JP5612949B2 - Honeycomb structure and filter device - Google Patents

Description

  The present invention relates to a honeycomb structure and a filter device.

  Due to the recent increase in awareness of environmental issues, vehicles have been required to reduce carbon dioxide emissions. With this demand, the demand for diesel engines is increasing. It is known that exhaust gas containing a large amount of soot (particulate matter, PM) is discharged from a diesel engine. It is required to remove this PM when exhaust gas is discharged into the atmosphere. PM discharged from the diesel engine is collected by a porous ceramic filter called a diesel particulate filter (DPF).

  In the DPF, when the collected soot (PM) is kept as it is, the PM hinders the passage of the exhaust gas and the pressure loss (hereinafter referred to as pressure loss) increases. In order to suppress an increase in pressure loss, it is required to remove the collected PM, and a method of burning and decomposing the collected PM is known (filter regeneration). When the PM burns, the collected PM does not exist (is removed), and the pressure loss returns to the state before the PM is collected (the increased pressure loss decreases).

  However, since the exhaust gas from the diesel engine has a low temperature, forced regeneration means for burning and removing PM must be assembled in the exhaust system.

  As the forced regeneration means, an oxidation catalyst disposed upstream of the DPF or supported on the DPF is used. In this forced regeneration means, the temperature of the exhaust gas flowing into the DPF is raised by further adding fuel to the cylinder (combustion chamber) or exhaust pipe of the engine and burning the fuel added by the oxidation catalyst. Then, PM trapped in the DPF is burned and removed by the heated exhaust gas.

  However, there is a problem that fuel is consumed in addition to driving the engine (traveling the vehicle), resulting in deterioration of fuel consumption.

  And the forced regeneration means for preventing the deterioration of a fuel consumption is disclosed by patent documents 1-2, for example. Patent Documents 1 and 2 describe that an electric heater is installed upstream of a DPF in a vehicle using electric power as a power source such as a diesel hybrid vehicle.

  However, in these forced regeneration means, since the electric heater is installed, there is a problem that the whole structure is complicated and the number of parts is increased.

JP-A-10-155202 JP 2005-282527 A

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a honeycomb structure and a filter device having a simple structure and excellent reproducibility.

  In order to solve the above-mentioned problems, the present inventors have made studies on the honeycomb structure and the filter device, and as a result, have reached the present invention.

That is, the honeycomb structure of the present invention is a honeycomb structure having a segment portion made of conductive porous ceramics, in which a plurality of cells extending in the axial direction are partitioned, and a connection portion connecting the plurality of segment portions. The connecting portion is made of a conductive material and is formed so as to connect at least a part of the opposing surfaces of the pair of segment portions to be connected, and between the outer peripheral surfaces of the pair of segment portions, There are non-connecting portion is not formed is formed, and the non-connecting portion, the filler for bonding the segment portion is characterized in that it is arranged is filled throughout.

The filter device of the present invention is characterized by using the honeycomb structure according to any one of the first to ninth aspects.

  The honeycomb structure of the present invention has a configuration in which conductive segment portions are connected by conductive connection portions. That is, the honeycomb structure itself has conductivity. In this configuration, electricity (current) flows when a voltage is applied to the honeycomb structure, and the honeycomb structure itself generates heat. That is, the honeycomb structure of the present invention is capable of self-heating, and when used as a filter (filter device) such as a DPF, it is possible to remove the collected PM using heat generated by self-heating. Demonstrate. That is, the honeycomb structure of the present invention is a honeycomb structure excellent in reproducibility.

  The filter device of the present invention uses the honeycomb structure that exhibits the above-described effects, and exhibits the above-described effects.

FIG. 3 is a view showing an upstream end face of a honeycomb structure of Example 1. 3 is a schematic cross-sectional view showing a configuration of a honeycomb structure of Example 1. FIG. 3 is a schematic cross-sectional view showing a configuration of a honeycomb structure of Example 1. FIG. FIG. 3 is a diagram illustrating an upstream end face of the DPF according to the first embodiment. 1 is a diagram showing a structure of a DPF of Example 1. FIG. It is the figure which showed the end surface of the upstream of the honeycomb structure of a comparative example. FIG. 3 is a diagram showing a relationship between energization power and temperature of the honeycomb structure of Example 1. FIG. 3 is a diagram showing a relationship between energization power and temperature of the honeycomb structure of Example 1. FIG. 3 is a diagram showing a relationship between energization power and temperature of the honeycomb structure of Example 1. It is a schematic sectional drawing which shows the structure of the honeycomb body of the honeycomb structure of a 1st modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 1st modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 2nd modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 2nd modification. It is the figure which showed the end surface of the honeycomb structure of a 3rd modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 3rd modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 3rd modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 4th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 4th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 5th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 5th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 6th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 6th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 7th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 7th modification. It is the figure which showed the end surface of the upstream of the honeycomb structure of a 8th modification. It is a schematic sectional drawing which shows the cross section of the honeycomb structure of an 8th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 9th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 10th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 10th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of an 11th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of an 11th modification. It is a schematic sectional drawing which shows the structure of the honeycomb structure of a 12th modification. FIG. 6 is a view showing an end face on the upstream side of the DPF of Example 2. FIG. 4 is a diagram showing a structure of a DPF in Example 2.

(Honeycomb structure)
The honeycomb structure of the present invention is a honeycomb structure having a segment portion made of conductive porous ceramics, in which a plurality of cells extending in the axial direction are partitioned, and a connection portion connecting the plurality of segment portions.

  In the honeycomb structure of the present invention, the connection portion is made of a conductive material, and is formed so as to connect at least a part of the opposed surfaces of the pair of segment portions to be connected. Between the surfaces, a non-connection portion in which no connection portion is formed is formed.

  In the honeycomb structure of the present invention, the connection portion is formed of a conductive material. Since the segment part made of conductive porous ceramics and the connection part connecting the segment parts are both made of a conductive material, the honeycomb structure of the present invention itself has conductivity. It has become. That is, electricity (current) flows when a voltage is applied to the honeycomb structure of the present invention. That is, the honeycomb structure of the present invention can generate heat by flowing the current. That is, when the honeycomb structure of the present invention is used as a filter (filter device) such as a DPF, the trapped PM can be removed by energizing the honeycomb structure itself to raise the temperature.

  As described above, in the honeycomb structure of the present invention, the connection portion that connects the segment portions made of conductive porous ceramics is formed of a conductive material, and a plurality of electrical connections are made through the connection portion. It has a structure in which current flows through the segment portion. That is, the current flows in the radial direction of the honeycomb structure (the direction in which the cross section expands or the direction across the cross section).

  On the other hand, as a structure often used in a conventional honeycomb structure, there is a honeycomb structure in which a plurality of segments (honeycomb segments) are bonded with a bonding material. In a conventional honeycomb structure, an insulating bonding material is used as a bonding material, and a current does not flow in the radial direction of the honeycomb structure (the direction in which the cross section expands or the direction across the cross section). For this reason, in the honeycomb structure having a conventional structure, it has been impossible to generate heat by energizing the whole.

In the honeycomb structure of the present invention, the connection portion is formed so as to connect at least part of the opposing surfaces of the pair of segment portions to be connected, and the connection portion is formed between the outer peripheral surfaces of the pair of segment portions. are non-connecting portion that is not is formed, the non-connecting portion, the filler for bonding the segment portion is disposed is filled throughout. That is, a non-connection portion that is not a connection portion is formed between the segment portions, and this non-connection portion has characteristics different from those of the connection portion. Various characteristics can be imparted to the honeycomb structure by adjusting the characteristics of the non-connection portion.

  The honeycomb structure of the present invention is formed with connecting portions and non-connecting portions. Regarding the forming conditions such as the number of connecting portions and non-connecting portions formed, the positions where they are formed, and the size formed. It is not particularly limited. That is, it can be appropriately determined depending on the use conditions when the honeycomb structure of the present invention is used.

  In the honeycomb structure of the present invention, the connecting portion is preferably provided at one or more locations in the axial direction of the honeycomb structure. By providing the connection portion at one or more locations in the axial direction, the pair of segment portions are electrically connected via the connection portion. Further, the connection portion can fix the pair of segment portions. In addition, the connection part may be either one in the axial direction or a plurality of two or more places.

  In the honeycomb structure of the present invention, the total length in the axial direction of the honeycomb structure of the connecting portion is preferably 50% or less of the length in the axial direction of the honeycomb structure. When the total length in the axial direction of the connecting portion is 50% or less of the honeycomb structure, the non-connecting portion between the segment portions is 50% or more, and when the segment portion further undergoes thermal expansion, the segment Demonstrates the effect of not restricting the deformation of the part.

  In the honeycomb structure of the present invention, when the area of the opposing surfaces of the pair of segment portions connected to the connection portions of the honeycomb structure is 100%, the total ratio of the connection portions connecting the opposing surfaces is 50%. The following is preferable. When the area of the connection part is 50% or less, the non-connection part between the segment parts becomes 50% or more, and when the segment part is further thermally expanded, the effect of not restricting the deformation of the segment part is exhibited. To do.

  In the honeycomb structure of the present invention, it is preferable that at least one of the connection portions is provided at an upstream end portion in the exhaust gas flow direction when exhaust gas purification is performed with the honeycomb structure. The connection portion becomes a path through which electricity (current) flows when a voltage is applied, and becomes a heat generating portion. Since the heat generating portion is located at the upstream end of the honeycomb structure, when the honeycomb structure is used as a filter catalyst, heat generated by the heat generation is transmitted to the entire honeycomb structure by the flow of exhaust gas, Great effect in removing PM.

  At least one of the connecting portions is preferably provided on the entire end face of the upstream end portion in the exhaust gas flow direction when exhaust gas purification is performed with the honeycomb structure. By providing at least one of the connecting portions over the entire surface of the upstream end portion of the honeycomb structure, the entire honeycomb structure can be heated, and a large effect is exhibited by removing PM.

  In the honeycomb structure of the present invention, it is preferable that the connection portion is provided only at the upstream end portion in the exhaust gas flow direction when exhaust gas purification is performed in the honeycomb structure. In this case, a gap is formed on the downstream side of the connecting portion. In particular, the downstream end portion is not restricted by the connection portion (the deformation of the segment portion is not restricted), and the honeycomb structure can be further prevented from being damaged. That is, it is preferable that there is one connecting portion, and that the connecting portion is provided on the entire end face of the upstream end portion in the exhaust gas flow direction when exhaust gas purification is performed in the honeycomb structure. .

  In the honeycomb structure of the present invention, a non-connection portion where no connection portion is formed is formed between the outer peripheral surfaces of the pair of segment portions. Various characteristics can be imparted to the honeycomb structure by adjusting the characteristics of the non-connection portion. For example, if the non-connection portion is formed of a softer material than the connection portion, the deformation of the segment portion during thermal expansion is not restricted. Moreover, the contact between segment parts can be suppressed and the damage based on the contact of a segment part can be suppressed.

In the honeycomb structure of the present invention, a filler is disposed in the non-connection portion. And a filler is filled and distribute | arranged to the whole non-connecting part. By arranging the filler in the non-connecting portions between the segment portions, the contact between the segment portions can be suppressed, and damage due to the contact of the segment portions (honeycomb structure) can be suppressed.

  The filler preferably has a lower strength than the segment portion (honeycomb structure). When the strength of the filler is low, the filler can buffer the volume change due to the deformation of the segment portion, and the thermal shock resistance of the honeycomb structure is improved.

  The material of the filler is not limited, but is preferably made of porous ceramics. Since the filler is made of porous ceramics, the filler itself can have a desired strength. More preferably, the porosity of the filler is larger than the porosity of the base material forming the segment portion. Further, the filler preferably functions as a bonding material for bonding the segment portions.

In the honeycomb structure of the present invention, the non-connecting portion be disposed only filler, be formed only in the gap, even if the filler and voids coexist, is considered to be either present The invention places only the filler . Note that it is conceivable that the gaps between the segment portions are formed so as not to connect both end portions in the axial direction of the honeycomb structure . When the gap between the segment portions connects both ends of the honeycomb structure in the axial direction, when used as a filter catalyst, exhaust gas passes through the gap, and the function as the filter catalyst is reduced. . That is, when a gap is formed in the non-connection portion, it is considered that the gap is partitioned on one side in the axial direction by the connection portion and / or the filler .

  The honeycomb structure of the present invention has one end sealing portion made of a sealing material that seals one end portion of a predetermined cell among many cells, and sealing that seals the other end portion of the remaining cells. It is preferable to have the sealing part which consists of the other end sealing part which consists of material.

  That is, the honeycomb structure of the present invention is particularly effective when used as a wall flow type filter (filter catalyst).

  In the honeycomb structure of the present invention, the cell preferably has a hexagonal cross-sectional shape in a direction perpendicular to the axial direction. When the cell has a hexagonal cross-sectional shape, thermal deformation can be further reduced. Specifically, the angle formed by the partition walls defining the cells having a hexagonal cross section is 120 degrees, and the angle formed by the partition walls is larger (gradually) than 90 degrees in the case of the conventional rectangular cross section. Thereby, the stress which generate | occur | produces at the time of a thermal deformation can be relieve | moderated more.

  Further, since the cell has a hexagonal cross-sectional shape, when the segment portion is thermally expanded and deformed in the radial direction of the honeycomb structure, the deformation direction becomes isotropic, and the deformation direction of the segment portion is not biased.

  The honeycomb structure of the present invention, the segment portion is a central segment portion having a circular outer peripheral shape located at the axis of the honeycomb structure, and a plurality of outer peripheral segment portions arranged radially on the outer periphery of the central segment portion, It is preferable to have.

  When the segment part has the central segment part and the outer peripheral segment part arranged radially, when the segment part thermally expands and deforms in the radial direction of the honeycomb structure, the deformation direction does not concentrate and the segment part The deformation direction is not biased.

  The outer peripheral segment part preferably has a fan-shaped cross section. Since the outer peripheral segment portion has a fan-shaped shape, the deformation direction of the segment portion is more uneven.

  The porous ceramic forming the segment part in the honeycomb structure of the present invention may be any material having conductivity. Having the electrical conductivity of the porous ceramic means a state in which the specific resistance is about 100 Ω · m or less. The specific resistance of the porous ceramic is not particularly limited, and is appropriately determined depending on the amount of heat generated when a voltage is applied.

  The porous ceramic forming the segment part in the honeycomb structure of the present invention is not particularly limited as long as it is a conductive material, and conventionally known porous ceramics can be used. An example of the porous ceramic is silicon carbide (SiC).

  In the honeycomb structure of the present invention, the connecting portion is not particularly limited as long as it is a conductive material, and conventionally known porous ceramics can be used. A preferable material is the same material as the material forming the segment portion, and more preferably SiC.

  The honeycomb structure of the present invention preferably has an outer peripheral material layer having a thickness of 0.5 mm or more on the outer peripheral surface in the circumferential direction. A conventionally known material can be used as the material constituting the outer peripheral material layer. For example, SiC, silica compounds, alumina compounds such as aluminum titanate, and the like can be used. Moreover, the same material as the material which forms a connection part may be sufficient. That is, porous SiC ceramics may be used. Furthermore, it is good also as a structure which mixed these materials suitably. In addition, the material known as the material constituting the outer peripheral material layer is low in conductivity (has almost no conductivity and has insulating properties), and when the outer peripheral material layer is formed of such a material. The outer peripheral material layer is formed so as not to impede application of voltage (energization) to the honeycomb structure. That is, it is preferable that the outer peripheral material layer is not formed in a portion where the electrode for applying a voltage to the honeycomb structure is electrically connected to the honeycomb structure. Furthermore, it is more preferable that the outer peripheral material layer is formed on the outer peripheral surface (at the axial position) other than the portion where the connection portion is formed (axial position).

  In addition, since the thickness of the outer peripheral material layer varies depending on the shape of the honeycomb structure, the thickness thereof cannot be determined unconditionally. More preferably, it is 0.5-5.0 mm.

  The honeycomb structure of the present invention is preferably used for a filter catalyst such as DPF. The honeycomb structure of the present invention can be used as a wall flow type filter catalyst through which exhaust gas (gas) passes through partition walls partitioning cells, and among these filter catalysts, it is particularly preferable to use as a DPF.

  When the honeycomb structure of the present invention is used as a DPF, it is preferable to support at least one of a porous oxide made of alumina or the like and a catalyst metal such as Pt, Pd, or Rh on at least the pore surfaces of the partition walls.

(Filter device)
The above honeycomb structure is preferably used for a filter catalyst. That is, the filter device of the present invention is characterized by using the honeycomb structure according to any one of the first to ninth aspects.

  The filter device of the present invention preferably includes a pair of electrodes that are electrically connected to the outer peripheral surface of the honeycomb structure, and a power supply device that applies a voltage between the pair of electrodes. By having the pair of electrodes and the power supply device, a voltage can be applied between the pair of electrodes (current can be passed), and power can be supplied to the filter device (the honeycomb structure). The honeycomb structure generates heat by the input electric power. This heat spreads to the filter device (honeycomb structure), and components such as PM collected by the filter device can be burned and removed.

  The filter device of the present invention includes a pair of electrodes electrically connected to an outer peripheral surface at an axial position where a connection portion of the honeycomb structure is formed, and a power supply device that applies a voltage between the pair of electrodes. It is preferable.

  In the filter device of the present invention, the pair of electrodes are electrically connected to the outer peripheral surface at the axial position where the connection portion of the honeycomb structure is formed, so that the honeycomb structure of the filter device (the segment portion of the honeycomb structure) And the connecting portion) can be supplied with electric power flowing between the pair of electrodes.

  The pair of electrodes are preferably connected to different segment portions, and more preferably connected to symmetrical positions with respect to the axis of the honeycomb structure. Since each of the pair of electrodes is connected to a different segment portion, a current flows between the plurality of segment portions, and the heat generation area increases. In addition, since the pair of electrodes are assembled at symmetrical positions, the current applied between the pair of electrodes flows in a direction crossing the cross section through the axis. Thereby, heat can be generated on almost the entire cross section.

  The pair of electrodes refers to a pair of electrodes through which a current flows when a voltage is applied to the filter device (honeycomb structure), and is actually electrically connected to the filter device (honeycomb structure). The number of electrode bodies may be one set or a plurality of sets.

  The power supply apparatus that applies a voltage between the pair of electrodes preferably includes an applied voltage control unit that determines and controls a voltage applied between the pair of electrodes. By having the applied voltage control means, it is possible to control the voltage applied to the filter device (honeycomb structure) (the amount of power applied). The determination of the voltage applied between the pair of electrodes is not particularly limited. Even if a predetermined voltage application pattern is used, the voltage is calculated from the measurement results such as the temperature of the filter device (honeycomb structure). Or either.

  Hereinafter, the present invention will be described using examples.

  As an example of the present invention, a honeycomb structure and a DPF (filter device) were manufactured.

Example 1
The honeycomb structure 1 of this example has a cylindrical outer shape including a honeycomb body 2 made of porous ceramics and a sealing portion (not shown) for sealing cells of the honeycomb body 2. It is a honeycomb structure. The honeycomb structure 1 of the present example is shown in FIGS. FIG. 1 shows an end face on one end side of the honeycomb structure 1 of the present embodiment, and FIG. 2 shows the configuration of the honeycomb structure 1 taken along line II (line passing through the axis) of FIG. FIG. 3 is a schematic cross-sectional view showing the configuration of the honeycomb structure 1 taken along the line II-II in FIG. 1 (a line passing through a portion off the axis perpendicular to the radial direction). One end portion is an end portion disposed on the upstream side in the exhaust gas flow direction when used as a DPF.

  The honeycomb body 2 is made of porous SiC ceramics. The honeycomb body 2 includes a segment portion 3 in which a plurality of cells 20 extending in the axial direction of the honeycomb body 2 are partitioned by partition walls 21, a connection portion 4 connecting the plurality of segment portions 3, and a plurality of segments. And a non-connection portion 5 in which the connection portion 4 is not formed between the portions 3. The honeycomb body 2 has a substantially cylindrical outer peripheral shape. The plurality of cells 20 are partitioned by partition walls 21 so as to have a regular hexagonal cross-sectional shape.

  The segment unit 3 partitions a plurality of cells 20. In the present embodiment, the segment portion 3 includes a central segment portion 30 located at the axial center of the honeycomb structure 1, and a plurality of outer peripheral segment portions 31 arranged along the circumferential direction outward in the radial direction of the central segment portion 30. It consists of. The outer peripheral surfaces of the central segment portion 30 and the outer peripheral segment portion 31 are formed in parallel with the axial direction of the honeycomb structure 1.

  The center segment portion 30 has a substantially circular outer peripheral shape in a cross section perpendicular to the axial direction. The outer peripheral segment 31 has a substantially fan-shaped outer peripheral shape in a cross section perpendicular to the axial direction. The fan shape is a shape obtained by removing a small-diameter sector from a large-diameter sector as shown in FIG. In the present embodiment, eight outer peripheral segment portions 31 are arranged. Furthermore, in this embodiment, the cell 20 of the outer peripheral segment 31 is provided with one diagonal line passing through the hexagonal center substantially parallel to the radial direction of the honeycomb body 2.

  The connecting portion 4 connects (fixes) the central segment portion 30 and the outer peripheral segment portion 31 and the outer peripheral segment portions 31 to each other. The connecting portion 4 is made of the same porous SiC ceramic as the honeycomb body 2. The connecting portion 4 is provided on the entire end surface of the end portion on the upstream side in the axial direction of the honeycomb structure 1. That is, the upstream end face in the axial direction of the honeycomb structure 1 is formed by the segment portion 3 and the connection portion 4. The connecting portion 4 is formed at 5% of the length in the axial direction of the honeycomb structure. That is, the connecting portion 4 is formed in an area corresponding to 5% of the opposing surfaces of the segment portion 3 facing each other.

  A filler 50 is provided between the central segment portion 30 and the outer peripheral segment portion 31 and between the outer peripheral segment portions 31 and the non-connecting portion 5 (downstream of the connecting portion 4) where the connecting portion 4 is not formed. Is arranged and filled throughout. In other words, only the ceramics and the filler 50 constituting the connecting portion 4 are disposed between the segment portions 3. The filler 50 filled between the segment portions 3 also functions as a bonding material for fixing the segment portions 3 to each other. The filler 50 is made of porous ceramics containing SiC as a main component and containing silica and alumina fibers. The porous ceramic constituting the filler 50 is a softer ceramic than the ceramic constituting the honeycomb body 2.

  In the honeycomb body 2, a sealing portion made of a sealing material that seals the cells 20 is formed at either one end or the other end in the axial direction of the plurality of cells 20. The sealing material is provided so that the axial length in the cell 20 is constant. The sealing material is formed in a uniformly dispersed state on the end face of the honeycomb structure 1.

  The DPF of the present embodiment is formed by arranging the honeycomb structure 1 with the end portion (one end portion) where the connection portion 4 is formed on the upstream side in the exhaust gas flow direction.

  In addition, the DPF of this example is attached to the upstream end of the honeycomb structure 1 in a state where the pair of electrode plates 7 and 7 are in contact (pressure contact). A state in which the pair of electrode plates 7 and 7 are assembled to the honeycomb structure 1 is shown in FIGS. The pair of electrode plates 7 and 7 are attached to the outer peripheral surface of the portion where the connection portion 4 of the honeycomb structure 1 is formed. Each of the pair of electrode plates 7 and 7 is electrically connected to two outer peripheral segment portions 31. The pair of electrode plates 7 and 7 are assembled at positions symmetrical with respect to the axis.

  In addition, in FIGS. 4-5 which showed DPF of a present Example, it has illustrated typically so that the structure of the honeycomb body 2 and a pair of electrode plates 7 and 7 may be understood. In FIGS. 4 to 5, in order to facilitate understanding of the arrangement of the pair of electrode plates 7 and 7 and the honeycomb structure 1, they are not in contact with each other. )doing.

  In the DPF of this embodiment, the pair of electrode plates 7 are connected to a power supply device (not shown). The power supply device applies a current (electric power) to the pair of electrode plates 7 and 7. The power supply device is a device that can determine and adjust (control) an application condition of an applied current (electric power).

(Comparative example)
This comparative example is a honeycomb structure similar to the honeycomb structure 1 of the example except that the honeycomb body 2 is formed by bonding a plurality of honeycomb bodies 80 with the bonding material 81. The end face of the honeycomb structure 1 of this comparative example is shown in FIG.

  The honeycomb structure 1 of the present comparative example has a plurality of honeycomb bodies 80 and a bonding material 81 for bonding the honeycomb bodies 80.

  In the honeycomb body 80, a plurality of cells 20 are partitioned so that a cross section perpendicular to the axial direction forms a square. The plurality of cells 20 have one end portion or the other end portion sealed with a sealing material 820 so that the end surface has a substantially checkered pattern, thereby forming a sealing portion 82. The honeycomb segment 80 is formed of porous SiC ceramics that form the segment portion 3 in the embodiment.

  The bonding material 81 is formed between the entire surfaces between the opposing surfaces of the adjacent honeycomb bodies 80, and bonds the adjacent honeycomb bodies 80 together. The bonding material 81 is made of a ceramic containing SiC and silica as main components (including a silica-rich state).

  In the honeycomb structure 1 of the present comparative example, 16 honeycomb bodies 80 having a square cross-sectional shape perpendicular to the axial direction are joined with a joining material 81, and the joined body is cut with an electric saw to obtain a substantially cylindrical shape. Thus, the honeycomb body 2 is formed. That is, in the honeycomb body 2, among the honeycomb bodies 80, the four honeycomb bodies 80 positioned in the vicinity of the axial center have a square outer peripheral shape, and the remaining 12 honeycomb bodies 80 positioned in the outer peripheral portion are The surface which becomes the outer peripheral surface of the honeycomb body 2 has a molded shape.

  This comparative example has the same configuration as the honeycomb structure 1 of the example except that the configuration of the honeycomb body 2 is different.

(Evaluation)
As an evaluation of the honeycomb structure (DPF) of Example 1, voltage was applied (power was supplied) between the pair of electrode plates 7 and 7 assembled in the DPF of Example 1, and the temperature change of the honeycomb structure 1 was measured. It was measured.

  First, by adjusting the power supply device, the electric current that flows when a voltage is applied is made constant at 10 A, and the power of the DPF of the example is input, and the temperature of the upstream end face where the connection part 4 of the honeycomb structure is formed Was measured. The measurement results are shown in FIG. FIG. 7 also shows the measurement result of the voltage when a constant current of 10 A is flowing.

  Next, electric power with a constant applied voltage of 20 V was applied to the DPF of Example 1, and the temperature of the end face on the upstream side where the connection portion 4 of the honeycomb structure was formed was measured. The measurement results are shown in FIG. FIG. 8 also shows the measurement results of current when a constant voltage of 20 V is applied.

  Further, power satisfying the maximum value of the applied voltage of 40 V and the maximum value of the applied current of 50 A was applied to the DPF of Example 1, and the temperature of the end face on the upstream side where the connection part 4 of the honeycomb structure was formed was measured. . The measurement results are shown in FIG.

  As shown in FIGS. 7 to 9, in the DPF of Example 1, since both the segment part 3 and the connection part 4 have conductivity, the end face is traversed at the upstream end part. Thus, it was confirmed that the current flowed and the upstream end portion generated heat. Moreover, in the DPF of Example 1, it was confirmed that the temperature of the end portion on the upstream side was increased in proportion to the length of time during which power was applied between the pair of electrode plates 7 and 7.

  In this evaluation, the same electric power as in Example 1 was applied to the DPF of the comparative example, but the honeycomb segment 80 is made of the same material as the honeycomb body 2 of the honeycomb structure 1 of Example 1, so that the conductivity is high. However, the bonding material 81 has electrical insulation (resistance value cannot be measured), and current did not flow between the pair of electrodes. That is, in the comparative example, no heat generation of the honeycomb structure itself was observed.

  As described above, the honeycomb structure 1 (DPF) of Example 1 has a configuration in which the conductive segment portion 3 is connected by the connection portion 4 having conductivity. That is, the honeycomb structure 1 (honeycomb body 2) itself has conductivity. As a result, when a voltage is applied between the pair of electrode plates 7 and 7 assembled to the honeycomb structure 1, a current flows, and the honeycomb structure 1 (honeycomb body 2) itself generates heat due to the flowing current. Due to this heat generation, when used as a DPF, the collected PM can be burned and removed.

  In contrast, in the honeycomb structure 1 (DPF) of the comparative example, no current flows between the pair of electrode plates 7 and 7. For this reason, when using as a DPF, another device is required to burn and remove the collected PM.

  That is, it was found that the honeycomb structure 1 (DPF) of Example 1 was a honeycomb structure excellent in reproducibility because combustion removal of the collected PM could be achieved with a simple structure.

  Further, in the honeycomb structure 1 (DPF) of Example 1, the non-connecting portion 5 filled with the filler 50 is formed between the segment portions 30 and 31 at the end portion on the downstream side in the axial direction. Even if the segment portions 30 and 31 are thermally expanded, the segment portions 30 and 31 are restricted from contacting each other with the filler 50 interposed therebetween. That is, the segment portion is prevented from being damaged.

  As described above, the honeycomb structure 1 (DPF) of Example 1 is a honeycomb structure having excellent regenerative properties and suppressing damage due to thermal deformation.

(Modification of Example 1)
(First variation)
This embodiment is a honeycomb structure 1 (DPF) having the same configuration as that of the honeycomb structure 1 (DPF) of the first embodiment except that the length of the connecting portion 4 in the axial direction is different.

  As shown in FIGS. 10 to 11, the honeycomb structure 1 (DPF) of the present embodiment has a form in which the connection portion 4 is formed with 50% of the length in the axial direction. FIG. 10 is a diagram showing a cross-sectional configuration similar to FIG. 2, and FIG. 11 is a diagram illustrating a cross-sectional configuration similar to FIG.

  Also in this embodiment, like the honeycomb structure of Example 1, it has a structure that can be energized, and the same effect as the honeycomb structure of Example 1 was exhibited.

(Second variant)
The present embodiment is a honeycomb structure 1 (DPF) having the same configuration as the honeycomb structure 1 (DPF) of the first embodiment except that the position of the connecting portion 4 in the axial direction is different.

  As shown in FIGS. 12 to 13, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portion 4 is formed at the central portion in the axial direction. 12 is a diagram showing a cross-sectional configuration similar to FIG. 2, and FIG. 13 is a diagram illustrating a cross-sectional configuration similar to FIG. In this embodiment, the length of the connecting portion 4 in the axial direction is 5% (in each of the following embodiments, the length of one connecting portion 4 in the axial direction is 5% unless otherwise specified. is there.). In the present embodiment, the non-connecting portion 5 is formed between the segment portions 30 and 31 on the upstream side and the downstream side of the connecting portion 4. Furthermore, in this embodiment, the pair of electrode plates 7 and 7 are assembled at the central portion in the axial direction of the honeycomb structure 1 in which the connection portions 4 are formed.

  Also in this embodiment, like the honeycomb structure of Example 1, it has a structure that can be energized, and the same effect as the honeycomb structure of Example 1 was exhibited.

(Third variant)
In this embodiment, the honeycomb structure having the same configuration as that of the honeycomb structure 1 (DPF) of Example 1 except that the connection portion 4 is formed at the center portion (axial center portion) of the end face of the upstream end portion. Body 1 (DPF).

  In the honeycomb structure 1 (DPF) of the present embodiment, as shown in FIGS. 14 to 16, the connecting portion 4 is between the central segment portion 30 and the outer peripheral segment portion 31 and between the outer peripheral segment portions 31. , Formed on a part of the inner diameter side. FIG. 14 schematically shows an end face of the honeycomb structure 1 of the present embodiment, FIG. 15 schematically shows a cross-sectional configuration similar to FIG. 2, and FIG. 16 schematically shows a cross-sectional configuration similar to FIG. . A non-connecting portion 5 where the connecting portion 4 is not formed is filled with a filler 50. The connection part 4 formed between the outer periphery segment parts 31 is formed to the range where the position of the outer periphery segment part 31 in the radial direction is 50%. The part located between the outer peripheral segment parts 31 and outside the connecting part 4 in the radial direction is the non-connecting part 5, and is filled with the filler 50.

  Also in this embodiment, like the honeycomb structure of Example 1, it has a structure that can be energized, and the same effect as the honeycomb structure of Example 1 was exhibited.

(Fourth modification)
The present embodiment is a honeycomb structure 1 (DPF) having the same configuration as that of the honeycomb structure 1 (DPF) of Example 1 except that the connection portion 4 is formed other than the upstream end portion. .

  As shown in FIGS. 17 to 18, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portions 4 are formed at the upstream end portion in the axial direction and the central portion in the axial direction. FIG. 17 schematically shows a cross-sectional configuration similar to that of FIG. 2, and FIG. 18 schematically shows a cross-sectional configuration similar to that of FIG. In the present embodiment, the lengths (the lengths in the axial direction) of the connecting portions 4 formed at the upstream end portion and the central portion in the axial direction are each 5%, and the total length is the honeycomb structure. 1 is set to be 50% or less of the length in the axial direction.

  Also in this embodiment, like the honeycomb structure of Example 1, it has a structure that can be energized, and the same effect as the honeycomb structure of Example 1 was exhibited.

(5th modification)
The present embodiment is a honeycomb structure 1 (DPF) having the same configuration as the honeycomb structure 1 (DPF) of the fourth modified embodiment except that a plurality of connection portions 4 are formed in the central portion in the axial direction.

  In the honeycomb structure 1 (DPF) of the present embodiment, as shown in FIGS. 19 to 20, the connection portion 4 is upstream with an upstream end portion in the axial direction, a central portion in the axial direction, and an axial length. It is the form formed in the position of 1/4 from the edge part of the side. FIG. 19 schematically shows a cross-sectional configuration similar to FIG. 2, and FIG. 20 schematically illustrates a cross-sectional configuration similar to FIG. In the present embodiment, the lengths (the lengths in the axial direction) of the connecting portions 4 formed at the upstream end portion and the central portion in the axial direction are each 5%, and the total length is the honeycomb structure. 1 is set to be 50% or less of the length in the axial direction.

  Also in this embodiment, the structure can be energized similarly to the honeycomb structures of Example 1 and the fourth modification, and the same effects as those of the honeycomb structures of Example 1 and the fourth modification are exhibited.

(Sixth variation)
This embodiment has the same configuration as that of the honeycomb structure 1 (DPF) of the fourth modification except that the connection portion 4 formed at the central portion in the axial direction is formed only at the central portion (axial center portion). Honeycomb structure 1 (DPF).

  As shown in FIGS. 21 to 22, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portions 4 are formed at the upstream end portion in the axial direction and the central portion in the axial direction. And the connection part 4 formed in the center part of the axial direction is formed with the form similar to the connection part 4 of 3rd Embodiment. FIG. 21 schematically shows a cross-sectional configuration similar to FIG. 2, and FIG. 22 schematically illustrates a cross-sectional configuration similar to FIG.

  Also in this embodiment, the structure can be energized similarly to the honeycomb structures of Example 1 and the fourth modification, and the same effects as those of the honeycomb structures of Example 1 and the fourth modification are exhibited.

(Seventh variation)
In the present embodiment, a honeycomb structure having the same configuration as that of the honeycomb structure 1 (DPF) according to the sixth modified embodiment, except that the connection portion 4 is formed at the center portion (axial center portion) at the upstream end portion. 1 (DPF).

  As shown in FIGS. 23 to 24, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portions 4 are formed at the end portion on the upstream side in the axial direction and the central portion in the axial direction. And both of the two connection parts 4 and 4 are formed in the form similar to the connection part 4 of 3rd Embodiment. FIG. 23 schematically shows a cross-sectional configuration similar to FIG. 2, and FIG. 24 schematically illustrates a cross-sectional configuration similar to FIG.

  Also in this embodiment, the structure can be energized similarly to the honeycomb structures of Example 1 and the sixth modification, and the same effects as those of the honeycomb structures of Example 1 and the sixth modification are exhibited.

(Eighth variation)
In the present embodiment, the honeycomb structure according to the fourth modified embodiment is formed except that the connecting portion 4 formed in the central portion in the axial direction is formed only on a part of the opposing surfaces of the opposing segment portions 3 and 3. The honeycomb structure 1 (DPF) has the same configuration as the body 1 (DPF).

  As shown in FIGS. 25 to 26, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portions 4 are formed at the upstream end portion in the axial direction and the central portion in the axial direction. And the connection part 4 formed in the center part of the axial direction is 50% of the width | variety (the length of the circumferential direction or the length of radial direction) of the opposing surface in the opposing surface between the segment parts 3 and 3 which opposes. It is formed with a corner size. More specifically, the opposing surfaces of the central segment portion 30 and the outer peripheral segment portion 31 are formed to be a square having a length that is 50% of the length in the circumferential direction. The opposing surfaces of the outer peripheral segment portions 31 and 31 are formed to be a square having a length that is 50% of the length in the radial direction. FIG. 26 is a diagram schematically showing a configuration in a cross section taken along line III-III in FIG.

  Also in this embodiment, the structure can be energized similarly to the honeycomb structures of Example 1 and the fourth modification, and the same effects as those of the honeycomb structures of Example 1 and the fourth modification are exhibited.

(9th modification)
This embodiment is a honeycomb according to the fourth modified embodiment except that a plurality of connection portions 4 formed at the central portion in the axial direction are formed only on a part of opposing surfaces of the opposing segment portions 3 and 3. The honeycomb structure 1 (DPF) has the same configuration as the structure 1 (DPF).

  In the honeycomb structure 1 (DPF) of the present embodiment, as shown in FIG. 27, the connection portion 4 is located at an end portion on the upstream side in the axial direction, a center portion in the axial direction, and a 1/4 position from the upstream side. Is formed. And the connection part 4 formed in the center part of an axial direction and the position of 1/4 from the upstream is the opposing surface between the segment parts 3 and 3 which opposes similarly to the connection part of said 8th modification. It is formed in a square with a length of 50% of the width of. 27 is a cross-sectional view similar to FIG.

  Also in this embodiment, the structure can be energized similarly to the honeycomb structures of Example 1 and the fourth modification, and the same effects as those of the honeycomb structures of Example 1 and the fourth modification are exhibited.

(10th modification (reference form) )
This embodiment has the same configuration as that of the honeycomb structure 1 (DPF) of Example 1 except that the non-connection portion 5 located on the downstream side of the connection portion 4 is not the filler 50 but the gap 51. Honeycomb structure 1 (DPF).

  As shown in FIGS. 28 to 29, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portion 4 is formed on the entire upstream end of the honeycomb structure 1 in the axial direction. . In this embodiment, the non-connection portion 5 on the downstream side of the connection portion 4 is a gap 51. That is, the outer peripheral surface of the segment part 3 is exposed on the downstream side of the connection part 4. FIG. 28 schematically shows a cross-sectional configuration similar to FIG. 2, and FIG. 29 schematically illustrates a cross-sectional configuration similar to FIG.

  Also in this embodiment, like the honeycomb structure of Example 1, it has a structure that can be energized, and the same effect as the honeycomb structure of Example 1 was exhibited.

  Furthermore, in this embodiment, a gap 51 is formed as the non-connection portion 5 between the segment portions 30 and 31. In this configuration, even if the segment portions 30 and 31 are thermally expanded, the deformation of the segment portions 30 and 31 is not restricted. That is, the effect of suppressing breakage of the segment portion is exhibited.

(Eleventh modification (reference form) )
In the present embodiment, a honeycomb having the same configuration as that of the honeycomb structure 1 (DPF) of Example 1 except that the non-connection portion 5 located on the downstream side of the connection portion 4 includes the filler 50 and the void 51. Structure 1 (DPF).

  As shown in FIGS. 30 to 31, the honeycomb structure 1 (DPF) of the present embodiment has a configuration in which the connection portion 4 is formed on the entire upstream end of the honeycomb structure 1 in the axial direction. . 30 schematically illustrates a cross-sectional configuration similar to that of FIG. 2, and FIG. 31 schematically illustrates a cross-sectional configuration similar to that of FIG. In this embodiment, the non-connection portion 5 on the downstream side of the connection portion 4 includes the filler 50 filled on the upstream side, and the downstream end of the honeycomb structure 1 on the downstream side of the filler 50. It has a form in which a gap 51 is formed. That is, the filler 50 is filled on the downstream side of the connecting portion 4 and the outer peripheral surface of the segment portion 3 is exposed on the downstream side.

  Also in this embodiment, like the honeycomb structure of Example 1, it has a structure that can be energized, and the same effect as the honeycomb structure of Example 1 was exhibited.

(Twelfth modification)
The present embodiment is a honeycomb structure 1 (DPF) having the same configuration as the honeycomb structure 1 (DPF) of the first embodiment except that the shapes of the segment portions 30 and 31 and the shape of the cells 20 are different.

  As shown in FIG. 32, the honeycomb structure 1 (DPF) of the present embodiment has a form in which the segment portions 3 and the cells 20 are formed to have a square cross section. In the present embodiment, the segment portion 3 has a shape that substantially matches the honeycomb segment 80 of the comparative example.

  In this embodiment as well, the same structure as that of the honeycomb structure of Example 1 can be energized, and even if the shape of the segment part 3 (honeycomb body 2) is different, it is the same as that of the honeycomb structure of Example 1. The effect was demonstrated.

  Furthermore, also in this embodiment, the connection portion 4 may be formed in the same manner as each modification.

(Example 2)
The present example is a honeycomb structure 1 (DPF) having the same configuration as the honeycomb structure 1 of Example 1, except that the honeycomb structure 1 has the outer peripheral material layer 6. The honeycomb structure 1 of the present example is shown in FIGS. FIG. 33 schematically shows a configuration of an end face similar to that of FIG. 4, and FIG. 34 schematically shows a configuration of a cross section similar to FIG.

  In the present embodiment, the outer peripheral material layer 6 is provided on the outer periphery of the honeycomb body 2.

  The outer peripheral material layer 6 is a ceramic layer mainly containing SiC and silica formed on the outer peripheral surface of the honeycomb body 2 with a uniform thickness (including a silica-rich state). The outer peripheral material layer 6 had a thickness (a thickness in the radial direction) of 0.5 mm.

  The outer peripheral material layer 6 is provided on the outer peripheral surface of a portion other than the portion where the connection portion 4 is formed (portion where the connection portion 4 is not formed).

  The pair of electrode plates 7 and 7 are assembled on the outer peripheral surface of the honeycomb structure 1 so as to be electrically connected to the segment portions 31 and 31.

  In the honeycomb structure 1 of the present embodiment, the outer peripheral material layer 6 is formed on the outer peripheral surface other than the portion to which the pair of electrode plates 7 and 7 are connected, and current conduction between the pair of electrode plates 7 and 7 is hindered. Not. That is, the same effect as the honeycomb structure 1 of Example 1 is exhibited.

  Further, in the honeycomb structure 1 of the present example, the outer peripheral material layer 6 is formed on the outer peripheral surface other than the portion where the pair of electrode plates 7 and 7 are connected, so that the honeycomb body 2 is not exposed and is handled at the time of handling. The honeycomb body 2 is prevented from being damaged.

  Also in the present embodiment, the connecting portion 4 may be formed in the same manner as each modification.

1: Honeycomb structure 2: Honeycomb body 20: Cell 21: Partition wall 3: Segment part 30: Central segment part 31: Peripheral segment part 4: Connection part 5: Non-connection part 50: Filler 51: Air gap 6: Peripheral material layer 7: Electrode plate 80: Honeycomb segment 81: Bonding material 82: Sealing part 820: Sealing material

Claims (11)

A segment portion made of conductive porous ceramics and partitioned in a plurality of cells extending in the axial direction; and a connection portion connecting the plurality of segment portions;
A honeycomb structure having
The connection portion is made of a conductive material, and is formed so as to connect at least a part of the opposing surfaces of the pair of segment portions to be connected,
Between the outer peripheral surfaces of the pair of segment portions, a non-connection portion where the connection portion is not formed is formed,
The non-connecting portion, the honeycomb structure, wherein a filler joining the segment portion is disposed is filled throughout.   The honeycomb structure according to claim 1, wherein the connecting portion is provided at one or more locations in the axial direction of the honeycomb structure.   The honeycomb structure according to any one of claims 1 to 2, wherein a total length of the connecting portions in the axial direction of the honeycomb structure is 50% or less of an axial length of the honeycomb structure.   The honeycomb according to any one of claims 1 to 3, wherein at least one of the connection portions is provided at an upstream end portion in a flow direction of exhaust gas when exhaust gas purification is performed with the honeycomb structure. Structure.   5. The honeycomb structure according to claim 4, wherein at least one of the connection portions is provided on the entire end face of the upstream end portion in the exhaust gas flow direction when exhaust gas purification is performed in the honeycomb structure. . One end sealing portion made of a sealing material for sealing one end portion of a predetermined cell among the plurality of cells,
The other end sealing portion made of a sealing material for sealing the other end portion of the remaining cells,
The honeycomb structure according to any one of claims 1 to 5, wherein the honeycomb structure has a sealing portion.   The honeycomb structure according to any one of claims 1 to 6, wherein the cell has a hexagonal cross-sectional shape in a direction perpendicular to the axial direction. The segment part is
A central segment portion having a circular outer peripheral shape located at the axial center of the honeycomb structure;
A plurality of outer peripheral segment portions arranged radially on the outer periphery of the central segment portion;
A honeycomb structure according to any one of claims 1 to 7.   The honeycomb structure according to claim 8, wherein the outer peripheral segment portion has a fan-shaped cross section.   A filter device comprising the honeycomb structure according to any one of claims 1 to 9. A pair of electrodes electrically connected to the outer peripheral surface at the axial position where the connection part of the honeycomb structure is formed;
A power supply device for applying a voltage between the pair of electrodes;
The filter device according to claim 10.

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