JPH049577A - Vaporization control device for refrigerator - Google Patents

Abstract

PURPOSE:To maintain a higher reliability vaporization power and prevent bedewing on the bottom of a refrigerator under high load time when door opening/closing are frequently carried out or under such a condition where the door is often left open forgetfully by driving a vaporization promotion blower which is synchronized with a rotary type compressor when a measured estimation time of continuous 'opening' time of a damper exceeds a specified time. CONSTITUTION:At the point of time when a specified time has arrived, an 'H' signal is arranged to be generated continuously to an AND circuit 26 until the completion of the next defrosting time. On the other hand, when a rotary type compressor 6 is operating, the 'H' signal is transmitted from an 'a' terminal of a defrost control device while an 'L' signal is transmitted into the AND circuit 26 when the compressor 6 is not driving. The output of the AND circuit 26 turns into an 'H' signal by the 'H' signal from a timer 25 and the 'H' signal from the defrost control device 16 (which means the in-operation of the rotary type compressor 6.). As a result, a transistor 27 is turned ON, thereby conducting a relay coil 28, closing a relay contact 29, and driving a vaporization promotion blower 30.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an evaporation control device for a refrigerator that forcibly evaporates defrosting water.

Conventional technology Recent trends in refrigerators include the trend toward larger capacity refrigerators, which are installed in the same way as before. Therefore, as a means of increasing volumetric efficiency, small-sized rotary compressors are increasingly being adopted as compressors for refrigeration cycles.

For example, there is the NR-D37V1 released by Matsushita Electric Industrial Co., Ltd. in April 1989. This conventional configuration will be described below. Although the NR-D37v1 has four doors, the main points will be explained with reference to FIGS. 6 and 6 using a two-door diagram.

Reference numeral 1 denotes a refrigerator main body, which is divided into a freezer compartment in the upper part and a refrigerator compartment 4 in the lower part by a partition wall 2. 6 is the machine room,
It is provided on the bottom surface of the refrigerator main body 1. 6 is a rotary compressor, which is provided in the machine room 6. or,
7 is a cooler, and 8 is a blower for forcing the cold air cooled by the cooler 7 into the freezer compartment 3 and the refrigerator compartment 4.

In addition, 9 is a drain pipe (not shown) for discharging the defrosting water from the cooler 7.
This is a defrost water receiving tray. 10 is a heating plate on which the defrosting water tray 9 is placed and evaporates the defrosting water;
Reference numeral 1 denotes a heating pipe led from a rotary compressor e also installed in the machine room 6 and integrally fixed to the heating plate 10.

Next, the electric circuit diagram and control circuit will be explained. The rotary compressors 6 and 8 are connected in parallel, connected in series with a relay contact 12, and then connected to a power source.

Reference numeral 13 denotes a temperature control device for the freezing room, a comparison circuit including a temperature detector 14 provided in the freezing room, resistors R1p R2+ R3, and a comparator 16, and a defrosting control device for measuring the accumulated time of the rotary compressor 6. 16, a transistor 17, and a relay coil 18, and the output of the comparator 15 is input to the defrosting control device 16. The a terminal of the defrosting control device 16 is connected to the base of the transistor 17. Further, an attraction relay coil 18 for opening and closing the relay contact 12 is connected to the collector of the transistor 17. A bimetal 19 detects the defrosting end temperature during defrosting, and is connected to the input of the defrosting control device 16.

Further, the b terminal of the defrosting control device 16 is connected to the transistor 2.
connected to the base of o. Further, the transistor 2
A suction relay coil 22 for opening and closing a relay contact 21 is connected to the collector 0. 23 is a defrosting heater (not shown) which is energized by opening and closing of the relay contact 21.

In such a configuration, when the temperature inside the freezing compartment 3 is higher than a predetermined value, the resistance value RTH1 of the temperature detector 14 of the freezing compartment becomes small, and is determined by this resistance value RTH1 and the resistance R1. The output of the comparator 15 whose potential at point A is higher than the potential at point B determined by resistors R2 and R3 is
The defrosting control device 16 receives the output “H” from the comparator 16.
Upon receiving the signal, the a terminal also becomes “Hl” and the transistor 17
is turned on, and the relay coil 18 becomes conductive. Then, the relay contact 12 closes, and the rotary compressor 6 and the blower 8
is operated to cool the freezer compartment 3 and the refrigerator compartment 4. After that, when the inside of the freezer compartment 3 is cooled to a predetermined temperature, the freezer compartment 3
The resistance value RTH1 of the temperature sensor 14 inside increases, and the A potential becomes smaller than the B potential, so the comparator 16 becomes LO.
W (hereinafter referred to as @L) signal is generated, the a terminal of the defrosting control device 16 receives the Ill L j signal, and the output to the transistor 17 is "L", and the transistor 17d, 0FFI Then, conduction to the relay coil 18 is cut off, the relay contact 12 is opened, and the rotary compressor 6 and the blower 8 are stopped.

Next, the operation of the defrosting control device 16 will be described. The defrosting control device 16 measures the ``H1 signal'' of the comparator 16, that is, the operation time of the rotary pressure age,
When a predetermined cumulative time (for example, 10 hours) is reached, the signal to the transistor 17 becomes L1, conduction to the υ relay coil 18 is cut off, the relay contact 12 is opened, and the rotary compressor 6 At the same time, when the blower 8 stops, the b terminal of the defrost control device 16 outputs "Hl", the transistor 2o conducts the ONL relay coil 22, closes the relay contact 21, and energizes the defrost heater 23. Defrosting is started.When the bimetal 19 reaches a predetermined temperature, the contact of the bimetal 19 becomes 0FFL.The output to the transistor 2o of the defrosting control device 16 becomes "L", and conduction to the relay coil 22 is interrupted. The defrosting heater 23 is cut off, and the power to the defrosting heater 23 is turned off, thereby completing defrosting.

At this time, the temperature inside the freezer compartment 3 is higher than the predetermined value because it has been defrosted, and the potential at point A determined by this resistance value RTH1 and resistor R1 is determined by resistor R2°R3. The output of the comparator 16 becomes lH' and is input to the defrosting control device 16. A terminal (d, to the transistor 17) of the defrosting control device 16
H'' signal is generated, the transistor 17 is turned on, the relay coil 18 is made conductive and the relay contact 12 is closed, the rotary compressor 6 and the blower 8 are operated again, and the defrosting control device 16 is cleared to zero. , the operating time of the rotary compressor 6 is measured again.

Problems to be Solved by the Invention However, such a configuration has the following problems.

(1) Downsizing of the rotary compressor improves the volumetric efficiency of the refrigerator body and reduces the space required to install the refrigerator, but the space inside the machine room that houses the rotary compressor is It was narrow, air convection decreased, and the ability to evaporate the defrost water accumulated in the defrost water tray was significantly degraded.

Especially when the door is opened and closed frequently, or under conditions such as forgetting to close the door, the evaporation capacity decreases significantly.
Under such conditions, there was a high risk that the defrosting water would overflow from the defrosting water tray and wet the floor, etc.

? ) Also, as mentioned above, since the air convection in the machine room is reduced, the bottom of the refrigerator, that is, the upper part of the defrost water tray, is filled with warm and humid water, resulting in dew condensation.

In view of the above-mentioned problems, the present invention has been developed to ensure more reliable evaporation capacity under conditions such as when the door is frequently opened and closed under high load, or under conditions such as forgetting to close the door. The purpose is to prevent condensation in

Means for Solving the Problems In order to solve the above problems, the evaporation control device of the present invention includes:
When the cooling load increases, the amount of frost on the cooler increases and the resistance to cold air passage increases, which reduces the amount of cold air circulating inside the refrigerator and reduces the heat exchange efficiency of the cooler. The damper, which is used to adjust the temperature appropriately, takes advantage of the phenomenon that the damper is in the open state, and the damper is continuously operated.
If the accumulated time of one hour of opening is exceeded, the evaporation promoting fan is operated in synchronization with the rotary compressor.

Operation The present invention determines that the amount of frost on the cooler is large when the accumulated time of the continuous "open" time of the damper exceeds a certain predetermined set value by the above-described control, and at that point Since the evaporation-promoting blower is operated in synchronization with the next operation of the frontage transfer compressor for the defrosting cloth, sufficient convection can be obtained in the machine room and the evaporation capacity can be secured.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 4. In addition, the same reference numerals are used for the same configuration as before.
A detailed explanation thereof will be omitted and only different parts will be described.

37, the cold air cooled by the cooler 7 is sent to the refrigerator compartment 4 by the blower 8.
At the entrance of the refrigerator compartment 4, there is a damper thermostat 38 (hereinafter referred to as a damper thermostat 38) that adjusts the amount of cold air flowing in according to electrical input.
is provided. To explain the details of the electric damper 38, 39 is a solenoid, and 4o is a damper operated by the solenoid 39 to open and close the cold air passage. 41
is a damper cane, which has an air passage section 42 in the upper part and a mechanical part 43 in the lower part. Reference numeral 44 denotes a rod that pushes up the damper 40 in the opening direction, which passes through a part of the damper cane 41 and communicates with the air passage section 42 and the mechanical section 43, and connects its tip to the damper whose upper end is pivotally supported by the air passage section 42. It is in contact with a part of the lower surface of 40. A plunger 46 is connected to the rod 44 and is inserted into the inner core of the solenoid 39 housed in the mechanical part 43 to move up and down. A spring 46 normally biases the plunger 45 downward. Further, 47 is a spring that biases the damper 40 in the closing direction. Next, 48 is a control panel that accommodates the electric damper 40, and the control panel 48 is provided with a cold air discharge air passage 5o formed of a heat insulating material.

Further, 32 is a temperature sensor such as a thermistor provided in the refrigerator compartment 4.

Next, the control circuit will be explained.

Freezer compartment control device 13 is the same as the conventional example.

24 is an evaporation control device, which includes a timer 26, an AND circuit 26. ) A transistor 27 and a relay coil 28 are provided, and the outputs of the terminals of the defrosting control device 24 are input to the AND circuit 26 and the timer 25, respectively.

Further, the output of the b terminal of the defrosting control device 24 is input to the timer 25.

The output of the timer 25 is input to the other side of the AND circuit 26, and the output of the AND circuit 26 is
It is connected to the base of the transistor 27. A suction relay coil 28 for opening and closing the relay contact 29 is connected to the collector of the transistor 2. Reference numeral 30 denotes an evaporation-promoting blower installed in the machine room, which is connected in series with the relay contact 29 and in parallel with the rotary compressor 6.

31 is a refrigerating room temperature control device, which includes a temperature detector 32 such as a thermistor, resistors R4, Rs, Re, and a controller 33.
The output of the comparator 33 is connected to the base of the transistor 34, and the collector of the transistor 34 is connected to the renoid of the electric damper 38 in the refrigerator compartment 4. A relay coil 35 is connected in order to make 39 conductive. The other power of the refrigerator room temperature control device 31 is input to the timer 25.

In this case, regarding the temperature control of the refrigerator compartment 4, when the temperature inside the refrigerator compartment 4 is higher than a predetermined value, the resistance value RIH2 of the temperature sensor 32 of the refrigerator compartment 4 becomes smaller and the resistance value RTH2 and the resistance value become smaller. The output of the comparator 33, in which the potential at the 0 point determined by the value R4 is υ higher than the potential at the D point determined by the resistors Rs and Rs, becomes "Hl", so the transistor 34 is turned on. conducts,
Since the relay contact 36 is closed and the renoid 39 of the electric damper 38 is conductive, the damper 40 is opened and the refrigerator compartment 4 is closed.
Cold air flows inside and is cooled. After that, when the temperature inside the refrigerator compartment 4 is cooled to a predetermined temperature, the resistance value RTH2 of the temperature sensor 32 inside the refrigerator compartment 4 increases, and the C potential becomes smaller than the D potential, so the output of the comparator 33 becomes ,1
The transistor 34 turns OFF.Then, the conduction to the relay coil 36 is cut off, and the damper 40 closes to prevent the cold air from flowing into the refrigerator compartment 4.The above actions are repeated to complete the refrigerator. Refrigerate temperature range (0 to 10
℃).

Next, the operation of the evaporation control device 24 will be described.

The timer 26 is configured by the defrosting control device 16 to open the damper 40 of the electric damper 38 continuously after a predetermined cumulative operating time of the rotary compressor 6 (for example, 6 hours). Accumulated time (e.g. 3 hours)
is measured by the output from the refrigerator room temperature control device 31.

Then, when the predetermined time is reached, A
The "H" signal continues to be generated to the ND circuit 26 until the next defrosting is completed. On the other hand, when the rotary compressor 6 is operating, the "H1 signal" is output from the terminal of the defrosting control device.
When the vehicle is not in operation, an "L" signal is input to the AND circuit 26. Here, the output of the AND circuit 26 is
6 and the “H” signal from the defrosting control device 16.
” signal (that is, rotary compressor 3 is in operation) and 1
The H1 signal is generated, the transistor 27 is turned on, the relay coil 28 is made conductive, the relay contact 29 is closed, and the evaporation promoting fan 30 is operated. Further, the defrosting control device 16
When the signal from the timer 26 is "L" (that is, the rotary compressor 6 is stopped), the 8-power of the AND circuit 26 is equal to "L'" and the transistor 2, regardless of whether the signal from the timer 26 is "H".
7[0FFl, the relay coil 28 is cut off, the relay contact 29 is opened, and the evaporation promoting fan 30 stops operating.

The above operations are repeated until the next bimetal 19 detects the end of defrosting.

On the other hand, regarding the measurement of the cumulative time of continuous opening of the damper 40 of the electric damper 38 for one hour, at a predetermined point in time, the "H" signal continues to be generated, and at the same time, it is cleared to zero, and the rotary compressor 6 is turned on again. Measurement is performed after the cumulative time (for example, 5 hours).

As described above, the timer 25 measures the accumulated time of one hour of continuous open operation of the damper 40 of the mechanical damper 38, and if it exceeds the predetermined set value (for example, 3 hours), it will stick to the cooler 7. It is determined that the amount of frost formed is large, and the amount of defrost water in the defrost water tray 9 increases compared to normal times. In synchronization with the operation of the rotary compressor 6, it is operated until the end of the next defrosting to force convection inside the machine room 5, which increases the evaporation capacity more than before and prevents condensation on the bottom of the refrigerator. It can also be prevented.

Effects of the Invention As described above, the present invention includes a defrosting control device that starts defrosting when the operating time of the rotary compressor is accumulated for a predetermined time, and ,
A timer measures the accumulated time of one continuous hour of electric damper operation, and if the time exceeds a predetermined set value, the evaporation-promoting blower installed in the machine room is switched to operate the rotary compressor. Since this is an evaporation control device that operates synchronously until the end of the next defrost, it not only increases the evaporation capacity under conditions where a large amount of defrost water accumulates, but also because it creates forced convection in the machine room. It can also prevent condensation on the bottom of the refrigerator.

[Brief explanation of the drawing]

Fig. 1 is a control circuit diagram and electric circuit diagram of a refrigerator showing an embodiment of the present invention, Fig. 2 is a sectional view of the same refrigerator, Fig. 3 is an enlarged view of main parts of the refrigerator in Fig. 2, and Fig. 4 The figure is a front view of the machine room of the refrigerator, FIG. 6 is a control circuit diagram and electric circuit diagram of a conventional refrigerator, and FIG. 6 is a sectional view of the conventional refrigerator. 6...Rotary compressor, 7...Cooler,
8...Blower, 9...Defrost water tray, 1
6... Defrost control device, 24... Evaporation control device, 3o... Evaporation promoting blower, 4o...
...Name of dumper's agent: Patent attorney Shigetaka Awano and one other person required
Tan 80 - 旙

Claims (1)

[Claims] A rotary compressor, a cooler, a defrost water receiver for receiving defrost water from the cooler, a heating plate for evaporating the defrost water in the defrost water receiver, and a machine housing the rotary compressor. an evaporation-promoting blower installed in a room to cause forced convection in the machine room; a defrosting control device that starts defrosting when the operating time of the rotary compressor is accumulated for a predetermined time; A blower that circulates the air, a damper that adjusts the temperature within the refrigerator by opening and closing the amount of cold air circulated by the blower, and a timer that measures the cumulative time of continuous open time of the damper. a value of the cumulative continuous "open" time measured by the timer after the predetermined cumulative operating time of the rotary compressor;
An evaporation control device for a refrigerator configured to operate the evaporation-promoting blower in synchronization with the operation of the rotary compressor until the next defrosting when the value exceeds a preset value.