JPH02306048A - Air conditioner - Google Patents

Abstract

PURPOSE:To eliminate or reduce the noise and vibration of fan by providing a control means which outputs the signal to an actuating means to move movable vanes which are disposed in the air intake grill to eliminate the rotational speed fluctuation. CONSTITUTION:The rotational speed of the fan motor 19 is detected by a rotational speed sensor 20, and the rotational speed is automatically controlled by a CPU. A determination is made over a time interval t1 as to Whether the fan experienced enough resonant vibration to cause the load acting on it to change, resulting in the fan speed change, with the grill set in its initial angle. Further, a determination is made over another time interval t2 as to whether there actually is a rotational speed change. If there is, the angle is modulated. When the rotational speed change is no longer present, the CPU checks for the difference between the outputs from temperature sensors 9, 10 attached to the heat exchanger 2. If the temperature difference between the respective refrigerant lines is found to be greater than a predetermined value, either the movable vanes 7 in the upper grill 5 or the movable vanes 8 in the lower grill 6 are adjusted their angle. After a certain elapsed time t3, the afore- described processes are repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an air conditioner that suppresses noise and vibration generated by a fan of an indoor unit.

<Conventional technology> Conventional air conditioners have a suction grill at the upper front of the casing of the indoor unit, an air outlet at the upper front of the casing, and a rectangular parallelepiped heat exchanger and cylindrical cross flow inside the casing. Maybe if you have a fan installed. The heat exchanger is installed obliquely with the upper part facing the rear surface of the casing and the lower part facing the casing rear surface, while the cross-flow fan is installed horizontally along the lower part of the heat exchanger. By operating this cross-flow fan, indoor air is sucked into the case through the intake grill at the top of the front, passes through the heat exchanger and cross-flow fan, and is blown into the room from the air outlet at the bottom of the front. There is.

Further, the fan is automatically controlled to a predetermined rotation speed depending on the set operating mode.

<Problems to be Solved by the Invention> By the way, when the above-mentioned conventional air conditioners are used continuously, dust in the air accumulates in the heat exchanger, or frost occurs temporarily due to ambient temperature conditions. Therefore, in the air flow path inside the casing, the pressure difference between the suction side and the blowout side of the crossflow fan may change.

Additionally, when the operating mode is changed and the rotation speed setting is changed, the distance between the upper and lower distribution channels is different, resulting in uneven wind speed or volume within this distribution channel. , the pressure applied to the suction side surface of the outer periphery of the fan may become uneven. For this reason, the fan may cause resonance vibration due to the unbalance of the pressure it receives, and there is a problem in that this vibration generates noise. Furthermore, due to the above-mentioned non-uniform wind speed or air volume, a temperature difference occurs between the upper and lower parts of the heat exchanger, and the refrigerant is concentrated in a part of the heat exchanger, resulting in a reduction in heat exchange capacity. There is a problem with the decrease in In particular, when a heat exchanger having a plurality of refrigerant paths is provided, there is a problem in that the refrigerant remains in some of the paths (unbalanced flow), resulting in a noticeable decrease in performance.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an air conditioner that can eliminate and suppress fan vibration and noise and maintain a high level of heat exchange performance.

Means for Solving the Problems> In order to achieve the above object, the present invention provides an air conditioner having a heat exchanger, a fan, and a motor inside a casing having a suction grill, in which the suction grill has a plurality of It is characterized by the provision of movable blades.

Further, a rotation speed detection sensor that detects the rotation speed of the fan, a rotation fluctuation detection means that receives a signal representing the rotation speed from the rotation speed detection sensor and detects rotation fluctuation, and a drive means that drives the movable blade. and control means for outputting a signal to the driving means to drive the movable blade so as to eliminate the rotational fluctuation based on a signal output by the rotational fluctuation detection means indicating that rotational fluctuation has occurred. is desirable.

Furthermore, a plurality of temperature detection sensors provided in the heat exchanger, a driving means for driving the movable blade, and an output of each temperature detection sensor are received to uniformly distribute the heat load on each part of the heat exchanger. It is desirable to include a control means for outputting a signal to the drive means for driving the movable blade so as to drive the movable blade.

Effect> When resonance vibration occurs, by adjusting the angle of the plurality of movable blades provided on the suction grill, the pressure distribution on the suction side of the fan changes, and the vibration of the fan deviates from the resonance point. Therefore, resonance vibration is eliminated and no noise is generated. Furthermore, by adjusting some of the movable blades, the wind speed and volume can be made uniform within the air circulation path. Therefore, the pressure on the suction side of the fan becomes uniform, and resonance vibration of the fan becomes less likely to occur.

Furthermore, when the above-mentioned resonance vibration occurs, the load on the fan fluctuates and the rotational speed fluctuates (rotational fluctuation or rotational speed surge). Therefore, the rotational fluctuation is detected by the rotational fluctuation detection means, and the movable blade is controlled by the control means via the driving means so as to eliminate this rotational fluctuation.
Resonant vibration and noise are quickly eliminated.

Furthermore, multiple temperature sensors installed in the heat exchanger detect the temperature of each part of the heat exchanger so that there are no temperature differences, that is, the air volume is uniform.

When the plurality of movable blades are divided and controlled, the refrigerant is not concentratedly condensed in a part of the heat exchanger, and the capacity of the heat exchanger is not reduced.

In particular, when a heat exchanger having a plurality of refrigerant paths is provided, the flow through each path becomes smooth and the heat exchange capacity is maintained at a high level.

<Example> Hereinafter, the air conditioner of the present invention will be explained in detail with reference to the illustrated example.

As shown in FIG. 1, this air conditioner is equipped with a suction grill 4 at the upper front of a casing 1 of an indoor unit, an air outlet 11 at the lower front, and a rectangular parallelepiped heat exchanger 2 inside the casing 1. A cylindrical cross flow fan 3 is provided. The heat exchanger 2 is installed diagonally with the upper part 2a facing the rear side of the casing l and the lower part 2b facing the front side of the casing l, while the cross flow fan 3 is installed horizontally along the lower part of the heat exchanger 2. There is. As schematically shown in FIG. 4, the heat exchanger 2 has refrigerant paths in an upper portion 2a and a lower portion 2b, and these paths are parallel to each other. And this upper part 2a and lower part 2b
A temperature sensor of 9°lO is attached to each. A fan motor 19 and a rotation speed sensor 20 for detecting the rotation speed of the fan 3 are attached to the cross flow fan 3.

The rotation speed sensor 20 is configured by a Hall IC (integrated circuit) and is configured to detect changes in the magnetic field according to the rotation generated by a magnet attached to the rotating shaft of the fan 3. The suction grill 4 is composed of an upper grill 5 having four movable blades 7 shaped like shutters, and a lower grill 6 similarly having four movable blades 8. The upper grill 5 is
As shown in FIGS. 2 and 3, on the side, there is a blade drive motor 21 as a driving means that rotates in a stepwise manner in response to a pulse input signal, a rack 30, and a blade protruding from the end 7a of each movable blade 7. It includes a pinion 31 attached to the tip of a shaft 40. Each shaft 40 is rotatably supported by a frame 41. The toothed side 30a of the rack 30 meshes with each pinion 3I, and the flat side 30b is supported by four rollers 32. When the blade drive motor 2N rotates in either direction, the rack 30 moves in the vertical direction via the bevel gears 33 and 34, the pinion 31 rotates, and the movable blade 7 rotates together with the shaft 40, causing the angle I'm trying to change that.

On the other hand, the lower grille 6 has movable blades 8 that can be opened and closed in exactly the same way as the upper grille 5 described above. Moreover, as shown in FIG.
It includes U15, memory 16, driver 17, and I8.

This CPU 15 is connected to the fan 3 from the rotation speed sensor 20.
receives a signal indicating the rotation speed of the fan motor I9, processes this signal according to a predetermined procedure stored in the memory 16, outputs a control signal to the driver 17 so that the fan 3 reaches a predetermined rotation speed, and controls the fan motor I9. A control signal for changing the angle of movable blades 7 and 8 is output to driver 18 when rotational fluctuation occurs due to load fluctuation. Also, this CPU
15 is the temperature sensor 9. From IO to the upper part 2a of the heat exchanger 2.

Upon receiving a signal indicating the temperature of the lower portion 2b, this signal is processed according to a predetermined procedure stored in the memory 16, and a control signal for changing the angle of one of the movable blades 7 or 8 is output to the driver 18. Based on the received control signals, the drivers 17j18 respectively drive the fan motors 19. The blade drive motors 21 and 26 are driven. Note that the blade drive motor 26
is provided on the lower grille 6 and has the same function as the blade drive motor 21 described above.

This air conditioner operates as follows.

■As shown in Figure 6(a), when the operation starts, it is first determined whether the operation is cooling or heating (step S,
), in heating mode, the heating intensity is high (H).

Determine whether the setting is medium (M) or 1-low (L) (step S), and determine the degree of dryness of the air.
As shown in FIG. 7, the initial angle of the movable blade 7.8 is set (step SS). On the other hand, in the case of cooling operation as well, the strength of the cooling is strong (H) and medium (M).

The initial angles of the movable blades 7 and 8 are set by determining whether the setting is low (L) (step S□) and determining the degree of humidity of the air (step S, 3). Then, the fan motor 19 is controlled by the rotation speed sensor 20.
The rotation speed is detected (step S), and the rotation speed is automatically controlled by the CPU 15 in accordance with the setting of H, M, or L.

■Next, as shown in Fig. 6(b), at the set initial angle, it is determined whether the fan resonates and vibrates, the load fluctuates, and the rotation fluctuates (rotation speed surge). ,). This determination is performed over a predetermined time t1 (step 5ll). If it is determined that rotational fluctuation has occurred, the angles of the movable blades 7 and 8 are changed after the time t1 has elapsed (step S7). Furthermore, a predetermined time t is spent to determine whether or not a rotational fluctuation has occurred (step S8+S), and if so, the process returns to step S7 and the angle is changed again. Then, steps S7 to S are repeated until the vibration of the fan 3 due to the unbalanced pressure distribution deviates from the resonance point.

■In this way, when there is no rotational fluctuation, or when it is determined that there is no rotational fluctuation at the initial angle set in (■) above (step S5), the CPU 15 activates the temperature sensor 9 attached to the heat exchanger 2. A difference in output of 10° is detected (Step S, .), and it is determined whether the temperature difference between the upper part 2a and the lower part 2b, that is, each refrigerant path, is larger than a predetermined value (Step S, υ. The temperature difference is large. If it is judged that The grill is left open.Then, wait for the predetermined time t3 to elapse (step 513), and then repeat the above steps S.
. The series of processes from S to S+3 are repeated. Then, when it is determined that the temperature difference is smaller than a predetermined value (step S
, ), Returning to step S4 of (■) above, during driving, always
The processing from S4 to S13 is performed.

In this way, by automatically adjusting the angle of the movable blades 7.8, vibrations and noise of the fan 3 can be quickly eliminated. In addition, by adjusting the angles of the movable blades 7 and 8 independently of each other, vibrations of the fan 3 can be further suppressed, and the flow of refrigerant in the upper part 2a and lower part 2b of the heat exchanger 2 is smoothed. heat exchange capacity can be maintained at a high level.

Note that, of course, the suction grill 4 may be further divided into a large number of parts and each part may be controlled with high precision.
The heat exchanger 2 may be further provided with a large number of refrigerant paths and temperature sensors for control.

<Effects of the Invention> As is clear from the above, the air conditioner of the present invention has the following effects:
Since multiple movable blades are provided on the suction grill of the indoor unit casing, fan vibration and noise can be eliminated and suppressed.

The invention also includes a rotation speed detection sensor that detects the rotation speed of the fan, a rotation fluctuation detection means that receives a signal representing the rotation speed from the rotation speed detection sensor and detects rotation fluctuation, and a drive means that drives the movable blade. , when equipped with a control means for controlling the movable blade via a driving means so as to eliminate the rotational fluctuation based on a signal indicating that rotational fluctuation has occurred outputted by the rotational fluctuation detection means, the automatic It is possible to quickly eliminate and suppress resonance vibration.

Furthermore, a plurality of temperature detection sensors provided in the heat exchanger, a drive means for driving the movable blades, and receiving outputs from each of the temperature detection sensors, uniformize the heat load on each part of the heat exchanger. When the movable vane is provided with a control means that outputs a signal to control the movable blade via the drive means, the heat exchange capacity can be maintained at a high level. In particular, when a heat exchanger having a plurality of refrigerant paths is provided, drifting between the refrigerant paths can be effectively suppressed.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an air conditioner according to an embodiment of the present invention, FIGS. 2 and 3 are views showing the upper grill of the air conditioner, and FIG. 4 is a heat exchanger of the air conditioner. FIG. 5 is a block diagram showing a control system for the fan and movable blades of the air conditioner; FIG. 6 is a flow chart showing the operation of the air conditioner;
FIG. 7 is a sectional view showing the state of the air conditioner during operation. l... Indoor unit casing, 2... Heat exchanger, 3...
...Cross flow fan, 4...Suction grill, 7.8
．． 12...Movable blade, 9,10...Temperature sensor, 1
1... Suction port, 15... CPU, 16... Memory, 19... Fan motor. Patent applicant: Daikin Industries, Ltd., agent Patent attorney Aohaku Ao and one other person Figure 1 Figure 7 Figure 6 (a)

Claims (3)

[Claims] (1) Inside the casing (1) with a suction grill (4), a heat exchanger (2), a fan (3) and a motor (19)
An air conditioner comprising: an air conditioner, characterized in that the suction grille (4) is provided with a plurality of movable blades (7, 8). (2) a rotational speed detection sensor (20) that detects the rotational speed of the fan (3); and a rotational fluctuation detection means that detects rotational fluctuation upon receiving a signal representing the rotational speed from the rotational speed detection sensor (20). and driving means (21, 2) for driving the movable blades (7, 8).
and (6) a control means for outputting a signal to the driving means to drive the movable blade so that the rotational fluctuation is eliminated, based on a signal indicating that a rotational fluctuation has occurred, which is output by the rotational fluctuation detection means. 15) The air conditioner according to claim 1, further comprising: 15). (3) A plurality of temperature detection sensors (9, 10) provided in the heat exchanger, and driving means (21, 2) for driving the movable blades (7, 8).
6), and the movable blades (7, 10) receive the outputs of the temperature detection sensors (9, 10) to equalize the heat load on each part (2a, 2b) of the heat exchanger (2). control means (1) for outputting a signal for driving 8) to the driving means (21, 26);
5) The air conditioner according to claim 1, further comprising: 5).