JP6711729B2 - Catalytic metal carrier - Google Patents

Description

The present invention relates to catalytic metal supports.

BACKGROUND ART Conventionally, there are catalyst metal carriers described in Patent Documents 1 and 2 as a catalyst metal carrier for purifying exhaust gas discharged from an internal combustion engine such as an automobile engine.

The catalyst metal carrier for an automobile engine described in Patent Document 1 is a cylindrical stainless steel metal foil (foil) in which a plurality of concave portions are continuously formed in the circumferential direction on the inner peripheral surface of a stainless steel cylindrical case. The thickness is about 200 μm) and is brazed. As a result, a large number of small exhaust passages partitioned by the cylindrical metal foil are defined inside the exhaust passage formed by the tubular case. Then, the catalyst is applied and baked and carried on the inner peripheral surface of the cylindrical case and the surface of the metal foil that defines the small exhaust passage.

The catalyst metal carrier for an automobile engine described in Patent Document 2 has a plurality of metal honeycomb bodies spaced apart from each other inside a tubular case made of stainless steel, and a tube-shaped body and/or a plate-shaped body between the metal honeycomb bodies. The body is arranged, and the metal honeycomb body, the tube-shaped body and/or the plate-shaped body are brazed to the inner peripheral surface of the tubular case. The metal honeycomb body is composed of a flat foil and a corrugated foil made of metal such as stainless steel. As a result, a large number of small exhaust passages formed of small holes of the metal honeycomb body are formed inside the exhaust passage formed by the tubular case, and the small exhaust passages are partitioned by the tube-shaped body and/or the plate-shaped body. Partition. The catalyst is coated on the inner peripheral surface of the cylindrical case, the inner surface of the small holes of the metal honeycomb body that defines the small exhaust passage, and the surface of the tube-shaped body and/or plate-shaped body. To be done.

JP 2001-129407 A JP 2008-142682 A

The catalyst metal carrier described in Patent Document 1 has the following problems.
(1) A cylindrical metal foil is brazed to the inner peripheral surface of the cylindrical case.
When the temperature of the exhaust gas reaches a temperature higher than the melting point of the brazing material (for example, about 1050° C.) during high-load operation of the automobile engine, the brazing material melts and the cylindrical metal foil cannot be fixed to the tubular case.

Also, when a large thermal stress is generated between the metal foil distorted by the exhaust gas heated to a high temperature due to the high load operation of the automobile engine and the cylindrical case under air cooling, or when the vibration of the automobile body and engine becomes severe, these heat Stress and severe vibration destroy the metal foil, making it impossible to fix the cylindrical metal foil to the cylindrical case.

The catalyst metal carrier described in Patent Document 2 has the following problems.
(2) A metal honeycomb body, a tube-shaped body and/or a plate-shaped body are brazed to the inner peripheral surface of the tubular case.

When the exhaust gas temperature becomes higher than the melting point of the brazing material (for example, about 1050°C) during high-load operation of the automobile engine, the brazing material melts and the metal honeycomb body, the tube-shaped body and/or the plate-shaped body is formed into a cylinder. Cannot be fixed to the case.

Further, when a large thermal stress is generated between the metal honeycomb body distorted by the exhaust gas heated to a high temperature due to the high load operation of the automobile engine and the tubular case under air cooling, or when the vibration of the vehicle body and the engine of the automobile becomes severe, these Thermal stress and severe vibration destroy the metal honeycomb body, and the metal honeycomb body cannot be fixed to the tubular case.

When the catalyst metal carrier described in Patent Documents 1 and 2 is used in a harsh driving environment of an automobile, such as an automobile race competition, the exhaust gas temperature rises and the vibration of the vehicle body and the engine increase significantly, The problems (1) and (2) above become more prominent.

Even if the brazing part used in the catalyst metal carrier described in Patent Documents 1 and 2 is replaced with a welded part such as spot welding, under the severe driving environment of an automobile, high temperature exhaust gas is generated. It is not possible to avoid destruction of the metal foil or the metal honeycomb body due to the resulting thermal stress or severe vibration of the vehicle body and engine.

In particular, under harsh driving conditions such as car racing competition, unburned gas has an inner peripheral surface of a cylindrical case in a catalyst metal carrier, a cylindrical metal foil, a metal honeycomb body, a tube-shaped body and/or a plate-shaped body. After attaching to the body to cause afterfire, the cylindrical metal foil, the metal honeycomb body, the tube-shaped body and/or the plate-shaped body is exposed to exhaust gas of higher temperature and pressure.

Then, in the catalyst metal carrier described in Patent Documents 1 and 2, when the cylindrical metal foil, the metal honeycomb body, the tube-shaped body and/or the plate-shaped body cannot be fixed to the cylindrical case, those cylindrical shapes The metal foil or metal honeycomb body, tube-shaped body and/or plate-shaped body of the above not only falls off the cylindrical case and loses the purification performance, but also scatters on the road and interferes with the safe running of the following vehicle. However, there is a risk that the race will be interrupted.

An object of the present invention is to provide a catalyst metal carrier capable of ensuring high durability under a severe environment of use.

The invention according to claim 1 is a catalyst metal carrier in which a metal fin forming body is arranged inside an exhaust passage formed by a cylindrical case, and the fin forming body has a large number of plate-shaped fins. Then, each fin extends in the exhaust passage so as to intersect the inner peripheral surface of the tubular case in the plate longitudinal direction, and a large number of small exhaust passages are defined in the exhaust passage by the adjacent fins, In a state in which the retaining means for preventing the fin forming body from falling out of the cylindrical case holds the fin forming body in the cylinder axis direction of the cylindrical case without being joined to the fins of the fin forming body, The fin forming body has a detent shaft coupled to the fin forming body in a detent state in the circumferential direction of the fin forming body at the center of the fin forming body, and the detent shaft includes: The retaining means is fixed to the retaining means supported by the cylindrical case in a rotation-preventing state.

The invention according to claim 2 is the invention according to claim 1, further comprising a plurality of fins formed inside the tubular case, the fins being sequentially arranged from one end side along the exhaust passage of the tubular case toward the other end side. The body is arranged.

The invention according to claim 3 is the invention according to claim 1 or 2, wherein the fin-forming body is formed of an integral body in which a large number of plate-shaped fins are machined to form one body. is there. The catalyst metal carrier according to claim 1 or 2.

According to a fourth aspect of the present invention, in addition to the first or second aspect of the present invention, the fin forming body is a plate assembly in which a plurality of metal plates are combined.

(Claim 1)
(a) A retaining means for preventing the fin forming body from falling out of the cylindrical case is supported by the cylindrical case and holds the fin forming body in the cylinder axis direction of the cylindrical case. Further, the whirl-stop shaft coupled to the central portion of the fin-forming body is fixed in the whirl-stop state to the above-mentioned retaining means supported by the tubular case. Therefore, the fin forming body is prevented from rotating inside the tubular case and is held in the tubular axis direction of the tubular case to prevent the fin forming body from falling out of the tubular case.

(b) The fin-forming body is exposed to the above-mentioned high-temperature exhaust gas even under a severe use environment of an automobile engine, even under a long-term continuous use environment where the exhaust gas temperature becomes a high temperature of, for example, about 1000°C to 1200°C due to high load operation. It is not fixed to the cylindrical case by using a brazing part that melts and melts. That is, the fin forming body is stably held in the cylindrical case by the above-described rotation prevention structure and retaining structure, which does not cause destruction even when exposed to high temperature exhaust gas, and the fin formation body is stably held in the cylindrical case. Can be retained.

(c) Even when the vibration of the vehicle body and engine of the automobile becomes severe, the fin forming body is stably held in the tubular case by the above-described rotation preventing structure and retaining structure, and the fin forming body is kept in the cylindrical case. Can be held stably.

(d) The retaining means is not joined to the fins of the fin-forming body and retains the fin-forming body so as to reliably prevent the fin-forming body from falling out. Here, the retaining means can restrain the deformation of each fin in the plate longitudinal direction by the engagement with the retaining means, as compared with the case where the retaining means is fixed to each fin of the fin forming body by welding or the like. Absent. As a result, the fin-forming body removes large thermal stress due to this thermal strain without being prevented by the presence of the retaining means for preventing thermal strain in the plate longitudinal direction of each fin due to exposure to high-temperature exhaust gas. It does not occur between the retaining means and is stably held by the retaining means.

(e) The fin forming body is prevented from rotating inside the cylindrical case through the engagement structure of the rotation preventing shaft provided in the central portion and the rotation preventing hole provided in the retaining means. As a result, it is not necessary to provide a fixing structure such as a welded portion, an engaging portion, a caulking portion, etc. for preventing rotation from being provided between the inner peripheral surface of the tubular case and the outer peripheral side of the fin forming body. It becomes a thing. Therefore, even if each fin of the fin forming body exposed to high-temperature exhaust gas inside the exhaust passage in the tubular case thermally expands toward the outer end along the plate longitudinal direction, it is the outer end of each fin. Due to the above-mentioned thermal expansion and vibration extending to the outer peripheral portion of the fin forming body, there is no possibility of causing damage or deformation of the fixing structure thereof. Even if the outer peripheral portion of the fin forming body that does not have the fixing structure may simply increase the pressure contact state between the outer peripheral portion and the inner peripheral surface of the cylindrical case due to the above-mentioned thermal expansion, It does not generate a large thermal stress between the inner peripheral surface and the inner peripheral surface of the steel sheet, which may cause destruction due to the thermal strain. That is, the fin forming body is stably held in the cylindrical case.

Temporarily, a detent portion is provided on the outer peripheral side of the fin forming body, and an anti-rotation structure such as an engaging portion and a caulking portion for detenting the detent portion is provided between the inner peripheral surface of the cylindrical case. When present, the thermal expansion of the fin-forming body is caused by the large temperature difference between the fin-forming body exposed to the high-temperature exhaust gas inside the exhaust passage and the cylindrical case that is air-cooled facing the external space. Is larger than that of the tubular case, the fins of the fin-forming body are constrained by the tubular case and a large thermal strain occurs. This thermal strain thermally deforms and damages the anti-rotation structure such as the engagement part and the caulking part existing between the outer peripheral part of the fin forming body and the inner peripheral surface of the tubular case, and the fin forming body There is a risk that the stopper will fall out of the rotation preventing structure between the stopper and the cylindrical case.

In the present invention, the fin forming body has the rotation preventing shaft at the center thereof, and the rotation preventing shaft is fixed in the rotation preventing hole provided in the retaining means in the rotation preventing state. None of the members are heated by contacting only the high-temperature exhaust gas inside the exhaust passage without being cooled by the outside air, and all the members thermally expand in a state of being evenly equal to each other. Thermal distortion is small. Further, even if the thermal expansion toward the outer end along the longitudinal direction of each fin in the fin forming body is restrained by the presence of the cylindrical case, the thermal expansion does not occur inside the fin forming body (the fin forming body). Only toward the center) of the fin forming body, and the detent shaft at the center of the fin forming body is compressed toward the center of the fin forming body to further restrain the detent shaft. Therefore, the fin forming body can be stably held inside the cylindrical case.

(f) In addition, the fin-formed body may be provided with a bent portion for absorbing thermal strain at an intermediate portion of each fin in the plate longitudinal direction.

In this case, the thermal strain of each fin in the fin forming body that is exposed to the high-temperature exhaust gas is absorbed by the thermal deformation of the bent portion provided in the intermediate portion of the fin, making it difficult to reach the cylindrical case. Since a large thermal stress is not generated in the tubular case and the tubular case is not destroyed, the fin forming body can be stably held in the tubular case.

Further, the destruction of the fin-formation body caused by the vibration caused by the violent vibration of the vehicle body is avoided by increasing the strength of the fin-formation body 20 by setting the plate thickness of the fin to a large thickness, for example, 0.8 to 3 mm. Therefore, the fin forming body can be stably held in the cylindrical case.

As described in (d) above, the structure that does not restrain the deformation of each fin of the fin forming body in the plate longitudinal direction is the absorption of the thermal strain of each fin by the bent portion provided in each fin of (f) above. It has the effect of not inhibiting the effect.

(Claim 2)
(g) Inside the tubular case, a plurality of fin forming bodies arranged in order from one end side to the other end side along the exhaust passage of the tubular case are arranged. The inner peripheral area over the entire length of the tubular case supporting the catalyst and the total surface area of all fin-forming bodies can be increased, and the purification performance of the catalyst metal carrier can be improved.

(Claim 3)
(h) The fin-forming body is made of an integrated body in which a large number of plate-shaped fins are machined so as to form an integral body, so that each fin has, for example, a plate thickness of 0.8 to 3 mm, and more preferably With a plate shape of 1 to 2 mm, the heat resistance strength and vibration resistance strength of the fin-formed body can be secured, and the durability of the catalyst metal carrier can be easily secured.

(Claim 4)
(i) By forming the fin-formed body from a plate assembly in which a plurality of metal plates are combined, each fin has a plate shape with a plate thickness of 0.8 to 3 mm, and more preferably 1 to 2 mm. The heat resistance strength and vibration resistance strength of the fin-formed body can be secured, and the durability of the catalyst metal carrier can be easily secured.

FIG. 1 is a front view showing a catalyst metal carrier according to the first embodiment. FIG. 2 shows a catalyst metal carrier, (A) is a sectional view taken along the line II-II of FIG. 1, and (B) is a sectional view showing a modification thereof. FIG. 3 shows a cylindrical case, (A) is a front view and (B) is a side view. FIG. 4 shows a fin-formed body, (A) is a front view of one fin-formed body that is aligned, (B) is a front view of the other fin-formed body that is aligned, and (C) is a stack of both fin-formed bodies. The front view which shows the state which carried out, (D) is a schematic diagram which shows the modification of a fin. FIG. 5 is a front view showing the retaining member. FIG. 6 shows a detent shaft, (A) is a side view and (B) is an end view. FIG. 7 shows a center cap, (A) is a front view, (B) is a side view, and (C) is a sectional view. FIG. 8 is a front view showing a modified example of the catalyst metal carrier. FIG. 9 is a front view showing a modified example of the fin body.

The catalytic metal carrier 1 shown in FIG. 1 and FIG. 2 is used by being connected to the outlet end portion (which may be the intermediate portion) of an exhaust pipe communicating with an exhaust port of an automobile engine. In the catalyst metal carrier 1, a metal fin forming body 20 is arranged inside an exhaust passage 11 formed by a cylindrical case 10 such as a cylinder, and the surface of a large number of plate-like fins 21 included in the fin forming body 20. It is constituted by supporting a catalyst on.

The catalyst metal carrier 1 is repeatedly heated and cooled each time the engine speed increases and decreases, and the cylindrical case 10 under air cooling and each fin 21 of the fin forming body 20 exposed to exhaust gas are in a severe thermal environment. .. When the catalyst metal carrier 1 is used in a severe long-term continuous use environment of an automobile engine, each fin 21 forming the fin forming body 20 is exposed to high heat of high temperature exhaust gas due to high load operation, or reaction of a catalyst. Is heated by the heat generated by the above, and further, it is overheated by the afterfire generated by the explosion of the unburned gas adhering thereto, and a larger thermal strain is generated.

Further, the catalyst metal carrier 1 is repeatedly subjected to violent vibration caused by violent vehicle body vibration, and the cylindrical case 10 and each fin 21 of the fin forming body 20 are in a severe vibration environment.

The catalyst metal carrier 1 is used as the tubular case 10, the fin forming body 20 and the retaining means of the present invention in order to ensure high durability even when used in the severe thermal environment and vibration environment as described above. The retaining member 40 is assembled as follows.

(Cylindrical case 10)
As shown in FIGS. 1, 2, and 3, the tubular case 10 is formed by bending a strip-shaped material (for example, SUS430 material, plate thickness 1.5 mm) of stainless steel plate into a cylindrical shape, with both ends thereof abutting each other. It is formed by welding by TIG welding or the like (weld portion W1).

(Fin forming body 20)
As shown in FIGS. 1, 2, and 4, the fin forming body 20 has a large number of plate-shaped fins 21 made of, for example, a stainless steel plate, and each fin 21 extends in the plate longitudinal direction on the inner peripheral surface of the cylindrical case 10. And a plurality of small exhaust passages 12 extending in the exhaust passage 11 by adjacent fins 21 extending in the exhaust passage 11 along the cylinder axis direction of the cylindrical case 10 in the plate width direction. Partition.

The fin forming body 20 of the present embodiment is composed of an integrated body in which a large number of plate-shaped fins 21 are machined so as to be integrated. In the present embodiment, the fin forming body 20 is formed by cutting out a stainless steel plate material or block body by laser processing.

Here, in the fin forming body 20 of the present embodiment, as shown in FIG. 4, a large number (12 in the present embodiment) of plate-shaped fins 21 are circumferentially spaced from the central portion 22 at a constant interval (the present embodiment). Has an outer ring portion 23 extending in the radial direction at intervals of 30 degrees) and connected to the tip end portion of each fin 21 and surrounding the fin 21. The fin 21, the center portion 22, and the outer ring portion 23 are integrated.

In the fin forming body 20 of the present embodiment, each fin 21 extends from the central portion 22 toward the outer ring portion 23 in a curved line (a quadratic curve or a cubic curve) such as a spiral line. However, each fin 21 may extend linearly from the central portion 22 toward the outer ring portion 23 along the radial direction. In this embodiment, the outer ring portion 23 has an endless circumferential shape that is continuous in the circumferential direction.

However, the fin forming body 20 does not necessarily need to include the outer ring portion 23 connected to the tip end portion of each fin 21.

In the fin forming body 20, a bent portion (for example, a U-shaped bent portion) 21R for absorbing thermal strain may be provided at an intermediate portion of each fin 21 in the plate longitudinal direction (FIG. 4D).

Further, a plurality of catalyst metal carriers 1 of the present embodiment are arranged inside the tubular case 10 in order from one end side along the exhaust passage 11 of the tubular case 10 to the other end side (in the present embodiment, 4 Fin forming bodies 20 are arranged. At this time, the fin forming bodies 20 aligned with each other are laminated by inverting the front and back sides thereof alternately as shown in the fin forming body 20 of FIG. 4A and the fin forming body 20 of FIG. 4B. As shown in FIG. 4C, the fins 21 that are adjacent to each other are arranged such that the fins 21 adjacent to each other have the curved directions (spiral directions) opposite to each other.

Here, when a plurality of fin forming bodies 20 are used and the fin forming bodies 20 arranged side by side from the one end side along the exhaust passage 11 of the tubular case 10 toward the other end side are alternately inverted and arranged, The non-overlapping portions of the end faces of the fins 21 of the aligned fin formations 20 are exposed to the exhaust passage 11 and the surface area of contact between the catalyst and the exhaust gas is increased, so that the exhaust gas purification performance is improved. Further, by providing a portion where the fins 21 do not overlap each other, a space where exhaust gas can flow into the exhaust gas downstream side of the fins 21 in the fin forming body 20 arranged on the upstream side is formed. Each of these spaces serves as an exhaust path that divides the exhaust flow into fine parts, and the exhaust flows that pass through different paths in the exhaust passage 11 interfere with each other to create resistance and the exhaust gas passes through the metal carrier 1. The time to do becomes longer. That is, the exhaust gas purification performance is further improved by increasing the contact time between the catalyst and the exhaust gas.

The plurality of fin-forming bodies 20 arranged side by side are not limited to being mutually inverted, but may be arranged so as to be offset from each other in the circumferential direction, be inverted with respect to each other and be displaced with respect to the circumferential direction, or are not inverted to each other, and You may arrange|position without shifting in the circumferential direction.

When a plurality of fin forming bodies 20 are used and arranged side by side from the one end side along the exhaust passage 11 of the tubular case 10 toward the other end side, the fin forming bodies 20 are arranged so as to be offset from each other by θ degrees in the circumferential direction, the fin forming bodies 20 are arranged side by side. The non-overlapping portions of the end faces of the fins 21 in the fin forming body 20 are exposed to the exhaust passage 11 and the surface area of contact between the catalyst and the exhaust gas is increased, so that the exhaust gas purification performance is improved. Further, by providing a portion where the fins 21 do not overlap each other, a space where exhaust gas can flow into the exhaust gas downstream side of the fins 21 in the fin forming body 20 arranged on the upstream side is formed. Each of the spaces serves as an exhaust path that divides the exhaust flow into fine parts, and the exhaust paths 11 and 12 interfere with each other to interfere with each other to cause resistance to the exhaust gas. The time to pass through becomes longer. That is, the exhaust gas purification performance is further improved by increasing the contact time between the catalyst and the exhaust gas.

By using a plurality of fin forming bodies 20, the fin forming bodies 20 arranged side by side from the one end side along the exhaust passage 11 of the tubular case 10 toward the other end side are alternately inverted, and the fin forming bodies 20 arranged side by side are reversed. When the fin-formed bodies 20 are arranged so as to be offset from each other by θ degrees in the circumferential direction, the non-overlapping portions of the end faces of the fins 21 of the fin-formed bodies 20 aligned with each other are exposed to the exhaust passage 11, and the surface area of contact between the catalyst and the exhaust gas increases. Exhaust gas purification performance is improved. Further, by providing a portion where the fins 21 do not overlap each other, a space where exhaust gas can flow into the exhaust gas downstream side of the fins 21 in the fin forming body 20 arranged on the upstream side is formed. Each of the spaces serves as an exhaust path that divides the exhaust flow into fine parts, and the exhaust paths 11 and 12 interfere with each other to interfere with each other to cause resistance to the exhaust gas. The time to pass through becomes longer. That is, the exhaust gas purification performance is further improved by increasing the contact time between the catalyst and the exhaust gas.

A plurality of fin forming bodies 20 are used, and the fin forming bodies 20 aligned from one end side to the other end side along the exhaust passage 11 of the tubular case 10 are not inverted and are not displaced in the circumferential direction (in the same direction). , And the fins 21 are arranged so as to overlap each other), the cross-sectional area of the small exhaust passage 12 defined by the fins 21 and the fins 21 aligned with each other in the metal carrier 1 is equal to the fin forming body. 20 is the same as the small exhaust flow passage cross-sectional area of the small exhaust flow passage 12 and the fin forming bodies 20 aligned side by side are alternately inverted, or the fins 21 of the fin forming bodies 20 aligned side by side are mutually θ in the circumferential direction. Compared with the case where they are arranged in a staggered manner or a case where they are combined, a small exhaust passage cross-sectional area can be secured widely, so exhaust resistance can be reduced and engine output can be improved. In addition, the state in which the fins 21 of the fin forming bodies 20 aligned with each other overlap at the same position from the exhaust upstream side to the exhaust downstream side of the metal carrier 1 is synonymous with increasing the plate width direction length of the fins 21. Since the effect of rectifying the exhaust gas is obtained inside the metal carrier 1, the reduction of the exhaust resistance becomes more remarkable.

(Prevention member 40)
The retaining member 40 prevents the fin forming body 20 from falling off the tubular case 10. The retaining member 40 is attached to the end face of the fin forming body 20 in the plate width direction of the fin forming body 20 without being joined to the fin forming body 20 by welding or the like. The fin forming body 20 is fixed and supported on the inner peripheral surfaces of both the exhaust upstream side and the exhaust downstream side, and prevents the fin forming body 20 from falling off in the cylinder axis direction.

At the exhaust upstream side of the tubular case 10 in which the fin forming body 20 is arranged, as shown in FIG. 2B, the inner diameter of the tubular case 10 is connected to the connection end of the exhaust pipe 60 to which the tubular case 10 is connected. When the small diameter portion 61 to be inserted into the portion is provided, the small diameter portion 61 of the exhaust pipe 60 serves as a retaining member on the exhaust upstream side, and the retaining member 40 in the present embodiment is used on the exhaust upstream side of the tubular case 10. It is not always necessary to provide it at the end of the. That is, the small diameter portion 61 of the exhaust pipe 60 is inserted into the inner diameter portion of the tubular case 10, and the end surface of the small diameter portion 61 is arranged so as to abut against the end surface of the outer ring portion 23 of the fin forming body 20. 20 is prevented from falling off the tubular case 10. At this time, a center cap 70, which will be described later, is fixed to an end surface around the center hole 24 of the central portion 22 of the fin forming body 20 facing the exhaust gas upstream side.

The retaining member 40 of the present embodiment is made of, for example, stainless steel, and as shown in FIG. 5, for example, three rod-shaped portions 42 extending from the central portion 41 in the circumferential direction at intervals of, for example, 120 degrees in the radial direction. In addition, each of the rod-shaped portions 42 has a mounting portion 43 that extends in the circumferential direction at both ends of the rod-shaped portion 42 and has a T-shape with the rod-shaped portions 42. The retaining member 40 is inserted into the inner peripheral surface of the tubular case 10 so as to be fitted from both the exhaust downstream side and the exhaust upstream side of the tubular case 10, and each mounting portion 43 is attached to the tubular case 10. The peripheral portion of the mounting portion 43 (three locations facing the outside of the cylindrical case 10 in this embodiment) is attached to the inner peripheral surface and is welded to the inner peripheral surface of the cylindrical case 10 by TIG welding or the like. (Welding part W2). At this time, although the rod-shaped portion 42 of the retaining member 40 is arranged on the front surface of each fin 21 in the fin forming body 20, it is attached to the fins 21 without being joined to the fins 21.

(Non-rotating shaft 50)
The rotation preventing shaft 50 is inserted into the central portion 22 of the fin forming body 20, and is engaged with the fin forming body 20 in a rotation preventing state in the circumferential direction of the fin forming body 20.

The anti-rotation shaft 50 of the present embodiment is provided at a plurality of positions (three positions in the present embodiment) projecting at regular intervals in the circumferential direction of the outer peripheral surface of a round bar made of stainless steel, and extends in the axial direction. It has an existing key-shaped convex portion 51. On the other hand, the central portion 22 of the fin forming body 20 has a detent center hole 24 having a detent groove 24A corresponding to the protrusion 51 of the detent shaft 50. The detent shaft 50 and the detent center hole 24 are provided with the protrusion 51 of the detent shaft 50 in the detent center hole 24 of the fin forming body 20 when they are inserted into each other so that they are fitted to each other. It is engaged in the stop groove 24A in the axial direction and is engaged in the circumferential direction thereof. The detent shaft 50 engaged with the detent center hole 24 of the fin forming body 20 is outward from the end face that faces the retaining member 40 in the central portion 22 of the fin forming body 20 (exhaust of the tubular case 10). A certain length (in the present embodiment, the thickness of the retaining member 40) is projected to the upstream side or the exhaust downstream side).

The detent shaft 50 may be integrally formed with the central portion 22 of the fin body 20.

The central portion 41 of the retaining member 40 includes a rotation preventing hole 44 having a recess 44A corresponding to the protrusion 51 of the rotation preventing shaft 50 protruding from the end face of the center portion 22 of the fin forming body 20. Then, the whirl-stop shaft 50 projecting from the end surface of the center portion 22 of the fin forming body 20 is inserted into the whirl-stop hole 44 provided in the retaining member 40 that is fixed to and supported by the end portion of the tubular case 10. When the rotation preventing shaft 50 is engaged, the protrusion 51 of the rotation preventing shaft 50 is axially engaged with the recess 44A of the rotation preventing hole 44 of the retaining member 40, and the rotation preventing shaft 50 engages with the rotation preventing hole 44 in the rotation preventing state. , TIG welding or the like (welding portion W3).

Here, on the side of the tubular case 10 facing the exhaust gas upstream side, the central cap is provided on the end face of the central portion 41 including the whirl-stop hole 44 of the retaining member 40 with which the whirl-stop shaft 50 is engaged and facing the exhaust gas upstream side. 70 is fixed. As shown in FIG. 7, the center cap 70 forms a conical umbrella-shaped body 71, and the conical base portion of the conical umbrella-shaped body 71 is attached to the peripheral edge portion of the central portion 41 of the retaining member 40 via a welding portion, a caulking portion, and the like. The conical umbrella-shaped body 71 is directed toward the exhaust upstream side so that the exhaust gas smoothly flows from the exhaust upstream side into the exhaust passage 11 (small exhaust passage 12) of the tubular case 10. ..

Here, the procedure for assembling the catalyst metal carrier 1 is as follows, for example.
(1) A plurality of fin forming bodies 20 are arranged side by side, and the detent shaft 50 is inserted into the detent center hole 24 provided in the central portion 22 of the fin forming bodies 20 arranged side by side. As a result, each fin forming body 20 is a laminated body in which the fins 21 are laminated so as to form a constant phase around their central portions 22.

(2) The laminated body of the fin forming bodies 20 of the above (1) is inserted so as to fit to the inner peripheral surface of the cylindrical case 10. At this time, the detent shaft 50 described in (1) above is installed in the exhaust passage 11 of the tubular case 10 from the end face of the center portion 22 of each fin forming body 20 located on the exhaust upstream side and the exhaust downstream side of the exhaust upstream side. Side and the exhaust downstream side.

(3) The retaining members 40 are inserted from both outsides of the tubular case 10 on the exhaust upstream side and the exhaust downstream side so as to fit into the inner peripheral surfaces thereof. At this time, the detent hole 44 of the retaining member 40 engages with the detent shaft 50 described in (2) above.

(4) The attachment portion 43 of the retaining member 40 inserted into the inner peripheral surface of the tubular case 10 by the above (3) is welded and fixed to the inner peripheral surface of the tubular case 10 by TIG welding or the like. Further, the rotation preventing hole 44 of the retaining member 40 and the outer peripheral surface of the retaining shaft 50 are welded and fixed by TIG welding or the like, and the center cap 70 faces the exhaust gas upstream side of the center portion of the retaining member 40. Fixed to.

The catalyst metal carrier 1 assembled as described above has a catalyst (oxidation catalyst) on the inner peripheral surface of the cylindrical case 10, the fin forming body 20, the retaining member 40, the rotation preventing shaft 50, and the surface of the center cap 70. , Reduction catalyst, or three-way catalyst, etc.) is applied and baked to be carried.

Therefore, according to the catalyst metal carrier 1 of the present embodiment, the following operational effects are exhibited.
(a) A retaining member 40 for preventing the fin forming body 20 from falling off the tubular case 10 is fixed and supported at the exhaust upstream side and exhaust downstream side ends of the tubular case 10 to form the fin forming body. The body 20 is held in the tubular axis direction of the tubular case 10. Further, the above-mentioned retaining member in which the rotation preventing shaft 50 engaged in the rotation preventing central hole 24 of the central portion 22 of the fin forming body 20 in the rotation preventing state is fixed and supported by the end portion of the tubular case 10. The member 40 is engaged with the rotation preventing hole 44 provided in the member 40 in a rotation preventing state, and is welded and fixed by TIG welding or the like. Therefore, the fin forming body 20 is prevented from rotating inside the tubular case 10 and is held in the tubular axis direction of the tubular case 10 to prevent the fin forming body 20 from falling out of the tubular case 10.

(b) The fin-forming body 20 is exposed to the above-mentioned high temperature exhaust gas even under a harsh use environment of an automobile engine, even under a long-time continuous use environment where the exhaust gas temperature is high at about 1000° C. to 1200° C. due to high load operation. It is not fixed to the cylindrical case 10 by using a brazing part that is exposed and melts. That is, the fin forming body 20 is stably held in the cylindrical case 10 by the above-described rotation preventing structure and retaining structure, which does not cause destruction even when exposed to high temperature exhaust gas, and the fin forming body 20 is formed into a cylindrical shape. It can be stably held in the case 10.

(c) The fin forming body 20 is stably held in the tubular case 10 by the above-described rotation preventing structure and retaining structure even when the vibration of the vehicle body and the engine of the automobile becomes severe, and the fin forming body 20 is kept in a tubular shape. It can be stably held in the case 10.

(d) The retaining member 40 is not joined to the fins 21 of the fin forming body 20, and holds the fin forming body 20 in the cylinder axis direction of the cylindrical case 10 to prevent the fin forming body 20 from coming off. The formation body 20 is reliably prevented from falling out. Here, the retainer member 40 is deformed in the plate longitudinal direction of each fin 21 by the relationship with the retainer member 40 as compared with a member that is fixed to each fin 21 of the fin forming body 20 by welding or the like. You will not be bound. As a result, the fin forming body 20 does not prevent thermal strain in the plate longitudinal direction of each fin 21 due to exposure to high-temperature exhaust gas due to the presence of the retaining member 40, and a large amount of heat due to this thermal strain. The stress is not generated between the retaining member 40 and the retaining member 40, and the retaining member 40 stably holds the stress.

(e) The fin forming body 20 has an engagement structure of a detent shaft 50 that engages with a detent center hole 24 of the center portion 22 in a detent state and an anti-rotation hole 44 provided in the retaining member 40. Then, it is prevented from rotating inside the tubular case 10. Accordingly, it is necessary to provide a fixing structure such as a welded portion, an engaging portion, a crimped portion, etc. for preventing rotation from the inner peripheral surface of the tubular case 10 on the outer peripheral side of the fin forming body 20. There will be no. Therefore, even if each fin 21 of the fin forming body 20 exposed to high temperature exhaust gas inside the exhaust passage 11 in the tubular case 10 thermally expands toward the outer end along the plate longitudinal direction, Due to the above-mentioned thermal expansion that extends to the outer peripheral portion of the fin forming body 20 that is the outer end, there is no risk of causing destruction or deformation of those fixing structures. Even if the outer peripheral portion of the fin forming body 20 that does not have such a fixing structure may simply increase the pressure contact state between the outer peripheral portion and the inner peripheral surface of the cylindrical case 10 due to the above-mentioned thermal expansion, There is no occurrence of a large thermal stress between the inner peripheral surface of the cylindrical case 10 and the inner peripheral surface of the cylindrical case 10 due to the thermal strain thereof. That is, the fin forming body 20 is stably held by the tubular case 10.

That is, the detent shaft 50 that engages in a detent state with the detent center hole 24 of the central portion 22 of the fin forming body 20 is provided, and this detent shaft 50 is provided in the retaining member 40. Since it is fixed to 44 in a non-rotating state, none of the members for the anti-rotation are heated by contacting only high-temperature exhaust gas inside the exhaust passage 11 without being cooled by the outside air. Thermal expansion occurs in a state where they are almost equal to each other, and the thermal strain generated in those members is small. Further, even if the thermal expansion toward the outer end along the longitudinal direction of each fin 21 in the fin forming body 20 is restrained by the presence of the tubular case 10, the thermal expansion is inward along the longitudinal direction of each fin 21. The one that only goes toward (the central portion 22 of the fin forming body 20) and compresses the detent shaft 50 engaged with the detent center hole 24 of the central portion 22 of the fin forming body 20 toward the center thereof. As a result, the detent shaft 50 is restrained more strongly. Therefore, the fin forming body 20 can be stably held inside the cylindrical case 10.

(f) The fin forming body 20 may be provided with a bent portion 21R for absorbing thermal strain at an intermediate portion of each fin 21 in the plate longitudinal direction.

In this case, the thermal strain of each fin 21 in the fin forming body 20 exposed to the high-temperature exhaust gas is absorbed by the thermal deformation of the bent portion 21R provided in the intermediate portion of the fin 21, and the tubular case 10 is accommodated. The fin-shaped body 20 can be stably held in the tubular case 10 because it does not cause a large thermal stress in the tubular case 10 and the tubular case is not destroyed.

Further, when the fins 21 of the fin forming body 20 are broken due to vibrations caused by violent vibrations of the vehicle body and the engine, the plate thickness of the fins 21 is increased to 0.8 to 3 mm, and the strength of the fin forming body 20 is reduced. Since it can be avoided by improving it, the fin forming body 20 can be stably held in the tubular case 10.

The structure in which the retaining member 40 does not restrain the deformation of each fin 21 of the fin forming body 20 in the plate longitudinal direction as described in (d) above has a structure in which the fins formed by the bent portions 21R provided in each fin 21 in (f) above are provided. The effect of not disturbing the thermal strain absorption effect of 21 is exerted.

(g) Inside the tubular case 10, a plurality of fin forming bodies 20 are arranged in order from one end side along the exhaust passage 11 of the tubular case 10 toward the other end side. The inner peripheral area over the entire length of the cylindrical case 10 supporting the catalyst and the total surface area of all the fin forming bodies 20 can be increased, and the purification performance of the catalyst metal carrier 1 can be improved.

(h) Since the fin forming body 20 is formed of an integrated body in which a large number of plate-shaped fins 21 are machined so as to be integrated, each fin 21 is, for example, a thick plate thickness 0.8 to The plate-like member having a thickness of 3 mm, more preferably 1 to 2 mm is used, and the heat resistance and vibration resistance of the fin forming body 20 can be secured, and the durability of the catalyst metal carrier can be easily secured.

In the catalyst metal carrier 1, a center cap 70 provided at an end portion of the detent shaft 50 fixed to a detent hole 44 provided in the exhaust prevention member 40 on the exhaust downstream side facing the exhaust upstream side, It can also function as a retaining means on the upstream side of the exhaust gas. At this time, the center cap 70 is integrally formed at the end of the rotation stopper shaft 50 facing the exhaust gas upstream side, or is provided by welding or the like, and is larger than the center hole 24 of the center portion 22 of the fin forming body 20. An umbrella-shaped body 71 having a diameter is provided. The detent shafts 50 with the central cap 70 are inserted into the central hole 24 of the central portion 22 of the fin forming body 20 arranged side by side from the exhaust upstream side, and the central cap 70 is attached to the fin forming body 20 on the exhaust upstream side. At this time, the end portion of the detent shaft 50 protruding outward from the fin forming body 20 on the exhaust downstream side engages with the detent hole 44 of the retaining member 40, and the retaining hole 44 is attached to the retaining member 40. The outer peripheral surface of the rotation preventing shaft 50 is welded and fixed by TIG welding or the like. As a result, the center cap 70 located on the upstream side of the exhaust gas is supported on the inner peripheral surface of the tubular case 10 via the whirl-stop shaft 50 and, by extension, the mounting portion 43 of the retaining member 40 located on the downstream side of the exhaust gas. It serves as a retaining means on the upstream side.

However, in the catalyst metal carrier 1, the exhaust upstream side (or exhaust downstream side) of the detent shaft 50 fixed to the detent hole 44 provided in the retaining member 40 on the exhaust downstream side (or exhaust upstream side). And the center hole 24 of the central portion 22 of the fin forming body 20 located on the most upstream side (or exhaust downstream side) of the exhaust gas are fixed by TIG welding or the like, and the detent shaft 50 and the fin forming body 20 are fixed. It is also possible to make the fixed portion of the central hole 24 of the above-mentioned fixed portion function as a retaining means on the exhaust upstream side (or the exhaust downstream side). As a result, the fixing portion of the rotation stop shaft 50 with the center hole 24 of the fin forming body 20 located on the most upstream side (or exhaust downstream side) of the exhaust gas is fixed to the rotation stop shaft 50, and thus to the exhaust downstream side (or exhaust upstream side). ) Is supported by the inner peripheral surface of the cylindrical case 10 via the attachment portion 43 of the retaining member 40 located at (), and serves as retaining means on the exhaust upstream side (or exhaust downstream side).

The catalytic metal carrier 2 shown in FIG. 8 is different from the catalytic metal carrier 1 shown in FIG. 1 in that the fin forming body 20 shown in FIG. 9 is used. This is because it has more than one projecting piece 25. The protrusions 25 of each fin 21 are provided over the entire area of each fin 21 in the plate width direction, and increase the total surface area of the fin forming body 20 that supports the catalyst, and improve the purification performance of the catalyst metal carrier 2. It becomes a thing.

In the catalyst metal carrier of the present invention, the fin forming body may be composed of a plate assembly in which a plurality of metal plates are combined, and each plate constituting the plate assembly is press-molded. It can consist of a body. According to this, each fin is formed into a plate shape with a plate thickness of 0.8 to 3 mm, and more preferably 1 to 2 mm, and the heat resistance strength, vibration resistance strength, etc. of the fin-formed body are secured, and the durability of the catalyst metal carrier is facilitated. Can be secured.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like within the scope not departing from the gist of the present invention. Included in the present invention. For example, in the fin forming body, the bent portion provided at the intermediate portion in the plate longitudinal direction of each fin is not limited to one intermediate portion in the plate longitudinal direction of the fin, but may be provided at each of a plurality of intermediate portions. ..

Further, in the fin forming body, the bent portion provided in each fin is not limited to one in which the bent portion is formed as a different curvature portion at a local position in the plate longitudinal direction compared to other positions, and It may be formed by being curved in a C-shape or an S-shape over substantially the entire length in the longitudinal direction.

In addition, the whirl-stop shaft provided at the center of the fin forming body is axially attached to at least one of the fin forming body and the retaining member while being axially coupled to both the fin forming body and the retaining member. Anything that can be combined is possible.

The structure in which the whirl-stop shaft and the fin-formed body are circumferentially coupled is a structure in which the whirl-stop shaft is integrally molded in the central portion of the fin-formed body, and the whirl-stop central hole provided in the central portion of the fin-formed body It is also possible to adopt a structure in which the caulking is stopped, a structure in which the anti-rotation shaft is engaged with a different-shaped anti-rotation central hole provided in the central portion of the fin forming body, and the like.

The structure in which the detent shaft and the retaining member are integrally coupled in the circumferential direction includes a structure in which the detent shaft is welded or caulked in a detent hole provided in the center of the retaining member, It is possible to adopt a structure or the like that engages with the non-rotating hole having a different shape provided at the center.

The coupling structure in the axial direction of the whirl-stop shaft and the fin forming body is a structure in which the whirl-stop shaft is integrally formed in the center of the fin forming body, and the whirl-stop center hole provided in the center of the fin forming body. It is possible to adopt a structure such as crimping.

The structure in which the whirl-stop shaft and the retaining member are integrally coupled in the axial direction includes a structure in which the whirl-stop shaft is welded or caulked to a retainer hole provided at the center of the retainer member, It is possible to employ a structure or the like that is engaged in a non-rotating hole having an opening of one end and a closed end of the other end (or a closed end of the other end) provided in the central portion in a retaining state.

In addition, constituent materials such as the cylindrical case, the fin forming body, and the retaining member that constitute the catalyst metal carrier are not particularly limited as long as they have excellent heat resistance.

According to the present invention, it is possible to provide a catalyst metal carrier capable of ensuring high durability under a severe use environment.

1, 2 Catalyst Metal Carrier 10 Cylindrical Case 11 Exhaust Passage 12 Small Exhaust Passage 20 Fin Forming Body 21 Fin 21R Bent Part 22 Central Part 24 Rotation Stop Central Hole 40 Detachment Member (Detachment Means)
44 Non-rotating hole 50 Non-rotating shaft

Claims (4)

A catalyst metal carrier in which a metal fin forming body is arranged inside an exhaust passage formed by a cylindrical case,
The fin forming body has a large number of plate-shaped fins, and each fin extends in the exhaust passage so as to intersect the inner peripheral surface of the cylindrical case in the plate longitudinal direction, and the fins adjacent to each other exhaust the exhaust gas. Dividing a number of small exhaust passages into the passage,
In a state where the retaining means for preventing the fin forming body from falling out of the tubular case holds the fin forming body in the tubular axis direction of the tubular case without being joined to the fins of the fin forming body, Supported by the tubular case,
The fin forming body has a detent shaft coupled to the fin forming body in a detent state in the circumferential direction of the fin forming body at a central portion of the fin forming body, and the detent shaft is supported by the tubular case to prevent the disengagement. A catalyst metal carrier fixed to the means in a non-rotating state. The catalyst metal carrier according to claim 1, wherein a plurality of fin forming bodies arranged in order from one end side to the other end side along the exhaust passage of the tubular case are arranged inside the tubular case. The catalyst metal carrier according to claim 1 or 2, wherein the fin-formed body is an integrally formed body in which a large number of plate-shaped fins are machined so as to be integrated. The catalyst metal carrier according to claim 1 or 2, wherein the fin forming body is a plate assembly formed by combining a plurality of metal plates.

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