JP3483765B2 - Refrigerator control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a refrigerator using a high-intensity DC lamp such as a xenon lamp or a halogen lamp as an interior lamp.

[0002]

Conventionally, a 100V incandescent light bulb has been used as a refrigerator interior light, but since the brightness of this incandescent light bulb is relatively small, it is difficult to sufficiently illuminate the interior. Is in short supply. In addition, since the light of the incandescent light bulb has a yellowish tint, the food stored in the refrigerator is different from the natural color and does not look delicious.

Therefore, it has been considered to use a high brightness DC lamp such as a white light xenon lamp or a halogen lamp. When using this high brightness DC lamp,
Although it is configured to be connected to the DC power supply for the refrigerator's electronic control unit, the high-intensity DC lamp consumes a large amount of current. There is a risk that the output current will be insufficient and the brightness of the high brightness DC lamp will decrease. For this reason,
In order to cope with such a situation, it is necessary to use a DC power source having a large capacity so as not to cause a current shortage, resulting in an increase in cost.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a control device for a refrigerator capable of reliably lighting a high-intensity DC lamp without increasing the capacity of a DC power supply. .

[0005]

Means for Solving the Problems The present invention is provided with a high-intensity direct current lamp for the internal lighting is connected to the DC power source, only setting the load connected to the DC power source, depending on the operation of the refrigerator while connecting the load to the DC power supply Te, when the refrigerator door is opened connects the pre Symbol high intensity DC lamp to the DC power source, contact the DC power to the high intensity DC lamp
When continuing, control means for stopping the energization of the load for a predetermined time is provided (Claim 1).

According to this structure, the control means controls the operation of the refrigerator by connecting the load to the DC power source. Here, when the high-intensity DC lamp is turned on, the control means stops the energization of the load for a predetermined time. As a result, a sufficient current can be supplied to the high-intensity DC lamp, so that the interior of the refrigerator can be sufficiently illuminated by turning on the high-intensity DC lamp. In this case, since the high-intensity DC lamp is lit for a short time, even if the energizing currents of other loads are suppressed for only a short time, the operation of the refrigerator is not hindered.

[0007]

[0008]

[0009]

[0010]

In addition, for lighting the inside of the refrigerator connected to a DC power source.
High brightness DC lamp and load connected to the DC power supply
And connect the load to the DC power supply according to the operation of the refrigerator.
Continued and when the refrigerator door was opened
Control means for connecting the direct current lamp to the direct current power source,
The inrush current of the high-intensity DC lamp exceeds the specified limit current.
An inrush current suppressing circuit for suppressing that the inrush current suppressing circuit connects a collector of a transistor to one end of the DC power source through the high-intensity DC lamp, and an emitter of the transistor through a resistor in the DC power source. The resistor is connected to the other end, and the base of the transistor is connected to a voltage limiter, and the resistor is the high-intensity DC lamp when a predetermined rated current flows in the high-intensity DC lamp in the ON state of the transistor. The resistance value is set so that the rated voltage is applied to the voltage limiter, and the voltage limiter has a limit voltage that matches the base voltage of the transistor in a state where a predetermined limit current flows in the high-intensity DC lamp. May be set (Claims)
2 ).

According to this structure, the control means is
Control refrigerator operation by connecting load to DC power supply
To do. Here, inrush current may flow through the high-intensity DC lamp.
In that case, the inrush current suppression circuit is a high brightness DC lamp.
To prevent the inrush current from exceeding a predetermined control current
The high-brightness DC lamp exceeds the limit current at the start of lighting
A large inrush current does not flow, and the load
Regardless of that DC power supply breaks down
It can be prevented. Further, when the transistor is turned on, the high-intensity DC lamp is connected to the DC power source, so that a rush current flows through the high-intensity DC lamp through the transistor. At this time, when a current larger than the limit current flows through the resistor and the base voltage of the transistor rises above the limit voltage of the voltage limiter, the voltage limiter operates and the base voltage of the transistor is suppressed to the limit voltage. . As a result, when the high-intensity DC lamp is started to be turned on, the inrush current can be suppressed to the limited current, so that the high-intensity DC lamp can be turned on in a short time while preventing an excessive current from flowing.

[0013] Further, for the interior lighting connected to the DC power source
High brightness DC lamp and load connected to the DC power supply
And connect the load to the DC power supply according to the operation of the refrigerator.
Continued and when the refrigerator door was opened
Control means for connecting the direct current lamp to the direct current power source,
The inrush current of the high-intensity DC lamp exceeds the specified limit current.
An inrush current suppressing circuit that suppresses the inrush current suppressing circuit, wherein the inrush current suppressing circuit connects the collector of the transistor to one end of the DC power source through the high-intensity DC lamp and the first resistor, and The resistor is connected to the other end of the DC power source through a resistor 2 and the base of the transistor is connected to a voltage limiter.
And a resistance value of the second resistor is set so that a rated voltage is applied to the high-intensity DC lamp when a predetermined rated current flows in the high-intensity DC lamp while the transistor is on, The voltage limiter may have its limit voltage set so as to match the base voltage of the transistor in a state where a predetermined limit current flows in the high-intensity DC lamp (claim 3 ).

According to the second aspect of the invention, since the resistance connected to the emitter of the transistor bears all of the voltage drop in the steady state, the transistor of the high brightness DC lamp is supplied with a predetermined limiting current. The voltage drop of the resistor connected to the emitter is large, and the base voltage of the transistor becomes high. For this reason, it is necessary to use a resistor with a small resistance value to limit the base current of the transistor, which increases the base current of the transistor in the steady state, increasing the power capacity of the DC power supply for supplying the base current. There is a need to.

However, according to the above configuration, in the steady state, the voltage drop is shared by the first resistor connected to the collector of the transistor and the second resistor connected to the emitter, so that the brightness is high. When the limiting current flows in the DC lamp, the base voltage of the transistor becomes smaller than that in the configuration of claim 2 . As a result, the limit voltage of the voltage limiter connected to the base of the transistor can be set low, and a large resistor can be used as a resistor to limit the base current of the transistor. It becomes smaller, and there is no need to increase the capacity of the DC power supply for supplying the base current.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 schematically shows the electrical configuration of a refrigerator.
In FIG. 1, the voltage doubler rectifier circuit 1 voltage-rectifies 100 V AC from the plug 2 to supply power to the DC power supply 3 and the inverter main circuit 4. The inverter main circuit 4 is mainly composed of switching elements, and drives the compressor 7 by supplying a pulse current to the DC motor 6 in response to the switching elements being turned on and off by the inverter control circuit 5. .

The control circuit 8 (corresponding to load consumption current detecting means and control means) is mainly composed of a microcomputer and operates according to a program stored in the ROM 9. In other words, by driving the compressor 7 through the inverter control circuit 5 based on the temperature detected by the F-room temperature sensor 10, cooler (not shown) generates cool air, and the driver 11 drives D
By driving the C fan 12 (corresponding to the load), the cool air is sent to the freezing compartment (not shown). In addition, the control circuit 8
Drives the damper 15 (corresponding to the load) through the driver 14 based on the temperature detected by the R chamber temperature sensor 13 to blow the cool air generated by the cooler to the refrigerating chamber. Further, the control circuit 8 automatically manufactures ice by driving an ice making machine 17 (corresponding to a load) provided in the freezer through the driver 16. When the door switch 18 that detects that the refrigerator door is opened is turned on, the control circuit 8 causes the driver 19 to drive the xenon lamp 20.
Turn on (equivalent to high brightness DC).

A driver 1 for driving the above loads
1, 14, 16, and 19 are connected to the 14V output terminal of the DC power supply 3, and each load is driven by being connected to the DC power supply 3 through the drivers 11, 14, 16, and 19. In this case, the control circuit 8 is configured to control the energizing current to the load by controlling the drivers 11, 14, 16 and 19.

Here, each of the drivers 11, 14, 1
A shunt resistor 21 is connected to the common energization paths of 6 and 19, and the control circuit 8 detects the consumption current of each load based on the voltage generated across the shunt resistor 21.

Next, the operation of the above configuration will be described. FIG. 2 is a flow chart showing an operation of turning on the xenon lamp 20 among the operations of the control circuit 8, and the operation is performed in parallel with the control (not shown) relating to the operation of another refrigerator. In FIG. 2, the control circuit 8 monitors that the door switch 18 is turned on (S10).
1).

Now, when the user opens the refrigerator door,
Since the door switch 18 is turned on (S101: YES),
The control circuit 8 obtains the current consumption current based on the voltage of the shunt resistor 21 (S102), and adds the rated current (833 mA) of the xenon lamp 20 to the consumption current to consume the xenon lamp 20 at the time of lighting. The current is predicted (S103).

Next, each load (excluding the compressor 7)
After the energization of No. 2 is stopped (S104), the xenon lamp 20 is energized through the driver 19 (S105). This is because, as a characteristic of the xenon lamp 20, as shown in FIG. 3, a rush current that is several times as large as that in a steady state flows at the time of lighting start, and the DC power supply 3 may break down.

Then, after a lapse of 0.5 seconds from the start of lighting the lamp, a steady state is reached (S106: YE
S), when the control circuit 8 predicts that the total current consumption in the lighting state (stable state) of the xenon lamp 20 obtained as described above exceeds the rated output current of the DC power supply 3 (S1
07: YES), so that the total current consumption does not exceed the rated output current of the DC power supply 3 in a state in which the energizing current of each load is suppressed (output reduction), or even if it is stopped, no problem occurs, for example, cold air blowing After carrying out the energization suppressing process for prohibiting the energization of the DC fan 12 for power supply (S108), the energization of other loads is restarted (S109). In this case, if the compressor 7 is stopped, a cooling failure will occur. Therefore, the compressor 7 is not subject to output suppression.

Now, when the user closes the door of the refrigerator,
Since the door switch 18 is turned off (S110: YES),
The control circuit 8 stops the energization of the xenon lamp 20 (S111), and then releases the energization suppression state of each load (S112). As a result, the xenon lamp 20 is turned off and each load is returned to the normal operation state.

According to such an embodiment, when the refrigerator door is opened, the total current consumption is predicted by adding the rated current of the xenon lamp 20 to the current consumption of each load, and the total current consumption is calculated. Is above the rated output current of the DC power supply 3, the energizing current of a predetermined load is suppressed or stopped, so that the xenon lamp 20 is simply energized when the refrigerator door is opened. Compared with the above, the xenon lamp 20 can be reliably turned on. Moreover, since the period during which the energization of each load is controlled is a short time during which the door is open, the operation of each load is not hindered.

Further, since the energization of other loads is stopped for 0.5 seconds at the time of starting the lighting of the xenon lamp 20, even if a large inrush current flows to the xenon lamp 20 at the time of starting the lighting, the DC power supply 3 is turned on. There is no breakdown and system reset.

Furthermore, since the energized state of the compressor 7 is continued even when the energizing current of other loads is suppressed, it is possible to prevent the cooling failure due to the refrigeration cycle from occurring.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is characterized in that the shunt resistor 21 provided in the first embodiment is eliminated.

FIG. 4 shows the entire electrical configuration. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. Only different parts will be described. That is, FIG.
In the ROM 9, the ROM 9 (corresponding to a storage unit) stores the operating state of each load (elapsed time from the start of energization,
In this case, the correspondence relationship between the rotational speed etc.) and the consumption current is stored. When the door switch 18 is turned on, the control circuit 8 stores the consumption stored in the ROM 9 corresponding to the operating state of each load. The current consumption of each load is predicted by reading the current, and the total consumption is obtained by adding the consumption and the rated current of the xenon lamp 20, and the estimated total consumption is the rated output of the DC power supply 3. If it exceeds the current, stop the energization of other loads for 0.5 seconds and then suppress the energizing current of each load so that it does not exceed the rated output current of the DC power supply 3, or energize the load of low priority. When the door switch 18 is turned off, the xenon lamp 20 is energized, the energization of the xenon lamp 20 is stopped, and the energization suppression state of other loads is released.

According to the second embodiment as described above, the relationship between the operating state of each load and the current consumption is stored in the ROM 9 in advance, and is stored in the ROM 9 in correspondence with the operating state of each load. Since the total current consumption in the lighting state of the xenon lamp 20 is predicted by reading the current consumption current of each load that is present, the shunt resistor 21 in the first embodiment can be omitted, and the overall configuration. Can be simplified. In this case, since the ROM 9 for storing data is provided in advance for storing the program of the control circuit 8, it is not necessary to newly provide a storage means.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. In each of the above-described embodiments, the energization of the other loads is stopped for 0.5 seconds when the xenon lamp 20 is started to be lit, but in the third embodiment, the driver 19 of the xenon lamp 20 is lit when the lighting is started. It is characterized in that it has a function of suppressing the inrush current and does not stop the energization of other loads at the time of starting the lighting of the xenon lamp 20.

FIG. 5 shows the driver 19 of the xenon lamp 20.
An example (corresponding to an inrush current suppressing circuit) is shown. In FIG. 5, the emitter of the pnp-type transistor 22 is connected to the 5V output terminal of the DC power supply 3, and is also connected to the output terminal of the control circuit 8 through the series circuit including the resistors 23 and 24. The common connection point of the resistors 23 and 24 is connected to the base of the transistor 22.

The collector of the npn type transistor 25 is connected to the 14V output terminal of the DC power source 3 via the xenon lamp 20, the base of the transistor 25 is connected to the collector of the transistor 22 via the resistor 26, and the emitter of the transistor is connected to the resistor. It is connected to the 0V line via 27. Further, the base of the transistor 25 is connected to the 0V line via the Zener diode 28 having the illustrated polarity.

The rated specification of the xenon lamp 20 used in this embodiment is 12V-833mA ± 8% (10
W). That is, in a steady state, it is necessary to apply 12V to the xenon lamp 20, and a current of 833mA flows in the 12V applied state. Therefore, in the configuration in which the 14V output of the DC power source 3 which is also the power source of another load is commonly used as the power source of the xenon lamp 20, the voltage applied to the xenon lamp 20 becomes 2V due to the voltage drop of the transistor 25 and the resistor 27. Need to bear.

Here, in order to allow a sufficient current of 833 mA or more as a collect current to flow when the transistor 25 is turned on, considering the heat generation of the transistor 25,
The transistor 25 should be used in the saturation region, and the base current should be 20 mA or more to supply Vce of the transistor 25.
Want to suppress the voltage to 0.3V. Therefore, the voltage drop due to the resistor 27 is 1.7 V, and the resistance value of the resistor 27 is 1.7.
From /0.833=2.04, it can be obtained as about 2Ω.

Here, the current limit by the Zener diode 28 is set to 1.5A. Therefore, the resistance 27
Assuming that 1.5 A flows into the transistor 25, the base voltage of the transistor 25 becomes 2 × 1.5 + 0.9 (Vbe of the transistor) =
Since 2 × 1.5 + 0.9 = 3.9 (V), the Zener voltage of the Zener diode 28 becomes 3.9V. That is, when the current flowing through the resistor 27 becomes 1.5 A or more,
Since the Zener diode 28 is turned on and the base voltage of the transistor 25 is limited to 3.9V, the collector current IC is also limited. This allows
Since the inrush current flowing through the xenon lamp 20 is suppressed to 1.5 A, it is possible to light the xenon lamp 20 in a short time while preventing an excessive inrush current from flowing through the xenon lamp 20.

In this case, the base current of the transistor 25 required to supply 1.5 A to the resistor 27 is hfe (min
) = 120, IB = 12.5 (mA), but since the transistor 25 is used in the saturation region, IB is set to 20 mA.

If a Zener current of 5 mA is required to stabilize the Zener diode 28,
It is necessary to flow 25 mA to the resistor 26. Therefore, resistor 2
The value of 6 is (5-3.9-0.1 (Vc of the transistor
e)) / 0.025 = 40 (Ω). At this time, in the steady state of the xenon lamp 20, (5-2 × 0.
A current of 833-0.1-0.9) / 40 = 58 (mA) will flow through the resistor 26.

According to the third embodiment, the xenon lamp 2 is activated when the xenon lamp 20 is turned on.
Since it is possible to light the rush current flowing to 0 for more than 1.5 A in a short time while suppressing the energization of other loads, the DC power source 3 breaks when the xenon lamp 20 starts lighting. It is possible to prevent the system from going down and resetting.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. By the way, in the third embodiment, since 58 mA flows through the resistor 26, it is necessary to use a large capacity 5V output of the DC power source 3 or to increase the rank of the resistor 26. That is, the voltage applied to the xenon lamp 20 in the steady state is 12 V which is the rated voltage of the xenon lamp 20.
Although it is necessary to use a resistor 27 having a large resistance value in order to suppress the above, if the resistance value of the resistor 27 is large,
Zener diode 28 for limiting the current
As a result, it is necessary to use a high Zener voltage (3.9 V in the third embodiment). Therefore, in order to pass a sufficient base current to the transistor 25 when the xenon lamp 20 is started to be turned on, it is necessary to use a resistor having a small resistance value as the resistor 26. However, when the xenon lamp 20 is stationary, the current flows to the resistor 26. Since the current becomes large, it becomes necessary to use a large capacity DC power supply 3 or to increase the rank of the resistor 26.

Therefore, in the fourth embodiment, as shown in FIG. 6, the xenon lamp 20 connected to the collector of the transistor 25 is connected to the DC power source 3 via the first resistor 27a.
And the emitter of the transistor 25 is connected to the second
After being connected to the 0V line via the resistor 27b, the combined resistance of the first and second resistors 27a and 27b is set to match the resistance value of the resistor 27 in the third embodiment. .

According to this structure, when the xenon lamp 20 is stationary, the first and second resistors 27a and 27a are provided.
The xenon lamp 20 due to the voltage drop due to the combined resistance of b
Since the rated voltage of 12 V can be applied to the xenon lamp 20, the xenon lamp 20 can be appropriately turned on and
Since the resistance value of the second resistor 27b is small at the start of lighting of the xenon lamp 20, the Zener voltage of the Zener diode 28 can be suppressed to a low value, and the resistor 26 having a large resistance value can be used. Therefore, since it is possible to suppress the current flowing through the resistor 26 when the xenon lamp 20 is stationary, it is not necessary to use a large capacity DC power source 3 and it is not necessary to increase the rank of the resistor 26.

The present invention is not limited to the above embodiment, but can be modified or expanded as follows. A halogen lamp may be used instead of the xenon lamp 20. The transistor 25 for energizing the xenon lamp 20 may be of the pnp type instead of the npn type. In this case, it goes without saying that the connection relationship between the xenon lamp 20 and the Zener diode 28 is reversed. Instead of the Zener diode 28, a plurality of diodes may be connected in series and the anode side thereof may be connected to the base of the transistor 25.

[0044]

As is apparent from the above description, according to the refrigerator controller of the present invention, the high-intensity DC lamp is turned on.
The current flowing through the load or high-intensity DC lamp
Since the inrush current is suppressed, there is an excellent effect that the high-intensity DC lamp can be reliably turned on without increasing the capacity of the DC power supply.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an electrical configuration in a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the control circuit.

FIG. 3 is a diagram showing a change in current flowing through a xenon lamp.

FIG. 4 is a schematic diagram showing an electrical configuration according to a second embodiment of the present invention.

FIG. 5 is an electric circuit diagram showing a driver for a xenon lamp according to a third embodiment of the present invention.

FIG. 6 is an electric circuit diagram showing a driver for a xenon lamp according to a fourth embodiment of the present invention.

[Explanation of symbols]

3 is a DC power supply, 7 is a compressor, 8 is a control circuit (load consumption current detection means, control means), 9 is a ROM (storage means), 12 is a DC fan (load), 15 is a damper (load), and 17 is ice making. Machine (load), 18 is a door switch, 19
Is a driver (inrush current suppression circuit), 20 is a xenon lamp (high brightness DC lamp), 21 is a shunt resistor, 25 is a transistor, 27 is a resistor, 27a is a first resistor, 27
Reference numeral b is a second resistor, and 28 is a Zener diode (voltage limiter).

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F25D 11/00 101 F25D 29/00

Claims (4)

(57) [Claims] 1. A high-intensity DC lamp for indoor lighting connected to a DC power supply, a load connected to the DC power supply, the load connected to the DC power supply according to the operation of the refrigerator, and a refrigerator When the door is opened, the high-intensity DC lamp is connected to the DC power source, and when the DC power source is connected to the high-intensity DC lamp, control means for stopping energization of the load for a predetermined time is provided. A control device for a refrigerator characterized in that 2. A high-intensity DC lamp for indoor lighting connected to a DC power supply, a load connected to the DC power supply, the load connected to the DC power supply according to the operation of the refrigerator, and a refrigerator Control means for connecting the high-intensity DC lamp to the DC power supply when the door is opened, and an inrush current suppressing circuit for suppressing the inrush current of the high-intensity DC lamp from exceeding a predetermined limit current. The inrush current suppressing circuit connects the collector of the transistor to one end of the DC power supply through the high-intensity DC lamp, connects the emitter of the transistor to the other end of the DC power supply through a resistor, and connects the base of the transistor to a voltage. The resistor is connected to the high brightness DC lamp when a predetermined rated current flows in the high brightness DC lamp with the transistor turned on. The resistance value is set so that the rated voltage is applied to the DC lamp, and the voltage limiter has its limit so as to match the base voltage of the transistor in the state where a predetermined limiting current flows in the high-intensity DC lamp. A control device for a refrigerator characterized in that a voltage is set. 3. A high-intensity DC lamp for indoor lighting connected to a DC power supply, a load connected to the DC power supply, the load connected to the DC power supply according to the operation of the refrigerator, and a refrigerator Control means for connecting the high-intensity DC lamp to the DC power supply when the door is opened, and an inrush current suppressing circuit for suppressing the inrush current of the high-intensity DC lamp from exceeding a predetermined limit current. The inrush current suppressing circuit connects the collector of the transistor to one end of the DC power source through the high-intensity DC lamp and the first resistor, and connects the emitter of the transistor to the second end.
Is connected to the other end of the DC power source through the resistor, and the base of the transistor is connected to a voltage limiter. The first and second resistors are connected to the high-intensity DC lamp when the transistor is on. The resistance value is set so that a rated voltage is applied to the high-intensity DC lamp when the rated current of the high-intensity DC lamp flows, the voltage limiter, in the state where a predetermined limiting current flows in the high-intensity DC lamp. A control device for a refrigerator, wherein the limit voltage is set so as to match the base voltage of the transistor. 4. The control device for the refrigerator according to claim 2, wherein the voltage limiter is a Zener diode.