JPH044886B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a dust detection device for a vacuum cleaner that detects dust passing through an air passage of the vacuum cleaner.

BACKGROUND ART Generally, a conventional dust detection device for a vacuum cleaner has a configuration as shown in Japanese Utility Model Application Publication No. 195660/1983. In FIG. 11, a light emitting diode 101 is provided in a suction passage 111 extending from a floor suction port 109 of a vacuum cleaner to a suction port 110 of a vacuum cleaner body 108, a photodiode 102 is provided opposite to this light emitting diode 101, and a photodiode 102 is provided opposite to the light emitting diode 101. It was receiving light from the light emitting diode 101. This photodiode 102 is connected to the suction passage 111 during cleaning work.
If a large amount of dust is contained in the suction air flowing through the photodiode 101, the light from the light emitting diode 101 will be blocked by the dust, and the amount of light received by the photodiode 102 will decrease, resulting in a small output. As a result, the 10th
A transistor 103 connected to the base of the photodiode 102 shown in the figure is turned off.
This turns off the next stage transistor 104.
The transistors 105 and 106 are turned on, and the light emitting diode 107 serving as the display section is turned on. This light emitting diode 107
When lit, it indicates that dirt is being sucked in, and the worker continues cleaning work. Also, when there is no dust in the suction air flow, photodiode 1
Since the amount of light received by 02 increases and the output increases, transistors 103 and 104 turn on, and transistor 10
5,106 turns off and the light emitting diode 107
goes out. This turning off of the light emitting diode 107 means that there is no more dust to be sucked.
The workers were to finish the cleaning work.

Problems to be Solved by the Invention However, in the conventional dust detection device for a vacuum cleaner, a light emitting diode 101 and a photodiode 102, which are detectors for optically detecting dust, etc.
Since each of these is performed by a single unit, depending on the position where the dust passes between the two detectors, the photodiode 102
Since the amount of light received differs, the display level (brightness) of the light emitting diode 107 varies, resulting in a problem that display cannot always be performed at a constant level. Furthermore, since the switching operation of the transistor 103 is utilized, if a predetermined amount or size of dust does not pass between the quantity detectors, the output of the photodiode 102 is switched to the transistor 103.
Since the amount of dirt flowing through the suction passage 111 cannot be displayed with high accuracy, the amount of dirt flowing through the suction passage 111 cannot be displayed with high accuracy, and the display can only be made at the moment when the dirt has passed, so that the cleaner can perform appropriate cleaning work. However, there is a problem in that it is not possible to accurately determine whether the Furthermore, since the display is performed intermittently, there is a problem in that the dust detection display may be missed. In addition, light emitting diode 1
Since dust is detected individually, there is little opportunity for dust to block the light from the light emitting diode, and the presence or absence of dust cannot be accurately detected.

In view of the above-mentioned problems, the present invention detects dust sucked into a vacuum cleaner with high precision, displays the detection results continuously or in stages, allows the operator to make accurate judgments, and displays the detection results. The purpose is to prevent overlooking.

Means for Solving the Problems In order to achieve the above object, the present invention includes a light emitting section consisting of a plurality of light emitting elements that emit light into an air passage through which dust flows, and a light emitting section that receives light from the light emitting section. A light receiving section is provided which outputs a signal according to the amount, the signal from the light receiving section is outputted to a display section via a time constant circuit, and a display is displayed on the display section according to the magnitude of the output from the time constant circuit. It is configured to do so.

Effect In the above configuration, by providing a time constant circuit, the display continues for a certain period of time even after the dust has passed, so it is possible to eliminate misjudgments and missed displays due to differences in the display level by the cleaner. . Furthermore, since light is emitted by a plurality of light emitting elements, the chance that dust blocks the light from these light emitting elements increases dramatically, and the accuracy of determining the presence or absence of dust can be improved.

Embodiment An embodiment of the present invention will be described based on FIGS. 1 to 9.

As shown in FIG. 1, the dust detection device for a vacuum cleaner in this embodiment is provided with a light emitting section 1 and a light receiving section 2 that are supplied with power from a power supply section 3. The light emitting section 1 and the light receiving section 2 are provided opposite to the dust air passage. The output from the light receiving section 2 is amplified by the amplification section 4 and then sent to the display section 5 and the alarm section 6.
is output to.

Next, a unit equipped with a light emitting section 1 and a light receiving section 2 installed in an air passage will be explained with reference to FIG. The light emitting section 1 includes a plurality of infrared light emitting diodes 7a.
~7c, and the brightness is changed depending on the mounting position. That is, as shown in FIG. 3, a plurality of infrared light emitting diodes 7a, 7b, 7c are connected in series and parallel, and resistors 14, 15, 16 of different values are connected.
are connected to each other, and constant current control is performed using resistors 17 and 18, a Zener diode 19, and a transistor 20. In addition, the light receiving section 2 uses a surface-receiving photodiode 8, and the light emitting section 1 and the light receiving section 2 are connected to the dust passing section 1.
The light from the infrared light emitting diodes 7a, 7b, and 7c is condensed by a lens 11, passes through a dust passage section 14, and then passes through a slit 10 and a visible light blocking filter 9. and reaches the photodiode 8. Further, a reflection plate 12 is provided on the inner surface of the dust passage section 14 so that the intensity of light from the dust passage section 14 is uniform.

The output change of the photodiode 8 that detects the light is caused by blocking the light of the infrared light emitting diodes 7a, 7b, and 7c when the dust passes through the dust passing section 14, and the change occurs through the resistor 22 and transistor 23. It appears as a voltage across the resistor 24. The voltage is then stabilized using resistors 29 and 32, diodes 27 and 28, and transistors 30 and 31, and the voltage at point c is obtained as the output of light receiving section 2. resistance 25,
26 is for biasing the transistor 23, and the capacitor 21 is for noise prevention.

As shown in FIG. 5, the configuration of the widening section 4 is such that the output point c (FIG. 4) of the light receiving section 2 is received by a capacitor 33,
Only the alternating current component is taken out and amplified using resistors 39 and 40 and an amplifier 45. Furthermore, the resistor 42,4
3, 44, is amplified by an amplifier 46, and an amplified voltage is generated at point D. Resistors 35 and 36 are the first stage amplifier 4
5, resistors 37 and 38 provide bias for the next-stage amplifier 46, respectively. The resistor 41 and the capacitor 34 are used to maintain the output of the first stage amplifier 46 at a predetermined order constant.

Note that the switch 83 is for switching the degree of amplification.

As shown in FIG. 6, the display section 5 has a configuration in which the voltage at the output point D (FIG. 5) of the amplifying section 4 is received by a capacitor 48, only the alternating current component is taken out, and the resistor 51,
The potentials obtained at 52, 53, and 54 and the comparator 5, respectively.
Compare with 5, 56, 57, LED 58, 59, 6
0 lights up. Resistors 49 and 50 provide a bias to the signal, and resistors 62 and 63, a Zener diode 61, and a transistor 64 are used to drive the LED lighting.

As shown in FIG. 7, the configuration of the alarm section 6 is as shown in FIG.
, take out only the AC component, and connect the resistor 65,6
6, 68, 72, transistors 69, 70, and capacitor 67 perform signal processing, and resistors 72 and 73
A comparator 74 compares the voltage with a predetermined voltage obtained in the above, and causes a buzzer 79 to sound via resistors 76, 77, 79 and a transistor 78.

The power supply section 3 provides driving power to each section, and applies a ground to point A and a positive voltage to point B shown in each section. As shown in FIG. 8, the configuration of this power supply unit 3 is that a commercial power source 85 is passed through a switch 80 and a line filter 81, stepped down by a transformer 82, rectified by a diode bridge, and then stabilized by a three-terminal regulator 84. Convert to power source.

As shown in FIG. 9, the dust detection device for a vacuum cleaner with the above configuration is connected to a main body 91 of the vacuum cleaner, and has an air intake passage 92 which is an air passage through which dust passes.
A unit (FIG. 2) consisting of a light emitting section 1 and a light receiving section 2 is attached in the middle of the light emitting section.

To explain the operation in the above configuration, if dust is contained in the suction air during cleaning with a vacuum cleaner, the light from the infrared light emitting diodes 7a to 7c is blocked by the dust when passing through, and the photo The amount of light received by the diode 8 decreases, and the output point C of the light receiving section
The potential of decreases. Therefore, when dust passes intermittently, the output point C changes intermittently accordingly. Moreover, if the amount of passing dust is large, the amount of blocking the photodiode 8 will be large, and the amount of change in the output point C will also be large. Then, the signal at the output point C passes through the capacitor 33 of the amplifying section 4, and the potential change is taken out and amplified. The amplified signal appears in the potential at point D of the amplifying section 4, and the greater the potential change at the output point C of the light receiving section 2, the greater the potential change at the signal point D after amplification. Furthermore, the signal at point D is outputted via the capacitor 48 of the display unit 5, and the potential change is taken out,
5, 56, and 57, and LEDs 58, 59, and 60 are sequentially turned on in accordance with the change in the signal at point D. Similarly, the alarm buzzer 79 can be sounded by extracting the signal change at point D using the capacitor 48.
By sequentially turning on the transistors 69 and 70 and returning the circuit to the side opposite to the point D of the capacitor 48 via the capacitor 67, the time during which the transistor 70 is turned on is determined. A buzzer 79 is made to sound based on the comparison with the potential.

By the way, the infrared light emitting diodes 7a, 7b, 7
A plurality of photodiodes c are provided, and surface-receiving photodiodes 8 are arranged facing each other, and an infrared light emitting diode 7 is provided.
A, 7b, 7c and the photodiode 8 are provided with a lens 11 to condense the light, thereby creating a dust passage path 1.
The photodiode 8 is shielded from light no matter where on the cross section of the photodiode 4 the dust passes. Further, the brightness of the plurality of infrared light emitting diodes 7a, 7b, 7c is changed depending on their positions, and the brightness of the one located in the center is increased, and a reflective plate 12 is provided on the inner surface of the dust passageway 14. Dust passage path 1
The intensity of the light inside the photodiode 4 is made to be constant, and the change in the photodiode 8 is made to be constant if it is the same type of dust. Further, a slit 10 and a visible light cut filter 9 are provided in front of the photodiode 8 to reduce noise caused by external light and the like.

A capacitor 34 and a resistor 41 are provided at the output of the first stage amplifier 45, a predetermined time constant is provided, and the output of the first stage amplifier 45 is held for a predetermined time.
Also, the lighting and operating time of the buzzer 79 is increased.

In addition, by providing a sensitivity changeover switch 47 and changing the degree of amplification using resistors 43 and 44, the LEDs 58 to 60
It is possible to change the lighting level and the level at which the buzzer 79 sounds, and for example, it is possible to set it so that it does not display on the hair of the dog.

In this way, it is possible to display and alarm no matter where in the cross-section of the dust passageway 14 the dust passes, and the display level is changed in stages according to the amount of passing dust to notify the amount of dust. The display will disappear once the dust is gone, allowing you to know when the cleaning work is complete. Furthermore, since the display remains lit for a predetermined period of time although dust passes through instantly, it is possible to eliminate misjudgments and missed displays.

Effects of the Invention As is clear from the above embodiments, according to the present invention, since a plurality of light emitting elements emit light to dust passing through the air passage, the chances of detecting dust passing through the air passage are increased. It is possible to improve the detection accuracy of perilla dust. In addition, since a time constant circuit is provided, even if the amount or size of dust differs, it can be displayed continuously or in stages, making it possible for cleaners to avoid overlooking the display or misjudging cleaning work due to differences in the display level. In addition, it is possible to properly clean areas that are not visible to the naked eye only by displaying them.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a dust detection device for a vacuum cleaner which is an embodiment of the present invention, Fig. 2 is a sectional view of a unit equipped with a light emitting part and a light receiving part in the same dust detection device, and Fig. 3 is the same. A circuit diagram of the light emitting part in the dust detection device, Fig. 4 is a circuit diagram of the light receiving part in the same dust detection device, Fig. 5 is a circuit diagram of the widening part in the same dust detection device, and Fig. 6 is a display in the same dust detection device. Fig. 7 is a circuit diagram of the alarm part of the same dust detection device, Fig. 8 is a circuit diagram of the power supply part, Fig. 9 is a front view of a vacuum cleaner with the same dust detection device attached, Fig. 10 The figure is a circuit diagram of a conventional dust detection device for a vacuum cleaner, and FIG. 11 is a sectional view of a main part of the vacuum cleaner to which a light emitting device and a light receiving device are attached in the conventional dust detection device. 1... Light emitting section, 2... Light receiving section, 3... Power supply section,
4... Widening part, 5... Display part, 6... Alarm part, 7
a, 7b, 7c...Infrared light emitting diode, 8...
Photodiode, 11...lens, 12...reflector, 58, 59, 60...CED, 79...buzzer.

Claims (1)

[Scope of Claims] 1. A light-emitting section consisting of a plurality of light-emitting elements that emits light into an air passage through which dust flows, and a light-receiving section that receives light from the light-emitting section and outputs a signal according to the amount of light received. A dust detection device for a vacuum cleaner that outputs a signal from the light receiving section to a display section via a time constant circuit, and displays a display on the display section according to the magnitude of the output from the time constant circuit. 2. The dust detection device for a vacuum cleaner according to claim 1, wherein the light receiving section has a projected area equivalent to the light emitting area of the light emitting section. 3. The cross section of a part of the air passage to which the light emitting part and the light receiving part are attached is polygonal, and the surface other than the surface to which the light emitting part and the light receiving part are attached is configured to reflect light. dust detection device for vacuum cleaners. 4. The vacuum cleaner dust according to claim 1 or 2, wherein the light emitting part emits infrared rays, and the light receiving part has a filter and slit that do not allow visible light to pass through, and a condenser that collects the light. Detection device.