JP2016184253A - Coin processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus capable of performing coin detection of high reliability without being affected by dust or dirt in air even when a coin tray is in such a shape that it is hard to take change out, and also relatively long in distance to a coin which is made of nonmagnetic metal.SOLUTION: A remaining coin detection sensor 12 is arranged below a bottom surface part 14 of a coin tray 10, and an electromagnetic wave of high frequency is normally emitted from an oscillation coil 32 of an LC oscillation circuit toward the tray bottom surface part. A microcomputer measures an oscillation frequency of the LC oscillation circuit successively, and the measured oscillation frequency is compared with a reference frequency stored in a memory so as to determine whether an oscillation frequency increasing when coins C1, C2 are present in a coin tray becomes a programmed value higher than the reference frequency, thereby outputting a coin residue signal when the oscillation frequency becomes the set value higher than the reference frequency.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cash vending machine, an automatic ticket vending machine, an ATM, a POS register, a change handling machine such as a change machine in a self-service gas station, a change machine, etc. The present invention relates to a coin processing device that detects whether or not coins remain in a coin tray in order to prevent forgetting or leaving them out.

  In vending machines, POS registers, etc., if the user forgets to change the coins that have been thrown from the coin outlet to the coin tray when the price is settled, or if the cashier staff leave it, it will cause problems. In order to avoid this, a processing apparatus that automatically detects and notifies whether or not coins remain in the coin tray is used. For example, a coin processing device (a change dispenser) configured to pay out coins stored in a housing from a payout opening, and has a bottom face and four sides of the bottom face to be paid out to a payout opening. A tray that can receive coins and collect them on the bottom is provided. A magnetic sensor with a coil wound around a core is placed on the back side of the bottom, and the coil is connected to the LC oscillation circuit. When the coin detection circuit is configured by the circuit and the control unit, and the drive voltage is applied to the coin detection circuit and the coin is on the bottom surface of the tray, the inductance and impedance change due to the electromagnetic induction action of the coil. The output from the LC oscillation circuit is rectified by a rectifier circuit to form a pulse waveform, and the presence or absence of coins remaining on the bottom of the tray is detected by detecting this pulse waveform with the control unit. In the apparatus it has been proposed (e.g., see Patent Document 1.).

  Further, a coin payout outlet for paying out coins is formed at the end of the apparatus main body having a coin storage portion therein, and the coin payout is paid out to the lower part of the coin payout outlet at the end of the apparatus main body. A light receiving side slit in which a coin receiving / receiving part having a substantially horizontal bottom surface for receiving coins is formed and a light sensor composed of a light receiving element and a light emitting element is provided, and the light receiving element and the light emitting element of the light sensor are formed in the coin paying / receiving part. In addition, a coin depositing and dispensing device is proposed that is disposed so as to face the light emitting side slits and detects the presence or absence of coins on the bottom surface of the coin dispensing and receiving unit by this optical sensor (see, for example, Patent Document 2). .) Furthermore, a coin passage is connected to a coin dispensing port of a money changer or a vending machine, and a detection sensor which is a capacitance type non-contact sensor is disposed in the coin passage, and an oscillation circuit and a buffer circuit are provided in the detection sensor. A sensor control unit configured to include a current detection resistor element, a differential amplifier, a detection circuit, an A / D converter, a CPU, a D / A converter, etc. Controls the operation of the detection sensor that detects a change in the generated capacitance, outputs a detection signal according to the output signal of the detection sensor, and the sensor output determination unit causes a coin path or coin withdrawal based on the detection signal. A coin residual detection device that determines the presence of coins remaining in the mouth has been proposed (see, for example, Patent Document 3).

Japanese Patent No. 5434422 (page 3-4, FIG. 2 to FIG. 5) JP 2012-242978 A (page 3-4, FIG. 4) JP 2009-193090 A (page 5-8, FIG. 4, FIG. 7)

However, as described in Patent Document 1, the conventional coin processing device using a magnetic sensor for coin detection has the following various problems.
That is, in the coin processing device, a plurality of types of coins stored in the housing are combined so as to be equal to the difference obtained by subtracting the purchase amount from the payment amount, and the solenoid built in the device is activated. Then, the change process is performed by changing the change from the payout outlet to the coin tray. Therefore, the inner surface of the coin tray, which is usually made of plastic, is roughened in a short time from the start of use due to impact scratches and wear caused by metal coins. For this reason, the coins thrown into the coin tray hardly slide down to the position directly above the magnetic sensor at the center of the bottom surface of the tray.

  In addition, since coins are repeatedly removed from the coin tray by hand, dirt and grease are adhered to the inner surface of the tray. In addition, since the coin tray, which is a plastic molded product, is charged with a large amount of static electricity by forced convection of air or natural convection by an air conditioner, dust and dust in the air are collected and attached to the coin tray. The adhesion of these dirt, grease, and dust also makes it difficult for coins to slide on the slope of the tray. In this way, the inner surface of the coin tray with the surface roughened and with dirt, grease or dust attached to the surface was made of coins, particularly aluminum having an outer shape of 20 mm, a thickness of 1.5 mm and a weight of only about 1 g. It is very rare and not possible for a one-yen coin to slide down in accordance with gravity and to move pinpointly to a horizontal bottom surface having only the same outer diameter as the coin. This is one of the factors that make it difficult to put a coin processing device that uses a magnetic sensor to detect coins into practical use.

  Moreover, the magnetic sensor is generally made so as to detect a magnetic metal body such as iron or nickel. The detection of the metal body by this magnetic sensor is based on the principle that the oscillation gain of the oscillation circuit is reduced by the high-frequency eddy current loss generated in the metal body with the approach of the metal body to the coil. We are using. Then, the oscillation gain of the high-frequency oscillation circuit is always rectified by a rectifier circuit (detection circuit) and then smoothed. The smoothed DC voltage is reduced by the approach of the metal body to the coil. In comparison with a preset comparison voltage, when the DC voltage decreases by a certain value or more, it is switched and output as a metal body approach signal. However, non-magnetic metals such as aluminum, copper, and copper alloys are used as the material of coins worldwide in Japan. This metal body made of aluminum, copper, or copper alloy generates high-frequency eddy currents, but since its electrical resistance is very small, eddy current loss is very small, so a decrease in the oscillation gain of the high-frequency oscillation circuit is detected. Difficult to do. For this reason, the detection distance of coins made of non-magnetic metal such as aluminum, copper or copper alloy detected by a magnetic sensor is the same as the detection distance of coins made of magnetic metal such as iron or nickel of the same size and shape. Coins using a magnetic sensor for detecting coins, which are only about 1 / 2.5 to 1/3 of the distance, and are inferior in reliability and impractical to use magnetic sensors for coin detection. This is one of the factors that makes it impossible to put the processing device into practical use.

  Next, as for the usage environment and situation of the coin processing device, as described above, the coin tray is made of a plastic molded product, so the tray is charged with a large amount of static electricity only by forced air convection or natural convection by the air conditioner. , Dust and dirt in the air are collected near the tray. In particular, when the place where the coin processing apparatus is used is crowded, the influence is great, and the amount of dust and dirt floating in the air becomes very large during the dry season of winter. For this reason, in the coin processing device that detects coins using an optical sensor as described in Patent Document 2, when dust collected near the tray adheres to the light receiving element and the light emitting element of the optical sensor, The light sensor will not pass light in a short period of time. As a result, there is a problem that even when there is no coin in the coin tray, a malfunction signal indicating that there is a coin is output, and the optical sensor hardly functions. Also, the dust and dirt collected in the coin tray are subject to repeated removal of the change from the tray through the hand of the person, causing sweat, dirt or rain attached to the light receiving side slit or light emitting side slit of the tray during the rainy season. Dust and dust are gradually accumulated and solidified due to the humidity of the water. In such a case, maintenance work associated with cleaning and removal is necessary, but the work is very troublesome, and the labor costs of field engineers who investigate the cause of malfunction and deal with repairs are high. There is a problem such as.

  In addition, even in a coin processing apparatus using a capacitance method as described in Patent Document 3, when a large amount of dust or dust floats adheres to the coin tray, the coupling capacity between the electrodes via the coin is detected. Since it is inversely proportional to the distance between the electrode and the coin, there is a problem that the detection capacity signal for coin detection is greatly attenuated and it is very difficult to detect the presence or absence of a coin.

  The present invention has been made in view of the circumstances as described above, and it is possible to detect coins even if the bottom surface of the coin tray is sufficiently wide compared to the size of the coins so that change can be easily taken out. Coin made of non-magnetic metal such as aluminum, copper, copper alloy, etc., and can detect coins with high reliability even if the distance to the coin is relatively large, It is possible to detect the presence or absence of remaining coins without being affected by dust or dust at all, and it is also possible to detect remaining coins after stopping on an inclined surface in the coin tray. An object of the present invention is to provide a coin processing apparatus that eliminates the need for cleaning / maintenance work of a section.

In the present invention, in order to achieve the above object,
B) Do not use dust or dust-sensitive optical sensors or capacitive sensors to detect coins.
B) Do not use magnetic sensors that are not suitable for detecting coins made of non-magnetic metals such as aluminum, copper, and copper alloys with low electrical resistance and low high-frequency eddy current loss.
C) Even if the material of the coin is a non-magnetic metal, such a coin is irradiated with a high-frequency electromagnetic wave to generate a high-frequency eddy current in the coin, and the high-frequency electromagnetic wave generated by the eddy current generated in the coin is oscillated. Coin detection is performed using the principle that the oscillation coil receives the high-frequency electromagnetic wave and the oscillation coil receives the high-frequency electromagnetic wave, thereby reducing the self-inductance of the oscillation circuit and increasing the oscillation frequency of the oscillation circuit.
Also,
D) For example, the coin is placed on the front surface of the oscillation coil so that the distance between the oscillation coil for coin detection and the detected coin is large and a coin on a wide surface in the coin tray can be detected. Measure the oscillation frequency of the oscillation circuit when it does not exist in advance, store it in the memory, store it in the memory, use it as the reference frequency, and compare the amount of increase when the oscillation frequency of the oscillation circuit increases with the reference frequency The coin was detected.

  In other words, the invention according to claim 1 detects the presence or absence of remaining coins discharged from the coin outlet of the money handling machine and inserted into the coin tray to prevent artificial forgetting or leaving of coins. In the coin processing apparatus, the periphery of the oscillation coil of the LC oscillation circuit is magnetically shielded except for the side surface serving as the detection surface, and the oscillation coil is disposed such that the side surface serving as the detection surface faces the bottom surface of the coin tray. A coin residual detection sensor unit that constantly radiates a high-frequency electromagnetic wave from the oscillation coil toward the bottom surface of the coin tray, and a memory that stores a reference frequency of the LC oscillation circuit, The oscillation frequency of the LC oscillation circuit is sequentially measured, and the measured oscillation frequency is compared with the reference frequency stored in the memory, so that coins remain in the coin tray. When the oscillation frequency of the LC oscillation circuit, which rises when the electromagnetic wave generated by the eddy current generated in the coin is reflected and coupled to the oscillation coil, becomes higher than the value programmed for the reference frequency. And a microcomputer that outputs a residual signal of coins when the oscillation frequency of the LC oscillation circuit becomes higher than a set value with respect to the reference frequency.

  The invention according to claim 2 is the coin processing device according to claim 1, wherein the oscillation frequency of the LC oscillation circuit measured when no coins remain in the coin tray is stored in a memory and is used as a reference It is characterized by frequency.

  According to a third aspect of the present invention, in the coin processing device according to the second aspect, the oscillation frequency of the LC oscillation circuit that is increased by the coin remaining in the coin tray is stored in the memory by the microcomputer. It is characterized in that it is determined that the frequency is higher than 0.02% of the reference frequency and a residual signal of coins is output.

  The invention according to claim 4 is the coin processing apparatus according to claim 2 or claim 3, wherein it is artificially confirmed that no coin remains in the coin tray, and the power is turned on to the microcomputer so that the voltage is increased. The power is reset automatically by the electronic hardware circuit, the program starts, the initial setting of parameters, etc. is completed, and the oscillation frequency of the LC oscillation circuit measured once at the beginning of operation is stored in the memory. Is a reference frequency.

  According to a fifth aspect of the present invention, in the coin processing device according to the second or third aspect, the LC oscillation is measured twice or more at a predetermined time interval at the beginning of operation after the microcomputer power is reset. The frequency obtained by averaging the oscillation frequency of the circuit is stored in a memory and used as a reference frequency.

  The invention according to claim 6 is the coin processing apparatus according to claim 2 or 3, wherein the oscillation frequency of the LC oscillation circuit measured every time the program passes through the main routine is stored in the memory at that time. When there is a variation within a predetermined range with respect to the reference frequency, the average value of the newly measured oscillation frequency and the reference frequency stored in the memory is calculated, and the average frequency is used as the reference frequency. The reference frequency stored in the memory is replaced with the reference frequency so far, and the reference frequency stored in the memory is repeatedly updated.

  The invention according to claim 7 is characterized in that, in the coin processing device according to claim 1, a fixed value oscillation frequency set and inputted in advance is stored in a memory and used as a reference frequency.

  According to an eighth aspect of the present invention, in the coin processing device according to any one of the first to seventh aspects, when the oscillation operation of the LC oscillation circuit is stopped, it is detected and the coins remain in the coin tray. It is characterized by comprising notifying means for outputting a signal for notifying that the presence or absence of the signal cannot be detected.

  In the coin processing device according to the first aspect of the invention, when the high frequency electromagnetic wave is irradiated from the oscillation coil of the coin residual detection sensor unit toward the bottom surface of the coin tray, and the coin remains in the coin tray, the oscillation occurs. The coin receives a high-frequency electromagnetic wave irradiated from the coil, an eddy current is generated in the coin, and the electromagnetic wave generated by the eddy current generated in the coin and the electromagnetic wave by the oscillation coil itself are coupled in high frequency. At this time, the electromagnetic wave generated by the oscillation coil and the electromagnetic wave generated by the eddy current in the coin are electrically out of phase by 180 °, so that it depends on the amount of the high-frequency electromagnetic wave transmitted from the coin and received by the oscillation coil. Thus, the self-inductance of the LC oscillation circuit is apparently reduced. The oscillation frequency of the LC oscillation circuit increases in accordance with the decrease amount of the self-inductance of the LC oscillation circuit. Then, in the microcomputer, the oscillation frequency of the LC oscillation circuit is sequentially measured, the measured oscillation frequency is compared with the reference frequency stored in the memory, and the oscillation frequency of the LC oscillation circuit is programmed with respect to the reference frequency. It is determined whether or not the value has become higher than the set value, and a residual signal of coins is output when the oscillation frequency of the LC oscillation circuit becomes higher than the set value with respect to the reference frequency. In this way, the presence or absence of remaining coins discharged from the coin outlet of the money handling machine and inserted into the coin tray is detected.

  Therefore, when this coin processing apparatus is used, the coin tray is made of a non-magnetic metal such as aluminum, copper, copper alloy, etc., even if the bottom surface thereof is sufficiently wide compared to the size of the coin to make it easy to take out change. Even if the distance between the coin and the coin is relatively large, the coin remaining in the coin tray can be detected with high reliability, and an optical sensor or a capacitance sensor is not used. Therefore, it is possible to detect the presence or absence of remaining coins without being affected at all by dust or dust in the air, and it is also possible to detect remaining coins that have stopped on an inclined surface in the coin tray. And in this coin processing apparatus, the cleaning / maintenance work of a coin residual detection sensor part becomes unnecessary.

  In the coin processing device of the invention according to claim 2, the oscillation frequency of the LC oscillation circuit measured when no coin remains in the coin tray is set as the reference frequency, and the oscillation frequency of the LC oscillation circuit measured sequentially By comparing with the reference frequency, the presence or absence of remaining coins in the coin tray is reliably detected.

  In the coin processing apparatus of the invention according to claim 3, the oscillation frequency of the LC oscillation circuit that is sequentially measured is measured and stored in the memory when the coin does not remain in the coin tray. Since the remaining signal of coins is output when the frequency becomes higher than the 0.02% frequency value with respect to the reference frequency, It is possible to detect a 1-yen coin (aluminum coin having a diameter of 20 mm and a thickness of 1.5 mm), which is the smallest coin in Japan, with sufficient reliability.

  In the coin processing device of the invention according to claim 4, the oscillation frequency of the LC oscillation circuit that is sequentially measured and the fact that no coins remain in the coin tray are confirmed, and the LC oscillation circuit of the LC oscillation circuit is started at the beginning of the operation of the microcomputer. By measuring the oscillation frequency and comparing it with the reference frequency stored in the memory, it is reliably detected whether or not coins remain in the coin tray.

  In the coin processing apparatus of the invention according to claim 5, the reference frequency to be compared with the oscillation frequency of the LC oscillation circuit that is sequentially measured is twice or more at a predetermined time interval in a state where no coin remains in the coin tray. Since the measured oscillation frequency of the LC oscillation circuit is an averaged frequency, it is possible to avoid the occurrence of erroneous detection due to the influence on the oscillation frequency due to electrical noise or the like.

  In the coin processing device of the invention according to claim 6, since the reference frequency compared with the oscillation frequency of the LC oscillation circuit that is sequentially measured is repeatedly updated, the coin tray is affected by the influence of power supply drift, ambient temperature, and the like. It can be avoided that the oscillation frequency in a state in which no coins remain therein gradually changes, deviates from the reference frequency stored in the memory, and erroneously outputs a coin detection signal.

  In the coin processing device according to the seventh aspect of the invention, since the fixed oscillation frequency set and inputted in advance is used as the reference frequency, the capacity of the ROM and RAM required for detecting the presence or absence of remaining coins is reduced. The apparatus cost can be reduced, and calculation processing such as measurement of the oscillation frequency of the LC oscillation circuit when no coins remain in the coin tray and averaging thereof can be omitted.

  In the coin processing device according to the eighth aspect of the invention, when the oscillating operation of the LC oscillation circuit is stopped, it is notified that the coin detection function in the coin tray is not working, so that attention is drawn. Increases nature.

1 is an external perspective view of a coin dispensing unit in which an example of an embodiment of the present invention is shown and a coin residual detection sensor unit is provided on a coin tray of a coin processing device. FIG. It is a longitudinal cross-sectional view which shows the structure of the coin dispensing unit shown in FIG. FIG. 3 is a perspective view showing the coin dispensing unit shown in FIGS. 1 and 2 separated into a coin tray and a coin residual detection sensor unit. It is a perspective view which shows one example of the coil bobbin used for the oscillation coil of LC oscillation circuit. An example of the ferrite pot core which magnetically shields the oscillation coil of the LC oscillation circuit is shown, (a) is a perspective view seen from the front side, and (b) is a perspective view seen from the back side. An example of the electromagnetic shielding board for performing the leakage flux countermeasure of the ferrite pot core which magnetically shields the oscillation coil of LC oscillation circuit is shown, (a) is a top view, (b) is a side view. It is a block diagram which shows an example of the circuit structure of the coin processing apparatus which concerns on embodiment of this invention. It is a flowchart which shows an example of the program for detecting the remainder of the coin in a coin tray in the coin processing apparatus which concerns on embodiment of this invention. In the coin dispensing unit shown in FIGS. 1 and 2, when the 1-yen coin approaches the oscillation coil in a posture inclined by 30 ° with respect to the detection surface of the coin residual detection sensor unit, the oscillation frequency of the LC oscillation circuit is the reference. It is a graph which shows the change curve of a position when becoming only 0.02% and 0.04% with respect to a frequency. FIG. 3 is a schematic diagram for explaining a change in the position / posture of a one-yen coin in a coin tray in the coin dispensing unit shown in FIGS. 1 and 2. It is a flowchart which shows another example of the program for detecting the remainder of the coin in a coin tray in the coin processing apparatus which concerns on embodiment of this invention. It is a flowchart which shows another example of the program for detecting the remainder of the coin in a coin tray in the coin processing apparatus which concerns on embodiment of this invention. It is a flowchart which shows another example of the program for detecting the remainder of the coin in a coin tray in the coin processing apparatus which concerns on embodiment of this invention. It is a flowchart which shows an example of the program for outputting the alerting | reporting signal, when the LC oscillation circuit stops in the coin processing apparatus which concerns on embodiment of this invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
This coin processing device, for example, a change dispensing device, includes a coin tray 10 and a coin (change) residual detection sensor as shown in FIG. 1 as an external perspective view, as shown in FIG. 2, as a longitudinal sectional view, and as shown in FIG. A coin dispensing unit including the unit 12 is provided.

  The coin tray 10 is constituted by a horizontal bottom surface portion 14 having a relatively large area, a slope portion 16 protruding to the front side and curved, and a vertical back surface portion 18 in which a coin payout outlet 20 is formed. The coin tray 10 is attached to a money handling machine main body (not shown) such as a vending machine by screwing the back portion 18 with a plurality of mounting screws 22.

  The coin residual detection sensor unit 12 is connected to the bottom surface part 14 of the coin tray 10 and is integrally attached to the lower part thereof with a mounting screw 24. The coin residual detection sensor unit 12 is configured by housing an oscillation coil 32 (see FIG. 7) of the LC oscillation circuit 30 in a casing 26 having a cylindrical shape and a lower opening surface closed by a cover 28. . The oscillation coil 32 is configured by winding a coil wire around a coil bobbin 34 having a shape as shown in a perspective view in FIG. 4, and a coil wire outlet 36 is formed on the coil bobbin 34. The oscillating coil 32 is housed in a pot core 38 having a shape as shown in FIG. 5A as viewed from the front side and as viewed from the back side in FIG. The pot core 38 is made of ferrite. Therefore, the oscillating coil 32 is magnetically shielded except for one side surface thereof, thereby preventing the selectivity Q from being lowered and the influence of electromagnetic waves induced from the outside. The oscillation coil 32 having the outer peripheral surface and the back surface (lower surface) magnetically shielded with one side left in this manner is formed on the bottom surface portion 14 of the coin tray 10 so that one side surface not magnetically shielded becomes a detection surface. Opposed to each other. In addition, a printed circuit board 42 fixed with mounting screws 44 is disposed inside the casing 26 of the coin residual detection sensor unit 12, a circuit part 46 is disposed below the printed circuit board 42, and a connection connector 48 is disposed on the lower side surface. It has been.

  Here, in actual manufacture of a coin processing device, since a coin residual detection sensor part is provided in a part of a large coin tray, productivity is improved if the coin tray and the coin residual detection sensor part are manufactured integrally. The occurrence of problems such as MTBF in long-term use is often caused by the semiconductor in the coin residual detection sensor unit 12 that uses a large amount of semiconductor. In consideration of these matters, in order to improve productivity and reduce manufacturing costs, and to facilitate maintenance and withstand long-term use, as shown in FIGS. 1 to 3, The coin tray 10 and the coin residual detection sensor part 12 are separated, the coin residual detection sensor part 12 is attached below the bottom part 14 of the coin tray 10, and the oscillation coil 32 of the coin residual detection sensor part 12 is the bottom part of the coin tray 10. If it opposes 14, the convenience will improve more.

  In many cases, a POS register or the like is installed on a metal desk and used, but in this case, the coin residual detection operation may be influenced by a metal desk. In order to eliminate such influence, as shown in a plan view in FIG. 6A and a side view in FIG. 6B, an electromagnetic shield plate 40 formed of a thin copper plate in accordance with the shape of the back surface of the pot core 38 is provided. The high frequency leaked from the ferrite may be shielded with a conductor by sticking to the back side (the opposite side of the detection surface) of the pot core 38 through the adhesive applied to the one side.

  The oscillation coil 32 of the coin residual detection sensor unit 12 constitutes an oscillation coil of the LC oscillation circuit 30 as shown in a block diagram in FIG. The LC oscillation circuit 30 is connected to the microcomputer 50 via a waveform shaping Schmitt trigger circuit U1. The microcomputer 50 includes a memory 52 that stores a predetermined program and a reference frequency of an LC oscillation circuit 30 described later. In the microcomputer 50, the oscillation frequency of the LC oscillation circuit 30 is sequentially measured, and the measured oscillation frequency is compared with a reference frequency stored in the memory 52, and a predetermined calculation process as described later is performed. The signal is appropriately output from the output unit via the signal output power transistor QP. Reference sign OS1 in FIG. 7 is a precise oscillator, CS and RS are integration capacitors and charging resistors for setting a reset time, DS is a rapid discharge diode of the integration capacitor, and VCC is a DC power supply voltage. Show. These functions and operations will be described later.

Next, in this coin processing apparatus, processing operation and detection for detecting the presence or absence of remaining coins (changes) ejected from coin outlets of coin handling machines such as vending machines and POS registers and put into the coin tray 10 The principle will be specifically described.
In vending machines, POS registers, etc., if the amount paid by the user is greater than the total purchase amount, the difference is automatically calculated and combined so that multiple types of coins are equivalent to the difference, The solenoid is actuated, and a plurality of coins are paid and returned to the coin tray 10 through the coin payout outlet 20 as change. As shown in FIG. 2, the coins C1 and C2 thrown into the coin tray 10 slide down on the inner surface of the slope portion 16, and usually fall on the bottom portion 14 and accumulate in a horizontal posture.

  An oscillation coil 32 of the coin residual detection sensor unit 12 is disposed below the bottom surface part 14 of the coin tray 10 in which the coins C1 and C2 are accumulated. The oscillation coil 32 constitutes an oscillation coil of the LC oscillation circuit 30 as shown in FIG. 7, and the oscillation frequency F (Hz) of the LC oscillation circuit 30 is such that the inductance of the oscillation coil 32 is L (H), LC When the capacitance of an oscillation capacitor (not shown) of the oscillation circuit 30 is C (F), it is expressed by the general calculation formula shown in Equation 1.

  As shown by the above formula, the oscillation coil 32 always oscillates at the oscillation frequency F determined by the constant of the inductance L of the oscillation coil and the capacitance C of the oscillation capacitor. A high-frequency electromagnetic wave φG is irradiated from the oscillation coil 32 that constantly oscillates toward the bottom surface portion 14 of the coin tray 10 in which the coins C1 and C2 are stored. When the coin C exists on the bottom surface portion 14 of the coin tray 10 irradiated with the high frequency electromagnetic wave φG, the frequency of the electromagnetic wave φG irradiated on the coin C is determined by the high frequency electromagnetic wave φG irradiated from the oscillation coil 32. The same high frequency eddy current is generated. Since the coin C is made of aluminum, copper, or copper alloy having a low electrical resistance, the eddy current generated in the coin C has a small eddy current loss. When the generated eddy current flows in the coin C, a high-frequency electromagnetic wave φCI is generated again in the coin C, and the high-frequency electromagnetic wave φCI is reflected toward the oscillation coil 32.

  The oscillation coil 32 and the coin C have a coupling coefficient that is influenced by the size of the coin C and the approach distance of the coin C to the oscillation coil 32, and are coupled by high-frequency electromagnetic waves. The phases of the electromagnetic wave φG irradiated from the oscillation coil 32 and the electromagnetic wave φCI generated by the eddy current of the coin C are electrically shifted by 180 °. Therefore, the mutual inductance between the two becomes negative, and the self-inductance in the LC oscillation circuit 30 decreases as the coin C approaches the oscillation coil 32 as compared to when the coin C does not approach the oscillation coil 32. The oscillation frequency of the LC oscillation circuit 30 is increased. That is, the greater the number of coins C and the closer the distance between the oscillation coil 32 and the coins C, the more the self-inductance of the oscillation coil 32 decreases, and the oscillation frequency of the LC oscillation circuit 30 accordingly increases. Get higher. As the oscillation frequency of the LC oscillation circuit 30 is higher, the difference in the frequency change due to the approach of the coin C becomes larger, but the frequency changes according to the electrical principle described above. The ratio of the change in the oscillation frequency is approximately constant regardless of the magnitude of the oscillation frequency.

  In the LC oscillation circuit 30, oscillation is continued at a frequency due to the self-inductance determined by the remaining amount of the coin C and the distance between the oscillation coil 32 and the coin C. In order to know how high the oscillation frequency at that time is, it is necessary to compare the oscillation frequency with a reference oscillation frequency. As this reference frequency, the oscillation frequency when there is no coin in the coin tray 10 is used. That is, the oscillation frequency when no coins remain in the coin tray 10 is measured in advance, and the measured value is input to the memory 52 and stored and stored in the memory 52 as a reference frequency for comparison. By comparing the value of the reference frequency stored in the memory 52 with the constantly oscillating frequency, the increase amount is detected when the sequentially measured oscillation frequency becomes high, and the increase amount is detected as the reference frequency. When the value becomes larger than the set value, a coin detection signal is used.

A processing operation for coin detection in the coin processing device will be described based on a flowchart excluding the redundant functional unit shown in FIG.
When using this coin processing apparatus, the commercial power supply is turned on after confirming that no coins remain in the coin tray 10. As a result, a predetermined DC power supply voltage VCC is applied to the detection sensor circuit shown in FIG.

  When the power supply voltage is applied to the detection sensor circuit, the LC oscillation circuit 30 starts to oscillate. Before the microcomputer 50 functions, the power supply voltage VCC is first applied to the integrating capacitor CS via the reset charging resistor RS and charging is started. Until the voltage of the integration capacitor CS becomes a constant voltage value, the microcomputer 50 is subjected to a hard reset and waits for the start of the program. When the voltage of the integration capacitor CS reaches a predetermined voltage value, the microcomputer 50 is released from reset and the program starts its function.

  A high frequency electromagnetic wave φG is generated by the oscillation of the oscillation coil 32 of the LC oscillation circuit 30, and the electromagnetic wave φG is irradiated toward the bottom surface portion 14 of the coin tray 10. At this time, since it is confirmed that no coins are present in the coin tray 10, the power is turned on, so that the oscillation frequency F (Hz) is the inductance L (H) of the oscillation coil 32 and the capacitance C of the oscillation capacitor. The oscillation coil 32 oscillates at the oscillation frequency F expressed by the mathematical formula 1 shown in Equation (1).

Since the oscillation coil 32 oscillates with a sine wave, the rising and falling voltages per unit time of the voltage waveform, that is, the value of dV / dT is small, so that the voltage signal from the LC oscillation circuit 30 is directly It is not appropriate to input the frequency measurement signal to the microcomputer 50 composed of CMOS. Thus, the signal of the oscillation waveform of the oscillation coil 32 is processed into a signal having a sudden rising and falling rectangular wave via the Schmitt trigger circuit U1 and input to the microcomputer 50. On the other hand, after the power reset is completed, the microcomputer 50 performs initial setting of parameters and the like in order to make the system function as instructed, and outputs a signal L indicating that no coin is present, by measuring the oscillation frequencies F ₁ in the absence, and stores and store in memory 52 the oscillation frequencies F ₁ as the reference frequency F _C.

The method of measuring the oscillation frequency will be specifically described.
For example, when the LC oscillation circuit 30 is oscillating at a constant frequency, if the oscillation frequency is measured after waiting for one second, the measurement takes too much time and is not practical in terms of program. Therefore, in order to measure the oscillation frequency with high accuracy in a short time, in this detection sensor circuit, the time required for the designated number of cycles is high in accuracy and is higher by one digit or more than the oscillation frequency of the LC oscillation circuit 30. After precisely counting using the number of clocks generated by the oscillator OS1, it is converted to a frequency. For example, when measuring an oscillation frequency of 200,000 Hz, 20,000 cycles that require a time of approximately 0.1 seconds are designated by the program and measured. First, a 5,000,000 Hz clock is created by performing frequency division using the 20,000,000 Hz oscillator OS1. When counting with this 5,000,000 Hz clock, the above-mentioned 20,000 cycles corresponds to a clock of 500,000 pulses, and one cycle of the oscillation frequency is the number of clocks of 25 pulses. Here, when the oscillation frequency is increased by 40 Hz (0.02%) and changed to 200,040 Hz, when the oscillation frequency of 20,000 cycles specified by the program is measured as described above, the number of clock pulses is 499. , 920, and a change in oscillation frequency that rises by 4 Hz in about 0.1 second can be extracted as a change corresponding to a 25-fold reduction in 100 pulses. Thus, the time counted by the number of clocks is calculated by the microcomputer 50, converted into the oscillation frequency, stored in the memory 52, and the remaining coins are detected. Therefore, it is possible to measure a change in the oscillation frequency below the decimal point in spite of the measurement in a short time.

The oscillation frequencies F ₁ in the absence of coins to a coin tray 10, and measured as described above, after storing and store in memory 52 the oscillation frequencies F ₁ as the reference frequency F _C, to a coin tray 10 for paid out coins is detected whether the remaining, the oscillation frequency F _D of the LC oscillator circuit 30 is measured in the same manner as described above, constantly monitors the change in the oscillation frequency F _D according to a program flow. When the oscillation frequency F _D while monitoring the frequency change increases, the measurement time of the fixed number of cycles specified in the program is shortened. After converting the shortened time increment of the frequency, as compared to the reference frequency F _C that are stored in the memory 52, the operation frequency is, the reference frequency F _C specified by the program with respect to frequency values D The coin residual signal H is output when it becomes larger (F _D ≧ F _C + D). In this frequency measurement a plurality of times in order to avoid malfunction due to electromagnetic noise from the outside (n times), by comparing the measured frequency F _D and the reference frequency F _C confirmed, the state where the oscillation frequency is higher sustained It is also possible to output the coin residual signal H at the time.

  Here, the direct factors that change the oscillation frequency of the LC oscillation circuit 30 when the metal body approaches the oscillation coil 32 are the magnitude of the eddy current generated in the metal body and the approach distance. If the approach distance is constant, the change in the oscillation frequency is affected by the magnitude of the eddy current. The magnitude of this eddy current is affected by the area of the approaching metal body. The smaller the area of the metal body, the smaller the eddy current becomes, and the smaller the oscillation frequency changes. Therefore, a detection sensor that functions sufficiently even for the smallest coin is required, but the smallest coin distributed in the country is a one-yen coin.

  In general, the coin tray 10 used in the market has a bottom surface portion 14 of a circular shape having a diameter of about 30 mm. Thus, when the tray bottom surface portion 14 has a circular shape of 30 mmφ, coins are likely to be concentrated on the tray bottom surface portion 14, so that the outer diameter of the oscillation coil 32 for detection is optimally 30 mmφ. Since the ferrite pot core 38 for magnetically shielding the oscillation coil 32 having an outer diameter of 30 mmφ is formed of a sintered alloy, a certain thickness is required to prevent the crack, and an oscillation having an outer diameter of 30 mmφ is required. The outer diameter of the pot core 38 that houses the coil 32 is generally about 36 mmφ.

  FIG. 9 shows a coin that causes trouble such as insufficient change when the bottom surface portion 14 of the coin tray 10 has a circular shape of 30 mmφ, the outer diameter of the oscillation coil 32 is 30 mmφ, and the outer diameter of the pot core 38 is 36 mmφ. 1 yen in which the change rate of the oscillation frequency of the LC oscillation circuit 30 is 0.02% and 0.04% when the largest 1-yen coin C is tilted by 30 ° with respect to the bottom of the tray. The position curve of the coin C is shown. Here, the rate of change is obtained by dividing the increase in frequency by the reference frequency, and the rate of change = [(measured oscillation frequency−reference frequency) ÷ reference frequency] × 100. In FIG. 9, x indicates the position point P (● part) of the bottom edge of the one-yen coin C in a posture inclined by 30 ° with respect to the bottom of the tray when the oscillation frequency increases by 0.04%. Indicates the position point P (● part) of the bottom edge of the one-yen coin C in a posture inclined by 30 ° with respect to the bottom of the tray when the oscillation frequency rises by 0.02%. FIG. 9 shows that when the position point P of the bottom edge of the one-yen coin C in a posture inclined by 30 ° with respect to the bottom surface of the tray is below the curve connecting the positions indicated by x, the oscillation frequency is 0. When the position point P of the bottom edge of the one-yen coin C in a posture inclined by 30 ° with respect to the bottom surface of the tray is below the curve connecting the positions indicated by ○, It shows that the oscillation frequency rises to 0.02% or more. Accordingly, when the 1-yen coin C is in the coin tray 10 at the position / posture shown in FIG. 10A, assuming that the oscillation frequency increases by 0.02%, (b), ( For the 1-yen coin C in each position and orientation shown in c) and (d), the oscillation frequency will rise to a value greater than 0.02%.

  As shown in FIGS. 1 and 2, a general coin tray 10 mainly used in the market has a circular shape with a depth of about 45 mm and a bottom surface portion 14 of about 30 mmφ, and an upper take-out opening portion is about It is a plastic molded product that is 100 mm × 100 mm and is formed into a curved surface so that coins can be easily taken out, and its thickness is approximately 2.5 mm. As shown in FIG. 2, when the coin C1 paid out as change remains on the bottom surface portion 14 of the coin tray 10 in a horizontal position, it is easy to detect the coin, and trouble such as leaving the change is also caused. Few. On the other hand, the coin C2 mainly remaining on the slope portion 16 near the bottom surface portion 14 of the coin tray 10 and the coin C remaining on the slope portion 16 as shown in FIG. There are many shortage problems. The inner surface of the coin tray 10 has a curved surface so that the slope 16 near the bottom surface 14 and the change remaining on the slope 16 can be easily taken out. For this reason, the slope part 16 close to the bottom face part 14 and the coins C on the slope part 16 remain with a gradient of about 30 ° with respect to the bottom face of the tray. Therefore, as can be seen from FIG. 9 and the above description, in order to be able to always detect the coin C remaining in the coin tray 10, a change (increase amount) in the oscillation frequency set by the program. Is preferably 0.02% or more with respect to the reference frequency in view of the safety factor. Therefore, in this coin processing apparatus, in order to satisfy the function of the detection sensor circuit, the coin residual signal is set to be output when the oscillation frequency rises to 0.02% or more of the reference frequency.

  In this case, in the method of counting the number of clock pulses using a CR clock circuit built in the microcomputer 50 and converting it to a frequency, the oscillation frequency as small as 0.02% as described above is used. It is difficult to calculate and measure changes with high accuracy. For this reason, in this detection sensor circuit, as described in detail above, a precise oscillator OS1 having a high accuracy and a stable frequency is used, and the oscillation frequency is measured by counting with a high precision clock divided by the frequency. To do.

  Moreover, in a coin processing apparatus, the reliability at the time of coin detection is often greatly influenced by its installation location and usage conditions. For example, when a cashier at a POS register wears synthetic fiber or woolen clothes during a dry season in winter, the human body is charged with tens of thousands of volts of static electricity, and the coins for change are made of plastic. The inside of the completed coin processing apparatus is charged with a large voltage static electricity by moving while receiving friction and impact, and is discharged in the vicinity of the oscillation coil 32 for detection. Further, when a change dispensing solenoid located in the vicinity of the coin tray 10 is operated, a very large electromagnetic pulse noise is generated from the solenoid, and the noise is input to the oscillation coil 32. Then, at the timing when the microcomputer 50 measures the reference frequency by chance, static electricity is discharged to the coin tray 10 located immediately above the coin residual detection sensor unit 12 to generate a nozzle, or electromagnetic noise is generated from the solenoid. If so, the reference frequency measured and stored in the memory 52 becomes a high value different from the true value, though it is very rare. As a result, when a coin is detected based on the reference frequency, a malfunction may occur such that the coin cannot be detected even though the coin remains in the coin tray 10.

In order to avoid these problems, the oscillation frequency when no coin is present in the coin tray 10 is measured a plurality of times, an average value of the plurality of measurement frequencies is calculated, and the average value is stored in the memory 52. The average value of the frequencies stored in the memory 52 may be used as the reference frequency. For example, as shown in a flow chart, except for the redundant function unit 11 performs a first measurement of the oscillation frequencies F ₁ in a state where coins to the coin tray 10 in does not remain, elapsed from the measurement point When the time T reaches the programmed time value S (T ≧ S), the second oscillation frequency F ₂ is measured, and the average value of the _two frequency values F ₁ and F ₂ [(F ₁ + _{F 2)} to calculate the ÷ 2], and stores the stored in the memory 52 and the average value _{F C} as the reference frequency _{F C.} Then, using the reference frequency F _C, the above description and the same program shown in a flowchart of FIG. 8, to perform the detect whether the coin does not remain in the coin tray 10.

  In general, a coin processing apparatus having a coin tray is used in various environments, and the environmental condition affects the measurement of the oscillation frequency. For example, when a coin processing device is installed in a place with high humidity in summer, moisture enters the oscillation coil 32 of the LC oscillation circuit 30 for detection until the air conditioner is fully functioned and dehumidified. To do. The moisture that has entered the oscillation coil 32 has a large relative dielectric constant εs, so that the inter-winding distributed capacity of the oscillation coil 32 is greatly increased. When the distributed capacity between the windings of the oscillation coil 32 is increased, the capacity of the LC oscillation circuit 30 is increased, so that the oscillation frequency is decreased. On the other hand, when the dehumidification of the surrounding environment is completed, the distributed capacity between the windings of the oscillation coil 32 becomes smaller than before, and the inter-winding capacity of the oscillation coil 32 decreases, so that the oscillation frequency increases. In addition to humidity, the temperature of the surrounding environment similarly affects the oscillation frequency. The physical factor is that the distribution capacity between the windings changes due to the pressure between the windings due to the expansion and contraction of the winding wire due to the temperature rise and fall, and the oscillation transistor used in the LC oscillation circuit 30 The oscillation frequency is also affected by changes in the parameters. In particular, in a highly sensitive detection sensor that detects the presence or absence of coins by a change in oscillation frequency of about 0.02%, the influence of these cannot be ignored.

  In order to eliminate the influence of the environmental conditions as described above, after confirming that no coin is present in the coin tray 10 after the power is turned on, the oscillation frequency measured a plurality of times is averaged, and the average value is used as the reference frequency. Is stored in the memory 52, and the reference frequency is compared with the oscillation frequency measured to constantly monitor the presence / absence of coins according to the routine of the program to determine the presence / absence of coins. When the oscillation frequency measured for the determination of the presence / absence of coins does not increase so much as to indicate the remaining coins and the difference from the reference frequency stored in the memory 52 is slight, the measured frequency was measured. An average value is calculated by performing an operation using the oscillation frequency and the reference frequency stored in the memory 52, the calculated average value is replaced with the reference frequency stored in the memory 52, and the new reference frequency is stored in the memory 52. Store and remember. By doing so, the reference frequency is corrected every time the program makes a round, and erroneous detection of coins remaining is prevented.

For example, when the oscillation coil 32 is oscillating with no coins remaining in the coin tray 10, as shown in the flowchart in FIG. 12 excluding redundant functional units, the first oscillation frequency F ₁ When the program-set time S has elapsed from the time of measurement (T ≧ S), the second oscillation frequency F ₂ is measured. Then, after confirming that the _second oscillation frequency F ₂ is within a predetermined range (± A) with respect to the _first oscillation frequency F ₁ , the average value of the _two frequency values F ₁ and F ₂ [ _(F 1 + _{F 2)} to calculate the ÷ 2], and stores the stored in the memory 52 and the average value _{F C} as the reference frequency _{F C.} Then, when the oscillator coil 32 has elapsed time is programmed in a state where the oscillation S (T ≧ S), measures the oscillation frequency F _N, measured oscillation frequency F _N is the reference frequency F _C On the other hand, the frequency rises more than a predetermined frequency value D set for the coin residual signal by the program (F _N ≧ F _C + D), and the oscillation frequency F _N is measured n times at a predetermined time interval S and measured. comparing the frequency F _N and the reference frequency F _C, a coin residual signal H when measured oscillation frequency F _N is state becomes higher than a predetermined frequency value D relative to the reference frequency F _C is sustained Output.

On the other hand, a small change in measurement frequency F _N with respect to the reference frequency F _C, reduces the frequency at the reference frequency predetermined range GM set in the program as a correction _{(F N ≧ F C -GM)} , it is programmed When the frequency rises within the predetermined range GP (GP <D) (F _N ≦ F _C + GP), the average value of the reference frequency F _C and the measurement frequency F _N stored in the memory 52 until then [ (F _C + F _N ) ÷ 2] is calculated, and the average value is stored in the memory 52 as a new reference frequency F _C so that the reference frequency is switched. The measured oscillation frequency _{F N} is reduced beyond a predetermined range GM with respect to the reference frequency _{F C (F N <F C} -GM), also from and a predetermined frequency value D exceeds the predetermined range GP When rising slightly (F _C + D> F _N > F _C + GP), the change in the oscillation frequency F _N is ignored.

In the above-described flowchart for calculating the average value, an example is shown in which a simple average of two measurement frequency values is calculated. However, if there is room in the capacity of the ROM or RAM, a large number of measurements are performed to avoid erroneous detection. It is also possible to perform averaging using values and various methods. Further, in the flowchart shown in FIG. 12, when a coin rise is detected by discriminating an increase in frequency equal to or higher than a predetermined value, a coin residual signal H is output after confirming n coins remaining in order to avoid malfunction. However, depending on the capacity of the ROM or RAM, n = 1, that is, there is no problem even if the detection signal is output so as to confirm the remaining coin once, and in that case, the program of that part is skipped. It is also possible. In the description described above, the frequency band changes in the measured oscillation frequency F _N is ignored is also a frequently occurring phenomenon in extraction near the end of the beginning and change the coin is struck to the coin tray 10.

Next, a case where a fixed reference frequency is set by a program at the time of manufacturing the apparatus to reduce the apparatus cost will be described.
That is, in the production of a coin processing device, since the specific gravity of the cost for the coin detection sensor is high, it may be necessary to design it to be inexpensive. In this case, the part that occupies a large weight in the cost of the coin detection sensor is a microcomputer. In order to manufacture this microcomputer at a low cost, it is necessary to use an inexpensive one-chip microcomputer with few ROMs and RAMs constituting the microcomputer. When producing a coin detection sensor used in a coin processing device, the oscillation frequency when the coin is not approaching the coin tray is within a certain range even by managing the constant variation of parts used in the LC oscillation circuit. Can be suppressed. In addition, when producing a detection sensor, it is also possible to perform detailed frequency adjustment using a variable capacitor in the capacitor of the LC oscillation circuit. When it is possible to adjust the oscillation frequency in detail, if the frequency is written and stored in the memory as a fixed reference frequency, the measurement of the reference frequency and the measured oscillation frequency in the RAM are stored in the program. There is no need to write or calculate the average value of multiple measurement frequencies to set the reference frequency, and a low-capacity ROM and RAM one-chip microcomputer is used to manufacture a coin detection sensor at low cost. can do.
13, by setting the reference frequency of the fixed value in the program, using a reference frequency F _C of the set fixed value, coins remaining by comparing the oscillation frequency F _D and the reference frequency F _C, which is measured The flowchart in the case of detecting is shown.

  In addition, at the start of use of a POS register equipped with this coin processing device, the device is erroneously operated with the key of the cash box or the commuter car being placed on the coin tray from which change is paid out. There is also. A ring-shaped metal body made of a spring that binds a key or a key is often made of a magnetic metal or plated with a magnetic metal or the like. When high-frequency electromagnetic waves are irradiated from the oscillation coil toward the coin tray with keys or the like made of magnetic metal with high electrical resistance such as nickel placed on the coin tray, their magnetic properties Since metal has high electrical resistance and high frequency loss, eddy currents are consumed in these magnetic metals, and the selectivity Q of the oscillation coil is lowered, so that the oscillation gain of the LC oscillation circuit cannot be maintained, and oscillation is stopped. A big problem occurs.

  On the other hand, in the use of a coin processing device for a long period of time, it is rare but unavoidable that defects in reliability of transistors and other circuit parts used in the oscillation circuit occur. Basically, it is configured to output a detection signal of residual coins by utilizing the fact that the oscillation frequency of the LC oscillation circuit increases as the coin approaches the detection oscillation coil. An alarm may not be generated even though the coin detection sensor is not functioning at all due to the oscillation stop of the oscillation circuit. In order to solve such problems, it is preferable to monitor the oscillation stop according to the program flow and to generate an alarm when the oscillation stops. FIG. 14 shows an example of a flowchart for monitoring the stop of oscillation except for redundant functional units.

  The use of vending machines and vending machines such as tickets and admission tickets are progressing with the aim of resolving problems due to labor shortages and reducing labor costs. In order to eliminate troubles such as forgetting to leave or left behind, the coin processing apparatus according to the present invention is installed in various money handling machines such as vending machines, automatic ticket vending machines, ATMs, POS registers, change return machines, currency exchange machines, etc. The present invention is widely used in fields such as industrial machinery.

DESCRIPTION OF SYMBOLS 10 Coin tray 12 Coin residual detection sensor part 14 Coin tray bottom part 16 Coin tray slope part 20 Coin dispensing outlet 26 Casing 30 LC oscillation circuit 32 Oscillation coil 34 Coil bobbin 38 Pot core 40 Electromagnetic shield board 42 Printed circuit board 46 Circuit part 50 Micro Computer 52 Memory C, C1, C2 Coin U1 Waveform shaping Schmitt trigger circuit QP Signal output power transistor OS1 Oscillator VCC DC power supply voltage φG High frequency electromagnetic wave irradiated from oscillation coil φCI Generated by eddy current generated in coin High frequency electromagnetic waves

Claims (8)

In the coin processing device which detects the presence or absence of the remaining coins discharged from the coin outlet of the money handling machine and inserted into the coin tray, and prevents artificial forgetting or leaving of coins,
The periphery of the oscillation coil of the LC oscillation circuit is magnetically shielded with the side surface serving as a detection surface, and the oscillation coil is configured such that the side surface serving as the detection surface faces the bottom surface of the coin tray. A coin residual detection sensor unit that constantly radiates high-frequency electromagnetic waves from the oscillation coil toward the bottom surface of the coin tray;
A memory for storing a reference frequency of the LC oscillation circuit; sequentially measuring an oscillation frequency of the LC oscillation circuit; comparing the measured oscillation frequency with a reference frequency stored in the memory; When coins remain in the tray, the oscillation frequency of the LC oscillation circuit that rises when the electromagnetic wave generated by the eddy current generated in the coin is reflected and coupled to the oscillation coil is programmed with respect to the reference frequency. A microcomputer that determines whether or not the frequency is higher than a set value and outputs a residual signal of coins when the oscillation frequency of the LC oscillation circuit is higher than a set value with respect to a reference frequency;
A coin processing apparatus comprising: 2. The coin processing device according to claim 1, wherein the reference frequency stored in the memory is an oscillation frequency of the LC oscillation circuit measured when no coin remains in the coin tray. In the microcomputer, the oscillation frequency of the LC oscillation circuit, which rises when coins remain in the coin tray, is 0.02% or more of the reference frequency stored in the memory. The coin processing apparatus according to claim 2, wherein the coin processing device outputs a residual signal of coins by determining that it has become high. The reference frequency stored in the memory is activated after it is confirmed that no coins remain in the coin tray, the microcomputer is turned on, voltage is applied, power is reset, and initial setting is completed. The coin processing device according to claim 2 or 3, wherein the coin processing device is an oscillation frequency of the LC oscillation circuit that is measured once in an initial stage. The reference frequency stored in the memory is a frequency obtained by averaging the oscillation frequency of the LC oscillation circuit measured twice or more at a predetermined time interval at the beginning of operation after the microcomputer is reset. The coin processing device according to claim 2, wherein the coin processing device is a coin processing device. The reference frequency stored in the memory is
The oscillation frequency newly measured when the oscillation frequency of the LC oscillation circuit measured every time the program passes through the routine is within a predetermined range with respect to the reference frequency stored in the memory at that time. And the average value of the reference frequency stored in the memory is calculated and replaced by the frequency of the average value,
The coin processing device according to claim 2 or 3, wherein the reference frequency stored in the memory is repeatedly updated. The coin processing apparatus according to claim 1, wherein the reference frequency stored in the memory is a fixed oscillation frequency set and input in advance. An informing means for outputting a signal for informing that when the oscillation operation of the LC oscillation circuit is stopped and detecting whether or not coins remain in the coin tray cannot be detected. The coin processing device according to any one of claims 1 to 7.

Images