Cooling storage

Abstract

To provide a cooling storage capable of detecting abnormality of a defrosting heater at an early stage, without being greatly influenced by radiation heat of the defrosting heater.SOLUTION: A cooling storage includes: a defrosting heater 52 which melts frost generated by a cooler 42; an overheat detection tool 54 which can detect heat in the periphery so as to prevent overheating by the defrosting heater 52; and a cover member 68 which covers at least a part of the defrosting heater 52. The cover member 68 has: a heater opposing part 70 which opposes to the defrosting heater 52, and receives radiation heat from the defrosting heater 52; and extension parts 73, 75 which are portions continuously molded so as to extend from the heater opposing part 70, and extend in a direction being separated from the defrosting heater 52. The overheat detection tool 54 is provided at the extension part 75, and detects the heat conducted to the extension parts 73, 75 from the heater opposing part 70.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a cooling refrigerator.

Background Art

[0002] As disclosed in Patent Document 1 below, conventionally, in a cooling refrigerator, frost may adhere during cooling operation, and a defrost heater for melting the frost is provided. In order to deal with an abnormality such as the defrost heater overheating too much, for example, a sensor for detecting the ambient temperature, a fuse for detecting the ambient heat and performing a disconnection process on the circuit, etc., a heat detection tool capable of detecting heat is provided near the defrost heater.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the temperature of the defrost heater is high, the overheat detection tool can detect the overheated state without problem even at a position relatively far from the defrost heater. However, when the temperature of the defrost heater is relatively low, the overheat detection tool needs to be arranged relatively close to the defrost heater, but it cannot be arranged at a location directly receiving the radiant heat of the defrost heater.

[0005] In view of such circumstances, the present invention has been made, and an object thereof is to provide a cooling refrigerator capable of early detecting an abnormality of a defrost heater without being greatly affected by the radiant heat of the defrost heater.

Means for Solving the Problems

[0006] In order to solve the above problems, the refrigerated storage disclosed in the present application has the following configuration. (1) A storage chamber, A cooler for cooling the air flowing into the storage chamber, A defrost heater for melting the frost generated by the cooler, An overheat detector capable of detecting ambient heat to prevent overheating by the defrost heater, A cover member covering at least a part of the defrost heater, and the cover member has a heater facing portion that faces the defrost heater and receives radiant heat from the defrost heater, and a portion that is continuously formed so as to extend from the heater facing portion, and an extending portion that extends in a direction away from the defrost heater, and the overheat detector is provided on the extending portion and is characterized by detecting heat conducted from the heater facing portion to the extending portion, a refrigerated storage.

[0007] Further, in the refrigerated storage having the above configuration, it is possible to adopt the following various modes.

[0008] (2) Including the cooler, and provided with a refrigeration cycle type cooling device in which a flammable refrigerant circulates, the defrost heater has a surface temperature equal to or lower than a temperature set lower than the ignition temperature of the flammable refrigerant, the refrigerated storage according to item (1).

[0009] (3) The heater facing portion is erected so as to cover the side of the defrost heater, the extending portion has a pedestal portion that extends from the heater facing portion toward the side opposite to the defrost heater, the overheat detector is attached to the pedestal portion, the refrigerated storage according to item (1) or (2).

[0010] (4) A first cover member which is the cover member covering the side of the defrosting heater, and a second cover member which is the cover member covering the upper side of the defrosting heater, are provided. In the first cover member, the heater facing portion is a side facing portion facing the side of the defrosting heater, and the extending portion has an upward extending portion extending upward from the side facing portion and a pedestal portion extending from the upper end of the upward extending portion toward the side opposite to the defrosting heater. In the second cover member, the heater facing portion is an upper facing portion facing the upper side of the defrosting heater, and the extending portion is a standing wall portion standing upward from the edge portion on the side of the side facing portion in the upper facing portion. The upward extending portion of the first cover member and the standing wall portion of the second cover member are overlapped. The overheat detector is arranged along the corner portion formed by the standing wall portion and the pedestal portion, and detects heat from both the standing wall portion and the pedestal portion. The cooling storage refrigerator according to any one of items (1) to (3).

[0011] (5) A circulation fan for circulating air between the cooler and the storage chamber, and a holding member for holding the circulation fan are provided. The holding member is configured to hold the defrosting heater below the circulation fan, and has a roof portion formed to project between the circulation fan and the defrosting heater to receive defrosting water from the circulation fan. The roof portion functions as the upper facing portion, and the holding member functions as the second cover member. The cooling storage refrigerator according to item (4).

[0012] (6) The defrosting heater is in a longitudinal shape. The cover member has a pair of holding portions for holding the defrosting heater at both ends in the longitudinal direction, and has an upper facing portion facing the upper side of the defrosting heater as the heater facing portion. The extending portion extends outward from the holding portion from one end in the longitudinal direction in the upper facing portion. The cooling storage refrigerator according to item (1) or (2), wherein the overheat detector is attached to the upper surface side of the extending portion.

Advantages of the Invention

[0013] According to the present invention, it is possible to provide a cooling storage refrigerator capable of early detecting an abnormality of a defrost heater without being greatly affected by the radiant heat of the defrost heater.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

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Figure 20

Mode for Carrying Out the Invention

[0015] ≪Embodiment 1≫ <Schematic Configuration of the Cooling Storage> The cooling storage 10 according to the first embodiment of the present invention will be described with reference to Figs. 1 to 5. In some of the drawings, the directions are indicated by the symbols F, B, L, R, U, D, which represent the front side (front), rear side (rear), left side, right side, upper side, and lower side when the cooling storage 10 is viewed from the front, respectively.

[0016] As shown in Fig. 1, the cooling storage 10 of the present embodiment is a two-door horizontal freezer-refrigerator (under-counter freezer-refrigerator), and includes a horizontally long storage body 12, a pair of double-opening type opening / closing doors 14L and 14R, and a top plate 16 disposed above the storage body 12. The storage body 12 includes a heat-insulating box body 20 that opens forward, and a center pillar 22 that is attached in a state of extending vertically in the center of the front opening of the heat-insulating box body 20. The pair of opening / closing doors 14L and 14R are heat-insulating doors filled with a heat-insulating material inside, and open and close the left and right openings of the center pillar 22 in the heat-insulating box body 20.

[0017] As shown in Fig. 2, the heat-insulating box body 20 is composed of an outer box 20A formed by processing a stainless steel plate into a box shape, an inner box 20B, and a heat-insulating material 20C foamed and filled between the outer box 20A and the inner box 20B. On the back side of the center pillar 22, a partition wall 24 is provided to divide the inside of the heat-insulating box body 20 into left and right spaces. This partition wall 24 is also a heat-insulating wall in which a heat-insulating material is filled inside an outer profile made of stainless steel plate. That is, the inside of the heat-insulating box body 20 is partitioned into two airtight left and right spaces S1 and S2 by the center pillar 22 and the partition wall 24.

[0018] Most of the first space S1 on the left side of the heat-insulating box body 20 is a first storage chamber R1 for storing items. However, a partition panel 26 is arranged on the left side of the first storage chamber R1, and a first cooler chamber R2 is partitioned and formed. The partition panel 26 is provided with a suction port 26A at the lower end side for sucking the air in the first storage chamber R1 into the first cooler chamber R2, and a blowout port 26B at the upper end side for blowing the air in the first cooler chamber R2 into the first storage chamber R1. Similarly, most of the second space S2 on the right side of the heat-insulating box body 20 is a second storage chamber R3 for storing items. However, a partition panel 28 for partitioning the second space S2 is arranged so as to be aligned on the right side of the partition wall 24, and a second cooler chamber R4 is partitioned and formed between the partition wall 24 and the partition panel 28. This partition panel 28 is also provided with a suction port 28A at the lower end side for sucking the air in the second storage chamber R3 into the second cooler chamber R4, and a blowout port 28B at the upper end side for blowing the air in the second cooler chamber R4 into the second storage chamber R3.

[0019] The storage body 12 also includes a plurality of panels assembled to the left of the heat-insulating box body 20. As shown in Figs. 1 to 3, those plurality of panels are side panels 30, a base panel 31, a front panel 32, etc. The storage body 12 has a machine room R5 formed by those panels 30, 31, 32, the side wall portion 20D on the left side of the heat-insulating box body 20, the top plate 16, etc.

[0020] In the machine room R5, as shown in FIGS. 2 and 3, a part of the cooling device 34 (compressor 38, condenser 40, condenser fan 41) for cooling the storage rooms R1 and R3, and a control device 36 that controls the cooling storage cabinet 10 are accommodated. The cooling device 34 includes a compressor 38, a condenser 40, an expansion valve, a first cooler 42 in the first cooler chamber R2, and a second cooler 44 in the second cooler chamber R4. In the cooling storage cabinet 10 of the present embodiment, the first storage room R1 is a freezing chamber for freezing stored items, the second storage room R3 is a refrigerating chamber for refrigerating stored items, and the first storage room R1 and the second storage room R3 can be controlled to different temperatures from each other. The compressor 38, the condenser 40, and the first cooler 42 are connected to each other via a refrigerant pipe 46, and a first cooling circuit for circulating the refrigerant is configured. The compressor 38, the condenser 40, and the second cooler 44 are connected to each other via a refrigerant pipe 47, and a second cooling circuit is configured. In the present embodiment, as a consideration for the global environment, natural refrigerants (flammable refrigerants) such as isobutane and propane are used as the refrigerants circulated in the refrigerant pipes 46 and 47.

[0021] <Configuration in the First Space> First, the configuration in the first space S1 will be described. In the first cooler chamber R2 in the first space S1, a circulation fan 48 driven by a motor is accommodated together with the first cooler 42. This circulation fan 48 is arranged between the first cooler 42 and the air outlet 26B. During the cooling operation, due to the drive of the circulation fan 48, the air in the first storage room R1 is sucked into the first cooler chamber R2 from the suction port 26A, and then the cold air generated by heat exchange while passing through the first cooler 42 is blown out from the air outlet 26B into the first storage room R1. Thereby, the air in the first space S1 is circulated, and the inside of the first storage room R1 is cooled.

[0022] In addition, when the door 14L is opened and closed, moist air may enter the first storage chamber R1. When the moist air flows into the first cooler chamber R2, frost will adhere to the inside of the first cooler chamber R2. In particular, frost easily adheres to the first cooler 42 and the circulation fan 48. In order to melt the frost adhering to the first cooler 42 and the circulation fan 48, two defrost heaters 50, 52 are also accommodated in the first cooler chamber R2. As described above, in the cooling refrigerator 10 of the present embodiment, since a flammable refrigerant is used as the refrigerant, it is necessary to consider the safety in the case where the flammable refrigerant leaks from the first cooler 42. The defrost heaters 50, 52 need to have a lower surface temperature compared to a cooling refrigerator using a conventional chlorofluorocarbon refrigerant. Therefore, in the present embodiment, the defrost heaters 50, 52 are formed as longitudinal double glass tube heaters, and their surface temperature is controlled to be equal to or lower than a temperature (set temperature) 100K lower than the ignition temperature of the refrigerant.

[0023] Furthermore, in the defrost heaters 50, 52, in order to avoid a situation where some abnormality occurs and the above set temperature is greatly exceeded and overheated, an overheat detector 54 capable of detecting ambient heat is provided near the defrost heaters 50, 52 (see FIGS. 4 to 8). In the present embodiment, the overheat detector 54 is a thermal fuse (hereinafter, may be simply referred to as "fuse 54"), and is provided on the circuit of the two defrost heaters 50, 52 connected in series or in parallel. When the fuse 54 detects that the ambient temperature has reached or exceeded the operating temperature, it cuts off the circuit and prohibits power supply to the defrost heaters 50, 52.

[0024] As described above, the cooling refrigerator 10 of the present embodiment has a lower surface temperature of the defrost heaters 50, 52 compared to a cooling refrigerator using a conventional chlorofluorocarbon refrigerant, so it is difficult to detect the above overheated state. The cooling refrigerator 10 of the present embodiment is characterized by the mounting structure of the fuse 54, which is an overheat detector, so that the fuse 54 operates properly. Hereinafter, the structure around the fuse 54 will be described in detail with reference to FIGS. 4 to 8.

[0025] In the cooling refrigerator 10 of the present embodiment, the circulation fan 48, the defrost heaters 50 and 52, and the fuse 54 are unitized and are housed in the first cooler chamber R2 in a state where they are assembled. Specifically, as shown in FIGS. 4 and 5, the circulation fan 48, the defrost heaters 50 and 52, and the fuse 54 are attached to a bracket 60 and unitized. The upper side of the first cooler chamber R2 is partitioned and formed by a cooler box 62 that holds the first cooler 42. By fixing the above-mentioned bracket 60 to the cooler box 62, the circulation fan 48, the defrost heaters 50 and 52, and the fuse 54 are housed in the first cooler chamber R2.

[0026] The bracket 60 is composed of a first holding member 64 and a second holding member 66. The first holding member 64 generally extends in the horizontal direction and holds the first defrost heater 50. The second holding member 66 is fastened to the right end of the first holding member 64 in a state of extending upward and holds the circulation fan 48 and the second defrost heater 52. That is, the bracket 60 generally forms an L shape as a whole. The bracket 60 is inserted and fixed to the cooler box 62 from the right side of the first cooler 42. Incidentally, the circulation fan 48 has a plurality of blades that are rotationally driven by a motor, and in FIGS. 4 to 6, the movable range of those blades is shown in a cylindrical shape.

[0027] The first holding member 64 is formed by bending a single plate material, has a rectangular frame shape that is long in the front-rear direction, and has openings on the upper and lower surfaces. Specifically, as shown in FIG. 4, the first holding member 64 includes an upper surface portion 64c in which openings 64a and 64b are formed, and a front frame portion 64d, a rear frame portion 64e, a right frame portion 64f, and a left frame portion 64g that extend downward from the four sides of the outer edge of the upper surface portion 64c, so that the upper and lower surfaces are open. And the first holding member 64 is fastened to the second holding member 66 at the right frame portion 64f. When the bracket 60 is fixed to the cooler box 62, the first holding member 64 is positioned directly below the first cooler 42 and allows the air sucked from the first storage chamber R1 to pass through and flow into the first cooler 42. The first holding member 64 holds the first defrost heater 50 between the front frame portion 64d and the rear frame portion 64e. The upper surface portion 64c of the first holding member 64 has a portion between the two openings 64a and 64b extending in the front-rear direction, and the first defrost heater 50 is disposed directly below the roof portion 64h that is that portion. That is, the roof portion 64h prevents the defrosting water from the first cooler 42 from falling onto the first defrost heater 50.

[0028] The second holding member 66 has a first plate portion 66b provided with a first opening 66a and a second plate portion 66c spaced to the right from the first plate portion 66b to which the circulation fan 48 is attached. When the bracket 60 is fixed to the cooler box 62, the right surface of the first cooler 42 covers the first opening 66a of the first plate portion 66b, and as shown in FIG. 2, the circulation fan 48 is positioned above the right upper side of the first cooler 42. Further, as shown in FIG. 6, a second opening 66d extending in the front-rear direction is formed in the second plate portion 66c below the circulation fan 48, and the second defrost heater 52 is disposed in the second opening 66d. Although it will be described in detail later, the second defrost heater 52 is attached to the heater cover 68, and the heater cover 68 is fastened to the second plate portion 66c, so that the second defrost heater 52 is held by the second holding member 66. When the bracket 60 is fixed to the cooler box 62, the second defrost heater 52 is positioned on the side of the first cooler 42 and radiates heat toward the first cooler 42. Further, the second defrost heater 52 is also positioned below the circulation fan 48, and the frost adhering to the circulation fan 48 can also be melted.

[0029] In addition, as shown in FIGS. 4, 6, and 7, the second holding member 66 has a roof portion 66e formed so as to project between the circulation fan 48 and the second defrost heater 52 so that the defrost water from the circulation fan 48 does not fall onto the second defrost heater 52. The roof portion 66e is formed by being bent along the upper edge of the second opening 66d in the second plate portion 66c and is provided in a state of being inclined downward toward the first plate portion 66b. In addition, the roof portion 66e also functions as a heater facing portion that faces the second defrost heater 52 and receives radiant heat from the second defrost heater 52.

[0030] As shown in FIG. 6, silicon caps 53 are attached to each of the both ends of the second defrosting heater 52. The heater cover 68 holds the second defrosting heater 52 at the pair of caps 53. Specifically, the heater cover 68 has a cover main body portion 70 that extends in the front-rear direction and covers the right and lower sides of the second defrosting heater 52, and a pair of holding portions 71 and 72 that are bent and formed from both ends of the cover main body portion 70 in the front-rear direction. By engaging each of the pair of caps 53 of the second defrosting heater 52 with each of the pair of holding portions 71 and 72, the second defrosting heater 52 is held. As shown in FIG. 7, the cover main body portion 70 has a portion with a U-shaped cross section, and its lower end portion covers the lower side of the second defrosting heater 52, and the upper side portion protrudes rightward from the second opening 66d and covers the side of the second defrosting heater 52. The heater cover 68 has a pair of mounting portions 73 extending upward from the upper edge of the cover main body portion 70 protruding rightward from the second opening 66d at both ends in the front-rear direction, and at the pair of mounting portions 73, it is fastened to the right surface of the second plate portion 66c of the second holding member 66 by screws 74.

[0031] Further, the heater cover 68 has a pedestal portion 75 that is bent and formed from the upper end of the mounting portion 73 and extends horizontally rightward toward the side opposite to the second defrosting heater 52. The above-described fuse 54 is attached to the upper surface side of this pedestal portion 75. In a state where the heater cover 68 is fastened to the second holding member 66, as shown in FIGS. 7 and 8, a portion 66c1 (hereinafter, may be referred to as a "vertical wall portion 66c1") extending upward from the base end of the roof portion 66e of the second plate portion 66c overlaps with the mounting portion 73 of the heater cover 68, and the pedestal portion 75 of the heater cover 68 is in a state of standing upright from the vertical wall portion 66c1. And the fuse 54 is arranged along the corner portion formed by the vertical wall portion 66c1 and the pedestal portion 75, and is fixed by being pressed against the right surface of the vertical wall portion 66c1 by a clip 76. Also, the fuse 54 is in contact with the pedestal portion 75, and the pedestal portion 75 prevents the fuse 54 from falling off.

[0032] From the above configuration, the heater cover 68 has a cover main body portion 70 that functions as a heater facing portion that faces the second defrost heater 52 and receives radiant heat from the second defrost heater 52. The radiant heat received by the cover main body portion 70 is transmitted to the mounting portion 73 and the pedestal portion 75 as the extending portion. That is, the fuse 54 is configured to detect the heat transmitted to the pedestal portion 75. Also, as described above, in the second holding member 66, the roof portion 66e functions as a heater facing portion, and the radiant heat received by the roof portion 66e is transmitted to the standing wall portion 66c1, and the fuse 54 is also configured to detect the heat transmitted to this standing wall portion 66c1. From the above configuration, a part of the cover main body portion 70 of the heater cover 68 functions as a side facing portion, and the heater cover 68 functions as a first cover member, and the standing wall portion 66c1 of the second holding member 66 functions as an upper facing portion, and the second holding member 66 functions as a second cover member.

[0033] As described above, the refrigerating storage 10 of the present embodiment includes a first storage chamber R1, a first cooler 42 that cools the air flowing into the first storage chamber R1, a second defrost heater 52 that melts the frost generated by the first cooler 42, a thermal fuse 54 as an overheat detector that can detect the ambient heat to prevent overheating by the second defrost heater 52, and a heater cover 68 (second holding member 66) as a cover member that covers at least a part of the second defrost heater 52. The heater cover 68 (second holding member 66) has a cover main body portion 70 (roof portion 66e) that is a heater facing portion that faces the second defrost heater 52 and receives radiant heat from the second defrost heater 52, and a portion that is continuously formed so as to extend from the cover main body portion 70 (roof portion 66e) that is the heater facing portion, and is an extending portion that extends in a direction away from the second defrost heater 52, the mounting portion 73 and the pedestal portion 75 (standing wall portion 66c1). The thermal fuse 54, which is an overheat detector, is provided on the pedestal portion 75 (standing wall portion 66c1) and is characterized by detecting the heat conducted from the cover main body portion 70 (roof portion 66e) to the mounting portion 73 and the pedestal portion 75 (standing wall portion 66c1).

[0034] In the refrigerator 10 of this embodiment, since the fuse 54 is provided outside the portion covering the second defrost heater 52 by the heater cover 68 (second holding member 66), the infrared rays of the second defrost heater 52 are not directly irradiated onto the fuse 54. Therefore, when the second defrost heater 52 is operating normally, the fuse 54 does not reach the operating temperature, and a situation where the fuse 54 malfunctions can be avoided. And the fuse 54 is provided with respect to the pedestal portion 75 (standing wall portion 66c1) as an extending portion to which the radiant heat received by the cover main body portion 70 (roof portion 66e), which is the heater facing portion, is transmitted, and it is possible to detect relatively early that the second defrost heater 52 is in an overheated state.

[0035] Note that, as described above, the refrigerator 10 of this embodiment uses a flammable refrigerant, and since the surface temperature of the second defrost heater 52 is set relatively low, if there are a plurality of members between the second defrost heater 52 and the fuse 54, even when an abnormality occurs in the second defrost heater 52 and it enters an overheated state, there is a risk that the fuse 54 may not be able to detect the heat, or even if it can detect the heat, the detection may be delayed. On the other hand, according to the refrigerator 10 of this embodiment, the radiant heat received by the cover main body portion 70 and the roof portion 66e is transmitted to the pedestal portion 75 and the standing wall portion 66c1, and the fuse 54 can detect this heat. Therefore, it is possible to appropriately detect the overheated state of the second defrost heater 52 and perform the circuit interruption process at an appropriate timing.

[0036] Also, in the refrigerator 10 of this embodiment, the cover main body portion 70 of the heater cover 68, which is the heater facing portion, is erected so as to cover the side of the second defrost heater 52, and the extending portion has a pedestal portion 75 that extends from the cover main body portion 70 toward the side opposite to the second defrost heater 52, and the fuse 54, which is the overheat detector, is configured to be attached to the pedestal portion 75.

[0037] With such a configuration, by moving the proximal end of the pedestal portion 75 upward or increasing the length of the pedestal portion 75, the distance from the second defrost heater 52 can be easily changed, and it is easy to arrange the fuse 54 at an appropriate position with respect to the second defrost heater 52. Note that, from the viewpoint of reducing the influence of the radiant heat from the second defrost heater 52, the surface of the pedestal portion 75 to which the fuse, which is an overheat detector, is attached is preferably the surface on the side opposite to the second defrost heater 52, as in the case of the cooling storage cabinet 10 of the present embodiment. Furthermore, since heat tends to be transmitted upward, it is desirable that the overheat detector be provided on the upper surface side of the pedestal portion 75, as in the case of the cooling storage cabinet 10 of the present embodiment.

[0038] Furthermore, the cooling storage cabinet 10 of the present embodiment includes a heater cover 68 as a first cover member that covers the side of the second defrost heater 52, and a second holding member 66 as a second cover member that covers the upper side of the second defrost heater 52. The heater cover 68, which is the first cover member, has a cover main body portion 70 that includes a side facing portion facing the side of the second defrost heater 52, and an extending portion that includes an attachment portion 73 as an upward extending portion extending upward from the side facing portion, and a pedestal portion 75 extending from the upper end of the attachment portion 73 toward the side opposite to the second defrost heater 52. The second holding member 66, which is the second cover member, has a roof portion 66e as an upward facing portion facing the upper side of the second defrost heater 52, and an extending portion that includes a standing wall portion 66c1 standing upward from the edge portion on the side of the side facing portion in the roof portion 66e. The attachment portion 73 of the heater cover 68 and the standing wall portion 66c1 of the second holding member 66 are overlapped with each other, and the fuse 54 is arranged along the corner portion formed by the standing wall portion 66c1 and the pedestal portion 75, and is configured to detect heat from both the standing wall portion 66c1 and the pedestal portion 75.

[0039] With such a configuration, the cooling refrigerator 10 of the present embodiment includes two members that transfer the radiant heat received by the second defrost heater 52, and the locations where the radiant heat is transmitted in each of these two members 66 and 68 are located on both the side and the bottom of the fuse 54. Therefore, an abnormality of the second defrost heater 52 can be detected earlier and more reliably.

[0040] Note that through holes 73a and 66c2 for engaging the clip 76 are formed in the overlapping portion of the attachment portion 73 of the heater cover 68 and the vertical wall portion 66c1 of the second holding member 66, as shown in FIGS. 6 and 7. Since the larger the size of these through holes 73a and 66c2, the more difficult it is for heat to be transmitted, the temperature of the heat transmitted to the fuse 54 can be adjusted by adjusting the size of the through holes 73a and 66c2.

[0041] <Prevention of rotation of the defrost heater> Here, the attachment structure of the second defrost heater 52 to the heater cover 68 and the attachment structure of the first defrost heater 50 to the first holding member 64 will be described. First, the defrost heaters 50 and 52 are double glass tube heaters and have decompression hole marks 50a and 52a when sealing decompression holes for decompressing the space between the glass tubes. The decompression hole marks 50a and 52a are formed to protrude radially from the cylindrical glass tube bodies 50b and 52b. Therefore, when the defrost heaters 50 and 52 rotate around the axis while being held by the heater cover 68 and the first holding member 64, there is a risk that the decompression hole marks 50a and 52a will come into contact with the heater cover 68 and the first holding member 64. Also, as described above, caps 51 and 53 are attached to each of the both ends of the defrost heaters 50 and 52. These caps 51 and 53 insulate and enclose the internal heating wires and are for taking out the wirings 50c and 52c connected to each end to the outside. And, so that defrost water does not enter the holes for taking out the wirings 50c and 52c, the caps 51 and 53 are formed with eaves 51a and 53a that slope downward toward the tip at the tip, and the wirings 50c and 52c are taken out from the lower surface side of the eaves 51a and 53a. Therefore, when the defrost heaters 50 and 52 rotate around the axis while being held by the heater cover 68 and the first holding member 64, the eaves 51a and 53a do not function, and there is a risk that defrost water will penetrate into the defrost heaters 50 and 52.

[0042] Therefore, the cooling refrigerator 10 of the present embodiment is configured to be able to reliably suppress the rotation around the axes of the defrost heaters 50 and 52. First, the attachment structure of the second defrost heater 52 to the heater cover 68 will be described with reference to FIGS. 9 and 10. As described above, the heater cover 68 holds both end portions of the second defrost heater 52 at a pair of holding portions 71 and 72. Insertion holes 71a and 72a for inserting the tips of the caps 53 are formed in these holding portions 71 and 72. Specifically, the cap 53 has a cap main body portion 53b that is open at one end and into which the glass tube main body 52b is fitted, and a protruding portion 53c that protrudes from the other end of the cap main body portion 53b. The protruding portion 53c has a cylindrical shape with an outer diameter smaller than the outer diameter of the cap main body portion 53b. However, the base end portion 53c1 of the protruding portion 53c is formed in a rectangular shape in the upper half, and has a shape that protrudes radially from the outer peripheral surface of the cylindrical portion 53c2, which is the tip side portion of the protruding portion 53c. As shown in FIG. 10, the insertion holes 71a and 72a formed in the holding portions 71 and 72 of the heater cover 68 have the same shape as the outer shape of the base end portion 53c1. Therefore, the base end portion 53c1 and the insertion holes 71a and 72a are engaged with almost no gap therebetween, and the rotation of the base end portion 53c1 with respect to the insertion holes 71a and 72a is suppressed, so that the rotation around the axis of the second defrost heater 52 is suppressed.

[0043] Next, the case of attaching the second defrosting heater 52 to the heater cover 68 will be described. Among the pair of holding portions 71 and 72, the front holding portion 71 has a slit-shaped notch 71b that extends laterally (to the left) from the upper end of the insertion hole 71a and opens at the edge. Further, in the front holding portion 71, the lower portion of the notch 71b is a bent portion 71c. As shown in FIG. 9, by tilting the bent portion 71c forward, an opening having substantially the same width as the inner dimension in the vertical direction of the insertion hole 71a can be formed. Therefore, by tilting the bent portion 71c, after inserting the rear end of the second defrosting heater 52 into the insertion hole 72a of the rear holding portion 72, the front end of the second defrosting heater 52 can be inserted into the insertion hole 71a from the side (left). Finally, by returning the bent portion 71c to its original position, the attachment of the second defrosting heater 52 to the heater cover 68 is completed. Incidentally, after attaching the heater cover 68 holding the second defrosting heater 52 to the second holding member 66 in the state shown in FIG. 6, the roof portion 66e of the second holding member 66 exists above the second defrosting heater 52. However, since the direction of attaching and detaching the second defrosting heater 52 is lateral, it is also possible to remove the second defrosting heater 52 from the heater cover 68 without removing the heater cover 68 from the second holding member 66.

[0044] Subsequently, the attachment structure of the first defrosting heater 50 to the first holding member 64 will be described with reference to FIGS. 11 and 12. The caps 51 attached to both ends of the first defrosting heater 50 are the same as the caps 53 of the second defrosting heater 52. Since the attachment structure of the first defrosting heater 50 to the first holding member 64 is basically the same as the attachment structure of the second defrosting heater 52 to the heater cover 68 described above, it will be briefly described.

[0045] As described above, the first holding member 64 holds both ends of the first defrosting heater 50 at the front frame portion 64d and the rear frame portion 64e. Insertion holes 64d1 and 64e1 having the same outer shape as the base end portion 51c1 of the cap 51 are formed in the front frame portion 64d and the rear frame portion 64e. Therefore, the base end portion 51c1 and the insertion holes 64d1 and 64e1 are engaged with almost no gap therebetween, and the rotation of the base end portion 51c1 with respect to the insertion holes 64d1 and 64e1 is suppressed, so that the rotation of the first defrosting heater 50 around its axis is suppressed.

[0046] And the front frame portion 64d has a bent portion 64d2 for temporarily widening the opening of the insertion hole 64d1. This bent portion 64d2 is in the shape of a sheet extending downward and can be bent along the upper end as shown in FIG. 11. Therefore, by lifting the bent portion 64d2, after inserting the rear end of the first defrosting heater 50 into the insertion hole 64e1 of the rear frame portion 64e, the front end of the first defrosting heater 50 can be inserted into the insertion hole 64d1 by inserting it from below and sliding it horizontally. Finally, by returning the bent portion 64d2 to its original position, the attachment of the first defrosting heater 50 to the first holding member 64 is completed.

[0047] Note that the shapes of the base end portions 51c1 and 53c1 of the caps 51 and 53, which are the main components for preventing the rotation of the defrosting heaters 50 and 52, are not limited to the above shapes. For example, as shown in FIG. 13, the base end portion 77 may be triangular so as to fill one corner of the insertion hole 71a. Also, for example, as shown in FIG. 14, the base end portion 78 may be an elongated strip extending radially toward the corner of the insertion hole 71a.

[0048] <Configuration within the second space> Next, the configuration within the second space S2 will be described. Since the second cooler 44 disposed within the second space S2 is for cooling the second storage chamber R3 which is a refrigerating chamber, its cooling capacity can be made smaller compared to the first cooler 42 that cools the first storage chamber R1 which is a freezer compartment. That is, the second cooler 44 can be of a smaller size compared to the first cooler 42, and as shown in FIG. 2, the width in the left - right direction is made smaller. Therefore, the width in the left - right direction of the second cooler chamber R4 is also made smaller compared to the first cooler chamber R2.

[0049] As shown in FIG. 2, within the second cooler chamber R4, together with the second cooler 44, a circulation fan 80 driven by a motor is accommodated. This circulation fan 80 is disposed adjacent to the air outlet 28B above the second cooler 44. During the cooling operation, due to the driving of the circulation fan 80, the air in the second storage chamber R3 is sucked from the air inlet 28A into the second cooler chamber R4, and then the cold air generated by heat exchange while passing through the second cooler 44 is blown out from the air outlet 28B into the second storage chamber R3. Thereby, the air within the second space S2 is circulated, and the configuration is such that the inside of the second storage chamber R3 is cooled.

[0050] Also, in order to melt the frost adhering to the second cooler 44, a third defrost heater 82 is accommodated in the second cooler chamber R4. As described above, in the cooling storage 10 of the present embodiment, since a flammable refrigerant is used for the refrigerant, it is necessary to consider the safety in the case where the flammable refrigerant leaks from the second cooler 44. The third defrost heater 82 is the same as the defrost heaters 50, 52 and is a longitudinal double - glass - tube heater, and its surface temperature is controlled to be equal to or lower than a temperature (set temperature) 100 K lower than the ignition temperature of the refrigerant. Further, in the third defrost heater 82, in order to avoid a situation where some abnormality occurs and the above - mentioned set temperature is greatly exceeded and overheats, a thermal fuse 84 same as the thermal fuse 54 accommodated in the first cooler chamber 42 is provided in the vicinity of the third defrost heater 82 (see FIGS. 15 - 17).

[0051] Moreover, the cooling refrigerator 10 of the present embodiment is characterized by the mounting structure of the fuse 84, which is an overheat detector, so that the fuse 84 operates properly. Hereinafter, the structure around the fuse 84 will be described in detail with reference to FIGS. 15 to 18.

[0052] In the cooling refrigerator 10 of the present embodiment, the third defrost heater 82 and the fuse 84 are housed in the second cooler chamber R4 in a state of being attached to the heater cover 90. The heater cover 90 holds the third defrost heater 82 at the caps 83 attached to both ends thereof. More specifically, the heater cover 90 is composed of a first cover member 90a and a second cover member 90b. The first cover member 90a has a side facing portion (heater facing portion) 91 that extends in the front-rear direction and faces the side (right side) of the third defrost heater 82, an upper facing portion (heater facing portion) 92 that faces above the third defrost heater 82, and a pair of holding portions 93 that are bent and formed from both ends of the side facing portion 91 in the front-rear direction. By engaging each of the pair of caps 83 of the third defrost heater 82 with each of the pair of holding portions 93, the third defrost heater 82 is held. Further, the second cover member 90b extends in the front-rear direction and covers the left side of the third defrost heater 82, and its main body portion 90b1 functions as a side facing portion (heater facing portion) that faces the side (left side) of the third defrost heater 82. Flange portions 94 and 90b2 that project outward (opposite to the third defrost heater 82) are formed on the pair of holding portions 93 of the first cover member 90a and the main body portion 90b1 of the second cover member 90b, respectively, and they are fastened to the partition wall 24 so as to be located directly below the second cooler 44 at these flange portions 94 and 90b2. Note that the upper facing portion 92 of the first cover member 90a is provided so that the defrost water of the second cooler 44 does not fall onto the third defrost heater 82, and is provided in a posture that slopes downward toward the right side (the side of the side facing portion 91). The defrost water that has fallen onto the upper facing portion 92 flows downward along the side facing portion 91.

[0053] Further, the first cover member 90a has an extension portion 96 that is continuously formed from the front end of the upper facing portion 92 and extends forward. The extension portion 96 has an extension portion main body 96a that is formed of the same plate surface as the upper facing portion 92, and a pedestal portion 96b that is formed by bending from the lower end (right end) of the extension portion main body 96a. It has a valley-shaped that tapers downward when viewed from the front. Along the connection portion between the extension portion main body 96a and the pedestal portion 96b, a fuse 84 is arranged and fixed to the upper surface side of the extension portion 96 by a clip 98.

[0054] In the cooling refrigerator 10 of the present embodiment, since the fuse 84 is provided outside the portion covering the third defrosting heater 82 by the heater cover 90, the infrared rays of the third defrosting heater 82 are not directly irradiated to the fuse 84. Therefore, when the third defrosting heater 82 is operating normally, the fuse 84 does not reach the operating temperature, and a situation where the fuse 84 malfunctions can be avoided. And the fuse 84 is provided for the extension portion 96 to which the radiant heat received by the upper facing portion 92, which is the heater facing portion, is transmitted, and it is possible to detect relatively early that the third defrosting heater 82 is in an overheated state. As described above, the cooling refrigerator 10 of the present embodiment uses a flammable refrigerant, and the surface temperature of the second defrosting heater 52 is set relatively low. However, since the fuse 84 can detect the heat conducted from the upper facing portion 92 to the extension portion 96, the overheated state of the third defrosting heater 82 can be appropriately detected, and the circuit interruption process can be performed at an appropriate timing.

[0055] The extension part 96 is shorter compared to the extension parts (the vertical wall part 66c1 and the pedestal part 75) corresponding to the second defrosting heater 52 described above. Although the fuse 84 attached to the extension part 96 is longitudinally long in the front-rear direction, the part (temperature sensing element) 84a that actually detects the ambient temperature is accommodated in the central part, and it is attached so that the part where the temperature sensing element 84a is accommodated overlaps with the extension part 96. Also, as described above, although the extension part main body 96a is formed on the same plate surface as the upper facing part 92, a holding part 93 is interposed between the extension part main body 96a and the heat generating surface (the part not covered by the cap 83) of the third defrosting heater 82. Therefore, infrared rays from the third defrosting heater 82 do not directly reach the extension part 96. Thus, the fuse 84 is not configured to detect an overheated state by the radiant heat during normal operation of the third defrosting heater 84, and it is surely activated only when the third defrosting heater 84 is abnormal.

[0056] Also, since the extension part 96 is a part that extends laterally from the upper facing part 92, compared to the extension part that extends upward (the vertical wall part 66c1) like the extension part corresponding to the second defrosting heater 52, radiant heat is less likely to be transmitted. Therefore, in this embodiment, the second cover member 90b is arranged to the left of the third defrosting heater 82, and as shown in FIG. 18, the upper end of the main body part 90b1 extends to the same height as the upper facing part 92. That is, the main body part 90b1 of the second cover member 90b receives radiant heat from the third defrosting heater 82, and the heat is radiated toward the lower surface of the upper facing part 92 facing the main body part 90b1. With such a configuration, the heat conductivity to the fuse 84 provided on the upper surface side of the extension part 96 in the first cover member 90a is enhanced, and the overheated state of the third defrosting heater 82 can be surely detected.

[0057] The fuse 84 is arranged above the cap 83 of the second defrost heater 82 outside the holding portion 93 of the heater cover 90 that covers the third defrost heater 82. That is, according to the above configuration, even in a space with a relatively small lateral width such as the second cooler chamber R4, the fuse 84 can be provided, and the fuse 84 can detect an abnormality of the third defrost heater 82 early and surely without being greatly affected by the radiant heat of the third defrost heater 82.

[0058] <<Embodiment 2>> Next, a refrigerated storage according to a second embodiment of the present invention will be described with reference to FIGS. 19 and 20. The refrigerated storage of the second embodiment has a configuration similar to that of the refrigerated storage 10 of the first embodiment, but the mounting structure of the second defrost heater 100 and the thermal fuse 102 to the second holding member 104 is different from that of the first embodiment.

[0059] The second defrosting heater 100 is held by the heater cover 110, but this heater cover 110 does not have an extension part as in the first embodiment. The heater cover 110 has a cover main body part 112 that extends in the front-rear direction and covers the right and lower sides of the second defrosting heater 100, and a pair of holding parts 113, 114 that are bent and formed from both ends of the cover main body part 112 in the front-rear direction. By engaging each of the two ends of the second defrosting heater 110 with each of the pair of holding parts 113, 114, the second defrosting heater 100 is held. Further, the heater cover 110 has a flange part 115 that extends so as to slope downward from the upper edge of the cover main body part 112, and at the flange part 115, it is fastened to the second holding member 104. Specifically, the second holding member 104 has an opening 104a formed therein that extends in the front-rear direction on the lower side of the circulation fan 48, and a roof part 104b that projects leftward from the upper edge of the opening 104a, similar to the first embodiment. The flange part 115 of the heater cover 110 is fastened to the lower surface side of this roof part 104b. The roof part 104b is longer than the flange part 115 and faces above the second defrosting heater 100, and also functions as a heater facing part that receives the radiant heat of the second defrosting heater 100.

[0060] The second holding member 104 has an inclined surface part 104d that slopes downward from the lower end of the plate part 104c where the opening 104a is formed, toward the left. The fuse 102 is fixed to the lower surface of this inclined surface part 104d by a clip 118. That is, in the second holding member 104, the radiant heat received by the roof part 104b is conducted to the inclined surface part 104d via the plate part 104c, and the fuse 102 is configured to detect at least the heat of this inclined surface part 104d. That is, the plate part 104c and the inclined surface part 104d function as extension parts that conduct radiant heat. Note that this inclined surface part 104d is arranged along the cover main body part 112 of the heater cover 110, and is made more likely to receive radiant heat from the cover main body part 112.

[0061] The cooling refrigerator of the present embodiment is suitable when it is impossible to secure space in the width direction (the left - right direction in FIG. 20) because the fuse 102 is located below the defrost heater 100.

[0062] ≪Other Embodiments≫ The present invention is not limited to the above - described embodiments, and can be implemented in various forms with various changes and improvements based on the knowledge of those skilled in the art. For example, the following embodiments are also included in the technical scope of the present invention.

[0063] The shape of the cover member having a heater - facing portion that faces the defrost heater and receives radiant heat from the defrost heater is not particularly limited. The shape of the extending portion is also not particularly limited, and it may extend in a direction away from the defrost heater in consideration of the space around the defrost heater. However, since heat easily travels upward, the extending portion can be made to extend upward to enhance heat conductivity.

[0064] In the above - described embodiment, the overheat detector is a fuse, but it may be a thermostat or a temperature sensor. However, as in the present embodiment, since the fuse cannot return even when the overheated state is released, it is desirable that the fuse be at a position where it can more accurately detect an abnormality of the defrost heater without being affected by the radiant heat of the defrost heater, and the cooling refrigerator of the present invention is suitable.

[0065] The fuse has a determined operating temperature (cutting off the circuit), but the cooling refrigerator of the present invention can adjust the temperature of the heat transmitted according to the length of the extending portion and can also adjust the distance from the defrost heater (the influence of radiant heat). Therefore, it is possible to easily arrange the fuse at an appropriate position according to the operating temperature of the fuse. Also, when the capacity of the heater is changed, the position of the fuse can be easily changed according to the heater.

[0066] In addition, the following configuration can be exemplified as a configuration for dealing with cases where the operating temperature of the fuse is changed or the capacity of the heater is changed during the design stage. An opening is provided near the extending portion in the extending portion or the heater facing portion where heat is conducted, and a configuration is adopted in which the state of closing the opening with a sheet metal and the state of not closing it can be selectively realized. That is, by selectively realizing the state in which the heat conduction is facilitated by closing the opening with the sheet metal and the state in which the heat conduction portion is reduced by removing the sheet metal, it is possible to easily cope with the above-mentioned changes and differences in specifications.

[0067] The present invention is not limited to a horizontal refrigerator, and of course it can be adopted in a freezer, and can also be adopted in a vertical refrigerator-freezer. Furthermore, it can also be adopted in a refrigerated freezer showcase or a prefabricated refrigerator-freezer.

Description of Reference Numerals

[0068] 10… Cooling storage cabinet, R1… First storage chamber, R3… Second storage chamber, 34… Cooling device, 42… First cooler, 44… Second cooler, 48… Circulation fan, 52… Second defrost heater, 54… Thermal fuse [overheat detector], 66… Second holding member [second cover member, holding member], 66c1… Standing wall portion [extending portion], 66e… Roof portion [heater facing portion, upper facing portion], 68… Heater cover [first cover member], 70… Cover main body portion [heater facing portion, side facing portion], 71… Holding portion, 72… Holding portion, 73… Mounting portion [upper extending portion], 75… Pedestal portion, 80… Circulation fan, 82… Third defrost heater, 84… Thermal fuse [overheat detector], 90… Heater cover [cover member], 92… Upper facing portion [heater facing portion], 93… Pair of holding portions, 96… Extending portion, 100… Second defrost heater, 102… Fuse [overheat detector], 104… Second holding member [cover member], 104b… Roof portion [heater facing portion], 104c… Plate portion [extending portion], 104d… Inclined surface portion [extending portion]

Claims

1. A storage room, a cooler for cooling the air flowing into the storage room, a defrosting heater for melting the frost generated by the cooler, an overheat detector capable of detecting ambient heat to prevent overheating by the defrosting heater, a cover member covering at least a part of the defrosting heater, comprising: The cover member has a heater facing portion facing the defrosting heater and receiving radiant heat from the defrosting heater, and an extending portion which is a portion continuously formed from the heater facing portion and extends outward of the space covering the defrosting heater, having: The overheat detector is fixed to the extending portion and detects heat conducted from the heater facing portion to the extending portion. A refrigerated storage characterized by this.

2. Including the cooler, comprising a refrigeration cycle type cooling device in which a flammable refrigerant circulates, The defrosting heater has a surface temperature equal to or lower than a temperature set lower than the ignition temperature of the flammable refrigerant. The refrigerated storage according to claim 1.

3. The heater facing portion is supposed to be erected so as to cover the side of the defrosting heater, The extending portion has a pedestal portion extending from the heater facing portion toward the side opposite to the defrosting heater. The overheat detector is fixed to the pedestal portion. The refrigerated storage according to claim 1 or claim 2.

4. A first cover member which is the cover member covering the side of the defrosting heater, and a second cover member which is the cover member covering the upper part of the defrosting heater, In the first cover member, the heater facing portion is a side facing portion facing the side of the defrosting heater, the extending portion is an upward extending portion extending upward from the side facing portion, and a pedestal portion extending from the upper end of the upward extending portion toward the side opposite to the defrosting heater. In the second cover member, the heater facing portion is an upper facing portion facing the upper part of the defrosting heater, and the extending portion is a standing wall portion standing upward from the edge on the side of the side facing portion in the upper facing portion. The upward extending portion of the first cover member and the standing wall portion of the second cover member are overlapped. The overheat detector is fixed along the corner formed by the standing wall portion and the pedestal portion, and detects heat from both the standing wall portion and the pedestal portion. The refrigerated storage according to claim 1 or claim 2.

5. A circulation fan that circulates air between the cooler and the storage chamber, and a holding member that holds the circulation fan. The holding member is configured to hold the defrost heater below the circulation fan, and has a roof portion that is formed to project between the circulation fan and the defrost heater and receives defrost water from the circulation fan. The roof portion functions as the upper facing portion, and the holding member functions as the second cover member. The cooling storage according to claim 4.

6. The defrost heater is in a longitudinal shape. The cover member has a pair of holding portions that hold the defrost heater at both end portions in the longitudinal direction, and has an upper facing portion that faces above the defrost heater as the heater facing portion. The extending portion extends outward from the holding portion from one end in the longitudinal direction of the upper facing portion. The overheat detector is fixed to the upper surface side of the extending portion. The cooling storage according to claim 1 or claim 2.

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