JP2018115841A - Refrigeration unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly safe refrigeration unit that has a heater member fitted to a bottom plate member of a casing accommodating an outdoor heat exchanger, uses a combustible refrigerant and can prevent occurrence of ignition accidents caused by the heater member as an ignition source.SOLUTION: An air conditioner uses a combustible refrigerant. The air conditioner includes an outdoor heat exchanger 26, an outdoor fan, a casing and a heater member 90. In the outdoor heat exchanger, heat is exchanged between the refrigerant and outside air. The outdoor fan supplies outside air to the outdoor heat exchanger. The casing includes a bottom plate member 55 on which the outdoor heat exchanger is placed, and accommodates the outdoor heat exchanger and the outdoor fan. The heater member is provided at least near a lower end 26a of the outdoor heat exchanger, and is fitted to the bottom plate member. On the bottom plate member, a water introduction groove 552 is formed below the outdoor heat exchanger. A minimum value Lmin of a clearance distance between a bottom surface 552B of the water introduction groove and the lower end of the outdoor heat exchanger is in a range from 10 mm to 20 mm.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a refrigeration apparatus, and more specifically to a refrigeration apparatus that includes a heater member attached to a bottom plate member of a housing that accommodates an outdoor heat exchanger and uses a combustible refrigerant.

In some cases, a flammable refrigerant is used in the refrigeration apparatus. In such a refrigeration apparatus, if the refrigerant leaks out for some reason and becomes a predetermined concentration or more, and there is an ignition source there, a fire accident may occur.

  As an ignition source that can cause such an ignition accident, for example, a heater member mounted on a bottom plate member of a housing that houses an outdoor heat exchanger can be cited. The heater member is used to prevent drain water or the like generated during defrost operation for melting frost adhering to the outdoor heat exchanger from freezing on the bottom plate member.

  In order to prevent an ignition accident using the heater member as an ignition source, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 2015-55455), in a refrigeration apparatus using a combustible refrigerant, the power consumption of the heater member is less than a predetermined value. It is described to suppress.

  However, in reality, the capability required for the heater member varies depending on the outside air temperature, the size of the outdoor unit, and the like, and thus it may be difficult to limit the capability. Further, from the viewpoint of preventing ignition accidents, it is preferable that measures should be taken so that the concentration of the refrigerant does not increase to a level causing the ignition accident around the heater member even if the flammable refrigerant leaks. .

  An object of the present invention is a refrigeration apparatus that includes a heater member that is attached to a bottom plate member of a housing that accommodates an outdoor heat exchanger, and that uses a flammable refrigerant. It is to provide a highly safe refrigeration apparatus that can prevent the above.

  The refrigeration apparatus according to the first aspect of the present invention uses a combustible refrigerant. The refrigeration apparatus includes an outdoor heat exchanger, an outdoor fan, a housing, and a heater member. In the outdoor heat exchanger, heat is exchanged between the refrigerant and the outside air. The outdoor fan supplies outside air to the outdoor heat exchanger. The housing has a bottom plate member on which the outdoor heat exchanger is placed, and accommodates the outdoor heat exchanger and the outdoor fan. The heater member is provided in the vicinity of at least the lower end of the outdoor heat exchanger, and is attached to the bottom plate member. The bottom plate member is formed with a water guide groove below the outdoor heat exchanger. The minimum value of the gap distance between the bottom surface of the water guide groove and the lower end of the outdoor heat exchanger is in the range of 10 mm to 20 mm.

  Conventionally, the distance between the bottom plate member and the lower end of the outdoor heat exchanger is such that air passes (bypasses) between the bottom plate member and the lower end of the outdoor heat exchanger during the operation of the refrigeration apparatus, and the outdoor heat exchange is performed. In order to prevent a reduction in efficiency due to a decrease in the amount of air introduced to the vessel, the air is taken as small as possible. Therefore, in the conventional refrigeration apparatus, even when the outdoor fan is in operation, an air flow hardly occurs in the water guide groove formed in the bottom plate member. For this reason, when the refrigerant leaks in the housing, the refrigerant tends to accumulate in the water guide groove and the concentration tends to increase.

  On the other hand, in the refrigeration apparatus according to the first aspect of the present invention, the minimum distance between the bottom surface of the water guide groove formed below the outdoor heat exchanger and the lower end of the outdoor heat exchanger is a relatively large value of 10 mm or more. Has been taken. Therefore, even if the refrigerant leaks in the housing, it can be prevented that the refrigerant accumulates in the space between the bottom surface of the water guide groove and the lower end of the outdoor heat exchanger provided in the vicinity of the heater member and becomes high concentration. On the other hand, since the minimum distance between the bottom surface of the water guide groove and the lower end of the outdoor heat exchanger does not exceed 20 mm, during operation of the refrigeration apparatus, the outdoor heat exchanger is bypassed and air is passed below the outdoor heat exchanger. Passing excessively can be suppressed.

  The refrigeration apparatus according to the second aspect of the present invention is the refrigeration apparatus according to the first aspect, and is provided between the bottom of the water guide groove having the lowest height position and the lower end of the outdoor heat exchanger. The distance of the gap is 12 mm or more.

  In the refrigeration apparatus according to the second aspect of the present invention, the lower end of the outdoor heat exchanger is arranged 12 mm or more away from the lowermost part of the water guide groove where the refrigerant tends to accumulate. Therefore, even if the refrigerant leaks in the housing, it can be prevented that the refrigerant accumulates at the lowermost portion of the water guide groove and becomes high concentration.

  The refrigeration apparatus according to the third aspect of the present invention is the refrigeration apparatus according to the second aspect, wherein a drain hole is formed in the lowermost part of the water conduit.

  In the refrigeration apparatus according to the third aspect of the present invention, a drain hole is formed at the lowest portion of the water guide groove where the refrigerant concentration tends to increase when the refrigerant leaks. Therefore, the refrigerant can be discharged from the drain hole to the outside of the housing, and even if the refrigerant leaks in the housing, it is further easily prevented that the refrigerant accumulates at the lowermost part of the water guide groove and becomes high concentration.

  The refrigeration apparatus according to the fourth aspect of the present invention is the refrigeration apparatus according to the second aspect or the third aspect, and the heater member is at least partially disposed in the water guide groove. The lowermost part of the water guide groove is not in contact with the heater member.

  In the refrigeration apparatus according to the fourth aspect of the present invention, the heater member is disposed away from the lowermost part of the water guide groove where the concentration of the refrigerant tends to be high. Therefore, even if the refrigerant exists at the lowermost part of the water guide groove, it is possible to prevent a fire accident.

  A refrigeration apparatus according to a fifth aspect of the present invention is the refrigeration apparatus according to any one of the first to fourth aspects, wherein the bottom plate member has a wall portion provided on the periphery. The lower end of the outdoor heat exchanger is positioned lower than the upper end of the wall portion.

  In the refrigeration apparatus according to the fifth aspect of the present invention, the lower end of the outdoor heat exchanger is disposed below the upper end of the wall portion provided on the periphery. Therefore, while the air flow is secured by separating the lower end of the outdoor heat exchanger and the bottom surface of the water guide groove, the outdoor heat exchanger is bypassed and the air under the outdoor heat exchanger is excessively aired when the outdoor fan is operating. Can be prevented from passing.

  In the refrigeration apparatus according to the first aspect of the present invention, the minimum distance between the bottom surface of the water guide groove of the bottom plate member formed below the outdoor heat exchanger and the lower end of the outdoor heat exchanger is a relatively large value of 10 mm or more. It has been. Therefore, even if the refrigerant leaks in the housing, it can be prevented that the refrigerant accumulates in the space between the bottom surface of the water guide groove and the lower end of the outdoor heat exchanger provided in the vicinity of the heater member and becomes high concentration. On the other hand, since the minimum distance between the bottom surface of the water guide groove and the lower end of the outdoor heat exchanger does not exceed 20 mm, during operation of the refrigeration apparatus, the outdoor heat exchanger is bypassed and air is passed below the outdoor heat exchanger. Passing excessively can be suppressed.

  In the refrigeration apparatus according to the second aspect or the third aspect of the present invention, even if the refrigerant leaks in the housing, it is easy to prevent the refrigerant from being accumulated at the lowermost part of the water guide groove and becoming a high concentration.

  In the refrigeration apparatus according to the fourth aspect of the present invention, it is possible to prevent a fire accident even if the refrigerant is present at the lowermost part of the water guide groove.

  In the outdoor unit of the refrigeration apparatus according to the fifth aspect of the present invention, the outdoor heat exchanger is operated during the operation of the outdoor fan while the air flow is secured by separating the lower end of the outdoor heat exchanger and the bottom surface of the water guide groove. Can be bypassed, and excessive passage of air below the outdoor heat exchanger can be suppressed.

It is a schematic block diagram of the air conditioning apparatus which concerns on one Embodiment of the freezing apparatus of this invention. It is a schematic perspective view of the outdoor unit of the freezing apparatus of FIG. It is a schematic plan view of the outdoor unit of FIG. In FIG. 3, drawing of the propeller of the outdoor fan is omitted. FIG. 3 is a schematic plan view of a bottom plate member of the outdoor unit in FIG. 2. FIG. 3 is a schematic rear view of the outdoor unit of FIG. 2 in a state where a top plate and side plates of the housing are removed.

  Hereinafter, an air conditioner 100 according to an embodiment of the refrigeration apparatus of the present invention will be described with reference to the drawings. The following embodiments are merely specific examples of the refrigeration apparatus according to the present invention, and can be appropriately changed without departing from the spirit of the present invention.

(1) Overall Configuration The overall configuration of the air conditioner 100 will be described. FIG. 1 is a schematic configuration diagram of an air conditioner 100. The air conditioner 100 cools and heats the room (the air conditioning target space) in which the indoor unit 60 is arranged. The air conditioner 100 is merely an example of a refrigeration apparatus, and the refrigeration apparatus is not limited to an air conditioner. For example, the refrigeration device may be a chiller, a hot water supply device, a cooling device that cools the inside of a refrigerator or a freezer.

  Here, the air conditioner 100 is a vapor compression refrigeration apparatus. In the air conditioner 100, a flammable refrigerant is used. In the air conditioner 100, a refrigerant having a higher vapor density than air is used. The refrigerant used in the air conditioner 100 is, for example, R32 which is a kind of HFC refrigerant. R32 is flammable and has a vapor density greater than air.

  The combustible refrigerant in the present invention is not limited to R32, and includes other combustible refrigerants. Specifically, the flammable refrigerant of the present invention includes Class 3 (strongly flammable), Class2 (weakly flammable), Subclass2L in accordance with the US ASHRAE 34 Designation and safety classification of refrigerant standard or ISO817 Reference-Designation and safety classification standard. Includes refrigerants that fall under (slightly flammable). R32 is classified as Subclass 2L (slightly flammable) in both of the above standards.

  The air conditioner 100 is a so-called separate type refrigeration apparatus. As shown in FIG. 1, the air conditioner 100 mainly includes an outdoor unit 20, an indoor unit 60, a gas side refrigerant communication pipe 82 and a liquid side refrigerant communication pipe 84 that connect the outdoor unit 20 and the indoor unit 60. Prepare for. In the air conditioner 100, the outdoor unit 20 and the indoor unit 60 are connected via the gas side refrigerant communication pipe 82 and the liquid side refrigerant communication pipe 84, so that the compressor 22 and the outdoor heat exchange of the outdoor unit 20 described later will be described. The refrigerant circuit 10 having the condenser 26, the expansion mechanism 28, the indoor heat exchanger 62 of the indoor unit 60, and the like is configured. In the air conditioner 100, the refrigerant circulates in the refrigerant circuit 10, whereby the air-conditioning target space in which the indoor unit 60 is arranged is cooled or heated. The gas side refrigerant communication pipe 82 and the liquid side refrigerant communication pipe 84 are refrigerant pipes that are constructed on site when the outdoor unit 20 and the indoor unit 60 are installed.

(2) Detailed description Details of the indoor unit 60 and the outdoor unit 20 of the air conditioner 100 will be described.

(2-1) Indoor Unit The indoor unit 60 is installed in the room (air conditioning target space) of the air conditioner 100. The indoor unit 60 is, for example, a ceiling-mounted indoor unit embedded in the ceiling. However, the type of the indoor unit 60 is an example, and the indoor unit 60 may be a wall-hanging or floor-standing indoor unit.

  The indoor unit 60 mainly includes an indoor heat exchanger 62, an indoor fan 64, and an indoor control unit 61 (see FIG. 1).

  The indoor heat exchanger 62 is a heat exchanger that exchanges heat between the indoor air and the refrigerant flowing inside. The indoor heat exchanger 62 is, for example, a cross fin type fin-and-tube heat exchanger. The gas side of the indoor heat exchanger 62 is connected to a gas side refrigerant communication pipe 82 via a gas side pipe 66. The liquid side of the indoor heat exchanger 62 is connected to the liquid side refrigerant communication pipe 84 via the liquid side pipe 68. The indoor heat exchanger 62 functions as a cooler that cools indoor air (an evaporator that evaporates the refrigerant flowing inside) during the cooling operation. The indoor heat exchanger 62 functions as a heater that heats indoor air (a condenser that condenses the refrigerant flowing inside) during heating operation.

  The indoor fan 64 is a fan that supplies indoor air to the indoor heat exchanger 62 and blows out indoor air that has undergone heat exchange with the refrigerant in the indoor heat exchanger 62. The indoor fan 64 is, for example, a centrifugal blower.

  The indoor control unit 61 functions as the control unit 70 together with the outdoor control unit 21 of the outdoor unit 20 described later, and controls the operation of the air conditioner 100. In order to execute this function, the indoor control unit 61 has various electric circuits, a microcomputer, and a memory in which a program executed by the microcomputer is stored. The indoor control unit 61 receives measurement values from various sensors (not shown) included in the indoor unit 60. In addition, the indoor control unit 61 exchanges signals with a remote controller (not shown) for operating the air conditioner 100. Further, the indoor control unit 61 exchanges signals with the outdoor control unit 21 of the outdoor unit 20 described later via the transmission line 70a (see FIG. 1). Control of the operation of the air conditioner 100 by the control unit 70 will be described later.

(2-2) Outdoor unit The outdoor unit 20 is demonstrated referring a figure. FIG. 2 is a schematic perspective view of the outdoor unit 20. FIG. 3 is a schematic plan view of the outdoor unit 20 in a state in which a top plate 54 and side plates (first member 51, right front plate 52, and right rear plate 53) of the casing 50 described later are removed. FIG. 4 is a schematic plan view of the bottom plate member 55 of the casing 50 of the outdoor unit 20. FIG. 5 is a schematic rear view of the outdoor unit 20 with the top plate 54 and side plates removed.

  In the following description, expressions indicating directions such as “up”, “down”, “left”, “right”, “front (front)”, “rear (back)” may be used. Unless otherwise specified, these directions indicate the directions indicated by arrows in FIGS.

  The outdoor unit 20 is installed outdoors (a place different from the room where the indoor unit 60 of the air conditioner 100 is installed). The outdoor unit 20 is installed outdoors, for example.

  The outdoor unit 20 mainly includes a housing 50, a compressor 22, a four-way switching valve 24, an expansion mechanism 28, an accumulator 30, an outdoor fan 32, an outdoor heat exchanger 26, a gas side closing valve 34, and a liquid side closing valve 36. The heater member 90 and the outdoor control unit 21 are included (see FIGS. 1 to 3).

(2-2-1) Connection by piping of component devices Referring to FIG. 1, the compressor 22, the four-way switching valve 24, the outdoor heat exchanger 26, the expansion mechanism 28, the accumulator 30, the gas side shut-off valve 34, and The connection by piping of the component apparatus of the outdoor unit 20 including the liquid side closing valve 36 is demonstrated.

  The suction port of the compressor 22 and the four-way switching valve 24 are connected by a suction pipe 41. The suction pipe 41 is provided with an accumulator 30. The discharge port of the compressor 22 and the four-way switching valve 24 are connected by a discharge pipe 42. The four-way switching valve 24 and the gas side of the outdoor heat exchanger 26 are connected by a first gas side pipe 43. The liquid side of the outdoor heat exchanger 26 and the liquid side shut-off valve 36 are connected by a liquid side pipe 44. The liquid side pipe 44 is provided with an expansion mechanism 28. The four-way switching valve 24 and the gas side closing valve 34 are connected to the second gas side pipe 45.

(2-2-2) Housing The housing 50 has a substantially rectangular parallelepiped shape. The housing 50 includes a compressor 22, a four-way switching valve 24, an expansion mechanism 28, an accumulator 30, an outdoor fan 32, an outdoor heat exchanger 26, a gas side closing valve 34, a liquid side closing valve 36, a heater member 90, and an outdoor unit. Various configurations of the outdoor unit 20 such as the control unit 21 are accommodated.

  The housing 50 includes a first member 51, a right front plate 52, a right rear plate 53, a top plate 54, a bottom plate member 55, and a partition plate 56 (see FIGS. 2 and 3).

  The first member 51 is a member in which a front plate 51a (see FIG. 2) disposed on the left front side of the outdoor unit 20 and a left plate (not shown) disposed on the left side of the outdoor unit 20 are integrally formed. It is. A circular outlet (not shown) is formed in the front plate 51a. A ring-shaped bell mouth (not shown) is attached to the air outlet along the peripheral edge thereof. When the outdoor fan 32 is driven, outdoor air is sucked in from the back side and left side of the outdoor heat exchanger 26, passes through the outdoor heat exchanger 26, and is blown out from the outlet of the front plate 51a (FIG. 3). (See arrows for air flow in). A protective grill 57 is attached to the front plate 51a of the housing 50 in order to prevent contact with the propeller of the outdoor fan 32 described later (see FIG. 2). The protective grill 57 covers the air outlet of the front plate 51a. The protective grill 57 is formed with a plurality of openings for blowing out air.

  The interior of the housing 50 is divided into a blower chamber 200 and a machine chamber 300 by a partition plate 56. In the blower room 200, an outdoor heat exchanger 26 and an outdoor fan 32 are mainly disposed. In the machine room 300, a compressor 22, a four-way switching valve 24, an expansion mechanism 28, and an accumulator 30 are mainly disposed. The partition plate 56 extends upward from the bottom plate member 55 to the top plate 54. Moreover, the partition plate 56 is extended in the curve shape toward the right end of the outdoor heat exchanger 26 from the inner surface side of the front plate 51a (refer FIG. 3). The partition plate 56 suppresses the flow of wind from the blower chamber 200 to the machine chamber 300.

(2-2-1) Bottom plate member The bottom plate member 55 is a member that forms the bottom of the casing 50 of the outdoor unit 20. The bottom plate member 55 is made of, for example, a steel plate. The bottom plate member 55 is formed by press working. On the bottom plate member 55, a support base 32a for supporting the compressor 22, the outdoor heat exchanger 26, the outdoor fan 32, and the like are placed. A heater member 90 is attached to the bottom plate member 55.

  The bottom plate member 55 includes a substantially rectangular bottom plate portion 551 (see FIG. 4) that constitutes the lower surface of the housing 50, and a wall portion 556 (see FIG. 5) provided on the periphery of the bottom plate portion 551.

  In the present embodiment, the wall portion 556 is provided so as to surround the periphery of the bottom plate portion 551. The wall portion 556 extends vertically upward from the periphery of the bottom plate portion 551. The first member 51, the right rear plate 53, and the like are fixed to the wall portion 556 by a fastening member such as a screw.

  A water guide groove 552 is formed in the bottom plate portion 551. The water guide groove 552 is configured to remove rain blown into the outdoor unit 20, water melted with snow blown into the outdoor unit 20, condensed water, or water melted with frost attached to the outdoor heat exchanger 26. It is a groove for discharging to the outside. The water guide groove 552 is formed in the bottom plate portion 551 so as to be recessed downward.

  A position where the water guide groove 552 is formed (path of the water guide groove 552) will be described with reference to FIGS.

  The water guide groove 552 extends in the vicinity of the right end of the bottom plate member 55 along the right end of the bottom plate member 55 from the center of the bottom plate member 55 in the front-rear direction to the vicinity of the right rear corner of the bottom plate member 55. Further, the water guide groove 552 extends in the vicinity of the rear end portion of the bottom plate member 55 from the vicinity of the right rear corner of the bottom plate member 55 to the vicinity of the left rear corner along the rear end portion of the bottom plate member 55. In addition, the water guide groove 552 is located in the vicinity of the left end portion of the bottom plate member 55 along the left end portion of the bottom plate member 55 from the vicinity of the left rear corner of the bottom plate member 55 to the front, and the central portion (outdoors) It extends to the vicinity of the left front end of the heat exchanger 26). Furthermore, the water guide groove 552 extends from the vicinity of the left front end of the outdoor heat exchanger 26 to the vicinity of the partition plate 56 toward the right side. A part of the water guide groove 552 (a part of the portion extending near the rear end portion of the bottom plate member 55 along the rear end portion and the portion of the bottom plate member 55 extending near the left end portion along the left end portion) It is formed below the exchanger 26.

  In the water guide groove 552, a plurality of concave portions 554, 555 recessed downward are formed (see FIG. 4). When the outdoor unit 20 is installed, the bottom surface of one recess 555 is lower in height than the bottom surfaces of other recesses 554. In addition, in the state where the outdoor unit 20 is installed, the bottom surface of the recess 555 has the lowest height among the bottom surfaces 552B of the water guide grooves 552 including the bottom surface of the recess 555. Here, the bottom surface of the recess 555 having the lowest height position in the bottom surface 552B of the water guide groove 552 is referred to as a water guide groove lowermost part 552BL. A drain hole 555a for discharging the water that has flowed through the water guide groove 552 to the outside of the housing 50 is formed in the bottom surface of the recess 555, that is, the water guide groove lowermost part 552BL (see FIG. 4). Further, a drain hole 554a for discharging the water flowing through the water guide groove 552 to the outside of the housing 50 is also formed on the bottom surface of the recess 554 (see FIG. 4).

  The water guide groove 552 is sloped so as to gradually decrease from the end of the water guide groove 552 toward the concave portion 555 along the water guide groove 552 in order to promote water discharge. That is, the water guide groove 552 is inclined so as to gradually become lower in the direction of the arrow in FIG. In FIG. 5, only the water guide groove 552 on the rear end side of the bottom plate member 55 is drawn, but the water guide groove 552 is inclined so as to gradually become lower toward the recess 555. Note that FIG. 5 exaggerates the gradient of the water guide groove 552 for explanation, and does not represent the actual gradient of the water guide groove 552.

  The water guide groove 552 may be provided with a gradient only in a part thereof. Further, the water guide groove 552 may not be provided with a gradient. However, in order to promote the discharge of water, it is preferable that the water guide groove 552 be provided with a gradient.

  A part of the heater member 90 attached to the bottom plate member 55 is disposed below the outdoor heat exchanger 26 (see FIG. 3). In addition, the heater member 90 is arrange | positioned over the substantially whole region below the outdoor heat exchanger 26 from the right rear end part of a outdoor heat exchanger to the left front end part along the direction where the outdoor heat exchanger 26 is extended. It is preferable. In the present embodiment, the heater member 90 is disposed in the water guide groove 552 below the outdoor heat exchanger 26 (see FIG. 3). In addition, in this embodiment, although the heater member 90 arrange | positioned under the outdoor heat exchanger 26 is entirely arrange | positioned in the water conveyance groove | channel 552, it is not limited to this. For example, a part of the heater member 90 disposed below the outdoor heat exchanger 26 may be disposed outside the water guide groove 552. However, in order to prevent freezing of water below the outdoor heat exchanger 26 and further to prevent freezing of water flowing in the water guide groove 552 by the heater member 90, the outdoor heat exchanger 26 of the heater member 90. As for the part arrange | positioned below, it is preferable that the whole is arrange | positioned in the water guide groove 552. FIG.

  A part of the heater member 90 attached to the bottom plate member 55 is disposed in a water guide groove 552 extending from the vicinity of the left front end of the outdoor heat exchanger 26 to the partition plate 56 on the right side (see FIG. 3). ).

  The heater member 90 is attached to the bottom plate member 55 by being fixed to the bottom surface 552B by a plurality of fixing members 92 provided on the bottom surface 552B of the water guide groove 552. The heater member 90 is in a state where it is in contact with the bottom surface 552B of the water guide groove 552 or in the vicinity of the bottom surface 552B of the water guide groove 552, particularly in the vicinity of the fixing member 92. However, since the water guide groove 552 is provided with a gradient, at least a part of the heater member 90 is disposed in the water guide groove 552 without contacting the bottom surface 552B of the water guide groove 552. In particular, the bottom surfaces of the recesses 554 and 555 in the bottom surface 552B of the water guide groove 552 are recessed below the bottom surface 552B around the recesses 554 and 555, so that the bottom surfaces of the recesses 554 and 555 do not contact the heater member 90. That is, the lowest water guide groove 552BL (the bottom surface of the recess 555) of the bottom surface 552B of the water guide groove 552 is not in contact with the heater member 90.

(2-2-3) Compressor The compressor 22 sucks and compresses the low-pressure refrigerant in the refrigeration cycle via the suction pipe 41, and discharges the high-pressure refrigerant in the refrigeration cycle via the discharge pipe 42. The compressor 22 is, for example, a positive displacement compressor. The compressor 22 is, for example, an inverter type compressor that can control the rotation speed of the motor. The compressor 22 is placed on the bottom plate member 55 of the housing 50.

(2-2-4) Four-way switching valve The four-way switching valve 24 switches the flow direction of the refrigerant when the air-conditioning apparatus 100 is switched between the cooling operation and the heating operation. During the cooling operation, the four-way switching valve 24 connects the discharge pipe 42 and the first gas side pipe 43 and connects the suction pipe 41 and the second gas side pipe 45 (see the solid line in FIG. 1). During the heating operation, the four-way selector valve 24 connects the discharge pipe 42 and the second gas side pipe 45, and connects the suction pipe 41 and the first gas side pipe 43 (see the broken line in FIG. 1).

(2-2-5) Expansion Mechanism The expansion mechanism 28 is a mechanism that expands the refrigerant flowing through the liquid side pipe 44 and adjusts the pressure and flow rate of the refrigerant. The expansion mechanism 28 is, for example, an electric valve capable of adjusting the opening degree.

(2-2-6) Accumulator The accumulator 30 has a gas-liquid separation function for separating a gas-liquid two-phase refrigerant into a gas phase and a liquid phase. The compressor 22 is supplied with a gas-phase refrigerant separated by the accumulator 30 and collected in the upper space of the accumulator 30.

(2-2-7) Outdoor Fan The outdoor fan 32 is a fan that supplies outdoor air to the outdoor heat exchanger 26. The outdoor fan 32 is, for example, a propeller fan. In FIG. 3, the drawing of the propeller of the outdoor fan 32 is omitted from the viewpoint of easy viewing of the arrangement of the heater member 90 attached to the bottom plate member 55 of the housing 50. The outdoor fan 32 is supported by a support base 32 a fixed to the bottom plate member 55.

  The outdoor fan 32 takes in outdoor air from the outside of the housing 50 (the back side and the left side of the housing 50). The outdoor air taken into the housing 50 passes through the outdoor heat exchanger 26 and is then discharged out of the housing 50 through an air outlet (not shown) formed in the front plate 51a of the housing 50. . That is, when the outdoor fan 32 rotates, the air moves as indicated by arrows indicating the air flow in FIG.

(2-2-8) Outdoor heat exchanger The outdoor heat exchanger 26 is a heat exchanger in which heat is exchanged between outdoor air and a refrigerant flowing inside. The outdoor heat exchanger 26 is, for example, a cross fin type fin-and-tube heat exchanger. The outdoor heat exchanger 26 functions as a condenser that exhausts heat from the refrigerant to the outdoor air and condenses the refrigerant flowing inside during the cooling operation. The outdoor heat exchanger 26 functions as an evaporator that absorbs heat from the outdoor air to the refrigerant and evaporates the refrigerant flowing inside during the heating operation.

  The outdoor heat exchanger 26 extends leftward from the vicinity of the rear end of the partition plate 56 along the back side of the casing 50, changes its direction near the left rear corner of the casing 50, and changes the casing 50. It extends forward along the left side plate (see the one-dot chain line in FIG. 3).

  The outdoor heat exchanger 26 is placed on the bottom plate portion 551 of the bottom plate member 55 of the housing 50 via a support portion 558 (see FIG. 5). The support portion 558 is a member that is installed on the bottom plate portion 551 of the bottom plate member 55 and supports the outdoor heat exchanger 26 from below. Although the position and quantity of the support part 558 are not limited, the support part 558 is in the water guide groove 552, near the right rear end of the outdoor heat exchanger 26, and on the left rear side of the outdoor heat exchanger 26. 3 near the corner on the side and near the end on the left front side of the outdoor heat exchanger 26.

  The arrangement of the outdoor heat exchanger 26 with respect to the bottom plate member 55 will be described.

  A portion of the outdoor heat exchanger 26 that extends in the left-right direction on the back side of the bottom plate member 55 is disposed about 10 mm forward of the wall portion 556 on the back side of the bottom plate member 55. For example, the portion extending in the left-right direction on the back side of the bottom plate member 55 of the outdoor heat exchanger 26 is preferably disposed about 8 to 15 mm forward of the wall portion 556 on the back side of the bottom plate member 55.

  Further, the portion of the outdoor heat exchanger 26 that extends in the front-rear direction on the left side of the bottom plate member 55 is disposed about 10 mm to the right of the left side wall portion 556 of the bottom plate member 55. For example, the portion extending in the front-rear direction on the left side of the bottom plate member 55 of the outdoor heat exchanger 26 is preferably disposed 8 to 15 mm to the right of the left side wall portion 556 of the bottom plate member 55.

  The outdoor heat exchanger 26 has a casing so that the minimum value of the gap between the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552 formed below the outdoor heat exchanger 26 is 10 mm or more. 50. In the present embodiment, the gap between the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552 is minimized due to the gradient of the water guide groove 552, on the right rear side of the outdoor heat exchanger 26. Or the vicinity of the left front end of the outdoor heat exchanger 26. In the present embodiment, the gap is minimized between the vicinity of the right rear end of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552 (see FIG. 5). The position where the gap between the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552 is minimized is near the right rear end of the outdoor heat exchanger 26 or the outdoor heat exchanger 26. It does not have to be near the end on the left front side. The minimum value Lmin (see FIG. 5) of the gap between the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552 is preferably in the range of 10 mm to 20 mm. Since the minimum value Lmin is in the range of 10 mm to 20 mm, the bottom surface 552B of the water guide groove 552 is used when the outdoor fan 32 is operated or when the wind is blowing even when the outdoor fan 32 is stopped. And air easily flows between the heater member 90 and the lower end 26a of the outdoor heat exchanger 26 provided in the vicinity. Therefore, even if the refrigerant leaks in the housing 50, it is possible to prevent the refrigerant from accumulating in the space between the bottom surface 552B of the water guide groove 552 and the lower end 26a of the outdoor heat exchanger 26 and increasing the concentration. On the other hand, since the minimum distance between the bottom surface 552B of the water guide groove 552 of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26 does not exceed 20 mm, the outdoor heat exchanger 26 is bypassed when the air conditioner 100 is operated. The air can be prevented from passing excessively below the outdoor heat exchanger 26.

  As described above, in the air conditioner 100 of the present embodiment, since the density of the refrigerant is greater than that of air, the refrigerant is particularly likely to accumulate in a low place. Specifically, among the water guide grooves 552 formed so as to be recessed downward in the bottom plate portion 551 of the bottom plate member 55, the coolant is particularly likely to accumulate in the lowest water guide groove lowermost part 552BL. Therefore, it is preferable that the distance between the lowermost water guide groove 552BL of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26 is 12 mm or more. That is, it is preferable that the maximum value Lmax (see FIG. 5) of the gap between the water guide groove lowermost part 552BL of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26 is 12 mm or more. As a result, even if the refrigerant leaks in the housing 50, an air flow is generated in the gap between the water guide groove bottom 552BL of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26, and the water guide groove bottom It is possible to prevent the refrigerant from being accumulated in 552BL and becoming a high concentration.

  Regarding the height relationship between the outdoor heat exchanger 26 and the wall portion 556 of the bottom plate member 55, the lower end 26 a of the outdoor heat exchanger 26 is preferably located lower than the upper end 556 a of the wall portion 556. With this configuration, when the outdoor fan 32 is in operation, the outdoor heat exchanger 26 can be bypassed, and excessive passage of air below the outdoor heat exchanger 26 can be suppressed.

(2-2-9) Gas-side shutoff valve The gas-side shutoff valve 34 is connected to the gas-side refrigerant communication pipe 82 and the second gas-side pipe 45, and the gas-side refrigerant communication pipe 82 and the second gas-side pipe 45 are connected to each other. This is a valve that switches between communication and non-communication.

  During the operation of the air conditioner 100, the gas-side shut-off valve 34 is opened, and the second gas-side pipe 45 and the gas-side refrigerant communication pipe 82 communicate with each other. During the operation of the air conditioner 100, a gas-phase refrigerant mainly flows through the gas-side closing valve 34.

(2-2-10) Liquid-side shutoff valve The liquid-side shutoff valve 36 has a liquid-side refrigerant communication pipe 84 and a liquid-side pipe 44 connected to each other, and communication / non-connection between the liquid-side refrigerant communication pipe 84 and the liquid-side pipe 44. It is a valve that switches communication.

  When the air conditioner 100 is in operation, the liquid side shut-off valve 36 is opened, and the liquid side pipe 44 and the liquid side refrigerant communication pipe 84 communicate with each other. During operation of the air conditioner 100, liquid phase refrigerant mainly flows through the liquid side shut-off valve 36.

(2-2-11) Heater Member The heater member 90 is a heater that prevents water from freezing at the bottom plate member 55 of the housing 50. The heater member 90 is a metallic tubular member in which a heating wire such as a nichrome wire is incorporated. The heater member 90 is provided in the vicinity of the lower end 26 a of the outdoor heat exchanger 26 and is attached to the bottom plate member 55. The heating capacity of the heater member 90 is determined according to, for example, an assumed use condition (outside air temperature or the like).

  The heater member 90 is arranged on the bottom plate portion 551 of the bottom plate member 55 in a loop shape. The heater member 90 is located on the left front side of the outdoor heat exchanger 26 from the vicinity of the right rear side end of the outdoor heat exchanger 26 so as to substantially follow the outdoor heat exchanger 26 from the vicinity of the right rear corner of the outdoor unit 20. It extends to the vicinity of the end (see FIG. 3). The heater member 90 extends in the right direction from the vicinity of the left front end of the outdoor heat exchanger 26 to the vicinity of the partition plate 56, further changes the direction, and further extends rearward. Return to the vicinity of the right rear corner of the outdoor unit 20 (see FIG. 3). The heater member 90 extends in the water guide groove 552 of the bottom plate member 55 along the lower end 26a of the outdoor heat exchanger 26. Further, the heater member 90 extends in the water guide groove 552 of the bottom plate member 55 from the vicinity of the left front end of the outdoor heat exchanger 26 to the vicinity of the partition plate 56. A portion of the heater member 90 that extends in the front-rear direction in the vicinity of the partition plate 56 is disposed not in the water guide groove 552 of the bottom plate portion 551 of the bottom plate member 55 but in a position higher than the bottom surface 552B of the water guide groove 552.

  In addition, the laying path | route of the heater member 90 shown here is an illustration, and the laying path | route of the heater member 90 is not limited to the form of an indication. However, a heater member 90 is preferably provided at least near the lower end 26a of the outdoor heat exchanger 26. In order to prevent water from freezing in the water guide groove 552, the heater member 90 is preferably disposed at least partially in the water guide groove 552. In particular, the heater member 90 disposed below the outdoor heat exchanger 26 is preferably disposed in the water guide groove 552.

(2-2-12) Outdoor Control Unit The outdoor control unit 21 functions as the control unit 70 together with the indoor control unit 61 of the indoor unit 60 and controls the operation of the air conditioner 100. In order to execute this function, the outdoor control unit 21 includes various electric circuits, a microcomputer, and a memory in which a program executed by the microcomputer is stored. The outdoor control unit 21 receives measurement values from various sensors (not shown) included in the outdoor unit 20. In addition, the outdoor control unit 21 exchanges signals with the indoor control unit 61 of the indoor unit 60 via the transmission line 70a (see FIG. 1).

  The control unit 70 controls each unit of the air conditioner 100 so that the air conditioner 100 performs the following operation during the cooling operation and the heating operation. The control mode of the air conditioner 100 is an example, and the operation mode of the air conditioner 100 is not limited.

  During the cooling operation, the control unit 70 operates the compressor 22 with the four-way switching valve 24 being switched to the state indicated by the solid line in FIG. Then, the control unit 70 controls the load of the compressor 22 so that the evaporation temperature in the refrigeration cycle becomes a target value, and controls the expansion mechanism 28 so that the degree of supercooling becomes a predetermined value.

  During the heating operation, the control unit 70 operates the compressor 22 in a state where the four-way switching valve 24 is switched to the state indicated by the broken line in FIG. Then, the control unit 70 controls the load of the compressor 22 so that the condensation temperature in the refrigeration cycle becomes a target value, and controls the expansion mechanism 28 so that the degree of supercooling becomes a predetermined value. In addition, when the temperature of the outdoor heat exchanger 26 becomes a predetermined temperature or lower during the heating operation, a defrost operation is performed to remove frost attached to the outdoor heat exchanger 26. For example, the air conditioner 100 performs a so-called reverse cycle defrost operation in which the four-way switching valve 24 is switched so that the refrigerant flows in the same direction as in the cooling operation in order to remove frost attached to the outdoor heat exchanger 26. .

  Further, the control unit 70 operates the heater member 90 during the defrost operation so that water generated by frost melting in the outdoor heat exchanger 26 does not freeze in the bottom plate member 55. Further, the controller 70 prevents the rain or snow blown into the outdoor unit 20 from freezing on the bottom plate member 55 when the outside air temperature becomes a predetermined temperature or less even when the air conditioner 100 is not in operation. The heater member 90 is operated.

  In addition, when the air conditioner 100 is stopped, the control unit 70 intermittently shortens the outdoor fan 32 in order to prevent the detected temperature of a sensor (not shown) that detects the outdoor temperature from deviating from the actual outdoor temperature. Operate the fan intermittently to eliminate air stagnation by operating for hours. Even if the refrigerant leaks in the housing 50 while the air conditioner 100 is stopped due to the intermittent fan operation, the outdoor heat exchanger 26 in which the bottom surface 552B of the water guide groove 552 and the heater member 90 are provided in the vicinity. It is easy to prevent the refrigerant from accumulating in the space between the lower end 26a and high concentration.

(3) Features (3-1)
The air conditioner 100 of this embodiment uses a flammable refrigerant. The air conditioner 100 includes an outdoor heat exchanger 26, an outdoor fan 32, a housing 50, and a heater member 90. In the outdoor heat exchanger 26, heat exchange is performed between the refrigerant and the outside air. The outdoor fan 32 supplies outside air to the outdoor heat exchanger 26. The housing 50 includes a bottom plate member 55 on which the outdoor heat exchanger 26 is placed, and accommodates the outdoor heat exchanger 26 and the outdoor fan 32. The heater member 90 is provided at least in the vicinity of the lower end 26 a of the outdoor heat exchanger 26 and is attached to the bottom plate member 55. A water guide groove 552 is formed in the bottom plate member 55 below the outdoor heat exchanger 26. The minimum value Lmin of the gap distance between the bottom surface 552B of the water guide groove 552 and the lower end 26a of the outdoor heat exchanger 26 is in the range of 10 mm to 20 mm.

  Conventionally, the distance between the bottom plate member and the lower end of the outdoor heat exchanger is such that the air bypasses between the bottom plate member and the lower end of the outdoor heat exchanger during operation of the refrigeration apparatus, and is led to the outdoor heat exchanger. In order to prevent a reduction in efficiency due to a decrease in the amount of air, it is taken as small as possible. Therefore, in the conventional refrigeration apparatus, even when the outdoor fan is in operation, an air flow hardly occurs in the water guide groove formed in the bottom plate member. For this reason, when the refrigerant leaks in the housing, the refrigerant tends to accumulate in the water guide groove and the concentration tends to increase.

  On the other hand, in the air conditioner 100 of the present embodiment, the minimum distance between the bottom surface 552B of the water guide groove 552 formed below the outdoor heat exchanger 26 and the lower end 26a of the outdoor heat exchanger 26 is relatively large as 10 mm or more. Taken into value. Therefore, even if the refrigerant leaks in the housing 50, the refrigerant accumulates in the space between the bottom surface 552B of the water guide groove 552 and the lower end 26a of the outdoor heat exchanger 26 provided near the heater member 90. Can be prevented. On the other hand, since the minimum distance between the bottom surface 552B of the water guide groove 552 and the lower end 26a of the outdoor heat exchanger 26 does not exceed 20 mm, the outdoor heat exchanger 26 is bypassed during the operation of the air conditioner 100, and the outdoor heat exchange is performed. It is possible to suppress excessive passage of air below the vessel 26.

(3-2)
In the air conditioner 100 of the present embodiment, the distance of the gap between the water guide groove bottom 552BL having the lowest height position among the bottom surfaces 552B of the water guide grooves 552 and the lower end 26a of the outdoor heat exchanger 26 is 12 mm or more. .

  In the air conditioner 100 of the present embodiment, the lower end 26a of the outdoor heat exchanger 26 is disposed 12 mm or more away from the lowermost portion of the water guide groove 552 where the refrigerant is likely to accumulate. Therefore, even if the refrigerant leaks in the housing 50, it is possible to prevent the refrigerant from collecting in the water guide groove lowermost part 552BL and increasing its concentration.

(3-3)
In the air conditioner 100 of the present embodiment, a drain hole 555a is formed in the water conveyance groove lowermost part 552BL.

  In the air conditioner 100 of the present embodiment, the drain hole 555a is formed in the water guide groove lowermost part 552BL where the refrigerant concentration tends to increase when the refrigerant leaks. Therefore, the refrigerant can also be discharged from the drain hole 555a to the outside of the housing 50, and even if the refrigerant leaks in the housing 50, the refrigerant is prevented from being accumulated in the water guide groove lowermost part 552BL and becoming a high concentration. Easy to be.

(3-4)
In the air conditioner 100 of this embodiment, the heater member 90 is at least partially disposed in the water guide groove 552. The water guide groove lowermost part 552BL is not in contact with the heater member 90.

  In the air conditioner 100 of the present embodiment, the heater member 90 is disposed away from the water guide groove lowermost portion 552BL where the refrigerant concentration tends to be high. Therefore, even if the refrigerant exists in the water guide groove lowermost part 552BL, a fire accident can be prevented.

(3-5)
In the air conditioner 100 of the present embodiment, the bottom plate member 55 has a wall portion 556 provided on the periphery. The lower end 26 a of the outdoor heat exchanger 26 is positioned lower than the upper end 556 a of the wall portion 556.

  In the air conditioner 100 according to the fifth aspect of the present invention, the lower end 26a of the outdoor heat exchanger 26 is disposed below the upper end 556a of the wall portion 556 provided at the periphery. Therefore, the outdoor heat exchanger 26 is bypassed during the operation of the outdoor fan 32 while the air flow is secured by separating the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552, and the outdoor heat exchanger It is possible to suppress excessive passage of air below 26.

(4) Modification A modification of the air conditioner 100 according to the above embodiment is shown. Note that the modified examples may be combined as appropriate within a range that does not contradict each other.

(4-1) Modification A
In the air conditioner 100 of the above embodiment, the heater member 90 is fixed to the bottom surface 552B of the water guide groove 552, but is not limited thereto.

  For example, the heater member 90 may be fixed to the side surface of the water guide groove 552 formed in the bottom plate portion 551 by the fixing member 92. Since the heater member 90 is less likely to come into contact with the bottom surface 552B of the water guide groove 552 by being formed in this way, the refrigerant having a density higher than that of air leaks in the outdoor unit 20 and the refrigerant near the bottom surface 552B of the water guide groove 552. Even if it is guided, it is easy to prevent a fire accident.

(4-2) Modification B
Like the air conditioner 100 of the said embodiment, although the recessed part 554,555 is provided in the water conveyance groove | channel 552, and it is preferable that the drain holes 554a, 555a are provided in the recessed parts 554,555, it is not limited to this. .

  For example, a drain hole may be directly formed in the water guide groove 552 (without providing the recesses 554 and 555). As in the above embodiment, when the water guide groove 552 is inclined, the water guide groove whose height position is the lowest among the bottom surfaces 552B of the water guide groove 552 even when the recesses 554, 555 are not provided. It is possible to avoid the heater member 90 from contacting the lowermost part.

(4-3) Modification C
In the air conditioner 100 of the above embodiment, the wall portion 556 is formed so as to surround the entire circumference of the bottom plate member 55, but is not limited to this. For example, the wall portion 556 may not be provided in a partial region of the peripheral edge of the bottom plate member 55. Further, the bottom plate member 55 may not have the wall portion 556.

  However, since the bottom plate member 55 has the wall portion 556 along the outdoor heat exchanger 26, the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the water guide groove 552 are separated from each other while ensuring the air flow. During the operation of the fan 32, the outdoor heat exchanger 26 can be bypassed, and excessive passage of air below the outdoor heat exchanger 26 can be suppressed.

(4-4) Modification D
In addition to the outdoor heat exchanger 26 and the outdoor fan 32, the air conditioner 100 according to the embodiment includes the outdoor unit 20 in which the configuration of the compressor 22 and the like is housed in the housing 50. However, in the air conditioner 100, instead of the outdoor unit 20 described above, the heat exchanger unit in which the outdoor heat exchanger 26 and the outdoor fan 32 are housed in the housing, the compressor 22 and the like are housed in the housing. The apparatus provided with the compressor unit different from a heat exchanger unit may be sufficient.

  INDUSTRIAL APPLICABILITY The present invention includes a heater member that is attached to a bottom plate member of a housing that accommodates an outdoor heat exchanger, and can be widely applied to a refrigeration apparatus that uses a flammable refrigerant.

26 Outdoor heat exchanger 26a Lower end (lower end of outdoor heat exchanger)
32 Outdoor fan 50 Housing 55 Bottom plate member 90 Heater member 100 Refrigeration device 552 Water guide groove 552B Bottom surface 552BL Water guide groove bottom 555a Drain hole 556 Wall portion 556a Upper end (upper end of wall portion)
Lmin minimum value

Japanese Patent Laying-Open No. 2015-55455

Claims (5)

A refrigeration apparatus using a flammable refrigerant,
An outdoor heat exchanger (26) in which heat is exchanged between the refrigerant and outside air;
An outdoor fan (32) for supplying outside air to the outdoor heat exchanger;
A housing (50) having a bottom plate member (55) on which the outdoor heat exchanger is placed, and housing the outdoor heat exchanger and the outdoor fan;
A heater member (90) provided at least in the vicinity of the lower end (26a) of the outdoor heat exchanger and attached to the bottom plate member;
With
In the bottom plate member, a water guide groove (552) is formed below the outdoor heat exchanger,
The minimum value (Lmin) of the gap distance between the bottom surface of the water guiding groove (552B) and the lower end of the outdoor heat exchanger is in the range of 10 mm to 20 mm.
Refrigeration apparatus (100). The distance of the gap between the bottom of the water guide groove (552BL) having the lowest height position among the bottom surfaces of the water guide grooves and the lower end of the outdoor heat exchanger is 12 mm or more.
The refrigeration apparatus according to claim 1. A drain hole (555a) is formed at the lowermost part of the water guide groove.
The refrigeration apparatus according to claim 2. The heater member is at least partially disposed within the water channel;
The lowermost part of the water guide groove is not in contact with the heater member.
The refrigeration apparatus according to claim 2 or 3. The bottom plate member has a wall portion (556) provided on the periphery,
The lower end of the outdoor heat exchanger is located lower than the upper end (556a) of the wall portion,
The refrigeration apparatus according to any one of claims 1 to 4.

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