JP5754189B2 - Catalytic converter device - Google Patents

Description

  The present invention relates to a catalytic converter device provided in an exhaust pipe of an internal combustion engine.

  In a catalytic converter device provided in an exhaust pipe for purifying exhaust gas generated in an internal combustion engine, for example, as described in Patent Document 1, a metal catalyst carrier supporting a catalyst is energized to raise the temperature, Some of them have a catalytic effect.

  By the way, in the structure described in Patent Document 1, a metal catalyst carrier is inserted into a shell (case), and a mat member having a buffer function is provided between the conductive member of the metal catalyst carrier and the shell. It is inserted and held.

  In the catalytic converter device having such a structure, when the carbon contained in the exhaust adheres to the upstream side of the metal catalyst carrier, the mat member, etc., the cylinder (metal shell) containing the metal catalyst carrier and the catalyst carrier The electrical resistance between the first and second electrodes is reduced by the carbon, and the current supply efficiency to the catalyst carrier is reduced.

JP-A-5-253491

  In view of the above facts, an object of the present invention is to obtain a catalytic converter device capable of suppressing a decrease in efficiency of energization to a catalyst carrier due to carbon contained in exhaust gas.

In the first aspect of the present invention, a catalyst carrier for purifying exhaust gas exhausted from the internal combustion engine is carried, the catalyst carrier is heated by energization, and the catalyst carrier is accommodated in a cylindrical shape. And a cylindrical body attached to the exhaust pipe, an inner elastic member disposed on the outer peripheral surface side of the catalyst carrier, an outer elastic member disposed on the inner peripheral surface side of the cylindrical body, and having insulation An intermediate member disposed between the inner elastic member and the outer elastic member, and holds the catalyst carrier in the cylinder by the elasticity of the inner elastic member and the outer elastic member, and electrically connects the catalyst carrier and the cylinder. a holding member for insulating, said provided in the intermediate member, the upstream side projecting portion inner peripheral surface with projecting upstream the inner elastic member and the non-contact of the upstream end portion is exposed to the inner elastic member , Provided in the upstream projecting portion, and the cylinder Having an upstream projecting portion projecting toward the center of the.

  In this catalytic converter device, when the catalyst carrier is energized and heated and heated, the purification effect of the supported catalyst can be exhibited earlier. In addition, the catalyst carrier is attached to the exhaust pipe via the holding member and the cylinder, and the intermediate member of the holding member has insulation, so the catalyst carrier and the cylinder are short-circuited by removing the holding member. Will never be done.

The exhaust gas may contain carbon generated by combustion of the internal combustion engine, and if this carbon adheres to the catalyst carrier or the cylinder, the electrical resistance between the cylinder and the catalyst carrier is reduced, and the catalyst carrier is energized. Efficiency may be reduced. In the present invention, the upstream protrusion of the intermediate member is not in contact with the inner elastic member, and the inner peripheral surface of the upstream protrusion is exposed. And the upstream protrusion part is provided in the upstream protrusion part. The upstream projecting portion projects toward the center of the cylinder to face the exhaust flow. For this reason, as compared with a member that is parallel to the flow direction of the exhaust gas without facing the exhaust gas, the exhaust gas directly hits and is easily heated by the exhaust heat. Thereby, even if carbon adheres to the upstream projecting portion, the carbon fuel can be promoted.

  Further, the upstream projecting portion projects toward the center of the cylindrical body, and serves as a throttle for the exhaust flow. For this reason, since the exhaust pressure increases at the location of the upstream projecting portion, the temperature rise is further promoted.

  And the intermediate member in which the upstream protrusion part was provided is arrange | positioned between the inner side elastic member and outer side elastic member which comprise a holding member. Thereby, a gap corresponding to the thickness of the outer elastic member is generated between the upstream protruding portion and the cylindrical body. Since the upstream protruding portion is not in contact with the cylindrical body, heat escape (radiation) from the upstream protruding portion to the cylindrical body via the upstream protruding portion can be suppressed, and the upstream protruding portion is effectively raised. Can be warm.

  In this way, by promoting the carbon fuel adhering to the upstream projecting portion, it is possible to suppress a decrease in the electrical resistance between the cylinder and the catalyst carrier due to the carbon adhering to the catalyst carrier and the cylinder. As a result, electricity can surely flow through the catalyst carrier, so that it is possible to suppress a decrease in the energization efficiency of the catalyst carrier.

  According to a second aspect of the present invention, in the first aspect of the invention, the upstream projecting portion is an upstream inclined portion that is inclined toward the downstream side in the flow direction toward the center of the cylindrical body. .

  As described above, the upstream projecting portion is inclined as the upstream inclined portion, so that the area on which the exhaust hits can be increased compared to the configuration in which the upstream protruding portion is not inclined (perpendicular to the flow direction of the exhaust). It can be secured.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the downstream projecting portion provided on the intermediate member and projecting further downstream than the downstream end portion of the inner elastic member ; And a downstream projecting portion provided on the downstream projecting portion and projecting toward the center of the cylindrical body.

  Therefore, since the downstream projecting portion also faces the exhaust flow obliquely, the exhaust directly hits and is easily heated by the exhaust heat. In addition, on the downstream side in the exhaust flow direction, the inner diameter of the downstream projecting portion decreases toward the center of the cylinder, and the exhaust pressure increases, so that the temperature rise is further promoted. Thereby, the fuel of carbon adhering to the downstream overhang | projection part can be promoted.

  According to a fourth aspect of the present invention, in the invention according to the third aspect, the combustion is applied to at least a part of the surface of the upstream projecting portion and the downstream projecting portion and promotes the combustion of adhering carbon. An accelerating member.

  In the portion where the fuel promoting member is applied, the combustion of carbon is further promoted, so that it is possible to more effectively suppress the decrease in electrical resistance between the cylinder and the catalyst carrier.

The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein an energizing member disposed in contact with the catalyst carrier and energizing the catalyst carrier; and the holding member An insertion hole portion that is formed through the thickness direction and passes through a part of the energization member; and a throttle portion that is provided in a portion located in the insertion hole portion of the intermediate member and approaches the catalyst carrier. Have .

  A part of the energization member is inserted into the insertion hole formed in the holding member, and the energization member is disposed in contact with the catalyst carrier. By energizing the catalyst carrier with this electricity supply member, the temperature of the catalyst carrier can be raised.

  The intermediate member is provided with a throttle portion at a portion located in the insertion hole. The throttle portion is close to the catalyst carrier, and the inner diameter of the intermediate member is partially reduced. Even if the water vapor contained in the exhaust gas is condensed to be condensed water (liquid) and enters the inner elastic member, it is suppressed by the throttle portion to reach the insertion hole. Since moisture stays in the inner elastic member in contact with the catalyst carrier, the heat of the catalyst carrier can act on the moisture in the inner elastic member to promote evaporation of the moisture.

  Since the present invention has the above-described configuration, it is possible to suppress a decrease in the energization efficiency to the catalyst carrier due to the carbon contained in the exhaust gas.

1 is a cross-sectional view showing a catalytic converter device according to a first embodiment of the present invention in a cross section including a center line in an attached state to an exhaust pipe. It is sectional drawing which expands and shows the catalytic converter apparatus of 1st Embodiment of this invention partially, (A) is the state in which carbon adhered, (B) is the state in which carbon was burned. It is sectional drawing which shows the catalytic converter apparatus of 2nd Embodiment of this invention in the cross section containing a centerline in the attachment state to an exhaust pipe. It is sectional drawing which shows the catalytic converter apparatus of 3rd Embodiment of this invention in the cross section containing a centerline in the attachment state to an exhaust pipe. It is sectional drawing which shows the catalytic converter apparatus of 4th Embodiment of this invention in the cross section containing a centerline in the attachment state to an exhaust pipe.

  FIG. 1 shows a catalytic converter device 12 according to a first embodiment of the present invention attached to an exhaust pipe 10.

  The catalytic converter device 12 has a catalyst carrier 14 formed of a material having conductivity and rigidity. As a material constituting the catalyst carrier 14, a conductive ceramic, a conductive resin, a metal, or the like can be applied. In the present embodiment, a conductive ceramic is particularly used.

  The catalyst carrier 14 is formed in a columnar shape or a cylindrical shape in which the surface area of the material is increased by configuring a thin plate having a honeycomb shape or a wavy shape into a spiral shape or a concentric shape, and a catalyst (platinum) is formed on the surface. , Palladium, rhodium, etc.) are attached.

  The catalyst has an action of purifying substances (HC and the like) in the exhaust gas (the flow direction is indicated by an arrow F1) flowing in the exhaust pipe 10. Note that the structure for increasing the surface area of the catalyst carrier 14 is not limited to the honeycomb shape or the wave shape described above.

  Two electrodes 16A and 16B are attached to the catalyst carrier 14 at positions symmetrical with respect to the catalyst carrier 14 (up and down in FIG. 1). Terminals 18A and 18B are connected to the electrodes 16A and 16B via conductor members 20A and 20B made of a conductive material such as metal, respectively. Each of the terminals 18A and 18B has a structure in which an insulating layer 24 covers the periphery of the central electrode rod 22. The outer end of the electrode rod 22 (the end opposite to the conductor members 20A and 20B) is a connection 22C to which a power supply cable to the catalyst carrier 14 is connected. The electrode rod 22, the conducting wire members 20A and 20B, and the electrodes 16A and 16B constitute an energizing member of the present invention.

  The insulating layer 24 is formed in a cylindrical shape from a material having electrical insulation. The insulating layer 24 covers the outer peripheral surface of the electrode rod 22 over the entire circumference, thereby preventing the flow of electricity from the electrode rod 22 to the cover portion 36 of the case cylinder 28.

  The conducting wire members 20A and 20B are formed in, for example, a zigzag shape or a spiral shape so as to have flexibility, and when the case cylinder 28 and the catalyst carrier 14 are relatively moved as described later, It is possible to absorb this relative movement. The catalyst carrier 14 can be heated by energizing the catalyst carrier 14 from the terminals 18A and 18B through the conductor members 20A and 20B and the electrodes 16A and 16B. By this heating, the temperature of the catalyst supported on the catalyst carrier 14 is raised, so that the purification action of the catalyst can be exhibited at an early stage even immediately after the engine is started.

  The catalyst carrier 14 is held in a state of being accommodated inside a case cylinder 28 (cylinder according to the present invention) by a holding mat 26 (holding member according to the present invention) arranged on the outer periphery. In other words, the catalyst carrier 14 is accommodated inside the substantially cylindrical case cylinder 28, and the catalyst carrier 14 is placed in the case by the holding mat 26 disposed between the case cylinder 28 and the catalyst carrier 14. The cylinder 28 is held concentrically (center line CL). Since the insulating holding mat 26 is disposed between the catalyst carrier 14 and the case cylinder 28, the flow of electricity from the catalyst carrier 14 to the case cylinder 28 is prevented.

  The case cylinder 28 is formed in a substantially cylindrical shape with a metal such as stainless steel, and has an upstream taper portion 28A having a diameter gradually increased toward the downstream on the upstream side in the flow direction, and an upstream taper at the intermediate portion in the flow direction. A large-diameter portion 28B that is continuous from the portion 28A and has a larger diameter than the exhaust pipe 10, and a downstream tapered portion 28C that is continuous from the large-diameter portion 28B and has a diameter gradually decreased toward the downstream side. doing.

  The downstream end of the front pipe 10A of the exhaust pipe 10 is at the upstream end of the upstream tapered section 28A, and the upstream end of the rear pipe 10B of the exhaust pipe 10 is at the downstream end of the downstream tapered section 28C. They are connected to each other, and the flow passage cross-sectional area of the exhaust gas is locally expanded at the portion of the case cylinder 28 (particularly, the large diameter portion 28B).

  The large-diameter portion 28B is provided with a substantially cylindrical cover portion 36 that can accommodate the terminals 18A and 18B. In the state where the terminals 18 </ b> A and 18 </ b> B are inserted into the cover portion 36, the opening portion of the cover portion 36 is closed by the lid plate 38.

  The holding mat 26 disposed on the outer periphery of the catalyst carrier 14 is formed in a substantially cylindrical shape having a three-layer structure of an inner fiber layer 30, an intermediate cylinder layer 32, and an outer fiber layer 34 in order from the inside. A large-diameter portion 28 </ b> B of the case cylinder 28 is located on the outer periphery of the holding mat 26. The inner fiber layer 30 corresponds to the inner elastic member of the present invention, the intermediate cylinder layer 32 corresponds to the intermediate member of the present invention, and the outer fiber layer 34 corresponds to the outer elastic member of the present invention.

  The inner peripheral surface of the inner fiber layer 30 is in contact with the outer peripheral surface of the catalyst carrier 14, and the outer peripheral surface of the outer fiber layer 34 is in contact with the inner peripheral surface of the case cylinder 28. The inner fiber layer 30 and the outer fiber layer 34 are formed in a fiber shape having insulating properties and predetermined elasticity using, for example, an alumina mat, a resin mat, ceramic wool, or the like. As a result, the holding mat 26 itself has a predetermined elasticity, and the holding mat 26 is arranged so that the catalyst carrier 14 is concentric (center line CL) inside the substantially cylindrical case cylinder 28. keeping.

  On the other hand, in the present embodiment, the intermediate cylinder layer 32 is configured so that at least the surface has insulating properties, and is formed in a cylindrical shape as a whole. For example, the material itself may be insulative (resin or the like), or the surface of a cylindrical metal tube may be coated with an insulating material. In any case, the inner fiber layer 30 and the outer fiber layer 34 having insulation and elasticity are arranged on the inner peripheral side and the outer peripheral side of the intermediate cylindrical layer 32 having shape stability by a solid material, and the catalyst carrier 14 is It is stably held inside the case cylinder 28. However, in the present embodiment, since the insulating property of the holding mat 26 is ensured by the intermediate cylinder layer 32, the inner fiber layer 30 and the outer fiber layer 34 are not necessarily required to be insulated.

  In particular, since the linear expansion coefficient is different between the metal case cylinder 28 and the conductive ceramic catalyst carrier 14, the heat of the exhaust gas passing through the exhaust pipe 10 and the expansion due to the current heating to the catalyst carrier 14 are expanded. The amount is different. This difference in expansion amount is absorbed by the elasticity of the holding mat 26. Further, even when vibration is input through the exhaust pipe 10, the holding mat 26 exhibits a buffering action and absorbs a positional deviation between the case cylinder 28 and the catalyst carrier 14.

  In addition, since the holding mat 26 having insulating properties as a whole is disposed between the catalyst carrier 14 and the case cylinder 28, the flow of electricity from the catalyst carrier 14 to the case cylinder 28 is prevented. . As a material constituting the inner fiber layer 30 and the outer fiber layer 34, an interlam mat, mullite, or the like is also applicable.

  The large diameter portion 28B, the outer fiber layer 34, the intermediate cylinder layer 32, and the inner fiber layer 30 of the case cylinder 28 are formed with through holes through which the terminals 18A and 18B are penetrated, and are in contact with the terminals 18A and 18B. It is supposed not to. The inside of the through hole is an insertion hole portion 42. Accordingly, part of the terminals 18A and 18B, the conductor members 20A and 20B, and the electrodes 16A and 16B are accommodated in the insertion hole portion 42.

  In this embodiment, the inner fiber layer 30 and the outer fiber layer 34 are formed in the same length as the catalyst carrier 14 in the axial direction (exhaust flow direction). The upstream end surface 30A and the downstream end surface 30B of the inner fiber layer 30 are in the same position as the upstream end surface 14A and the downstream end surface 14B of the catalyst carrier 14 in the axial direction (exhaust flow direction). Similarly, the upstream end surface 34A and the downstream end surface 34B of the outer fiber layer 34 are also in the same position in the axial direction as the upstream end surface 14A and the downstream end surface 14B of the catalyst carrier 14, respectively.

  On the other hand, the intermediate cylinder layer 32 is formed longer in the axial direction than the catalyst carrier 14, the inner fiber layer 30, and the outer fiber layer 34. The intermediate cylinder layer 32 is provided with an upstream protrusion 32U that protrudes upstream from the inner fiber layer 30. Further, the intermediate cylindrical layer 32 is provided with a downstream protruding portion 32 </ b> L that protrudes downstream from the inner fiber layer 30. The upstream protruding portion 32U and the downstream protruding portion 32L are not in contact with the case cylinder 28, and gap portions 44U and 44L are formed, respectively.

  In particular, in the present embodiment, the upstream protrusion 32U and the downstream protrusion 32L are circumferentially spaced apart from the inner peripheral surface of the large diameter portion 28B of the case cylinder 28 in the radial direction. It is formed all around. Therefore, the gap portions 44U and 44L are also formed on the entire circumference in the circumferential direction of the catalyst carrier 14.

  An upstream inclined member 46 is provided on the inner side of the upstream protruding portion 32 </ b> U of the intermediate cylinder layer 32. The upstream inclined member 46 as a whole is formed in a substantially truncated cone shape (strictly, a shape in which the upper bottom portion and the lower bottom portion are removed from the truncated cone and only the side surface portion is formed). The upstream inclined member 46 is arranged such that the direction from the large diameter portion 46L toward the small diameter portion 46S is the exhaust flow direction (the direction of the arrow F1), and the upstream protrusion 32U is located at the large diameter portion 46L. Is attached. Therefore, the upstream inclined member 46 as a whole is inclined with respect to the exhaust flow direction (the direction of the arrow F1). In particular, the inner peripheral surface 46N of the upstream inclined member 46 is diagonally opposed to the exhaust flowing in the direction of arrow F1, and the exhaust directly hits the inner peripheral surface 46N. Further, the substantial cross-sectional area of the exhaust passage is gradually reduced from the large diameter portion 46L of the upstream inclined member 46 toward the small diameter portion 46S. The upstream inclined member 46 is an example of an upstream projecting portion of the present invention.

  A downstream inclined member 48 is provided on the inner side of the downstream protruding portion 32 </ b> L of the intermediate cylinder layer 32. The downstream inclined member 48 as a whole is also substantially in the shape of a truncated cone similar to the upstream inclined member 46, and the direction from the large diameter portion 48L to the small diameter portion 48S is the direction in which the exhaust gas flows (arrow F1 direction). The large-diameter portion 46L is attached to the downstream protrusion 32L. The inner peripheral surface 48N of the downstream inclined member 48 is diagonally opposed to the exhaust flowing in the direction of the arrow F1, and the exhaust directly hits the inner peripheral surface 48N (does not hit the outer peripheral surface 48G directly). Further, the substantial cross-sectional area of the exhaust passage is gradually reduced from the large diameter portion 48L of the downstream inclined member 48 toward the small diameter portion 48S. The downstream side inclined member 48 is an example of the downstream side overhanging portion of the present invention.

  The intermediate cylindrical layer 32 is formed with an extending portion 50 that slightly extends into the insertion hole portion 42.

  Next, the operation of the catalytic converter device 12 of this embodiment will be described.

  As shown in FIG. 1, the catalytic converter device 12 is attached so that the case cylinder 28 is concentric with the exhaust pipe 10 in the middle of the exhaust pipe 10 (between the front pipe 10A and the rear pipe 10B). Exhaust gas passes through the inside of the catalyst carrier 14. At this time, the substance (HC or the like) in the exhaust gas is purified by the catalyst supported on the catalyst carrier 14.

  In the catalytic converter device 12 of the present embodiment, the catalyst carrier 14 is heated by energizing the catalyst carrier 14 by the terminals 18A and 18B, the conductor members 20A and 20B, and the electrodes 16A and 16B, thereby heating the catalyst carrier 14. The temperature can be raised, and the purification action can be exhibited earlier. For example, when the temperature of the exhaust gas is low, such as immediately after starting the engine, the catalyst purification performance in the initial stage of engine starting can be ensured by conducting energization heating to the catalyst carrier 14 in advance.

  The exhaust gas contains carbon, and if the catalyst carrier 14 and the case cylinder 28 are electrically short-circuited by the carbon, the energization efficiency of the catalyst carrier 14 may be reduced. As a result, there is a concern that the heating efficiency of the catalyst supported on the catalyst carrier 14 also decreases.

  Here, in the catalytic converter device 12 of the present embodiment, the upstream side inclined member 46 is arranged on the upstream side of the catalyst carrier 14. The inner peripheral surface 46N of the upstream inclined member 46 is diagonally opposed to the exhaust flowing in the direction of arrow F1, and the exhaust directly hits the inner peripheral surface 46N. That is, by adhering a part of the carbon in the exhaust to the inner peripheral surface 46N of the upstream inclined member 46, the amount of carbon reaching the catalyst carrier 14 can be reduced. In addition, since the exhaust does not directly hit the outer peripheral surface 46G of the upstream inclined member 46, the amount of attached carbon is smaller than that of the inner peripheral surface 46N.

  As described above, since the exhaust directly hits the inner peripheral surface 46N of the upstream inclined member 46, the upstream inclined member 46 has a structure in which the heat of the exhaust is easily transmitted. Moreover, the cross-sectional area of the exhaust passage is gradually reduced by the upstream inclined member 46 from the large diameter portion 46L to the small diameter portion 46S of the upstream inclined member 46, and in the vicinity of the upstream inclined member 46, the exhaust gas is exhausted. The pressure increases.

  As a result, in the upstream inclined member 46, the temperature easily rises due to heat acting from the exhaust, and the carbon fuel adhering to the upstream inclined member 46 can be promoted. For example, as shown in FIG. 2 (A), even if carbon adheres to the upstream inclined member 46 and its vicinity, the combustion of this carbon is promoted, as shown in FIG. 2 (B). In the vicinity of the upstream inclined member 46, no carbon is present, so that a short circuit between the catalyst carrier 14 and the case cylinder 28 due to carbon can be suppressed.

  As described above, the amount of carbon adhering to the outer peripheral surface 46G of the upstream inclined member 46 is small, but the heat of the inner peripheral surface 46N is also transmitted to the outer peripheral surface 46G through the inside of the upstream inclined member 46. For this reason, combustion of carbon adhering to the outer peripheral surface 46G can also be promoted.

  Further, in the catalytic converter device 12 of the present embodiment, the downstream inclined member 48 is disposed on the downstream side of the catalyst carrier 14. Even if the carbon in the exhaust gas that has passed through the catalyst carrier 14 adheres to the downstream side inclined member 48, similarly to the upstream side inclined member 46, the temperature increase of the downstream side inclined member 48 is promoted. Since the adhering carbon fuel is also promoted, a short circuit between the catalyst carrier 14 and the case cylinder 28 caused by the carbon in the vicinity of the downstream inclined member 48 can be suppressed.

  Further, in the catalytic converter device 12 of the present embodiment, the upstream protrusion 32U and the downstream protrusion 32L of the intermediate cylinder layer 32 are not in contact with the case cylinder 28, and the case cylinder 28 and the intermediate cylinder layer 32 are in contact with each other. Clearances 44U and 44L are formed between the two. Here, assuming a configuration in which the intermediate cylinder layer 32 is in contact with the case cylinder 28, in this configuration, the heat of the intermediate cylinder layer 32 easily escapes to the outside through the case cylinder 28. However, in this embodiment, since heat is not directly transferred from the intermediate cylinder layer 32 to the case cylinder 28, the temperature rise of the intermediate cylinder layer 32 can be more effectively promoted. This also promotes the carbon fuel in the vicinity of the upstream side inclined member 46 and the downstream side inclined member 48.

  FIG. 3 shows a catalytic converter device 52 according to a second embodiment of the present invention. The catalytic converter device 52 of the second embodiment has substantially the same configuration as the catalytic converter device 12 of the first embodiment, but the inner peripheral surface 46N of the upstream side inclined member 46 and the inner peripheral surface of the downstream side inclined member 48. The combustion promoting member 54 is applied to 48N. Except this, the catalytic converter device 52 of the second embodiment is the same as the catalytic converter device 12 of the first embodiment.

  Therefore, the catalytic converter device 52 of the second embodiment also has substantially the same operational effects as the catalytic converter device 12 of the first embodiment, but in particular, carbon adhering to the upstream side inclined member 46 and the downstream side inclined member 48. The fuel temperature is decreased by the combustion promoting member 54. Thereby, combustion of carbon can be further promoted.

  In the second embodiment, as a specific material of the combustion promoting member 54, for example, platinum may be a noble metal such as vanadium that has an effect of lowering the fuel temperature of carbon.

  FIG. 4 shows a catalytic converter device 62 according to a third embodiment of the present invention. Also in the third embodiment, the same components and members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the catalytic converter device 62 of the third embodiment, by deforming the upstream protruding portion 32U of the intermediate cylinder layer 32 (in other words, on the intermediate cylinder layer 32 itself), the upstream slope is formed upstream in the exhaust flow direction. A portion 66 is formed. The small-diameter portion 66S of the upstream inclined portion 66 has a smaller diameter than the cylindrical portion 32P (a portion having a constant diameter) of the intermediate cylindrical layer 32, and the small-diameter portion 66S and the cylindrical portion 32P are connected to each other. They are connected by the part 66C. An inner peripheral surface 66N of the upstream inclined portion 66 is diagonally opposed to the exhaust gas flowing in the direction of arrow F1.

  Further, in this catalytic converter device 62, the downstream inclined portion 68 is formed by deforming the downstream protruding portion 32 </ b> L of the intermediate cylindrical layer 32. The large-diameter portion 68L of the downstream inclined portion 68 is directed to the upstream side in the exhaust flow direction and the small-diameter portion 68S is directed to the downstream side, and the inner peripheral surface 68N is diagonally opposed to the exhaust flow.

  In the third embodiment, the intermediate cylinder layer 32 is extended further downstream than the downstream inclined portion 68, and an extension portion 68E is configured. Thereby, the intermediate cylinder layer 32 according to the third embodiment has a symmetrical shape in the exhaust flow direction (left-right direction in FIG. 4).

  Also in the catalytic converter device 62 of the third embodiment having such a configuration, the exhaust directly hits the upstream inclined portion 66. Further, in the small diameter portion 66S of the upstream inclined portion 66, the cross-sectional area of the exhaust passage is narrow. As a result, the temperature of the upstream inclined portion 66 can be effectively raised, and the combustion of carbon adhering to the inner peripheral surface 46N can be promoted.

  Further, although it is difficult for carbon to adhere to the outer peripheral surface 66G of the upstream inclined portion 66, the temperature of the carbon attached to the outer peripheral surface 66G is also raised by the heat transmitted from the inner peripheral surface 66N to the inside of the upstream inclined portion 66. Therefore, combustion of the carbon adhering to the outer peripheral surface 66G can be promoted.

  Further, similarly to the upstream inclined portion 66, the temperature increase is promoted in the downstream inclined portion 68 as well. Carbon fuel adhering to the inner peripheral surface 68N is promoted, heat is also transmitted to the outer peripheral surface 68G, and combustion of carbon adhering to the outer peripheral surface 68G is also promoted.

  Further, in the third embodiment, the intermediate cylindrical layer 32 is provided by providing the upstream inclined portion 66 and the connecting portion 66C on the upstream side of the intermediate cylindrical layer 32 and the downstream inclined portion 68 and the extending portion 68E on the downstream side. The area to which carbon can adhere is increased. For this reason, it is possible to reduce the thickness (height in the deposition direction) of the carbon adhering to the intermediate cylinder layer 32 (particularly, the upstream inclined portion 66 and the downstream inclined portion 68).

  FIG. 5 shows a catalytic converter device 72 according to a fourth embodiment of the present invention. The catalytic converter device 72 of the fourth embodiment has substantially the same configuration as the catalytic converter device 62 of the third embodiment, but differs in that a throttle portion 74 is provided in the intermediate cylinder layer 32. .

  That is, in the catalytic converter device 62 of the fourth embodiment, the throttle portion 74 that approaches the center of the catalytic converter device 12, that is, the catalyst carrier 14, is formed from the extending portion 50 in the intermediate cylindrical layer 32. Therefore, in the throttle part 74, the intermediate cylinder layer 32 is partially reduced in diameter. When viewed in the exhaust flow direction (arrow F1 direction), the throttle portion 74 is present as a wall at a position closer to the center of the insertion hole portion 42 than the inner fiber layer 30.

  The catalytic converter device 72 of the fourth embodiment configured as described above has substantially the same operational effects as the catalytic converter device 62 of the third embodiment, but further, water vapor in the exhaust is condensed and liquefied. In addition, the condensed water is prevented from entering the insertion hole 42.

  That is, the condensed water in which the moisture in the exhaust is condensed may permeate the inner fiber layer 30 and move downstream. However, since the movement of the condensed water is blocked by the throttle portion 74 and does not reach the insertion hole portion 42, the catalyst carrier 14 and the electrodes 16A and 16B and the case cylinder 28 in the insertion hole portion 42 due to the condensed water are caused. And short circuit can be suppressed.

  The condensed water stays in the inner fiber layer 30, but heat from the catalyst carrier 14 acts on the inner fiber layer 30. For this reason, the inflow to the insertion hole 42 can be further suppressed by evaporating the condensed water.

  Further, the combustion promoting member 54 according to the second embodiment may be applied to the catalytic converter device 62 of the third embodiment or the catalytic converter device 72 of the fourth embodiment.

  In each of the above-described embodiments, the catalytic converter device having a structure including the downstream protruding portion and the downstream inclined portion (or the downstream inclined member) has been described, but at least the upstream protruding portion and the upstream inclined portion (or the upstream inclined member). ), It is possible to obtain a configuration that exhibits the essential effects of the present invention.

  In the first embodiment and the second embodiment, the upstream inclined member 46 and the downstream inclined member 48 are separated from the intermediate cylinder layer 32 (the upstream protruding portion 32U and the downstream protruding portion 32L). The degree of freedom of the shapes of the inclined member 46 and the downstream inclined member 48 is high.

  In contrast, in the third embodiment and the fourth embodiment, the upstream inclined portion 66 and the downstream inclined portion 68 are integrated with the intermediate cylindrical layer 32 (the upstream protruding portion 32U and the downstream protruding portion 32L). Therefore, the number of parts is reduced.

  In each of the above-described embodiments, the intermediate cylinder layer 32 may be made of, for example, a material that has an insulating property (resin is ceramic or the like), but is based on a material that does not have an insulating property (for example, a metal). It may be used as a material, and the surface of this base material may be coated with an insulating member. In particular, when a metal is used as the base material of the intermediate cylinder layer 32, since the metal generally has a higher thermal conductivity than a resin, ceramic, or the like, the heat of the exhaust is efficiently transmitted to the insertion hole 42, The evaporation of moisture accumulated in the insertion hole 42 (around the electrodes 16A and 16B) can be promoted.

  In the above, the upstream side inclined member 46 and the upstream side inclined part 66 are mentioned as the upstream side extended part of the present invention, but the upstream side extended part is thus inclined with respect to the exhaust flow direction. There is no need, and for example, a member orthogonal to the flow direction of the exhaust gas may be used. The downstream projecting portion is not limited to the downstream inclined member 48 and the downstream inclined portion 68, and may be a member orthogonal to the exhaust flow direction. However, if it is made to incline with respect to the flow direction of the exhaust as in the above embodiment, the surface area can be increased while the opening cross-sectional areas of the small diameter portions 46S, 48S, 66S, 68S are secured.

  The intermediate member of the present invention need not surround the periphery of the catalyst carrier 14 when viewed in the direction of the arrow F1, but by forming the surrounding shape, the catalyst carrier 14 and the upstream projecting portion (upstream inclined portion) ) And the downstream projecting portion (downstream inclined portion) to the case cylinder 28 can be effectively suppressed.

10 Exhaust pipe 12 Catalytic converter device 14 Catalyst carrier 16A, 16B Electrode (energization member)
18A, 18B Terminal (electrical member)
20A, 20B Conductor member (electrically conductive member)
26 Holding mat (holding member)
28 Case cylinder (cylinder)
30 Inner fiber layer (inner elastic member)
30A upstream end face 32 intermediate cylinder layer (intermediate member)
32U upstream protrusion 32L downstream protrusion 34 outer fiber layer (outer elastic member)
42 Insertion hole 46 Upstream inclined member (upstream inclined portion, upstream protruding portion)
48 Downstream inclined member (downstream inclined part, downstream protruding part)
52 Catalytic Converter Device 54 Combustion Promoting Member 62 Catalytic Converter Device 66 Upstream Inclined Part (Upstream Side Overhanging Part)
68 Downstream inclined part (downstream projecting part)
72 catalytic converter device 74 throttle part

Claims (5)

A catalyst carrier that carries a catalyst for purifying exhaust gas discharged from the internal combustion engine and is heated by energization;
A cylindrical body that is formed in a cylindrical shape and contains the catalyst carrier therein and is attached to the exhaust pipe;
An inner elastic member disposed on the outer peripheral surface side of the catalyst carrier, an outer elastic member disposed on the inner peripheral surface side of the cylindrical body, and an insulating property between the inner elastic member and the outer elastic member. A holding member that holds the catalyst carrier in the cylinder by the elasticity of the inner elastic member and the outer elastic member and electrically insulates the catalyst carrier and the cylinder,
Said provided in the intermediate member, the upstream side projecting portion inner peripheral surface with projecting upstream the inner elastic member and the non-contact of the upstream end portion is exposed to the inner elastic member,
An upstream projecting portion provided on the upstream projecting portion and projecting toward the center of the cylindrical body;
A catalytic converter device.   2. The catalytic converter device according to claim 1, wherein the upstream projecting portion is an upstream inclined portion that is inclined toward the downstream side in the flow direction toward the center of the cylindrical body. A downstream projecting portion provided on the intermediate member and projecting downstream from the downstream end of the inner elastic member ;
A downstream projecting portion provided on the downstream projecting portion and projecting toward the center of the cylindrical body;
The catalytic converter device according to claim 1 or 2, comprising:   4. The catalytic converter device according to claim 3, further comprising: a combustion promoting member that is applied to at least a part of the surface of the upstream projecting portion and the downstream projecting portion and promotes combustion of attached carbon. A current-carrying member disposed in contact with the catalyst carrier for energizing the catalyst carrier;
An insertion hole portion that is formed through the holding member in the thickness direction and for inserting a part of the energization member;
A throttle portion provided in a portion located in the insertion hole of the intermediate member and approaching the catalyst carrier;
The catalytic converter device according to any one of claims 1 to 4, comprising:

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