JP2000274807A - Indoor unit and air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a unit size in a compact manner with performance of indoor performance at least maintained. SOLUTION: This indoor unit 10 comprises an indoor fan to suck indoor air through an air inlet 12b and supply air through an air outlet 12c, an indoor heat-exchanger 13 to perform heat-exchange between indoor air and a refrigerant supplied from an outdoor unit, an indoor unit control part consisting of various electric circuit elements and a casing 10A to contain the apparatuses described above. A centrifugal fan 14 is used in the indoor fan and the centrifugal fan 14 is installed in an inclination state in the casing 10A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor unit and an air conditioner for providing a comfortable indoor environment by heating or cooling, and more particularly to a technology for providing a compact and highly efficient indoor unit.

[0002]

2. Description of the Related Art An air conditioner is composed of two major components, an indoor unit and an outdoor unit. Each of these units includes an indoor heat exchanger and an outdoor heat exchanger that exchange heat between the refrigerant and the indoor air and between the refrigerant and the outdoor air.

[0003] These indoor heat exchangers and outdoor heat exchangers are:
In addition, components such as a compressor and an expansion valve are added to constitute a refrigerant circuit. Refrigerant physically circulates through this circuit, and follows the circulating process of changing the state of high-temperature and high-pressure gas, low-temperature and low-pressure gas, high-temperature and high-pressure liquid, and low-temperature and low-pressure liquid. . The cooling and heating of the room is directly realized by heat exchange between the refrigerant in the indoor heat exchanger and room air.

By the way, during the heating operation, the gas refrigerant, which has been converted into a high-temperature and high-pressure gas by the compressor, is sent to the indoor heat exchanger.
This is realized by performing heat exchange between the refrigerant and room air. During the cooling operation, the high-temperature and high-pressure gaseous refrigerant is sent to the outdoor heat exchanger to exchange heat with the outdoor air to produce a high-temperature and high-pressure liquid refrigerant, which is further passed through an expansion valve to lower the temperature and lower the pressure, thereby reducing This is realized by sending the refrigerant to a heat exchanger and performing heat exchange between the refrigerant and room air.

[0005]

By the way, in the above-mentioned conventional indoor unit, as shown in FIG. 3, a once-through fan is used as the indoor fan 4 for sucking room air from the inlet 2 and blowing it out from the outlet 3. Commonly used. Since the once-through fan has low static pressure and low efficiency, there is a problem that the pressure loss in the indoor heat exchanger cannot be increased so much. Moreover, the indoor unit 1 using the once-through fan has a feature of the once-through fan that the ratio of the blade width to the outer diameter is large, so that the thickness (depth) W1 of the indoor unit 1 is maintained while securing the desired suction and blowing performance. There are limits to thinning. However, for the indoor unit 1 to be installed and used indoors, it is extremely important to consider the compatibility with the interior of the room in order to enhance the marketability. Therefore, it is desired to make W1 as thin as possible and to make the entire indoor unit compact.

From such a background, in order to make the indoor unit 1 thin, a centrifugal fan may be used instead of the once-through fan.
And JP-A-56-168722. In such prior art, the main purpose is to make the indoor unit thinner, so that the centrifugal fan is installed vertically in each case. Therefore, it is difficult to blow out the conditioned air horizontally even if a flap is used because the opening is narrow (Japanese Patent Application Laid-Open No. H10-122589), or a large ventilation path is required to direct the wind direction to the front. No. 56-168722), which is a factor that hinders downsizing of the entire indoor unit.

The present invention has been made in view of the above circumstances, and has been made possible by making it possible to increase the density of an indoor heat exchanger (reducing high pressure loss), and to improve the air conditioning blown from an indoor fan. It is an object of the present invention to provide an indoor unit and an air conditioner in which the entire indoor unit is made thin and compact by eliminating a ventilation path for blowing air toward the front.

[0008]

The present invention employs the following means in order to solve the above-mentioned problems. The indoor unit according to claim 1, wherein an indoor fan for sucking indoor air from an inlet and blowing out from an outlet, and indoor heat exchange for performing heat exchange between the indoor air and a refrigerant supplied from an outdoor unit. And an indoor unit control section composed of various electric circuit elements, and a casing for accommodating each of these devices. A centrifugal fan is used for the indoor fan, and the centrifugal fan is installed at an angle. It is assumed that.

According to such an indoor unit, the use of a centrifugal fan makes it possible to increase the density of the heat exchanger, and the inclined installation of the centrifugal fan makes it possible to blow out horizontally so that the outlet is located in front. A ventilation path for directing is not required.

In the air conditioner according to the present invention, an outdoor heat exchanger for exchanging heat between the outside air and the refrigerant, and a high-temperature and high-pressure gas refrigerant is sent to the outdoor heat exchanger or the indoor heat exchanger. An outdoor unit including a compressor, an outdoor fan that sucks the outside air and passes through the outdoor heat exchanger, an outdoor unit control unit including various electric circuit elements, and a housing that stores these devices. A unit, an indoor fan for sucking indoor air from the suction port and blowing it out from the outlet, an indoor heat exchanger for exchanging heat between the indoor air and the refrigerant supplied from the outdoor unit, and various electric circuit elements. An indoor unit, comprising: an indoor unit control section comprising: a casing for accommodating each of these devices; and a centrifugal fan used as the indoor fan and an indoor unit provided with the centrifugal fan inclined. It is an feature.

According to such an air conditioner, the density of the heat exchanger is increased by using a centrifugal fan, and the ventilation path for directing the blowing direction to the front is not required by the inclined installation of the centrifugal fan. Thus, it is possible to maintain the performance of at least the indoor unit and make the indoor unit compact.

The air conditioner according to claim 3 is characterized in that the centrifugal fan is inclined upward from a vertical plane.

According to such an air conditioner, conditioned air can be blown toward the front from the outlet provided on the lower surface of the indoor unit, and a ventilation path for directing the blow direction to the front becomes unnecessary.

The air conditioner according to a fourth aspect is characterized in that the inclination angle of the centrifugal fan is in a range of 10 degrees to 15 degrees from a vertical plane or in the vicinity thereof.

According to such an air conditioner, it is possible to achieve a proper balance between the front blowout that does not require a ventilation passage and the compactness of the indoor unit. That is, when the inclination angle is larger than 15 degrees, the thickness (depth) of the indoor unit becomes too large, and when the inclination angle is smaller than 10 degrees, it becomes difficult to blow out the front.

The air conditioner according to a fifth aspect is characterized in that the indoor heat exchanger is installed obliquely so as to face the centrifugal fan.

According to such an air conditioner, the effective area of the indoor heat exchanger can be increased as compared with a case where the air conditioner is installed vertically.

According to a sixth aspect of the present invention, there is provided an air conditioner, wherein a pipe passage is provided at a lower portion of a rear surface of the centrifugal fan inclined upward.

According to such an air conditioner, since the pipe passage is formed in the lower part of the rear surface of the centrifugal fan in the indoor unit, the layout for compact design becomes easy.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an indoor unit and an air conditioner according to the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing the overall configuration of the air conditioner. The air conditioner includes an indoor unit 10 and an outdoor unit 30. The indoor unit 10 and the outdoor unit 30 are connected by a refrigerant pipe 40 through which the refrigerant flows, an electric wiring (not shown), and the like. Refrigerant piping 4
0 are provided, and the refrigerant flows from the indoor unit 10 to the outdoor unit 30 on one side and flows from the outdoor unit 30 to the indoor unit 10 on the other side.

In the indoor unit 10, a base 11 and a front panel 12 are integrally connected to form a casing 10A, in which various devices described later are housed in the casing 10A. The base 11 is provided with various devices such as a fin tube type indoor heat exchanger 13 and a centrifugal fan 14. The base 11 includes an indoor unit control unit 15 composed of various electric circuit elements in order to perform various operation controls and the like regarding the other indoor units 10.
Is provided. The indoor unit controller 15 includes:
As a means to display the operation status and error mode,
A suitable indicator 15a is provided. The indicator 15a can be visually confirmed from the outside by a see-through portion 12a provided on the front panel 12. A mounting plate (not shown) is provided at the rear of the base 11 as necessary. The mounting plate is used, or the mounting means (not shown) provided on the back surface of the casing 10A is used to install the indoor space. The unit 10 can be installed on a wall or the like in a room.

The front panel 12 is formed with a suction grill (suction port) 12b. Indoor air (room air)
Is sucked into the indoor unit 10 from the front of the unit by the suction grill 12b. Incidentally, an air filter 16 is provided behind the suction grill 12b, and functions to remove dust such as sucked air. An outlet 12c is formed below the front panel 12, from which warmed or cooled air is blown out. The air suction and the air blowing are performed by the rotation of the centrifugal fan 14.

The above-described indoor unit 10 includes a remote controller 50 as an operation section for performing various driving operations. The remote controller 50 is provided with various switches and the like, and can transmit an operation signal of the air conditioner to a receiving unit (not shown) of the indoor unit control unit 15. Note that the operation of the air conditioner can be partially performed by switches (not shown) provided at appropriate places in the indoor unit.

The outdoor unit 30 is provided with an outdoor heat exchanger 31, a propeller fan 32, a compressor 33, an outdoor unit control section 34, etc. in a housing 30a. The outdoor heat exchanger 31 is configured by a refrigerant pipe having a large number of fins around it, and realizes heat exchange between the refrigerant and outdoor air.

The propeller fan 32 has a function of sucking outside air into the housing 30a. This propeller fan 3
2 operates, it is possible to generate an external air flow that passes through the outdoor heat exchanger 31 and enters the housing 30a and escapes to the front of the housing. The heat is taken into the housing 30a to improve the heat exchange efficiency of the outdoor heat exchanger 31.

A finger 30b and a fan guard 30c are provided on each surface of the housing 30a where the outdoor heat exchanger 31 and the propeller fan 32 face the outside. The fingerings 30b are provided so that the fins are not damaged by an unexpected external impact. Fan guard 30c,
Similarly, one purpose is to protect the propeller fan 32 from external impact and to prevent dust and the like contained in the outside air from being taken into the housing 30a.

The compressor 33 converts a low-temperature and low-pressure gaseous refrigerant into a high-temperature and high-pressure gaseous refrigerant and discharges the refrigerant. The compressor 33 plays the central role in the components constituting the refrigerant circuit. Incidentally, the refrigerant circuit is, in addition to the compressor 33, the indoor heat exchanger 13, the outdoor heat exchanger 31,
A circuit that roughly includes a refrigerant pipe 40, an expansion valve, and a four-way valve (both expansion valves and a four-way valve are not shown) for regulating the flow direction of the refrigerant, and circulates the refrigerant between the indoor unit 10 and the outdoor unit 30. It is.

The outdoor unit control section 34 controls the operation of the propeller fan 32, the compressor 33, and other various devices provided in the outdoor unit 30, and is composed of various electric circuit elements. .

The outdoor unit 30 includes a housing 3 in addition to the above.
A pedestal 30d is provided to support Oa and to avoid the influence of external vibration and the like. The compressor 3
In order to easily carry out maintenance and the like of 3, serviceability is also taken into consideration, for example, by providing a removable member 30 e on the wall of the housing 30 a near the compressor 33.

In the following, the operation of the air conditioner having such a configuration will be described for each of the heating operation and the cooling operation. First, during the heating operation, the refrigerant converted into a high-temperature and high-pressure gas by the compressor 33 is supplied to the refrigerant pipe 4.
0, and is sent to the indoor heat exchanger 13 of the indoor unit 10. In the indoor unit 10, heat is given to indoor air taken in from the suction grill 12 b by the centrifugal fan 14 from a high-temperature and high-pressure gas refrigerant passing through the indoor heat exchanger 13. As a result, warm air is blown from the outlet 12c below the front panel 12. At the same time, the high-temperature and high-pressure gas refrigerant is condensed and liquefied in the indoor heat exchanger 13, and becomes a high-temperature and high-pressure liquid refrigerant.

The high-temperature and high-pressure liquid refrigerant is again supplied to the refrigerant pipe 4
0 through the outdoor heat exchanger 31 in the outdoor unit 30
Sent to In the outdoor unit 30, the propeller fan 3
The high-temperature and high-pressure liquid refrigerant passing through the outdoor heat exchanger 31 takes away heat from the new outdoor air taken into the housing 30a by 2. As a result, the high-temperature and high-pressure liquid refrigerant evaporates and becomes a low-temperature and low-pressure gas refrigerant. This is sent to the compressor 33 again, and the above process is repeated.

Next, during the cooling operation, the refrigerant flows through the refrigerant circuit in a direction opposite to the above. That is, the refrigerant converted into a high-temperature and high-pressure gas by the compressor 33 passes through the refrigerant pipe 40 and is sent to the outdoor heat exchanger 31, where the refrigerant is condensed and liquefied by applying heat to the outdoor air to become a high-temperature and high-pressure liquid refrigerant. . The high-temperature and high-pressure liquid refrigerant passes through an expansion valve (not shown) to become a low-temperature and low-pressure liquid refrigerant, and is sent to the indoor heat exchanger 13 again through the refrigerant pipe 40. The low-temperature and low-pressure liquid refrigerant here takes heat from room air to cool the room air, and the refrigerant itself evaporates and becomes a low-temperature and low-pressure gas refrigerant. This is compressor 3 again
3 and the above process is repeated.

These operations are performed by the indoor unit control unit 15 and the outdoor unit 30 housed in the indoor unit 10.
It is controlled by the outdoor unit control unit 34 housed therein cooperating.

Hereinafter, the characteristic portions of the present invention will be described. As described above, in this indoor unit 10,
As shown in FIG. 2, the centrifugal fan 14 having a high static pressure and a high efficiency is used, and is installed in the casing 10A in a state where the centrifugal fan is inclined slightly upward from a vertical plane. In addition, the front surface of the centrifugal fan 14 is provided with the indoor heat exchanger 13 similarly inclined.
Are installed substantially parallel to each other.

The centrifugal fan 14 rotates using a motor 14a disposed behind the fan as a driving force, and the front surface of the fan serves as a suction port. Further, the outlet of the centrifugal fan 14 is provided below the fan rotation surface, and this is
To the outlet 12c. This outlet 12c
Is provided with a flap 17 which can swing up and down, and the angle of the flap 17 can adjust the blowing angle of the conditioned air. That is, the room air before the air conditioning sucked by the centrifugal fan 14
After being sucked from the filter and passing through the filter 16 and the indoor heat exchanger 13, the air is compressed by the centrifugal fan 14 and
It is blown out from 2c.

At this time, since the centrifugal fan 14 is installed so as to be inclined upward, the outlet 12 provided below the fan is directly blown out from the front without cooperating with the flap 17 without forming a ventilation path. Becomes possible. That is, when the centrifugal fan 14 is installed vertically, a ventilation path for directing the blow-out port directed directly downward to the front is required, and an extra space is required by that amount. Accordingly, the size of the indoor unit 10 can be reduced. By installing the centrifugal fan 14 at an angle, a space having a substantially triangular cross section is formed behind the fan. As a result, there is room in the installation space for the motor 14a, and it is not necessary to use a high-cost thin motor. That is, the use of a general motor is advantageous in terms of cost.

The tilt angle θ of the centrifugal fan 14 (see FIG. 2B) is preferably set in the range of 10 to 15 degrees from the vertical plane. The purpose of limiting the range of the inclination angle θ in this manner is to appropriately balance the compactness of the indoor unit 10 with the above-described front blowing function. If θ is less than 10 degrees, the outlet 12c is directed substantially downward, so that the function of the front blowout becomes insufficient, and it is necessary to install a ventilation path, which is an obstacle to downsizing. Conversely, when θ is larger than 15 degrees, the thickness W2 of the indoor unit 10 (see FIG. 2B) increases, so that the projection amount from the wall 18 increases in a normal installation method. Not a very good interior.

The indoor heat exchanger 13 is also installed so as to face the centrifugal fan 14 and to be inclined upward within a range of 10 to 15 degrees from a vertical plane. Therefore, if the vertical (up and down) dimensions of the indoor unit 10 are the same, the effective area of the indoor heat exchanger 13 can be increased by the amount of the inclination. Increasing the effective area of the indoor unit 13 leads to improvement in heat exchange efficiency, which is effective for improving the performance of the indoor unit 13.

As described above, when the centrifugal fan 14 is installed in the casing 10A in a state in which the centrifugal fan 14 is inclined upward, a space that forms a piping passage 19 between the centrifugal fan 14 and the substantially vertical casing wall surface is provided at the lower rear portion. A portion is formed (see FIG. 2B). The piping passage 19 is located at a position suitable as a space for passing piping such as the refrigerant pipe 20 in the unit and the drain hose 21. Therefore, the layout of the indoor unit 10 requiring a compact design is designed to be compact. Extremely effective. Reference numeral 20a in the figure is a heat insulating material that covers the refrigerant pipe 20 in the unit.

As described above, the centrifugal fan 1 of high static pressure and high efficiency is used as the indoor fan installed in the indoor unit 10.
The use of No. 4 makes it possible to secure sufficient blowing performance, so that the indoor unit 10 can use the indoor heat exchanger 13 having a higher density (high-pressure loss). Therefore, the size of the indoor heat exchanger 13 can be reduced, and as a result, the indoor unit 10 that houses the indoor heat exchanger 13 as a component can be formed into a compact shape while maintaining the performance.

Since the centrifugal fan 14 is installed inclined upward, horizontal blowout can be easily performed. Therefore, a ventilation passage is provided to guide the air-conditioned air outlet 12c toward the front. Is unnecessary, and the indoor unit 10 can also be made compact by this. When the angle of the flap 17 is set to be horizontal, the blowout direction is slightly forward, so that there is an advantage that the opening area of the blowout port 12c can be larger than that of the conventional structure in which the blowout direction without a ventilation path is in the vertical direction. is there. And, the performance of the indoor unit 10 is maintained, and
Since it becomes possible to have a compact shape, it becomes possible to provide the indoor unit 10 with increased consistency with the interior. In addition, the indoor unit 10 having high compatibility with the interior improves the commerciality of the air conditioner as a result.

Further, the inclined arrangement of the centrifugal fan 14 provides a margin in the installation space for the motor 14a for driving the fan, so that it is not necessary to use an expensive thin motor, which is very advantageous in terms of cost. An ordinary general-purpose motor can be used, and a space serving as a pipe passage 19 can be secured at the lower rear portion of the centrifugal fan 14, so that the layout in the indoor unit 10 is facilitated.

Furthermore, the centrifugal fan 14 which is arranged in an inclined manner
Since the indoor heat exchanger 13 is also inclined so as to face, the effective area of the indoor heat exchanger 13 is increased as compared with the case where the indoor heat exchanger 13 is installed vertically, and as a result, the heat exchange performance can be improved. Therefore, if the same performance is ensured, the indoor heat exchanger 13 can be downsized.

In addition, the use of the centrifugal fan 14 with high static pressure and high efficiency provides a margin in terms of pressure loss, so that an air purifying function can be newly added or It is easily possible to further enhance a certain air cleaning function. In this case, by arranging the centrifugal fan 14 and the indoor heat exchanger 13 in an inclined manner, the effective area of the air filter 17 and the air cleaning device (not shown), which are often arranged in parallel with them, can be increased. This is also advantageous for enhancing the air purifying function. In the indoor unit 10 described above,
Since the air inlet 12b for sucking room air or the air outlet 12c for blowing out conditioned air is not provided on the upper surface of the casing 10A, the indoor unit 10 can be installed up to the very edge of the ceiling. Therefore, it is advantageous in terms of effective use of the indoor space and consistency with the interior.

In the above description, the centrifugal fan 14 and the indoor heat exchanger 13 are inclined upward with respect to the vertical plane. However, the inclination is not necessarily limited to the upward depending on the installation location and application. Rather, it goes without saying that it can be appropriately changed together with the position of the outlet 12c. In addition, in the case of the general indoor unit 10 installed in the upper part of the indoor wall surface, the arrangement facing upward with respect to the vertical plane is most suitable.

[0046]

According to the indoor unit and the air conditioner of the present invention, the following effects can be obtained. (1) By using a high static pressure and high efficiency centrifugal fan as an indoor fan, it becomes possible to use a heat exchanger with higher density (higher pressure loss) than before in the indoor unit. Therefore, the heat exchanger can be reduced in size, and as a result, the indoor unit accommodating the heat exchanger as a component can have a compact shape while maintaining its performance. (2) By installing the centrifugal fan in an upwardly inclined state, horizontal blowout becomes possible, and as a result, there is no need for a ventilation path for directing the air-conditioned air outlet to the front. The unit can be made compact. Further, when the flap is leveled, the opening area of the outlet can be made larger than that of a unit having a conventional structure having no ventilation path. (3) Since the performance of the indoor unit can be maintained and a compact shape can be provided, it is possible to provide an indoor unit with increased consistency with the interior. Productivity can be improved. (4) Due to the inclined arrangement of the centrifugal fan, there is a margin in the installation space for the motor for driving the fan, so that it is not necessary to use an expensive thin motor, which is advantageous for cost reduction. (5) With the upwardly inclined arrangement of the centrifugal fan, a space serving as a pipe passage can be secured at the lower rear portion of the centrifugal fan, so that the layout in the indoor unit requiring a compact design is facilitated. (6) Since the indoor heat exchanger is also inclined so as to face the inclined centrifugal fan, the effective area of the indoor heat exchanger is increased as compared with the vertical installation, and as a result, the heat exchange performance can be improved. . (7) By using a high-static-pressure, high-efficiency centrifugal fan, there is a margin in terms of pressure loss, so that the air filter and the air cleaning function can be strengthened. In this case, by arranging the centrifugal fan and the indoor heat exchanger in an inclined manner, the effective area of the air filter and the air cleaning device can be increased, which is advantageous in enhancing the air cleaning function. (8) Since there is no indoor air suction or air-conditioning air blowing from the upper surface of the indoor unit, the indoor unit can be installed up to the ceiling surface.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional perspective view showing an embodiment of an outdoor unit and an air conditioner according to the present invention.

FIGS. 2A and 2B are diagrams showing a schematic configuration of an indoor unit according to the present invention, wherein FIG. 2A is a front view showing a state in which a front panel is removed, and FIG.

FIG. 3 is a cross-sectional view showing a schematic configuration of an indoor unit as a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Indoor unit 10A Casing 11 Base 12 Front panel 12b Suction grill (suction port) 12c Outlet 13 Indoor heat exchanger 14 Centrifugal fan (fan) 15 Indoor unit control part 16 Air filter 17 Flap 19 Pipe passage 20 Unit refrigerant pipe 30 Outdoor unit 30a Housing 31 Outdoor heat exchanger 32 Propeller fan (Outdoor fan) 33 Compressor 34 Outdoor unit control unit 40 Refrigerant piping 50 Remote controller (Operation unit)

Claims (6)

[Claims] 1. An indoor fan for sucking indoor air from an inlet and blowing it out from an outlet, an indoor heat exchanger for exchanging heat between the indoor air and a refrigerant supplied from an outdoor unit, An indoor unit, comprising: an indoor unit control section comprising a circuit element; and a casing for accommodating each of these devices, wherein a centrifugal fan is used as the indoor fan and the centrifugal fan is installed at an angle. 2. An outdoor heat exchanger for performing heat exchange between outside air and a refrigerant, a compressor for sending a high-temperature and high-pressure gaseous refrigerant to the outdoor heat exchanger or the indoor heat exchanger, and An outdoor unit that includes an outdoor fan that allows the outdoor heat exchanger to pass therethrough, an outdoor unit control unit that includes various electric circuit elements, and a housing that stores these devices. An indoor fan for sucking in and blowing out from the outlet, an indoor heat exchanger for exchanging heat between the indoor air and the refrigerant supplied from the outdoor unit, and an indoor unit control unit including various electric circuit elements, An air conditioner, comprising: a casing accommodating each of the above devices; and an indoor unit using a centrifugal fan as the indoor fan and tilting and installing the centrifugal fan. 3. The air conditioner according to claim 2, wherein the centrifugal fan is inclined upward from a vertical plane. 4. The air conditioner according to claim 3, wherein an inclination angle of the centrifugal fan is in a range of 10 to 15 degrees from a vertical plane. 5. The air conditioner according to claim 2, wherein the indoor heat exchanger is installed obliquely so as to face the centrifugal fan. 6. The air conditioner according to claim 3, wherein a pipe passage is provided at a lower portion of a rear surface of the centrifugal fan inclined upward.