JP6799760B2 - Condensation sensor, condensation detection system, and refrigerator - Google Patents

Description

The present disclosure relates to a dew condensation sensor that detects dew condensation in advance in order to prevent dew condensation, a dew condensation detection system using the same, and a refrigerator.

In recent years, the airtightness of houses has improved and it has become a comfortable place to live, but there is a problem of dew condensation on the wall surface, ceiling surface, closet, etc., and it is required to predict dew condensation in advance. ..

Further, even in a refrigerator having improved heat insulation performance, a means for preventing dew condensation on the surface of the main body of the refrigerator and the inner wall surface of the refrigerator by detecting temperature and humidity and heating the refrigerator is adopted. However, in order to improve the freshness of vegetables, if the vegetable storage case has a closed structure and is stored at high humidity, the wall surface of the case will condense and the vegetables will rot due to the influence of the condensed water.

In response to the problem of detecting such dew condensation in advance, by lowering the temperature of the device that detects dew condensation to a temperature lower than the ambient temperature, the dew point temperature of the device is lowered, and dew condensation is detected earlier than the surroundings. (See, for example, Patent Document 1).

FIG. 9 is a side view of the conventional dew condensation sensor described in Patent Document 1. In FIG. 9, the dew condensation detection unit 1 utilizes the fact that the resistance value changes when water droplets adhere between the comb-shaped electrodes. The cooling panel 3 is in close contact with the detection surface of the dew condensation detection unit 1 with good thermal conductivity, and the heating panel 4 and the heat insulating material layer 5 are in close contact with each other in this order. A dew condensation sensor is composed of these members. As a specific detection method, when dew condensation is detected, only the cooling panel 3 is cooled by a device such as a Peltier element, and the close contact portion 2a is lowered to a predetermined temperature so that the dew condensation detection unit 1 arrives faster than the surroundings. Condensate. Further, in order to quickly detect dew condensation next time, after dew condensation, only the heating panel 4 is heated by a device such as a surface heating heater to raise the close contact portion 2b to a predetermined temperature, thereby accelerating the drying of the dew condensation detection unit 1. When the dew condensation sensor is attached to the refrigerator body, a heat insulating material layer 5 is provided in order to eliminate the heat effect from the refrigerator body side. The conventional dew condensation sensor described in Patent Document 1 detects dew condensation in advance with such a configuration and operation.

However, in the conventional configuration as described above, since the dew condensation detection unit 1, the cooling panel 3, the heating panel 4, and the heat insulating material layer 5 are laminated in this order, the device becomes large and requires a large mounting space. Become. Further, a Peltier element for cooling the cooling panel 4, another device such as a surface heating heater for heating the heating panel 4, and a power supply device for driving those devices are required. Therefore, the conventional configuration as described above has a problem that the specifications are very expensive.

Further, in the conventional configuration as described above, when the dew condensation sensor is installed in the vegetable case of the refrigerator vegetable compartment, the drawer case moves back and forth, so it is necessary to expand and contract the connection harness between the dew condensation sensor and the main body side. is there. Therefore, the conventional configuration as described above has a problem that the operability, reliability, serviceability, and the like are inferior.

Japanese Unexamined Patent Publication No. 4-544444

The present disclosure has been made in view of the above problems, and provides a low-cost dew condensation sensor that can be miniaturized and thinned and can be installed in a space-saving manner without the need for additional devices and power supply devices. Further, the present disclosure provides a refrigerator having specifications that do not require the connection harness to be moved even when the dew condensation sensor is installed in the vegetable case of the refrigerator.

Specifically, the dew condensation sensor according to the example of the present disclosure includes a wiring board provided with a conductor circuit pattern, a dew condensation detection element connected to the conductor circuit pattern on the wiring board, and a heat generating component provided on the wiring board. And. The surface of the wiring board opposite to the surface on which the dew condensation detection element is mounted is cooled so that the dew condensation detection element is cooled below the ambient temperature.

With such a configuration, main components including a conductor circuit pattern, a dew condensation detecting element, and a heat generating component are mounted on one wiring board, and a sensor for pre-detecting dew condensation can be obtained. Further, with such a configuration, the dew condensation sensor can be made thinner and smaller, and the mounting space for the dew condensation sensor can be reduced. Further, with such a configuration, a thin and miniaturized dew condensation sensor can be obtained, so that the degree of freedom in mounting the dew condensation sensor is widened, and the choice of installation location is increased. Further, since the dew condensation sensor obtained by such a configuration has a simple configuration, the assembly man-hours can be reduced and the cost can be reduced. Further, since the assembly can be automated by such a configuration, the existing printed wiring board mounting process can be utilized, and the cost can be reduced by reducing the man-hours.

The present disclosure also provides a refrigerator including a dew condensation sensor configured by any of the above configurations, a cooling member for cooling the dew condensation sensor, and a storage chamber provided with the dew condensation sensor. In the refrigerator according to the example of the present disclosure, the dew condensation sensor has a wiring board and a dew condensation detecting element provided on the wiring board. The cooling member is configured to cool the surface of the wiring board on which the dew condensation detection element of the dew condensation sensor is mounted, which is opposite to the surface on which the dew condensation detection element is provided. The condensation sensor is installed inside a substantially enclosed storage room (vegetable room, etc.). The cooling member is configured to cool the surface of the wiring board of the dew condensation sensor opposite to the surface on which the dew condensation detection element is provided by utilizing the circulating cold air in the refrigerator.

With such a configuration, dew condensation can be detected in advance in a movable vegetable case, such as a storage case in a drawer-type storage room that is pulled out back and forth, and vegetables can be stored in a high humidity state without dew condensation. become. Further, with such a configuration, it is not necessary to newly install a cooling device for detecting dew condensation, and since the existing circulating cold air in the refrigerator is used, it is possible to detect dew condensation in the vegetable case in advance with an easy configuration. Further, with such a configuration, vegetables can be kept fresh in a high humidity state up to the dew condensation limit.

Further, in the dew condensation sensor according to the example of the present disclosure, the dew condensation detecting element may have a moisture-sensitive portion formed of a mixture of a hygroscopic resin and a conductor powder. With such a configuration, the moisture-sensitive portion of the dew condensation detection element can be treated as a paste-like material. Therefore, the degree of freedom of the processing method for forming the moisture-sensitive portion of the dew condensation detection element, such as printing and coating, is expanded. If the moisture-sensitive portion of the dew condensation detection element has a surface-mounted component shape, it can be mounted on one wiring board with the same device as other discrete components.

Further, in the dew condensation sensor according to the example of the present disclosure, the heat generating component may be composed of a surface mount resistor. With such a configuration, there is no need for large-scale parts such as a surface heating heater, so by mounting a simple component on the wiring board, the recovery time until the next dew condensation detection (the dew condensation sensor becomes dry and the temperature of the dew condensation detection element is high. It is possible to shorten the time until it cools down.

Further, in the dew condensation sensor according to the example of the present disclosure, the heat generating component may be mounted on the same surface of the wiring board on which the dew condensation detection element is mounted. With such a configuration, the heat from the heat generating component is transferred to the dew condensation detection element only on the surface of the wiring board, and very efficient heat conduction becomes possible.

Further, in the dew condensation sensor according to the example of the present disclosure, a heat generating component may be arranged in the vicinity of the conductor circuit pattern connected to the dew condensation detection element. With such a configuration, heat is transferred by utilizing a metal pattern having a very high thermal conductivity, so that the dew condensation detection element can be heated more efficiently.

Further, the dew condensation detection system according to the example of the present disclosure includes a dew condensation sensor having any of the above configurations. Further, in the dew condensation detection system according to the example of the present disclosure, the dew condensation sensor is configured to determine that dew condensation has occurred after the lapse of the first specified time from the time when the dew condensation detection element detects the occurrence of dew condensation. May be good. Due to such a configuration, after a slight change between the dew condensation state and the dry state (whether it is the dry state or the state before it, whether the state is such that a very small amount of dew condensation remains, dry / dew condensation). Since the dew condensation determination is performed in a stable state (after a state in which the determination of the detection of dew may fluctuate), it is possible to detect dew condensation with high accuracy in advance.

Further, the dew condensation detection system according to the example of the present disclosure may be configured so that the heat generation of the heat generating component ends after the lapse of the second specified time from the time when the dew condensation detection element detects the dry state. With such a configuration, it is possible to determine the detection of dryness / condensation, which is a subtle fluctuation (whether it is in a dry state, a state in front of it, or a state in which a very small amount of condensation remains) that begins to recover from condensation. It is possible to avoid the end of heat generation in a state where there is a possibility of shaking). Therefore, it is possible to prepare for the timing of the next dew condensation detection while the dew condensation detection element is surely dried.

Further, the dew condensation detection system according to the example of the present disclosure may be configured such that the dew condensation detection element performs dew condensation detection next time after the lapse of a third specified time after the end of heat generation. With such a configuration, the temperature of the dew condensation detection element cools and returns to the same temperature as the previous detection timing, so that it is possible to eliminate erroneous detection of dew condensation determination due to the dew point temperature difference.

The refrigerator according to an example of the present disclosure includes a dew condensation detection system having a dew condensation sensor configured with any of the above configurations. Such a configuration eliminates the need for another cooling means such as a Peltier element. Therefore, with such a configuration, it is possible to save space in the place where the dew condensation sensor is installed. Further, with such a configuration, a high output power supply is not required, and dew condensation can be detected in advance at low cost. In addition, such a configuration enables high humidity storage of vegetables by substantially sealing the vegetable case.

FIG. 1 is a plan view of the dew condensation sensor according to the first embodiment of the present disclosure as viewed from above. FIG. 2 is a side view of the dew condensation sensor according to the first embodiment of the present disclosure. FIG. 3 is an enlarged plan view of a main part of the dew condensation sensor according to the first embodiment of the present disclosure as viewed from above. FIG. 4 is a diagram showing the relationship between the dew point due to the temperature and humidity of the dew condensation sensor according to the first embodiment of the present disclosure and the sensor output. FIG. 5 is a control flowchart of a heat generating component of the dew condensation sensor according to the first embodiment of the present disclosure. FIG. 6 is a vertical cross-sectional view of the refrigerator using the dew condensation sensor according to the second embodiment of the present disclosure. FIG. 7 is a vertical cross-sectional view of the vegetable compartment of the refrigerator using the dew condensation sensor according to the second embodiment of the present disclosure. FIG. 8 is an enlarged vertical sectional view of a main part of the vegetable compartment of the refrigerator using the dew condensation sensor according to the second embodiment of the present disclosure. FIG. 9 is a side view of the conventional dew condensation sensor.

Hereinafter, examples of the embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiments.

(Embodiment 1)
FIG. 1 is a plan view of the dew condensation sensor according to the first embodiment of the present disclosure as viewed from above. FIG. 2 is a side view of the dew condensation sensor according to the first embodiment of the present disclosure. FIG. 3 is an enlarged plan view of a main part of the dew condensation sensor according to the first embodiment of the present disclosure as viewed from above. FIG. 4 is a diagram showing the relationship between the dew point due to the temperature and humidity of the dew condensation sensor according to the first embodiment of the present disclosure and the sensor output. FIG. 5 is a diagram showing a control flowchart of a heat generating component of the dew condensation sensor according to the first embodiment of the present disclosure.

As shown in FIGS. 1 to 3, the dew condensation sensor 18 includes a dew condensation detection element 11, a wiring board 12, a heat generating component 13, a plurality of electronic components 14, a detection circuit unit 15, and an external connection unit 16. It is composed of a conductor pattern 17. The dew condensation detection element 11 is mounted on one surface of the wiring board 12, and a detection circuit unit 15 composed of a heat generating component 13 and a plurality of electronic components 14 is mounted on the same surface. As shown in FIG. 2, the dew condensation detecting element 11 is electrically connected to the external connecting portion 16 by the conductor pattern 17. Further, as shown in FIG. 2, the surface of the wiring board 12 opposite to the surface on which the dew condensation detection element 11 is mounted has no mounting parts and is configured as a cooling surface. The surface of the wiring board 12 opposite to the surface on which the dew condensation detection element 11 is mounted is configured such that the dew condensation detection element 11 is cooled via the wiring board 12 by cooling from a cooling source. As the wiring board 12, a material such as paper phenol, composite, or glass epoxy is used, and the plate thickness is generally 1.6 mm. As the wiring board 12, a thin base material may be used in order to improve the cooling efficiency from the cooling source, or a processed product of an insulating and highly thermally conductive resin material having a high thermoelectricity may be used. ..

As the dew condensation detecting element 11, a device having a large change in physical quantity between a dry state without water adhesion and a dew condensation state with water adhered is preferable. For example, in the present embodiment, as the dew condensation detecting element 11, a mixture of a hygroscopic resin such as polyamide and a conductor powder such as carbon is used. In general, the resin used for the capacitive humidity sensor alone has poor accuracy at a high humidity of 90% RH or more, and it is impossible to distinguish between high humidity and dew condensation. In this regard, by using the mixture of the present disclosure, the hygroscopic resin swells very much at the time of dew condensation, and the contact rate between the conductors can be made very small, so that the resistance value changes between the time of drying and the time of dew condensation. It can be changed greatly. For example, normally, the resistance value of several kΩ in a dry state becomes as high as several hundred kΩ when dew condensation occurs, and it can be regarded as a change amount of 100 times or more. Further, the mixture of the present disclosure can be processed into a paste-like material, and can be directly printed and molded between the conductor circuit patterns 17 on the wiring board 12. Alternatively, if a mixture is formed between the base substrates of the electrodes at both ends as in a general surface-mounted resistor type, the dew condensation detection element 11 can be processed as a component that can be mounted by existing equipment.

As the heat-generating component 13, if a general surface-mounted resistor is diverted, it can be easily realized by self-heating when energized, and the desired resistance value may be set within the allowable power in consideration of the safety factor. .. Alternatively, the heat generating component 13 may be directly printed and molded between the conductor patterns by printing a silver pattern having a low resistance value. Further, the heat generating component 13 heats the dew condensation detecting element 11, and it is preferable that the distance between the heat generating component 13 and the dew condensation detecting element 11 is as short as possible. Specifically, as shown in FIG. 3, the conductor patterns 17a and 17b to which the dew condensation detection element 11 is connected are made as large as possible, and the distance D between the conductor patterns 17a and 17b and the heat generating component 13 is legally set. It is desirable to be designed to ensure the minimum regulated distance. Further, since the conductor patterns 17c and 17d to which the heat generating component 13 is connected are heated by the heat generated by the heat generating component 13, the efficiency of heat conduction can be further improved by shortening the distance from the conductor patterns 17a and 17b. ..

The operation and operation of the dew condensation detection system using the dew condensation sensor 18 configured as described above will be described below with reference to FIGS. 4 and 5.

First, the operation in which the dew condensation sensor 18 can detect dew condensation in advance will be described. In FIG. 4, the ambient temperature t2 where the dew condensation sensor 18 is installed is set to 10 ° C. for the sake of clarity. At this time, since there is no cooling from the cooling source, the temperature of the dew condensation detection element 11 is also 10 ° C. indicated by the dotted line, and dew condensation starts when the relative humidity rises to 100% RH (time T2). That is, the dew point temperature is 10 ° C. When the time T2 is reached, the dew condensation sensor 18 determines that dew condensation has occurred, and changes the output voltage from V1 at the time of drying to V2 as shown by the dotted line in FIG.

Next, when the wiring substrate 12 is cooled by the cooling source and the temperature t1 of the dew condensation detection element 11 is set to 8 ° C., which is 2 ° C. lower than the ambient environment temperature 10 ° C., the temperature t1 of the dew condensation detection element 11 is FIG. It becomes like the solid line of. Then, when the relative humidity rises to 90% RH (time T1), dew condensation begins. That is, the dew point temperature is 8 ° C., and dew condensation occurs when the relative humidity reaches 90% RH. When the time T1 is reached, the dew condensation sensor 18 determines that dew condensation has occurred, and changes the output voltage from V1 at the time of drying to V2 as shown by the solid line in FIG.

To summarize the above, if the dew condensation sensor 18 is installed in an environment with an ambient environment temperature of 10 ° C. and the dew condensation detection element 11 is cooled to 8 ° C., the dew condensation sensor 18 is formed even if the relative humidity is 90% RH without dew condensation. Will determine that condensation has occurred. That is, dew condensation can be detected at a time T1 earlier than the time T2 shown in FIG. In the above explanation, the temperature of the dew condensation detection element 11 is set to 8 ° C. for the determination at a relative humidity of 90% RH, but in the case of a slightly higher humidity side, the cooling setting may be higher than 8 ° C. On the low humidity side, the cooling setting may be lower.

Next, the control of the dew condensation detection system when the dew condensation sensor 18 is installed at the detection location will be described with reference to FIG. 5, specifically in combination with the function of the heat generating component 13. Unless otherwise specified, the control described below is performed by the control unit (not shown) of the dew condensation detection system.

First, in step S1, the dew condensation sensor 18 determines whether or not dew condensation is detected. If the output voltage of the dew condensation sensor 18 is V2 as shown in FIG. 4 for dew condensation detection (prediction timing), the logic proceeds to step S2. Instead, if the output voltage of the dew condensation sensor 18 remains V1, the state of step S1 is continued.

In step S2, the first timer is started, and it is determined whether or not the specified A time has elapsed. If the specified A time has passed, the logic proceeds to step S3, and it is determined that condensation has occurred. If not, the logic is returned to step S1. Next, in step S3, it is determined that dew condensation has occurred, and in step S4, dehumidification and space opening are performed from the refrigerator body side to the installation location of the dew condensation sensor 18. When finished, the logic proceeds to step S5.

In step S5, in order to completely remove and dry the moisture that may have adhered to the dew condensation detection element 11, the heating component 13 is allowed to be energized and the logic proceeds to step S6. In step S6, it is determined whether or not the output voltage of the dew condensation sensor 18 is V1. If the output voltage of the dew condensation sensor 18 is V1, it is determined that the dew condensation sensor 18 has returned (dried), and the logic proceeds to step S7. Instead, if the output voltage of the dew condensation sensor 18 remains V2, the heat generating component 13 continues the state of step S6 while being energized.

Next, in step S7, the second timer is started, and it is determined whether or not the specified B time has elapsed. If the specified B time has elapsed, assuming that the water has been completely removed, the logic proceeds to step S8, and the energization of the heat generating component 13 is terminated. If not, the logic is returned to step S6. Finally, in step S9, the third timer is started, and it is determined whether or not the predetermined C time has elapsed. If the specified C time has elapsed, the dew condensation detection element 11 determines that the temperature has returned to the initial temperature, and returns the logic to step S1. If not, the state of step S9 is continued.

As described above, in the present embodiment, the wiring board 12 provided with the conductor pattern 17, the dew condensation detecting element 11 connected to the conductor patterns 17a and 17b of the wiring board 12, and the heat generating component 13 are one. It is mounted on a number of wiring boards 12. Further, in the present embodiment, the surface of the wiring board 12 opposite to the surface on which the dew condensation detection element 11 is mounted is cooled, and the dew condensation detection element 11 is cooled below the ambient temperature. With such a configuration, a plurality of components are not required, and dew condensation can be detected in advance with a simple component on one wiring board 12. Therefore, with such a configuration, the dew condensation sensor 18 can be miniaturized, and the mounting space for the dew condensation sensor 18 can be minimized. As a result, the degree of freedom in the installation location of the dew condensation sensor 18 on the refrigerator body side can be increased.

Further, the moisture-sensitive portion of the dew condensation detecting element 11 is formed of a mixture of a moisture-absorbing resin and a conductor powder. With such a configuration, the moisture-sensitive portion of the dew condensation detection element 11 can be treated as a paste-like material, and its viscosity can be easily adjusted. Therefore, with such a configuration, the degree of freedom of the processing method for forming the moisture-sensitive portion of the dew condensation detecting element 11 such as printing and coating is expanded. Further, if the moisture-sensitive portion of the dew condensation detection element 11 has a surface-mounted component shape, it can be mounted on one wiring board 12 with the same device as other discrete components, and is the same as the conductor pattern 17. If it is formed by a construction method, the manufacturing man-hours can be significantly reduced.

Further, since the heat generating component 13 is a surface-mounted resistor, there is no need for a large-scale component such as a surface heating heater. Therefore, by mounting a simple component on the wiring board 12, the recovery time until the next dew condensation detection is performed. Can be shortened, and the degree of freedom in designing the refrigerator body can be expanded. Similar to the conductor pattern 17, the heat generating component 13 can also be used as a printing resistor on the wiring board 12. In this case, the manufacturing man-hours can be further reduced.

Further, since the heat generating component 13 is mounted on the same surface of the wiring board 12 on which the dew condensation detection element 11 is mounted, the heat from the heat generating component 13 is transferred to the dew condensation detection element 11 only on the surface of the wiring board 12. It is transmitted. Therefore, with such a configuration, very efficient heat conduction becomes possible, and the drying recovery time of the dew condensation detecting element 11 can be further shortened.

Further, the heat generating component 13 is arranged in the vicinity of the conductor patterns 17a and 17b connected to the dew condensation detecting element 11. With such a configuration, heat is transferred by utilizing a metal pattern having a very high thermal conductivity, so that the dew condensation detection element 11 can be heated more efficiently.

Further, the timing at which the dew condensation sensor 18 determines that dew condensation has occurred is set to be after a predetermined A time has elapsed from the time when the dew condensation detecting element 11 detects the dew condensation. With such a configuration, the dew condensation is determined in a stable state after a slight fluctuation between dew condensation and drying, so that accurate dew condensation can be predicted in advance.

Further, the timing for ending the heat generation of the heat generating component 13 is set to be after a predetermined B time has elapsed from the time when the dew condensation detecting element 11 detects the dry state. With such a configuration, it is possible to avoid the end of heat generation due to a subtle fluctuation that starts to recover from the dew condensation state, so that the dew condensation detection element 11 can be surely prepared for the next dew condensation detection timing in a dry state. ..

Further, the timing at which the dew condensation detection element 11 next detects dew condensation after the heat generation of the heat generating component 13 is completed is set to be after a predetermined C time has elapsed from the end of the heat generation. With such a configuration, the temperature of the dew condensation detection element 11 cools and returns to the same temperature as the previous detection timing, so that it is possible to eliminate erroneous detection of dew condensation determination due to the dew point temperature difference.

Although the heat-generating component 13 is used in the present embodiment, the heat-generating component 13 may be abolished as long as it can be applied within the dew condensation recovery time by natural drying or air drying on the refrigerator body side. Further, in the present embodiment, the mode of cooling the dew condensation detection element 11 has been described, but if there is a distribution difference in the surrounding environment in the range applicable to the refrigerator body, the dew condensation sensor is located in the highest humidity part or the lowest temperature part. If 18 is installed, the portion starts to condense early in time, so that dew condensation can be detected in advance without cooling.

(Embodiment 2)
FIG. 6 is a vertical sectional view of a refrigerator provided with the dew condensation detection system according to the second embodiment of the present disclosure. FIG. 7 is a vertical cross-sectional view of the vegetable compartment of the refrigerator provided with the dew condensation detection system according to the second embodiment of the present disclosure. FIG. 8 is an enlarged vertical sectional view of a main part of the vegetable compartment of the refrigerator provided with the dew condensation detection system according to the second embodiment of the present disclosure.

In the second embodiment of the present disclosure, the refrigerator provided with the dew condensation detection system of the first embodiment will be described. In FIGS. 6 to 8, the refrigerator 100 of the present embodiment includes a heat insulating box 101. The heat insulating box 101 is filled and foamed in the space between the outer box 102 mainly using a steel plate, the inner box 103 molded with a resin such as ABS, and the outer box 102 and the inner box 103, for example, hard. It consists of a foamed heat insulating material such as urethane foam. The heat insulating box 101 is insulated from the surrounding atmosphere, and the inside is divided into a plurality of storage chambers.

A refrigerating chamber 104 as a first storage chamber is provided at the uppermost portion of the heat insulating box 101. Below the refrigerating chamber 104, a switching chamber 105 as a fourth storage chamber and an ice making chamber 106 as a fifth storage chamber are provided side by side. Below the switching chamber 105 and the ice making chamber 106, a vegetable chamber 107 as a second storage chamber is provided. A freezing chamber 108 as a third storage chamber is arranged at the lowermost part of the heat insulating box 101.

The refrigerating chamber 104 is usually set to 1 ° C. to 5 ° C. with a lower limit of a temperature at which it does not freeze for refrigerated storage. The vegetable compartment 107 is set to a temperature of 2 ° C. to 7 ° C., which is equal to or slightly higher than that of the refrigerator compartment 104. The freezing chamber 108 is set in the freezing temperature zone, and is usually set at −22 ° C. to −15 ° C. for frozen storage. In addition, in order to improve the frozen storage state, it may be set at a low temperature of, for example, −30 ° C. or −25 ° C. The switching chamber 105 includes a refrigerating temperature range set at 1 ° C to 5 ° C, a vegetable temperature range set at 2 ° C to 7 ° C, and a freezing temperature range usually set at -22 ° C to -15 ° C. , It is possible to switch to a preset temperature zone between the refrigerating temperature zone and the freezing temperature zone. The switching chamber 105 is a storage chamber provided with an independent door arranged side by side in the ice making chamber 106, and is often provided with a drawer type door.

In the present embodiment, the switching chamber 105 is a storage chamber set to a temperature zone including the refrigerating temperature zone and the freezing temperature zone, but refrigeration is entrusted to the refrigerating chamber 104 and the vegetable compartment 107, and freezing is performed. The storage chamber may be left to the freezing chamber 108 to specialize in switching only the above temperature zone between refrigeration and freezing. Further, the switching chamber 105 may be a storage chamber fixed in a specific temperature zone.

The ice making chamber 106 uses water sent from a water storage tank (not shown) in the refrigerating chamber 104 to make ice with an automatic ice making machine (not shown) provided in the upper part of the ice making chamber. Ice is stored in an ice storage container (not shown) located at the bottom of the ice making chamber.

As shown in FIG. 6, the top surface portion of the heat insulating box body 101 has a shape in which a recess is provided in a stepped manner toward the back surface of the refrigerator 100. A machine room 101a is formed in a stepped recess. The machine room 101a houses high-pressure side components of the refrigeration cycle, such as a compressor 109 and a dryer (not shown) for removing water. That is, the machine room 101a in which the compressor 109 is arranged is formed so as to bite into the uppermost rear region in the refrigerating room 104.

The feature described below in the present embodiment is a type in which a machine room is provided in the lowermost storage chamber rear region of the heat insulating box 101 and the compressor 109 is arranged therein. It may be applied to a refrigerator. Further, the refrigerator 100 may be a refrigerator having a so-called mid-freezer structure in which the arrangements of the freezing chamber 108 and the vegetable compartment 107 are interchanged.

Next, as shown in FIG. 6, a cooling chamber 110 for generating cold air is provided on the back surface of the vegetable compartment 107 and the freezing chamber 108. Between the vegetable compartment 107 and the cooling chamber 110, and between the freezing chamber 108 and the cooling chamber 110, there is an air passage 141 for transporting cold air to each chamber having heat insulating properties, and a heat insulating partition from each chamber. The back surface partition walls 111 configured in the above are provided respectively.

A cooler 112 is arranged in the cooling chamber 110. In the upper space of the cooler 112, a cooling fan 113 that blows the cold air cooled by the cooler 112 by the forced convection method to the refrigerator chamber 104, the switching chamber 105, the ice making chamber 106, the vegetable chamber 107, and the freezer chamber 108 is arranged. ing. In the space below the cooler 112, a radiant heater 114 made of a glass tube for defrosting frost and ice adhering to the cooler 112 and its surroundings during cooling is provided. Further below, a drain pan 115 for receiving the defrost water generated during defrosting and a drain tube 116 penetrating from the deepest part of the drain pan 115 to the outside of the refrigerator are provided. An evaporating dish 117 is provided outside the refrigerator on the downstream side of the drain tube 116.

As shown in FIGS. 6 and 7, in the vegetable compartment 107, the lower storage container 119 mounted on the frame attached to the drawer door 118 of the vegetable compartment 107 and the lower storage container 119 were placed on the lower storage container 119. The upper storage container 120 is arranged. With the drawer door 118 closed, a lid 122 mainly for substantially sealing the upper storage container 120 is held by the first partition wall 123 and the inner box 103 provided in the upper part of the vegetable compartment 107. There is. With the drawer door 118 closed, the lid 122 and the left side, the right side, and the back side of the upper surface of the upper storage container 120 are in close contact with each other, and the front side of the upper surface of the upper storage container 120 is substantially in close contact with each other. Further, the boundary between the left and right sides of the back surface of the upper storage container 120 and the lower storage container 119 has a gap so that the moisture of the storage portion 121 of the lower storage container 119 does not escape within a range where the upper storage container 120 can move and does not come into contact with each other. Is packed.

Between the lid 122 and the first partition wall 123, an air passage for cold air discharged from the discharge port 124 for the vegetable compartment 107 configured in the back surface partition wall 111 is provided. Further, a cooling member 200 penetrates and is embedded in the back surface partition wall 111 near the vegetable compartment 107. One end of the cooling member 200 is exposed in the transport air passage 141, and the dew condensation sensor 18 is mounted on the other end and arranged on the back surface partition wall 111.

Further, a space is also provided between the lower storage container 119 and the second partition wall 125 under the lower storage container 119, and a cold air passage is formed. At the lower part of the back partition wall 111 provided on the back side of the vegetable compartment 107, the suction port 126 for the vegetable compartment 107 for cooling the inside of the vegetable compartment 107 and returning the heat-exchanged cold air to the cooler 112. Is provided.

The back surface partition wall 111 is composed of a heat insulating material made of styrofoam or the like for separating the surface made of resin such as ABS from the transport air passage 141 and the cooling chamber 110 and ensuring heat insulating properties. ing.

Next, the configuration near the dew condensation sensor 18 will be described in a little more detail.

The cooling member 200 having one end exposed in the transport air passage 141 penetrates the heat-insulating back surface partition wall 111, and the dew condensation sensor 18 described in the first embodiment is thermally adhered and fixed to the other end. Has been done. Specifically, the cooling member 200 is fixed to the surface of the wiring substrate 12 of the dew condensation sensor 18 on which no component is mounted, for example, via a heat-dissipating silicon sheet or a high thermal conductive resin material that absorbs shock. It is further preferable that the cooling member 200 is physically fixed by screwing or the like together with a heat-dissipating silicon sheet or a high thermal conductive resin material that absorbs shock. As the cooling member 200, a material having extremely high thermal conductivity is preferable, and a metal such as aluminum or a molded product of high thermal conductive resin is preferable.

Further, as shown in FIG. 8, a sensor insertion port member 202 having a dimension R larger than the outer shape of the dew condensation sensor 18 is attached to a portion of the lower storage container 119 that comes into contact with the dew condensation sensor 18. The portion of the lower storage container 119 that comes into contact with the dew condensation sensor 18 is configured so that the dew condensation sensor 18 is installed inside the lower storage container 119 when the drawer door 118 is closed. As the sensor insertion port member 202, a rubber grommet or the like having a radial slit is used. If it is made of such a material, the impact mitigation between the dew condensation sensor 18 and the sensor insertion port member 202 when the dew condensation sensor 18 is inserted can be realized, and the airtightness after insertion can also be realized.

Further, as shown in FIG. 7, a humidity control mechanism 201 is mounted on the back surface of the lower storage container 119 on the back side. The humidity control mechanism 201 seals and opens the space in the vegetable compartment 107 based on the detection information of the dew condensation sensor 18 in the vegetable compartment 107. The humidity control mechanism 201 includes flap opening and closing by an electromagnet (for example, an electromagnet is provided on the refrigerator body side and a magnetic flap is provided on the lower storage container 119 side), and an electric damper drive by non-contact power supply (1 on the refrigerator body side). The drawer door 118 can be opened and closed by using the secondary side power supply (the secondary side power receiving and the motor are provided on the lower storage container 119 side) or the lower storage container 119 side insertion into the flap mechanism on the refrigerator body side. Can be operated without a harness.

The operation and operation of the refrigerator 100 configured as described above will be described below.

First, the operation of the refrigeration cycle will be described. The refrigeration cycle is operated by a signal from the control board (not shown) according to the set temperature in the refrigerator, and the cooling operation is performed. The high-temperature and high-pressure refrigerant discharged by the operation of the compressor 109 is condensed to some extent by a condenser (not shown), and further, the refrigerant pipes (not shown) are arranged on the side and back of the refrigerator 100 and the front frontage of the refrigerator 100. Through (not shown) or the like, the refrigerator 100 is condensed and liquefied while preventing dew condensation, and reaches a capillary tube (not shown). After that, in the capillary tube, the refrigerant is depressurized while exchanging heat with the suction pipe (not shown) to the compressor 109, becomes a low-temperature low-pressure liquid refrigerant, and reaches the cooler 112.

Here, the low-temperature low-pressure liquid refrigerant is heat-exchanged with the air transported from each storage chamber by the operation of the cooling fan 113 in the transport air passage 141 of the freezing chamber 108, and evaporates and vaporizes in the cooler 112. At this time, cold air for cooling each storage chamber is generated in the cooling chamber 110.

The low-temperature cold air generated in the cooling chamber 110 is separated from the cooling fan 113 into the refrigerating chamber 104, the switching chamber 105, the ice making chamber 106, the vegetable compartment 107, and the freezing chamber 108 by using the air passage and the damper 145. Cool each room to the target temperature range.

In the refrigerating chamber 104, the amount of cold air is adjusted by the damper 145 by a temperature sensor (not shown) provided in the refrigerating chamber 104, and the refrigerating chamber 104 is cooled to a target temperature. The vegetable compartment 107 is adjusted to a temperature of 2 ° C. to 7 ° C. by turning on / off the distribution of cold air and the operation of the heating unit (not shown).

In the vegetable compartment 107, a part of the cold air after cooling the refrigerating chamber 104 is configured in the middle of the return air passage of the refrigerating chamber for circulating the cold air after cooling the refrigerating chamber 104 to the cooler 112. , Is discharged from the discharge port 124 for the vegetable compartment 107. The cold air discharged from the discharge port 124 flows to the outer periphery of the upper storage container 120 and the lower storage container 119 to indirectly cool the upper storage container 120 and the lower storage container 119, and then the suction port 126 for the vegetable compartment 107. Then, it returns to the cooler 112 again.

In this way, the vegetable compartment 107 is set to the optimum temperature for the vegetables. On the other hand, cooling also has a dehumidifying effect, so that the evaporation of water from the vegetables is inevitably accelerated over time, and the weight of the vegetables is reduced. In particular, leafy vegetables wither and their commercial value deteriorates. By making the lower storage container 119 and the upper storage container 120 a substantially sealed structure, the inside of each container is kept at high humidity. However, if the sealed state is continued, dew condensation occurs in the lower storage container 119 and the upper storage container 120 due to the evaporation of water from the vegetables, and if the condensed water collects on the bottom surface of each container, the vegetables may rot. Therefore, the refrigerator 100 of the present embodiment is configured to appropriately control the humidity in the lower storage container 119, in which vegetables are often stored, by using the dew condensation sensor 18 and the humidity control mechanism 201. With such a configuration, it is possible to maintain a high humidity state without dew condensation.

Next, the operation of detecting dew condensation in advance will be described. The cooling member 200 whose one end is exposed in the transport air passage 141 is cooled by cold air, and the back surface of the wiring board 12 of the dew condensation sensor 18 is cooled by heat conduction. When the back surface of the wiring board 12 of the dew condensation sensor 18 is cooled by the cooling member 200, the dew condensation detection element 11 in the dew condensation sensor 18 is also cooled, and the dew condensation detection element 11 becomes lower than the ambient temperature of the lower storage container 119. Become. Therefore, when the lower storage container 119 changes to high humidity, the dew condensation detection element 11 is lower in temperature and the dew point temperature than the inner wall of the lower storage container 119, so that it is faster than the inner wall of the lower storage container 119 (in advance). ) Can detect dew condensation. As a specific example, when the inside of the vegetable compartment 107 is set to 5 ° C. and the relative humidity of 90% RH is detected, the temperature of the dew condensation detecting element 11 may be set to 3 ° C. Structural adjustments such as the volume of the cooling member 200, the exposed length in the transport air passage 141, and the contact thermal conductivity between the cooling member 200 and the dew condensation sensor 18, and the cooling time of the cooling member 200 (cooling fan 113 operation). It is possible to correspond to the desired dew point temperature by controlling the time) and the detection timing of the dew condensation sensor 18 from the start of cooling.

When dew condensation is detected in advance, the operation of the humidity control mechanism 201 is started, and the inside of the lower storage container 119 is lowered by opening with an opening / closing flap or dehumidifying with an electrolysis type dehumidifying element such as a solid polymer electrolyte membrane. .. After that, when the dew condensation sensor 18 returns (drys), the operation of the humidity control mechanism 201 is stopped, the inside of the lower storage container 119 is returned to a substantially sealed structure, and the inside of the lower storage container 119 is returned to a high humidity state. ..

Further, in the description of the present embodiment, the lower storage container 119 has been described, but the present embodiment may be applied to the upper storage container 120. Further, the present invention is not limited to the vegetable compartment 107, and even when the refrigerator 100 is provided with a high humidity dedicated chamber, it can be applied by applying the same concept of configuration and operation.

As described above, in the present embodiment, the opposite surface of the dew condensation sensor 18 and the wiring board 12 on which the dew condensation detection element 11 is mounted is cooled by using the dew condensation sensor 18 and the circulating cold air in the refrigerator 100. A cooling member 200 is provided, and the dew condensation sensor 18 is inserted into a substantially sealed vegetable compartment 107. With such a configuration, it is possible to divert the conventional circulating cold air and detect dew condensation in advance with almost no influence on the efficiency in terms of heat capacity. Therefore, such a configuration eliminates the need for a new device for cooling the dew condensation sensor 18. Further, with such a configuration, in cooperation with the humidity control mechanism 201, it is possible to maintain a high humidity state up to the dew condensation limit, and it is possible to improve the freshness retention of vegetables.

In the present embodiment, the cooling member 200 as the cooling source of the dew condensation sensor 18 has been described with one end exposed in the transport air passage 141, but the refrigerator 100 of the present embodiment has the vegetable compartment 107. It may be configured as a so-called mid-freezer having a freezing chamber 108 above the. In this case, the refrigerator 100 of the present embodiment is provided with a recess on the vegetable compartment 107 side of the heat insulating wall that separates the vegetable compartment 107 and the freezing chamber 108, and the cooling member 200 is arranged in the recess, and is located above the vegetable compartment 107. The cold heat of the freezing chamber 108 may be used as a cooling source for the arranged dew condensation sensor.

Further, the refrigerator 100 of the present embodiment may have a communication hole provided on the side surface or the top surface of the lower storage container 119 or the upper storage container 120 having a substantially sealed structure. In this case, in the refrigerator 100 of the present embodiment, the dew condensation sensor 18 is arranged in the communication hole, and as a cooling source of the dew condensation sensor 18, cold air for cooling the outer periphery of the lower storage container 119 or the upper storage container 120 of the vegetable compartment 107 is used. It may be configured to be used.

As described above, the present disclosure provides a dew condensation sensor capable of detecting dew condensation in advance without being composed of a plurality of complicated parts, and a dew condensation detection system and a refrigerator using the same. Therefore, it can be applied not only to household and commercial refrigerators, vegetable storages, etc., but also to distribution storages and warehouses that require high-humidity storage including foods other than vegetables.

11 Condensation detection element 12 Wiring board 13 Heat generation parts 14 Electronic parts 15 Detection circuit part 16 External connection parts 17, 17a, 17b, 17c, 17d Conductor pattern 18 Condensation sensor 100 Refrigerator 101 Insulation box 102 Outer box 103 Inner box 104 Refrigerator 105 Switching room 106 Ice making room 107 Vegetable room (storage room)
108 Freezer room 109 Compressor 110 Cooling room 111 Back partition wall 112 Cooler 113 Cooling fan 114 Radiant heater 115 Drain pan 116 Drain tube 117 Evaporating dish 118 Drawer door 119 Lower storage container 120 Upper storage container 121 Storage part 122 Lid 123 One partition wall 124 Discharge port 125 Second partition wall 126 Suction port 141 Transport air passage 200 Cooling member 201 Humidity control mechanism 202 Sensor insertion port member

Claims (9)

A wiring board with a conductor circuit pattern mounted on it,
A dew condensation detection element connected to the conductor circuit pattern on the wiring board,
It is provided with a heat generating component provided on the wiring board.
The surface of the wiring board opposite to the surface on which the dew condensation detection element is mounted is cooled.
A dew condensation sensor configured so that the dew condensation detection element is cooled below the ambient temperature. The dew condensation sensor according to claim 1, wherein the dew condensation detecting element is a moisture-sensitive portion formed of a mixture of a hygroscopic resin and a conductor powder. The dew condensation sensor according to claim 1 or 2, wherein the heat generating component is composed of a surface mount resistor. The dew condensation sensor according to any one of claims 1 to 3, wherein the heat generating component is mounted on the same surface as the surface of the wiring board on which the dew condensation detection element is mounted. The dew condensation sensor according to any one of claims 1 to 4, wherein the heat generating component is arranged in the vicinity of the conductor circuit pattern connected to the dew condensation detecting element. The invention according to any one of claims 1 to 5, wherein the dew condensation sensor is configured to determine that dew condensation has occurred after the lapse of the first predetermined time from the time when the dew condensation detecting element detects dew condensation. Condensation detection system equipped with a condensation sensor. The heat-generating component according to any one of claims 1 to 5, wherein the heat-generating component is configured to end heat generation after the lapse of a second specified time from the time when the dew condensation detection element is detected to be in a dry state. Condensation detection system equipped with a dew condensation sensor. The dew condensation detection element is the dew condensation sensor according to any one of claims 1 to 5, which is configured so that the next dew condensation detection is performed after the lapse of a third specified time from the end of heat generation of the heat generating component. Condensation detection system equipped. A refrigerator provided with the dew condensation detection system according to any one of claims 6 to 8.