JPH0336433A - Air conditioner - Google Patents

Abstract

PURPOSE:To improve the heat exchange efficiency at an indoor heat exchanger by providing a means for a supply-air feedback whereby part of the air sent by an indoor fan is returned to the air inlet and by providing a first control means by which, at the start-up of air-conditioning operation, the means for supply-air feedback is actuated and part of the air sent by an indoor fan is returned to the air inlet. CONSTITUTION:At the start-up of air-conditioning operation, a means-for-supply- air-feedback 31 is actuated so that an outlet 24 is fully closed by an outlet louver 32 and an inlet to a return-air passageway 33 is fully opened by a valve 34. By the operation of an indoor fan 30 most of air sucked into a fan casing 26, as air to be sent through an outlet 24, is returned through a return-air passageway 33 upstream to an air filter 28. Therefore, the air in the fan casing 26 circulates in a loop through the air filter 28 and an indoor heat exchanger 29. As a result, molds, dust, etc. which have entered the fan casing 26 or have been produced therein circulate with the circulating air in the fan casing 26 and are captured repetitively by the air filter 28, and the air undergoes repeated heat exchange by the indoor heat exchanger 29.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention aims to improve dust collection efficiency and improve comfort by capturing dust such as dust and mold adhering to the inside of an indoor unit. Regarding air conditioners.

(Prior Art) Generally, this type of air conditioner has an indoor unit installed indoors and an outdoor unit installed outdoors.The indoor unit is a wall-mounted unit configured as shown in Fig. 9. There is a type.

This indoor unit 1 has an inlet 3 and an outlet 4 disposed vertically in the figure on the front surface of a front panel 2, and a rear plate main body 5 is attached and fixed to a required mounting wall.

The suction port 3 and the blowout port 4 are the ventilation I inside the fan casing 6.
In this ventilation passage 7, an indoor heat exchanger 8ε and an indoor fan 9 consisting of a cross-flow fan are arranged in front and behind each other.

The indoor heat exchanger 8 is connected sequentially and in a loop to a compressor, a four-way valve, an outdoor heat exchanger, a pressure reducer such as a capillary tube, etc. through refrigerant piping (not shown), and is part of a closed refrigeration cycle that circulates the refrigerant. It consists of

When the indoor fan 9 is operated, the indoor fan 9 circulates air in an air-conditioned space such as a room into the room 111 as shown by the large arrow in the figure.

That is, as the indoor fan 9 rotates, air from an air-conditioned space such as a room is sucked inward through the suction port 3, filtered by the air filter 10, and then heat exchanged by the indoor heat exchanger 8, resulting in cool air or Warm air is blown out from the air outlet 4 to an air-conditioned space such as outdoors to cool or heat the room.

(Problem to be Solved by the Invention) However, in such a conventional indoor l111, dust such as dust and mold adhering inside the fan casing 6 on the downstream side of the air filter 10 is released from the air outlet 4 when the air conditioning operation starts. It may be released indoors and contaminate indoor air.

That is, in recent years, purification of indoor air has been attracting attention from the viewpoint of health and hygiene. Some are even treated with antibacterial treatment.

However, in this antibacterial treatment method, although the antibacterial agent is effective on the surface of the air filter 10, etc., the antibacterial effect is reduced when mold, etc. accumulates on this outer surface and further adheres to the upper layer. do.

Further, since there is no means for capturing dust such as mold and dust, there is a possibility that the dust is discharged into the room from the air outlet 4 by the air blowing from the indoor fan 9 and contaminates the indoor air.

Therefore, for example, it may be possible to install an air filter for V1m around the air outlet 4, but in this case, the air filter becomes ventilation resistance, significantly increases the air flow, and deteriorates the air conditioning capacity. There is a problem.

As shown in FIG. 10, the amount of dust emitted is large at the start of air conditioning operation, and gradually decreases as the operating time passes.

When the chamber load is small, the compressor is inverter 111iIll to lower the heat radiation temperature of the indoor heat exchanger 8, so in this case, the indoor heat exchanger 8, which has lowered its temperature, is heated, The temperature of the air blown out from the air outlet 4 decreases, giving the user a feeling of draft, which may cause discomfort.

Therefore, the present invention has been made in consideration of the above-mentioned circumstances, and its object is to provide an air conditioner that can both reduce the amount of dust blown out from the air outlet and improve comfort.

[Structure of the invention]

(Means for Solving the Problems) The present invention is configured as follows in order to achieve the above object.

That is, the present invention has a suction port that sucks air from an air-conditioned space and Il! a ventilation passage that communicates with an outlet that blows out air;
In this air conditioner having an air filter, an indoor heat exchanger, and an indoor fan interposed in the middle of the ventilation path, there is provided an air return means for returning at least a part of the air from the indoor fan to the suction port side. It is characterized by having been established.

Further, at the start of air conditioning operation, the air return means is activated to return at least a portion of the air from the indoor fan to the suction port. It is characterized in that it is provided with an I1m means.

Furthermore, the temperature of the indoor heat exchanger is detected, and when the detected temperature is lower than the setting W1, the air return means is activated,
The present invention is characterized in that a second intake means 3111 is provided for returning at least part of the air blown from the ventilation fan to the suction port side.

(Function) At the time of start-up of air conditioning operation, the air return means is operated by the first W suppressor.

For this reason, at least a portion of the air blown by the indoor fan and which should be blown out from the air outlet is returned to the suction port.

The blown air returned to the suction port side is sucked into the ventilation passage again, passes through the air filter and the heat exchanger, and flows through the ventilation passage.

Therefore, dust, mold, and other particles in this blown air are repeatedly captured and purified by the air filter, and are repeatedly heat-exchanged in the indoor heat exchanger, after which they are blown out from the air outlet into the room, etc. For this reason, according to the present invention, at least a part of the air blown into the room improves the efficiency of capturing dust, mold, and other dust, improves the purification of the air, and improves the purification of the air. heat is exchanged again.

It is possible to improve comfort by suppressing the draft feeling.

Further, when the second control means detects that the temperature of the indoor heat exchanger has fallen below the set temperature due to a reduction in the heating load or the start of air conditioning operation, for example, the second control means controls the European style return. The means are activated.

As a result, at least a part of the European air is returned to the suction port side, and as described above, the air filter and the indoor heat exchanger are ventilated again and circulated in the ventilation duct, so the air filter again removes the dust f1m! The dust is captured, heat exchanged again in the indoor heat exchanger, and then blown out from the air outlet.

Therefore, according to the present invention, it is possible to improve the efficiency of trapping dust and improve both the purification of the blown air and the comfort.

(Example) An actual flow example of the present invention will be described below based on FIGS. 1 to 8.

Note that common parts in FIGS. 1 to 8 are denoted by the same reference numerals.

FIG. 1 is a 111 sectional view of an embodiment in which the present invention is applied to, for example, a wall-mounted indoor unit 21, and in the figure,
The indoor unit 21 has an inlet 23 and an outlet 24 disposed vertically in the figure on a plane 'm' of a corner panel 22, and a rear plate main body 25 is attached and fixed to a required mounting wall.

The suction port 23 and the blowout port 24 communicate with each other through a ventilation passage 27 in the fan casing 26, and this ventilation passage 27 has an air flow of 2N above the airflow direction indicated by the arrow in the figure. An air filter 28, an indoor heat exchanger 29, and an indoor fan 30 consisting of a cross-flow fan are arranged in this order from the side toward the downstream side.

The indoor heat exchanger 29 is connected sequentially and in a loop to an inverter-driven compressor with variable capacity (not shown), a four-way valve, an outdoor heat exchanger, a pressure reducer such as a capillary tube, etc., through refrigerant piping (not shown), and is connected in a loop shape to It forms part of a closed refrigeration cycle that circulates reversibly.

When the indoor fan 30 is operated, the indoor fan 30 causes air in an air-conditioned space such as a room to circulate through the indoor unit 21 as shown by the large arrow in the figure.

That is, as the indoor fan 30 rotates, air from an air-conditioned space such as a room is sucked inward through the suction port 23, dust and other particles are captured and filtered by the air filter 28, and further, the indoor heat exchanger 29 The cool air or warm air is blown out from the air outlet 24 into an air-conditioned space such as a room, thereby cooling or heating the room.

The ventilation passage 27 is provided with an air return means 31 around the air outlet 24, and the air return means 31 allows at least a part of the air to be blown out from the air outlet 24 into the room as shown by the small arrow. The air is returned to the ventilation passage 27 on the upstream side of the air filter 28.

The air return means 31 is an air outlet louver 3 that opens and closes the air outlet 24.
2, a return Jl path 33 that communicates the air outlet 24 and the suction port 23 side in the ventilation path 27, and an inlet end of this return air path 33 at the bottom in the figure. The opening/closing valve 34 controls the opening/closing of the opening/closing valve 34 and the blow-off louver 32, and a first Illmm (not shown) controls the opening/closing of the opening/closing valve 34 and the blow-off louver 32.

The blowout louver 32 is configured to control the degree of the blowout opening 24 from fully open to fully open by rotating around its rotation axis 32a.

The 1lllIrtI valve 34 moves from the fully open position where the inlet end of the return air passage 33 is fully opened to the outer bottom of the drain pan 35 that receives condensate condensed in the indoor heat exchanger 29, to the fully r! I
The slider valve body 34a slides to the fully open position, and the slider valve body 34a is moved between the fully open position and the fully open position. A two-way coil spring 34b made of a shape memory alloy is provided, which has expansion and contraction positions arranged so as to cause the expansion and contraction to occur.

The first V3M device (not shown) is configured to operate the air return means 31 at the time of startup of air conditioning operation (start 11J).

That is, as shown in FIG. 10, at the start of air conditioning operation in which a large amount of dust is emitted, the first II controller controls the rotation angle of the blowout louver 32 so as to fully open the blowout port 24, as shown in FIG. At the same time, the coil spring 34b is electrically heated and contracted so as to retract the slider valve body 34a to a fully open position where the inlet end of the return air passage 33 is fully opened.

Therefore, at the start of air conditioning operation, as shown in FIG. While returning the air to the ventilation path 27 of the suction port 23, it is possible to prevent the air from blowing into the room at the start of operation, which often contains multicolored dust.

In addition, after the required time has passed from the start of air conditioning operation, the 10th
As shown in the figure, the amount of dust emitted gradually decreases, so the first ! The IIwJ device stops the operation of the air return means 31 after the required start-up time of the air conditioning operation has elapsed.

That is, as shown in FIG. 3, the first controller controls the rotation of the blow-off louver 32 so as to fully open the blow-off port 24, and controls the slider so as to fully close the inlet end of the return air passage 33. The coil spring 34b is tensioned W8 in the axial direction so as to advance the valve body 34a to the fully open position.

Next, the operation of this embodiment will be explained.

First, at the start of air conditioning operation, the first i, l (not shown)
The air return means 31 is activated by the I controller, and as shown in FIG. 2, the air outlet 24 is fully closed by the air outlet louver 32, and the inlet end of the return air path 33 is fully opened by the on-off valve .

Therefore, the air sucked into the fan casing 26 by the operation of the indoor fan 30 is blown out from the air outlet 24 as indicated by the large arrow in the figure.
Most of the air passes through the return air passage 33 and returns to the upstream side of the air filter 28 .

To this end, the air in the fan casing 26 circulates around the air filter 28 and the indoor heat exchanger 29, repeatedly ventilating these 28,29.

Therefore, dust such as mold and dust that has entered or generated within the fan casing 26 is circulated together with the circulating air circulating within the fan casing 26, and the dust and mold are repeatedly captured by the air filter 28. Heat is exchanged repeatedly by the indoor heat exchanger 29.

As a result, the cleanliness of the circulating air is increased, the heat exchange efficiency is improved, and the temperature drop of the blown air during heating can be suppressed, thereby improving comfort.

Then, after a required period of time has elapsed since the start of the air conditioning operation, a first controller (not shown) turns the air blowing return means OFFIM* as shown in FIG. 3.

As a result, the air outlet 24 is fully opened by the rotating angle of the air outlet bar 32, while the coil spring 34b of the Itfl closing valve 34 expands. After being turned, the slider valve body 3
4a advances to the fully open position, and the inlet end of the return air passage 33 is fully closed.

For this reason, most of the air blown by the indoor fan 30 is blown out into the room etc. from the air outlet 24 which is fully open.

However, this blown air is purified because dust, mold, and other particles in the air are repeatedly captured by the air filter 28 when the air conditioning operation is started, and the amount of dust emitted into the room is reduced. can be reduced.

FIG. 4 and FIG. 5 are longitudinal sectional views showing a second embodiment of the present invention, in which the air blowing return means 31A is connected to a return air 1133 and an upper blowing louver whose inlet end is mainly opened and closed. 41, and a lower outlet louver 42 that mainly opens and closes the outlet 24.
A second air filter (not shown) controls the opening and closing of the pair of upper and lower blowout louvers 41 and 42 based on the temperature of the indoor heat exchanger 29. It is distinctive in that it has a , II control.

In other words, the second 1111 unit is set to II during heating operation, for example.
The air return means 31A is activated when the temperature of the indoor heat exchanger 29 falls below a set value due to a reduction in the negative load on the room or at the start of operation.

That is, the rotation angle of the upper blow-off louver 41 is controlled so as to open the inlet end of the return air passage 33 as shown in FIG.

On the other hand, when the temperature of the indoor heat exchanger 29 is higher than the set value, the operation of the air return means 31A is stopped by the second 1IllIIll device, and the inlet end of the return air path 33 is closed as shown in FIG. The upper blowout louver 41 is fully opened.
It is designed to control the rotation angle of.

Next, the operation of the second embodiment will be explained.

For example, when the heating load decreases due to an increase in indoor temperature, the capacity of an inverter-driven compressor (not shown) whose capacity is variable is reduced by an indoor controller (not shown).

For this reason, the temperature of the indoor heat exchanger 29 may drop below the set value.

Furthermore, even at the start of heating operation, the temperature of the indoor heat exchanger 29 may drop below the set value.

The second control is that the temperature of the indoor heat exchanger 29 has decreased! ! ! l! ! When detected by (not shown),
This second i! As shown in FIG. 4, the 1ltIl device controls the rotation angle of the upper blowout louver 41 so as to fully open the inlet end of the return air passage 33, and also controls the rotational angle of the lower blowout louver 42 so that its axis line Control it so that it stands almost vertically.

For this reason, the air from the indoor fan 30 is returned to the air passage 33 side and the air outlet 24 by a pair of upper and lower blow-off louvers 41 and 42.
It almost splits into two hands.

The air that has been diverted to the Suita outlet 24 is blown out into the room as it is as blown air.

On the other hand, a part of the air branched to the return air 'a33 side passes through the return air passage 33 to the air flow Ii on the upstream side of the air filter 28.
Returning to the circuit 27, the air filter 28 and the indoor heat exchanger 29 are ventilated again, the air is again blown by the indoor nozzle 30, and further, the air is branched again to the return air path 33, and the air is again passed through the air filter 28 and the indoor heat exchanger 29.
7 repeatedly.

Therefore, the air circulating in the ventilation passage 27 through the return air passage 33 is repeatedly ventilated through the air filter 28, so that the air filter 28 captures and purifies the dust, mold, etc. in the circulating air. Furthermore, by ventilating the indoor heat exchanger 29, the heat exchange efficiency here is increased, and even if the temperature of the indoor heat exchanger 29 decreases during heating operation, the temperature can be increased. I can do it.

Therefore, at the start of operation, the draft feeling of the blowing air can be suppressed to improve comfort, and the amount of dust released can be reduced.

After the operation of opening the inlet end of the return air passage 33 for the required time in this manner, the second tlllli! operation is performed as shown in FIG. ! (not shown), the rotation angle of the upper blowout louver 41 is set to L so that the inlet end of the return air passage 33 is fully opened.
12 '61; J.

As a result, most of the air from the indoor fan 30 is blown out from the air outlet 24 into the room.

Therefore, according to the second embodiment, even if the temperature of the indoor heat exchanger 29 decreases due to a reduction in the heating load, etc., the temperature drop of the air blown out from the outlet 24 is suppressed, suppressing the draft feeling, and providing comfortable comfort. can improve sex.

FIGS. 6 and 7 are longitudinal sectional views of a third embodiment of the present invention, and the air return means 31B of this embodiment is
The feature is that A is provided outside the indoor tIA 21.

That is, as shown in FIG. 6, the return air passage 33A is formed along the outer surface from the upper end in the figure of the outer end of the air outlet 24 to the lower outer surface of the front panel 22 having the suction port 23. Outside of drain pan 35A facing exit 24! The part is formed into an arc shape.

Further, a pair of upper and lower outlet louvers 51 and 52 are rotatably installed in the outlet 24, and the upper louver 51
When rotated in the horizontal direction, the inlet end of the return air passage 33A is opened.

Such an opening at the inlet end of the return air passage 33A is similar to the second controller of the second embodiment shown in FIG. When the second $IIWJ device detects this, the 12 controllers actuate the air blowing return means 31B and control the upper blowing louver 51 in the horizontal direction.

Therefore, due to reduction in heating load, etc., indoor heat exchanger 2
When the temperature of 9 falls below a required set value, the second 11360 device detects this and rotates the upper blowing louver 51 in the horizontal direction as shown in FIG.

For this reason, the air from the indoor fan 30 is divided into two hands by a pair of upper and lower blowout louvers 51 and 52, one side is returned to the Jira 33A side, and the other side is sent to the air outlet 24 (
1N, and the latter is directly blown into the room as blow-off air.

On the other hand, the air diverted to the return air 133A11 passes through the air path between the upper blow-off louver 51 and the outer bottom of the drain pan 35A, and is blown out of the indoor unit 21 from the upper end of the air outlet 24. reaches the inlet end of the inlet, further rises along the outer surface of the front panel 22, and returns to the outer surface of the suction port 23.

The blown air returned to the outside of the suction port 23 is returned to the suction port 2
3 into the ventilation passage 27 in the indoor unit 21.

This sucked air is again blown by the indoor fan 30, blown again to the outside return air passage 33A, and thereafter circulated through the aforementioned passage.

This I'il! As in the second embodiment, while the air is repeatedly passed through the air filter 28 and the indoor heat exchanger 29, dust, mold, and other particles in the air are captured and purified by the air filter 28. It is reheated by the indoor heat exchanger 29 to raise the temperature.

In this way, after waiting for the required time to open the inlet end of the return air passage 33A, the operation of the air return means 31B is stopped, and the upper blowing louver 51 is erected vertically as shown in FIG. It is controlled by the second control Wa as follows.

This allows indoor)? The air blown from the air outlet 30 is guided by a pair of upper and lower air outlet louvers 51 and 52, and most of the air flows through the air outlet 2.
4 and is blown into the room.

Therefore, in this third embodiment as well, similarly to the second embodiment, the temperature drop of the blown air is suppressed and the draft feeling is suppressed.
1, and can improve comfort.

FIG. 8 is a longitudinal sectional view showing a fourth embodiment of the present invention,
In this embodiment, the 11-sided shape of the drain pan 35B is formed into a substantially circular arc shape, and, for example, a pair of left and right return pipes 60a are provided at the inlet end of the return air passage 33B.

60b is provided, and the angle of rotation of the pair of upper and lower blow-off louvers 41, 42 is controlled by a second controller (not shown) similar to the second embodiment. There is.

That is, in this embodiment, by forming the drain pan 35B in an arc shape, the air blown from the indoor fan 30 is smoothly returned to the air passage 33B, and the pair of left and right return distribution channels W60
a, Bob guides the return air to the air filter 28 and the upper part of the indoor heat exchanger 129.

This embodiment can also provide the same effects as those of the embodiments described above.

Note that the present invention is not limited to the above-mentioned embodiments, and for example, the air filter 28 may be configured with an electrostatic filter to improve dust collection efficiency.

〔Effect of the invention〕

As explained above, the present invention provides a means for returning a small amount of the air from the blower fan to the suction port, so that the returned air is repeatedly passed through the air filter and the indoor heat exchanger. By increasing the efficiency of capturing dust in the return air, the cleanliness level can be improved.
By increasing the heat exchange efficiency in the indoor heat exchanger, it is possible to suppress the draft feeling caused by the temperature drop of the blown air, thereby improving comfort.

Therefore, according to the present invention, it is possible to increase the cleanliness of the air blown into the room from the indoor fan and to improve comfort.

[Brief explanation of drawings]

Figure 1 shows the first example of the case where the present invention is applied to a wall-mounted indoor unit.
FIG. 2 and FIG. 3 are enlarged views of the main parts of FIG. FIG. 7 is a vertical cross-sectional view of a third actual flow example of the present invention, FIG. 8 is a vertical cross-sectional view of a fourth embodiment of the present invention, and FIG. 9 is a vertical cross-sectional view of an indoor unit in a conventional air conditioner. 10 is a graph showing the dust emission m of the conventional example shown in FIG. 9 corresponding to the air conditioning operation ",). 21...Indoor unit, 23...Suction port, 24...・Air outlet, 27... Ventilation duct, 28... Air filter, 29
...Indoor heat exchanger, 30...Indoor fan, 31.
31A. 31B, 31C...Blower return means, 32...Blowout louver, 41.51...Upper blowout louver, 42.52.
... Lower blowout louver, 33.33A, 33B ... Return air path, 34 ... Opening/closing valve, 34a ... Slider valve, 3
4b...Coil spring, 60a, 60b...Return piping.

Claims (1)

[Claims] 1. A ventilation path that communicates an inlet that sucks in air from an air-conditioned space with an outlet that blows out temperature-controlled air, an air filter interposed in the middle of this ventilation path, and an indoor heat exchanger. and an indoor fan, characterized in that an air conditioner is provided that returns at least a portion of the air from the indoor fan to the suction port. 2. Activate the air return means at the start of air conditioning operation,
The air conditioner according to claim 1, further comprising a first control means for returning at least part of the air blown from the indoor fan to the suction port. 3. A second device that detects the temperature of the indoor heat exchanger, and when the detected temperature is below a set value, operates the air return means to return at least a portion of the air from the air blower fan to the suction port side.
The air conditioner according to claim 1, further comprising a control means.