JP2010265828A - Fan device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect the abnormality of a fan device, by detecting a state of being supposed to generate abnormal nose from the fan device. <P>SOLUTION: A magnet 303 is installed to the impeller 302 of the fan device, and a Hall element 304 is arranged on an opposed part. Vibration as a factor of abnormal noise of the fan device is detected by detecting the rotation control of the impeller and a variation condition of a position by the Hall element. When detecting that the fan device is abnormal through the variation condition of the position of the impeller 302, a trial is made so as to return to a normal state by stopping the driving of the fan device or driving at a low speed. Abnormality is also informed to a user. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fan device mounted on a copying machine or the like.

  Conventionally, various techniques for detecting an abnormality of a fan in a fan driving circuit that drives a fan by a motor have been proposed.

  For example, in the technique of Patent Document 1, an abnormal rotational speed that is uniquely determined from the rotational speed specifying means is calculated, and if the motor rotation becomes equal to or lower than the abnormal rotational speed, it is determined that the fan is abnormal.

  In the technique of Patent Document 2, the winding current value for driving the fan is stored, and the life of the fan is detected by always comparing it with the previous time.

  In the technique of Patent Document 3, the life of the fan is detected based on the number of rotations by the Hall element and the winding current value of the motor.

JP 2003-111475 A JP 2003-023792 A Japanese Patent Laid-Open No. 2003-111478

  However, in the conventional fan driving circuit, there is no technique for detecting the fan noise and stopping the fan when the noise is abnormally high. This is because it is difficult to determine whether the noise is noise generated by the fan. That is, it is difficult to directly detect noise generated by the fan. Therefore, a fan noise detection method that considers the cause of fan noise generation can be considered.

  The main cause of fan noise is the inclination of the impeller. The inclination of the impeller portion is caused by various factors. For example, it may occur during a manufacturing process such as shaft collapse or impeller assembly failure, during assembly of a fan into a device, or loosening of the impeller portion press-fitting portion due to a specified temperature condition.

  When the technique of Patent Document 1 is used, the rotational speed of the motor does not decrease due to the inclination of the impeller portion, and therefore it is impossible to detect fan noise by the method of Patent Document 1.

  Further, even when the technique of Patent Document 2 is used, it is difficult to detect fan noise. That is, the winding current value of the motor is about several hundred milliamperes, but the change in the winding current value of the motor is about several milliamperes due to the generation of fan noise, and the detection error becomes larger.

  In view of the above-described conventional problems, the present invention can detect a state in which abnormal noise is generated from the device based on how the position of the impeller portion varies and accurately detect the device abnormality. An object is to provide a fan device.

  In order to achieve the above object, a fan device of the present invention includes an impeller portion for blowing air, a drive portion for rotationally driving the impeller portion, a magnet attached to the impeller portion, and movement of the magnet. At least one hall element for detection, angular velocity detection means for detecting the angular velocity of the impeller section from each output of the hall element, and the impeller by the drive section based on the detection result of the angular velocity detection means Generated by the movement of the magnet, the means for controlling the rotational drive of the part, the maximum value detecting means for detecting the maximum value of the output during the angular velocity based on the output of the Hall element generated by the movement of the magnet, and the magnet A minimum value detecting means for detecting a minimum value of the output during the angular velocity based on the output of the Hall element; an output of the maximum value detecting means; and a minimum value detecting means Difference detecting means for detecting a difference from the force, and means for controlling the driving unit to stop the rotational driving of the impeller unit when the output of the difference detecting unit exceeds a predetermined value. Features.

  Further, the fan device of the present invention includes at least one impeller portion for blowing air, a drive portion that rotationally drives the impeller portion, a magnet attached to the impeller portion, and a movement of the magnet. Based on the Hall element, the angular velocity detecting means for detecting the angular velocity of the impeller section from each output of the Hall element, and the detection result of the angular velocity detecting means, the rotational driving of the impeller section by the driving section is first or A means for controlling at a second speed; a maximum value detecting means for detecting a maximum value of an output in an angular velocity based on an output of the Hall element generated by the movement of the magnet; and a movement of the magnet. A minimum value detecting means for detecting a minimum value of the output during the angular velocity based on the output of the Hall element; an output of the maximum value detecting means; and an output of the minimum value detecting means; Difference detection means for detecting a difference, and speed for controlling the drive section so that the rotational drive speed of the impeller section is switched to the first speed or the second speed according to the output of the difference detection means And a switching control means.

  According to the present invention, it is possible to detect a state in which abnormal noise is generated from the fan device based on how the position of the impeller portion varies, and it is possible to accurately detect abnormality of the fan device. Become.

It is sectional drawing which shows the structure of the fan apparatus in embodiment. It is a block diagram which shows the structure of the control system of the fan apparatus in embodiment. It is a conceptual diagram which shows the change of the output of a Hall element which changes according to the moving direction of the permanent magnet with respect to a Hall element. It is a wave form diagram which shows each output via a comparator from the output addition part in FIG. It is a wave form diagram which shows each output via the difference detection part from the output addition part in FIG. It is a flowchart which shows the control flow which concerns on 1st Embodiment. It is a flowchart which shows the control flow which concerns on 2nd Embodiment. It is a flowchart which shows the control flow which concerns on 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
<Configuration of fan device>
First, the mechanism of the fan device and the configuration of the control system in the present embodiment will be described with reference to FIGS.

(A) Mechanism of Fan Device FIG. 1 is a cross-sectional view showing a configuration of a fan device according to an embodiment of the present invention.

  This fan device has an impeller portion 302 for air blowing in which a rotating shaft 301 is fixed at the center. The rotation shaft 301 passes through the substrate 305 and is fixed to the motor 306 (drive unit). A permanent magnet 303 is attached to the surface of the impeller portion 302 on the substrate 305 side, and a Hall element for detecting the movement of the magnet 303 at a position facing the magnet 303 on the surface of the substrate 305 on the impeller portion 302 side. At least one 304 is attached.

(B) Configuration of Control System FIG. 2 is a block diagram showing the configuration of the control system of the fan device in the embodiment.

  The control system of the fan device includes an output adding unit 102, a comparator 104, an edge detecting unit 105, and an angular velocity detecting unit 106.

  The output adder 102 receives and adds the outputs Hout of the Hall elements 304.

  The comparator 104 compares the reference voltage VF with the output of the output adding unit 102. The comparator 104 generates a reference signal for detecting the angular velocity of the impeller unit 302 from the output of the Hall element 304. The output of the comparator 104 is input to the edge detection unit 105.

  The output of the angular velocity detection unit 106 is input to the CPU 107. If the angular velocity detection result is larger than the target angular velocity, the CPU 107 controls the speed of the motor 306 in the deceleration direction, and conversely if it is smaller, performs the speed control in the acceleration direction.

  On the other hand, the output of the output adding unit 102 is input to the maximum value detecting unit 108 and the minimum value detecting unit 109, and the outputs of the maximum value detecting unit 108 and the minimum value detecting unit 109 are input to the difference detecting unit 110.

  The maximum value detection unit 108 detects the maximum value of the output during the angular velocity generated when the magnet 303 moves on the Hall element 304. The minimum value detection unit 109 detects the minimum value of the output during the angular velocity generated when the magnet 303 moves on the Hall element 304. Then, the difference detection unit 110 detects the difference between the output of the maximum value detection unit 108 of the Hall element 304 and the minimum value detection unit 109. The output of the difference detection unit 110 is input to the CPU 107.

  The CPU 107 controls the rotation drive of the motor 306 by the motor drive circuit 111 based on the output of the angular velocity detection unit 106 and the output of the difference detection unit 110.

<General characteristics of Hall element 304>
Next, general characteristics of the Hall element 304 will be described with reference to FIG.

  FIGS. 3A and 3B are conceptual diagrams showing changes in the output of the Hall element that change in accordance with the direction of movement of the permanent magnet 303 relative to the Hall element 304. 3A shows a case where the permanent magnet 303 is moved in the horizontal direction with respect to the Hall element 304, and FIG. 3B shows a case where the magnet 303 is moved in the vertical direction with respect to the Hall element 304. ing.

  The output of the Hall element 304 changes according to the magnetic flux density. As shown in FIG. 3A, when the center Pa of the permanent magnet 303 is used as a reference, the amplitude from the reference of the Hall element 304 increases as the two poles are approached. That is, as the S pole of the magnet 303 is approached, the output of the Hall element 304 increases in the plus direction, and conversely, as the N pole is approached, the output increases in the minus direction.

  Therefore, when the magnet 303 moves in the horizontal direction with respect to the Hall element 304, an output like an AC waveform whose output peaks when the poles of the Hall element 304 and the magnet 303 approach is obtained (see FIG. 3A). .

  From the above, as shown in FIG. 3B, when the magnet 303 is moved in the vertical direction and moved away from the Hall element 304 and moved away from the Hall element 304, the magnet 303 is moved in the horizontal direction. As shown in b), the amplitude of the AC waveform described above increases and decreases. That is, when the magnet 303 is close to the Hall element 304, the amplitude is large, and conversely, when the magnet 303 is far, the amplitude is small.

<Output from Output Adder 102 via Comparator 104>
4A and 4B are waveform diagrams showing respective outputs from the output adder 102 in FIG. 2 via the comparator 104. FIG. 4A is an output waveform of the output adder 102, and FIG. (B) shows the output waveform of the comparator 104.

  When the Hall element 304 and the magnet 303 approach, the output of the output adding unit 102 varies. VF in FIG. 4A is the reference voltage shown in FIG. The comparator 104 compares the reference voltage VF and the output of the output adder 102, thereby outputting a comparator output as shown in FIG. When the output of the output adder 102 is larger than the reference voltage VF, the “H” level is output to the comparator output.

  Eout in FIG. 4B is an output of the edge detection unit 105 in FIG. 2 and detects a rising edge of the comparator output Cout. Although only the rising edge is shown in the example of FIG. 4B, there is no problem even with the falling edge. Kout in FIG. 4B is an output of the angular velocity detection unit 106 in FIG. 2, and this output Kout is input to the CPU 107 and used to measure the time between the edge detection outputs Eout.

<Output from Output Adder 102 via Difference Detector 110>
5A, 5B, and 5C are waveform diagrams showing respective outputs from the output adding unit 102 in FIG. 2 via the difference detecting unit 110. FIG. 4A shows the output waveform of the output adding unit 102, FIG. 4B shows the output waveform of the difference detecting unit 110, and FIG. 4C shows the state of the impeller unit 302 corresponding to these output waveforms. Show.

  As shown in FIG. 5C, when the impeller unit 302 moves up and down, the amplitude of the output Aout of the output adder unit 102 obtained by adding the output Hout of the Hall element 304 fluctuates, increases or decreases. The maximum value detection unit 108 outputs the maximum value as the maximum value detection output Mout, and the minimum value detection unit 109 detects the minimum value as the minimum value detection output Sout. The difference detection unit 110 outputs a difference output between these detection outputs as a difference detection output Dout.

  The difference detection output Dout is input to the CPU 107 and is always compared with predetermined comparison values 1 and 2 therein. The CPU 107 compares the difference detection output Dout with the comparison value 1 and the comparison value 2, respectively, and confirms whether the difference detection output Dout is within the range between the comparison value 1 and the comparison value 2.

  If it is not within the range, the CPU 107 determines that the fan device is abnormal, and if it is within the range, determines that the fan device is normal. This is because when the impeller part 302 is out of the range, the state of the impeller part 302 is abnormal, that is, as shown in FIG. 5C, the impeller part 302 is moved up and down, and the Hall element 304 and the magnet 303 are approached or moved away. Means. When such an abnormality occurs, abnormal noise of the fan device is generated.

  In the present embodiment, the comparison value 1 and the comparison value 2 and two comparison values (an example of a predetermined value) are provided and the range is normal. However, the present invention is not limited to this. For example, it is possible to have one comparison value and judge whether the comparison value is larger or smaller. Further, the configuration is such that the determination is made inside the CPU 107, but the present invention can also be implemented by making a determination using a circuit such as a comparator.

<Control flow according to the first embodiment>
Next, a control flow according to the first embodiment will be described with reference to FIG.

  FIG. 6 is a flowchart showing a control flow according to the first embodiment.

  First, in step S402, the CPU 107 determines whether or not to drive the fan device. If it is driven, the process proceeds to step S403. In step S403, the CPU 107 compares whether the angular velocity obtained from the angular velocity output Kout is greater than the target velocity. If it is larger than the target speed, that is, if the rotation of the motor 306 is too fast, the process proceeds to step S404 and the motor 306 is decelerated, and conversely if it is smaller than the target value, that is, if the rotation of the motor 306 is too slow, the process proceeds to step S405. Acceleration control of the fan device is performed.

  When the processes of step S404 and step S405 are finished, the process moves to step S406.

  In step S406, the CPU 107 determines whether or not the difference value obtained from the difference detection output Dout is larger than the comparison value 2 (see FIG. 5B). If the difference value is larger than the comparison value 2, the process proceeds to step S407, and if smaller, the process proceeds to step S408. In step S407, the CPU 107 confirms whether the difference value is smaller than the comparison value 1 (see FIG. 5B).

  In step S406 and step S407, when the CPU 107 confirms that the difference value is smaller than the comparison value 1 and larger than the comparison value 2, the CPU 107 determines that the fan device is normal, that is, the fan impeller 302 is in the correct position. Then, the process returns to step S403 to execute the normal speed control sequence. Conversely, if the difference value is outside the range between the comparison value 1 and the comparison value 2, it is determined that the fan device is abnormal, and the fan device is stopped in step S408.

<Advantages of First Embodiment>
According to the first embodiment, the state of the impeller unit 302 of the fan device is detected by the Hall element 304, and the position of the impeller unit 302 is detected together with the speed control. And if the abnormality of the position of the impeller part 302 is detected, the drive of a fan apparatus will be stopped. That is, by detecting an abnormality in the position of the impeller unit 302, it can be determined that the fan device vibrates and abnormal noise is generated, and the driving of the fan device can be stopped.

[Second Embodiment]
In the second embodiment, it is considered that even if it is detected that the fan device is abnormal due to a change in the position of the impeller unit 302, it may be in a normal state if driven at a low speed. Take control. It differs from the first embodiment only in the control flow, and the configuration is the same.

<Control flow according to the second embodiment>
FIG. 6 is a flowchart showing a control flow according to the second embodiment.

  First, in step S <b> 702, the CPU 107 sets a predetermined target value 1 as a target value for the rotational speed of the motor 306. The subsequent processing from step S703 to step S708 is the same as the processing from step S402 to step S407 in FIG. 4 in the first embodiment described above.

  If the difference value is outside the range of the comparison value 1 to the comparison value 2 and it is determined that the fan device is abnormal, the process proceeds to step S709.

  In step S709, the CPU 107 confirms whether or not the current target speed is the target value 1. If the target speed is 1, the process proceeds to step S710, the rotation speed of the motor 306 is set to the target speed 2, and the process proceeds to step S704. In the present embodiment, the rotational speed of the target speed 2 is set smaller than the target speed 1. Usually, it is rotated at a high speed setting (target speed 1: example of first speed). At that time, if it is detected that the fan device is abnormal due to the position fluctuation of the impeller 302, the motor 306 is driven at a low speed setting (target speed 2: an example of the second speed). It may be within the range of the value 1 to the comparison value 2. Therefore, the current target speed is confirmed in step S709, and if it is a high speed setting (target speed 1), control is performed by switching to a low speed target (target speed 2) (speed switching control). On the other hand, when the speed has already been changed to the target speed 2, the process proceeds to step S711, the fan device stop process is executed, and an abnormal stop is performed in step S712.

<Advantages of Second Embodiment>
According to the second embodiment, there are advantages equivalent to those of the first embodiment. In addition, when it is detected that the fan device is abnormal due to the fluctuation of the position of the impeller 302, it is possible to return to a normal state by driving at a low speed, thereby preventing an unnecessary abnormal stop. Can do.

[Third Embodiment]
In the third embodiment, a control example in the case where the fan device is applied to a device such as a copying machine that particularly requires waste heat will be described.

  Only the control flow is different from the first and second embodiments, and the configuration is the same.

<Control flow according to the third embodiment>
FIG. 8 is a flowchart showing a control flow according to the third embodiment.

  In the CPU 107, the processing from step S802 to step S810 is the same as the processing from step S702 to step S710 of FIG. 7 in the second embodiment described above.

  In step S810, the driving of the motor 306 is switched to the target speed 2 and the process proceeds to step S811. In step S811, the user is notified that an abnormality has occurred (abnormality notification), and the process proceeds to step S812.

  In step S812, the CPU 107 sets the operation of the copying machine to the down mode, and proceeds to step S804. Because the fan device is abnormal and changed to a low speed setting, the exhaust capacity or cooling capacity in the copier is reduced. As a result, the normal operation of the copying machine may affect the power supply, heat generating components, and the like. For this reason, it is necessary to operate the copying machine in a down mode (= productivity reduction, etc.) that does not affect the power supply, heat-generating components, etc., unlike when the fan device is driven at full speed.

  If the target speed 2 has already been set in step S809, the fan device is stopped in step S813, and the process proceeds to step S814. In step S814, the user is notified of the abnormality of the fan device, and in step S815, the abnormality is stopped and the sequence is terminated.

<Advantages of Third Embodiment>
According to the third embodiment, there are advantages equivalent to those of the first embodiment. Also, when applied to the operation of a device that requires waste heat, such as a copying machine, an appropriate operation can be performed on the device when an abnormality of the fan device is detected.

[Other embodiments]
In the first, second, or third embodiment, when the rotational speed of the motor 306 is not within the control range, a function of stopping the control as an error of the fan device may be added.

DESCRIPTION OF SYMBOLS 102 Output addition part 104 Comparator 105 Edge detection part 106 Angular velocity detection part 108 Maximum value detection part 109 Minimum value detection part 110 Difference detection part 301 Rotating shaft 302 Impeller part 303 Magnet 304 Hall element 305 Substrate 306 Motor

Claims (6)

An impeller for blowing air,
A drive unit for rotationally driving the impeller unit;
A magnet attached to the impeller portion;
At least one Hall element for detecting movement of the magnet;
Angular velocity detection means for detecting the angular velocity of the impeller portion from each output of the Hall element;
Means for controlling the rotational drive of the impeller by the drive based on the detection result of the angular velocity detector;
Maximum value detecting means for detecting the maximum value of the output during the angular velocity based on the output of the Hall element caused by the movement of the magnet;
Minimum value detecting means for detecting the minimum value of the output during the angular velocity based on the output of the Hall element caused by the movement of the magnet;
Difference detection means for detecting a difference between the output of the maximum value detection means and the output of the minimum value detection means;
A fan device comprising: means for controlling the drive unit to stop the rotation of the impeller unit when the output of the difference detection unit exceeds a predetermined value. An impeller for blowing air,
A drive unit that rotationally drives the impeller unit;
A magnet attached to the impeller portion;
At least one Hall element for detecting movement of the magnet;
Angular velocity detection means for detecting the angular velocity of the impeller portion from each output of the Hall element;
Based on the detection result of the angular velocity detection means, means for controlling the rotational drive of the impeller part by the drive part at a first or second speed;
Maximum value detecting means for detecting the maximum value of the output during the angular velocity based on the output of the Hall element caused by the movement of the magnet;
Minimum value detecting means for detecting the minimum value of the output during the angular velocity based on the output of the Hall element caused by the movement of the magnet;
Difference detection means for detecting a difference between the output of the maximum value detection means and the output of the minimum value detection means;
Speed change control means for controlling the drive unit so that the rotational drive speed of the impeller unit is switched to the first speed or the second speed according to the output of the difference detection means. Features a fan device.   3. The fan according to claim 2, wherein the speed switching control unit controls the impeller unit to rotate at the first speed when the output of the difference detection unit is smaller than a predetermined value. apparatus.   3. The fan according to claim 2, wherein the speed switching control unit controls the impeller unit to rotate at the second speed when the output of the difference detection unit is larger than a predetermined value. apparatus.   4. The fan device according to claim 2, wherein the second speed is lower than the first speed. An abnormality notification means for notifying the user of an abnormality is provided,
6. The fan device according to claim 1, wherein when the output of the difference detection unit exceeds a predetermined value, the abnormality notification unit notifies the user of the abnormality.