JPH0222646B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a control device for a vacuum cleaner that detects and controls the suction air volume.

Conventional configuration and its problems Conventionally, as a means of detecting the suction air volume of a vacuum cleaner, an obstacle such as a wind catcher plate is installed in the ventilation path, and the suction air volume is detected by the force that this obstruction receives from the wind. I found a way. However, the airflow detection means generates turbulent airflow due to the presence of obstacles in the ventilation path, resulting in increased noise. In addition, since the air volume detection means detects the air volume through mechanical operation, losses due to frictional resistance of moving parts cannot be ignored, and there are drawbacks such as delay in response to minute changes in air volume and output hysteresis. It was something I had. Furthermore, there are other means for detecting the suction air volume by detecting the suction pressure of the vacuum cleaner and the voltage applied to the electric motor, and means for detecting the suction air volume from the rotation speed of the electric motor and the applied voltage of the electric motor. In this method, the voltage applied to the motor is an effective value, so when the motor is controlled by phase control or the like, it is difficult and difficult to detect the effective value of the voltage applied to the motor.

Purpose of the Invention In view of the above drawbacks, the present invention makes it possible to detect the suction air volume from the pressure inside the vacuum cleaner and the rotational speed of the electric motor, which is relatively easy to detect, and the suction air volume of the vacuum cleaner with a relatively easy configuration. This realizes a detection device. Moreover, by controlling the suction air volume of the vacuum cleaner to an optimal suction air volume according to the load, a vacuum cleaner with less wasteful output can be realized.

Structure of the Invention A suction pressure detection device for detecting suction pressure, a rotation speed detection device for detecting the rotation speed of an electric blower motor, and a detected pressure calculation for calculating and amplifying the output signal of the suction pressure detection device. a rotation speed calculation device that calculates and amplifies the output signal of the rotation speed detection device; a comparison calculation device that compares the outputs of the detected pressure calculation device and the rotation speed calculation device;
and an electric blower control device that controls the output of the electric blower so that the difference between the output value of the detected pressure calculation device and the output value of the rotation speed calculation device is always a set value, and It is designed to control the output of the blower.

DESCRIPTION OF THE EMBODIMENTS The embodiments will be described below with reference to FIGS. 1 to 3.

First, the operating principle of the present invention will be briefly explained using FIG. In the figure, the vertical axis of the graph is the suction pressure, and the horizontal axis is the vacuum cleaner motor rotation speed, Q ₁ to _{Q 4}
is the correlation line between the suction pressure and the motor rotation speed when the suction air volume of the vacuum cleaner is held constant. In normal use of a vacuum cleaner, the correlation lines Q ₁ to _{Q 4} can be approximated by almost straight lines, and the mutual spacing between the correlation lines is also approximately proportional to the suction air volume. Therefore, the suction air volume Q is given by the motor rotation speed N _M and the suction pressure V _P
Then, it can be found by the following formula.

Q=α・V _P +β・N _M +γ However, α, β, and γ are constants. As you can see from the above equation, the suction air volume of a vacuum cleaner is determined by the suction pressure.
It is obtained by calculation from V _P and motor rotation speed N _M. Therefore, the suction air volume of the vacuum cleaner can be easily detected by detecting the rotational speed of the electric motor and the suction pressure.

As described above, according to the present invention, the suction air volume of a vacuum cleaner, which has been difficult to detect in the past, can be easily detected with a simple configuration.

Next, Figure 2 is a concrete block diagram, in which 1 is an electric blower motor, 2 is a semiconductor pressure sensor, etc., which detects the suction pressure inside the vacuum cleaner and outputs an output proportional to the suction pressure. 3 is a rotation speed detection device composed of a cometer generator or the like that detects the rotation speed of the electric motor 1 and outputs an output proportional to the rotation speed; 4 is an output of the suction pressure detection device 2 and the rotation speed detection device; 3 is an arithmetic device that inputs the output, performs calculations, and outputs the result; 5 is an electric blower control device (hereinafter referred to as a control device) that controls the current of the motor and changes the output based on the output of the arithmetic device. Output of suction pressure detection device 2
The relationship between V _P1 , the output N of the rotation speed detection device 3, and the suction air volume Q is the same as that shown in Fig. 1, and Q=a・V _P1 +
It is found by b・N+c. Here, a, b, and c are constants, which are fixed depending on the characteristics of the vacuum cleaner. Therefore, if the calculation device 3 performs the calculation a·V _P1 +bN+c on the input V _P1 and N and outputs the result, the calculation device 4 will output an output proportional to the intake air volume. In this way, the suction pressure detection device 2, the rotation speed detection device 3, and the arithmetic device 4 constitute a suction air volume detection device. The control device 5 controls the output of the electric motor 1 according to the output of the arithmetic device 4 so that the suction air volume of the vacuum cleaner becomes a suction air volume suitable for the load.

In this manner, the above configuration makes it possible to control the suction air volume of the vacuum cleaner.

FIG. 3 is a specific circuit diagram. In the figure,
1 and 3 to 5 are the same as those in the embodiment shown in FIG. 2, 6 is a bidirectional three-terminal thyristor that controls the current of the motor 1, and 7 is the output of the rotation speed detection device 3, which is calculated and the result obtained. 8 is a detection pressure calculation device that inputs the output of the suction pressure detection device 2, performs calculations, and outputs the result. 9 is a detection pressure calculation device that outputs the output of the rotation speed calculation device 7 and the detection pressure calculation device 8. A comparison calculation device 10 inputs the output of the comparison calculation device 9 and calculates the difference between the output of the rotation speed calculation device 7 and the output of the detected pressure calculation device 8 by comparing the outputs and outputting an output proportional to the difference. This is a gate control device for controlling the output of the electric motor 1 so that

There is a relationship between the suction air volume, suction pressure, and motor rotation speed of a vacuum cleaner as shown in Figure ₁ . Similar to the embodiment shown in FIG _. 2, there is a relationship between Q=a ₁ ·V _N +b ₁ ·V _P1 +c ₁ . Here, a ₁ , b ₁ , and c ₁ are constants.

When changing the output of a vacuum cleaner depending on the load,
One effective method is to control the suction air volume to a constant level. If the optimal suction air volume value in this case is Qc, then the following equation always holds true if the vacuum cleaner is operated at a constant suction air volume Qc regardless of the load.

Qc - (a ₁ · V _N + b ₁ · V _P1 + c ₁ ) = 0 Furthermore, the rotation speed calculation device 7 performs a calculation of 1/a ₁ on the input value and outputs the result, and the detected pressure calculation device 8 calculates the input value. This calculation device is set to perform the calculation {V _P1 +(c ₁ -Qc)}/b for the input signal and output the result. Therefore, if the output of the rotation speed calculation device 7 is V _N1 and the output of the detection pressure calculation device 8 is V _P2 , then if the vacuum cleaner has a suction air volume of Qc regardless of the load, V _N1 = V. It is _P2 . Comparison calculation device 9 has V _N1 and
The gate control device 10 outputs a value proportional to the difference between V _P2 and controls the gate of the bidirectional three-terminal thyristor 6 to control the output of the motor so that the difference between V _N1 and V _P2 becomes 0. . Therefore, in the above configuration, since the output of the vacuum cleaner is controlled by the gate control device 10 so that V _N1 =V _P2 , the suction air volume becomes a constant suction air volume of Qc.

In this way, in the configuration shown in Figure 3,
By controlling the output of the vacuum cleaner so that the ratio between the rotational speed of the vacuum cleaner's motor and the voltage applied to the motor is constant, a constant suction air volume control device for a vacuum cleaner can be easily configured. Furthermore, in this case, the arithmetic unit 4 can be constructed from a simple amplification device and a comparison arithmetic device, making it an extremely practical circuit.

Effects of the Invention As described above, according to the present invention, the suction air volume of a vacuum cleaner does not have any effect on the ventilation path, and moreover, it can be reliably controlled using a highly stable detection device that does not have mechanical operating parts. Moreover, by operating the vacuum cleaner with an appropriate constant suction air volume, it is possible to always perform cleaning with an output suitable for the load, making it possible to realize a highly efficient vacuum cleaner.

[Brief explanation of drawings]

Fig. 1 is a characteristic diagram showing the correlation between suction air volume, suction pressure, and motor rotation speed in a vacuum cleaner, Fig. 2 is a block diagram of an embodiment of the present invention, and Fig. 3 is a circuit diagram of an embodiment of the present invention. be. 1...Electric motor, 2...Suction pressure detection device, 3...
...Rotation speed detection device, 4...Arithmetic device, 5...Electric blower control device, 7...Rotation speed calculation device, 8...
Detection pressure calculation device, 9... Comparison calculation device.

Claims (1)

[Claims] 1. A suction pressure detection device for detecting suction pressure, a rotation speed detection device for detecting the rotation speed of an electric blower motor, and a detected pressure calculation device for calculating and amplifying the output signal of the suction pressure detection device. , a rotation speed calculation device that calculates and amplifies the output signal of the rotation speed detection device, a comparison calculation device that compares the outputs of the detected pressure calculation device and the rotation speed calculation device,
A control device for a vacuum cleaner, comprising: an electric blower control device that controls the output of the electric blower so that the difference between the output value of the detected pressure calculation device and the output value of the rotation speed calculation device always becomes a set value.