JP2004177119A - Cold storage, and motor-operated valve for refrigeration cycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make quiet (silent) a noise generated from a motor-operated valve as a selector valve. <P>SOLUTION: A liquid coolant acts as a cushioning material to reduce the generation noise in initialization, because the initialization for a motor-operated three-way valve 20 is executed after the coolant is made to flow inside the three-way valve 20 under a liquid condition by operating a compressor 17. The generation noise in the initialization is eliminated by an operation noise of a cold storage chamber fan 11 or a refrigerating chamber fan 15, and an operation noise of the compressor 17, because the fan 11 or 15, and a compressor cooling fan 18 are driven together with the driving of the compressor 17. A switching operation for the three-way valve 20 is executed also after the coolant is made to flow inside the three-way valve 20 under the liquid condition. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to a refrigerator provided with a switching valve that switches the flow of a refrigerant so that the refrigerant flows selectively through a plurality of refrigerant channels, and an electric valve for a refrigeration cycle that switches a refrigerant channel of a refrigeration cycle.

  Equipment equipped with a refrigeration cycle, such as a refrigerator, is generally installed indoors, especially in a living space, and is therefore required to have a low noise level. The noise during the operation of the refrigerator has been reduced due to the use of a refrigerator.

  However, in a refrigerator provided with a switching valve for switching the flow of the refrigerant, the sound generated from the switching valve may sound unpleasant or unusual, which has been a problem. For example, a solenoid valve often used as a switching valve includes a valve element provided in a valve body via an urging means, and a solenoid for generating a magnetic force for moving the valve element against the urging force of the urging means. When a drive voltage is applied to the solenoid, the valve element is sucked by the suction element in a short time. Therefore, the valve body vigorously collides with the suction element, and at this time, a loud collision sound (switching sound) is generated.

  In order to reduce the switching noise, there is a switching valve that uses an electric valve instead of an electromagnetic valve. In this electric valve, a motor and a valve portion are combined, and a valve element provided in a valve body moves as a rotor of the motor rotates to open and close a valve hole (port). It is configured.

  When an electric valve is used, the position of the valve body can be controlled by controlling the rotation of the motor, so that collision of the valve body can be suppressed and the switching noise of the valve can be reduced. However, even with this motor-operated valve, a sliding sound (for example, 25 to 40 dB (A) at a distance of 10 cm from the motor-operated valve) is generated at the time of switching. Reduction was desired.

  On the other hand, when an electric valve employing a stepping motor, for example, is used as the motor, the control device performs open-loop control on the position of the valve element (or rotor) for the stepping motor. A deviation may occur between the commanded body position and the actual position. In addition, when the power is turned on or when the power is restored from a power failure (including an instantaneous power failure), the position of the valve body is unknown.

Therefore, when using a motor-operated valve, a position initialization operation (so-called initialization) for moving the position of the valve body to the initial position is generally required. In the case of a refrigerator, initialization is performed at a rate of, for example, once every two to three days, for example, when power is turned on, when power is restored after a power failure, and when power is restored.
In this position initialization operation, the control device performs sufficient motor driving to return to the initial position even when the valve element is at the position farthest from the initial position. In the above-described stepping motor type electric valve, the control device gives a sufficient number of drive pulses for the valve element to return.

  A stopper is provided in the valve body to restrict the valve body from moving beyond the initial position. When the initialization is performed, a hitting sound is generated by an impact of the valve body hitting the stopper. This hitting sound continues to occur intermittently until the rotation of the motor stops after the valve body reaches the initial position and hits the stopper, and when the fixture for the electric valve is made of a thin iron plate, Sound may also be generated from the fixture. Since this generated sound may be heard as an abnormal sound by a refrigerator user, soundproof measures such as surrounding the motor-operated valve with a soundproofing material are required.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a refrigerator in which noise generated from a motor-operated valve as a switching valve is reduced (silenced), and noise reduction (silence reduction) is provided. An object of the present invention is to provide a refrigeration cycle motor-operated valve.

In order to achieve the above object, a refrigerator according to the present invention described in claim 1 includes a compressor, a condenser for liquefying a refrigerant discharged from the compressor, and a plurality of refrigerants liquefied by the condenser. In a refrigerator provided with a switching valve for switching the flow of the refrigerant so as to selectively circulate the refrigerant flow path, and control means for controlling the operation of the switching valve,
The switching valve is a motor-operated valve comprising a motor and a valve unit configured to move a valve body in a valve body based on an initial position as a rotor of the motor rotates, The valve unit includes a position regulating unit that restricts the valve body from moving beyond the initial position, and the control unit operates the compressor in a state where the refrigerant flows through the refrigerant passage. After a predetermined time has elapsed since the start of the operation, only when liquid refrigerant is present in the valve body of the switching valve, a position initialization operation of moving the valve body to the initial position is performed. It is characterized by having been done.

  According to this configuration, when the control means starts the position initialization operation, the valve body in the valve body starts moving toward the initial position, and when the valve body reaches the initial position, the valve body hits the position regulating means and stops moving. I do. The control means performs the position initializing operation when the liquid refrigerant exists in the valve body of the switching valve, so that the liquid refrigerant acts as a buffer for the movement of the valve element. As a result, it is possible to reduce the hitting sound generated when the valve body hits the position regulating means (silent effect).

  Further, since the position initialization operation is performed after a predetermined time has elapsed from the start of operation of the compressor in a state where the refrigerant is circulated in the refrigerant flow path, the position initialization operation is started. At this time, the refrigerant has already been sufficiently compressed by the compressor, and the liquid refrigerant flows downstream of the condenser, so that the hitting noise generated by the position initialization operation can be reduced. Further, since the hitting sound generated is masked by the operation sound of the compressor, it is difficult for the user to recognize it as an abnormal sound.

  Further, in the refrigerator according to the present invention described in claim 2, the control means is configured to perform the switching operation of the switching valve only when a liquid refrigerant exists in the valve body of the switching valve. It is characterized by the following. According to this configuration, at the time of movement of the valve element due to rotation of the rotor of the motor, the mixed liquid of the refrigerant and the refrigerating machine oil enters the sliding portion such as between the valve element and the valve seat, and the lubricating film is there. Is formed, the sliding noise is reduced (silent effect).

  In addition, since the switching operation is performed after a predetermined time has elapsed from the start of operation of the compressor in a state where the refrigerant is circulated in the refrigerant flow path, the compressor is sufficiently compressed by the compressor. Since the switching operation is performed in a state where the liquid refrigerant flows on the downstream side of the condenser, the sliding noise is reduced. Further, since the generated sliding noise is masked by the operating noise of the compressor, it is difficult for the user to recognize the sliding noise as abnormal noise.

  In the above case, the refrigerant flow path is provided with a refrigerator cooler that cools the refrigerator and a freezer cooler that cools the freezer, and the plurality of refrigerant flow paths mainly contain the refrigerant in the refrigerator cooler. A first refrigerant flow path for supplying refrigerant to the freezer compartment cooler, and a second refrigerant flow path for mainly supplying refrigerant to the freezer compartment cooler. It is preferable to use an electric three-way valve that selectively circulates through the second refrigerant passage (claim 3).

  According to this configuration, when the electric three-way valve serving as the switching valve is switched to the first refrigerant flow path side, the refrigerant is mainly supplied to the refrigerator compartment cooler to cool the refrigerator compartment, and the electric three-way valve is switched to the first refrigerant passage. When the refrigerant is switched to the second refrigerant flow path side, the refrigerant is mainly supplied to the freezer compartment cooler to cool the freezer compartment.

The refrigerator according to the present invention described in claim 4 includes a compressor, a condenser, and a switching valve that switches a flow of the refrigerant so as to selectively flow the refrigerant liquefied by the condenser to the plurality of refrigerant flow paths. Control means for controlling the operation of the switching valve, a cooler provided in the refrigerant flow path, an in-compartment cooling fan for sending cool air generated by the cooler into the compartment, and the compressor A refrigerator having a compressor cooling fan for cooling,
The switching valve is an electric valve having the above-described configuration, and the valve unit includes a position regulating unit that restricts movement of the valve body beyond the initial position. The control unit includes the compressor cooling fan. It is configured to perform a position initializing operation of moving the valve body to the initial position only during the operation of (1).

  According to this configuration, the contact sound generated when the valve body moves to the initial position by the position initialization operation and hits the position regulating means is masked by the operation sound (for example, wind noise) of the compressor cooling fan, that is, the background noise. This makes it difficult for the user to recognize the hit sound as harsh or unusual sound (silence effect).

  In the above configuration, during operation of the compressor cooling fan, after a predetermined time has elapsed since the compressor started operating in a state in which the refrigerant is allowed to flow through the refrigerant flow path, the inside of the valve body of the switching valve is changed. It is preferable that the control means be configured to perform the position initialization operation when the liquid refrigerant exists in the liquid crystal panel. According to this configuration, since the above-described silent operation by the liquid refrigerant and the silencing operation by the operation sound of the compressor cooling fan are obtained, the hitting sound can be further suppressed.

  In this case, the control means may be configured to perform the position initialization operation after the operation state of the compressor cooling fan is stabilized (claim 6). According to this configuration, since the position initialization operation is performed after the operation state of the fan is stabilized, that is, after the operation sound (for example, wind noise) of the fan is increased, the masking effect of the hitting sound is increased. The silencing effect on the hit sound appears more.

  The refrigerator according to the present invention described in claim 7 is characterized in that the control means is configured to perform the switching operation of the switching valve only during the operation of the compressor cooling fan. According to this configuration, the sliding noise generated when the valve element is moved is masked by the operating noise (for example, wind noise) of the compressor cooling fan, so that a silencing effect can be obtained.

  In the above configuration, during operation of the compressor cooling fan, after a predetermined time has elapsed since the compressor started operating in a state in which the refrigerant is allowed to flow through the refrigerant flow path, the inside of the valve body of the switching valve is changed. Preferably, the control means is configured to perform the switching operation only when the liquid refrigerant is present in the liquid crystal. According to this configuration, in addition to the silencing effect due to the fan operating noise, the silencing effect of the sliding noise due to the formation of the lubricating film is obtained, so that the noise generated from the switching valve can be further suppressed.

In this case, the control means may be configured to perform the switching operation after the operation state of the compressor cooling fan is stabilized (claim 9). According to this configuration, the masking effect of the sliding sound is increased, and the noise-eliminating effect on the sliding sound is more pronounced.
Further, when the switching valve is operated during operation of the compressor cooling fan, the switching valve is, as described above, an electric three-way valve that causes the refrigerant to flow through the first refrigerant flow path or the second refrigerant flow path. Is preferable (claim 10). According to this configuration, by switching the flow of the refrigerant by the electric three-way valve, it is possible to perform cooling of the refrigerator compartment and cooling of the freezer compartment.
In the above case, the motor of the switching valve may be a stepping motor. According to this configuration, by applying a predetermined number of drive pulses to the motor, the rotor rotates by an angle substantially proportional to the number of pulses. Therefore, the position control of the valve body becomes easy.

In order to achieve the above object, an electric valve for a refrigeration cycle according to the present invention described in claim 12 is provided in a refrigerant flow path of a refrigeration cycle including a compressor, and a valve body in a valve body is set at an initial position. A valve unit configured to open and close the refrigerant flow path by being moved as a reference, a motor that moves a valve body of the valve unit with rotation of a rotor, and a motor provided in the valve unit, Position regulating means for restricting movement of the valve body beyond the initial position, and provided so as to control the operation of the valve body via the motor, so that the refrigerant flows through the refrigerant flow path. A control for executing a position initialization operation of moving the valve body to the initial position only when a liquid refrigerant is present in the valve body after a predetermined time has elapsed after the compressor started operating in a state. And means are provided. That.
According to this configuration, the liquid refrigerant acts as a cushioning material with respect to the movement of the valve element due to the position initialization operation, so that the hitting sound generated when the valve element hits the position regulating means is reduced.

  Further, after a predetermined time has elapsed from the start of the operation of the compressor in a state where the refrigerant is allowed to flow through the refrigerant flow path, the valve body is closed only when a liquid refrigerant exists in the valve body. Preferably, the control means is configured to execute an operation of moving (claim 13). According to this configuration, the mixed liquid of the refrigerant and the refrigerating machine oil enters the sliding portion, and a lubricating film is formed there, so that sliding noise is reduced.

Further, the control means may be configured to execute a position initialization operation of moving the valve body to the initial position only during operation of a blower fan that blows air to a compressor or a condenser of a refrigeration cycle. . According to this configuration, the contact sound between the valve body and the position regulating means is masked by the operation sound of the blower fan (for example, wind noise).
Furthermore, it is preferable that the control means is configured to execute the operation of moving the valve body only during the operation of the blower fan that blows air to the compressor or the condenser of the refrigeration cycle (claim 15). According to this configuration, the sliding noise is masked by the operation sound of the blower fan (for example, the wind noise).

  The control means of the electric valve for the refrigerator and the refrigeration cycle of the present invention is configured such that after a predetermined time elapses from the start of operation of the compressor with the refrigerant flowing through the refrigerant flow path, the valve body of the electric valve is Since the position initialization operation of moving the valve body to the initial position is performed only when the liquid refrigerant is present, the liquid refrigerant acts as a buffer for the movement of the valve body, and the position initialization operation is performed. A silent sound effect in which the generated hit sound is suppressed to a small level is obtained.

  In addition, after a predetermined time has elapsed from the start of operation of the compressor in a state where the control unit controls the refrigerant to flow through the refrigerant flow path, a liquid refrigerant exists in the valve body of the electric valve. Since the switching operation of the motor-operated valve is performed only at the time, the mixed liquid of the refrigerant and the refrigerating machine oil enters the sliding portion, and a lubricating film is formed there, thereby reducing the sliding noise.

  Further, the control means is configured to perform the position initialization operation or the switching operation only during the operation of the compressor cooling fan (during the operation of the blower fan). A noise reduction effect is obtained in which the sliding noise generated by the operation is masked by the operation noise of the compressor cooling fan (blowing fan).

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 actually shows a schematic configuration of the refrigerator main body 1 and the refrigeration cycle 2. In FIG. 1, the refrigerator main body 1 is constituted by a heat insulating box, and the inside thereof is partitioned by a heat insulating partition wall 3 into an upper refrigerator compartment 4 and a lower freezer compartment 5. In the refrigerating compartment 4, a first cooler compartment 7 is formed by a partition wall 6 at a deep portion thereof, and a vegetable compartment 9 is formed by a partition wall 8 at a lower portion thereof. A refrigerator 10 for the refrigerator compartment of the refrigeration cycle 2 is provided in a lower part of the first cooler room 7. An outlet 6a is formed in the upper part of the partition wall 6, and a refrigerator compartment fan 11 (corresponding to an in-compartment cooling fan according to the present invention) is disposed in the outlet 6a. In addition, a suction port 6b for communicating the first cooler room 7 and the vegetable room 9 is formed at a lower portion of the partition wall 6, and a communication for communicating the refrigeration room 4 and the vegetable room 9 to the partition wall 8. The mouth 8a is formed.

  On the other hand, in the freezer compartment 5, a second cooler compartment 13 is formed by a partition wall 12 at the back portion thereof, and a cooling portion for the freezer compartment of the refrigerating cycle 2 is provided in a lower portion inside the cooler compartment 13. A vessel 14 is provided. An outlet 12a is formed in an upper portion of the partition wall 12, and a freezing room fan 15 (corresponding to an in-compartment cooling fan in the present invention) is disposed in the outlet 12a. In addition, a suction port 12 b that connects the second cooler room 13 and the freezing room 5 is formed in a lower portion of the partition wall 12. A machine room 16 is formed at the lower part of the refrigerator main body 1, and a compressor 17 of the refrigeration cycle 2 and a compressor cooling unit for cooling the compressor 17 are provided at the back of the machine room 16. A fan 18 is provided.

  The refrigeration cycle 2 includes a condenser 19, an electric three-way valve 20, which is a switching valve, and capillary tubes 21a and 21b, in addition to the refrigerator cooler 10, the refrigerator cooler 14, and the compressor 17. In this case, a discharge port of the compressor 17 is connected to an inlet of the electric three-way valve 20 via a refrigerant flow pipe 22 provided with a condenser 19, and a first outlet of the electric three-way valve 20 is a capillary tube 21a. The refrigerator 17 is connected to the suction port of the compressor 17 through the refrigerator 10, the connecting pipe 23, and the refrigerator 14. The second outlet of the electric three-way valve 20 communicates with a portion of the connecting pipe 23 via the capillary tube 21b.

  In the refrigeration cycle 2 as described above, the electric three-way valve 20 performs the first operation of the refrigerant discharged from the compressor 17 and condensed and liquefied by the condenser 19 via the refrigerator cooler 10 and the refrigerator cooler 14. The switching is performed so as to selectively flow through either the refrigerant flow path or the second refrigerant flow path via only the freezer compartment cooler 14. In the following description, a state in which the electric three-way valve 20 is switched so that the refrigerant flows through the first refrigerant flow path is referred to as a refrigeration compartment cooling mode. The state where the three-way valve 20 is switched is referred to as a freezing room cooling mode.

  According to the above configuration, in the operating state of the compressor 17, the refrigerant compressed by the compressor 17 is liquefied by the condenser 19 and then supplied to the electric three-way valve 20. At this time, when the electric three-way valve 20 has been switched to the freezer compartment cooling mode, the refrigerant is supplied only to the freezer compartment cooler 14 via the capillary tube 21b, and the freezer compartment cooling is performed. After the evaporator 14 evaporates, it returns to the compressor 17. In such a state, the freezer compartment fan 15 operates. Due to the blowing action of the freezing room fan 15, the cool air from the freezing room cooler 14 is supplied into the freezing room 5 from the second cooler room 13 through the outlet 12a as shown by an arrow F in FIG. After that, the cooling chamber 13 returns to the cooler room 13 through the suction port 12b, whereby the cooling operation in the freezing room 5 is performed.

  Further, when the electric three-way valve 20 is switched to the refrigerator compartment cooling mode in the operation state of the compressor 17, the refrigerant discharged from the compressor 17 and liquefied through the condenser 19 is supplied to the capillary tube 21a. Are supplied to the refrigerator cooler 10 and the refrigerator cooler 14 in this order. At this time, the amount of the liquid refrigerant mainly evaporates in the refrigerator compartment cooler 10 and then a relatively small amount of liquid refrigerant that could not be evaporated here evaporates in the refrigerator compartment cooler 14. It returns to the compressor 17 after the evaporation.

  In such a state, the refrigerator compartment fan 11 operates. Due to the blowing action of the refrigerator compartment fan 11, the cool air from the refrigerator compartment cooler 10 is supplied into the refrigerator compartment 4 from the first cooler compartment 7 through the outlet 6a as shown by an arrow R in FIG. After that, it flows into the vegetable compartment 9 through the communication port 8a, and then returns to the cooler room 7 through the suction port 6b, whereby the cooling operation of the refrigerator compartment 4 and the vegetable compartment 9 is performed.

  FIG. 2 shows a schematic electrical configuration of the refrigerator 1 including the refrigeration cycle 2 by combining functional blocks. That is, in FIG. 2, the refrigerator compartment temperature sensor 24 and the freezer compartment temperature sensor 25 detect the temperature inside the refrigerator compartment 4 and the temperature inside the freezer compartment 5, respectively, and are constituted by, for example, a thermistor. The refrigerator cooler temperature sensor 26 and the freezer cooler temperature sensor 27 detect the temperatures of the refrigerator cooler 10 and the freezer cooler 14, respectively, and are composed of, for example, a thermistor. . These temperature sensors 24, 25, 26, 27 are connected to input terminals of a control device 28 (corresponding to control means in the present invention) mainly composed of a microcomputer.

  An output terminal of the control device 28 includes an inverter 29 for driving the compressor motor 17a, an inverter 30 for driving the refrigerator compartment fan motor 11a, an inverter 31 for driving the freezer compartment fan motor 15a, and a compressor. A drive circuit 32 for driving the machine cooling fan motor 18a and a drive circuit 33 for driving the electric three-way valve 20 (a stepping motor to be described later) to rotate forward or reverse are connected.

  The controller 28 sets the refrigerator compartment upper limit set temperature (for example, 5 ° C.) and the refrigerator compartment lower limit set temperature (for example, 2 ° C.) for the temperature of the refrigerator compartment 4, and sets the freezer compartment upper limit for the temperature of the refrigerator compartment 5. The temperature (for example, −18 ° C.) and the lower limit temperature of the freezer compartment (for example, −21 ° C.) are set. Then, the control device 28 sets the respective temperatures of the refrigerator compartment 4 and the freezer compartment 5 to fall within the upper and lower limit set temperature ranges based on the set temperatures and the input signals from the temperature sensors 24 to 27, respectively. In this way, the control of the drive of the compressor motor 17a, the fan motor 11a for the refrigerator compartment, the fan motor 15a for the freezer compartment, the fan motor 18a for the compressor cooler, and the operation of the electric three-way valve 20 are controlled in accordance with the control program stored in advance. It has become.

Subsequently, the electric three-way valve 20 will be described with reference to FIG. 3 which is a longitudinal sectional view and FIG. 4 which is a bottom view.
The electric three-way valve 20 is configured by combining an inner rotor type stepping motor 34 and a valve portion 35. The stator 36 of the stepping motor 34 is provided with a stator winding 37 wound in an annular shape, and a cylindrical case 38 made of a non-magnetic material is fitted inside the stator winding 37. The upper end of the case 38 is hermetically closed by an end plate 39, and a cylindrical valve body 40 having a slightly larger diameter than the case 38 is attached to the lower end of the case 38. Further, a disc-shaped valve seat 41 is fitted into the lower end portion of the valve body 40 from below, and plasma welding is performed.

  Inside the case 38, a rotor 42 formed in a cup shape is disposed at a position facing the stator winding 37 with the case 38 interposed therebetween. The rotor 42 is multipolarly magnetized, and a rotating shaft 43 is fixedly inserted through an axis of the rotor 42. The upper end of the rotating shaft 43 is supported by a bearing 39 a provided on the end plate 39 via a compression coil spring 44, and the lower end of the rotating shaft 43 is extended downward by a joint 45 by a joint 45. Pins 46 are connected. The lower end of the pin 46 is supported by a bearing 41 a provided at the center of the valve seat 41.

  A valve body 47 is connected to the lower end of the rotating shaft 43 by the joint 45. The valve element 47 is pressed against the valve seat 41 by the urging force of the compression coil spring 44, and the valve element 47 is integrally formed with the rotor 42 with the rotation of the rotor 42. It is designed to rotate while sliding on the upper surface.

  The lower end of the valve element 47 has an annular shape centered on the pin 46, and a cutout 47a is provided in a part of the annular shape. The valve seat 41 is provided with first and second outlet pipes 48 and 49 located on a locus on which the lower end surface of the valve element 47 moves. It can flow out to the outlet pipe 48 or 49 through a valve hole (port) depending on the position. The outlet pipes 48 and 49 are arranged at an angle of 90 ° about the pin 46. Further, an inlet pipe 51 is provided outside the locus of movement of the lower end surface of the valve body 47, and the refrigerant flows into the valve chamber 50 from the inlet pipe 51 through the valve hole.

  A fan-shaped contact portion 47b is provided on the outer peripheral surface of the valve body 47 above the notch portion 47a, and the upper surface of the valve seat 41 contacts the contact portion 47b to rotate the valve body 47. A pin-shaped stopper 52 for regulating (corresponding to a position regulating means in the present invention) is fixed vertically (see FIG. 4).

  The stepping motor 34 has a four-phase winding configuration. The drive circuit 33 shown in FIG. 2 receives a command from the control device 28 and outputs, for example, a 30 pps forward or reverse drive pulse to the stator winding 37 by 1-2 phase excitation. ing. When a drive pulse is applied to the stator winding 37, the rotor 42, the valve body 47, and the like are integrally rotated in the forward direction (the direction of the arrow A shown in FIG. 4) or the reverse direction by an angle corresponding to the number of pulses. Rotate.

  In this case, when the number of drive pulses is 0, the cutout portion 47a of the valve body 47 is located at the valve hole of the first outlet pipe 48 when the position where the contact portion 47b abuts on the stopper 52 is the initial position. In this state, the second outlet pipe 49 is closed, and the refrigerant flowing into the valve chamber 50 from the inlet pipe 51 flows out through the first outlet pipe 48. On the other hand, when 30 drive pulses are given in the normal rotation direction to the initial position, the cutout portion 47 a of the valve body 47 is located at the valve hole of the second outlet pipe 49. In this state, the first outlet pipe 48 is closed, and the refrigerant flowing into the valve chamber 50 from the inlet pipe 51 flows out through the second outlet pipe 49. Further, when 60 drive pulses are given in the normal rotation direction to the initial position, the outlet pipes 48 and 49 are both closed by the valve body 47.

  In the refrigeration cycle 2 shown in FIG. 1, the inlet pipe 51 is connected to the refrigerant flow pipe 22 leading to the condenser 19, and the first and second outlet pipes 48, 49 are respectively connected to the capillary tubes 21a, 21b. It is connected to the.

  Next, the drive timing of the electric three-way valve 20 for reducing the noise (mute) of the electric three-way valve 20 will be described with reference to the timing chart of the operation state of the refrigerator shown in FIG. In FIG. 5, during the period from time t1 to time t2, the operation of the compressor motor 17a and the fan motors 11a and 15a is stopped (stop mode). At this time, the temperature of the refrigerating compartment 4 detected by the refrigerating compartment temperature sensor 24 is equal to or lower than the refrigerating compartment upper limit set temperature, and the temperature of the refrigerating compartment 5 detected by the freezing compartment temperature sensor 25 is equal to or lower than the freezing compartment upper limit set temperature. ing.

  In this case, since no operation sound is generated from the refrigerator, when the electric three-way valve 20 is switched, the operation sound may be heard as annoying sound or abnormal sound for the user. Therefore, the control device 28 does not perform the switching operation of the electric three-way valve 20 during the stop mode.

  By the way, the electric three-way valve 20 needs an operation called “initialization” (corresponding to the position initialization operation in the present invention). The control device 28 performs open loop control without position feedback of the valve element 47 (or the rotor 42) for the stepping motor 34. Therefore, as the switching operation is repeatedly performed, the command position and the actual position of the valve element 47 are changed. In some cases. When the power is turned on or when the power is restored from a power failure (including an instantaneous power failure), the position of the valve element 47 is unknown.

  Therefore, the control device 28 adjusts the position of the valve body 47 with respect to the stator winding 37 via the drive circuit 33 at the time of power-on, at the time of power recovery from a power failure, and once every two to three days. A drive pulse in the reverse direction for moving to the initial position is applied. In this case, a sufficient number of drive pulses are applied so that the valve body 47 can return to the initial position even if it is at the position farthest from the initial position.

  When this initialization is performed, the contact portion 47b hits the stopper 52 when the valve body 47 reaches the initial position, and a hitting sound is generated. Further, even after the valve body 47 reaches the initial position and before the drive pulse in the reverse rotation stops, the valve body 47 continues to hit the stopper 52 intermittently, so that a sound is generated. Such hit sounds may be heard as abnormal sounds by the user. Therefore, the control device 28 does not execute the initialization of the electric three-way valve 20 during the period of the stop mode in which no operation sound is generated from the refrigerator.

  Now, when the temperature of the refrigerator compartment 4 gradually rises and the temperature of the refrigerator compartment 4 exceeds the refrigerator compartment upper limit set temperature at time t2, the control device 28 switches from the stop mode to the refrigerator compartment cooling mode. Then, the control device 28 starts driving the compressor motor 17a via the inverter 29, and starts driving the refrigerator compartment fan motor 11a via the inverter 30. Further, the control device 28 starts driving the compressor cooling fan motor 18a via the drive circuit 32 together with driving the compressor motor 17a.

  In this case, until the rotation speed of the compressor motor 17a increases to some extent and a sufficient compression / condensation process of the refrigerant by the compressor 17 and the condenser 19 is established (time Ta: for example, 10 seconds to 30 seconds). The refrigerant flowing into the electric three-way valve 20 is in a gaseous state or a state in which gas and liquid are mixed. Further, the rotation speed of the refrigerator motor 11a is gradually increased by the inverter 30, and becomes stable after a lapse of time Tb (for example, 4 seconds to 6 seconds) from the start of driving. Although not shown in FIG. 5, the rotation speed of the compressor cooling fan motor 18a also gradually increases, and becomes stable after, for example, the time Tb has elapsed.

  Thus, the control device 28 executes the initialization of the electric three-way valve 20 at time t3 after a longer time of the predetermined time Ta or Tb has elapsed from time t2. The state in which the initialization has been completed is a state in which the refrigerant outflow path from the electric three-way valve 20 has been switched to the first outlet side. When the electric three-way valve 20 is initialized at such a timing, it is possible to suppress the sound generated from the electric three-way valve 20 at the following three points.

  First, since the initialization is performed after the refrigerant flows in a liquid state inside the electric three-way valve 20, the liquid refrigerant acts as a buffer against the movement of the valve element 47. As a result, the moment when the contact portion 47b of the valve element 47 hits the stopper 52 is suppressed, and the hitting sound is reduced. According to the test of the inventor of the present invention, at a distance of 10 cm from the electric three-way valve 20, the hitting sound which was 50 to 60 dB (A) in the past was reduced to about 40 to 50 dB (A).

  Secondly, the initialization of the electric three-way valve 20 is performed after the compressor motor 17a rotates and the refrigerator-room fan motor 11a and the compressor-cooling fan motor 18a have a stable rotation speed. Is masked by the operating noise of the compressor 17 and the operating noise of the refrigerator compartment fan 11 and the compressor cooling fan 18 (for example, wind noise), that is, the background noise, so that the user is less likely to be perceived as annoying sound or abnormal sound. A noise-reducing effect is obtained.

  Third, since a lubricating film made of a mixture of the refrigerant and the refrigerating machine oil is formed on the sliding surface between the lower end surface of the valve body 47 and the upper surface of the valve seat 41, the sliding generated when the valve body 47 moves. The dynamic noise is reduced, and the wear of the valve body 47 and the valve seat 41 can be reduced. Thereby, the reliability of the electric three-way valve 20 is improved.

  Thereafter, when the refrigerator compartment 4 is cooled and the temperature of the refrigerator compartment 4 becomes equal to or lower than the refrigerator compartment lower limit set temperature at the time t4, the controller 28 sets the condition that the temperature of the refrigerator compartment 5 is higher than the refrigerator compartment lower limit set temperature. Then, the mode is switched from the refrigerator compartment cooling mode to the freezer compartment cooling mode. Then, the control device 28 stops the refrigerating room fan motor 11a, and at the same time, starts driving the freezing room fan motor 15a via the inverter 31.

  In this case as well, at time t5 after the fan motor 15a has attained a stable rotation speed, the control device 28 transmits a forward drive pulse to the stepping motor 34 of the electric three-way valve 20 through the drive circuit 33 for 30 seconds. A pulse is applied to switch the refrigerant outflow path from the electric three-way valve 20 from the first outlet side to the second outlet side.

  When the electric three-way valve 20 is switched at such a switching timing, the sliding noise of the valve element is caused by the operating noise of the compressor 17 and the operating noise of the freezer compartment fan 15 (for example, wind noise) as in the above-described initialization. It is masked to get a silencing effect. In addition, a lubricating film is formed on a sliding portion between the valve element 47 and the valve seat 41, so that a noise reduction effect in which the sliding sound of the valve element 47 is reduced can be obtained, and wear of the valve element 47 and the valve seat 41 can be suppressed.

  At the subsequent time t6, even when the control device 28 switches from the freezer compartment cooling mode to the refrigerator compartment cooling mode, the control device 28 reversely rotates the stepping motor 34 of the electric three-way valve 20 at the same switching timing (time t7). 30 drive pulses in the direction are applied, and the refrigerant outflow path from the electric three-way valve 20 is switched from the second outlet side to the first outlet side.

  As described above, according to the present embodiment, the control device 28 initializes or switches the electric three-way valve 20 after the refrigerant starts flowing in a liquid state inside the electric three-way valve 20, so that the valve body 47 The liquid refrigerant acts as a cushioning material against the movement, so that the contact noise between the valve element 47 and the stopper 52 and the sliding sound between the valve element 47 and the valve seat 41 can be suppressed to a small level (silent effect).

Further, the control device 28 initializes or switches the electric three-way valve 20 after the compressor motor 17a is rotated and the fan motor 11a or 15a and the compressor cooling fan motor 18a have reached a stable rotation speed. The sliding noise is masked by the operating sound of the compressor 17 and the operating sounds of the fans 11, 15, and 18, ie, the background noise (silence effect).
As a result of such a silent effect and a silencing effect, the sound generated from the electric three-way valve 20 is less likely to be perceived as harsh or abnormal by the user. Further, it is not necessary to take soundproofing measures for the electric three-way valve 20, and the cost can be reduced.

The present invention is not limited to the embodiment described above and shown in the drawings. For example, the present invention may be configured as follows.
That is, after the refrigerant flows in a liquid state inside the electric three-way valve 20, the control device 28 controls the electric three-way valve 20 at an arbitrary timing regardless of the operation state of the fans 11, 15, and 18. It may be initialized or switched.

After the fan motors 11a and 15a or the compressor cooling fan motor 18a has reached a stable rotation speed, the control device 28 controls the electric three-way valve 20 at an arbitrary timing regardless of the state of the refrigerant in the electric three-way valve 20. May be initialized or switched.
The refrigeration cycle 2 is not limited to the one described above as long as it has an electric valve for switching the refrigerant flow path. Further, the switching valve is not limited to the above-described electric three-way valve as long as it is a motor-operated valve, and can be similarly applied to an electric three-way valve or an electric two-way valve having another configuration. Further, the motor of the electric valve is not limited to the stepping motor.
For example, an electric valve for a refrigeration cycle, such as an air conditioner or an ice maker, in which a valve portion is provided in a refrigerant flow path of a refrigeration cycle and a valve body of the valve portion is moved by a motor, the above-described refrigerator By the same means as described above, the noise can be reduced (silenced).

The figure which shows the schematic structure of the refrigerator main body and the refrigerating cycle in one Embodiment of this invention actually Diagram showing the electrical configuration of the refrigerator by combining functional blocks Longitudinal sectional view of an electric three-way valve Bottom view of electric three-way valve Timing chart for explaining the switching timing of the electric three-way valve

Explanation of reference numerals

  In the drawing, 2 is a refrigeration cycle, 4 is a refrigerator, 5 is a refrigerator, 10 is a refrigerator cooler, 11 is a refrigerator fan (cooling fan in the refrigerator), 14 is a refrigerator cooler, and 15 is freezing. Room fan (in-compartment cooling fan), 17 is a compressor, 18 is a compressor cooling fan, 19 is a condenser, 20 is an electric three-way valve (switching valve), 28 is a control device (control means), 34 is stepping A motor, 35 is a valve section, 40 is a valve body, 42 is a rotor, 47 is a valve body, and 52 is a stopper (position regulating means).

Claims (15)

A compressor,
A condenser for liquefying the refrigerant discharged from the compressor,
A switching valve for switching the flow of the refrigerant so that the refrigerant liquefied by the condenser is selectively passed through the plurality of refrigerant flow paths,
And a control means for controlling the operation of the switching valve.
The switching valve is a motor-operated valve including a motor and a valve unit configured to move a valve body in a valve body with respect to an initial position as a rotor of the motor rotates,
The valve unit includes a position regulating unit that restricts the valve body from moving beyond the initial position,
The control means is configured such that after a predetermined time has elapsed from the start of operation of the compressor in a state where the refrigerant is circulated through the refrigerant flow path, a liquid refrigerant exists in the valve body of the switching valve. The refrigerator is configured to perform a position initializing operation of moving the valve body to the initial position only when the operation is performed. A compressor,
A condenser for liquefying the refrigerant discharged from the compressor,
A switching valve for switching the flow of the refrigerant so that the refrigerant liquefied by the condenser is selectively passed through the plurality of refrigerant flow paths,
And a control means for controlling the operation of the switching valve.
The switching valve is a motor-operated valve including a motor and a valve unit configured to move a valve body in a valve body as a rotor of the motor rotates,
The control means is configured such that after a predetermined time has elapsed from the start of operation of the compressor in a state where the refrigerant is circulated through the refrigerant flow path, a liquid refrigerant exists in the valve body of the switching valve. A refrigerator which is configured to perform the switching operation of the switching valve only when the refrigerator is in operation. In the refrigerant channel, a refrigerator cooler for cooling the refrigerator compartment and a refrigerator cooler for cooling the refrigerator compartment are provided,
The plurality of refrigerant flow paths mainly include a first refrigerant flow path for supplying a refrigerant to the refrigerator compartment cooler, and a second refrigerant flow path for mainly supplying the refrigerant to the freezer compartment cooler,
The refrigerator according to claim 1, wherein the switching valve is an electric three-way valve that selectively causes the refrigerant to flow through the first refrigerant channel or the second refrigerant channel. 4. A compressor,
A condenser for liquefying the refrigerant discharged from the compressor,
A switching valve for switching the flow of the refrigerant so that the refrigerant liquefied by the condenser is selectively passed through the plurality of refrigerant flow paths,
Control means for controlling the operation of the switching valve;
A cooler provided in the refrigerant flow path,
An internal cooling fan for sending cool air generated by the cooler into the internal storage;
In a refrigerator comprising a compressor cooling fan for cooling the compressor,
The switching valve is a motor-operated valve including a motor and a valve unit configured to move a valve body in a valve body with respect to an initial position as a rotor of the motor rotates,
The valve unit includes a position regulating unit that restricts the valve body from moving beyond the initial position,
The refrigerator, wherein the control unit is configured to perform a position initialization operation of moving the valve body to the initial position only during operation of the compressor cooling fan.   The control means, during the operation of the compressor cooling fan, after a predetermined time has elapsed from the start of operation of the compressor in a state in which the refrigerant is allowed to flow through the refrigerant flow path, in the valve body of the switching valve The refrigerator according to claim 4, wherein the position initialization operation is performed when a liquid refrigerant is present.   The refrigerator according to claim 4 or 5, wherein the control means is configured to perform the position initialization operation after the operation state of the compressor cooling fan is stabilized. A compressor,
A condenser for liquefying the refrigerant discharged from the compressor,
A switching valve for switching the flow of the refrigerant so that the refrigerant liquefied by the condenser is selectively passed through the plurality of refrigerant flow paths,
Control means for controlling the operation of the switching valve;
A cooler provided in the refrigerant flow path,
An internal cooling fan for sending cool air generated by the cooler into the internal storage;
In a refrigerator comprising a compressor cooling fan for cooling the compressor,
The switching valve is a motor-operated valve including a motor and a valve unit configured to move a valve body in a valve body as a rotor of the motor rotates,
The refrigerator, wherein the control means is configured to perform the switching operation of the switching valve only during operation of the compressor cooling fan.   The control means, during the operation of the compressor cooling fan, after a predetermined time has elapsed from the start of operation of the compressor in a state in which the refrigerant is allowed to flow through the refrigerant flow path, in the valve body of the switching valve The refrigerator according to claim 7, wherein the switching operation is performed only when a liquid refrigerant is present.   9. The refrigerator according to claim 7, wherein the control unit is configured to perform the switching operation after the operating state of the compressor cooling fan is stabilized. The cooler is composed of a refrigerator cooler for cooling the refrigerator compartment and a refrigerator cooler for cooling the freezer compartment,
The cooling fan in the refrigerator includes a refrigerator fan for sending cold air generated by the refrigerator cooler to the refrigerator, and a freezer fan for sending cool air generated by the freezer cooler to the freezer. Composed,
The plurality of refrigerant flow paths mainly include a first refrigerant flow path for supplying a refrigerant to the refrigerator compartment cooler, and a second refrigerant flow path for mainly supplying the refrigerant to the freezer compartment cooler,
The refrigerator according to any one of claims 4 to 9, wherein the switching valve is an electric three-way valve that selectively causes a refrigerant to flow through the first refrigerant channel or the second refrigerant channel. .   The refrigerator according to any one of claims 1 to 10, wherein the motor of the switching valve is a stepping motor. A valve unit that is provided in a refrigerant flow path of a refrigeration cycle including a compressor, and is configured to open and close the refrigerant flow path by moving a valve body in a valve body with reference to an initial position,
A motor for moving the valve body of the valve unit with the rotation of the rotor,
Position regulating means provided on the valve portion, which restricts the valve body from moving beyond the initial position,
Provided to control the operation of the valve body via the motor, after a predetermined time has elapsed from the start of operation of the compressor in a state where the refrigerant flows through the refrigerant flow path, the An electric valve for a refrigeration cycle, comprising: control means for executing a position initialization operation of moving the valve body to the initial position only when a liquid refrigerant is present in the valve body. A valve unit that is provided in a refrigerant flow path of a refrigeration cycle including a compressor, and is configured to open and close the refrigerant flow path by moving a valve body in a valve body.
A motor for moving the valve body of the valve unit with the rotation of the rotor,
Provided to control the operation of the valve body via the motor, after a predetermined time has elapsed from the start of operation of the compressor in a state where the refrigerant flows through the refrigerant flow path, the An electric valve for a refrigeration cycle, comprising: control means for executing an operation of moving the valve only when a liquid refrigerant exists in the valve body. A valve unit provided in the refrigerant flow path of the refrigeration cycle, wherein the valve body in the valve body is configured to open and close the refrigerant flow path by being moved with reference to the initial position,
A motor for moving the valve body of the valve unit with the rotation of the rotor,
Position regulating means provided on the valve portion, which restricts the valve body from moving beyond the initial position,
Position initialization provided to control the operation of the valve body via the motor, and moving the valve body to the initial position only during operation of a blower fan that blows a compressor or a condenser of the refrigeration cycle. An electric valve for a refrigeration cycle, comprising: a control unit for executing an operation. A valve unit provided in the refrigerant flow path of the refrigeration cycle, and configured to open and close the refrigerant flow path by moving a valve element in the valve body;
A motor for moving the valve body of the valve unit with the rotation of the rotor,
Control means for controlling the operation of the valve element via the motor, and performing an operation of moving the valve element only during operation of a blower fan for blowing a compressor or a condenser of the refrigeration cycle; and An electric valve for a refrigeration cycle, comprising:

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