CN111801533A

CN111801533A - Indoor unit of air conditioner and air conditioner provided with same

Info

Publication number: CN111801533A
Application number: CN201880089448.1A
Authority: CN
Inventors: 渡部和树; 高木昌彦; 古田辰夫; 浜田浩太
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2018-02-20
Filing date: 2018-02-20
Publication date: 2020-10-20
Also published as: EP3757475B1; WO2019162993A1; JPWO2019162993A1; JP6949194B2; EP3757475A1; AU2018410266B2; US20210041114A1; AU2018410266A1; EP3757475A4

Abstract

An indoor unit of an air conditioner is provided with: a suction grill having a suction port through which gas flows; a decorative panel, which is provided with a suction grille and is provided with an air outlet for air to flow out; a casing to which a decorative panel is attached and which forms an air passage between the suction port and the discharge port; a blower arranged in the casing so as to face the suction grille, the blower causing gas to flow in from the suction port and causing gas to flow out from the discharge port; a heat exchanger disposed in the casing in an air passage between the blower and the outlet port, the heat exchanger exchanging heat between the refrigerant flowing inside and the gas; and a refrigerant detection sensor that detects leakage of the refrigerant, wherein the suction grill is disposed below the heat exchanger, and the refrigerant detection sensor is disposed below the heat exchanger and between the suction grill and the blower.

Description

Indoor unit of air conditioner and air conditioner provided with same

Technical Field

The present invention relates to an indoor unit of an air conditioner including a gas sensor for detecting refrigerant leakage, and an air conditioner including the indoor unit.

Background

Among refrigerants used in conventional air conditioners, there are refrigerants having flammability. Therefore, when a flammable refrigerant leaks from an indoor unit of an air conditioner or the like, if the leaked refrigerant exceeds a certain concentration, there is a risk of ignition of the refrigerant. Therefore, for example, in order to detect leakage of a flammable refrigerant such as R32 refrigerant, an indoor unit of an air conditioner has been proposed in which temperature sensors are provided at a plurality of locations (see, for example, patent document 1). The indoor unit of the air conditioner of patent document 1 detects whether or not the refrigerant leaks from the difference between the air temperature and the refrigerant temperature in the pipe.

Patent document 1: japanese patent laid-open publication No. 2016-

The temperature of the refrigerant flowing through the indoor unit of the air conditioner changes significantly depending on various operation states such as cooling, heating, and defrosting operation of the outdoor unit. Therefore, in the conventional technique of detecting and reporting a difference between the indoor air and the refrigerant temperature in the pipe, for example, a difference in temperature occurs between the refrigerant temperature that changes during the defrosting operation of the outdoor unit and the indoor temperature that does not change, and therefore there is a possibility that erroneous detection may occur.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and provides an indoor unit of an air conditioner and an air conditioner provided with the indoor unit, in which the detection accuracy of a refrigerant after the refrigerant leaks from the indoor unit of the air conditioner is improved.

An indoor unit of an air conditioner of the present invention includes: a suction grill having a suction port through which gas flows; a decorative panel, which is provided with a suction grille and is provided with an air outlet for air to flow out; a casing to which a decorative panel is attached and which forms an air passage between the suction port and the discharge port; a blower arranged in the casing so as to face the suction grille, the blower causing gas to flow in from the suction port and causing gas to flow out from the discharge port; a heat exchanger disposed in the casing in an air passage between the blower and the outlet port, the heat exchanger exchanging heat between the refrigerant flowing inside and the gas; and a refrigerant detection sensor that detects leakage of the refrigerant, wherein the suction grill is disposed below the heat exchanger, and the refrigerant detection sensor is disposed below the heat exchanger and between the suction grill and the blower.

In the indoor unit of an air conditioner according to the present invention, the suction grill is disposed below the heat exchanger, and the refrigerant detection sensor is disposed below the heat exchanger and between the suction grill and the blower. Therefore, even when the refrigerant leaking from the inside of the casing is diluted and the refrigerant leakage cannot be detected instantaneously during the operation of the blower, the refrigerant contained in the gas flowing out from the discharge port and flowing into the suction port can be detected by the refrigerant detection sensor before the refrigerant concentration in the room reaches the flammable region. In addition, since the refrigerant is retained in the bottom portion of the casing when the blower is stopped, the refrigerant detection sensor can detect the refrigerant leakage. As a result, the detection accuracy of the refrigerant after the refrigerant leaks from the indoor unit of the air conditioner can be improved.

Drawings

Fig. 1 is a bottom view of an indoor unit of an air conditioner according to embodiment 1 of the present invention.

Fig. 2 is a sectional view taken along line a-a of the indoor unit of fig. 1.

Fig. 3 is a bottom view of the indoor unit of fig. 1 with a suction grill removed.

Fig. 4 is a front view of a sensor holder provided in an indoor unit of an air conditioner according to embodiment 1 of the present invention.

Fig. 5 is a right side view of the sensor holder of fig. 4.

Fig. 6 is a left side view of the sensor holder of fig. 4.

Fig. 7 is an exploded perspective view of the sensor holder of fig. 4.

Fig. 8 is an exploded perspective view of the sensor holder of fig. 4 as viewed from another direction.

Fig. 9 is an exploded perspective view of a sensor holder provided in an indoor unit of an air conditioner according to embodiment 2 of the present invention.

Fig. 10 is an exploded perspective view of a sensor holder provided in an indoor unit of an air conditioner according to embodiment 2 of the present invention, as viewed from another direction.

Fig. 11 is a schematic diagram showing a configuration of an air conditioner according to embodiment 3 of the present invention.

Detailed Description

An indoor unit 100 of an air conditioner and an air conditioner 200 including the indoor unit 100 according to an embodiment of the present invention will be described below with reference to the drawings and the like. In the following drawings including fig. 1, the relative dimensional relationships and shapes of the respective constituent members may differ from those of actual members. In the drawings, the same or corresponding components are denoted by the same reference numerals and are common throughout the specification. Also, terms indicating directions (for example, "upper", "lower", "right", "left", "front", "rear", and the like) are used as appropriate for easy understanding, but their expressions are described for convenience of description only, and do not limit the arrangement and orientation of the devices or components.

Embodiment 1.

[ indoor Unit 100]

Fig. 1 is a bottom view of an indoor unit 100 of an air conditioner according to embodiment 1 of the present invention. Fig. 2 is a sectional view taken along line a-a of the indoor unit 100 of fig. 1. The X axis shown in the following drawings including fig. 1 indicates the left-right width direction of the indoor unit 100, the Y axis indicates the front-rear direction of the indoor unit 100, and the Z axis indicates the up-down direction of the indoor unit 100. More specifically, the indoor unit 100 will be described with the X1 side being the left side, the X2 side being the right side, the Y1 side being the front side, the Y2 side being the rear side, the Z1 side being the upper side, and the Z2 side being the lower side on the X axis. In the description, the positional relationship (for example, the vertical relationship) between the respective components is basically a state in which the indoor unit 100 is installed so as to be usable. In the present embodiment, a four-sided box-type indoor unit 100 that is of a ceiling-embedded type and that can be embedded in an indoor ceiling and forms air outlets 13c in four directions will be described. The indoor unit 100 is connected to an outdoor unit by a refrigerant pipe, and circulates a refrigerant to form a refrigerant circuit for performing refrigeration, air conditioning, and the like. The refrigerant used in the indoor heat exchanger 30 of the indoor unit 100 has a density higher than that of air. However, the refrigerant used in the indoor heat exchanger 30 of the indoor unit 100 is not limited to a refrigerant having a density greater than that of air, and a refrigerant having a density equal to or less than that of air may be used.

The indoor unit 100 supplies conditioned air to an air-conditioned space such as a room by using a refrigeration cycle in which a refrigerant circulates. First, an external configuration of the indoor unit 100 will be described with reference to fig. 1 and 2. As shown in fig. 2, the indoor unit 100 includes a casing 10 that accommodates a blower 20, an indoor heat exchanger 30, and the like therein. The casing 10 has a ceiling 11 constituting a ceiling wall and side plates 12 constituting four side walls, front, rear, right and left, and is opened to the lower side (Z2 side) of the room. A decorative panel 13 having a substantially rectangular shape in plan view is attached to the opening portion of the casing 10.

The decorative panel 13 is a plate-like member, and has one surface facing an attachment portion such as a ceiling or a wall, and the other surface facing an indoor space which is a space to be air-conditioned. As shown in fig. 1 and 2, an opening 13a, which is a through hole, is formed near the center of the decorative panel 13, and the suction grill 14 is attached to the opening 13 a. A suction port 14a is formed in the suction grill 14, and the suction port 14a allows air to flow into the casing 10 from the room serving as the space to be air-conditioned. A filter (not shown) is disposed on the casing 10 side of the suction grill 14, and removes dust from the air passing through the suction grill 14. A blowout port 13c through which air flows out is formed in the decorative panel 13 between the outer edge portion 13b of the decorative panel 13 and the inner edge portion forming the opening 13 a. The air outlets 13c are formed along each of the four sides of the decorative panel 13. Each of the air outlets 13c is provided with a blade 15 that changes the wind direction. Casing 10 forms an air passage inside casing 10 between suction port 14a and discharge port 13 c.

Fig. 3 is a bottom view of the indoor unit 100 of fig. 1 with the suction grill 14 removed. Next, the internal structure of the indoor unit 100 will be described with reference to fig. 2 and 3. The indoor unit 100 includes a fan 20, and the fan 20 causes air in the room to flow in through the inlet 14a and causes air to flow out through the outlet 13c into the room. The blower 20 is disposed in the casing 10 so as to face the suction grill 14. The blower 20 is disposed in the casing 10 such that the rotation axis thereof faces the plumb direction (Z-axis direction).

The indoor unit 100 includes an indoor heat exchanger 30, and the indoor heat exchanger 30 is disposed in the casing 10 in an air passage between the blower 20 and the outlet 13c, and exchanges heat between the refrigerant flowing inside the indoor heat exchanger 30 and the air flowing in the air passage. The indoor heat exchanger 30 is disposed in the casing 10 in an air passage between the blower 20 and the outlet 13 c. The indoor heat exchanger 30 generates air-conditioning air by exchanging heat between the refrigerant flowing inside and the indoor air. The indoor heat exchanger 30 is, for example, a fin-tube type heat exchanger, and is disposed so as to surround the blower 20 on the downstream side of the blower 20 in the flow of the gas. For example, when the indoor unit 100 of the present embodiment is applied to the air conditioner 200 described later, the indoor heat exchanger 30 functions as an evaporator during the cooling operation and functions as a condenser during the heating operation. The blower 20 and the indoor heat exchanger 30 are disposed on the downstream side of the air from the air inlet 14a and on the upstream side of the air from the air outlet 13c in the casing 10. In the indoor unit 100, the blower 20 is disposed above the suction grill 14, and the indoor heat exchanger 30 is disposed in the radial direction of the blower 20. The suction grill 14 of the indoor unit 100 is disposed below the indoor heat exchanger 30.

Further, the indoor unit 100 has a socket 16. As shown in fig. 2 and 3, the mouthpiece 16 is provided upstream of the blower 20 on the air inflow side of the indoor unit 100. The mouthpiece 16 rectifies the gas flowing from the suction port 14a of the suction grill 14 and sends the gas to the blower 20.

The indoor unit 100 further includes an electrical component box 40 in the casing 10 between the inlet 16 and the suction grill 14. The electrical component box 40 is a box having devices such as a controller for controlling the indoor unit 100 therein. The devices in the electrical component box 40 supply power to the devices of the indoor unit 100 and perform signal transmission/reception (communication). The control unit 80 is disposed in the electrical component box 40, and the control unit 80 processes signals from the refrigerant detection sensor 50 and the temperature sensor 70, which will be described later. The control Unit 80 includes, for example, a storage Unit for storing a program and a CPU (central processing Unit) for executing processing in accordance with the program. The control unit 80 may be provided in the sensor holder 60 described later. The electric component box 40 is formed in a substantially rectangular parallelepiped shape. The electrical component box 40 is disposed in the opening 13a formed in the decorative panel 13 when viewed from the ceiling in a plan view from the indoor side, and the longitudinal direction of the electrical component box 40 is disposed along the edge of the decorative panel 13 forming one side of the opening 13 a. The electric component box 40 is fixed in the housing 10 by a fixing member such as a screw.

The indoor unit 100 further includes a refrigerant detection sensor 50 that detects leakage of the refrigerant. The refrigerant detection sensor 50 is formed in a cylindrical shape, for example. The refrigerant detection sensor 50 mainly uses a semiconductor for the gas sensing element and generates an output according to the oxygen concentration, for example, detects a resistance value change generated when the metal oxide semiconductor is in contact with a gas contained in the air as the gas concentration. The refrigerant detection sensor 50 may be driven by power supplied from the indoor unit 100 or by power supplied from a local external power supply in which the indoor unit 100 is installed. When the refrigerant detection sensor 50 is not driven by power supplied from the indoor unit 100 or an external power supply, for example, a battery may be incorporated in the electric component box 40 or the sensor holder 60.

The refrigerant detection sensor 50 is disposed below the indoor heat exchanger 30 and between the suction grill 14 and the blower 20. That is, as shown in fig. 2, the refrigerant detection sensor 50 is disposed at the bottom of the indoor unit 100 located below the socket 16 and the indoor heat exchanger 30. Further, refrigerant detection sensor 50 is disposed in the vicinity of suction port 14a formed in suction grill 14. The reason why the refrigerant detection sensor 50 is disposed at the bottom of the indoor unit 100 located below the socket 16 and the indoor heat exchanger 30 is that the blade 15 provided at the outlet 13c is closed when the indoor unit 100 is stopped, and therefore the refrigerant is less likely to leak from the inside of the casing 10. Therefore, it is desirable that the casing 10 be filled with the refrigerant and the refrigerant detection sensor 50 be disposed at the bottom of the indoor unit 100 where the leaked refrigerant accumulates. The reason why the refrigerant detection sensor 50 is disposed in the vicinity of the suction port 14a formed in the suction grill 14 is that the refrigerant accumulated in the bottom of the indoor unit 100 is diluted by the air flowing in when the blower 20 is operated. In addition, the refrigerant detection sensor 50 is characterized by a sensor that uses a semiconductor for the gas sensing element and generates an output according to the oxygen concentration, and therefore detection of the leaked refrigerant becomes difficult. Therefore, when the blower 20 is operated, the refrigerant is discharged from the discharge port 13c into the room, and therefore the refrigerant concentration in the room becomes high, and it is desirable to dispose the refrigerant near the suction port 14a in the indoor space so as to be able to detect the refrigerant when it is sucked from the suction port 14 a. The vicinity of the suction port 14a is a space between the blower 20 and the suction grill 14, more specifically, between the mouthpiece 16 and the suction grill 14, in a direction (Z-axis direction) perpendicular to a mounted portion such as a ceiling. The vicinity of the suction port 14a is a position formed in the opening 13a of the decorative panel 13 when viewed from the ceiling in a plan view from the indoor side. The refrigerant detection sensor 50 is disposed in the sensor holder 60. The refrigerant detection sensor 50 is excellent in maintainability because the operation of replacing the sensor can be performed by removing the screw of the electric component box 40 to which the sensor holder 60 is attached and removing the electric component box 40 from the housing 10.

Fig. 4 is a front view of a sensor holder 60 provided in an indoor unit 100 of an air conditioner according to embodiment 1 of the present invention. Fig. 5 is a right side view of the sensor holder 60 of fig. 4. Fig. 6 is a left side view of the sensor holder 60 of fig. 4. Fig. 7 is an exploded perspective view of the sensor holder 60 of fig. 4. Fig. 8 is an exploded perspective view of the sensor holder 60 of fig. 4 as viewed from another direction. Next, the sensor holder 60 will be described with reference to fig. 4 to 8. The X, Y, and Z axes shown in fig. 4 to 6 are axial directions after the sensor holder 60 is installed in the indoor unit 100. In the following description, in the sensor holder 60, a direction in which the first receiving portion 61 and the second receiving portion 62 are connected is referred to as a longitudinal direction (Y-axis direction), and a direction perpendicular to the bottom portion 61a and the bottom portion 62a formed in a plate shape is referred to as a height direction (X-axis direction). Further, a direction perpendicular to the longitudinal direction (Y-axis direction) and the vertical direction (X-axis direction) is referred to as a short-side direction (Z-axis direction).

The sensor holder 60 is a member for fixing the refrigerant detection sensor 50 and the temperature sensor 70 in the casing 10, and is a member for protecting the refrigerant detection sensor 50 and the temperature sensor 70 from dust and the like. Further, the sensor holder 60 blocks contact of the human finger with the detection portion 51 so that the human finger does not touch the detection portion 51 at the time of energization when the detection portion 51 of the refrigerant detection sensor 50 is made of metal. The sensor holder 60 is a resin member such as PS (polystyrene), for example. A refrigerant detection sensor 50 and a temperature sensor 70 are provided in the sensor holder 60. The refrigerant detecting sensor 50 and the temperature sensor 70 can be protected by one cover by being integrated in one sensor holder 60. Further, a cover of the maintenance member of the refrigerant detection sensor 50 can be shared with the temperature sensor 70. The sensor holder 60 is formed in a box shape. As shown in fig. 2 and 3, the sensor holder 60 is fixed so as to be inserted into a side wall 40a of the electrical component box 40 facing the air passage between the suction port 14a and the blower 20, and the refrigerant detection sensor 50 and the temperature sensor 70 are disposed so as to protrude from the electrical component box 40. The sensor holder 60 is disposed in the opening 13a formed in the decorative panel 13 when viewed from the ceiling in a plan view from the indoor side. The sensor holder 60 is disposed between the suction grill 14 and the blower 20, more specifically, between the suction grill 14 and the mouthpiece 16, in a direction (Z-axis direction) perpendicular to a mounted portion such as a ceiling. The sensor holder 60 is inserted into the electrical component box 40. The sensor holder 60 is inserted into the electric component box 40, and thus, the distance between the wires can be shortened without requiring the handling of the wires connected to the sensors. If the lead wire is provided in parallel with the power supply line or the like, noise may be added to the output signal of the refrigerant detection sensor 50. By directly attaching the sensor holder 60 to the electrical component box 40, the distance of the lead wire is shortened, and noise of the output signal of the refrigerant detection sensor 50 can be suppressed.

As shown in fig. 4, the sensor holder 60 has a first receiving portion 61 and a second receiving portion 62 in the longitudinal direction (Y-axis direction). As shown in fig. 8 and 9, the refrigerant detection sensor 50 is housed in the first housing portion 61, and the temperature sensor 70 is housed in the second housing portion 62. The temperature sensor 70 is, for example, a thermistor. As shown in fig. 4 to 9, the first receiving portion 61 and the second receiving portion 62 are each formed in a substantially rectangular parallelepiped shape, and the first receiving portion 61 and the second receiving portion 62 are formed integrally. The bottom portion 61a of the first receiving portion 61 and the bottom portion 62a of the second receiving portion 62 are integrally formed in a plate shape, and a space between the bottom portion 61a and the bottom portion 62a is formed in a flat shape on the outer peripheral surface. The second housing portion 62 has a larger size in the height direction (X-axis direction) than the first housing portion 61. The lateral side wall 61e, the bottom 61a, the top plate 61b, the lateral side wall 62e, and the bottom 62a of the first housing 61 are divided in the lateral direction (Z-axis direction). Therefore, the sensor holder 60 can be divided into two parts in the short direction (Z-axis direction) in a state where only the top plate 62b of the second housing portion 62 is connected.

A through hole 61d is formed from the top plate 61b to the upper end of the side wall 61c of the first receiving portion 61. The refrigerant detection sensor 50 detects the gas flowing into the first housing portion 61 from the through hole 61 d. The through hole 61d is formed in a slit shape. The through hole 61d is formed at an end portion opposite to the second housing portion 62 (Y1 side) in the longitudinal direction (Y axis direction) of the top plate 61 b. The through holes 61d are formed in both ends of the top plate 61b in the short direction (Z-axis direction). Further, a plurality of through holes 61d are formed in the longitudinal direction (Y-axis direction) of the first housing portion 61. The width between the walls 61f of the sensor holder 60 in which the plurality of through holes 61d are formed is smaller than the thickness of a human finger. Therefore, the through-hole 61d is formed in a size that cannot be penetrated by a human finger. The width of the opening of the through hole 61d is defined so that the detection portion 51 of the refrigerant detection sensor 50 is not touched by a bare hand. The sensor holder 60 is a resin member, and there is no problem even if touched by an operator. The plurality of through holes 61d are formed at positions facing the refrigerant detection sensor 50. More specifically, the through hole 61d is open only at a position where the cylindrical portion constituting the refrigerant detection sensor 50 can be seen. When the wind comes from the suction port 14a, the wind needs to pass around the cylindrical portion. However, if the wind from the inlet 14a is excessively taken in unnecessarily, the opening area is set to the minimum necessary because of the notification of noise and the like. As shown in fig. 7 and 8, the detection portion 51 of the refrigerant detection sensor 50 is disposed to face the top plate 61 b. As shown in fig. 2 and 3, when the sensor holder 60 is disposed in the casing 10, the detection portion 51 of the refrigerant detection sensor 50 is disposed in a direction perpendicular to the flow of the gas from the suction port 14a toward the blower 20, and is not opposed to the direction of the air sucked into the casing 10. The detection unit 51 of the refrigerant detection sensor 50 is not clogged by dust or the like contained in the gas sucked into the casing 10.

A through hole 62d is formed from the top plate 62b to the side wall 62c of the second receiving portion 62. The through hole 62d is formed in a slit shape. The through hole 62d is formed on the front end side from a central portion 62g in the height direction (X-axis direction) of the side wall 62c in the height direction (X-axis direction). A plurality of through holes 62d are formed along the longitudinal direction (Y-axis direction) of the top plate 62 b. The through holes 62d are formed in both ends of the top plate 62b in the short direction (Z-axis direction). The width between the walls 62f of the sensor holder 60 in which the plurality of through holes 62d are formed is smaller than the thickness of a human finger. Therefore, the through-hole 62d is formed in a size that cannot be penetrated by a human finger. The plurality of through holes 62d are formed at positions facing the temperature sensor 70. The temperature sensor 70 is disposed in the sensor holder 60, and detects the temperature of the gas flowing from the through hole 62d into the second housing portion 62 and the temperature of the gas flowing from the suction port 14 a.

The second housing portion 62 is formed with a substantially rectangular parallelepiped bulging portion 64b bulging in the height direction (X-axis direction) from the outer wall surface of the bottom portion 62 a. The sensor holder 60 is fixed to the electrical component box 40 as shown in fig. 3 by inserting the bulging portion 64b into the side wall 40a of the electrical component box 40. As shown in fig. 7 and 8, an opening 64b2 is formed in the distal end 64b1 of the bulge 64 b. The bulge portion 64b is formed with a through hole 64b3 that communicates the opening 64b2 with the internal space of the bulge portion 64 b. A cable for connecting the refrigerant detection sensor 50 to the control unit 80 housed in the electrical component box 40 or a cable for supplying power to the refrigerant detection sensor 50 is disposed in the through hole 64b 3.

Next, the operation of the indoor unit 100 will be described. In the indoor unit 100, when the fan 20 is driven, indoor air is sucked from the suction port 14a, cleaned by the filter, flows into the impeller of the fan 20 through the socket 16, and flows out to the outer peripheral side of the impeller from between the plurality of blades. The air flowing out of the impeller is cooled or heated by heat exchange with the refrigerant flowing through the interior of the indoor heat exchanger 30, turns into cold air or hot air, and is blown out into the room from the air outlet 13 c. At this time, when the refrigerant leaks, the refrigerant is blown out into the room from the outlet port 13c, and the blown-out refrigerant is sucked from the suction port 14 a. Further, the refrigerant detection sensor 50 detects the presence of the refrigerant after the refrigerant leaked into the room is sucked. In contrast, in the indoor unit 100, when the operation of the blower 20 is stopped, even if the refrigerant leaks from any of the pipes in the casing 10, the casing 10 is filled with the refrigerant, and the refrigerant detection sensor 50 disposed at the bottom of the indoor unit 100 where the leaked refrigerant accumulates detects the refrigerant.

As described above, in the indoor unit 100 of the air conditioner, the suction grill 14 is disposed below the indoor heat exchanger 30, and the refrigerant detection sensor 50 is disposed below the indoor heat exchanger 30 and between the suction grill 14 and the blower 20. Normally, when the blower 20 is operated, the refrigerant leaking from the inside of the casing 10 is diluted, and the refrigerant leakage cannot be detected instantaneously. However, in this case, the refrigerant contained in the gas flowing out from the outlet port 13c and flowing in from the inlet port 14a can be detected by the detection sensor 50 before the concentration of the refrigerant in the room reaches the flammable region. Further, when the blower 20 is stopped, the refrigerant stays at the bottom of the casing 10, and therefore the refrigerant detection sensor 50 can detect the refrigerant leakage. Therefore, the indoor unit 100 of the air conditioner can improve the detection accuracy of the refrigerant after the refrigerant leakage. As a result, the indoor unit 100 can realize a safe air conditioner in which the detection sensor 50 detects the leakage of the refrigerant without reaching the lower limit ignition density.

In the indoor unit 100 of the air conditioner, the detection portion 51 of the refrigerant detection sensor 50 is provided at right angles to the flow of the gas from the suction port 14a toward the blower 20. Therefore, the refrigerant detection sensor 50 is disposed in a direction not facing the direction of the air sucked into the casing 10. As a result, clogging of the detection portion 51 of the refrigerant detection sensor 50 due to dust and the like contained in the gas sucked into the casing 10 can be suppressed.

Further, the indoor unit 100 of the air conditioner includes a box-shaped sensor holder 60 for fixing the refrigerant detection sensor 50 in the casing 10, and the refrigerant detection sensor 50 is disposed in the sensor holder 60. Therefore, the refrigerant detection sensor 50 can be disposed below the indoor heat exchanger 30 in the casing 10 and between the suction grill 14 and the blower 20. In addition, the refrigerant detection sensor 50 can be protected from the accumulation of dust and the like. Further, when the detection portion 51 of the refrigerant detection sensor 50 is made of metal, the finger of the operator can be prevented from touching the detection portion 51 when the power is applied.

In the indoor unit 100 of the air conditioner, the sensor holder 60 is disposed between the suction grill 14 and the blower 20. Therefore, as described above, the refrigerant detection sensor 50 can protect it from dust or prevent contact with an operator, and the indoor unit 100 of the air conditioner can improve the detection accuracy of the refrigerant after the refrigerant leaks. The indoor unit 100 can realize a safe air conditioner in which the refrigerant detection sensor 50 detects the leakage of the refrigerant without reaching the lower limit ignition density.

The indoor unit 100 of the air conditioner includes an electrical component box 40 having a control device for controlling the indoor unit 100 of the air conditioner therein, and the sensor holder 60 is fixed to a side wall 40a of the electrical component box 40. The refrigerant detection sensor 50 is excellent in maintainability because the operation of replacing the sensor can be performed by removing the screw of the electric component box 40 to which the sensor holder 60 is attached and removing the electric component box 40 from the housing 10.

In the indoor unit 100 of an air conditioner, a plurality of through holes 61d are formed in the sensor holder 60 at positions facing the refrigerant detection sensor 50, and the width between the walls 61f of the sensor holder 60 in which the plurality of through holes 61d are formed is smaller than the thickness of a human finger. Therefore, when the detection portion 51 of the refrigerant detection sensor 50 is made of metal, the finger of the operator can be prevented from touching the detection portion 51 when the power is applied.

The indoor unit 100 of the air conditioner further includes a temperature sensor 70, the temperature sensor 70 detects the temperature of the gas flowing in from the inlet 14a, and the temperature sensor 70 is disposed in the sensor holder 60. Therefore, the indoor unit 100 of the air conditioner can measure the temperature, and for example, the accuracy of various measurements such as detection of refrigerant leakage can be further improved.

Embodiment 2.

Fig. 9 is an exploded perspective view of a sensor holder 60 provided in an indoor unit 100 of an air conditioner according to embodiment 2 of the present invention. Fig. 10 is an exploded perspective view of a sensor holder 60 provided in an indoor unit 100 of an air conditioner according to embodiment 2 of the present invention, as viewed from another direction. Parts having the same configurations as those of the indoor unit 100 of fig. 1 to 8 are given the same reference numerals, and description thereof is omitted. An indoor unit 100 according to embodiment 2 will be described with reference to fig. 9 and 10. As described above, the refrigerant detection sensor 50 and the temperature sensor 70 are provided in the sensor holder 60. The refrigerant detection sensor 50 and the temperature sensor 70 are separated in a sensor holder 60. Here, the refrigerant detection sensor 50 accelerates the chemical reaction by applying a voltage to the gas sensor, for example, but the temperature of the gas sensor reaches a temperature of 300 to 400 ℃. Therefore, in the indoor unit 100 according to embodiment 2, the partition 63 is provided in the sensor holder 60 between the refrigerant detection sensor 50 and the temperature sensor 70 so as not to affect the temperature detected by the temperature sensor 70 for detecting the temperature of the air taken in from the room. In the sensor holder 60, the space of the first receiving portion 61 and the space of the second receiving portion 62 are partitioned by the partition 63. The partition 63 is formed of two plates, i.e., a plate portion 63a and a plate portion 63b, which separate the space in which the refrigerant detection sensor 50 is disposed and the space in which the temperature sensor 70 is disposed. The plate portion 63a and the plate portion 63b constituting the partition portion 63 are disposed to face each other, and a space is formed between the plates. The partition 63 may be formed of a single plate in which the plate portion 63a and the plate portion 63b are integrated, instead of forming a space between the plate portion 63a and the plate portion 63 b.

As described above, in the indoor unit 100 of the air conditioner, the space of the first housing portion 61 and the space of the second housing portion 62 of the sensor holder 60 are partitioned by the partition portion 63. Therefore, the indoor unit 100 can prevent the temperature detected by the temperature sensor 70 from being affected by the parallel arrangement of the refrigerant detection sensors 50 in the sensor holder 60.

Embodiment 3.

[ air conditioner 200]

Fig. 11 is a schematic diagram showing the structure of an air conditioner 200 according to embodiment 3 of the present invention. The indoor unit 100 used in the air conditioner 200 according to embodiment 3 is the same as the indoor unit 100 according to embodiments 1 and 2 shown in fig. 1 to 10. The air conditioner 200 according to embodiment 3 performs air conditioning by heating or cooling a room by transferring heat between outside air and the air in the room via a refrigerant. The air conditioner 200 according to embodiment 3 includes an outdoor unit 150 and an indoor unit 100. In the air conditioner 200, the outdoor unit 150 and the indoor units 100 are connected by

refrigerant pipes

300 and 400 to form a refrigerant circuit in which a refrigerant circulates. The refrigerant pipe 300 is a gas pipe through which a gas-phase refrigerant flows, and the refrigerant pipe 400 is a liquid pipe through which a liquid-phase refrigerant flows. A two-phase gas-liquid refrigerant may flow through the refrigerant pipe 400. In the refrigerant circuit of the air conditioner 200, the compressor 31, the flow switching device 32, the outdoor heat exchanger 33, the expansion valve 34, and the indoor heat exchanger 30 are connected in this order by refrigerant pipes. The refrigerant used in the air conditioner 200 is a refrigerant having a density higher than that of air. However, the refrigerant used in the air conditioner 200 is not limited to a refrigerant having a density greater than that of air, and a refrigerant having a density equal to or less than that of air may be used.

(outdoor machine 150)

The outdoor unit 150 includes a compressor 31, a flow switching device 32, an outdoor heat exchanger 33, and an expansion valve 34. The compressor 31 compresses and discharges the sucked refrigerant. Here, the compressor 31 may be provided with an inverter device, or may be configured to be capable of changing the capacity of the compressor 31 by changing the operating frequency by the inverter device. The capacity of the compressor 31 is an amount of refrigerant sent per unit time. The flow path switching device 32 is, for example, a four-way valve, and is a device for switching the direction of the refrigerant flow path. The air conditioner 200 can perform a heating operation or a cooling operation by switching the flow of the refrigerant using the flow switching device 32 based on an instruction from a control device (not shown).

The outdoor heat exchanger 33 performs heat exchange between the refrigerant and outdoor air. The outdoor heat exchanger 33 functions as an evaporator during the heating operation, and exchanges heat between the low-pressure refrigerant flowing in from the refrigerant pipe 400 and the outdoor air to evaporate and gasify the refrigerant. The outdoor heat exchanger 33 functions as a condenser during the cooling operation, and condenses and liquefies the refrigerant by exchanging heat between the refrigerant compressed by the compressor 31 and the outdoor air flowing from the flow switching device 32 side. The outdoor heat exchanger 33 is provided with an outdoor fan 36 for improving the efficiency of heat exchange between the refrigerant and the outdoor air. The outdoor fan 36 may be equipped with an inverter device, and the rotational speed of the fan may be changed by changing the operating frequency of the fan motor. The expansion valve 34 is an expansion device (flow rate control means) and functions as an expansion valve by adjusting the flow rate of the refrigerant flowing through the expansion valve 34, and the pressure of the refrigerant is adjusted by changing the opening degree. For example, when the expansion valve 34 is an electronic expansion valve or the like, the opening degree is adjusted based on an instruction from a control device (not shown) or the like.

(indoor unit 100)

The indoor unit 100 includes an indoor heat exchanger 30 that exchanges heat between the refrigerant and the indoor air, and an indoor blower 37 that adjusts the flow of air that is exchanged heat by the indoor heat exchanger 30. The indoor heat exchanger 30 functions as a condenser during the heating operation, and exchanges heat between the refrigerant flowing in from the refrigerant pipe 300 and the indoor air to condense and liquefy the refrigerant and flow out to the refrigerant pipe 400 side. The indoor heat exchanger 30 functions as an evaporator during the cooling operation, exchanges heat between the refrigerant in a low-pressure state by the expansion valve 34 and the indoor air, evaporates and gasifies the refrigerant by taking the heat of the air away, and flows out to the refrigerant pipe 300 side. The indoor blower 37 is provided to face the indoor heat exchanger 30. The operating speed of the indoor fan 37 is determined according to the setting of the user. An inverter device may be attached to the indoor fan 37 to change the rotational speed of the fan by changing the operating frequency of the fan motor.

[ operation example of air conditioner 200]

Next, the cooling operation will be described as an example of the operation of the air conditioner 200. The high-temperature and high-pressure gas refrigerant compressed and discharged by the compressor 31 flows into the outdoor heat exchanger 33 through the flow switching device 32. The gas refrigerant flowing into the outdoor heat exchanger 33 is condensed by heat exchange with the outside air blown by the outdoor fan 36, becomes a low-temperature refrigerant, and flows out of the outdoor heat exchanger 33. The refrigerant flowing out of the outdoor heat exchanger 33 is expanded and decompressed by the expansion valve 34, and becomes a low-temperature low-pressure two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the indoor heat exchanger 30 of the indoor unit 100, is evaporated by heat exchange with the indoor air blown by the indoor blower 37, turns into a low-temperature and low-pressure gas refrigerant, and flows out of the indoor heat exchanger 30. At this time, the indoor air cooled by the heat absorbed by the refrigerant becomes air-conditioned air (blown air), and is blown out into the room (air-conditioned space) from the air outlet 13c of the indoor unit 100. The gas refrigerant flowing out of the indoor heat exchanger 30 is sucked into the compressor 31 via the flow switching device 32 and is compressed again. The above operations are repeated.

Next, a heating operation will be described as an example of the operation of the air conditioner 200. The high-temperature and high-pressure gas refrigerant compressed and discharged by the compressor 31 flows into the indoor heat exchanger 30 of the indoor unit 100 via the flow switching device 32. The gas refrigerant flowing into the indoor heat exchanger 30 is condensed by heat exchange with the indoor air blown by the indoor air blower 37, becomes a low-temperature refrigerant, and flows out of the indoor heat exchanger 30. At this time, the indoor air heated by the heat of the gas refrigerant becomes air-conditioned air (blown air), and is blown out into the room (air-conditioned space) from the air outlet 13c of the indoor unit 100. The refrigerant flowing out of the indoor heat exchanger 30 is expanded and decompressed by the expansion valve 34, and becomes a low-temperature low-pressure gas-liquid two-phase refrigerant. The two-phase gas-liquid refrigerant flows into the outdoor heat exchanger 33 of the outdoor unit 150, is evaporated by heat exchange with the outside air blown by the outdoor blower 36, turns into a low-temperature low-pressure gas refrigerant, and flows out of the outdoor heat exchanger 33. The gas refrigerant flowing out of the outdoor heat exchanger 33 is sucked into the compressor 31 via the flow switching device 32 and is compressed again. The above operations are repeated.

As described above, by providing the indoor unit 100 according to embodiment 1 or 2 with the air conditioner 200, the air conditioner 200 having the effect according to embodiment 1 or 2 can be obtained. Since the air conditioner 200 according to embodiment 3 includes the indoor unit 100 according to embodiment 1 or 2, it is possible to realize a safe air conditioner 200 in which the refrigerant detection sensor 50 detects leakage of the refrigerant without reaching the lower limit ignition density.

The embodiments of the present invention are not limited to the above embodiments 1 to 3, and various modifications can be added. For example, in embodiment 1 described above, the through-holes 61d and the through-holes 62d are formed in slit shapes, but a plurality of circular through-holes having an opening diameter smaller than the thickness of a human finger may be provided. In addition, although the indoor unit 100 of the four-sided cassette type in which the air outlets 13c are formed in four directions has been described, the air outlets 13c may be formed in one direction or in more than one direction such as two directions. Further, the indoor unit 100 of the ceiling-embedded type has been described, but the indoor unit 100 is not limited to the ceiling-embedded type and may be of a wall-mounted type, for example.

Description of the reference numerals

10 … a housing; 11 … a top plate; 12 … side panels; 13 … decorative panels; 13a … opening; 13b … outer edge portion; 13c … outlet port; 14 … suction grill; 14a … suction inlet; 15 … leaf blades; 16 … socket; 20 … blower; 30 … indoor heat exchanger; 31 … compressor; 32 … flow path switching device; 33 … outdoor heat exchanger; 34 … expansion valve; 36 … outdoor blower; 37 … indoor blower; 40 … electrical component box; 40a … side walls; 50 … refrigerant detection sensor; 51 … detection part; 60 … sensor holder; 61 … a first receiving part; 61a … bottom; 61b … top plate; 61c … side walls; 61d … through holes; 61e … side wall; 61f … wall; 62 … a second receiving portion; 62a … bottom; 62b … top plate; 62c … side walls; 62d … through holes; 62e … side walls; 62f … wall; 62g … center; a 63 … divider; 63a … plate portion; 63b … plate portion; 64b … bulge; 64b1 … front end; 64b2 … opening; 64b3 … through holes; a 70 … temperature sensor; 80 … a control unit; 100 … indoor unit; 150 … outdoor unit; 200 … air conditioner; 300 … refrigerant piping; 400 … refrigerant piping.

Claims

1. An indoor unit of an air conditioner, comprising:

a suction grill having a suction port through which gas flows;

a decorative panel to which the suction grille is attached and in which a blow-out port through which the gas flows out is formed;

a casing to which the decorative panel is attached and which forms an air passage between the suction port and the discharge port;

a blower that is disposed in the casing so as to face the suction grille, and that causes the gas to flow in from the suction port and causes the gas to flow out from the discharge port;

a heat exchanger disposed in the casing in the air passage between the blower and the outlet port, the heat exchanger exchanging heat between the refrigerant flowing inside and the gas; and

a refrigerant detection sensor that detects leakage of the refrigerant,

the suction grill is disposed below the heat exchanger,

the refrigerant detection sensor is disposed below the heat exchanger and between the suction grill and the blower.

2. An indoor unit of an air conditioner according to claim 1,

the detection portion of the refrigerant detection sensor is provided at a right angle to the flow of the gas from the suction port toward the blower.

3. The indoor unit of an air conditioner according to claim 1 or 2,

further comprises a box-shaped sensor holder for fixing the refrigerant detection sensor in the housing,

the refrigerant detection sensor is disposed in the sensor holder.

4. An indoor unit of an air conditioner according to claim 3,

the sensor holder is disposed between the suction grill and the blower.

5. The indoor unit of an air conditioner according to claim 3 or 4, wherein,

and an electric component box having a control device for controlling an indoor unit of the air conditioner therein,

the sensor holder is fixed to a side wall of the electrical component box.

6. An indoor unit of an air conditioner according to any one of claims 3 to 5, wherein,

a plurality of through holes are formed in the sensor holder at positions facing the refrigerant detection sensor,

the width between the walls of the sensor holder forming the through holes is smaller than the thickness of a human finger.

7. An indoor unit of an air conditioner according to any one of claims 3 to 6, wherein,

further comprises a temperature sensor for detecting the temperature of the gas flowing in from the suction port,

the temperature sensor is disposed within the sensor holder.

8. An indoor unit of an air conditioner according to claim 7,

the sensor holder has:

a first housing section that houses the refrigerant detection sensor; and

a second housing portion that houses the temperature sensor,

the space of the first accommodating part and the space of the second accommodating part are separated by a partition part.

9. An indoor unit of an air conditioner according to any one of claims 1 to 8, wherein,

the housing is disposed within a ceiling.

10. An air conditioner is characterized in that,

an indoor unit of an air conditioner according to any one of claims 1 to 9.