AU747235B2

AU747235B2 - Air conditioner

Info

Publication number: AU747235B2
Application number: AU64739/00A
Authority: AU
Inventors: Mikio Ito; Hiroshi Masuda; Yuuichi Terada
Original assignee: Daikin Industries Ltd
Current assignee: Daikin Industries Ltd
Priority date: 1999-08-31
Filing date: 2000-08-10
Publication date: 2002-05-09
Anticipated expiration: 2020-08-10
Also published as: CN1162653C; EP1134505A1; JP3259719B2; KR100385610B1; HK1042541A1; CN1335922A; AU6473900A; HK1042541B; JP2001065914A; EP1134505A4; WO2001016532A1; KR20010080343A

Description

1 AIR CONDITIONER TECHNICAL FIELD The present invention relates to an air conditioner and, more particularly, to an air conditioner improved in the placement space of an electrical-equipment unit.

BACKGROUND ART Fig. 15 is a perspective front view showing an indoor unit of an air conditioner which is a prior-art example. Within a body casing 81, is provided an indoor heat exchanger 82 made up by connecting a front-side heat exchanger and a rear-side heat exchanger in an inverted-V shape to each other. Then, a cylindrical cross flow fan 83 is set so as to be sandwiched by this inverted V of the indoor heat exchanger 82. This cross flow fan 83 is driven into rotation by a fan motor 85 provided on the right side of the indoor heat exchanger 82. By this fan motor being driven into rotation, indoor air is sucked in from the front of the indoor heat exchanger 82 and heatexchanged by the indoor heat exchanger 82. Thereafter, conditioning air is blown out into the room from below the indoor heat exchanger 82.

2 The indoor heat exchanger 82 has auxiliary piping 86 led out from its right side as viewed in the figure.

This auxiliary piping 86 is made up of a liquid pipe and a gas pipe that form a refrigerator circuit in connection with an outdoor unit (not shown). The auxiliary piping 86, after led out from the indoor heat exchanger 82, is laid out on the right side of the indoor heat exchanger 82.

Further, connecting piping 88 is formed so as to adiabatically cover the auxiliary piping 86, and the connecting piping 88 is laid out from right to left side of the body casing 81 along the rear side of the body casing 81. Furthermore, an electrical-equipment box 90 for providing electrical equipment including a microcomputer, a power amplifier for motor driving use and the like is provided on the right side of the auxiliary piping 86 so as not to obstruct the air flow passage.

In this indoor unit, the auxiliary piping 86 led out from the indoor heat exchanger 82 is laid out on the right side of the indoor heat exchanger 82. Further on the right side of the auxiliary piping 86, is provided the electrical-equipment box 90. That is, the lead-out space of the auxiliary piping 86 and the electrical-equipment box occupy two spaces that do not directly contribute to heat exchange within the body casing 81, making it inevitable to lessen the width of the indoor heat exchanger -3- 82 to an extent corresponding to these two spaces. Of course, from the viewpoint of air-conditioning efficiency, the width of the indoor heat exchanger 82 is desired to be larger. On the other hand, enlarging the width of the body casing 81 is undesirable in view of the limitation on installation space and maintaining a good workability of installation. Thus, it has been desired that spaces which do not directly contribute to heat exchange within the body casing 81 are as small as possible, while the width of the indoor heat exchanger 82 is enlarged without increasing the width of the body casing 81, by which the air-conditioning efficiency is improved.

DISCLOSURE OF THE INVENTION The present invention having been accomplished to solve the foregoing issues of the prior art, an object of the invention is to provide an air conditioner which is capable of improving the air-conditioning efficiency by enlarging the dimensions of the heat exchanger without enlarging the body casing, or which allows the body casing to be made compact without decreasing the dimensions of the heat exchanger.

In order to achieve the above object, there is provided an air conditioner having an electrical-equipment unit placed within an indoor-unit casing, wherein the 4electrical-equipment unit comprises a high-voltage circuit section and a low-voltage circuit section arranged in this order, as viewed from a power input section side, along a lengthwise direction of the indoor-unit casing.

In the air conditioner of this constitution, since the circuit construction of the electrical-equipment unit is given in a series layout along the lengthwise direction of the indoor-unit casing, the electricalequipment unit can be formed into a long, narrow shape along the lengthwise direction of the indoor-unit casing.

Therefore, it becomes possible to place the electricalequipment unit at various spaces as viewed in a cross section perpendicular to the lengthwise direction of the indoor-unit casing. This means that no special space for placing electrical equipment is needed in a side portion of the indoor-unit casing, as would be required in the prior art. Therefore, the indoor unit can be reduced in its lengthwise dimension, so that the indoor unit can be made more compact. This means, from the opposite standpoint, that the placement spaces for the heat exchanger and the fan can be increased in an indoor unit having the same size as conventional ones. Thus, the air-conditioning performance can be improved over the prior art.

In one embodiment of the invention, an AC circuit section, a DC high-voltage circuit section and a DC low- 11 1.

5 voltage circuit section are placed in this order as viewed from an AC power input section side.

In the air conditioner of this embodiment, similarly, the advantages of more compactness of the indoor unit as well as improvement in air-conditioning performance can be obtained. This circuit construction is suitable for cases where voltage conversion is performed after alternating current is converted into direct current.

In one embodiment of the invention, an AC highvoltage circuit section, an AC low-voltage circuit section and a DC low-voltage circuit section are placed in this order as viewed from an AC power input section side.

In the air conditioner of this embodiment, similarly, the advantages of more compactness of the indoor unit as well as improvement in air-conditioning performance can be obtained. This circuit construction is suitable for cases where step-down is performed with a transformer or the like.

In one embodiment of the invention, a DC highvoltage circuit section and a DC low-voltage circuit section are placed in this order as viewed from a DC power input section.

In the air conditioner of this embodiment, similarly, the advantages of more compactness of the indoor unit as well as improvement in air-conditioning performance -6can be obtained. This circuit construction is suitable for models in which an AC/DC conversion section is provided outside the unit.

In one embodiment of the invention, the power input section is provided on one side within the indoorunit casing on which a high-voltage drive actuator is placed.

In the air conditioner of this embodiment, since the high-voltage drive actuator is located closer to the high-voltage circuit section side, the connecting harness is shortened, allowing the construction to be simplified and the connecting and assembling work to be facilitated.

In one embodiment of the invention, a low-voltage drive actuator is provided on one side within the indoorunit casing on which the low-voltage circuit section is placed, the one side being opposite to a side on which the high-voltage drive actuator is provided.

In the air conditioner of this embodiment, since the low-voltage drive actuator is located closer to the low-voltage circuit section side, the connecting harness is further shortened, allowing the construction to be simplified and the connecting and assembling work to be further facilitated.

In one embodiment of the invention, the highvoltage drive actuator is an indoor-fan driving motor and 7the low-voltage drive actuator is a flap-control motor.

This air conditioner is suitable for this embodiment.

In one embodiment of the invention, a singularity or plurality of the circuit sections as a unit block are accommodated on one printed circuit board, and a plurality of the printed circuit boards are arrayed along a lengthwise direction of the indoor-unit casing.

In the air conditioner of this embodiment, since a singularity or plurality of circuit sections as a unit block are accommodated on one printed circuit board, the maintenance work can be facilitated.

In one embodiment of the invention, a lengthwise size of a space where the electrical-equipment unit is placed is 1/2 or more of a lengthwise size of the indoorunit casing.

In the air conditioner of this embodiment, since the electrical-equipment unit is long, narrow shaped along the lengthwise direction of the indoor-unit casing, it becomes possible to place the electrical-equipment unit at various spaces as viewed in a cross section perpendicular to the lengthwise direction of the indoor-unit casing.

Therefore, the indoor unit can be reduced in its lengthwise size, so that the advantages of more compactness of the indoor unit as well as improvement in air-conditioning performance can be obtained, similarly.

-8- In one embodiment of the invention, the electrical-equipment unit is placed at a position above an outlet port of the indoor-unit casing and over a laterally extending region located between a drain pan of an indoor heat exchanger and a front panel of the indoor-unit casing.

When the drain pan is provided on the lower side of the indoor heat exchanger in a region located above the outlet port of the indoor unit as in the air conditioner of this embodiment, the position between this drain pan and the front panel of the indoor-unit casing is a region that inevitably becomes a dead space. Accordingly, placing the electrical-equipment unit in this region allows the space inside the indoor-unit casing to be utilized further effectively. As a result of this, the indoor unit can be made even more compact, and the air-conditioning performance can be further improved.

In one embodiment of the invention, within the electrical-equipment unit, highly self-heating electrical components are placed on an upper side of the printed circuit board.

In the air conditioner of this another embodiment, since the highly self-heating electrical components are placed at positions above the printed circuit board, the heat radiation of the electrical components can be accelerated, and moreover the other -9electrical components can be prevented from being affected by the heat radiation.

In one embodiment of the invention, a heat radiation hole for cooling the electrical-equipment unit is opened toward the front side.

In the air conditioner of this embodiment, by the heat radiation hole being opened toward the front side, air flowing along the front side can accelerate the heat radiation of the highly self-heating electrical components.

Also, since the heat radiation hole is opened toward the front side, the penetration of drain water can be prevented and the reliability of the equipment can be maintained.

In one embodiment of the invention, the power input section is given by a terminal board and an insertion direction of a VVF line in this terminal board is set along the lengthwise direction of the indoor-unit casing.

Also, in one embodiment of the invention, the insertion direction of the VVF line is directed from the power input section toward the DC low-voltage circuit section.

In the air conditioner of this embodiment, the VVF line is inserted into the terminal board along a direction which is the lengthwise direction of the indoorunit casing and which is directed from the AC circuit 0 section to the DC low-voltage circuit section. Inserting the WVF line toward such a direction facilitates the work of inserting and connecting the VVF line itself, and enables the prevention of interference between the VVF line and the individual circuit sections, thus facilitating the line routing work and enabling noise reduction.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic front view showing a first embodiment of the air conditioner according to the invention; Fig. 2 is a schematic front view, similar to the above, showing the first embodiment of the air conditioner of the invention; Fig. 3 is a schematic side view showing the first embodiment of the air conditioner of the invention; Fig. 4 is a sectional view showing the first embodiment of the air conditioner of the invention; Fig. 5 is an exploded perspective view showing the first embodiment of the air conditioner of the invention; Fig. 6 is an exploded perspective view of an example of the electrical-equipment unit to be used for the air conditioner; Fig. 7 is a schematic plan view of the electrical-equipment unit; -11- Fig. 8 is a block diagram showing the circuit construction of the electrical-equipment unit; Fig. 9 is a sectional view showing the structure around the light-emitting display section in the electrical-equipment unit; Fig. 10 is a block diagram showing the circuit construction of the electrical-equipment unit; Figs. 11A and 11B are block diagrams showing modification examples of the circuit construction of the electrical-equipment unit; Fig. 12 is a schematic view showing an arrangement example of the electrical-equipment unit of the air conditioner; Fig. 13 is a schematic view showing an arrangement example in which the electrical-equipment unit is divided; Fig. 14 is a schematic view showing another arrangement example in which the electrical-equipment unit is divided; and Fig. 15 is a schematic view showing an arrangement example of the electrical-equipment unit in a prior art example.

BEST MODE FOR CARRYING OUT THE INVENTION -12- Next, concrete embodiments of the air conditioner according to the present invention are described in detail with reference to the accompanying drawings. First of all, a first embodiment is explained. This air conditioner is composed of an outdoor unit and an indoor unit, and the following description is made about a wall-mounted type indoor unit.

(First Embodiment) Referring first to Figs. 3, 4 and 5, the internal structure of the indoor unit is explained. First, as shown in Fig. 5, an indoor-unit casing 1 of the indoor unit is made up of a body casing la, to which main components such as an indoor heat exchanger 4, a cross flow fan 9 and an electrical-equipment unit 14 are to be attached, a front grille 5 to be attached to the front face of this body casing la, and a front panel 7 to be attached to the further front face of the front grille 5, where the indoorunit casing 1 as a whole is oblong shaped with its widthwise size longer than its vertical size. Among these components, the front panel 7 is removable freely for the user, while the body casing la and the front grille 5 are unremovable for the user. Further, as shown in Figs. 3 and 4, within the indoor-unit casing 1 is provided the platefin type indoor heat exchanger 4, which is made up by lacing a front-side heat exchanger 2 and a rear-side heat -13exchanger 3 in an inverted-V shape. In this indoor-unit casing 1, as shown in Fig. 4, a top-face inlet port 6 is formed at a ceiling portion of its front grille 5, and a front-face inlet port 8 is formed in the front panel 7. In these components, the top-face inlet port 6 is formed by making the ceiling portion of the front grille 5 into a lattice shape, while the front-face inlet port 8 is formed by extending an upward-directed opening laterally over a slightly-upper central part of the front panel 7. Also, inside the inverted V of the indoor heat exchanger 4, is provided the cross flow fan 9. This cross flow fan 9, which is a so-called axial fan, is so positioned that its axial direction extends along the lengthwise direction of the indoor-unit casing 1. Then, behind the cross flow fan 9 is formed a scroll portion 10, which is smoothly connected to an outlet port 11 opened at a lower portion on the front side of the indoor-unit casing 1.

An upper wall surface 12 of the outlet port 11 is integrally formed with a drain pan 13 located below the front-side heat exchanger 2. The electrical-equipment unit 14 is disposed at a position above the outlet port 11 and on the front side of the drain pan 13, i.e. a position between the drain pan 13 and the front panel 7. Below the rear-side heat exchanger, a rear-side drain pan 15 is disposed.

-14- This indoor unit itself and the indoor-unit casing 1 are oblong shaped as shown in Figs. 1 and 2, while the front-face inlet port 8 and the outlet port 11 are formed so as to extend along the lengthwise (lateral) direction of the indoor-unit casing i. Also, the electrical-equipment unit 14 is so formed as to extend laterally along the lengthwise direction of the indoor-unit casing 1 at a position which is above the outlet port 11 and which is on the front side of the drain pan 13, as shown in Figs. 1 and 2.

Concrete structure of the electrical-equipment unit 14 is explained with reference to Figs. 6, 7 and 8.

Referring to Fig. 6, reference numeral 20 denotes an electrical-equipment casing for accommodating the electrical-equipment unit 14 therein, 21 denotes an electrical-equipment cover for covering the electricalequipment unit 14, where the electrical-equipment unit 14 is disposed between these two members 20, 21. The electrical-equipment unit 14, as shown in Fig. 8, is composed of a terminal board 22 serving as an power input section to be connected to commercial power supply (100 VAC or 200 VAC), an AC circuit section 23, a DC high-voltage circuit section 24, a DC low-voltage circuit section 25, a CPU control section 26 and a light-emitting display section 27. As shown in Figs. 6 and 7, the DC high-voltage circuit section 24 is mounted on a first PCB (Printed Circuit Board) 28, the DC low-voltage circuit section 25 is mounted on a second PCB 29, and the light-emitting display section 27 is mounted on a display board 30. Then as shown in Figs. 6 and 7, the terminal board 22, the AC circuit section 23, the DC high-voltage circuit section 24, the DC low-voltage circuit section 25 and the CPU control section 26, from right to left side as viewed in the figures, are laid out in series along the lengthwise direction of the indoor-unit casing 1, and fitted to the electricalequipment casing 20. Also, the display board 30 is fitted to the rear side of the electrical-equipment cover 21, and in this state, the electrical-equipment casing 20 is covered with the electrical-equipment cover 21. In the electrical-equipment cover 21, openings 31, 31 that allow LEDs, seven-segment LEDs (light-emitting display means), or the like of the light-emitting display section 27 to be observed from outside are formed at positions corresponding thereto.

In this electrical-equipment unit 14, for its oblong form as a whole, the first PCB 28, the second PCB 29 and the display board 30 are formed each as oblong as possible. The first PCB 28 and the second PCB 29 are connected to each other with a board-to-board connector 39 -16and without using any harness in a harnessless state) The DC high-voltage circuit section 24 provided in the first PCB 28 employs heat-generating components such as a SW transformer 41, a rectifier diode 42 and a primaryside SW device 43. These highly self-heating electrical components 41, 42, 43, as shown in Fig. 7, are disposed above the vertically extending first PCB 28, thereby accelerating the heat radiation of the electrical components 41, 42, 43 and moreover preventing the other electrical components from being affected by the heat radiation. Also, whereas the electrical-equipment unit 14 is accommodated in the electrical-equipment casing 20 and covered with the electrical-equipment cover 21 as described above, a certain gap (portion indicated by reference numeral 45 in Fig. 7) is provided as a heat radiation hole between upper part of the electrical-equipment casing and upper part of the electrical-equipment cover 21, and this gap is opened toward the front side so that air flowing along the front side acts to accelerate the heat radiation of the highly self-heating electrical components 41, 42, 43. Further, making the heat radiation hole opened toward the front side prevents the penetration of drain water and maintains the reliability of the equipment.

-17- In this air conditioner, a DCPWM type indoor-fan driving motor for driving the cross flow fan 9 is set on the right side in Fig. 1, and a flap-control motor (stepping motor) for controlling the drive of a horizontal flap is set on the left side in Fig. 1. As shown in Fig.

8, the indoor-fan driving motor 35 is powered from the DC high-voltage circuit section 24, while the flap-control motor 36 is powered from the DC low-voltage circuit section That is, as the DC high-voltage circuit section 24 is set on the right side and the DC low-voltage circuit section 25 is set on its left side as shown in Figs. 6 and 7, so the indoor-fan driving motor 35 as a high-voltage drive actuator is set on the right side and the flapcontrol motor 36 as a low-voltage drive actuator is set on its left side, similarly, so that the circuit sections 24, and the actuators 35, 36 are set as close to each other as possible.

Further, whereas the indoor unit is connected to the outdoor unit 37 as shown in Fig. 8, this connection is fulfilled with a WVVF line 38. This VVF line 38 is composed of a pair of power supply AC lines and a transmission line for internal and external transmission. This WVF line 38 as an internal-and-external connecting line is insertable from the right side in Figs. 6 and 7 and connectable to the terminal board 22. That is, the direction in which this -18- WVVF line 38 is inserted into the terminal board 22 is a direction which is the lengthwise direction of the indoorunit casing 1 and which is directed from the AC circuit section 23 toward the DC low-voltage circuit section Inserting the WVVF line 38 toward such a direction facilitates the work of inserting and connecting the VVWF line 38 itself, and moreover enables the prevention of interference between the VVF line 38 and the individual circuit sections 23, 24, 25, 26, thus facilitating the line routing work and enabling noise reduction.

The openings 31, 31 of the electrical-equipment cover 21 are observable for the user through an observation window 32 of the front grille 5 from its outside as shown in Fig. 9. It is noted here that the front panel 7 does not cover the whole front grille 5, and the front grille has a portion near its lower part exposed to outside as shown also in the figure.

In this air conditioner, as shown in Fig. 12, the electrical-equipment unit 14 is so set that a length of the electrical-equipment unit 14 along the lengthwise direction of the indoor-unit casing 1 is at least 1/2 or more of the lengthwise size LA of the indoor-unit casing 1.

This length of the electrical-equipment unit 14 is preferably as long as possible, so being set to at least 2/3 or more of the lengthwise size LA of the indoor-unit -19casing 1. Most preferably, the length of the electrical-equipment unit 14 along the lengthwise direction of the indoor-unit casing 1 is set to a length generally equal to the lengthwise size LA of the indoor-unit casing 1. Making the electrical-equipment unit 14 the longest possible or a length extremely proximate thereto like this allows its cross-sectional area to be made a minimum or a proximity thereto, which leads to a large enhancement of the degree of freedom for the position where the electrical-equipment unit 14 is placed, as well as a large reduction of ventilation resistance and the like. Thus, the indoor unit can be made more compact to a large extent and the air-conditioning performance can be improved to a large extent.

In this air conditioner, since the electricalequipment unit 14 is made up by laying out the terminal board 22, the AC circuit section 23, the DC high-voltage circuit section 24, the DC low-voltage circuit section and the CPU control section 26 in series along the lengthwise direction of the indoor-unit casing 1, the electrical-equipment unit 14 is long, narrow shaped. This eliminates the need for any special space for placing the electrical-equipment unit 14 in a side portion of the indoor-unit casing 1, which would be involved in the prior art. Therefore, the indoor unit can be reduced in its lengthwise size, so that the indoor unit can be made more compact. This means, from the opposite standpoint, that the placement spaces for the indoor heat exchanger 4 and the cross flow fan 9 can be increased in an indoor unit having the same size as conventional ones. Thus, the airconditioning performance can be improved over the prior art.

In this air conditioner, since the indoor-fan driving motor (high-voltage drive actuator) 35 is placed closer to the DC high-voltage circuit section 24, the connecting harness is shortened, allowing the construction to be simplified and the connecting and assembling work to be facilitated. Also, since the flap-control motor (lowvoltage drive actuator) 36 is placed closer to the DC lowvoltage circuit section 25, the connecting harness is further shortened, allowing the construction to be simplified and the connecting and assembling work to be further facilitated. Furthermore, the DC high-voltage circuit section 24 and the DC low-voltage circuit section 25, being taken as a unit block, are accommodated on the PCBs 28 and 29, each on one board, thus allowing the maintenance work to be facilitated.

In this air conditioner, since the highly selfheating electrical components 41, 42, 43 are placed at upper positions of the PCB 28, the heat radiation of the -21electrical components 41, 42, 43 can be accelerated, and moreover the other electrical components can be prevented from being affected by the heat radiation. Also, by making the heat radiation hole 45 opened toward the front side, it becomes possible to accelerate the heat radiation of the highly self-heating electrical components 41, 42, 43 by air flowing along the front side. Besides, since the heat radiation hole 45 is opened toward the front side, the penetration of drain water can be prevented and the reliability of the equipment can be maintained.

Also in this air conditioner, the VVF line 38 is inserted into the terminal board 22 along a direction which is the lengthwise direction of the indoor-unit casing 1 and which is directed from the AC circuit section 23 to the DC low-voltage circuit section 25. Inserting the VVF line 38 toward such a direction facilitates the work of inserting and connecting the VVF line 38 itself, and enables the prevention of interference between the WVVF line 38 and the individual circuit sections 24, 25, 26, thus facilitating the line routing work and enabling noise reduction.

In this air conditioner, the electrical-equipment unit 14 is located at a position which is above the outlet port 11 and which is on the front side of the drain pan 13.

This region is a part which needs to be a dead space for g prevention of short-circuits between outlet and inlet -22sides. Since the electrical-equipment unit 14 is placed in such a region, the space inside the indoor-unit casing 1 can be utilized further effectively. As a result of this, the indoor unit can be made even more compact, or the airconditioning performance can be further improved.

Also in this air conditioner, the electricalequipment unit 14 is accommodated within the electricalequipment casing 20, and moreover covered with the electrical-equipment cover 21. This makes it possible to prevent the electrical-equipment unit 14 from being adversely affected by the drain water in the drain pan 13, so that the electrical-equipment unit 14 can be improved in its reliability. The electrical-equipment unit 14 can also be prevented from being adversely affected by the filled water for use of checking the drainage function in the installation work, or by detergents and cleaning water in the cleaning of the indoor heat exchanger 4, so that the electrical-equipment unit 14 can be improved in reliability also in these terms. It is noted that the shielding mechanism for drain water has only to be capable of preventing the occurrence of any adverse effects such as short-circuits due to the drain water, and it is not necessarily required to completely shield the penetration of drain water, where the shielding mechanism includes such Z measures as omitting any of the electrical-equipment casing -23and the electrical-equipment cover 21 or as merely providing a partition board. Then, in this air conditioner, removing the front panel 7, the front grille and the electrical-equipment cover 21 causes the electrical-equipment unit 14 to be exposed to outside. In this state, the electrical components can be accessed for their inspection, replacement and repair from the front side, thus facilitating the parts replacement and the maintenance work.

In this air conditioner, the electrical-equipment unit 14 is equipped with the light-emitting display section 27, and this light-emitting display section 27 is placed at a position observable from outside through the observation window 32 provided on the front side of the indoor-unit casing 1. Like this, since the light-emitting display section 27 is provided integrally with the electricalequipment unit 14, lead wires or the like for electrically connecting the electrical-equipment unit 14 and the lightemitting display section 27 to each other do not need to have such a long wiring length as could be seen in the prior art, so that the wiring length can be made considerably shorter than the conventional counterpart, allowing a cost reduction. Moreover, by locating the electrical components and the light-emitting display t2 section 27 close to each other, the maintenance work can -24also be facilitated. Further, since the electricalequipment unit 14 is accommodated in the electricalequipment casing 20 and covered with the electricalequipment cover 21 so as to be formed into a single unit in a pillar shape, the air conditioner becomes easier to manufacture and handle, thus allowing cost reduction and reliability improvement.

Fig. 10 schematically shows the arrangement state of the individual circuits. As described above, the terminal board 22, the AC circuit section 23, the DC highvoltage circuit section 24 and the DC low-voltage circuit section 25 are disposed along the lengthwise direction of the indoor-unit casing 1. Fig. 11 showing modification examples thereof, Fig. 11A shows a layout suitable for products having the AC/DC converter section outside the unit, where the circuit sections of the DC high-voltage circuit section 24 and the DC low-voltage circuit section are placed along the lengthwise direction of the indoorunit casing 1. Fig. 11B shows a layout suitable for products in which step-down is fulfilled by a transformer or the like, where the circuit sections including the terminal board 22, the AC high-voltage circuit section 23, an AC low-voltage circuit section 23a and the DC lowvoltage circuit section 25 are placed along the lengthwise direction of the indoor-unit casing 1.

(Modification Example for Shape of the Electrical-Equipment Unit) In the above-described air conditioner, the electrical-equipment unit 14 is accommodated in the electrical-equipment casing 20 and covered with the electrical-equipment cover 21 so as to be formed into a pillar shape as a single unit, facilitating the manufacture and handling of the air conditioner, and moreover enabling cost reduction and reliability improvement. Otherwise, as shown in Fig. 13, the electrical-equipment unit 14 may also be implemented as a plurality of units 14a, 14b, 14c arrayed generally on a straight line. More specifically, the electrical-equipment unit 14 is made up of a plurality of PCBs, and these plurality of PCBs are mounted on the same board and electrically connected to one another. In the case where the electrical-equipment unit 14 is constructed in this way, the electrical-equipment unit 14 is preferably formed into a generally pillar shape as a whole in terms of compactness and handlability.

Furthermore, as shown in Fig. 14, the electrical-equipment unit 14 may be implemented by a plurality of units 14a, 14b, 14c, where the units 14a, 14b, 14c are arranged so as to be shifted from one another both in the lengthwise direction and in a direction crossing the lengthwise direction (air flow direction). Such a formation of the -26electrical-equipment unit 14 makes it possible to improve the degree of freedom for the selection of its arrangement position, enabling a proper arrangement according to the machine model.

The indoor unit of this air conditioner is not limited to those of the wall-mounted type and includes such various types of ones as floor-setting type and ceilingburied type. It follows therefore that the term, lengthwise direction, may mean a right-and-left direction as viewed from the user, and may also mean an up-and-down direction or a horizontal direction.

Claims

1. An air conditioner having an electrical-equipment unit (14) placed within an indoor-unit casing wherein the electrical-equipment unit (14) comprises a high-voltage circuit section (24) and a low-voltage circuit section arranged in this order, as viewed from a power input section (22) side, along a lengthwise direction of the indoor-unit casing (1)

2. The air conditioner according to Claim i, wherein an AC circuit section a DC high-voltage circuit section (24) and a DC low-voltage circuit section (25) are placed in this order as viewed from an AC power input section (22) side.

3. The air conditioner according to Claim i, wherein an AC high-voltage circuit section an AC low-voltage circuit section (23a) and a DC low-voltage circuit section are placed in this order as viewed from an AC power input section (22) side.

4. The air conditioner according to Claim 1, wherein a DC high-voltage circuit section (24) and a DC low-voltage circuit section (25) are placed in this order as viewed from a DC power input section. The air conditioner according to any one of Claims 1 to 4, wherein the power input section (22) is -28- provided on one side within the indoor-unit casing on which a high-voltage drive actuator (35) is placed.

6. The air conditioner according to Claim 5, wherein a low-voltage drive actuator (36) is provided on one side within the indoor-unit casing on which the low-voltage circuit section (25) is placed, the one side being opposite to a side on which the high-voltage drive actuator (35) is provided.

7. The air conditioner according to Claim 6, wherein the high-voltage drive actuator (35) is an indoor-fan driving motor and the low-voltage drive actuator (36) is a flap-control motor.

8. The air conditioner according to any one of Claims 1 to 7, wherein a singularity or plurality of the circuit sections (24) (25) as a unit block are accommodated on one printed circuit board (28) and a plurality of the printed circuit boards (28) (29) are arrayed along a lengthwise direction of the indoor-unit casing (1)

9. The air conditioner according to any one of Claims 1 to 8, wherein a lengthwise size of a space where the electrical-equipment unit (14) is placed is 1/2 or more of a lengthwise size of the indoor-unit casing (1) The air conditioner according to any one of Claims 1 to 9, wherein the electrical-equipment unit (14) i is placed at a position above an outlet port (11) of the -29- indoor-unit casing and over a laterally extending region located between a drain pan (13) of an indoor heat exchanger and a front panel of the indoor-unit casing (1)

11. The air conditioner according to Claim wherein within the electrical-equipment unit highly self-heating electrical components (41) (42) (43) are placed on an upper side of the printed circuit board (28).

12. The air conditioner according to Claim 10 or 11, wherein a heat radiation hole (45) for cooling the electrical-equipment unit (14) is opened toward the front side.

13. The air conditioner according to any one of Claims 1 to 12, wherein the power input section (22) is given by a terminal board and an insertion direction of a VVF line (38) in this terminal board is set along the lengthwise direction of the indoor-unit casing (1)

14. The air conditioner according to Claim 13, wherein the insertion direction of the WVF line (38) is directed from the power input section (22) toward the DC low-voltage circuit section