JP2007271489A - Method and device for measuring processing residual thickness - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for measuring processing residual thickness of a resin member with reduced work hours by enabling measurement of the processing residual thickness on a real time basis. <P>SOLUTION: This method for forming a tear line 11 on the resin member 10 by a groove forming member 21 and measuring the processing residual thickness of the resin member 10 left after forming of the tear line, includes a detection process of arranging an eddy current sensor 33 on backside of a tear line forming side 10a of the resin member 10, inducing eddy current on the groove forming member 21 being inserted into the resin member 10 by the eddy current sensor 33, and detecting an output voltage based on the induced eddy current, and a measurement process of operating a distance D between the eddy current sensor 33 and the groove forming member 21 from the output voltage detected in the detection process, and determining a thickness of a groove processing part 12 of the resin member 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a measurement method and a measurement apparatus for a remaining machining thickness, and more particularly to a measurement method and a measurement apparatus for a remaining machining thickness for measuring a remaining machining thickness of a resin member left by forming a tear line.

  For example, a resin member such as an instrument panel is provided at a predetermined location in a driver's cab of an automobile or the like, and among them, the resin member provided so as to cover the airbag device has a A groove-shaped cleavage line called a tear line is formed on the back surface so as to be easily broken. Usually, this tear line is formed by, for example, a groove forming member such as a heated processing blade being inserted into the inside from the resin member surface, and then the groove forming member is pulled out in the vertical direction or the horizontal direction.

  By the way, in the tear line formation process, in order to improve the deployment performance of the airbag device and the appearance quality of the resin member, the remaining thickness of the resin member (processing remaining thickness) left by the tear line formation, that is, the thickness of the groove processing portion It is important to control so that is constant within the set value range. From this point of view, many measurement methods for measuring the remaining processing thickness of a resin member on which a tear line is formed have been proposed.

As shown in FIG. 9, for example, a laser sensor 133 is used to measure the remaining thickness by irradiating the back of the groove processing portion 112 of the resin member 110 with a laser after forming the tear line (FIG. 9A In addition, the resin member 110 is pushed up by the push-up pin 113 from the back side of the tear line forming surface 110a to temporarily widen the groove processing portion 112 of the tear line 111, and the back portion of the groove processing portion 112 A measurement method (see FIG. 9B) for measuring the remaining thickness by irradiating a laser on the surface has been proposed.
Further, Patent Document 1 discloses a measurement in which a processing remaining thickness of a resin member having a tear line in which side surfaces are in close contact with each other and side surfaces are not in contact is measured using an ultrasonic sensor. A method is disclosed (see Patent Document 1).
JP 2005-17130 A

However, in the conventional measurement method described above, the laser irradiation position from the laser sensor 133 is shifted from the depth of the groove processing portion 112 and an error is likely to occur in the measurement value. The groove processing portion 112 is deformed by temporarily expanding the processing portion, and the appearance quality of the tear line 111 may be inferior.
Above all, with the conventional measurement method, the remaining processing thickness of the resin member can be measured only after the tear line forming process, and the remaining processing thickness of the resin member is measured in real time during the tear line forming process. Since measurement could not be performed, it was difficult to shorten the work time. In this respect, the measuring method described in Patent Document 1 also has a similar problem because the processing remaining thickness cannot be measured in real time.

  Therefore, the present invention relates to a method and apparatus for measuring a remaining working thickness, which solves the above-described conventional problem, and measures the remaining working thickness by reducing the working time by measuring the remaining working thickness of a resin member in real time. It is an object to provide a method and a measuring device.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, there is provided a method for measuring a processing remaining thickness by forming a tear line on a resin member by a molded member and measuring a processing remaining thickness of the resin member remaining by the formation of the tear line, Detection that detects an output voltage based on the induced eddy current by arranging an eddy current sensor behind the tear line forming surface and inducing an eddy current in the groove forming member inserted into the resin member by the eddy current sensor. And a measuring step of calculating a distance between the eddy current sensor and the groove forming member from the output voltage detected by the detecting step to obtain a processing remaining thickness of the resin member.

  In the present invention, the measuring step measures a distance between the eddy current sensor and a cutting edge portion for forming a tear line formed on the groove forming member.

  According to a third aspect of the present invention, in the measuring step, the eddy current sensor is disposed immediately below the groove forming member, and the eddy current sensor is moved in conjunction with the movement of the groove forming member that is linearly moved in the horizontal direction. is there.

  According to a fourth aspect of the present invention, there is provided a processing remaining thickness measuring device that forms a tear line on a resin member by a groove forming member and measures a remaining processing thickness of the resin member left by the formation of the tear line. An eddy current sensor is provided on the back side of the line forming surface, and an eddy current is induced in the groove forming member inserted into the resin member by the eddy current sensor, and an output voltage based on the induced eddy current is detected. It has a detection part and a measurement part which calculates the distance between the eddy current sensor and the groove forming member from the output voltage detected by the detection part and obtains the processing remaining thickness of the resin member.

  As effects of the present invention, the following effects can be obtained.

  Since the method according to claim 1 is used, the tiered line is formed by measuring the distance between the eddy current sensor and the groove forming member by inducing an eddy current with the eddy current sensor to the groove forming member in the middle of forming the tear line. The remaining machining thickness can be measured in real time, and the working time can be effectively shortened.

  Since it was set as the method shown in Claim 2, the measurement precision of process remaining thickness can be improved on the basis of the blade edge | tip part which reaches | attains even the innermost part of a resin member.

  Since it is set as the method shown in Claim 3, the processing remaining thickness of a resin member can be measured in real time over the full length of a tear line, and the product precision of a tear line can be improved.

  Since the structure shown in claim 4 is used, the tiered line is formed by measuring the distance between the eddy current sensor and the groove forming member by inducing an eddy current with the eddy current sensor with respect to the groove forming member in the middle of forming the tear line. The remaining machining thickness can be measured in real time, and the working time can be effectively shortened.

Next, the best mode for carrying out the invention will be described.
FIG. 1 is a side view showing an overall configuration of a tear line forming apparatus according to an embodiment of the present invention. 2 is a plan view of a resin member on which a tear line is formed, FIG. 3 is a cross-sectional view showing a state in which the thickness of the groove processing portion is measured by the detection portion, and FIG. 4 is a block diagram of the remaining thickness measurement portion. 5 is a flowchart showing a procedure for calculating the distance between the eddy current sensor and the groove forming member in the measurement unit, FIG. 6 is a diagram showing an output voltage waveform detected by the detection unit, FIG. 7 is a diagram showing a calculation table, 8 is a side view showing a state of measuring the thickness of the grooved portion in another embodiment, and FIG. 9 is a cross-sectional view showing a state of measuring the remaining processing thickness of the conventional resin member.

First, the overall configuration of the tear line forming apparatus 1 of this embodiment will be outlined below.
As shown in FIG. 1, the tear line forming device 1 is provided with a tear line forming portion 2 and a remaining thickness measuring portion 3 as a processing remaining thickness measuring device, and the tear line forming portion 2 is formed on the surface of the resin member 10. The remaining thickness (working remaining thickness) of the remaining resin member 10 can be measured in real time by the remaining thickness measuring unit 3 while forming the tear line 11.

  The resin member 10 is formed of a resin material such as polypropylene, and is used as a member constituting an instrument panel skin or a handle panel skin in a driver's cab of an automobile or the like. In the following embodiments, the resin member 10 is mainly used for the skin of an instrument panel that is attached so as to cover the air bag device on the passenger side of the automobile. The resin member 10 has a tear line 11 formed of a plurality of groove-shaped cleavage lines on a surface (hereinafter referred to as a tear line forming surface 10a) facing the airbag device.

As shown in FIGS. 2 and 3, the tear line 11 is opened on the tear line forming surface 10 a of the resin member 10, and the opposing side walls in the opening are substantially parallel to the back of the paper surface in FIG. 3. It is formed in a substantially U-shaped cross section so as to be formed, is recessed without penetrating the resin member 10 toward the inner direction of the resin member 10, and a groove processing portion 12 is formed in the remaining portion. And the thickness L of this groove process part 12 is corresponded to the process remaining thickness of the resin member 10, and the thickness L of this groove process part 12 is calculated by the remaining thickness measurement part 3 mentioned later in a present Example.
In addition, although the tear line 11 of a present Example is formed in five crack lines, the arrangement | positioning of the tear line 11 is not limited to this, It changes suitably in consideration of the expansion | deployment performance of an airbag apparatus.

Next, the tear line forming part 2 will be described in detail below.
Returning to FIG. 1, the tear line forming unit 2 includes a mounting table 20 on which the resin member 10 is mounted and fixed, a groove forming member 21 that forms a tear line on the tear line forming surface 10 a of the resin member 10, and a groove forming member. The movable arm mechanism 22 and the like are supported by the movable arm mechanism 21 so as to be movable in three axial directions.
The mounting table 20 is placed on the horizontal surface formed on the upper surface of the resin member 10 with the tear line forming surface 10a facing upward. The mounting table 20 of the present embodiment includes a suction mechanism (not shown) that sucks the mounting surface of the resin member 10 in a direction (downward in FIG. 1) that attracts the mounting surface of the resin member 10 to the horizontal plane. Has been. By suctioning the resin member 10 by this suction mechanism, the tear line forming surface 10a can be fixed so as to be substantially horizontal, and workability when forming the tear line 11 and the quality of the tear line 11 can be improved. .

The groove forming member 21 is integrally formed from high-purity blade steel, and a cutting edge portion 21a for forming a tear line is ground on one side. The groove forming member 21 is horizontally moved by the movable arm mechanism 22 in a state where the blade edge portion 21 a is inserted into the resin member 10 from vertically above the tear line forming surface 10 a and the blade edge portion 21 a is inserted into the resin member 10. Is moved in the direction (see FIG. 3).
In this embodiment, the groove forming member 21 is used at room temperature without heating the blade edge portion 21a. Further, the shape and configuration of the groove forming member 21, the blade edge angle of the tear line 11, the blade shape, and the like are not particularly limited, but are formed of at least a magnetic material as described later.

The movable arm mechanism 22 includes a support arm 24 to which the groove forming member 21 is attached, a connection portion 25 that supports the support arm 24 so as to be movable in the horizontal direction (XY direction), and the connection portion 25 that moves up and down. It is comprised with the machine stand 26 etc. which are supported and fixed freely.
The groove forming member 21 described above is attached to the support arm 24 so that the cutting edge portion 21a faces vertically downward, and the resin member on which the groove forming member 21 is placed on the mounting table 20 by the support arm 24. It is positioned so as to face the ten tear line forming surface 10a.

  The connecting portion 25 includes a connecting shaft portion 25a whose one end is fixed to the machine base 26, a horizontal shaft portion 25b slidably attached to the connecting shaft portion 25a, and the like. The connecting shaft portion 25a and the horizontal shaft portion 25b are composed of rod-shaped members having a substantially rectangular cross section. The horizontal shaft portion 25b is attached in a direction orthogonal to the connecting shaft portion 25a, and one end is provided on the connecting shaft portion 25a. It is attached to a rail (not shown) and is slidable in the axial direction. The above-described support arm 24 is slidably attached to the horizontal shaft portion 25b along the axial direction.

The machine base 26 is provided with an elevating member 26a fixed in a vertically expandable / contractible manner, and one end of a connecting portion 25 (connecting shaft portion 25a) is connected to the elevating member 26a. Then, when the elevating member 26a is moved up and down with respect to the main body 26, the connecting portion 25 and the support arm 24 are moved up and down integrally with the elevating member 26a.
The horizontal shaft portion 25b and the elevating member 26a described above are controlled by a drive mechanism (not shown) so that the tear line 11 is formed at a predetermined location.

With the configuration as described above, in the movable arm mechanism 22, the groove forming member 21 can be freely moved in the triaxial directions (XYZ directions), and the resin placed on the mounting table 20. A predetermined tear line 11 can be formed on the tear line forming surface 10a by moving the groove forming member 21 (blade edge 21a) relative to the member 10.
However, the configuration of the movable arm mechanism 22 is not limited to this, and is configured such that at least the groove forming member 21 can be freely moved with respect to the resin member 10.

  Here, the formation process of the tear line 11 by the tear line forming part 2 will be described in detail. First, the tear line forming part 2 is in a state where the resin member 10 is placed on the placing table 20 and the groove forming member 21 is resin. It is located above the member 10 and stopped. Then, the connecting portion 25 of the movable arm mechanism 22 is operated, the groove forming member 21 is moved in the horizontal direction, and the cutting edge portion 21a is positioned at a predetermined position in the horizontal direction with respect to the tear line forming surface 10a and stopped. The Subsequently, the elevating member 26a of the movable arm mechanism 22 is operated, and the support arm 24 and the connecting portion 25 are integrally moved downward in the vertical direction, that is, the direction in which the blade edge portion 21a is close to the tear line forming surface 10a. Soon, the blade edge portion 21a is inserted into the resin member 10 from vertically above the tear line forming surface 10a, and the elevating member 26a is stopped at a position not penetrating the resin member 10. Then, with the cutting edge portion 21a inserted into the resin member 10, the horizontal shaft portion 25b of the movable arm mechanism 22 is operated, and the groove forming member 21 is linearly moved in the horizontal direction.

  In this way, a predetermined tear line 11 is formed at a predetermined position on the tear line forming surface 10a. Further, in this embodiment, the tear line 11 is formed by cutting the surface of the tear line forming surface 10a of the resin member 10 by the cutting edge portion 21a, so that the side wall facing the tear line 11 at the opening is the back of the page. It can be formed in a substantially U-shaped cross section so as to be formed substantially parallel to the part (see FIG. 3), and the appearance and shape of the tear line 11 are excellent, and the appearance quality can be improved.

Next, the remaining thickness measuring unit 3 will be described in detail below.
As shown in FIGS. 1, 3, and 4, the remaining thickness measuring unit 3 is a processing remaining thickness measuring device that calculates a thickness L of the groove processing unit 12 that is a processing remaining thickness of the resin member 10, From the output voltage obtained by the detection unit 30 that detects the output voltage based on the eddy current by inducing an eddy current in the groove forming member 21 that has the sensor 33 and is inserted into the resin member 10 In addition, the distance D between the eddy current sensor 33 and the groove forming member 21 (the blade edge portion 21a) is calculated, and the measurement unit 31 is configured to calculate the thickness L of the groove processed portion 12 formed in the resin member 10. Yes.

  The detection unit 30 is provided with an eddy current sensor 33 as a means for detecting an output voltage based on an eddy current. In addition, an oscillation circuit (not shown) that supplies a predetermined value of current to an excitation coil provided in the eddy current sensor 33, A detection circuit (not shown) or the like that receives a signal from a detection coil provided in the eddy current sensor 33 is provided. In the detection unit 30, when an electric current (alternating current) is supplied to the exciting coil of the eddy current sensor 33, an applied magnetic field (magnetic flux) is generated. In this state, when an object enters the magnetic field of the detection unit 30, an eddy current is induced in the direction to cancel the magnetic field in the object, and a voltage (output voltage) based on the eddy current is provided in the eddy current sensor 33. It is detected by the detection coil. In the present embodiment, this object corresponds to the groove forming member 21 (blade edge portion 21a) described above.

  A plurality of detection units 30 are arranged on the surface portion of the mounting table 20 provided in the tear line forming unit 2 and are in contact with the back surface of the resin member 10 on the side opposite to the tear line forming surface 10a. 33 and the resin member 10 are arranged so as not to be spaced apart. Specifically, the detection unit 30 is on the back side of the tear line forming surface 10a of the resin member 10 and is vertically below a portion where the tear line 11 is to be formed in the resin member 10 (five locations in FIG. 2). It is arranged at each position.

  In addition, the “location where the tear line 11 is to be formed on the resin member 10” means, in other words, a location that coincides with the movement path of the groove forming member 21 in a plan view, and the detection unit 30 has a vertical position. The groove forming member 21 is disposed at a location where the groove forming member 21 moves linearly across the upper space. The distance D between the eddy current sensor 33 and the groove forming member 21 refers to the shortest distance from the eddy current sensor 33 to the cutting edge portion 21 a located at the innermost portion of the resin member 10.

  When the detection unit 30 is arranged in this way, the groove forming member 21 inserted into the resin member 10 is moved and passes through the upper part of the detection unit 30 in the vertical direction. Is induced, and the output voltage based on this eddy current can be detected by the detector 30. In the remaining thickness measurement unit 3, the distance D between the eddy current sensor 33 and the groove forming member 21 is calculated from the output voltage detected in this way by the detection unit 30 in the measurement unit 31 described later. The thickness L of the groove processing portion 12 is calculated (see FIG. 3).

  As shown in FIG. 4, the measurement unit 31 is connected to the detection unit 30 via a wiring 32 and is configured to receive a signal from a detection coil provided in the eddy current sensor 33. Specifically, the measurement unit 31 includes a CPU 41 that performs various processes, a memory 42 that stores various processing programs, an input unit 43 as an operation input unit for the UPU 41, a CRT, a liquid crystal display, and the like. The display unit 44 includes an output unit 45 serving as an output interface with an external device.

  The CPU 41 is configured such that a signal from a detection coil provided in the eddy current sensor 33 is digitized and inputted by an A / D conversion circuit (not shown) and various processes are executed. Specifically, the CPU 41 calculates the distance D between the eddy current sensor 33 and the groove forming member 21 from the input output voltage based on the calculation table T stored in the memory 42 as will be described later. From D, the thickness L of the groove machining portion 12 is calculated.

  As the memory 42, a nonvolatile memory such as an EEPROM is used. In addition to a program and various setting data necessary for the processing of the CPU 41, a calculation table T (see FIG. 5) showing the relationship between the peak amplitude value P of the output voltage and the distance D. 7) is stored. In this embodiment, the calculation table T is configured so that it can be rewritten by overwriting the corrected deviation from the actual measurement value, and is not limited to one type. A plurality of them may be provided depending on the situation.

The input unit 43 is configured by a member having a plurality of operation keys such as a keyboard, and performs an operation for designating the start of the calculation table T creation process described above, an end operation for the measurement process, and the like.
The display unit 44 can display values such as the calculation table T, the peak amplitude value P, the distance D, and the thickness L of the groove processing unit 12 in addition to the output voltage waveform input to the CPU 41 described above.
Further, in the output unit 45, values such as the calculation table T are output from the output unit 45 to an external device (not shown). The output unit 45 includes an amplifier circuit for amplifying the detection distance after analog conversion, an interface circuit for external output, and the like.

Next, the measuring method of the processing remaining thickness of the resin member 10 in a present Example is explained in full detail.
As shown in FIGS. 5 to 7, the present embodiment is a method of measuring the processing remaining thickness of the resin member 10 using the remaining thickness measuring unit 3 configured as described above. By disposing the detection unit 30 including the eddy current sensor 33 on the back side of the line forming surface 10a, an eddy current is induced in the groove forming member 21 in a state where the blade edge 21a is inserted into the resin member 10, and the eddy current is generated. A detection step for detecting an output voltage based on the output voltage, and a measurement step for calculating a processing thickness of the resin member 10 by calculating a distance D between the eddy current sensor 33 and the groove forming member 21 from the output voltage detected by the detection step. Each method is proposed.

  As shown in FIG. 5, in the detection process, when the cutting edge 21a of the groove forming member 21 is inserted into the resin member 10 and the forming process of the tear line 11 is started (S100), the movement of the groove forming member 21 is controlled. Thus, the tear line 11 is formed in the resin member 10, and the groove forming member 21 inserted into the resin member 10 is eventually disposed below the position where the tear line 11 is to be formed. 30 (vortex sensor 33) passes vertically above (S101). At that time, an eddy current is induced in the groove forming member 21 by the eddy current sensor 33, and an output voltage based on the eddy current is detected by the detection unit 30 (S102).

  Here, as shown in FIG. 6, the output voltage detected by the detection unit 30 (eddy current sensor 33) increases as the distance D between the eddy current sensor 33 and the groove forming member 21 approaches and the oscillation of the output voltage increases. On the other hand, the amplitude decreases, and the amplitude increases as the distance D between the eddy current sensor 33 and the groove forming member 21 increases. That is, in FIG. 6, the distance D between the eddy current sensor 33 and the groove forming member 21 is long in the ranges S1 and S3, and the distance D between the vortex sensor 33 and the groove forming member 21 is short in the range S2. For the groove forming member 21 that is moved while being inserted into the resin member 10, the amplitude value becomes maximum when the groove forming member 21 is closest to the eddy current sensor 33 (see FIG. 3). Hereinafter, the amplitude value in such a case is referred to as a peak amplitude value P).

  Therefore, in this embodiment, as shown in FIG. 7, the eddy current sensor 33 and the blade edge portion 21a are previously separated at a predetermined interval (distance D), and the peak amplitude value P of the output voltage in each separated state is obtained. By measuring each, the attenuation characteristic of the output voltage with respect to the distance D between the eddy current sensor 33 and the blade edge portion 21a is measured. That is, due to the attenuation characteristic of the output voltage, the peak amplitude value P decreases as the distance D between the eddy current sensor 33 and the groove forming member 21 increases, and the measurement result is stored in the memory 42 as the calculation table T. ing.

  In the calculation table T, the peak amplitude value P varies depending on the shape of the coil used as the eddy current sensor 33, the frequency of the applied voltage, the distance to the object, the electrical conductivity of the groove forming member 21, the dielectric constant, and the like. Depending on the installation environment of the eddy current sensor 33 and the purpose of measurement, the eddy current sensor 33 is appropriately re-created and overwritten in the memory 42 and stored.

  In the measurement process, as shown in FIG. 5, the peak amplitude value P is detected from the output voltage waveform input to the measurement unit 31 (S103), and the detected peak amplitude value P is compared with the calculation table T ( S104), the distance D between the eddy current sensor 33 and the groove forming member 21 is calculated (S105). Specifically, referring to FIG. 7, for example, when the peak amplitude value P is P1, the distance D between the eddy current sensor 33 and the groove forming member 21 is calculated as 0.2 mm.

  As described above, since the eddy current sensor 33 is disposed so as to be in contact with the back surface opposite to the tear line forming surface 10a of the resin member 10, the eddy current sensor 33 calculated as described above and the groove formation are arranged. The distance D with respect to the member 21 corresponds to the thickness L of the groove machining portion 12. That is, in the present embodiment, when the distance D is calculated, the thickness L of the groove machining portion 12 is automatically calculated. Then, the calculated thickness L of the groove machining portion 12 is stored in the memory 42. Further, the thickness L of each of the plurality of groove processing portions 12, 12... Is calculated and stored in the memory 42 for each groove processing portion 12.

In the measurement process, the measurement unit 31 determines whether or not the calculated thickness L of the groove processing unit 12 is within a set value range (for example, the thickness L is 0.35 mm to 0.6 mm). Information regarding the determination result is also stored in the memory 42, displayed on the display unit 44, and sent to an external connector or the like via the output unit 45.
When the measurement unit 31 determines that the calculated thickness L of the groove processing unit 12 is outside the set value range, the driving mechanism of the tear line forming unit 2 described above is stopped at the same time, The groove forming member 21 may be controlled to stop moving, or each drive mechanism of the tear line forming unit 2 may be feedback controlled so as to be within a set value range.

  By measuring the remaining processing thickness of the resin member 10 as described above, the processing remaining thickness of the resin member 10 can be measured in real time, and the working time can be shortened. That is, according to the measurement method of the present embodiment, an eddy current is induced by the eddy current sensor 33 of the detection unit 30 with respect to the groove forming member 21 in the middle of forming the tear line 11, and the eddy current sensor 33 and the groove forming member 21. Since the distance D is measured, the remaining machining thickness can be measured in real time during the formation of the tear line. Therefore, there is no need to separate the tear line forming step and the processing remaining thickness measuring step as in the prior art, and the working time can be effectively shortened.

  In particular, according to the measurement method of the present embodiment, since the distance D between the eddy current sensor 33 and the cutting edge portion 21a of the groove forming member 21 is detected, the cutting edge portion 21a reaching the innermost portion of the groove processing portion 12 is detected. It can be used as a reference, and the processing remaining thickness can be measured with high accuracy.

  In the above-described embodiment, the detection unit 30 (the eddy current sensor 33) is brought into contact with the back surface of the resin member 10 opposite to the tear line forming surface 10a so as not to be separated from the resin member 10. Although arrange | positioned, it is not limited to this, You may arrange | position so that the detection part 30 may space apart from the resin member 10. FIG. However, when the eddy current sensor 33 is arranged so as to be separated from the resin member 10, in the measurement process, after the distance D between the eddy current sensor 33 and the groove forming member 21 is calculated, the eddy current sensor 33 and the resin member 10 are calculated. And the thickness L of the groove processing portion 12 is calculated.

In the embodiment described above, the position of the eddy current sensor 33 is fixed with respect to the resin member 10, but is not limited thereto, and is moved in conjunction with the groove forming member 21 that is linearly moved in the horizontal direction. It is preferable to arrange them as follows.
That is, as shown in FIG. 8, the eddy current sensor 33 is disposed vertically downward with respect to the groove forming member 21 inserted into the resin member 10, and the groove forming member 21 is linearly moved in a substantially horizontal direction. Then, in association with this, the linear position is also moved in the substantially horizontal direction so that the relative position does not fluctuate. In this way, by moving the eddy current sensor 33 in conjunction with the groove forming member 21, the thickness L of the groove processing portion 12 formed at any time as the tear line is formed by the groove forming member 21 can be measured. In addition, the processing remaining thickness of the resin member 10 can be measured in real time over the entire length of the tear line 11, and the product accuracy of the tear line 11 can be improved.

The side view which showed the whole structure of the tear line formation apparatus which concerns on one Example of this invention. The top view of the resin member in which the tear line was formed. Sectional drawing which shows a mode that the thickness of a groove process part is measured in a detection part. The block diagram of a remaining thickness measurement part. The flowchart which shows the procedure which calculates the distance of an eddy current sensor and a groove formation member in a measurement part. The figure showing the output voltage waveform detected in a detecting part. The figure which shows a calculation table. The side view which shows a mode that the thickness of the groove process part in another Example is measured. Sectional drawing which shows a mode that the process remaining thickness of the conventional resin member is measured.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tear line formation apparatus 2 Tear line formation part 3 Remaining thickness measurement part 10 Resin member 10 Tear line formation surface 11 Tear line 12 Groove processing part 21 Groove forming member 21a Cutting edge part 30 Detection part 31 Measurement part 33 Eddy current sensor

Claims (4)

A method for measuring a processing remaining thickness by forming a tear line on a resin member by a groove forming member and measuring a processing remaining thickness of the resin member left by the formation of the tear line,
An eddy current sensor is disposed behind the tear line forming surface of the resin member, and an eddy current is induced in the groove forming member inserted into the resin member by the eddy current sensor, and an output voltage based on the induced eddy current A detection step for detecting
And a measuring step of calculating a residual processing thickness of the resin member by calculating a distance between the eddy current sensor and the groove forming member from the output voltage detected by the detecting step. .   The method for measuring a remaining working thickness according to claim 1, wherein the measuring step measures a distance between the eddy current sensor and a cutting edge portion for forming a tear line formed on the groove forming member.   2. The measuring step includes disposing the eddy current sensor immediately below the groove forming member and moving the eddy current sensor in conjunction with the movement of the groove forming member that is linearly moved in the horizontal direction. Alternatively, the processing thickness measurement method according to claim 2. A processing residual thickness measuring device that forms a tear line on a resin member by a groove forming member and measures a processing residual thickness of the resin member left by the tear line formation,
An eddy current sensor is provided on the back side of the tear line forming surface of the resin member, and an eddy current is induced in the groove forming member inserted into the resin member by the eddy current sensor, based on the induced eddy current. A detector for detecting the output voltage;
A processing residual thickness measuring apparatus comprising: a measuring unit that calculates a processing residual thickness of a resin member by calculating a distance between the eddy current sensor and the groove forming member from an output voltage detected by the detection unit .

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