Vehicle air conditioning system

Abstract

A vehicle air conditioning system comprises: an air conditioning duct 10 to allow air to flow from a vehicle interior or a vehicle exterior through it, the air conditioning duct 10 having two or more branched paths 11; an air conditioning device 20 arranged on each of the two or more branched paths 11; a heat pump circuit 30 comprising a condenser 31 for performing heat exchange between the heat of the refrigerant and the air and an evaporator 32 for performing heat exchange between the cold of the refrigerant and the air, the condenser 31 and the evaporator 32 being arranged in the air conditioning duct 10 which is connected to the vehicle interior on a downstream side of the air conditioning device 20; and a control unit 40 for controlling the air conditioning device 20 and the heat pump circuit 30 in response to an operating mode.The air conditioning device 20 comprises: a honeycomb structure 25 having an outer perimeter wall 21 and partitions 24 arranged on an inner side of the outer perimeter wall 21, the partitions 24 defining a plurality of cells 23, each of the cells 23 extending from a first end surface 22a to a second end surface 22b to form a flow path, the partitions 24 being made of a material having a PTC property; and a dehumidification layer 26 formed on each surface of the partitions 24.Each of the two or more branched paths 11 comprises: an inlet path 12 to allow air to flow into the vehicle interior on a downstream side of the air conditioning device 20; and an outlet path 13 to allow air to flow out to the vehicle exterior, and each of the two or more branched paths 11 comprises a switching valve 14 capable of switching the flow of air between the inlet path 12 and the outlet path 13.

Description

Field of application of the invention

[0001] The present invention relates to a vehicle air conditioning system. BACKGROUND OF THE INVENTION

[0002] In various types of vehicles, such as automobiles, there are increasing demands for improving the vehicle interior environment. Specific requirements include reducing the amount of CO2 in the vehicle interior to suppress driver drowsiness, controlling the humidity in the vehicle interior, and removing harmful volatile components in the vehicle interior, such as odor and allergy-causing components. Effective measures for such requirements include ventilation, but ventilation causes a large loss of heating energy in winter, leading to reduced energy efficiency in winter. In particular, a battery electric vehicle (BEV) faces the problem of significantly reducing its cruising range due to energy loss.

[0003] As a method for solving the above problem, Patent Literatures 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 interior, are enclosed by a functional material such as an adsorbent, and the components to be removed are then reacted or desorbed by heating to release them to the vehicle exterior and regenerate the functional material. Such a vehicle air conditioning system requires more contact between the air and the functional material to ensure the performance of enclosing the components to be removed and the ability of the functional material to be heated to a predetermined temperature, thus facilitating the regeneration of the functional material.Regeneration can be carried out, for example, by removing the adsorbed components to be removed through an oxidation reaction and by desorbing and releasing the adsorbed components to be removed. However, both cases require heating the functional material to a suitable temperature depending on the type of adsorbed components to be removed.

[0004] Patent Literature 3 also discloses a heating element comprising: a columnar honeycomb structure having an outer peripheral wall and partition walls arranged on an inner side of the outer peripheral wall, defining a plurality of cells that form flow paths from a first end surface to a second end surface, wherein the partition walls have a PTC property, the partition walls have an average thickness of 0.13 mm or less, and the first end surface and the second end surface have an opening ratio of 0.81 or more. This heating element is used for heating a vehicle interior and is an efficient heating means because the honeycomb structure allows for increasing the heating area. Therefore, using such a heating element as a support for the functional material can contribute to shortening the regeneration time of the functional material.In particular, it is believed that this heating element, because it can be heated by electrical conduction and has a PTC characteristic, can easily heat the functional material while suppressing excessive heat generation and thermal deterioration of the functional material. Furthermore, since the risk of excessive temperature is avoided, safety can be ensured even when setting a small initial resistance to increase the heating rate, and the temperature can be increased in a short period of time.

[0005] On the other hand, an air conditioning system using a heat pump cycle has been proposed from the perspective of improving vehicle heating efficiency (e.g., Patent Literature 4). However, in the air conditioning system using the heat pump cycle, it is difficult to perform heating and dehumidification simultaneously. For example, if heating is performed when the vehicle interior is cold, moisture (water vapor) inside the vehicle is cooled and condenses on the cold glass, which tends to cloud the glass and cause driving problems. Therefore, it is necessary to perform a dehumidification process to dehumidify the air, but the dehumidification process cools the vehicle interior and loses its heating effect. State of the artPatent literature [Patent Literature 1] Japanese Patent Application Publication No. 2020-104774 A [Patent Literature 2] Japanese Patent Application Publication No. 2020-111282 A [Patent Literature 3] WO 2020 / 036067 A1 [Patent Literature 4] German Patent Application Publication No. 102006026359 A SUMMARY OF THE INVENTION Inventive problem

[0006] The present invention was developed to solve the problems described above. An object of the present invention is to provide a vehicle air conditioning system that can simultaneously perform heating and dehumidification using a heat pump cycle. Means of solving the problem

[0007] As a result of intensive studies on vehicle air conditioning systems using heat pump cycles, the present inventor has found that the above problems can be solved by arranging predetermined air conditioning devices in an air conditioning duct having two or more branched paths, providing inflow paths to allow air to flow into the vehicle interior, and providing outflow paths to allow air to flow out of the branched paths on the downstream sides of the air conditioning devices to the vehicle exterior, and arranging a condenser and an evaporator for a heat pump cycle in the air conditioning duct connected to the vehicle interior. That is, the present invention is illustrated as follows:

[0008] [1] A vehicle air conditioning system comprising: an air conditioning duct for allowing air from a vehicle interior or a vehicle exterior to flow therethrough, the air conditioning duct having two or more branched paths; an air conditioning device arranged on each of the two or more branched paths; a heat pump cycle comprising a condenser for performing heat exchange between heat of the coolant and the air and an evaporator for performing heat exchange between cold of the coolant and the air, wherein the condenser and the evaporator are arranged in the air conditioning duct connected to the vehicle interior on a downstream side of the air conditioning device; and a control unit for controlling the air conditioning device and the heat pump circuit in response to an operating mode, wherein the air conditioning device comprises: a honeycomb structure having an outer peripheral wall and partition walls arranged on an inner side of the outer peripheral wall, the partition walls defining a plurality of cells, each of the cells extending from a first end face to a second end face to form a flow path, at least the partition walls being made of a material having a PTC property; and a dehumidification layer formed on each surface of the partition walls, wherein each of the two or more branched paths comprises: an inflow path for allowing the air to flow into the vehicle interior on a downstream side of the air conditioning device; and an outflow path for allowing the air to flow out to the vehicle exterior, and each of the two or more branched paths comprises a switching valve capable of switching the flow of air between the inflow path and the outflow path.

[0009] [2] The vehicle air conditioning system according to [1], wherein the operating mode of the air conditioning device comprises: a dehumidification mode in which the air is dehumidified by controlling the switching valves to allow the air to flow into the inflow path in all branched paths to circulate the air through the air conditioning device; and a dehumidification and regeneration mode in which the air is dehumidified by controlling the switching valve to allow the air in a part of the branched paths to flow into the inflow path to circulate the air through the air conditioning device, and the humidified layer is regenerated by controlling the switching valve to allow the air in the remaining branched paths to flow out to the outflow path to circulate the air through the air conditioning device while heating the air conditioning device.

[0010] [3] The vehicle air conditioning system according to [1] or [2], wherein the heat pump circuit further comprises: a compressor for compressing and releasing the refrigerant; an outdoor heat exchanger for exchanging heat between the refrigerant and outside air; and an internal heat exchanger of the discharge path for exchanging heat between the refrigerant and the heated air flowing through the discharge path; where the operating mode of the heat pump circuit includes: a heating operation mode, wherein the refrigerant that has undergone heat exchange in the outdoor heat exchanger and the indoor heat exchanger of the discharge path is compressed by the compressor, and the refrigerant discharged from the compressor is introduced into the condenser to heat the air.

[0011] [4] The vehicle air conditioning system according to any one of [1] to [3], wherein the material having the PTC property comprises barium titanate as a main component.

[0012] [5] The vehicle air conditioning system according to any one of [1] to [4], wherein the dehumidifying layer further comprises an adsorbent having a function of adsorbing at least one selected from carbon dioxide and volatile components and / or a catalyst.

[0013] [6] The vehicle air conditioning system according to any one of [2] to [5], further comprising a detection section capable of detecting fogging of glass in the vehicle interior, wherein the control unit executes the regeneration and regeneration mode when the fogging of the glass is detected, and the control unit executes the dehumidification mode when the fogging of the glass is not detected.

[0014] [7] The vehicle air conditioning system according to [6], wherein the detection section detects fogging of the glass based on a temperature and a humidity in the vehicle interior. Effects of the invention

[0015] According to the present invention, it is possible to provide a vehicle air conditioning system that can perform heating and dehumidification simultaneously using a heat pump cycle. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1A is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during a dehumidifying / heating operation mode; Fig. 1B is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during a dehumidification and regeneration / heating operation mode; Fig. 1C is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during a dehumidification and regeneration / heating operation mode; Fig. 1D is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during a dehumidification and regeneration / cooling operation mode; Fig. 1E is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during a dehumidification and regeneration / cooling operation mode; Fig. 1F is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during a regeneration / non-cooling / heating operation mode; Fig. 2A is a schematic cross-sectional view of an air conditioning device used in a vehicle air conditioning system according to an embodiment of the present invention, which is parallel to a flow path direction; and Fig. Figure 2B is a schematic cross-sectional view of the air conditioning device taken along the line aa' in Fig. 2A. DETAILED DESCRIPTION OF THE INVENTION

[0016] an air-conditioning duct for allowing air from a vehicle interior or a vehicle exterior to flow therethrough, the air-conditioning duct having two or more branched paths; an air-conditioning device disposed on each of the two or more branched paths; a heat-pump cycle including a condenser for performing heat exchange between heat of the coolant and the air, and an evaporator for performing heat exchange between cold of the coolant and the air, the condenser and the evaporator being disposed in the air-conditioning duct connected to the vehicle interior on a downstream side of the air-conditioning device;and a control unit for controlling the air conditioning device and the heat pump cycle in response to an operation mode, wherein the air conditioning device comprises: a honeycomb structure having an outer peripheral wall and partition walls arranged on an inner side of the outer peripheral wall, the partition walls defining a plurality of cells, each of the cells extending from a first end surface to a second end surface to form a flow path, at least the partition walls being made of a material having a PTC property; and a dehumidification layer formed on each surface of the partition walls; wherein each of the two or more branched paths comprises: an inflow path for allowing the air to flow into the vehicle interior on a downstream side of the air conditioning device;and an exhaust path for allowing the air to flow out to the vehicle exterior, and each of the two or more branched paths includes a switching valve capable of switching the flow of air between the inflow path and the outflow path. With such a configuration, the vehicle air conditioning system according to the present invention can perform heating and dehumidification simultaneously. Therefore, there is no need to alternate heating and dehumidification, and energy efficiency in winter can be improved.

[0017] Embodiments of the present invention will be specifically described below with reference to the drawings. It should be understood that the present invention is not limited to the following embodiments, and corresponding embodiments that appropriately incorporate modifications, improvements, and the like to the following embodiments based on the knowledge of a person skilled in the art without departing from the spirit of the present invention also fall within the scope of the present invention.

[0018] The vehicle air conditioning system according to an embodiment of the present invention can be suitably used for various vehicles, such as automobiles. The vehicle includes, but is not limited to, automobiles and trains. Non-limiting examples of the automobile include a gasoline vehicle, a diesel vehicle, a gas fuel vehicle using CNG (compressed natural gas) or LNG (liquefied natural gas), a fuel cell vehicle, an electric vehicle, and a plug-in hybrid vehicle. The vehicle air conditioning system according to the embodiment of the present invention can be particularly suitably used for a vehicle without an internal combustion engine, such as electric vehicles and electric multiple units.

[0019] Each of the Fig. 1A to Fig. 1F is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention, showing an operating state during each operation mode. In particular, Fig. 1A your dehumidification / heating mode, Fig. 1B and Fig. 1C a dehumidification and regeneration / heating mode, Fig. 1D and Fig. 1E one of the dehumidification and regeneration / cooling modes and Fig. 1F a regeneration / non-cooling / heating operation mode. Fig. 2A is a schematic view of a cross section of an air conditioning device used in a vehicle air conditioning system according to an embodiment of the present invention, which is parallel to a flow path direction. Fig. Figure 2B is a schematic cross-sectional view of the air conditioning device taken along the line aa' in Fig. 2A.

[0020] The vehicle air conditioning system according to an 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. Furthermore, the vehicle air conditioning system may further include: a power source 50; a ventilation blower 60; and an air mix door 70. Each of these components is described in detail below. (1st air conditioning duct 10)

[0021] The air conditioning duct 10 allows air to flow from the vehicle interior or the vehicle exterior therethrough and includes two or more branched paths 11 (11a, 11b). The two or more branched paths 11 (11a, 11b) include inflow paths 12 (12a, 12b) for allowing air to flow into the vehicle interior on the downstream side of the air conditioning devices 20, and outflow paths 13 (13a, 13b) for allowing air to flow out to the vehicle exterior. The two or more branched paths 11 (11a, 11b) are provided with switching valves 14 (14a, 14b) capable of switching the air flow between the inflow paths 12 (12a, 12b) and the outflow paths 13 (13a, 13b). It is preferable that the inflow paths 12 (12a, 12b) converge on the downstream side to form a flow path.

[0022] The number of branched paths 11 of the air-conditioning duct 10 is not limited to a particular one as long as the number is two or more, but it may preferably be 2 to 5, more preferably 2 to 4, and even more preferably 2 to 3.

[0023] The shape and size of the air conditioning duct 10 can be adjusted as needed depending on the type of vehicle and the like, and are also not limited to any particular limitation.

[0024] The switching valves 14 (14a, 14b) can be provided at branched sections between the inflow paths 12 (12a, 12b) and the outflow paths 13 (13a, 13b).

[0025] The switching of the switching valves 14 (14a, 14b) can be carried out, for example, by electrically connecting the control unit 40 to the switching valves 14 (14a, 14b) in a wired or wireless manner and actuating the switches of the switching valves 14 (14a, 14b) by the control unit 40.

[0026] The switching valves 14 (14a, 14b) are also not particularly limited, as long as they are electrically driven and have the function of switching the flow paths, and include electromagnetic valves and electric valves. For example, each of the switching valves 14 (14a, 14b) may include an opening / closing flap supported by a rotating shaft and an actuator, such as a motor, for rotating the rotating shaft. The actuator is configured to be controlled by the control unit 40. (2. Air conditioning device 20)

[0027] The air conditioning devices 20 (20a, 20b) are respectively arranged in the two or more branched paths 11 (11a, 11b).

[0028] Each of the air conditioning devices 20 (20a, 20b) includes: a honeycomb structure including: an outer peripheral wall 21; and partition walls 24 disposed on an inner side of the outer peripheral wall 21 and defining a plurality of cells 23 each extending from a first end surface 22a to a second end surface 22b to form a flow path, wherein at least the partition walls 24 are made of a material having a PTC property; and a dehumidification layer 26 disposed on each 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 terminals 28 connected to the pair of electrodes 27a, 27b.

[0029] When the air flows from the vehicle interior or the vehicle exterior through the air conditioning duct 10 into the air conditioning devices 20, the moisture in the air is trapped (removed) by the dehumidification layer 26 as it flows through the air conditioning devices 20. The air with reduced humidity can then flow into the vehicle interior through the inflow paths 12.

[0030] On the other hand, as the amount of trapped moisture increases, the performance of the dehumidification layer 26 gradually decreases, so the dehumidification layer 26 needs to be regenerated. The regeneration process of the dehumidification layer 26 is performed by applying a voltage to the pair of electrodes 27a, 27b through the power source 50 controlled by the control unit 40 to heat the honeycomb structure 25. Since the dehumidification layer 26 is directly heated by heating the honeycomb structure 25, the moisture trapped in the dehumidification layer 26 is efficiently desorbed or reacted from the dehumidification layer 26 and can be released to the vehicle exterior through the exhaust paths 13. (2-1. Honeycomb structure 25)

[0031] The shape of the honeycomb structure 25 is not particularly limited. For example, an external shape of a cross section of the honeycomb structure 25 orthogonal to the flow path direction of the honeycomb structure 25 (the extension direction of the cells 23) may be polygonal, such as quadrangular (rectangular, square), pentagonal, hexagonal, heptagonal, and octagonal, circular, oval (ovoid, elliptical, elliptical, rounded rectangular, etc.), or the like. The end surfaces (first end surface 22a and second end surface 22b) have the same shape as the cross section. When the cross section and the end surfaces are polygonal, the corners may also be chamfered.

[0032] The shape of each cell 23 is not limited to any particular boundary, but it may be polygonal, such as quadrangular, pentagonal, hexagonal, heptagonal, and octagonal, circular, or oval in the cross-section of the honeycomb structure 25 orthogonal to the flow path direction. These shapes may be present alone or in combination of two or more. Moreover, among these shapes, quadrangular or hexagonal is preferable. By providing the cells 23 with such a shape, it is possible to reduce the pressure loss when the air flows.

[0033] The honeycomb structure 25 may be a bonded honeycomb body comprising a plurality of honeycomb segments and bonding layers that connect the outer peripheral side surfaces of the plurality of honeycomb segments. Using the bonded honeycomb body can increase the total cross-sectional area of ​​the cells 23, which is important for ensuring the air flow rate while suppressing cracking.

[0034] It should be noted that the joining layer can be formed using a joining material. The joining material is not limited to a particular one, but a ceramic material obtained by adding a solvent such as water to form a paste can be used. The joining material may contain a material having the PTC property, or it may contain the same material as the outer peripheral wall 21 and the partition walls 24. In addition to the role of joining the honeycomb segments to each other, the joining material can also be used as an outer peripheral coating material after the honeycomb segments are joined.

[0035] From the viewpoints of ensuring the strength of the honeycomb structure 25, reducing the pressure loss when air flows through the cells 23, ensuring the amount of the supported functional material, and ensuring the contact area with the air flowing inside the cells 23, it is desirable to appropriately combine a thickness of the partition wall 24, a cell density, and a cell pitch (or an opening ratio of the cells 23).

[0036] As used herein, the cell density refers to a value obtained by dividing a number of cells by an area of ​​an end surface (first end surface 22a or second end surface 22b) of the honeycomb structure 25 (the total area of ​​the partition walls 24 and the cells 23 excluding the outer peripheral wall 21).

[0037] As used herein, the cell pitch refers to a value obtained by the following calculation. First, the area of ​​one end surface (first end surface 22a or second end surface 22b) of the honeycomb structure 25 (the total area of ​​the partition walls 24 and the cells 23 excluding the outer peripheral wall 21) is divided by the number of cells to calculate an area per cell. A square root of the area per cell is then calculated, and this is determined as the cell pitch.

[0038] As used herein, the opening ratio of the cells 23 refers to a value obtained by dividing the total area of ​​the cells 23 defined by the partition walls 24 by the area of ​​one end surface 12b (first end surface 22a or second end surface 22b) (the total area of ​​the partition walls 24 and the cells 23 excluding the outer peripheral wall 21) in the cross section orthogonal to the flow path direction of the honeycomb structure 25. 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 account.

[0039] In an embodiment that is advantageous from the point of view of supporting a sufficient amount of functional material, the thickness of the partition wall 24 is 0.300 mm or less, the cell density is 100 cells / cm2 or less, and the cell pitch is 1.0 mm or more. In 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 or less and the cell pitch is 1.2 mm or more. 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 or less and the cell pitch 1.3 mm or more.

[0040] From the viewpoints of ensuring the strength of the honeycomb structure 25 and maintaining a lower electrical resistance, the lower limit of the thickness of the partition wall 24 is preferably 0.010 mm or more, more preferably 0.020 mm or more, and even more preferably 0.030 mm or more.

[0041] From the viewpoints of ensuring the strength of the honeycomb structure 25, maintaining a lower electrical resistance, and increasing a surface area to facilitate reaction, adsorption, and release, the lower limit of the cell density is 30 cells / cm 2 or more and preferably 35 cells / cm 2 or more and more preferably 40 cells / cm 2 or more.

[0042] From the viewpoints of ensuring the strength of the honeycomb structure 25, maintaining a lower electrical resistance, and increasing a surface area to facilitate reaction, adsorption, and release, the upper limit of the cell pitch is 2.0 mm or less, more preferably 1.8 mm or less, and even more preferably 1.6 mm or less.

[0043] In an embodiment that is advantageous in terms of both reducing pressure loss and maintaining strength, the thickness of the partition wall 24 is 0.08 to 0.36 mm, the cell density is 2.54 to 140 cells / cm2, and the opening ratio of the cells 23 is 0.70 or more. In a preferred embodiment, the thickness of the partition wall 24 is also 0.09 to 0.35 mm, the cell density is 15 to 100 cells / cm2, and the opening ratio of the cells 23 is 0.80 or more. In a more preferred embodiment, the thickness of the partition wall 24 is 0.14 to 0.30 mm, the cell density is 20 to 90 cells / cm 2 and the aperture ratio of cells 23 is 0.85 or more.

[0044] 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 still more preferably 0.90 or less.

[0045] Although the thickness of the outer peripheral wall 21 is not limited to any particular one, it is preferably determined based on the following considerations. First, from the viewpoint of reinforcing the honeycomb structure 25, the thickness of the outer peripheral wall 21 is preferably 0.05 mm or more, more preferably 0.06 mm or more, and still more preferably 0.08 mm or more. On the other hand, the thickness of the outer peripheral wall 21 is preferably 1.0 mm or less, more preferably 0.5 mm, more preferably 0.4 mm or less, and still more preferably 0.3 mm or less, from the viewpoint of suppressing the initial current by increasing the electrical resistance and from the viewpoint of reducing the pressure loss when air flows.

[0046] As used herein, the thickness of the outer peripheral wall 21 refers to a length from a boundary between the outer peripheral wall 21 and the outermost cell 23 or the partition wall 24 to a side surface of the honeycomb structure 25 in a normal line direction of the side surface in the cross section orthogonal to the flow path direction of the honeycomb structure 25.

[0047] The length in the flow path direction and the cross-sectional area orthogonal to the flow path direction of the honeycomb structure 25 can be adjusted according to the required size of the air conditioning device 20 and are also not particularly limited. For example, when used in a compact air conditioning device 20, while ensuring a predetermined function, the honeycomb structure 25 can have a length of 2 to 20 mm in the flow path direction and a cross-sectional area of ​​10 cm 2or more orthogonal to the flow path direction. Although the upper limit of the cross-sectional area orthogonal to the flow path direction is not particularly limited, it is, for example, 300 cm 2 or less.

[0048] The partition walls 24 forming the honeycomb structure 25 are made of a material that can be heated by electrical conduction, particularly a material having PTC (Positive Temperature Coefficient) properties. Furthermore, the outer peripheral wall 21 may also be made of the material having PTC properties, as needed, like the partition walls 24. With such a configuration, the dehumidification layer 26 can be directly heated by heat transfer from the heat-generating partition walls 24 (and optionally the outer peripheral wall 21). Furthermore, the material having PTC properties has properties such that when the temperature rises to exceed the Curie point, the resistance value is greatly increased, resulting in difficulty in the flow of electricity.Therefore, when the temperature of the partition walls 24 (and, where applicable, the outer peripheral wall 21) becomes high, the current flowing through them is limited, thereby suppressing excessive heat generation of the honeycomb structure 25. Therefore, it is possible to suppress thermal deterioration of the dehumidification layer 26 due to excessive heat generation.

[0049] The lower limit of the volume resistivity at 25°C of the material having the PTC property 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 obtaining appropriate heat generation. The upper limit of the volume resistivity at 25°C of the material having the PTC property is preferably 30 Ω·cm or less, more preferably 18 Ω·cm or less, and even more preferably 16 Ω·cm or less from the viewpoint of generating heat with a low drive voltage. As used herein, the volume resistivity at 25°C of the material having the PTC property is measured according to JIS K 6271: 2008.

[0050] From the viewpoints of materials that can be heated by electrical conduction and have the PTC property, the outer peripheral wall 21 and the partition walls 24 are preferably made of a material containing barium titanate (BaTiO3) as a main component. Furthermore, this material is more preferably ceramics made of a material containing barium titanate (BaTiO3)-based crystals in which a part of Ba is replaced by a rare earth element as a main component. As used herein, the term "main component" means a component in which a proportion of the component is more than 50 mass% of the total component. The content of BaTiO3-based crystalline particles can be determined by fluorescence X-ray analysis. Other crystalline particles can also be measured by the same method.

[0051] The composition formula of BaTiO3-based crystalline particles in which part of Ba is replaced by the rare earth element can be written as (Ba 1-x A x )TiO3. In the composition formula, the symbol A represents at least one rare earth element, and 0.001 ≤ x ≤ 0.010.

[0052] The symbol A is not limited to any particular component as long as it is a rare earth element. However, it may preferably be 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. The x value is preferably 0.001 or more, and more preferably 0.0015 or more, in terms of suppressing excessively high electrical resistance at room temperature. On the other hand, x is preferably 0.009 or less in terms of preventing the electrical resistance at room temperature from becoming too high due to insufficient sintering.

[0053] The content of BaTiO3-based crystalline particles in which a portion of Ba is replaced by the rare earth element in the ceramic is not limited to a particular component as long as it is determined as the main component, but may preferably be 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 crystalline particles is not limited to a particular component, but may generally be 99 mass%, and preferably 98 mass%.

[0054] The content of BaTiO3-based crystalline particles can be measured by fluorescence X-ray analysis. Other crystalline particles can be measured using the same method.

[0055] From the viewpoint of reducing environmental pollution, it is desirable that the materials used for the outer peripheral wall 21 and the partition walls 24 be substantially free of lead (Pb). Specifically, the outer peripheral wall 21 and the partition walls 24 preferably have a Pb content of 0.01 mass% or less, more preferably 0.001 mass% or less, and even more preferably 0 mass%. The lower Pb content can enable the air heated by contact with the heat-generating partition walls 24 to be safely applied to organisms such as humans. In the outer peripheral wall 21 and the partition walls 24, the Pb content is preferably less than 0.03 mass%, more preferably less than 0.01 mass%, and further preferably 0 mass%, as converted to PbO. The lead content can be determined by ICP-MS (“inductively coupled plasma mass spectroscopy”).

[0056] The material constituting the outer peripheral wall 21 and the partition walls 24 preferably has a Curie point in a temperature range where the resistance value is twice or more of the resistance at room temperature (25°C). When the Curie point is in such a temperature range, the current flowing through the air conditioning device 20 is limited when the air conditioning device 20 reaches a high temperature, so that excessive heat generation of the air conditioning device 20 is effectively suppressed. Therefore, thermal deterioration of the dehumidification layer 26 caused by excessive heat generation can be suppressed.

[0057] The material constituting the outer peripheral wall 21 and the partition walls 24 preferably has a lower limit Curie point of 80°C or more, more preferably 100°C or more, even more preferably 110°C or more, and even more preferably 125°C or more in view of efficiently heating the dehumidifying layer 26. Furthermore, the upper limit of the Curie point is preferably 200°C or more, more preferably 190°C or more, even more preferably 180°C or more, and particularly preferably 150°C or more in view of safety as a component placed in or near the vehicle interior.

[0058] The Curie point of the material constituting the outer peripheral wall 21 and the partition walls 24 can be adjusted by the type of shifter and the amount of shifter added. For example, the Curie point of barium titanate (BaTiO3) is approximately 120°C, but can be shifted to the lower temperature side by replacing some of Ba and Ti with one or more of Sr, Sn, and Zr.

[0059] As used herein, the Curie point is measured using the following method. A sample is attached to a sample holder for measurement mounted in a measuring tank (e.g., MINI-SUBZERO MC-810P, from ESPEC), and a change in the electrical resistance of the sample as a function of temperature change when the temperature is increased by 10 °C is measured using a DC ohmmeter (e.g., Multimeter 3478A, from YOKOGAWA HEWLETT PACKARD, LTD.). Based on an electrical resistance-temperature diagram obtained by the measurement, a temperature at which the resistance value is twice the resistance value at room temperature (20 °C) is defined as the Curie point. (2-2nd pair of electrodes 27a, 27b)

[0060] The pair of electrodes 27a, 27b may be provided on the first end surface 22a and the second end surface 22b, as shown in Fig. 2A. Furthermore, the electrode pair 27a, 27b may be arranged on the outer peripheral wall 21 parallel to the extension direction of the cells 23.

[0061] Applying a voltage between the pair of electrodes 27a, 27b enables the honeycomb structure 25 to generate heat by Joule heating.

[0062] The electrode pair 27a, 27b may use, for example, a metal or alloy containing at least one selected from Cu, Ag, Al, Ni, and Si, although not specifically limited thereto. It is also possible to use an ohmic electrode capable of ohmic contact with the outer peripheral wall 21 and / or the partition walls 24, which have the PTC property. The ohmic electrode may use an ohmic electrode containing, for example, 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. Further, the electrode pair 27a, 27b may have a single-layer structure or may have a laminated structure of two or more layers.When the electrode pair 27a, 27b has the laminated structure of two or more layers, the materials of the respective layers may be of the same type or of different types.

[0063] The thickness of the electrode pair 27a, 27b can be appropriately adjusted according to the method for forming the electrode pair 27a, 27b. The method for forming the electrode pair 27a, 27b includes metal deposition methods such as sputtering, vapor deposition, electrolytic deposition, and chemical deposition. Alternatively, the electrode pair 27a, 27b can be formed by applying an electrode paste and then baking it, or by thermal spraying. Furthermore, the electrode pair 27a, 27b can be formed by bonding metal sheets or alloy sheets.

[0064] For example, each of the thicknesses of the electrode pair 27a, 27b is about 5 to 80 μm for baking the electrode paste, about 100 to 1000 nm for dry plating such as sputtering and evaporation, and about 10 to 100 μm for thermal spraying, and about 5 μm to 30 μm for wet plating such as electrolytic deposition and chemical deposition. Furthermore, when joining the metal sheet or alloy sheet, each of the thicknesses is preferably about 5 to 100 μm. (2-3. Connection 28)

[0065] Terminals 28 are connected to the electrode pair 27a, 27b and are provided on at least a portion of the electrode pair 27a, 27b. Providing terminals 28 facilitates connection to an external power source. Terminals 28 are connected to conductive wires that are connected to the power source 50.

[0066] The terminals 28 may be made of any material, including, but not limited to, a metal, for example. The metal that can be used herein may include single metals, alloys, and the like, but from the standpoint of corrosion resistance, electrical resistivity, and linear expansion coefficient, it may preferably be an alloy containing at least one selected from the group consisting of Cr, Fe, Co, Ni, Cu, Al, and Ti, and more preferably stainless steel, Fe-Ni alloy, and phosphor bronze.

[0067] The size and shape of the terminal 28 are not particularly limited. For example, as shown in Fig. 2A, the terminals 28 may be provided on the entire pair of electrodes 27a, 27b on the outer peripheral wall 21. Further, the terminals 28 may be provided on a part of the pair of electrodes 27a, 27b on the outer peripheral wall 21, or may be provided to extend to a side other than the outer edge of each of the pair of electrodes 27a, 27b on the outer peripheral wall 21. Further, the terminals 28 may be provided on a part of the pair of electrodes 27a, 27b on the partition walls 24, or may be provided to block a part of the cells 23.

[0068] Furthermore, 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.

[0069] The method for connecting the terminals 28 to the pair of electrodes 27a, 27b is not particularly limited, as long as they are electrically connected. For example, they can be connected by diffusion bonding, a mechanical pressing mechanism, welding, or the like. (2-4. Dehumidification layer 26)

[0070] The dehumidification layer 26 can be provided on the surfaces of the partition walls 24 (in the case of the outermost cells 23, the partition walls 24 defining the outermost cells 23 and the outer peripheral wall 21). By thus providing the dehumidification layer 26, the dehumidification layer 26 can be slightly heated during the regeneration process, so that the moisture-adsorbing function of the dehumidification layer 26 can be regenerated.

[0071] The dehumidification layer 26 contains a dehumidification material. The dehumidification material is not limited to any particular one, but a moisture absorbent may be used.

[0072] The moisture adsorbent preferably has a function that can adsorb moisture (water vapor) at -20 to 40°C and release it at an elevated temperature of 60°C or more. Examples of the moisture adsorbent with such a function include aluminosilicate, silica gel, silica, graphene oxide, polymer moisture absorbents, polystyrenesulfonic acid, and metal-organic frameworks (MOFs). These can be used alone or in combination of two or more.

[0073] Examples of the aluminosilicate that can preferably be used herein include AFI-type, CHA-type, or BEA-type zeolite; and porous clay minerals such as allophane and imogolite. Furthermore, it is more preferable that the aluminosilicate be amorphous.

[0074] Examples of the silica gel that can preferably be used herein include Type A silica gel.

[0075] Examples of the polymer moisture adsorbents that can preferably be used herein include those having a polyacrylic acid polymer chain. For example, sodium polyacrylate or the like can be used as the polymer moisture adsorbent.

[0076] 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).

[0077] The dehumidification layer 26 may contain a functional material other than the dehumidification material and / or a catalyst. The functional material other than the dehumidification material is not particularly limited as long as it can perform the desired function, but an adsorbent and 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 use of the catalyst enables the components to be removed to be purified. Furthermore, the adsorbent and the catalyst can be used together to enhance the function of the absorbent for capturing the components to be removed.

[0078] Examples of adsorbents include zeolite, silica gel, activated carbon, alumina, silica, low-crystalline clay, amorphous aluminum silicate complexes, and the like. Some of these components also function as dehumidifying materials. The adsorbent can be used alone or in combination with two or more types.

[0079] The catalyst preferably has a function capable of promoting the oxidation-reduction reaction. Catalysts with such functions include metal catalysts such as Pt, Pd, and Ag, and oxide catalysts such as CeO2 and ZrO2. The catalyst can be used alone or in combination with two or more types.

[0080] Specific examples of the volatile components include ammonia, acetic acid, isovaleric acid, nonenal, formaldehyde, toluene, xylene, paradichlorobenzene, ethylbenzene, styrene, chlorpyrifos, di-n-butyl phthalate, tetradecane and di-2-ethylhexyl phthalate, diazinon, acetaldehyde, 2-(1-methylpropyl)phenyl N-methylcarbamate and the like.

[0081] The thickness of the dehumidifying layer 26 can be determined according to the size of the cells 23 and is also not particularly limited. For example, 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 from the viewpoint of ensuring sufficient contact with air. On the other hand, 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 from the viewpoint of suppressing separation of the dehumidifying layer 26 from the partition walls 24 and the outer peripheral wall 21.

[0082] The thickness of the dehumidification layer 26 is measured using the following method. Each cross section parallel to the flow path direction of the honeycomb structure 25 is cut out, and a cross-sectional image at magnifications of about 50 is taken using a scanning electron microscope or the like. Also, this cross section is made to pass through the center of gravity position in the cross section orthogonal to the flow path of the honeycomb structure 25. The thickness of each dehumidification layer 26, visually recognized from the cross-sectional image, is calculated by dividing the cross-sectional area by the length of the cells 23 in the flow path direction. This calculation is performed for all the dehumidification layers 80 visually recognized from the cross-sectional image, and an average value thereof is determined as the thickness of the dehumidification layer 26.

[0083] From the viewpoint that the functional material and the like have the desired function in the air conditioning device 20, an amount of the dehumidifying layer 26 is preferably 50 to 500 g / L, more preferably 100 to 400 g / L, and even more preferably 150 to 350 g / L, based on the volume of the honeycomb structure 25. Note that the volume of the honeycomb structure 25 is a value determined by the outer dimensions of the honeycomb structure 25. (2-5. Method for manufacturing an air conditioning device 20)

[0084] The method for manufacturing the air conditioning device 20 is not particularly limited and can be performed according to a known method. The method for manufacturing the air conditioning device 20 will be described below by way of illustration.

[0085] A method for manufacturing the honeycomb structure 25 constituting the air conditioning device 20 includes a forming step and a firing step.

[0086] In the forming step, a green body is formed containing a ceramic raw material comprising BaCO3 powder, TiO2 powder, and rare earth nitrate or hydroxide powder to produce a honeycomb formed body having a relative density of 60% or more.

[0087] The ceramic raw material can be obtained by dry mixing the powders so that it has a desired composition.

[0088] The green body can be obtained by adding a dispersion medium, a binder, a plasticizer, and a dispersant to the ceramic raw material and kneading them. The green body may optionally contain additives such as shifters, metal oxides, property enhancers, and conductor powders.

[0089] The mixing amount of the components other than the ceramic raw material is not particularly limited as long as the relative density of the honeycomb molded body is 60% or more.

[0090] As used herein, 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, the relative density can be determined by the following equation: Relative density of the honeycomb body (%) = Density of the honeycomb body (g / cm3) / True density of the entire ceramic raw material (g / cm3) × 100.

[0091] The density of the honeycomb body can be measured using the Archimedes method using pure water as the medium. Furthermore, the true density of the entire ceramic raw material can be determined by dividing the total mass of the respective raw materials (g) by the total volume of the respective raw materials (cm 3 ) can be obtained.

[0092] Examples of the dispersion medium include water or a mixed solvent of water and an organic solvent such as alcohol, and more preferably water.

[0093] Examples of the binder include organic binders such as methylcellulose, hydroxypropoxylcellulose, hydroxyethylcellulose, carboxymethylcellulose, and polyvinyl alcohol. In particular, it is preferable to use methylcellulose in combination with hydroxypropoxylcellulose. The binder can be used alone or in combination with two or more, but it is preferable that the binder does not contain an alkali metal element.

[0094] Examples of the plasticizer include polyoxyalkylene alkyl ethers, polycarboxylic acid-based polymers, and alkyl phosphate esters.

[0095] The dispersant that can be used herein includes surfactants such as polyoxyalkylene alkyl ethers, ethylene glycol, dextrin, fatty acid soaps, and polyalcohols. The dispersant can be used alone or in combination with two or more.

[0096] The honeycomb molded body can be manufactured by extruding the green body. During extrusion, a die with a desired overall shape, cell shape, partition thickness, cell density, and the like can be used.

[0097] The relative density of the honeycomb formed body obtained by extrusion is 60% or more, and preferably 65% ​​or more. By controlling the relative density of the honeycomb formed body within such a range, the honeycomb formed body can be densified and the electrical resistance at room temperature can be reduced. The upper limit of the relative density of the honeycomb formed body is not particularly limited, but it may generally be 80%, and preferably 75%.

[0098] The honeycomb formed body may be dried before the firing step. Non-limiting examples of the drying method include conventionally known drying methods such as hot air drying, microwave drying, dielectric drying, reduced pressure drying, vacuum drying, and freeze drying. Among these, a drying method that combines hot air drying with microwave drying or dielectric drying is preferred because the entire formed body can be dried quickly and uniformly.

[0099] The firing step involves holding the molded body at a temperature of 1150 to 1250 °C and then increasing the temperature to a maximum temperature of 1360 to 1430 °C at a heating rate of 20 to 600 °C / hour and holding the temperature for 0.5 to 10 hours.

[0100] Keeping the honeycomb formed body at the maximum temperature of 1360 to 1430 °C for 0.5 to 10 hours can provide the honeycomb structure 25 containing, as a main component, BaTiO3-based crystal particles in which a part of Ba is replaced by the rare earth element.

[0101] Furthermore, holding at the temperature of 1150 to 1250 °C can allow the Ba2TiO4 crystal particles generated in the firing process to be easily removed so that the honeycomb structure 25 can be densified.

[0102] Furthermore, the heating rate of 20 to 600 °C / hour from the temperature of 1150 to 1250 °C to the maximum temperature of 1360 to 1430 °C can enable 1.0 to 10.0 mass% Ba a Ti 17 O 40 -Crystal particles are formed in the honeycomb structure 25.

[0103] The holding time at 1150 to 1250 °C is not particularly limited, but may preferably be 0.5 to 10 hours. Such a holding time can lead to stable and easy removal of Ba2TiO4 crystal particles generated during the firing process.

[0104] The firing step preferably includes holding at 900 to 950°C for 0.5 to 5 hours while increasing the temperature. Holding at 900 to 950°C for 0.5 to 5 hours can lead to sufficient decomposition of BaCO3, so that the honeycomb structure 25 with a predetermined composition can be easily obtained.

[0105] Before the firing step, a degreasing step can be performed to remove the binder. This degreasing step can preferably be carried out in an air atmosphere to completely decompose the organic components.

[0106] In addition, the atmosphere of the firing step may preferably be the air atmosphere in terms of controlling the electrical properties and the manufacturing cost.

[0107] A firing furnace used in the firing step and the degreasing step is not limited to a particular one, but may be an electric furnace, a gas furnace, or the like.

[0108] The electrode pair 27a, 27b is formed on the honeycomb structure 25 thus obtained. The electrode pair 27a, 27b can be formed by metal deposition methods such as sputtering, vapor deposition, electrolytic deposition, and chemical deposition. Furthermore, the electrode pair 27a, 27b can also be formed by applying an electrode paste and then baking it. Furthermore, the electrode pair 27a, 27b can also be formed by thermal spraying. The electrode pair 27a, 27b can consist of a single layer, but can also consist of a plurality of electrode layers with different compositions. A typical method for forming the electrode pair 27a, 27b is described below.

[0109] First, an electrode slurry containing an electrode material, an organic binder, and a dispersion medium is prepared, and the first end face 22a or the second end face 22b of the honeycomb structure 25 is coated with the slurry. The dispersion medium may 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 at the periphery of the honeycomb structure 25 is removed by blowing and wiping. The slurry may then be dried to form the pair of electrodes 27a, 27b on the first end surface 22a or the second end surface 22b of the honeycomb structure 25.Drying may be performed while the vehicle air conditioner is heated, for example, to a temperature of approximately 120 to 600 °C. Although a series of coating, slurry removal, and drying steps may be performed only once, the steps may be repeated several times to provide the electrode pair 27a, 27b with desired thicknesses.

[0110] Once the terminals 28 are provided, they are then arranged at predetermined positions on the electrode pair 27a, 27b, and the electrode pair 27a, 27b and the terminals 28 are connected to each other. The method described above can be used as a method for connecting the electrode pair 27a, 27b to the terminals 28.

[0111] It should be noted that the terminals 28 may be arranged after forming a dehumidifying layer 26 described below.

[0112] The dehumidifying layer 26 is then formed on the surfaces of the partition walls 24 and the like of the honeycomb structure 25.

[0113] Although the method for forming the dehumidifying layer 26 is not particularly limited, it can be formed, for example, by the following steps. The honeycomb structure 25 is immersed in a slurry containing a dehumidifying material, an organic binder, and a dispersion medium for a predetermined period of time, and excess slurry on the end surfaces and outer periphery of the honeycomb structure 25 is removed by blowing and wiping. The dispersion medium may 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.The slurry can then be dried to form the dehumidifying layer 26 on the surfaces of the partition walls 24. The drying can be performed while heating the honeycomb structure 25, for example, to a temperature of about 120 to 600°C. Although a series of steps of immersion, slurry removal, and drying can be performed only once, the steps can be repeated multiple times to provide the dehumidifying layer 26 with the desired thickness on the surfaces of the partition walls 24 and the like. (3rd heat pump circuit 30)

[0114] The heat pump cycle 30 comprises a condenser 31 and an evaporator 32 arranged in the air conditioning duct 10 connected to the vehicle interior on the downstream side of the air conditioning device 20.

[0115] Condenser 31 can exchange heat between the refrigerant and the air. Specifically, condenser 31 is capable of dissipating heat from the refrigerant flowing through it at elevated temperature and high pressure, and heats the air flowing around condenser 31.

[0116] The evaporator 32 can exchange heat between the cold of the refrigerant and the air. Specifically, the evaporator 32 is capable of absorbing heat from a low-temperature, low-pressure refrigerant flowing through it, and cools the air flowing around the evaporator 32.

[0117] 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 indoor heat exchanger 35 of the discharge path; expansion valves 36a, 36b; and shut-off valves 37a to 37f. Each of these elements is connected via the refrigerant flow path.

[0118] The compressor 33 has a function of compressing and discharging the refrigerant. The compressor 33 has a suction section connected to the heat exchangers (the outdoor heat exchanger 34, the indoor heat exchanger 35 of the discharge path) and a discharge section connected to the condenser 31 via the refrigerant flow path. The compressor 33 is driven by the control unit 40 and discharges the high-temperature, high-pressure refrigerant to the condenser 31 by compressing the refrigerant.

[0119] It should be noted that a known device, such as a gas-liquid separator, may be provided between the compressor 33 and the heat exchanger.

[0120] The outdoor heat exchanger 34 has a function of performing heat exchange between the heat of the refrigerant and the outside air. The outdoor heat exchanger 34 is capable of absorbing heat from the outside air using a low-temperature and low-pressure refrigerant flowing through it, mainly when the heating operation mode is executed, and evaporates the refrigerant by absorbing heat from the outside air. Furthermore, the outdoor heat exchanger 34 can release heat to the outside air using the high-temperature and high-pressure refrigerant flowing through it, and cools the refrigerant by releasing heat to the outside air, mainly when the cooling operation mode is executed.

[0121] The discharge path indoor heat exchanger 35 has a function of performing heat exchange between the heat of the refrigerant and the heated air flowing through the discharge paths 13 (13a, 13b). The discharge path indoor heat exchanger 35 is capable of absorbing the heat from the heated air by the coolant flowing therethrough, mainly when the heating operation mode is executed, and increases the temperature of the refrigerant by absorbing the heat from the outside air.

[0122] Although the Fig. 1A to Fig. 1F shows examples in which the internal heat exchanger 35 of the outflow path is provided only in the outflow path 13a, it should be noted that the internal heat exchanger 35 of the outflow path may also be provided in the outflow path 13b.

[0123] The expansion valves 36a, 36b are throttle valves whose opening degrees can be adjusted by the control unit 40. Specifically, when the heating operation mode is executed, the expansion valve 36a reduces the pressure of the refrigerant discharged from the condenser 31 to expand it, and then discharges the low-temperature, low-pressure refrigerant to the outdoor heat exchanger 34. When the cooling operation mode is executed, the expansion valve 36b further reduces the pressure of the refrigerant from the outdoor heat exchanger 34 to expand it, and then discharges the low-temperature, low-pressure refrigerant to the evaporator 32.

[0124] The shut-off valves 37a to 37f are provided to control the flow path of the refrigerant. The opening and closing of the shut-off valves 37a to 37f are controlled by the control unit 40. (4th control unit 40)

[0125] The control unit 40 controls the air conditioning device 20 and the heat pump cycle 30 depending on the operating mode. Therefore, the control unit 40 is electrically connected to the air conditioning device 20 and the heat pump cycle 30. Specifically, it is connected to a power source 50 for applying a voltage to the pair of electrodes 27a, 27b of the air conditioning device 20, and the power source 50 can be controlled to adjust the heating state of the honeycomb structure 25. Furthermore, the control unit 40 is electrically connected to the shutoff valves 37a to 37f of the heat pump cycle 30 and can control the coolant flow path by opening and closing the shutoff valves 37a to 37f. Furthermore, 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 pressure reduction of the refrigerant by adjusting the opening degrees of the expansion valves 36a, 36b.

[0126] The control unit 40 is electrically connected to a switching valve 14, a ventilation fan 60, an air mixing damper 70, and the like in addition to the air conditioning device 20 and the heat pump cycle 30 and can control these elements.

[0127] The control unit 40 is generally an ECU (motor (electronic) control unit), but is not limited to this. The ECU includes a CPU for performing various calculation processes, a ROM for storing programs and data necessary for its control, a RAM for temporarily storing results of calculations performed by the CPU, and input / output ports for inputting and outputting signals to and from the outside. (5. Power source 50)

[0128] The power source 50 is used to apply a voltage to the pair of electrodes 27a, 27b. The power source 50 is electrically connected to the control unit 40 and adjusts the state of the voltage applied to the pair of electrodes 27a, 27b according to instructions from the control unit 40.

[0129] The power source 50 is not limited to a particular one, and a battery or the like may be used. (6. Ventilation fan 60)

[0130] The ventilation fan 60 is provided to circulate the air through the air conditioning duct 10. The ventilation fan 60 is not particularly limited, and any known ventilation fan may be used.

[0131] The position of the ventilation fan 60 is not limited to a particular position and may be provided on an upstream side of the air conditioning device 20. However, in particular, the ventilation fan may be provided on a downstream side of the condenser 31. (7. Air mixing flap 70)

[0132] The air mix damper 70 is configured to rotate in the air conditioning duct 10 between a heating position that opens a heating path to the condenser 31 and a cooling position that opens a cooling path bypassing the condenser 31. Furthermore, by rotating the air mix damper 70 between the heating position and the cooling position, it can adjust a ratio of the air flowing through the condenser 31 to the air bypassing the condenser 31, thereby adjusting the temperature of the air flowing into the vehicle interior.

[0133] In the vehicle air conditioning system according to the embodiment of the present invention, the operating modes of the air conditioning devices 20 (20a, 20b) may include a dehumidification mode, a regeneration mode, and a dehumidification and regeneration mode. Specifically, the operating modes of the air conditioning devices 20 (20a, 20b) preferably include a dehumidification mode and a dehumidification and regeneration mode. The operating modes of the air conditioning devices 20 (20a, 20b) may be selected according to switching operations by the driver, changes in humidity detected by various detection units, and the like. (A) Dehumidification mode

[0134] As in Fig. As shown in FIG. 1A, the dehumidification mode dehumidifies the air by controlling the switching valves 14 (14a, 14b) in all branched paths 11 (11a, 11b) to allow the air to flow into the inflow paths 12 (12a, 12b) to circulate the air through the air conditioning devices 20 (20a, 20b). By executing such a dehumidification mode, the air of the vehicle interior or the vehicle exterior can be quickly dehumidified. (B) Regeneration mode

[0135] As in Fig. As shown in FIG. 1F, the regeneration mode regenerates the dehumidification layer 26 by controlling the switching valves 14 (14a, 14b) in all branched paths 11 (11a, 11b) to allow the air to flow out to the exhaust paths 13 (13a, 13b) to circulate the air while heating the air conditioning devices 20 (20a, 20b). By executing such a regeneration mode, the regeneration of the dehumidification layer 26 of the air conditioning devices 20 (20a, 20b) can be performed quickly. (C) Dehumidification and regeneration mode

[0136] As in Fig. 1B to Fig. 1E, the dehumidification and regeneration mode dehumidifies the air by controlling the switching valve 14 (14b) in a part of the branched paths 11 (11b) to allow the air to flow into the inflow path 12 (12b) to circulate the air through the air conditioning device 20 (20b), and regenerates the dehumidification layer 26 by controlling the switching valve 14 (14a) in the remaining branched path 11 (11a) to allow the air to flow out to the outflow path 13 (13a) to circulate the air while heating the air conditioning device 20 (20a). By performing such a dehumidification and regeneration mode, it is possible to regenerate the dehumidification layer 26 of the air conditioning device 20 (20a) while the air from the vehicle interior or the vehicle exterior is dehumidified by the air conditioning device 20 (20b).Furthermore, by switching the air conditioning device 20 to perform dehumidification and regeneration at regular intervals, the dehumidification of the air of the vehicle interior or the vehicle exterior and the regeneration of the dehumidification layer 26 can be continuously performed.

[0137] In the vehicle air conditioning system according to the embodiment of the present invention, the operating mode of the heat pump cycle 30 may include a heating operating mode and a cooling operating mode. The operating mode of the heat pump cycle 30 may be selected depending on switching operations by the driver, temperature changes detected by various detection units, and the like. (A) First heating mode

[0138] As in Fig. 1A and Fig. 1B, the first heating operation mode opens the shut-off valves 37a to 37c and closes the shut-off valves 37d to 37f, thereby forming a flow path so that the refrigerant flows sequentially through the compressor 33, the condenser 31, the expansion valve 36a, and the outdoor heat exchanger 34. It should be noted that in Fig. 1A and Fig. 1B the flow path through which the refrigerant flows in this heating operation mode is shown by a thicker line.

[0139] The refrigerant compressed by the compressor 33 enters the condenser 31 as a high-temperature, high-pressure refrigerant, exchanges heat with the air flowing in the air-conditioning duct 10, and releases the heat. The refrigerant leaving the condenser 31 is depressurized and expanded by the expansion valve 36a to form a low-temperature, low-pressure refrigerant, and then exchanges heat with the outside air in the outdoor heat exchanger 34 to absorb the heat and returns to the compressor 33.

[0140] 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 interior. The temperature of the air flowing into the vehicle interior can be adjusted by controlling the opening degree of the air mix door 70.

[0141] This heating operation mode may be performed when the operation mode of the air conditioning devices 20 (20a, 20b) is the dehumidification mode or the dehumidification and regeneration mode, but is particularly preferably performed when the operation mode is the dehumidification mode. (B) Second heating mode

[0142] As in Fig. 1C, the second heating operation mode opens the shutoff valves 37b to 37d and closes the shutoff valves 37a, 37e, 37f, thereby forming a flow path so that the refrigerant flows sequentially through the compressor 33, the condenser 31, the expansion valve 36a, the outdoor heat exchanger 34, and the indoor heat exchanger 35 of the flow path. It should be noted that in Fig. 1C the flow path through which the refrigerant flows in this heating mode is shown by a thicker line.

[0143] In the refrigerant flow path in this heating operation mode, the indoor heat exchanger 35 of the discharge path is further arranged on a downstream side of the outdoor heat exchanger 34. In this heating operation mode, the refrigerant that has undergone heat exchange with the outdoor heat exchanger 34 and the indoor heat exchanger 35 of the discharge path 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 the air heated upon regenerating the humidifying layer 26 of the air conditioning device 20 (20a) flows through the discharge path 13 (13a), the power consumption (compression percentage) of the compressor 33 can be reduced by exchanging heat between the heated air and the refrigerant.In this heating operation mode, the temperature of the air flowing into the vehicle interior can also be adjusted by controlling the opening degree of the air mix door 70.

[0144] This heating operation mode can be performed when the operation mode of the air conditioning devices 20 (20a, 20b) is the dehumidification and regeneration mode. (C) First cooling mode

[0145] As in Fig. 1D, the first cooling operation mode opens the shut-off valves 37a, 37e, 37f and closes the shut-off valves 37b to 37d, thereby forming a flow path so that the refrigerant flows sequentially through the compressor 33, the outdoor heat exchanger 34, the expansion valves 36b, and the evaporator 32. It should be noted that in Fig. 1D the flow path through which the refrigerant flows in this cooling operation mode is shown by a thicker line.

[0146] The refrigerant compressed to a high temperature and high pressure by the compressor 33 is cooled by exchanging heat with the outside air and releasing the heat in the outdoor heat exchanger 34. The refrigerant leaving the outdoor heat exchanger 34 is depressurized and expanded by the expansion valve 36b to form a low-temperature, low-pressure refrigerant, which enters the evaporator 32 and exchanges heat with the air flowing through the air conditioning duct 10 to absorb the heat. The refrigerant leaving the evaporator 32 returns to the compressor 33.

[0147] When the cooling mode is activated, the air flowing through the air conditioning duct 10 is cooled by the evaporator 32, and the cooled air flows into the vehicle interior. The cooling mode is particularly useful when it is desired to quickly cool the vehicle interior (strong cooling mode).

[0148] The cooling operation mode can be performed when the operation mode of the air conditioning devices 20 (20a, 20b) is the dehumidification mode or the dehumidification and regeneration mode. (D) Second cooling mode

[0149] As in Fig. 1E, the second cooling operation mode opens the shut-off valves 37a, 37c, 37f and closes the shut-off valves 37b, 37d, 37e, thereby forming a flow path so that 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. It should be noted that in Fig. 1E the flow path through which the refrigerant flows in this cooling mode is shown by a thicker line.

[0150] The condenser 31 and the expansion valve 36a are further arranged on a downstream side of the compressor 33 in the refrigerant flow path in this cooling operation mode. 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 damper 70, so that the air temperature can be controlled to the optimal temperature.

[0151] The vehicle air conditioning system further includes a detection section (not shown) capable of detecting fogging of the glass in the vehicle interior. It is preferable that the control unit 40 executes the dehumidification and 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. Such control enables the regeneration of the humidification layer 26 to proceed efficiently while suppressing fogging of the glass in the vehicle interior.

[0152] The detection section capable of detecting fogging of the glass in the vehicle interior is not limited to any particular one, but it is preferable to detect fogging of the glass in the vehicle interior based on the temperature and humidity in the vehicle interior. The detection section having such a function can reliably detect fogging of the glass.

[0153] In the regeneration mode of the dehumidification layer 26, the dehumidification layer 26 is preferably heated to a temperature higher than the desorption temperature, depending on the type of dehumidification material, to promote the release of moisture trapped in the dehumidification layer 26. For example, the dehumidification layer 26 is preferably heated to 70 to 150°C, more preferably 80 to 140°C, and even more preferably 90 to 130°C.

[0154] From the viewpoint of stably performing the above control, it is desirable that the air conditioning device 20 be placed at a position close to the vehicle interior. Therefore, from the viewpoint of preventing electric shock and the like, it is preferable that the drive voltage of the air conditioning device 20 be 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 the low drive voltage. Note that the lower limit of the drive voltage is not particularly limited, but it may preferably be 10 V or more. If the drive voltage is less than 10 V, the current during heating of the honeycomb structure 25 becomes large, so the conductor wire should be thick. Description of reference symbols 10 air conditioning duct 11, 11a, 11b branched path 12, 12a, 12b Inflow path 13, 13a, 13b outflow path 14, 14a, 14b switching valve 20 Air conditioning device 21 outer peripheral wall 22a first end face 22b second end face 23 Cell 24 Partition wall 25 Honeycomb structure 26 Dehumidification layer 27a, 27b Electrode pair 28 connection 30 heat pump circuit 31 Capacitor 32 evaporators 33 Compressor 34 outdoor heat exchangers 35 Internal heat exchanger of the outlet path 36a, 36b expansion valve 37a - 37f Shut-off valve 40 Control unit 50 Power source 60 ventilation fans 70 Air mixing flap QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2020 / 036067 A1

[0005]

Claims

[1] A vehicle air conditioning system comprising: an air conditioning duct (10) for allowing air from a vehicle interior or a vehicle exterior to flow therethrough, the air conditioning duct (10) having two or more branched paths (11); an air conditioning device (20) arranged on each of the two or more branched paths (11); a heat pump circuit (30) comprising a condenser (31) for performing heat exchange between heat of the coolant and the air and an evaporator (32) for performing heat exchange between cold of the coolant and the air, wherein the condenser (31) and the evaporator (32) are arranged in the air conditioning duct (10) connected to the vehicle interior on a downstream side of the air conditioning device (20); and a control unit (40) for controlling the air conditioning device (20) and the heat pump circuit (30) in response to an operating mode, wherein the air conditioning device (20) comprises: a honeycomb structure (25) having an outer peripheral wall (21) and partition walls (24) arranged on an inner side of the outer peripheral wall (21), the partition walls (24) defining a plurality of cells (23), each of the cells (23) extending from a first end face (22a) to a second end face (22b) to form a flow path, at least the partition walls (24) being made of a material having a PTC property; and a dehumidification layer (26) formed on each surface of the partition walls (24), wherein each of the two or more branched paths (11) comprises: an inflow path (12) for allowing the air to flow into the vehicle interior on a downstream side of the air conditioning device (20); and an outflow path (13) for allowing the air to flow out to the vehicle exterior, and each of the two or more branched paths (11) comprises a switching valve (14) capable of switching the flow of air between the inflow path (12) and the outflow path (13). [2] The vehicle air conditioning system according to claim 1, wherein the operating mode of the air conditioning device (20) comprises: a dehumidification mode in which the air is dehumidified by controlling the switching valves (14) to allow the air in all branched paths (11) to flow into the inflow path (12) to circulate the air through the air conditioning device (20); and a dehumidification and regeneration mode in which the air is dehumidified by controlling the switching valve (14) to allow the air in a part of the branched paths (11) to flow into the inflow path (12) to circulate the air through the air conditioning device (20), and the humidified layer is regenerated by controlling the switching valve (14) to allow the air in the remaining branched paths (11) to flow out to the outflow path (13) to circulate the air through the air conditioning device (20) while heating the air conditioning device (20). [3] The vehicle air conditioning system according to claim 1 or 2, wherein the heat pump circuit (30) further comprises: a compressor (33) for compressing and discharging the refrigerant; an outdoor heat exchanger (34) for exchanging heat between the refrigerant and outside air; and an internal heat exchanger (35) of the discharge path for exchanging heat between the refrigerant and the heated air flowing through the discharge path (13); wherein the operating mode of the heat pump circuit (30) comprises: a heating operation mode, wherein the refrigerant that has undergone heat exchange in the outdoor heat exchanger (34) and the indoor heat exchanger (35) of the discharge path is compressed by the compressor (33), and the refrigerant discharged from the compressor (33) is introduced into the condenser (31) to heat the air. [4] The vehicle air conditioning system according to any one of claims 1 to 3, wherein the material having the PTC property comprises barium titanate as a main component. [5] The vehicle air conditioning system according to any one of claims 1 to 4, wherein the dehumidifying layer (26) further comprises an adsorbent having a function of adsorbing at least one selected from carbon dioxide and volatile components, and / or a catalyst. [6] The vehicle air conditioning system according to any one of claims 2 to 5, further comprising a detection section capable of detecting fogging of glass in the vehicle interior, wherein the control unit (40) executes the regeneration and regeneration mode when the fogging of the glass is detected, and the control unit (40) executes the dehumidification mode when the fogging of the glass is not detected. [7] The vehicle air conditioning system according to claim 6, wherein the detection section detects fogging of the glass based on a temperature and a humidity in the vehicle interior.

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