JP7056506B2 - Detection device - Google Patents

Description

The present invention relates to a detection device that detects a change in capacitance or an electromagnetic field as a delayed change in a signal (electrical signal) to detect a detection target such as a human body, a liquid, a liquid amount, or a metal.

Conventionally, there is a technique of detecting a change in capacitance or an electromagnetic field as a delayed change in a signal to detect a human body, a liquid, a liquid amount, a metal, or the like to be detected. For example, in a capacitance sensor using a capacitance, the human body is detected from a change in the capacitance (for example, Patent Document 1). In addition to the human body, the capacitance sensor can also detect liquids, liquid volumes, liquid concentrations, and the like. Further, the metal sensor detects metal from a change in a magnetic field (for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2001-74497 Japanese Unexamined Patent Publication No. 2013-134227

However, conventionally, it is not possible to perform human body detection (detection of a human body or the like) using a capacitance and metal detection (detection of a metal or the like) using a magnetic field by using one detection device. Therefore, if the user wants to perform both human body detection and metal detection, it is necessary to prepare both a capacitance sensor and a metal sensor. Further, even in the capacitance sensor, the configuration is different between the sensor that only detects the human body and the liquid and the sensor that detects the liquid amount and the liquid concentration. Therefore, if it is desired to perform both human body detection and liquid volume (concentration) detection, it is necessary to prepare a capacitance sensor corresponding to each.

Furthermore, even on the side of manufacturers that produce capacitance sensors and metal sensors, if they are commercialized individually according to each need, the number of products will increase and the cost will increase.

One aspect of the present invention has been made in view of the above problems, and an object thereof is to realize a highly versatile detection device premised on a technique for detecting a change in capacitance or an electromagnetic field as a delay change in a signal. do.

In order to solve the above problems, the detection device according to one aspect of the present invention includes a human body detection unit that extracts a signal change depending on the presence or absence of a human body, a liquid detection unit that extracts a signal change depending on the amount or type of liquid, and a metal. It has at least one of the metal detection units for extracting the signal change depending on the presence or absence of the above, and a detection device main body to which the human body detection unit, the liquid detection unit, and the metal detection unit can be arbitrarily attached.

According to the above configuration, the presence or absence of a human body can be detected by attaching a human body detection unit to the detection device main body using one detection device main body, and the amount of liquid can be detected by attaching the liquid detection unit to the detection device main body. Alternatively, the type can be detected, and the presence or absence of metal can be detected by attaching a metal detection unit to the detection device main body.

This makes it possible to provide a highly versatile detection device premised on a technique for detecting a change in capacitance or an electromagnetic field as a delay change in a signal.

In the detection device according to one aspect of the present invention, the human body detection unit extracts the change in capacitance due to the approach of the human body as a signal delay change, and the liquid detection unit is electrostatic due to a difference in the amount or type of liquid. The capacitance change may be extracted as a signal delay change, and the metal detection unit may be configured to extract the magnetic field change due to the approach of the metal as a signal delay change.

According to the above configuration, the human body detection unit, the liquid detection unit, and the metal detection unit can be easily realized, and by extension, the detection device according to one aspect of the present invention can be easily realized.

In the detection device according to one aspect of the present invention, the human body detection unit includes a detection electrode for detecting a change in capacitance, a passive element for converting a change in capacitance as a delay change in a signal, and the detection. A reference potential electrode connected to a reference potential of the main body of the apparatus may be provided.

According to the above configuration, by further providing a reference potential electrode in addition to the detection electrode and the passive element, it is less likely to be affected by the capacitance formed on the back surface of the detection electrode, so that false detection is suppressed and the detection accuracy is improved. Can be planned.

In the detection device according to one aspect of the present invention, the liquid detection unit includes a detection electrode for detecting a change in capacitance, a passive element for converting a change in capacitance as a delayed change in a signal, and the detection. A reference potential electrode connected to a reference potential of the main body of the apparatus may be provided.

According to the above configuration, by further providing a reference potential electrode in addition to the detection electrode and the passive element, it is possible to improve the detection accuracy of the amount and type (concentration) of the liquid.

In the detection device according to one aspect of the present invention, the metal detection unit includes a detection coil for detecting a magnetic field change and a passive element for converting a capacitance change as a signal delay change. You can also do it.

According to the above configuration, the metal detection unit can be realized more easily.

In the detection device according to one aspect of the present invention, the detection device main body is simultaneously connected to connect at least two of the human body detection unit, the liquid detection unit, and the metal detection unit to the detection device main body at the same time. It can also be configured to include a unit.

According to the above configuration, one detection device main body can detect a plurality of detection targets at the same time.

In the detection device according to one aspect of the present invention, the detection device main body has a reference pulse generation unit that generates a reference pulse and a delay of a signal extracted by the human body detection unit, the liquid detection unit, or the metal detection unit. A delay pulse generation unit that generates a change as a delay pulse, a pulse synthesis unit that extracts the pulse time difference between the reference pulse and the delay pulse, a measurement determination unit that measures the pulse time difference to determine the presence or absence of detection, and the delay. The configuration may also include a connection terminal unit that enables insertion of the human body detection unit, the liquid detection unit, or the metal detection unit into the pulse transmission path of the pulse generation unit.

According to the above configuration, the detection device main body can be easily realized, and by extension, the detection device according to one aspect of the present invention can be easily realized.

The detection device according to one aspect of the present invention includes an offset amount adjusting unit for adjusting the offset amount of the pulse time difference caused by the parasitic capacitance near the human body detection unit, the liquid detection unit or the metal detection unit, and the steady magnetic field. It can also be.

According to the above configuration, the offset amount of the pulse time difference is adjusted by the offset amount adjusting unit, so that the detection accuracy is improved.

The detection device according to one aspect of the present invention may be configured to include a sensitivity adjustment mechanism that accepts sensitivity adjustment from the outside of the detection device main body.

According to the above configuration, the sensitivity can be arbitrarily adjusted from the outside of the detection device main body by using the sensitivity adjustment mechanism, so that the sensitivity can be adjusted according to the attached signal delay portion while using one detection device main body. Can be adjusted.

According to one aspect of the present invention, it is possible to realize a highly versatile detection device premised on a technique for detecting a change in capacitance or an electromagnetic field as a delay change in a signal.

It is a block diagram of the detection apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the state which the attachment for the human body detection is attached to the sensor main body in the said detection apparatus, and the human body which is a detection target is detected. It is a figure which shows the state which the liquid detection attachment is attached to the sensor main body, and the liquid which is a detection target is detected. It is a figure which shows the state which the metal detection attachment is attached to the sensor body, and the metal to be detected is detected. It is a figure which shows the state which the attachment for the human body detection is attached to the sensor main body, and the human body which is a detection target is detected. It is a figure which shows the signal waveform of each part in the said sensor main body when there is no detection target, and there is a case. It is a flowchart which shows the procedure of the offset amount adjustment and determination in the said detection apparatus, and shows the procedure which the offset amount adjustment is performed automatically at the time of power-on. It is a flowchart which shows the procedure of the offset amount adjustment and determination in the said detection apparatus, and shows the procedure when the offset adjustment button is pressed and the offset amount is adjusted. (A) is a perspective view of the front side of the sensor body, and (b) is a perspective view of the back side of the sensor body. (A) is a perspective view of the detection device having a metal detection attachment attached to the sensor body, and (b) is a perspective view of the detection device having a human body detection attachment attached to the sensor body. c) is a perspective view of the detection device in which the liquid detection attachment is attached to the sensor body. (A) is a perspective view of the detection device before attaching the metal detection attachment to the sensor body, and (b) is a perspective view of the detection device before attaching the human body detection attachment to the sensor body. , (C) is a perspective view of the detection device before attaching the liquid detection attachment to the sensor body. It is a block diagram of the detection apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the signal waveform of each part in the sensor main body in the case of the detection device of FIG. 12, the case where there is no detection target, the case where there is a detection target but the influence is small, and the case where there is a detection target and the influence is large. It is a block diagram of the detection apparatus which concerns on Embodiment 3 of this invention. (A) is a perspective view of the front side of the sensor main body of the detection device shown in FIG. 14, and (b) is a perspective view of the back side of the sensor main body. (A) is a perspective view of a beverage maker equipped with the detection device shown in FIG. 14, and (b) is a perspective view and a partially enlarged view of a state in which the sensor body is removed from the beverage maker. (A) is a perspective view of the non-contact power feeding device equipped with the detection device shown in FIG. 14 as viewed from above, and (b) is a perspective view of the non-contact power feeding device as viewed from below.

Hereinafter, embodiments relating to one aspect of the present disclosure (hereinafter, also referred to as “the present embodiment”) will be described with reference to the drawings.

§1 Application example First, about an example of the detection device 1 using FIGS. 1, 9 (a) and 9 (a) and 9 (b), 10 (a) to (c), and 11 (a) to 11 (c). explain. The detection device 1 is a human body detection signal delay unit (human body detection unit) 15A, 15D that extracts a signal change depending on the presence or absence of a human body (detection target), and a liquid detection that extracts a signal change depending on the amount or type of liquid (detection target). At least one of the signal delay unit (liquid detection unit) 15B for metal detection and the signal delay unit (metal detection unit) 15C for metal detection that extracts signal changes depending on the presence or absence of metal (detection target), and a plurality of these signal delay units. It has a sensor body (detection device body) 20 to which 15A to 15D can be arbitrarily mounted.

The human body detection signal delay unit 15A is provided on the human body detection attachment 10A, and the human body detection signal delay unit 15D is provided on the human body detection attachment 10D. Further, the liquid detection signal delay unit 15B is provided on the liquid detection attachment 10B, and the metal detection signal delay unit 15C is provided on the metal detection attachment 10C.

In the present embodiment, the sensor main body 20 has a rectangular box shape, has a detection indicator lamp 27 on the front surface side, and has a main body side connection terminal portion 45 for connecting to the detection attachment 10 on the back surface side.

In the following, unless it is necessary to distinguish between the attachments 10A to 10D, they are collectively referred to as the detection attachment 10. Similarly, each signal delay unit 15A to 15D is also collectively referred to as a signal delay unit 15 unless it is necessary to distinguish them.

The detection attachment 10 is provided with an accommodating portion 11 for accommodating the sensor main body 20, and the accommodating portion 11 is provided with a component-side connection terminal portion 12 for connecting to the sensor main body 20.

With the metal detection attachment 10C attached, by holding the detection coil 15C1 over foodstuffs and the like, if metal foreign matter is mixed in, it can be detected. Further, in the state where the attachments 10A and 10D for detecting the human body are attached, by placing the food material on the detection electrode 15A1, it is possible to detect when the pet approaches the food material or the child reaches out. The human body detection attachment 10D has higher detection accuracy than the human body detection attachment 10A. With the liquid detection attachment 10B attached, by setting the PET bottle 13 in the holder 14, it is possible to detect foreign matter contamination due to an abnormal concentration of the liquid inside the PET bottle 13.

In this way, in the detection device 1, by exchanging the detection attachment 10 attached to the sensor main body 20, it is possible to perform human body detection, liquid volume detection (concentration detection), and metal detection with one device. ..

§2 Configuration example [Embodiment 1]
In the present embodiment, FIGS. 1 to 6 are used to illustrate a detection device 1 capable of detecting a human body, a liquid amount, and a metal as one aspect of the detection device of the present disclosure.

(Configuration of detection device 1)
The configuration of the detection device 1 according to one aspect of the present disclosure will be described. FIG. 1 is a block diagram of the detection device 1. As shown in FIG. 1, the detection device 1 has a sensor body (detection device body) 20 to which signal delay units 15A to 15D can be arbitrarily mounted. In other words, it has a sensor body (detection device body) 20 to which the detection attachments 10A to 10D can be arbitrarily attached. In the present embodiment, as the detection attachment 10, the human body detection attachments 10A and 10D, the liquid detection attachment 10B, and the metal detection attachment 10C can be attached.

(Structure of sensor body 20)
The sensor main body 20 includes a reference pulse generation unit 21, a delay pulse generation unit 22, a pulse synthesis unit 23 microprocessor 24, an offset adjustment button 25, a sensitivity operation knob 26, a detection indicator lamp 27, and the like.

The reference pulse generation unit 21 includes a Schmidt inverter 211, a capacitor 212, and a resistance 213, and generates a reference pulse according to a specified pulse. The reference pulse generation unit 21 generates a reference pulse that can be appropriately combined with the delay pulse generated by the delay pulse generation unit 22. The adjustment of the reference pulse is performed by the capacitor 212 and the resistance 213. The generated reference pulse is output to the pulse synthesis unit 23 via the buffers 214 and 215.

The delay pulse generation unit 22 has a buffer 221, a NOT circuit 222, a first connection terminal T1-a, a second connection terminal T1-b, and a third connection terminal T1-c, and receives a delay signal from the detection attachment 10. Convert to a delayed pulse. The signal delay unit 15 of the detection attachment 10 is inserted into the pulse transmission path of the delay pulse generation unit 22, and the delay pulse generation unit 22 has a first connection terminal T1-a and a second connection terminal T1- that enable the insertion. b, a third connection terminal T1-c is provided.

A reference pulse is input to the buffer 221 from the reference pulse generation unit 21. The first connection terminal T1-a is connected to the output side of the buffer 221. The first connection terminal T2-a, which will be described later, of the detection attachment 10 is connected to the first connection terminal T1-a.

A second connection terminal T1-b is connected to the input side of the NOT circuit 222. By connecting the second connection terminal T2-b of the detection attachment 10, which will be described later, to the second connection terminal T1-b, a delay signal delayed due to the detection target is input from the detection attachment 10. .. The delay signal is converted into a pulse signal by the NOT circuit 222 and inverted. The output side of the NOT circuit 222 is connected to the pulse synthesis unit 23, and the delayed pulse, which is an inverted pulse signal, is output to the pulse synthesis unit 23.

The third connection terminal T1-c is connected to the reference potential. A third connection terminal T2-c, which will be described later, of the detection attachment 10 is connected to the third connection terminal T1-c. The third connection terminal T2-c is provided on the liquid detection attachment 10B, the metal detection attachment 10C, and the human body detection attachment 10D.

The first connection terminal T1-a, the second connection terminal T1-b, and the third connection terminal T1-c provided in the delay pulse generation unit 22 are the main body side connection terminal portion 45 (FIG. 9) of the sensor main body 20 described above. See).

The pulse synthesis unit 23 has an AND circuit 231 and synthesizes a reference pulse input from the reference pulse generation unit 21 and a delay pulse input from the delay pulse generation unit 22, and extracts the combined pulse. The combined pulse is a pulse signal having a time width from the rise of the reference pulse to the rise of the delayed pulse. The extracted combined pulse is output to the delay time measuring unit 243 described later in the microprocessor 24. A synthetic pulse having a time width from the falling edge of the reference pulse to the falling edge of the delayed pulse may be extracted.

The microprocessor (measurement determination unit) 24 includes an offset amount adjustment unit 241, a sensitivity adjustment unit 242, a delay time measurement unit 243, a determination unit 244, and an output unit 245.

The offset amount adjusting unit 241 adjusts the pulse time difference included in the delayed signal generated by the parasitic capacitance and the steady magnetic field existing in the vicinity of the signal delay unit 15 described later. The offset amount adjusting unit 241 automatically adjusts the offset amount when the power of the sensor main body 20 is turned on. The offset amount is also adjusted when the offset adjustment button 25 is pressed.

The sensitivity adjustment unit 242 is a predetermined value (threshold value) used for determination when the determination unit 244 determines the presence / absence of detection (presence / absence of detection of the detection target) based on the pulse width of the combined pulse output from the pulse synthesis unit 23. ) Is adjusted. The sensitivity is adjusted by using the sensitivity operation knob 26. As a result, the user can easily adjust the sensitivity according to the attached signal delay unit 15 while using one sensor main body 20. The impression operation knob 26 and the sensitivity adjusting unit 242 form a sensitivity adjusting mechanism that accepts the adjustment of the sensitivity from the outside of the sensor main body 20.

The delay time measuring unit 243 measures the pulse width of the combined pulse input from the pulse combining unit 23. When the measured pulse width exceeds a predetermined value (threshold value), the determination unit 244 determines that the detection target corresponding to the detection attachment 10 is detected. When it is determined that the detection is present, the output unit 245 supplies a current to the detection indicator lamp 27, and the detection indicator lamp 27 lights up.

The detection attachment 10 is configured to be detachable and attachable to the sensor body 20. The human body detection signal delay units 15A and 15D provided on the human body detection attachments 10A and 10D extract the change in capacitance due to the approach of the human body as the signal delay change. The liquid detection signal delay unit 15B provided in the liquid detection attachment 10B extracts a change in capacitance due to a difference in the amount or type of liquid as a signal delay change. The metal detection signal delay unit 15C provided in the metal detection attachment 10C extracts the magnetic field change due to the approach of the metal as the signal delay change.

The signal delay unit 15 has a first connection terminal T2-a, a second connection terminal T2-b, and a third connection terminal T2-c. The first connection terminal T2-a is connected to the first connection terminal T1-a of the delay pulse generation unit 22 of the sensor body 20, the second connection terminal T2-b is connected to the second connection terminal T1-b, and the second connection terminal T2-b is connected. The 3 connection terminal T2-c is connected to the 3rd connection terminal T1-c. The first connection terminal T2-a, the second connection terminal T2-b, and the third connection terminal T2-c constitute the component-side connection terminal portion 12 (see FIG. 11) described above.

Hereinafter, the attachments 10A and 10D for detecting a human body, the attachment 10B for liquid detection, and the attachment 10C for metal detection will be described with reference to FIGS. 2 to 5.

(Attachment for human body detection 10A)
FIG. 2 is a diagram showing a state in which the human body detection attachment 10A is attached to the sensor main body 20 and the human body 900 to be detected is detected. As shown in FIG. 2, the human body detection attachment (first signal delay unit) 10A includes a signal delay unit 15A. The signal delay unit 15A includes a detection electrode 15A1 and a resistance 15A2.

The detection electrode 15A1 is a flat plate formed of a conductor such as metal, and forms a human body capacitance CX together with the human body 900 when the human body 900 having the same potential as the ground approaches. The human body 900 is an example of a conductor having the same potential as the earth. The detection electrode 15A1 is connected to the first connection terminal T2-a via the resistor 15A2, and the detection electrode 15A1 and the resistor 15A2 are connected to the second connection terminal T2-b.

The sensor body 20 detects a change in the capacitance CZ at the input of the sensor body 20. The capacitance CZ changes when the capacitance between the detection electrode 15A1 and the ground changes as the human body 900 approaches the detection electrode 15A1. In addition, the capacitance CZ includes a parasitic capacitance between the detection electrode 15A1 and various conductors arranged around the detection electrode 15A1. The capacitance CZ has, as parasitic capacitance, the capacitance Cll between the detection electrode 15A1 and the ground, the capacitance C12 between the reference potential (circuit GND) of the sensor body 20 and the ground, and the reference potential (wiring and the sensor body 20). Includes a capacitance C2 with and from the circuit GND).

The capacitance CZ at the input of the sensor body 20 when the human body 900 does not approach the detection electrode 15A1 (without the human body capacitance CX) is
CZ ＝ C11 ＋ C2 × C12 / (C2 ＋ C12) ・ ・ ・ (1)
Indicated by.

Further, the capacitance CZ at the input of the sensor body 20 when the human body 900 approaches the detection electrode 15A1 (with the human body capacitance CX) is
CZ ＝ CX ＋ C11 ＋ C2 × C12 / (C2 ＋ C12) ・ ・ ・ (2)
Indicated by.

The time constant:
A response waveform of CZ × R11 is obtained, and the obtained response waveform is given to the sensor main body 20. The resistance value R11 of the resistor 15A2 is adjusted so that the response waveform given to the sensor main body 20 becomes a response waveform suitable for the sensor main body 20.

(Attachment for liquid detection 10B)
FIG. 3 is a diagram showing a state in which the liquid detection attachment 10B is attached to the sensor main body 20 and the liquid 901 to be detected is detected. As shown in FIG. 3, the liquid detection attachment (first signal delay unit) 10B includes a signal delay unit 15B. The signal delay unit 15B includes a detection electrode 15B1, a ground electrode 15B2, and a resistor 15B3.

The detection electrode 15B1 is a flat plate formed of a conductor such as metal, and is installed in the height direction of a container for containing the liquid 901. The detection electrode 15B1 is connected to the first connection terminal T2-a via the resistor 15B3, and the detection electrode 15B1 and the resistor 15B3 are connected to the second connection terminal T2-b.

The ground electrode 15B2 is a flat plate formed of a conductor such as metal, and is arranged so as to form a right angle with the detection electrode 15B1 on the bottom surface where a container for containing a liquid is set. The ground electrode 15B2 is connected to the third connection terminal T2-c. When the container containing the liquid 901 is set, a liquid capacity CX2 corresponding to the amount of the liquid 901 is formed between the detection electrode 15B1 and the ground electrode 15B2.

The sensor body 20 detects a change in the capacitance CZ at the input of the sensor body 20. The capacitance CZ is a synthetic capacitance including a liquid capacitance CX2 according to the amount of liquid and a parasitic capacitance CP1 between the detection electrode 15B1 and the ground electrode 15B2.

The capacity CZ at the input of the sensor body 20 when the liquid 901 is set (with the liquid capacity CX2) is
CZ ＝ CX2 ＋ CP1 ・ ・ ・ (3)
Indicated by.

Since the liquid 901 has a larger dielectric constant than the air, as the amount of the liquid 901 between the detection electrode 15B1 and the ground electrode 15B2 increases, the liquid capacity CX2 also increases.

A response waveform having a time constant of CZ × R12 is obtained by the resistance value R12 of the resistor 15B3 built in the signal delay unit 15B and the capacitance CZ that changes according to the amount of the liquid 901, and the obtained response waveform is a sensor. It is given to the main body 20. The resistance value R12 of the resistor 15B3 is adjusted so that the response waveform given to the sensor main body 20 becomes a response waveform suitable for the sensor main body 20.

(Attachment for metal detection 10C)
FIG. 4 is a diagram showing a state in which the metal detection attachment 10C is attached to the sensor main body 20 and the metal 902 to be detected is detected. As shown in FIG. 4, the metal detection attachment (second signal delay unit) 10C includes a signal delay unit 15C. The signal delay unit 15C includes a detection coil 15C1 and a resistance 15C2. The detection coil 15C1 may be a winding wound with an electric wire or a pattern coil printed on a substrate.

One end of the detection coil 15C1 is connected to the first connection terminal T2-a, and the other end of the detection coil 15C1 is connected to the second connection terminal T2-b. The other end of the detection coil 15C1 and the second connection terminal T2-b are connected to the third connection terminal T2-c via the resistor 15C2.

When the metal 902 approaches the detection coil 15C1, mutual inductance is formed. The inductance L1 of the detection coil 15C1 changes due to the formation of the mutual inductance.

A response waveform having a time constant of L1 × R13 is obtained by the resistance value R13 of the resistor 15C2 built in the signal delay unit 15C and the inductance L1 changed by the proximity of the metal 902, and the obtained response waveform is a sensor. It is given to the main body 20. The resistance value R13 of the resistor 15C2 is adjusted so that the response waveform given to the sensor main body 20 becomes a response waveform suitable for the sensor main body 20.

That is, in the detection attachment 10, even if the capacitance CZ and the inductance L1 are different due to the difference in the detection target, each of them is built in the signal delay unit 15 so that the response waveform (change amount) given to the sensor main body 20 is uniform. The resistance value of the resistance is adjusted. That is, these resistances built in the signal delay unit 15 correspond to a change amount adjusting unit in which each of the plurality of signal delay units 15 aligns the change amount of the delay change of the signal given to the sensor main body 20.

(Attachment for human body detection 10D)
In the configuration of the attachment 10A for human body detection shown in FIG. 2, the capacitance CZ also detects the stray capacitance and the change on the back surface of the electrode 15A1. The formula for obtaining the capacitance CZ is the same as the above formula (2). Therefore, when the distance between the back surface of the electrode 15A1 and the ground fluctuates, the capacitance CZ fluctuates.

There is no problem when the fluctuation range of the capacitance CZ is small, but when the fluctuation range is large and the response waveform of the time constant CZ × R11 fluctuates as much as when the human body 900 approaches the electrode 15A1, the pulse width of the combined pulse S6 is predetermined. The value (threshold value) is exceeded. As a result, it is erroneously determined that the delay time measuring unit 243 is in the detection state of detecting the detection target.

The attachment 10D for human body detection shown in FIG. 5 has a ground electrode 15D2 in order to eliminate such an erroneous determination due to detecting the stray capacitance and change on the back surface of the electrode 15A1. The human body detection attachment 10D can be provided in place of the human body detection attachment 10A (or as a fourth detection attachment 10).

FIG. 5 is a diagram showing a state in which the human body detection attachment 10D is attached to the sensor main body 20 to detect the human body 900 to be detected. As shown in FIG. 5, the human body detection attachment 10D includes a signal delay unit 15D. The signal delay unit 15D includes a detection electrode 15D1, a ground electrode 15D2, and a resistor 15D3.

The detection electrode 15D1 is a flat plate formed of a conductor such as metal, and when the human body 900 having the same potential as the ground approaches, the human body capacity CX1 is formed together with the human body 900 on the surface to which the human body 900 approaches. The detection electrode 15D1 is connected to the first connection terminal T2-a via the resistor 15D3, and the detection electrode 15D1 and the resistor 15D3 are connected to the second connection terminal T2-b.

The ground electrode 15D2 is a flat plate formed of a conductor such as metal arranged so as to face the detection electrode 15D1. The ground electrode 15D2 is connected to the third connection terminal T2-c.

The sensor body 20 detects a change in the capacitance CZ at the input of the sensor body 20. The capacitance CZ changes when the capacitance between the detection electrode 15D1 and the ground changes as the human body 900 approaches the detection electrode 15D1. Further, the capacitance CZ includes a capacitance between the detection electrode 15D1 and the ground electrode 15D2, and a parasitic capacitance between various conductors arranged around the detection electrode 15D1 and the ground electrode 15D2. The capacitance CZ is the capacitance CP between the detection electrode 15D1 and the ground electrode 15D2, the capacitance Cll between the ground electrode 15D2 and the ground as the parasitic capacitance, and the reference potential (circuit GND) of the sensor body 20 and the ground. Includes a capacitance C12 between and a capacitance C2 between the wiring and the reference potential (circuit GND) of the sensor body 20.

The capacitance CZ at the input of the sensor body 20 when the human body 900 does not approach the detection electrode 15D1 (without the human body capacitance CX1) is
CZ ＝ (CP2 ＋ C2) × (C11 ＋ C12) / (CP2 ＋ C2 ＋ C11 ＋ C12) ・ ・ ・ (4)
Indicated by.

Further, when the human body 900 approaches the detection electrode 15D1 (with the human body capacity CX1), the capacity CZ at the input of the sensor body 20 on the surface side of the detection electrode 15D1 is
CZ ＝ CX1 ＋ {(CP2 ＋ C2) × (C11 ＋ C12) / (CP2 ＋ C2 ＋ C11 ＋ C12)} ・ ・ ・ (5)
Indicated by.

Further, when the detection electrode 15D1 and the ground electrode 15D2 move and the capacitance between the ground electrode 15D2 and the ground fluctuates from Cll to CX3, the capacitance CZ at the input of the sensor main body 20 is determined.
CZ ＝ (CP2 ＋ C2) × {(C12 ＋ CX3) / (CP2 ＋ C2 ＋ C12 ＋ CX3)} ・ ・ ・ (6)
Indicated by.

As shown in the formula (6), even if the capacitance CX3 between the ground electrode 15D2 and the ground fluctuates, the capacitance CZ does not become larger than the capacitance CP between the detection electrode 15D1 and the ground electrode 15D2. ..

Therefore, even if an unintended change in capacitance occurs on the ground electrode 15D2 side, the response waveform of the time constant CZ × R14 is suppressed from fluctuating as much as when the human body 900 approaches the detection electrode 15D1, and the microprocessor is used. It is possible to suppress the erroneous determination by 24.

(Signal waveform of each part of the sensor body 20)
Next, with reference to FIG. 6, the signal waveform of each part in the sensor main body 20 will be described when there is no detection target and when there is no detection target. FIG. 6 is a diagram showing signal waveforms of each part in the sensor main body 20 when there is no detection target and when there is no detection target. S1 to S6 in FIG. 6 correspond to the signal waveforms of the respective parts marked with S1 to S6 in FIG.

As shown in FIG. 6, the signals S1 and S5 output from the buffers 214 and 215 of the reference pulse generation unit 21 and the signal S2 output from the buffer 221 of the delay pulse generation unit 22 and sent to the signal delay unit 15 are , Both are reference pulses.

S3 is a delay signal output from the signal delay unit 15 and input to the NOT circuit 222 of the delay pulse generation unit 22. In the delay signal S3, the rising edge of the pulse and the falling edge of the pulse are slightly blunted even in the absence of the human body 900, the liquid 901, and the metal 902 to be detected. This is because the pulse time difference occurs due to the parasitic capacitance and the steady magnetic field existing in the vicinity of the signal delay portion 15.

When the human body 900, the liquid 901, and the metal 902, which are the detection targets, are present in the delay signal S3, the number of time points in the signal delay unit 15 becomes large, and the rising edge of the pulse and the falling edge of the pulse are greatly blunted (largely delayed).

S4 is a delayed pulse in which the delay signal S3 is returned to the pulse waveform again by the NOT circuit 222 of the delay pulse generation unit 22 and inverted. When the detection target exists, the delay pulse S4 is delayed by a time width t1 with respect to the reference pulse. The delayed pulse S4 is delayed by the time width t0 due to the pulse time difference even when the detection target does not exist, but the time point t0 is sufficiently shorter than the time width t1.

S6 is a composite pulse in which the reference pulse S5 and the delay pulse S4 are combined by the AND circuit 231 of the pulse synthesis unit 23. The combined pulse S6 is a pulse signal having a time width (t1) from the rising edge of the reference pulse S5 to the rising edge of the delayed pulse S4.

The synthetic pulse S6 is input to the microprocessor 24. The offset amount adjusting unit 241 adjusts the input combined pulse S6, and the delay of the time width t0 is removed. The delay time measuring unit 243 measures the pulse time width (pulse width) in the combined pulse S6, and when the time width exceeds a preset predetermined value (threshold value), the determination unit 244 detects a detection target. It is determined that the detection status is high. The predetermined value (threshold value) used by the determination unit 244 for determination can be adjusted by the sensitivity adjustment unit 242 as described above.

(Explanation of offset amount adjustment and judgment procedure)
7 and 8 are flowcharts showing the procedure of adjusting and determining the offset amount. FIG. 7 shows a procedure in which the offset amount is automatically adjusted when the power is turned on, and FIG. 8 shows a procedure in which the offset adjustment button 25 is pressed to adjust the offset amount.

As shown in FIG. 7, when the power of the detection device 1 (sensor body 20) is turned on, the offset amount adjusting unit 241 measures the delay time Tx (time width t0 in FIG. 6) of the detection attachment 10 N times. (Step 1), and the average value is calculated as the offset amount ΔT (step 2). After that, the determination unit 244 acquires the threshold value (threshold value) Tth used for the determination (step 3), and the delay time measurement unit 243 measures the delay time Tx (time width t0, t1 in FIG. 6) (step 4). .. The determination unit 244 determines whether or not the value obtained by subtracting the offset amount ΔT from the delay time Tx is larger than the threshold value (threshold value) Tth (step 5), and if it is large, “detection” (step 6). If it is not large, it is determined as "not detected" (step 7), and the process returns to step 3.

As shown in FIG. 8, when the power of the detection device 1 (sensor main body 20) is turned on, the determination unit 244 acquires the threshold value Tth used for the determination (step 11). The offset amount adjusting unit 241 determines whether or not the offset adjusting button 25 is pressed (step 12). If it is not pressed, the process proceeds to step S13, the same steps 13 to 16 as in steps 4 to 7 in the flowchart of FIG. 7 are executed, and the process returns to step 11. On the other hand, if it is pressed, the process proceeds to step S17, the same steps 17 and 18 as steps 1 and 2 in the flowchart of FIG. 7 are executed, and the process proceeds to step 13.

(Appearance and usage example of detection device 1)
Next, the appearance of the detection device 1 and usage examples will be described with reference to FIGS. 9A and 9B, FIGS. 10A to 10C, and FIGS. 11A and 11C. .. 9A is a perspective view of the front side of the sensor main body 20 of the detection device 1, and FIG. 9B is a perspective view of the back side of the sensor main body 20.

FIG. 10A is a perspective view of the detection device 1 in which the metal detection attachment 10C is attached to the sensor body 20, and FIG. 10B is a perspective view of the detection device 1 in which the human body detection attachment 10A is attached to the sensor body 20. FIG. 3C is a perspective view of a detection device in which a liquid detection attachment 10B is attached to a sensor body 20.

11A is a perspective view of the detection device 1 before attaching the metal detection attachment 10C to the sensor body 20, and FIG. 11B is a detection device 1 before attaching the human body detection attachment 10A to the sensor body 20. (C) is a perspective view of the detection device 1 before attaching the liquid detection attachment 10B to the sensor main body 20.

As shown in FIG. 9A, the sensor main body 20 has a power button 41, an offset adjustment button 25, a detachable button 42, a sensitivity adjustment knob 26, a detection indicator lamp 27, a power ON / OFF lamp 43, etc. on the front surface side. A charging adapter 44 or the like to which the charger 60 is connected is provided on the side surface. Further, as shown in FIG. 9B, the sensor main body 20 has a main body side connection terminal portion 45 for connecting to the detection attachment 10 on the back surface side.

The attachment / detachment button 42 protects the circuit of the sensor body 20 by pressing the attachment / detachment button 42 from the sensor body 20 when the detection attachment 10 is attached / detached. A battery may be built in instead of the charging adapter 44.

As an example of the use of the detection device 1, in the case of a general household, for example, in the state where the metal detection attachment 10C shown in FIG. If it is mixed, this can be detected. Further, in the state where the attachment 10A for detecting the human body shown in FIG. 10B is attached, the food material is placed on the detection electrode 15A1 to detect when the pet approaches the food material or the child reaches out. can do. By attaching the human body detection attachment 10D instead of the human body detection attachment 10A, erroneous detection can be suppressed and the detection accuracy can be improved. Further, in the state where the liquid detection attachment 10B of FIG. 10C is attached, the PET bottle 13 is set in the holder 14 provided with the detection electrode 15B1 and the ground electrode 15B2, thereby concentrating the liquid inside the PET bottle 13. It is possible to detect foreign matter contamination due to an abnormality.

As an example of using the detection device 1, in the case of general security at an airport, a station, a stadium, etc., for example, in the state where the metal detection attachment 10C of FIG. 10A is attached, the detection coil 15C1 is attached to foodstuffs or the like. By holding it over, it can be detected if you carry a gun sword or the like. Further, in the state where the attachment 10A for detecting the human body shown in FIG. 10B is attached, it is possible to detect an organism that is about to be illegally brought in. Also in this case, by attaching the human body detection attachment 10D instead of the human body detection attachment 10A, erroneous detection can be suppressed and the detection accuracy can be improved. Further, in the state where the liquid detection attachment 10B of FIG. 10C is attached, it is possible to detect an abnormality in the concentration of the liquid inside the PET bottle 13.

[Embodiment 2]
In the present embodiment, the detection device 2 provided with the sensor main body 30 instead of the sensor main body 20 will be described. For convenience of explanation, the same reference numerals are given to the members having the same functions as the members described in the above-described embodiment, and the description thereof will not be repeated.

FIG. 12 is a block diagram of the detection device 2. As shown in FIG. 12, the detection device 2 includes a sensor main body 30 instead of the sensor main body 20. The sensor main body 30 includes a reference pulse generation unit 31 instead of the reference pulse generation unit 21, and replaces the microprocessor 24 with a time-voltage conversion unit 32, a waveform smoothing unit 33, a voltage determination unit 34, and an output unit 35. To prepare for. The output unit 35 is provided with a light emitting diode 352 corresponding to the detection indicator lamp 27 described above.

The reference pulse generation unit 31 is different from the reference pulse generation unit 21 in that an offset adjustment unit 311 is provided between the buffer 214 and the buffer 215. The offset adjusting unit 311 includes a variable resistor 312 and a capacitor 313, and adjusts the offset amount so that the above-mentioned pulse time difference caused by the parasitic capacitance near the signal delay unit 15 and the steady magnetic field does not occur.

FIG. 13 is a diagram showing signal waveforms of each part in the sensor main body 30 when there is no detection target, when there is a detection target but the influence is small, and when there is a detection target and the influence is large. S1 to S6 in FIG. 13 correspond to the signal waveforms of the parts with S1 to S6 in FIG. 12, and V1 to V3 in FIG. 13 correspond to the voltages of the parts with V1 to V3 in FIG.

As shown in FIG. 13, by adjusting the offset amount, the phase delay of the reference pulse S5 output from the buffer 215 is adjusted, and the combined pulse S6 does not include the pulse having the time width t0.

The time-voltage conversion unit 32 includes a NOT circuit 321, a resistor 322, a transistor 323, a constant current source 324, and a variable capacitor 325. The time-voltage conversion unit 32 outputs a voltage corresponding to the time of the pulse width of the combined pulse S6 given by the pulse combining unit 23.

The NOT circuit 321 inverts the combined pulse S6 and outputs it. The inverted combined pulse is output to the base of the transistor 323 via the resistor 322. The transistor 323 is turned off during the period when the inverted combined pulse is low, during which the current flows from the constant current source 324 to the variable capacitor 325 and charges are accumulated.

As shown in FIG. 13, the voltage obtained from the electric charge stored in the variable capacitor 325 rises from V1 in proportion to time. Since the current is constant, the slope of the voltage rise can be adjusted by changing the capacity of the variable capacitor 325. When the transistor 323 is turned on, the voltage corresponding to the electric charge stored in the variable capacitor 325 is momentarily held.

The waveform smoothing unit 33 includes a diode 331, a resistance 332, and a capacitor 333, smoothes the voltage corresponding to the electric charge stored in the variable capacitor 325, and outputs the voltage V2 to the voltage determination unit 34.

The voltage determination unit 34 includes a comparator 341 and a variable power supply 342, and when the voltage V2 exceeds the voltage V3 of the variable power supply 342, the light emitting diode (indicator) 352 provided in the output unit 35 lights up. The output unit 35 includes a resistor 351 and a light emitting diode 352, and the output unit 35 is adjusted so that a current flows through the light emitting diode 352 when the voltage V2 exceeds the voltage V3.

In such a configuration, the sensitivity for determining that the detection target is detected can be adjusted by changing either the capacity of the variable capacitor 325 or the voltage V3 of the variable power supply 342. Although not shown, the variable capacitor 325 and the variable power supply 342 are connected to the sensitivity operation knob 26 (see FIG. 1) provided outside the sensor main body 30, and the variable capacitor 325, the variable power supply 342, and the sensitivity operation knob are connected. At 26, a sensitivity adjusting mechanism is configured.

Such a sensor main body 30 can be configured to be cheaper than the sensor main body 20 because the microprocessor 24 is not used.

[Embodiment 3]
In this embodiment, the detection device 3 provided with the sensor main body 40 instead of the sensor main body 20 will be described. For convenience of explanation, the same reference numerals are given to the members having the same functions as the members described in the above-described embodiment, and the description thereof will not be repeated.

FIG. 14 is a block diagram of the detection device 3. As shown in FIG. 14, the detection device 3 includes a sensor main body 40 instead of the sensor main body 20. The sensor main body 20 includes a main body side connection terminal portion 45, but the sensor main body 40 includes a main body side connection terminal portion (simultaneous connection portion) 46. The main body side connection terminal portion 46 is configured to include a plurality of main body side connection terminal portions 45, and a plurality of detection attachments 10 can be simultaneously connected to the sensor main body 40.

FIG. 15A is a perspective view of the front side of the sensor main body 40 of the detection device 3, and FIG. 15B is a perspective view of the back side of the sensor main body 40. As shown in FIG. 15A, the appearance of the front surface side is the same as that of the sensor main body 20 (see FIG. 9A), but as shown in FIG. 15B, the back surface side has the same appearance. It is provided with three main body side connection terminal portions 45.

With such a configuration, when the signal delay due to the detection target occurs in any one of the plurality of connected signal delay units 15, the sensor main body 40 detects this as a delay change, and the detection indicator lamp. 27 is turned on to notify the user. That is, using one sensor body 40, for example, human body detection, liquid volume detection, and metal detection can be performed.

(Usage example of detection device 3)
Next, an example of using the detection device 3 will be described with reference to FIGS. 16A and 16B. FIG. 16A is a perspective view of a beverage maker 70 equipped with a detection device 3, and FIG. 16B is a perspective view and a partially enlarged view of a state in which the sensor main body 40 is removed from the beverage maker 70.

As shown in FIGS. 16A and 16B, the detection device 3 is mounted on a beverage maker 70 such as coffee. It has a detection electrode 71 for human body detection (signal delay units 15A and 15D), a detection electrode 74 for liquid detection and a ground electrode 73 (signal delay unit 15B), and a detection coil 76 for metal detection (signal delay unit 15C). The detection electrode 71, the detection electrode 74, the ground electrode 73, and the detection coil 76 are connected to the sensor main body 40 via a plurality of main body side connection terminal portions 45 provided corresponding to each.

The detection coil 76 for metal detection is provided in the nozzle 79, which is a flow path for beverages. As a result, if a knife or the like for grinding coffee beans is chipped and mixed in the beverage, it can be detected.

The detection electrode 71 for detecting a human body is provided as a large flat plate electrode on a mounting table on which a cup 78 or the like is placed. As a result, even if the cup 78 is not touched, it can be detected only by a hand invading the periphery of the mounting table, and burns and the like can be prevented.

The detection electrode 74 for the liquid detection unit is provided at the back of the mounting table, and the ground electrode 73 is provided at the mounting surface of the mounting table. This makes it possible to prevent the beverage from overflowing when the supply button is accidentally pressed twice.

The control unit (not shown) of the beverage maker 70 stops the supply of beverage from the nozzle 79 when the sensor body 40 of the detection device 3 notifies that an abnormality is detected in any of the signal delay units 15. .. In this case, a warning sound such as a buzzer may be output instead of the detection indicator lamp 27 or together with the detection indicator lamp 27.

Subsequently, another usage example of the detection device 3 will be described with reference to FIGS. 17 (a) and 17 (b). FIG. 17A is a perspective view of the non-contact power feeding device 80 equipped with the detection device 3 from above, and FIG. 17B is a perspective view of the non-contact power feeding device 80 seen from below.

As shown in FIGS. 17A and 17B, the detection device 3 is mounted on the non-contact power feeding device 80. The non-contact power feeding device 80 is a device for non-contactly charging a vehicle 82 or the like, and has a power transmission coil 83 installed under the ground. The power transmission coil 83 receives power from the power supply device 81 and oscillates at a predetermined frequency to charge the vehicle 82. The energy generated by the oscillation of the power transmission coil 83 is received by the power receiving coil 84 mounted on the vehicle 82 side, and a charger (not shown) mounted on the vehicle 82 is charged.

The non-contact power feeding device 80 includes a detection electrode 85 for detecting a human body, a ground electrode 87 (signal delay unit 15D), and a detection coil 86 for metal detection (signal delay unit 15C). The detection electrode 85, the ground electrode 87, and the detection coil 86 are connected to the sensor main body 40 via a plurality of main body side connection terminal portions 45 provided corresponding to each.

The sensor main body 40 is mounted on the power feeding device 81, and the power feeding device 81 is collectively connected to the power transmission coil 83, the detection electrode 85, the ground electrode 87, the detection coil 86, and the like via wiring 89. The power feeding device 81 is provided with an abnormality notification light 88 that stands out larger than the detection indicator light 27 of the sensor main body 40. Also in this case, a warning sound such as a buzzer may be output together with the abnormality notification lamp 88.

The detection electrode 85 for detecting the human body is provided in a disk shape on the outer peripheral portion of the power transmission coil 83. This makes it possible to detect a person who has invaded the periphery of the power transmission coil 83.

The ground electrode 87 is arranged closer to the vehicle 82 than the detection coil 86 and the detection electrode 85 for detecting the human body. Since the car body of the car 82 is made of metal, the capacitance is affected by the metal. However, by providing the ground electrode 87 between the car 82 and the detection electrode 85, the influence of the car body of the car 82 can be reduced and the human body or The presence of liquid can be detected with high accuracy.

The detection coil 86 is provided on the outer peripheral side of the power transmission coil 83 and inside the detection electrode 85 for detecting a human body.

If a metal body invades a place where an electromagnetic field is generated during power supply, the metal body melts due to the influence of electromagnetic waves and causes a failure. In addition, it is dangerous if a person intrudes into a place where an electromagnetic field is generated during power supply. Further, if a dangerous substance gasoline or a liquid that causes an electric leakage enters between the detection electrode 85 and the ground electrode 87, it may cause a fire or an electric leakage.

In the above configuration, when the control unit (not shown) of the non-contact power supply device 80 is notified by the sensor main body 40 of the detection device 3 that an abnormality has been detected by any of the signal delay units 15, the power supply device 81 Stop the power supply from. As a result, when it is detected that some abnormality has occurred during power feeding, the non-contact power feeding device 80 can immediately stop the power feeding to ensure safety.

In this embodiment, a configuration in which a plurality of main body side connection terminal portions 45 of the sensor main body 20 provided with the microprocessor 24 of the first embodiment are provided is exemplified, but the time-voltage conversion unit 32 of the second embodiment is provided. A plurality of main body side connection terminal portions 45 of the sensor main body 30 may be provided.

1, 2, 3 Detection device 10 Detection attachment 10A, 10D Human body detection attachment 10B Liquid detection attachment 10C Metal detection attachment 12 Parts side connection terminal 13 PET bottle 14 Holder 15 Signal delay 15A, 15D Human body detection signal Delay part (human body detection part)
15B Liquid detection signal delay unit (liquid detection unit)
15C Metal detection signal delay unit (metal detection unit)
15A1, 15B1, 15D1, 71, 74, 85 Detection electrodes 15A2, 15B3, 15C2, 15D3 resistors (passive elements)
15B2, 15D2, 73, 87 Ground electrode (reference potential electrode)
15C1,76,86 Detection coil 20,30,40 Sensor body (detection device body)
21, 31 Reference pulse generation unit 22 Delay pulse generation unit 23 Pulse synthesis unit 24 microprocessor (measurement judgment unit)
25 Offset adjustment button 27 Detection indicator 32 Hours-voltage conversion unit 33 Waveform smoothing unit 34 Voltage judgment unit 45 Main unit side connection terminal unit 46 Main unit side connection terminal unit (simultaneous connection unit)
60 Charger 70 Beverage maker 80 Non-contact power feeding device 81 Power feeding device 83 Power transmission coil 84 Power receiving coil

Claims (7)

At least one of a human body detector that extracts signal changes due to the presence or absence of a human body, a liquid detector that extracts signal changes depending on the amount or type of liquid, and a metal detector that extracts signal changes due to the presence or absence of metal.
It has a human body detection unit, a liquid detection unit, and a detection device main body to which the metal detection unit can be arbitrarily attached.
The human body detection unit extracts the change in capacitance due to the approach of the human body as a delay change in the signal.
The liquid detection unit extracts the change in capacitance due to the difference in the amount or type of liquid as a delayed change in the signal.
The metal detection unit extracts the change in the magnetic field due to the approach of the metal as the delay change of the signal.
The detection device body is
A reference pulse generator that generates a reference pulse,
A delay pulse generation unit that generates a delay change of a signal extracted by the human body detection unit, the liquid detection unit, or the metal detection unit as a delay pulse.
A pulse synthesizer that extracts the pulse time difference between the reference pulse and the delayed pulse, and
A measurement determination unit that measures the pulse time difference to determine the presence or absence of detection,
A detection device including a human body detection unit, a liquid detection unit, or a connection terminal unit that enables insertion of the metal detection unit into a pulse transmission path of the delay pulse generation unit. The human body detection unit
A detection electrode for detecting changes in capacitance and
Passive elements for converting capacitance changes as signal delay changes,
The detection device according to claim 1 , further comprising a reference potential electrode connected to the reference potential of the detection device main body. The liquid detector is
A detection electrode for detecting changes in capacitance and
Passive elements for converting capacitance changes as signal delay changes,
The detection device according to claim 1 or 2, further comprising a reference potential electrode connected to the reference potential of the detection device main body. The metal detection unit is
A detection coil for detecting magnetic field changes and
The detection device according to any one of claims 1 to 3 , further comprising a passive element for converting a change in a magnetic field as a change in delay of a signal. Any one of claims 1 to 4 , wherein the detection device main body includes a simultaneous connection unit for simultaneously connecting at least two of the human body detection unit, the liquid detection unit, and the metal detection unit to the detection device main body. The detection device according to item 1. The invention according to any one of claims 1 to 5, further comprising an offset amount adjusting unit for adjusting the offset amount of the pulse time difference generated by the parasitic capacitance and the steady magnetic field near the human body detecting unit, the liquid detecting unit or the metal detecting unit. Detection device. The detection device according to any one of claims 1 to 6, further comprising a sensitivity adjustment mechanism that accepts sensitivity adjustment from the outside of the detection device main body.

Images