JPH067034B2 - refrigerator - Google Patents

Description

The present invention relates to a refrigerator in which cold air cooled by a cooler is circulated by a blower to cool the inside of a room to an ice temperature storage temperature.

(B) Conventional technology In this type of conventional refrigerator, a freezer room that is cooled to a freezing temperature such as -20 ° C and a refrigerating room that is maintained at a temperature equal to or higher than the freezing point such as + 3 ° C are configured to store meat and fish. Foods that decay quickly are stored in the freezer compartment, and foods that can be stored for a short period of time and foods that are not easily corroded are stored in the refrigerator compartment.

(C) Problems to be solved by the invention With such a structure, long-term storage of fast-rotating food cannot be expected in the refrigerating room, and long-term storage can be achieved if it is stored in the freezing room and frozen. However, if the time until freezing ends is long, the flavor is impaired during that time, and the flavor is impaired even by thawing during cooking.

Therefore, in recent years, ice-temperature storage has been proposed in which foods are stored below freezing and without being frozen. However, since this ice temperature storage temperature zone is relatively narrow, the conventional so-called ON-OFF control of the cooling action between the upper limit temperature and the lower limit temperature causes large temperature fluctuations and further depends on load conditions. There are inconveniences such that the temperature may easily rise above the freezing point or the freezing temperature may be reached.

On the other hand, Japanese Patent Application Laid-Open No. 48-21249 discloses a refrigerator control device that continuously (ie, linearly) changes the rotation speed of a fan for circulating cold air according to the temperature inside the refrigerator. If the temperature fluctuates, the fan speed will change even near the set temperature, so the air flow rate will not be stable, and it will be difficult to stabilize the internal temperature at the set temperature, and the temperature of the ice greenhouse will have a relatively narrow control temperature range. It was not suitable for control.

On the other hand, Japanese Utility Model Application Laid-Open No. 57-148689 has a fan for cooling a refrigerating room and a fan for cooling a freezing room, and the rotation speeds of both fans are digital (that is, stepwise) according to the temperatures of the refrigerator and the freezing / freezing room, respectively. ) Is disclosed, the fan motor control device in a freezer-refrigerator for maintaining the refrigerating room and the freezing room at a desired temperature is disclosed, but a compartment (that is, an ice greenhouse) that is maintained at the ice temperature temperature by indirect cooling is disclosed. Since there is no return path for the cold air introduced into the refrigerator and the refrigerator introduces part of the cold air from the freezer, the temperature in the refrigerator is likely to depend on the temperature in the freezer, and accurate temperature control cannot be performed. There was a problem that it was not suitable for application to refrigerators that require extremely fine temperature control performance, such as ice greenhouses.

Therefore, the present invention provides a refrigerator in which it is easy to maintain the compartment at an ice temperature by gradually changing the rotation speed of an auxiliary blower provided exclusively for the compartment in a refrigerator that indirectly cools the compartment according to the temperature of the compartment. The purpose is to provide.

(D) Means for solving the problem The present invention is formed with a temperature control device for controlling the compressor and the main blower based on the temperature of the freezer compartment detected by the freezer compartment sensor, and in a substantially hermetically sealed box body. A compartment having a wall surface with good heat conductivity, a cold air passage formed outside the wall surface in a heat exchange relationship to indirectly cool the compartment, an auxiliary blower for controlling the amount of cold air to the cold air passage, and In a refrigerator provided with a compartment sensor for detecting the temperature of a compartment, a temperature setting means for setting a set temperature of the compartment and a dead zone for the set temperature, and a predetermined compartment temperature detected by the compartment sensor. And a control means for controlling the rotation speed of the auxiliary blower for each predetermined time so as to increase the rotation speed during the ascent and decrease the rotation speed during the descent based on the ascending / descending state every time, and the control means, The temperature in the compartment When in the sensitive zone is obtained as the rotational speed of the rotational speed of the auxiliary blowers regardless lifting state of the temperature of the compartments were determined before a predetermined time.

(E) Action According to the present invention, since the temperature variation in the room is small and stable temperature control is possible, the room can be favorably maintained in the ice temperature storage temperature zone.

(F) Example An example will be described with reference to the drawings. FIG. 4 shows a cross-sectional view of the refrigerator (1), and FIG. 5 shows an enlarged view of the essential parts thereof.
The refrigerator (1) incorporates a synthetic resin inner box (3) inside a steel plate outer box (2) with a space, and foams urethane insulation (4) between both boxes (2) and (3). Filled to form an insulating box. refrigerator
The interior of (1) is divided into upper and lower parts by a partition wall (5) filled with a heat insulating material, and the freezing temperature (for example, -20
A freezing room (F) cooled to ℃) and a refrigerating room (R) maintained below the freezing temperature (eg + 3 ° C) above the freezing point are formed. A partition member (8) is installed across the left and right of the opening edge of the refrigerating compartment (R), which is a part of the refrigerator (1), and this partition member (8) and this partition member are substantially the same. A heat insulating partition plate (9) is attached to the groove (3a) formed in the inner box (3) at a height, and the cold storage room (R) is partitioned vertically by this partition plate (9). It In the space above the partition plate (9), a cold air passage (10) is formed with a space between the lower surface of the partition wall (5), the upper surface of the partition plate (9), both side surfaces of the inner box (3) and the rear surface, and A box-shaped case (11) made of a heat conducting member such as the above and having an opening at the front is incorporated.
The opening edge of the case (11) is an inner box (3), a partition wall (5) and a partition plate.
It is abutting against (9), which makes this case (11)
A compartment (H) that communicates only with the outside is formed inside, and the front end of the cold air passageway (10) is closed.

Above the partition wall (5), a bottom plate (13) of the freezer compartment (F) having a heat insulating material on the lower surface is provided at a distance and a cooling chamber is provided between the bottom plate (13) and the partition wall (5). (14) is formed. This cooling room (14)
A cooler (15) included in the refrigeration cycle is housed and installed therein, and a main blower (16) is provided behind the cooler (15). The motor (16M) that drives the main blower (16) is the cooling chamber.
It is located in the rear of (14) and is installed inside the outer box (2) backside and stored in the storage box (17) embedded in the heat insulating material (4),
The rotary shaft penetrates the storage box (17), the heat insulating material (4) and the inner box (3) to face the inside of the cooling chamber (14), and a blower fan (16F) is attached to the tip thereof. The main blower (16) rotates and sucks cool air in the direction of the rotation axis and blows it out in the radial direction.
The rear side (13a) of the bottom plate (13) of the freezing compartment (F) rises upward with a space from the rear surface of the inner box (3), and a duct (which connects the rear part of the cooling chamber (14) and the freezing compartment (F) ( 18) is formed, and the cold air accelerated by the main blower (16) is discharged into the freezer compartment (F) through the discharge port (18a) at the tip of the duct (18). (19) is a duct member that is attached to the back of the inner box (3) and forms a duct (20) that connects the rear part of the cooling chamber (14) and the refrigerating chamber (R), and is accelerated by the main blower (16). The cool air passes through the duct (20) and is discharged into the refrigerating compartment (R) through a discharge port (20a) formed in the upper rear portion of the refrigerating compartment (R). Cold air passage (10) Inside the inner box (3) behind the cold air passage in the upper rear
A discharge port (20b) is formed that connects the middle part of the duct (20) with the duct (20).

The amount of cold air discharged from the discharge port (20a) is adjusted by the electromagnetic damper (35). The electromagnetic damper (35) is fixed to the plunger (not shown) or electromagnetic coil (35A) housed in the case (36) and the tip of the arm (37) attached to the plunger to open and close the discharge port (20a) (a baffle plate ( 38) and. (39)
Is an auxiliary blower provided behind the discharge port (20b). The motor (39M) that drives the auxiliary blower (39) is located behind the discharge port (20b) and is installed inside the back of the outer box (2) and inside the heat insulating material (4) inside the storage box (40). The rotating shaft is stored in the storage box (4
0), through the heat insulating material (4) and the duct member (19), the duct (2
Blower fan (39F) is attached to the end of the fan. The auxiliary blower (39) rotates to blow a part of the cool air flowing down the duct (20) forward and circulate it through the discharge port (20b) into the cool air passage (10). In this way each room
(F) (R) and cold air are discharged into the cold air passage (10), and the freezer compartment (F)
The cold air that circulates through the cold air passage (10) and the cold air passage (10) are cooled directly by cooling the freezing chamber (F), and the compartment (H) is cooled by the indirect cooling from the case (11), and then cooled in front of the cooling chamber (14). The cold air suction ports (22) and (23) communicating with each other return to the cooling chamber (14). refrigerator
In the heat insulation material (4) on the side wall of (1), there is formed a return duct (24) connecting the refrigerating compartment (R) and the front part of the cooling compartment (14), and passing through this, inside the refrigerating compartment (R). The cold air of the is returned to the cooling chamber (14) from the suction port (25). (26) is a compressor included in the refrigeration cycle, (27)
(28) and (29) are doors that open and close the front openings of the chambers (F) (H) (R).

FIG. 3 is a block diagram showing the control circuit (41) of the present application. (42)
Is a microcomputer, A / D converter (43) (44)
It has the functions of (45) and (46) and the micro CPU (47). (Four
Reference numeral 9) is a sensor for detecting the temperature in the freezer compartment (F), the output of which is A / D converted by the A / D converter (43) and input to the micro CPU (47). Reference numeral (50) is a sensor for detecting the temperature in the compartment (H) or the cold air passage (10), which is also input to the micro CPU (47) via the A / D converter (44). Reference numeral (51) is a sensor for detecting the temperature in the refrigerator compartment (R), which is also input to the micro CPU (47) through the A / D converter (45). Reference numeral (52) is a means for setting the temperature of each room (F) (H) (R), and is input to the micro CPU (47) via the A / D converter (46). The two outputs of the micro CPU (47) are D / A respectively.
Analog conversion is performed by the converters (54) and (55), and then the motor (26) is passed through, for example, the inverter circuit (56) and the chopper circuit (57).
M) (16M) rotation speed is controlled respectively. (26M) is a compressor (2
6) It is a driving motor. The other output of the micro CPU (47) is similarly input to the driver (59) via the D / A converter (58) to control the energization of the electromagnetic coil (35M). Micro C
The PU (47) changes the output so that the temperature of the freezer compartment (F) becomes the temperature (for example, -20 ° C) set by the means (52),
Adjust the rotation speed of the motor (26M) (16M) to increase or decrease the cooling capacity. Also, the output is changed so that the temperature of the refrigerating room (R) becomes the temperature set by the means (52) (for example, + 3 ° C).
(59) drives the electromagnetic damper (35) to open / close the discharge port (20a).

The other output of the micro CPU (47) is the D / A converter (6
It is converted to analog after passing 0) and the chopper circuit (61) controls the rotation speed of the motor (39M). FIG. 1 shows a functional block diagram for controlling the temperature of the compartment (H) in the control circuit (41). (63) is a sensor that detects the temperature (T _P ) of the compartment (H)
The temperature detection means as a function of (50), (64) a temperature setting means of the compartment (H) as one of the functions of the means (52), and (65) a temperature (T _P ) dead zone setting means, (66) and (67) means setting the upper limit temperature and setting lower limit temperature, and (68) sets the output of the temperature detecting means (63) to the switch (69). Means for storing the temperature information inputted via (70) compares the temperature outputs of means (63) and (68) and outputs a temperature difference when a predetermined temperature difference, for example 0.5 ° C, occurs. Similarly, the judging means (72) compares the temperature outputs of the means (63) and (68) and changes the output depending on whether the temperature (T _P ) in the compartment (H) has risen or dropped. , (73)
Is a control means for controlling the means (74) for adjusting the rotation speed of the motor (39M) by inputting the outputs of the respective means (63) (70) (72) (65) (66) (67).

The control means (73) generates an output to change the rotation speed of the motor (39M) when the output of the means (70) is generated.If the temperature change increases based on the output of the means (72), the motor ( Increase the rotation speed of 39M) by one step, and decrease it by one step. Furthermore, the control means (73) without changing the rotational speed of the motor (39M) is a dead zone comprises means setting temperature (T _D) of the room temperature set by (65) (T _P), set by means (66) The maximum speed is the motor (39M) rotation speed, and the lower limit temperature set by the means (67) is the motor (3M).
The minimum speed is 9M). Further, the control means (73) opens the switch (69) upon completion of such processing, and stores the temperature (T _P ) at that time in the means (68). Therefore means (70)
(72) compares the previous temperature (T _P0 ) written in the means (68) with the current temperature (T _P1 ) from the means (63). Furthermore, the control means (73) temporarily turns on the motor (3
The maximum speed is 9M).

Next, FIG. 2 shows the compartment (H) of the microcomputer (42).
3 is a flowchart showing software for temperature control.
Start when the refrigerator (1) is turned on, and then step (76)
After resetting all with, use the motor (39
The number of rotations of M) is increased by one step from the starting state, and the process proceeds to step (78). In step (78), it is judged whether or not the rotation speed of the motor (39M) is the maximum capacity, and if not, the flow returns to step (77) to increase the rotation speed. Raised to maximum capacity the number of revolutions of the motor (39M) by repeating the above, the flow advances to step (79) When the maximum capacity, the indoor temperature (T _P) is an upper limit temperature, for example, -0.5
Judge whether or not the temperature has reached ℃, and if not, maintain that state. When the temperature (T _P ) reaches −0.5 ° C. in step (79), the process proceeds to step (80), and the temperature (T _P ) at that time, ie −0.5 ° C., is written in the temperature information storage means (68) and the step (81) is entered. Proceed to.

In step (81), the difference between the room temperature (T _P0 ) written in the temperature information storage means (68) and the current room temperature (T _P1 ) detected by the temperature detection means (63) has become 0.5 ° C. It is judged whether or not, and the state is maintained until the difference becomes 0.5 ° C. When the absolute value of the difference becomes 0.5 ° C in step (81), step (82)
Check if the temperature (T _P1 ) is −0.5 ° C. If not, proceed to step (83), where the temperature (T _P1 ) is the lower limit temperature, for example −3.5 ° C.
If not, the process proceeds to step (84). In step (84), it is judged whether the temperature (T _P1 ) is within the dead zone of the room temperature. Here, the set temperature (T _D ) is set to −2 ° C., the dead zone is lower than the upper and lower sides, for example, −1.5 ° C.
The temperature range is higher than -2.5 ° C. Therefore step
At (84), the temperature (T _P1 ) is not in the dead zone, so proceed to step (85) to judge whether the temperature (T _P1 ) is higher or lower than (T _P0 ). If so, proceed to step (86) to determine if the motor (39M) has the minimum capacity.
Decrease the rotation speed of (39M) by one step, return to step (80), and write the temperature at that time, ie, -1 ° C. After that, when it is cooled and the temperature (T _P1 ) reaches −1.5 ° C., step (81),
After going through (82), (83), and (84), the process proceeds from (85) to steps (86) and (87), further lowers the rotation speed by one step, returns to step (80), and writes -1.5 ° C. When the cooling further proceeds and reaches the set temperature (T _D ) of −2 ° C., the process proceeds from step (84) to step (88) this time via steps (81), (82) and (83). In step (88), the number of rotations of the motor (39M) is not changed and the process returns to step (80). That is, the rotation speed of the motor (39M) does not change in the dead zone.

If the cooling capacity in this state is too much for the load and the temperature (T _P1 ) drops to -2.5 ° C, the same as from step (81).
(87) is executed to decrease the rotation speed by one step, and if it is further decreased by -3 ° C, the rotation speed is similarly decreased. After that, if the temperature (T _P1 ) reaches the minimum temperature of −3.5 ° C, step (8
From 3) this time, proceed to step (89) to unconditionally set the rotation speed of the motor (39M) to the minimum capacity. Set the room temperature (T _P ) so that it will rise even under the lightest load condition with the minimum capacity. With this setting, the temperature (T _P1 ) rises to -3 ° C.
If so, the routine proceeds from step (85) to step (90), and it is judged whether or not the rotation speed is the maximum capacity. If not, the routine proceeds to step (91) to increase the rotation speed by one step. Then temperature (T _P1 )
When the temperature rises to -2.5 ° C, the rotation speed is further increased by one step. If it is in the dead zone as it is, the state is maintained without changing the rotation speed.

By repeating the above, the temperature (T _P ) of the compartment (H) converges within the dead zone, but the motor (39M) is changed every time the temperature changes by 0.5 ° C.
Since the number of rotations of is corrected, the width of so-called overshoot and undershoot is small, and the convergence to the set temperature (T _D ) becomes faster. The set temperature of −2 ° C. at this time is an ice temperature storage temperature, and the compartment (H) is an ice temperature storage space. Here, the ice temperature storage temperature is a temperature zone (for example, a range of 0 ° C. to −4 ° C.) that is below freezing but does not freeze the article,
Storing food at this temperature does not impair the flavor,
It does not need to be thawed and can be stored for a long time (about one week in the experiment). Also, for example, when the temperature (T _P ) is stable in the dead zone, the thermal load in the compartment (H) increases rapidly, and when a rapid temperature rise occurs, the temperature (T _P1 ) is the upper limit temperature. When the temperature reaches -0.5 ° C, the process proceeds from step (82) to step (92) to maximize the rotation speed of the motor (39M), so that the temperature rise can be minimized. Further, in the embodiment, the upper limit temperature is -0.5 from power-on.
The motor (39M) is unconditionally operated with the maximum capacity until the temperature reaches ℃, so the cooling speed from power-on becomes faster.

From the above, the temperature fluctuations in the compartment (H) can be minimized, so that the temperature of the compartment (H) can be satisfactorily maintained in the ice temperature storage temperature zone having a relatively narrow range as described above.

Here, the variation width of the number of revolutions per step of the motor (39M) may be appropriately set depending on the area of each ventilation passage, the capacity of the auxiliary blower (39) and the like so as not to deviate from the gist of the present application.

(G) Effect of the Invention According to the present invention, when the temperature of the compartment is in the dead zone, the control unit determines the rotation speed of the auxiliary blower a predetermined time before the temperature rise or fall of the compartment. Since it is configured to have a rotation speed, the rotation speed of the auxiliary blower does not change frequently near the set temperature, and in addition to being able to stabilize the cold air circulation amount supplied to the cool air passage by the auxiliary blower. Since the auxiliary blower is not ON-OFF controlled in the dead zone and the temperature fluctuation in the compartment can be suppressed, the temperature control accuracy of the compartment is improved and the compartment temperature is stabilized in the ice temperature storage temperature zone. It will be easier to do.

[Brief description of drawings]

Each drawing shows an embodiment of the present invention. FIG. 1 is a functional block diagram of compartment temperature control, FIG. 2 is a flowchart of software for compartment temperature control of a microcomputer, and FIG. 3 is control. A block diagram of the circuit, FIG. 4 is a schematic side sectional view of the refrigerator, and FIG. 5 is an enlarged sectional view of the rear part of the compartment. (H) ... compartment, (39) ... auxiliary blower, (63) ... compartment temperature detecting means, (73) ... control means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-48-21249 (JP, A) JP-A-59-191868 (JP, A) Actually open Sho-58-74089 (JP, U) Actual-open Sho-58- 76082 (JP, U) Actual opening 47-11655 (JP, U) Actual opening 57-148689 (JP, U)

Claims (1)

[Claims] 1. A compartment having a temperature control device for controlling a compressor and a main blower on the basis of the temperature of a freezer compartment detected by a freezer compartment sensor, and a wall having good heat conductivity formed in a heat-insulating box in a substantially sealed manner. Chamber, a cold air passage formed outside the wall surface in a heat exchange relationship to indirectly cool the compartment, an auxiliary blower for controlling the amount of cold air to the cold air passage, and a compartment sensor for detecting the temperature of the compartment In a refrigerator equipped with, a temperature setting means for setting a set temperature of the compartment and a dead zone for the set temperature, and a rising temperature of the compartment temperature detected by the compartment sensor at predetermined intervals during rising. A control means is provided for controlling the rotation speed of the auxiliary blower every predetermined time so as to increase the rotation speed and decrease the rotation speed while descending, and the control means is provided when the temperature of the compartment is in the dead zone. Is a compartment Refrigerator, characterized in that the rotational speed of the rotational speed of the auxiliary blowers regardless lifting state of temperature was determined before a predetermined time.