Vehicle air conditioning system

Abstract

A vehicle air conditioning system 100, comprising: a dehumidification device 10, comprising: a honeycomb structure 15 with an outer perimeter wall 11 and partitions 14 arranged on an inner surface of the outer perimeter wall 11, the partitions 14 defining a plurality of cells 13, each of the cells 13 extending from a first end surface 12a to a second end surface 12b to form a flow path, at least the partitions 14 being made of a material with a PTC property; a pair of electrodes 16a, 16b provided on the first end surface 12a and the second end surface 12b; and a dehumidification layer 17 formed on a surface of each of the partitions 14; a current source 20 for applying a voltage to the pair of electrodes 16a, 16b; an inlet pipe 30 to allow air to flow from a vehicle interior or vehicle exterior into the dehumidifying device 10;A first outlet pipe 40 for returning the air dehumidified by the dehumidification device 10 to the vehicle interior; a second outlet pipe 50 through which the moisture-containing air released by a regeneration process of the dehumidification device 10 is circulated; and a switching valve 60 provided at a branch section between the first outlet pipe 40 and the second outlet pipe 50, the switching valve 60 being capable of switching the airflow to either the first outlet pipe 40 or the second outlet pipe 50. A separator 70, capable of separating moisture contained in the air by centrifugation, is provided in the second outlet pipe 50. The second outlet pipe 50 merges with the first outlet pipe 40 on a downstream side of the separator 70.

Description

[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 such as odor components and allergens. Effective measures for such requirements include ventilation, but ventilation causes a large loss of heating energy in winter, leading to reduced energy efficiency. In particular, a battery electric vehicle (BEV) has a problem that its cruising range is significantly reduced due to its 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 CO2 and moisture (water vapor) 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 to facilitate the regeneration of the functional material.The regeneration can be carried out, for example, by removing the components to be removed adsorbed on the functional material by an oxidation reaction and by desorbing and releasing the components to be removed adsorbed on the functional material, but both cases require heating the functional material to an appropriate temperature depending on the type of adsorbed components to be removed.

[0004] On the other hand, Patent Literature 3 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 face to a second end face, wherein the partition walls have a PTC (Positive Temperature Coefficient) characteristic, the partition walls have an average thickness of 0.13 mm or less, and the first end face and the second end face 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 since this heating element can be heated by electrical conduction and has a PTC characteristic, it 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. 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 SUMMARY OF THE INVENTION Inventive problem

[0005] In conventional vehicle air conditioning systems, the functional materials are heated during the regeneration process, causing the components to be removed, which are trapped by the functional materials, to react or desorbe, and then be released to the vehicle exterior along with the heated air, resulting in a waste of heat energy. However, when the component to be removed is moisture, a dehumidifying material is used as the functional material. If the moisture released into the air during the regeneration process of the dehumidifying material can be selectively removed, the heated air could be effectively used for space heating and the like.

[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 effectively utilize heated air while selectively removing moisture released into the air during the regeneration process of the dehumidifying material (dehumidifying layer). Means of solving the task

[0007] As a result of intensive studies for vehicle air conditioning systems incorporating dehumidifying devices with dehumidifying layers formed on partition walls of honeycomb structures, the present inventor found that the above-mentioned problems can be solved by providing a separator capable of separating moisture contained in the air by centrifugation in a tube through which the moisture-containing air released by the regeneration process of the dehumidifying device is circulated, and by allowing the tube to be merged with a tube for returning the air to the vehicle interior on a downstream side of the separator. That is, the present invention is illustrated as follows: (1) A vehicle air conditioning system comprising: A dehumidifying device comprising: a honeycomb structure having an outer peripheral wall and partition walls disposed 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; a pair of electrodes provided on the first end face and the second end face; and a dehumidifying layer formed on a surface of each of the partition walls; a power source for applying a voltage to the pair of electrodes; an inlet pipe to allow air from a vehicle interior or exterior to flow into the dehumidifying device; a first exhaust pipe for returning the air dehumidified by the dehumidifying device to the vehicle interior; a second outlet pipe through which the moisture-containing air released by a regeneration process of the dehumidifying device is circulated; and a switching valve provided at a branch portion between the first exhaust pipe and the second exhaust pipe, the switching valve being capable of switching the flow of air to the first exhaust pipe or the second exhaust pipe, wherein a separator capable of separating moisture contained in the air by centrifugation is provided in the second exhaust pipe, and wherein the second outlet pipe is joined to the first outlet pipe on a downstream side of the separator. (2) The vehicle air conditioning system according to (1), wherein the second exhaust pipe is provided with a branch outlet pipe for discharging the moisture separated by the separator. (3) The vehicle air conditioning system according to (2), wherein the second discharge pipe has a horizontal portion and an inclined portion inclined upward in a vertical direction to a downstream side, and wherein the separator is arranged at the inclined portion and the branch outlet pipe is provided at a boundary between the horizontal portion and the inclined portion. (4) The vehicle air conditioning system according to (1), wherein the separator is a cyclone water separator. (5) The vehicle air conditioning system according to any one of (1) to (4), wherein the switching valve is a differential pressure valve capable of switching the flow of air to the first exhaust pipe or the second exhaust pipe, and wherein the vehicle air conditioning system further comprises: a first fan for controlling the differential pressure valve to switch the flow of air to the first discharge pipe; and a second fan for controlling the differential pressure valve to switch the flow of air to the second outlet pipe. (6) The vehicle air conditioning system according to any one of (1) to (5), wherein the first exhaust pipe and the second exhaust pipe have a double pipe structure in which the second exhaust pipe is arranged inside the first exhaust pipe at the branch portion between the first exhaust pipe and the second exhaust pipe. (7) The vehicle air conditioning system according to (5) or (6), wherein the first fan is arranged in the inlet pipe. (8) The vehicle air conditioning system according to any one of (5) to (7), wherein the second fan is arranged in the second exhaust pipe. (9) The vehicle air conditioning system according to any one of (1) to (8), wherein the material having the PTC property comprises barium titanate as a main component. (10) The vehicle air conditioning system according to any one of (1) to (9), 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. (11) The vehicle air conditioning system according to any one of (1) to (10), further comprising a control unit, wherein the control unit can execute: a dehumidification mode in which the vehicle interior is dehumidified by controlling the switching valve to switch the flow of air to the first exhaust pipe; and a regeneration mode in which the dehumidification layer is subjected to a regeneration process by applying a voltage to the pair of electrodes of the dehumidification device and controlling the differential pressure valve to switch the flow of air to the second exhaust pipe. (12) The vehicle air conditioning system according to (11), further comprising a detection section capable of detecting fogging of glass in the vehicle interior, wherein the control section executes the regeneration mode when the fogging of the glass is detected, and the control section executes the dehumidification mode when the fogging of the glass is not detected. (13) The vehicle air conditioning system according to (12), wherein the detection section detects fogging of the glass based on a temperature and a humidity in the vehicle interior. Effects according to the invention

[0008] According to the present invention, it is possible to provide a vehicle air conditioning system that can effectively utilize heated air while selectively removing moisture released into the air during the regeneration process of the dehumidifying material (dehumidifying layer). BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention; Fig. 2A is a schematic view of a cross section of a dehumidifying 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 dehumidification device in Fig. 2A along the line a-a'; Fig. 3 is a schematic configuration view of a vehicle air conditioning system according to another embodiment of the present invention; Fig. 4A is a partially enlarged view showing a state of a differential pressure valve in a dehumidification mode; and Fig. 4B is a partially enlarged view showing a state of a differential pressure valve in a regeneration mode. DETAILED DESCRIPTION OF THE INVENTION

[0009] The vehicle air conditioning system according to the present invention includes: a dehumidifying device comprising: 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 (Positive Temperature Coefficient) property; a pair of electrodes provided on the first end face and the second end face; and a dehumidifying layer formed on a surface of each of the partition walls; a power source for applying a voltage to the pair of electrodes; an inflow pipe for enablingthat air flows from a vehicle interior or a vehicle exterior into the dehumidifying device; a first exhaust pipe for returning the air dehumidified by the dehumidifying device to the vehicle interior; a second exhaust pipe through which the moisture-containing air released by a regeneration process of the dehumidifying device is circulated; and a switching valve provided at a branch portion between the first exhaust pipe and the second exhaust pipe, the switching valve capable of switching the flow of air to the first exhaust pipe or the second exhaust pipe, wherein a separator capable of separating moisture contained in the air by centrifugation is provided in the second exhaust pipe,and wherein the second exhaust pipe is joined to the first exhaust pipe on a downstream side of the separator. With such a configuration, the vehicle air conditioning system according to the present invention can selectively remove moisture released into the air during the regeneration process using the separator. The heated air can then be returned to the vehicle interior, allowing it to be effectively used for purposes such as room heating. Therefore, energy efficiency can be improved, especially in winter.

[0010] Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. It should be understood that the present invention is not limited to the following embodiments, and those embodiments that correspond to reasonable 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 are also within the scope of the present invention.

[0011] 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.

[0012] Fig. 1 is a schematic configuration view of a vehicle air conditioning system according to an embodiment of the present invention. Fig. 2A is a schematic view of a cross section of a dehumidifying 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 dehumidification device in Fig. 2A along the line a-a'.

[0013] As in Fig. 1, a vehicle air conditioning system 100 according to an embodiment of the present invention includes: a dehumidifying device 10; a power source 20; an inflow pipe 30; a first outflow pipe 40; a second outflow pipe 50; a switching valve 60; and a separator 70. In addition, the vehicle air conditioning system 100 may further include a fan 80 for circulating air through pipes (inflow pipe 30, first outflow pipe 40, and second outflow pipe 50) and a control unit 90 for controlling the power source 20, the switching valve 60, the separator 70, the fan 80, and the like.

[0014] As in the Fig. 2A and Fig. 2B, the dehumidifying device 10 includes: a honeycomb structure 15 having an outer peripheral wall 11 and partition walls 14 arranged on an inner side of the outer peripheral wall 11 and defining a plurality of cells 13 each extending from a first end surface 12a to a second end surface 12b to form a flow path; a pair of electrodes 16a, 16b provided on the first end surface 12a and the second end surface 12b; and a dehumidifying layer 17 formed on a surface of each partition wall 14. The power source 20 can apply a voltage to the pair of electrodes 16a, 16b. The inflow pipe 30 can allow the air to flow into the dehumidifying device 10 from the vehicle interior or the vehicle exterior. The first outlet pipe 40 can return the air dehumidified by the dehumidifying device 10 to the vehicle interior.The second exhaust pipe 50 can circulate the moisture-containing air released by the regeneration process of the dehumidifying device 10. The switching valve 60 is provided at a branching portion between the first exhaust pipe 40 and the second exhaust pipe 50 and can switch the flow of air to the first exhaust pipe 40 or the second exhaust pipe 50. The separator 70 can separate moisture contained in the air and is disposed within the second exhaust pipe 50. The second exhaust pipe 50 is joined to the first exhaust pipe 40 on the downstream side of the separator 70.

[0015] In the vehicle air conditioning system 100 having the above configuration, the air flows from the vehicle interior or the vehicle exterior into the dehumidifying device 10 through the inflow pipe 30, and the moisture in the air is trapped (removed) by the dehumidifying layer 17 as the air flows through the dehumidifying device 10. Then, the air with reduced humidity returns to the vehicle interior through the first outflow pipe 40. Such a mode in which the moisture contained in the air from the vehicle interior or the vehicle exterior is removed and returned to the vehicle interior refers to a dehumidification mode.

[0016] On the other hand, the performance of the dehumidification layer 17 gradually decreases as the amount of trapped moisture increases. Therefore, the dehumidification layer 17 also needs to be regenerated. The dehumidification layer 17 is regenerated by applying a voltage to the pair of electrodes 16a, 16b to heat the honeycomb structure 15. Since the dehumidification layer 17 is directly heated by heating the honeycomb structure 15, the moisture trapped by the dehumidification layer 17 is efficiently desorbed or converted and released from the dehumidification layer 17. The released air flows through the second exhaust pipe 50 into the separator 70. The separator 70 selectively separates (removes) the moisture in the air and discharges the heated air. The heated air flows through the second outlet pipe 50, is merged with the first outlet pipe 40 and returns to the vehicle interior.Such a mode in which the dehumidification layer 17 is regenerated refers to a regeneration mode.

[0017] Each component of the vehicle air conditioning system 100 is described in detail below. (1. Dehumidification device 10)

[0018] As in the Fig. 2A and Fig. 2B, the dehumidifying device 10 includes: a honeycomb structure 15 having an outer peripheral wall 11 and partition walls 14 disposed on an inner side of the outer peripheral wall 11, the partition walls 14 defining a plurality of cells 13 each extending from a first end surface 12a to a second end surface 12b to form a flow path; a pair of electrodes 16a, 16b provided on the first end surface 12a and the second end surface 12b; and a dehumidifying layer 17 formed on a surface of each partition wall 14. In addition, the dehumidifying device 10 may further include terminals 18 connected to the pair of electrodes 16a, 16b, if necessary. (1-1. Honeycomb structure 15)

[0019] The shape of the honeycomb structure 15 is not limited to any particular one. For example, an external shape of a cross section of the honeycomb structure 15 orthogonal to the flow path direction (the extension direction of the cells 13) 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 12a and second end surface 12b) have the same shape as the cross section. When the cross section and the end surfaces are polygonal, the corners may also be chamfered.

[0020] The shape of each cell 13 is not limited to a particular one, but may preferably be polygonal, such as quadrangular, pentagonal, hexagonal, heptagonal, and octagonal, circular, or oval in the cross-section of the honeycomb structure 15 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 preferred. By providing the cells 13 with such a shape, it is possible to reduce the pressure loss when the air flows.

[0021] The honeycomb structure 15 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 13, which is important for ensuring the air flow rate while suppressing cracking.

[0022] It should also be noted that the joining layer can be formed using a joining material. Furthermore, the joining material is not limited to any particular one, but may preferably be a ceramic material obtained by adding a solvent such as water to form a paste. The joining material may include a material having the PTC property or the same material as the outer peripheral wall 11 and the partition walls 14. 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 joining the honeycomb segments.

[0023] From the viewpoints of ensuring the strength of the honeycomb structure 15, reducing the pressure loss when air flows through the cells 13, ensuring the amount of the supported functional material, and ensuring the contact area with the air flowing inside the cells 13, it is desirable to appropriately combine a thickness of the partition wall 14, a cell density, and a cell pitch (or an opening ratio of the cells 13).

[0024] 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 12a or second end surface 12b) of the honeycomb structure 15 (the total area of ​​the partition walls 14 and the cells 13 excluding the outer peripheral wall 11).

[0025] 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 12a or second end surface 12b) of the honeycomb structure 15 (the total area of ​​the partition walls 14 and the cells 13 excluding the outer peripheral wall 11) 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.

[0026] As used herein, the opening ratio of the cells 13 refers to a value obtained by dividing the total area of ​​the cells 13 defined by the partition walls 14 by the area of ​​one end surface 12b (first end surface 12a or second end surface 12b) (the total area of ​​the partition walls 14 and the cells 13 excluding the outer peripheral wall 11) of the honeycomb structure 15 in the cross section orthogonal to the flow path direction of the honeycomb structure 15. Note that when calculating the opening ratio of the cells 13, the pair of electrodes 16a, 16b and the dehumidification layer 17 are not taken into account.

[0027] In an embodiment which is advantageous from the point of view of carrying a sufficient amount of functional material, the thickness of the partition wall 14 is 0.300 mm or less, the cell density is 100 cells / cm 2or less, and the cell pitch is 1.0 mm or more. In a preferred embodiment, the thickness of the partition wall 14 is 0.200 mm or less, the cell density is 70 cells / cm2 or less, and the cell pitch is 1.2 mm or more. Furthermore, in a more preferred embodiment, the thickness of the partition wall 14 is 0.130 mm or less, the cell density is 65 cells / cm2 or less, and the cell pitch is 1.3 mm or more.

[0028] From the viewpoints of ensuring the strength of the honeycomb structure 15 and maintaining a lower electrical resistance, the lower limit of the thickness of the partition wall 14 is preferably 0.010 mm or more, more preferably 0.020 mm or more, and still more preferably 0.030 mm or more.

[0029] From the viewpoints of ensuring the strength of the honeycomb structure 15, 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.

[0030] From the viewpoints of ensuring the strength of the honeycomb structure 15, 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.

[0031] In an embodiment that is advantageous both in terms of reducing pressure loss and maintaining strength, the thickness of the partition wall 14 is 0.08 to 0.36 mm, the cell density is 2.54 to 140 cells / cm 2 and the opening ratio of the cells 13 is 0.70 or more. In a preferred embodiment, the thickness of the partition wall 14 is 0.09 to 0.35 mm, the cell density is 15 to 100 cells / cm2, and the opening ratio of the cells 13 is 0.80 or more. In a more preferred embodiment, the thickness of the partition wall 14 is 0.14 to 0.30 mm, the cell density is 20 to 90 cells / cm2, and the opening ratio of the cells 13 is 0.85 or more.

[0032] From the viewpoint of ensuring the strength of the honeycomb structure 15, the upper limit of the opening ratio of the cells 13 is preferably 0.94 or less, more preferably 0.92 or less, and still more preferably 0.90 or less.

[0033] Although the thickness of the outer peripheral wall 11 is not particularly limited, it is preferably determined based on the following considerations. First, from the viewpoint of reinforcing the honeycomb structure 15, the thickness of the outer peripheral wall 11 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 11 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.

[0034] As used herein, the thickness of the outer peripheral wall 11 refers to a length from a boundary between the outer peripheral wall 11 and the outermost cell 13 or the partition wall 14 to a side surface of the honeycomb structure 15 in a normal line direction of the side surface in the cross section orthogonal to the flow path direction.

[0035] The length in the flow path direction and the cross-sectional area orthogonal to the flow path direction of the honeycomb structure 15 can be adjusted according to the required size of the dehumidification device 10 and are not particularly limited. For example, when used in a compact dehumidification device 10 while ensuring a predetermined function, the honeycomb structure 15 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 .

[0036] The partition walls 14 forming the honeycomb structure 15 are made of a material that can be heated by electrical conduction, particularly a material having PTC property. Furthermore, the outer peripheral wall 11 can also be made of the material having PTC property, as needed, like the partition walls 14. With such a configuration, the dehumidification layer 17 can be heated directly by heat transfer from the heat-generating partition walls 14 (and optionally the outer peripheral wall 11). Furthermore, the material having PTC property has properties such that when the temperature rises to exceed the Curie point, the resistance value increases greatly, making it difficult for electricity to flow. When the temperature of the partition walls 14 (and optionally the outer peripheral wall 11) becomes high, the current flowing through them is limited, thereby suppressing excessive heat generation of the honeycomb structure 15.Therefore, it is possible to suppress thermal deterioration of the dehumidification layer 17 due to excessive heat generation.

[0037] 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.

[0038] From the viewpoints of materials that can be heated by electrical conduction and have the PTC property, the outer peripheral wall 11 and the partition walls 14 are preferably made of a material containing barium titanate (BaTiO3) as a main component. Furthermore, this material is more preferably a ceramic 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.

[0039] 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.

[0040] The symbol A is not particularly limited as long as it is the rare earth element, but 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.

[0041] 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 particularly limited as long as it can be designated as the main component, but it 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 particularly limited, but may generally be 99 mass%, and preferably 98 mass%.

[0042] 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.

[0043] From the viewpoint of reducing environmental pollution, it is desirable that the materials used for the outer peripheral wall 11 and the partition walls 14 be substantially free of lead (Pb). Specifically, the outer peripheral wall 11 and the partition walls 14 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 14 to be safely applied to organisms such as humans. In the outer peripheral wall 11 and the partition walls 14, 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 Spectrometry” - ICP-MS, also called inductively coupled plasma mass spectrometry).

[0044] The material constituting the outer peripheral wall 11 and the partition walls 14 preferably has a Curie point in a temperature range where the resistance value is twice or more of the resistance value at room temperature (25°C). When the Curie point is in such a temperature range, the current flowing through the dehumidifying device 10 is limited when the dehumidifying device 10 reaches a high temperature, so that excessive heat generation of the dehumidifying device 10 is effectively suppressed. Therefore, thermal deterioration of the dehumidifying layer 17 caused by excessive heat generation can be suppressed.

[0045] The material constituting the outer peripheral wall 11 and the partition walls 14 preferably has a lower limit Curie point of 80°C or more, more preferably 100°C or more, more preferably 110°C or more, and even more preferably 125°C or more in terms of efficiently heating the dehumidifying layer 17. Furthermore, the upper limit of the Curie point is preferably 200°C or more, more preferably 190°C or more, more preferably 180°C or more, and particularly preferably 150°C or more in terms of safety as a component placed in or near the vehicle interior.

[0046] The Curie point of the material constituting the outer peripheral wall 11 and the partition walls 14 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 the Curie point can be shifted to the lower temperature side by replacing some of the Ba and Ti with one or more of Sr, Sn, and Zr.

[0047] As used herein, the Curie point is measured by the following method. A sample is attached to a measurement sample holder mounted in a measurement 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. (1-2. Pair of electrodes 16a, 16b)

[0048] As in Fig. 2A, the pair of electrodes 16a, 16b is provided on the first end surface 12a and the second end surface 12b.

[0049] Applying a voltage between the pair of electrodes 16a, 16b enables the honeycomb structure 15 to generate heat by Joule heating.

[0050] The pair of electrodes 16a, 16b 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 11 and / or the partition walls 14, 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 pair of electrodes 16a, 16b may have a single-layer structure or a laminated structure of two or more layers.When the pair of electrodes 16a, 16b has the laminated structure of two or more layers, the materials of the respective layers may be of the same type or of different types.

[0051] The thickness of the pair of electrodes 16a, 16b can be appropriately adjusted according to the method for forming the pair of electrodes 16a, 16b. The method for forming the pair of electrodes 16a, 16b includes metal deposition methods such as sputtering, vapor deposition, electrolytic deposition, and chemical deposition. Alternatively, the pair of electrodes 16a, 16b can be formed by applying an electrode paste and then baking it, or by thermal spraying. Further, the pair of electrodes 16a, 16b can be formed by bonding metal sheets or alloy sheets.

[0052] For example, each of the thicknesses of the pair of electrodes 16a, 16b is about 5 to 80 μm for baking the electrode paste, about 100 to 1000 nm for dry plating such as sputtering and vapor deposition, 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. (1-3. Connection 18)

[0053] Terminals 18 are connected to the pair of electrodes 16a, 16b and are provided on at least a portion of the pair of electrodes 16a, 16b. Providing terminals 18 facilitates connection to an external power source. Terminals 18 are connected to conductive wires that are connected to power source 20.

[0054] The terminals 18 may be made of any material, including, but not limited to, a metal. The metal that can be used herein may include single metals, alloys, and the like, but from the standpoint of corrosion resistance, electrical resistance, and linear expansion coefficient, it may preferably be alloys 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.

[0055] The size and shape of the terminal 18 are not particularly limited. For example, as shown in Fig. 2A, the terminals 18 may be provided on the entire pair of electrodes 16a, 16b on the outer peripheral wall 11. Further, the terminals 18 may be provided on a part of the pair of electrodes 16a, 16b on the outer peripheral wall 11, or may be provided to extend to an outer side other than the outer edge of each of the pair of electrodes 16a, 16b on the outer peripheral wall 11. Further, the terminals 18 may be provided on a part of the pair of electrodes 16a, 16b on the partition walls 14, or may be provided to block a part of the cells 13.

[0056] In addition, the thickness of the terminal 18 is not limited to a particular one, but is, for example, 0.01 to 10 mm, typically 0.05 to 5 mm.

[0057] The method for connecting the terminals 18 to the pair of electrodes 16a, 16b is also not limited to any particular one, as long as they are electrically connected. For example, they can be connected by diffusion bonding, a mechanical pressing mechanism, welding, or the like. (1-4. Dehumidification layer 17)

[0058] The dehumidification layer 17 can be provided on the surfaces of the partition walls 14 (in the case of the outermost cells 13, the partition walls 14 defining the outermost cells 13 and the outer peripheral wall 11). By thus providing the dehumidification layer 17, the dehumidification layer 17 can be slightly heated during the regeneration process, so that the moisture-adsorbing function of the dehumidification layer 17 can be regenerated.

[0059] The dehumidification layer 17 contains a dehumidification material. The dehumidification material is not particularly limited, but a moisture absorbent may be used preferably.

[0060] 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 moisture adsorbents 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 with two or more examples.

[0061] 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.

[0062] Examples of the silica gel that can preferably be used herein include Type A silica gel.

[0063] 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.

[0064] 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).

[0065] The dehumidifying layer 17 may contain a functional material other than the dehumidifying material and / or a catalyst. The other functional material is also not particularly limited as long as it can perform the desired function, but an adsorbent, a catalyst, and the like can be preferably used. The adsorbent preferably has a function of adsorbing at least one selected from carbon dioxide and volatile components. Furthermore, the use of the catalyst enables the components to be removed to be purified. Furthermore, the adsorbent and the catalyst can be used together for the purpose of improving the function of the absorbent for capturing the components to be removed.

[0066] 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 act as dehumidifying materials. The adsorbent can be used alone or in combination with two or more types.

[0067] 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.

[0068] 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.

[0069] The thickness of the dehumidifying layer 17 can be determined according to the size of the cells 13 and is not particularly limited. For example, from the viewpoint of ensuring sufficient contact with air, the thickness of the dehumidifying layer 17 is preferably 20 μm or more, more preferably 25 μm or more, and even more preferably 30 μm or more. On the other hand, from the viewpoint of suppressing the separation of the dehumidifying layer 17 from the partition walls 14 and the outer peripheral wall 11, the thickness of the dehumidifying layer 17 is preferably 400 μm or less, more preferably 380 μm or less, and even more preferably 350 μm or less.

[0070] The thickness of the dehumidification layer 17 is measured using the following method. Each cross section parallel to the flow path direction of the honeycomb structure 15 is cut out, and a cross-sectional image at magnifications of about 50 is taken using a scanning electron microscope or the like. This cross section is also made to pass through the center of gravity position in the cross section orthogonal to the flow path of the honeycomb structure 15. The thickness of each dehumidification layer 17 visually recognized from the cross-sectional image is calculated by dividing the cross-sectional area by the length of the cells 13 in the flow path direction. This calculation is performed for all the dehumidification layers 17 visually recognized from the cross-sectional image, and an average value thereof is determined as the thickness of the dehumidification layer 17.

[0071] From the viewpoint that the functional material and the like have the desired function in the dehumidifying device 10, an amount of the dehumidifying layer 17 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 15. Note that the volume of the honeycomb structure 15 is a value determined by the outer dimensions of the honeycomb structure 15. (1-5. Method for manufacturing a dehumidifying device 10)

[0072] The method for manufacturing the dehumidifying device 10 is not limited to any particular method and can be carried out according to any known method. The method for manufacturing the dehumidifying device 10 will be described below by way of illustration.

[0073] A method for manufacturing the honeycomb structure 15 constituting the dehumidifying device 10 includes a forming step and a firing step.

[0074] In the forming step, a green body is formed containing a ceramic raw material including 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.

[0075] The ceramic raw material can be obtained by dry mixing the powders so that it has a desired composition.

[0076] 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.

[0077] Furthermore, 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 formed body is 60% or more.

[0078] 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 molded body (%) = Density of the honeycomb molded body (g / cm3) / True density of the entire ceramic raw material (g / cm3) × 100.

[0079] The density of the honeycomb body can be measured by 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.

[0080] Examples of the dispersion medium include water or a mixed solvent of water and an organic solvent such as alcohol, and more preferably water.

[0081] 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.

[0082] Examples of the plasticizer include polyoxyalkylene alkyl ethers, polycarboxylic acid-based polymers, and alkyl phosphate esters.

[0083] 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.

[0084] 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.

[0085] 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 may generally be 80%, and preferably 75%.

[0086] 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.

[0087] 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.

[0088] 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 15 containing, as a main component, BaTiO3-based crystal particles in which a part of Ba is replaced by the rare earth element.

[0089] 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 15 can be densified.

[0090] 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% Ba6Ti 17 O 40 -Crystal particles are formed in the honeycomb structure 15.

[0091] 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.

[0092] The firing step preferably involves 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 15 with a predetermined composition can be easily obtained.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] The pair of electrodes 16a, 16b are formed on the honeycomb structure 15 thus obtained. The pair of electrodes 16a, 16b can be formed by metal deposition methods such as sputtering, vapor deposition, electrolytic deposition, and chemical deposition. Furthermore, the pair of electrodes 16a, 16b can also be formed by applying an electrode paste and then baking it. Furthermore, the pair of electrodes 16a, 16b can also be formed by thermal spraying. The pair of electrodes 16a, 16b can consist of a single layer or of a plurality of electrode layers with different compositions. A typical method for forming the pair of electrodes 16a, 16b is described below.

[0097] First, an electrode slurry containing an electrode material, an organic binder, and a dispersion medium is prepared, and the first end face 12a or the second end face 12b of the honeycomb structure 15 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 on the periphery of the honeycomb structure 15 is removed by blowing and wiping. The slurry may then be dried to form the pair of electrodes 16a, 16b on the first end face 12a or the second end face 12b of the honeycomb structure 15.Drying may be performed while the vehicle air conditioning system is heated to a temperature of, for example, about 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 pair of electrodes 16a, 16b with desired thicknesses.

[0098] Once the terminals 18 are provided, they are then arranged at predetermined positions on the pair of electrodes 16a, 16b, and the pair of electrodes 16a, 16b and the terminals 18 are connected to each other. The method described above can be used as a method for connecting the pair of electrodes 16a, 16b to the terminals 18.

[0099] It should be noted that the terminals 18 can be arranged after forming a dehumidifying layer 17 described below.

[0100] The dehumidifying layer 17 is then formed on the surfaces of the partition walls 14 and the like of the honeycomb structure 15.

[0101] Although the method for forming the dehumidifying layer 17 is not limited to any particular one, it can be formed, for example, by the following steps. The honeycomb structure 15 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 15 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 may then be dried to form the dehumidifying layer 17 on the surfaces of the partition walls 14.Drying may be performed while heating the honeycomb structure 15 to a temperature of, for example, about 120 to 600°C. Although a series of steps of immersion, slurry removal, and drying may be performed only once, the steps may be repeated several times to provide the dehumidification layer 17 with the desired thickness on the surfaces of the partition walls 14 and the like. (2nd power source 20)

[0102] The power source 20 is used to apply a voltage to the pair of electrodes 16a, 16b. The power source 20 is electrically connected to the control unit 90 and adjusts the state of the voltage applied to the pair of electrodes 16a, 16b according to instructions from the control unit 90.

[0103] The power source 20 is not limited to a particular one and may, for example, be a battery or the like. (3. Inlet pipe 30)

[0104] The inlet pipe 30 is a pipe for allowing the air to flow from the vehicle interior or the vehicle exterior into the dehumidifying device 10.

[0105] The shape and size of the inlet pipe 30 can be adjusted as needed depending on the type of vehicle and are not limited to any particular one. (4. First outlet pipe 40 and second outlet pipe 50)

[0106] Both the first exhaust pipe 40 and the second exhaust pipe 50 are pipes for circulating the air flowing through the dehumidifying device 10. Specifically, the first exhaust pipe 40 is a pipe for returning the air dehumidified by the dehumidifying device 10 to the vehicle interior, and the second exhaust pipe 50 is a pipe for circulating the moisture-containing air released by the regeneration process of the dehumidifying device 10.

[0107] The shape, size, and the like of the first exhaust pipe 40 and the second exhaust pipe 50 can be adjusted as needed depending on the type of vehicle and are not particularly limited. Furthermore, the first exhaust pipe 40 and the second exhaust pipe 50 may be separate pipes from the intake pipe 30 or pipes formed integrally with the intake pipe 30.

[0108] The second exhaust pipe 50 is connected to the first exhaust pipe 40 on the downstream side of the separator 70. Such a configuration allows the heated air, from which the moisture has been removed by the separator 70, to be returned to the first exhaust pipe 40, so that it can be effectively used for room heating and the like.

[0109] As in Fig. 3, the first discharge pipe 40 and the second discharge pipe 50 may have a double-pipe structure in which the second discharge pipe 50 is arranged within the first discharge pipe 40 at a branching portion between the first discharge pipe 40 and the second discharge pipe 50. Such a configuration allows the structure around the branching portion between the first discharge pipe 40 and the second discharge pipe 50 to be made compact and also allows a commercially available differential pressure valve 65, as described below, to be used at the branching portion. It should be noted that Fig. 3 is a schematic configuration view of a vehicle air conditioning system according to another embodiment of the present invention. (5th switching valve 60)

[0110] The switching valve 60 is provided at a branching point between the first exhaust pipe 40 and the second exhaust pipe 50 and has a function of switching the flow of air to the first exhaust pipe 40 or the second exhaust pipe 50.

[0111] The switching of the switching valve 60 can be performed, for example, by electrically connecting the control unit 90 and the switching valve 60 wired or wirelessly and operating the switch of the switching valve 60 using the control unit 90.

[0112] Furthermore, the switching valve 60 is not limited to any particular one, as long as it is electrically driven and has a function of switching flow paths. Examples of the switching valve include electromagnetic valves and electric valves. For example, the switching valve 60 may include an opening and closing door supported by a rotary shaft and an actuator, such as a motor, for rotating the rotary shaft. The actuator is configured to be controllable by the control unit 90.

[0113] The switching valve 60 is preferably a differential pressure valve 65 which can switch the flow of air to the first outlet pipe 40 or the second outlet pipe 50, as shown in Fig. 3. The use of the differential pressure valve 65 eliminates the need to provide the drive section (e.g., the actuator) around the switching valve 60, so that the structure around the branch section can be made compact.

[0114] The differential pressure valve 65 is not limited to a particular one as long as it can be arranged at the branch portion between the first discharge pipe 40 and the second discharge pipe 50 and can open and close the flow path of the first discharge pipe 40 or the second discharge pipe 50 depending on the pressure inside the pipe.

[0115] For example, as in Fig. 4A and Fig. As shown in FIG. 4B, the differential pressure valve 65 includes a base portion 66; opening and closing portions 67a, 67b; and spring portions 68a, 68b connecting the base portion 66 to the opening and closing portions 67a, 67b. The differential pressure valve 65 having such a structure can control the pressure for opening the opening and closing portions 67a, 67b by adjusting the strength of the spring portions 68a, 68b. (6. Separator 70)

[0116] The separator 70 has a function of separating moisture contained in the air through centrifugation. That is, the separator 70 is a gas-liquid separator that utilizes centrifugal force. The separator 70 provides a swirling flow for the moisture-containing air (water vapor) and separates the moisture to the outside and the air to the inside through centrifugal separation. Therefore, by disposing the separator 70 within the second exhaust pipe 50, moisture can be selectively removed from the moisture-containing air released by the regeneration process of the dehumidifying device 10.

[0117] Furthermore, the separator 70 is not limited to any particular one, as long as it has a structure that applies centrifugal force to the circulating air. For example, a swirl vane may be disposed within the second exhaust pipe 50 as the separator 70.

[0118] When the swirl vane is arranged as the separator 70, the moisture separated by centrifugation (condensed water) adheres to the inner wall of the second exhaust pipe 50, so it is preferable that a branch outlet pipe 55 for discharging the moisture separated by the separator 70 to the vehicle outside is provided in the second exhaust pipe 50.

[0119] From the viewpoint of efficiently discharging the moisture separated by centrifugation to the vehicle exterior, it is preferable that the second exhaust pipe 50 has a horizontal portion 51 and an inclined portion 52 inclined upward in a vertical direction toward the downstream side, and the separator 70 is disposed at the inclined portion 52, and that the branch exhaust pipe 55 is provided at the boundary between the horizontal portion 51 and the inclined portion 52.

[0120] The separator 70 used may be a commercially available separator 70 that has a function of separating moisture contained in the air by centrifugation. However, a cyclone water separator may be used specifically as the separator 70. The cyclone water separator generally includes a housing, a cyclone cartridge, and a drain section (moisture outlet section). The cyclone cartridge centrifugally separates the air that has flowed into the housing. The moisture separated by centrifugation can be discharged from the drain section. Therefore, when using the commercially available separator 70, it is not necessary to provide the second exhaust pipe 50 with the inclined section 52 or the branch outlet pipe 55. (7th fan 80)

[0121] The fan 80 is provided to circulate the air through the tubes (the inlet tube 30, the first outlet tube 40, and the second outlet tube 50). The fan 80 is not limited to a particular one, and any known fan may be used.

[0122] The position of the fan 80 is not limited to a particular one and it may be provided in the inflow pipe 30 as shown in Fig. 1, but it may be provided in the exhaust pipe (for example, at a position on a downstream side of the merging portion between the first exhaust pipe 40 and the second exhaust pipe 50, or in both the first exhaust pipe 40 and the second exhaust pipe 50, and the like).

[0123] When the differential pressure valve 65 is used as the switching valve 60 as shown in Fig. 3, it is provided with a first fan 85a for controlling the differential pressure valve 65 to switch the flow of air to the first discharge pipe 40, and a second fan 85b for controlling the differential pressure valve 65 to switch the flow of air to the second discharge pipe 50. Specifically, the first fan 85a is provided to control the opening and closing portion 67a of the differential pressure valve 65 to an open state, and the second fan 85b is provided to control the opening and closing portion 67b of the differential pressure valve 65 to an open state. The first fan 85a and the second fan 85b are not limited to any particular one, and any known fans can be used.

[0124] Here illustrated Fig. 4A is a partially enlarged view showing the state of the differential pressure valve 65 in the dehumidification mode, and Fig. 4B illustrates a partially enlarged view showing the state of the differential pressure valve 65 in the regeneration mode.

[0125] In the dehumidification mode, the differential pressure valve 65 is controlled to switch the flow of air to the first discharge pipe 40, as shown in Fig. 4A by stopping the second fan 85b and activating the first fan 85a. Furthermore, in the regeneration mode, the differential pressure valve 65 is controlled to switch the air flow to the second exhaust pipe 50, as shown in Fig. 4B by stopping the first fan 85a and activating the second fan 85b.

[0126] Furthermore, the position of the first fan 85a is not limited to any particular one, as long as it is a position where the differential pressure valve 65 can be controlled as described above. For example, the first fan 85a may be disposed within the inlet pipe 30. When the first fan 85a is disposed in such a position, the interior of the pipe on the upstream side of the differential pressure valve 65 becomes positively pressurized when the first fan 85a is activated. Due to the positive pressure, only the opening and closing portion 67a of the differential pressure valve 65 is opened, and the air flows into the first outlet pipe 40.

[0127] In order to open only the opening and closing section 67a of the differential pressure valve 65 by the overpressure, the spring section 68a can be set to the strength sufficient to open this section by the overpressure, and the spring section 68b can be set to the strength sufficient not to open this section by the overpressure.

[0128] Furthermore, the first fan 85a may be disposed within the first discharge pipe 40 on the downstream side of the differential pressure valve 65 (at a position upstream of the merging position with the second discharge pipe 50). When the first fan 85a is disposed at such a position, the interior of the first discharge pipe 40 between the differential pressure valve 65 and the first fan 85a becomes negatively pressurized when the first fan 85a is activated. Due to the negative pressure, only the opening and closing portion 67a of the differential pressure valve 65 is opened, and air flows into the first discharge pipe 40. In this case, the strengths of the spring portion 68a and the spring portion 68b of the differential pressure valve 65 may be approximately equal.

[0129] Further, the position of the second fan 85b is not limited to a particular one as long as it is a position in which the differential pressure valve 65 can be controlled as described above.

[0130] For example, the second fan 85b may be disposed within the second exhaust pipe 50 (at a position upstream of the merging position with the first exhaust pipe 40). When the second fan 85b is disposed at such a position, the interior of the second exhaust pipe 50 between the differential pressure valve 65 and the second fan 85b becomes negatively pressurized when the second fan 85b is activated. Due to the negative pressure, only the opening and closing portion 67b of the differential pressure valve 65 is opened, and air flows into the second exhaust pipe 50. (8. Control unit 90)

[0131] The control unit 90 may be provided to control the power source 20, the switching valve 60, the fan 80 (the first fan 85a and the second fan 85b), and the like. The control unit 90 is electrically connected to the power source 20, the switching valve 60, the fan 80 (the first fan 85a and the second fan 85b), and the like.

[0132] The control unit 90 can adjust the heating state of the honeycomb structure 15 by controlling the power source 20 to apply the voltage to the pair of electrodes 16a, 16b of the dehumidifying device 10.

[0133] The control unit 90 can switch the flow of air to the first exhaust pipe 40 or the second exhaust pipe 50 by controlling the switching valve 60.

[0134] The control unit 90 can circulate the air through the pipe by activating the fan 80.

[0135] When the differential pressure valve 65 is used as the switching valve 60, the control unit 90 can be controlled to activate the first fan 85a and switch the air flow past the differential pressure valve 65 to the first exhaust pipe 40. Furthermore, the control unit 90 can be controlled to activate the second fan 85b and switch the air flow past the differential pressure valve 65 to the second exhaust pipe 50.

[0136] The control unit 90 is generally an ECU (Electronic Control Unit), although 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 the results of calculations performed by the CPU, and input / output ports for inputting and outputting signals to and from the outside.

[0137] The control unit 90 can preferably execute both the dehumidification mode in which the vehicle interior is dehumidified by controlling the switching valve 60 to switch the flow of air to the first exhaust pipe 40; and the regeneration mode in which the dehumidification layer 17 is subjected to a regeneration process by applying a voltage to the pair of electrodes 16a, 16b of the dehumidification device 10 and controlling the switching valve 60 to switch the flow of air to the second exhaust pipe 50.In particular, when the switching valve 60 is the differential pressure valve 65, the control unit 90 can preferably operate both a dehumidification mode in which the vehicle interior is dehumidified by activating the first fan 85a and controlling the differential pressure valve 65 to switch the flow of air to the first exhaust pipe 40; and a regeneration mode in which the dehumidification layer 17 is subjected to a regeneration process by activating the second fan 85b, applying a voltage to the pair of electrodes 16a, 16b of the dehumidifying device 10, and controlling the differential pressure valve 65 to switch the flow of air to the second exhaust pipe 50.When such modes are feasible, the moisture contained in the air of the vehicle interior may be removed and returned to the vehicle interior in the dehumidification mode, and the heated air may be returned to the vehicle interior while the moisture trapped by the separator 70 in the dehumidification layer 17 is released in the regeneration mode.

[0138] The vehicle air conditioning system 100 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 90 executes the 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 process of the dehumidification layer 17 to proceed efficiently while suppressing fogging of the glass in the vehicle interior.

[0139] 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.

[0140] In the regeneration mode of the dehumidification layer 17, the dehumidification layer 17 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 17. For example, the dehumidification layer 17 is preferably heated to 70 to 150°C, more preferably 80 to 140°C, and even more preferably 90 to 130°C.

[0141] From the perspective of stably performing the above control, it is desirable that the dehumidifying device 10 be placed at a position close to the vehicle interior. Therefore, from the perspective of preventing electric shock and the like, it is preferable that the driving voltage of the dehumidifying device 10 be 60 V or less. Since the honeycomb structure 15 used in the dehumidifying device 10 has low electrical resistance at room temperature, the honeycomb structure 15 can be heated at the low driving voltage. Note that the lower limit of the driving voltage is not particularly limited, but it may preferably be 10 V or more. If the driving voltage is less than 10 V, the current during heating of the honeycomb structure 15 becomes large, so the conductor wire should be thick. Description of reference symbols 10 Dehumidification device 11 outer peripheral wall 12a first end face 12b second end face 13 Cell 14 Partition wall 15 Honeycomb structure 16a, 16b Pair of electrodes 17 Dehumidification layer 18 connection 20 Power source 30 Inlet pipe 40 first outlet pipe 50 second outlet pipe 51 horizontal section 52 inclined section 55 Branch outlet pipe 60 switching valve 65 Differential pressure valve 66 Base Section 67a, 67b Opening and closing section 68a, 68b spring section 70 Separator 80 fans 85a first fan 85b second fan 90 Control unit 100 vehicle air conditioning system 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] JP 2020-104774 A

[0004] JP 2020-111282 A

[0004] WO 2020 / 036067 A1

[0004] Cited non-patent literature

[0000] JIS K 6271: 2008

[0037]

Claims

[1] A vehicle air conditioning system (100) comprising: a dehumidifying device (10) comprising: a honeycomb structure (15) having an outer peripheral wall (11) and partition walls (14) arranged on an inner side of the outer peripheral wall (11), the partition walls (14) defining a plurality of cells (13), each of the cells (13) extending from a first end face (12a) to a second end face (12b) to form a flow path, at least the partition walls (14) being made of a material having a PTC property; a pair of electrodes (16a, 16b) provided on the first end face (12a) and the second end face (12b); and a dehumidifying layer (17) formed on a surface of each of the partition walls (14); a current source (20) for applying a voltage to the pair of electrodes (16a, 16b); an inlet pipe (30) for allowing air from a vehicle interior or a vehicle exterior to flow into the dehumidifying device (10); a first outlet pipe (40) for returning the air dehumidified by the dehumidifying device (10) to the vehicle interior; a second outlet pipe (50) through which the moisture-containing air released by a regeneration process of the dehumidifying device (10) is circulated; and a switching valve (60) provided at a branching portion between the first discharge pipe (40) and the second discharge pipe (50), the switching valve (60) being capable of switching the flow of air to the first discharge pipe (40) or the second discharge pipe (50), wherein a separator (70) is provided in the second discharge pipe (50) which is capable of separating moisture contained in the air by centrifugation, and wherein the second outflow pipe (50) is joined to the first outflow pipe (40) on a downstream side of the separator (70). [2] The vehicle air conditioning system (100) according to claim 1, wherein the second exhaust pipe (50) is provided with a branch outlet pipe (55) for discharging the moisture separated by the separator (70). [3] The vehicle air conditioning system (100) according to claim 2, wherein the second discharge pipe (50) has a horizontal portion (51) and an inclined portion (52) which is inclined upward in a vertical direction to a downstream side, and wherein the separator (70) is arranged at the inclined portion (52) and the branch outlet pipe (55) is provided at a boundary between the horizontal portion (51) and the inclined portion (52). [4] The vehicle air conditioning system (100) according to claim 1, wherein the separator (70) is a cyclone water separator. [5] The vehicle air conditioning system (100) according to any one of claims 1 to 4, wherein the switching valve (60) is a differential pressure valve (65) capable of switching the flow of air to the first outlet pipe (40) or the second outlet pipe (50), and wherein the vehicle air conditioning system (100) further comprises: a first fan (85a) for controlling the differential pressure valve (65) to switch the flow of air to the first discharge pipe (40); and a second fan (85b) for controlling the differential pressure valve (65) to switch the flow of air to the second outlet pipe (50). [6] The vehicle air conditioning system (100) according to any one of claims 1 to 5, wherein the first exhaust pipe (40) and the second exhaust pipe (50) have a double pipe structure in which the second exhaust pipe (50) is arranged inside the first exhaust pipe (40) at the branch portion between the first exhaust pipe (40) and the second exhaust pipe (50). [7] The vehicle air conditioning system (100) according to claim 5 or 6, wherein the first fan (85a) is arranged in the inlet pipe (30). [8] The vehicle air conditioning system (100) according to any one of claims 5 to 7, wherein the second fan (85b) is arranged in the second exhaust pipe (50). [9] The vehicle air conditioning system (100) according to any one of claims 1 to 8, wherein the material having the PTC property comprises barium titanate as a main component. [10] The vehicle air conditioning system (100) according to any one of claims 1 to 9, wherein the dehumidifying layer (17) further comprises an adsorbent having a function of adsorbing at least one selected from carbon dioxide and volatile components, and / or a catalyst. [11] The vehicle air conditioning system (100) according to any one of claims 1 to 10, further comprising a control unit (90), wherein the control unit (90) can execute: a dehumidification mode in which the vehicle interior is dehumidified by controlling the switching valve (60) to switch the flow of air to the first outlet pipe (40); and a regeneration mode in which the dehumidification layer (17) is subjected to a regeneration process by applying a voltage to the pair of electrodes (16a, 16b) of the dehumidification device (10) and controlling the differential pressure valve (65) to switch the flow of air to the second discharge pipe (50). [12] The vehicle air conditioning system (100) according to claim 11, further comprising a detection section capable of detecting fogging of glass in the vehicle interior, wherein the control section executes the regeneration mode when the fogging of the glass is detected, and the control section executes the dehumidification mode when the fogging of the glass is not detected. [13] The vehicle air conditioning system (100) according to claim 12, wherein the detection section detects fogging of the glass based on a temperature and a humidity in the vehicle interior.

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