JP2015200425A - Outdoor unit of air-conditioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outdoor unit of an air-conditioning device capable of preventing flame generated in a machine space from spreading out thereof without causing the outdoor unit to grow in size.SOLUTION: An outdoor unit of an air-conditioning device has a plurality of ventilation channels in a gap between a cover opening section and a terminal block opening section in a cover space sandwiched by a cover which is detachably installed on a side face of a housing and the side face of the housing. These ventilation channels are formed by the side face of the housing, the cover and a plurality of ribs extended from the cover toward the side face of the housing in a distance between the cover opening section and the terminal block opening section. An effective diameter d of the ventilation channels orthogonal to an air flow direction in the ventilation channels is not less than a flame quenching diameter. A length L of the ventilation channels parallel to the air flow direction is set in a manner that prevents the flame generated in a machine space from spreading through the ventilation channels.

Description

  The present invention relates to an outdoor unit of an air conditioner using a refrigerant having either flammability or slightly flammability.

  As a fire countermeasure when a flammable refrigerant such as R32 is used, it is important to prevent the flame from spreading outside even if a fire occurs in the outdoor unit. One possible method is to seal the machine room so that the flame does not propagate outside.

  However, in order to cool the board accommodated in the electrical unit, it is necessary to introduce air from the outside and release the heat of the board to the outside. Therefore, the outdoor unit of the air conditioner is provided with an outside air introduction port. It is common. Therefore, it is difficult to employ a structure that seals the machine room.

  Therefore, in the outdoor unit using R32 refrigerant, flame propagation is prevented by setting the effective diameter of the opening of the outside air inlet to 3.5 mm or less.

The effective diameter is expressed as follows:
Effective diameter = 4 × opening area [mm ^ 2] / perimeter of opening [mm]

  In the case of R32 refrigerant, it is described in Non-Patent Document 1 and the like that a flame does not pass through a hole having an effective diameter of about 3 mm or less.

Slightly Refrigerant Refrigerant Risk Assessment Study Group, Progress Report 2012, March 2013, Japan Society of Refrigerating and Air Conditioning, 3-4 Progress of AIST Environmental Chemistry Research Division, 42 pages.

  By the way, the casing is provided with a terminal block opening for exposing the terminal block, and air for cooling the substrate is introduced from the terminal block opening when the nonflammable refrigerant is used. However, when a flammable refrigerant is used, the opening must be made smaller than the extinguishing diameter so that it does not propagate outside even if a flame occurs inside. Here, the extinguishing diameter refers to an effective diameter through which a flame cannot pass.

  However, since the size of the terminal block opening is limited because it exposes the mounting portion of the terminal block, it is difficult to make the diameter smaller than the extinguishing diameter.

  The terminal block opening is covered with a cover to prevent rainwater and the like from entering the housing, and the cover is further down from the terminal block opening to introduce air from the outside into the terminal block opening. A cover opening that opens to the outside is provided at a distant position. Therefore, by forming a flow path in the interior space of the cover and making the effective diameter of the flow path cross section at a part of the flow path equal to or less than the extinguishing diameter, even if the flame passes through the terminal block opening, Can be prevented. For example, by providing a partition plate that partitions the terminal block opening and the cover opening in the flow path, and providing a hole with an effective diameter equal to or less than the extinguishing diameter in the partition plate, even if a flame occurs in the housing, the hole is Does not pass through and can prevent flame propagation.

  However, when the effective diameter of the cross section of the flow path is made equal to or less than the extinguishing diameter, the opening area is reduced and the amount of air introduced is reduced. In addition, if a plurality of openings having a diameter equal to or smaller than the flame extinguishing diameter are provided in order to increase the opening area, a space for providing the openings becomes large, leading to an increase in the size of the outdoor unit.

  In view of the circumstances as described above, an object of the present invention is to provide an outdoor unit of an air conditioner that can prevent a flame generated in a machine room from propagating to the outside without causing an increase in size. .

  In order to achieve the above object, an outdoor unit of an air conditioner according to an embodiment of the present invention is an outdoor unit of an air conditioner using a flammable refrigerant, and the outdoor unit and the indoor unit are electrically connected. A terminal block that relays the wiring for connecting to the terminal unit, a terminal block opening that opens into the machine room of the outdoor unit, and an operation valve that connects the refrigerant pipe on the outdoor unit side to the indoor unit side An operation valve mounting portion; a housing side surface in which the terminal block opening is disposed in the upper portion and the operation valve mounting portion is disposed in the lower portion; and the terminal block opening portion and the A cover that covers the operation valve mounting portion from the outside, a cover space formed by the side surface of the housing and the cover, and a cover space and the terminal block opening provided at positions facing the operation valve mounting portion of the cover To the machine room via An effective diameter of a flow path cross section perpendicular to an air flow direction between the cover opening and the terminal block opening in the cover space, and a cover space cross-sectional effective diameter D; One or more ribs that are parallel to the air flow direction from the opening side to the terminal block opening side, extend from the cover toward the side surface of the housing, and have end surfaces that contact the side surface of the housing. A plurality of ventilation paths formed by dividing the cross-section of the flow path into a plurality of sections by the ribs, and the ventilation path has an effective diameter of the ventilation path effective diameter d (d <D The effective diameter d of the ventilation path is larger than the extinguishing diameter, and the length L of the ventilation path parallel to the air flow direction is such that the flame generated in the machine chamber does not pass through the ventilation path. It is characterized by defining It is intended.

  Moreover, the outdoor unit of the air conditioner according to one aspect of the present invention is characterized in that the effective diameter d of the ventilation path can be determined to be larger as the length L of the ventilation path becomes longer.

  ADVANTAGE OF THE INVENTION According to this invention, propagation to the exterior of the flame which generate | occur | produced in the outdoor unit of an air conditioner can be prevented, without causing enlargement.

It is a perspective view which shows the external appearance of the outdoor unit of the air conditioner which is one Embodiment of this invention from a front side right diagonal direction. It is a perspective view which shows the external appearance of the outdoor unit of FIG. 1 from the back side diagonal direction. It is a perspective view which shows the internal structure of the outdoor unit of FIG. 1 from the front side right diagonal direction. It is a perspective view which shows the state which removed the electrical equipment cover from the right side panel of the outdoor unit of FIG. It is the side view which looked at the electrical equipment cover of FIG. 1 from the back side. It is sectional drawing of FIG. It is a perspective view which shows the back side of the electrical equipment cover of FIG. It is a top view explaining the ventilation path of the electrical equipment cover of FIG. It is a figure which shows a test result. It is sectional drawing of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an external appearance of an outdoor unit of an air conditioner according to an embodiment of the present invention as viewed from the front right diagonal direction.
FIG. 2 is a perspective view showing the appearance of the outdoor unit of FIG.
FIG. 3 is a perspective view showing the internal structure of the outdoor unit shown in FIG.

  As shown in these drawings, the outdoor unit 1 of the air conditioner of the present embodiment has a box-shaped housing 10. The housing 10 includes a base 11 that forms the lower surface of the housing 10, a front panel 13 that forms the front surface of the housing 10, a left panel 14 and a right panel 15 that form the side surfaces of the housing 10, and the housing 10. And the top plate 16 that forms the upper surface of the. The front panel 13 is provided with an air outlet 131. A fan guard 17 is attached to the outside of the air outlet 131. The configuration of the right panel 15 will be described later.

  The casing 10 houses a compressor 21, a refrigerant pipe 22, a heat exchanger 23, a blower fan 24, an electrical unit 25, and the like.

  The internal space of the housing 10 is a heat exchange in which a machine room 31 in which a compressor 21, a refrigerant pipe 22 and an electrical unit 25 are mainly arranged by a partition plate 26, a blower fan 24, and a heat exchanger 23 are arranged. It is partitioned from the chamber 32.

  The heat exchanger 23 is provided in an L shape along the left side surface from the back surface of the housing 10. As the refrigerant flowing through the heat exchanger 23, for example, a combustible refrigerant such as R32 is used.

  The electrical unit 25 accommodates a board on which electronic components constituting a control circuit and a power supply circuit for controlling the compressor 21 and the blower fan 24 are mounted. Further, a terminal block holder 252 that holds the terminal block 251 is attached to the electrical unit 25. Further, the electrical unit 25 has an opening (not shown) on the heat exchange chamber 32 side, and when the blower fan 24 is driven, the terminal block opening 151 (to be described later) of the right panel 15 enters the machine chamber 31. Outside air is introduced (arrow A in FIG. 4), and the introduced air flows into the electrical unit 25 and is introduced into the heat exchange chamber 32 through an opening (not shown) of the electrical unit 25. The substrate in the electrical unit 25 is cooled by this air flow.

(Configuration of right panel 15)
As shown in FIGS. 1 and 2, an electrical cover 41 as a cover is detachably attached to the right panel 15.

FIG. 4 is a perspective view illustrating a state in which the electrical cover 41 is removed from the right panel 15.
The portion of the right panel 15 covered by the electrical cover 41 has a terminal block opening 151 that exposes the mounting portion of the terminal block 251 in the terminal block holder 252 and an operation valve mounting portion 153 that exposes the operation valve 27 connecting the pipes. Is provided. The electrical cover 41 is for preventing water and the like from entering the machine room 31 from the outside through these openings 151 and 153, and is formed smaller than the casing 10 of the outdoor unit 1. The terminal block 251 is for relaying the wiring for connecting the outdoor unit 1 and the indoor unit (not shown).

  FIG. 5 is a side view of the right panel 15 to which the electrical cover 41 is attached as viewed from the back side, FIG. 6 is a cross-sectional view of FIG. 5, and FIG.

  As shown in FIG. 7, the back side of the electrical cover 41 is formed in a dome shape. Therefore, as shown in FIG. 6, the electrical cover 41 forms a cover space 41 </ b> A that allows outside air to flow between the front surface 15 e (side surface of the casing) of the right panel 15.

  The electrical cover 41 includes a portion 411 corresponding to the terminal block opening 151, a portion 413 corresponding to the operation valve mounting portion 153, and a portion 415 that connects these two portions 411 and 413.

  A portion 413 corresponding to the operation valve attachment portion 153 is configured to cover the operation valve 27 protruding outside the right panel 15 through the operation valve attachment portion 153. Further, a cover opening 414 is provided on the back surface of the portion 413 corresponding to the operation valve mounting portion 153 for connecting piping from an indoor unit (not shown). This cover opening 414 also plays a role of introducing outside air (arrow B in FIG. 2) into the cover space 41A of the electrical equipment cover 41 from the outside.

  A portion 411 corresponding to the terminal block opening 151 is a portion for covering the terminal block holder 252 exposed from the terminal block opening 151 and guiding outside air to the machine chamber 31 through the operation valve mounting portion 153.

  A portion 415 that connects a portion 411 corresponding to the terminal block opening 151 and a portion 413 corresponding to the operation valve mounting portion 153 has a plurality of ventilation paths 51 between the surface 15e (side surface of the housing) of the right panel 15. A space for providing is formed.

(Configuration of a plurality of ventilation paths 51)
Next, the structure of the several ventilation path 51 is demonstrated using FIG.6, FIG.7, FIG.8.
In the cover space 41 </ b> A, the plurality of ventilation paths 51 are provided between the cover opening 414 and the terminal block opening 151.

  When the blower fan 24 is driven, outside air (arrow C) introduced from the outside into the cover space 41A through the cover opening 414 flows to the terminal block opening 151 through the plurality of ventilation paths 51, and this terminal It is introduced into the machine room 31 through the table opening 151. The air introduced into the machine chamber 31 takes heat of the substrate while passing through the electrical unit 25, moves to the heat exchange chamber 32, and is discharged to the outside from the blower outlet 131.

  By the way, as long as there is a restriction that the size and shape of the terminal block opening 151 is determined so as to expose the mounting portion of the terminal block 251 in the terminal block holder 252, the terminal block opening 151 is configured to satisfy the condition of the flame extinguishing diameter. It is difficult in practice. Therefore, a method of preventing flame propagation by setting the effective diameter of the cross section of the plurality of ventilation paths 51 to be equal to or less than the extinguishing diameter is conceivable. However, with this method, it is not possible to obtain a cross-sectional area of the channel for obtaining the amount of outside air introduced for cooling the substrate.

  Therefore, in the present embodiment, the effective diameter D of the plurality of ventilation paths 51 is set to a size that allows the necessary outside air introduction amount to be obtained, and the length L is set to a length that does not allow the flame to pass therethrough. Thus, the outside air for cooling the substrate is sufficiently introduced, and the propagation of the flame to the outside is prevented.

  The plurality of ventilation paths 51 are formed from the front surface 15e (see FIG. 6) of the right panel 15, the rear surface 41e (see FIG. 6) of the electrical cover 41, and the electrical cover 41 from the cover opening 414 side to the terminal block opening 151 side. One or more ribs 53 (see FIGS. 7 and 8) extending toward the surface 15e of the right panel 15 are formed.

  The one or more ribs 53 include two side surfaces 53a and 53b (see FIG. 8) along the outside air ventilation path 51, a surface 53c (see FIG. 8) on the outside air introduction side, and a surface on the outside air deriving side. 53d (see FIG. 8) and a panel contact surface 53e (see FIG. 7) that is in close contact with the surface 15e of the right panel 15. In a state where the electrical cover 41 is attached to the right panel 15, the panel contact surface 53 e of each rib 53 is in close contact with the surface 15 e of the right panel 15. As a result, the four sides are surrounded by the side surfaces 53a and 53b of the ribs 53, the back surface 41e of the electrical cover 41 (see FIG. 6), and the front surface 15a of the right panel 15 (see FIG. 6). A plurality of ventilation paths 51 each having an opening on the outlet side are formed.

  FIG. 10 shows a cross section (aa ′) perpendicular to the direction of circulation (arrow C) of the outside air at the position where the rib 53 is attached in the cover space 41A of FIG. The effective diameter of the cover space 41A (indicated by the dotted line in the figure) formed by the front surface 15e of the right panel 15 and the back surface 41e of the electrical cover 41 is D, and the ventilation path 51 formed by being divided by the respective ribs 53 etc. When the effective diameter is d, the relationship d <D naturally holds.

  In addition, wiring for electrically connecting to an indoor unit (not shown) is attached to the terminal block 251. The wiring with one end attached to the terminal block 251 is usually drawn out from the cover opening 414 through the cover space 41A, and the other end is attached to the indoor unit. Therefore, it is necessary to provide a wiring path (not shown) other than the ventilation path 51.

  A plurality of ventilation paths 51 are provided in order to obtain a necessary flow rate of outside air. At this time, since the length L of the ventilation path 51 is such that the flame does not pass through, the cross-sectional shape and area of each ventilation path 51 can be selected with a high degree of freedom without being restricted by the extinguishing diameter. it can. Therefore, it can be set as the ventilation path 51 whose effective diameter d is more than a flame extinguishing diameter. As shown in FIGS. 5 and 6, the electrical cover 41 protects the operation valve 27 protruding from the surface 15 e of the right panel 15, so that the cover space 41 </ b> A has the operation valve mounting portion 153 rather than the terminal block opening 151 side. It is formed to enlarge the side. For this reason, the effective diameter D of the cross section of the cover space 41A and the effective diameter d of the cross section of the ventilation path 51 increase from the terminal block opening 151 side toward the operation valve mounting portion 153 side. In this case, by setting the terminal block opening 151 side having the smallest effective diameter so as to obtain a necessary flow rate of the outside air, it is possible to secure the amount of outside air necessary for cooling the substrate.

  Originally, the portion 411 corresponding to the terminal block opening 151 and the portion 413 corresponding to the operation valve mounting portion 153 are arranged apart from each other on the top and bottom of the housing 10, so that the length L of the ventilation path 51 is sufficiently high. Can be selected. Therefore, it is possible to make the length L of the ventilation path 51 a length that does not allow the flame to pass.

  The present inventors have tested the relationship between the length L (mm) of the ventilation path 51 through which no flame propagates and the effective diameter d (mm), and derived the following relationship from the results.

The effective diameter d (mm) of the ventilation path 51 may satisfy the following expressions (1) and (2).
When 0 <L <50 (mm)
d <= − 0.0014 × L ^ 2 + 0.15 × L + 3.5 (1)
When 50 <= L <= 200 (mm) d <= 0.02 × L + 6.5 (2)

  FIG. 9 is a graph showing the test results conducted by the present inventors and the above formulas (1) and (2). From the above formulas (1) and (2), the effective diameter D of the ventilation path 51 is shown. May be determined so as to increase as the length L of the ventilation path 51 increases.

  As described above, according to the present embodiment, in the cover space 41A, a plurality of ventilation paths 51 having a length L that does not allow the flame to pass are provided between the cover opening 414 and the terminal block opening 151. Therefore, it is not necessary to provide a dedicated outdoor air inlet on the right panel 15 that satisfies the condition of the extinguishing diameter. For this reason, the structure of the right side panel 15 can be simplified and cost reduction can be achieved. Furthermore, a large area of the right panel 15 is not taken away by the outside air inlet designed so as to satisfy the condition of the extinguishing diameter, and restrictions on installation of parts in the machine room are reduced. Thereby, size reduction of an outdoor unit can be achieved.

  Furthermore, according to the present embodiment, the strength of the electrical cover 41 can be increased by configuring the plurality of ventilation paths 51 with the plurality of ribs 53.

  In this embodiment, although what used R32 as a combustible refrigerant | coolant was demonstrated, this invention is not limited to this, The outdoor unit of the air conditioner whole using a combustible refrigerant | coolant and a slightly flammable refrigerant | coolant Can be applied to.

DESCRIPTION OF SYMBOLS 1 ... Outdoor unit 10 ... Housing 15 ... Right side panel 15a ... Surface of right side panel (side surface of housing)
DESCRIPTION OF SYMBOLS 21 ... Compressor 22 ... Refrigerant piping 23 ... Heat exchanger 25 ... Electrical equipment unit 27 ... Operation valve 31 ... Machine room 41 ... Electrical equipment cover 41A ... Cover space 41e ... Back surface of electrical equipment cover 51 ... Ventilation path 52 ... Opening 53 ... Rib 53a, 53b ... outside air guiding surface 153 ... operation valve mounting portion 251 ... terminal block 252 ... terminal block holder 414 ... cover opening

Claims (2)

An air conditioner outdoor unit using a flammable refrigerant,
A terminal block that relays wiring for electrically connecting the outdoor unit and the indoor unit is attached, and a terminal block opening that opens into the machine room of the outdoor unit;
An operation valve mounting portion to which an operation valve for connecting the outdoor unit and the refrigerant pipe on the indoor unit side is mounted;
The side surface of the housing in which the terminal block opening is disposed in the upper portion and the operation valve mounting portion is disposed in the lower portion,
A cover that is detachably attached to the side surface of the housing, and covers the terminal block opening and the operation valve mounting portion from the outside,
A cover space formed by the casing side surface and the cover;
A cover opening that is provided at a position facing the operation valve mounting portion of the cover and introduces outside air into the machine room through the cover space and the terminal block opening;
The effective diameter of the flow path cross section orthogonal to the air flow direction between the cover opening and the terminal block opening in the cover space is defined as a cover space cross sectional effective diameter D,
One or two or more parallel to the air flow direction from the cover opening side to the terminal block opening side, and extending from the cover toward the housing side surface, the end surface contacting the housing side surface Ribs,
A plurality of ventilation paths formed by dividing the flow path cross-section into a plurality by the ribs, and
The ventilation path is
The effective diameter of the terminal block opening is the ventilation path effective diameter d (d <D),
The ventilation path effective diameter d is larger than the extinguishing diameter, and the length L of the ventilation path parallel to the air flow direction is determined so that the flame generated in the machine room does not pass through the ventilation path. An air conditioner outdoor unit featuring   The outdoor unit for an air conditioner according to claim 1, wherein the effective diameter d of the ventilation path can be determined to be larger as the length L of the ventilation path becomes longer.