JPH076250A - Coin detector - Google Patents

Abstract

PURPOSE:To provide the coin detector able to accurately detect the presence of coins regardless of dispersion in the electric characteristic of a magnetic sensor and the difference from an installed condition of a mounted device. CONSTITUTION:In the coin detector provided with a magnetic sensor 10 sensing the effect of a coin K on a magnetic field and with a detection section 30 detecting at least one of presence, passing and non-passing of the coin K by comparing a sensor output of the magnetic sensor 10 with a compared value stored in advance, the detection section 30 has a correction section 30 correcting the compared value depending on a sensor output of the magnetic sensor 10 when the effect of the coin K on the magnetic field is not caused.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided in, for example, a coin mechanism of an automatic vending machine, a money changer, or the like, and detects the influence of coins on a magnetic field to detect the presence / absence, passage / non-passage and type of coins. The present invention relates to a coin detecting device for detecting at least one element.

[0002]

2. Description of the Related Art A coin mechanism of a vending machine is equipped with a change holding unit for holding inserted coins for change, and this change holding unit is provided with a coin detecting device for detecting a change out. Has been. This coin detecting device is provided at the lower end of the coin holding cylinder, and detects a magnetic sensor that detects the effect of the held coins on the magnetic field, and monitors the sensor output of the magnetic sensor to hold a predetermined number of coins. By utilizing that the sensor output value changes according to an increase in the number of coins held, the detection unit stores the changed sensor output value in advance. When the value of the sensor output is larger than the comparison value, it is detected that only the number of coins less than the predetermined number is held, and the change-out is detected. In this case, a fixed value obtained from past experience is used as the comparison value.

[0003]

By the way, even if the magnetic sensors are the same, they are easily affected by variations in electrical characteristics due to manufacturing, ambient temperature, humidity, etc. The sensor output fluctuates due to differences in installation conditions. In such a case, in the above-described conventional coin detection device, since fixed comparison values are uniformly stored in all the detection units of the same type, variations occur even if the same magnetic sensor is used. That is, the value of the sensor output of the magnetic sensor does not become larger than the comparison value even when the number of held coins is less than the predetermined number, or it does not become smaller than the comparison value when the number of coins is more than the predetermined number. , Detection error was easy to occur. Further, even if the variation in electrical characteristics is compensated for at the mounting position of the magnetic sensor, high mounting accuracy is required.

The present invention has been made in view of the above problems, and accurately detects the presence or absence of a coin, etc., regardless of variations in the electrical characteristics of the magnetic sensor and differences in the installation conditions of the mounted devices. It is an object of the present invention to provide a coin detection device that can be used.

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned object,
The coin detecting device according to the present invention compares the presence / absence, passing / non-passing, and type of a coin by comparing the sensor output value of the magnetic sensor for detecting the influence of the coin on the magnetic field with the comparison value stored in advance. In the coin detection device including a detection unit that detects at least one of the elements, the detection unit has a correction unit that corrects the comparison value based on the sensor output value of the magnetic sensor when the magnetic field of the coin is not affected. It is characterized by

[0006]

According to the coin detecting device of the present invention, the magnetic sensor detects the influence of the coin on the magnetic field, and the detecting section is
A value corresponding to the sensor output of the magnetic sensor is compared with the stored comparison value to detect at least one element of presence / absence / non-passage and type of coin. In this case, the correction unit corrects the comparison value based on the sensor output value of the magnetic sensor when the coin does not affect the magnetic field. The presence or absence of coins can be detected while automatically absorbing the changes.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coin detecting device according to an embodiment of the present invention will be described in detail below with reference to the drawings. This coin detection device is of a type to be installed in a vending machine.
(A), (b) has each shown the front view and cutting side view of the coin mechanism 1 of a vending machine. This coin mechanism 1 is connected to the coin insertion slot 2 opened to the outside for inserting the coin K, the coin identification section 3 located below the coin insertion slot 2, and the coin identification section 3 to connect the inserted coins K. Four change pipes 4a, 4b, 4c, 4d (hereinafter collectively referred to as "change pipes 4") that hold a part as coins for change according to denomination, and are arranged at the lower end of each change pipe 4. Wound coil 7,7 using a pot core
.. and an oscillating circuit disposed on the back surface of the coin mechanism 1 and having the coil 7 as a part of the constituent elements, and a detecting unit for detecting whether or not the coin K is held from the change of the oscillating voltage of the oscillating circuit. It is composed of a printed circuit board 8 on which the electronic circuit section 5 is mounted.

The change pipes 4a to 4d are not particularly limited, but in the present embodiment, denominations of 10 yen, 50 yen, 100 yen and 500 yen are reserved respectively. Further, coin replenishment ports 6, 6 ... for replenishing coins K for change are provided on the upper front surface of each change pipe 4.

The coil 7 is out of change when a predetermined number of coins K stacked and retained on the change pipe 4 have been reached, for example, 10 or less (hereinafter, 10 will be referred to as a predetermined number). When a coin “absence” signal is output as, when the number of coins K of at least 2 to 3 increases or decreases with 10 coins as the center, the change of the magnetic field of the coil 7 ... It is arranged at each of the height positions that are linear.

An outline of the coin detecting operation in the change pipe 4 will be described. When a coin K is inserted into the coin insertion slot 3, the coin K is held in the change pipes 4a to 4d for each type of coin. Then, the electronic circuit section 5 changes the oscillating voltage of the oscillating circuit which changes when the coin K held in the change pipe 4 cuts off the magnetic field of the coil 7, so that the coin K held in the coin storing section becomes 10 When it is detected that the number of coins is equal to or less than the number of coins, a coin "no" signal is output so that the vending machine body displays an indication that the change is out.

Next, regarding the electric circuit of the electronic circuit section 5,
Explaining with reference to FIGS. 2 and 6, the electronic circuit unit 5 includes a coin detection sensor circuit (magnetic sensor) 10 that detects an oscillation voltage of an oscillation circuit, and a detection unit that detects whether or not a predetermined number of coins are held. (Detection unit, correction unit) 30.

First, the coin detection sensor circuit 10 will be described with reference to FIG. This coin detection sensor circuit 10
Are oscillator circuits 11a, 11b, 11c, 11d (hereinafter,
(Collectively referred to as “oscillation circuit 11”), the analog switch 12 connected to each output section of the oscillation circuit 11, the amplifier circuit 14 connected to the output section of the analog switch 12 via the capacitor 13, Peak hold circuit 15 and peak hold circuit 1 connected to the output section
5 is mainly composed of a subtraction circuit 16 connected to the output section. The output unit of the subtraction circuit 16 is the detection unit 3
It is connected to the 0 input section.

Explaining the above components, the oscillator circuits 11a to 11d are LRC oscillator circuits each including an amplifier 21, a resistor 22, capacitors 23 and 24, and a coil 7 arranged in the change pipe 4. It oscillates at a predetermined frequency determined by the constants of the capacitors 23 and 24, and the amplitude of the oscillated voltage changes according to the internal loss of the coil 7. That is, when the internal loss of the coil 7 is large, the amplitude of the oscillation voltage is small, and when the internal loss of the coil 7 is small, the amplitude of the oscillation voltage is large.

FIG. 3 shows an oscillation voltage waveform of the oscillation circuit 11. In the figure, the vertical axis represents the oscillation voltage of the oscillation circuit,
The horizontal axis represents time. In the figure, when the coin K does not block the magnetic field of the coil 7, since the loss of the coil 7 is small, the amplitude of the oscillating voltage (2 × (Vs−Ve1)) is obtained as shown in the waveform on the left side of the figure. Is the maximum. On the other hand, when a certain number of coins K are retained in the change pipe 4, the magnetic field of the coil 7 is cut off, and the loss of the coil 7 increases, and as shown on the right side of FIG. The amplitude becomes small (in this example, 10 sheets are shown).

The analog switch 12 selects the oscillator circuit 11 corresponding to the decode signal from the four oscillator circuits 11 by the binary coded decode signals 1 and 2 output from the detection unit 30 via the decode signal line 25. Then, the oscillation voltage is output to the amplifier circuit 14.

The capacitor 13 is the analog switch 12
The oscillation voltage obtained by cutting the bias voltage is output to the amplifier circuit 14. As a result, the oscillation voltage waveform shown in FIG. 3 becomes a voltage waveform as shown in FIG. In the figure, the vertical axis represents the input voltage of the amplifier circuit 14, and the horizontal axis represents time. In the figure, the DC component is converted from Ve1 to Ve2 because the DC component Ve1 is cut by the capacitor 13 and the offset voltage Ve2 is added by the power supply 26.

The amplifier circuit 14 amplifies the AC component of the voltage shown in FIG. 4 by Gv and outputs it to the peak hold circuit 15.

The peak hold circuit 15 has a peak value (Gv × (Vs-V) of the voltage obtained by amplifying the voltage waveform shown in FIG.
It holds e1) + Ve2) and outputs this voltage to the subtraction circuit 16.

The subtraction circuit 16 is a peak hold circuit 15
The offset voltage Ve2 is subtracted from the voltage output from the output terminal to output the maximum amplitude signal to the detection unit 30. 5 shows the voltage waveform of the maximum amplitude signal output from the subtraction circuit 16, where the vertical axis shows the voltage value and the horizontal axis shows the time. According to this, the maximum voltage of the maximum amplitude signal when the coin K does not block the magnetic field is Gv × (Vs−Ve1), which is 10
When a coin K is held in the change pipe 4, the voltage becomes as shown on the right side of FIG. That is, a voltage that is Gv times the peak voltage of the AC component of the oscillation voltage shown in FIG. 3 is output.

Next, the structure of the detection unit 30 will be described with reference to the block diagram of FIG. The detection unit 30 includes a microprocessor (hereinafter, referred to as “CPU”) 31 that performs various control operations including operations as a coin detection unit and a correction unit, and a maximum amplitude signal from the subtraction circuit 16 from an analog signal to a digital signal. And convert the converted data to CPU
A / D converter 32 for outputting to 31 and ROM 33, RAM respectively connected to CPU 31 via a bus line
34 and EEPROM 35.

Further, to the CPU 31, the main body control unit 36 of the vending machine is connected by a denomination presence / absence signal line, a coin presence / absence signal for each denomination is output, and a reference value set switch 37 is connected to the coin K. Is set in the change pipe 4, a reference value set signal for setting the converted data as a reference value is input, and the A / D converter 32 receives a temperature for temperature-compensating the converted data. The compensation circuit 38 is connected.

Next, the basic operation of the electronic circuit section 5 will be described with reference to FIGS. 6 and 2. First, when the reference value set switch 37 is pressed while the coin K is not held in the change pipe 4, the CPU 31 stores the conversion data of all denominations at that time in the EEPROM 35 as reference value data (comparison value). Let Next, the CPU 31
When the coin K is accepted, the decode signal is output to the analog switch 12 to select the oscillation circuit. The selected oscillator circuit 11 is connected to the amplifier circuit 14, and the oscillator circuit 11
After the oscillation voltage is amplified, the maximum amplitude signal is output to the CPU 31 as conversion data by the A / D converter 32. The CPU 31 stores the input conversion data as standby value data in a predetermined address of the RAM 34. Further, the CPU 31 periodically changes the decode signal by a timer interrupt, and finally stores the standby value data of all denominations in the RAM 34. When changing this decode signal, the CPU 31 causes the peak hold circuit 1 to
The reset signal is output to 5 and the peak hold circuit 1
The hold voltage of 5 is initialized. Further, the CPU 31
The pressed state of the reference value set switch 36 is constantly monitored, and when the reference value set switch 36 is pressed, the RAM 3
The standby value data at that time stored in 4 is stored in the EEPROM.
It is transferred to a predetermined address of 35 and stored (corrected) as new reference value data. The reference value setting switch 36 is pressed when the coin K is not held in the change pipe 4. After that, when the power is turned off and then turned on again, the CPU 31 causes the EEPRO
The reference value data stored in M35 is read, and the data is stored in a predetermined address of the RAM 34 as reference value data.

Further, the CPU 31 always generates the standby value data for each denomination, compares the standby value data with the reference value data for each denomination, and obtains the value obtained by subtracting the standby value data from the reference value data. A coin “present” signal is output to the main body control unit 36 when it is larger than the determination value preset in the ROM 33 for each denomination, and a coin “absence” signal is output when it is smaller than the determination value. Here, the judgment value will be described.
This determination value is a value of a difference in oscillation voltage of the oscillation circuit between when there are no coins 4 in the change pipe 4 and when a predetermined number of coins K are held, and is measured in advance by an experiment. . This utilizes the fact that the difference value hardly changes even when the oscillation output of the oscillation circuit 11 itself changes due to various causes. That is, when the oscillating voltage of the oscillating circuit drops, the conversion data in the state where the coin K is not held in the change pipe 4 is measured, and if this is used as the reference value, the value obtained by subtracting the determination value from this reference value. And the standby value data are compared, it is accurately detected whether or not a predetermined number of coins K are held.

Next, the above-mentioned EEPROM 35 and R
The memory map of the AM 34 will be described with reference to FIG. FIG. 7A shows a storage area of the EEPROM 35. The EEPROM 35 is provided with a storage area corresponding to 10 yen to 500 yen, and a forward voltage of a diode of a temperature compensation circuit described later and an oscillation corresponding thereto. A storage area for storing temperature compensation data for compensating the oscillation voltage of the circuit 11 is provided. Also, FIG.
(B) shows the storage area of the standby value data and the reference value data of the RAM 34. According to this, the standby data storage area is provided with a storage area for each denomination of 10 yen to 500 yen and corresponds to this. A storage area for storing the reference value data is provided.

Next, the coin detecting operation will be described in detail with reference to the flow charts of FIGS. 8 and 9. Figure 8 (a)
8 shows a reset process for initializing the data of the CPU 31 when the power is turned on, FIG. 8B shows an initial setting process of the reference value data of the EEPROM 35, and FIG. 9 shows a coin detecting process.

First, the outline of the coin detecting operation will be described. In this operation, the value of the maximum amplitude signal when the coin K is not held in the change pipe 4 is stored as the reference value data, and the maximum value thereof is stored. The value of the difference between the value of the amplitude signal and the value of the maximum amplitude signal when ten coins K are held in the change pipe 4 is set in advance as the determination value of the denomination ROM3.
When the value obtained by subtracting the value of the standby value data from the value of the reference value data is greater than or equal to the determination value, the coin “present” signal is output, and when the value is less than or equal to the determination value, the coin is stored. Outputs a "no" signal.

First, the reset process is shown in FIG.
Describing with reference to FIG.
1 sets the denomination pointer to "0" and E
The reference value data corresponding to the pointer "0" stored in the EPROM 35 is transferred to the reference value data storage area of the RAM 34 (step 51). Next, the CPU 31 monitors whether or not the value of the denomination pointer is "3" or more (step 52), and if it is less than "3", increments the denomination pointer by 1 (step 53). , And returns to step 51 and repeats similar steps. Step 5
In 2, when the value of the denomination pointer is "3" or more, this processing is ended (step 54), and the processing shifts to other processing. The denomination pointers “0” to “3” are 10
It corresponds to yen to 500 yen, respectively.

Next, regarding the initial setting process, FIG.
Will be described with reference to. This process is performed periodically every 3 mSec together with the coin detection process described later. CPU
Reference numeral 31 monitors whether or not the reference value setting switch 36 has been pressed (step 61), and when not pressed,
This processing is ended and coin detection processing is performed (step 6).
2). When the reference value setting switch 36 is pressed in step 61, the CPU 31 sets the denomination pointer to "0" (step 63), and sets the standby value data of the denomination corresponding to the denomination pointer to the reference of the EEPROM 35. It is stored in the value data area (step 64). next,
The CPU 31 uses the reference value data of the EEPROM 35 as RA
It is stored in the reference value data area of M34 (step 6).
5). After that, the CPU 31 monitors whether or not the value of the denomination pointer is "3" or more (step 66), and when it is "3" or more, the present process is terminated and the coin detecting process is performed (step 67). ), If it is less than “3”, the denomination pointer is incremented by 1 (step 68), and step 6
Go to step 4 and repeat the above steps.

In the above-mentioned step 61, the reference value setting switch 36 is pressed in the state where there is no coin K in the change pipe 4, so that the reference value data becomes the oscillation circuit 11. The value corresponds to the maximum amplitude signal determined only by the internal loss of the coil 7.

Next, the coin detection process will be described with reference to FIG. 9. The CPU 31 outputs a decode signal to the analog switch 12 to select the oscillation circuit 11 corresponding to the denomination of the denomination pointer "0". The maximum amplitude signal to A / D
The conversion data converted by the converter 32 is input (step 71). Next, the CPU 31 converts the converted data into R
It is stored in the standby value data storage area of the AM 34 (step 72). After that, the CPU 31 outputs a reset signal to the peak hold circuit 15 to reset the hold voltage (step 73), and then sends a decode signal to select the oscillation circuit 11 corresponding to the denomination of the denomination pointer “1”. It is updated and output (step 74). It should be noted that the reason why the decode signal is output in step 74 is that it is better to select the oscillation circuit 11 as soon as possible in order to stabilize the oscillation state of the oscillation circuit 11 when the next standby value data is fetched. This is because it is preferable.

Next, the CPU 31 subtracts the value of the stand-by data from the value of the reference value data, and determines whether or not the value is equal to or larger than the preset determination value according to the denomination (step 7).
5). The CPU 31 outputs a coin “present” signal to the main body control unit 36 when the subtraction result in step 75 is equal to or larger than the determination value (step 76), and outputs a coin “absence” signal when it is smaller than the determination value. Output to the main body control unit 36 (step 7)
7). This completes this process for one denomination,
This processing is performed for all four denominations, and the coin detection processing is ended (step 78).

Next, the operation of the temperature compensating circuit 38 will be described. This circuit is an effective circuit when the number of corrections of the reference value data is reduced, such as when the initial setting process is performed only when the power is turned on. When the oscillating voltage of the oscillating circuit 11 fluctuates due to a change in ambient temperature, etc., and thus the value of the conversion data changes, the temperature compensation data stored in advance causes
The value of the converted data is compensated. Specifically, the forward voltage of the diode built in the temperature compensation circuit 38 is measured, and the magnitude of the oscillation voltage of the oscillation circuit 11 is compensated according to the measured value. For example, -20 ° to + 60 ° C
The forward voltage when a constant current is applied to the diode is stored in the EEPROM 35 within the temperature range of. And
The temperature compensating circuit 38 constantly measures the forward voltage of the diode, obtains the ambient temperature from the forward voltage of the diode at that time, and determines a fixed number of change pipes 4 in the change pipe 4 in the temperature range of -20 ° to + 60 ° C. When the coin 2 is held, the conversion data of the A / D converter 32 is compensated so that the conversion data is always constant. Therefore, even if there are temperature fluctuations,
It is possible to accurately detect coins.

As described above, according to this embodiment, even if the oscillation voltage of the oscillation circuit 11 varies, the CPU 3
1 corrects the reference value data serving as a reference when detecting coins, and compares the corrected reference value data with the standby value data to determine whether or not a predetermined number of coins K are held. It can be detected with high accuracy. Further, since it is not necessary to require high precision for the electronic components used for the oscillation circuit 11, the cost of the device can be reduced.

Further, even if the power of the apparatus is turned off after the initial setting by pressing the reference value setting switch 36, the reference value data is stored in the EEPROM 35,
By performing the initial setting process after the power is turned on again, the RAM 34
Since the previous data is set again in the reference value data storage area, the detection operation can be continued without losing the reference value data.

Further, in the present embodiment, the reference value data and the standby value data are compared and it is monitored whether or not the difference is within the judgment value. However, the judgment value is subtracted from the reference value data. Of course, the subtracted value may be used as the comparison value and the comparison value and the standby value data may be compared. In this case, C
The PU 31 corrects the comparison value every time the reference value data is read.

The present invention is not limited to the above embodiment. For example, the coin detection device is not limited to the presence / absence of coins, and can be applied to the passage of coins and the detection of the type (size of coins).

[0037]

As described above, according to the coin detecting device of the present invention, the presence or absence of a coin can be accurately detected regardless of the variation in the electrical characteristics of the magnetic sensor and the difference in the installation conditions of the mounted devices. can do.

[Brief description of drawings]

FIG. 1 is a front view and a cut side view of a coin mechanism according to the present invention.

FIG. 2 is a block diagram of a coin detection sensor circuit according to the present invention.

FIG. 3 is an oscillation voltage waveform diagram of the oscillation circuit.

FIG. 4 is an input waveform diagram of an amplifier circuit.

FIG. 5 is an output waveform diagram of the subtraction circuit.

FIG. 6 is a block circuit diagram of a detection unit.

FIG. 7 is a memory map diagram of a RAM and an EEPROM.

FIG. 8 is a flowchart of a reset process and an initial setting process.

FIG. 9 is a flowchart of coin detection processing.

[Explanation of Codes] 10 coin detection sensor circuit 30 detection unit 34 RAM 35 EEPROM K coin

Claims (1)

[Claims] 1. A magnetic sensor for detecting the influence of a coin on a magnetic field and the presence or absence of the coin by comparing a sensor output value of the magnetic sensor with a comparison value stored in advance,
In a coin detecting device including a detecting unit for detecting at least one element of passing / non-passing and type, the detecting unit detects the comparison value of the magnetic sensor when the coin does not affect the magnetic field. A coin detection device having a correction unit that corrects according to a sensor output value.