JP2000324300A - Magneto-optical compound head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a magneto-optical compound head which is small and is capable of freely select the luminescent color of an optical head. SOLUTION: This magneto-optical compound head 20 houses a magnetic head 23 and an optical head 24 in a case 21 and inspects the same place of an object to be inspected. In this case, in a yoke 25 of the head 23, the point of a yoke 26, whose both ends are wide open and forms an almost C shape faces to the point of a flat yoke 27 with a slight gap δ inbetween, the respective base ends abut on each other, are connected magnetically and are formed, and the gap δis also arranged at the center position of a front 21a which abuts on the object to be inspected of the case 21. In the head 24, optical sensors 32 and 33 are arranged adjacent to the yoke 27, and a sensor part is arranged in the case 21, while facing the object to be inspected through a window 21c provided side by side adjacent to the gap δ of the head 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combined optical / magnetic head, and more particularly to a combined optical / magnetic head suitable for inspecting bills, securities, and the like as objects to be inspected.

[0002]

2. Description of the Related Art In recent years, vending machines have become widespread, and the frequency of use of banknotes has become extremely high. Along with this, it is necessary to reliably inspect bills. Inspection of banknotes is generally performed optically and magnetically.
That is, in recent years, magnetic ink has been adopted for printing banknotes, and a print pattern at a specific portion of the banknote is magnetically detected by a magnetic head and optically detected to determine whether the banknote is authentic. .

FIG. 5 shows an example of a conventional combined optical / magnetic head. The optical / magnetic combined head 1 has a case 2 in which a magnetic sensor 3 and an optical sensor 4 are housed, and is molded with a resin member 5 to form a package. Magnetic head 3
Is composed of a yoke 6, an excitation coil 7, a detection coil 8, and the like. The tips of the left and right yokes 6a and 6b are opposed to each other with a slight gap g. Optical head 4
Is composed of a light emitting element 10, a light receiving element 11, light guides 12, 13, and the like. One end of each of the light guides 12 and 13 is
The other end is connected to the light emitting element 10 and the light receiving element 11, respectively. The other end is connected to the light transmitting body 14 inserted through the hole 6c provided at the base end of the yoke 6 and inserted into the gap g at the tip end. I have. The gap g of the yoke 6 serves as a window for detecting the optical head 4.

The magnetic head 3 magnetically detects a magnetic ink print pattern of a banknote to be inspected. Light emitted from the light emitting element 10 is transmitted through the light guide 12 and the light transmitting body 14.
And the reflected light is incident on the light receiving element 11 through the light transmitting body 14 and the light guiding body 13. Thereby, the print pattern is optically detected. Then, the print pattern of the same line is simultaneously detected by the magnetic head 3 and the optical head 4.

[0005]

In the conventional optical / magnetic combined head 1 described above, the gap g of the magnetic head 3 is severely abraded due to the sliding of bills, and the light transmitting member 14 is made of non-magnetic material. Sapphire glass or the like that has high wear resistance is used. Therefore, the cost of the head increases.

The magnetic head 3 preferably has a smaller gap g in order to enhance the detection sensitivity.
It is preferable that the gap g, that is, the detection window be wider, because more light can be taken and the detection sensitivity is increased. For this reason, in the combined optical / magnetic head 1 having the above structure, the gap g must be widened in order to increase the detection sensitivity of the optical head 4, and the detection accuracy of the magnetic head 3 is sacrificed.
Further, since the optical head 4 is disposed behind the magnetic head 3, there is a problem that the head becomes large.

[0007] Banknotes and the like are printed with inks of various colors, and light emitting elements that emit light of various colors have recently been provided. Therefore, when the print pattern is optically detected, it is preferable that the print pattern can be detected by various colors, infrared rays, or the like. However, the optical fibers used as the light guides 12 and 13 of the optical head 4 are:
Since the light-guiding characteristics differ depending on the color, the color of the light to be used is limited, and the light-emitting element of the optical head 4 cannot be freely selected, resulting in a problem of poor versatility.

In order to cope with such a problem, the magnetic head 3 and the optical head 4 are separated from each other as shown in FIG. There is also. According to this configuration, it is possible to dispose the optical head 4 apart from the bill M, so that a light guide is not required, and light emitting elements of various colors can be used.

However, in the above configuration, it is difficult not only to arrange the magnetic head 3 and the optical head 4 on the same line, but also to use the pressing rubber roller 15 for pressing the bill M against the magnetic head 3. There is a problem that the detection accuracy of the optical head 4 tends to vary because the optical head 4 swings up and down as shown by the dotted line as the distance from the optical head 4 increases.
In addition, the optical head 4 is susceptible to ambient light and has a problem that its characteristics become unstable.

The present invention has been made in view of the above points, and has as its object to provide a compact optical / magnetic head capable of freely selecting the emission color of an optical head.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, a magnetic head and an optical head are housed in one case, and an optical / magnetic composite for inspecting the same portion of an object to be inspected. A yoke of the magnetic head, wherein a tip of a substantially y-shaped first yoke having both ends largely opened and a tip of a substantially flat second yoke are opposed to each other with a slight gap. The base ends are in contact with and magnetically connected to each other, and the gap is disposed at a center position of a front surface of the case in contact with an object to be inspected; And a sensor unit is disposed facing the object to be inspected through a window juxtaposed in proximity to the gap of the magnetic head in the case. .

According to a second aspect of the present invention, the window facing the sensor section of the optical sensor is -R / 3 of the radius of the front face of the case from the center of the case back and forth in the transport direction of the object to be inspected. ＲR / 5. In the combined optical / magnetic head, the magnetic head and the optical head are housed side by side in one case, and are arranged on the same detection line, so that the same portion of the inspection target can be detected. . Thereby, the inspection accuracy is improved. In the optical head, it is possible to select an optical sensor of light most suitable for the object to be inspected because the optical sensor portion directly faces the object to be inspected through the window of the case.

The window for the optical head provided in the case is
By providing the magnetic head in the range of -R / 3 to R / 5 of the radius of the front surface of the case from the position of the gap of the magnetic head disposed at the center position of the case in the front-rear direction with respect to the transport direction of the inspection target, Adhesion and accumulation of dust generated from the inspection target at the time of inspection can be prevented, and a decrease in the detection accuracy of the optical head can be prevented.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a combined optical / magnetic head according to the present invention, and FIG. 2 is a front view of FIG. As shown in FIGS. 1 and 2, the combined optical / magnetic head 20 includes a case 21 in which a magnetic head 23 and an optical head 24 are integrally housed, and is molded with a resin member 22 and packaged. The magnetic head 23 includes a yoke 25 and a coil 28.
Consists of The yoke 25 of the magnetic head 23 has a substantially C-shape that is asymmetrical in a plan view and is bilaterally asymmetrical.
Shaped first yoke 26 and flat plate-shaped second yoke 2
7.

The distal end 26a of the yoke 26 has its end face facing the inner surface of the distal end 27a of the yoke 27 with a slight gap δ, and the end face of the proximal end 26b has the proximal end 27b of the yoke 27.
A coil 28 composed of an excitation coil and a detection coil is wound around the base end 26b. The yoke 27 has a tip 27a.
May be slightly L-shaped toward the tip 26a of the yoke 26, but it is better to make the yoke 2 flat as in the embodiment.
6 is formed between the yoke 2 and the tip 26a of the yoke 2.
7, the yoke 25 can be formed in a flat C-shape, and the optical head 24 can be disposed close to the gap δ of the magnetic head 23, which is preferable.

In the magnetic head 23, the gap δ is located at the center of the front surface 21a of the case 21 in contact with the object to be inspected, the plate-shaped yoke 27 is located at the center, and the substantially C-shaped yoke 26 is located at one position from the center. It is arranged shifted to the side. That is, the magnetic head 23 is disposed in the case 21 so as to be biased to one side. The ends of the yokes 26 and 27 are connected to windows 21 b provided on the front surface 21 a of the case 21.
And is flush with the front surface 21 a of the case 21. The front surface 21a of the case 21 is a curved surface having a predetermined radius R. The radius R is set so that the object to be inspected can be taken in or returned smoothly. The gap δ of the yoke 25 is filled with a non-magnetic member 30 such as glass to prevent dust.

The optical head 24 includes a light emitting element 32 and a light receiving element 33 as optical sensors. The light emitting element 32 and the light receiving element 33 are arranged near the center of the case 21 and the yoke 2
7 are arranged adjacent to the outer side surface in the width direction thereof (FIG. 2). A slit-shaped window 21 c is provided on the front surface 21 a of the case 21 along with the window 21 b of the magnetic head 23. The light-emitting portion of the light-emitting element 32 and the light-receiving portion of the light-receiving element 33 are provided on the molding material 22. It faces the outside of the case through the light path 22a and the window 21c. Optical head 24
The window 21c and the light path 22a are filled with a transparent glass 35 for dust prevention. The glass 35 has substantially the same light guiding characteristics for light of various colors. The light emitted from the light emitting unit as the sensor unit of the light emitting element 32 is applied to the surface to be inspected through the glass 35, and the reflected light is incident on the light receiving unit as the sensor unit of the light receiving element 33 through the glass 35. You. Since the dust-proof glass 35 has substantially the same light-guiding characteristics for light of various colors, light-emitting elements of various colors can be used as the light-emitting elements 32.

As shown in FIG. 3, the bill M to be inspected includes the glass 30 having the gap δ of the magnetic head 23 of the combined optical / magnetic head 20 and the front face 2 of the case 21.
When the pressing roller 1a is pressed by the pressing rubber roller 40, the surface thereof is worn and fine adhesive dust (dust) made of printing ink, paper, or the like is generated. In the case 21, the front surface 21a is a curved surface having a predetermined radius R, and the portion of the gap δ is located at the apex position (center position) of the case 21 and receives a cleaning action by the bill M. Therefore, the dust is prevented from adhering to the portion of the gap δ, but the dust adheres to the position away from the portion of the gap δ since the dust is not affected by the cleaning action by the bill M.
Becomes In particular, a large amount of paper money M accumulates on the transport direction side indicated by the arrow. Therefore, in the combined optical / magnetic head 20,
The window 21c of the optical head 24 of the case 21 is preferably provided at a position where the dust 42 does not easily adhere.

Therefore, in the present invention, the radius R of the front surface 21a (inspection surface) of the case 21 is set to 10 mm and 20 mm for the preferable position of the window 21c for the optical head 24 of the case 21.
In the case of mm, the degree of dust accumulation for each of these radii R was examined. The result is shown in FIG. 4, the horizontal axis indicates the distance from the center position of the front surface 21a of the case 21, that is, the center position of the gap δ of the magnetic head 23, and the vertical axis indicates the accumulation amount of the dust. Then, the deposition amount when the radius R is 10 mm is shown by a solid line, and the radius R is 2 mm.
The case of 0 mm is indicated by a broken line. In the horizontal axis, the distance from the center to the right side is expressed as positive with respect to the gap δ as the carry-out direction of the bill M, and the left side is expressed with respect to the gap δ as negative as the carry-in direction of the bill M.

As can be seen from FIG. 4, the range in which dust does not adhere is, when the radius R is 10 mm, before and after the center.
3 mm to +2 mm (-R / 3 to R / 5), radius R is 2
In the case of 0 mm, -3.5 mm to +4.5 mm (-R / 6 to R /
5). It is desired that the combined optical / magnetic head 20 be miniaturized. Therefore, when the width of the case 21 is about 10 mm, the radius R is appropriately about 10 mm. In this case, the window 21c is positioned between −3 mm and +2 mm (−R / 3) before and after the center of the case 21. To R / 5). The dead zone d due to the gap δ (about 0.3 mm) of the magnetic head 23 and the plate thickness t (about 0.8 mm) of the yoke 27 falls within the range of -3 mm to +2 mm.
(= (Δ + t) / 2) (approximately 0.95 mm). In this case, the combined optical / magnetic head 20 is arranged such that the optical head 24 is switched upstream and downstream with respect to the transport direction of the banknote M (in FIG. Therefore, the dead zone d may be determined in consideration of the gap δ and the thickness of the yoke 27.

Therefore, the window 2 of the optical head 24 of the case 21
1c can be extremely effectively prevented from adhering the dust by being provided within the above-mentioned range from the center position of the case 21, and accordingly, maintenance of the window 21c of the optical head 24 can be largely omitted. Can be. The operation will be described below.

As shown in FIG. 3, the bill M is conveyed in the direction of the arrow and is pressed against the gap δ of the combined optical / magnetic head 20 by the pressing rubber roller 40. And
The magnetic head 23 (FIG. 1) magnetically detects the print pattern at the position. The optical head 24 optically detects the print pattern detected by the magnetic head 23. Thereby, the magnetic head 23 and the optical head 24 can detect the same portion of the print pattern of the bill M.

Since the optical head 24 is provided close to the magnetic head 23 and is disposed near the pressing roller 45, the flapping of the bill M is small, the detection signal is stabilized, and the detection accuracy is improved. Further, as the light emitting elements of the optical head 24, light emitting elements of various colors can be used, and it is possible to effectively deal with printing inks of various colors.

Further, since the window 21c of the optical head 24 is displaced from the center (gap δ of the magnetic head 23), a light receiving element is arranged in the case 21 and a light emitting element is arranged on the opposite side of the object to be inspected. Thus, it can be used as a transmission type optical sensor. In the above embodiment,
The case where the printed pattern of the banknote is inspected as the object to be inspected by the combined optical / magnetic head 20 has been described. However, the present invention is not limited to this, and it is of course applicable to the inspection of other printed patterns such as securities. It is.

[0025]

As described above, according to the first aspect of the present invention, by housing the optical head and the magnetic head in the same case, it is possible to reduce the size and cost and to reduce the cost. The same line as the object to be inspected can be inspected with the optical head, and the inspection accuracy is improved. In addition, since a light guide for guiding the light of the optical sensor to the optical head is not used, it is possible to use an optical sensor having an optimal color according to an object to be inspected, and to broaden an object to be inspected. Can be. Further, since the position of the optical head is displaced from the gap of the magnetic head, it is possible to configure a transmission type optical sensor.

According to the second aspect of the present invention, it is possible to arrange the optical head at a position where dust is unlikely to adhere and accumulate, thereby improving inspection accuracy and facilitating maintenance.

[Brief description of the drawings]

FIG. 1 is a sectional view of a combined optical / magnetic head according to the present invention.

FIG. 2 is a front view of the combined optical / magnetic head of FIG. 1;

FIG. 3 is an explanatory diagram of adhesion of dust caused by an object to be inspected in the combined optical / magnetic head of FIG. 1;

4 is a diagram showing a relationship between a distance from a center position of the head and an amount of accumulated dust in the combined optical / magnetic head of FIG. 3;

FIG. 5 is a sectional view of a conventional combined optical / magnetic head.

FIG. 6 is an explanatory view of a conventional type in which a magnetic head and an optical head are separated.

[Explanation of symbols]

 Reference Signs List 20 optical / magnetic combined head 21 case 21b, 21c window 23 magnetic head 24 optical head 25 yoke 26 first yoke 27 second yoke 28 coil 30, 35 dustproof glass 32 light emitting element 33 light receiving element 40 pressing rubber roller M banknote ( Inspection target)

Claims (2)

[Claims] 1. A combined optical / magnetic head in which a magnetic head and an optical head are housed in one case and inspects the same portion of an object to be inspected, wherein a yoke of the magnetic head has a substantially open end at both ends. The tip of the C-shaped first yoke and the tip of the substantially flat second yoke face each other with a slight gap therebetween, and are formed such that their base ends abut and are magnetically connected, and The gap is disposed at a center position of a front surface of the case that abuts on an object to be inspected; the optical head includes an optical sensor disposed adjacent to a second yoke of the magnetic head; The optical / magnetic combined head is arranged so as to face the object to be inspected through a window juxtaposed close to a gap of the magnetic head. 2. A window facing a sensor unit of the optical sensor, wherein a radius of a front surface of the case is -R / 3 to R / 5 before and after from a center position of the case to a transport direction of the inspection object.
2. The combined optical / magnetic head according to claim 1, wherein the combined optical / magnetic head is provided in the range of: