JP2002364973A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator which can surely execute draining even when the surface temperature of a heater for defrosting is suppressed to the spontaneous ignition temperature of a refrigerant or below in order to use a combustible refrigerant. SOLUTION: The refrigerator is equipped with a cooler provided inside the main body of the refrigerator, the heater for defrosting provided below the cooler and a drainpipe for draining drain water melting from a cooler due to the heat of the heater for defrosting, outside the main body of the refrigerator, and uses the combustible refrigerant as the refrigerant. Herein a means for conducting the heat of the heater to an inflow port of the drainpipe is provided and the surface temperature of the heater is made to be the spontaneous ignition temperature or below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator using a flammable refrigerant, and in particular, ensures drainage even when the surface temperature of a heater for defrosting is kept below the spontaneous ignition temperature of the flammable refrigerant. It relates to a refrigerator that can be used.

[0002]

2. Description of the Related Art FIG. 4 is a front view and a side view of a main part around a cooler of a conventional refrigerator. In the figure, 1 is a refrigerator main body, 2 is a cooler, 3 is a fan for sending air cooled by the cooler 2 to each storage room, 4 is a heater roof, and 5 is a drain water melted by a heater 7 for defrosting. A drip tray 6 is a drain pipe for discharging drain water out of the refrigerator.

A glass tube heater is used as the defrosting heater 7 disposed below the cooler 2, and a heater wire 10 (heating element) is housed in a glass tube 9 and an insulated cord wire 11 is provided. And heat is generated. The heater wire 10
Both ends are insulated and waterproof by the cap 8 and the cord wire 11.

When the defrost heater 7 is energized, the frost adhering to the upper cooler 2 is melted by radiation and natural convection, and the radiation causes the drip tray located below the defrost heater 7 to radiate. Frost accumulated near the inlet of the drain pipe 5 and the drain pipe 6 is melted, and drain water is discharged from the drain pipe 6 to the outside of the refrigerator.

[0005]

At present, HFC-134a, which is widely used as a refrigerant for refrigerators, has no ozone depleting ability, but has a global warming potential GWP of 1300.
Therefore, the use of hydrocarbon-based refrigerants such as isobutane and propane, which have no ozone depleting ability and low global warming potential, is being studied. However, since these hydrocarbon-based refrigerants are flammable, it is important to prevent ignition from electrical components if the refrigerant leaks from the refrigeration cycle.

At present, the surface temperature of a glass tube heater widely used as a defrosting heater of a refrigerator may exceed the spontaneous ignition temperature of a hydrocarbon-based refrigerant. There is a problem not to be. In addition, since the heater wire temperature is higher than the glass tube surface temperature, if the cap and the glass tube are not completely sealed, the leaked refrigerant may enter the glass tube and be ignited by the heater wire.

Various measures have been proposed to solve this problem. FIG. 5 is a cross-sectional view showing a heater for defrosting in which a cap and a glass tube are sealed, for example, disclosed in JP-A-2000-283635. In the figure, 12 is a sheath tube, 13 is an insulating material, and 14 is a fin. Sheath tube 12
The heater wire 10 filled with the insulating material 13 is accommodated therein,
Both ends are insulated and sealed by a cap 8, and electricity is supplied from the outside via a cord wire 11 to perform heating. Sheath tube 1
Fins 14 are provided on the outer periphery of the two to promote heat transfer with the surrounding air.

When power is supplied to the defrost heater 7, the temperatures of the sheath tube 12 and the fins 14 increase, and the frost adhering to the cooler 2 is melted by radiation and natural convection.
Fins 14 are provided on the defrost heater 7 to increase the surface area, so that natural convection is promoted, and even when the surface temperature of the defrost heater 7 is lowered, the amount of heat required for defrost is supplied to the cooler 2. Can communicate. Therefore, by setting the surface temperature of the defrosting heater 7 to be equal to or lower than the spontaneous ignition temperature of the combustible refrigerant,
Even if the flammable refrigerant leaks, there is no danger of ignition on the surface of the heater 7 for defrosting.

Further, since the heater wire 10 is filled and sealed with the insulating material 13, there is no danger that the flammable refrigerant directly contacts the heater wire 10 and ignites even if the flammable refrigerant leaks.

However, in the configuration of the conventional example shown in FIG. 5, since the surface temperature of the defrost heater 7 is suppressed, the radiant heat from the defrost heater 7 is reduced, so that the defrost heater 7 is less than the defrost heater 7. The frost deposited near the inlet of the drip tray 5 and the drain pipe 6 located below cannot be completely melted, and a problem that drain water cannot be discharged may occur.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In order to use a flammable refrigerant, even if the surface temperature of the heater for defrosting is suppressed below the spontaneous ignition temperature of the refrigerant, An object of the present invention is to provide a refrigerator capable of reliably discharging drain.

[0012]

SUMMARY OF THE INVENTION A refrigerator according to the present invention includes a cooler provided inside a refrigerator body, a defrost heater provided below the cooler, and heat generated by the defrost heater. A drain pipe for discharging drain water melted from the cooler to the outside of the refrigerator main body; and a refrigerator using a combustible refrigerant as a refrigerant, wherein a means for transmitting heat of a defrost heater to an inlet of the drain pipe is provided. The surface temperature of the frost heater is set to be lower than the spontaneous ignition temperature of the refrigerant.

Further, a cooler provided inside the refrigerator body, a defrost heater provided below the cooler, and drain water melted from the cooler by heat of the defrost heater is supplied to the outside of the refrigerator body. In a refrigerator using a combustible refrigerant as a refrigerant, a member receiving heat of a defrost heater is provided, and a means for transmitting the heat received by the member to an inlet of the drain pipe is provided, The surface temperature of the defrosting heater is set to be lower than the spontaneous ignition temperature of the refrigerant.

Further, the heater for defrosting and the inlet of the drain pipe are connected by a heat conductive member having good heat conductivity.

Further, a heater roof is provided above the defrosting heater, and the heater roof and the inflow port of the drain pipe are connected by a heat conductive member having good heat conductivity.

Further, aluminum is used for the heat conducting member.

Further, the heat conducting member has an elongated shape.

Further, the heat conduction member is inserted to the inside of the inflow port of the drain pipe.

Further, the heat conducting member is formed in a plate shape.

Further, the apparatus has a drip tray for receiving the drain water melted from the cooler by the heat of the defrost heater, and the plate-like heat conducting member is connected to the drip tray while keeping the inlet of the drain pipe from being blocked. It is to make contact.

Further, the heat conduction member is fixed to the heater roof in advance.

Further, the heat conducting member is integrated with the heater roof.

Also, the heater roof is made of a material having good heat conductivity.

Further, a sheath tube heater is used as a heater for defrosting.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. FIG. 1 shows the first embodiment, and is a front view and a side view of a main part around a cooler of a refrigerator. Here, members having the same functions as those of the conventional example are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 1, for example, a sheath tube heater is used as the defrost heater 7. This is one in which the heater wire is completely sealed and the surface temperature is lower than the spontaneous ignition temperature of the combustible refrigerant used. As means for transferring the heat of the defrost heater to the inlet of the drain pipe, a heat conducting member 15 is provided so as to connect the heater for defrost 7 and the inlet of the drain pipe 6.

As a refrigerant for the refrigerator, a flammable hydrocarbon-based refrigerant such as R600a (isobutane) or R290 (propane) having a small global warming potential is used.

At the time of defrosting, the heater 7 for defrosting is energized to melt and remove frost that has reached the cooler 2 by radiation and natural convection. Here, the surface temperature of the defrost heater 7 is equal to or lower than the spontaneous ignition temperature of the refrigerant, but since the heat conducting member 15 provided to connect the defrost heater 7 and the drain pipe 6 is heated, the drain pipe is heated. The frost accumulated at the inlet of No. 6 is melted, and the drain water can be reliably discharged out of the refrigerator.

The heat conducting member 15 is made of a material having excellent heat conductivity and water resistance such as aluminum, for example. An elongated shape such as a wire is wound around the surface of the heater 7 for defrosting. Is installed as follows. As shown in FIG. 1, by making the tip end reach deeper than the inlet of the drain pipe 6, the drain frozen in the middle of the drain pipe 6 is melted, and the drain can be discharged more reliably.

According to the above-described embodiment, the surface temperature becomes equal to or lower than the spontaneous ignition temperature of the flammable refrigerant, and the heater wire is completely sealed. By providing the heat conducting member 15 for transmitting to the inflow port of the drain pipe 6, even if a flammable refrigerant leaks, the defrost heater 7 does not ignite and drain water is reliably discharged out of the refrigerator. it can.

Embodiment 2 FIG. FIG. 2 shows the second embodiment, and is a front view and a side view of a main part around a cooler of a refrigerator. Note that members having the same functions as in the first embodiment are given the same reference numerals, and descriptions thereof will be omitted. In FIG. 2, the heat conductive member 15 is made of a material having excellent heat conductivity and water resistance, as in the first embodiment, and a plate-shaped member is attached so as to wind around the surface of the heater 7 for defrosting. ing. By making the heat conducting member 15 in a plate shape, a larger range of frost can be melted.

Further, as shown in FIG.
While not blocking the inlet of the drain pipe 6
By contacting with the drip tray 5, the heat of the defrosting heater 7 is also transmitted to the drip tray 5, and the frost accumulated in a larger area can be melted.

According to the above embodiment, the heat conducting member 1
By making the plate 5 a frost in a larger range can be melted. Further, the heat conduction member 15 is brought into contact with the drip tray 5 so as not to block the inflow port of the drain pipe 6, so that the heat of the defrost heater 7 is transmitted to the drip tray 5, and the heat is accumulated in a larger area. Thawed frost can be thawed.

Embodiment 3 FIG. 3 is a view showing the third embodiment, and is a front view of a main part around a cooler of a refrigerator. In addition,
Members having the same functions as in the first and second embodiments are denoted by the same reference numerals, and description thereof is omitted. In FIG. 3, the defrost heater 7 is fixed by the heater roof 4. The heater roof 4 is made of a material having good heat conductivity, and is provided with a heat conducting member 15 that connects the heater roof 4 and the inflow port of the drain pipe 6.

At the time of defrosting, the heater roof 4 receives heat from the heater 7 for defrosting, and transmits the heat received at the inlet of the drain pipe 6 through the heat conducting member 15 to melt the accumulated frost. is there.

The heat conducting member 15 may have an elongated shape as in the first embodiment, or may have a plate shape as in the second embodiment. Further, the heat conducting member 15 may be integrated with the heater roof 4.

By fixing the heat conducting member 15 to the heater roof 4 in advance, or by integrating the heat conducting member 15 and the heater roof 4, there is no need to increase the time and effort required for mounting to the refrigerator.

According to the above-described embodiment, the heat conduction member 15 is fixed to the heater roof 4 in advance, or
By integrating the heat conductive member 15 and the heater roof 4, drain water can be reliably discharged without increasing the time and effort required for mounting to the refrigerator.

[0038]

The refrigerator according to the present invention is provided with means for transmitting the heat of the defrosting heater to the inlet of the drain pipe, and the surface temperature of the defrosting heater is set to be lower than the spontaneous ignition temperature of the refrigerant. Even if one flammable refrigerant leaks, the heater is not ignited by the heater, and the drain water can be reliably discharged out of the refrigerator.

A member for receiving the heat of the defrost heater is provided, and means for transmitting the heat received by the member to the inlet of the drain pipe is provided. Thus, even if the flammable refrigerant leaks, the heater is not ignited, and the drain water can be reliably discharged out of the refrigerator.

In addition, since the heater for defrosting and the inlet of the drain pipe are connected by a heat conductive member having good thermal conductivity, the heat conducting member is heated by the heat of the heater for defrost, and the inlet of the drain pipe is heated. The frost that has accumulated on the surface is melted, and the drain water can be reliably discharged out of the refrigerator.

Further, a heater roof is provided above the defrost heater, and the heater roof and the inlet of the drain pipe are connected by a heat conductive member having good heat conductivity, so that the heat received by the heater roof heats the heat conductive member. As a result, the frost accumulated at the inlet of the drain pipe is melted, and the drain water can be reliably discharged out of the refrigerator.

Further, by using aluminum for the heat conducting member, the heat conductivity is good, the frost accumulated at the inlet of the drain pipe is reliably melted, and the drain water can be surely discharged out of the refrigerator.

Further, by making the heat conducting member slender, the frost accumulated at the inlet of the drain pipe can be reliably melted, and the drain water can be reliably discharged out of the refrigerator.

Further, by inserting the heat conducting member all the way into the inlet of the drain pipe, the drain frozen in the middle of the drain pipe is melted, and the drain can be discharged more reliably.

Further, by forming the heat conducting member in a plate shape, a larger range of frost can be melted.

Further, the apparatus has a drip tray for receiving the drain water melted from the cooler by the heat of the defrosting heater, and the plate-like heat conductive member is connected to the drip tray while keeping the inlet of the drain pipe from being blocked. The contact makes it possible to transmit the heat of the heater for defrosting to the drip tray and to melt the frost accumulated in a larger area.

Further, since the heat conducting member is fixed to the heater roof in advance, the drain water can be reliably discharged without increasing the time and effort required for mounting to the refrigerator.

Further, since the heat conducting member is integrated with the heater roof, drain water can be reliably discharged without increasing the time and effort required for mounting to the refrigerator.

Further, since the heater roof is made of a material having good heat conductivity, the heat of the defrosting heater can be more reliably transmitted to the inlet of the drain pipe.

Further, since the sheath tube heater is used as the defrosting heater, the heater wire can be securely sealed.

[Brief description of the drawings]

FIG. 1 shows the first embodiment, and is a front view and a side view of a main part around a cooler of a refrigerator.

FIG. 2 shows a second embodiment, and is a front view and a side view of a main part around a cooler of a refrigerator.

FIG. 3 shows the third embodiment, and is a front view of a main part around a cooler of a refrigerator.

FIG. 4 is a front view and a side view of a conventional refrigerator.

FIG. 5 is a sectional view of a main part of a defrosting heater in another conventional refrigerator.

[Explanation of symbols]

1 refrigerator body, 2 cooler, 3 fan, 4 heater roof, 5 drip tray, 6 drain pipe, 7
Defrosting heater, 8 cap, 9 glass tube, 10 heater wire, 11 cord wire, 12 sheath tube, 13 insulating material, 14 fins, 15 heat conduction member.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Akira Nishizawa 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation F-term (reference) 3L046 AA04 BA01 BA08 CA05 DA05 LA35 3L048 AA01 CA04 CB03 CD02 CE00

Claims (13)

[Claims] A refrigerator provided inside the refrigerator body,
A defrosting heater provided below the cooler; and a drain pipe for discharging drain water melted from the cooler by the heat of the defrosting heater to the outside of the refrigerator main body. A refrigerator provided with means for transmitting heat of the defrost heater to an inlet of the drain pipe, and wherein a surface temperature of the heater for defrost is set to be equal to or lower than a spontaneous ignition temperature of the refrigerant. . 2. A refrigerator provided inside the refrigerator body,
A defrosting heater provided below the cooler; and a drain pipe for discharging drain water melted from the cooler by the heat of the defrosting heater to the outside of the refrigerator main body. In the refrigerator used, a member for receiving the heat of the defrost heater is provided, and means for transmitting the heat received by the member to the inlet of the drain pipe is provided, and the surface temperature of the defrost heater is set to A refrigerator characterized by having a temperature below the auto-ignition temperature. 3. The refrigerator according to claim 1, wherein the heater for defrosting and the inflow port of the drain pipe are connected by a heat conductive member having good heat conductivity. 4. The refrigerator according to claim 2, wherein a heater roof is provided above the defrosting heater, and the heater roof and an inlet of the drain pipe are connected by a heat conductive member having good heat conductivity. . 5. The refrigerator according to claim 3, wherein aluminum is used for the heat conducting member. 6. The refrigerator according to claim 3, wherein the heat conducting member has an elongated shape. 7. The refrigerator according to claim 6, wherein the heat conducting member is inserted to a depth of an inlet of the drain pipe. 8. The refrigerator according to claim 3, wherein the heat conducting member is formed in a plate shape. 9. A drip tray for receiving drain water melted from the cooler by heat of the heater for defrosting,
9. The refrigerator according to claim 8, wherein the plate-shaped heat conductive member is brought into contact with the drip tray while not blocking the inlet of the drain pipe. 10. The refrigerator according to claim 4, wherein the heat conducting member is fixed to the heater roof in advance. 11. The refrigerator according to claim 4, wherein said heat conducting member is integrated with said heater roof. 12. The refrigerator according to claim 2, wherein the heater roof is made of a material having good heat conductivity. 13. The refrigerator according to claim 1, wherein a sheath tube heater is used as the defrosting heater.