JPS61153469A - Refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a refrigerator having a freezer compartment, a refrigerator compartment, and a third compartment whose temperature is independently controlled in most of the refrigerator compartment.

Conventional technology A conventional example will be explained with reference to FIGS. 5 to 7.

Reference numeral 1 denotes a refrigerator body, which is composed of an outer box 2, an inner box 3, and a foamed heat insulating material 4 filled between these two boxes.

5 is a top plate 6a, a bottom plate 6b, and a heat insulating material 6 inserted between both plates.
A partition wall constructed of C defines a freezing chamber 6 in the upper part of the main body 1 and a refrigerating chamber 7 in the lower part, and a cooler 8 for a refrigeration cycle and a blower 9 for forced ventilation are housed inside. 1o
is a third chamber (hereinafter referred to as the low temperature chamber 10) provided in a large part of the refrigerating chamber 4, with the bottom plate 6b of the partition wall 6 serving as a top plate, and a heat insulating plate 1.
0a, it is partitioned into a substantially airtight state by a heat insulating door 10b, and the temperature range (for example - 3 to o'C).

Reference numeral 11 denotes a temperature control device, which houses a damper thermostat 12 for adjusting the amount of cold air to the refrigerator compartment 7, a damper thermostat 13 for adjusting the amount of cold air to the cold room 10, and a discharge passage 14 to the refrigerator compartment 7, a cold room. Discharge passage 15 to 10
is formed.

16, 17, and 18 are respectively connected from the discharge side of the blower 9 to the freezer compartment 6.
, the cold room 7, and the cold room 1o, and the cold room ventilation duct 17 and the cold room ventilation duct 18 are separated by a partition plate 19. 20°, 21.22 are suction passages for the freezer compartment, refrigerator compartment, and cold room, respectively.

Further, 23 is a defrosting heater provided in the cooler 8, 24 is a bimetal thermostat for detecting the end of defrosting, and 26 is a drain pipe for draining the defrosting water defrosted by the defrosting heater 23. A heater 26 provided in the heat insulating material 6c of the partition wall 5 is a heat-retaining heater that is provided close to the bottom plate 6b of the partition wall 5 and keeps the area around the drain pipe 25 warm.

27 is a compressor of the refrigeration cycle, and 28 is a thermostat that controls the operation of the compressor 27.

Next, the electric circuit will be explained.

A defrosting timer device 29 is composed of a timer motor 30 and a switching contact 31, and one end of a parallel circuit of the compressor 27 and the blower 9 is connected to the a contact of the switching contact 31. The b contact of the switching contact 31 is connected to one end of a parallel circuit of a defrosting heater 23 and a heat-retaining heater 26 around the drain pipe via a bimetal thermostat 24 that detects the end of defrosting. That is, the compressor 27 and the blower 9
One end of the parallel circuit is connected to the power supply via the switching contact 31 and the thermostat 28, and the other end is directly connected to the power supply, and one end of the parallel circuit of the defrosting heater 23 and the heat retention heater 26 is connected to the bimetal thermostat. 24, switching contact 31
The B contact is connected to the power supply via the thermostat 28, and the other end is directly connected to the power supply. Further, one end of the defrosting timer motor 30 is connected to a power source via a thermostat 28, and the other end is connected to a power source via a parallel circuit of the defrosting heater 23 and the heat-retaining heater 26.

Problems to be Solved by the Invention Conventionally, in such a configuration, air cooled by the cooler 8 is supplied into the freezer compartment 6 through the freezer compartment ventilation duct 16 by the blower 9, cools the freezer compartment 6, and then is sent to the freezer compartment suction. It is returned to the cooler 8 through the passage 20. At the same time, the cold air passing through the refrigerator compartment ventilation duct 17 is controlled to an appropriate amount by the damper thermostat 12, and is supplied to the refrigerator compartment 7 via the discharge passage 14 to cool the refrigerator compartment 7. It is returned to the cooler 8 via the filter. Further, the cold air passing through the cold room ventilation duct 18 is adjusted to an appropriate amount by the damper thermostat 13, and is supplied into the cold room 1o through the discharge passage 16 and cooled to a desired low temperature, after which it is passed through the cold room suction passage 22. is returned to the cooler 8 via. Next, the cooling action continues by the operation of the compressor 27 in this manner, and when the defrosting timer motor 3o integrates the operation for a predetermined time, the contact of the switching contact 31 is switched from the a contact to the b contact, and the compressor 27 and the blower 9 is stopped, the defrosting heater 23 is energized to defrost the cooler 8, and the heat retaining heater 26 is also energized to warm the area around the drain pipe 25 and drain the defrosting water smoothly. let During this time, the timer motor 30 is short-circuited by the bimetal thermostat 24 and stops. After that, when the defrosting of the cooler 8 progresses and the temperature rises, and the bimetal thermostat 24 detects the end of defrosting and opens the contact, the timer motor 3o is energized again (normally, the resistance of the timer motor 3o is Defrosting heater 2
Since the parallel resistance of 3 and the heat-retaining heater 26 is extremely large, most of the partial pressure is applied to the timer motor. ) The switching contact 31 returns from the B contact to the A contact, and the compressor 27,
The blower 9 restarts its operation and performs the cooling operation again.

However, in this configuration and operation, when the outside air temperature drops considerably, the temperature of the cooler 8 also drops considerably, and the cold room 1o installed directly below is heated through the insulation material 6C of the partition wall 6 and the bottom plate 6b. There was a problem in that the room was overcooled and the stored fresh food was frozen and damaged, regardless of the temperature control function of the damper thermostat 13 for the low-temperature room. Also, at the same time, the drain pipe 26
Since the area around 0 is also considerably cooled, if the heat-retaining heater is energized only during defrosting, the temperature cannot be raised sufficiently, and the draining action of the drain pipe 26 cannot be performed smoothly.
There was also a risk that ice would form around the drain pipe 26, and that the drain pipe 26 would eventually become closed due to freezing, making it impossible to drain water.

In view of the above points, it is an object of the present invention to simultaneously prevent overcooling of the third chamber and freezing of the area around the drain pipe under low outside temperatures.

Means for Solving the Problems In view of the above-mentioned problems, the present invention provides a heat-retaining heater provided around the drain pipe at least close to the bottom plate of the partition wall, which is energized only during defrosting at normal outside temperature. A switching mechanism is provided to turn on electricity even when the temperature is low, other than during defrosting.

Accordingly, according to the present invention, with the above-mentioned configuration, when the outside temperature is low, the energization rate of the heat-retaining heater is increased to prevent overcooling of the third chamber and to prevent freezing of the area around the drain pipe at the same time.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3. In addition, the same reference numerals are given to the same configuration as the conventional one, detailed explanation thereof will be omitted, and only different parts will be described. 3
2 is an outside air temperature thermostat installed in a part of the outer shell of the main body 1, which closes the contact to the C contact side when the outside air temperature exceeds a predetermined temperature;
It is configured to switch to the d contact side when the outside air temperature falls below a predetermined temperature. Here, the C contact is electrically connected from an intermediate point between the defrosting heater 23 and the bimetal thermostat 24, and the D contact is electrically connected to one end of the power source. Further, one end of the heat-retaining heater 26 around the drain pipe is connected to one end of a constant power source, and the other end is connected to a common contact point of the outside temperature thermostat 32.

In this configuration, if the outside temperature is above a predetermined value, the outside temperature thermostat 32 switches! It is connected to the DC contact side, and the heat retention heater 26 forms a parallel circuit with the defrosting heater 23, and is energized only during defrosting. On the other hand, if the outside air temperature falls below a predetermined value, the switching contact of the outside temperature thermostat 32 is connected to the d contact side, and the heat retention heater 26 is connected to the d contact side.
is directly connected to a power source and is constantly energized, thereby sufficiently warming the cold room 10 to prevent overcooling, and also sufficiently warming the area around the drain pipe 25 to prevent freezing.

FIG. 4 shows another embodiment of the present invention, in which the d contact of the outside temperature thermostat 32 is connected to the power supply via the contact of the thermostat 28. That is, when the outside temperature falls below a predetermined value, the heat-retaining heater 26 is connected to the power source via the thermostat 28, and is energized in synchronization with the closing of the thermostat, which also sufficiently heats the cold room 1o. This prevents overcooling, and also sufficiently warms the area around the drain pipe 260 to prevent freezing. Which of the above examples should be used may be selected depending on the required heating amount.

Effects of the Invention As is clear from the above explanation, the present invention provides a freezer compartment and a refrigerator compartment each of which is partitioned by a partition wall, and a third compartment which is partitioned into the refrigerator compartment using the bottom plate of the partition wall as a top plate. , a cooler housed in the partition wall, a drain pipe for draining defrosting water from the cooler, and a heat-retaining heater provided at least close to the bottom plate of the partition wall to keep the area around the drain pipe warm. and an outside temperature thermostat that switches contacts depending on the outside temperature, and the heat-retaining heater is energized only during defrosting when the outside temperature thermostat detects a predetermined temperature or higher, and during defrosting when the outside temperature thermostat detects a predetermined temperature or lower. Since the structure is configured to supply electricity to other parts as well, it does not unnecessarily increase the power consumption of the heat retention heater at normal outside temperatures, and automatically increases the amount of heat that the heat retention heater consumes when needed at low outside temperatures. By increasing the energization rate to provide sufficient heating, it is possible to prevent overcooling of the third chamber and to safely preserve food, as well as to prevent functional failure due to freezing of the drain pipe. Its implementation and practical effects are extremely high.

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram of a refrigerator showing an embodiment of the present invention;
Fig. 2 is an overall sectional view of the refrigerator, Fig. 3 is a partial sectional view thereof, Fig. 4 is a control circuit diagram of a refrigerator showing another embodiment of the present invention, and Fig. 5 is an overall sectional view of the refrigerator showing a conventional example. 6 is a partial sectional view thereof, and FIG. 7 is an electric circuit diagram thereof. 6... Division wall, 6b... Division wall bottom plate,
8...Cooler, 10...Third chamber, 2
6...Drain pipe, 26...Heater for heat retention, 32...Outside temperature thermostat Name of agent Patent attorney Satoshi Nakao and one other person Figure 1

Claims (1)

[Claims] A freezer compartment and a refrigerator compartment defined by a compartment wall, a third compartment defined in the refrigerator compartment using the bottom plate of the compartment wall as a top plate, a cooler housed in the compartment wall, and the cooler a drain pipe for discharging defrosting water; a heat-retaining heater provided at least close to the bottom plate of the partition wall to keep the area around the drain pipe warm; and an outside temperature thermostat that switches a contact point depending on the outside temperature; The heat retention heater is configured to be energized only during defrosting when the outside temperature thermostat detects a predetermined temperature or higher, and to be energized even during defrosting when the outside temperature thermostat detects a predetermined temperature or lower.