JPH0351989B2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a refrigerator having a specification switching chamber.

[Technical Background of the Invention and Problems Therewith] In recent years, refrigerators have been provided that have specification switching compartments in addition to the freezing compartment and the refrigerator compartment. The setting can be switched to one of the refrigerator compartment specifications. There are various configurations for maintaining the temperature condition corresponding to the specifications that have been switched.One example is a first structure with a large flow path area on the back of the specification switching chamber. A cold air outlet and a second cold air outlet having a small flow path area are formed, the first cold air outlet is provided with a first damper, and the second cold air outlet is provided with a second damper and a second cool air outlet. 2. Specification switching of the damper drive control circuit When a room temperature sensor and a heater are installed and the freezer compartment specification is set by operating the freezer compartment specification selection switch, the first cold air outlet is opened by the manual damper based on that operation. Then, the amount of cold air supplied is increased to obtain a low temperature specified by the freezer compartment. Further, when the refrigerator compartment specification is set based on the operation of the refrigerator compartment specification selection switch, the first damper is closed, and the temperature detection value from the specification switching room temperature sensor and the refrigeration temperature reference value are set. The opening and closing of the second damper is controlled to obtain a temperature condition according to the specifications of the refrigerator compartment. Furthermore, when the chilled room specification is set based on the operation of the chilled room specification selection switch, the first damper is closed and the specification switching room temperature sensor is heated by the heater to increase the detected temperature of the specification switching room temperature sensor. The temperature is set to be higher than the actual temperature of the specification switching room, and the temperature state of the chilled room specification, which is lower than that of the refrigerator room specification, is obtained based on the temperature detection value from the specification switching room temperature sensor and the refrigeration temperature reference value.

However, in this case, there is a problem in that the specification switching chamber, which should originally be cooled, is heated by the heater for heating the specification switching room temperature sensor, and the following configuration has been considered as a solution to this problem.
That is, in order to eliminate the need for a heater for heating the specification switching room temperature sensor, a chilled temperature reference value was set in addition to the refrigeration temperature reference value as the temperature reference value in the second damper drive control circuit, and the refrigerator room specification was set. When the temperature detection value from the specification switching room temperature sensor and the refrigeration temperature reference value are set, the damper control is performed, and when the chilled room specification is set, the damper control is performed based on the temperature detection value and the chilled temperature reference value. do.

However, in any of the above configurations, the specification switching room temperature sensor is arranged as a unit with the damper (second damper), so the specification switching room temperature sensor is normally placed on the back wall of the specification switching room. As the outside temperature (outside air temperature) decreases, the specifications of the specification switching room will change. There was a problem in that the actual internal temperature became lower than the temperature detected by the specification switching room temperature sensor, and as a result, the temperature became lower than the appropriate temperature for the refrigerator room specification or chilled room specification to which the specification switching room was set.

[Object of the Invention] The object of the present invention is to operate the specification switching room appropriately according to the set specifications, regardless of changes in the outside temperature, on the premise that the heater for heating the specification switching room temperature sensor can be made unnecessary. To provide a refrigerator that can maintain a constant temperature state.

[Summary of the Invention] The present invention provides a specification switching chamber that can be switched to one of the freezer compartment specifications, chilled compartment specifications, and refrigerator compartment specifications, a damper device that adjusts the amount of cold air supplied to the specification switching chamber, and It has a specification switching room temperature sensor that detects the temperature of the specification switching room, and when the specification switching room is set to at least one of the chilled room specification and the refrigerator room specification, the temperature detected by the specification switching room temperature sensor and the chilled temperature reference value or It has a drive control circuit that drives and controls the damper device based on the refrigeration temperature reference value, and an outside temperature sensor that detects the outside temperature of the refrigerator, and controls the chilled temperature of the drive control circuit based on the temperature detected by the outside temperature sensor. It is equipped with a temperature compensation circuit that changes the reference value and the refrigeration temperature reference value, so that when the specification switching room is set to the refrigerator room specification or the chilled room specification, the temperature control is changed from the conventional specification switching room sensor heating. This can be done without using a heater, and the refrigeration temperature reference value and chilled temperature reference value are changed in accordance with changes in the outside temperature.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. First, in FIG. 2, reference numeral 1 denotes a refrigerator main body, in which a freezing chamber 2, a specification switching chamber 3, and a refrigerating chamber 4 are formed. Each of these chambers 2, 3, and 4 is supplied with cold air from a cooler chamber (not shown) through a duct, and in particular, one duct communicates with the specification switching chamber 3. A damper device for opening and closing the cold air outlet of this duct is provided on the back wall of the switching chamber 3 together with a specification switching room temperature sensor 9 (see FIG. 1).
This damper device is driven by an electromagnetic solenoid. 5, 6, and 7 are switches arranged on the front of the refrigerator body. Switch 5 is for selecting the freezer compartment specification, switch 6 is for selecting the chilled compartment specification, and switch 7 is for selecting the refrigerator compartment specification. 5, 6 and 7 consist of triple lock type push button switches. Therefore, when any one of the switches 5 to 7 is turned on, the other switches are returned to the off position. Next, in Figure 1,
8 is a drive control circuit, which will be described below.
Reference numeral 9 denotes the specification switching room temperature sensor described above, which is composed of a negative characteristic thermistor. The specification switching room temperature sensor 9 and the voltage dividing resistor 10 are connected in series between the DC power supply terminal Vcc and the ground to form a detection voltage generation circuit 11. The detected voltage corresponding to the resistance change accompanying the temperature change in the 9 parts is outputted from the output terminal 11a as the temperature detection value V _11. Therefore, as the temperature detected by the specification switching room temperature sensor 9 becomes lower, the temperature detection value V ₁₁ increases. becomes lower. 12 is a reference voltage generation circuit, which has voltage dividing resistors 13, 14, 15, 16, and 17, and voltage dividing resistors 13 and 14 are connected in series between the DC power supply terminal Vcc and the ground. Then, the voltage dividing resistor 15 is replaced by an NPN type transistor 18.
The voltage dividing resistor 16 is grounded through a transistor 40 which will be described later, and the voltage dividing resistor 17 is grounded through a transistor 42 which will be described later.
This reference voltage generation circuit 12 has a voltage dividing resistor 13 which is a reference voltage output terminal 12a and a voltage dividing resistor 1.
It outputs a reference voltage from the common connection point with 4 to 17, and when the refrigerating room specification is selected and set, the reference voltage is used as the refrigerating temperature reference value Vr,
When the chilled room specification is selected and set, each is output as the chilled temperature reference value Vc. The base of the transistor 18 is connected via a resistor 18a to a common connection point between the chilled room specification selection switch 6 and the pull-down resistor 6a. 19 is a comparator whose non-inverting input terminal (+) is connected to the detection voltage output terminal 11a of the detection voltage generation circuit 11.
The inverting terminal (-) is connected to the reference voltage output terminal 12a of the reference voltage generation circuit 12,
The output terminal is connected to one input terminal of the OR circuit 20. Note that 21 is a feedback resistor for providing hysteresis. The other input terminal of the OR circuit 20 is connected to a common connection point between the freezer compartment specification selection switch 5 and the pull-down resistor 22. Reference numeral 23 denotes a relay coil for turning on and off a power-on/off switch for the damper device (not shown), which is connected between the DC power supply terminal Vcc and the ground via an NPN type transistor 24. is connected to the output terminal of the OR circuit 20 via the resistor 24a. When the output terminal of the OR circuit 20 becomes high level, the relay coil 23 is energized by turning on the transistor 24 and drives the damper device to open. In contrast to the drive control circuit 8 described above, 25 is a temperature compensation circuit, which will be described below. Reference numeral 26 denotes an external temperature sensor consisting of a negative characteristic thermistor disposed outside the refrigerator main body 1;
The outside temperature sensor 26 and the voltage dividing resistor 27 are connected in series between the DC power supply terminal Vcc and ground to form an outside temperature detection circuit 28. The outside temperature detection circuit 28 outputs a detected voltage from its detection voltage output terminal 28a as an outside temperature detection value V ₂₈ in response to a change in the resistance value of the outside temperature sensor 26 due to a change in outside temperature. 29 is voltage dividing resistor 30 and voltage dividing resistor 31
is connected between the DC power supply terminal Vcc and the ground, and this circuit outputs the reference voltage as the first external temperature reference value _V29 from its reference voltage output terminal 29a. . 32 is voltage dividing resistor 3
3 and a voltage dividing resistor 34 are connected between the DC power supply terminal Vcc and the ground _.
The voltage is output from the reference voltage output terminal 32a. In this case, the first outside temperature reference value V ₂₉ is
It is set to be larger than the outside standard value V ₃₂ (V ₂₉ > V ₃₂ ). 35 and 36 are comparators, respectively, the non-inverting input terminal (+) of each comparator 35 and 36 is connected to the detection voltage output terminal 28a of the outside temperature detection circuit 28, and the inverting terminal (-) of the comparator 35 is connected to the detection voltage output terminal 28a of the outside temperature detection circuit 28. connected to the reference voltage output terminal 29a of the first reference voltage generation circuit 29;
The inverting terminal (-) of the comparator 36 is connected to the reference voltage output terminal 32a of the second reference voltage generation circuit 32. Further, the output terminal of the comparator 35 is connected to one input terminal of an AND circuit 38 via an inverter circuit 37, and also to one input terminal of an AND circuit 39. Further, the output terminal of the comparator 36 is connected to the other input terminal of the AND circuit 38 and to the other input terminal of the AND circuit 39. Reference numeral 40 denotes an NPN type transistor serving as a switching element for the voltage dividing resistor 16, and its base is connected to the output terminal of the AND circuit 38 via a resistor 41. 42 is the voltage dividing resistor 1
This is an NPN type transistor serving as a switching element for 7, and its base is connected to the output terminal of the AND circuit 39 via a resistor 43.
Here, the resistance value R 16 of the voltage dividing resistor ₁₆ and the voltage dividing resistor 17
The relationship with the resistance value R ₁₇ is set so that R ₁₆ > P ₁₇ .

Now, to explain the operation of the above configuration, first, when the freezer compartment specification selection switch 5 is turned on, a high level signal is given to the other input terminal of the OR circuit 20. Outputs a high level signal from the 19 output terminals regardless of the signal given to one input terminal,
As a result, the relay coil 2 is energized by turning on the transistor 24, and the damper device is driven to open the cold air outlet of the specification switching chamber 3.
As a result, cold air is constantly supplied to the interior of the specification switching chamber 3, and the specification switching chamber 3 is maintained at a temperature according to the specifications of the freezer compartment.

Next, when the refrigerator compartment specification selection switch 7 is turned on, the chilled compartment specification selection switch 6 is turned off, so that the transistor 18 is also turned off, and as a result, the voltage dividing resistor 15 is disabled. Therefore, in this case, the refrigeration temperature reference value Vr, which is the reference voltage in the reference voltage generation circuit 12, is determined by the voltage dividing resistor 13.
and the voltage dividing resistors 14, 16, and 17. Here, the voltage dividing resistors 16 and 17 are enabled/disabled by the temperature compensation circuit 25. For example, when the outside temperature is relatively high, the outside temperature detection circuit 28 in the temperature compensation circuit 25 The temperature detection value V ₂₈ outputted from is the first external temperature reference value outputted from the first reference voltage generation circuit 29.
V ₂₉ and the second external temperature reference value V ₃₂ output from the second reference voltage generation circuit 32,
As a result, the outputs of the comparators 35 and 36 become high level, thereby the output of the AND circuit 38 becomes low level, and the output of the AND circuit 39 becomes high level. Therefore, the transistor 40
is in the off state and the voltage dividing resistor 16 is disabled,
Further, the transistor 42 is turned on and the voltage dividing resistor 17 is enabled. As a result, the refrigeration temperature reference value Vr in the reference voltage generation circuit 12 becomes the first refrigeration temperature reference value Vr ₁ determined by the voltage dividing resistor 13 and the voltage dividing resistors 14 and 17. In addition, when the outside temperature is medium, the outside temperature detection circuit 2
The outside temperature detection value V ₂₈ output from the comparator 3 is smaller than the first outside temperature reference value V ₂₉ and larger than the second outside temperature reference value V ₃₂ .
The output of the comparator 36 is at a low level, and the output of the comparator 36 is at a high level.
The output of the AND circuit 39 is at a high level, and the output of the AND circuit 39 is at a low level, thereby turning off the transistor 42 and turning on the transistor 40, disabling the voltage dividing resistor 17 and enabling the voltage dividing resistor 16. Ru. As a result, the refrigeration temperature reference value Vr becomes the second refrigeration temperature reference value Vr ₂ determined by the voltage dividing resistor 13 and the voltage dividing resistors 14 and 16. The second refrigeration temperature reference value Vr ₂ at this time is the resistance value R ₁₆ of the voltage dividing resistor 16 and the resistance value of the voltage dividing resistor 17.
Since the relationship with R ₁₇ is R ₁₆ > R ₁₇ , Vr ₂ > Vr ₁ , and thus the refrigeration temperature reference value Vr is changed to be higher. Furthermore, when the outside temperature is low, the outside temperature detection value V ₂₈ by the outside temperature detection circuit 28 is smaller than the first outside temperature reference value V ₂₉ and the second outside temperature reference value V ₃₂ , As a result, the outputs of comparators 35 and 36 are both at low level, transistors 40 and 42 are both turned off, and voltage dividing resistor 16 and voltage dividing resistor 17 are both disabled.
Therefore, the refrigeration temperature reference value Vr in the reference voltage generation circuit 12 becomes the third refrigeration temperature reference value Vr ₃ determined by the voltage dividing resistor 13 and the voltage dividing resistor 14, and this third refrigeration temperature reference value Vr ₃ is higher than the second refrigeration temperature reference value Vr ₂ . As you can see from the above,
As the outside temperature decreases, the refrigeration temperature reference value Vr is changed sequentially, so as a result, the detected temperature value
The reversal operating point of the comparator 19, which operates based on V ₁₁ and the refrigeration temperature reference value Vr, increases as the outside temperature decreases, and as a result, the outside temperature becomes lower and the actual temperature in the specification switching chamber 3 changes to the specification switch. If the temperature becomes lower than the temperature of room temperature sensor 9, relay coil 2
The drive operating temperature of No. 3 can be increased, and therefore,
The specification switching chamber 3 will not be in a supercooled state, and an appropriate temperature state according to the specifications of the refrigerator compartment can be obtained.

Next, when the chilled room specification selection switch 6 is turned on, the transistor 18 is turned on.
The voltage dividing resistor 15 is enabled and the reference voltage of the reference voltage generating circuit 12 is determined by the voltage dividing resistor 13 and the voltage dividing resistors 14, 15, 16 and 17 at the chilled temperature. It is output as the reference value Vc. However, in this case as well, the chilled temperature reference value Vc is changed by the temperature compensation circuit 25 according to the temperature outside the refrigerator. That is, when the temperature outside the refrigerator is relatively high, the chilled temperature reference value Vc is changed by the voltage dividing resistor 1.
3 and the voltage dividing resistors 14, 15, and 17, and the _first chilled temperature reference value Vc is determined by the voltage dividing resistor 13, The temperature is changed to a second chilled temperature reference value Vc ₂ determined by voltage dividing resistors 14, 15 and 16. In this case, the second chilled temperature reference value Vc ₂ is the first chilled temperature reference value
When Vc is greater than ₁ and the outside temperature is low,
The chilled temperature reference value Vc is changed to a third chilled temperature reference value Vc ₃ determined by the voltage dividing resistor 13 and the voltage dividing resistors 14 and 15. In this case, this third chilled temperature reference value Vc ₃ is greater than the second chilled temperature reference value Vc ₂ . As a result,
In the case of this chilled room specification, even if the outside temperature becomes low, the specification switching chamber 3 will not be in a supercooled state, and an appropriate temperature state according to the chilled room specification can be obtained.

In this way, according to this embodiment, the drive control circuit 8
The refrigeration temperature reference value is supplied to the reference voltage generation circuit 12 in
Vr and the chilled temperature reference value Vc can be switched and set, and when the refrigerating room specification is selected and _set , the damper device When the chilled room specification is set, the damper device is driven and controlled based on the chilled temperature reference value Vc and the temperature detection value _V11 , unlike in the conventional case. It is possible to eliminate the need for a heater for heating the specification switching room temperature sensor in room specifications, and as a result, the adverse effects of the heater can be eliminated. Furthermore, since the refrigeration temperature reference value Vr and the chilled temperature reference value Vc outputted from the reference voltage generation circuit 12 in the drive control circuit 8 are changed by the temperature compensation circuit 25 according to the outside temperature, the temperature outside the refrigerator is changed. According to temperature changes, the specification switching chamber 3 can be controlled to an appropriate temperature state according to the set specifications.

[Effects of the Invention] As is clear from the above description, the present invention not only makes it possible to eliminate the need for a heater for heating a specification switching room temperature sensor in a device having a specification switching chamber, but also enables the invention to be used regardless of changes in outside temperature. First, an excellent effect is achieved in that the specification switching chamber can be maintained at an appropriate temperature according to the set specifications.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, with FIG. 1 being an electric circuit diagram and FIG. 2 being a front view of the entire refrigerator. In the figure, 3 is a specification switching chamber, 5 is a switch for selecting freezer compartment specifications, 6 is a switch for selecting chilled compartment specifications, 7 is a switch for selecting refrigerator compartment specifications, 8 is a drive control circuit, and 9 is a specification switching room temperature. Sensor, 12 is a reference voltage generation circuit, 19 is a comparator, 23 is a relay coil, 25 is a temperature compensation circuit, 26 is an outside temperature sensor, 29 is a first reference voltage generation circuit, 33 is a second reference voltage generation circuit , 35 and 36 are comparators, respectively.

Claims (1)

[Claims] 1. A specification switching room that can be switched to either the freezer room specification, the chilled room specification, or the refrigerator room specification;
It has a damper device that adjusts the amount of cold air supplied to the specification switching room, and a specification switching room temperature sensor that detects the temperature of the specification switching room, and the specification switching room is set to at least one of the chilled room specification and the refrigerator room specification. The damper device includes a drive control circuit that drives and controls the damper device based on the temperature detected by the specification switching room temperature sensor and the chilled temperature reference value or the refrigeration temperature reference value in the specified state, and an outside temperature sensor that detects the outside temperature of the refrigerator. A refrigerator comprising: a temperature compensation circuit that changes a chilled temperature reference value and a refrigerated temperature reference value of the drive control circuit based on a temperature value detected by an outside temperature sensor.