operation | movement of the sealing member from a web. It is a figure for demonstrating a catalytic converter manufacturing process. It is sectional drawing which shows the needle punching apparatus which concerns on a modification.

Explanation of symbols

1 catalytic converter 2 catalyst carrier 3 metal shell 4 sealing member

Claims (6)

In a seal member for a catalytic converter that is disposed between a catalyst carrier and a shell that covers the outer periphery of the catalyst carrier, and is configured by impregnating a binder with inorganic fibers.
At least one of the upstream end and the downstream end in the exhaust gas flow direction and its peripheral part are impregnated with an organic binder, and the amount of the organic binder impregnated at this end is the exhaust gas flow direction. A catalytic converter seal member, characterized in that it is configured to have a larger amount than the amount of binder impregnation in the central portion of the catalyst converter. In a seal member for a catalytic converter that is disposed between a catalyst carrier and a shell that covers the outer periphery of the catalyst carrier, and is configured by subjecting inorganic fibers to needle punching treatment,
The density of the needle punching process in at least one of the upstream end and the downstream end in the exhaust gas flow direction and its peripheral part is set higher than the density of the needle punching process in the central part in the exhaust gas flow direction. A sealing member for a catalytic converter, characterized in that it is configured as described above. The sealing member for a catalytic converter according to claim 1,
The end where the amount of impregnation of the organic binder is set larger than the amount of binder impregnation in the central portion in the exhaust gas flow direction is placed inside the shell with the catalytic converter seal member wound around the outer periphery of the catalyst carrier. A seal member for a catalytic converter, which is an end portion on the near side in the insertion direction when inserted. The sealing member for a catalytic converter according to claim 2,
The end where the density of the needle punching process is set higher than the density of the needle punching process in the central portion in the exhaust gas flow direction is the inside of the shell with the sealing member for the catalytic converter wound around the outer periphery of the catalyst carrier. A catalytic converter seal member, characterized in that it is an end portion on the near side in the insertion direction when inserted into the catalytic converter. The sealing member for a catalytic converter according to claim 1,
The catalytic converter sealing member characterized in that the end portion where the organic binder impregnation amount is larger than the binder impregnation amount in the central portion in the exhaust gas flow direction is only the downstream end portion in the exhaust gas flow direction .   A catalyst characterized in that the seal member according to any one of claims 1 to 5 is disposed between a catalyst carrier and a shell covering the outer periphery of the catalyst carrier. converter.

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