Unit cooler and cleaning unit

Abstract

To provide a unit cooler and a cleaning unit capable of changing a direction of cold air blown out from the unit cooler and preventing drain water generated in defrosting operation from dripping from the unit cooler into a storage.SOLUTION: A unit cooler 4 has: an evaporator 41; a cooling fan 42 that blows air to the evaporator; a housing 40 that comprises a suction port 40a that draws in air when the cooling fan is operating, and a blowout port 40b that blows out air when the cooling fan is operating; a blowout member 100 that comprises a fan guard 100b having a plurality of ventilation holes 100a, a louver 101 for changing a wind direction, and a defrosting heater 47, and that is provided downstream of the blowout port; and a drainage channel that guides drain water generated in the blowout member by heat generated by the defrosting heater to the housing. The louver is provided in the blowout member, and is located between the fan guard and the cooling fan.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE The present invention relates to a unit cooler and a cooling unit. [Background technology]

[0002] There is known a unit cooler that is installed inside a storage facility and that is connected to a refrigerator installed outside the storage facility via a connecting pipe to form a refrigeration cycle circuit and that cools the inside of the storage facility to, for example, -30°C to -5°C. The unit cooler includes an evaporator that constitutes the refrigeration cycle circuit. When the cooling unit is operated, water vapor contained in the air inside the storage facility gradually turns to frost and adheres to the evaporator. This reduces the heat exchange efficiency of the evaporator, and the inside of the storage facility cannot be sufficiently cooled. Therefore, a defrosting operation is performed as appropriate to melt and remove the frost that has adhered to the evaporator by using heat from a defrost heater. When such a unit cooler is installed on the ceiling of a long and narrow storage facility, it is difficult to deliver the air blown out to the opposite side of the unit cooler. In addition, the air blown out from the unit cooler may short-circuit.

[0003] Therefore, in Patent Document 1, an air guide plate that protrudes forward from the lower end of the air outlet of a unit cooler installed on the ceiling surface of a storage facility is provided. In such a unit cooler, air is blown upward from the air outlet, so that cool air can be distributed throughout the storage facility. However, because the air guide plate protrudes far into the storage facility from the main body of the unit cooler, there is a problem that water condensed on the outer wall, i.e., the surface of the air guide plate facing the storage facility, turns into frost, which is further cooled and freezes, causing the ice to grow large. Also, as in Patent Document 2, in an outdoor unit of an air conditioner having a heat exchanger and a fan inside, for safety, a lattice-shaped fan guard is provided at the outlet so that the user's fingers do not touch the rotating fan, and furthermore, a so-called louver is provided on the downstream side in front of the fan guard to change the air direction to upward or downward. Since such an outdoor unit of an air conditioner is installed outdoors, the vicinity of the outlet generally does not freeze, and even if the vicinity of the outlet freezes, the drain water generated by melting ice falls outside, so there is no problem with drainage. In contrast, in a unit cooler installed at a high position in a storage facility, frost due to condensation water and dripping of drain water generated by melting ice may damage the stored goods stored in the storage facility, and the treatment of this water is an important issue in terms of its marketability. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-257826 [Patent Document 2] Japanese Patent Application Publication No. 9-329346 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem that the present invention aims to solve is to provide a unit cooler and a cooling unit that can change the direction of cold air blown out from the unit cooler and prevent drain water generated during defrosting operation from dripping from the unit cooler into a storage facility. [Means for solving the problem]

[0006] The unit cooler of the embodiment has a housing including an evaporator, a cooling fan that blows air to the evaporator, an inlet that draws in air by operating the cooling fan, and an outlet that blows out air by operating the cooling fan, a fan guard with multiple ventilation holes, a louver that changes the air direction, a defrost heater, and an outlet member provided downstream of the outlet, and a drainage channel that guides drain water generated in the outlet member by heat generated by the defrost heater to the housing. The louver is provided in the outlet member and is located between the fan guard and the cooling fan. In addition, in another embodiment, a cooling unit including the above-mentioned unit cooler is disclosed. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic diagram of a storage cooling system using the unit cooler of this embodiment. [Diagram 2] FIG. 2 is a perspective view showing a cross section of the unit cooler in the embodiment. [Diagram 3] FIG. 4 is an enlarged cross-sectional view of a blowing portion of the unit cooler in the embodiment. [Figure 4] 3 is a cross-sectional view of the fan guard in this embodiment taken along the line FF in FIG. 2. [Diagram 5] FIG. 2 is a block diagram relating to control of the storage cooling system of the present embodiment. [Figure 6] 4 is a control flowchart of the unit cooler in the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, this embodiment will be described with reference to FIGS.

[0009] (Overall composition) In FIG. 1, the storage facility cooling system 1 includes a storage facility 2 in which stored items A to C, such as food, are stored, and a cooling unit 10.

[0010] The storage facility 2 is a room that serves as a freezer / refrigerator, and its walls are composed of an outer shell 2a, a heat insulating material 2b, and an inner shell 2c, and the outer shell 2a and the inner shell 2c are formed of metal plates such as stainless steel. The storage facility 2 has a sandwich structure in which the heat insulating material 2b, which is made of a foam material or the like, is sandwiched between the outer shell 2a and the inner shell 2c.

[0011] A door 3 is provided in part of this storage facility 2, and a user can enter and exit the storage facility 2 through this door 3 to bring stored items A to C into the storage facility 2 and take out cooled stored items A to C.

[0012] The cooling unit 10 is composed of a unit cooler 4 installed inside the storage facility 2 and equipped with an evaporator 41, a refrigerator 5 (condensing unit) which is generally installed outdoors outside the storage facility 2 and equipped with a compressor 51 and a condenser 52, and connecting piping 6 connecting these.

[0013] (Unit cooler) Next, the structure of the unit cooler 4 of this embodiment will be described.

[0014] The unit cooler 4 has a horizontally long box-like housing 40 formed of sheet metal that serves as the outer shell thereof.

[0015] The housing 40 is hung from the ceiling surface 2d, which is the ceiling of the storage facility 2, by a hanging device 21. Openings are formed on both sides of the housing 40, which serve as an inlet 40a and an outlet 40b. The housing 40 accommodates the inlet 40a, the evaporator 41, the cooling fan 42, and the outlet 40b, arranged in this order from one end (the right side in FIG. 1) to the other end (the left side in FIG. 1). The housing 40 further includes a bottom plate 43, which is located below the evaporator 41 and the cooling fan 42 and forms the bottom surface thereof.

[0016] The opening of the suction port 40a may have any shape, but since the evaporator 41 has a rectangular shape when viewed from the air inflow direction, it is preferable that the opening have the same rectangular shape as the evaporator 41.

[0017] The evaporator 41 is a so-called fin-and-tube heat exchanger having a horizontally elongated rectangular parallelepiped shape and made up of a serpentine copper pipe 41p through which a refrigerant flows and a plurality of aluminum fins 41f through which the copper pipe 41p penetrates (see FIG. 2).

[0018] Cooling fan 42, which is rotated by fan motor 42m, is a metallic propeller fan that can withstand high temperatures during defrosting operation, and draws in air from storage 2 through intake port 40a provided at one end of housing 40. The air drawn in through intake port 40a passes through evaporator 41 and is blown out into storage 2 through outlet port 40b provided at the other end of housing 40. This air flow is indicated by dashed arrows in Figure 1. Any number of cooling fans 42 may be installed, and if unit cooler 4 has a large capacity, two or more may be arranged side by side.

[0019] An internal temperature sensor 48 for detecting the air temperature inside the storage facility 2 is provided near the intake port 40a through which the wind generated by the operation of the cooling fan 42 passes.

[0020] The opening of air outlet 40b may have any shape, but because cooling fan 42 has a circular shape when viewed from the air inflow direction, it is preferable that the opening be a circle with a diameter slightly larger than that of cooling fan 42. Air outlet 40b is also generally called a fan guard or a bell mouth.

[0021] As shown in FIG. 2, the unit cooler 4 is provided with a blowing member 100 so as to cover the blowing port 40b of the housing 40.

[0022] The blowing member 100 is a box body integrally molded from sheet metal like the housing 40, and one side is open. The open side is connected to the blowing outlet 40b of the housing 40, and the blowing member 100 covers the blowing outlet 40b. The side opposite the open side is closed by a fan guard 100b having a plurality of ventilation holes 100a. That is, when the fan guard 100b is the bottom side, the blowing member 100 forms a box body having an edge portion 100c extending vertically upward from the outer edge of the fan guard 100b, that is, four sides, the top and bottom sides and both side sides at the position of the blowing member 100 shown in FIG. 1. The corners of each edge portion 100c are fixed to each other by spot welding or screws.

[0023] On the upstream side of the fan guard 100b in the blowing member 100, that is, on the cooling fan 42 side, a plurality of louvers 101 for changing the air direction are provided. Each louver 101 is made of sheet metal like the housing 40 and the blowing member 100, and has a rectangular shape extending in the horizontal direction. The multiple louvers 101 are arranged at equal intervals in the vertical direction between the fan guard 100b and the cooling fan 42, and both ends and the center of the part bent to fit the surface of the fan guard 100b are fixed to the fan guard 100b by fastening members 102 such as screws (see FIGS. 3 and 4). At this time, the fastening members 102 such as screws may be inserted from either the upstream side or the downstream side of the fan guard 100b. The number and shape of the louvers 101 may be changed as appropriate depending on the capacity of the unit cooler 4.

[0024] Each louver 101 has an inverted V-shape on the side, and is attached at an incline so that the other end of the long side that is not fixed is located lower than the other end of the short side that is fixed to the fan guard 100b. That is, the louvers 101 are installed so that the direction of the air blown out from the unit cooler 4 is upward. As a result, the air blown out from the air outlet 40b of the housing 40 by the cooling fan 42 flows along the inclined louvers 101 and is blown out upward into the storage 2 from the ventilation holes 100a of the fan guard 100b. This air flow is indicated by dashed arrows in FIG. 2.

[0025] As shown in Figs. 2 to 4, the defrost heater 47 is attached to the inner peripheral surface of the blowing member 100, specifically, the sheet metal of the fan guard 100b, on the upstream side of the fan guard 100b in a manner surrounding the outer periphery of the fan guard 100b in close contact with the inner peripheral surface of the blowing member 100, specifically, the sheet metal of the fan guard 100b. During a defrosting operation described later, the defrost heater 47 generates heat, and the heat is transferred from the outer periphery of the fan guard 100b to the entire fan guard 100b and the edge portion 100c. The defrost heater 47 is provided in places where condensed water is likely to freeze, such as around the evaporator 41 and the bottom plate 43 of the housing 40, in addition to the blowing member 100 (see Fig. 2). The defrost heater 47 may be attached to the inner peripheral surface of the upper and lower side surfaces of the blowing member 100, as long as the heat is smoothly transferred to the sheet metal of the fan guard 100b.

[0026] Bottom plate 43, which is made of sheet metal and forms the bottom surface of housing 40, is formed separately from the ceiling plate and both side plates of housing 40. Bottom plate 43 serves as a drain pan that receives drain water generated in evaporator 41. Bottom plate 43 can be opened and closed relative to housing 40, and is attached and fixed to the side of housing 40 by a hinge structure. This allows the user to open bottom plate 43 and clean off dirt such as dust that has accumulated on its upper surface as drain water flows or accumulates.

[0027] A drain outlet 43a is provided in the bottom plate 43, and the bottom plate 43 is gently inclined so as to gradually descend toward the drain outlet 43a (see FIG. 1). In this embodiment, the drain outlet 43a is provided in the center of the bottom plate 43, but the drain outlet 43a may be provided anywhere on the bottom plate 43 as long as the bottom plate 43 is arranged to gently slope downward toward the drain outlet 43a.

[0028] One end of a drain pipe 44 made of flexible synthetic resin is connected to the drain outlet 43a when the unit cooler 4 is installed. The other end is extended outside the storage facility 2 and drains the drain water collected on the bottom plate 43 out of the storage facility 2.

[0029] The joint between the blowing member 100 and the blowing outlet 40b will be described with reference to FIG.

[0030] The edge portions 100c forming the four sides of the blowing member 100 described above have flange portions 100d bent outward at their ends. The flange portions 100d of the blowing member 100 are fastened and fixed to the peripheral portion of the blowing outlet 40b (the housing 40) by fastening members 103 such as screws. Therefore, the opening of the blowing member 100 is formed to be slightly smaller than the surface of the blowing outlet 40b and large enough to completely cover the opening of the blowing outlet 40b. When the flange portions 100d are fixed to the housing 40, a minute gap D is provided in the fixing portion where the flange portions 100d and the outer wall of the housing 40 overlap in the horizontal direction.

[0031] Then, the bottom plate 43 is fastened and fixed to the housing 40, more specifically, to the peripheral portion of the air outlet 40b, by using fastening members 49 such as screws so as to cover the flange portion 100d of the air outlet member 100 from below. At this time, a gap M is provided in the fixed portion where the bottom plate 43 and the outer wall of the housing 40 overlap. The gap M is larger than the above-mentioned gap D. That is, the bottom plate 43 is fastened and fixed so as to sandwich the flange portion 100d between the bottom plate 43 and the housing 40. Since the gap M becomes a passage that communicates the upstream side and the downstream side of the cooling fan 42, it is desirable to make the dimension as small as possible so that the air blown by the cooling fan 42 does not short-circuit through this passage. A drainage channel 104 is formed from the air outlet 40b to the bottom plate 43 by both the above-mentioned gap D and gap M. The drainage channel 104 will be described in detail later.

[0032] 3, the blowing member 100, the housing 40, and the bottom plate 43 are arranged and fastened in the order of the housing 40, the blowing member 100, and the bottom plate 43 from the upstream side of the cooling fan 42. However, regardless of this arrangement of the three components described above, it is sufficient that the gap D of the fixed portion where the flange portion 100d of the blowing member 100 and the housing 40 overlap is located above the bottom plate 43.

[0033] 3, the flange portion 100d of the blowing member 100 is fastened to the housing 40, and the bottom plate 43 is fastened to the housing 40, but the flange portion 100d of the blowing member 100 may be fastened to the bottom plate 43, or the bottom plate 43 may be fastened to the housing 40. As described above, as long as the gap D of the fixing portion where the flange portion 100d of the blowing member 100 and the housing 40 overlap is located above the bottom plate 43, any of the components may be fastened to each other. At this time, the fastening members 103 and 49 such as screws may be inserted from either the upstream side or the downstream side of the cooling fan 42.

[0034] (Refrigeration machine) 1, the chiller 5 connected to the unit cooler 4 by a connecting pipe 6 has an outer casing 50. The chiller 5 is generally installed outdoors.

[0035] The housing 50 contains a compressor 51 that compresses the refrigerant, a condenser 52 that exchanges heat between the refrigerant and outdoor air, usually outside air, a condenser fan 53, and a refrigeration unit controller 54 that receives instructions from the controller 7, which will be described later.

[0036] The refrigerator 5 is provided with a connection part to which one end of the connection pipe 6 is connected. The connection part is composed of a liquid side connection part 61a to which one end of the liquid side connection pipe 6a is connected, and a gas side refrigerator connection part 61b to which one end of the gas side connection pipe 6b is connected. The liquid side connection part 61a is connected to the condenser 52 via a refrigerant pipe 8b in the refrigerator 5, and the gas side refrigerator connection part 61b is connected to the compressor 51 via the refrigerant pipe 8b. The compressor 51 and the condenser 52 are connected by the refrigerant pipe 8b.

[0037] (Refrigeration cycle) The cooling unit 10 has a refrigeration cycle circuit 11 formed by connecting a unit cooler 4 and a refrigerator 5 with a connecting pipe 6. The compressor 51 operates with the operation of the cooling unit 10, and a refrigerant flows in the refrigeration cycle circuit 11 as shown by the solid arrow in Fig. 1. The refrigerants flowing in the refrigeration cycle circuit 11 include R404A, R410A, R448A, and R449A.

[0038] The refrigerant that has entered the housing 50 of the refrigerator 5 from the gas side refrigerator connection part 61b is sucked into the compressor 51, compressed by the compressor 51, and then discharged from the compressor 51 as a high-temperature, high-pressure gas refrigerant. The gas refrigerant discharged from the compressor 51 flows into the condenser 52 through the refrigerant piping 8b, and is condensed in the condenser 52 by releasing heat to the outside air due to the blowing of the condenser fan 53. The refrigerant condensed in the condenser 52 flows out of the condenser 52 as a low-temperature, high-pressure liquid refrigerant, and flows into the unit cooler 4 from the liquid side connection part 60a of the unit cooler 4 via the liquid side connection piping 6a.

[0039] The liquid refrigerant that flows into the unit cooler 4 passes through an on-off valve 45, is decompressed by an expansion valve 46 to a low temperature, and flows into the evaporator 41. The liquid refrigerant that flows into the evaporator 41 exchanges heat with the air in the storage tank 2 and evaporates as a result of operation of the cooling fan 42. The expansion valve 46 is a thermostatic expansion valve equipped with a temperature-sensing bulb, or an electronic expansion valve whose valve opening can be electrically adjusted.

[0040] The refrigerant evaporated in the evaporator 41 flows out of the evaporator 41 as a low-temperature, low-pressure gas refrigerant, returns to the refrigerator 5 from the gas side connection part 60b via the gas side connection pipe 6b, and is sucked again into the compressor 51 via the gas side refrigerator connection part 61b. By circulating the refrigerant in the refrigeration cycle circuit 11 in this manner, the air in the storage facility 2 is cooled by the evaporator 41.

[0041] (Control of cooling unit 10) Next, the control circuit will be described. As shown in Fig. 5, a controller 7 for controlling the unit cooler 4 and the refrigerator 5 is provided as a control means for the cooling unit 10.

[0042] The controller 7 has a housing made of sheet metal or the like. The controller 7 uses a single-phase commercial alternating current power supply AC as its operating power supply, and performs overall control of the unit cooler 4 and the refrigerator 5. The controller 7 is installed in the outer shell 2a of the storehouse 2 or the like. In particular, the controller 7 is often attached to the outer wall (outer shell 2a) near the door 3 of the storehouse 2 so that it is easy for a user to operate. The alternating current power supply AC is supplied to the controller 7 via a power supply terminal block 91. At this time, the alternating current power supply AC is not limited to a single-phase power supply, and a three-phase power supply may also be used.

[0043] A refrigerator controller 54 housed in the refrigerator 5 uses the same commercial AC power supply as the controller 7 as its operating power source, and controls the operation of the compressor 51 and the condenser fan 53 in the refrigerator 5 in response to commands from the controller 7.

[0044] 5, the controller 7 includes a controller control unit 71, a communication unit 72, an operation display unit 73, and a relay group 74. The refrigerator control unit 54 and the controller control unit 71 each include a microcomputer (MCU) and its peripheral circuits, and operate based on a program stored in an internal memory. Each of the controllers 54 and 71 can also be formed by a logic circuit.

[0045] The controller 71 operates as the center of control for each device, and is connected to the inside temperature sensor 48 of the storage facility 2 via a communication unit 72, an operation display unit 73, a relay group 74, and wiring. The unit cooler 4 and the controller 7 are also connected by a crossover wire 75 that penetrates the wall of the storage facility 2 via a controller terminal block 92 and a housing terminal block 93.

[0046] The housing terminal block 93 is provided inside the housing 40 of the unit cooler 4, or inside an electric component box provided on the outer wall of the housing 40. This housing terminal block 93 is provided with a terminal block heater that is constantly energized to prevent condensation and freezing.

[0047] The communication unit 72 is connected to the refrigerator controller 54 of the refrigerator 5 through a communication line 76 via a communication terminal block 94. The communication unit 72 transmits and receives instructions and data between the controller 71 and the refrigerator controller 54 of the refrigerator 5.

[0048] The operation and display section 73 includes an operation section 73a that allows the user to operate the cooling unit 10 on / off and to operate the set temperature, and a display section 73b that displays the internal temperature of the storage facility 2 and the operating status.

[0049] Inside the controller 7, the relays 74a to 74c of the relay group 74 are turned ON (energized) or OFF (deenergized) in response to an output signal from the controller 71. The relays 74a to 74c each have an open / close contact, and one end of each of the relays 74a to 74c is commonly connected to one end of the alternating current power supply AC. The other end of the AC power supply AC passes through the inside of the controller 7 without passing through a switch such as a relay, and is connected to a controller terminal block 92 provided in the controller 7 and a housing terminal block 93 provided in the unit cooler 4 via a jumper wire 75.

[0050] The relay 74 a corresponds to the defrost heater 47 , the relay 74 b corresponds to the fan motor 42 m that drives the cooling fan 42 , and the relay 74 c corresponds to the on-off valve 45 .

[0051] The controller 71 controls the ON / OFF of each of the relays 74a to 74c, thereby controlling the ON / OFF of each device connected to the relay. That is, the defrost heater 47 is an electric heating wire, such as a cord heater, that is energized and generates heat when the relay 74a is turned ON, and the fan motor 42m is an induction motor (motor) that is energized and rotates when the relay 74b is turned ON. Furthermore, the opening / closing valve 45 that is closed during the defrosting operation is provided with an actuator that opens when energized and closes when not energized, and opens when the relay 74c is turned ON and closes when it is turned OFF.

[0052] The internal temperature sensor 48 is a temperature sensing element such as a thermistor that detects the temperature of the intake air near the intake port 40a of the unit cooler 4, and is connected to the controller 71 via the housing terminal block 93, the crossover wire 75, and the controller terminal block 92, and inputs a voltage value converted as the internal temperature of the storage facility 2 to the controller 71. The internal temperature sensor 48 may be provided at an appropriate location in the storage facility 2, independent of the housing 40 of the unit cooler 4.

[0053] The control operation executed by the controller 71 of the controller 7 will be described with reference to the flow chart of FIG.

[0054] When the operation start (ON) is operated via the operation display unit 73, the controller 7 resets the cooling operation time timer E1 built into the controller control device 71, restarts this timer E1, and begins accumulating the cooling operation time t1 (S1).

[0055] Next, if the internal temperature Ta detected by the internal temperature sensor 48 is equal to or higher than the set internal temperature Ts (YES in S2), cooling inside the storage facility 2 is necessary, so the thermo-on state is entered and the controller 7 sends an ON signal to the refrigerator 5 and turns ON the cooling fan 42 and the opening / closing valve 45 of the unit cooler 4 to start or continue the cooling operation (S3).

[0056] If the internal temperature Ta detected by the internal temperature sensor 48 is lower than the set internal temperature Ts (NO in S2), the thermo-off state is established, the controller 7 does not send ON to the refrigerator 5, and the cooling operation is stopped or not started (S10). Steps S10 and S2 are repeated until the internal temperature Ta becomes equal to or higher than the set internal temperature Ts (YES in S2).

[0057] When the cooling operation time t1, which is the time counted by the cooling operation timer E1 during the cooling operation in step S3, reaches a preset time ts1 (YES in S4), the controller 7 turns off the relay 74c by the controller control device 71. This closes the on-off valve 45 of the unit cooler 4, and starts pump-down, which is a defrost preparation operation. In addition, the controller control device 71 starts the pump-down time timer E2, and starts integrating the pump-down time t2 (S5). This pump-down operation causes the refrigerant in the unit cooler 4 to be sucked out to the refrigerator 5 side, and there is almost no refrigerant in the refrigerant pipe 8a and the evaporator 41 in the unit cooler 4, so that the defrost operation can be safely performed. The set time ts1 is the cooling operation time when it is assumed that the defrost operation will be required, and is, for example, 8 hours.

[0058] On the other hand, if the cooling operation time t1 has not reached the set time ts1 (NO in S4), the pump-down, which is the defrost preparation operation, is not started and the cooling operation is continued (return from S4 to S2).

[0059] When the pump-down time t2, which is the time counted by the pump-down time timer E2, reaches the set pump-down time ts2 (YES in S6), the controller 7 transmits a signal from the controller control unit 71 to the communication unit 72, and communicates with the refrigerator control unit 54 of the refrigerator 5 to turn off the refrigerator 5. In addition, by turning off the relay 54b, the cooling fan 42 of the unit cooler 4 is turned off. Furthermore, by turning on the relay 54a, the defrost heater 47 is energized to start the defrost operation. At this time, the defrost timer E3 is started to start accumulating the defrost operation time t3. In addition, the pump-down time timer E2 of the controller control unit 71 is reset to end the accumulation of the pump-down time t2 (S7). Here, the pump-down time ts2 is set to the time required to suck the refrigerant in the unit cooler 4 to the refrigerator 5 side, and is, for example, about 5 minutes.

[0060] When the defrost operation time t3, which is the time counted by the defrost timer E3, reaches a preset defrost operation time ts3 (YES in S8), the controller 7 turns off the relay 54a to turn off the defrost heater 47 and terminate the defrost operation. At this time, the defrost timer E3 is reset and the accumulation of the defrost operation time t3 is terminated (S9). Then, preparations are made to return to the cooling operation again. The defrost operation time t3 is set as the time until the defrost water, which has melted the ice in each part in the unit cooler 4, is drained from the bottom plate 43, and is usually selected to be about 30 minutes. At this time, the end of the defrost operation time t3 may be set as the time when the temperature detected by the temperature sensor provided in the evaporator 41 reaches a predetermined temperature, for example, about 15 degrees, or when a predetermined time, for example, about 5 minutes, has elapsed after the temperature reaches the predetermined temperature.

[0061] Thereafter, the operation returns to the cooling operation (S1) unless the operation is turned off by operating the controller operation display unit 73, and this is repeated.

[0062] The above-mentioned steps are repeated, and the cooling operation and the defrosting operation of the cooling unit 10 are repeatedly performed. During cooling operation (when S3 in FIG. 6 is being executed), the low-humidity cooled air blown out from air outlet 40b is guided along upward louvers 101 toward ceiling surface 2d of storehouse 2, and sublimates ice that has grown from frost caused by condensation and adhered to ceiling surface 2d. The sublimated ice becomes gas and disperses within storehouse 2. This makes it possible to prevent the growth of ice that has adhered to ceiling surface 2d in the direction of air outlet 40b.

[0063] Furthermore, the cooled air blown out from the air outlet 40b collides with the ceiling surface 2d of the storage facility 2 once and is dispersed throughout the storage facility 2, so that the cooled air reaches throughout the storage facility 2 and efficiently cools the stored items A to C stored within the storage facility 2.

[0064] During defrosting operation (during execution of S7 in FIG. 6), frost and ice attached to the blowing member 100 and the louver 101 are melted by heat generated by the defrost heater 47, and drip as drain water. As shown by the dashed arrow in FIG. 3, the drain water drips downward inside the blowing member 100 along the surface of the louver 101. The drain water that has flowed along the surface of the louver 101 accumulates at the edge portion 100c that is the inner lower surface of the blowing member 100, and then flows downward from the gap D formed between the flange portion 100d of the blowing member 100 and the housing 40, and further passes through the gap M formed between the bottom plate 43 and the housing 40 and flows down onto the bottom plate 43. In this way, the drainage channel 104 formed by the gap D and the gap M allows the drain water in the blowing member 100 to be guided to the bottom plate 43 of the housing 40 that serves as a drain pan, and collected in the bottom plate 43. The drain water collected on the bottom plate 43 is drained outside the storage facility 2 from the drain pipe 44 connected to the drain outlet 43a of the bottom plate 43 together with frost and ice on the evaporator 41 melted by the defrost heater 47 provided in a part other than the blowing member 100 and drain water such as ice accumulated on the bottom plate 43, so there is no risk of the drain water dripping from the blowing member 100 or the housing 40 into the storage facility 2. In this case, the edge portion 100c may be inclined gradually downward toward the blowing port 40b so that the drain water accumulated at the edge portion 100c can easily flow down from the edge portion 100c into the gap D formed between the flange portion 100d of the blowing member 100 and the housing 40.

[0065] Furthermore, by providing the louvers 101 between the fan guard 100b and the cooling fan 42, if a user accidentally inserts his / her hand or the like through the ventilation hole 100a, the louvers 101 in addition to the fan guard 100b become an obstacle, preventing the user's hand from coming into contact with the cooling fan 42.

[0066] Since the louver 101 protects the cooling fan 42 from foreign objects in the same manner as the fan guard 100b, the hole size of the ventilation holes 100a of the fan guard 100b may be increased. This allows air to easily pass through the ventilation holes 100a, and the stored items A to C stored in the storehouse 2 can be efficiently cooled. In addition, the material used for the fan guard 100b can be reduced. In this case, the fan guard 100b may be made of punched metal as shown in Figs. 2 and 4, or may be configured by arranging a plurality of elongated rod-shaped members in a lattice pattern at the blow-out opening. The number and shape of the ventilation holes 100a may be appropriately changed depending on the air volume of the cooling fan 42 and the area of ​​the storehouse 2.

[0067] Although one embodiment of the present invention has been described, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0068] 4...Unit cooler 5…Freezer 6…Connecting piping 7. Controller 10…Cooling unit 40…Housing 41...Evaporator 42…Cooling fan 43…Bottom plate 44…Drain pipe 47…Defrost heater 49, 102, 103...Fastening members 100...Blow-out member 100a…Ventilation hole 100b…Fan guard 100c…Edge 100d…Flange section 101…Louver D, M: Gap 104...Drainage channel

Claims

1. a housing that houses an evaporator and a cooling fan and has an intake port through which air is drawn by operation of the cooling fan and an outlet port through which air is blown out by operation of the cooling fan; a blowing member provided on a downstream side of the air outlet of the housing and including a fan guard having a plurality of ventilation holes; a louver provided between the fan guard and the cooling fan in the blowing member to change the direction of airflow; A defrost heater that heats the blowing member; a drainage channel for guiding drain water generated in the blowing member by heat generated by the defrost heater to the housing.

2. The unit cooler according to claim 1, characterized in that the louvers are fixed to the inside of the fan guard and are inclined so that the other end that is not fixed to the fan guard is positioned lower than the other end that is fixed to the fan guard.

3. the housing includes a bottom plate located below the evaporator and the cooling fan, The unit cooler according to claim 1, wherein the drainage channel is provided between the blowing member and the blowing outlet, and between the bottom plate and the blowing outlet.

4. 4. The unit cooler according to claim 3, wherein the drainage channel is located above the bottom plate.

5. The housing is located below the evaporator and the cooling fan and includes a bottom plate that receives the drain water generated in the blowing member by heat generated by the defrost heater, The blowing member has an end portion fixed to the downstream side of the blowing port with a gap therebetween, and the bottom plate has an end portion fixed to the downstream side of the blowing port with a gap therebetween, 2. The unit cooler according to claim 1, wherein the end of the blowing member is located upstream of the blowing port relative to the end of the bottom plate.

6. 2. The unit cooler according to claim 1, wherein the fan guard is made of a punching metal.

7. a housing that is installed in a storage facility in which stored items are stored, houses an evaporator and a cooling fan, and includes an intake port that draws in air by operating the cooling fan, an outlet port that blows out air by operating the cooling fan, and a bottom plate that is located below the evaporator and the cooling fan; a blowing member provided on a downstream side of the air outlet of the housing and including a fan guard having a plurality of ventilation holes; a louver fixed to the inside of the fan guard and inclined so that one end not fixed to the fan guard is positioned lower than the other end fixed to the fan guard; A defrost heater that heats the blowing member; a drainage channel for guiding drain water generated in the blowing member by heat generated by the defrost heater to the bottom plate; A unit cooler characterized by comprising: a drain outlet provided in the bottom plate for connecting a drain pipe for discharging drain water collected in the bottom plate outside the storage facility.

8. 7. The unit cooler according to claim 3, wherein the bottom plate is provided with a drain outlet for connecting a drain pipe for discharging the drain water outside the storage facility.

9. 8. A cooling unit comprising: the unit cooler according to claim 1; a refrigerator having a compressor for compressing a refrigerant and a condenser for exchanging heat between the refrigerant and outside air; and a connecting pipe connecting the unit cooler and the refrigerator and allowing the refrigerant to circulate.

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