JPH04358511A - Filter clogging determining device - Google Patents

Abstract

PURPOSE:To determine correctly the clogging state of a filter. CONSTITUTION:Magnetic flux variation generated by the rotation of a permanent magnet 3 mounted on a rotating shaft 1a of an AC fan motor 2 is sensed by a Hall IC4, and a sensing signal for the rotation of the AC fan motor 2 is output. The phase angle to the AC fan motor 2 when a power source is on is controlled by a phase control unit 6 in a manner that the number of rotations of the AC fan motor 2 based on the sensing signal from the hole IC4 conforms with the target number of rotations. The value of difference between the operation phase angle and the standard phase angle when the operation number of rotations is controlled to the target number of rotations by the phase control unit 6 is computed by a microcomputer 5 as the load variation amount of a cross flow fan 1, and the clogging state of a filter is distinguished correctly based on the load variation amoung of the cross flow fan 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter clogging determination device that can accurately determine whether a filter in an indoor unit of an air conditioner is clogged.

0002

[Prior Art] Conventionally, when issuing a filter cleaning sign in an indoor unit of an air conditioner, the time when the filter needs to be cleaned (filter cleaning time) is determined based on the cumulative operating time of the air conditioner. There is.

0003

However, when the time to clean the filter is determined based on the cumulative operating time of the air conditioner as described above, the following problems arise. In other words, if the indoor unit of the air conditioner is installed in a place with little dirt and dust, even if the cumulative operating time mentioned above reaches the filter cleaning time, the filter is not actually clogged and the filter cannot be cleaned. The problem is that signs are of no use.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a filter clogging determination device that can accurately determine the clogging state of a filter in an indoor unit of an air conditioner.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the filter clogging determination device of the invention according to claim 1 detects the rotation of the fan 1 and indicates the rotation. Rotation detection means 3 and 4 output detection signals, and the operating rotation speed of the fan 1 is detected based on the detection signals from the rotation detection means 3 and 4, and the detected operating rotation speed of the fan 1 and The value of the difference from the standard rotation speed is calculated, and if the calculated difference value is greater than a predetermined value, it is determined that the filter that filters the air supplied to the fan 1 is clogged. The present invention is characterized in that it includes filter clogging determination means.

Further, the filter clogging determination device of the invention according to claim 2 includes rotation detecting means 3, 4 for detecting the rotation of the fan 1 and outputting a detection signal representing the rotation, and the rotation detecting means 3, 4. The operating speed of the fan 1 is detected based on the detection signal from the fan 1, and the phase angle of the fan motor 2 that drives the fan 1 when the power is turned on is controlled so that the operating speed becomes the target rotation speed. The fan 1 rotates at the target rotation speed under the control of the fan motor control means 5 and 6, the phase detection means that detects the phase angle when the power to the fan motor 2 is turned on, and the fan motor control means 5 and 6. calculate the difference between the phase angle of the fan motor 2 detected by the phase detection means when the power is turned on and the standard phase angle when The present invention is characterized in that it includes filter clogging determining means for determining that the filter for filtering the air supplied to the fan 1 is clogged.

[0007]

[Operation] In the invention according to claim 1, the rotation detection means 3, 4
The rotation of the fan 1 is detected and a detection signal representing the rotation is output. Then, the filter clogging determining means detects the operating rotation speed of the fan 1 based on the detection signals from the rotation detection means 3 and 4, and the detected operating rotation speed of the fan 1 is compared with the standard rotation speed. The difference value is calculated. If the calculated difference value is greater than or equal to a predetermined value, it is determined that the filter that filters the air supplied to the fan 1 is clogged. In this way, by determining the amount of change in load based on the amount of change in rotational speed of the fan 1 as the degree of clogging of the filter, the state of clogging of the filter can be correctly determined.

Further, in the invention according to claim 2, the rotation of the fan 1 is detected by the rotation detecting means 3 and 4, and a detection signal representing the rotation is output. Then, the fan motor control means 5 and 6 detect the operating rotation speed of the fan 1 based on the detection signals from the rotation detection means 3 and 4, and turn on the power to the fan motor 2 that drives the fan 1. The phase angle of the fan 1 is controlled based on the detected operating rotation speed, and the fan 1 is rotated at the target rotation speed. Then, the filter clogging determining means calculates the value of the difference between the phase angle of the fan motor 2 when the power is turned on and the standard phase angle. If the calculated difference value is greater than or equal to a predetermined value, the fan 1
It is determined that the filter that filters the air supplied to the system is clogged. In this way, the fan motor 2
Fan 1 based on the amount of phase angle change when the power is turned on
By using the load change amount as the degree of filter clogging, the clogged state of the filter can be accurately determined.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to illustrated embodiments. FIG. 1 shows a rotation speed control system of a fan motor that drives a crossflow fan 1 in an indoor unit of an air conditioner. A permanent magnet 3 is attached to a rotating shaft 2a of an AC (alternating current) fan motor 2. Changes in magnetic flux caused by the rotation of the permanent magnet 3 are detected by a Hall IC (integrated circuit) 4, and a detection signal representing the rotation of the AC fan motor 2 (that is, the rotation of the crossflow fan 1) is output. The microcomputer (hereinafter simply referred to as microcomputer) 5 receives the detection signal from the Hall IC 4 and determines the operating rotation speed of the AC fan motor 2 based on the detection signal and the target rotation speed preset according to the fan tap. Calculate the deviation. Then, based on the calculated deviation value, the amount of change in the phase angle when the AC power supply is turned on for the AC fan motor 2, which is necessary when correcting the operating rotation speed to the target rotation speed, is calculated. A phase signal representing the amount of change in the phase angle is output to the phase control unit 6.

The phase control unit 6 controls the phase angle of the AC fan motor 2 when the power is turned on based on a phase signal inputted from the microcomputer 5. In this way, A
Feedback control is performed so that the operating rotation speed of the C fan motor 2 becomes the target rotation speed. Further, the microcomputer 5 determines the load on the crossflow fan 1 based on the phase angle and the standard phase angle at the time of power-on when the operating rotation speed of the AC fan motor 2 is feedback-controlled as described above. A change in characteristics is detected, and the target rotation speed is corrected in accordance with the changed load characteristics.

In the rotation speed control system of the AC fan motor 2 having the above configuration, if the filter that filters the air supplied to the cross flow fan 1 becomes clogged, the load characteristics of the cross flow fan 1 change. . Then, since the operating rotation speed of the AC fan motor 2 is feedback-controlled as described above, the phase angle when the power is turned on is controlled as the load of the cross flow fan 1 changes, and the AC fan motor 2 The operating rotation speed is changed so that it becomes the target rotation speed. As a result, the phase angle of the AC fan motor 2 when the power is turned on deviates from the standard phase angle. Therefore, in this embodiment, the degree of load change of the crossflow fan 1, that is, the degree of filter clogging, is determined based on the degree of deviation of the phase angle from the standard phase angle when the power is turned on.

That is, the permanent magnet 3 and the Hall IC 4
The rotation detecting means is constituted by: Further, the microcomputer 5 constitutes the phase detection means and the filter clogging determination means, and the microcomputer 5 and the phase control unit 6
This constitutes the fan motor control means.

FIG. 2 is a flowchart of the filter clogging determination processing operation executed by the microcomputer 5. As shown in FIG. The filter clogging determination processing operation will be described below with reference to FIG. In step S1, the AC fan motor 2 that drives the crossflow fan 1 is operated. In step S2, the flap is fixed at a fully open position in order to keep the static pressure caused by the flap that controls the blowing direction at the air outlet of the indoor unit at a constant pressure and eliminate the influence of the static pressure caused by the flap. In step S3, the fan tap is set to the tap specified by the user, and feedback control is started so that the operating rotation speed of the AC fan motor 2 becomes the target rotation speed of the fan tap specified by the user.

[0014] In step S4, it is determined whether a predetermined time has elapsed since the fan tap was set in step S3. As a result, if the predetermined time has elapsed, the process advances to step S5. On the other hand, if not, wait until the predetermined time has elapsed. In this way, after the Fanta tap is set, the predetermined time (for example, 3
5 seconds), the above-mentioned rotational speed feedback control of the AC fan motor 2 is completed, and it is determined that the crossflow fan 1 is rotating at the target rotational speed at the set fanta tap. be. In this way, after it is confirmed that the number of rotations of the cross flow fan 1 has reached the target number of rotations, a clogging determination operation is started.

In step S5, it is determined whether the amount of filter clogging is greater than or equal to a predetermined amount. If the result is the predetermined amount or more, proceed to step S6; otherwise, step S
Proceed to step 7. Here, the amount of clogging of the filter is calculated as follows. That is, when the filter becomes clogged, the load on the cross flow fan 1 changes and the operating speed tends to deviate from the target rotation speed. Then, as described above, feedback control is performed so that the operating rotation speed of the AC fan motor 2 becomes the target rotation speed. As a result, as shown in FIG. 3, the power to the AC fan motor 2 is turned on depending on the degree of deviation of the operating speed of the cross flow fan 1 from the target speed (that is, the degree of clogging of the filter). The phase angle at the time (hereinafter simply referred to as the operating phase angle τ1) deviates from the standard phase angle τ0 in the fanta tap set in step S3. Therefore, the value of the difference between the operating phase angle τ1 and the standard phase angle τ0 is calculated, and if this calculation result is greater than or equal to the first predetermined value, the amount of clogging is greater than the predetermined amount and the filter needs to be cleaned. It is to judge.

In step S6, since the amount of clogging of the filter is greater than a predetermined amount, a "filter cleaning" message is displayed to prompt the user to clean the filter. In step S7, the reduction in performance of the crossflow fan 1 due to filter clogging is corrected. This correction of the capacity change of the cross flow fan 1 is carried out as follows. That is, when the value of the difference between the operating phase angle τ1 and the standard phase angle τ0 exceeds a second predetermined value different from the first predetermined value, the current target rotation of the AC fan motor 2 In terms of numbers, the target rotation speed of the AC fan motor 2 is corrected to be higher by a predetermined rotation speed, assuming that the capacity of the cross flow fan 1 is reduced. As a result, the rotation speed of the crossflow fan 1 increases more than the target rotation speed of the fanta tap set in step S3 above, and the intake amount of indoor air, which has been reduced due to clogging, increases, and the capacity decreases due to filter clogging. is corrected.

In step S8, the flap that was fully opened in step S2 is set or swung at a predetermined angle in accordance with information previously stored in a memory or the like, and the filter clogging determination processing operation is completed.

As described above, in this embodiment, the operating phase angle τ1 of the AC fan motor 2 that drives the cross-flow fan 1 in the indoor unit is controlled by the microcomputer 5 and the phase control unit 6. Feedback control is performed so that the operating rotation speed of the fan tap becomes the target rotation speed (or corrected target rotation speed) set by the user. After that, the microcomputer 5 calculates the deviation of the operating phase angle τ1 from the standard phase angle τ0, and if the calculation result is equal to or greater than the first predetermined value, the amount of clogging of the filter is equal to or greater than the predetermined amount. The message “Clean the filter” is displayed. Therefore, the amount of clogging of the filter can be determined based on the value corresponding to the amount of change in the load of the cross-flow fan 1, and the state of clogging of the filter can be correctly determined.

The filter clogging determination processing operation according to the present invention is not limited to the flowchart of the above embodiment. Furthermore, the correction of the change in the capacity of the crossflow fan 1 carried out in step S7 in the clogging determination processing operation is not necessarily a necessary process for carrying out the present invention, and may be omitted. In the above embodiment, after the operating rotation speed of the AC fan motor 2 is feedback-controlled to the target rotation speed, the degree of deviation between the operating phase angle τ1 and the standard phase angle τ0 is calculated to detect the clogging state. I'm trying to determine. However, the invention is not limited thereto. That is, contrary to the above embodiment, when the operating phase angle τ1 of the AC fan motor 2 is the standard phase angle τ0 (that is, when the operating rotation speed of the AC fan motor 2 is not under feedback control), the AC fan motor There is no problem in determining the clogging state by calculating the value of the difference between the operating rotation speed of No. 2 and the target rotation speed. In that case, the rotation speed control system for the AC fan motor 2 as described above is not necessarily required.

[0020]

As is clear from the above description, the filter clogging determining device of the invention according to claim 1 uses the filter clogging determining means to detect the operating rotation of the fan detected by the detection signal from the rotation detecting means. The difference between the number of rotations and the standard rotation speed is calculated, and if the calculated difference is greater than a predetermined value, it is determined that the filter is clogged. Filter clogging can be determined based on the amount of load change. Therefore, the clogged state of the filter in the indoor unit of the air conditioner can be correctly determined.

Further, in the filter clogging determination device of the invention according to claim 2, when the fan is rotating at a target rotation speed under the control of the fan motor control means, the filter clogging determination means determines whether the fan motor is Calculate the difference between the phase angle when the power is turned on and the standard phase angle,
If the calculated difference value is greater than or equal to a predetermined value, it is determined that the filter is clogged, so that it is possible to determine whether the filter is clogged according to the amount of change in the fan load. Therefore, the clogged state of the filter in the indoor unit of the air conditioner can be correctly determined.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a filter clogging determination device of the present invention.

FIG. 2 is a flowchart of filter clogging determination processing operation.

FIG. 3 is a diagram showing the relationship between the operating phase angle τ1 and the standard phase angle τ0.

[Explanation of symbols]

1...Cross flow fan, 2
...AC fan motor, 3...permanent magnet, 4...Hall IC,
5...Microcomputer,
6...Phase control unit.

Claims (2)

[Claims] 1. Rotation detection means (3, 4) for detecting the rotation of the fan (1) and outputting a detection signal representing the rotation; The operating rotation speed of the fan (1) is detected, the difference between the detected operating rotation speed of the fan (1) and the standard rotation speed is calculated, and the value of the calculated difference is greater than or equal to a predetermined value. A filter clogging determining device characterized in that it is provided with filter clogging determining means for determining that a filter for filtering air supplied to the fan (1) is clogged if the above-mentioned fan (1) is filtered. 2. Rotation detecting means (3, 4) for detecting the rotation of the fan (1) and outputting a detection signal representing the rotation; A fan that detects the operating rotation speed of the fan (1) and controls the phase angle of the fan motor (2) that drives the fan (1) when the power is turned on so that the operating rotation speed becomes the target rotation speed. motor control means (5, 6); phase detection means for detecting the phase angle of the fan motor (2) when the power is turned on; and the fan motor control means (
The phase angle and standard phase angle when the power is turned on for the fan motor (2) detected by the phase detection means when the fan (1) is rotating at the target rotation speed under the control of 5 and 6). If the calculated difference value is greater than or equal to a predetermined value, the fan (
1) A filter clogging determining device characterized by comprising filter clogging determining means for determining that a filter that filters air supplied to the air filter is clogged.