JP7071613B2 - Refrigeration equipment - Google Patents

Description

The present invention relates to a freezing device, and more specifically, to a freezing device including a heater member mounted on a bottom plate member of a housing accommodating an outdoor heat exchanger and using a flammable refrigerant.

Flammable refrigerants may be used in refrigeration equipment. In such a refrigerating apparatus, if the refrigerant leaks out for some reason and the concentration becomes equal to or higher than a predetermined concentration and an ignition source is present there, an ignition accident may occur.

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

In order to prevent an ignition accident using a heater member as an ignition source, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 2015-55455), in a refrigerating apparatus using a flammable refrigerant, the power consumption of the heater member is reduced to a predetermined value or less. It is described that it is suppressed.

However, in reality, the capacity required for the heater member changes depending on the outside air temperature, the size of the outdoor unit, and the like, so it may be difficult to limit the capacity. From the viewpoint of preventing ignition accidents, it is preferable to take measures so that even if flammable refrigerant leaks, the concentration of the refrigerant does not increase to a level that causes an ignition accident around the heater member. ..

The subject of the present invention is a refrigerating apparatus provided with a heater member mounted on a bottom plate member of a housing accommodating an outdoor heat exchanger and using a flammable refrigerant, and an ignition accident occurs using the heater member as an ignition source. The purpose is to provide a highly safe refrigerating device that can prevent the above.

The refrigerating apparatus according to the first aspect of the present invention uses a flammable refrigerant. The refrigerating 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 houses the outdoor heat exchanger and the outdoor fan. The heater member is provided at least in the vicinity of the lower end of the outdoor heat exchanger and is attached to the bottom plate member. A water guide groove is formed below the outdoor heat exchanger in the bottom plate member. The minimum distance between the bottom of the headrace and the bottom 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 refrigerating apparatus to exchange outdoor heat. It is taken as small as possible to prevent the amount of air guided to the vessel from decreasing and reducing efficiency. Therefore, in the conventional refrigerating apparatus, it is difficult for air to flow in the water guide groove formed in the bottom plate member even while the outdoor fan is in operation. Therefore, when the refrigerant leaks in the housing, the refrigerant tends to accumulate in the headrace groove and the concentration tends to increase.

On the other hand, in the refrigerating apparatus according to the first aspect of the present invention, the minimum distance between the bottom surface of the water guiding 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 is possible to prevent the refrigerant from accumulating in the space between the bottom surface of the headrace groove and the lower end of the outdoor heat exchanger provided in the vicinity of the heater member to have a high concentration. On the other hand, since the minimum distance between the bottom surface of the water conveyance groove and the lower end of the outdoor heat exchanger does not exceed 20 mm, the air flows under the outdoor heat exchanger by bypassing the outdoor heat exchanger when the refrigerating device is operated. It is possible to suppress excessive passage.

The refrigerating apparatus according to the second aspect of the present invention is the refrigerating apparatus according to the first aspect, and is located between the lowermost portion of the headrace groove having the lowest height position among the bottom surfaces of the headrace groove and the lower end of the outdoor heat exchanger. The gap distance is 12 mm or more.

In the refrigerating apparatus according to the second aspect of the present invention, the lower end of the outdoor heat exchanger is arranged at a distance of 12 mm or more from the lowermost portion of the headrace groove where the refrigerant tends to collect. Therefore, even if the refrigerant leaks in the housing, it is possible to prevent the refrigerant from accumulating at the lowermost portion of the headrace groove and having a high concentration.

The refrigerating apparatus according to the third aspect of the present invention is the refrigerating apparatus according to the second aspect, and a drain hole is formed at the lowermost portion of the headrace groove.

In the refrigerating apparatus according to the third aspect of the present invention, a drain hole is formed at the lowermost portion of the headrace groove where the concentration of the refrigerant tends to increase when the refrigerant leaks. Therefore, the refrigerant can be discharged to the outside of the housing from the drain hole, and even if the refrigerant leaks inside the housing, it is more likely to prevent the refrigerant from accumulating at the lowermost portion of the headrace groove and becoming high in concentration.

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

In the refrigerating apparatus according to the fourth aspect of the present invention, the heater member is arranged away from the lowermost portion of the headrace groove where the concentration of the refrigerant tends to be high. Therefore, even if the refrigerant is present at the bottom of the headrace groove, it is possible to prevent an ignition accident.

The refrigerating apparatus according to the fifth aspect of the present invention is the refrigerating apparatus according to any one of the first to fourth aspects, and the bottom plate member has a wall portion provided on the peripheral edge. The lower end of the outdoor heat exchanger is located below the upper end of the wall.

In the refrigerating apparatus according to the fifth aspect of the present invention, the lower end of the outdoor heat exchanger is arranged below the upper end of the wall portion provided on the peripheral edge. Therefore, while ensuring the air flow by separating the lower end of the outdoor heat exchanger from the bottom of the headrace groove, when operating the outdoor fan, the outdoor heat exchanger is bypassed and the air below the outdoor heat exchanger is excessively aired. Can be suppressed from passing through.

In the refrigerating 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 set to a relatively large value of 10 mm or more. Has been done. Therefore, even if the refrigerant leaks in the housing, it is possible to prevent the refrigerant from accumulating in the space between the bottom surface of the headrace groove and the lower end of the outdoor heat exchanger provided in the vicinity of the heater member to have a high concentration. On the other hand, since the minimum distance between the bottom surface of the water conveyance groove and the lower end of the outdoor heat exchanger does not exceed 20 mm, the air flows under the outdoor heat exchanger by bypassing the outdoor heat exchanger when the refrigerating device is operated. It is possible to suppress excessive passage.

In the refrigerating 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 accumulating at the lowermost portion of the headrace groove and becoming a high concentration.

In the refrigerating apparatus according to the fourth aspect of the present invention, even if the refrigerant is present at the lowermost part of the headrace groove, it is possible to prevent an ignition accident.

In the outdoor unit of the refrigerating apparatus according to the fifth aspect of the present invention, the outdoor heat exchanger is operated during the operation of the outdoor fan while ensuring the air flow by keeping the distance between the lower end of the outdoor heat exchanger and the bottom surface of the headrace groove. Can be bypassed to prevent excessive air passage under the outdoor heat exchanger.

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

Hereinafter, the air conditioner 100 according to the embodiment of the refrigerating apparatus of the present invention will be described with reference to the drawings. The following embodiments are merely specific examples of the refrigerating 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 (air conditioning target space) in which the indoor unit 60 is arranged. The air conditioner 100 is only an example of a refrigerating device, and the refrigerating device is not limited to the air conditioner. For example, the refrigerating device may be a chiller, a hot water supply device, a cooling device for cooling the inside of a refrigerator or a freezer, and the like.

Here, the air conditioner 100 is a steam compression type refrigerating device. A flammable refrigerant is used in the air conditioner 100. Further, in the air conditioner 100, a refrigerant having a vapor density higher than that of air is used. The refrigerant used in the air conditioner 100 is, for example, R32, which is a kind of HFC-based refrigerant. R32 is flammable and has a higher vapor density than air.

The flammable refrigerant in the present invention is not limited to R32, and includes other flammable refrigerants. Specifically, the combustible refrigerant of the present invention includes Class3 (high flame), Class2 (weak flame), and Subclass 2L according to the US ASHRAE34 Designation and safety classification of refrigerant standard or ISO817 Referrants- Designation and safety classification standard. Contains refrigerants that fall under (slightly flammable). In addition, R32 is classified into Subclass 2L (slightly flammable) in both of the above standards.

The air conditioner 100 is a so-called separate type refrigerating device. As shown in FIG. 1, the air conditioner 100 mainly includes an outdoor unit 20, an indoor unit 60, a gas-side refrigerant connecting pipe 82 and a liquid-side refrigerant connecting pipe 84 connecting 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 to each other via the gas-side refrigerant connecting pipe 82 and the liquid-side refrigerant connecting pipe 84, so that the compressor 22 and the outdoor heat exchange of the outdoor unit 20 will be described later. A refrigerant circuit 10 having a vessel 26, an expansion mechanism 28, an 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 to cool or heat the air-conditioned space in which the indoor unit 60 is arranged. The gas-side refrigerant connecting pipe 82 and the liquid-side refrigerant connecting pipe 84 are refrigerant pipes to be constructed locally when the outdoor unit 20 and the indoor unit 60 are installed.

(2) Detailed explanation The indoor unit 60 and the outdoor unit 20 of the air conditioner 100 will be described in detail.

(2-1) Indoor unit The indoor unit 60 is installed in the room (air-conditioned space) of the air-conditioning device 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-mounted type or a floor-standing type 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 the gas side refrigerant connecting pipe 82 via the gas side pipe 66. The liquid side of the indoor heat exchanger 62 is connected to the liquid side refrigerant connecting pipe 84 via the liquid side pipe 68. The indoor heat exchanger 62 functions as a cooler (evaporator that evaporates the refrigerant flowing inside) that cools the indoor air during the cooling operation. The indoor heat exchanger 62 functions as a heater (a condenser that condenses the refrigerant flowing inside) that heats the indoor air during the heating operation.

The indoor fan 64 is a fan for supplying indoor air to the indoor heat exchanger 62 and blowing out the indoor air that has exchanged heat with the refrigerant in the indoor heat exchanger 62 into the room. The indoor fan 64 is, for example, a centrifugal fan.

The indoor control unit 61 functions as a 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 measured values from various sensors (not shown) included in the indoor unit 60. Further, 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, which will be described later, via the transmission line 70a (see FIG. 1). The 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 will be described with reference to the drawings. 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 where the top plate 54 and the side plates (first member 51, right front plate 52, and right rear plate 53) of the housing 50, which will be described later, are removed. FIG. 4 is a schematic plan view of the bottom plate member 55 of the housing 50 of the outdoor unit 20. FIG. 5 is a schematic rear view of the outdoor unit 20 with the top plate 54 and the side plates removed.

In the following description, expressions such as "top", "bottom", "left", "right", "front (front)", and "rear (back)" may be used. Unless otherwise specified, these directions indicate the directions indicated by the arrows in FIGS. 2 to 5.

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. , A heater member 90, and an outdoor control unit 21 (see FIGS. 1 to 3).

(2-2-1) Connection by piping of constituent equipment With reference 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 closing valve 34, and The connection by piping of the constituent equipment of the outdoor unit 20 including the liquid side closing valve 36 will be described.

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 closing 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. It accommodates various configurations of the outdoor unit 20 such as the control unit 21.

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) arranged on the left front side of the outdoor unit 20 and a left side plate (not shown) arranged on the left side of the outdoor unit 20 are integrally formed. Is. A circular outlet (not shown) is formed on the front plate 51a. A ring-shaped bell mouth (not shown) is attached to the air outlet along its peripheral edge. When the outdoor fan 32 is driven, outdoor air is sucked in from the back side and the 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 the arrow indicating the airflow inside). A protective grill 57 is attached to the front plate 51a of the housing 50 in order to prevent external contact with the propeller of the outdoor fan 32, which will be described later (see FIG. 2). The protective grill 57 covers the outlet of the front plate 51a. The protective grill 57 is formed with a plurality of openings for blowing out air.

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

(2--2-2-1) Bottom plate member The bottom plate member 55 is a member constituting the bottom portion of the housing 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. A compressor 22, an outdoor heat exchanger 26, a support base 32a for supporting the outdoor fan 32, and the like are placed on the bottom plate member 55. Further, a heater member 90 is attached to the bottom plate member 55.

The bottom plate member 55 has a substantially rectangular bottom plate portion 551 (see FIG. 4) constituting the lower surface of the housing 50, and a wall portion 556 (see FIG. 5) provided on the peripheral edge of the bottom plate portion 551.

In the present embodiment, the wall portion 556 is provided so as to surround the peripheral edge of the bottom plate portion 551. The wall portion 556 extends vertically upward from the peripheral edge 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 fastening members such as screws.

A water guide groove 552 is formed in the bottom plate portion 551. The headrace groove 552 contains the rain blown into the outdoor unit 20, the water melted by the snow blown into the outdoor unit 20, the dew condensation water, and the water melted by the frost adhering to the outdoor heat exchanger 26 in the housing 50. It is a groove for discharging to the outside. The water guide groove 552 is formed so as to be recessed downward in the bottom plate portion 551.

The position where the headrace groove 552 is formed (the path of the headrace groove 552) will be described with reference to FIGS. 3 and 4.

The water guide groove 552 extends from the central portion of the bottom plate member 55 in the front-rear direction to the vicinity of the right rear corner portion of the bottom plate member 55 in the vicinity of the right end portion of the bottom plate member 55 along the right end portion of the bottom plate member 55. Further, the water guide groove 552 extends from the vicinity of the right rear corner portion of the bottom plate member 55 to the vicinity of the left rear corner portion along the rear end portion of the bottom plate member 55 in the vicinity of the rear end portion of the bottom plate member 55. Further, 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 portion of the bottom plate member 55 to the front, and the central portion (outdoor) of the bottom plate member 55 in the front-rear direction. (Near the left front end of the heat exchanger 26). Further, the water guide groove 552 extends from the vicinity of the left front end portion 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 extending along the rear end portion near the rear end portion of the bottom plate member 55 and a portion extending along the left end portion near the left end portion of the bottom plate member 55) is outdoor heat. It is formed below the exchanger 26.

A plurality of downwardly recessed recesses 554 and 555 are formed in the water guide groove 552 (see FIG. 4). In the state where the outdoor unit 20 is installed, the bottom surface of the recess 555 of 1 has a lower height position than the bottom surface of the other recesses 554. Further, in the state where the outdoor unit 20 is installed, the bottom surface of the recess 555 has the lowest height position among the bottom surface 552B of the water guide groove 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 headrace groove 552 is referred to as the lowermost bottom portion 552BL of the headrace groove. A drain hole 555a for draining the water flowing through the headrace groove 552 to the outside of the housing 50 is formed on the bottom surface of the recess 555, that is, the lowermost portion 552BL of the headrace groove (see FIG. 4). Further, a drain hole 554a for draining 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 headrace groove 552 is sloped along the headrace groove 552 so as to gradually decrease from the end of the headrace groove 552 toward the recess 555 in order to promote the discharge of water. That is, the headrace groove 552 is sloped so as to gradually decrease 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 be gradually lowered toward the recess 555. Note that FIG. 5 is an exaggerated drawing of the gradient of the headrace groove 552 for the sake of explanation, and does not represent the actual slope of the headrace groove 552.

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

A part of the heater member 90 mounted on the bottom plate member 55 is arranged below the outdoor heat exchanger 26 (see FIG. 3). The heater member 90 is arranged below the outdoor heat exchanger 26 over almost the entire area from the right rear end portion to the left front end portion of the outdoor heat exchanger along the extending direction of the outdoor heat exchanger 26. Is preferable. In the present embodiment, the heater member 90 is arranged in the headrace groove 552 below the outdoor heat exchanger 26 (see FIG. 3). In the present embodiment, the heater member 90 arranged below the outdoor heat exchanger 26 is entirely arranged in the water guide groove 552, but the present invention is not limited to this. For example, a part of the heater member 90 arranged below the outdoor heat exchanger 26 may be arranged outside the headrace groove 552. However, in order to prevent freezing of water below the outdoor heat exchanger 26 and further 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 is used. It is preferable that the entire portion arranged below the water guide groove 552 is arranged in the water guide groove 552.

Further, a part of the heater member 90 mounted on the bottom plate member 55 is arranged in a water guide groove 552 extending from the vicinity of the left front end portion 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 contact with the bottom surface 552B of the headrace groove 552 or is arranged in the vicinity of the bottom surface 552B of the headrace groove 552, particularly in the vicinity of the fixing member 92. However, since the headrace groove 552 is provided with a gradient, at least a part of the heater member 90 is arranged in the headrace groove 552 in a state where it does not come into contact with the bottom surface 552B of the headrace groove 552. In particular, since the bottom surface of the recesses 554 and 555 of the bottom surface 552B of the water guide groove 552 is recessed below the bottom surface 552B around the recesses 554 and 555, the bottom surface of the recesses 554 and 555 does not come into contact with the heater member 90. That is, the lowermost portion 552BL (bottom surface of the recess 555) of the water guide groove having the lowest height position among 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 through the suction pipe 41, and discharges the high-pressure refrigerant in the refrigeration cycle through the discharge pipe 42. The compressor 22 is, for example, a positive displacement compressor. The compressor 22 is, for example, an inverter type compressor capable of controlling 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 switching between the cooling operation and the heating operation of the air conditioner 100. During the cooling operation, the four-way switching valve 24 connects the discharge pipe 42 and the first gas side pipe 43, and also 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 switching valve 24 connects the discharge pipe 42 and the second gas side pipe 45, and also 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 to adjust the pressure and flow rate of the refrigerant. The expansion mechanism 28 is, for example, an electric valve whose opening degree can be adjusted.

(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 mounted on the bottom plate member 55 of the housing 50. The outdoor fan 32 is supported by a support base 32a 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 to the outside of the housing 50 from 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 shown by the arrow 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 the outdoor air and the 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 during the cooling operation and condenses the refrigerant flowing inside. The outdoor heat exchanger 26 functions as an evaporator that absorbs heat from the outdoor air into the refrigerant and evaporates the refrigerant flowing inside during the heating operation.

The outdoor heat exchanger 26 extends to the left along the back side of the housing 50 from the vicinity of the rear end of the partition plate 56, changes its direction near the left rear corner of the housing 50, and changes the direction of the housing 50. Extends forward along the left plate of the (see 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 the 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 portion 558 are not limited, the support portion 558 is located in the water guide groove 552, near the right rear end of the outdoor heat exchanger 26, and to the left rear of the outdoor heat exchanger 26. It is provided at three locations 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 extending in the left-right direction on the back surface side of the bottom plate member 55 of the outdoor heat exchanger 26 is arranged about 10 mm in front of the wall portion 556 on the back surface side of the bottom plate member 55. For example, the portion of the outdoor heat exchanger 26 extending in the left-right direction on the back surface side of the bottom plate member 55 is preferably arranged about 8 to 15 mm in front of the wall portion 556 on the back surface side of the bottom plate member 55.

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

The outdoor heat exchanger 26 is housing 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 headrace groove 552 formed below the outdoor heat exchanger 26 is 10 mm or more. It is installed within 50. In the present embodiment, due to the gradient of the headrace groove 552, the gap between the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the headrace groove 552 is minimized on the right rear side of the outdoor heat exchanger 26. Near the end of the outdoor heat exchanger 26, or near 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 headrace 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 headrace 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 left front end of. 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 headrace groove 552 is preferably in the range of 10 mm to 20 mm. When the minimum value Lmin is in the range of 10 mm to 20 mm, the bottom surface 552B of the headrace 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. Air easily flows between the heater member 90 and the lower end 26a of the outdoor heat exchanger 26 provided in the vicinity of the heater member 90. 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 headrace groove 552 and the lower end 26a of the outdoor heat exchanger 26 and becoming high in 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 during the operation of the air conditioner 100. , It is possible to prevent the air 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 higher than that of air, the refrigerant tends to accumulate in a low place. Specifically, among the headrace grooves 552 formed so as to be recessed downward in the bottom plate portion 551 of the bottom plate member 55, the refrigerant is particularly likely to accumulate in the lowest headrace groove bottom 552BL. Therefore, the distance between the lowermost portion 552BL of the water guide groove of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26 is preferably 12 mm or more. That is, the maximum value Lmax (see FIG. 5) of the gap between the lowermost portion 552BL of the water guide groove of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26 is preferably 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 lowermost portion 552BL of the water guide groove of the bottom plate member 55 and the lower end 26a of the outdoor heat exchanger 26, and the lowermost part of the water guide groove is generated. It is possible to prevent the refrigerant from accumulating in the 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, it is preferable that the lower end 26a of the outdoor heat exchanger 26 is located lower than the upper end 556a of the wall portion 556. With such a configuration, when the outdoor fan 32 is operated, it is possible to bypass the outdoor heat exchanger 26 and prevent excessive air from passing under the outdoor heat exchanger 26.

(2-2-9) Gas-side closing valve The gas-side closing valve 34 is connected to the gas-side refrigerant connecting pipe 82 and the second gas-side pipe 45, and is connected to the gas-side refrigerant connecting pipe 82 and the second gas-side pipe 45. It is a valve that switches between communication and non-communication.

When the air conditioner 100 is in operation, the gas side closing valve 34 is opened, and the second gas side pipe 45 and the gas side refrigerant connecting pipe 82 communicate with each other. During operation of the air conditioner 100, mainly the gas phase refrigerant flows through the gas side closing valve 34.

(2-2-10) Liquid-side closing valve In the liquid-side closing valve 36, the liquid-side refrigerant connecting pipe 84 and the liquid-side piping 44 are connected, and the liquid-side refrigerant connecting pipe 84 and the liquid-side piping 44 are communicated / non-communicated. It is a valve that switches communication.

During operation of the air conditioner 100, the liquid side closing valve 36 is opened, and the liquid side pipe 44 and the liquid side refrigerant connecting pipe 84 communicate with each other. During operation of the air conditioner 100, the liquid phase refrigerant mainly flows through the liquid side closing 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, for example, a metal tubular member having a heating wire such as a nichrome wire built therein. The heater member 90 is provided in the vicinity of the lower end 26a 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, for example, according to the assumed usage conditions (outside air temperature, etc.).

The heater member 90 is arranged in a loop on the bottom plate portion 551 of the bottom plate member 55. The heater member 90 is from the vicinity of the right rear corner of the outdoor unit 20 to the vicinity of the right rear end of the outdoor heat exchanger 26 so as to roughly follow the outdoor heat exchanger 26, and is on the left front side of the outdoor heat exchanger 26. It extends to near the end (see FIG. 3). Then, the heater member 90 extends to the right from the vicinity of the left front end of the outdoor heat exchanger 26 to the vicinity of the partition plate 56, changes its direction, further extends rearward, changes its direction again, and extends to the right. Then, it returns 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 portion of the outdoor heat exchanger 26 to the vicinity of the partition plate 56. The portion of the heater member 90 extending in the front-rear direction in the vicinity of the partition plate 56 is arranged not in the water guide groove 552 of the bottom plate portion 551 of the bottom plate member 55 but at a position higher than the bottom surface 552B of the water guide groove 552.

The laying route of the heater member 90 shown here is an example, and the laying route of the heater member 90 is not limited to the disclosed form. However, it is preferable that the heater member 90 is provided at least in the vicinity of the lower end 26a of the outdoor heat exchanger 26. Further, in order to prevent water from freezing in the water guide groove 552, it is preferable that the heater member 90 is at least partially arranged in the water guide groove 552. In particular, the heater member 90 arranged below the outdoor heat exchanger 26 is preferably arranged in the headrace groove 552.

(2-2-12) Outdoor control unit The outdoor control unit 21 functions as a control unit 70 together with the indoor control unit 61 of the indoor unit 60 to control the operation of the air conditioner 100. In order to execute this function, the outdoor control unit 21 has various electric circuits, a microcomputer, and a memory in which a program executed by the microcomputer is stored. The outdoor control unit 21 receives measured values from various sensors (not shown) included in the outdoor unit 20. Further, 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 operations during the cooling operation and the heating operation. The control mode of the air conditioner 100 is an example, and does not limit the operation mode of the air conditioner 100.

During the cooling operation, the control unit 70 operates the compressor 22 in a state where the four-way switching valve 24 is switched to the state shown 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 shown 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. Further, when the temperature of the outdoor heat exchanger 26 becomes equal to or lower than the predetermined temperature during the heating operation, the defrost operation is performed to remove the frost adhering 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 during the cooling operation in order to remove the frost adhering to the outdoor heat exchanger 26. ..

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

Further, the control unit 70 intermittently shortens the outdoor fan 32 in order to prevent the detection temperature of the sensor (not shown) that detects the outdoor temperature from deviating from the actual outdoor temperature when the air conditioner 100 is stopped. Perform intermittent fan operation 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 thereof. It is easy to prevent the refrigerant from accumulating in the space between the lower end 26a and the lower end 26a and having a high concentration.

(3) Features (3-1)
The air conditioner 100 of the present 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 has a bottom plate member 55 on which the outdoor heat exchanger 26 is placed, and houses 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 26a of the outdoor heat exchanger 26, and is mounted on the bottom plate member 55. The bottom plate member 55 is formed with a water guide groove 552 below the outdoor heat exchanger 26. The minimum value Lmin of the distance between the bottom surface 552B of the headrace 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 guided to the outdoor heat exchanger by bypassing the air between the bottom plate member and the lower end of the outdoor heat exchanger during the operation of the refrigerating device. It is taken as small as possible to prevent the amount of air from decreasing and reducing efficiency. Therefore, in the conventional refrigerating apparatus, it is difficult for air to flow in the water guide groove formed in the bottom plate member even while the outdoor fan is in operation. Therefore, when the refrigerant leaks in the housing, the refrigerant tends to accumulate in the headrace 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, 10 mm or more. Taken by value. Therefore, even if the refrigerant leaks in the housing 50, the refrigerant accumulates in the space between the bottom surface 552B of the headrace groove 552 and the lower end 26a of the outdoor heat exchanger 26 provided in the vicinity of the heater member 90, resulting in a high concentration. It can be prevented from becoming. On the other hand, since the minimum distance between the bottom surface 552B of the headrace 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 to exchange outdoor heat. It is possible to prevent excessive passage of air below the vessel 26.

(3-2)
In the air conditioner 100 of the present embodiment, the distance between the lowermost portion 552BL of the headrace groove, which is the lowest in the bottom surface 552B of the headrace groove 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 arranged at a distance of 12 mm or more from the lowermost portion of the headrace groove 552 where the refrigerant tends to collect. Therefore, even if the refrigerant leaks in the housing 50, it is possible to prevent the refrigerant from accumulating in the lowermost portion 552BL of the headrace groove and having a high concentration.

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

In the air conditioner 100 of the present embodiment, a drain hole 555a is formed in the lowermost portion 552BL of the headrace groove where the concentration of the refrigerant tends to increase when the refrigerant leaks. Therefore, the refrigerant can be discharged to the outside of the housing 50 from the drain hole 555a, and even if the refrigerant leaks inside the housing 50, it is prevented that the refrigerant accumulates in the lowermost portion 552BL of the headrace groove and becomes high concentration. Easy to be done.

(3-4)
In the air conditioner 100 of the present embodiment, the heater member 90 is at least partially arranged in the headrace groove 552. The lowermost portion 552BL of the headrace groove is not in contact with the heater member 90.

In the air conditioner 100 of the present embodiment, the heater member 90 is arranged away from the lowermost portion 552BL of the headrace groove where the concentration of the refrigerant tends to be high. Therefore, even if the refrigerant is present in the lowermost portion 552BL of the headrace groove, it is possible to prevent an ignition accident.

(3-5)
In the air conditioner 100 of the present embodiment, the bottom plate member 55 has a wall portion 556 provided on the peripheral edge. The lower end 26a of the outdoor heat exchanger 26 is located lower than the upper end 556a 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 arranged below the upper end 556a of the wall portion 556 provided on the peripheral edge. Therefore, while ensuring the air flow by separating the lower end 26a of the outdoor heat exchanger 26 and the bottom surface 552B of the headrace groove 552, the outdoor heat exchanger 26 is bypassed during the operation of the outdoor fan 32, and the outdoor heat exchanger is used. It is possible to prevent the air from passing excessively below the 26.

(4) Modification Example A modification of the air conditioner 100 according to the above embodiment is shown. The modified examples may be appropriately combined as long as they do 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 headrace 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. With this formation, the heater member 90 is less likely to come into contact with the bottom surface 552B of the headrace groove 552, so that the refrigerant having a higher density than air leaks in the outdoor unit 20 and the refrigerant is near the bottom surface 552B of the headrace 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 above embodiment, it is preferable that the headrace groove 552 is provided with recesses 554 and 555, and the recesses 554 and 555 are provided with drain holes 554a and 555a, but the present invention is not limited thereto. ..

For example, a drain hole may be directly formed in the headrace groove 552 (without providing recesses 554 and 555). When the headrace groove 552 is inclined as in the above embodiment, the headrace groove having the lowest height position among the bottom surface 552B of the headrace groove 552 even when the recesses 554 and 555 are not provided. It is possible to prevent the heater member 90 from coming into contact with the lowermost portion.

(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 the present invention is not limited to this. For example, the wall portion 556 may not be provided in a part of the peripheral edge of the bottom plate member 55. Further, the bottom plate member 55 does not have to have the wall portion 556.

However, since the bottom plate member 55 has a 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 to secure the air flow and to keep the air flowing outdoors. When the fan 32 is operated, the outdoor heat exchanger 26 can be bypassed to prevent excessive air from passing under the outdoor heat exchanger 26.

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

INDUSTRIAL APPLICABILITY The present invention includes a heater member attached to a bottom plate member of a housing for accommodating an outdoor heat exchanger, and can be widely applied to a refrigerating apparatus using a flammable refrigerant, which is useful.

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 Refrigerator 552 Water guide groove 552B Bottom 552BL Water guide groove bottom 555a Drain hole 556 Wall 556a Top (top of wall)
Lmin minimum value

Japanese Unexamined Patent Publication No. 2015-555455

Claims (4)

A refrigeration system that uses a refrigerant heavier than flammable air.
An outdoor heat exchanger (26) in which heat is exchanged between the refrigerant and the outside air.
An outdoor fan (32) that supplies 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 accommodating the outdoor heat exchanger and the outdoor fan.
An electric heater member (90) provided at least in the vicinity of the lower end (26a) of the outdoor heat exchanger and mounted on the bottom plate member, and
Equipped with
A water guide groove (552) is formed below the outdoor heat exchanger in the bottom plate member.
The minimum value (Lmin) of the distance between the bottom surface (552B) of the headrace groove and the lower end of the outdoor heat exchanger is in the range of 10 mm to 20 mm.
The bottom plate member has a wall portion (556) provided on the peripheral edge thereof.
The lower end of the outdoor heat exchanger is located lower than the upper end (556a) of the wall portion.
Refrigerator (100). The distance between the lowermost portion of the headrace groove (552BL), which has the lowest height of the bottom surface of the headrace groove, and the lower end of the outdoor heat exchanger is 12 mm or more.
The refrigerating apparatus according to claim 1. A drain hole (555a) is formed at the bottom of the headrace groove.
The refrigerating apparatus according to claim 2. The electric heater member is at least partially arranged in the headrace groove.
The lowermost portion of the water guide groove is not in contact with the electric heater member.
The refrigerating apparatus according to claim 2 or 3.

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