Vehicle air-conditioning system

Abstract

To provide a vehicle air-conditioning system capable of performing heating and dehumidification at the same time, using a heat pump cycle.SOLUTION: A vehicle air-conditioning system includes: an air-conditioning duct 10 allowing air from a cabin or a vehicle exterior to flow therethrough, and including two or more branch paths 11; an air-conditioning device 20 disposed at each of the two or more branch paths 11; a heat pump cycle 30 in which a condenser 31 for performing heat exchange between a refrigerant and the air, and an evaporator 32 for performing heat exchange between the refrigerant and the air are disposed; and a control section 40 for controlling the air-conditioning device 20 and the heat pump cycle 30 according to an operation mode. The air-conditioning device 20 includes: a honeycomb structure which includes an outer peripheral wall and partition walls disposed inside the outer peripheral wall to define a plurality of cells each forming a flow path extending from a first end face to a second end face, and in which at least the partition walls are composed of a material having PTC characteristics; and a dehumidifying layer formed on a surface of each partition wall.SELECTED DRAWING: Figure 1A

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] 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.

[0005] On the other hand, from the viewpoint of improving the heating efficiency of a vehicle, an air conditioning system using a heat pump cycle has been proposed (for example, Patent Document 4). However, it is difficult for an air conditioning system using a heat pump cycle to perform heating and dehumidification at the same time. Therefore, for example, when the inside of a vehicle is cold and heating operation is performed, moisture (water vapor) inside the vehicle is cooled by the cold glass and condenses, which causes the glass to fog up and tends to interfere with driving. Therefore, it is necessary to perform a dehumidification operation to remove humidity, but the inside of the vehicle becomes cold when the dehumidification operation is performed, and the heating effect is lost. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2020-104774 A [Patent Document 2] JP 2020-111282 A [Patent Document 3] International Publication No. 2020 / 036067 [Patent Document 4] DE 102006026359 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made to solve the above-mentioned problems, and has an object to provide a vehicle air conditioning system that uses a heat pump cycle and is capable of simultaneously performing heating and dehumidification. [Means for solving the problem]

[0008] As a result of intensive research into a vehicle air conditioning system using a heat pump cycle, the inventors have found that the above-mentioned problems can be solved by arranging a predetermined air conditioning device in an air conditioning duct having two or more branch paths, providing an inflow path for introducing air into the vehicle compartment and an outflow path for discharging air to the outside of the vehicle on the branch paths downstream of the air conditioning device, and arranging a condenser and an evaporator of the heat pump cycle in the air conditioning duct connected to the vehicle compartment, and have thus completed the present invention. That is, the present invention is exemplified as follows.

[0009] [1] An air conditioning duct that allows air from the vehicle cabin or outside the vehicle to flow and has two or more branch paths; an air conditioning device disposed in each of the two or more branch paths; a heat pump cycle in which a condenser for exchanging heat between a hot heat of a refrigerant and the air and an evaporator for exchanging heat between a cold heat of the refrigerant and the air are disposed in an air conditioning duct connected to the vehicle compartment downstream of the air conditioning device; a control unit that controls the air conditioning device and the heat pump cycle according to an operation mode; Equipped with the air-conditioning device includes 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, and a dehumidifying layer formed on a surface of the partition walls, The two or more branch paths have an inlet path downstream of the air conditioning device that allows the air to flow into the vehicle cabin, and an outlet path downstream of the air conditioning device that allows the air to flow outside the vehicle, and a switching valve that can switch the flow of the air is provided between the inlet path and the outlet path.

[0010] [2] The operating mode of the air conditioning device is: a dehumidification mode in which the air is dehumidified by controlling the switching valve in all of the branch paths so as to cause the air to flow into the inflow path and circulating the air through the air conditioning device; a dehumidification / regeneration mode in which, in some of the branch paths, the switching valve is controlled to cause the air to flow into the inflow path, thereby circulating the air through the air-conditioning device, thereby performing dehumidification, and, in the remaining branch paths, the switching valve is controlled to cause the air to flow out to the outflow path, thereby heating the air-conditioning device while circulating the air, thereby regenerating the dehumidification layer; The vehicle air conditioning system according to [1],

[0011] [3] The heat pump cycle comprises: a compressor that compresses and discharges the refrigerant; an outdoor heat exchanger for exchanging heat between the refrigerant and outdoor air; a heat exchanger in the outflow path for exchanging heat between the refrigerant and the heated air flowing through the outflow path; Further comprising: The operation mode of the heat pump cycle is The vehicle air conditioning system according to [1] or [2], further comprising a heating operation mode in which the refrigerant that has been heat exchanged in the exterior heat exchanger and the outflow path heat exchanger is compressed by the compressor, and the refrigerant discharged from the compressor is introduced into the condenser to heat the air.

[0012] [4] The vehicle air conditioning system according to any one of [1] to [3], wherein the material having the PTC property is mainly composed of barium titanate.

[0013] [5] The vehicle air conditioning system according to any one of [1] to [4], wherein the dehumidifying layer further contains an adsorbent having a function of adsorbing at least one selected from carbon dioxide and volatile components, and / or a catalyst.

[0014] [6] The vehicle air conditioning system according to any one of [2] to [5], further comprising a detection unit capable of detecting fogging of glass inside the vehicle cabin, wherein the control unit executes the dehumidification / regeneration mode when fogging of the glass is detected, and executes the dehumidification mode when fogging of the glass is not detected.

[0015] [7] The vehicle air conditioning system according to [6], wherein the detection unit detects fogging of the glass based on the temperature and humidity inside the vehicle cabin. Effect of the Invention

[0016] According to the present invention, it is possible to provide a vehicle air conditioning system that utilizes a heat pump cycle and is capable of simultaneously performing heating and dehumidification. [Brief description of the drawings]

[0017] [Figure 1A] 1 is a schematic configuration diagram of a vehicle air conditioning system according to an embodiment of the present invention, illustrating an operating state in a dehumidification / heating operation mode. [Figure 1B] FIG. 1 is a schematic diagram of a vehicle air conditioning system according to an embodiment of the present invention, illustrating an operating state in a dehumidification / regeneration / heating operation mode. [Figure 1C] FIG. 1 is a schematic diagram of a vehicle air conditioning system according to an embodiment of the present invention, illustrating an operating state in a dehumidification / regeneration / heating operation mode. [Figure 1D] FIG. 1 is a schematic diagram of a vehicle air conditioning system according to an embodiment of the present invention, illustrating an operating state in a dehumidification / regeneration / cooling operation mode. [Figure 1E] FIG. 1 is a schematic diagram of a vehicle air conditioning system according to an embodiment of the present invention, illustrating an operating state in a dehumidification / regeneration / cooling operation mode. [Figure 1F] 1 is a schematic diagram of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state in a regeneration / non-cooling / heating operation mode; [Figure 2A] 1 is a schematic diagram of a cross section parallel to a flow path direction of an air conditioning 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 air-conditioning device of FIG. 2A taken along line aa'. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The vehicle air conditioning system of the present invention comprises: an air conditioning duct having two or more branch paths through which air can flow from the vehicle compartment or outside the vehicle; air conditioning devices arranged in each of the two or more branch paths; a heat pump cycle in which a condenser for exchanging heat between the hot heat of the refrigerant and the air and an evaporator for exchanging heat between the cold heat of the refrigerant and the air are arranged in the air conditioning duct connected to the vehicle compartment downstream of the air conditioning device; and a control unit for controlling the air conditioning device and the heat pump cycle according to an operation mode; the air conditioning device includes a honeycomb structure having an outer peripheral wall and partition walls arranged inside the outer peripheral wall to define 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 PTC properties at least, and a dehumidifying layer formed on a surface of the partition walls; the two or more branch paths have an inflow path for introducing air into the vehicle compartment downstream of the air conditioning device and an outflow path for discharging air to the outside of the vehicle, and a switching valve for switching the flow of air is provided between the inflow path and the outflow path. The vehicle air conditioning system of the present invention, having such a configuration, can perform heating and dehumidification simultaneously, eliminating the need to alternate between heating and dehumidification, and improving energy efficiency in winter.

[0019] 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.

[0020] 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.

[0021] 1A to 1F are schematic diagrams of a vehicle air conditioning system according to an embodiment of the present invention, and are diagrams showing the operating state in each operation mode. In particular, FIG. 1A is a dehumidification / heating operation mode, FIGS. 1B and 1C are a dehumidification-regeneration / heating operation mode, FIGS. 1D and 1E are a dehumidification-regeneration / cooling operation mode, and FIG. 1F is a regeneration / non-cooling / heating operation mode. FIG. 2A is a schematic diagram of a cross section parallel to the flow path direction of an air conditioning device used in a vehicle air conditioning system according to an embodiment of the present invention. FIG. 2B is a schematic diagram of a cross section of line a-a' in the air conditioning device of FIG. 2A.

[0022] The vehicle air conditioning system according to the embodiment of the present invention includes an air conditioning duct 10, an air conditioning device 20, a heat pump cycle 30, and a control unit 40. The vehicle air conditioning system may further include a power source 50, a ventilator 60, and an air mix door 70. Each of these components will now be described in detail.

[0023] (1. Air conditioning duct 10) The air conditioning duct 10 allows air to flow from the vehicle cabin or outside the vehicle, and has two or more branch paths 11 (11a, 11b). The two or more branch paths 11 (11a, 11b) have an inflow path 12 (12a, 12b) that introduces air into the vehicle cabin downstream of the air conditioning device 20, and an outflow path 13 (13a, 13b) that discharges air to the outside of the vehicle, and a switching valve 14 (14a, 14b) that can switch the flow of air is provided between the inflow path 12 (12a, 12b) and the outflow path 13 (13a, 13b). It is preferable that the inflow paths 12 (12a, 12b) join together downstream to form one flow path.

[0024] The number of branch paths 11 of the air conditioning duct 10 is not particularly limited as long as it is two or more, but is preferably two to five, more preferably two to four, and further preferably two to three. The shape and size of the air conditioning duct 10 may be appropriately adjusted depending on the type of vehicle, and are not particularly limited.

[0025] The switching valve 14 (14a, 14b) can be provided at a branch point between the inflow path 12 (12a, 12b) and the outflow path 13 (13a, 13b). The switching of the switching valve 14 (14a, 14b) can be achieved, for example, by electrically connecting the control unit 40 and the switching valve 14 (14a, 14b) via an electric wire or wirelessly and operating the switch of the switching valve 14 (14a, 14b) using the control unit 40.

[0026] The switching valve 14 (14a, 14b) 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 such valves include solenoid valves and motor-operated valves. For example, the switching valve 14 (14a, 14b) 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 40.

[0027] (2. Air Conditioning Device 20) The air conditioning devices 20 (20a, 20b) are disposed in each of the two or more branch paths 11 (11a, 11b). The air conditioning devices 20 (20a, 20b) include a honeycomb structure 25 having an outer peripheral wall 21, partition walls 24 disposed inside the outer peripheral wall 21 and partitioning a plurality of cells 23 that become flow paths extending from a first end face 22a to a second end face 22b, at least the partition walls 24 being made of a material having PTC properties, and a dehumidifying layer 26 formed on the surface of the partition walls 24. The air conditioning device 20 may further include a pair of electrodes 27a, 27b for applying a voltage to the honeycomb structure 25, and a terminal 28 connected to the pair of electrodes 27a, 27b.

[0028] When air from the vehicle interior or outside flows into the air-conditioning device 20 through the air-conditioning duct 10, moisture in the air is captured (removed) by the dehumidifying layer 26 while passing through the air-conditioning device 20. Then, the air with reduced moisture can be allowed to flow into the vehicle interior through the inflow path 12. On the other hand, the performance of the dehumidification layer 26 gradually decreases as the amount of moisture captured increases, and therefore the dehumidification layer 26 must be regenerated. The regeneration process of the dehumidification layer 26 is performed by applying a voltage to the pair of electrodes 27a, 27b by the power source 50 controlled by the control unit 40, and heating the honeycomb structure 25. Since the dehumidification layer 26 is directly heated by heating the honeycomb structure 25, the moisture captured in the dehumidification layer 26 is efficiently desorbed or reacted from the dehumidification layer 26 and can be released to the outside of the vehicle via the outflow path 13.

[0029] (2-1. Honeycomb structure 25) The shape of the honeycomb structure 25 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 23 extend) of the honeycomb structure 25 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 22a and second end face 22b) have the same shape as the cross section. When the cross section and the end faces are polygonal, the corners may be chamfered.

[0030] The shape of the cells 23 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 25. These shapes may be used alone or in combination of two or more. Among these shapes, a square or hexagon is preferable. By providing the cells 23 of such a shape, the pressure loss during air flow can be reduced.

[0031] The honeycomb structure 25 may be a honeycomb bonded body having a plurality of honeycomb segments and a bonding layer bonding the outer peripheral side surfaces of the plurality of honeycomb segments. By using the honeycomb bonded body, it is possible to increase the total cross-sectional area of ​​the cells 23, 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 21 and the partition walls 24. 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.

[0032] From the standpoints of ensuring the strength of the honeycomb structure 25, reducing pressure loss when air passes through the cells 23, ensuring the amount of functional material carried, and ensuring the contact area with the air flowing within the cells 23, it is desirable to appropriately combine the thickness of the partition walls 24, the cell density, and the cell pitch (or the opening rate of the cells 23). 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 22a or second end face 22b) of the honeycomb structure 25 (the total area of ​​the partition walls 24 and cells 23 excluding the outer peripheral wall 21). 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 22a or second end face 22b) of the honeycomb structure 25 (the total area of ​​the partition walls 24 and the cells 23 excluding the outer peripheral wall 21) 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 23 is a value obtained by dividing the total area of ​​the cells 23 partitioned by the partition walls 24 in a cross section perpendicular to the flow direction of the honeycomb structure 25 by the area of ​​one end face (the first end face 22a or the second end face 22b) (the total area of ​​the partition walls 24 and the cells 23 excluding the outer peripheral wall 21). Note that when calculating the opening ratio of the cells 23, the pair of electrodes 27a, 27b and the dehumidification layer 26 are not taken into consideration.

[0033] In an embodiment advantageous from the viewpoint of carrying a sufficient amount of functional material, the thickness of the partition wall 24 is 0.300 mm or less, and the cell density is 100 cells / cm 2In a preferred embodiment, the thickness of the partition wall 24 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 wall 24 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.

[0034] From the viewpoint of ensuring the strength of the honeycomb structure 25 and keeping the electrical resistance low, the lower limit of the thickness of the partition walls 24 is preferably 0.010 mm or more, more preferably 0.020 mm or more, and further preferably 0.030 mm or more. From the viewpoints of ensuring the strength of the honeycomb structure 25, 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 More preferably, it is equal to or greater than this. From the viewpoints of ensuring the strength of the honeycomb structure 25, 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.

[0035] 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 24 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 thickness of the partition walls 24 is 0.09 to 0.35 mm, and the cell density is 15 to 100 cells / cm. 2 In a more preferred embodiment, the thickness of the partition walls 24 is 0.14 to 0.30 mm, and the cell density is 20 to 90 cells / cm. 2 The aperture ratio of the cell 23 is 0.85 or more.

[0036] From the viewpoint of ensuring the strength of the honeycomb structure 25, the upper limit of the opening ratio of the cells 23 is preferably 0.94 or less, more preferably 0.92 or less, and further preferably 0.90 or less.

[0037] The thickness of the peripheral wall 21 is not particularly limited, but is preferably determined based on the following viewpoints. First, from the viewpoint of reinforcing the honeycomb structure 25, the thickness of the peripheral wall 21 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 when air flows, the thickness of the peripheral wall 21 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 peripheral wall 21 refers to the length in the normal direction of the side surface of the honeycomb structure 25 from the boundary between the peripheral wall 21 and the most peripheral cell 23 or partition wall 24 to the side surface of the honeycomb structure 25 in a cross section perpendicular to the flow direction of the honeycomb structure 25.

[0038] The length of the honeycomb structure 25 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 air conditioning device 20. For example, when used in a compact air conditioning device 20 while ensuring a predetermined function, the honeycomb structure 25 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 The following is the result.

[0039] The partition walls 24 constituting the honeycomb structure 25 are made of a material capable of generating heat when electricity is applied, specifically, made of a material having a PTC (Positive Temperature Coefficient) property. If necessary, the outer peripheral wall 21 may also be made of a material having a PTC property like the partition walls 24. With this configuration, it is possible to directly heat the dehumidifying layer 26 by heat transfer from the partition walls 24 (and the outer peripheral wall 21, if necessary) that generate heat. In addition, a material having a PTC property has a property 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 24 (and the outer peripheral wall 21, if necessary) become hot, the current flowing therethrough is limited, and excessive heat generation in the honeycomb structure 25 is suppressed. Therefore, it is also possible to suppress thermal deterioration of the dehumidifying layer 26 caused by excessive heat generation.

[0040] 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.

[0041] From the viewpoint of being able to generate heat when electricity is applied and having PTC characteristics, the outer peripheral wall 21 and the partition walls 24 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.

[0042] 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.

[0043] From the viewpoint of reducing the environmental load, it is desirable that the material used for the outer peripheral wall 21 and the partition wall 24 does not substantially contain lead (Pb). Specifically, the Pb content of the outer peripheral wall 21 and the partition wall 24 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 24 during heat generation can be safely applied to living organisms such as humans. Note that the Pb content of the outer peripheral wall 21 and the partition wall 24, 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).

[0044] The Curie point of the material constituting the outer peripheral wall 21 and the partition walls 24 is preferably in the temperature range in which the resistance value becomes twice or more the resistance value at room temperature (25°C). If the Curie point is in such a temperature range, the current flowing through these materials is limited when the air-conditioning device 20 becomes hot, so that excessive heat generation in the air-conditioning device 20 is efficiently suppressed. Therefore, the thermal deterioration of the dehumidifying layer 26 caused by excessive heat generation can be suppressed. The lower limit of the Curie point of the material constituting the outer peripheral wall 21 and the partition wall 24 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 26. 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.

[0045] The Curie point of the material constituting the outer peripheral wall 21 and the partition walls 24 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.

[0046] 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.

[0047] (2-2. Pair of electrodes 27a, 27b) The pair of electrodes 27a, 27b may be provided on the first end face 22a and the second end face 22b as shown in Fig. 2A. The pair of electrodes 27a, 27b may also be provided on the outer peripheral wall 21 parallel to the direction in which the cells 23 extend. By applying a voltage between the pair of electrodes 27a and 27b, it becomes possible to cause the honeycomb structure 25 to generate heat by Joule heat.

[0048] The pair of electrodes 27a, 27b 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 21 and / or the partition wall 24 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 27a, 27b may have a single-layer structure or a laminated structure of two or more layers. When the pair of electrodes 27a, 27b has a laminated structure of two or more layers, the materials of the layers may be the same or different.

[0049] The thickness of the pair of electrodes 27a, 27b can be appropriately set depending on the method for forming the pair of electrodes 27a, 27b. Examples of the method for forming the pair of electrodes 27a, 27b include metal deposition methods such as sputtering, vapor deposition, electrolytic deposition, and chemical deposition. The pair of electrodes 27a, 27b can also be formed by applying an electrode paste and then baking it, or by thermal spraying. Furthermore, the pair of electrodes 27a, 27b may be formed by joining metal plates or alloy plates.

[0050] The thickness of the pair of electrodes 27a, 27b 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.

[0051] (2-3. Terminal 28) The terminal 28 is connected to the pair of electrodes 27a, 27b and is provided on at least a part of the pair of electrodes 27a, 27b. The provision of the terminal 28 makes it easy to connect to an external power source. The terminal 28 is connected to a conductor that is connected to a power source 50.

[0052] The material of the terminal 28 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 viewpoint 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.

[0053] The size and shape of the terminal 28 are not particularly limited. For example, as shown in Fig. 2A, the terminal 28 may be provided on the entire pair of electrodes 27a, 27b on the outer peripheral wall 21. The terminal 28 may be provided on a part of the pair of electrodes 27a, 27b on the outer peripheral wall 21, or may be provided so as to extend outward beyond the outer edge of the pair of electrodes 27a, 27b on the outer peripheral wall 21. Furthermore, the terminal 28 may be provided on a part of the pair of electrodes 27a, 27b on the partition wall 24, or may be provided so as to cover some of the cells 23. The thickness of the terminal 28 is not particularly limited, but is, for example, 0.01 to 10 mm, typically 0.05 to 5 mm.

[0054] The method of connecting the terminal 28 and the pair of electrodes 27a, 27b 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.

[0055] (2-4.Dehumidification layer 26) The dehumidifying layer 26 can be provided on the surface of the partition wall 24 (in the case of the outermost cell 23, the partition wall 24 and the outer peripheral wall 21 which define the outermost cell 23). By providing the dehumidifying layer 26 in this manner, the dehumidifying layer 26 can be easily heated during the regeneration process, so that the dehumidifying function of the dehumidifying layer 26 can be regenerated.

[0056] The dehumidifying layer 26 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.

[0057] 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.

[0058] 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).

[0059] The dehumidifying layer 26 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 an adsorbent or the like may be used. 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] The thickness of the dehumidifying layer 26 is not particularly limited and may be determined depending on the size of the cells 23. For example, from the viewpoint of ensuring sufficient contact with air, the thickness of the dehumidifying layer 26 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 26 from peeling off from the partition walls 24 and the outer peripheral wall 21, the thickness of the dehumidifying layer 26 is preferably 400 μm or less, more preferably 380 μm or less, and even more preferably 350 μm or less.

[0064] The thickness of the dehumidifying layer 26 is measured by the following procedure. An arbitrary cross section parallel to the flow path direction of the honeycomb structure 25 is cut out, and a cross-sectional image of about 50 times 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 25. For each dehumidifying layer 26 visible from the cross-sectional image, the thickness is calculated by dividing the cross-sectional area by the length of the cell 23 in the flow path direction. This calculation is performed for all dehumidifying layers 26 visible from the cross-sectional image, and the overall average value is taken as the thickness of the dehumidifying layer 26.

[0065] From the viewpoint of the dehumidifying material and the like exerting the desired function in the air-conditioning device 20, the amount of the dehumidifying layer 26 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 25. The volume of the honeycomb structure 25 is a value determined by the outer dimensions of the honeycomb structure 25.

[0066] (2-5. Method for manufacturing air conditioning device 20) The method for producing the air-conditioning device 20 is not particularly limited and may be performed according to a known method. The method for producing the air-conditioning device 20 will be described below as an example. The manufacturing method of the honeycomb structure 25 constituting the air-conditioning device 20 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.

[0067] 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

[0068] The dispersion medium may be water or a mixed solvent of water and an organic solvent such as alcohol, with water being particularly preferred.

[0069] 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.

[0070] Examples of the plasticizer include polyoxyalkylene alkyl ethers, polycarboxylic acid polymers, and alkyl phosphate esters.

[0071] 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.

[0072] 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.

[0073] 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%.

[0074] 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.

[0075] 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 25 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 25 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 25 .

[0076] 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.

[0077] 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 25 having a predetermined composition.

[0078] 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.

[0079] A pair of electrodes 27a, 27b are formed on the honeycomb structure 25 thus obtained. The pair of electrodes 27a, 27b can be formed by a metal deposition method such as sputtering, vapor deposition, electrolytic deposition, or chemical deposition. The pair of electrodes 27a, 27b can also be formed by applying an electrode paste and then baking it. Furthermore, the pair of electrodes 27a, 27b can also be formed by thermal spraying. The pair of electrodes 27a, 27b 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 27a, 27b will be described below.

[0080] First, an electrode slurry containing an electrode material, an organic binder, and a dispersion medium is prepared and applied to the first end surface 22a or the second end surface 22b of the honeycomb structure 25. 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 25 is removed by blowing and wiping. Thereafter, the slurry is dried to form a pair of electrodes 27a, 27b on the first end surface 22a or the second end surface 22b of the honeycomb structure 25. 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 27a, 27b of a desired thickness can be provided.

[0081] Next, when providing the terminal 28, the terminal 28 is placed at a predetermined position of the pair of electrodes 27a, 27b, and the pair of electrodes 27a, 27b is connected to the terminal 28. The method described above can be used to connect the pair of electrodes 27a, 27b to the terminal 28. The terminal 28 may be installed after the dehumidifying layer 26 described below is formed.

[0082] Next, the dehumidifying layer 26 is formed on the surfaces of the partition walls 24 and the like of the honeycomb structure 25 . The method for forming the dehumidifying layer 26 is not particularly limited, but for example, the dehumidifying layer 26 can be formed by the following process. The honeycomb structure 25 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 25 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 26 on the surface of the partition wall 24. The drying can be performed while heating the honeycomb structure 25 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 26 of a desired thickness can be provided on the surface of the partition wall 24 or the like.

[0083] (3. Heat Pump Cycle 30) The heat pump cycle 30 includes a condenser 31 and an evaporator 32 disposed in the air conditioning duct 10 connected to the vehicle compartment downstream of the air conditioning device 20 . Condenser 31 can exchange heat between the hot heat of the refrigerant and the air. Specifically, condenser 31 can dissipate heat by the high-temperature, high-pressure refrigerant flowing inside, and heats the air passing around condenser 31. The evaporator 32 can exchange heat between the cold of the refrigerant and the air. Specifically, the evaporator 32 can absorb heat by the low-temperature, low-pressure refrigerant flowing inside, and cools the air passing around the evaporator 32.

[0084] In addition to the condenser 31 and the evaporator 32, the heat pump cycle 30 may further include a compressor 33, an outdoor heat exchanger 34, an outflow path heat exchanger 35, expansion valves 36a, 36b, and shut-off valves 37a to 37f, and each of these components is connected via a refrigerant flow path.

[0085] Compressor 33 has a function of compressing and discharging the refrigerant. The compressor 33 has an intake section connected to the heat exchangers (exterior heat exchanger 34, outflow path heat exchanger 35) and a discharge section connected to the condenser 31 via a refrigerant flow path. Compressor 33 is driven by control unit 40, and compresses the refrigerant to discharge high-temperature, high-pressure refrigerant to condenser 31. In addition, a known device such as a gas-liquid separator may be provided between the compressor 33 and the heat exchanger.

[0086] The outdoor heat exchanger 34 has a function of exchanging heat between the heat of the refrigerant and the outside air. The outdoor heat exchanger 34 can absorb heat from the outside air by the low-temperature, low-pressure refrigerant circulating inside, mainly when the heating operation mode is performed, and vaporizes the refrigerant by absorbing heat from the outside air. Also, the outdoor heat exchanger 34 can dissipate heat to the outside air by the high-temperature, high-pressure refrigerant circulating inside, mainly when the cooling operation mode is performed, and cools the refrigerant by dissipating heat to the outside air.

[0087] The outflow path heat exchanger 35 has a function of exchanging heat between the refrigerant and the heated air flowing through the outflow path 13 (13a, 13b). The outflow path heat exchanger 35 can absorb heat from the heated air by the refrigerant flowing inside, mainly when the heating operation mode is being performed, and increases the temperature of the refrigerant by absorbing heat from the outside air. It should be noted that although FIGS. 1A to 1F show an example in which the in-outlet path heat exchanger 35 is provided only in the outflow path 13a, the in-outflow path heat exchanger 35 may also be provided in the outflow path 13b.

[0088] The expansion valves 36a and 36b are throttle valves whose opening can be adjusted by the control unit 40. In particular, when the heating operation mode is performed, the expansion valve 36a reduces the pressure of the refrigerant discharged from the condenser 31, expands it, and then discharges the low-temperature, low-pressure refrigerant to the exterior heat exchanger 34. In addition, when the cooling operation mode is performed, the expansion valve 36b reduces the pressure of the refrigerant from the exterior heat exchanger 34, expands it, and then discharges the low-temperature, low-pressure refrigerant to the evaporator 32.

[0089] The shutoff valves 37a to 37f are provided to control the flow path of the refrigerant. The opening and closing of the shutoff valves 37a to 37f is controlled by the control unit 40.

[0090] (4. Control unit 40) The control unit 40 controls the air conditioning device 20 and the heat pump cycle 30 according to the operation mode. Therefore, the control unit 40 is electrically connected to the air conditioning device 20 and the heat pump cycle 30. Specifically, the control unit 40 is connected to a power source 50 for applying a voltage to a pair of electrodes 27a, 27b of the air conditioning device 20, and the heating state of the honeycomb structure 25 can be adjusted by controlling the power source 50. In addition, the control unit 40 is electrically connected to the shutoff valves 37a to 37f of the heat pump cycle 30, and can control the flow path of the refrigerant by opening and closing the shutoff valves 37a to 37f. In addition, the control unit 40 is electrically connected to the expansion valves 36a, 36b of the heat pump cycle 30, and can control the degree of decompression of the refrigerant by adjusting the opening degree of the expansion valves 36a, 36b.

[0091] The control unit 40 is electrically connected to the switching valve 14, the ventilator 60, the air mix door 70, and the like in addition to the air conditioning device 20 and the heat pump cycle 30, and can control these.

[0092] The control unit 40 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.

[0093] (5.Power supply 50) The power supply 50 is for applying a voltage to the pair of electrodes 27a, 27b. The power supply 50 is electrically connected to the control unit 40, and adjusts the state of the voltage applied to the pair of electrodes 27a, 27b in accordance with instructions from the control unit 40. The power source 50 is not particularly limited, and a battery or the like can be used.

[0094] (6. Ventilator 60) The ventilator 60 is provided to circulate air through the air conditioning duct 10. There are no particular limitations on the type of ventilator 60, and any known ventilator can be used. The position of the ventilator 60 is not particularly limited, and may be provided, for example, on the upstream side of the air conditioning device 20. However, the ventilator 60 may also be provided on the downstream side of the condenser 31.

[0095] (7. Air Mix Door 70) The air mix door 70 is configured to rotate between a heating position in the air conditioning duct 10, where the heating path leading to the condenser 31 is opened, and a cooling position, where the cooling path bypassing the condenser 31 is opened. By rotating the air mix door 70 between the heating position and the cooling position, the ratio of air passing through the condenser 31 and air bypassing the condenser 31 can be adjusted, thereby adjusting the temperature of the air flowing into the vehicle cabin.

[0096] In the vehicle air conditioning system according to the embodiment of the present invention, the operation modes of the air conditioning device 20 (20a, 20b) may include a dehumidification mode, a regeneration mode, and a dehumidification / regeneration mode. In particular, the operation modes of the air conditioning device 20 (20a, 20b) preferably include a dehumidification mode and a dehumidification / regeneration mode. The operation mode of the air conditioning device 20 (20a, 20b) may be selected in response to a switch operation by the driver or a humidity change detected by various detection units.

[0097] (A) Dehumidification mode 1A, the dehumidification mode performs dehumidification by controlling the switching valves 14 (14a, 14b) in all of the branch paths 11 (11a, 11b) to cause the air to flow into the inflow paths 12 (12a, 12b) and circulating the air through the air conditioning devices 20 (20a, 20b). By executing such a dehumidification mode, the air from the vehicle interior or outside the vehicle can be quickly dehumidified.

[0098] (B) Playback mode 1F, in the regeneration mode, the switching valves 14 (14a, 14b) are controlled to cause air to flow out to the outflow paths 13 (13a, 13b) in all of the branch paths 11 (11a, 11b), thereby heating the air conditioning devices 20 (20a, 20b) and circulating air, thereby regenerating the dehumidification layer 26. By executing such a regeneration mode, the dehumidification layer 26 of the air conditioning devices 20 (20a, 20b) can be quickly regenerated.

[0099] (C) Dehumidification and regeneration mode In the dehumidification / regeneration mode, as shown in Figs. 1B to 1E, in some of the branch paths 11 (11b), the switching valve 14 (14b) is controlled to cause air to flow into the inflow path 12 (12b) to circulate the air through the air conditioning device 20 (20b), thereby performing dehumidification, and in the remaining branch paths 11 (11a), the switching valve 14 (14a) is controlled to cause air to flow out to the outflow path 13 (13a), thereby heating the air conditioning device 20 (20a) and circulating the air, thereby regenerating the dehumidification layer 26. By executing such a dehumidification / regeneration mode, the air from the vehicle interior or outside the vehicle can be dehumidified by the air conditioning device 20 (20b) while the dehumidification layer 26 of the air conditioning device 20 (20a) can be regenerated. In addition, by switching the air conditioning device 20 that performs dehumidification and regeneration at regular intervals, it is possible to continuously dehumidify the air from the vehicle interior or outside the vehicle and regenerate the dehumidification layer 26.

[0100] In the vehicle air conditioning system according to the embodiment of the present invention, the operation mode of the heat pump cycle 30 can include a heating operation mode and a cooling operation mode. The operation mode of the heat pump cycle 30 can be selected according to a switch operation by the driver or a temperature change detected by various detection units.

[0101] (A) First heating operation mode 1A and 1B, in the first heating operation mode, shutoff valves 37a to 37c are opened and shutoff valves 37d to 37f are closed to form a flow path in which the refrigerant flows sequentially through the compressor 33, the condenser 31, the expansion valve 36a, and the outdoor heat exchanger 34. In Figs. 1A and 1B, the flow path through which the refrigerant flows in this heating operation mode is indicated by a thick line. The refrigerant compressed by the compressor 33 enters the condenser 31 as a high-temperature, high-pressure refrigerant, and dissipates heat by exchanging heat with the air circulating inside the air-conditioning duct 10. The refrigerant leaving the condenser 31 is decompressed and expanded by the expansion valve 36a to become a low-temperature, low-pressure refrigerant, and then exchanges heat with the outside air in the outdoor heat exchanger 34, absorbing heat, and returns to the compressor 33. When this heating operation mode is performed, the air flowing through the air conditioning duct 10 is heated by the condenser 31, and the heated air flows into the vehicle compartment. The temperature of the air flowing into the vehicle compartment can be adjusted by controlling the opening degree of the air mix door 70. This heating operation mode can be implemented when the operation mode of the air conditioning device 20 (20a, 20b) is the dehumidification mode or the dehumidification / regeneration mode, but is preferably implemented in the dehumidification mode.

[0102] (B) Second heating operation mode 1C, in the second heating operation mode, shutoff valves 37b to 37d are opened and shutoff valves 37a, 37e, and 37f are closed to form a flow path through which the refrigerant sequentially flows through compressor 33, condenser 31, expansion valve 36a, exterior heat exchanger 34, and outflow path heat exchanger 35. In FIG. 1C, the flow path through which the refrigerant flows in this heating operation mode is indicated by a thick line. In the heating operation mode, the refrigerant flow path further includes an outflow path heat exchanger 35 disposed downstream of the exterior heat exchanger 34. In the heating operation mode, the refrigerant that has exchanged heat in the exterior heat exchanger 34 and the outflow path heat exchanger 35 is compressed by the compressor 33, and the refrigerant discharged from the compressor 33 is introduced into the condenser 31 to heat the air. Since air that has been heated when the dehumidification layer 26 of the air conditioning device 20 (20a) is regenerated flows through the outflow path 13 (13a), the power consumption (compression rate) of the compressor 33 can be reduced by exchanging heat between the heated air and the refrigerant. In the heating operation mode, the temperature of the air flowing into the vehicle compartment can also be adjusted by controlling the opening degree of the air mix door 70. This heating operation mode can be implemented when the operation mode of the air conditioning device 20 (20a, 20b) is the dehumidification / regeneration mode.

[0103] (C) First cooling operation mode 1D, in the first cooling operation mode, shutoff valves 37a, 37e, and 37f are opened and shutoff valves 37b to 37d are closed to form a flow path in which the refrigerant flows sequentially through compressor 33, outdoor heat exchanger 34, expansion valve 36b, and evaporator 32. In FIG. 1D, the flow path through which the refrigerant flows in this cooling operation mode is indicated by a thick line. The refrigerant compressed by the compressor 33 to a high temperature and pressure is cooled by exchanging heat with outside air in the outdoor heat exchanger 34 and releasing heat. The refrigerant leaving the outdoor heat exchanger 34 is reduced in pressure and expanded in the expansion valve 36b, becoming a low temperature, low pressure refrigerant, which enters the evaporator 32 and absorbs heat by exchanging heat with the air circulating in the air conditioning duct 10. The refrigerant leaving the evaporator 32 returns to the compressor 33. When this cooling operation mode is performed, the air circulating in the air conditioning duct 10 is cooled by the evaporator 32, and the cooled air flows into the vehicle cabin. This cooling operation mode is particularly useful when it is desired to rapidly cool the vehicle cabin (strong cooling operation mode). This cooling operation mode can be implemented when the operation mode of the air conditioning device 20 (20a, 20b) is the dehumidification mode or the dehumidification / regeneration mode.

[0104] (D) Second cooling operation mode In the second cooling operation mode, as shown in Fig. 1E, shutoff valves 37a, 37c, and 37f are opened and shutoff valves 37b, 37d, and 37e are closed to form a flow path in which the refrigerant flows sequentially through the compressor 33, the condenser 31, the expansion valve 36a, the outdoor heat exchanger 34, the expansion valve 36b, and the evaporator 32. In Fig. 1E, the flow path through which the refrigerant flows in this cooling operation mode is indicated by a thick line. In the cooling operation mode, the refrigerant flow path further includes a condenser 31 and an expansion valve 36a downstream of the compressor 33. In the cooling operation mode, the cooling of the air by the evaporator 32 and the heating of the air by the condenser 31 can be adjusted by controlling the opening degree of the air mix door 70, so that the air temperature can be controlled to an optimum temperature.

[0105] It is preferable that the vehicle air conditioning system further includes a detection unit (not shown) capable of detecting fogging of the glass in the vehicle interior, and the control unit 40 executes the dehumidification / regeneration mode when fogging of the glass in the vehicle interior is detected, and executes the dehumidification mode when fogging of the glass in the vehicle interior is not detected. By controlling in this manner, it is possible to efficiently promote the regeneration of the dehumidification layer 26 while suppressing fogging of the glass in the vehicle interior.

[0106] 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.

[0107] In the regeneration mode of the dehumidifying layer 26, in order to promote the desorption of the moisture captured in the dehumidifying layer 26, it is preferable to heat the dehumidifying layer 26 to a temperature equal to or higher than the desorption temperature depending on the type of dehumidifying material. For example, the dehumidifying layer 26 is preferably heated to 70 to 150°C, more preferably to 80 to 140°C, and even more preferably to 90 to 130°C.

[0108] From the viewpoint of stably performing the above control, it is desirable that the air conditioning device 20 is disposed 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 air conditioning device 20 is 60 V or less. Since the honeycomb structure 25 used in the air conditioning device 20 has low electrical resistance at room temperature, the honeycomb structure 25 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 25 is heated becomes large, and therefore it is necessary to use a thicker conductor. [Explanation of symbols]

[0109] 10 Air conditioning duct 11, 11a, 11b Branching Route 12, 12a, 12b Inflow route 13,13a,13b Outflow route 14, 14a, 14b Switching valve 20 Air Conditioning Devices 21 Outer wall 22a First end surface 22b Second end face 23 Cell 24 Bulkhead 25 Honeycomb structure 26 Dehumidification layer 27a, 27b A pair of electrodes 28 Terminals 30 Heat Pump Cycle 31 Capacitor 32 Evaporator 33 Compressor 34 Outdoor heat exchanger 35 Outlet path heat exchanger 36a, 36b Expansion valve 37a~37f Shut-off valves 40 Control section 50 power supply 60 Ventilator 70 Air Mix Door

Claims

1. an air conditioning duct through which air from a vehicle cabin or outside the vehicle can flow and which has two or more branch paths; an air conditioning device disposed in each of the two or more branch paths; a heat pump cycle in which a condenser for exchanging heat between a hot heat of a refrigerant and the air and an evaporator for exchanging heat between a cold heat of the refrigerant and the air are disposed in an air conditioning duct connected to the vehicle compartment downstream of the air conditioning device; a control unit that controls the air conditioning device and the heat pump cycle according to an operation mode; Equipped with the air-conditioning device includes 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, and a dehumidifying layer formed on a surface of the partition walls, The two or more branch paths have an inlet path downstream of the air conditioning device that allows the air to flow into the vehicle cabin, and an outlet path downstream of the air conditioning device that allows the air to flow outside the vehicle, and a switching valve that can switch the flow of the air is provided between the inlet path and the outlet path.

2. The operating mode of the air conditioning device is a dehumidification mode in which the air is dehumidified by controlling the switching valve in all of the branch paths so as to cause the air to flow into the inflow path and circulating the air through the air conditioning device; a dehumidification / regeneration mode in which, in some of the branch paths, the switching valve is controlled to cause the air to flow into the inflow path, thereby circulating the air through the air-conditioning device, thereby performing dehumidification, and, in the remaining branch paths, the switching valve is controlled to cause the air to flow out to the outflow path, thereby heating the air-conditioning device while circulating the air, thereby regenerating the dehumidification layer; 10. The vehicle air conditioning system of claim 1, comprising:

3. The heat pump cycle includes: a compressor that compresses and discharges the refrigerant; an outdoor heat exchanger for exchanging heat between the refrigerant and outdoor air; a heat exchanger in the outflow path for exchanging heat between the refrigerant and the heated air flowing through the outflow path; Further comprising: The operation mode of the heat pump cycle is 3. The vehicle air conditioning system according to claim 1, further comprising a heating operation mode in which the refrigerant that has been heat exchanged in the exterior heat exchanger and the outflow path heat exchanger is compressed by the compressor, and the refrigerant discharged from the compressor is introduced into the condenser to heat the air.

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

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

6. 3. The vehicle air conditioning system according to claim 2, further comprising a detection unit capable of detecting fogging of a glass in the vehicle interior, wherein the control unit executes the dehumidification / regeneration mode when fogging of the glass is detected, and executes the dehumidification mode when fogging of the glass is not detected.

7. The vehicle air conditioning system according to claim 6, wherein the detection unit detects fogging of the glass based on a temperature and a humidity in the vehicle interior.

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