JP5260450B2 - refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a refrigerator with improved reliability of pressure-reducing operation by comprising a pressure-reduced storage chamber. <P>SOLUTION: The refrigerator comprises a pressure reducing means, the pressure-reduced storage chamber with its inside decompressed by the pressure reducing means, a pressure-reduced storage chamber temperature detection means detecting temperature of the pressure-reduced storage chamber, and a control means controlling the pressure reducing means. When the detected temperature by the pressure-reduced storage chamber temperature detection means is at predetermined temperature or higher, the control means reduces a pressure-reducing amount by the pressure reducing means compared with the case that the detected temperature is lower than the predetermined temperature. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a refrigerator.

  As a conventional refrigerator, Patent Document 1 includes a decompression storage chamber that sucks and decompresses internal air by a vacuum pump. A pressure sensor is provided as air pressure detection means in the decompression storage chamber, and the detected pressure is a predetermined pressure. It is described that the vacuum pump is operated when higher, and the vacuum pump is stopped and operated intermittently when lower.

  Patent Document 2 describes a configuration in which the internal pressure of the decompression storage space during decompression is changed according to the suction time of the vacuum pump and the opening degree of the exhaust pipe.

Japanese Patent Laid-Open No. 10-103849 JP 2004-20113 A

  However, in Patent Document 1, the pressure value when the vacuum pump is turned on or off is not specified, and when the vacuum pump is intermittently operated, repetition of operation / stop is increased, and unnecessary driving time is generated. There was a problem.

  Moreover, in patent document 2, when food is stored in the decompression storage space, the volume that can be sucked by the vacuum pump is apparently reduced. In other words, the volume of the storage space differs depending on the use situation, and there is a problem that it is difficult to control the pressure to a predetermined pressure with a fixed suction time.

  In addition, since the vacuum storage chamber is composed of a highly sealed container, when the ambient temperature changes, the pressure in the vacuum storage chamber changes according to Boyle-Charles' law. However, Patent Documents 1 and 2 do not clearly indicate how to operate the vacuum pump when the pressure in the vacuum storage chamber decreases due to a decrease in the ambient temperature. For this reason, there is a problem that the vacuum storage chamber is damaged by driving the vacuum pump so that the pressure is lower than the strength of the vacuum storage chamber.

  Further, there is a problem that the load of the motor of the vacuum pump exceeds the starting torque and the motor is locked.

  In view of the above problems, an object of the present invention is to provide a refrigerator that includes a decompression storage chamber and has improved decompression operation reliability.

In order to achieve the above object, a decompression storage chamber provided in the refrigerator body, a decompression means that is a vacuum pump for decompressing the decompression storage chamber, and a decompression storage chamber temperature detection means for detecting the temperature of the decompression storage chamber; Control means for controlling the stopping and stopping of the decompression means , and when the temperature detected by the decompression storage chamber temperature detection means is equal to or higher than a predetermined temperature, the control means is less than the vacuum when the temperature is lower than the predetermined temperature. By controlling the drive time of the drive means so as to reduce the amount of decompression by shortening the operation time of the pump, the decompression storage chamber is controlled so as not to become below a certain pressure .

  In addition, pressure detecting means for detecting the pressure in the decompression storage chamber is provided, and when the vacuum pump is in a driving state, the pressure detection means detects a predetermined pressure in the decompression storage chamber and stops the vacuum pump after a predetermined time has elapsed. It is characterized by making it.

  A motor that drives the vacuum pump; and a current detection unit that detects a current of the motor. When the current detection unit detects a current lower than a predetermined value while the vacuum pump is driven, The vacuum pump is stopped after a lapse of time.

  ADVANTAGE OF THE INVENTION According to this invention, the refrigerator which was provided with the decompression storage chamber and improved the reliability of decompression operation can be obtained.

It is a front view of the refrigerator of one embodiment of the present invention. It is AA sectional drawing of the refrigerator of FIG. It is a control block diagram in this embodiment. It is a figure which shows the relationship between the pressure change of a decompression storage chamber, and the drive of a vacuum pump. It is an operation | movement chart figure of a pressure switch. It is a basic control flowchart figure of pressure reduction operation. It is a basic control flowchart figure in the case of continuing a pressure reduction state. It is a flowchart figure of pressure reduction operation | movement which has temperature determination in a pressure reduction storage chamber. It is a pressure reduction operation | movement flowchart which changes pressure reduction time in steps according to the temperature in a pressure reduction storage chamber. It is a figure explaining the drive time of a vacuum pump.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a front view of a refrigerator main body 1 according to an embodiment of the present invention. In the refrigerator main body 1, a refrigerator compartment 7, ice making rooms 8 provided on the left and right, a first freezer compartment 9, a second freezer compartment 10, and a vegetable compartment 11 are arranged in order from the top. The refrigerator compartment 7 and the vegetable compartment 11 are storage compartments in a refrigerated temperature zone, and the ice making compartment 8, the first freezer compartment 9 and the second freezer compartment 10 have a freezing temperature zone of 0 ° C. or less (for example, about −20 ° C. to −18 ° C. This is a storage room in the temperature zone. Reference numeral 12 denotes an operation panel, which is installed on the refrigerator compartment door 2.

  On the front surface of the refrigerator body 1, there are a refrigerator door 2 that closes the front opening of the refrigerator compartment 7, an ice making door 3 that closes the front opening of the ice making chamber 8, and a front opening of the first freezer compartment 9. The first freezer compartment door 4 for closing, the second freezer compartment door 5 for closing the front opening of the second freezer compartment 10, and the vegetable compartment door 6 for closing the front opening of the vegetable compartment 11. Each has it.

  The refrigerator compartment door 2 is composed of a double door that is a left-right opening type, that is, a French door. The refrigerator compartment 7 is provided with a refrigerator compartment door switch 13 for detecting opening and closing of the refrigerator compartment door 2.

  The ice making room door 3, the first freezing room door 4, the second freezing room door 5, and the vegetable room door 6 are constituted by a drawer-type door, and a container in the storage room is pulled out together with the drawer door.

  FIG. 2 is a cross-sectional conceptual diagram taken along line AA in FIG. A decompression storage chamber 15 is installed in the lowermost space 14 in the refrigerator compartment 7. The decompression storage chamber 15 is connected to a vacuum pump 16 which is an example of decompression means by a conduit 17 and is configured to decompress. The refrigerator compartment 7 is provided with a pressure switch 22 for detecting the pressure in the decompression storage compartment 15.

  A vacuum storage chamber door 18 that opens and closes an opening for taking in and out food is provided on the front surface of the vacuum storage chamber 15.

  In the above configuration, an embodiment in which the decompression storage chamber 15 is decompressed will be described with reference to FIGS.

  FIG. 3 is a control block diagram. In FIG. 3, 20 is a refrigerator temperature sensor that is a means for detecting the temperature in the refrigerator compartment 7, 21 is a vacuum storage chamber temperature sensor that is a means for detecting the temperature in the vacuum storage room 15, and 19 is a control means. A microcomputer 12a indicates display LEDs incorporated in the operation panel 12, respectively. Further, detection signals from the refrigerator compartment door switch 13 and the refrigerator compartment temperature sensor 20 are respectively input to the microcomputer 19 and output signals are output to the vacuum pump 16 based on the control specifications described later.

  Next, the pressure reduction performance when the vacuum pump 16 is operated is shown in FIG. The horizontal axis represents time, the vertical axis represents the pressure state in the decompression storage chamber 15 and the operation / stop state of the vacuum pump 16, the open / close state of the refrigerator door 2, the temperature state of the decompression storage chamber 15, the state of the pressure switch 22, and the vacuum The operating current of the pump 16 is shown. In this embodiment, the pressure value is a gauge pressure, and the unit is represented by kPa · G. Therefore, atmospheric pressure = 0 kPa · G, and a negative value at a lower pressure than that.

  As shown in FIG. 4, when the operation of the vacuum pump 16 is started, the pressure gradually decreases with time, and reaches a reduced pressure target pressure (about −20 kPa · G). After the pressure is reduced to −20 kPa · G, the low pressure state is maintained unless the decompression storage chamber door 18 is opened. However, the space between the vacuum pump 16, the conduit 17, and the decompression storage chamber 15 is not a completely sealed structure and is very small. Air leaks.

  Further, in the case of using the vacuum pump 16 having the same suction capability, when the volume of the decompression storage chamber 15 is different, that is, when the amount of air to be sucked is different, the speed at which the pressure decreases as the volume decreases is proportionally faster. It is considered to be. Similarly, regarding air leakage from the decompression storage chamber 15, it is considered that the speed at which the pressure increases as the substantial volume decreases. Below, the example of the air leak by the difference in volume is shown.

<When a 10L container is decompressed to -20kPa · G (2L intake)>
Pressure when 0.5 L of air leaks after 5 hours ... -15kPa · G
<When a container with a substantial volume of 5 L is depressurized to -20 kPa · G (1 L intake)>
Pressure when 0.5 L of air leaks after 5 hours ... -10kPa · G

  As described above, the speed of decompression and the speed of air leakage vary depending on the volume of the decompression storage chamber 15, but the pressure in the decompression storage chamber 15 is controlled by performing the control described below using the pressure switch 22. Can be kept constant. Since the pressure switch 22 is inexpensive, the pressure switch 22 is turned off when the pressure is lower than −10 kPa · G and turned on when the pressure is higher than −10 kPa · G, as shown in FIG. The detection value is one point.

  Next, FIG. 6 is a basic control flowchart of the vacuum pump when performing a pressure reducing operation, and it is assumed that the pressure in the pressure reducing storage chamber 15 is around 0 kPa · G at the start of control (step S1).

  After the start of control (step S1), the open / close state of the refrigerator compartment door 2 is determined in step S2. If the refrigerator compartment door 2 is closed, the process proceeds to step S5. If the refrigerator compartment door 2 is kept closed for a predetermined time A, the process proceeds to step S6.

  If the refrigerator compartment 2 is opened in step S2, the time A is cleared in step S3, and the vacuum pump 16 is stopped (step S4, refer to FIG. 4 as appropriate).

  When the pressure switch 22 is off (at a pressure lower than −10 kPa · G) in step S6, the operation of the vacuum pump 16 is stopped (step S11), and the operation ends. When the pressure switch 22 is on (higher than −10 kPa · G) in step S6, the state of the refrigerator compartment door 2 is confirmed in step S7.

  If the refrigerator compartment door 2 is "open" in step S7, it returns to step S3 and repeats the above-mentioned operation | movement. On the other hand, if the refrigerator compartment door 2 is “closed” in step S7, the vacuum pump 16 is operated until the pressure switch 22 is turned off (steps S8 and S9), and the process proceeds to step S10.

  In step S10, after the pressure switch 22 is turned off, the vacuum pump 16 is operated for B hours, and then the vacuum pump 16 is stopped in step S11 (see FIG. 4 as appropriate).

  The purpose of confirming the opening / closing of the refrigerator compartment door 2 in step S7 is to prevent the user from becoming harsh when the user opens the refrigerator compartment door 2 because an operating noise is generated during operation of the vacuum pump 16.

  The reason for providing the monitoring time A in step S5 is to prevent the number of operations of the vacuum pump 16 from increasing when the refrigerator compartment door 2 is frequently opened and closed in a short time.

  As described above, after reaching −20 kPa · G, the low pressure state is basically maintained unless the user opens the decompression storage chamber door 18. However, it is not easy to make the space between the vacuum pump 16, the conduit 17, and the decompression storage chamber 15 completely sealed, and minute air leakage occurs. As shown in FIG. 4, if air leaks from the outside to the inside of the decompression storage chamber 15, the pressure gradually increases and eventually returns to 0 kPa · G.

  The purpose of decompressing the decompression storage chamber 15 is to preserve the stored food for a long period of time by maintaining the storage space in a low oxygen state. That is, before reaching the vicinity of 0 kPa · G, it is necessary to operate the vacuum pump 16 again to maintain the reduced pressure state. Therefore, even after the pressure is reduced to −20 kPa · G, it is necessary to reduce the pressure by operating the vacuum pump 16 again depending on the state of the pressure switch 22.

  Therefore, a pressure reducing operation for maintaining a low pressure is performed in the basic control flowchart shown in FIG. In this flowchart, it is assumed that the pressure state at the start of control (step S13) is in the vicinity of −20 kPa · G and that the refrigerator compartment door 2 is “closed”.

  After step S13, after the pressure switch 22 is turned on (higher than −10 kPa · G) in step S14, the process proceeds to step S16 after the elapse of C time (step S15) (see FIG. 4 as appropriate).

  If the refrigerator compartment door 2 is "open" in step S16, it will progress to step S19 and will not operate | move but the operation | movement will be complete | finished (step S20).

  On the other hand, if the refrigerator compartment door 2 is “closed” in step S16, the vacuum pump 16 is operated for D hours (step S18; refer to FIG. 4 as appropriate), the vacuum pump 16 is stopped in step S19, and the operation ends ( Step S20).

  The purpose of providing C time until the start of operation of the vacuum pump 16 in step S15 is that the vacuum pump 16 is operated even when it is momentarily turned on, such as when the pressure switch 22 is vibrated. This is to prevent it.

  By the above operation, the pressure switch 22 detects an air leak in the decompression storage chamber 15 and operates the vacuum pump 16 again, whereby the pressure in the decompression storage chamber 15 can be kept at a certain level or less.

  By using the basic control of the decompression operation shown in FIG. 6 and the low pressure holding control shown in FIG. 7, the pressure in the decompression storage chamber 15 can be kept below a certain pressure.

  However, the pressure in the sealed container advances as the temperature decreases. Therefore, there is a possibility that the pressure becomes lower than the desired pressure. As described above, the space between the vacuum pump 16, the conduit 17, and the decompression storage chamber 15 is not a completely sealed space but air leakage occurs. However, this air leakage is basically a minute amount unless dust adheres between the decompression storage chamber 15 and the decompression storage chamber door 18.

  As an example, if no air leak occurs, the pressure in the vacuum storage chamber 15 is reduced to −20 kPa · G, and then the pressure in the vacuum storage chamber 15 is reduced by 40 ° C., the pressure is reduced to about −30 kPa · G. descend. Here, if the target pressure is −20 kPa · G and the durability of the decompression storage chamber 15 is set to −25 kPa · G, the decompression storage chamber 15 may be damaged.

  In order to prevent damage to the decompression storage chamber 15, the strength of the decompression storage chamber 15 is increased to improve durability, and a desired pressure (−20 kPa · G in this embodiment) is provided by providing a valve for pressure adjustment. ) It is possible to construct a system that does not become the following. However, the addition of the pressure regulating valve causes air leakage from the connection part. Moreover, the pressure regulating valve is expensive.

  Therefore, in order to construct a low-cost and highly reliable system, the decompression storage chamber temperature sensor 21 provided in the decompression storage chamber 15 is used to control the inside of the decompression storage chamber 15 so as not to be below a certain pressure. This will be described with reference to the flowchart of FIG. As a premise, the durability of the decompression storage chamber 15 is set to a limit value of −25 kPa · G.

  Steps S21 to S26 are the same as the basic control of the decompression operation described above, but in step S27, it is determined whether the temperature in the decompression storage chamber 15 is the upper limit value of the vacuum pump operating temperature (less than 40 ° C), and 40 ° C or more. If it is, the vacuum pump 16 is not operated, and if it is less than 40 degrees, the process proceeds to step S28.

  If it is determined in step S28 that the inside of the decompression storage chamber 15 is “low temperature”, the vacuum pump 16 is operated for a time (B time) for decompressing to −20 kPa · G, as in the basic control of the decompression operation described above. The operation ends (steps S29 to 32, 37, 38).

  Assuming that the temperature in the refrigerator compartment is finally 0 ° C., a maximum temperature difference of about 20 ° C. will occur, but even if there is no air leakage at this time, the pressure in the vacuum storage chamber 15 is the lowest. Up to -25 kPa · G.

  In step S28, when the inside of the decompression storage chamber 15 is determined to be “high temperature”, the basic operation is the same as that for the “low temperature” determination, but the vacuum pump operation time (E time) is different.

  When the temperature in the decompression operation is 40 ° C. at the maximum, a temperature difference of 40 ° C. occurs when the temperature in the refrigerator compartment decreases to 0 ° C. Accordingly, the time E is set to a time during which the pressure is reduced to a pressure not lower than -25 kPa · G even when a temperature difference of 40 ° C. occurs. That is, the relationship is set so as to satisfy the relationship of B time> E time, and the pressure reduction amount is controlled to be smaller than when the temperature is lower than the predetermined temperature.

  For example, the operation time of the vacuum pump 16 required for reducing the pressure in the vacuum storage chamber 15 to −15 kPa · G is defined as E time. That is, even after the pressure is reduced to −15 kPa · G and the temperature in the reduced pressure storage chamber 15 is lowered by 40 ° C., the pressure drop is suppressed to about −25 kPa · G.

  By the above control, it is possible to prevent the pressure from being lower than a certain pressure without using excessive reinforcement of the decompression storage chamber 15 or a pressure regulating valve, and to realize a low-cost and highly reliable system. it can.

  In addition, when the temperature of the refrigerator compartment 7 which installed the decompression storage chamber 15 is detected by the refrigerator compartment temperature sensor 20, and the vacuum pump 16 is controlled based on this detected temperature, the same effect can be show | played. This is because the decompression storage chamber 15 is installed in the refrigerator compartment 7 and is indirectly cooled, so that the temperature change is substantially the same. In this case, the decompression storage chamber temperature sensor 21 can be deleted to reduce the number of parts.

  Further, when a current detection unit that detects a current of a motor that drives the vacuum pump 16 is detected and the current detection unit detects a current lower than a predetermined value while the vacuum pump is driven, the vacuum pump 16 is passed after a predetermined time has elapsed. Stop. This predetermined value is set between the current value detected at atmospheric pressure and the lock current value of the motor. Thereby, the reliability of pressure reduction operation can be improved.

  In the first embodiment, the method of changing the operation time of the vacuum pump 16 depending on whether the temperature of the decompression storage chamber 15 or the refrigerator compartment 7 during the decompression operation is “low temperature” or “high temperature” has been described.

  In the present embodiment, a pressure control method in which the operation time of the vacuum pump 16 is changed stepwise depending on the temperature of the decompression storage chamber 15 to prevent the pressure from becoming lower than a desired pressure will be described with reference to the flowchart of FIG. Here, it is assumed that the temperature at which the decompression storage chamber 15 is cooled and finally reached is t ° C., and the vacuum pump operation time at t ° C. is F time.

  The basic operation of this control is the same as the basic control of the decompression operation shown in FIG. 1, but the operation time (G time) of the vacuum pump 16 is determined by the temperature of the decompression storage chamber.

  When a predetermined pressure is detected in step S43 and the pressure switch is turned on, the decompression storage chamber temperature T is stored in step S44. In step S44, a temperature correction value α for determining G time is set using the decompression storage chamber temperature T (step S45). Here, the temperature correction value α is calculated by α = (T−t) × β using the coefficient β.

  Next, the operation time (G time) of the vacuum pump 16 is set in step S46. The G time is G time = F time−α.

  Here, if the coefficient β is a positive value, α increases as the decompression storage chamber temperature T increases, and decreases as the decompression storage chamber temperature T decreases. Therefore, the G time satisfies G time <F time in the range of T> t, and G time> F time in the range of T <t.

  FIG. 10 illustrates an actual operation in this control with a specific example. Here, t = 0 ° C., β = 1.5, F time = 60 seconds, the reduced pressure storage chamber temperature T is constant at 0 ° C., and the reduced pressure storage chamber 15 is reduced from 20 ° C. to 0 ° C. The state will be described.

<When T = 0 ° C is constant>
When T = 0, (T−t) = 0 and the temperature correction value α is 0, so that G time = F time = 60 seconds. When the time (H time) until the pressure switch 22 is turned off is 60 seconds, the operation time of the vacuum pump 16 is 120 seconds in total, and at this time, the pressure in the decompression storage chamber 15 becomes −20 kPa · G.

<When T decreases from 20 ° C to 0 ° C>
When T = 20 ° C., (T−t) = 30 and the correction value α is 30, so that G time = 60−30 = 30 seconds. Similarly, if the H time is 60 seconds, the operation time of the vacuum pump 16 is 90 seconds in total, and the pressure in the decompression storage chamber 15 at this time is −15 kPa · G.

  After the pressure is reduced to −15 kPa · G, the pressure in the vacuum storage chamber is reduced to 0 ° C., so the pressure in the vacuum storage chamber is reduced to about −20 kPa · G.

  By the above control, by setting the coefficient β and F time according to the performance of the vacuum pump 16 and the temperature zone where the decompression storage chamber 15 is installed, the internal pressure can be changed even if the temperature of the decompression storage chamber 15 changes. Can be prevented from becoming lower than a certain pressure.

DESCRIPTION OF SYMBOLS 1 Refrigerator body 2 Refrigeration room door 3 Ice making room door 4 First freezing room door 5 Second freezing room door 6 Vegetable room door 7 Refrigerating room 8 Ice making room 9 First freezing room 10 Second freezing room 11 Vegetable room 12 Operation panel 13 Refrigeration room door switch 14 Lowermost space 15 Decompression storage room 16 Vacuum pump (decompression means)
17 Conduit 18 Decompression chamber door 19 Microcomputer 20 Cold room temperature sensor 21 Depressurization chamber temperature sensor 22 Pressure switch

Claims (3)

A decompression storage room provided in the refrigerator body;
Decompression means which is a vacuum pump for decompressing the decompression storage chamber ;
Reduced pressure storage chamber temperature detection means for detecting the temperature of the reduced pressure storage chamber;
Control means for controlling the stopping and stopping of the decompression means,
When the temperature detected by the reduced pressure storage chamber temperature detecting means is equal to or higher than a predetermined temperature, the control means shortens the operation time of the vacuum pump and reduces the amount of reduced pressure as compared with a case where the temperature is lower than the predetermined temperature. The refrigerator characterized by controlling the said decompression storage chamber so that it may not become below a fixed pressure by controlling the drive time of a drive means . A pressure detecting means for detecting a pressure of the vacuum storage compartment, after a predetermined time the vacuum pump is the pressure detecting means in a driving state is detected a predetermined pressure of the vacuum storage compartment, Ru to stop the vacuum pump The refrigerator according to claim 1, wherein A motor that drives the vacuum pump; and a current detection unit that detects a current of the motor. When the current detection unit detects a current lower than a predetermined value while the vacuum pump is driven, a predetermined time has elapsed. after, characterized Rukoto to stop the vacuum pump, a refrigerator according to claim 1.

Images