JP2011064373A - Ice-making device for refrigerator-freezer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new mechanism capable of producing transparent ice in an ice-making device for a refrigerator-freezer. <P>SOLUTION: The ice-making device 10 is installed in an ice-making chamber 4 of the refrigerator-freezer 1. The ice-making device 10 includes: a chill tray 20 making ice by cold air blown into the ice-making chamber 4; a thermistor 25 for measuring a temperature in the chill tray 20; a heater 31 for heating the chill tray 20 from the lower side; and a control part 50 performing the operation control of a refrigerating cycle and the current-carrying control of the heater 31 by using the measured temperature by the thermistor 25 as a criterion. The control part 50 executes: a freezing preparation step of carrying current to the heater 31 for "preheating" until the measured temperature by the thermistor 25 is lowered to zero or lower after water supply to the chill tray 20; an ice melting step of carrying a current to the heater 31 for "rapid heating" for a certain time after the measured temperature by the thermistor 25 is lowered to zero or lower; and a freezing progress step of carrying a current to the heater 31 for "normal heating" until the measured temperature by the thermistor 25 is lowered to a predetermined temperature. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ice making device for a refrigerator-freezer.

  A refrigerator-freezer generally includes an ice making device that makes ice using cold air for freezing. Examples of the ice making device disposed in the freezer can be seen in Patent Documents 1-7.

  Ice produced by an ice making device of a refrigerator is usually low in transparency. Thus, efforts have been made to increase the transparency of ice. The ice making device described in Patent Documents 1-7 includes such a device.

  In the ice making devices described in Patent Documents 1 and 2, a heater is provided above the ice tray, and the temperature of the upper portion of the ice tray is higher than that of the lower portion so that ice is generated sequentially from the lower portion inside the ice tray. ing. This makes it easier for air in the water to escape from above during the ice formation process, and transparent ice that does not contain air is produced. The ice making device described in Patent Document 3 also has a structure in which a heater is provided above the ice making tray.

  In the ice making device described in Patent Literature 4-7, the transparent ice part and the cloudy ice part are generated in a connected state, and when the ice is removed, the transparent ice part and the cloudy ice part are cut, Is left in an ice tray, so that only clear ice is removed.

JP-A-4-260768 JP-A-5-196331 JP-A-1-203869 JP 2007-232336 A JP 2007-232336 A JP 2008-151504 A JP 2008-157619 A

  An object of this invention is to provide the new mechanism which produces | generates transparent ice in the ice making apparatus of a refrigerator-freezer.

  In order to achieve the above object, the present invention provides an ice tray that is placed in an ice making chamber and performs ice making with cold air blown into the ice making chamber, a thermistor that measures the temperature in the ice tray, and the ice tray from below. In the ice making device of the refrigerator-freezer comprising a heater to be heated and a control unit for performing operation control of the refrigeration cycle and energization control of the heater using the temperature measured by the thermistor as a judgment material, the control unit supplies the ice tray After supplying water, the heater is energized to control the progress of freezing, and an ice melting step is performed at the initial energization of the heater.

  By freezing the ice tray while being heated with a heater from below, transparent ice grows not from a portion in contact with the inner surface of the ice tray, but from a portion away from the inner surface of the ice tray. When freezing is complete, air escapes from the outer periphery, leaving bubbles and irregularities on the surface, but the irregularities on the outer peripheral surface quickly melt into the liquid, quickly cooling the liquid and clear ice. Only remains after. This makes it possible to provide the user with a landscape where transparent ice floats in the liquid.

  During ice making, if existing ice is attached to the inner surface of the ice tray, it will hinder obtaining transparent ice, but since the existing ice is once melted, it will be shifted to the production of transparent ice. The part can be enlarged.

  Also, the present invention provides the ice making device for a refrigerator-freezer configured as described above, wherein the controller is configured to compare the heater with “normal heating”, “preheating”, which generates less heat than “normal heating”, and “normal heating”. Energization control is performed in three stages of “rapid heating” with a large calorific value. After supplying water to the ice tray, the heater is energized with “preheating” until the measured temperature of the thermistor drops below the freezing point. A preparation step, an ice melting step in which the heater is energized with "rapid heating" for a predetermined time after the measured temperature of the thermistor drops below freezing point, and the heater until the measured temperature of the thermistor drops to a predetermined temperature. And a freezing progress step in which energization of “normal heating” is performed.

  According to this configuration, it is possible to reliably generate transparent ice by applying a beam to the heating by the heater.

  Further, the present invention is the ice making device for a refrigerator with the above-described configuration, wherein the control unit stops energizing the heater when the compressor in the refrigeration cycle enters a stop period in the freezing preparation step. It is characterized by that.

  What is required of the heater in the freezing preparation step is to brake a sudden temperature drop. While the compressor is in operation, the above-mentioned purpose can be achieved by energizing the heater. However, during the compressor stop period, the temperature drop is naturally braked and the necessity of energizing the heater is reduced, so the energization of the heater is stopped. Thereby, it is not necessary to waste power consumption.

  Further, the present invention is the ice making device for a refrigerator with the above configuration, wherein the control unit stops energization of the heater when the measured temperature of the thermistor is a predetermined value or more in the freezing preparation step. It is said.

  If the heater is energized until the temperature of the water supplied to the ice tray is high, the ice making time will be long. According to this configuration, when the temperature of the thermistor is, for example, 1 ° C. or higher, if the power supply to the heater is stopped, the heater can be used until there is no risk of freezing from the point where water contacts the ice tray. It is possible to avoid wasting power by energizing.

  Further, the present invention provides the ice making device for the refrigerator-freezer having the above-described configuration, wherein, in the ice melting step, the controller performs “rapid heating” on the heater regardless of whether the compressor in the refrigeration cycle is operating or stopped. "Is conducted.

  According to this structure, the melting of ice can be advanced at a stretch.

  Further, the present invention provides the ice making device for a refrigerator with the above-described configuration, wherein the control unit stops energizing the heater when the compressor in the refrigeration cycle enters a stop period in the freezing progression step. Then, after restarting the compressor operation, the heater is energized for “rapid heating” for a certain period of time.

  Since the necessity of temperature control by energizing the heater is reduced when the compressor is stopped, the energization is stopped at this time to avoid wasteful power consumption. However, since the inside of the ice making cell may be frozen when the compressor operation is resumed due to the stop of energization of the heater, the heater is `` rapidly heated '' for a certain time after the compressor operation is resumed. If there is freezing on the inner surface of the ice tray, thaw it. Thereby, although energization to a heater is intermittent, generation of transparent ice can be performed continuously.

  Further, the present invention is the ice making device of the refrigerator-freezer configured as described above, wherein the control unit stops energizing the heater after the measured temperature of the thermistor has dropped to a predetermined temperature in the freezing progress step, and a certain time has elapsed. Then, it is characterized by having the ice removal device perform the ice removal operation.

  According to this configuration, the ice can be removed after the generation of transparent ice is ensured, and the transparent ice can be consumed.

  In the ice making device for a refrigerator / freezer having the above-described configuration, the control unit may gradually decrease the energization current to the heater after the measured temperature of the thermistor drops to a predetermined temperature in the freezing advance step. It is characterized in that the de-icing operation is performed by the de-icing device after the energization is stopped and a certain time has elapsed.

  The temperature of each ice making cell in the ice tray is not necessarily the same as the temperature measured by the thermistor. Even if the measured temperature of the thermistor drops to a predetermined temperature, some ice-making cells have not dropped so far, and unfrozen water may remain. Rather than stopping the energization of the heater at once when the measured temperature of the thermistor drops to the predetermined temperature, the water is not frozen by performing a process of gradually decreasing the energization current to stop the energization. It can be prevented from remaining.

  Further, the present invention is the ice making device for a refrigerator with the above-described configuration, wherein the control unit generates an energization current to the heater when the indoor temperature of the ice making chamber or the cold air temperature blown into the ice making chamber is equal to or higher than a predetermined value. It is characterized by a low level.

  According to this configuration, the ice making process can be optimized by energizing the heater by the amount of heat necessary to control the progress of freezing.

  Further, the present invention provides the ice making device for a refrigerator-freezer configured as described above, wherein the control unit rotates the compressor during the refrigeration cycle when the cold room temperature is set to be relatively high when the outside air temperature is low. And the number of rotations of the blower that sends cold air to the ice making chamber is reduced.

  If the temperature of the refrigerator compartment is set to be relatively high when the outside air temperature is low, the operation time of the compressor is usually shortened, the time for the cold air to hit the ice tray is shortened, and the ice making time is prolonged. In such a case, by reducing both the rotation speed of the compressor and the rotation speed of the blower, the operation time of the compressor can be extended and the ice making time can be shortened.

  According to the present invention, the ice tray is frozen while being heated with a heater from the bottom, and the surface is uneven due to the traces of bubbles that have escaped from the outer periphery, but the core portion that occupies the majority is transparent ice. Can be obtained. In addition, it is possible to obtain homogeneous transparent ice while preventing waste of electric power and optimizing the ice making process.

It is a front view of a refrigerator-freezer provided with an ice making device. It is a partial vertical sectional view of a refrigerator-freezer showing an ice making device. FIG. 3 is a vertical sectional view of the ice making device, taken in a direction perpendicular to FIG. 2. It is a perspective view of the ice tray in the upside down state and the thermistor combined therewith. It is a perspective view of the ice tray in the upside down state and the heater and cover combined therewith. It is a perspective view of the state which attached the cover of the heater to the ice tray in the upside down state. It is a control block diagram of a refrigerator-freezer. It is a flowchart which shows operation | movement of an ice making apparatus. It is a flowchart which shows different operation | movement of an ice making apparatus.

  A refrigerator-freezer 1 shown in FIG. 1 includes a refrigerator compartment 2 having doors 3L and 3R with double doors at the top, an ice making chamber 4 with doors 5 and a freezer compartment 6 with doors 7 at the next stage, and the next. The stage is a drawer-type freezer compartment 8 and the bottom stage is a drawer-type vegetable compartment 9. A refrigeration cycle (not shown) including a compressor and a heat exchanger generates cold air, and the cold air is distributed to each room through a duct so that a refrigeration temperature or a freezing temperature required in each room is obtained. This mechanism is well known and will not be described in detail.

  An ice making device 10 shown in FIGS. 2 and 3 is installed on the ceiling of the ice making chamber 4. Hereinafter, the structure will be described with reference to FIGS.

  FIG. 2 is a cross-sectional view of the ice making device 10 as viewed from the left side of the refrigerator-freezer 1. A duct 11 for blowing cold air into the ice making chamber 4 is formed on the wall behind the ice making chamber 4. An ice tray casing 12 extends forward from the upper end of the duct 11. The ice tray casing 12 has an open bottom surface for dropping ice produced by the ice tray. A cold air discharge port 13 is formed in the duct 11 toward the inside of the ice tray casing 12.

  Inside the ice tray casing 12, an ice tray 20 is disposed at a position to receive the cold air blown from the cold air outlet 13. The ice tray 20 is formed of a synthetic resin that does not lose its elasticity even at low temperatures. Further, when bubbles in the supplied water adhere to the inner surface of the ice tray 20, it becomes difficult to obtain transparent ice. Therefore, it is desirable to take measures that make it difficult for bubbles to adhere, such as using polypropylene blended with silicone as a molding material or coating the molded ice tray 20 with a fluororesin.

  Fine particles attracted by static electricity generated on the surface of the ice tray 20 also hinder the generation of transparent ice. Therefore, measures such as molding the ice tray 20 with a material that does not easily generate static electricity, for example, a resin compounded with silicone or an antistatic agent, or applying an antistatic agent to the ice tray 20 after molding. It is desirable to apply.

  The ice tray 20 includes a total of eight ice making cells 21 for producing ice having a trapezoidal cross section. The eight ice making cells 21 are arranged in two columns and four rows, and therefore the ice tray 20 has an elongated planar shape. Thus, the elongate ice tray 20 is arrange | positioned in the form which makes the longitudinal direction correspond with the depth direction of the refrigerator-freezer 1.

  A support shaft 22 is formed at one end in the longitudinal direction of the ice tray 20, and a socket portion 23 is formed at the other end. The support shaft 22 is rotatably supported by the ice tray casing 12. The socket portion 23 is coupled to a shaft of an ice removing device 24 (see FIG. 3) provided inside the ice tray casing 12 and is supported by the ice removing device 24. The support shaft 22 and the socket portion 23 are disposed on a common horizontal axis. The ice removing device 24 includes a motor and a speed reducer, and gives the ice tray 20 rotation within a certain angle range with the horizontal axis as the rotation axis.

  A thermistor 25 is disposed on the lower surface of the ice tray 20 at a position between the ice making cells 21 arranged in two rows. The thermistor 25 measures the temperature inside the ice making cell 21 across the wall of the ice making cell 21.

  The thermistor 25 is fixed by a thermistor cover 26. Pins 27 protrude from the four corners of the thermistor cover 26 in a direction perpendicular to the longitudinal direction of the ice tray 20. A total of four legs 28 project from the lower surface of the ice tray 20 so as to surround the thermistor 25. A horizontal through hole 29 through which the pin 27 passes is formed at the tip of the leg portion 28. The thermistor 25 is fixed by overlapping the thermistor protection sealer 30 on the thermistor 25, overlapping the thermistor cover 26 thereon, and engaging the pins 27 with the horizontal through holes 29 of the legs 28.

  In addition to the thermistor 25, a heater 31 shown in FIG. 5 is disposed on the lower surface of the ice tray 20. The heater 31 is a heating wire covered with a silicone resin, and the entire heater 31 is flexibly finished so that it can follow the twisting of the ice tray 20. Parallel ribs 32 that receive the heaters 31 are formed at the apex portions of each ice making cell 21 in the upside down state.

  The parallel ribs 32 are two ribs arranged in parallel at a predetermined interval, and the interval between the ribs is set so that the heater 31 can be received in the form of a clearance fit. The interval between the ribs is set in this way so that the heater 31 can move freely to some extent when the ice tray 20 is twisted.

  The heater 31 is routed so as to draw a symmetrical shape to the left and right of the longitudinal center line of the ice tray 20. In the embodiment, the overall shape is substantially U-shaped. A pair of feed lines 33 is connected to a location that is an open end of the U-shape.

  Since the heater 31 has a small design heat generation amount, the heater 31 has a structure in which an extremely thin heating wire is wound around the core of the glass fiber, and if the winding is twisted in a tightening direction, the heating wire is easily cut. Therefore, in addition to allowing the heater 31 to move freely to some extent as described above, the overall routing shape of the heater 31 is also set so that an excessive force is not applied to the heating wire as much as possible.

  The heater 31 is placed in the parallel ribs 32 and brought into close contact with the lower surface of the ice tray 20, and the lower surface of the ice tray 20 is covered with a cover 34. The cover 34 prevents cold air from entering the lower surface portion of the ice tray 20, uniformizes the temperature distribution between the ice making cells 21, and holds the heater 31 in the parallel ribs 32. .

  The cover 34 has a rectangular tray shape, and a ring 35 through which the support shaft 22 passes is formed at one end. The cover 34 is attached to the ice tray 20 with two screws 36 and one spring 37 after the ring 35 is fitted to the support shaft 22. The attachment of the cover 34 is not so hard as to restrain the movement of the ice tray 20 and is flexible so as not to disturb the twisting of the ice tray 20 at the time of deicing. As with the ice tray 20, the cover 34 itself is desirably molded from a synthetic resin that does not lose its elasticity even at low temperatures.

  Two through holes 38 are formed in the cover 34 near both ends of the longitudinal center line. Further, two through holes 39 are formed symmetrically with respect to the center line in the longitudinal direction at a position closer to the center of the cover than the through hole 38. The through hole 38 is circular and passes through a boss 40 having a circular cross section formed on the lower surface of the ice tray 20. The through hole 39 is rectangular, and allows the spring mounting rib 41 formed on the lower surface of the ice tray 20 to pass therethrough.

  When the screw 36 is screwed and fixed to the boss 40 exposed from the through hole 38, the cover 34 is held so as to be movable along the axis of the boss 40 in the form of using the screw 36 as a stopper for retaining. That is, the screw 36 prevents the cover 34 from being separated from the ice tray 20 without tightening the cover 34.

  When the cover 34 is secured with screws 36, the spring mounting rib 41 protrudes from the through hole 39 of the cover 34 as shown in FIG. The attachment hooks 43 at both ends of the spring 37 are engaged with the horizontal through hole 42 formed at the tip of the spring attachment rib 41. The spring 37 is formed by bending a spring steel wire into a shape in which there is a mounting hook 43 at the center in the longitudinal direction and hairpin portions 44 are present at both ends in the longitudinal direction.

  The hairpin portion 44 extends obliquely downward in FIG. 6, in other words, in the direction of the ice tray 20. For this reason, when the attachment hook 43 is engaged with the horizontal through hole 42 of the spring attachment rib 41, the hairpin portion 44 presses the cover 34. As shown in FIG. 3, the cover 34 is pressed against the heater 31 and holds the heater 31 with a constant load so as not to come out of the parallel rib 32. As a result, the heater 31 comes into close contact with the ice making cell 21 and heat can be efficiently transferred to the ice making cell 21.

  A windshield 45 extending downward is integrally formed at both longitudinal edges of the ice tray 20. The windshield plate 45 prevents cold air blown from above on the ice tray 20 from flowing downward. For this reason, it is prevented that the cold air enters the lower surface of the ice tray 20 and the effect of heating by the heater 31 is impaired, and the cold air is concentrated on the upper surface of the ice tray 20.

  A notch 46 is formed in the windshield 45 at a location that coincides with the boundary between the ice making cells 21. In the case of the embodiment, there are two notches 46 in one windshield 45. If the notch 46 is not provided, when the ice tray 20 is twisted, the stress of the windshield 45 is concentrated at one location, and the resin material at that location is whitened at an early stage and proceeds to the generation of cracks. . By forming the notches 46, the stress can be dispersed and the occurrence of whitening and cracks can be prevented.

  As shown in FIG. 3, a gap 47 is provided between the windshield plate 45 and the cover 34 so as not to cause mutual contact even if the ice tray 20 is twisted for ice removal.

  At the end of the ice tray 20 on the support shaft 22 side, a protrusion 48 is formed on one side surface. The protrusion 48 is for twisting the ice tray 20 when the ice is removed.

  It is the control unit 50 shown in FIG. 7 that performs overall control of the refrigerator-freezer 1 including operation control of the refrigeration cycle and energization control to the heater 31. The control unit 50 includes a deicing device 24 and a heater 31, a compressor 51 that forms part of the refrigeration cycle, a blower 52 that sends cold air to each part in the refrigerator, a water supply device 53 that supplies water to the ice making device 10, a temperature sensor 54, And the ice quantity sensor 55 etc. which are arrange | positioned at the ice making chamber 4 are connected. The temperature sensor 54 is a concept including a temperature measuring element such as a thermistor disposed in each part, and the thermistor 25 is also included therein.

  The controller 50 controls energization of the heater 31 in the following three stages. That is, “normal heating”, “preheating” with a smaller calorific value than “normal heating”, and “rapid heating” with a larger calorific value than “normal heating”. For example, the power consumption of “normal heating” can be set to 5 to 6 W, the power consumption of “preheating” can be set to 2 W, and the power consumption of “rapid heating” can be set to 7 to 8 W to make a difference in the heat generation amount.

  Next, the operation of the ice making device 10 will be described with reference to the flowchart of FIG. It is assumed that the flow starts when the ice removing operation is finished and the ice tray 20 returns to the upward state.

  In step # 101, the control unit 50 operates the water supply device 54 to supply water to the ice tray 20.

  Since the temperature of the ice making chamber 4 is close to the freezing temperature (set to minus 18 ° C.), the temperature of the ice tray 20 increases when water is supplied. The thermistor 25 detects this temperature rise in step # 102.

  Since the water is cooled as soon as it is supplied, the temperature measured by the thermistor 25 once rises and then begins to fall. From here, step # 103 is entered.

  Step # 103 is a freezing preparation step. The control unit 50 energizes the heater 31 with “preheating” to lower the water temperature at a predetermined rate.

  In the subsequent steps, heating by the heater 31 is performed. By freezing the ice tray 20 while being heated by the heater 31 from below, transparent ice can be grown not from the portion in contact with the inner surface of the ice tray 20 but from the portion away from the inner surface of the ice tray 20. Easy to grow high ice.

  When the compressor 51 enters the stop period in the middle of step # 103, the brake is naturally applied to the temperature drop. The controller 50 stops energizing the heater 31 and avoids unnecessary power consumption.

  The control unit 50 also stops energization of the heater 31 when the measured temperature of the thermistor 25 is equal to or higher than a predetermined value, for example, 1 ° C. or higher. Thus, it is possible to avoid wasting power by energizing the heater 31 until there is no risk of freezing from the point where water contacts the ice tray 20.

  In Step # 104, the control unit 50 checks whether or not the temperature measured by the thermistor 25 has dropped below freezing point. When the temperature falls below the freezing point, the process proceeds to step # 105.

  Step # 105 is an ice melting step. The controller 50 energizes the heater 31 for “rapid heating” for a predetermined time to heat the ice tray 20. Even if the measurement error of the thermistor 25 delays the transition from step # 104 to step # 105 and ice is attached to the inner surface of the ice making cell 21, the ice melts at this stage. . Therefore, it is possible to proceed to step # 106 without generating residual ice that hinders obtaining homogeneous transparent ice.

  In step # 105, the controller 50 energizes the heater 31 for “rapid heating” regardless of whether the compressor 51 is operating or stopped. Thereby, melting of ice can be advanced at a stretch.

  Step # 106 is a freezing progress step. The controller 50 energizes the heater 31 for “normal heating” until the temperature measured by the thermistor 25 drops to a predetermined temperature.

  When the compressor 51 enters a stop period in the middle of step # 106, the controller 50 stops energization of the heater 31 and avoids wasted power consumption. However, there is a possibility that freezing has occurred on the inner surface of the ice tray 20 when the operation of the compressor 51 is resumed by stopping energization of the heater 31. Therefore, after restarting the operation of the compressor 51, the heater 31 is energized for "rapid heating" for a certain period of time, and if freezing occurs on the inner surface of the ice tray 20, it is melted. Thereby, although energization to heater 31 is intermittent, generation of transparent ice can be performed continuously.

  In step # 107, the controller 50 checks whether the temperature measured by the thermistor 25 has dropped to a predetermined temperature. When the temperature falls to a predetermined temperature, for example, minus 9 ° C., it is determined that ice making is completed, and the process proceeds to step # 108.

  The controller 50 stops energization of the heater 31 at step # 108. When the predetermined time has elapsed, it is determined that the generation of transparent ice has been ensured, and the process proceeds to step # 109.

  In step # 109, the control unit 50 causes the ice removing device 24 to perform the reversing operation of the ice tray 20. When the ice making device 24 rotates the ice tray 20 around the support shaft 22, the protrusion 48 hits a stopper (not shown) formed on the ice tray casing 12 just before the upside down is completed. Since the ice removing device 24 continues to rotate the ice tray 20 by a predetermined angle thereafter, the ice tray 20 is twisted and deformed. As described above, a gap 47 is provided between the windshield plate 45 and the cover 34 so as not to cause mutual contact even when the ice tray 20 is twisted, so that the edge of the cover 34 and the windshield 45 are rubbed together. No squeaks or wears out.

  When the ice tray 20 is twisted, the ice in the ice making cell 21 is pushed out and falls into an ice container (not shown) placed in the ice making chamber 4. After the deicing, the deicing device 24 rotates the ice making tray 20 in the reverse direction to return the ice making tray 20 to its original orientation. Thus, one cycle of ice making work is completed. If the ice amount sensor 55 tells that the ice amount in the ice container is not yet sufficient, the ice making operation of the next cycle is started. If the ice amount sensor 55 informs that there is sufficient ice in the ice container, the ice making device 10 enters a rest period.

  The ice making device 10 can be operated as shown in the flowchart of FIG. In the flowchart of FIG. 9, steps other than step # 108 ′ are the same as those in the flowchart of FIG. In step # 108 ', after the measured temperature of the thermistor 25 drops to a predetermined temperature, the controller 50 does not immediately stop energizing the heater 31, but gradually reduces the energizing current to the heater 31 to stop energizing. To reach.

  The temperature of each ice making cell 21 does not necessarily coincide with the measured temperature of the thermistor 25. Even if the measured temperature of the thermistor 25 falls to a predetermined temperature, the temperature of some ice making cells 21 has not dropped so far, and unfrozen water may remain. Rather than stopping the energization of the heater 31 at once when the measured temperature of the thermistor 25 has dropped to a predetermined temperature, water is not discharged by performing a process of gradually decreasing the energization current to stop the energization. It can be prevented from remaining by freezing.

  The control unit 50 also operates as follows.

  When the indoor temperature of the ice making chamber 4 or the cold air temperature blown into the ice making chamber 4 is equal to or higher than a predetermined value, the control unit 50 sets the energization current to the heater 31 to a low level. As an example, the default set temperature is set to minus 18 ° C., and if the temperature is higher than minus 18 ° C., the energization current to the heater 31 is set to a low level. If the temperature is minus 18 ° C. or lower, the energization current to the heater 31 is set to the normal level.

  Thus, the ice making process can be optimized by energizing the heater 31 by the amount of heat necessary to control the progress of freezing.

  The controller 50 reduces the rotational speed of the compressor 51 and the rotational speed of the blower 52 when the temperature of the refrigerator compartment is set to be relatively high when the outside air temperature is low.

  If the temperature of the refrigerator compartment is set to be relatively high when the outside air temperature is low, the operation time of the compressor 51 is usually shortened, the time during which the cold air hits the ice tray 20 is shortened, and the ice making time is prolonged. By reducing both the rotation speed of the compressor 51 and the rotation speed of the blower 52, the operation time of the compressor 51 can be extended and the ice making time can be shortened.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  The present invention is widely applicable to ice making apparatuses for refrigerators and refrigerators.

DESCRIPTION OF SYMBOLS 1 Refrigeration refrigerator 4 Ice making room 10 Ice making apparatus 11 Duct 13 Cold air discharge port 20 Ice tray 21 Ice making cell 24 Deicing device 25 Thermistor 31 Heater 34 Cover 45 Windshield 50 Control part 51 Compressor 52 Blower 53 Water supply device

In order to achieve the above object, the present invention provides an ice tray that is placed in an ice making chamber and performs ice making with cold air blown into the ice making chamber, a thermistor that measures the temperature in the ice tray, and the ice tray from below. In the ice making device of the refrigerator-freezer comprising a heater to be heated and a control unit for performing operation control of the refrigeration cycle and energization control of the heater using the temperature measured by the thermistor as a judgment material, the control unit supplies the ice tray After supplying water, the heater is energized to control the progress of freezing, and the control unit performs heater control for energizing control to a predetermined plurality of different heat generation amounts, and in the initial stage of energizing the heater, And the ice melting step in which the heating value of the heater is a high heating value is performed.

During ice making, if existing ice adheres to the inner surface of the ice tray, it may interfere with obtaining transparent ice, but in the initial stage of energizing the heater, the amount of heat generated by the heater within the heater control is high. Since the melting step is performed and the existing ice is once melted and then transferred to generation of transparent ice, the transparent ice portion can be enlarged.

According to the present invention, the ice tray is frozen while being heated with a heater from the bottom, and the surface is uneven due to the traces of bubbles that have escaped from the outer periphery, but the core portion that occupies the majority is transparent ice. Can be obtained. And at the initial stage of energizing the heater, we decided to carry out the ice melting step where the heating value of the heater is high in the heater control, and once the existing ice was melted, we moved to the generation of transparent ice. The transparent ice part can be enlarged. In addition, it is possible to obtain homogeneous transparent ice while preventing waste of power and optimizing the ice making process.

In order to achieve the above object, the present invention provides an ice tray that is placed in an ice making chamber and performs ice making with cold air blown into the ice making chamber, a thermistor that measures the temperature in the ice tray, and the ice tray from below. In the ice making device of the refrigerator-freezer comprising a heater to be heated and a control unit for performing operation control of the refrigeration cycle and energization control of the heater using the temperature measured by the thermistor as a judgment material, the control unit supplies the ice tray After supplying water, the heater is energized to control the progress of freezing, and the control unit energizes the heater with “normal heating” and “preheating” with a smaller calorific value than “normal heating”. Control is made in three stages of “rapid heating”, which generates a larger amount of heat than “normal heating”, and the ice melting step is performed by “rapid heating” in the initial stage of energizing the heater.

At ice, the existing ice on the inner surface of the ice tray is attached, becomes a hindrance to give a clear ice, control unit and the "normal heating" the power supply to the heater, the calorific value compared to the "normal heating" It is controlled in three stages: small “preheating” and “rapid heating”, which generates a large amount of heat compared to “normal heating” . In the initial stage of energizing the heater, the ice melting step is performed by “rapid heating” . Since the existing ice is once melted and then transferred to the production of transparent ice, the transparent ice portion can be enlarged.

According to the present invention, the ice tray is frozen while being heated with a heater from the bottom, and the surface is uneven due to the traces of bubbles that have escaped from the outer periphery, but the core portion that occupies the majority is transparent ice. Can be obtained. In the initial stage of energizing the heater, the ice melting step was performed by “rapid heating”, and the existing ice was once melted and then moved to the generation of transparent ice. it can. In addition, it is possible to obtain homogeneous transparent ice while preventing waste of electric power and optimizing the ice making process.

Claims (10)

An ice making tray that is placed in an ice making chamber and performs ice making by cold air blown into the ice making chamber, a thermistor that measures the temperature in the ice making tray, a heater that heats the ice making tray from below, and a temperature measured by the thermistor In an ice making device for a refrigerator with a control unit that performs operation control of the refrigeration cycle and energization control of the heater as a determination material,
The controller is configured to control the progress of freezing by supplying power to the heater after supplying water to the ice tray, and performing an ice melting step at the initial stage of supplying power to the heater. apparatus. The control unit controls the energization of the heater in three stages: “normal heating”, “preheating” that generates less heat than “normal heating”, and “rapid heating” that generates more heat than “normal heating”. The ice making apparatus for a refrigerator-freezer according to claim 1, wherein after the water is supplied to the ice tray, the following steps are performed:
Freezing preparation step of energizing the heater with "preheating" until the measured temperature of the thermistor drops below freezing point;
An ice melting step in which the heater is energized for "rapid heating" for a certain period of time after the measured temperature of the thermistor drops below freezing;
A freezing progress step of energizing the heater with “normal heating” until the measured temperature of the thermistor drops to a predetermined temperature.   3. The ice making of a refrigerator-freezer according to claim 2, wherein the controller stops energization of the heater when the compressor in the refrigeration cycle enters a stop period in the freezing preparation step. apparatus.   The ice making device for a refrigerator / freezer according to claim 2, wherein, in the freezing preparation step, when the measured temperature of the thermistor is equal to or higher than a predetermined value, the controller stops energizing the heater.   The said control part performs electricity supply of "rapid heating" to the said heater irrespective of whether the compressor in the said refrigerating cycle is operating or stopping in the said ice melting step. The ice-making apparatus of the refrigerator-freezer of any one of these.   In the freezing progress step, when the compressor in the refrigeration cycle enters a stop period, the control unit stops energizing the heater, and after the compressor operation is resumed, The ice making device for a refrigerator-freezer according to any one of claims 2 to 5, wherein energization of "heating" is performed.   The control unit stops energization of the heater after the measured temperature of the thermistor drops to a predetermined temperature in the freezing progress step, and causes the deicing device to perform the deicing operation after a predetermined time has elapsed. The ice making device for a refrigerator-freezer according to any one of claims 2 to 6.   The controller, after the temperature measured by the thermistor drops to a predetermined temperature in the freezing progress step, gradually reduces the energization current to the heater to stop energization. The ice making device for a refrigerator-freezer according to any one of claims 2 to 6, wherein an ice removing operation is performed.   9. The control unit according to claim 1, wherein when the indoor temperature of the ice making chamber or the cold air temperature blown into the ice making chamber is equal to or higher than a predetermined value, the control unit sets the energization current to the heater to a low level. The ice making device of the refrigerator-freezer of any one of Claims.   When the temperature of the refrigerator compartment is set to be relatively high when the outside air temperature is low, the control unit sets the number of rotations of the compressor in the refrigeration cycle and the number of rotations of the blower that sends cold air to the ice making chamber. The ice making device for a refrigerator-freezer according to any one of claims 1 to 9, wherein the ice making device is lowered.

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