Vehicle defogging device

Abstract

To provide a vehicle anti-fogging device enhancing heating efficiency in a vehicle under low temperature environment, and efficiently suppressing fogging on a window glass while suppressing electricity consumption.SOLUTION: An anti-fogging device is provided with a desiccant type dehumidifier, a glass heating device and a control device. The dehumidifier performs a dehumidifying operation adsorbing moisture in a vehicle cabin to a moisture adsorbing part, and a regeneration operation making the moisture adsorbed by heating the dehumidifying part. The glass heating device heats a window glass via a heating wire. The control device controls the operations of the dehumidifier and the glass heating device. When suppressing fogging of the window glass under the situation where the temperature in the vehicle cabin is equal to or lower than a prescribed temperature, the control device operates both the glass heating device and the dehumidifier during a temperature in the vehicle cabin reaches a threshold value temperature, stops the glass heating device at a time when the temperature in the vehicle cabin, and exceeds the threshold value temperature or reduces output of the glass heating device.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an anti-fogging device for suppressing fogging on vehicle window glass. [Background technology]

[0002] Electrical glass heating devices are known as defrosting devices for preventing vehicle windshield fogging. These devices directly heat the windshield, raising the surface temperature of the windshield above the dew point of the air near the windshield, thereby preventing dew from forming on the windshield. While these devices are effective at preventing windshield fogging when the outside air temperature is low, they are no longer effective at preventing fogging when the outside air temperature rises.

[0003] As a countermeasure, an anti-fogging device has been devised that combines dehumidification by an air conditioner using a refrigeration cycle and switches between suppressing fogging by a glass heating device and suppressing fogging by an air conditioner depending on the outside air temperature and humidity (see, for example, Patent Document 1).

[0004] The anti-fogging device described in Patent Document 1 prevents fogging of the window glass by directly heating the window glass using a glass heating device when the outside air temperature is below 0°C, and prevents fogging of the window glass by dehumidifying it using an air conditioning device when the outside air temperature is higher than 0°C. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 60-21097 Summary of the Invention [Problem to be solved by the invention]

[0006] The anti-fogging device described in Patent Document 1 is believed to be able to more quickly prevent window glass from fogging when used in conjunction with dehumidification by an air conditioner, even when the outside air temperature is below 0°C. However, when dehumidification is performed when the outside air temperature is below 0°C, frost may form on the evaporator of the refrigeration cycle, preventing sufficient dehumidification. For this reason, when the air conditioner is operated at low temperatures, outside air is introduced as intake air instead of dehumidification, but this reduces the heating efficiency of the vehicle interior.

[0007] Therefore, we are currently considering adopting a desiccant-type dehumidifier that performs a dehumidification operation in which water vapor in the vehicle cabin is adsorbed by a moisture absorbent, and a regeneration operation in which the moisture absorbent is heated to desorb the adsorbed water vapor.This desiccant-type dehumidifier does not malfunction due to frost formation even when the outside air temperature is low, and can sufficiently reduce the humidity in the vehicle cabin.

[0008] However, because desiccant-type dehumidifiers regenerate the moisture absorbent section by heating it with an electric heater, it takes time for the moisture absorbent section to reach a temperature suitable for regeneration in low-temperature environments. As a result, in low-temperature environments, the dehumidifying capacity of the moisture absorbent section does not increase sufficiently until the temperature inside the vehicle cabin rises sufficiently, making it difficult to prevent window fogging. Furthermore, desiccant-type dehumidifiers require a regenerative electric heater and a blower fan, which consume a large amount of power, in addition to the vehicle's air conditioning system (an air conditioning system using a refrigeration cycle) and glass heating system. Therefore, when a desiccant-type dehumidifier is installed in a vehicle, it is desirable to operate it efficiently within the limited on-board power available.

[0009] Therefore, the present invention aims to provide a vehicle defrosting device that can increase the heating efficiency of the vehicle interior in low-temperature environments and efficiently prevent fogging of the window glass while suppressing power consumption, thereby further improving traffic safety and contributing to the development of sustainable transportation systems. [Means for solving the problem]

[0010] In order to solve the above problems, the vehicle defrosting device according to the present invention employs the following configuration. That is, a vehicle anti-fogging device according to one aspect of the present invention comprises a desiccant-type dehumidifier (e.g., dehumidifier 10 in the embodiments) that performs a dehumidification operation in which water vapor in the vehicle interior is adsorbed by a moisture absorption section (e.g., moisture absorption section 15 in the embodiments) and a regeneration operation in which the moisture absorption section is heated to desorb the adsorbed water vapor, a glass heating device (e.g., glass heating device 60 in the embodiments) that heats a window glass (e.g., window glass 5 in the embodiments) with an electric heating wire (e.g., electric heating wire 6 in the embodiments), and a control device (e.g., control device 50 in the embodiments) that controls the operation of the dehumidifier and the glass heating device, and is characterized in that, when the temperature inside the vehicle interior is below a predetermined temperature and fogging of the window glass is to be suppressed, the control device operates both the glass heating device and the dehumidifier until the temperature inside the vehicle interior reaches a threshold temperature, and stops the glass heating device or reduces the output of the glass heating device when the temperature inside the vehicle interior exceeds the threshold temperature.

[0011] With the above configuration, when suppressing window fogging, the control device controls the glass heating device and the dehumidifier to operate until the temperature inside the vehicle interior reaches a threshold temperature. This allows the dehumidifier to dehumidify the interior air and the glass heating device to heat the window simultaneously. During this time, the air conditioning system can increase heating efficiency by operating with an increased interior air circulation rate. After this, when the temperature inside the vehicle interior exceeds the threshold temperature, the control device controls the glass heating device to stop or reduce its output. At this time, if the interior temperature rises sufficiently, the moisture absorption section of the dehumidifier is efficiently regenerated, increasing the moisture absorption section's ability to dehumidify the vehicle interior. Therefore, even if the glass heating device is stopped or its output is reduced, window fogging can be sufficiently suppressed. Furthermore, when the temperature inside the vehicle compartment exceeds a threshold temperature, the glass heating device is stopped or its output is reduced, thereby making it possible to reduce the power consumption of the vehicle.

[0012] When suppressing fogging of the window glass when the temperature inside the vehicle cabin is below a predetermined temperature, the control device may be configured to gradually reduce the output of the glass heating device after the temperature inside the vehicle cabin exceeds the threshold temperature.

[0013] In this case, the output of the glass heating device is gradually reduced after the temperature inside the vehicle cabin exceeds the threshold temperature, so that even in situations where the window glass is cooled by the wind when the vehicle is traveling at high speed, for example, the temperature of the window glass can be prevented from dropping suddenly and causing the window glass to fogging up.

[0014] When suppressing fogging of the window glass when the temperature inside the vehicle interior is below a predetermined temperature, the control device may reduce the output of the glass heating device and increase the heating output to the moisture absorption section of the dehumidifying device after the temperature inside the vehicle interior exceeds the threshold temperature.

[0015] In this case, by increasing the heating output to the moisture absorber after the temperature inside the vehicle exceeds the threshold temperature, the regeneration capacity of the moisture absorber can be improved, thereby increasing the dehumidification capacity of the moisture absorber. In this case, increasing the heating output to the moisture absorber increases power consumption, but by reducing the output of the glass heating device, the increase in power consumption of the entire vehicle can be suppressed.

[0016] In addition, a vehicle anti-fogging device according to another aspect of the present invention comprises a desiccant-type dehumidifier (e.g., dehumidifier 10 in the embodiments) that performs a dehumidification operation in which water vapor in the vehicle interior is adsorbed by a moisture absorption section (e.g., moisture absorption section 15 in the embodiments) and a regeneration operation in which the moisture absorption section is heated to desorb the adsorbed water vapor, a glass heating device (e.g., glass heating device 60 in the embodiments) that heats a window glass (e.g., window glass 5 in the embodiments) with an electric heating wire (e.g., electric heating wire 6 in the embodiments), and a control device (e.g., control device 50 in the embodiments) that controls the operation of the dehumidifier and the glass heating device, wherein the control device operates both the glass heating device and the dehumidifier when the temperature in the vehicle interior is below a predetermined temperature and fogging of the window glass is to be suppressed, and stops the glass heating device or reduces the output of the glass heating device when a predetermined time has elapsed since the operation of the glass heating device and the dehumidifier was started.

[0017] With the above configuration, to suppress window fogging, the control device operates the glass heating device and the dehumidifier, and after a predetermined time has elapsed since their operation started, the glass heating device is stopped or its output is reduced. While both the glass heating device and the dehumidifier are operating, window fogging is efficiently suppressed. During this time, the air conditioner can increase heating efficiency by operating with an increased indoor air circulation rate. Furthermore, by the time the glass heating device is stopped or its output is reduced after the predetermined time has elapsed, the indoor temperature is sufficiently high. Therefore, even if the glass heating device is stopped or its output is reduced, the moisture absorption section of the dehumidifier can be efficiently heated. As a result, window fogging is suppressed. In addition, by stopping the glass heating device or reducing its output after a predetermined time has elapsed since the glass heating device and dehumidifier started operating, it is possible to reduce the vehicle's power consumption. [Effects of the Invention]

[0018] The vehicle defrosting device of the present invention rapidly suppresses fogging of the window glass by simultaneously operating the glass heating device and the dehumidifying device until the temperature in the vehicle interior has risen sufficiently to fully regenerate the moisture absorption portion of the dehumidifying device, and then stops the glass heating device or reduces its output when the moisture absorption portion of the dehumidifying device has fully regenerated.As a result, the vehicle defrosting device of the present invention can increase the heating efficiency of the vehicle interior in low-temperature environments and efficiently suppress fogging of the window glass while reducing power consumption.Therefore, adoption of the vehicle defrosting device of the present invention can further improve transportation safety and contribute to the development of sustainable transportation systems. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic side view of a vehicle interior that employs an anti-fogging device according to an embodiment; [Figure 2] 1 is a schematic diagram of an anti-fogging device according to an embodiment, showing a dehumidifying device in cross section; [Figure 3] FIG. 2 is a cross-sectional view showing the internal structure of the moisture absorbing device of the dehumidifying apparatus according to the embodiment. [Figure 4] 4 is a characteristic diagram showing changes in the room temperature, the heater power of the dehumidifier, and the power of the glass heating device when the anti-fogging device of the first embodiment is used. FIG. [Figure 5] FIG. 10 is a characteristic diagram showing changes in the room temperature, the heater power of the dehumidifier, and the power of the glass heating device when the anti-fogging device of the second embodiment is used. [Figure 6] FIG. 10 is a characteristic diagram showing changes in the room temperature, the heater power of the dehumidifier, and the power of the glass heating device when the anti-fogging device of the third embodiment is used. [Figure 7] FIG. 10 is a characteristic diagram showing changes in the room temperature, the heater power of the dehumidifier, and the power of the glass heating device when the defrosting device of the fourth embodiment is used. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic side view of the interior of a vehicle compartment 2 of a vehicle 1 that employs an anti-fogging device 100 of this embodiment, and FIG. 2 is a schematic configuration diagram of the anti-fogging device 100, showing a cross section of the dehumidifier 10. The dehumidifying device 100 includes a desiccant-type dehumidifying device 10 that dehumidifies the interior of the vehicle compartment 2, a glass heating device 60 that heats a window glass 5 (e.g., a windshield) of the vehicle with an electric heating wire 6, and a control device 50 that controls the dehumidifying device 10 and the glass heating device 60. As shown in FIG. 1, the dehumidifying device 10 is disposed, for example, at the lower rear of the vehicle compartment 2, and blows out the air in the vehicle compartment 2 that has been adsorbed by a moisture absorber 15 (see FIG. 2) toward the front of the vehicle compartment 2. The water vapor absorbed by the moisture absorber 15 is discharged to the outside of the vehicle 1 by a regeneration operation of the dehumidifying device 10.

[0021] As shown in Figure 2, the dehumidifier 10 includes a pair of moisture absorption devices 11A, 11B that circulate air within the vehicle interior 2 and adsorb water vapor (moisture) in the air, a rectangular cylindrical housing 12 that houses the moisture absorption devices 11A, 11B, an upstream duct block 13 for introducing air that is connected to one end of the housing 12, and a downstream duct block 14 for discharging air that is connected to the other end of the housing 12.

[0022] Moisture absorbing devices 11A and 11B each have a rectangular cylindrical case with a moisture absorbing section 15 arranged therein that allows air to pass through. The two moisture absorbing devices 11A and 11B have the same structure. Hereinafter, when distinguishing between the two moisture absorbing devices 11A and 11B, one will be referred to as the first moisture absorbing device 11A and the other will be referred to as the second moisture absorbing device 11B.

[0023] The upstream duct block 13 has a collecting passage 13d having an inlet 13a and branch passages 13b and 13c branching from the collecting passage 13d. A blower fan 18 (air blower) is installed in the collecting passage 13d to introduce air from the vehicle cabin into the first and second moisture absorbent devices 11A and 11B. The branch passages 13b and 13c are connected to the first and second moisture absorbent devices 11A and 11B, respectively. A distribution door 40 is installed downstream of the blower fan 18 in the collecting passage 13d to adjust the ratio of air flowing from the collecting passage 13d into the branch passages 13b and 13c. The distribution door 40 is rotated by an actuator 35 such as a motor. The actuator 35 is controlled by a control device 50. The ratio of air flowing from the blower fan 18 into the first moisture absorbent device 11A and the second moisture absorbent device 11B can be adjusted by the control of the actuator 35 by the control device 50.

[0024] The downstream duct block 14 has two communication passages 14a, 14b that communicate with the first and second moisture absorbent devices 11A, 11B in the housing 12, an interior return port 14c that returns the regenerated air into the vehicle cabin 2, and an exhaust port 14d that exhausts the air (air containing water vapor) used to regenerate the moisture absorbers 15 in the first and second moisture absorbent devices 11A, 11B to the outside of the vehicle. Doors 42a, 42b that constitute the flow path switching mechanism 19 are disposed downstream of each of the communication passages 14a, 14b. The doors 42a, 42b open and close the interior return port 14c and the exhaust port 14d by actuation of an actuator (not shown). The doors 42a, 42b selectively connect each of the communication passages 14a, 14b to either the interior return port 14c or the exhaust port 14d. In the dehumidifier 10 of this embodiment, the flow path switching mechanism 19 switches the flow paths in the downstream duct block 14, so that the first moisture absorbent device 11A and the second moisture absorbent device 11B can be alternately switched between moisture absorption and regeneration. In FIG. 2, for the sake of convenience, two indoor return ports 14c and two discharge ports 14d are shown connected to the communication passages 14a and 14b, respectively, to make it easier to understand the structure of the passages.

[0025] 3 is a cross-sectional view of the first moisture absorbing device 11A taken in a direction perpendicular to the air flow. The structure of the first moisture absorbing device 11A will be described below, but the second moisture absorbing device 11B has a similar structure. As shown in FIG. 3, the moisture absorbent section 15 inside the first moisture absorbing device 11A is a breathable sheet 20 folded into pleats, on which a predetermined moisture absorbent is carried. The moisture absorbent carried by the sheet 20 may be, for example, Huxley (registered trademark), zeolite, silica gel, or a polymer adsorbent, which exhibits high moisture absorption performance in a predetermined humidity environment. The moisture absorbent section 15 of this embodiment employs a structure in which the sheet 20 carrying the moisture absorbent is in direct contact with a heater 21, which will be described later, but the material carrying the moisture absorbent is not limited to the sheet 20. The material carrying the moisture absorbent may be, for example, a honeycomb-shaped substrate or a mesh-shaped substrate, as long as it can be heated by passing electricity through it.

[0026] The first moisture absorbent device 11A is equipped with a heater 21 (heating unit) that is in direct contact with the moisture absorbent unit 15 and heats the moisture absorbent unit 15. The heater 21 is a plate-shaped heater that extends in the direction along the air flow and is in direct contact with the moisture absorbent unit 15 over almost the entire longitudinal area. The heater 21 is switched on and off under the control of the control device 50. The heater 21 can also adjust the heating temperature by adjusting the power. The heaters 21 of the first moisture absorbent device 11A and the second moisture absorbent device 11B are turned off during a dehumidification operation that dehumidifies the air in the vehicle compartment 2, and are turned on during a regeneration operation that regenerates the moisture absorbent unit 15 (desorbs the water vapor adsorbed by the moisture absorbent unit 15).

[0027] The blower fan 18 is controlled by a control device 50 so that the power can be turned on and off and the output can be adjusted. The actuator 35 of the distribution door 40 is controlled by the control device 50, thereby adjusting the amount of air distributed to the first moisture absorbing device 11A and the second moisture absorbing device 11B.

[0028] 2, an outside air temperature sensor 51 that detects the temperature of the outside air (outside the vehicle), an outside air humidity sensor 52 that detects the relative humidity of the outside air, an inside air temperature sensor 53 that detects the temperature of the inside air (inside the vehicle), an inside air humidity sensor 54 that detects the relative humidity of the inside air, etc. are connected to the input side of the control device 50. The control device 50 controls the operation of the dehumidifier 10 and the glass heating device 60 based on this information.

[0029] [First embodiment] FIG. 4 is a characteristic diagram showing the changes in the room temperature, the heater power of the dehumidifier 10, and the power of the glass heating device 60 when the anti-fogging device 100 of this embodiment is used. The output of the heater 21 of the dehumidifier 10 can be switched between three levels: high, medium, and low, and the output of the heating wire 6 of the glass heating device 60 can be switched between two levels: high and low. However, when the anti-fogging device 100 is operating in a low-temperature environment, the heater 21 of the dehumidifier 10 is used in a medium output mode (Mid), and the heating wire 6 of the glass heating device 60 is used in a high output mode (Hi).

[0030] When the temperature inside the vehicle cabin is below a predetermined temperature (low temperature environment), the control device 50 controls the dehumidifier 10 and the glass heating device 60 of the defrosting device 100 as follows to suppress fogging of the window glass 5. In this specification, "suppressing fogging of window glass" includes suppressing the occurrence of fogging on window glass and removing fogging that has occurred on window glass. For example, when the control device 50 determines that the temperature inside the vehicle cabin is below a predetermined temperature, such as when the vehicle is started, the control device 50 operates the dehumidifier 10 and the glass heating device 60 in the above-mentioned predetermined output mode until the temperature inside the vehicle cabin reaches the threshold temperature T1. When the dehumidifier 10 and the glass heating device 60 are thus operated, the dehumidifier 10 dehumidifies the vehicle cabin, and the glass heating device 60 directly heats the window glass 5.

[0031] At this time, in the dehumidifier 10, the moisture absorbent 15 of one of the moisture absorbent devices 11A or 11B is heated by the heater 21 to perform regeneration operation, while the moisture absorbent 15 of the other moisture absorbent device 11B or 11A removes moisture from the vehicle interior. While the temperature inside the vehicle interior is low, the temperature rise of the moisture absorbent 15 is slow during regeneration operation of the moisture absorbent 15, and the dehumidification efficiency of the vehicle interior during dehumidification operation is low, but as the temperature inside the vehicle interior rises, the dehumidification efficiency of the vehicle interior during dehumidification operation gradually increases. Note that as dehumidification of the vehicle interior progresses through the dehumidification operation of the dehumidifier 10, the dew point temperature of the air near the window glass 5 gradually decreases. Until the temperature inside the vehicle cabin reaches the threshold temperature T1, the glass heating device 60 directly heats the window glass 5, thereby raising the surface temperature of the window glass 5 (surface temperature inside the vehicle cabin) above the dew point temperature of the air near the window glass 5. This prevents the window glass 5 from fogging up.

[0032] After that, the temperature inside the vehicle cabin gradually increases, and when the temperature inside the vehicle cabin reaches the threshold temperature T1, the control device 50 stops the operation of the glass heating device 60. At this time, the dehumidifier 10 continues to operate. When the temperature inside the vehicle cabin reaches or exceeds the threshold temperature T1, the temperature of the moisture absorbent 15 of the dehumidifier 10 is raised early by heating with the heater 21 during regeneration of the moisture absorbent 15. As a result, the regeneration efficiency of the moisture absorbent 15 is improved, and the dehumidification efficiency during dehumidification operation is also improved. This allows moisture inside the vehicle cabin to be efficiently removed, and the window glass 5 does not fogging up even when the glass heating device 60 is stopped. Furthermore, after the temperature inside the vehicle compartment reaches or exceeds the threshold temperature T1, the operation of the glass heating device 60 is stopped, thereby reducing the power consumption for operating the glass heating device 60.

[0033] As described above, the anti-fogging device 100 of this embodiment can efficiently suppress fogging of the window glass 5 by simultaneously operating the glass heating device 60 and the dehumidifier 10 until the temperature inside the vehicle cabin reaches the threshold temperature T1. Furthermore, when the temperature inside the vehicle cabin rises above the threshold temperature T1 and the moisture absorption section 15 of the dehumidifier 10 is sufficiently regenerated, the defroster 100 stops the operation of the glass heating device 60. This makes it possible to reduce power consumption due to the operation of the glass heating device 60. Furthermore, since the dehumidifier 100 continues to operate the dehumidifier 10 at all times from the start, it is possible to suppress fogging of the window glass 5 even when the inside air circulation rate of the air conditioner is kept high. Therefore, by performing heating operation with the air conditioner keeping the inside air circulation rate high, it is possible to improve the heating efficiency of the vehicle interior. Therefore, when the defrosting device 100 of this embodiment is employed, it is possible to improve the heating efficiency of the vehicle interior in a low-temperature environment and quickly defog the window glass 5 while suppressing power consumption. Therefore, employing this defrosting device 100 can further improve traffic safety and contribute to the development of a sustainable transportation system.

[0034] [Second embodiment] FIG. 5 is a characteristic diagram showing the changes in the room temperature, the heater power of the dehumidifier 10, and the power of the glass heating device 60 when the anti-fogging device 100 of this embodiment is used. In this embodiment, when the anti-fogging device 100 is operating in a low temperature environment, the heater 21 of the dehumidifier 10 is used in a medium output mode (Mid), and the heating wire 6 of the glass heating device 60 is used in a high output mode (Hi) and a low output mode (Lo).

[0035] When the temperature inside the vehicle cabin is below a predetermined temperature (low temperature environment), the control device 50 controls the dehumidifier 10 and the glass heating device 60 of the defrosting device 100 as follows to suppress fogging of the window glass 5. For example, when the control device 50 determines that the temperature inside the vehicle cabin is equal to or lower than a predetermined temperature upon starting the vehicle, it operates the heater 21 of the dehumidifier 10 in a medium output mode (Mid) and the heating wire 6 of the glass heating device 60 in a high output mode (Hi) until the temperature inside the vehicle cabin reaches a threshold temperature T1. When the dehumidifier 10 and the glass heating device 60 are thus operated, the dehumidifier 10 dehumidifies the vehicle cabin, and the glass heating device 60 directly heats the window glass 5.

[0036] After that, the temperature inside the vehicle cabin gradually increases, and when the temperature inside the vehicle cabin reaches the threshold temperature T1, the control device 50 switches the operation of the heating wire 6 of the glass heating device 60 from the high output mode (Hi) to the low output mode (Lo) at that time, and after continuing the operation of the glass heating device 60 in the low output mode (Lo) for a predetermined time, stops the operation of the glass heating device 60. In other words, after the temperature inside the vehicle cabin reaches or exceeds the threshold temperature T1, the output of the glass heating device 60 is gradually reduced. At this time, the dehumidifier 10 continues to operate in the medium output mode (Mid).

[0037] As with the first embodiment, the anti-fogging device 100 of this embodiment can improve the heating efficiency of the vehicle interior in a low-temperature environment and efficiently prevent fogging of the window glass 5 while suppressing power consumption. However, in the anti-fogging device 100 of this embodiment, the output of the glass heating device 60 is gradually reduced after the temperature inside the vehicle cabin exceeds the threshold temperature T1, so that even in situations where the window glass 5 is cooled by the wind when the vehicle is traveling at high speed, the temperature of the window glass 5 is prevented from dropping suddenly and causing the window glass 5 to fogging up.

[0038] [Third embodiment] FIG. 6 is a characteristic diagram showing the changes in the room temperature, the heater power of the dehumidifier 10, and the power of the glass heating device 60 when the anti-fogging device 100 of this embodiment is used. In this embodiment, when the anti-fogging device 100 is operating in a low-temperature environment, the heater 21 of the dehumidifier 10 is used in a medium output mode (Mid) and a high output mode (Hi), and the heating wire 6 of the glass heating device 60 is used in a high output mode (Hi) and a low output mode (Lo).

[0039] When the temperature inside the vehicle cabin is below a predetermined temperature (low temperature environment), the control device 50 controls the dehumidifier 10 and the glass heating device 60 of the defrosting device 100 as follows to suppress fogging of the window glass 5. For example, when the control device 50 determines that the temperature inside the vehicle cabin is equal to or lower than a predetermined temperature upon starting the vehicle, it operates the heater 21 of the dehumidifier 10 in a medium output mode (Mid) and the heating wire 6 of the glass heating device 60 in a high output mode (Hi) until the temperature inside the vehicle cabin reaches a threshold temperature T1. When the dehumidifier 10 and the glass heating device 60 are thus operated, the dehumidifier 10 dehumidifies the vehicle cabin, and the glass heating device 60 directly heats the window glass 5.

[0040] Thereafter, when the temperature inside the vehicle cabin gradually increases and reaches the threshold temperature T1, the control device 50 switches the operation of the heating wire 6 of the glass heating device 60 from the high output mode (Hi) to the low output mode (Lo) at that time, continues operation of the glass heating device 60 in the low output mode (Lo) for a predetermined time, and then stops operation of the glass heating device 60. On the other hand, for the heater 21 of the dehumidifier 10, the control device 50 switches from the medium output mode (Mid) to the high output mode (Hi) when the temperature inside the vehicle cabin reaches the threshold temperature T1, continues operation in the high output mode (Hi) for a predetermined time, and then switches back to the medium output mode (Mid).

[0041] The antifogging device 100 of this embodiment can achieve substantially the same effects as those of the second embodiment. However, the anti-fogging device 100 of this embodiment switches the heater 21 of the dehumidifier 10 from the medium output mode (Mid) to the high output mode (Hi) at the same time that the operation of the glass heating device 60 is switched from the high output mode (Hi) to the low output mode (Lo) after the temperature inside the vehicle compartment exceeds the threshold temperature T1. This makes it possible to suppress fogging of the window glass 5 due to a drop in the temperature of the glass heating device 60 while suppressing an increase in power consumption of the entire vehicle.

[0042] [Fourth embodiment] FIG. 7 is a characteristic diagram showing the changes in the room temperature, the heater power of the dehumidifier 10, and the power of the glass heating device 60 when the anti-fogging device 100 of this embodiment is used. In this embodiment, when the anti-fogging device 100 is operating in a low-temperature environment, the heater 21 of the dehumidifier 10 is used in high-output mode (Hi) and medium-output mode (Mid), and the heating wire 6 of the glass heating device 60 is used only in high-output mode (Hi).

[0043] When the temperature inside the vehicle cabin is below a predetermined temperature (low temperature environment), the control device 50 controls the dehumidifier 10 and the glass heating device 60 of the defrosting device 100 as follows to suppress fogging of the window glass 5. The control of this embodiment is executed when the on-board battery has sufficient power. For example, when the control device 50 determines that the temperature inside the vehicle cabin is equal to or lower than a predetermined temperature, such as when the vehicle is started, the control device 50 operates the heater 21 of the dehumidifier 10 and the heating wire 6 of the glass heating device 60 in high output mode (Hi) until the temperature inside the vehicle cabin reaches the threshold temperature T1. When the dehumidifier 10 and the glass heating device 60 are thus operated, the dehumidifier 10 dehumidifies the vehicle cabin, and the glass heating device 60 directly heats the window glass 5.

[0044] Thereafter, the temperature inside the vehicle cabin gradually increases, and when the temperature inside the vehicle cabin reaches the threshold temperature T1, the control device 50 stops the operation of the heating wire 6 of the glass heating device 60 at that point, and the operation of the heater 21 of the dehumidifier 10 continues as is (in the high output mode) for a predetermined time. Then, after the predetermined time has elapsed, the control device 50 switches the operation of the heater 21 of the dehumidifier 10 from the high output mode (Hi) to the medium output mode (Mid).

[0045] The antifogging device 100 of this embodiment can obtain substantially the same basic effects as the above-described embodiments. The anti-fogging device 100 of this embodiment continues to operate the heater 21 of the dehumidifier 10 in high output mode (Hi) for a predetermined time even after the temperature inside the vehicle cabin exceeds the threshold temperature T1, but stops operation of the glass heating device 60 when the temperature inside the vehicle cabin exceeds the threshold temperature T1, thereby creating a corresponding power surplus for the vehicle. Therefore, it is possible to reliably suppress the occurrence of fogging on the window glass 5, which would otherwise occur if the temperature of the window glass 5 were to drop sharply after the temperature inside the vehicle cabin exceeds the threshold temperature T1, without incurring a significant increase in power consumption.

[0046] <Other embodiments> In each of the above-described embodiments, the control device 50 operates both the glass heating device 60 and the dehumidifier 10 until the temperature inside the vehicle interior reaches the threshold temperature, and stops the glass heating device 60 or reduces the output of the glass heating device 60 when the temperature inside the vehicle interior exceeds the threshold temperature T1. However, the switching criterion for stopping the glass heating device 60 or reducing the output of the glass heating device 60 may be the elapsed time instead of the temperature inside the vehicle interior.

[0047] That is, the control device 10 may operate both the glass heating device 60 and the dehumidifier 10, and stop the glass heating device 60 or control the output of the glass heating device 60 to reduce when a predetermined time has elapsed since the glass heating device 60 and the dehumidifier 10 started operating.

[0048] The present invention is not limited to the above-described embodiment, and various design modifications are possible without departing from the spirit of the present invention. For example, in the above embodiment, a windshield is used as an example of a window glass for removing fogging, but the window glass for suppressing fogging is not limited to a windshield, and may be a rear window, a side window, or the like. Furthermore, in the above embodiment, the dehumidifier 10 is employed in which the dehumidification operation and the regeneration operation of the two moisture adsorption devices 11A, 11B are alternately switched, but the configuration of the dehumidifier 10 is not limited to this. The dehumidifier 10 may also be configured in such a way that dehumidifying air flows through a partial area of ​​the rotating disk-shaped moisture adsorption device, and regeneration air flows through the remaining area. [Explanation of symbols]

[0049] 5...Window glass 6…Heating wire 10...Dehumidifier 15...Moisture absorption section 50...Control device 60...Glass heating device 100...Anti-fogging device

Claims

1. a desiccant-type dehumidifying device that performs a dehumidifying operation in which water vapor in the vehicle interior is adsorbed by a moisture adsorption unit, and a regenerating operation in which the moisture adsorption unit is heated to desorb the adsorbed water vapor; a glass heating device that heats the window glass with an electric heating wire; a control device for controlling the operation of the dehumidifying device and the glass heating device, When the temperature inside the vehicle cabin is below a predetermined temperature, the control device operates both the glass heating device and the dehumidifying device until the temperature inside the vehicle cabin reaches a threshold temperature, and when the temperature inside the vehicle cabin exceeds the threshold temperature, the control device stops the glass heating device or reduces the output of the glass heating device.

2. 2. The vehicle defrosting device according to claim 1, wherein the control device, when suppressing fogging of the window glass when the temperature inside the vehicle interior is below a predetermined temperature, gradually reduces the output of the glass heating device after the temperature inside the vehicle interior exceeds the threshold temperature.

3. 3. The vehicle defrosting device according to claim 2, wherein, when suppressing fogging of the window glass when the temperature inside the vehicle interior is below a predetermined temperature, the control device reduces the output of the glass heating device and increases the heating output of the dehumidifying device to the moisture absorption section after the temperature inside the vehicle interior exceeds the threshold temperature.

4. a desiccant-type dehumidifying device that performs a dehumidifying operation in which water vapor in the vehicle interior is adsorbed by a moisture adsorption unit, and a regenerating operation in which the moisture adsorption unit is heated to desorb the adsorbed water vapor; a glass heating device that heats the window glass with an electric heating wire; a control device for controlling the operation of the dehumidifying device and the glass heating device, When the temperature inside the vehicle cabin is below a predetermined temperature, the control device operates both the glass heating device and the dehumidifying device until the temperature inside the vehicle cabin reaches a threshold temperature, reduces the output of the glass heating device when the temperature inside the vehicle cabin exceeds the threshold temperature, and stops the glass heating device when a predetermined time has elapsed since the operation of the glass heating device and the dehumidifying device began.

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