JP2006038314A - Stirling refrigerating machine, and cooler mounted therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a Stirling refrigerating machine, and a cooler mounted therewith capable of continuing operation while securing safety even when there is a failure in either one of a temperature sensor of a heat exchange part for heat dissipation, or a temperature sensor of a heat exchange part for heat absorption. <P>SOLUTION: The cooler is provided with the low temperature side temperature sensor measuring a temperature of the heat exchange part for heat absorption, the high temperature side temperature sensor measuring a temperature of the heat exchange part for heat dissipation, and a controller inputted with each of low temperature side temperature information measured by the low temperature side temperature sensor and high temperature side temperature information measured by the high temperature side temperature sensor, and controlling a piston. When at least one piece of information from the low temperature side temperature information or the high temperature side temperature information is abnormal information other than predetermined information, the controller drives the piston such that a refrigerating capacity becomes a predetermined value or less as emergency operation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a Stirling refrigerator and a refrigerator in which the Stirling refrigerator is mounted.

  Commercialization of a refrigerator (freezer, refrigerator / freezer) equipped with a Stirling refrigerator has been studied. In the Stirling refrigerator, a temperature sensor is provided in each of the heat exchange part for heat dissipation and the heat exchange part for heat absorption. The controller of the refrigerator controls the operation of the Stirling refrigerator based on the temperature information of these temperature sensors. If any of these temperature sensors fails, Stirling is ensured. Stop the refrigerator.

In the present specification, the term “cooling” is used as a concept including both freezing and refrigeration. That is, the refrigerator refers to all devices that bring the space to be cooled to a temperature lower than the outside air. The refrigerator includes a refrigerator-freezer. A refrigerator-freezer is a refrigerator having both a freezer that freezes an object and a refrigerator that does not freeze the object but maintains the space around the object at a temperature lower than the outside air.
JP 2000-18747 A

  However, in the above refrigerator, the operation of the Stirling refrigerator is stopped if any one of the temperature sensor of the heat exchange part for heat dissipation and the temperature sensor of the heat exchange part for heat absorption breaks down. The user is forced into an inconvenient state.

  The present invention has been made in view of the above-described problems, and its purpose is to provide safety even when one of the temperature sensor of the heat-dissipating heat exchange part and the temperature sensor of the heat-absorbing heat exchange part fails. It is to provide a Stirling refrigerator capable of continuing operation while ensuring the performance and a refrigerator equipped with the Stirling refrigerator.

  A Stirling refrigerator according to one aspect of the present invention includes a piston that reciprocates in a cylinder, a displacer that reciprocates in a state having a predetermined phase difference from the reciprocating motion of the piston, and a reciprocating motion of the piston and a reciprocating motion of the displacer. An expansion space in which the refrigerant expands, a heat absorption heat exchange portion to which the cold generated in the expansion space is transmitted, a low temperature sensor for measuring the temperature of the heat absorption heat exchange portion, a reciprocating motion of the piston and a displacer A compression space in which the refrigerant is compressed by reciprocating motion, a heat exchange part for heat radiation to which the heat generated in the compression space is transmitted, a high temperature side temperature sensor for measuring the temperature of the heat exchange part for heat radiation, and a low temperature side temperature sensor Each of the low temperature side temperature information measured by the high temperature side temperature information measured by the high temperature side temperature sensor is input, And a control device for controlling the piston. When at least one of the low temperature side temperature information and the high temperature side temperature information is abnormal information outside of a predetermined temperature range, the control device performs piston operation so that the refrigeration capacity becomes a predetermined value or less as an emergency operation. Drive.

  According to the above configuration, even if an abnormality occurs in at least one of the low temperature side temperature sensor and the high temperature side temperature sensor, the operation of the Stirling refrigerator is continued while ensuring the safety of the operation of the Stirling refrigerator. can do.

  Further, when the emergency operation is performed, the control device may execute ON / OFF control of the Stirling refrigerator as well as inverter control for reducing the stroke of the piston. According to this configuration, the emergency operation can be executed with simple control.

  Further, the Stirling refrigerator is connected to the high temperature side secondary refrigerant circulation pipe that receives the heat obtained in the heat radiating heat exchanger and circulates the received heat by the secondary refrigerant, and the high temperature side secondary refrigerant circulation pipe. It is desirable to further include a radiator and a blowing device that is controlled by the control device and promotes heat exchange of the radiator by blowing. In addition, when the emergency operation is being performed, the control device desirably drives the blower with a higher blowing capacity than that of the blower before the emergency operation. According to this configuration, when the emergency operation is performed, it is possible to reduce the probability of occurrence of a problem due to an increase in the outside allowable temperature of the heat radiating heat exchanging unit.

  A Stirling refrigerator according to another aspect of the present invention includes a piston that reciprocates in a cylinder, a displacer that reciprocates in a state in which the reciprocating motion of the piston has a predetermined phase difference, and a reciprocating motion of the piston and a reciprocating motion of the displacer. An expansion space in which the refrigerant expands, a heat absorption heat exchange portion to which the cold generated in the expansion space is transmitted, a low temperature sensor for measuring the temperature of the heat absorption heat exchange portion, a reciprocating motion of the piston and a displacer A compression space in which the refrigerant is compressed by reciprocating motion, a heat exchange part for heat radiation to which the heat generated in the compression space is transmitted, a high temperature side temperature sensor for measuring the temperature of the heat exchange part for heat radiation, and a low temperature side temperature sensor Each of the low temperature side temperature information measured by the high temperature side temperature information measured by the high temperature side temperature sensor is input, And a control device for controlling the piston. In addition, when one of the low temperature side temperature information and the high temperature side temperature information is abnormal information outside a predetermined temperature range, the control device can detect the other of the low temperature side temperature information and the high temperature side temperature information. Using this information, substitute information for one piece of information that is abnormal information is created, and the piston is controlled using the substitute information.

  According to the above configuration, the normal operation of the Stirling refrigerator can be continued even when either one of the low temperature side temperature information and the high temperature side temperature information is out of order.

  The refrigerator according to one aspect of the present invention includes the Stirling refrigerator according to one aspect described above and a cooling space that is cooled by using the cold generated in the heat-absorbing heat exchange unit of the Stirling refrigerator. The cooling space is provided with an internal temperature sensor that measures the temperature of the cooling space. Moreover, the internal temperature information measured by the internal temperature sensor is input to the control device. In addition, the control device includes a first control for controlling the Stirling refrigerator so that the temperature of the cooling space based on the internal temperature information falls within a predetermined temperature range, and the temperature of the cooling space based on the internal temperature information is within the predetermined temperature range. The second control for controlling the Stirling refrigerator can be executed so as to fall within a lower specific temperature range. Furthermore, the control device performs the first control operation when the emergency operation is performed while the second control is being performed.

  According to said structure, the driving | operation which a piston reciprocates with a small stroke is performed so that a Stirling refrigerator may not exhibit big freezing capacity. As a result, the Stirling refrigerator is prevented from being damaged by the operation in the abnormal temperature state.

  A refrigerator according to another aspect of the present invention includes the Stirling refrigerator according to one aspect described above and a cooling space that is cooled using the cold generated in the heat-absorbing heat exchange unit of the Stirling refrigerator. The refrigerator further includes a heater. The control device controls the driving of the heater and stops the driving of the heater when an emergency operation is performed.

  According to said structure, since the drive of a heater is stopped at the time of emergency operation, when the refrigerating capacity of a Stirling refrigerator becomes small, the raise of the temperature of cooling space can be suppressed even a little.

  A refrigerator according to still another aspect of the present invention includes the Stirling refrigerator according to one aspect described above and a cooling space that is cooled using the cold generated in the heat-absorbing heat exchanger of the Stirling refrigerator. The refrigerator further includes an ice making machine and a control device that controls driving of the ice making machine. Further, the control device stops the driving of the ice making machine when the emergency operation is performed.

  According to said structure, when the refrigerating capacity of a Stirling refrigerator becomes small at the time of emergency operation, the refrigerating capacity required for ice making can be cut and the temperature rise of a cooling space can be suppressed even a little.

(Embodiment 1)
First, the Stirling refrigerator used for the refrigerator of the embodiment will be described.

  Drawing 1 is a sectional view showing Stirling refrigerator 40 of an embodiment. In the Stirling refrigerator 40, a cylindrical piston 1 and a displacer 2 are fitted in a cylindrical cylinder 3 composed of two parts. The piston 1 and the displacer 2 are provided via a compression space 9 and have an axis Y as a common drive shaft.

  An expansion space 10 is formed on the tip side of the displacer 2. The compression space 9 and the expansion space 10 communicate with each other via a medium flow passage 11 through which a working medium such as helium flows. A regenerator 12 is provided in the medium flow path 11. The regenerator 12 accumulates the heat of the working medium and supplies the accumulated heat to the working medium. A flange (flange) 3 a is provided in the middle of the cylinder 3. A bounce space (back space) 8 is formed in the flange portion 3a by being sealed with a dome-shaped pressure vessel 4 attached thereto.

  The piston 1 is integrated with the support spring 5 on the rear end side. The displacer 2 is integrated with the support spring 6 through a rod 2 a that passes through the center hole 1 a of the piston 1. The support spring 5 and the support spring 6 are connected by a bolt and a nut 22. As will be described later, when the piston 1 reciprocates, the displacer 2 reciprocates in a state having a predetermined phase difference with respect to the piston 1 due to a pressure difference acting on both end faces thereof.

  An inner yoke 18 is fitted on the outer side of the cylinder 3 in the bounce space 8. The outer yoke 17 is opposed to the inner yoke 18 through a gap 19. A driving coil 16 is fitted inside the outer yoke 17. An annular permanent magnet 15 is movably provided in the gap 19. The permanent magnet 15 is integrated with the piston 1 through a cup-shaped sleeve 14. The inner yoke 18, the outer yoke 17, the driving coil 16, and the permanent magnet 15 constitute a linear motor 13 that moves the piston 1 along the axis Y.

  Lead wires 20 and 21 are connected to the driving coil 16. The lead wires 20 and 21 pass through the wall surface of the pressure vessel 4 and are connected to the control device 30. Driving power is supplied to the linear motor 13 by the control device 30.

  In the Stirling refrigerator 40 having the above configuration, when the piston 1 reciprocates by the linear motor 13, the displacer 2 reciprocates with a predetermined phase difference with respect to the piston 1. As a result, the working medium moves between the compression space 9 and the expansion space 10. As a result, a reverse Stirling cycle is formed.

  FIG. 2 is a diagram illustrating a state of electrical connection between the control device 30 and the Stirling refrigerator 40. On the outer surface of the Stirling refrigerator 40, a temperature sensor 34 that detects the temperature Tc of the expansion space 10, a temperature sensor 35 that detects the temperature Th of the compression space 9, and a temperature sensor 36 that detects the temperature Tb of the bounce space 8. Is attached.

  The control device 30 includes a TcA / D converter 108 that converts the output information of the temperature sensor 34 from analog information to digital information, a ThA / D converter 109 that converts the output information of the temperature sensor 35 from analog information to digital information, A TbA / D conversion unit 110 that converts output information of the temperature sensor 36 from analog information to digital information is provided. Further, a voltage output unit 101 for driving a linear motor is connected to the hermetic seal terminal 37 via lead wires 20 and 21. The linear motor driving voltage output unit 101 outputs the driving voltage of the linear motor 13.

  Further, the control device 30 is connected to the above-described devices that control heaters 1000 and 1400, a damper 2000, and an ice making machine 3000, which will be described later, by signal lines for transmitting control signals.

  FIG. 3 is a block diagram showing further details of the control device 30. The control device 30 is provided with a microcomputer 104 that performs various calculations. A power supply unit 105 that supplies power to each unit of the control device 30 is connected to the microcomputer 104.

  A voltage value input unit 102 is connected to the microcomputer 104. The voltage value input unit 102 receives the detection value of a voltage sensor (not shown) that detects the input voltage of the power supply unit 105 in a state converted from analog information to digital information. Further, the microcomputer 104 is connected to a current value input unit 103 to which the detection value of the current sensor 33 that detects the current of the linear motor 13 is input after conversion from analog information to digital information. Further, the memory includes a reset unit 106 that resets the control device 30, an oscillation unit 107 that generates a PWM (Pulse Width Modulation) inverter waveform, and a rewritable nonvolatile storage element (EEPROM). The unit 111 is connected to the microcomputer 104.

  The storage unit 111 stores the relationship between the input voltage and the refrigeration output corresponding to at least each Stirling refrigerator 40. In the free piston type Stirling refrigerator 40 as shown in FIG. 1, the displacer 2 reciprocates due to pressure fluctuations in the compression space 9 and the expansion space 10 based on the reciprocation of the piston 1. Therefore, the amount of movement of the displacer 2 with respect to the input voltage tends to vary for each Stirling refrigerator 40 due to a change in the flow resistance of the refrigerant passing through the medium flow passage 11. The fact that this variation occurs means that the refrigeration output of the Stirling refrigerator differs even when a constant input voltage is applied to each of the plurality of Stirling refrigerators. Therefore, in order to accurately control the output of each Stirling refrigerator, the relationship between the input voltage and the refrigeration output corresponding to the Stirling refrigerator is calculated as numerical data, and the digitized data is stored in the storage unit 111. Let Thereby, the microcomputer 104 controls the voltage output from the linear motor driving voltage output unit 101 using the digitized data indicating the above-described relationship.

  As will be described later, a control signal is transmitted from the microcomputer 104 to the power supply unit 105 in accordance with data input from the voltage value input unit 102 to the microcomputer 104. Thereby, the output voltage of the power supply unit 105 is controlled. The linear motor driving voltage output unit 101 converts the output voltage of the power source unit 105 into a PWM inverter waveform under the control of the microcomputer 104 and supplies the converted voltage of the PWM inverter waveform to the linear motor 13.

  During normal operation, the microcomputer 104 drives heaters 1000 and 1400 and an ice making machine 3000, which will be described later, and outputs a control signal for opening the damper 2000. However, during emergency operation, which will be described later, the heaters 1000, 1400. In addition, the driving of the ice making machine 3000 is stopped, and a control signal for closing the damper 2000 is output.

  FIG. 4 is a block diagram showing an internal configuration of the microcomputer 104. In the microcomputer 104, a read-only ROM 121 in which a control program is stored, a RAM 122 that temporarily stores operations, a timer 123 that measures an operation time, and an I / O port 125 for input / output are connected to the CPU 124. ing. The Stirling refrigerator 40 is controlled by the CPU 124 executing the control program read from the ROM 121.

  In the Stirling refrigerator 40 of the above-described embodiment, when a drive voltage having a predetermined AC waveform is applied to the linear motor 13, the piston 1 reciprocates at a cycle and a stroke corresponding to the drive voltage having the predetermined AC waveform. . Therefore, it is possible to control the cycle and stroke of the reciprocating motion of the piston 1 by controlling the drive voltage applied to the linear motor 13.

  Next, the operation principle of the free piston type Stirling refrigerator of the present embodiment will be described in more detail.

  The piston 1 is driven by a linear motor 13. The piston 1 is elastically supported by the support spring 5. Therefore, the piston 1 moves so that the relationship between its position and time draws a sine wave.

  Further, due to the movement of the piston 1, the working gas in the compression space 9 moves so that the relationship between the pressure and time draws a sine wave. The working gas compressed in the compression space 9 first releases heat from the compression space 9 as a heat exchange part for heat dissipation. Next, the compressed working gas is cooled by a regenerator 12 provided around the displacer 2. Thereafter, the compressed working gas flows from the regenerator 12 into the expansion space 5 as a heat exchange part for heat absorption.

  The working gas in the expansion space 5 is expanded by the movement of the displacer 2. The temperature of the expanded working gas decreases. The working gas in the expansion space 5 moves so that the relationship between the pressure and time draws a sine wave. The sine wave indicating the relationship between the pressure of the working gas in the expansion space 5 and time is a waveform having a predetermined phase difference with respect to the sine wave indicating the relationship between the pressure of the working gas in the compression space 9 and time. There is a waveform that changes with the same period. That is, the displacer 2 reciprocates with a predetermined phase difference with respect to the piston 1.

The refrigeration capacity in the expansion space 5 is determined by the degree of fluctuation in the pressure of the working gas in the expansion space 10 caused by the reciprocating motion of the displacer 2. The pressure in the expansion space 10 is a relative position between the displacer 2 and the piston 1 caused by a change between the phase of the piston 1 and the phase of the displacer 2, that is, the difference between the pressure in the expansion space 10 and the pressure in the compression space 9. Fluctuates due to changes in

  The relative positional relationship between the displacer 2 and the piston 1 is determined by the mass of the displacer 2, the spring constant of the support spring 6, and the frequency of the piston 1. Further, the mass of the displacer 2 and the spring constant of the support spring 6 are determined at the time of design, and cannot be changed during operation.

  Therefore, in the Stirling refrigerator 40 of the present embodiment, the control device 30 that outputs the inverter waveform shown in FIG. 3 (the current sensor 33 is incorporated therein) and the heat absorption of the Stirling refrigerator 40. A thermistor circuit (Tc thermistor) for measuring the temperature of the expansion space 10 as a heat exchanging part, a thermistor circuit (Th thermistor) for measuring the temperature of the compression space 9 as a heat exchanging part and a bounce space And a thermistor circuit (Tb thermistor) for measuring the temperature of 8.

  In the present embodiment and each embodiment described later, the microcomputer 104 in the control device 30 includes a TcA / D converter 108, a ThA / D converter 109, and a TbA / D converter 110, respectively. The linear motor driving voltage output unit 101 outputs a driving voltage for driving the piston 1 by using the information of each thermistor circuit obtained through the above, the information of the current sensor 33, the voltage measuring circuit 112, and the like.

  The voltage waveform output from the microcomputer 104 is a digital signal, that is, a pulse waveform. This pulse waveform is converted into an analog signal, that is, a sine wave in the linear motor driving voltage output unit 101. The frequency of this sine wave becomes the frequency of the piston 1 of the Stirling refrigerator 40.

  Note that when converting a digital signal to an analog signal, PWM is used as described above. That is, the plurality of pulses sequentially output from the microcomputer 104 gradually change in width from a small one to a large one, and after returning to a peak width, gradually return to a small one. It is configured. Thereby, an AC waveform is generated.

  Hereinafter, the refrigerator of the present embodiment will be described with reference to the drawings.

  FIG. 5 is a schematic cross-sectional view of a refrigerator equipped with a free piston type Stirling refrigerator. As shown in FIG. 5, the refrigerator includes a cooling space 116 in which an object to be cooled is stored, and a Stirling refrigerator 40 for lowering the temperature in the cooling space 116.

  An evaporator 130 is provided in the cooling space 116. The evaporator 130 and the heat exchange part for heat absorption of the Stirling refrigerator 40 (the expansion space 10 described above) are connected by a low temperature side secondary refrigerant pipe 200. Therefore, the cold heat in the expansion space is transmitted to the evaporator 130 by the secondary refrigerant (for example, carbon dioxide) flowing in the low temperature side secondary refrigerant pipe 200. The evaporator 130 transmits the cold heat conveyed by the secondary refrigerant to the cooling space 116. The transmission of this cold heat is promoted by the cooling fan 120.

In the vicinity of the Stirling refrigerator 40, Th-side heat radiation fins 113 are provided. The heat-dissipating heat exchange part (the aforementioned compression space 9) of the Stirling refrigerator 40 and the Th-side heat radiation fin 113 are connected by a high-temperature side secondary refrigerant pipe 300. The heat of the compression space 9 is transmitted to the Th-side heat radiation fin 113 by a secondary refrigerant (for example, water) that flows through the high-temperature side secondary refrigerant pipe 300. The Th-side heat radiation fin 113 discharges the heat transported by the secondary refrigerant to the outside of the cooler 100. The effect | action which this Th side radiation fin 113 discharge | releases warm heat is accelerated | stimulated by the thermal radiation apparatus 119. FIG.

  A temperature sensor 34 that measures the temperature Tc of the heat-absorbing heat exchange part (expansion space 10) of the Stirling refrigerator 40, and a temperature sensor that measures the temperature Th of the heat-dissipation heat exchange part (compression space 9) of the Stirling refrigerator 40 35 is the same as described above. An internal temperature sensor 117 that measures the temperature Tk of the cooling space 116 is attached to the inner wall of the cooling chamber that constitutes the cooling space 116. A signal indicating the temperature Tk detected by the internal temperature sensor 117 is transmitted to the TkA / D converter 170 in the control device 30 as shown in FIG.

  As shown in FIG. 5, when the refrigerator 100 of the present embodiment is operating, the following operation occurs.

  The value of the temperature Tc of the heat absorption heat exchange unit measured by the temperature sensor 34 and the value of the temperature Th of the heat exchange heat exchange unit measured by the temperature sensor 35 are transmitted to the control device 30. The cold heat of the heat absorption heat exchange part of the Stirling refrigerator 40 is transmitted to the evaporator 130 by carbon dioxide flowing through the low temperature side secondary refrigerant pipe 200. Cold heat is transmitted to the air in the cooling space 116 by the evaporator 130. This cold heat convects in the cooling space 116 by the function of the cooling fan 120. The value of the temperature Tk of the cold air in the cooling space 116 measured by the internal temperature sensor 117 is transmitted to the control device 30.

  The heat of the heat radiating heat exchange part of the Stirling refrigerator 40 is transmitted to the heat radiating fins 113 by water (water vapor) flowing through the high temperature side secondary refrigerant pipe 300. The heat generated in the radiating fins 113 is exhausted to the outside of the cooler 100 by a radiating device (blower: fan, etc.) 119.

  As shown in FIG. 6, the refrigerator of the present embodiment includes a refrigerator compartment 800, a freezer compartment 700, and an ice making compartment 900 as cooling spaces. A secondary refrigerant pipe 1200 is connected to the heat exchange part (cold head) for heat absorption of the Stirling refrigerator 40, and a secondary refrigerant such as carbon dioxide circulates in the secondary refrigerant pipe 1200. . The secondary refrigerant pipe 1200 is a circulation circuit, and one end thereof is connected to the evaporator 1100. In the evaporator 1100, the cold heat of the secondary side refrigerant flowing through the secondary side refrigerant pipe 1200 is transmitted, and outside, the cold air rises through the duct 1300 as indicated by arrows in the drawing. Openings are provided in various places of the duct 1300, and cold air is sent to the refrigerator compartment 800, the freezer compartment 700, and the ice making compartment 900.

  In addition, a damper is provided in each opening that communicates each of the refrigerator compartment 800 and the freezer compartment 700 with the duct 1300, although not shown. In addition, a damper 2000 is provided in an opening that communicates the ice making chamber 900 and the duct 1300. When the cold air for making ice in the ice making chamber 900 is not introduced into the ice making chamber 900, the damper 2000 provided at the duct opening connected to the ice making chamber 900 is closed. Moreover, the evaporating dish 600 to which the defrost water of the evaporator 1100 is guided is provided at the lowermost part of the refrigerator. In the evaporating dish 600, defrost water is collected and evaporated by the heat of the heater 1400.

  A heater 1000 is provided in the heat insulation wall between the refrigerator compartment 800 and the freezer compartment 700. The heater 1000 is for preventing condensation from being generated on the bottom surface of the refrigerator compartment 800 when the cold heat of the freezer compartment 700 is transmitted to the refrigerator compartment 800. Therefore, the heater 1000 is turned off during emergency operation. Further, the heater 1400 provided in the evaporating dish 600 is also turned off during the emergency operation. Further, during the emergency operation, since the cool air led to the ice making chamber 900 is not necessary, the damper 2000 provided at the opening of the duct 1300 led to the ice making chamber 900 is closed, and a new ice making operation of the ice making machine 3000 is performed. Absent. The ice making operation means an operation of a pump or a valve for supplying water to an ice making device. Therefore, an ice making machine refers to equipment used for ice making such as a pump or a valve for supplying water to an ice making machine. Also, the stop of the ice making machine means the stop of these devices.

  Next, the emergency operation determination process performed in the control device 30 of the refrigerator according to the present embodiment will be described with reference to FIG.

  In the emergency operation determination process of the refrigerator of the present embodiment, first, normal operation is executed in S1. Next, in S2, the temperature Tc of the temperature sensor 34 and the value of Th of the temperature sensor 35 are acquired. That is, the value of each temperature of the heat exchange part for heat dissipation and the heat exchange part for heat absorption is acquired. Next, in S3, it is determined whether or not the value of the temperature Tc of the heat-absorbing heat exchange part is within a predetermined range. In S3, if the value of temperature Tc is not within the predetermined range, control device 30 determines that an abnormality has occurred in temperature sensor 34 of the heat-absorbing heat exchange unit, and performs an emergency operation in S5.

  In S3, if the value of temperature Tc is within the predetermined range, control device 30 determines that temperature sensor 34 is functioning normally, and in S4, the value of temperature Th is within the predetermined range. It is determined whether or not there is. If the temperature Th is not within the predetermined range in S4, the control device 30 determines that an abnormality has occurred in the temperature sensor 35, and an emergency operation is executed in S5. If the value of temperature Th is within the predetermined range in S4, control device 30 determines that both temperature sensor 34 and temperature sensor 35 are functioning normally, and performs emergency operation without performing emergency operation. The driving determination process ends.

  According to the emergency operation determination process of the refrigerator of the present embodiment, in S3 and S4, at least one of the temperature of the heat dissipation heat exchange part and the temperature of the heat absorption heat exchange part is within a predetermined range. If not, that is, if it is determined that there is a failure in the temperature sensors provided in the heat absorption heat exchange section and the heat radiation heat exchange section, emergency operation is performed in S5. That is, the emergency operation is performed when at least one of the temperature sensor 34 and the temperature sensor 35 is out of order.

  Next, the operation mode performed in the emergency operation will be described with reference to Table 1.

  As shown in Table 1, during normal operation, the heat radiating fan rotation speed of the heat radiating device 119 is a small value, but during emergency operation, the rotation speed of the heat radiating fan is higher than during normal operation. As a result, even if the temperature of the heat exchanging part for heat dissipation is abnormally high, the rotational speed of the heat dissipating fan is increased, so that the efficiency of heat exchange is increased, and the Stirling refrigerator is damaged. Is prevented.

  In addition, each of the heater 1400 and the heater 1000 that are operating during normal operation is stopped during the emergency operation. That is, since each of the heaters 1400 and 1000 is not necessarily required to maintain the state of the object to be cooled such as food in the refrigerator compartment 800 and the freezer compartment 700, the control device 30 does not require the respective heaters 1400 and 1000. By stopping the operation, an operation for reducing the burden on the Stirling refrigerator 40 as much as possible is executed. Further, during emergency operation, a damper provided at an opening of a duct connected to the ice making chamber 900 is closed and new ice making operation of the ice making machine 3000 (including an ice making pump or a valve) is prohibited (ice making machine 3000). Stop operation). That is, at the time of emergency operation, the control device 30 determines that it is not necessary to make ice, cuts off the cool air introduced into the ice making chamber 900, and prohibits new ice making operation, so that the refrigerating room 800 and the refrigeration are as small as possible. The cooling capacity required for ice making is cut by allowing cold air to flow through the chamber 700, thereby reducing the burden on the Stirling refrigerator 40.

  Further, during normal operation, the Stirling refrigerator 40 is controlled so as to change according to the loads of the refrigerator compartment 800 and the freezer compartment 700, but during emergency operation, the refrigeration output is smaller than that during normal operation. Driving is done. For example, control for minimizing the stroke of the piston 1 is executed. The smaller the stroke of the piston 1, the smaller the refrigeration capacity of the Stirling refrigerator 40. Therefore, at the time of emergency operation, by reducing the refrigeration capacity of the Stirling refrigerator 40 than at the time of normal operation, the temperature of the heat absorption heat exchange unit becomes too low, and the temperature of the heat dissipation heat exchange unit becomes too high. It is prevented. This prevents the Stirling refrigerator 40 from being damaged.

  Further, instead of setting the stroke value of the piston 1 to the minimum value, the stroke of the piston 1 is set to a predetermined value slightly smaller than that during normal operation, and the ON period of the ON / OFF control of the Stirling refrigerator 40 is set to a predetermined time. Such control may be executed. This also makes it possible to make the refrigeration capacity of the Stirling refrigerator 40 smaller during emergency operation than during normal operation.

  In addition, the control of the stroke of the piston 1 is not changed as described above, but the control is performed to change the target temperature value of the internal temperature sensor 117 provided in the internal storage to a value higher than that during normal operation. May be. According to this control, the output of the Stirling refrigerator 40 is controlled so that the temperature of the internal temperature sensor 117 is higher than that during normal operation. That is, control is performed such that the stroke of the piston 1 is smaller than that during normal operation.

  According to the control during the emergency operation as described above, since the output of the Stirling refrigerator 40 is smaller than that during the normal operation, the temperature sensor 35 of the heat dissipation heat exchange unit and the temperature sensor of the heat absorption heat exchange unit are assumed. Even if at least one of 34 is out of order, the Stirling refrigerator 40 is not operated in an abnormal temperature state, so that the possibility of damage to the Stirling refrigerator is reduced.

(Embodiment 2)
Next, an emergency operation control process performed in the control device 30 of the Stirling refrigerator of the second embodiment will be described with reference to FIG.

  Note that the refrigerator of the present embodiment is exactly the same as the refrigerator and the Stirling refrigerator of the first embodiment with respect to the control, the refrigerator, and the entire configuration of the Stirling refrigerator other than the emergency operation control process described below. It is.

  In the emergency operation control process of the present embodiment, normal operation is first executed in S11. Next, in S12, the values of the temperature Tc of the temperature sensor 34 and the temperature Th of the temperature sensor 35 are acquired. Next, in S13, it is determined whether or not the value of the temperature Tc is within a predetermined range. In S13, if the value of temperature Tc is within a predetermined range, control device 30 determines that temperature sensor 34 is functioning normally, and in S14, whether the value of temperature Th is within the predetermined range. It is determined whether or not. In S14, if the value of the temperature Th is within the predetermined range, both the temperature sensor 35 of the heat-dissipating heat exchange unit and the temperature sensor 34 of the heat-absorbing heat exchanging unit are functioning normally. The normal operation of S11 is continued without performing the operation.

  In S14, if the value of the temperature Th is not within the predetermined range, the control device 30 determines that the temperature sensor 35 of the heat-dissipating heat exchange unit is out of order. Using the value of the temperature Tc of the temperature sensor 34, the value of the temperature Th of the temperature sensor 35 of the heat exchange part for heat dissipation is predicted. Using the value of the temperature Th calculated by this prediction, the normal operation is continued in S11 as in the case where the temperature sensor 35 of the heat exchange unit for heat radiation has not failed.

  In S13, if the value of temperature Tc is not within the predetermined range, control device 30 determines that temperature sensor 34 has failed, and in S16, whether the value of temperature Th is within the predetermined range. It is determined whether or not. In S16, if the value of the temperature Th is not within the predetermined range, both the temperature sensor 35 of the heat-dissipating heat exchanging unit and the temperature sensor 34 of the heat-absorbing heat exchanging unit have failed. It is determined that it is necessary to stop the operation of the Stirling refrigerator 40, and in S18, the operation of the Stirling refrigerator 40 and all other devices is stopped and a failure is displayed. Further, in S16, if the value of the temperature Th is within a predetermined range, the temperature sensor 34 of the heat absorption heat exchange unit is out of order, but the temperature sensor 35 of the heat dissipation heat exchange unit is out of order. In S17, the value of the temperature Tc of the temperature sensor 34 of the heat absorption heat exchange unit is calculated using the value of the temperature Th of the temperature sensor of the heat exchange unit for heat dissipation. Thereby, the normal operation is continued in S11 as in the case where the value of the temperature Tc of the temperature sensor 34 of the heat exchange part for heat absorption is normally obtained.

  According to the emergency operation control process of the present embodiment as described above, when either one of the temperature sensor 35 of the heat exchange part for heat radiation and the temperature sensor 34 of the heat exchange part for heat absorption is defective. By predicting the temperature value of one of the temperature sensors using the temperature value of the other temperature sensor, both the temperature sensor 35 of the heat exchange part for heat dissipation and the temperature sensor 34 of the heat exchange part for heat absorption are normal. Control processing during emergency operation is performed as if it is functioning.

  However, in order to predict the temperature value of the malfunctioning temperature sensor as in the present embodiment, the temperature value of the temperature sensor 34 of the heat-absorbing heat exchange unit obtained in advance by experiment, The correspondence relationship with the temperature value of the temperature sensor 35 of the replacement unit needs to be stored in the data table. In addition, the control device 30 needs to execute control for deriving the value of the other temperature sensor by referring to the data table using the value of one of the temperature sensors at the time of failure.

  According to the control method of the refrigerator in this embodiment, when one of the two temperature sensors is broken, it is as if using the value of the other temperature sensor that is not broken. Normal operation can be continued as if both temperature sensors are functioning normally.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing which shows the structure of the Stirling refrigerator of embodiment. It is a figure for demonstrating the relationship between the linear motor of the Stirling refrigerator of embodiment, and a control apparatus. It is a figure for demonstrating the internal structure of the control apparatus of the Stirling refrigerator of embodiment. It is a figure for demonstrating the inside of the microcomputer of the Stirling refrigerator of embodiment. It is a schematic diagram of arrangement | positioning of each apparatus when the freezer of embodiment is seen from the upper side. It is a schematic diagram of the longitudinal cross-section of the refrigerator of embodiment. 4 is a flowchart for explaining an emergency operation determination process according to the first embodiment. 6 is a flowchart for illustrating emergency operation control processing according to the second embodiment.

Explanation of symbols

  130 evaporator, 113 Th-side heat radiation fin, 119 heat radiation device, 120 cooling fan, 30 control device, 34, 35 temperature sensor, 40 Stirling refrigerator, 116 cooling space, 117 internal temperature sensor.

Claims (6)

A piston that reciprocates in the cylinder;
A displacer that reciprocates in a state having a predetermined phase difference from the reciprocating motion of the piston;
An expansion space in which the refrigerant expands due to the reciprocating motion of the piston and the reciprocating motion of the displacer;
An endothermic heat exchanging part to which the cold generated in the expansion space is transmitted;
A low temperature side temperature sensor for measuring the temperature of the heat exchange part for heat absorption; and
A compression space in which the refrigerant is compressed by the reciprocating motion of the piston and the reciprocating motion of the displacer;
A heat exchange part for heat dissipation to which the heat generated in the compression space is transmitted;
A high temperature side temperature sensor for measuring the temperature of the heat exchange part for heat radiation;
Each of the low temperature side temperature information measured by the low temperature side temperature sensor and the high temperature side temperature information measured by the high temperature side temperature sensor is input, and includes a control device for controlling the piston,
When at least one of the low temperature side temperature information and the high temperature side temperature information is abnormal information outside a predetermined range, the control device is configured so that the refrigeration capacity becomes a predetermined value or less as an emergency operation. A Stirling refrigerator that drives the piston. A high-temperature-side secondary refrigerant circulation pipe that receives the heat obtained in the heat-dissipating heat exchange section and circulates the received heat using a secondary refrigerant;
A radiator connected to the high-temperature side secondary refrigerant circulation pipe;
Further comprising a blower controlled by the control device and promoting heat exchange of the radiator by blowing.
2. The Stirling refrigerator according to claim 1, wherein, when the emergency operation is performed, the control device drives the air blower with a blower capacity higher than that of the blower apparatus before the emergency operation is performed. . A piston that reciprocates in the cylinder;
A displacer that reciprocates in a state having a predetermined phase difference from the reciprocating motion of the piston;
An expansion space in which the refrigerant expands due to the reciprocating motion of the piston and the reciprocating motion of the displacer;
An endothermic heat exchanging part to which the cold generated in the expansion space is transmitted;
A low temperature side temperature sensor for measuring the temperature of the heat exchange part for heat absorption; and
A compression space in which the refrigerant is compressed by the reciprocating motion of the piston and the reciprocating motion of the displacer;
A heat exchange part for heat dissipation to which the heat generated in the compression space is transmitted;
A high temperature side temperature sensor for measuring the temperature of the heat exchange part for heat radiation;
Each of the low temperature side temperature information measured by the low temperature side temperature sensor and the high temperature side temperature information measured by the high temperature side temperature sensor is input, and includes a control device for controlling the piston,
When one of the low temperature side temperature information and the high temperature side temperature information is abnormal information outside a predetermined range, the control device includes the low temperature side temperature information and the high temperature side temperature information. A Stirling refrigerator that creates substitute information for the one piece of information that is the abnormality information using the other piece of information and controls the piston using the substitute information. A refrigerator having the Stirling refrigerator according to claim 1 and a cooling space cooled by using the cold generated in the heat absorption heat exchange section of the Stirling refrigerator,
The cooling space is provided with an internal temperature sensor for measuring the temperature of the cooling space,
The internal temperature information measured by the internal temperature sensor is input to the control device,
The controller is
A first control for controlling the Stirling refrigerator so that the temperature of the cooling space based on the internal temperature information falls within a predetermined temperature range;
The second control for controlling the Stirling refrigerator can be executed so that the temperature of the cooling space based on the internal temperature information falls within a specific temperature range lower than the predetermined temperature range,
Further, the control device is a refrigerator that performs the operation of the first control when the emergency operation is performed while the second control is being performed. A refrigerator having the Stirling refrigerator according to claim 1 and a cooling space cooled by using the cold generated in the heat absorption heat exchange section of the Stirling refrigerator,
The refrigerator further includes a heater,
The control device controls the drive of the heater and stops the drive of the heater when the emergency operation is performed. A refrigerator having the Stirling refrigerator according to claim 1 and a cooling space cooled by using the cold generated in the heat absorption heat exchange section of the Stirling refrigerator,
The refrigerator further includes an ice maker,
The control device controls the driving of the ice making machine and stops the driving of the ice making machine when the emergency operation is performed.

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