JP2008293337A - Coin sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coin sensor, capable of surely detecting even a coin 1 which has no magnetic force or weakened in magnetic force or is demagnetized by providing a magnet 5 (magnetization means) for magnetizing a magnetic body of the coin 1. <P>SOLUTION: In the coin sensor having a coil 4 wound on a core 3 having a coin passage 2 for passing the coin 1 with the magnetic body embedded therein as a space, magnets 5 and 5 are embedded at both ends through the space of the coin passage 2 in the core 3. The magnets 5 and 5 are disposed so as to be opposed to each other with the same polarity. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a coin sensor that determines the type and authenticity of a coin having a magnetic material at least in part.

  In a vending machine or the like, a coin sensor that determines the type and authenticity of a coin often uses a magnetic sensor (see, for example, Patent Document 1). However, since most coins are not magnetic, the conventional coin sensor detects high-frequency AC power to the primary coil and detects eddy current loss of the coin with the secondary coil.

  However, some coins have a magnetic material in part. For example, a 1 euro coin or a 2 euro coin has a three-layer structure in the front and back direction of the inner periphery of the coin, and uses nickel, which is a ferromagnetic material having a weak coercive force, as an intermediate layer. Magnetized (magnetized).

  Such magnetized coins can be detected using a coin sensor as shown in FIG. 5 or FIG. 6, for example. The coin sensor shown in FIGS. 5 and 6 is obtained by winding a coil 4 around a core 3 having a coin passage 2 through which a coin 1 passes as a gap. Here, the coin sensor shown in FIG. 5 is configured such that the coin 1 passes through the coin passage 2 by gravity or the like. On the other hand, the coin sensor shown in FIG. 6 divides the core 3 above the coin passage 2 to dispose a conveyance belt (not shown) between the divided cores 3. The coin 1 passes through the coin passage 2.

  When the magnetized coin 1 passes through the coin passage 2 of the coin sensor, the magnetic lines of force from the coin 1 pass through the core 3 through the gap and interlink with the coil 4. Occurs. Accordingly, the passage of the coin 1 can be detected by measuring the output of the coil 4.

However, the magnetized coin 1 may be demagnetized or demagnetized by applying a strong magnetic field or being exposed to a high temperature during the distribution process. The coin sensor has a problem that it cannot detect the passage of the coin 1 when the magnetic force of the coin 1 is weakened or demagnetized.
Japanese Patent Laid-Open No. 9-115023

  An object of the present invention is to provide a coin sensor capable of reliably detecting even a coin that has no magnetic force, or whose magnetic force has been weakened or demagnetized, by providing a magnetizing means for magnetizing the magnetic substance of the coin.

  The invention of claim 1 is a coin sensor in which a coil is wound around a core having a coin passage through which a coin having a magnetic body passes at least in part as a gap, on the upstream side of the core or the coin passage from the core. Magnetizing means for magnetizing the magnetic body of the coin is provided.

  The invention of claim 2 is a coin sensor in which a coil is wound around a core having a coin passage through which a coin having a magnetic material passes at least in part as a gap. A magnet is embedded.

  According to a third aspect of the present invention, the magnetic body of the coin has a plate shape along the front and back surfaces of the coin, and the coin passage allows the coin to pass in a direction along the front and back surfaces. The magnet embedded in the portion is arranged so that the polarities on the side toward the gap of the coin passage are the same.

  According to the first aspect of the present invention, the magnetic material of the coin is magnetized by the magnetizing means before or when the coin passes through the gap of the core of the coin sensor. An electromotive force is generated. Therefore, if the output of this coil is measured, it can be detected that the coin has passed through the coin passage, and can be used to determine the type and authenticity of the coin. In particular, when the magnetic body of the coin has a sufficient coercive force, the magnetic body is magnetized by the magnetizing means, so that detection is possible even if the magnetizing means and the core are arranged apart from each other.

  According to the invention of claim 2, when the coin passes through the gap of the core of the coin sensor, the magnetic body of the coin is magnetized by the magnetic force of the magnet, so that an electromotive force is generated in the core coil due to electromagnetic induction. Therefore, if the output of this coil is measured, it can be detected that the coin has passed through the coin passage, and can be used to determine the type and authenticity of the coin.

  According to the invention of claim 3, since the polarities of the magnets facing each other across the gap of the core of the coin sensor are the same, the lines of magnetic force from these magnets do not penetrate the front and back surfaces of the coin-like magnetic body of the coin. Without passing through this magnetic body, it passes through a long distance along the front and back surfaces. Therefore, since the magnetic body of the coin is more strongly magnetized by the same magnetic field, the detection accuracy of the coin sensor can be increased.

  The coin detected by the coin sensor of the present invention is not only a coin as a current currency (currency) but also a coin (circular or polygonal flat plate) that circulates only in a specific facility or the like. Well, it is not necessarily limited to those made of metal. And this coin has a magnetic body at least in part. This magnetic body may be exposed on the surface of the coin or may be completely embedded inside. For example, in a 1 euro coin or a 2 euro coin, a nickel intermediate layer, which is a ferromagnetic material having a weak coercive force, is completely embedded inside the outer periphery of the coin and the layers on the front and back sides of the inner periphery. . The coin may be entirely made of a magnetic material. When the magnetic body has a coercive force, the present invention can reliably detect even a coin whose magnetic force has been weakened or demagnetized. Therefore, the magnetic body of the coin is pre-magnetized (magnetized) like a euro coin. It may be that which has not been magnetized in advance.

  The coin sensor of the present invention is obtained by winding a coil around a core (magnetic core). The core is an annular magnetic path formed of a soft magnetic material having a small coercive force. The annular shape of the core is arbitrary, and is not limited to an annular shape, and may be an annular shape with a corner or a twisted shape. Further, the annular shape of the core is not limited to one round, but may be a pair of glasses-like rounds or a combination of more rounds. Furthermore, the cores of multiple turns may be separated from each other, or a part of the cores may be integrated and connected.

  The core is provided with a gap (air gap) in an annular part. This gap becomes a coin passage through which coins pass. The coin normally passes through the coin passage in a direction along the front and back surfaces. In addition, the coin normally passes in a direction in which the gap length direction of the gap coincides with the coin thickness direction. Therefore, in this case, the gap length of the core gap is appropriately longer than the coin thickness.

  The coil is a conductor such as a conducting wire wound around the core, and the conductor does not necessarily have to be wound around the core as long as the conductor is arranged so as to be linked with the magnetic lines passing through the core. This coil can be wound around any position of the core, but the position where the change of the magnetic field lines when the coin passes through the gap can be detected most efficiently, that is, the position where the number of interlinkage of these magnetic field lines changes the most. It is preferable to wind around. The number of coils wound around the core is also arbitrary.

  In the coin sensor of the present invention, the magnetizing means is provided upstream of the core or the coin passage from the core. The magnetizing means is means for magnetizing the magnetic body of the coin, and more specifically, a magnetic field is applied to the coin passing through the coin passage or the coin magnetic body toward the coin passage by being magnetized. . This magnetizing means not only temporarily magnetizes the magnetic material only when a magnetic field is applied, but also in the case of a magnetic material having a coercive force, the magnetic force (residual magnetic flux) is removed even after the external magnetic field is removed. Magnetization by maintaining magnetization can also be performed. However, when the magnetizing means is provided in the core or very close to the upstream side of the core, the magnetizing means only magnetizes the magnetic material temporarily only when a magnetic field is applied. It ’s enough. Of course, whether the magnetizing means magnetizes the magnetic body of the coin depends on the magnitude of the holding force of the magnetic body.

  Examples of such magnetizing means include a coin passing through a coin passage, or a magnet (permanent magnet) or an electromagnet disposed in the vicinity of a coin passing toward the coin passage. These magnets, electromagnets, and the like may be disposed only at one location near the coin, or may be disposed at a plurality of locations. When magnets, electromagnets, etc. are arranged at a plurality of locations, it is preferable to arrange them so as to sandwich a coin. When arranging magnets, electromagnets, etc. so as to sandwich a coin, they may be arranged one by one, or one and a plurality of places, or a plurality of places and a plurality of places. In this case, the magnets, electromagnets, and the like may be disposed so as to be sandwiched between the front and back surfaces of the coin, or may be disposed on both sides or the peripheral side in the direction along the front and back surfaces of the coin. Furthermore, the magnets, electromagnets, and the like arranged so as to sandwich the coin may be arranged so that the polarities on the side facing the coin are different, or may be arranged so that the polarities are the same. Therefore, the magnetic lines of force from these magnets, electromagnets, and the like may penetrate the front and back surfaces of the coin or may pass through the inside along the front and back surfaces of the coin.

  When the magnet, electromagnet or the like is provided in the core, it may be embedded in the core. At this time, it is preferable that a part of the magnet, the electromagnet or the like is exposed to the gap side of the coin passage. In addition, when an electromagnet is used as the magnetizing means, an electromagnet coil wound around the end of the coin sensor core near the gap of the coin passage is used so that the electromagnet core and the coin sensor core can be used together. It may be.

  If the magnetic field is too strong, the magnetic means of the coin may be attracted and cannot pass through the coin passage. Therefore, an appropriate magnetic field is applied. Moreover, if the magnetic field of the magnetizing means is too strong, the magnetic force of the already magnetized coin may be weakened. However, when this magnetizing means is provided on the core of the coin sensor, it is sufficient to apply a sufficiently weak magnetic field. However, when it is provided on the upstream side of the coin path from this core, sufficient magnetization (magnetization) is required. ), It is necessary to apply a strong magnetic field to some extent.

  According to the coin sensor of the present invention, the magnetic material of the coin is magnetized by the magnetizing means before the coin reaches the coin passage or when it passes through the coin passage. Then, since the line of magnetic force passing through the core changes as the coin passes through the gap of the core, an electromotive force is generated in the coil by electromagnetic induction. Therefore, if the output of this coil is measured, it can be detected that the coin has passed through the coin passage, and can be used to determine the type and authenticity of the coin.

  The coil output may be measured, for example, by measuring the coil output voltage. If this terminal voltage is input to a differentiating circuit using an operational amplifier or the like, the change in electromotive force can be measured. In order to determine the type and authenticity of coins, generally, not only the detection result of the coin sensor of the present invention but also the detection results of other types of coin sensors are comprehensively determined.

  An embodiment of the present invention will be described below with reference to FIGS. In these drawings, the same reference numerals are given to constituent members having functions similar to those of the conventional example shown in FIGS.

  As shown in FIG. 1, the coin sensor of this embodiment is one in which coils 4 and 4 are wound around a core 3. The core 3 is a rectangular glasses-shaped two-round structure in which soft magnetic materials are arranged in two horizontal parts arranged vertically and three vertical parts arranged in the left and right. A gap is provided in the part to form a coin passage 2. The coils 4 and 4 are obtained by winding conductive wires around the upper side and the lower side of the vertical part at the center of the left and right sides where the gaps in the core 3 are provided. Although not shown, these coils 4 and 4 are connected in series, and outputs at both ends thereof are connected to a detection circuit composed of a differential circuit using an operational amplifier.

  Magnets 5 and 5 are embedded in the center of the lower end portion of the upper part and the upper end part of the lower part sandwiching the gap in the vertical part at the left and right center of the core 3, respectively. The magnets 5 and 5 are magnetized (magnetized) of a hard magnetic material having a large coercive force. In this embodiment, the magnets 5 and 5 are arranged so that the polarities on the side toward the gap of the coin passage 2 are both N poles. Yes. Further, these magnets 5 and 5 are of a relatively weak magnetic force that does not hinder the movement by strongly attracting the magnetic body of the coin 1 passing through the coin passage 2.

  The coin 1 to be detected by the coin sensor of the present embodiment is a ferromagnetic material having a disk-shaped inner peripheral portion having a three-layer structure in the front and back direction and a disk-shaped intermediate layer having a weak coercive force. One euro coin or two euro coin using some nickel. For both layers on the front and back sides of the outer peripheral portion and inner peripheral portion of the coin 1, an alloy of nickel and copper or brass and not a ferromagnetic material is used. The coin 1 passes through the gap of the core 3 serving as the coin passage 2 by moving from the rear to the front along the front and back surfaces with the front and back surfaces directed in the vertical direction.

  In the coin sensor configured as described above, when the coin 1 does not pass through the coin passage 2, magnetic lines of force are generated only around each magnet 5 as shown in FIG. 2. And the magnetic lines of force from these magnets 5 and 5 hardly link with the coils 4 and 4, and even if there are cases where they are linked, the number of links of these magnetic lines of force does not change. Therefore, no electromotive force is generated at the outputs of the coils 4 and 4.

  Similarly, when another type of coin having no magnetic material passes through the coin passage 2, no electromotive force is generated at the outputs of the coils 4 and 4.

  When the coin 1 passes through the coin passage 2 of the coin sensor, as shown in FIG. 3, a part of the magnetic force lines generated in the vertical direction from the N pole facing the coin passage 2 side of the magnets 5 and 5 reach the coin 1, The coin 1 branches to the left and right within the plate-like magnetic body and returns from the left and right vertical portions of the core 3 to the S pole via the upper horizontal portion and the left and right central vertical portions. Then, the magnetic field lines are linked to the coils 4 and 4, and an electromotive force is generated in the coils 4 and 4 only when the coin 1 passes through the coin path 2. In addition, since the magnetic lines of force from the magnets 5 and 5 pass through the magnetic body of the coin 1 in the horizontal direction over a long distance and are strongly magnetized, the number of linkages with the coils 4 and 4 increases. Therefore, if the output voltage of these coils 4 and 4 is differentiated by a differentiation circuit, a detection signal indicating a change in electromotive force can be obtained with certainty.

  Further, when the magnetic body of the coin 1 is preliminarily magnetized, the lines of magnetic force from the magnetic body are also applied, so the upper coil 4 and the lower coil 4 are asymmetrical, but the coil 4 is the same as described above. , 4 change the magnetic lines of force and generate an electromotive force. The electromotive force generated by the magnetic lines of force from the magnets 5 and 5 and the electromotive force generated by the magnetic lines of force from the magnetic body of the coin 1 are either up or down depending on whether the coin 1 passing through the coin passage 2 is face up or face down. The coil 4 is reversed. For this reason, in order to prevent the electromotive force in these coils 4 and 4 from being canceled by the series connection, each coil 4 may be connected to a detection circuit.

  FIG. 4 shows an embodiment in which the present invention is applied to a conventional coin sensor using the conveyor belt shown in FIG. The core 3 of this embodiment is divided into an upper horizontal portion and an upper portion of a central vertical portion in the left and right directions, and coils 4 and 4 are wound around the upper portions of the divided vertical portions. The magnets 5 and 5 are embedded in each. Also in this coin sensor, only when the coin 1 passes through the coin passage 2, the magnetic lines of force from the magnets 5.

  In the above-described embodiment, the case where the polarity of all the magnets 5 on the coin path 2 side is the N pole has been described, but the same effect can be obtained even when this polarity is the S pole. Further, for example, even when the upper magnet 5 and the lower magnet 5 have different polarities on the coin path 2 side, the lines of magnetic force penetrate the front and back surfaces of the coin 1 and link to the coil 4 to generate electromotive force. As a result, the same detection as in the above-described embodiment is possible. However, in this case, since the magnetic lines of force only penetrate the front and back surfaces of the thin disk-shaped magnetic body of the coin 1, the magnetization is insufficient and the detection accuracy may be reduced to some extent.

  Further, in the case of the above embodiment, the detection can be performed only by temporarily magnetizing the magnet 5 only when a magnetic field is applied without magnetizing the magnetic body of the coin 1. When the magnet 5 is not embedded in the core 3 but is arranged away from the upstream side of the coin passage 2, it is necessary to magnetize the magnetic body of the coin 1.

1 is a perspective view of a coin sensor according to an embodiment of the present invention. 1 is a front view of a coin sensor according to an embodiment of the present invention, in which no coin passes. 1 is a front view of a coin sensor showing a coin passing through an embodiment of the present invention. 1 is a front view of a coin sensor using a transport belt through which coins pass, showing an embodiment of the present invention. It is a perspective view of a coin sensor, showing a conventional example. It is a perspective view of the coin sensor which shows a prior art example and used the conveyance belt.

Explanation of symbols

1 Coin 2 Coin passage 3 Core 4 Coil 5 Magnet

Claims (3)

In a coin sensor in which a coil is wound around a core having a gap as a coin passage through which a coin having a magnetic material passes at least in part,
A coin sensor characterized in that a magnetizing means for magnetizing a magnetic body of a coin is provided upstream of the core or the coin path from the core. In a coin sensor in which a coil is wound around a core having a gap as a coin passage through which a coin having a magnetic material passes at least in part,
A coin sensor characterized in that magnets are embedded in both ends of the core through the gap of the coin passage.   The magnetic body of the coin has a plate shape along the front and back surfaces of the coin, the coin passage allows the coin to pass in a direction along the front and back surfaces, and magnets embedded in both ends of the core The coin sensor according to claim 2, wherein the coin sensor is disposed so that the polarities on the side toward the gap of the coin passage are the same.

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