Vehicle air-conditioning system

Abstract

To provide a vehicle air-conditioning system capable of effectively utilizing heated air while selectively removing moisture released into the air during regeneration of a dehumidifying material (dehumidifying layer).SOLUTION: A vehicle air-conditioning system 100 comprises: a dehumidifying device 10 comprising a honeycomb structure in which partition walls are composed of a material having PTC characteristics, a pair of electrodes, and a dehumidifying layer formed on a surface of each of the partition walls; a power source 20 for applying voltage to the pair of electrodes; an inflow pipe 30 for allowing air from a cabin or from outside a vehicle to flow into the dehumidifying device 10; a first outflow pipe 40 for returning the air dehumidified by the dehumidifying device 10 to the cabin; a second outflow pipe 50 for allowing the air containing moisture released by regeneration of the dehumidifying device 10 to flow therethrough; and a switching valve 60 capable of switching a flow of the air to the first outflow pipe 40 or the second outflow pipe 50. A separator 70 capable of separating the moisture contained in the air by centrifugation is disposed inside the second outflow pipe 50.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle air conditioning system. [Background technology]

[0002] There is an increasing demand for improved cabin environments in various vehicles such as automobiles. Specific demands include reducing CO2 in the cabin to suppress drowsiness in the driver, controlling humidity in the cabin, and removing odorous components, allergy-inducing components, and other harmful volatile components in the cabin. Ventilation is an effective measure to meet such demands, but ventilation causes a large loss of heater energy in winter, leading to a decrease in energy efficiency in winter. In particular, electric vehicles (BEVs: Battery Electric Vehicles) have the problem that the energy loss significantly reduces the driving range.

[0003] As a method for solving the above problem, Patent Documents 1 and 2 disclose a vehicle air conditioning system in which components to be removed, such as moisture (water vapor) and CO2 in the air in the vehicle cabin, are captured by a functional material such as an adsorbent, and then the components to be removed are reacted or desorbed by heating and released outside the vehicle, thereby regenerating the functional material. In such a vehicle air conditioning system, it is required that the air and the functional material have as much contact as possible in order to ensure the capture performance of the components to be removed, and that the functional material be heated to a predetermined temperature in order to promote the regeneration of the functional material. Regeneration is performed, for example, by a method of removing the components to be removed adsorbed on the functional material by an oxidation reaction, or a method of desorbing and discharging the components to be removed adsorbed on the functional material, but in either case, it is necessary to heat the functional material to an appropriate temperature depending on the type of the adsorbed components to be removed.

[0004] On the other hand, Patent Document 3 discloses a heater element having a columnar honeycomb structure having an outer peripheral wall and partition walls disposed inside the outer peripheral wall and partitioning a plurality of cells that form a flow path from a first end face to a second end face, the partition walls having PTC characteristics, an average thickness of the partition walls being 0.13 mm or less, and an opening ratio at the first end face and the second end face being 0.81 or more. This heater element is used for heating the vehicle interior, and since the heating area can be increased by having a honeycomb structure, it is an efficient heating means. Therefore, it is considered that using such a heater element as a carrier for a functional material can contribute to shortening the regeneration time of the functional material. In particular, since this heater element can be heated by current and has PTC characteristics, it is considered that it can easily heat the functional material while suppressing excessive heat generation and suppressing thermal deterioration of the functional material. In addition, since the risk of excessive temperature is avoided, safety can be ensured even if the initial resistance is set small and the heating rate is increased, and the temperature can be raised in a short time. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-104774 A [Patent Document 2] JP 2020-111282 A [Patent Document 3] International Publication No. 2020 / 036067 Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional vehicle air conditioning systems, the functional material is heated during regeneration processing to cause the components to be removed that are captured in the functional material to react or desorb, and are then released outside the vehicle together with the heated air, resulting in a waste of thermal energy. However, when the component to be removed is moisture, a dehumidifying material is used as the functional material, and it is thought that if the moisture released into the air during the regeneration processing of the dehumidifying material can be selectively removed, the heated air can be effectively used for heating, etc.

[0007] The present invention has been made to solve the above-mentioned problems, and aims to provide a vehicle air conditioning system that can effectively utilize heated air while selectively removing moisture released into the air during the regeneration process of a desiccant (dehumidification layer). [Means for solving the problem]

[0008] The present inventors have conducted extensive research into a vehicle air conditioning system equipped with a dehumidifying device in which a dehumidifying layer is formed on the partition walls of a honeycomb structure, and have found that the above-mentioned problems can be solved by providing a separator capable of separating moisture contained in the air by centrifugal separation in a pipe through which air containing moisture released by the regeneration process of the dehumidifying device flows, and by merging this pipe with a pipe for returning air to the passenger compartment downstream of the separator, thereby completing the present invention. That is, the present invention is exemplified as follows.

[0009] (1) A dehumidifying device including: a honeycomb structure having an outer peripheral wall and partition walls disposed inside the outer peripheral wall and defining a plurality of cells that serve as flow paths extending from a first end face to a second end face, the partition walls being made of a material having a PTC characteristic; a pair of electrodes provided on the first end face and the second end face; and a dehumidifying layer formed on a surface of the partition walls; A power source for applying a voltage to the pair of electrodes; an inlet pipe for introducing air from a vehicle interior or from outside the vehicle into the dehumidifying device; a first outlet pipe for returning the air dehumidified by the dehumidifying device to the vehicle compartment; A second outlet pipe through which the air containing moisture released by the regeneration process of the dehumidification device flows; a switching valve provided at a branching portion between the first outlet pipe and the second outlet pipe and capable of switching the flow of the air to the first outlet pipe or the second outlet pipe; Equipped with a separator capable of separating moisture contained in the air by centrifugation is disposed in the second outflow pipe; The second outlet pipe joins the first outlet pipe downstream of the separator.

[0010] (2) The vehicle air conditioning system according to (1), wherein the second outlet pipe is provided with a branch discharge pipe for discharging the moisture separated by the separator.

[0011] (3) The second outflow pipe has a horizontal portion and an inclined portion inclined vertically upward toward the downstream side, The vehicle air conditioning system according to (2), wherein the separator is disposed in the inclined portion, and the branch discharge pipe is provided at a boundary between the horizontal portion and the inclined portion.

[0012] (4) The vehicle air conditioning system according to (1), wherein the separator is a cyclone type water separator.

[0013] (5) The switching valve is a differential pressure valve capable of switching the flow of the air to the first outlet pipe or the second outlet pipe, a first fan that controls the differential pressure valve to switch the air flow to the first outlet pipe; a second fan that controls the differential pressure valve to switch the air flow to the second outlet pipe; The vehicle air conditioning system according to any one of (1) to (4), further comprising:

[0014] (6) The vehicle air conditioning system according to any one of (1) to (5), wherein at the branching portion between the first outlet pipe and the second outlet pipe, the second outlet pipe has a double pipe structure disposed inside the first outlet pipe.

[0015] (7) The vehicle air conditioning system according to (5) or (6), wherein the first fan is disposed in the inlet pipe.

[0016] (8) The vehicle air conditioning system according to any one of (5) to (7), wherein the second fan is disposed in the second outlet pipe.

[0017] (9) The vehicle air conditioning system according to any one of (1) to (8), wherein the material having a PTC characteristic is mainly composed of barium titanate.

[0018] (10) The vehicle air conditioning system according to any one of (1) to (9), wherein the dehumidifying layer contains an adsorbent having a function of adsorbing at least one selected from carbon dioxide and a volatile component, and / or a catalyst.

[0019] (11) a dehumidification mode in which the switching valve is controlled to switch the flow of the air to the first outflow pipe to dehumidify the vehicle interior; a regeneration mode in which a voltage is applied to the pair of electrodes of the dehumidifying device and the switching valve is controlled to switch the flow of the air to the second outflow pipe to perform a regeneration process of the dehumidifying layer; The vehicle air conditioning system according to any one of (1) to (10), further comprising a control unit capable of executing the above.

[0020] (12) The vehicle air conditioning system described in (11) further includes a detection unit capable of detecting fogging of a glass in the vehicle compartment, and the control unit executes the regeneration mode when fogging of the glass is detected, and executes the dehumidification mode when fogging of the glass is not detected.

[0021] (13) The vehicle air conditioning system according to (12), wherein the detection unit detects fogging of the glass based on a temperature and a humidity inside the vehicle cabin. Effect of the Invention

[0022] According to the present invention, it is possible to provide a vehicle air conditioning system that can effectively utilize heated air while selectively removing moisture released into the air during the regeneration process of a dehumidifying material (dehumidifying layer). [Brief description of the drawings]

[0023] [Figure 1] 1 is a schematic configuration diagram of a vehicle air conditioning system according to an embodiment of the present invention; [Figure 2A] 1 is a schematic diagram of a cross section parallel to a flow path direction of a dehumidifying device used in a vehicle air conditioning system according to an embodiment of the present invention. [Figure 2B] 2B is a schematic cross-sectional view of the dehumidification device of FIG. 2A taken along line aa'. FIG. [Diagram 3] FIG. 4 is a schematic configuration diagram of a vehicle air conditioning system according to another embodiment of the present invention. [Figure 4A] FIG. 4 is a partial enlarged view showing the state of the differential pressure valve in a dehumidification mode. [Figure 4B] FIG. 4 is a partial enlarged view showing the state of the differential pressure valve in a regeneration mode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The vehicle air conditioning system of the present invention includes a honeycomb structure having an outer peripheral wall and partition walls arranged inside the outer peripheral wall and defining a plurality of cells that serve as flow paths extending from a first end face to a second end face, the partition walls being made of a material having a PTC (Positive Temperature Coefficient) characteristic, a dehumidifying device including a pair of electrodes provided on the first end face and the second end face, and a dehumidifying layer formed on a surface of the partition walls; a power source for applying a voltage to the pair of electrodes; an inlet pipe for introducing air from the vehicle interior or outside the vehicle into the dehumidifying device; a first outlet pipe for returning air dehumidified by the dehumidifying device to the vehicle interior; a second outlet pipe through which air containing moisture released by a regeneration process of the dehumidifying device flows; and a switching valve provided at a branch point between the first outlet pipe and the second outlet pipe and capable of switching the flow of air to the first outlet pipe or the second outlet pipe; a separator capable of separating moisture contained in the air by centrifugal separation is arranged in the second outlet pipe; and the second outlet pipe merges with the first outlet pipe downstream of the separator. With this configuration, the vehicle air conditioning system of the present invention can selectively remove moisture released into the air during the regeneration process using the separator. The heated air can then be returned to the vehicle interior, where it can be effectively used for heating, etc. This can improve energy efficiency, particularly in the winter.

[0025] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments, and it should be understood that modifications and improvements to the following embodiments, which are made based on the ordinary knowledge of a person skilled in the art, fall within the scope of the present invention, without departing from the spirit of the present invention.

[0026] The vehicle air conditioning system according to the embodiment of the present invention is used in various vehicles such as automobiles. Examples of the vehicle include, but are not limited to, automobiles and trains. Examples of the vehicle include, but are not limited to, gasoline vehicles, diesel vehicles, gas-fueled vehicles using CNG (compressed natural gas) or LNG (liquefied natural gas), fuel cell vehicles, electric vehicles, and plug-in hybrid vehicles. The vehicle air conditioning system according to the embodiment of the present invention is particularly suitable for use in vehicles that do not have an internal combustion engine, such as electric vehicles and trains.

[0027] Fig. 1 is a schematic diagram of a vehicle air conditioning system according to an embodiment of the present invention. Fig. 2A is a schematic diagram of a cross section parallel to the flow path direction of a dehumidifying device used in the vehicle air conditioning system according to an embodiment of the present invention. Fig. 2B is a schematic diagram of a cross section of the dehumidifying device of Fig. 2A taken along line a-a'.

[0028] 1, a vehicle air conditioning system 100 according to an embodiment of the present invention includes a dehumidifying device 10, a power source 20, an inlet pipe 30, a first outlet pipe 40, a second outlet pipe 50, a switching valve 60, and a separator 70. The vehicle air conditioning system 100 may further include a ventilator 80 for circulating air through the pipes (the inlet pipe 30, the first outlet pipe 40, and the second outlet pipe 50), and a control unit 90 for controlling the power source 20, the switching valve 60, the separator 70, the ventilator 80, etc.

[0029] As shown in FIGS. 2A and 2B, the dehumidifying device 10 includes a honeycomb structure 15 having an outer peripheral wall 11 and partition walls 14 disposed inside the outer peripheral wall 11 and defining a plurality of cells 13 that serve as flow paths extending from a first end face 12a to a second end face 12b, a pair of electrodes 16a, 16b provided on the first end face 12a and the second end face 12b, and a dehumidifying layer 17 formed on the surface of the partition wall 14. The power source 20 can apply a voltage to the pair of electrodes 16a, 16b. The inlet pipe 30 can allow air from the vehicle interior or outside the vehicle to flow into the dehumidifying device 10. The first outlet pipe 40 can return the air dehumidified by the dehumidifying device 10 to the vehicle interior. The second outlet pipe 50 can circulate air containing moisture released by the regeneration process of the dehumidifying device 10. The switching valve 60 is provided at the branch point of the first outlet pipe 40 and the second outlet pipe 50, and can switch the flow of air to the first outlet pipe 40 or the second outlet pipe 50. The separator 70 can separate moisture contained in the air by centrifugation, and is disposed in the second outlet pipe 50. The second outlet pipe 50 merges with the first outlet pipe 40 downstream of the separator 70.

[0030] In the vehicle air conditioning system 100 having the above-mentioned configuration, air from the vehicle interior or outside the vehicle flows into the dehumidifying device 10 through the inlet pipe 30, and moisture in the air is captured (removed) in the dehumidifying layer 17 while passing through the dehumidifying device 10. Then, the air with reduced moisture returns to the vehicle interior through the first outlet pipe 40. The mode in which moisture contained in the air from the vehicle interior or outside the vehicle is removed in this manner and returned to the vehicle interior is called a dehumidifying mode. On the other hand, the performance of the dehumidification layer 17 gradually decreases as the amount of moisture captured increases, so the dehumidification layer 17 must be regenerated. The regeneration process of the dehumidification layer 17 is performed by applying a voltage to the pair of electrodes 16a, 16b and heating the honeycomb structure 15. Since the dehumidification layer 17 is directly heated by heating the honeycomb structure 15, the moisture captured in the dehumidification layer 17 is efficiently desorbed or reacted and released from the dehumidification layer 17. The released air flows through the second outlet pipe 50 into the separator 70. The separator 70 selectively separates (removes) the moisture in the air and discharges the heated air. The heated air passes through the second outlet pipe 50, merges with the first outlet pipe 40, and returns to the vehicle cabin. The mode in which the regeneration process of the dehumidification layer 17 is performed in this manner is called a regeneration mode.

[0031] Each component of the vehicle air conditioning system 100 will now be described in detail.

[0032] (1. Dehumidifying device 10) 2A and 2B, the dehumidifying device 10 includes a honeycomb structure 15 having an outer peripheral wall 11, partition walls 14 disposed inside the outer peripheral wall 11 and defining a plurality of cells 13 that serve as flow paths extending from a first end face 12a to a second end face 12b, a pair of electrodes 16a, 16b provided on the first end face 12a and the second end face 12b, and a dehumidifying layer 17 formed on the surface of the partition wall 14. Furthermore, the dehumidifying device 10 may further include terminals 18 connected to the pair of electrodes 16a, 16b, as necessary.

[0033] (1-1. Honeycomb structure 15) The shape of the honeycomb structure 15 is not particularly limited. For example, the outer shape of a cross section perpendicular to the flow path direction (the direction in which the cells 13 extend) of the honeycomb structure 15 can be a polygon such as a quadrangle (rectangle, square), pentagon, hexagon, heptagon, or octagon, a circle, or an oval shape (egg, ellipse, oval, rounded rectangle, etc.). The end faces (first end face 12a and second end face 12b) have the same shape as the cross section. When the cross section and the end faces are polygonal, the corners may be chamfered.

[0034] The shape of the cells 13 is not particularly limited, but may be a polygon such as a square, pentagon, hexagon, heptagon, or octagon, a circle, or an oval in a cross section perpendicular to the flow path direction of the honeycomb structure 15. These shapes may be used alone or in combination of two or more. Among these shapes, a square or hexagon is preferable. By providing cells 13 of such a shape, the pressure loss during air flow can be reduced.

[0035] The honeycomb structure 15 may be a honeycomb bonded body having a plurality of honeycomb segments and a bonding layer bonding the peripheral side surfaces of the plurality of honeycomb segments together. By using the honeycomb bonded body, it is possible to increase the total cross-sectional area of ​​the cells 13, which is important for ensuring the air flow rate, while suppressing the occurrence of cracks. The bonding layer can be formed using a bonding material. The bonding material is not particularly limited, but a ceramic material with a solvent such as water added thereto to form a paste can be used. The bonding material may contain a material having PTC properties, or may contain the same material as the outer peripheral wall 11 and the partition walls 14. In addition to bonding the honeycomb segments together, the bonding material can also be used as an outer peripheral coating material after bonding the honeycomb segments.

[0036] From the standpoints of ensuring the strength of the honeycomb structure 15, reducing pressure loss when air passes through the cells 13, ensuring the amount of functional material carried, and ensuring the contact area with the air flowing within the cells 13, it is desirable to appropriately combine the thickness of the partition walls 14, the cell density, and the cell pitch (or the opening rate of the cells 13). In this specification, cell density is a value obtained by dividing the number of cells by the area of ​​one end face (first end face 12a or second end face 12b) of the honeycomb structure 15 (the total area of ​​the partition walls 14 and cells 13 excluding the outer wall 11). In this specification, the cell pitch refers to a value calculated by the following calculation. First, the area per cell is calculated by dividing the area of ​​one end face (first end face 12a or second end face 12b) of the honeycomb structure 15 (the total area of ​​the partition walls 14 and the cells 13 excluding the outer peripheral wall 11) by the number of cells. Next, the square root of the area per cell is calculated, and this is defined as the cell pitch. In this specification, the opening ratio of the cells 13 is a value obtained by dividing the total area of ​​the cells 13 partitioned by the partition walls 14 in a cross section perpendicular to the flow direction of the honeycomb structure 15 by the area of ​​one end face (the first end face 12a or the second end face 12b) of the honeycomb structure 15 (the total area of ​​the partition walls 14 and the cells 13 excluding the outer peripheral wall 11). Note that when calculating the opening ratio of the cells 13, the pair of electrodes 16a, 16b and the dehumidifying layer 17 are not taken into consideration.

[0037] In an embodiment advantageous from the viewpoint of carrying a sufficient amount of functional material, the thickness of the partition wall 14 is 0.300 mm or less, and the cell density is 100 cells / cm 2 In a preferred embodiment, the thickness of the partition wall 14 is 0.200 mm or less, and the cell density is 70 cells / cm. 2 In a more preferred embodiment, the thickness of the partition walls 14 is 0.130 mm or less, and the cell density is 65 cells / cm. 2 and the cell pitch is 1.3 mm or more.

[0038] From the viewpoint of ensuring the strength of the honeycomb structure 15 and keeping the electrical resistance low, the lower limit of the thickness of the partition walls 14 is preferably 0.010 mm or more, more preferably 0.020 mm or more, and even more preferably 0.030 mm or more. From the viewpoints of ensuring the strength of the honeycomb structure 15, keeping the electrical resistance low, and increasing the surface area to promote reaction, adsorption, and desorption, the lower limit of the cell density is 30 cells / cm. 2 Preferably, 35 cells / cm or more. 2 More preferably, 40 cells / cm or more. 2 It is even more preferable that the above is true. From the viewpoints of ensuring the strength of the honeycomb structure 15, maintaining low electrical resistance, and increasing the surface area to promote reaction, adsorption, and desorption, the upper limit of the cell pitch is preferably 2.0 mm or less, more preferably 1.8 mm or less, and even more preferably 1.6 mm or less.

[0039] In an embodiment that is advantageous from the viewpoint of achieving both a reduction in pressure loss and a maintenance of strength, the partition walls 14 have a thickness of 0.08 to 0.36 mm and a cell density of 2.54 to 140 cells / cm. 2 In a preferred embodiment, the partition walls 14 have a thickness of 0.09 to 0.35 mm and a cell density of 15 to 100 cells / cm. 2 In a more preferred embodiment, the thickness of the partition walls 14 is 0.14 to 0.30 mm, and the cell density is 20 to 90 cells / cm. 2 The aperture ratio of the cell 13 is 0.85 or more.

[0040] From the viewpoint of ensuring the strength of the honeycomb structure 15, the upper limit of the opening ratio of the cells 13 is preferably 0.94 or less, more preferably 0.92 or less, and even more preferably 0.90 or less.

[0041] The thickness of the peripheral wall 11 is not particularly limited, but is preferably determined based on the following viewpoints. First, from the viewpoint of reinforcing the honeycomb structure 15, the thickness of the peripheral wall 11 is preferably 0.05 mm or more, more preferably 0.06 mm or more, and even more preferably 0.08 mm or more. On the other hand, from the viewpoint of increasing the electrical resistance to suppress the initial current, and from the viewpoint of reducing the pressure loss during air circulation, the thickness of the peripheral wall 11 is preferably 1.0 mm or less, more preferably 0.5 mm or less, even more preferably 0.4 mm or less, and even more preferably 0.3 mm or less. In this specification, the thickness of the outer peripheral wall 11 refers to the length in the normal direction of the side surface from the boundary between the outer peripheral wall 11 and the outermost cell 13 or partition wall 14 to the side surface of the honeycomb structure 15 in a cross section perpendicular to the flow path direction.

[0042] The length of the honeycomb structure 15 in the flow path direction and the cross-sectional area perpendicular to the flow path direction are not particularly limited and may be adjusted according to the required size of the dehumidification device 10. For example, when used in a compact dehumidification device 10 while ensuring a predetermined function, the honeycomb structure 15 has a length in the flow path direction of 2 to 20 mm and a cross-sectional area perpendicular to the flow path direction of 10 cm. 2 The upper limit of the cross-sectional area perpendicular to the flow path direction is not particularly limited, but may be, for example, 300 cm 2 It is.

[0043] The partition walls 14 constituting the honeycomb structure 15 are made of a material capable of generating heat when electricity is applied thereto, specifically, made of a material having a PTC characteristic. If necessary, the outer peripheral wall 11 may also be made of a material having a PTC characteristic like the partition walls 14. With this configuration, it is possible to directly heat the dehumidifying layer 17 by heat transfer from the partition walls 14 (and the outer peripheral wall 11, if necessary) that generate heat. In addition, a material having a PTC characteristic has a characteristic that, when the temperature rises and exceeds the Curie point, the resistance value rises rapidly and it becomes difficult for electricity to flow. Therefore, when the partition walls 14 (and the outer peripheral wall 11, if necessary) become hot, the current flowing therethrough is limited, and excessive heat generation in the honeycomb structure 15 is suppressed. Therefore, it is also possible to suppress thermal deterioration of the dehumidifying layer 17 caused by excessive heat generation.

[0044] From the viewpoint of obtaining an appropriate heat generation, the lower limit of the volume resistivity of the material having the PTC characteristics at 25°C is preferably 0.5 Ω·cm or more, more preferably 1 Ω·cm or more, and even more preferably 5 Ω·cm or more. From the viewpoint of generating heat at a low driving voltage, the upper limit of the volume resistivity of the material having the PTC characteristics at 25°C is preferably 30 Ω·cm or less, more preferably 18 Ω·cm or less, and even more preferably 16 Ω·cm or less. In this specification, the volume resistivity of the material having the PTC characteristics at 25°C is measured in accordance with JIS K6271:2008.

[0045] From the viewpoint of being able to generate heat when electricity is applied and having PTC characteristics, the outer peripheral wall 11 and the partition walls 14 are preferably made of a material mainly composed of barium titanate (BaTiO3). This material is more preferably a ceramic made of a material mainly composed of barium titanate (BaTiO3)-based crystal particles in which part of Ba is replaced with a rare earth element. In this specification, the term "main component" means a component that accounts for more than 50 mass% of the total components. The content of BaTiO3-based crystal particles can be determined by fluorescent X-ray analysis. Other crystal particles can also be measured in the same manner.

[0046] The composition formula of BaTiO3-based crystal particles in which part of Ba is replaced by rare earth elements is (Ba 1-x A x )TiO3, where A represents one or more rare earth elements and 0.0001≦x≦0.010. A is not particularly limited as long as it is a rare earth element, but is preferably one or more selected from the group consisting of La, Ce, Pr, Nd, Eu, Gd, Dy, Ho, Er, Y and Yb, and more preferably La. x is preferably 0.001 or more, more preferably 0.0015 or more, from the viewpoint of suppressing the electrical resistance at room temperature from becoming too high. On the other hand, x is preferably 0.009 or less, from the viewpoint of suppressing the electrical resistance at room temperature from becoming too high due to insufficient sintering. The content of BaTiO3-based crystal particles in the ceramics, in which a part of Ba is replaced by a rare earth element, is not particularly limited as long as it is the amount that serves as the main component, but is preferably 90 mass% or more, more preferably 92 mass% or more, and even more preferably 94 mass% or more. The upper limit of the content of BaTiO3-based crystal particles is not particularly limited, but is generally 99 mass%, preferably 98 mass%. The content of the BaTiO3 crystal particles can be measured by fluorescent X-ray analysis. Other crystal particles can also be measured in the same manner.

[0047] From the viewpoint of reducing the environmental load, it is desirable that the material used for the outer peripheral wall 11 and the partition wall 14 does not substantially contain lead (Pb). Specifically, the Pb content of the outer peripheral wall 11 and the partition wall 14 is preferably 0.01 mass% or less, more preferably 0.001 mass% or less, and even more preferably 0 mass%. With a low Pb content, for example, air heated by contacting the partition wall 14 during heat generation can be safely applied to living organisms such as humans. Note that the Pb content of the outer peripheral wall 11 and the partition wall 14, when converted to PbO, is preferably less than 0.03 mass%, more preferably less than 0.01 mass%, and even more preferably 0 mass%. The lead content can be determined by ICP-MS (inductively coupled plasma mass spectrometry).

[0048] The Curie points of the materials constituting the outer peripheral wall 11 and the partition walls 14 are preferably in the temperature range in which the resistance value becomes at least twice the resistance value at room temperature (25° C.). If the Curie points are in such a temperature range, the current flowing through them is limited when the dehumidifying device 10 becomes hot, so that excessive heat generation in the dehumidifying device 10 is efficiently suppressed. Therefore, thermal deterioration of the dehumidifying layer 17 caused by excessive heat generation can be suppressed. The lower limit of the Curie point of the material constituting the outer peripheral wall 11 and the partition wall 14 is preferably 80° C. or higher, more preferably 100° C. or higher, even more preferably 110° C. or higher, and particularly preferably 125° C. or higher, from the viewpoint of efficiently heating the dehumidifying layer 17. Meanwhile, the upper limit of the Curie point is preferably 200° C. or lower, more preferably 190° C. or lower, even more preferably 180° C. or lower, and particularly preferably 150° C. or lower, from the viewpoint of safety as a part placed in the vehicle interior or in the vicinity of the vehicle interior.

[0049] The Curie point of the material constituting the outer peripheral wall 11 and the partition walls 14 can be adjusted by the type and amount of the shifter added. For example, the Curie point of barium titanate (BaTiO3) is about 120°C, but by substituting a part of Ba and Ti with one or more of Sr, Sn, and Zr, the Curie point can be shifted to the lower temperature side.

[0050] In this specification, the Curie point is measured by the following method. A sample is attached to a sample holder for measurement and placed in a measurement tank (e.g., MINI-SUBZERO MC-810P, manufactured by Espec Corporation), and the change in electrical resistance of the sample relative to the temperature change when the temperature is raised from 10°C is measured using a DC resistance meter (e.g., multimeter 3478A, manufactured by Yokogawa Hewlett Packard, Ltd.). The temperature at which the resistance value is twice the resistance value at room temperature (20°C) based on the electrical resistance-temperature plot obtained by the measurement is taken as the Curie point.

[0051] (1-2. Pair of electrodes 16a, 16b) As shown in FIG. 2A, a pair of electrodes 16a, 16b are provided on the first end surface 12a and the second end surface 12b. By applying a voltage between the pair of electrodes 16a and 16b, it becomes possible to cause the honeycomb structure 15 to generate heat by Joule heat.

[0052] The pair of electrodes 16a, 16b is not particularly limited, and may be, for example, a metal or alloy containing at least one selected from Cu, Ag, Al, Ni, and Si. An ohmic electrode capable of making ohmic contact with the outer peripheral wall 11 and / or the partition wall 14 having PTC characteristics may also be used. The ohmic electrode may be, for example, an ohmic electrode containing at least one selected from Al, Au, Ag, and In as a base metal and at least one selected from Ni, Si, Zn, Ge, Sn, Se, and Te for n-type semiconductors as a dopant. The pair of electrodes 16a, 16b may have a single-layer structure or a laminated structure of two or more layers. When the pair of electrodes 16a, 16b has a laminated structure of two or more layers, the materials of the layers may be the same or different.

[0053] The thickness of the pair of electrodes 16a, 16b can be appropriately set depending on the method for forming the pair of electrodes 16a, 16b. Examples of the method for forming the pair of electrodes 16a, 16b include metal deposition methods such as sputtering, vapor deposition, electrolytic deposition, and chemical deposition. The pair of electrodes 16a, 16b can also be formed by applying an electrode paste and then baking it, or by thermal spraying. Furthermore, the pair of electrodes 16a, 16b may be formed by joining metal or alloy plates.

[0054] The thickness of the pair of electrodes 16a, 16b is preferably about 5 to 30 μm for baking of electrode paste, about 100 to 1000 nm for dry plating such as sputtering and vapor deposition, about 10 to 100 μm for thermal spraying, and about 5 to 30 μm for wet plating such as electrolytic deposition and chemical deposition. In addition, in joining metal or alloy plates, the thickness is preferably about 5 to 100 μm.

[0055] (1-3. Terminal 18) The terminal 18 is connected to the pair of electrodes 16a, 16b and is provided on at least a part of the pair of electrodes 16a, 16b. The provision of the terminal 18 facilitates connection to an external power source. The terminal 18 is connected to a conductor that is connected to a power source 20.

[0056] The material of the terminal 18 is not particularly limited, and may be, for example, a metal. As the metal, a simple metal or an alloy may be adopted, but from the viewpoints of corrosion resistance, electrical resistivity, and linear expansion coefficient, an alloy containing at least one selected from the group consisting of Cr, Fe, Co, Ni, Cu, Al, and Ti is preferable, and stainless steel, Fe-Ni alloy, and phosphor bronze are more preferable.

[0057] The size and shape of the terminal 18 are not particularly limited. For example, as shown in Fig. 2A, the terminal 18 may be provided on the entire pair of electrodes 16a, 16b on the outer peripheral wall 11. The terminal 18 may be provided on a part of the pair of electrodes 16a, 16b on the outer peripheral wall 11, or may be provided so as to extend outward beyond the outer edge of the pair of electrodes 16a, 16b on the outer peripheral wall 11. Furthermore, the terminal 18 may be provided on a part of the pair of electrodes 16a, 16b on the partition wall 14, or may be provided so as to cover some of the cells 13. The thickness of the terminal 18 is not particularly limited, but is, for example, 0.01 to 10 mm, typically 0.05 to 5 mm.

[0058] The method of connecting the terminal 18 and the pair of electrodes 16a, 16b is not particularly limited as long as they are electrically connected, and they can be connected by, for example, diffusion bonding, a mechanical pressure mechanism, welding, or the like.

[0059] (1-4.Dehumidification layer 17) The dehumidifying layer 17 can be provided on the surface of the partition wall 14 (in the case of the outermost cell 13, the partition wall 14 and the outer peripheral wall 11 which define the outermost cell 13). By providing the dehumidifying layer 17 in this manner, the dehumidifying layer 17 can be easily heated during the regeneration process, so that the dehumidifying function of the dehumidifying layer 17 can be regenerated.

[0060] The dehumidifying layer 17 contains a dehumidifying material. The dehumidifying material is not particularly limited, but a moisture absorbing material can be used. The moisture absorbent preferably has a function of being able to adsorb moisture (water vapor) at −20 to 40° C. and release it at a high temperature of 60° C. or higher. Examples of moisture absorbents having such a function include aluminosilicate, silica gel, silica, graphene oxide, polymeric moisture absorbents, polystyrene sulfonic acid, and metal organic frameworks (MOFs). These may be used alone or in combination of two or more.

[0061] As the aluminosilicate, it is preferable to use a porous clay mineral such as AFI-type, CHA-type or BEA-type zeolite, allophane, imogolite, etc. In addition, it is preferable that the aluminosilicate is amorphous.

[0062] As the silica gel, it is preferable to use type A silica gel. The polymer moisture absorbent is preferably one having a polyacrylic acid polymer chain, for example, sodium polyacrylate. The metal organic framework is a crystalline hybrid material containing metal ions and organic molecules (organic ligands). The metal ions are preferably hydrophilic metal ions (e.g., aluminum ions).

[0063] The dehumidifying layer 17 may contain a functional material other than the dehumidifying material, or a catalyst. The functional material other than the dehumidifying material is not particularly limited as long as it can exert a desired function, and may be an adsorbent, a catalyst, or the like. The adsorbent preferably has a function of adsorbing at least one selected from carbon dioxide and volatile components. In addition, the components to be removed can be purified by using a catalyst. Furthermore, the adsorbent and the catalyst may be used in combination for the purpose of enhancing the function of the adsorbent to capture the components to be removed.

[0064] Adsorbents include zeolites, silica gel, activated carbon, alumina, silica, low crystallinity clays, amorphous aluminum silicate complexes, etc. Some of these components may also function as moisture absorbents. The adsorbents may be used alone or in combination of two or more.

[0065] The catalyst preferably has a function capable of promoting the oxidation-reduction reaction. Examples of catalysts having such a function include metal catalysts such as Pt, Pd, and Ag, and oxide catalysts such as CeO2 and ZrO2. The catalyst may be used alone or in combination of two or more kinds.

[0066] Volatile components contained in the air in the vehicle cabin include, for example, volatile organic compounds (VOCs) and odor components other than VOCs. Specific examples of volatile components include ammonia, acetic acid, isovaleric acid, nonenal, formaldehyde, toluene, xylene, paradichlorobenzene, ethylbenzene, styrene, chlorpyrifos, di-n-butyl phthalate, tetradecane, di-2-ethylhexyl phthalate, diazinon, acetaldehyde, and N-methylcarbamate-2-(1-methylpropyl)phenyl.

[0067] The thickness of the dehumidifying layer 17 is not particularly limited and may be determined depending on the size of the cells 13. For example, from the viewpoint of ensuring sufficient contact with air, the thickness of the dehumidifying layer 17 is preferably 20 μm or more, more preferably 25 μm or more, and even more preferably 30 μm or more. On the other hand, from the viewpoint of preventing the dehumidifying layer 17 from peeling off from the partition walls 14 and the outer peripheral wall 11, the thickness of the dehumidifying layer 17 is preferably 400 μm or less, more preferably 380 μm or less, and even more preferably 350 μm or less.

[0068] The thickness of the dehumidifying layer 17 is measured by the following procedure. An arbitrary cross section parallel to the flow path direction of the honeycomb structure 15 is cut out, and a cross-sectional image at about 50x is obtained using a scanning electron microscope or the like. This cross section is also set to pass through the center of gravity of the cross section perpendicular to the flow paths of the honeycomb structure 15. For each dehumidifying layer 17 visible from the cross-sectional image, the thickness is calculated by dividing the cross-sectional area by the length of the cell 13 in the flow path direction. This calculation is performed for all dehumidifying layers 17 visible from the cross-sectional image, and the overall average value is taken as the thickness of the dehumidifying layer 17.

[0069] From the viewpoint of the dehumidifying material or the like exerting the desired function in the dehumidifying device 10, the amount of the dehumidifying layer 17 is preferably 50 to 500 g / L, more preferably 100 to 400 g / L, and further preferably 150 to 350 g / L, relative to the volume of the honeycomb structure 15. The volume of the honeycomb structure 15 is a value determined by the outer dimensions of the honeycomb structure 15.

[0070] (1-5. Method for manufacturing the dehumidifying device 10) The method for producing the dehumidifying device 10 is not particularly limited and can be performed according to a known method. The method for producing the dehumidifying device 10 will be described below as an example. The method for manufacturing the honeycomb structure 15 constituting the dehumidifying device 10 includes a molding step and a firing step. In the forming step, a clay containing ceramic raw materials including BaCO3 powder, TiO2 powder, and powder of a rare earth nitrate or hydroxide is formed to produce a honeycomb formed body having a relative density of 60% or more. The ceramic raw material can be obtained by dry mixing each powder so as to obtain a desired composition. The clay can be obtained by adding a dispersion medium, a binder, a plasticizer, and a dispersant to a ceramic raw material and kneading the mixture. The clay may contain additives such as a sifter, a metal oxide, a property improver, and a conductive powder, as necessary. The blending amount of components other than the ceramic raw materials is not particularly limited as long as the blending amount is such that the relative density of the honeycomb formed body is 60% or more.

[0071] In this specification, the "relative density of the honeycomb formed body" means the ratio of the density of the honeycomb formed body to the true density of the entire ceramic raw material. Specifically, it can be calculated by the following formula. Relative density of honeycomb formed body (%) = Density of honeycomb formed body (g / cm 3 ) / True density of ceramic raw material (g / cm 3 ) x 100 The density of the honeycomb molded body can be measured by the Archimedes method using pure water as a medium. The true density of the entire ceramic raw material is calculated by multiplying the total mass (g) of each raw material by the total actual volume (cm 3 ) can be calculated by dividing it by

[0072] The dispersion medium may be water or a mixed solvent of water and an organic solvent such as alcohol, with water being particularly preferred.

[0073] Examples of the binder include organic binders such as methyl cellulose, hydroxypropoxyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol. In particular, it is preferable to use methyl cellulose and hydroxypropoxyl cellulose in combination. The binder may be used alone or in combination of two or more kinds, but it is preferable that the binder does not contain an alkali metal element.

[0074] Examples of the plasticizer include polyoxyalkylene alkyl ethers, polycarboxylic acid polymers, and alkyl phosphate esters.

[0075] The dispersant may be a surfactant such as polyoxyalkylene alkyl ether, ethylene glycol, dextrin, fatty acid soap, polyalcohol, etc. The dispersant may be used alone or in combination of two or more kinds.

[0076] The honeycomb formed body can be produced by extruding a clay. In the extrusion molding, a die having a desired overall shape, cell shape, partition wall thickness, cell density, etc. can be used.

[0077] The relative density of the honeycomb molded body obtained by extrusion molding is 60% or more, preferably 65% ​​or more. By controlling the relative density of the honeycomb molded body within this range, it is possible to densify the honeycomb molded body and reduce the electrical resistance at room temperature. The upper limit of the relative density of the honeycomb molded body is not particularly limited, but is generally 80%, preferably 75%.

[0078] The honeycomb molded body can be dried before the firing step. The drying method is not particularly limited, and for example, a conventionally known drying method such as hot air drying, microwave drying, dielectric drying, reduced pressure drying, vacuum drying, freeze drying, etc. Among these, a drying method that combines hot air drying with microwave drying or dielectric drying is preferred because it can quickly and uniformly dry the entire molded body.

[0079] The firing step involves holding the material at 1150-1250° C., then increasing the temperature to a maximum temperature of 1360-1430° C. at a rate of 20-600° C. / hour, and holding the temperature for 0.5-10 hours. By holding the honeycomb formed body at a maximum temperature of 1360 to 1430° C. for 0.5 to 10 hours, it is possible to obtain a honeycomb structure 15 mainly composed of BaTiO3-based crystal grains in which part of Ba has been substituted with a rare earth element. Moreover, by maintaining the temperature at 1150 to 1250° C., Ba2TiO4 crystal particles generated during the firing process are easily removed, so that the honeycomb structure 15 can be densified. Furthermore, by setting the heating rate from 1150-1250°C to the maximum temperature of 1360-1430°C at 20-600°C / hour, 1.0-10.0 mass% of Ba6Ti 17 O 40 Crystal grains can be generated in the honeycomb structure 15 .

[0080] The holding time at 1150 to 1250° C. is not particularly limited, but is preferably 0.5 to 10 hours. By setting the holding time in this range, Ba2TiO4 crystal particles formed during the firing process can be stably and easily removed.

[0081] The firing step preferably includes holding the mixture at 900 to 950° C. for 0.5 to 5 hours during heating. Holding the mixture at 900 to 950° C. for 0.5 to 5 hours allows BaCO3 to efficiently decompose, making it easier to obtain a honeycomb structure 15 having a predetermined composition.

[0082] Before the firing step, a degreasing step may be carried out to remove the binder. The degreasing step is preferably carried out in an air atmosphere in order to completely decompose the organic components. Moreover, it is preferable that the firing step be performed in an air atmosphere from the viewpoints of controlling electrical characteristics and reducing manufacturing costs. The firing furnace used in the firing step and the degreasing step is not particularly limited, but an electric furnace, a gas furnace, or the like can be used.

[0083] A pair of electrodes 16a, 16b are formed on the honeycomb structure 15 thus obtained. The pair of electrodes 16a, 16b can be formed by a metal deposition method such as sputtering, vapor deposition, electrolytic deposition, or chemical deposition. The pair of electrodes 16a, 16b can also be formed by applying an electrode paste and then baking it. Furthermore, the pair of electrodes 16a, 16b can also be formed by thermal spraying. The pair of electrodes 16a, 16b may be formed of a single layer, but may also be formed of multiple electrode layers with different compositions. A representative method for forming the pair of electrodes 16a, 16b will be described below.

[0084] First, an electrode slurry containing an electrode material, an organic binder, and a dispersion medium is prepared and applied to the first end face 12a or the second end face 12b of the honeycomb structure 15. The dispersion medium can be water, an organic solvent (e.g., toluene, xylene, ethanol, n-butanol, ethyl acetate, butyl acetate, terpineol, dihydroterpineol, texanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether), or a mixture thereof. Excess slurry on the outer periphery of the honeycomb structure 15 is removed by blowing and wiping. Thereafter, the slurry is dried to form a pair of electrodes 16a, 16b on the first end face 12a or the second end face 12b of the honeycomb structure 15. Drying can be performed while heating a heater element to a temperature of, for example, about 120 to 600°C. The series of steps of coating, slurry removal, and drying may be carried out only once, but by repeating the steps multiple times, a pair of electrodes 16a, 16b having a desired thickness can be provided.

[0085] Next, when providing the terminal 18, the terminal 18 is placed at a predetermined position of the pair of electrodes 16a, 16b, and the pair of electrodes 16a, 16b is connected to the terminal 18. The method for connecting the pair of electrodes 16a, 16b to the terminal 18 can be the above-mentioned method. The terminal 18 may be installed after the dehumidifying layer 17 described below is formed.

[0086] Next, the dehumidifying layer 17 is formed on the surfaces of the partition walls 14 and the like of the honeycomb structure 15 . The method for forming the dehumidifying layer 17 is not particularly limited, but for example, the dehumidifying layer 17 can be formed by the following process. The honeycomb structure 15 is immersed in a slurry containing a dehumidifying material, an organic binder, and a dispersion medium for a predetermined time, and excess slurry on the end face and outer periphery of the honeycomb structure 15 is removed by blowing and wiping. The dispersion medium can be water, an organic solvent (e.g., toluene, xylene, ethanol, n-butanol, ethyl acetate, butyl acetate, terpineol, dihydroterpineol, texanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether), or a mixture thereof. Thereafter, the slurry is dried to form the dehumidifying layer 17 on the surface of the partition wall 14. The drying can be performed while heating the honeycomb structure 15 to a temperature of, for example, about 120 to 600°C. The series of steps of immersion, slurry removal, and drying may be carried out only once, but by repeating the steps a number of times, a dehumidifying layer 17 of a desired thickness can be provided on the surface of the partition wall 14 or the like.

[0087] (2.Power supply 20) The power source 20 is for applying a voltage to the pair of electrodes 16a, 16b. The power source 20 is electrically connected to the control unit 90, and adjusts the state of the voltage applied to the pair of electrodes 16a, 16b according to instructions from the control unit 90. The power source 20 is not particularly limited, and a battery or the like can be used.

[0088] (3. Inlet piping 30) The inlet pipe 30 is a pipe for allowing air from the vehicle interior or outside the vehicle to flow into the dehumidifying device 10. The shape and size of the inlet pipe 30 may be appropriately adjusted depending on the type of vehicle, and are not particularly limited.

[0089] (4. First Outlet Pipe 40 and Second Outlet Pipe 50) Both the first outlet pipe 40 and the second outlet pipe 50 are pipes through which air that has passed through the dehumidifying device 10 flows. In particular, the first outlet pipe 40 is a pipe that returns the air dehumidified by the dehumidifying device 10 to the vehicle compartment, and the second outlet pipe 50 is a pipe through which air containing moisture released by the regeneration process of the dehumidifying device 10 flows. The shapes and sizes of the first outlet pipe 40 and the second outlet pipe 50 are not particularly limited and may be appropriately adjusted depending on the type of vehicle, etc. In addition, the first outlet pipe 40 and the second outlet pipe 50 may be separate pipes from the inlet pipe 30, or may be pipes integral with the inlet pipe 30.

[0090] The second outlet pipe 50 merges with the first outlet pipe 40 downstream of the separator 70. With this configuration, the heated air from which moisture has been removed by the separator 70 can be returned to the first outlet pipe 40, and can be effectively used for heating or the like.

[0091] As shown in Fig. 3, the first outflow pipe 40 and the second outflow pipe 50 may have a double pipe structure in which the second outflow pipe 50 is disposed inside the first outflow pipe 40 at the branching portion between the first outflow pipe 40 and the second outflow pipe 50. With such a configuration, the structure around the branching portion between the first outflow pipe 40 and the second outflow pipe 50 can be made compact, and a commercially available differential pressure valve 65 described below can be used at the branching portion. Fig. 3 is a schematic diagram of a vehicle air conditioning system according to another embodiment of the present invention.

[0092] (5. Switching valve 60) The switching valve 60 is provided at the branch point of the first outlet pipe 40 and the second outlet pipe 50, and has a function of switching the flow of air to the first outlet pipe 40 or the second outlet pipe 50. The switching of the switching valve 60 can be achieved, for example, by electrically connecting the control unit 90 and the switching valve 60 via an electric wire or wirelessly and operating the switch of the switching valve 60 using the control unit 90.

[0093] The switching valve 60 is not particularly limited as long as it is a valve that is electrically driven and has the function of switching the flow path, and examples of the switching valve 60 include a solenoid valve and an electric valve. For example, the switching valve 60 can include an actuator such as an opening / closing door supported on a rotating shaft and a motor that rotates the rotating shaft. The actuator is configured to be controllable by the control unit 90.

[0094] 3, the switching valve 60 is preferably a differential pressure valve 65 capable of switching the air flow to the first outlet pipe 40 or the second outlet pipe 50. By using the differential pressure valve 65, it is not necessary to provide a drive unit (e.g., an actuator) around the switching valve 60, so that the structure around the branching part can be made compact. The differential pressure valve 65 can be placed at the branch point of the first outlet pipe 40 and the second outlet pipe 50, and is not particularly limited as long as it is capable of opening and closing the flow path of the first outlet pipe 40 or the second outlet pipe 50 depending on the pressure in the pipe.

[0095] 4A and 4B, the differential pressure valve 65 includes a base 66, opening / closing portions 67a and 67b, and spring portions 68a and 68b that connect the base 66 to the opening / closing portions 67a and 67b. The differential pressure valve 65 having such a structure can control the pressure at which the opening / closing portions 67a and 67b open by adjusting the strength of the spring portions 68a and 68b. The differential pressure valve 65 can be controlled by a first ventilator 85a and a second ventilator 85b, which will be described below.

[0096] (6.Separator 70) The separator 70 has a function of separating moisture contained in the air by centrifugal separation. That is, the separator 70 is a gas-liquid separator that utilizes centrifugal force. The separator 70 applies a swirling flow to air containing moisture (water vapor), and separates the moisture to the outside and the air to the inside by centrifugal separation. Therefore, by disposing the separator 70 in the second outlet pipe 50, it is possible to selectively remove moisture from the air containing moisture released by the regeneration process of the dehumidification device 10.

[0097] The separator 70 is not particularly limited as long as it has a structure that applies centrifugal force to the flowing air. For example, the separator 70 may be a swirl vane disposed in the second outlet pipe 50. When a swirling vane is used as the separator 70, the moisture (condensed water) separated by centrifugal separation adheres to the inner wall of the second outlet pipe 50, so it is preferable that a branch discharge pipe 55 be provided in the second outlet pipe 50 for discharging the moisture separated by the separator 70 outside the vehicle.

[0098] From the standpoint of efficiently discharging the moisture separated by centrifugation outside the vehicle, it is preferable that the second outflow pipe 50 has a horizontal section 51 and an inclined section 52 inclined vertically upward toward the downstream side, with a separator 70 disposed in the inclined section 52 and a branch discharge pipe 55 provided at the boundary between the horizontal section 51 and the inclined section 52.

[0099] As the separator 70, a commercially available separator 70 having a function of separating moisture contained in air by centrifugation may be used. Specifically, as the separator 70, a cyclone type water separator may be used. A cyclone type water separator generally includes a housing, a cyclone cartridge, and a drain section (moisture discharge section), and centrifugally separates air that has flowed into the housing by the cyclone cartridge. Moisture separated by centrifugation can be discharged from the drain section. Therefore, when a commercially available separator 70 is used, it is not necessary to provide the inclined section 52 or the branch discharge pipe 55 in the second outlet pipe 50.

[0100] (7. Ventilator 80) The ventilator 80 is provided to circulate air through the pipes (the inlet pipe 30, the first outlet pipe 40, and the second outlet pipe 50). The ventilator 80 is not particularly limited, and a known ventilator can be used. The position of the ventilator 80 is not particularly limited, and may be provided in the inlet pipe 30 as shown in FIG. 1, but may also be provided in the outlet pipe (for example, at a position downstream of the junction of the first outlet pipe 40 and the second outlet pipe 50, or in both the first outlet pipe 40 and the second outlet pipe 50, etc.).

[0101] When the differential pressure valve 65 is used as the switching valve 60, as shown in Fig. 3, a first ventilator 85a is provided for controlling the differential pressure valve 65 to switch the air flow to the first outlet pipe 40, and a second ventilator 85b is provided for controlling the differential pressure valve 65 to switch the air flow to the second outlet pipe 50. Specifically, the first ventilator 85a is provided for controlling the opening / closing unit 67a of the differential pressure valve 65 to an open state, and the second ventilator 85b is provided for controlling the opening / closing unit 67b of the differential pressure valve 65 to an open state. The first ventilator 85a and the second ventilator 85b are not particularly limited, and known ventilators can be used.

[0102] FIG. 4A is a partially enlarged view showing the state of the differential pressure valve 65 in the dehumidification mode, and FIG. 4B is a partially enlarged view showing the state of the differential pressure valve 65 in the regeneration mode. In the dehumidification mode, the second fan 85b is stopped and the first fan 85a is started, thereby controlling the differential pressure valve 65 to switch the air flow to the first outlet pipe 40 as shown in Fig. 4A. In the regeneration mode, the first fan 85a is stopped and the second fan 85b is started, thereby controlling the differential pressure valve 65 to switch the air flow to the second outlet pipe 50 as shown in Fig. 4B.

[0103] The position of the first fan 85a is not particularly limited as long as it is a position where the differential pressure valve 65 can be controlled as described above. For example, the first fan 85a can be disposed in the inlet pipe 30. When the first fan 85a is disposed in such a position, starting the first fan 85a creates a positive pressure in the pipe upstream of the differential pressure valve 65. This positive pressure opens only the opening / closing part 67a of the differential pressure valve 65, and air flows into the first outlet pipe 40. In order to open only the opening / closing portion 67a of the differential pressure valve 65 by positive pressure, the spring portion 68a may be set to have a strength that allows it to open due to the positive pressure, and the spring portion 68b may be set to have a strength that does not allow it to open due to the positive pressure.

[0104] Furthermore, the first fan 85a may be provided in the first outlet pipe 40 downstream of the differential pressure valve 65 (at a position upstream of the junction with the second outlet pipe 50). When the first fan 85a is provided in such a position, when the first fan 85a is started, a negative pressure is created in the first outlet pipe 40 between the differential pressure valve 65 and the first fan 85a. This negative pressure opens only the opening / closing part 67a of the differential pressure valve 65, and air flows into the first outlet pipe 40. In this case, the strength of the spring part 68a and the spring part 68b of the differential pressure valve 65 may be approximately the same.

[0105] The position of the second fan 85b is not particularly limited as long as it is a position where the differential pressure valve 65 can be controlled as described above. For example, the second fan 85b can be disposed in the second outlet pipe 50 (at a position upstream of the junction with the first outlet pipe 40). When the second fan 85b is disposed in such a position, when the second fan 85b is started, a negative pressure is created in the second outlet pipe 50 between the differential pressure valve 65 and the second fan 85b. This negative pressure opens only the opening / closing part 67b of the differential pressure valve 65, and air flows into the second outlet pipe 50.

[0106] (8. Control unit 90) The control unit 90 can be provided to control the power source 20, the switching valve 60, the ventilator 80 (the first ventilator 85a and the second ventilator 85b), etc. The control unit 90 is electrically connected to the power source 20, the switching valve 60, the ventilator 80 (the first ventilator 85a and the second ventilator 85b), etc. The control unit 90 can adjust the heating state of the honeycomb structure 15 by controlling the power source 20 for applying a voltage to the pair of electrodes 16a, 16b of the dehumidifying device . The control unit 90 can switch the flow of air to the first outlet pipe 40 or the second outlet pipe 50 by controlling the switching valve 60 . The control unit 90 can start the ventilator 80 to circulate air through the piping. When the differential pressure valve 65 is used as the switching valve 60, the control unit 90 can control the first ventilator 85a to be started and the air flow in the differential pressure valve 65 to be switched to the first outlet pipe 40. The control unit 90 can also control the second ventilator 85b to be started and the air flow in the differential pressure valve 65 to be switched to the second outlet pipe 50.

[0107] The control unit 90 is not particularly limited, but is generally an ECU (Engine (electronic) Control Unit). The ECU includes a CPU that executes various arithmetic processes, a ROM that stores programs and data required for the control, a RAM that temporarily stores the results of the CPU calculations, and an input / output port for inputting and outputting signals to and from the outside.

[0108] It is preferable that the control unit 90 can execute a dehumidification mode in which the switching valve 60 is controlled to switch the air flow to the first outflow pipe 40 to dehumidify the interior of the vehicle, and a regeneration mode in which a voltage is applied to the pair of electrodes 16a, 16b of the dehumidifying device 10 and the switching valve 60 is controlled to switch the air flow to the second outflow pipe 50 to perform a regeneration process of the dehumidifying layer 17. In particular, when the switching valve 60 is a differential pressure valve 65, it is preferable that the control unit 90 can execute a dehumidification mode in which the first fan 85a is started and the differential pressure valve 65 is controlled to switch the air flow to the first outflow pipe 40 to dehumidify the interior of the vehicle, and a regeneration mode in which the second fan 85b is started and a voltage is applied to the pair of electrodes 16a, 16b of the dehumidifying device 10 and the differential pressure valve 65 is controlled to switch the air flow to the second outflow pipe 50 to perform a regeneration process of the dehumidifying layer 17. If such a mode is possible, in the dehumidification mode, moisture contained in the air from the passenger compartment can be removed and returned to the passenger compartment, and in the regeneration mode, the moisture captured in the dehumidification layer 17 can be discharged outside the vehicle by the separator 70 while heated air is returned to the passenger compartment.

[0109] It is preferable that the vehicle air conditioning system 100 further includes a detection unit (not shown) capable of detecting fogging of the glass in the vehicle cabin, and the control unit 90 executes the regeneration mode when fogging of the glass in the vehicle cabin is detected, and executes the dehumidification mode when fogging of the glass in the vehicle cabin is not detected. By controlling in this manner, it is possible to efficiently proceed with the regeneration process of the dehumidification layer 17 while suppressing fogging of the glass in the vehicle cabin.

[0110] The detection unit capable of detecting the fogging of the glass in the vehicle interior is not particularly limited, but it is preferable that the detection unit detects the fogging of the glass in the vehicle interior based on the temperature and humidity in the vehicle interior. A detection unit having such a function can stably detect the fogging of the glass.

[0111] In the regeneration mode of the dehumidifying layer 17, in order to promote the desorption of the moisture captured in the dehumidifying layer 17, it is preferable to heat the dehumidifying layer 17 to a temperature equal to or higher than the desorption temperature depending on the type of dehumidifying material. For example, the dehumidifying layer 17 is preferably heated to 70 to 150°C, more preferably to 80 to 140°C, and further preferably to 90 to 130°C.

[0112] From the viewpoint of stably performing the above control, it is desirable to place the dehumidifying device 10 in a position close to the vehicle interior. Therefore, from the viewpoint of preventing electric shock, etc., it is preferable that the driving voltage of the dehumidifying device 10 is 60 V or less. Since the honeycomb structure 15 used in the dehumidifying device 10 has low electrical resistance at room temperature, the honeycomb structure 15 can be heated at this low driving voltage. The lower limit of the driving voltage is not particularly limited, but is preferably 10 V or more. If the driving voltage is less than 10 V, the current when the honeycomb structure 15 is heated will be large, and therefore it is necessary to use thicker conductors. [Explanation of symbols]

[0113] 10. Dehumidifying Devices 11 Peripheral wall 12a 1st end surface 12b 2nd end face 13 Cell 14 Bulkhead 15 Honeycomb structure 16a, 16b Pair of electrodes 17 Dehumidification layer 18 Terminals 20 Power supply 30 Inlet piping 40 First Outlet Pipe 50 Second Outlet Pipe 51 Horizontal part 52 Slope 55 Branch discharge piping 60 Switching valve 65 Differential Pressure Valve 66 base 67a,67b Opening / closing part 68a, 68b Spring part 70 Separator 80 Ventilator 85a 1st ventilation fan 85b 2nd ventilation fan 90 Control section 100 Vehicle air conditioning system

Claims

1. a honeycomb structure having an outer peripheral wall and partition walls disposed inside the outer peripheral wall and defining a plurality of cells that serve as flow paths extending from a first end face to a second end face, the partition walls being made of a material having a PTC characteristic; a dehumidifying device including: a pair of electrodes provided on the first end face and the second end face; and a dehumidifying layer formed on a surface of the partition walls; A power source for applying a voltage to the pair of electrodes; an inlet pipe for introducing air from a vehicle interior or from outside the vehicle into the dehumidifying device; a first outlet pipe for returning the air dehumidified by the dehumidifying device to the vehicle compartment; a second outlet pipe through which the air containing moisture released by the regeneration process of the dehumidifying device flows; a switching valve provided at a branching portion between the first outlet pipe and the second outlet pipe and capable of switching the flow of the air to the first outlet pipe or the second outlet pipe; Equipped with a separator capable of separating moisture contained in the air by centrifugal separation is disposed in the second outflow pipe; The second outlet pipe joins the first outlet pipe downstream of the separator.

2. 2. The vehicle air conditioning system according to claim 1, further comprising a branch discharge pipe provided on the second outlet pipe for discharging the moisture separated by the separator.

3. The second outflow pipe has a horizontal portion and an inclined portion inclined vertically upward toward the downstream side, 3. The vehicle air conditioning system according to claim 2, wherein the separator is disposed in the inclined portion, and the branch discharge pipe is provided at a boundary between the horizontal portion and the inclined portion.

4. 2. The vehicle air conditioning system of claim 1, wherein the separator is a cyclone type water separator.

5. the switching valve is a differential pressure valve capable of switching the flow of the air to the first outlet pipe or the second outlet pipe, a first fan that controls the differential pressure valve to switch the flow of the air to the first outlet pipe; a second fan that controls the differential pressure valve to switch the flow of the air to the second outlet pipe; The vehicle air conditioning system according to any one of claims 1 to 4, further comprising:

6. The vehicle air conditioning system according to any one of claims 1 to 4, wherein at the branching portion between the first outlet pipe and the second outlet pipe, the second outlet pipe has a double pipe structure disposed inside the first outlet pipe.

7. The vehicle air conditioning system according to claim 5 , wherein the first fan is disposed in the inlet pipe.

8. 6. The vehicle air conditioning system according to claim 5, wherein the second fan is disposed in the second outlet pipe.

9. 5. The vehicle air conditioning system according to claim 1, wherein the material having PTC properties is mainly composed of barium titanate.

10. 5. The vehicle air conditioning system according to claim 1, wherein the dehumidifying layer contains an adsorbent having a function of adsorbing at least one selected from carbon dioxide and a volatile component, and / or a catalyst.

11. a dehumidification mode in which the switching valve is controlled to switch the flow of the air to the first outflow pipe to dehumidify the interior of the vehicle cabin; a regeneration mode in which a voltage is applied to the pair of electrodes of the dehumidifying device and the switching valve is controlled to switch the flow of the air to the second outlet pipe to perform a regeneration process of the dehumidifying layer; The vehicle air conditioning system according to any one of claims 1 to 4, further comprising a control unit capable of executing the above.

12. 12. The vehicle air conditioning system according to claim 11, further comprising a detection unit capable of detecting fogging of a glass in the vehicle compartment, wherein the control unit executes the regeneration mode when fogging of the glass is detected, and executes the dehumidification mode when fogging of the glass is not detected.

13. The vehicle air conditioning system according to claim 12, wherein the detector detects fogging of the glass based on temperature and humidity in the vehicle interior.

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