JPH109751A - Refrigerator with defrosting glass tube heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damages caused by a quick expansion of air in a glass tube when starting defrosting operation and corrosion degradation of a heater wire resultant from sucking up a water content during cooling operation in a defrosting glass tube heater which is used for defrosting a refrigerator. SOLUTION: A take-out section 7 of a lead wire of a defrosting glass tube heater 3 is sealed with a seal material 11 molded with a shape memory film while a heat insulating heater 12 is provided so as to insulate the seal material 11. It is, therefore, possible to prevent the glass tube from being damaged when starting defrosting operation or protect the heater wire from being corroded and degraded attributable to the water content absorbed during an initial period of cooling operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator provided with a glass tube heater for defrosting.

[0002]

2. Description of the Related Art A conventional refrigerator equipped with a glass tube heater for this type of defrosting is a well-known refrigerator, for example, a structure as shown in Japanese Utility Model Laid-Open No. 4-20989 is common. . This will be described below with reference to FIGS.

FIG. 5 shows a schematic mounting structure of a cooler and a glass tube heater for defrosting, and FIG. 6 is an enlarged cross-sectional view of a portion A (connection portion between a heater wire and a lead wire) in FIG. is there. FIG. 7 is an electric circuit diagram.

As shown in the drawings, 1 is a cooler, 2 is a compressor, 3 is a glass tube heater for defrosting, 4 is a glass tube,
5 is a heater wire, 6 is a cap, 7 is a lead wire lead-out portion, 8 is a lead wire, 9 is a defrost timer, and 10
Is a bimetal thermostat.

In such a configuration, the operation of the compressor 2 and the defrost glass tube heater 3 is controlled by a defrost timer 9 and a bimetal thermostat 10.
That is, when the cumulative operation time of the compressor 2 reaches a predetermined time, the timer contact is switched from 9-b to 9-a, the electricity is supplied to the glass tube heater 3 for defrosting, and the defrosting of the cooler 1 is started. When the defrosting is completed by the radiation heat of the glass tube heater 3 for defrosting, the bimetal thermostat 10 is turned off, the timer motor is rotated, the timer contact is switched again to 9-b, and the cooling operation is started again.

[0006]

However, in the above-mentioned conventional configuration, there is a risk of glass breakage due to expansion of air inside the glass tube at the initial stage of energization of the glass tube heater for defrosting, and the cooling operation after the energization is completed. As soon as it switches, the expanded air in the heater tube contracts,
The surrounding high humidity air may be inhaled to cause corrosion deterioration of the heater wire.

The present invention has been made to solve such a conventional problem, and the glass tube is damaged by the start of defrosting, that is, the rapid expansion of air inside the glass tube at the beginning of energization of the heater.
Another object of the present invention is to provide a refrigerator provided with a means for preventing the occurrence of corrosion deterioration of a glass tube heater for defrosting due to inhalation of high-humidity air or moisture into a heater tube at the end of energization.

[0008]

In order to solve the above-mentioned problems, the present invention applies a sealing material formed of a shape memory film to a lead wire lead-out portion of a glass tube heater for defrosting.

In addition, a heater for keeping the seal material made of the shape memory film and a control circuit for the heater for keeping the heat are provided. Due to such a sealing structure at the junction between the heater wire and the lead wire, the glass tube is damaged due to a rapid expansion of the air in the glass tube at the beginning of defrosting, or the moisture inside the glass tube heater at the time of switching to the cooling operation. Prevents corrosion deterioration due to inhalation of water.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to solve the above-mentioned problems, the present invention according to claim 1 of the present invention provides a cooling device and a cylindrical glass tube disposed below the cooling device. A glass tube heater for defrosting composed of a heater wire and a cap, and a sealing material composed of a shape memory film is applied to a lead wire lead-out portion provided on a cap of the glass tube heater for defrosting.

The invention according to claim 2 is provided with the shape memory film, a heater for keeping the shape memory film warm, and a control circuit for the heater for keeping heat.

As described above, since the seal member made of the shape memory film is used for the lead wire lead-out portion provided on the cap of the glass tube heater, it is possible to prevent moisture from being sucked into the glass tube heater when switching to the cooling operation. It is possible to prevent corrosion deterioration of the heater wire.

Further, by switching to defrosting and stopping the compressor and energizing the heat retaining heater for a certain period of time, the air inside the glass tube does not expand rapidly, so that the glass tube can be prevented from being damaged.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. Note that the same components as those of the conventional example are denoted by the same reference numerals and description thereof is omitted.

(Embodiment 1) In FIG. 2, reference numeral 11 denotes a sealing material formed of a shape memory film. At a low temperature, a knitted fabric shrinks and becomes dense to allow air molecules to permeate. Cut off. Conversely, at high temperatures, the knitted structure expands and becomes coarse, allowing water molecules to permeate.

By sealing the lead wire lead-out portion 7 of the glass tube heater 3 for defrosting with the sealing material 11 formed of such a shape memory film, the lead wire draw-out portion 7 is shut off during the cooling operation, and the lead wire draw-out is performed. The inhalation of water molecules from the section 7 is prevented, and the air inside the glass tube heater 3 for defrost cools and contracts. In addition, when the glass tube heater 3 for defrosting is energized, the knitted structure of the sealing material 11 of the shape memory film becomes coarse, and water molecules are released to the outside of the glass tube together with the expanded air inside the glass tube.

Therefore, the inhalation of water molecules due to the expansion and contraction of the air inside the glass tube heater for defrosting is blocked, thereby preventing the heater wire from being corroded and deteriorated.

(Embodiment 2) In FIG. 3, reference numeral 12 denotes a heater for keeping the temperature of the sealing material 11 formed of a shape memory film. In FIG. 4, reference numeral 13 denotes a control circuit for controlling the compressor 2, the glass tube heater 3 for defrosting and the heater 12 for keeping the shape memory film warm, and integrates the operation time of the compressor 2. During the cooling operation, the knitted structure of the shape memory film is dense and shuts off the inhalation of water molecules into the glass tube heater 3 for defrosting. When the accumulated time of the compressor 2 reaches the set value, the compressor 2
Is turned off, and at the same time, electricity is supplied to the shape memory film keeping heater 12 for a certain period of time. By such control, the heater 12 for keeping the shape memory film warm is turned off and the glass tube heater 3 for defrosting is turned on after the knitting structure of the sealing material 11 by the shape memory film changes from dense to coarse.

Therefore, the knitting structure of the shape memory film is roughened immediately before the start of defrosting, so that breakage of the glass tube due to rapid expansion of the air inside the glass tube after the start of defrosting can be prevented.

[0020]

As is apparent from the above description, claim 1
According to the invention described above, since the sealing material formed of the shape memory film is provided in the lead wire lead-out portion, during cooling operation, water molecules are prevented from being sucked into the glass tube heater for defrosting, and the heater wire is prevented. This prevents corrosion deterioration of the steel.

According to the second aspect of the present invention, the sealing material formed by the shape memory film is provided with a heater for keeping heat, and the heater is energized at the same time as the compressor is turned off, and is turned off after a certain period of time. The glass tube can be prevented from being damaged due to rapid expansion of the air inside the glass tube.

[Brief description of the drawings]

FIG. 1 is a front view of a mounting structure of a cooler and a defrost glass tube heater according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a portion A in FIG. 1;

FIG. 3 is an enlarged sectional view of a main part of a glass tube heater for defrosting in Embodiment 2 of the present invention.

FIG. 4 is a block diagram of the same control circuit.

FIG. 5 is a front view of a mounting structure of a conventional cooler and a glass tube heater for defrosting.

FIG. 6 is an enlarged sectional view of a main part of the same.

FIG. 7 is an electric circuit diagram of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooler 3 Glass tube heater for defrost 4 Glass tube 5 Heater wire 6 Cap 7 Lead wire lead-out part 11 Seal material 12 Heating heater 13 Control circuit part

Claims (2)

[Claims] 1. A defrosting glass tube heater having a cooler, a heater wire and a cap wound in a coil shape in a cylindrical glass tube disposed below the cooler, and a defrosting glass tube heater. A refrigerator with a glass tube heater for defrosting, wherein a sealing material formed of a shape memory film is applied to a lead wire lead-out portion provided on a cap. 2. The refrigerator with a glass tube heater for defrost according to claim 1, further comprising a shape memory film, a heater for keeping the shape memory film warm, and a control circuit for the heater for keeping heat.