JP4476245B2 - Vacuum cleaner with dust detection circuit - Google Patents

Description

The present invention relates to a vacuum cleaner provided with a dust detection circuit, and more particularly, to a vacuum cleaner provided with a dust detection circuit capable of adjusting sensitivity reduction due to variations in sensitivity and dirt.

  FIG. 3 is a diagram showing a general dust detection circuit mounted on a general vacuum cleaner. In the case of a general dust detection circuit, the photocurrent of the light emitting element 112 is illustrated in order to correct the variation in the position of the light receiving element 114 and the position of the light emitting element 112 and the variation in the sensitivity of the light receiving element 114 and the sensitivity of the light emitting element 112. It was necessary to adjust with a variable resistor etc. For this reason, there is a problem that an operator spends a lot of labor in adjusting the photocurrent and a problem that many adjustment errors occur. In addition, after the use of the vacuum cleaner is started, dust adheres to the light receiving element 114 or the light emitting element 112, or the surface of those elements is damaged, so that the sensitivity of the dust sensor decreases. There was also a point. Patent Document 1 and Patent Document 2 are inventions that solve these problems.

  Patent Document 1 discloses a dust sensor unit having a light emitting element, a light receiving element, and an amplifier circuit provided facing each other in an intake air flow path of a vacuum cleaner, a power control device for an electric blower, and an inner surface of the intake air flow path. A signal from the dust sensor unit is provided with a circuit for detecting a decrease in luminance of the light emitting element due to dirt such as dust adhering to be generated and a circuit for correcting the sensitivity of the dust sensor unit to be constant based on the output of this circuit. The electric power control apparatus of the vacuum cleaner comprised so that the electric power of an electric blower may be controlled is disclosed.

  According to the invention disclosed in Patent Document 1, even if the operating point of the light receiving element moves due to a decrease in the amount of light from the light emitting element, a certain sensitivity can be obtained in the dust sensor unit.

  Patent Document 2 outputs a voltage adjustment signal corresponding to the multi-stage sensitivity of the dust sensor, inputs a voltage adjustment signal from the microcomputer for controlling the entire vacuum cleaner system, and outputs this signal as an analog voltage signal. A digital / analog conversion unit for converting to a voltage, a voltage adjustment signal from a microcomputer is input, a voltage adjustment unit for adjusting the voltage of the digital / analog conversion unit to be variable, and an output current of the voltage adjustment unit are amplified. Disclosed is an abnormality detection device for a vacuum cleaner dust sensor, including a voltage floor output to the dust sensor and a dust signal generator for outputting a dust signal corresponding to multi-stage sensitivity of the dust sensor to a microcomputer.

According to the invention disclosed in Patent Document 2, cleaning can be performed in an optimum state by detecting an abnormal operation of the dust sensor and performing appropriate control based thereon.
JP-A-2-307419 Japanese Patent Laid-Open No. 10-75921

  However, the inventions disclosed in Patent Document 1 and Patent Document 2 have a problem in that the sensitivity of the dust sensor may not be appropriately adjusted when the period of use of the vacuum cleaner is long. This is because when the vacuum cleaner is used for a long period of time, a large amount of dust adheres to the dust sensor.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a dust detection circuit capable of appropriately adjusting the sensitivity even when the vacuum cleaner is used for a long period of time. It is to provide.

In order to achieve the above object, according to one aspect of the present invention, a vacuum cleaner including a dust detection circuit is provided.
In a vacuum cleaner provided with a dust detection circuit for detecting dust passing through the passage part provided in the passage part through which dust passes by suction operation,
The dust detection circuit includes:
A light emitting element for irradiating the passage part with light ;
A light receiving element that receives light from the light emitting element irradiated to the passing portion ;
Detecting means for detecting that the light receiving element receives light from the light emitting element;
First adjusting means for adjusting the current flowing through the light receiving element ;
A second adjusting means for adjusting a current applied to the light emitting element ;
Control means for controlling the first and second adjusting means ,
The control means includes
After turning on the power of the vacuum cleaner, controlling the first and second adjusting means during a period when the passage of dust in the passage portion is stopped,
With the second adjusting means set to a current at which the light emitting element emits light with a predetermined amount of light,
Controlled and to gradually reduce the current flowing through the light receiving means by said first adjustment means and said light receiving element detects said detecting means that it has received,
The control by the first and second adjusting means is terminated, and the dust detection circuit can detect the passage of dust through the passage portion .

Also, the control unit of the cleaner with the dust detection circuit described above,
Even if the current flowing through the light receiving element is gradually decreased by the first adjusting means, if the detecting means cannot detect that the light receiving element has received light,
From the state where the light emitting element emits light with a predetermined amount of light by the second adjusting means, control to gradually increase the current to be supplied to the light emitting element,
It is desirable that the control by the first and second adjusting means is terminated in a state where the detecting means detects that the light receiving element has received light .

In addition, after the power of the vacuum cleaner is turned on, the dust passes through the passage portion when the suction operation of the vacuum cleaner starts from the time when the power to the vacuum cleaner is turned on during the period when the passage of dust is stopped in the passage portion. It is desirable to set the period until the start of the suction operation .

Further, the control means described above,
Further, the memory means only including,
And information representing the current through said light-receiving element has received to the first adjusted by adjustment means the light receiving element at the time of the detection means is detection knowledge, by the second adjustment means at the time that the detected It is preferable that information indicating current that is supplied to the adjusted light emitting element is stored in the storage unit .

Further, the control means described above uses the information stored in the storage means when the power of the vacuum cleaner is turned on again, and the current that flows to the light receiving element in the first adjustment means and the second adjustment. It is desirable to set a current to be applied to the light emitting element in the means .

  The dust detection circuit according to the present invention can appropriately adjust the sensitivity even when the vacuum cleaner is used for a long period of time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  FIG. 1 is a side view showing a use state of the vacuum cleaner in the present embodiment. In FIG. 1, the process which processes the stain | pollution | contamination adhering to flooring materials, such as a tatami mat and a carpet, with the cleaner 1 of this Embodiment is shown. The cleaner 1 includes a cleaner body 11, a flexible pipe 12 connected to the cleaner body 11, a grip portion 13, a connection pipe 14 connected to the grip portion 13, dust on the surface to be cleaned, and the like. And a suction port body 15 for suction.

  The cleaner body 11 includes a dust detection circuit 100 and a passage portion 102. The passage unit 102 is configured by a suction turbine, a motor that serves as a power for the suction turbine, and the like, and is a device that allows dust to pass between a light emitting element 112 and a light receiving element 114 described later. The dust detection circuit 100 is a circuit that detects dust. The grip 13 is provided with a power switch 16 and a suction air volume adjustment switch 17.

FIG. 2 is a circuit diagram of the dust detection circuit 100 according to the present embodiment. Referring to FIG. 2, the dust detection circuit 100 includes a microcomputer 110, a light emitting element 112, a light receiving element 114, a shaping device 116, a plurality of first resistors 118, and a plurality of second resistors 120. And a plurality of switching elements 122 and a plurality of third resistors 124. The microcomputer 110 controls the following parts. The first part is a first resistor 118. The second part is a part composed of the second resistor 120, the switching element 122, and the third resistor 124. The microcomputer 110 is also a device that detects whether or not the light receiving element 114 has received light based on the presence or absence of energization. The light emitting element 112 is an element that emits light when a current is supplied from the microcomputer 110. The light receiving element 114 is an element that is energized when receiving light. The light receiving element 114 is connected to the microcomputer 110 by a plurality of first resistors 118 connected in series to the light receiving element 114 and connected in parallel to each other. The shaping device 116 is a device that separates noise from a signal and shapes the waveform of the signal. By the processing of the shaping device 116, the dust sensor constituted by the light emitting element 112 and the light receiving element 114 can correctly notify the microcomputer 110 that the dust has passed. The plurality of first resistors 118 shown in FIG. 2 operate as an “element assembly” that adjusts the current passed through the light receiving element 114. The second resistor 120 is a resistor connected in series to the light emitting element 112, connected in parallel to each other, and grounded via the switching element 122 . The switching element 122 is connected to each of the plurality of second resistors 120 and switches a current flowing through the light emitting element 112. An assembly of elements formed by the plurality of second resistors 120 and the plurality of switching elements 122 operates so as to adjust the current flowing through the light emitting element 112.

  The microcomputer 110 includes a plurality of output terminals from “OUT1” to “OUT10” and two input terminals “IN1” and “IN2”.

  “IN1” is a terminal for inputting a signal shaped by the shaping device 116. This signal indicates that the above-described dust sensor has detected dust. “IN2” is a terminal for detecting the sensitivity of the dust sensor. From the signals input to “IN1” and “IN2”, the microcomputer 110 can detect whether or not the light receiving element 114 has received light. The microcomputer 110 detects this by the voltage applied to the light receiving element 114.

  When there is no dust, when the light receiving element 114 receives light from the light emitting element 112, a current can flow between the collector and the emitter of the light receiving element 114. Therefore, the voltage levels at “IN1” and “IN2” Becomes “LOW”. When the vacuum cleaner 1 sucks dust and the dust crosses the dust sensor, the light from the light emitting element 112 does not reach the light receiving element 114, so that no current flows between the collector and the emitter of the light receiving element 114. It becomes a state. In a state where no current flows, the voltage level at “IN1” and “IN2” is “HIGH”. In the present embodiment, the “voltage level” means a voltage range of the terminal with respect to the ground. In the present embodiment, the “voltage level” is expressed as “HIGH” or “LOW”. Each of these represents a predetermined voltage range. The former represents a voltage range having a larger absolute value than the latter. For example, when “LOW” is determined to represent a range from 1 V to 2 volts, the voltage range represented by “HIGH” is determined to represent a range such as from 3 V to 5 volts.

  “OUT1” to “OUT3” are terminals for supplying a current to the light receiving element 114. The current supplied through these terminals is supplied to the light receiving element 114, the shaping device 116, and “IN 2” through the first resistor 118.

“OUT 4” to “OUT 6” are terminals that output signals for supplying current to the light emitting element 112. Each of these terminals is connected to the base of the switching element 122. The collector terminals of the switching elements 122 are connected to a power source via the light emitting element 112 and the second resistor 120 . The emitter terminals of these switching elements 122 are grounded. Thereby, when each terminal from “OUT4” to “OUT6” flows a base current, the switching element 122 flows a current from the collector terminal to the emitter terminal . When the switching element 122 passes a current, a current is supplied to the light emitting element 112.

  “OUT7” is a terminal for outputting a signal indicating that the light is interrupted when the light from the light emitting element 112 to the light receiving element 114 is interrupted. The microcomputer 110 outputs the signal by setting the voltage level at this terminal to “HIGH”.

  “OUT8” is a terminal for outputting a signal indicating that an abnormality has occurred in at least one of the light emitting element 112 and the light receiving element 114. The microcomputer 110 outputs the signal by setting the voltage level at this terminal to “HIGH”. When the microcomputer 110 has not detected that the light receiving element 114 has received light even if the current flowing through the light receiving element 114 is below a certain threshold value and the current flowing through the light emitting element 112 is above another threshold value. Is output.

  “OUT9” is a terminal for outputting a signal indicating that dust is attached to the dust sensor during use or that the dust sensor has failed. The microcomputer 110 outputs the signal by setting the voltage level at this terminal to “HIGH”. The signal is output when the following requirements are satisfied. The requirement is that the microcomputer 110 has not detected that the light receiving element 114 has received light even if the following control is performed. The control is control performed so as to correspond to the information stored in the storage unit built in the microcomputer 110 after the power is turned on again. This control is a control for a first type flow path and a second type flow path, which will be described later.

  “OUT10” is a terminal for outputting a signal indicating that an abnormality has occurred in at least one of a first type flow path and a second type flow path, which will be described later. The microcomputer 110 outputs the signal by setting the voltage level at this terminal to “HIGH”. After the microcomputer 110 detects that the light receiving element 114 has received light, the signal is generated in the light receiving element 114 when at least one of an increase in current flowing through the light emitting element 112 and a decrease in current that can be passed through the light receiving element 114 occurs. If such a voltage remains constant, it is output.

The operation of the dust detection circuit based on the above structure will be described.
When the power is turned on, the microcomputer 110 sets the voltage level at the terminals from “OUT1” to “OUT3”. The microcomputer 110 sets the voltage level according to the information stored in the storage unit built therein. The voltage level is set before a signal for starting the suction turbine of the vacuum cleaner 1 is output from a terminal (not shown). When information representing the level of the terminal is not stored in the storage unit, the microcomputer 110 sets the voltage level at the terminals from “OUT1” to “OUT3” to “HIGH”. Thereby, when the use of the vacuum cleaner 1 is finished once and the power is turned on again for the microcomputer 110 to be used again, the microcomputer 110 corresponds to the information stored in the storage unit incorporated therein. Two types of current flow paths are controlled. The first type of flow path is a flow path through the first resistor 118. This flow path is constituted by a plurality of paths. The second type of flow path is a flow path including a second resistor 120, a switching element 122, and a third resistor 124, respectively. This flow path is also constituted by a plurality of paths.

  When the voltage level at the terminal is set, the microcomputer 110 determines whether or not the voltage level at “IN2” is “LOW”. At this time, the voltage level at “IN2” being “LOW” indicates that there is an abnormality somewhere in the dust detection circuit 100 except for the dust sensor. The voltage level at is set to “HIGH”. As a result, the microcomputer 110 generates a signal indicating that an abnormality has occurred somewhere in the portion other than the dust sensor in the dust detection circuit 100 and outputs it from “OUT8”.

  If the voltage level at "IN2" is "HIGH" when the voltage level at the terminals from "OUT1" to "OUT3" is set, the voltage level at the terminals from "OUT4" to "OUT6" is set To do.

  The microcomputer 110 sets the voltage level according to the information stored in the storage unit described above. Once the dust sensor is activated, if the dust sensor is further activated at a later date, there is usually no change in the sensitivity of the dust sensor. For this reason, since the voltage levels of “IN1” and “IN2” are both “LOW”, the passage 102 of the cleaner 1 can be activated. Not being “LOW” indicates that dust has adhered to the dust sensor in the previous use or that the dust sensor has failed. In this case, the microcomputer 110 sets the voltage level at “OUT9” to “HIGH”.

  When the information indicating the terminal level is not stored in the storage unit described above, the microcomputer 110 sets the voltage level at “OUT4” to “HIGH”. The voltage level at the terminals from “OUT5” to “OUT6” remains “LOW”. Thereby, a current flows through the light emitting element 112. Through the processing so far, the microcomputer 110 causes the first type flow path and the second type flow described above so that a current can flow through the light emitting element 112 and a current can flow through the light receiving element 114. Will control the road.

  When the voltage level at “OUT4” becomes “HIGH”, the microcomputer 110 determines whether or not the voltage level at “IN2” is “HIGH”. At this time, since the light from the light emitting element 112 is not blocked by dust, when the light emitting element 112 generates sufficient light and the light receiving element 114 has sufficient sensitivity, “IN1” and The voltage levels at “IN2” are all “LOW”.

When the light emitting element 112 does not generate sufficient light or the sensitivity of the light receiving element 114 is insufficient, and no information is stored in the storage unit described above, the voltage at “IN1” or “IN2” The level is “HIGH”. Therefore, when the voltage level at “IN2” is “HIGH”, the microcomputer 110 sets the voltage level at “OUT1” to “LOW”. Thus, since "IN1" and voltage supplied to the "IN2" is small Kunar, when the light emitting element 112 causes sufficient light, and the light receiving element 114 has a sufficiently sensitive, "IN1 ”And“ IN2 ”are“ LOW ”.

  If the voltage level at “IN2” does not become “LOW” because the sensitivity of the light receiving element 114 is insufficient, the microcomputer 110 sets the voltage level at “OUT2” to “LOW”. As a result, the current supplied to the light receiving element 114 and “IN1” and “IN2” is further reduced, so that the sensitivity of “IN1” and “IN2” is improved. At this time, when the light emitting element 112 generates sufficient light and the light receiving element 114 has sufficient sensitivity, the voltage level at “IN1” or “IN2” is “LOW”.

  If the voltage level at “IN2” does not become “LOW” because the sensitivity of the light receiving element 114 is insufficient, the microcomputer 110 sets the voltage level at “OUT3” to “LOW”. That is, in order to sequentially reduce the currents flowing through “IN1” and “IN2”, the microcomputer 110 sequentially sets the voltage levels at “OUT1”, “OUT2”, and “OUT3” to “LOW”. As a result, the current supplied to the light receiving element 114 and “IN1” and “IN2” is further reduced, so that the sensitivity of “IN1” and “IN2” is improved. At this time, when the light emitting element 112 generates sufficient light and the light receiving element 114 has sufficient sensitivity, the voltage level at “IN1” or “IN2” is “LOW”.

  With the control so far, when the light receiving element 114 can receive the light from the light emitting element 112, the microcomputer 110 can supply current to the light receiving element 114 until the microcomputer 110 detects that the light receiving element 114 has received light. Thus, the first type of flow path described above is controlled so as to decrease sequentially.

  Even if the level of the voltage at “OUT1” to the level of the voltage at “OUT3” is “LOW” because the sensitivity of the light receiving element 114 is low, the voltage level at “IN2” does not become “LOW”. The microcomputer 110 sets the voltage level at “OUT5” to “HIGH”. As a result, a current flows between the collector and emitter of the switching element 122 connected to this terminal, so that the current supplied to the light emitting element 112 increases. Since the current increases, the light generated by the light emitting element 112 increases.

  If the voltage level at “IN2” still does not become “LOW” due to insufficient sensitivity of the light receiving element 114, the microcomputer 110 changes the voltage level at “OUT6” to “HIGH”. To do. That is, in order to increase the current supplied to the light emitting element 112, the microcomputer 110 sets the voltage level at “OUT5” or “OUT6” to “HIGH”. Through the control up to this point, the microcomputer 110 causes the second type of flow path described above so that the current flowing through the light emitting element 112 sequentially increases until the microcomputer 110 itself detects that the light receiving element 114 has received light. Will be controlled.

  If the voltage level at “IN2” still does not become “LOW” due to insufficient sensitivity of the light receiving element 114, the microcomputer 110 changes the voltage level at “OUT8” to “HIGH”. To do. By this change, the microcomputer 110 generates a signal indicating that an abnormality has occurred in at least one of the light emitting element 112 and the light receiving element 114. Further, the signal is output from “OUT8”.

  If the voltage level at “IN2” becomes “LOW” before the voltage level at “OUT8” is changed to “HIGH”, the storage unit of the microcomputer 110 changes the voltage level at “IN2” to “LOW”. The information indicating the level of the terminals from “OUT1” to “OUT6” is stored. Thereafter, the microcomputer 110 controls at least one of the first-type flow path and the second-type flow path described above. As a result, at least one of an increase in current flowing through the light emitting element 112 and a decrease in current that can be passed through the light receiving element 114 occurs. In this case, if there is no abnormality in both the first type flow path and the second type flow path described above, the voltage at “IN2” corresponds to both “HIGH” and “LOW” described above. No longer. At this time, if the voltage applied to the light receiving element 114 remains constant, the microcomputer 110 changes the voltage level at “OUT10” to “HIGH”. With this change, the microcomputer 110 generates a signal indicating that an abnormality has occurred in at least one of the first type flow path and the second type flow path described above. Further, the signal is output from “OUT10”.

  Thereafter, the microcomputer 110 outputs a signal for starting the passage unit 102 of the cleaner 1 from a terminal (not shown). Thereby, when the dust passes through the dust sensor, light from the light emitting element 112 to the light receiving element 114 is blocked, so that the voltage level at “IN1” becomes “HIGH”. When the voltage level at “IN1” becomes “HIGH”, the microcomputer 110 sets the voltage level at “OUT7” to “HIGH”. Thereby, the microcomputer 110 generates a signal indicating that the light has been interrupted.

  As described above, the dust detection circuit according to the present embodiment can accurately adjust the sensitivity of the dust sensor by using a simple circuit and a microcomputer program sequence. In order to be able to detect even small dust, it is desirable that the sensitivity of the dust sensor be set as high as possible. In this case, it is because how much dust the control for cleaning is changed can be easily adjusted by processing the signal input to “IN1”. When the sensitivity of the dust sensor is accurately adjusted, dust can be detected accurately. There is no need for humans to adjust sensitivity. As a result, it is possible to provide a dust detection circuit that can adjust the sensitivity appropriately and does not require human hands to adjust the sensitivity.

  In addition, the dust detection circuit according to the present embodiment controls the first type flow path and the second type flow path during a period in which the passage of the dust is stopped. As a result, the sensitivity of the dust sensor is prevented from being inappropriately adjusted due to a malfunction. As a result, it is possible to provide a dust detection circuit that can appropriately adjust the sensitivity so as to prevent malfunction, and that does not require human intervention for adjusting the sensitivity.

  In addition, the dust detection circuit according to the present embodiment controls the first type flow path and the second type flow path after the power is turned on and before the passage of the dust is started. This makes it difficult for the user to notice that the sensitivity of the dust sensor is adjusted. Since it is difficult to notice that the sensitivity is adjusted, the possibility of frustrating the user is reduced. As a result, it is possible to provide a dust detection circuit that can reduce the possibility of causing irritation to the user, can appropriately adjust the sensitivity so as to prevent malfunction, and does not require human intervention to adjust the sensitivity.

  The dust detection circuit according to the present embodiment outputs a signal indicating that an abnormality has occurred when the following requirements are satisfied. The first requirement is a requirement that the microcomputer detects that the light receiving element has received light before the light receiving element can receive light from the light emitting element. The second requirement is that after the microcomputer detects that the light receiving element has received light, the voltage applied to the light receiving element does not exceed at least one of an increase in current flowing to the light emitting element and a decrease in current flowing through the light receiving element. The requirement to remain constant. The third requirement is that the microcomputer does not detect that the light receiving element has received light even if the current flowing through the light receiving element is equal to or less than the first threshold value and the current flowing through the light emitting element is equal to or greater than the second threshold value. It is a requirement that Thereby, the failure of the vacuum cleaner can be detected early. As a result, it is possible to provide a dust detection circuit that can detect a failure at an early stage, can appropriately adjust the sensitivity, and does not require human intervention to adjust the sensitivity.

  The dust detection circuit according to the present embodiment controls the first type flow path and the second type flow path so as to correspond to the stored information. Thereby, the sensitivity is quickly adjusted. As a result, it is possible to provide a dust detection circuit that can adjust the sensitivity quickly, can adjust the sensitivity appropriately, and does not require humans to adjust the sensitivity.

  Further, in the dust detection circuit according to the present embodiment, the current supplied to the light receiving element is adjusted after the light emitting element is energized and the microcomputer does not detect that the light receiving element has received light. This prevents power from being supplied to the light receiving element when the light receiving element cannot receive light. Since this is prevented, energy consumption is suppressed. As a result, it is possible to provide a dust detection circuit that can suppress energy consumption, can appropriately adjust the sensitivity, and does not require manpower to adjust the sensitivity.

  In addition, the dust detection circuit according to the present embodiment adjusts the current supplied to the light emitting element during a period in which the microcomputer does not detect that the light receiving element has received light even if the current that can be supplied to the light receiving element falls below the threshold. Is done. Thereby, power consumption is greatly suppressed. As a result, it is possible to provide a dust detection circuit that can largely suppress energy consumption, can appropriately adjust sensitivity, and does not require manual labor for adjusting sensitivity.

  In the case of the first modification of the present embodiment, the above-described dust sensor sensitivity adjustment processing may be performed during a period in which the passage of dust is stopped. An example of “a period in which the passage of dust is stopped” includes a case where there is an abnormality in the current flowing through the cleaner 1 or the temperature of the cleaner 1 and the passage unit 102 is stopped.

  In the second modification example of the present embodiment, the voltage levels at “OUT5” and “OUT6” are changed to “LOW” before the voltage levels from “OUT1” to “OUT3” are set to “LOW”. It may be set to “HIGH”.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a side view which shows the use condition of the vacuum cleaner which concerns on embodiment of this invention. It is a circuit diagram of a dust detection circuit according to an embodiment of the present invention. It is a figure showing the general dust detection circuit mounted in a general vacuum cleaner.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Vacuum cleaner, 11 Vacuum cleaner main body, 12 Flexible pipe, 13 Grasp part, 14 Connection pipe, 15 Suction port body, 16 Power switch, 17 Suction air volume adjustment switch, 100 Waste detection circuit, 110 Microcomputer, 102 Passing part , 112 light emitting element, 114 light receiving element, 116 shaping device, 118 first resistor, 120 second resistor, 122 switching element, 124 third resistor.

Claims (5)

In a vacuum cleaner provided with a dust detection circuit for detecting dust passing through the passage part provided in the passage part through which dust passes by suction operation,
The dust detection circuit includes:
A light emitting element for irradiating the passage part with light ;
A light receiving element that receives light from the light emitting element irradiated to the passing portion ;
Detecting means for detecting that the light receiving element receives light from the light emitting element ;
First adjusting means for adjusting the current flowing through the light receiving element;
A second adjusting means for adjusting a current applied to the light emitting element;
And control means for controlling said first contact and second adjusting means,
The control means includes
After turning on the power of the vacuum cleaner, controlling the first and second adjusting means during a period when the passage of dust in the passage portion is stopped,
With the second adjusting means set to a current at which the light emitting element emits light with a predetermined amount of light,
When the detection means detects that the light receiving element has received light by controlling the current flowing through the light receiving means to be gradually reduced by the first adjusting means ,
A vacuum cleaner comprising a dust detection circuit, wherein the control by the first and second adjusting means is terminated, and the dust detection circuit can detect the passage of dust through the passage portion . The control means includes
Even if the current flowing through the light receiving element is gradually decreased by the first adjusting means, if the detecting means cannot detect that the light receiving element has received light,
From the state where the light emitting element emits light with a predetermined amount of light by the second adjusting means, control to gradually increase the current to be supplied to the light emitting element,
2. The dust detection circuit according to claim 1, wherein the control by the first and second adjustment means is terminated in a state where the detection means detects that the light receiving element has received light. Vacuum cleaner . After the power of the vacuum cleaner is turned on , a suction operation is started in which the dust passes through the passage portion when the suction operation of the vacuum cleaner starts from the time the power is turned on to the vacuum cleaner during a period when the passage of the dust is stopped in the passage portion. A vacuum cleaner comprising the dust detection circuit according to claim 1, which is a period up to a time point . The control means includes
Further including storage means,
And information representing the current flowing before SL to the first tuned by the adjusting means and said light receiving element when the light receiving element is the detection unit that it has received is examined knowledge, the second adjustment means at the time that the detected and information representing the current supplied to regulated the light emitting element by, characterized in that to be stored in each said storage means, a vacuum cleaner including a dust detector according to claim 1 or 2. Wherein, during the re-introduction of the vacuum cleaner power, by using the information stored in the storage means, the current flowing the the light receiving element in the first adjusting means, said in the second adjusting means The vacuum cleaner provided with the dust detection circuit according to claim 4 , wherein a current flowing through the light emitting element is set .

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