WO2020170421A1

WO2020170421A1 - Refrigerator

Info

Publication number: WO2020170421A1
Application number: PCT/JP2019/006782
Authority: WO
Inventors: 梅田　達也; 康成大和
Original assignee: 三菱電機株式会社
Priority date: 2019-02-22
Filing date: 2019-02-22
Publication date: 2020-08-27

Abstract

This refrigerator comprises: at least one storage room; a door provided on the front side of the storage room; an operation panel that is housed in the door and is for setting and displaying the operation state of the refrigerator; a printed sheet that is provided on the front side of the operation panel and on which the shape of an operation switch is illustrated; a light-emitting diode that emits light toward the printed sheet so as to display the shape of the operation switch on the front side of the operation panel; a humidity detection means for detecting the humidity around the refrigerator; and a controller for controlling the operation state of the refrigerator. The controller has an energization amount control means that reduces the amount by which the light-emitting diode is energized when the humidity detected by the humidity detection means is at or above a designated humidity threshold.

Description

refrigerator

The present invention relates to a refrigerator having a storage room for storing stored items.

Conventionally, the refrigerator is provided with an internal light to illuminate the inside of the refrigerator and make it easy for the user to understand the storage status of food. In recent years, a light emitting diode (LED: Light Emitting Diode) has been used as an illumination for an interior light. In addition to the interior light, there is also a refrigerator in which an LED is used as an operation panel illumination for the user to set the operating state of the refrigerator. The interior light is a means for illuminating the interior of the refrigerator, and is used for the purpose of facilitating the user's grasp of the food storage status in the interior. The operation panel illumination is provided in the operation unit for setting the operation mode of the refrigerator, and is used for the purpose of displaying the shape of the operation switch on the surface of the operation unit.

When using LEDs, there is a point that the junction temperature of the element must not exceed the allowable temperature. This is because if the element temperature of the LED exceeds the allowable junction temperature, the possibility of failure increases. Here, the permissible forward current is generally used as a design index for keeping the element temperature below the permissible junction temperature. The allowable forward current is the maximum amount of forward current that can be passed through the device within a range in which the junction temperature does not exceed the allowable temperature under a certain ambient temperature. Even with the same amount of electricity, if the ambient temperature is high, the element temperature is high. Therefore, generally, when the ambient temperature is high, the allowable current value is low.

The easiest way to energize the LED within the range that does not exceed the permissible current value is to check the permissible current value corresponding to the highest ambient temperature that can be assumed in the actual usage environment, and energize the LED within that range. is there. However, in that case, even when the ambient temperature is not high, the LED is energized assuming the situation where the ambient temperature is the highest, so that the brightness of the LED is sacrificed.

Therefore, a refrigerator has been proposed in which the LEDs are energized with an energization amount that optimizes the brightness within a range that does not exceed the allowable current value, corresponding to the allowable current value that changes for each ambient temperature (for example, , Patent Document 1).

JP, 2008-275289, A

The refrigerator of Patent Document 1 can achieve both long life and brightness of the LED by selecting the energization amount of the LED in consideration of the ambient temperature of the LED, but does not consider the humidity around the LED. Generally, when electricity is applied to an electronic device in an environment with high humidity, the phenomenon of ion migration is accelerated, and electrical defects such as insulation defects are likely to occur on the electronic device and a printed circuit board on which the electronic device is mounted. As a result, the device life may be significantly reduced. Therefore, when the refrigerator of Patent Document 1 is used in an environment of relatively high humidity, the life of the LED may be significantly reduced.

The present invention has been made to solve the above problems, and provides a refrigerator capable of extending the life of a light emitting diode used as a light source even when the refrigerator is used in a high humidity environment. To do.

A refrigerator according to the present invention includes at least one storage room, a door provided on the front surface of the storage room, an operation panel that is stored in the door and is used for setting and displaying an operating state of the refrigerator, and the operation panel. A print sheet provided on the front surface of the operation switch, in which the shape of the operation switch is represented, and a light emitting diode which reflects the shape of the operation switch on the front surface of the operation panel by irradiating the print sheet with light; Humidity detection means for detecting ambient humidity, and a controller for controlling the operating state of the refrigerator, the controller, when the humidity detected by the humidity detection means is a predetermined humidity threshold or more, It has an energization amount control means for reducing the energization amount to the light emitting diode.

Further, the refrigerator according to the present invention includes at least one storage room, a door provided in front of the storage room, an operation panel stored in the door, for setting and displaying an operating state of the refrigerator, and A print sheet provided on the front surface of the operation panel, in which the shape of the operation switch is represented, and a light emitting diode which projects the shape of the operation switch on the front surface of the operation panel by irradiating the print sheet with light, Humidity detection means for detecting the humidity around the refrigerator, temperature detection means for detecting the temperature around the refrigerator, and a controller for controlling the operating state of the refrigerator, the controller, the humidity detection means When the humidity detected by the above is equal to or higher than a predetermined humidity threshold and the temperature detected by the temperature detecting means is equal to or higher than the predetermined temperature threshold, an energization amount control means for decreasing the energization amount to the light emitting diode Is to have.

According to the present invention, the energization amount of the light emitting diode is reduced in a high humidity environment, so that the progress of ion migration generated in the light emitting diode can be suppressed. Therefore, the life of the light emitting diode can be extended even in a high humidity environment.

It is an outline schematic diagram showing an example of a refrigerator concerning Embodiment 1 of the present invention. It is a side surface perspective view of the refrigerator shown in FIG. It is a front schematic diagram which shows the state which opened the door of the refrigerator compartment shown in FIG. It is a figure which shows one structural example of the operation panel shown in FIG. It is a figure which shows one structural example of the main control board shown in FIG. It is a figure which shows one structural example of the panel control board shown in FIG. FIG. 7 is a functional block diagram showing a configuration example of a controller shown in FIG. 5 and a panel controller shown in FIG. 6. 5 is a graph showing an energization current when turning on the LED shown in FIG. 4 in the first embodiment. It is a figure for demonstrating the specific example of control of the energization amount of LED shown in FIG. 7 is a time chart showing an example of control of a duty ratio when the ambient humidity of the refrigerator shown in FIG. 1 is equal to or higher than a humidity threshold in the first embodiment. FIG. 7 is a diagram showing an example of a case where the ROM shown in FIG. 6 stores set values in a table format in the first embodiment. It is a flowchart which shows the operation procedure of the refrigerator which concerns on Embodiment 1 of this invention. It is a figure for demonstrating operation|movement of the electricity supply amount control means of the refrigerator which concerns on Embodiment 2 of this invention. FIG. 7 is a diagram showing an example of a case where the ROM shown in FIG. 6 stores set values in a table format in the second embodiment. It is a flowchart which shows the operation procedure of the refrigerator which concerns on Embodiment 2 of this invention. It is a figure for demonstrating operation|movement of the electricity supply amount control means of the refrigerator which concerns on Embodiment 3 of this invention. FIG. 9 is a diagram showing an example of a case where the ROM shown in FIG. 5 stores set values in a table format in the third embodiment. It is a flowchart which shows the operation procedure of the refrigerator which concerns on Embodiment 3 of this invention.

Embodiment 1.
The configuration of the refrigerator according to the first embodiment will be described. FIG. 1 is a schematic external view showing an example of a refrigerator according to Embodiment 1 of the present invention. FIG. 2 is a side perspective view of the refrigerator shown in FIG. As shown in FIG. 1 and FIG. 2, the refrigerator 1 has a refrigerating room 18,

freezing rooms

41 and 44, a switching room 42, and a vegetable room 43 as storage rooms for accommodating stored items such as foods. The refrigerator compartment 18 and the vegetable compartment 43 are kept at the refrigeration temperature. The refrigerating temperature is, for example, a temperature range of 0 to 10°C. The freezer compartment 41 is kept at a freezing temperature lower than the refrigerating temperature. The freezing temperature is, for example, a temperature of −18° C. or lower. The switching chamber 42 is a storage chamber in which the user can select which of the refrigerating temperature and the freezing temperature the stored item is stored in. In FIG. 2, the partition between the storage compartments such as the refrigerating compartment 18 and the freezing compartment 41, the doors of the refrigerating compartment 18 and the freezing compartment 41, and the heat insulating material that covers the box body including the plurality of storage compartments are hatched. Showing.

As shown in FIG. 1, the refrigerating compartment 18 is a double-door storage compartment in which a left door 7a and a right door 7b are provided on the front side of the refrigerator 1 (in the direction opposite to the Y-axis arrow). As shown in FIGS. 1 and 2, an operation panel 6 is provided on the front surface of the left door 7a of the refrigerating compartment 18 for the user to set operating conditions such as adjusting the temperature of each storage compartment. The operation panel 6 is used not only for setting the operating state of the refrigerator 1 but also for displaying the operating state of the refrigerator 1.

As shown in FIG. 2, the refrigerator 1 includes a compressor 2 that compresses and discharges a refrigerant, a cooler 3 that functions as an evaporator of a refrigeration cycle, an expansion valve and a heat radiation pipe (not shown), and a refrigeration cycle. And a main control board 13 for controlling. The radiating pipe functions as a condenser. The main control board 13 is provided on the back side of the refrigerator 1 (in the Y-axis arrow direction). The refrigerator 1 includes an air passage 5 through which the cool air cooled by the cooler 3 flows, a blower fan 4 for supplying the cool air to each storage room, and a refrigerating compartment damper 10 for adjusting the flow rate of the cool air flowing into the refrigerating compartment 18. It is provided. The air passage 5 and the refrigerator compartment damper 10 are provided on the back side of the refrigerator 1. The refrigerator 1 controls a refrigeration cycle in which a refrigerant is circulated in a refrigerant circuit including a compressor 2 and a cooler 3, and cool air in the vicinity of the cooler 3 is circulated in the refrigerator 1 to cool a plurality of storage chambers.

Further, in the refrigerator 1, an inside lamp 12 that illuminates the inside of the refrigerating compartment 18, a refrigerating compartment thermistor 9 that is a thermistor that detects a refrigerating temperature in the refrigerating compartment 18, and a cooling that is a thermistor that detects the temperature of the cooler 3 are included. A thermistor 11 is provided. The interior light 12 is provided in the refrigerating compartment 18 as lighting for the refrigerating compartment 18. The light source of the interior lamp 12 is, for example, an LED. The temperature detected by the cooler thermistor 11 corresponds to the freezing temperature.

The refrigerator 1 is provided with a humidity detecting unit 14 that detects the humidity around the refrigerator 1, a temperature detecting unit 15 that detects the temperature around the refrigerator 1, and an illuminance detecting unit 31 that detects the brightness around the refrigerator. ing. The temperature detecting means 15 is provided on the operation panel 6. The temperature detecting means 15 is, for example, a thermistor. The humidity detecting means 14 is installed on the upper surface of the refrigerator 1, and the illuminance detecting means 31 is installed on the front surface of the left door 7a or the right door 7b of the refrigerating room 18. The humidity detecting means 14 is, for example, a humidity sensor such as a polymer humidity sensor and a ceramics humidity sensor. The illuminance sensor is, for example, an optical sensor such as a light amount sensor. The positions of the humidity detecting means 14 and the illuminance detecting means 31 are not limited to the positions shown in FIG.

3 is a schematic front view showing a state in which the door of the refrigerating compartment shown in FIG. 1 is opened. When the door of the refrigerator compartment 18 is a double door as shown in FIG. 1, the user can open and close each of the left door 7a and the right door 7b independently. A door switch 8 for detecting the open/closed state of the left door 7a and the right door 7b is provided on the front surface of the refrigerator compartment 18. When the door of the refrigerating chamber 18 is a double door, as shown in FIG. 2, the left door 7a is provided with a door partition member 16 for suppressing the leakage of cold air. A heater 17 is provided inside the door partition member 16 to prevent dew condensation on the door partition member 16.

In the first embodiment, as shown in FIGS. 1 and 2, the refrigerator 1 according to the first embodiment will be described in the case of having a configuration in which a plurality of storage chambers are provided in a box body. The numbers and are not limited to those shown in FIG. The number of storage rooms provided in the refrigerator 1 is not limited to a plurality, and may be one. In this case, the temperature of one storage chamber may be a refrigerating temperature or a freezing temperature. When the whole storage room is kept at a freezing temperature, there is a commercial freezing storage. Further, the door provided with the operation panel 6 is not limited to the left door 7a and may be the right door 7b. The storage room in which the operation panel 6 is provided is not limited to the refrigerating room 18. The door of the refrigerating room 18 is not limited to the double-opening door, but may be a single-opening door.

The configuration of the operation panel 6 shown in FIG. 1 will be described. FIG. 4 is a diagram showing a configuration example of the operation panel shown in FIG. The operation panel 6 is provided in the left door 7a. The operation panel 6 is provided with an operation panel control board 20. An LED 21, which serves as a light source, is mounted on the operation panel control board 20. On the front side of the refrigerator 1 of the operation panel 6, a print sheet 23 having a shape 23a of an operation switch is provided. The print sheet 23 is a sheet that transmits light, and the shape of the operation switch 23a is drawn with ink that does not transmit light. The print sheet 23 is arranged between the LED 21 and the surface member 22 of the left door 7a. The surface member 22 of the left door 7a is a material that transmits light. When the LED 21 emits light in the direction of the surface member 22 of the left door 7a, the shape 23a of the operation switch is displayed on the surface member 22. Further, as shown in FIG. 4, the operation panel 6 is provided with operation switch electrodes 24 between the print sheet 23 and the LEDs 21. The operation switch electrode 24 may be arranged between the surface member 22 of the left door 7a and the print sheet 23. The operation switch electrode 24 is arranged at a position that does not prevent the light emitted from the LED 21 from irradiating the surface member 22 with the shape 23 a of the operation switch.

The operation panel 6 described with reference to FIG. 4 is stored in the space provided on the left door 7a. In order to prevent the LED 21 from being affected by the humidity around the refrigerator 1 as much as possible, the configuration including the operation panel control board 20, the print sheet 23, and the operation switch electrode 24 on which the LED 21 is mounted is provided in a gas-impermeable housing. It may be sealed. However, if an attempt is made to seal these components, it is necessary to take measures to prevent outside air from entering along the power supply wiring and the signal line connected to the operation panel control board 20, which increases the manufacturing cost. .. Further, even if the wall of the casing surrounding these components is transparent, the light emitted by the LED 21 is attenuated by the wall of the casing, and the shape 23a of the operation switch is difficult for the user to see. In order to make the shape 23a of the operation switch visible to the user, it is necessary to increase the luminous intensity of the LED 21. If the luminous intensity of the LED 21 is to be increased, the current flowing through the LED 21 must be increased, and the life of the LED 21 is shortened. Therefore, it is difficult to prevent the LED 21 provided on the operation panel 6 from being affected by the outside air with a simple structure, and the influence of the environment around the refrigerator 1 on the LED 21 cannot be ignored.

Next, the configurations of the main control board shown in FIG. 2 and the panel control board shown in FIG. 4 will be described. FIG. 5 is a diagram showing a configuration example of the main control board shown in FIG. FIG. 6 is a diagram showing a configuration example of the panel control board shown in FIG. FIG. 7 is a functional block diagram showing a configuration example of the controller shown in FIG. 5 and the panel controller shown in FIG.

As shown in FIG. 5, the main control board 13 includes a controller 19 and an EEPROM (Electrically Erasable Programmable ROM) 30. The controller 19 is, for example, a microcomputer. The controller 19 has a ROM (Random Access Memory) 51, a RAM (Random Access Memory) 52, and a CPU (Central Processing Unit) 53. The ROM 51 stores a program for executing the function of temperature determination required for temperature control of the freezing temperature and the refrigerating temperature, and the function of a timer for measuring time. The CPU 53 executes arithmetic processing according to the program stored in the ROM 51. The RAM 52 stores information such as numerical values calculated in the process of arithmetic processing executed by the CPU 53. The nonvolatile memory provided on the main control board 13 is not limited to the EEPROM 30. The non-volatile memory may be, for example, a flash memory. The EEPROM 30 may be provided in the controller 19.

As shown in FIG. 6, the operation panel control board 20 has a panel controller 25 which is a controller for the operation panel, and an LED drive circuit 26 which supplies electric power to the LEDs 21. The panel controller 25 is, for example, a microcomputer. The panel controller 25 has a ROM 61, a RAM 62, and a CPU 63. The ROM 61 stores a control program for executing an input determination function of the operation switch electrode 24 necessary for controlling the operation panel 6 and a function of controlling lighting and extinguishing of the LED 21. The CPU 63 executes arithmetic processing according to the control program stored in the ROM 61. The RAM 62 stores information such as numerical values calculated in the course of arithmetic processing executed by the CPU 63.

Although FIG. 7 shows a configuration in which the controller 19 and the panel controller 25 are provided on different substrates, the controller 19 and the panel controller 25 may be integrally configured and provided on the same substrate. For example, the controller 19 shown in FIG. 5 may have the function of the panel controller 25 shown in FIG. When the CPU 53 executes the program stored in the ROM 51, the refrigeration cycle means 71 shown in FIG. 7 is configured. The CPU 63 executes the control program stored in the ROM 61 to configure the energization amount control means 72 shown in FIG. 7.

The controller 19 controls the temperature of a storage room such as the refrigerating room 18, energization control of the heater 17, records operation history information, and performs mutual communication with the panel controller 25.

Of the temperature control of the storage compartments such as the refrigerating compartment 18, the temperature control of the refrigerating compartment 18 will be described. The refrigeration cycle means 71 controls the opening/closing time of the refrigerating compartment damper 10 based on the detection values detected by the refrigerating compartment thermistor 9 and the temperature detecting means 15, thereby adjusting the flow of cold air flowing into the refrigerating compartment 18. Thereby, the temperature of the refrigerator compartment 18 is controlled. Further, the refrigeration cycle means 71 controls the opening degree of the expansion valve and the operating frequency of the compressor 2 which are not shown, based on the detection value detected by the cooler thermistor 11. As a result, the function of the cooler 3 as an evaporator is controlled, and not only the temperature of the refrigerating chamber 18 but also the temperatures of the freezing

chambers

41 and 44 are controlled.

Regarding the energization control of the heater 17, the refrigeration cycle means 71 controls the electric power supplied to the heater 17 based on the detection value detected by the humidity detection means 14. Regarding the recording of the operation history information, the refrigeration cycle means 71 records the cumulative operating time TO of the refrigerator 1, the setting state of the refrigerator 1 and the time series change of the operating state in the EEPROM 30.

The mutual communication of the controller 19 with the panel controller 25 will be described. When the controller 19 receives an instruction signal, which is a signal indicating the instruction content input by the user via the operation panel 6, from the panel controller 25, the refrigeration cycle means 71 performs the above-mentioned temperature control corresponding to the instruction content. The instruction content is, for example, a set value of the refrigeration temperature. When the refrigeration cycle means 71 receives the detection value of the temperature detection means 15 from the panel controller 25, the refrigeration cycle means 71 uses the received detection value for the above temperature control. Further, the refrigeration cycle means 71 transmits the detection values of the humidity detecting means 14 and the illuminance detecting means 31 to the panel controller 25. The refrigeration cycle means 71 transmits information on the operation history time recorded in the EEPROM 30 to the panel controller 25.

Explain the other controls performed by the controller 19. When the door switch 8 detects the open state, the controller 19 turns on the interior lamp 12, and when the door switch 8 detects the closed state, the controller 19 turns off the interior lamp 12.

The panel controller 25 shown in FIG. 6 controls the turning on and off of the LED 21, obtains outside air temperature information, and performs mutual communication with the controller 19.

Explain the control of turning on and off the LED 21. The panel controller 25 constantly monitors the fluctuation of the ground capacitance of the operation switch electrode 24. When the user touches the shape 23a of the operation switch displayed on the surface member 22, the ground capacitance of the operation switch electrode 24 located behind the shape 23a of the operation switch changes. The panel controller 25 can determine that the user has operated the operation panel 6 by detecting this variation. When the panel controller 25 detects an operation on the operation switch shape 23 a, for example, the LED 21 behind the operation switch shape 23 a is turned on and the operation switch shape 23 a is displayed on the surface member 22. In this way, the user is notified of the operation performed by the user. Further, the panel controller 25 projects the shape 23 a of the operation switch on the surface member 22 to notify the user of the operation result or prompt the user for the next operation. A buzzer (not shown) may be provided on the operation panel 6. In this case, the panel controller 25 may sound a buzzer to notify the user of the operation result.

Regarding acquisition of outside air temperature information, the energization amount control means 72 acquires a detection value from the temperature detection means 15 which detects the temperature around the refrigerator 1 at a constant cycle.

The mutual communication of the panel controller 25 with the controller 19 will be described. When the user inputs an instruction via the operation panel 6, the panel controller 25 transmits an instruction signal indicating the input instruction content to the controller 19. When the user inputs an instruction to change the setting state of the refrigerator 1 via the operation panel 6, the panel controller 25 transmits an instruction signal indicating the input change contents to the controller 19. The energization amount control means 72 transmits the detection value acquired from the temperature detection means 15 to the refrigeration cycle means 71 of the controller 19.

Next, control of the energization amount performed by the energization amount control means 72 for the LED 21 will be described.

FIG. 8 is a graph showing an energization current when the LED shown in FIG. 4 is turned on in the first embodiment. The vertical axis in FIG. 8 represents the current [A] flowing in the LED 21 in the forward direction, and the horizontal axis represents the relative humidity [%RH]. In the first embodiment, when the humidity Hd detected by the humidity detecting means 14 is high humidity equal to or higher than the determined humidity threshold value Hth, the energization amount control means 72 causes the energizing current Cd of the LED 21 to determine the energizing amount Pth0. The LED drive circuit 26 is controlled so that The energization amount Pth0 at high humidity is set to a lower value than the energization amount Pn when the humidity Hd detected by the humidity detecting means 14 is less than the humidity threshold value Hth. The energization amount Pn is a normal energization amount. The energization amount is the average value of the current flowing per unit time.

FIG. 9 is a diagram for explaining a specific example of the control of the energization amount of the LED shown in FIG. When the LED 21 is turned on, the energization amount control unit 72 adjusts the ON time Ton for driving the LED driving circuit 26 that applies a predetermined voltage to the LED 21 to supply a current, for each energizing cycle Tk. Control the amount of electricity supplied to. Specifically, the energization amount control means 72 outputs to the LED drive circuit 26 a pulse voltage of a square wave indicating the on time Ton at a constant energization period Tk. FIG. 9 shows the case where the energization amount Pn is the energization amount at the normal time, the energization period Tk is 10 ms, the on time Ton is 6 ms, and the off time Toff is 4 ms.

In the pulse waveform shown in FIG. 9, the LED drive circuit 26 supplies electric power to the LED 21 during the energization period Tk, and when the output of the square wave pulse voltage is Ton, the LED 21 is turned on. In the energization period Tk, the ratio of the time Ton indicated by the square wave in the ON state of the LED drive circuit 26 to the energization period Tk is defined as the ON-DUTY rate. Hereinafter, this ON-DUTY rate will be referred to as a duty ratio Du. The energization amount control means 72 can adjust the average value of the current flowing through the LED 21 in the forward direction by adjusting the energization rate Du. The energization amount control unit 72 can increase the energization rate Du to increase the average energization current amount and decrease the energization rate Du to decrease the average energization current amount.

FIG. 10 is a time chart showing an example of control of the energization rate when the humidity around the refrigerator shown in FIG. 1 is equal to or higher than the humidity threshold value in the first embodiment. The energization amount control means 72 sets the energization rate Du to the energization rate Dun when the humidity Hd around the refrigerator 1 is not high, and sets the energization rate Du to the energization rate Dud when the humidity Hd is high. In the example shown in FIG. 10, the duty ratio Dun when the humidity is normal is 60%, and the duty ratio Dud when the humidity is high is 40%.

In the example shown in FIG. 10, in the energization cycle Tk1, the humidity Hd detected by the humidity detector 14 is not high, so the energization amount controller 72 outputs the normal energization rate Dun to the LED drive circuit 26. ing. In the energization cycle Tk2, the humidity Hd detected by the humidity detection unit 14 is high humidity equal to or higher than the humidity threshold value Hth, and therefore the energization amount control unit 72 outputs the energization rate Dud at high humidity to the LED drive circuit 26. As a result, the forward current of the LED 21 at high humidity can be reduced as compared to the normal forward current.

The ROM 61 shown in FIG. 6 stores set values including the duty ratio Dud at high humidity, the duty ratio Dun at normal times, and the humidity threshold value Hth. The ROM 61 stores these set values in the form of a table, for example. FIG. 11 is a diagram showing an example of the case where the ROM shown in FIG. 6 stores the setting values in a table format in the first embodiment. The storage unit that stores these set values is not limited to the ROM 61 of the panel controller 25. For example, the EEPROM 30 shown in FIG. 5 may store the set value.

Next, the operation of the refrigerator 1 according to the first embodiment will be described. FIG. 12: is a flowchart which shows the operation procedure of the refrigerator which concerns on Embodiment 1 of this invention.

Every energization cycle Tk, the energization amount control means 72 acquires the humidity Hd detected by the humidity detection means 14 from the humidity detection means 14 via the controller 19 (step S101). The energization amount control means 72 determines whether or not the humidity Hd is equal to or higher than the humidity threshold value Hth (step S102). When the humidity Hd is equal to or higher than the humidity threshold value Hth, the energization amount control unit 72 determines that the humidity around the refrigerator 1 is high, and outputs the energization rate Dud to the LED drive circuit 26 (step S103). The LED drive circuit 26 supplies electric power to the LED 21 according to the duty ratio Dud. As a result, a current having an energization amount Pth0 lower than that in the normal state flows through the LED 21.

On the other hand, as a result of the determination in step S102, when the humidity Hd is less than the humidity threshold value Hth, the energization amount control unit 72 determines that the humidity around the refrigerator 1 is not high humidity, and sets the energization rate Dun to the LED drive circuit 26. Output (step S104). The LED drive circuit 26 supplies electric power to the LED 21 according to the duty ratio Dun. As a result, a current having the normal energization amount Pn flows through the LED 21. In this way, when the humidity around the refrigerator 1 is high, the amount of current flowing through the LED 21 becomes small and the life of the LED 21 can be extended.

The refrigerator 1 according to the first embodiment includes an operation panel 6 provided on the front surface of the storage room, a print sheet 23 provided on the front surface of the operation panel 6, an LED 21 for irradiating the print sheet 23 with light, and a refrigerator 1 It has a humidity detecting means 14 for detecting the surrounding humidity and a controller 19. The controller 19 has an energization amount control unit 72 that reduces the amount of energization to the LED 21 when the humidity Hd detected by the humidity detection unit 14 is equal to or higher than the humidity threshold value Hth.

According to the first embodiment, the energization amount of the LED 21 is reduced in a high humidity environment, so that the progress of ion migration generated in the LED 21 can be suppressed. Therefore, the LED 21 is not sealed by the housing, and the life of the LED 21 can be extended without significantly impairing the life of the LED 21 even in a high humidity environment. As a result, the usage period of the refrigerator 1 can be extended.

(Modification 1)
The case where the energization amount control means 72 controls the energization amount to the LED 21 according to the humidity around the refrigerator 1 has been described with reference to FIGS. 1 to 12. , The amount of electricity supplied to the LED 21 may be controlled. For example, comparing the appearances of the operation panel 6 when the surroundings of the refrigerator 1 are bright and when the surroundings of the refrigerator 1 are dark, when the surroundings of the refrigerator 1 are dark, even if the energization amount of the LED 21 is darker than normal, the user operates the operating panel. The switch shape 23a of 6 can be recognized. Therefore, when the illuminance Ld detected by the illuminance detection unit 31 is less than the predetermined illuminance threshold Lth, the energization amount control unit 72 reduces the energization amount of the LED 21 in the same manner as the control shown in FIG.

Also in the first modification, the life of the LED 21 can be extended. The energization amount control of the first modification may be combined with the flowchart shown in FIG. In this case, the life of the LED 21 can be further extended.

Embodiment 2.
The second embodiment controls the energization amount of the LED 21 of the operation panel 6 in accordance with not only the humidity but also the temperature as the environment around the refrigerator 1. In the second embodiment, the same components as those described in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The configuration of the refrigerator 1 according to the second embodiment will be described. FIG. 13: is a figure for demonstrating operation|movement of the electricity amount control means of the refrigerator which concerns on Embodiment 2 of this invention. In FIG. 13, among the three graphs showing time-series changes with time on the horizontal axis, the vertical axis of the upper graph is temperature, the vertical axis of the middle graph is relative humidity, and the vertical axis of the lower graph is pulse voltage. Is.

FIG. 13 shows an example of the case where the energization amount control means 72 determines the energization rate Du output to the LED drive circuit 26 from the temperature Td detected by the temperature detection means 15 and the humidity Hd detected by the humidity detection means 14. The duty factor Du when the surroundings of the refrigerator 1 are high temperature and high humidity is Dud, and the duty factor Du when the surroundings of the refrigerator 1 is neither high temperature nor high humidity is the duty factor Dun. FIG. 13 shows an example in which the duty ratio Dud is 40% and the duty ratio Dun is 60%. Further, in the example shown in FIG. 13, when the temperature Td is equal to or higher than the predetermined temperature threshold Tth, the temperature is high, and when the humidity Hd is equal to or higher than the humidity threshold Hth, the humidity is high.

Referring to FIG. 13, at the initial stage of the energization cycle Tk1, the temperature Td detected by the temperature detecting means 15 is less than the temperature threshold Tth, and the humidity Hd detected by the humidity detecting means 14 is also less than the humidity threshold Hth. Therefore, in the energization period Tk1, the energization amount control unit 72 outputs the normal energization rate Dun to the LED drive circuit 26. In the initial stage of the energization cycle Tk2, the temperature Td detected by the temperature detecting means 15 is equal to or higher than the temperature threshold Tth, and the humidity Hd detected by the humidity detecting means 14 is equal to or higher than the humidity threshold Hth. Therefore, in the energization period Tk2, the energization amount control unit 72 outputs the energization rate Dud of high temperature and high humidity to the LED drive circuit 26.

On the other hand, in the initial stage of the energization cycle Tk3, the temperature Td around the refrigerator 1 is equal to or higher than the temperature threshold Tth, but the humidity Hd around the refrigerator 1 is lower than the humidity threshold Hth. Therefore, the energization amount control means 72 outputs the normal energization rate Dun to the LED drive circuit 26. Further, in the energization cycle Tk4, the humidity Hd is equal to or higher than the humidity threshold value Hth, but the temperature Td is lower than the temperature threshold value Tth. Therefore, the energization amount control means 72 outputs the normal energization rate Dun to the LED drive circuit 26.

The ROM 61 shown in FIG. 6 stores set values including the duty ratio Dud at high temperature and high humidity, the duty ratio Dun at normal times, the temperature threshold value Tth, and the humidity threshold value Hth. The ROM 61 may store these set values in the form of a table as shown in FIG. 14, for example. FIG. 14 is a diagram showing an example of a case where the ROM shown in FIG. 6 stores the set values in a table format in the second embodiment. The storage means for storing these set values may be the EEPROM 30 shown in FIG.

Next, the operation of the refrigerator 1 according to the second embodiment will be described. FIG. 15: is a flowchart which shows the operation procedure of the refrigerator which concerns on Embodiment 2 of this invention.

Every energization cycle Tk, the energization amount control means 72 acquires the humidity Hd detected by the humidity detection means 14 from the humidity detection means 14 via the controller 19 (step S201). The energization amount control means 72 determines whether or not the humidity Hd is equal to or higher than the humidity threshold value Hth (step S202). When the humidity Hd is equal to or higher than the humidity threshold value Hth, the energization amount control unit 72 acquires the temperature Td detected by the temperature detection unit 15 from the temperature detection unit 15 (step S203). Subsequently, the energization amount control unit 72 determines whether the acquired temperature Td is equal to or higher than the temperature threshold Tth (step S204). When the temperature Td is equal to or higher than the temperature threshold Tth, the energization amount control unit 72 determines that the environment around the refrigerator 1 is high temperature and high humidity, and outputs the energization rate Dud to the LED drive circuit 26 (step S205). The LED drive circuit 26 supplies electric power to the LED 21 according to the duty ratio Dud. As a result, a current having an energization amount Pth0 lower than that in the normal state flows through the LED 21.

On the other hand, as a result of the determination in step S202, when the humidity Hd is less than the humidity threshold value Hth, the energization amount control unit 72 determines that the humidity around the refrigerator 1 is not high humidity, and sets the energization rate Dun to the LED drive circuit 26. Output (step S206). When the temperature Td is lower than the temperature threshold value Tth as a result of the determination in step S204, the energization amount control unit 72 determines that the temperature is not high around the refrigerator 1 and outputs the energization rate Dun to the LED drive circuit 26. (Step S206). The LED drive circuit 26 supplies electric power to the LED 21 according to the duty ratio Dun. As a result, a current having the normal energization amount Pn flows through the LED 21. In this way, when the temperature around the refrigerator 1 is high and the humidity is high, the amount of current flowing through the LED 21 becomes small and the life of the LED 21 can be extended.

In the refrigerator 1 according to the second embodiment, when the humidity Hd detected by the humidity detecting means 14 is the humidity threshold value Hth or more and the temperature Td detected by the temperature detecting means 15 is the temperature threshold value Tth or more, the LED 21 is turned on. The amount of electricity supplied is reduced compared to the normal state.

According to the second embodiment, the energization amount of the LED 21 becomes small when the temperature around the refrigerator 1 is high and the humidity is high. Therefore, it is possible to prevent the life of the LED 21 from being impaired due to a high load environment due to humidity and temperature.

Embodiment 3.
In the third embodiment, the energization amount of the LED 21 of the operation panel 6 is controlled according to the cumulative operating time of the refrigerator 1. In the third embodiment, the same components as those described in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. The third embodiment can be applied to both the first and second embodiments.

The configuration of the refrigerator according to the third embodiment will be described. FIG. 16: is a figure for demonstrating operation|movement of the electricity amount control means of the refrigerator which concerns on Embodiment 3 of this invention. In FIG. 16, among the two graphs showing the time series changes with the horizontal axis, the vertical axis of the upper graph is the cumulative operating time, and the lower vertical axis is the pulse voltage.

When n is an arbitrary integer of 2 or more, in FIG. 16, the cumulative operating time TO of the refrigerator 1 stored in the EEPROM 30 is less than the determined operating time threshold TOth during the energization period Tk1 to Tk(n-1). Is. Therefore, the energization amount control means 72 outputs the normal energization rate Dun to the LED drive circuit 26. On the other hand, after the energization period Tkn, the cumulative operation time TO of the refrigerator 1 is equal to or greater than the operation time threshold value TOth, so the energization amount control unit 72 outputs the energization rate Dup in the long-time operation to the LED drive circuit 26. FIG. 16 shows an example in which the duty ratio Dup is 80% and the duty ratio Dun is 60%. Further, the case where the cumulative operating time TO is equal to or more than the operating time threshold value TOth is defined as long-time operation.

Generally speaking, LEDs deteriorate over time when used for a long period of time, and even with the same energizing current, the longer the elapsed time, the lower the illuminance due to the light emitted from the LEDs. Therefore, for example, the appearance of the operation switch shape 23a illuminated by the LED 21 becomes poor. Therefore, as described with reference to FIG. 16, when the cumulative operating time TO of the refrigerator 1 becomes long, the duty factor Du of the LED 21 is increased to compensate for the decrease in illuminance due to the aged deterioration of the LED 21. it can.

Note that the EEPROM 30 shown in FIG. 5 records the cumulative operating time TO. The ROM 51 shown in FIG. 5 stores set values including the energization rate Dup after long-time operation, the energization rate Dun under normal conditions, and the operation time threshold value TOth. The ROM 51 may store these set values in the form of a table as shown in FIG. 17, for example. FIG. 17 is a diagram showing an example of a case where the ROM shown in FIG. 5 stores the setting values in a table format in the third embodiment. The storage means for storing these set values may be the EEPROM 30 shown in FIG. Further, the case where the EEPROM 30 records the cumulative operating time TO will be described, but the memory that records the cumulative operating time TO is not limited to the EEPROM 30. The memory for recording the cumulative operating time TO is preferably a flash memory or a non-volatile memory such as the EEPROM 30. This is because these non-volatile memories can retain the stored information even when the power supply is stopped.

Next, the operation of the refrigerator 1 according to the third embodiment will be described. FIG. 18 is a flowchart showing an operation procedure of the refrigerator according to the third embodiment of the present invention.

For each energization cycle Tk, the energization amount control means 72 refers to the cumulative operating time TO stored in the EEPROM 30 (step S301). The energization amount control means 72 determines whether the cumulative operating time TO is equal to or greater than the operating time threshold TOth (step S302). When the cumulative operation time TO is equal to or greater than the operation time threshold value TOth, the energization amount control unit 72 determines that the refrigerator 1 has been operated for a long time, and outputs the energization rate Dup to the LED drive circuit 26 (step S303). The LED drive circuit 26 supplies electric power to the LED 21 according to the duty ratio Dup. As a result, a current having a higher energization amount than in the normal state flows through the LED 21.

On the other hand, as a result of the determination in step S302, when the cumulative operation time TO is less than the operation time threshold value TOth, the energization amount control unit 72 determines that the refrigerator 1 is not operated for a long time, and sets the energization rate Dun to the LED drive circuit 26. (Step S304). The LED drive circuit 26 supplies electric power to the LED 21 according to the duty ratio Dun. As a result, a current having a normal energizing amount flows through the LED 21. In this way, when it is determined that the refrigerator 1 has been operating for a long time based on the cumulative operating time TO of the refrigerator 1, the amount of current flowing through the LED 21 increases and the decrease in illuminance of the LED 21 is suppressed.

The refrigerator 1 according to the third embodiment increases the energization amount of the LED 21 when the cumulative operating time TO recorded by the EEPROM 30 is equal to or more than the operating time threshold TOth.

According to the third embodiment, it is possible to suppress a decrease in the illuminance of the LED 21 due to the long-term operation of the refrigerator 1. If the third embodiment is applied to any one of the first and second embodiments, the life of the LED 21 can be further extended.

1 refrigerator, 2 compressor, 3 cooler, 4 blower fan, 5 air passage, 6 operation panel, 7a left door, 7b right door, 8 door switch, 9 cold room thermistor, 10 cold room damper, 11 cooler thermistor, 12 internal light, 13 main control board, 14 humidity detecting means, 15 temperature detecting means, 16 door partition member, 17 heater, 18 refrigerating room, 19 controller, 20 operation panel control board, 21 LED, 22 surface member, 23 printing Seat, 23a operation switch shape, 24 operation switch electrode, 25 panel controller, 26 LED drive circuit, 30 EEPROM, 31 illuminance detection means, 41 freezing room, 42 switching room, 43 vegetable room, 51 ROM, 52 RAM, 53 CPU , 61 ROM, 62 RAM, 63 CPU, 71 refrigeration cycle means, 72 energization amount control means.

Claims

At least one storage room,
A door provided in front of the storage room,
An operation panel stored in the door for setting and displaying the operating state of the refrigerator,
A print sheet provided on the front surface of the operation panel and showing the shape of the operation switch,
A light emitting diode that projects the shape of the operation switch on the front surface of the operation panel by irradiating the print sheet with light,
Humidity detection means for detecting the humidity around the refrigerator,
A controller for controlling the operating state of the refrigerator,
The controller is
When the humidity detected by the humidity detecting means is equal to or higher than a predetermined humidity threshold value, it has an energization amount control means for decreasing the energization amount to the light emitting diode,
refrigerator.
At least one storage room,
A door provided in front of the storage room,
An operation panel stored in the door for setting and displaying the operating state of the refrigerator,
A print sheet provided on the front surface of the operation panel and showing the shape of the operation switch,
A light emitting diode that projects the shape of the operation switch on the front surface of the operation panel by irradiating the print sheet with light,
Humidity detection means for detecting the humidity around the refrigerator,
Temperature detection means for detecting the temperature around the refrigerator,
A controller for controlling the operating state of the refrigerator,
The controller is
When the humidity detected by the humidity detecting means is equal to or higher than a predetermined humidity threshold and the temperature detected by the temperature detecting means is equal to or higher than the predetermined temperature threshold, the amount of electricity supplied to the light emitting diode is reduced. Having an energization amount control means,
refrigerator.
Further comprising an illuminance detection means for detecting the brightness around the refrigerator,
The energization amount control means,
The refrigerator according to claim 1 or 2, wherein when the illuminance detected by the illuminance detection unit is less than a predetermined illuminance threshold, the energization amount of the light emitting diode is reduced.
The controller has a memory for recording the cumulative operating time of the refrigerator,
The energization amount control means,
The refrigerator according to claim 1 or 2, wherein when the cumulative operating time recorded by the memory is equal to or more than a predetermined operating time threshold value, the energization amount of the light emitting diode is increased.