JPH0221747Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a cooling storage such as a storage or freezer that uses a radiant heater as a defrosting heater, and relates to a structure for mounting a protection device for preventing overheating.

Configuration of the conventional example and its problems The conventional example will be explained with reference to FIG. This is a longitudinal sectional view of the storage. 1 is a cabinet body, 2 is a door, 3 is a gasket for sealing between the cabinet body 1 and the door 2, and a cooler 5 is arranged in a cooling chamber 4 inside. 6″
A pipe heater for defrosting is provided by making a groove in the end plate of the cooler 5, and crimping the heater into the groove to uniformly heat the cooler. 7 is a cooler cover, 8 is a cold air circulation blower for circulating the cold air from the cooler 5 into the cooling chamber, and 9 and 10 are bimetallic parts installed on the top of the cooler 5 to detect the end of defrosting and to prevent overheating. A temperature fuse as a protective device. A drain guide 11 and the like are arranged at the lower part of the cooler 5 to receive defrosting water and discharge it to the outside of the refrigerator. Note that 12 is a compressor.

As a defrosting method for the cooler 5 of the refrigerator with such a configuration, the operation time of the compressor 12 is accumulated using a timer (not shown), and when the predetermined operation time is reached, the operation is automatically switched from the cooling side to the defrosting side. The electric circuit switches to
The defrosting pipe heater 6'' arranged to uniformly heat the cooler 5 is energized. When the cooler 5 rises to a predetermined temperature, the bimetal 9 for detecting the end of defrosting operates and the defrosting ends. Then, the electric circuit is automatically switched from the defrosting side to the cooling side.Also, a temperature fuse 10 having an operating temperature sufficiently higher than the operating temperature of the bimetal 9 is installed near the defrosting detection bimetal 9.
is installed. This prevents abnormal overheating of the heater 6'' due to a failure of the bimetal 9, and prevents smoke and ignition of refrigerator components.However, recently, the radiant heater 6 has been replaced as a heater to replace the pipe heater 6''. ' has come to be used because it requires less man-hours to assemble the heater itself and is inexpensive. This type of heater has a cooler 5 like a pipe heater 6''.
It is not possible to arrange the device so that the temperature rise in each part is uniform, and the installation location is limited to the lower part of the cooler 5. Therefore, the heating to the cooler 5 is higher near the radiant heater 6'. However, there is a drawback that localized heating becomes uneven as the distance increases.
This drawback also affects the installation location of the overheat protection device.

That is, if the radiant heater 6' is used and the bimetal 9 and the temperature fuse 10 are installed on the top of the cooler 5 as in the conventional case, if the bimetal 9 should fail, by the time the temperature fuse 10 operates, The components near the radiant heater 6' are:
It had the disadvantage of causing smoke and ignition due to local heating. To prevent this, the radiant heater 6'
If the temperature fuse 10 is installed nearby, the temperature fuse 10 will operate faster than the bimetal 9, which is installed at the part where the temperature rises the slowest, in order to completely defrost the air due to the strong influence of local heating. As a result, defrosting ends before the frost adhering to the cooler 5 is completely melted, causing deterioration of cooling performance. It is possible to raise the operating temperature of the temperature fuse 10 even higher to prevent it from operating faster than the bimetallic fuse 9, but as a component of the refrigerator,
When plastic materials such as ABS and styrene are used, there is a natural limit to the upper limit of the operating temperature that will thermally protect these components, and it is difficult to raise them higher than before.

Also, since this type of temperature fuse is used as a safety device, it is common to have to replace the parts once it operates, which causes various damage such as the need to replace parts every time it malfunctions. .

Purpose of the invention This invention proposes that when a radiant heater is used as a defrosting heater, even if a temperature fuse or other overheat prevention protection device is installed near the radiant heater, the temperature will be lower than that of a bimetal for defrosting termination during normal defrosting. The overheating protection device operates first to prevent deterioration of cooling performance due to residual frost, and to operate immediately in the event of an abnormality such as the heater not turning off and continuing to operate even though the frost has disappeared. An object of the present invention is to provide a highly reliable cooling storage that can protect cooling storage components from abnormal heating.

Composition of the invention The invention consists of a defrosting heater installed below the cooler, a bimetal for detecting the end of defrosting installed at a position away from the radiant heater of the cooler, and a drain guide located below the radiant heater. , a mounting piece formed by bending the side wall of the drain guide along the back surface, and a protection device for preventing overheating such as a temperature fuse, which is held by the drain guide and the mounting piece and is connected in series with the radiant heater together with a bimetal. The operating temperature of the overheat prevention protection device is set to a higher temperature than the operating temperature of the bimetal for detecting the end of defrosting.

DESCRIPTION OF EMBODIMENTS The structure of an embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

1' is inside the cooling chamber, 2' is a cooler, 3' is a cold air circulation blower for circulating the cold air of the cooler 2' into the cooling room 1, and 4' is a fan ring part of the cold air circulation blower 3'. The cover also serves as a cooler cover, and a defrosting radiant heater 5' is disposed below the cooler 2'. A drain guide 6 receives defrosting water from the cooler 2', and is installed below the defrosting radiant heater 5'. A drain hole (not shown) is provided at the bottom of the drain guide 6, and water is drained from the drain hole to the outside of the refrigerator via a drain pipe (not shown) in the cabinet body using a well-known structure. 7' is a bimetal for detecting the end of defrosting, which is provided on the upper part of the cooler 2'. 8' is a slit 6d formed in a part of the side wall 6c on the back side of the drain passage 6b of the drain guide 6, bent along the back side to form a mounting piece 6e, and a superheated pipe sandwiched between the mounting piece 6e and the back side. This is a protective device 8' (hereinafter referred to as temperature fuse 8'). The operating temperature of the temperature fuse 8' is set to be sufficiently higher than that of the bimetal 7'.

The operation of this configuration will be explained. The operating time of the compressor 12 is accumulated using a timer, etc., and when the predetermined operating time is reached, the cooling circuit is switched to the defrosting circuit, the radiant heater 5' is energized, and the frost that has adhered to the cooler 2' begins to melt. .
The temperature fuse 8' is attached to the back surface of the drain guide 6, making it susceptible to the radiant heat of the radiant heater 5'. However, when the frost in the cooler 2' begins to melt, the drain passage 6b becomes wet with low-temperature defrosting water, and even though the temperature near the temperature fuse 8' during defrosting is near the radiant heater 5', This prevents malfunctions such as turning off the bimetal 7' prior to activation during defrosting. When the frost in the cooler 2' completely melts, the temperature of various parts near the cooler 2' will rise rapidly, but due to the difference in the operating temperature settings of the temperature fuse 8' and the bimetal 7', is operated first and returns to cooling operation.

Effects of the invention As described above, the present invention has an overheating protection device attached to the back of the drain guide that discharges the defrosting water from the cooler to the outside of the storage space of the refrigerator, etc., so as to sense the temperature of the defrosting water during defrosting. Because of this, even though the temperature is easily detected near the radiant heater, it is possible to prevent malfunctions caused by bimetal activation during normal defrosting and to deal with localized heating. Even in such a case, the temperature of the storage components can be sufficiently protected in the event of abnormal heating.

[Brief explanation of the drawing]

Figure 1 is a vertical sectional view of a conventional refrigerator;
The figure is a longitudinal sectional view of a refrigerator showing an embodiment of the present invention.
FIG. 3 is a perspective view of the drain guide. 2'...Cooler, 5'...Radiant heater, 6
...Drain guide, 6e...Mounting piece, 8'...Protective device for overheating prevention (temperature fuse).

Claims (1)

[Scope of utility model registration request] a cooler provided in the storage main body; a radiant heater for defrosting provided below the cooler; a bimetal for detecting the end of defrosting provided at a position away from the radiant heater of the cooler; A drain guide located below the radiant heater, a mounting piece formed by bending the side wall of the drain guide along the back surface, and held by the drain guide and the mounting piece, together with the bimetal for detecting the end of defrosting. The electric circuit of the storage is provided with an overheat prevention protection device such as a temperature fuse connected in series with the radiant heater, and the operating temperature of the overheat prevention protection device is higher than the operating temperature of the bimetal for detecting the end of defrosting. Cooling storage set to .