EP3263997A1

EP3263997A1 - Air-conditioner outdoor unit

Info

Publication number: EP3263997A1
Application number: EP16755101.9A
Authority: EP
Inventors: Michio Setsu; Yuki Kawano
Original assignee: Sharp Corp
Current assignee: Sharp Corp
Priority date: 2015-02-25
Filing date: 2016-01-25
Publication date: 2018-01-03
Also published as: JP2016156563A; WO2016136351A1; CN110486848B; CN106796038A; CN110486848A; EP3263997A4; JP6475040B2; CN106796038B

Abstract

According to the present invention, an exhaust duct 54 comprises: a first passageway 54a formed at an end in a left-right direction (XI-X2 direction) of an electric component box 50 and extending in a top-bottom direction (Z1-Z2 direction) with an outlet 55 facing the interior of the electric component box 50 provided at an upper end; and a second passageway 54b extending in the left-right direction (X1-X2 direction) with an exhaust opening 53 facing an air blower chamber 14 in which an air blower 40 is disposed, wherein the first passageway 54a and the second passageway 54b are in communication with each other via a communicating opening 56 formed in a peripheral wall lower part of the first passageway 54a, with the exhaust opening 53 disposed above the communicating opening 56 and more spaced apart from the air blower 40 than the outlet 55.

Description

Technical Field

The present invention relates to outdoor units of air conditioners.

Background Art

A conventional outdoor unit of an air conditioner is disclosed in Patent Document 1. This outdoor unit has a heat exchanger and a blower arranged in a housing, and as the blower is driven, outside air having exchanged heat with the heat exchanger is discharged out through an air outlet formed in a front surface of the housing. Inside the housing, an electrical box is arranged which houses in it a circuit board electrically connected to the blower. Air inside the electrical box is discharged toward the blower under suction as the blower is driven, and thereby heat-emitting components mounted on the circuit board are cooled.
The heat exchanger is arranged upright inside the housing and has a holding plate which integrally holds a refrigerant tube, at an end part thereof, which meanders so as to lie side by side in the up/down direction. Here, the heat exchanger is fixed inside the housing by screwing the holding plate onto the circumferential surface of the electrical box.

List of Citations

Patent Literature

Patent Document 1: JP-A-2011-94926

Summary of the Invention

Technical Problem

With the above-described conventional outdoor unit, when a strong wind pressure is applied to the air outlet in the housing, rain drops may enter the housing through the air outlet. Here, rain drops carried on a flow of air enter the electrical box; this may inconveniently cause failure of an electrical system on the circuit board.
The heat exchanger is, with the refrigerant tube bent, housed inside the housing, and thus the refrigerant tube easily deforms during assembly; this makes it difficult to align screw holes in the electrical box with those in the heat exchanger, and inconveniently lowers assembly efficiency.
Devised against the background discussed above, an object of the present invention is to provide an outdoor unit of an air conditioner that can efficiently cool a circuit board which is housed and that can prevent the entry of rain drops into the electrical box.
Devised against the background discussed above, another object of the present invention is to provide an outdoor unit of an air conditioner that offers improved assembly efficiency of a heat exchanger and an electrical box.

Means for Solving the Problem

To achieve the above object, according to one aspect of the present invention, in an outdoor unit of an air conditioner that has, arranged in a housing, a blower and an electrical box housing therein a circuit board connected to the blower, and in which air inside the electrical box being discharged via exhaust ducts under suction by the blower being driven, the exhaust ducts are formed in end parts of the electrical box in the left/right direction respectively, the exhaust ducts each have a first passage which has, in the top end thereof, an outlet hole open into the electrical box and which extends in the up/down direction and a second passage which has discharge holes open to a blower chamber where the blower is arranged and which extends in the left/right direction, the first passage and the second passage communicate with each other via a communication hole in a lower part of the circumferential wall of the first passage, and the discharge holes are formed, above the communication hole, farther away from the blower than the outlet hole is.
In the outdoor unit structured as described above, the exhaust ducts are arranged in front and rear end parts of the electrical box respectively, and the discharge holes are formed outward of the front and rear ends of the blades of the blower with respect to the axial direction of a rotary shaft of the blades.
In the outdoor unit structured as described above, the discharge holes are each provided with a shielding portion which shields a blower side thereof.
To achieve the above object, according to another aspect of the present invention, in an outdoor unit of an air conditioner that has, arranged in a housing, a heat exchanger, a blower, and an electrical box housing therein a circuit board connected to a compressor and the blower, the heat exchanger is arranged upright inside the housing and has a holding plate which integrally holds a refrigerant tube, at an end part thereof, which meanders so as to lie side by side in the up/down direction, the holding plate has a flat portion which fixes the refrigerant tube and a bent portion which is bent into an L-shape from one side end of the flat portion, the electrical box is arranged in an upper part of the housing, and is provided with a protruding portion protruding from a circumferential wall thereof, and the protruding portion has a groove which extends in the up/down direction and in which the flat portion is fitted and an engaging portion which engages with the bent portion.
In the outdoor unit structured as described above, a bottom end of at least one side wall of the groove is formed as an inclined surface.

Advantageous Effects of the Invention

In an outdoor unit of an air conditioner according to the present invention, discharge holes are formed farther away from a blower than an outlet hole and a communication hole are, and thus it is possible to prevent a flow of air containing rain drops splashed from the blower from passing through a second passage from the discharge holes toward the communication hole. The communication hole is formed in a lower part of a first passage extending in the up/down direction, and thus the flow of air containing rain drops can be prevented, by gravity, from passing through the first passage upward. With the first and second passages arranged orthogonal to each other and the discharge holes formed above the communication hole, the air flow passage is bent a plurality of times; this produces a great pressure loss and thus further reduces the entry of rain drops. Thus, it is possible to prevent failure of an electrical system on a circuit board caused by the entry of rain drops into the electrical box via the outlet hole.
In an outdoor unit of an air conditioner according to the present invention, a heat exchanger is fixed to an electrical box as a result of a flat portion which fixes a refrigerant tube at an end part thereof being fitted in a groove which is formed in the circumferential wall of the electrical box and which extends in the up/down direction. Here, by engaging a bent portion bent into an L-shape from one side end of the flat portion with an engaging portion of the electrical box, the heat exchanger is reliably fixed to the electrical box. Thus, it is possible to improve assembly efficiency.

Brief Description of Drawings

[Fig. 1] is an exploded perspective view of an outdoor unit according to a first embodiment of the present invention;
[Fig. 2] is an enlarged perspective view of one end part of a heat exchanger according to the first embodiment of the present invention;
[Fig. 3] is a perspective view of an electrical box according to the first embodiment of the present invention;
[Fig. 4] is a perspective view of an electrical box according to the first embodiment of the present invention;
[Fig. 5] is a perspective view illustrating the movement of a flow of air inside an exhaust duct according to the first embodiment of the present invention;
[Fig. 6] is a top sectional view illustrating the movement of a flow of air inside an exhaust duct according to the first embodiment of the present invention;
[Fig. 7] is a side view of an electrical box according to a second embodiment of the present invention;
[Fig. 8] is a top view of an electrical box according to the second embodiment of the present invention; and
[Fig. 9] is a side view of an electrical box according to a third embodiment of the present invention.

Description of Embodiments

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is an exploded perspective view of an outdoor unit 10. The right hand side and the left hand side as seen from a user standing to face an air outlet 12 in the outdoor unit 10 are referred to as the X1 direction and the X2 direction respectively. The frontward direction and the rearward direction relative to the outdoor unit 10 are referred to as the Y1 direction and the Y2 direction respectively. The upward direction and the downward direction relative to the outdoor unit 10 are referred to as the Z1 direction and the Z2 direction respectively.
The outdoor unit 10 has a box-shaped housing 11, and the housing 11 has a top surface plate 11U arranged at the top and a bottom surface plate 11D arranged at the bottom. As a circumferential surface of the housing 11, there are arranged a front surface plate 11F at the front and a rear surface plate (unillustrated) at the rear. There are further arranged a left side surface plate 11L at the left and a right side surface plate 11R at the right. The left side surface plate 11L and the right side surface plate 11R are each formed in an L-shape as seen from above with a part thereof bent toward the rear surface.
In a central part of the front surface plate 11F of the housing 11, the air outlet 12 is open, which is fitted with a grille 12a. In the rear surface plate, a rear surface air inlet (unillustrated) is open, and in the left side surface plate 11L, a left side surface air inlet 11LS is open. In the right side surface plate 11R, in a rear surface-side part thereof, a right side surface air inlet 11RS is open. The left side surface air inlet 11LS and the right side surface air inlet 11RS are each formed in the shape of a lattice.
Inside of the housing 11, a heat exchanger 24 is arranged upright along the rear surface. The heat exchanger 24 has opposite ends thereof bent to form a substantially U-shape as seen from above. The heat exchanger 24 is arranged to face the left side surface air inlet 11LS, the rear surface air inlet (unillustrated), and the right side surface air inlet 11RS.
The interior of the housing 11 is divided into a blower chamber 14 and a compressor chamber 15 by a partition wall 13 arranged upright from the bottom surface plate 11D. In the blower chamber 14, a blower 40 is arranged in front of the heat exchanger 24. In the compressor chamber 15, a compressor 41 is arranged.
In an upper part of the housing 11, an electrical box 50 is arranged to bridge between the blower chamber 14 and the compressor chamber 15. In the electrical box 50, a circuit board 60 is housed, and the circuit board 60 is arranged so as to cover an opening in the top of the electrical box 50. The circuit board 50 is electrically connected to the blower 40 and the compressor 41 to control the operation of the outdoor unit 10.
The internal wiring in the outdoor unit 10 that connects the circuit board 50 to the compressor 41 and the like extends out of the electrical box 50 via a passage hole 51 which is arranged in a side wall of the electrical box 50 facing the compressor chamber 15. On the other hand, the external wiring that connects the circuit board 50 to an indoor unit (unillustrated) extends out of the electrical box 50 via a passage hole 57 (see Fig. 4) arranged in a side wall of the electrical box 50, and is led out of the housing 11 through a wiring hole 80 formed in the right side surface plate 11R.
Fig. 2 is an enlarged perspective view of one end part of the heat exchanger 24. In the heat exchanger 24, a refrigerant tube 25, of which straight segments extend in the left/right direction (the X1-X2 direction), is arranged so as to meander, with the straight segments side by side at an interval from each other in the up/down direction (the Z1-Z2 direction). The refrigerant tube 25 is, at opposite ends thereof, bent in the front/rear direction (the Y1-Y2 direction), and is fixed to a holding plate 26.
The holding plate 26 has a flat portion 26a and a bent portion 26b, and holds, on the flat portion 26a, the refrigerant tube 25 of which the straight segments lie side by side in the up/down direction. The bent portion 26b is formed by bending one end of the flat portion 26a into an L-shape. The bent portion 26b helps improve the strength of the holding plate 26. The refrigerant tube 25 has fixed to it a large number of fins 25a extending perpendicularly.
The electrical box 60 is provided with a protruding portion 60e composed of a pair of ribs 60c and 60d protruding from the circumferential wall of the electrical box 60. The protruding portion 60e extends in the upward/downward direction (the Z1-Z2 direction), and has a groove 60a formed between the rib 60c and the rib 60d. Opposite side walls of the groove 60a have a predetermined width in the left/right direction (the X1-X2 direction) so as to make surface contact with the flat portion 26a when fitted to the flat portion 26a as will be described later. One rib 60d is bent into a shape with an L-shaped section to form an engaging portion 60b.
The electrical box 60 is inserted from above during assembly, and the groove 60a has the flat portion 26a of the holding plate 26 fitted in it to position the electrical box 60 relative to the heat exchanger 24. Here, the engaging portion 60b engages with the bent portion 26b of the holding plate 26 so that the holding plate 26 is prevented from coming off. Thus, it is possible to improve assembly efficiency of the outdoor unit 1. Moreover, owing to the heat exchanger 24 being fixed as a result of the groove 60a and the flat portion 26a making surface contact with each other, it is possible to prevent deformation of the heat exchanger 24 after it is fixed.
A bottom end of at least one side wall of the groove 60a is preferably formed as an inclined surface. By sliding the top end of the flat portion 26a along the inclined surface formed at the bottom end of the side wall of the groove 60a, it is possible to easily fit the flat portion 26a in the groove 60a. This helps further improve assembly efficiency of the electrical box 60 and the heat exchanger 24.
The protruding portions 60e are arranged at a plurality of places (three places in this embodiment) on the circumferential wall of the electrical box 50. Thus, it is possible to fit the holding plate 26 in any of different grooves 60a which correspond to a plurality of types of outdoor units 1 including heat exchangers 24 having different shapes, and thus to share the electrical box 50.
As the blower 40 is driven, its suction force causes outside air to flow into the blower chamber 14 via the left side surface air inlet 11LS, the rear surface air inlet (unillustrated), and the right side surface air inlet 11RS. The outside air having flowed into the blower chamber 14 exchanges heat with the heat exchanger 24, circulates through the blower chamber 14, and is discharged out through the air outlet 12.
Figs. 3 and 4 are perspective views of the electrical box 50. In a lower part of the bottom surface of the electrical box 50, a heat sink 52 is arranged so as to face the blower chamber 14, and the heat sink 52 is cooled by the flow of air circulating through the inside of the blower chamber 14. Thus, the inside of the electrical box 50 is cooled via the heat sink 52.
In opposite end parts of the electrical box 50 in the front/rear direction (the Y1-Y2 direction), exhaust ducts 54 are provided at two places respectively. The exhaust duct 54 has discharge holes 53 open to the blower chamber 14 and an outlet hole 55 open into the electrical box 50. The discharge holes 53 are formed in the circumferential wall of the electrical box 50. The inside of the electrical box 50 communicates with the compressor chamber 15 via the passage hole 51, and the blower chamber 14 communicates with the compressor chamber 15 via the exhaust ducts 54. The inside of the electrical box 50 communicates also with the outside of the outdoor unit 10 via the passage hole 57.
The discharge holes 53 are each provided with a shielding portion 53a which shields the blower 40 side thereof. The discharge holes 53 are formed outward of the front and rear ends of the blades of the blower 40 with respect to the axial direction of its rotary shaft (the Y1-Y2 direction).
Figs. 5 and 6 are a perspective view and a top sectional view, respectively, illustrating the exhaust duct 54. The exhaust duct 54 has a first passage 54a extending in the up/down direction (the Z1-Z2 direction) and a second passage 54b extending in the left/right direction (the X1-X2 direction). In the first passage 54a, in the top end thereof, the outlet hole 55 is open, and in a lower part of the circumferential wall thereof, a communication hole 56 is open. Via the communication hole 56, the first and second passages 54a and 54b communicate with each other. The second passage 54b has the discharge holes 53, and the discharge holes 53 are formed, above the communication hole 56, farther away from the blower 40 than the outlet hole 55 is.
The air having flowed into the electrical box 50 through the passage holes 51 and 57 under suction by the blower 40 being driven flows into the exhaust ducts 54 via the outlet holes 55. In the front exhaust duct 54, the flow of air having flowed in through the outlet hole 55 passes through the first passage 54a down in the Z2 direction (arrow A1), turns into the frontward direction (the Y1 direction), and flows into the second passage 54b via the communication hole 56 (arrow A2). Then, while moving up in the Z1 direction toward the discharge holes 53, the flow of air turns into the rightward direction (the X1 direction) (arrow A3), and is discharged into the blower chamber 14 via the discharge holes 53. Likewise, the flow of air having flowed into the rear exhaust duct 54 is discharged into the blower chamber 14. In this way, the flow of air circulates through the inside of the electrical box 50; this helps achieve more effective cooling of the circuit board 60.
On the other hand, when the blower 40 is rotated in the reverse direction as a result of a strong wind pressure being applied to the air outlet 12 in rainy weather, with no suction force acting, rain drops splash from the blower 40 on the electrical box 50. Here, the entry of rain drops through the discharge holes 53 is reduced by the shielding portions 53a which shield the blower 40 sides thereof. The discharge holes 53 are formed outward of the front and rear ends of the blades of the blower 40 with respect to the axial direction of its rotary shaft; this further reduces the entry of rain drops through the discharge holes 53.
The discharge holes 53 are formed farther away from the blower 40 than the outlet hole 55 and the communication hole 56 are. Thus, the flow of air containing rain drops splashed from the blower 40 can be prevented from passing through the second passage 54b from the discharge holes 53 toward the communication hole 56. The communication hole 56 is formed in a lower part of the first passage 54a extending in the up/down direction; this permits the flow of air containing rain drops to be prevented, by gravity, from passing through the first passage 54a upward. With the first and second passages 54a and 54b arranged orthogonal to each other and the discharge holes 53 formed above the communication hole 56, the air flow passage is bent a plurality of times; this produces a great pressure loss and thus further reduces the entry of rain drops. Thus, it is possible to prevent the entry of rain drops into the electrical box 50 via the outlet hole 55.
In this embodiment, in the exhaust duct 54, the first passage 54a having the outlet hole 55 in the top end thereof communicates with the second passage 54b via the communication hole 56 formed in a lower part, and the discharge holes 53 are formed, above the communication hole 56, farther away from the blower 40 than the outlet hole 55 is. Thus, it is possible to prevent the flow of air containing rain drops splashed from the blower 40 from passing through the first and second passages 54a and 54b, and to prevent the entry of rain drops into the electrical box 50 via the outlet hole 55.
Owing to the discharge holes 53 being formed outward of the front and rear ends of the blades of the blower 40 with respect to the axial direction of its rotary shaft, it is possible to reduce the entry, through the discharge holes 53, of rain drops splashed from the blower 40. Thus, it is possible to further prevent the entry of rain drops into the electrical box 50.
Owing to the discharge holes 53 each being provided with the shielding portion 53a which shields the blower 40 side thereof, it is possible to reduce the entry, through the discharge holes 53, of rain drops splashed from the blower 40. Thus, it is possible to further prevent the entry of rain drops into the electrical box 50.
The heat exchanger 24 is positioned as a result of one end of the flat portion 26a, which holds the refrigerant tube 25 of which the straight segments lie side by side in the up/down direction, being fixed in the groove 60a, which extends in the up/down direction and which is formed between the pair of ribs 60c and 60d protruding from the circumferential wall of the electrical box 60. The bent portion 26b is formed by bending one end of the flat portion 26a, which is fitted in the groove 60, into an L-shape, and the engaging portion 60b engages with the bent portion 26a of the holding plate 26 so that the holding plate 26 is prevented from coming off. Thus, it is possible to improve assembly efficiency of the outdoor unit 1. Moreover, owing to the heat exchanger 24 being fixed as a result of the groove 60a and the flat portion 26a making surface contact with each other, it is possible to prevent deformation of the heat exchanger 24 after it is fixed.
Owing to a bottom end of at least one side wall of the groove 60a being formed as an inclined surface, it is possible to slide the top end of the flat portion 26a along the inclined surface formed at the bottom end of the side wall of the groove 60a. Thus, it is possible to easily fit the flat portion 26a in the groove 60a, and thereby to improve assembly efficiency of the electrical box 60 and the heat exchanger 24.

Figs. 7 and 8 are a side view and a top view, respectively, of an outdoor unit 10 according to a second embodiment. Such components as find their counterparts in the first embodiment are identified by the same reference sings, and no overlapping description will be repeated. Unlike in the first embodiment, in the second embodiment, in addition to the exhaust ducts 54, exhaust ducts 84 are provided in opposite end parts of the electrical box 50 in the front/rear direction (the Y1-Y2 direction).
The exhaust duct 84 has discharge holes 83 open to the blower chamber 14 and an outlet hole 85 open into the electrical box 50. The outlet hole 85 is formed in a left end part of the electrical box 50, and the discharge holes 83 are formed closer to the blower 40 than the discharge holes 53 are. Via the exhaust ducts 84, the blower chamber 14 and the compressor chamber 15 communicate with each other; this permits a flow of air (arrow B1) to circulate through the inside of the electrical box 50 to achieve still more effective cooling of the circuit board 60. Owing to the outlet hole 85 being formed in a left end part of the electrical box 50, it is possible to cool the circuit board 60 up to an end part of it.
Owing to the discharge holes 83 being formed farther away from the blower 40 than the outlet hole 85 is, the flow of air having flowed into the discharge holes 83 from the blower 40 slows down in the exhaust duct 84; this reduces rain drops that reach the outlet hole 85. Thus, it is possible to prevent the entry of rain drops into the electrical box 50.

Fig. 9 is a side view of an electrical box 50 according to a third embodiment. Such components as find their counterparts in the first embodiment are identified by the same reference sings, and no overlapping description will be repeated. Unlike in the first embodiment, in the third embodiment, discharge holes 53 are formed as a plurality of circular holes arrayed in the up/down and left/right directions. The farther the discharge holes 53 are from the blower 40 in the left/right direction (the X1-X2 direction), the larger the number of discharge holes 53 formed in the up/down direction (the Z1-Z2 direction) and hence their opening area. Thus, it is possible, while discharging a sufficient amount of air, to prevent rain drops from entering via the discharge holes 53 owing to the discharge holes 53 having the smaller area the closer they are to the blower 40.

Industrial Applicability

The present invention is applicable to outdoor units of separate type air-conditioners.

List of Reference Signs

10: outdoor unit
11: housing
11D: bottom surface plate
11R: right side surface plate
12: air outlet
12a: grille
13: partition wall
14: outdoor-side heat exchanger
15: compressor chamber
16: outdoor-side blower
20: partition wall
21: heat exchanger chamber
22: machine chamber
24: heat exchanger
40: blower
41: compressor
50: electrical box
51, 57: passage hole
52: heat sink
53: discharge hole
53a: shielding portion
54: exhaust duct
54a: first passage
54b: second passage
55: outlet hole
56: communication hole
60: circuit board
83: discharge hole
84: exhaust duct
85: outlet hole

Claims

An outdoor unit of an air conditioner having, arranged in a housing, a blower and an electrical box housing therein a circuit board connected to the blower, air inside the electrical box being discharged via exhaust ducts under suction by the blower being driven, wherein
the exhaust ducts are formed in end parts of the electrical box in a left/right direction respectively, the exhaust ducts each having a first passage which has, in a top end thereof, an outlet hole open into the electrical box and which extends in an up/down direction and a second passage which has discharge holes open to a blower chamber where the blower is arranged and which extends in the left/right direction,
the first passage and the second passage communicate with each other via a communication hole in a lower part of a circumferential wall of the first passage, and
the discharge holes are formed, above the communication hole, farther away from the blower than the outlet hole is.
The outdoor unit of claim 1, wherein
the exhaust ducts are arranged in front and rear end parts of the electrical box respectively, and the discharge holes are formed outward of front and rear ends of blades of the blower with respect to an axial direction of a rotary shaft of the blades.
The outdoor unit of claim 1 or 2, wherein
the discharge holes are each provided with a shielding portion which shields a blower side thereof.
An outdoor unit of an air conditioner having, arranged in a housing, a heat exchanger, a blower, and an electrical box housing therein a circuit board connected to a compressor and the blower, wherein
the heat exchanger is arranged upright inside the housing and has a holding plate which integrally holds a refrigerant tube, at an end part thereof, which meanders so as to lie side by side in an up/down direction,
the holding plate has a flat portion which fixes the refrigerant tube and a bent portion which is bent into an L-shape from one side end of the flat portion,
the electrical box is arranged in an upper part of the housing, and is provided with a protruding portion protruding from a circumferential wall thereof, and
the protruding portion has a groove which extends in the up/down direction and in which the flat portion is fitted and an engaging portion which engages with the bent portion.
The outdoor unit of claim 4, wherein
a bottom end of at least one side wall of the groove is formed as an inclined surface.