JPH11238156A - Sensor for surface shape detection and manufacture therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the manufacturing method of a highly accurate sensor for surface shape detection that detects the recessed and projected shape of the entire surface of an object to be measured without direct contact by relatively moving the object to be measured and a detection means only one time. SOLUTION: On one common base 2, the tips of many bar-shaped cores 3 separately arrayed with a prescribed interval are arranged so as to be on the same plane. Also, the tips of many bar-shaped cores 3 are set to face the surface of the metallic object 10 to be measured with recessed and projected parts in a magnetic field relatively movably in a direction orthogonal to an array direction. The detection means 5 for detecting a magnetic flux change due to the recessed and projected shape of the object 10 to be measured is provided on the respective bar-shaped cores 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface shape detecting sensor for detecting irregularities on the surface of an object to be measured in a non-contact manner based on a change in magnetic flux. More specifically, the present invention relates to a surface shape detection sensor capable of detecting the uneven shape of the surface of a measured object within a predetermined range only by relatively moving the measured object once.

[0002]

2. Description of the Related Art Conventionally, there is a dial gauge that can accurately measure the uneven shape of the surface of an object to be measured and has a simple and inexpensive structure. However, since the dial gauge measures the object by fixing the object to be measured and bringing the probe into contact with the uneven surface, the measurement takes a long time. For this reason, it is difficult to instantaneously detect the unevenness of the entire surface of the object to be measured, and the method cannot be applied to the use of detecting the unevenness of the surface of the moving object one after another. That is, there has been no device which has a simple and inexpensive structure and which can successively non-contactly detect the unevenness of the surface of the object to be measured only by relatively moving the object once.

[0003] As described above, there has been no device that has a simple structure and is inexpensive and can successively detect irregularities on the surface of the object to be measured in a non-contact manner. An identification device or the like includes a plurality of sensors to collect various types of data on inserted coins and determine the type and authenticity of coins. Here, there is an eddy current sensor as one of the sensors installed in the coin identification device. The eddy current sensor is installed to face the coin passage, and electrically detects a change in magnetic flux when the coin passes. That is, since the resistivity differs depending on the material and thickness of the coin, the eddy current loss differs for each coin. The eddy current sensor electrically detects the change of the magnetic flux due to the eddy current loss and outputs it. Therefore, the coin identification device determines the material, thickness, diameter, etc. of the inserted coin based on the change in the detection output of the eddy current sensor, and also determines data based on the detection output of other sensors. By comparing these results with data stored in advance, the type and authenticity of the inserted coin are determined.

[0004]

However, in recent years,
There has been a demand for the development of an inexpensive surface shape detection device that can detect the uneven shape of the surface of the object to be measured in a non-contact manner by a single relative movement, and has a simple structure and a low cost. For example, with regard to sensors for coin identification incorporated in vending machines, etc., in the present situation where forgery and forgery of coins are becoming more and more sophisticated, coins are based on the complicated and fine irregularities attached to the surface of coins. There is a request to determine the type and authenticity.

Here, as a method for detecting the unevenness of the surface in a non-contact manner, a method of processing an image taken by a CCD camera or a method of irradiating a semiconductor laser onto the uneven surface and capturing the reflected light by a photodiode or the like. There are methods. However, in the method of capturing an image with a CCD camera, the uneven shape is processed as two-dimensional image data. For example, a fake coin on which a photograph of a real coin is stuck cannot be distinguished. When light is irradiated at a shallow angle from the periphery to make it easy to obtain the unevenness information, if the center is concave, it is difficult to obtain reflected light, and there is a danger that the light will be shaded and there will be a hole. In the method of capturing the reflected light of the semiconductor laser with a photodiode or the like, it is necessary to scan a laser beam in a plane. In addition, in both of these methods, rust and dirt on the uneven surface are indiscriminately hampered identification, and expensive devices dedicated to the uneven shape are separately installed to detect the uneven shape on the coin surface. This leads to an increase in manufacturing cost and an increase in the size of the apparatus, which is not appropriate. Therefore,
In the coin identification device, etc., the existing sensor for detecting the material etc., which has been conventionally provided, is developed to enable the detection of the uneven shape of the coin surface, and the data on the uneven shape of the coin surface together with the data of the coin material etc. It is convenient if we can obtain

The development of such a surface shape detection sensor is required not only for coin identification but also for other applications.

According to the present invention, the uneven shape of the surface of the object can be detected in a non-contact manner, and the unevenness of the entire surface of the object can be detected by a single relative movement between the object and the detecting means. It is an object of the present invention to provide a surface shape detection sensor capable of performing the method, and also to provide a method of manufacturing the surface shape detection sensor with high accuracy.

[0008]

In order to achieve the above object, in the surface shape detecting sensor according to the present invention, a large number of rod-shaped cores are arranged on a single common base at predetermined intervals. The tips are arranged so that the tips are on the same plane, and the tips of a large number of rod-shaped cores are opposed to the surface of a metal object with irregularities in a magnetic field so as to be relatively movable in a direction orthogonal to the arrangement direction, and the rod-shaped Each of the cores is provided with a detecting means for detecting a magnetic flux that changes due to the uneven shape of the object to be measured.

In this case, a line sensor is formed by arranging the detecting means in a line, and a magnetic flux is generated from the tip of each of the rod-shaped cores arranged in a line apart from each other to form a magnetic field. When the device under test moves relative to the line sensor and passes through the magnetic field, the magnetic flux changes due to the unevenness of the surface of the device under test. Is detected. In addition, since the detection means constitutes a line sensor having a length that can include the width of the object, the unevenness of the object can be detected over the entire surface by performing a single relative movement.

Further, in the surface shape detecting sensor according to the present invention, the widths of the tips in the relative movement direction of the plurality of rod-shaped cores are set to be the same width smaller than the width of the concavo-convex shape to be detected. Since the detecting means detects a change in magnetic flux at the tip of the rod-shaped core, the resolution as a sensor is determined by the thinness of the tip of the rod-shaped core. That is, the resolution is improved by making the width of the tip of the rod-shaped core in the relative movement direction smaller than the width of the concavo-convex shape to be detected, and the change in magnetic flux can be detected finely electrically. Therefore, the change pattern of the concavo-convex shape is composed of fine waveforms, and a feature proportional to the surface shape of the measured object is grasped as data represented as a pattern graphic. In addition, in the surface shape detecting sensor according to the present invention, the detecting means is a detection coil wound around the rod-shaped core or a magnetoresistive element attached to the rod-shaped core. Therefore, the magnetic flux that changes due to the surface of the object to be measured is electrically detected by changing the current of the detection coil or by changing the internal resistance of the magnetoresistive element.

Further, in the surface shape detecting sensor according to the third aspect, an auxiliary core for forming a magnetic flux path having the same width as the rod-shaped core in the relative movement direction is provided on both sides of the rod-shaped core in the relative movement direction. The same number of cores as the core are formed integrally, and a separation groove having the same width is formed between the rod-shaped core and the auxiliary core. Therefore, the path of the magnetic flux generated from the tip of the rod-shaped core is secured, the accuracy is improved, and the sensitivity as the sensor for detecting the surface shape is improved.

In the surface shape detecting sensor according to the present invention, a step for mounting an exciting coil to which a high-frequency signal is applied is formed on both sides in the relative movement direction of the auxiliary core, while the rod-shaped core is formed. A separating groove having a groove depth greater than that of the separating groove and the step for mounting the exciting coil is formed between them. Therefore, the excitation coil is wound around the auxiliary core, and the distance from the detection coil is ensured, so that the sensitivity as a sensor is improved. Further, when the distance between the bottom of the separation groove and the stepped portion from the tip of the rod-shaped core is made different, the detection coil and the exciting coil are formed stepwise from each other.

According to a fifth aspect of the present invention, there is provided a method for manufacturing a sensor for detecting a surface shape, in which a plurality of rod-shaped cores arranged at a predetermined interval in a row are arranged on the same plane in one block. A groove having a predetermined width is formed in the arrangement direction, and a separation groove for separating a large number of rod-shaped cores is formed in a direction orthogonal to the groove processing, and a separation groove formed between the rod-shaped cores. Is formed so as to have a groove width that allows a coil to be arranged in each of the rod-shaped cores, and at least one of the detection coil or the excitation coil is formed on the rod-shaped core in a state where a large number of rod-shaped cores are formed in one block. One is to be attached. In this case, since many rod-shaped cores are integrally formed so as to be cut out from a single block such as a ferrite block, it is easy to obtain accuracy at the time of molding, and it is possible to form a highly accurate surface shape detection sensor. And

According to a sixth aspect of the present invention, in the method of manufacturing a surface shape detecting sensor, the same number of auxiliary cores for forming magnetic flux passages are formed on both sides of a large number of rod-shaped cores. Therefore, the passage of the magnetic flux generated from the core tip is secured, and the accuracy as the surface shape detection sensor is improved. In addition, since the separation groove formed between the rod-shaped cores is formed to have a width that allows the detection coil and the excitation coil to be arranged, the detection coil and the excitation coil are provided in each rod-shaped core. Can be wound.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on the best mode shown in the drawings.

FIGS. 1 to 5 show an embodiment of a surface shape detecting sensor 1 to which the present invention is applied. As shown in FIG. 1, the surface shape detecting sensor 1 includes a plurality of rod-shaped cores 3 arranged on a single common base 2 and an object 10 to be measured.
And relative movement, and detects a magnetic flux change in each of the rod-shaped cores 3 to detect the surface shape of the DUT 10. In this case, the rod-shaped cores 3 are spaced and arranged at predetermined intervals so that their tips 3a are located on the same plane, and are opposed to the uneven surface of the DUT 10 so as to be relatively movable in a direction orthogonal to the arrangement direction. It is provided. Rod-shaped core 3
Are provided with detecting means 5 for detecting a change in magnetic flux generated due to the uneven shape of the device under test 10, and the output of the detecting means 5 is A / A at a predetermined timing.
D-converted and stored in the memory 25 (FIG. 2).
The uneven shape of the device under test 10 is detected from the data stored in 5.

Now, as shown in FIG. 4, if the relative movement direction of the DUT 10 is the direction of the arrow in the figure, the width w of the tip 3a of each rod-shaped core 3 in the movement direction, ie, the width of the rod-shaped core 3, The length w of the two sides along the relative movement direction among the four sides of the tip surface is set to be smaller than the width of the uneven shape of the DUT 10 to be detected. Tip 3 of rod-shaped core 3
Since “a” is smaller, the resolution is improved. Therefore, it is preferable that “a” is formed smaller and has a pointed shape. The rod-shaped core 3 may be formed in a prismatic shape as shown in the figure, or may be formed into a tapered shape (not shown), for example, so as to have both a narrow tip 3a and strength.

The detection means 5 is, for example, a detection coil wound around the rod-shaped core 3. In addition, FIG.
As shown in the figure, on both sides of the rod-shaped core 3 in the relative movement direction, auxiliary cores 7 for forming a magnetic flux passage having the same width as the rod-shaped core 3 are integrated with the same number of rod-shaped cores 3 arranged in a large number. Is formed. When the auxiliary core 7 is integrally formed as described above, a path for the magnetic flux generated from the distal end 3a of the rod-shaped core 3 is secured, so that the sensitivity as the surface shape detecting sensor 1 can be improved. However, the core is not particularly limited to such a shape. For example, the auxiliary core 7 may be formed only on one of the rod-shaped coils 3 or the formation of the auxiliary cores 7 on both sides may be omitted. It is possible.

Exciting coils 6 are wound around the auxiliary cores 7 on both sides, respectively. A rectangular high-frequency signal 14 as shown in FIG. 5 is applied to each excitation coil 6 as an excitation signal, and a magnetic field is generated in a space in which the device under test 10 relatively moves. In this magnetic field, the DUT 10
Passes, the magnetic flux changes due to the uneven shape, and the output of the detection coil 5 changes accordingly. The output of each detection coil 5 is the amplifier circuit 1 of the detection signal circuit 27 shown in FIG.
After being amplified by 1, half-wave rectification is performed by the detection circuit 12 and the peak hold circuit 13 and the envelope detection is performed.
The analog signal has a waveform proportional to the uneven shape of the device under test 10. Then, as shown in FIG.
Is supplied to an analog multiplexer 26. The analog multiplexer 26 is provided for each detection coil 5.
Are sequentially supplied to the A / D converter 29 at a predetermined timing based on a pulse from the synchronous clock 28. The signals digitally converted by the A / D converter 29 are sequentially stored in the memory 25. The DUT 1
When 0 is a metal or the like, for example, the eddy current generated in the DUT 10 acts to reduce the magnetic flux generated from the rod-shaped core 3, so that the output signal of the detection coil 5 changes. When the device under test 10 is a magnetic material, for example, the output signal of the detection coil 5 changes because the leakage of magnetic flux from the device under test 10 decreases. Therefore, the surface shape detecting sensor 1 of the present invention can detect the uneven shape of the surface not only when the measured object 10 is a metal or the like, but also when it is a magnetic material or the like.

In the surface shape detecting sensor 1, as shown in FIG. 1, the cores 3, 7 and the coils 5, 6 are arranged in a line in a direction perpendicular to the direction of relative movement. A line sensor is configured. The line sensor is arranged such that the DUT 10 relatively moves in a magnetic field generated by each excitation coil 6. In this case, a separation groove 18a having the same width is formed between the rod-shaped core 3 and the auxiliary core 7, and the cores 3 and 7 are separated by the separation groove 18a so as to have a constant shape. Also, on both sides of the relative movement direction of the auxiliary core 7,
Step 1 for mounting the exciting coil 6 to which a high-frequency signal is applied
8b are formed. In this case, the separation groove 18a and the stepped portion 18b may be formed so that the heights of the bottom surfaces thereof are equal to each other. However, in the present embodiment, the detection coil is formed in a stepped shape as shown in FIG. 5 and the exciting coil 6 are made different in height. This allows
The sensitivity when detecting a change in magnetic flux can be improved,
The change in the pattern of the uneven shape can be represented in a graph in more detail. Further, a separation groove 1 is provided between the rod-shaped cores 3.
A separating groove 18c having a groove depth is formed from the step 8a and the step 18b for attaching the exciting coil, and separates the rod-shaped core 3 and the auxiliary core 7 from each other. In addition, many rod-shaped cores 3
It is needless to say that the width w of the tip 3a in the relative movement direction is formed to be the same width smaller than the width of the uneven shape to be detected. In this case, each of the separating grooves 18c can be accurately formed into the same shape and the same size as the bar-shaped core 3 by machining, for example.
A highly accurate line sensor having no deviation in the relative movement direction can be formed.

Hereinafter, the surface shape detecting sensor 1 of the present invention will be described.
In one embodiment, assuming that the surface unevenness of a one-yen coin shown in FIG. 12A is detected as the object to be measured 10, the detection provided on the rod-shaped core 3 located at the center in the longitudinal direction of the line sensor. The coil 5, that is, the detection coil 5 provided on the rod-shaped core 3 opposed to the center position when the coin 10 relatively moves will be examined. Since the smallest width of the surface of the one-yen coin is the edge portion, if the width w of the tip 3a of the rod-shaped core 3 is smaller than the width of the edge portion, all surface irregularities of the coin are detected. Will be able to However, when it is sufficient to detect the uneven shape of the pattern portion without performing the shape detection of the edge portion, the size of the width w is set to be smaller than the smallest width among the widths of the uneven shape of the pattern portion to be detected. Should also be reduced. For example, FIG.
In the case of (B), the width w may be determined in a certain range of the uneven shape to be detected, such as by setting the width of the uneven shape to be detected, for example, the width w smaller than W1 and W2. Alternatively, it is only necessary to determine to what size the width of the uneven shape to be detected is to be detected, and make the width smaller than the width. In this case, it is possible to clearly detect irregularities having a width of a size desired to be detected, but it is also possible to roughly understand shapes of irregularities having a small width which need not be detected. By determining the size of the width w based on the minimum width in this manner, even if the relative movement locus of the rod-shaped core 3 is, for example, the P-line or the Q-line shown in FIG. Can be performed favorably.

The detection signal circuit 27 corresponding to the detection coil 5 outputs, for example, the signals shown in FIG.
An output signal as shown in FIG. In the table showing such a waveform diagram, the vertical axis represents the output signal, and the horizontal axis represents the relative position of the DUT 10 with respect to the surface shape detecting sensor 1. The output signal in this case is displayed so as to be lower corresponding to the convex portion of the coin 10 and to be higher corresponding to the concave portion. Until the coin 10 faces the rod-shaped core 3, the output is higher than in the case where the coin corresponds to the concave portion, and the same output is obtained if there is a hole in the middle. That is, the waveform of the output signal corresponds to the uneven shape of the surface of the coin 10, but at the same time, information 21 relating to the difference in height between the edge and the center of the coin 10, information 22 relating to the width of the edge, Information 23 about a diameter, information 24 about a material and thickness, etc. can be obtained. Therefore,
When used as a coin identification sensor, these information 21 to 24 are added to the information on the surface irregularities.
Can be detected simultaneously.

The width w of the tip 3a of the rod-shaped core 3 in detecting the surface unevenness of the coin 10 in this manner is:
The value is set to a value smaller than the width of the uneven shape of the surface of the coin 10, for example, a value of 2 mm or less. When the width w is larger than 2 mm, the resolution of the detection of the unevenness on the surface of the coin 10 becomes coarse, and it becomes difficult to detect the fine unevenness. This is because it becomes inferior. However, it is not always necessary to set the width w to 2 mm or less, and the width w may be set to an appropriate value according to the width of the uneven shape. In addition, when it is sufficient to roughly detect the uneven shape, it is not always necessary to set the width w to be smaller than the width of the uneven shape. The width w may be set to the calculated value.

Each of the detection signal circuits 27 connected to each of the detection coils 5 outputs an analog signal having a waveform proportional to the uneven shape of the surface of the coin 10.
That is, as shown by a circle in FIG. 7, if the coin 10 and the line sensor are relatively moved only once, data on the uneven shape of the surface of the coin 10 is detected in a mesh form, so that the relative movement of the line sensor The entire surface of the coin 10 can be detected within the range. Such a line sensor is
For example, it can be used as a coin identification sensor incorporated in a coin identification device or the like of a vending machine. However, this is merely an example, and it is a matter of course that the present invention is not limited to coin identification.

Next, a method for manufacturing the surface shape detecting sensor 1 of the present invention will be described. In the present invention, the surface shape detecting sensor 1 is formed such that the tips 3a of a large number of rod-shaped cores 3 arranged in a row at predetermined intervals are arranged on the same plane. . In order to form the ferrite block 18 in this manner, first, a groove having a predetermined width in the arrangement direction, that is, the separation groove 18a referred to here is processed in the longitudinal direction on the ferrite block 18 having a prism shape as shown in FIG. (FIG. 8B). In this embodiment, as shown in the figure, two separation grooves 18a are machined, and the rod-shaped core 3 is interposed therebetween.
Is formed, and a stepped portion 18b parallel to this is further processed outside to form the auxiliary core 7. Then, a large number of rod-shaped cores 3
By forming the separating grooves 18c for separating the cores, the same number of auxiliary cores 7 for forming the magnetic flux paths as the rod cores 3 are integrally formed on both sides of the many rod cores 3. In this case, the separation grooves 18c formed between the rod-shaped cores 3 are formed so as to have a groove width that allows the respective coils 5 and 6 of the rod-shaped core 3 to be arranged. The coils 5 and 6 can be installed on the core 3 or the auxiliary core 7. Then, the surface shape detection sensor 1 is formed by attaching at least one of the detection coil 5 or the exciting coil 6 to the rod-shaped core 3 in a state in which many rod-shaped cores 3 are formed in one block. The manufacturing method of the surface shape detecting sensor 1 is not particularly limited to the above-described one, and for example, the order of forming the separation groove 18a, the step portion 18b, and the separation groove 18c can be appropriately changed. .

According to the surface shape detecting sensor 1 configured as described above, it is possible to detect the magnetic flux that changes due to the uneven shape of the surface of the device under test 10. Moreover, since the width w of the rod-shaped core 3 is formed to be smaller than the width of the concavo-convex shape, for example, the tip 3a of the rod-shaped core 3 has a pointed shape. A feature proportional to the surface shape of the object 10 is shown as a pattern graphic. Therefore, the surface irregularities of the DUT 10 can be detected from the pattern figure. In addition, the uneven shape can be detected in a non-contact state without touching the core or the like. Furthermore, since a number of rod-shaped cores 3 are arranged in a line to form a line sensor, the DUT 10 is set to be orthogonal to this arrangement direction.
Is relatively moved, the entire surface shape of the DUT 10 can be detected by a one-time operation.

According to the method of manufacturing the surface shape detecting sensor 1 of the present invention described above, the distance between the sensor chips such as the rod-shaped core 3 is machined to form an integrated structure, so that the distance between the sensor chips can be accurately determined. Can be specified. Therefore, a high-precision line sensor that does not shift in the moving direction of the device under test 10 can be supplied by converting it into a sensor in an integrated bar state. Moreover, according to the present invention, the operation is much simpler than the operation of accurately mounting each sensor chip one by one.

The above embodiments are examples of preferred embodiments of the present invention, but are not limited thereto, and various modifications can be made without departing from the gist of the present invention. For example, in the above description, the line sensors are configured by arranging the rod-shaped cores 3 and the like in a line, but the line sensors may be configured by arranging the rod-shaped cores 3 in a plurality of lines. That is, a plurality of sets of rod-shaped cores 3 arranged in a row and separated from one another
0 may be arranged so that the rod-shaped cores 3 in the rear row are located between the rod-shaped cores 3 in the front row with respect to the relative movement direction. In FIG. 9, for example, two rod-shaped cores 3 arranged in a row are arranged in the relative movement direction of the DUT 10, for example, in two sets. FIG. In this case, since the rod-shaped cores 3 in the first row and the rod-shaped cores 3 in the second row are alternately arranged, the relative movement trajectories of the rod-shaped cores 3 in each row do not overlap, and the number of the rod-shaped cores 3 is increased. The surface shape of the DUT 10 can be detected in a dense state. For example, when the interval between the rod-shaped cores 3 in a row cannot be reduced too much due to structural or processing restrictions, or when the adjacent detection coils 5
Even if it is necessary to widen the interval between the rod-shaped cores 3 in order to prevent magnetic interference, the number of rows of the rod-shaped cores 3 can be increased so that the relative movement locus of the rod-shaped cores 3 can be made denser and the rod-shaped core 3 can be covered. The measurement object 10 can be detected.

In the above description, the detection means is the detection coil 5 wound around the rod-shaped core 3, but a magneto-resistance effect element (MR element) attached to the rod-shaped core 3 instead of the detection coil 5 May be used. In this case, for example, the tip 3a of the rod-shaped core 3 may be divided into two parts, and the magnetoresistive element may be embedded and used between the two parts. Since the internal resistance of the magnetoresistive element changes due to the magnetic flux that changes due to the uneven shape of the surface of the device under test 10, a change in the magnetic flux can be detected by detecting this.

In the above description, the surface shape detecting sensor 1 has two coils, that is, the detecting coil 5 and the exciting coil 6.
Need not be provided, and these may be formed into one coil. In this case, excitation may be performed by one coil and a change in magnetic flux may be detected based on a change in inductance in the coil.

Further, the signal applied to the exciting coil 6 is not necessarily limited to a high-frequency signal, but may be a signal corresponding to the DUT 10 or its detection resolution.

[0032]

EXAMPLE In order to investigate the relationship between the width w of the tip 3a of the rod-shaped core 3 and the resolution for detecting unevenness, the value of the width w was changed to 5
An experiment was performed to detect the surface shape of a 00 yen coin. FIG.
11 shows a waveform of an output signal of the detection coil 5 when the width w is 0.5 mm, and FIG. 11 shows a waveform of an output signal of the detection coil 5 when the width w is 3 mm. If the width w is 3 mm (FIG. 11), the waveform of the output signal becomes flat as a whole, and information 21 relating to the height difference between the edge and the center of the 500 yen coin, and information relating to the diameter Although the information 23 and the information 24 relating to the thickness of the material can be confirmed, it is difficult to detect the uneven shape of the surface. On the other hand, if the width w is 0.
When the distance is 5 mm (FIG. 10), the change in the shape of the output signal favorably follows the change in the surface shape of the 500-yen coin. Thus, it was confirmed that by reducing the width w, it was possible to detect fine features of fine irregularities better. In addition, it was found that by setting the width w to 0.5 mm, it was possible to obtain a resolution sufficient for use as a sensor for discriminating the type and authenticity of coins.

[0033]

As is apparent from the above description, in the surface shape detecting sensor according to the first aspect of the present invention, the tips of a large number of rod-shaped cores are arranged on the surface of a metal object having irregularities in a magnetic field. Since each of the rod-shaped cores is provided with a detecting means for detecting a magnetic flux that changes due to the uneven shape of the measured object, the rod-shaped core is provided so as to be relatively movable in a direction orthogonal to the direction. The uneven shape can be detected. Moreover, since the tips of a large number of rod-shaped cores arranged at predetermined intervals on a single common base are arranged on the same plane, the uneven shape of the object to be measured is Non-contact detection is possible.

In the surface shape detecting sensor according to the second aspect of the present invention, the width of the tip in the relative movement direction of the plurality of rod-shaped cores is set to be the same width smaller than the width of the concavo-convex shape to be detected. It is possible to detect in detail, thereby detecting the uneven shape of the surface of the object to be measured. Further, since the detecting means is a detection coil wound on a rod-shaped core or a magnetoresistive effect element attached to the rod-shaped core, a change in magnetic flux is caused by changing a current of the detection coil or an internal resistance of the magnetoresistive element. Can be electrically detected by changing

In the surface shape detecting sensor according to the third aspect of the present invention, an auxiliary core for forming a magnetic flux path having the same width as the rod-shaped core in the relative movement direction is provided on both sides of the rod-shaped core in the relative movement direction. The same number of rod-shaped cores are formed in one piece, and the same width of the separation groove is formed between the rod-shaped core and the auxiliary core. Sensitivity can be improved.

In the surface shape detecting sensor according to the present invention, the auxiliary core may be provided on both sides in the relative movement direction.
Since a step for mounting the exciting coil to which a high-frequency signal is applied is formed, a separating groove having a depth greater than that of the step for mounting the exciting coil is formed between the rod-shaped cores. The sensitivity can be improved by separating the detection coil and the exciting coil from each other. Moreover, if the distance between the bottom of the separation groove and the step is different from the tip of the rod-shaped core, the detection coil and the exciting coil can be installed in a step-like manner, further improving the sensitivity of the sensor. be able to.

According to a fifth aspect of the present invention, in the method of manufacturing a surface shape detecting sensor, the tips of a large number of rod-shaped cores arranged in a row at a predetermined interval are arranged on the same plane. A groove having a predetermined width is formed in the arrangement direction, and a separation groove for separating a large number of rod-shaped cores is formed in a direction orthogonal to the groove processing, and a separation groove formed between the rod-shaped cores. Is formed so as to have a groove width that allows a coil to be arranged in each of the rod-shaped cores, and at least one of the detection coil or the excitation coil is formed on the rod-shaped core in a state where a large number of rod-shaped cores are formed in one block. Since one of them is attached, a highly accurate surface shape detecting sensor can be simply and integrally formed.

In the method of manufacturing a surface shape detecting sensor according to the present invention, the same number of auxiliary cores for forming magnetic flux paths as the number of rod-shaped cores are integrally formed on both sides of the plurality of rod-shaped cores.
Since the separation groove formed between the rod-shaped cores is formed to have a width that allows the detection coil and the excitation coil to be arranged, a line sensor type high-precision surface shape detection sensor is formed. be able to.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a surface shape detection sensor according to the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a surface shape detection sensor and a detection signal circuit.

FIG. 3 is a plan view of the surface shape detection sensor of FIG. 1;

FIG. 4 is a perspective view showing a part of a surface shape detecting sensor for explaining a width w of a tip end of a rod-shaped core.

FIG. 5 is a circuit diagram showing a detection signal circuit of FIG. 2;

6 is a diagram illustrating an example of an output signal of the detection signal circuit of FIG.

FIG. 7 is a conceptual diagram showing a state of detection by the surface shape detection sensor of FIG. 1;

8A and 8B schematically show a manufacturing process of a core of the sensor for detecting a surface shape in FIG. 1; FIG. 8A is a perspective view of a ferrite block;
(B) is a perspective view of a ferrite block in which a separation groove and a step are processed, and (c) is a perspective view of a ferrite block in which a rod-shaped core and an auxiliary core are processed.

FIG. 9 is a plan view showing a state in which two sets of rod-shaped cores of the surface shape detection sensor are arranged.

FIG. 10 shows a case where the width w of the tip of the rod-shaped core is 0.5 mm;
It is a figure which shows the sensor output at the time of measuring the uneven | corrugated shape of a 00 yen coin.

FIG. 11: 500 when the width w of the tip of the rod-shaped core is 3 mm
It is a figure which shows the sensor output at the time of measuring the uneven | corrugated shape of a yen coin.

FIG. 12 is a diagram for explaining the relationship between the width w of the tip end surface of the rod-shaped core and the width of the uneven shape of the measured object;
FIG. 2A is a plan view of a one-yen coin (object to be measured), and FIG.

[Explanation of symbols]

 Reference Signs List 1 line sensor 2 base 3 rod-shaped core 3a tip 5 detection coil (detection means) 6 excitation coil 7 auxiliary core 10 DUT 14 high-frequency signal w

Claims (6)

[Claims] 1. A plurality of rod-shaped cores arranged at a predetermined interval on a common base such that tips of the rod-shaped cores are on the same plane, and the tips of the rod-shaped cores are placed in a magnetic field. In the uneven surface of the metal object to be measured in the direction perpendicular to the arrangement direction and relatively movably opposed to each other, the magnetic flux that changes due to the uneven shape of the object to be measured in each of the rod-shaped cores. A surface shape detection sensor comprising a detection unit for detecting the surface shape. 2. The detection coil wound around the rod-shaped core, wherein the width of the tip of each of the rod-shaped cores in the direction of relative movement is smaller than the width of the concavo-convex shape to be detected. The surface shape detecting sensor according to claim 1, wherein the sensor is a magnetoresistive element attached to the rod-shaped core. 3. An auxiliary core for forming a magnetic flux path having the same width as the rod-shaped core in the relative movement direction is integrally provided on both sides of the rod-shaped core with respect to the relative movement direction. The surface shape detecting sensor according to claim 1, wherein a separation groove having the same width is formed between the rod-shaped core and the auxiliary core. 4. A step for mounting an exciting coil to which a high-frequency signal is applied is formed on both sides of the auxiliary core in the relative movement direction, while the separating groove and the exciting coil are provided between the rod-shaped cores. 4. The surface shape detecting sensor according to claim 3, wherein a separating groove having a groove depth greater than that of the mounting step is formed. 5. A block having a predetermined width in the arrangement direction is formed on one block so that tips of a large number of rod-shaped cores arranged in a row at predetermined intervals are arranged on the same plane. Separation grooves for separating the plurality of rod-shaped cores are formed in a direction orthogonal to processing, and a separation groove formed between the rod-shaped cores is provided with a coil in each of the rod-shaped cores. A surface having a groove width that allows the above, and attaching at least one of a detection coil or an excitation coil to the rod-shaped core in a state where a plurality of rod-shaped cores are formed in the one block. Manufacturing method of shape detection sensor. 6. An auxiliary core for forming a magnetic flux path is integrally formed on both sides of the plurality of rod-shaped cores in the same number as the rod-shaped cores.
6. The surface shape detecting sensor according to claim 5, wherein the separating groove formed between the rod-shaped cores is formed to have a width that allows a detection coil and an excitation coil to be arranged. Production method.