JP2010256245A - Circuit and sensor for detecting electromagnetic fields close to low frequency, and game machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress malfunctions of a proximity switch generated by the approach of electromagnetic field close to a low frequency. <P>SOLUTION: A detection electrode 1 detects an induced voltage generated by an electromagnetic field close to a low frequency, and a coupling circuit 11 connected to the detection electrode in series adjusts the wave height or the level of the induced voltage generated in the detection electrode. The coupling circuit 11 and an LC resonance circuit 12, arranged between a ground potential set a detection allowable frequency of the induced voltage, and a high-frequency oscillation circuit 13 of a current-feedback type oscillates a high-frequency sine wave by an intermediate potential VLC between the coupling circuit 11 and the LC resonance circuit 12. When the electromagnetic field cose to the low frequency is non-irradiated to the detection electrode 1, the high-frequency oscillation circuit 13 set in a negative conductance generating oscillation stop; and when the electromagnetic field near the low frequency is irradiated to the detection electrode 1, the high-frequency oscillation circuit 13 is changed into an oscillation state. The present invention is applicable to game machines. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a low-frequency near electromagnetic field detection circuit, a low-frequency near electromagnetic field detection sensor, and a gaming machine, and in particular, near a low frequency that causes a malfunction in a proximity switch that detects passage of a game ball provided in the gaming machine. The present invention relates to a low-frequency near electromagnetic field detection circuit, a low-frequency near electromagnetic field detection sensor, and a game machine that can detect an electromagnetic field at a timing before a proximity switch malfunctions.

  The pachinko gaming machine is equipped with a plurality of game ball detection switches for detecting a game ball, and outputs a detection signal to the control circuit when the game ball passes through a main winning opening and a gate.

  The mainstream in this game ball detection switch is a direct current 2-wire proximity switch. A linear two-wire proximity switch can be used in the same image as a contact switch by operating in the form of a two-wire open or closed operation, and to detect metal balls in a non-contact manner Since the superiority such as excellent durability is evaluated, it is used more frequently than the game ball detection switch using other principles.

  However, since the proximity switch is configured by an electronic circuit, it has been found in the past that a fraudulent act that exploits a weak point caused by the configuration of the electronic circuit has been detected. For example, if a player deliberately brings a transceiver or mobile phone close to a pachinko gaming machine for improper purposes, the radio wave is emitted to the pachinko gaming machine, and the gaming ball detection switch falls into a functional disorder due to the radio wave. The ball count could be manipulated incorrectly.

  Therefore, as a technology to detect radio waves before the occurrence of the above-mentioned functional failure, a radio wave sensor is installed for each pachinko machine, an antenna is formed with a printed circuit board pattern, and magnetic flux concentration is achieved with a ferrite core, thereby achieving the desired sensitivity. The technology to detect dead radio waves radiated toward the game board surface by securing the insensitive band, but to set the dead band in the LC series resonance circuit to stop the detection operation for the radio waves emitted from mobile phones etc. (See Patent Document 1).

JP 2004-222959 A

  By the way, a recent study has recognized that a game ball detection switch may malfunction due to a relatively low frequency AC noise superimposed on a metal part of a pachinko gaming machine. This AC noise becomes prominent in the band near the resonance frequency of the LC resonance circuit provided in the game ball detection switch, and becomes a problem of matching of the noise band generated naturally. In general, the resonance frequency of the LC resonance circuit is set to 500 kHz to 1.2 MHz, and this resonance frequency band belongs to a low-frequency near electromagnetic field region lower than the radio wave band. Actually, the detection band of the above-described conventional radio wave sensor is 50 Mhz to 2 Ghz, and there is a risk of detection leakage due to band mismatch.

  In the conventional example, the detection wave is detected, and the noise peak value itself is discriminated. In particular, when the resonance frequency and the frequency of the AC noise completely coincide with each other, the adverse effect of the interference wave is enormous, and the game ball detection switch may malfunction before the radio wave sensor reacts. As a countermeasure, a method of reducing the threshold value of the rear-stage discrimination circuit to the limit and preventing minute noise from escaping can be considered, but there is a possibility that the tolerance of other disturbance factors such as electrostatic discharge may be reduced at the same time.

  The present invention has been made in view of such a situation, and the low-frequency near electromagnetic field is generated at the timing before the malfunction of the game ball detection switch is caused by the low-frequency near electromagnetic field generated inside the pachinko gaming machine. By making it possible to detect, it is possible to appropriately monitor the low-frequency near electromagnetic field and to suppress the functional failure of the game ball detection switch.

  A low-frequency near electromagnetic field detection circuit according to one aspect of the present invention is a low-frequency near electromagnetic field detection circuit that is mounted on a pachinko gaming machine and detects a low-frequency near electromagnetic field irradiated from the outside of the pachinko gaming machine. A detection electrode that detects an induced voltage generated by the low-frequency near electromagnetic field, a coupling circuit that is connected in series with the detection electrode and adjusts the wave height or level of the induced voltage generated at the detection electrode, and the coupling A circuit, a band adjustment circuit that is arranged between a ground potential and sets a detection allowable frequency of the induced voltage, and a current feedback type high-frequency oscillation circuit that oscillates a high-frequency sine wave by the voltage output from the band adjustment circuit. The high-frequency oscillation circuit is set to a negative conductance that stops oscillation when the low-frequency near electromagnetic field is not irradiated to the detection electrode; If serial low-frequency electromagnetic field near the irradiation, the high frequency oscillation circuit changes the oscillation state.

  The band adjustment circuit may include an LC resonance circuit, and when the detection electrode is irradiated with the electromagnetic field in the vicinity of the low frequency, only the frequency band near the resonance frequency of the LC resonance circuit. Can be detected in a limited manner.

  The coupling circuit may include a series circuit of a resistor and a capacitor, and the sensitivity of the resistor may be set by changing a resistance value thereof. .

  The detection electrode can include a metal member installed in the pachinko gaming machine or a structure plated with metal.

  The detection electrode may have an annular structure surrounding a board surface of the pachinko gaming machine.

  The low frequency near electromagnetic field detection sensor of the present invention is a low frequency near electromagnetic field detection sensor that is mounted on the pachinko gaming machine and detects a low frequency near electromagnetic field irradiated from the outside of the pachinko gaming machine, The detection signal is output based on the low-frequency near electromagnetic field detection circuit according to any one of Items 1 to 5, the comparison circuit that discriminates the output potential of the low-frequency near electromagnetic field detection circuit, and the state of the comparison circuit And an output circuit.

  A detection electrode connection terminal for connecting the low-frequency electromagnetic field detection sensor and a metal member installed in the pachinko gaming machine or a structure plated with metal can be further included.

  In the gaming machine according to the present invention, the detection electrode connection terminal of the low-frequency near electromagnetic field detection sensor according to claim 7 can be installed on the launch rail.

  In the gaming machine according to the present invention, the low-frequency near electromagnetic field detection sensor according to claim 7 can be installed on a frame ground, and the frame ground can be opened or grounded via a surge protection element. .

  A gaming machine of the present invention is a gaming machine equipped with the low-frequency near electromagnetic field detection circuit according to any one of claims 1 to 5 or the low-frequency near electromagnetic field detection sensor according to any one of claims 6 to 7, wherein When the near-frequency electromagnetic field detection circuit or the low-frequency near electromagnetic field detection sensor detects a low-frequency near electromagnetic field, based on the output signal, a notification for notifying the inside of the gaming machine or the outside of the gaming machine Means can further be included.

  A gaming machine of the present invention includes a low-frequency near electromagnetic field detection circuit according to any one of claims 2 to 5, or a low-frequency near electromagnetic field detection sensor according to any one of claims 6 to 7, and a game ball. A gaming machine including a proximity switch to be detected, wherein a resonance frequency of the LC resonance circuit can be set in the vicinity of an oscillation frequency of the proximity switch.

  In one aspect of the present invention, an inductive voltage that is mounted on the pachinko gaming machine and is detected by an electromagnetic field near the low frequency irradiated from the outside of the pachinko gaming machine, and is generated by the near electromagnetic field near the low frequency by a detection electrode. Is detected and the wave height or level of the induced voltage generated at the detection electrode is adjusted by the coupling circuit connected in series with the detection electrode, and the band adjustment circuit disposed between the coupling circuit and the ground potential is adjusted. A detection allowable frequency of the induced voltage is set, and a high frequency sine wave is oscillated by the high frequency oscillation circuit by the voltage output from the band adjustment circuit, and the high frequency oscillation circuit is near the low frequency with respect to the detection electrode. When the electromagnetic field is not irradiated, the negative conductance is set to stop oscillation. When the electromagnetic field near the low frequency is irradiated to the detection electrode, the high conductance is set. Wave oscillation circuit is changed to the oscillation state.

  The low-frequency near electromagnetic field detection circuit according to one aspect of the present invention is an abnormality detection unit, and the detection electrode for detecting the induced voltage generated by the low-frequency near electromagnetic field is, for example, a metal-plated detection electrode The coupling circuit that is connected in series with the detection electrode and adjusts the wave height or level of the induced voltage generated in the detection electrode is, for example, a circuit in which a resistor and a capacitor are connected in series, and the coupling The band adjustment circuit that is arranged between the circuit and the ground potential and sets the detection allowable frequency of the induced voltage is, for example, an LC resonance circuit, and oscillates a high-frequency sine wave by the voltage output from the band adjustment circuit The current feedback type high frequency oscillation circuit is, for example, a current feedback type high frequency generation circuit including a transistor, a constant current source, and a power source, and the high frequency oscillation circuit is an LC resonance circuit. When the low-frequency near electromagnetic field is not irradiated to the detection electrode, the negative conductance is set to stop oscillation when the detection electrode is configured to have a conductance larger than the conductance of the detection electrode. On the other hand, when the electromagnetic field in the vicinity of the low frequency is irradiated, the high frequency oscillation circuit changes to an oscillation state.

  As a result, by using an LC resonant circuit that has a resonant frequency in the same band as the LC resonant circuit of the proximity switch used to detect the game ball, the low-frequency near electromagnetic field that affects the operation of the proximity switch Is applied, the amplitude of the potential supplied to the high-frequency oscillation circuit increases only in the vicinity of the resonance frequency band. Therefore, it is used for detection of game balls by adjusting the detection sensitivity of the low-frequency electromagnetic field. It becomes possible to detect a low-frequency near electromagnetic field at a timing before affecting the proximity switch.

  According to the present invention, it is possible to appropriately monitor the low-frequency near electromagnetic field arriving at the proximity switch, and it is possible to suppress malfunction of the proximity switch caused by the approach of the low-frequency near electromagnetic field. It is possible to suppress fraud against the machine.

It is a figure explaining the structural example of the pachinko game machine provided with the abnormality detection part which consists of a low frequency near electromagnetic field sensor to which the present invention is applied. It is a figure explaining the structural example of the game ball detection part of FIG. It is a figure explaining the structural example and operation | movement of the conventional abnormality detection part. It is a figure explaining operation | movement of the abnormality detection part of FIG. It is a figure explaining adjustment of the sensitivity of the abnormality detection part of FIG. It is a flowchart explaining an abnormality detection process. It is a figure explaining the other structural example of a detection electrode. It is a figure explaining the other structural example of a detection electrode. It is a figure explaining a detection range. It is a figure explaining the structural example of a connection terminal.

  Embodiments of the present invention will be described below. Correspondences between the configuration requirements of the present invention and the embodiments described in the detailed description of the present invention are exemplified as follows. This description is to confirm that the embodiments supporting the present invention are described in the detailed description of the invention. Accordingly, although there are embodiments that are described in the detailed description of the invention but are not described here as embodiments corresponding to the constituent elements of the present invention, It does not mean that the embodiment does not correspond to the configuration requirements. Conversely, even if an embodiment is described here as corresponding to a configuration requirement, that means that the embodiment does not correspond to a configuration requirement other than the configuration requirement. It's not something to do.

  That is, a low-frequency near electromagnetic field detection circuit according to one aspect of the present invention is mounted on the pachinko gaming machine and detects a low-frequency near electromagnetic field irradiated from the outside of the pachinko gaming machine. (For example, the abnormality detection unit 2 in FIG. 1), the detection electrode for detecting the induced voltage generated by the low-frequency near electromagnetic field, and the induced voltage generated in the detection electrode connected in series with the detection electrode A coupling circuit (for example, the coupling circuit 11 in FIG. 1) for adjusting the wave height or level of the signal, and a band adjustment circuit (for example, for example) that is disposed between the coupling circuit and the ground potential and sets the detection allowable frequency of the induced voltage. LC resonance circuit 12) of FIG. 1 and a current feedback type high frequency oscillation circuit (for example, high frequency oscillation circuit 13 of FIG. 1) that oscillates a high frequency sine wave by the voltage output from the band adjustment circuit, The high-frequency oscillation circuit is set to a negative conductance that stops oscillation when the low-frequency near electromagnetic field is not irradiated to the detection electrode, and the low-frequency near electromagnetic field is irradiated to the detection electrode. In this case, the high-frequency oscillation circuit changes to an oscillation state.

  The band adjustment circuit may include an LC resonance circuit (for example, the LC resonance circuit 12 of FIG. 1), and when the detection electrode is irradiated with the low-frequency near electromagnetic field, Only the frequency band near the resonance frequency of the LC resonance circuit can be limited and detected.

  The coupling circuit may include a series circuit of a resistor and a capacitor (for example, the resistor R1 and the capacitor C1 in FIG. 1), and the resistance value of the resistor is changed. The detection sensitivity can be set.

Hereinafter, the best mode for carrying out the invention (hereinafter referred to as an embodiment) will be described. The description will be given in the following order.
1. First embodiment (example in which the detection electrode is a decorative part with metal plating)
2. Second embodiment (example in which detection electrodes are used as game ball launch rails)

<1. First Embodiment>
[Configuration example of an embodiment of a pachinko gaming machine including an abnormality detection unit including a low-frequency near electromagnetic field sensor to which the present invention is applied]
FIG. 1 shows an example of the configuration of a pachinko gaming machine provided with an abnormality detection unit composed of a low-frequency near electromagnetic field sensor to which the present invention is applied.

  In FIG. 1, a detection electrode 1 for detecting a low-frequency near electromagnetic field, an anomaly detection unit 2 composed of a low-frequency near electromagnetic field sensor, and a peripheral part of a game ball detection unit 5 for detecting a game ball, and these are controlled. A part of the pachinko game machine including the control unit 3 is shown.

  The abnormality detection unit 2 detects the arrival of a low-frequency near electromagnetic field that may affect the game ball detection unit 5 such as a malfunction, and notifies the control unit 3 of the arrival of the electromagnetic wave from the detection electrode 1. In response to this notification, the control unit 3 reports the arrival of a low-frequency near electromagnetic field from the reporting output unit 4 and invalidates the presence or absence of the detection signal of the game ball of the game ball detection unit 5 as an abnormal signal. And By such an operation, an illegal act that forcibly causes the game ball detection unit 5 to malfunction by a low-frequency near electromagnetic field is prevented.

  First, functions realized by the abnormality detection unit 2 will be described.

  The abnormality detection unit 2 detects an induced voltage generated when the detection electrode 1 is exposed to a low-frequency near electromagnetic field, and detects the arrival of a low-frequency near electromagnetic field. The detection electrode 1 is, for example, a decorative part of a pachinko machine with metal plating, which functions as an antenna, and when exposed to a low-frequency electromagnetic field, an eddy current is generated, so that a low-frequency wave can be found everywhere. A near electromagnetic field is secondarily generated, thereby generating an induced voltage.

  The abnormality detection unit 2 includes a coupling circuit 11, an LC resonance circuit 12, a high frequency oscillation circuit 13, a discrimination circuit 14, and an output circuit 15.

  The coupling circuit 11 includes a resistor R1 connected to the detection electrode 1 that functions as an antenna that detects an electromagnetic field in the vicinity of a low frequency, and a capacitor C1 connected in series to the resistor R1, and only a signal having a predetermined frequency or higher is included. Is output to the LC resonance circuit 12. Further, the coupling circuit 11 adjusts the detection sensitivity near the resonance frequency of the low-frequency near electromagnetic field by changing the resistance value of the resistor R1.

  The LC resonance circuit 12 generates an intermediate potential VLC together with the coupling circuit 11 and supplies it to the high frequency oscillation circuit 13. More specifically, the LC resonance circuit 12 includes a resistor R0, a coil L0, and a capacitor C0. One end of the resistor R0 is connected to the other end of the capacitor C1 of the coupling circuit 11, one end of the capacitor C0, the negative terminal of the power source V0, and the collector of the transistor Tr3. The other end of the resistor R0 is connected to the coil L0. One end of the coil L0 is connected to the other end of the resistor R0, and the other end is grounded. One end of the capacitor C0 is connected to the other end of the capacitor C1, one end of the resistor R0, the negative terminal of the power source V0, and the collector of the transistor Tr3, and the other end is grounded. ing.

  The high frequency oscillation circuit 13 oscillates a high frequency signal based on the oscillation frequency of the intermediate potential VLC generated by the coupling circuit 11 and the LC resonance circuit 12 and outputs the high frequency signal to the subsequent discrimination circuit 14. More specifically, the high frequency oscillation circuit 13 includes a constant current source I0, a power source V0, an NPN transistor Tr1, PNP transistors Tr2 to Tr4, and resistors R2 and RE.

  The negative terminal of the power source V0 is connected to the other end of the capacitor C1, one end of the resistor R0, one end of the capacitor C0, and the collector of the transistor Tr3, and the positive terminal is connected to the constant current source I0. The other end is connected to the base of the transistor Tr1. The constant current source I0 has one end connected to the power supply Vcc, the emitters of the transistors Tr2 and Tr3, and one end of the resistor R2, and the other end connected to the base of the transistor Tr1 and the positive power supply V0. Connected to the terminal.

  The base of the transistor Tr1 is connected to the other end of the constant current source I0, the positive terminal of the power source V0, and the base of the transistor Tr4. The collector is connected to the bases of the transistors Tr2 and Tr3 and the collector of the transistor Tr2. Further, the emitter is connected to one end of the resistor RE.

  The base of the transistor Tr2 is connected to the base of the transistor Tr3, the collector of the transistor Tr2, and the collector of the transistor Tr1, and the emitter is one end of the constant current source I0, the emitter of the transistor Tr3, and one end of the resistor R2. And the collector is connected to the bases of the transistors Tr2 and Tr3 and the collector of the transistor Tr1.

  The base of the transistor Tr3 is connected to the base and collector of the transistor Tr2, and the collector of the transistor Tr1, and the emitter is one end of the constant current source I0, the emitter of the transistor Tr2, and one end of the resistor R2. The collector is connected to the negative terminal of the power source V0, one end of the capacitor C0, one end of the resistor R0, and the other end of the capacitor C1.

  The base of the transistor Tr4 is connected to the base of the transistor Tr1, the other end of the constant current source I0, and the positive terminal of the power source V0. The emitter is connected to the other end of the discrimination circuit 14 and the resistor R2, and the collector Is grounded.

  One end of the resistor R2 is connected to the power source Vcc, the emitters of the transistors Tr2 and Tr3, and one end of the constant current source IO, and the other end is connected to the transistor Tr4 emitter and the discrimination circuit 14. The resistor RE has one end connected to the emitter of the transistor Tr1 and the other end grounded. The resistor RE is a sensitivity adjustment resistor that adjusts the sensitivity of the abnormality detection unit 2 by the conductance of the high-frequency oscillation circuit 13.

  The discrimination circuit 14 is supplied with power from the power source Vcc and is grounded, compares the oscillation output supplied from the high frequency oscillation circuit 13 with a predetermined threshold value, and supplies the comparison result to the output circuit 15. The output circuit 15 is supplied with power from the power source Vcc and is grounded, detects a low-frequency near electromagnetic field based on the comparison result of the discrimination circuit 14, and outputs the detection result to the control unit 3 as a signal V1.

  The high-frequency oscillation circuit 13 is set in an oscillation stop state in a normal state, and is set so as to shift to an oscillation state only when the detection electrode 1 is exposed to a low-frequency near electromagnetic field. More specifically, the conductance gL1 of the LC resonance circuit 12 and the conductance gi1 of the high-frequency oscillation circuit 13 are based on the Nyquist oscillation condition, and the high-frequency oscillation circuit 13 is in an oscillation stop state in the following equation (1). In the case of equation (2), the high-frequency oscillation circuit 13 is always in an oscillation state.

gL1> gi1
... (1)

gL1 <gi1
... (2)

  Here, gL1 and gi1 are represented by the following formulas (3) and (4).

gL1 ≒ C0 × R0 / L0
... (3)

gL1≈hfe × A0 / ((2 + hfe) × RE)
... (4)

  Here, C0 is the capacitance of the capacitor C0, R0 is the resistance value of the resistor R0, A0 is the collector current ratio of the transistors Tr2 and Tr3, hfe is the current amplification factor of the transistors Tr2 and Tr3, RE represents the resistance value of the resistor RE.

  Therefore, by adjusting the resistance value of the resistor RE, which is a sensitivity adjustment resistor, the conductance gi1 of the high-frequency oscillation circuit 13 is set to be smaller than the conductance gL1 of the LC resonance circuit 12, that is, the resistor RE is set to be large, The conductance gi1 of the oscillation circuit 13 is set to be small. As a result, since the relationship of the above-described formula (1) can be maintained, the high-frequency oscillation circuit 13 is in an oscillation stop state when the detection electrode 1 is not exposed to the low-frequency near electromagnetic field. At this time, since the high-frequency oscillation circuit 13 is not oscillating, the discrimination circuit 14 is supplied with a value smaller than the threshold value. Therefore, the discrimination circuit 14 indicates that the oscillation operation is not performed. The signal is supplied to the output circuit 15. As a result, the output circuit 15 outputs a signal indicating that the output circuit 15 is not exposed to the low-frequency near electromagnetic field to the control unit 3.

  On the other hand, the detection electrode 1 is exposed to a low-frequency near electromagnetic field to induce a sine wave voltage. At this time, at a frequency near the resonance frequency of the LC resonance circuit 12, the conductance gL1 decreases and shifts from the state of the above equation (1) to the state of the equation (2). And the oscillation output is output to the discrimination circuit 14. At this time, since a value larger than the threshold value is supplied to the discrimination circuit 14, the discrimination circuit 14 supplies a signal indicating that the oscillation operation is performed to the output circuit 15. As a result, the output circuit 15 outputs a signal indicating that the output circuit 15 is exposed to a low-frequency near electromagnetic field to the control unit 3.

[Configuration of Game Ball Detection Unit 5]
Next, a configuration example of the game ball detector 5 will be described with reference to FIG. The game ball detection unit 5 has a configuration similar to that of the abnormality detection unit 1, and includes an LC resonance circuit 112 including a shield member 111, a coil L2, and a capacitor C2, a high-frequency oscillation circuit 113, a discrimination circuit 114, and an output circuit 115. It is configured. The shield member 111 reduces the influence on the coil L2 of an electromagnetic field unnecessary for detection of a game ball. The dotted line represents an electromagnetic field that affects the coil L2. The coil L2 is configured to have substantially the same diameter as the game ball, and the game ball to be detected is configured to pass through the inside of the cavity of the coil L2. Therefore, the game ball detection unit 5 detects the passage of the game ball based on the signal of the coil L2, and supplies the detection result to the control unit 3.

  More specifically, both ends of the capacitor C2 are connected in parallel with the coil L2, and the end portion that becomes the upper voltage is connected to the high-frequency oscillation circuit 113, and the end portion that becomes the lower voltage is grounded. The high-frequency oscillation circuit 113 is supplied with power from the power source and is grounded, and is further grounded via the sensitivity adjustment resistor Re2, and outputs an oscillation output to the discrimination circuit 114. The discrimination circuit 114 is supplied with power from the power source and is grounded, compares the oscillation output supplied from the high-frequency oscillation circuit 113 with a predetermined threshold value, and supplies the comparison result to the output circuit 115. The output circuit 115 is supplied with power from the power source and is grounded, detects the passage of the game ball based on the comparison result of the discrimination circuit 114, and outputs the detection result to the control unit 3 as a signal V2.

  Note that the high-frequency oscillation circuit 113 is set to be in an oscillation stop state when the game ball is in a passing state, and is set to shift to an oscillation state only when the game ball is not passing through. More specifically, the conductance gL2 of the LC resonance circuit 112 and the conductance gi2 of the high-frequency oscillation circuit 113 are based on the Nyquist oscillation condition, and the high-frequency oscillation circuit 113 is in an oscillation stop state in the following equation (5). In the case of Equation (6), the high-frequency oscillation circuit 113 is always in an oscillation state.

gL2> gi2
... (5)

gL2 <gi2
... (6)

  Therefore, by adjusting the resistance value of the sensitivity adjustment resistor Re2, the conductance gi2 of the high-frequency oscillation circuit 113 is set to be smaller than the conductance gL2 of the LC resonance circuit 112, that is, the sensitivity adjustment resistor Re2 is set to be small, and high-frequency oscillation is performed. The conductance gi2 of the circuit 113 is set to be large. As a result, since the relationship of the above-described formula (6) can be maintained, the high-frequency oscillation circuit 113 is always in an oscillation state when the game ball is not passing. At this time, since the high-frequency oscillation circuit 113 performs an oscillation operation, a value larger than the threshold value is supplied to the discrimination circuit 114, and the discrimination circuit 114 is a signal indicating that the oscillation operation is performed. Is supplied to the output circuit 115. As a result, the output circuit 115 outputs a signal indicating that the game ball has not passed to the control unit 3.

  On the other hand, the conductance gL2 rises when the game ball passes through the coil L2, and the state changes from the state of equation (6) to the state of equation (5), so the high frequency oscillation circuit 113 stops oscillation. Then, the oscillation output is output to the discrimination circuit 114. At this time, since a value smaller than the threshold value is supplied to the discrimination circuit 114, the discrimination circuit 114 supplies a signal indicating that the oscillation operation is not performed to the output circuit 115. As a result, the output circuit 115 outputs a signal indicating that a game ball is passing to the control unit 3.

  Further, in order to unify the resonance frequencies of the LC resonance circuits 12 and 112, the coils L0 and L2, the capacitors C0 and C2, and the resistor R0 are adjusted.

  With such a configuration, the resonant frequencies of the LC resonant circuits 12 and 112 are set to values that are very similar to each other, so that abnormalities are reliably detected with respect to the induced electromagnetic waves in the same band as the induced electromagnetic waves that affect the game ball detector 5. In addition to being detectable, radio waves that do not naturally affect the game ball detector 5 can be reliably undetected, so that an abnormal state due to other factors can hardly be erroneously detected.

[Operation of conventional abnormality detection unit]
Next, in describing the operation of the abnormality detection unit 2, the operation of the abnormality detection unit including the conventional detection circuit will be described.

  Conventionally, the abnormality detection unit includes, for example, capacitors C11 and C12, diodes D11 and D12, and a resistor R11 as shown in the left part of FIG. Here, the capacitor C11 functions as a coupling capacitor. One end of the capacitor C11 is connected to the input terminal Vin, and the other end is connected to the cathode of the diode D11 and the anode of the diode D12. Has been. The cathode of the diode D11 is connected to the other end of the capacitor C11 and the anode of the diode D12, and the anode is grounded. The anode of the diode D12 is connected to the other end of the capacitor C11 and the cathode of the diode D11, and the cathode is connected to one end of the capacitor C12, one end of the resistor R11, and the output terminal Vy. Has been. One end of the capacitor C12 is connected to the cathode of the diode D12, one end of the resistor R12, and the output terminal Vy, and the other end is grounded. One end of the resistor R11 is connected to the cathode of the diode D12, one end of the capacitor C12, and the output terminal Vy, and the other end is grounded. The capacitor C12 and the resistor R11 constitute an integrating circuit. The output terminal Vy is connected to the discrimination circuit 14 in FIG.

  At this time, when Vin (= Vm × Sin (wt)) is input to the input terminal Vin, the capacitor C11 functions as a coupling capacitor, and the output voltage Vy of the output terminal Vy has an invalid DC component. In the band higher than the band f1, the peak potential (Vm−Vd) (Vd is the forward potential of the diode D12) is maintained as shown in the right part of FIG. In the right part of FIG. 3, the horizontal axis is the frequency and the vertical axis is the voltage value.

  In other words, conventionally, the abnormality detection unit only performs peak detection processing in which the peak value of the input voltage is output as it is. As a result, the noise peak value itself is discriminated, which may result in insufficient sensitivity. In particular, when the resonance frequency and the frequency of the AC noise are completely the same, abnormalities such as low-frequency electromagnetic fields are detected. Previously, the game ball detection switch may malfunction. As a countermeasure, a method of reducing the threshold value of the rear-stage discrimination circuit to the limit and preventing minute noise from escaping can be considered, but there is a possibility that the tolerance of other disturbance factors such as electrostatic discharge may be reduced at the same time.

[Operation of Abnormality Detection Unit of the Present Invention]
Next, the abnormality detection operation of the abnormality detection unit 2 in FIG. 1 will be described with reference to FIG.

  First, assuming that there is no operation of the high-frequency oscillation circuit 13, an intermediate potential VLC between the coupling circuit 11 serving as an input to the high-frequency oscillation circuit 13 and the LC resonance circuit 12 will be described.

  When the detection electrode 1 detects an electromagnetic field in the vicinity of a low frequency, a voltage is induced, and the input voltage Vin (= Vm × sin (wt)) is input to the coupling circuit 11, the frequency of the input voltage Vin is sufficiently high. If there is no loss due to the capacitor C1 functioning as a coupling capacitor, the peak value of the intermediate voltage VLC changes as shown by a curve W1 shown in the upper part of FIG. That is, in a low band sufficiently lower than the frequency f11 in FIG. 4, the coil L0 is short-circuited and the capacitor C0 is open, so that the peak value VLC_H of the VLC is a value represented by the following equation (7). Converge.

VLC_H = R0 × Vm / (R0 + R1)
... (7)

  Here, R0 and R1 represent resistance values of the resistors R0 and R1, respectively, and Vm represents a peak value of the input voltage.

  Further, in a high band sufficiently higher than the frequency f13 in FIG. 4, the capacitor C0 is short-circuited, so that it converges to 0 as shown by the equation (8) below the peak value VLC_L of the VLC.

VLC_L = 0
... (8)

  Furthermore, in the intermediate band in the vicinity of the frequency f12 that is the resonance frequency in FIG. 12, the peak of the impedance of the LC resonance circuit 12 is L0 / (R0 × R1) that is the reciprocal of the conductance represented by the equation (3). Become. For this reason, in the vicinity of the resonance frequency, the peak value VLC_R of the intermediate voltage VLC is a value represented by the following equation (9).

VLC_R = (L0 / (R0 × C0)) × Vm / (R1 + L0 / (R0 × C0))
= (L0 × Vm) / ((R1 × R0 × C0) + L0)
... (9)

  As the set values of each circuit, for example, the inductance of the coil L0 is set to 82 μH, the capacitance of the capacitor C0 is set to 270 pF, the resistance value of the resistor R0 is set to 15Ω, and the resistance value of the resistor R1 is set to about 30 kΩ. Then, the peak value VLC_R at the resonance frequency of the VLC is about 2/3 of the peak value Vm.

  That is, the intermediate voltage VLC does not exceed the peak value Vm of the input voltage when the high-frequency oscillation circuit 13 is not operating, but the peak value increases in the vicinity of the resonance frequency.

  Further, the behavior of the intermediate voltage VLC will be described on the premise that the high-frequency oscillation circuit 13 operates.

  When the intermediate voltage VLC that changes due to the voltage induced by the induced electromagnetic wave exceeds the voltage value (Vbe−V0) obtained by subtracting the voltage value of the power source V0 from the base-emitter voltage Vbe of the transistor Tr1, the transistor Tr1 is turned on. It becomes. When the transistor Tr1 is turned on, the transistors Tr2 and Tr3 connected to the current mirror are turned on, and the currents I1 and I2 flow with equal current values. At this time, since the current I2 flows as a positive feedback current, normally, the current I2 flows superimposed on the LC resonance circuit 12 that has been driven only by the current I0 from the constant current source I0. By such an operation, the peak value of the intermediate voltage VLC has a curve W1 in the range of frequencies f11 to f13 where the intermediate voltage VLC exceeds the voltage value (Vbe−V0) as shown by the curve W2 shown in the lower part of FIG. In the vicinity of the resonance frequency, the peak value Vm of the input voltage Vin is exceeded and further increased until the voltage of the power supply Vcc is reached.

  That is, when the detection electrode 1 detects an electromagnetic field in the vicinity of a low frequency and generates an induced voltage, the conductance gL1 of the LC resonance circuit 12 becomes small in the vicinity of the resonance frequency, so that the state of the above-described equation (1) The oscillation operation of the high-frequency oscillation circuit 13 is started by changing from the state to the state of the expression (2). Further, when the intermediate voltage VLC exceeds the voltage value (Vbe−V0), the positive feedback current I2 is superimposed at the position VLC in FIG. 1, so that the peak value of the intermediate voltage VLC stands out in the vicinity of the resonance frequency f12. It changes to become a high value.

  As a result, by setting the threshold value in the discrimination circuit 14 high, it is possible to detect only the frequency band in the vicinity of the resonance frequency f12 with high accuracy. Further, since the game ball detector 5 is also provided with the same high-frequency resonance circuit 112, a low-frequency near electromagnetic field in a band substantially coincident with a band that causes a malfunction in the game ball detector 5 can be reliably and accurately detected. It becomes possible to detect.

  Furthermore, it is desirable that the abnormality detection unit 2 can detect the low-frequency near electromagnetic field before the game ball detection unit 5 is affected by the low-frequency near electromagnetic field. That is, it is desirable that the abnormality detection unit 2 can detect a low-frequency near electromagnetic field with higher sensitivity than the game ball detection unit 5.

  Therefore, adjustment of detection sensitivity of the abnormality detection unit 2 will be described.

  For example, as the resistance value of the resistor R1 of the coupling circuit 11 is adjusted so as to become a larger value, the voltage VLC at the position VLC becomes higher than the curve W1 ′, as shown in the upper part of FIG. The waveform changes to W2 ′, and the waveform decreases as a whole. Conversely, by setting the value of the resistor R1 to a small value, the peak value increases as a whole, and it becomes possible to adjust to a sharp curve.

  Further, as the resistance value of the resistor R0 of the LC resonance circuit 12 is adjusted so as to become a larger value, the voltage VLC at the position VLC is changed to the curve W1 '' as shown in the lower part of FIG. , W2 ″, the skirt portion of the waveform rises and the peak falls, so that the undulation is reduced and the waveform is blunt as a whole. Conversely, by setting the value of the resistor R0 to a small value, the skirt portion is lowered and the peak is raised, so that the undulation is increased as a whole, and a sharp undulation curve can be adjusted.

  That is, for example, by increasing the values of the resistors R0 and R1, it is possible to adjust the detection band of the low-frequency near electromagnetic field and the level of sensitivity in each band. Therefore, for example, the low-frequency near electromagnetic field waveform affecting the game ball detection unit 5 is adjusted to be the curve W2 ″ in the lower part of FIG. 5, and the curve W2 ″ is larger than the curve W2. Thus, by setting a relatively high value as the threshold value, it is possible to detect the low-frequency near electromagnetic field before the game ball detector 5 is affected. In addition, since it is possible to make a determination based on the waveform that is emphasized and increased near the resonance frequency, it is possible to detect a low-frequency near electromagnetic field with high accuracy.

[Abnormality detection processing]
Next, the abnormality detection process will be described with reference to the flowchart of FIG.

  In step S1, the discrimination circuit 14 determines whether or not the amplitude of the oscillation output of the high frequency oscillation circuit 13 is greater than a predetermined value. That is, when the low-frequency near electromagnetic field does not affect the detection electrode 1, no sine wave voltage is induced, so that the resonance action by the LC resonance circuit 12 does not occur, and the high-frequency oscillation circuit 13 does not oscillate. For this reason, since the amplitude of the oscillation output of the high frequency oscillation circuit 13 does not become larger than the predetermined value, the process of step S1 is repeated. At this time, the discrimination circuit 14 is in a state of outputting, for example, a Low signal having the same value as the ground potential to the output circuit 15. As a result, during this time, the output circuit 15 outputs, for example, a Low signal having the same value as the ground potential to the control unit 3 as the signal V1 indicating that the low-frequency near electromagnetic field is not detected.

  On the other hand, in step S1, when a low-frequency near electromagnetic field affects the detection electrode 1, a sinusoidal voltage is induced, so that the resonance action by the LC resonance circuit 12 occurs, so that the high-frequency oscillation circuit 13 Start oscillation output. For this reason, since the amplitude of the oscillation output of the high-frequency oscillation circuit 13 becomes larger than a predetermined value, the process proceeds to step S2.

  In step S2, the discrimination circuit 14 detects an amplitude higher than a predetermined value, and as a signal V1 indicating that a low-frequency near electromagnetic field is detected as an abnormal state, for example, a Hi signal having the same value as the power supply voltage Is supplied to the output circuit 15.

  In step S3, the output circuit 15 outputs, for example, a Hi signal having the same value as the power supply potential as a signal indicating that the low-frequency near electromagnetic field that is in an abnormal state is detected to the control unit 3. .

  In step S11, the control unit 3 determines whether or not the signal V1 indicating that an abnormality has been detected is supplied from the abnormality detection unit 1, and the process is performed until a signal indicating the abnormality is supplied. repeat.

  In step S11, for example, when the signal V1 indicating that the low-frequency near electromagnetic field is detected is supplied by the processing in step S3, in step S12, the control unit 3 All the signals V2 supplied from the game ball detector 5 are fixed to invalid signals. That is, the operation in the game ball detection unit 5 in the state where the low-frequency near electromagnetic field is detected is considered to be an abnormal operation in which the low-frequency near electromagnetic field is generated by a malicious third party, for example. The signal V2 output from the game ball detector 5 during that time is treated as an invalid signal. Alternatively, the control unit 3 can identify that the signals are supplied under the condition that the low-frequency near electromagnetic field is detected in association with the signal V2 output from the game ball detection unit 5. And information that can be confirmed later as a result of detecting the game ball in an abnormal state is recorded.

  In step S13, the control unit 3 controls the reporting unit 3a in FIG. 1, and from the reporting output unit 4 having a display function such as an LCD (Liquid Crystal Display), a voice output function such as a speaker, and the like. Information indicating that a low-frequency near electromagnetic field is detected is presented to the inside of the gaming machine or the outside of the gaming machine by an image or sound.

  Through the above processing, it is possible to detect a low-frequency near electromagnetic field that is highly likely to affect the game ball detection unit 5 at a timing before the game ball detection unit 5 is affected. In addition, if a low-frequency near electromagnetic field is detected, it is reported that an abnormality has occurred due to the low-frequency near electromagnetic field, and it may or may be affected by the low-frequency near electromagnetic field in the future. It is possible to take measures such as recording that the detection result of the game ball of the gaming ball detection unit 5 having a high reliability is a detection result with low reliability, or ignoring the detection result, in the vicinity of the low frequency It is possible to suppress fraudulent acts using electromagnetic fields.

<2. Second Embodiment>
In the above description, an example has been described in which an ornamental part on which an annular metal plating is applied in a pachinko gaming machine is assumed as the detection electrode 1. For example, as shown in FIG. 7, the connection terminal 41 may be connected to the launch rail 31 of the game ball so that the launch rail 31 itself can be used as an antenna.

  For example, in the case of the pachinko gaming machine 51 shown in FIG. 8, the firing rail 31 is a metal rail that is provided on the board surface and sends out a game ball launched from the launching device to the game board surface.

  By configuring the detection electrode 1 from such a metal part having an annular structure of the pachinko gaming machine 51, for example, as shown in the upper right part and the lower part of FIG. Since the front range Z1-1 and the rear range Z1-2 are detection ranges of low-frequency near electromagnetic fields, a suitable configuration can be used to monitor fraudulent acts by an unauthorized player. It is possible to monitor fraudulent activities. In FIG. 9, the upper left part is a front view of the pachinko gaming machine 51, the upper right part is a side view, and the lower part is a front perspective view.

  In addition, for example, as shown in the upper left part of FIG. 9 and FIG. 8, an outer rail 61 that surrounds the outer periphery of the game board surface may be used. Further, the pachinko gaming machine as a whole is a U-shape. It may be a frame ground 64 surrounded by. Further, hinges 62 and 63 that are connected (electrically connected) to the frame ground 64 by metal parts may be used.

  However, since the frame ground 64 plays a role such as electrostatic discharge, if it is configured to be directly grounded, the detection sensitivity of the low-frequency near electromagnetic field may be excessively lowered. Therefore, in order to handle the frame ground 64 in the same manner as the detection electrode 1, in a normal state, the frame ground 64 is insulated from the ground plane, and is discharged to the ground plane only when an overvoltage such as static electricity occurs. It is necessary to ground through a surge protection circuit such as a discharge gap or surge absorber.

  As shown in FIG. 10, the connection terminal 41 can be easily retrofitted to an existing pachinko gaming machine by connecting to various detection electrodes 1. .

  That is, as shown in the upper right part of FIG. 10, one end of the connection terminal 41 is connected to the substrate portion of the abnormality detection unit 2, and the other end is connected to the upper left part of FIG. 10. As shown in the figure, a screw hole is provided, and the connection terminal 41 is electrically connected by being screwed to the detection electrode 1.

  10, one end of the connection terminal 41 ′ is connected to the substrate portion of the abnormality detection unit 2 as in the upper part of FIG. 10 and the other end is connected. As shown in the middle left part of FIG. 10, the terminal has a snap terminal structure, and is electrically connected by being connected so as to sandwich the flat detection electrode 1.

  Further, as shown in the lower right diagram of FIG. 10, one end of the connection terminal 41 ″ is connected to the substrate portion of the abnormality detection unit 2 as in the upper portion of FIG. As shown in the lower left part of FIG. 10, the part has a spring terminal structure, and is electrically sandwiched between the curved launch rail 31 and the wall surface 201 by the repulsive force of the spring terminal. Connected to.

  Any of the connection terminals 41, 41 ′, 41 ″ can be easily connected to a metal part of a pachinko gaming machine, and particularly easily and surely connected to an existing pachinko gaming machine. It becomes possible. As a result, it is possible to easily and reliably detect the arrival of an electromagnetic field in the vicinity of a low frequency, not only for a new pachinko machine but also for an existing pachinko machine.

  As described above, according to the present invention, the low-frequency near electromagnetic field can be detected by the low-frequency near electromagnetic field generated in the pachinko gaming machine at a timing before the malfunction of the game ball detection switch occurs. It is possible to appropriately monitor the low-frequency near electromagnetic field and to appropriately suppress the functional failure of the game ball detection switch.

  In this specification, the processing of each step constituting the flowchart is not limited to the processing performed in time series in the order described, but of course, it is not necessarily performed in time series, either in parallel or individually. This includes processing to be executed.

DESCRIPTION OF SYMBOLS 1 Detection electrode 2 Abnormality detection part 3 Control part 4 Notification output part 5 Game ball detection part 11 Coupling circuit 12 LC resonance circuit 13 High frequency oscillation circuit 14 Discrimination circuit 15 Output circuit L0 Coil C0, C1 Capacitor R0, R1 Resistance

Claims (11)

A low-frequency near electromagnetic field detection circuit that is mounted on a pachinko gaming machine and detects a low-frequency near electromagnetic field irradiated from the outside of the pachinko gaming machine,
A detection electrode for detecting an induced voltage generated by the low-frequency near electromagnetic field;
A coupling circuit that is connected in series with the detection electrode and adjusts the crest or level of the induced voltage generated in the detection electrode;
A band adjusting circuit that is arranged between the coupling circuit and a ground potential and sets a detection allowable frequency of the induced voltage;
A current feedback type high-frequency oscillation circuit that oscillates a high-frequency sine wave by the voltage output from the band adjustment circuit,
The high frequency oscillation circuit includes:
When the low-frequency near electromagnetic field is not irradiated to the detection electrode, the negative conductance is set to stop oscillation,
A low-frequency near electromagnetic field detection circuit in which the high-frequency oscillation circuit changes to an oscillation state when the low-frequency near electromagnetic field is irradiated to the detection electrode. The band adjustment circuit includes an LC resonance circuit,
The low-frequency near electromagnetic field detection circuit according to claim 1, wherein when the detection electrode is irradiated with the low-frequency near electromagnetic field, only the frequency band near the resonance frequency of the LC resonance circuit is detected. The coupling circuit includes a series circuit of a resistor and a capacitor;
The low-frequency near electromagnetic field detection circuit according to claim 1, wherein a detection sensitivity of the resistor is set by changing a resistance value thereof. The low-frequency near electromagnetic field detection circuit according to claim 1, wherein the detection electrode includes a metal member installed in the pachinko gaming machine or a structure plated with metal. The low-frequency near electromagnetic field detection circuit according to claim 1, wherein the detection electrode has an annular structure surrounding a board surface of the pachinko gaming machine. A low-frequency near electromagnetic field detection sensor that is mounted on the pachinko gaming machine and detects a low-frequency near electromagnetic field irradiated from the outside of the pachinko gaming machine,
A low-frequency near electromagnetic field detection circuit according to any one of claims 1 to 5,
A comparison circuit for discriminating the output potential of the low-frequency near electromagnetic field detection circuit;
A low-frequency near electromagnetic field detection sensor comprising: an output circuit that outputs a detection signal based on the state of the comparison circuit. The low-frequency near electromagnetic wave according to claim 6, further comprising a detection electrode connection terminal that connects the low-frequency electromagnetic field detection sensor and a metal member installed in the pachinko gaming machine or a structure plated with metal. Field detection sensor. A gaming machine in which the detection electrode connection terminal of the low-frequency near electromagnetic field detection sensor according to claim 7 is installed on a launch rail. The gaming machine according to claim 7, wherein the low-frequency near electromagnetic field detection sensor is installed on a frame ground, and the frame ground is opened or grounded via a surge protection element. A gaming machine equipped with the low-frequency near electromagnetic field detection circuit according to claim 1 or the low-frequency near electromagnetic field detection sensor according to claim 6,
When the low-frequency near electromagnetic field detection circuit or the low-frequency near electromagnetic field detection sensor detects a low-frequency near electromagnetic field, the detection judgment result is notified to the inside of the gaming machine or outside the gaming machine based on the output signal. A gaming machine further comprising a notification means for performing. A game including the low-frequency near electromagnetic field detection circuit according to any one of claims 2 to 5, or the low-frequency near electromagnetic field detection sensor according to any one of claims 6 to 7, and a proximity switch that detects a game ball. Machine,
The resonance frequency of the LC resonance circuit is set in the vicinity of the oscillation frequency of the proximity switch.

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