JPS6349494B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vacuum cleaner, and its purpose is to improve the control response of an energy-saving vacuum cleaner that does not allow more than necessary input power to be passed to an electric blower.

Conventionally, there has been a device shown in FIG. 1 that increases the input voltage of an electric blower to compensate for a decrease in air volume due to clogging of the filter of a vacuum cleaner. That is, 101 is a case of the vacuum cleaner body, 102 is a filter, and an electric blower 103 is provided behind the filter. 104 is a hose,
A connection pipe 105 connects the case 101 and the hose 104. The dust-containing air sucked through the hose 104 is separated from dust by the filter 102, and purified air is discharged from the exhaust port 106. 107 is an air volume sensor provided between the front of the electric blower 103 and the filter 102. This function is as shown in FIG.
8 and operates the electric blower 103 with its output. As shown in FIG. 3, the configuration of the control circuit 108 is such that the output of the sensor 107 is used in a comparison circuit 109 to determine whether the air volume is appropriately large or small relative to a set value. When the output of the comparison circuit 109 is larger or smaller than the set value, the value in the storage circuit 110 is increased or decreased. Do not change when appropriate. Based on the value of this memory circuit 110, the input power control circuit 111
determines the input to the electric blower 103. sensor 1
07 has an electric blower 10 as shown in FIG.
It consists of a wind receiving plate 113 that is provided in front of the air filter 3 and pulled by a spring 112 for back pressure, and a variable resistor 114 connected to this wind receiving plate 113. The plate 113 rotates and issues a signal indicating a large air volume. On the other hand, when the air volume is low, it rotates in the opposite direction to the exhaust, giving a signal indicating that the air volume is low. While this signal is being output, the value in the memory circuit 110 continues to increase or decrease, and therefore the electric blower 1
The input power of 03 continues to increase or decrease during that time. When the air volume reaches the set value, the wind receiving plate 113 is at the proper position, and the value in the memory circuit 110 stops increasing or decreasing.
The input power to the electric blower 103 is maintained at the current value.

In the above configuration, the input power of the electric blower 103 is determined by the value of the memory circuit 110, and when the air volume is larger or smaller than the set value, the comparison circuit 109 determines the output of the sensor, and the output is used as the memory circuit. 1
Increase or decrease the value of 10. Therefore, since the value of the memory circuit 110 changes, the input power control circuit 11
The output of 1 increases or decreases. Therefore, electric blower 1
03's input power increases and decreases. When the air volume reaches the set value, the output of the comparison circuit 109 that compares and determines the output of the sensor 107 indicates that it is an appropriate value, and the value in the memory circuit 111 is not increased or decreased.
The input power of 03 is kept at the current input.

By the way, the sensor 107 is constructed by connecting a wind receiving plate 113 and a variable resistor 114, but the variable resistor 1
14 has rotational resistance, and when the air volume changes slightly, the difference in the force balance between the wind receiving plate 113 and the spring 112 is small and is smaller than the rotational resistance of the variable resistor 114, so the variable resistor 114 does not rotate. , the output of sensor 107 does not change. As described above, conventional sensors have the disadvantage that they have poor responsiveness and cannot be controlled in response to minute changes in air volume. In particular, as it is used, the lubrication of the rotating shaft of the variable resistor 114 becomes worse.
The drawback was that as the rotational torque increased, the operation became worse.

In order to eliminate this drawback, as shown in FIG. 5, a magnet 115 is attached to the wind receiving plate 113, and a reed switch 116 is attached to the electric blower 103 side to send a signal of high input, and a reed switch 117 is attached to the side opposite to the electric blower.
It has been considered that the wind receiving plate 113 is provided with a slider to prevent sliding resistance from being applied to the wind catcher plate 113 to make the movement smoother, but in this case, when the magnet 115 moves to a certain extent and approaches each reed switch, the reed switch does not move for the first time. Since it turns ON and outputs a signal indicating whether the input is large or small, the reed switch will not work until it moves to that point, and will not respond to minute changes in air volume.

The present invention aims to eliminate the above-mentioned drawbacks of the conventional art and ensure reliable control of the electric motor even with minute changes in air volume.
Only the parts different from the conventional example will be explained. If only the sensor portion is shown in FIG. 6, the upper end of the wind receiving plate 1 is rotatably provided in the intake side passage of the electric blower 3 via a shaft 2, and a magnet 4 is attached to the lower end thereof. The wind receiving plate 1 is pulled by a spring 5 toward the side opposite to the electric blower. A Hall element 6 is installed near the magnet 4, and the output of this Hall element 6 is connected to the control circuit as in the conventional example.

With the above configuration, when the air volume decreases below the set value, the wind receiving plate 1 is pulled toward the side opposite to the electric blower by the spring 5, and the magnet 4 approaches the Hall element 6. Therefore, the output of the Hall element 6 increases, The control circuit increases the input to the electric blower 3, and the air volume returns to the original level.
Conversely, if the floor nozzle separates from the floor and the air volume is too large, the wind receiving plate 1 is pushed by the wind and rotates toward the electric blower 3, and the magnet 4 moves away from the Hall element 6.
The output of the Hall element 6 decreases. For this reason, the control circuit reduces the input to the electric blower 3, restores the air volume to the original value, and cuts out unnecessary power.

Conventionally, a variable resistor was used in the sensor part, so there was sliding resistance during rotation, and the wind receiving plate did not move when there was a small change in air volume.However, according to the present invention, the position can be detected without contact. Since there is no sliding resistance, the wind receiving plate moves even with small changes in air volume, resulting in very good responsiveness.
Furthermore, although conventional non-contact reed switches have no sliding resistance, they do not respond to minute changes in air volume until the magnet moves to the sensitive part of the reed switch.

FIG. 7 shows the relationship between the air volume and vacuum degree of a vacuum cleaner using such a sensor. In Fig. 7, A shows the case where the conventional variable resistor is used, and B shows the case of the present invention. Conventionally, when the air volume goes from large to small, and when it goes from small to large, the air volume deviates by the amount of sliding resistance. However, in the case of the present invention, no deviation occurs. As described above, according to the present invention, the set air volume can always be kept constant, which is economical and also ensures the air volume necessary for cleaning.

In the above embodiments, the sensor has been described on the intake side of the electric blower, but it may be provided anywhere as long as the wind is flowing, for example, it may be provided on the exhaust side.

As described above, according to the present invention, by configuring the airflow sensor with a wind receiving plate, a magnet, and a Hall element, the airflow can be always controlled to a constant airflow, and the filter eyes are clogged with dust. When the floor nozzle is away from the floor, the air volume can be kept constant and unnecessary electricity can be cut, which is effective. There is something big about it.

[Brief explanation of drawings]

Figure 1 is a schematic sectional view of a conventional vacuum cleaner, Figures 2 and 3 are block diagrams of its control circuit,
4 and 5 are side views of the airflow sensor, FIG. 6 is a side view of the airflow sensor showing an embodiment of the present invention, and FIG. 7 is a side view of the airflow sensor.
The figure is a characteristic diagram. 1... Wind receiving plate, 3... Electric blower, 4... Magnet, 6... Hall element.

Claims (1)

[Claims] 1. A sensor that detects the air flow rate in the air passage, a comparison circuit that compares the output of this sensor with a set value, a memory circuit that increases or decreases a stored value based on the output of this comparison circuit, and this memory circuit. The sensor is equipped with an input power control circuit that determines the input to the electric blower based on the stored value of A vacuum cleaner equipped with a Hall element whose output changes continuously.