JPH033999A - Air conditioner - Google Patents

Abstract

PURPOSE:To timely detect an abnormality and improve reliability by outputting an abnormality signal when the difference between the rotating speed of a fan motor and the abnormality judgment rotating speed from an abnormality judgment switching means is the preset value or above continuously for a preset period. CONSTITUTION:A fan control means 2 controlling the rotating speed of a fan motor 3 based on the difference between the preset rotating speed of the fan motor 3 corresponding to the air quantity set by an air quantity switching means 1 and the rotating speed of the fan motor 3 detected by a rotating speed detecting means 6 and an abnormality judgment switching means 4 reading the air quantity mode set by the air quantity switching means 1 and outputting the abnormality judgment rotating speed for each air quantity mode judging the abnormal state of the fan motor 3 as the judgment signal air provided. An abnormality detecting means 5 calculating the difference between the rotating speed of the fan motor 3 under operation obtained by reading the detected signal from the rotating speed detecting means 6 and the abnormality judgment rotating speed obtained by reading the judgment signal from the abnormality judgment switching means 2 and outputting an abnormality signal to the fan control means 2 when the difference is the preset value or above continuously for a preset period is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an air conditioner with an improved detection method for detecting abnormal rotation of a blower motor.

(Prior art) Conventionally, an induction motor is used for the blower motor of an air conditioner, and the current waveform from an AC power source is controlled by a triac within a current width of 0° to 180° to control the rotation speed of the motor. Some motors use phase control to increase the width of the current waveform in stages to reach a set rotational speed.

When the motor breaks down, the rotation speed does not reach the set rotation speed and the rotation speed decreases, resulting in an abnormal condition, which continues.
If the blower motor does not rotate and locks, the width of the current waveform to the blower motor increases in an attempt to reach the set rotation speed, which causes an excessive load on the windings of the blower motor and an abnormal temperature rise, causing surrounding parts to heat up. This may cause deformation or failure.

Therefore, in order to protect the surrounding parts due to the abnormal state of the blower motor, the rotation speed of the blower motor is detected as shown in Figure 4, and the rotation speed is decreased from a predetermined value A, which is less than the minimum set rotation speed. There is a control method that sometimes determines that there is an abnormality and stops the air conditioner.

However, in such a method, the abnormal state is set to be below a certain predetermined value A, so even if there are multiple rotation speed settings, the predetermined value A must be set lower than the minimum rotation speed. For example, In Figure 4, when operating with the setting set to strong wind, in an abnormal state where the blower motor is running at a rotation speed between strong wind and light wind even though the AC current is fully energized, the various low values A Since it is not below, it is not detected as an abnormal state.

Therefore, continuation of such an abnormal state above the minimum rotational speed may lead to an abnormal temperature rise, and conventional control methods have problems.

(Problem to be Solved by the Invention) As described above, with the conventional method for detecting an abnormality in the blower motor in an air conditioner, it was possible to detect an abnormality at a speed lower than the minimum rotation speed of the blower motor setting. Since it is not possible to detect each abnormality in the rotation speed, abnormality detection may be delayed or impossible, and abnormal temperature rises in the blower motor may lead to deformation and temperature breakdown of surrounding parts.

The present invention has been made in consideration of the above circumstances, and it is an object of the present invention to provide an air conditioner that is unreliable and capable of detecting an abnormality at each set rotation speed of the blower motor.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes an air volume switching means that sets the air volume, a blower motor that rotates the blower, and a blower motor that detects the number of rotations of the blower motor and generates a detection signal. The rotation speed of the blower motor is controlled based on the difference between the output rotation speed detection means, the set rotation speed of the blower motor corresponding to the air volume set by the air volume switching means, and the rotation speed of the blower motor detected by the rotation speed detection means. An air conditioner having an abnormality determination switching means that sets an abnormality determination rotation speed based on the air volume set in the air volume switching means, and a rotation speed of the blower motor detected by the rotation speed detection means. and the abnormality determination rotation speed from the abnormality determination switching means, and if the difference is greater than or equal to a predetermined value, a predetermined period of $
The structure includes an abnormality detection means that outputs an abnormality signal when one pillow is applied.

(Function) According to such a configuration, the rotation speed of the blower motor is detected, the difference between the detected rotation speed and the set rotation speed is compared, and if the difference exceeds a predetermined value, the rotation speed is detected. When a predetermined period of time has elapsed in this state, it is determined that the blower motor is in an abnormal state and protection control is performed, so that protection control of the blower can be performed according to each rotation speed.

(Embodiment) Fig. 1 is a control block diagram of a blower motor of an air conditioner according to an embodiment of the present invention. A blower motor 3 that rotates the blower motor 3, a rotation speed detection means 6 that detects the rotation speed of the blower motor 3 and outputs a detection signal, and a set rotation speed of the blower motor 3 corresponding to the air volume set by the air volume switching means 1. Based on the difference in the rotation speed of the blower motor 3 detected by the rotation speed detection means 6, the air volume mode set in the air blower control means 2 that controls the rotation speed of the blower motor 3 and the air volume switching means 1 is read, and the air volume mode is read. Abnormality determination switching means 4 outputs the abnormality determination rotation speed for each air volume mode as a determination signal to determine the abnormal state of The difference between the rotation speed and the abnormality determination rotation speed obtained by reading the determination signal from the abnormality determination switching means 2 is calculated, and when the difference remains at a predetermined value or more for a predetermined period of time, the abnormality signal is used to control the blower. The abnormality detecting means 3 outputs an output to the means 2.

The control operation in the control block of the air conditioner configured in this way will be explained using the control flowchart in FIG. ” and proceeds to step 102. In step 102, the set rotation speed RO of the blower motor 3 is set to, for example, “
Strong': Nl (r, I), l ), r Weak J: N
2 (r, p, n), 'Oa': N3 (r, p,
1, (Nl > N2 > N3), the blower motor 3 is driven and the process proceeds to step 103, the rotation speed R of the operating blower motor 3 detected by the rotation speed detection means 6 is read, and the process proceeds to step 104. .

In step 104, the set rotation speed RO and the rotation speed R during operation are determined.
It is determined whether the difference between the set rotation speed RO and the rotation speed during operation is greater than or equal to a predetermined rotation speed, for example, 20 Or, p, m. If R>RO, increase the energization width of the current waveform by θ1, if R=RO, do not change the energization width, and if R<RO, decrease the energization width by θ1 and step Return to 103. Conversely, if in step 104 the difference between the set rotational speed RO and the operating rotational speed R is greater than or equal to the predetermined rotational speed 200r, p, m, the process proceeds to step 106;
The abnormality detection means 5 sets a timer (t=O), proceeds to step 107, reads the operating rotation speed R, proceeds to step 108, and determines whether the timer has passed t1 seconds and is within t1 seconds. Then, the process proceeds to step 109, where the energization width is increased by e2, and the process proceeds to step 110.
pm or more, and the specified rotation speed is 200r.
If it is less than pm, the process returns to step 103, and conversely, if the predetermined number of rotations is 200 rpm or more, the process returns to step 107. On the other hand, when 30 seconds have elapsed, an abnormality signal is output to the blower control means 2 to perform protective control (for example, complete stop).

According to the embodiments described above, it is possible to determine an abnormality at each rotation speed below a predetermined rotation speed that is smaller than each set rotation speed, as shown in the abnormality determination area shown in FIG. 3, and to protect the blower motor in a timely manner. control is possible.

In this embodiment, the abnormality determination range is set to 200 rpm or less of each predetermined rotation speed, but considering that the higher the rotation speed of the blower motor, the larger the fluctuation range, the set rotation speed is If the predetermined rotation speed subtracted from the set rotation speed is increased as the rotation speed increases, more appropriate protection control can be performed.

In addition, in this example, when changing the current conduction width of the current waveform,
If the rotation speed during operation is larger than the set rotation speed minus the predetermined rotation speed, it is changed to ±O1, and if it is smaller, it is changed to ±02. All you have to do is

〔Effect of the invention〕

As described above, in the present invention, an abnormality is determined for each set rotation speed of the blower motor and protective control is activated. This enables timely abnormality detection and improves the reliability of the air conditioner. .

[Brief explanation of the drawing]

Fig. 1 is a control block diagram of the blower motor of an air conditioner according to an embodiment of the present invention, Fig. 2 is a control flowchart of the air conditioner, and Fig. 3 is the rotation speed of the blower motor of the air conditioner. FIG. 4 is a diagram showing an abnormality determination area corresponding to the rotation speed of a blower motor of a conventional air conditioner.

Claims (1)

[Claims] An air volume switching means for setting the air volume, a blower motor for rotating the blower, a rotation speed detection means for detecting the rotation speed of the blower motor and outputting a detection signal, and a rotation speed detection means corresponding to the air volume set by the air volume switching means. An air conditioner comprising a blower control means for controlling the rotation speed of the blower motor based on the difference between the set rotation speed of the blower motor and the rotation speed of the blower motor detected by the rotation speed detection means,
an abnormality determination switching means for setting an abnormality determination rotation speed based on the air volume set in the air volume switching means; a rotation speed of the blower motor detected by the rotation speed detection means; An air conditioner comprising an abnormality detection means that calculates a difference between the rotation speed and the abnormality determination rotation speed and outputs an abnormality signal when the difference continues to be equal to or greater than a predetermined value for a predetermined period of time.