JP2010032182A - Defrosting heater and cooling storage device comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a defrosting heater capable of applying an inexpensive material in coating of a lead wire by lowering a coating temperature of the lead wire of the defrosting hater, and being integrated with a temperature fuse. <P>SOLUTION: This defrosting heater 1 melting frost attached to a cooler, comprising a heater wire 3 and the lead wire 4 disposed inside of a glass tube 4, and a heat absorbing component 6 is disposed between the heater wire 3 and the coating 4a of the lead wire 4, thus the temperature of the coating 4a of the lead wire 4 is lowered, and the inexpensive thermoplastic resin can be used for the coating 4a of the lead wire 4. Further the defrosting heater can be integrated with the temperature fuse 7 by connecting the lead wire 4 and the temperature fuse 7 disposed inside of an insulating tube 8, in the insulating tube 8, and welding the coating 4a of the lead wire 4 and the insulating tube 8 at a high frequency, thus the number of components and assembling man-hours can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a defrosting heater that melts frost that adheres to and accumulates on a cooler of a refrigeration cycle such as a refrigerator, and a cooling storage device that includes the defrosting heater.

  As what is related to the defrosting heater currently used for the conventional refrigerator, the thing which made the nichrome wire the coil shape and covered it with the glass tube is known (for example, refer patent document 1).

  Hereinafter, the conventional defrosting heater will be described with reference to the drawings.

  FIG. 5 is a longitudinal sectional view of a main part of a refrigerator equipped with a conventional defrosting heater.

  In FIG. 5, the refrigerator main body 31 has a freezer compartment 32, a refrigerator compartment 33, a freezer compartment door 34, a refrigerator compartment door 35, a partition wall 36 that separates the freezer compartment 32 from the refrigerator compartment 33, and a freezer that sucks in air in the freezer compartment 32. Cooling chamber partition for partitioning the evaporator 40 and the freezing chamber 32 from the chamber suction port 37, the refrigeration chamber suction port 38 for sucking the air in the refrigeration chamber 32, the discharge port 39 for discharging cool air, the evaporator 40, the fan 41 for circulating cold air. A wall 42 is provided.

  Further, below the evaporator 40, a defrost heater 43 in which a heater wire having a coiled nichrome wire is covered with a glass tube, and evaporation generated when defrost water is directly dropped onto the defrost heater 43 and brought into contact therewith. A roof 44 for preventing sound and a metal bottom plate 45 are provided, and the defrost water collected by the eaves 46 is drained through a drain outlet 47.

  The operation of the refrigerator and defrost heater configured as described above will be described.

  When the freezer compartment 32 and the refrigerator compartment 33 are cooled, the evaporator 40 is cooled by circulating the refrigerant through the evaporator 40, and the fan 41 is operated in the same manner, whereby the freezer compartment inlet 37, The temperature rising air in the freezer compartment 32 and the refrigerator compartment 33 is sent from the refrigerator compartment suction port 38 to the refrigerator compartment, and heat is exchanged by the evaporator 40. The air cooled by the evaporator 40 is sent from the discharge port 39 into the freezer compartment 32, and the cool air is sent from the freezer compartment 32 to the refrigerator compartment 33 through a communication port (not shown).

  Here, the air that exchanges heat with the evaporator 40 is high due to inflow of high-temperature outside air by opening and closing the freezer compartment door 34 and the refrigerator compartment door 35, or evaporation of moisture contained in the stored food in the freezer compartment 32 and the refrigerator compartment 33. Humid air.

  Therefore, in the evaporator 40, the moisture in the air to be heat-exchanged is frosted and deposited. When the amount of frost accumulated increases, heat transfer between the surface of the evaporator 40 and the air that exchanges heat is hindered. In addition, the frost becomes ventilation resistance, and the amount of air supplied to the freezer compartment 32 and the refrigerator compartment 33 increases. The heat passing rate is reduced and insufficient cooling occurs.

  Therefore, by supplying current to the nichrome wire of the defrost heater 43 before the cooling becomes insufficient, heat rays are radiated from the nichrome wire to the evaporator 40 and peripheral components. At this time, a part of the heat ray radiated to the bottom plate 45 is reflected from the shape of the bottom plate 45 to the heater wire, and the other is reflected toward the evaporator 40 and other peripheral components. As a result, the frost adhering to the vicinity of the evaporator 40, the eaves 46, and the drain 47 is melted into water.

  Further, a part of the defrosted water melted in this way falls directly to the fence 46, and the other falls to the fence 46 by avoiding the defrost heater 43 by the roof 44, and is drained to the outside from the drain outlet 47.

  This type of defrosting heater 43 has a temperature fuse connected in series as a safety device so that energization is interrupted when the ambient temperature rises above a predetermined temperature.

  FIG. 6 shows the configuration of the defrost heater 43. The defrost heater 43 includes a connection terminal 49 and an insulating component 50 of the connection terminal 49 at the tip of the lead wire 48 in order to connect the lead wire 48 and a thermal fuse assembly (not shown) in series.

  FIG. 7 shows the configuration of the thermal fuse assembly. The thermal fuse assembly 51 has a thermal fuse 53 disposed inside an insulating tube 52, and includes a connection terminal 55 and an insulation component 56 of the connection terminal 55 at the tip of a lead wire 54. The insulating tube 52 and the lead wire 54 are in close contact with each other by a welded portion 52a of the insulating tube 52 welded by high frequency welding, thereby sealing the inside of the insulating tube 52 from the outside air.

And when connecting the defrost heater 43 and the thermal fuse assembly 51 in series, the connection terminal 49 of the defrost heater 43 is combined with the connection terminal 55 of the thermal fuse assembly 51.
JP-A-8-54172

  However, in the above conventional configuration, the lead wire 48 of the defrost heater 43 and the lead wire 54 of the thermal fuse assembly 51 are individually provided, and there is a problem that the configuration has a large number of parts.

  This is because the coating of the lead wire 48 of the defrosting heater 43 and the lead wire 54 of the thermal fuse assembly 51 needs to select different materials.

  That is, the lead wire 48 of the defrosting heater 43 is wired in the vicinity of the heater wire, and is affected by high temperature as the heater wire is energized during the defrosting operation of the refrigerator. Therefore, there was a need to select a relatively expensive material having high heat resistance.

  On the other hand, since the covering of the lead wire 54 of the thermal fuse assembly 51 needs to be installed inside the insulating tube 52 in a state where it is sealed from the outside air by high-frequency welding or the like with the insulating tube 52, the insulating tube 52 Therefore, it was necessary to select a thermoplastic resin such as vinyl chloride, which can be easily welded with the high frequency 52.

  Further, a material having high heat resistance such as silicone rubber that is used as a coating for the lead wire 48 of the defrost heater 43 is a material that is difficult to be welded to the insulating tube 52 by high frequency. It was difficult to seal the outside air.

  Furthermore, since the place where the connection terminal 49 of the defrost heater 43 and the connection terminal 55 of the thermal fuse assembly 51 are connected (connected) is in the vicinity of the evaporator 40, it adheres to the surface of the evaporator 40 during the defrosting operation. Corrosive substances such as chlorine and acetic acid contained in foods that have been suspended will float, resulting in environmental conditions that are likely to corrode. Therefore, in order to secure the corrosion resistance, the connected connection terminals 49 and 55 have to be stored in a bag made of polyethylene or the like and subjected to a corrosion resistance treatment such as sealing with a binding band or the like.

  The present invention solves the above-described conventional problems, and by incorporating a thermal fuse into the lead wire of the defrost heater, the number of parts and assembly man-hours are reduced, and a configuration with strong corrosion resistance is provided. It is the purpose.

  In order to solve the above conventional problems, a defrosting heater according to the present invention includes a glass tube, a heater wire installed inside the glass tube, a lead wire connected to the heater wire, and openings at both ends of the glass tube. A defrosting heater provided with a lead wire insertion hole for inserting the lead wire in the cap, wherein a heat absorbing component is provided between the heater wire and the covering of the lead wire. Is.

  Therefore, since the heat of the heater wire transmitted to the lead wire can be reduced by the heat absorbing component, the lead wire coating material can be made of an inexpensive material such as a thermoplastic resin.

  In the case of a refrigerator equipped with the above defrost heater, the temperature of the lead wire coating can be lowered below the upper limit of the use temperature of the thermoplastic resin even during the defrosting operation, and as a result, maintenance of safety can be maintained. And a cost-saving configuration can be expected.

  In addition, the defrosting heater of the present invention can be connected to a thermal fuse provided inside an insulating tube made of the same material by using an inexpensive material such as a thermoplastic resin for the lead wire coating material. As a result, the covering of the lead wire and the insulating tube are welded at high frequency, and the defrosting heater and the thermal fuse can be integrated.

  As a result, a defrosting heater integrated with the thermal fuse is obtained. As a result, a complicated connection configuration with a thermal fuse assembly including a large number of parts is not required, and the number of parts can be reduced. The man-hours required to connect the connection terminals to the lead wires by the caulking process, the man-hours to install the insulation parts to the connection terminals, and the man-hours to connect the connection terminals of the defrost heater and the connection terminals of the thermal fuse, which were necessary for connecting the thermal fuse The configuration can be reduced.

  The defrosting heater of the present invention can reduce the lead wire coating material by making the lead wire coating material inexpensive, such as a thermoplastic resin, and is integrated with a thermal fuse to reduce the number of parts and assembly. It can be set as the structure which reduced the man-hour.

  Moreover, the cooling storage device equipped with such a defrosting heater can configure the defrosting function at a low cost, and can further ensure the corrosion resistance at the connecting portion with the thermal fuse and increase the reliability. .

  Invention of Claim 1 is equipped with the glass tube, the heater wire installed in the inside of the glass tube, the lead wire connected to the heater wire, and the stopper which covers the both ends opening of the glass tube, A defrosting heater in which a lead wire insertion hole for inserting the lead wire is provided in a stopper, and a heat absorbing component is provided between the heater wire and the covering of the lead wire.

  With this configuration, the temperature of the heat transferred from the heater wire is lowered by the heat absorbing component. As a result, the temperature transmitted to the coating of the lead wire can be lowered, and the coating material of the lead wire can be made of an inexpensive resin. Therefore, the defrost heater can be configured at low cost.

  The invention according to claim 2 is the invention according to claim 1, wherein the coating material of the lead wire is a thermoplastic resin.

  As a result, the coating of the lead wire can withstand the heat transmitted through the heat absorbing component, can ensure the insulation resistance of the lead wire, and can ensure the reliability of the defrosting heater.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the heat absorbing component includes a through hole through which the lead wire passes, and an end portion of the through hole is defined as the lead wire. The heat-absorbing component is positioned by being locked to the coating.

  With this configuration, the heat absorbing component can be positioned with a simple configuration, and an increase in the number of components can be suppressed.

  In addition, the heat absorbing component can be stored in a lead wire insertion hole of a plug that covers the opening of the glass tube. In such a configuration, it is possible to suppress the displacement of the heat absorbing component, and the heater The reliability of heat transfer suppression in the wire can be increased.

  According to a fourth aspect of the present invention, in the invention of the second or third aspect, the end portion of the lead wire and a thermal fuse disposed in an insulating tube made of a thermoplastic resin are connected in the insulating tube. The insulating tube is sealed.

  With this configuration, the defrost heater and the thermal fuse can be directly connected, and it is not necessary to provide a dedicated lead wire for the thermal fuse. As a result, the number of parts can be reduced, and the connecting work between the lead wires can be simplified, and the assembling workability can be improved.

  Further, the sealing of the insulating tube can protect the connecting portion between the thermal fuse and the lead wire, and can also prevent the influence of corroded substances such as moisture and acid.

  In particular, by using a thermoplastic resin as the material of the lead wire covering and the insulating tube, a welding means can be used for sealing the insulating tube, and the reliability of sealing and work efficiency can be improved. .

  According to a fifth aspect of the present invention, a storage heat source body having a storage space for storing articles is provided with a cooling heat source and a ventilation path for supplying air cooled by the cooling heat source to the storage space, and the cooling It is the cooling storage apparatus which provided the defrost heater as described in any one of Claim 1 to 4 to a heat source so that heat transfer was possible.

  Therefore, the defrost heater can be used for defrosting the cooling heat source, and the defrost function can be configured at low cost.

  Further, since the heater wire has heat resistance and corrosion resistance, a reliable cooling storage device can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a plan view in which a part of the defrosting heater according to Embodiment 1 of the present invention is cut away. FIG. 2 is an enlarged view of a portion A of FIG. 1 in the defrosting heater. FIG. 3 is a perspective view of a heat absorbing component part in the defrosting heater.

  As shown in FIGS. 1 and 2, the defrost heater 1 includes a glass tube 2, a heater wire 3 made of a metal resistor disposed inside the glass tube 2, and a lead wire 4 connected to the heater wire 3. The plug 5 that covers the openings at both ends of the glass tube 2, the lead wire insertion hole 5a for inserting the lead wire 4 provided in the plug 5, and the heater wire 3 and the lead wire 4 in the lead wire insertion hole 5a It is the structure which comprises the heat absorption component 6 provided in between.

  A thermal fuse 7 is electrically connected to the other end of the lead wire 4. The temperature fuse 7 is provided inside an insulating tube 8 made of a thermoplastic resin, and the coating 4b of the lead wire 4 and the insulating tube 8 are welded by high frequency welding at a welded portion 8a of the insulating tube 8. Therefore, the inside of the insulating tube 8 has a sealed structure that blocks inflow of outside air.

  Here, as the heat absorbing component 6, for example, a silicon resin that is a thermosetting resin is preferable, and a hard material such as a ceramic material or a relatively soft material such as silicone rubber can be used. In the first embodiment, silicone rubber is employed.

  As is well known, the lead wire 4 is composed of a core wire 4a such as a copper wire and a coating 4b. The coating 4b is made of heat-resistant vinyl chloride which is a thermoplastic resin in consideration of insulation resistance and cost. .

  As shown in FIG. 3, the heat absorbing component 6 is formed in a cylindrical shape by providing a hole 6 a through which the core wire 4 a of the lead wire 4 passes, and the external appearance is the lead wire insertion hole 5 a provided in the plug 5. It is gently bent along the bend. When the heat absorbing component 6 is formed of a soft material having some flexibility, the heat absorbing component 6 is curved along the shape of the lead wire insertion hole 5a with the insertion into the lead wire insertion hole 5a. .

  The hole diameter R of the hole 6a of the heat absorbing component 6 is set to be larger than the outer diameter r1 of the core wire 4a of the lead wire 4 and smaller than the outer diameter r2 of the coating 4b of the lead wire 4. Accordingly, the heat absorbing component 6 passes through the core wire 4a of the lead wire 4 and comes into contact with the end surface of the covering 4b of the lead wire 4 to be positioned.

  Moreover, the outer diameter of the glass tube 2 is Φ10.5, and the rating of the defrost heater 1 is 100V-130W.

  The defrosting heater 1 is assembled as is well known, but the heater wire 3 and the lead wire 4 are connected and assembled in a state where the heat absorbing component 6 is attached to the lead wire 4 in advance.

  Thus, by providing the heat absorbing component 6 between the heater wire 3 and the lead wire 4, the temperature of the heat transmitted from the heater wire 3 to the coating 4 b of the lead wire 4 is alleviated. The heat resistance required for the coating 4b can be relaxed, and a material such as heat-resistant vinyl chloride that can be processed at low cost such as welding can be used.

  Therefore, since the defrosting heater 1 and the thermal fuse 7 are directly connected to the single lead wire 4, it is not necessary to connect a lead wire having a different coating material as in the prior art, and a connector associated with the connection. Connection parts such as the above are also unnecessary, and the number of parts and assembly man-hours can be reduced and can be produced at low cost.

  Furthermore, since the insulation material of the insulating tube 8 and the lead wire 4 can be made the same, it is possible to seal the thermal fuse 7 by welding, ensuring reliability against moisture and dust, and stabilizing the quality. Can be measured.

  Moreover, since the defrosting heater 1 and the thermal fuse 7 can be attached as a unit structure to a main device such as a cooler (not shown), work associated with incorporation into the main device can be greatly improved, and work efficiency can be improved. Can be improved.

  Further, when the heat absorbing component 6 is attached to the lead wire 4, it is possible to attach the heat absorbing component 6 using a new component. However, in the first embodiment, the lead wire 4 is brought into contact with the end surface of the coating 4 b. The heat-absorbing component 6 is positioned using the plug, and is fitted into the lead wire insertion hole 5a of the plug 5 to complete the mounting. When mounting the heat-absorbing component 6, the number of components can be reduced and the work man-hours can be simplified. Can be

  Thus, the defrost heater 1 can make the insulation coating material of the lead wire 4 into an inexpensive thermoplastic resin by relaxing the heat transfer from the heater wire 3 to the lead wire 4. Therefore, the lead wire 4 can be used as the lead wire of the thermal fuse 7 that requires airtightness, and the energization circuit configuration of the defrost heater 1 is simplified by unitizing the defrost heater 1 and the thermal fuse 7. It can be made.

  The lead wire 4 is connected to both ends of the heater wire 3, but in the first embodiment, the lead wire 4 connected to one side of the heater wire 3 has been mainly described for convenience of explanation. .

  In the first embodiment, the other lead wire 4c connected to the heater wire 3 is similarly provided with a heat absorbing component 6 so that the coating of the lead wire 4c is inexpensive and reliable in heat resistance. Although vinyl is adopted, if the balance with the thermal fuse 7 is not taken into consideration, a thermosetting resin such as a silicon resin having a high heat resistance can be used for covering the other lead wire 4c as usual. .

(Embodiment 2)
FIG. 4 is a schematic longitudinal sectional view of a main part of the refrigerator equipped with the defrosting heater according to the first embodiment. Here, the same components as those of the first embodiment are denoted by the same reference numerals and will be described with reference to FIGS. 1 to 3.

  In FIG. 4, a freezer compartment (corresponding to the storage space of the present invention) 13 and a refrigerator compartment (corresponding to the storage space of the present invention) 14 partitioned by the partition wall 12 are formed inside the refrigerator body 11. A freezer compartment door 15 and a refrigerator compartment door 16 are provided on the opening surfaces of the compartment 13 and the refrigerator compartment 14, respectively.

  In addition, a cooling chamber (corresponding to a ventilation path of the present invention) 19 in which an evaporator (corresponding to the cooling heat source of the present invention) 17 and a circulation blower 18 are arranged is provided on the back of the freezing chamber 13. In the upper part, a discharge port 19a for discharging cool air into the freezer compartment 13 is provided.

  Furthermore, the partition wall 12 is provided with a freezer compartment suction port 20 and a refrigerator compartment suction port 21 communicating with the cooling chamber 19.

  The defrost heater 1 described in the first embodiment is provided below the evaporator 17, and the defrosting heater 1 and the evaporator 17 are removed between the defroster 1 and the evaporator 17 during the defrosting operation of the evaporator 17. A cover 22 that prevents dripping of frost water on the defrost heater 1 is provided, and a bottom plate 23 that reflects the heat of the defrost heater 1 toward the evaporator 17 is provided below the defrost heater 1. Yes.

  Furthermore, the bottom of the cooling chamber 19 is provided with a tub 24 that receives defrost water generated during the defrosting operation of the evaporator 17 and a drain port 25 that drains the defrost water collected in the tub 24. .

  In the above configuration, when the refrigerator is operated and frost formation occurs in the evaporator 17, the cooling operation is stopped and the defrosting operation is performed. About the operation content of a refrigerator, since it may be a well-known content, description here is abbreviate | omitted.

  This defrosting operation energizes the defrosting heater 1 and melts the frost attached to the evaporator 17 and the like due to the heat generated by the defrosting heater 1, and is the same as the conventional one.

  During the defrosting operation, the heat of the heater wire 3 is transferred to the temperature fuse 7 side through the lead wire 4 (core wire 4a). In the case of the rated defrost heater 1 described in the first embodiment, the temperature of the core 4a portion of the lead wire 4 where the heat recovery component 6 is located is about 150 ° C. However, by providing the heat recovery component 6, the lead The heat transferred to the coating 4b of the wire 4 is 105 ° C. or less, which is the upper limit value of the use temperature of the heat-resistant vinyl chloride.

  Accordingly, the coating 4b of the lead wire 4 is not melted by the heat of the heater wire 3, and the temperature reaching the thermal fuse 7 through the core wire 4a of the lead wire 4 is also increased with the length of the lead wire 4. The temperature does not decrease and does not exceed the operating temperature (for example, 75 ° C.) of the thermal fuse 7.

  As described above, the refrigerator equipped with the defrosting heater 1 of the first embodiment can maintain safety, and can make use of the cost of the defrosting heater 1 to configure the defrosting function at low cost. .

  Further, since the connecting portion of the lead wire 4 to the thermal fuse 7 is in the sealed insulating tube 8, it is not affected by the corrosive substance generated from the surface of the evaporator 17 during the defrosting operation. Therefore, the corrosion resistance treatment for preventing the corrosion of the connection terminals is not required, and the structure can be made inexpensive and high in corrosion resistance, and the reliability of the refrigerator can be improved.

  In addition, the structure of the said refrigerator shows an example of a well-known structure, and the refrigerator made into a slightly different structure in consideration of usability etc. is also well-known. Those skilled in the art can easily understand that the present invention is applicable to such a refrigerator.

  As described above, since the defrosting heater according to the present invention can lower the coating temperature of the lead wire, the coating material of the lead wire can be made an inexpensive thermoplastic resin and integrated with the thermal fuse. It can be used as a defrosting heater, and can be widely applied to a refrigerator to which the defrosting heater is applied, or a so-called cooling storage device such as a showcase or a vending machine.

The top view which notched some defrost heaters in Embodiment 1 of this invention The enlarged view of the A section of FIG. 1 of the defrosting heater in Embodiment 1 The perspective view of the heat absorption component part of the defrost heater in Embodiment 1 The schematic longitudinal cross-sectional view of the principal part of the refrigerator which mounts the defrost heater of Embodiment 1 which shows Embodiment 2 of this invention. Schematic longitudinal sectional view of the main part of a refrigerator equipped with a conventional defrost heater The top view which shows the structure of the conventional defrost heater Plan view showing the structure of a conventional thermal fuse assembly

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Defrost heater 2 Glass tube 3 Heater wire 4 Lead wire 4a Core wire 4b Cover 4c Lead wire 5 Plug 5a Lead wire insertion hole 6 Heat absorption part 7 Thermal fuse 8 Insulation tube 8a Welding part 11 Refrigerator body 13 Freezer compartment (storage space)
14 Cold room (storage space)
17 Evaporator (cooling heat source)
19 Cooling room (ventilation path)

Claims (5)

  A glass tube, a heater wire installed inside the glass tube, a lead wire connected to the heater wire, and a plug that covers both end openings of the glass tube, and the lead wire is inserted into the plug A defrosting heater provided with a lead wire insertion hole, wherein a heat absorbing component is provided between the heater wire and the covering of the lead wire.   The defrost heater according to claim 1, wherein the lead wire coating material is a thermoplastic resin.   3. The heat absorbing component according to claim 1, wherein the heat absorbing component includes a through hole through which the lead wire passes, and an end portion of the through hole is engaged with a coating of the lead wire to position the heat absorbing component. Defrost heater as described.   The defrost heater according to claim 2 or 3, wherein a temperature fuse arranged in an end portion of the lead wire and an insulating tube made of a thermoplastic resin is connected in the insulating tube, and the insulating tube is sealed.   The storage device main body having a storage space for storing articles is provided with a cooling heat source and a ventilation path for supplying air cooled by the cooling heat source to the storage space, and the cooling heat source further includes: The cooling storage apparatus which provided the defrost heater as described in any one so that heat transfer was possible.

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