JP2009156620A - Nondestructive measurement apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nondestructive measurement apparatus, capable of nondestructively measuring the dimensions of a predetermined part of a work piece, in a short time, and capable of enhancing the accuracy of quality evaluation of a product. <P>SOLUTION: The nondestructive measurement apparatus 100 for measuring the dimensions of a predetermined part 55 of the work piece 50, is provided with an X-ray irradiation means 3 for irradiating the work piece 50 with X-rays; a line sensor camera 4 for receiving X-rays having transmitted through the predetermined part of the work piece 50 with photo detectors arranged in a line; and detecting X-ray transmission brightness in line units; and a calculation means 6 for calculating at least the dimension in the X-ray transmission direction at the predetermined part 55, based on the X-ray transmission brightness detected by the sensor camera 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a nondestructive measuring apparatus that measures a dimension of a predetermined part nondestructively, and more particularly to a nondestructive measuring apparatus that performs dimension measurement based on the amount of X-ray transmission.

  The main airbag module for the passenger side of the automobile is housed in the back side of an instrument panel (hereinafter referred to as instrument panel). When the automobile collides, a predetermined signal is transmitted to the airbag module, and the airbag is inflated by the inflator (gas generator). And the predetermined area | region (it is called the fracture | rupture planned part 51) of the instrument panel 50 shown in FIG. 5 is fractured | ruptured by the pressure of the inflated airbag, and it is comprised so that it may expand | deploy to the seat side.

  Conventionally, a lid-like member separate from the main body of the instrument panel 50 is attached to the planned break portion 51 that is released by pressure in the instrument panel 50 when the airbag is deployed. However, since it is not preferable in terms of design, in recent years, the planned fracture portion 51 is formed by directly processing the instrument panel 50 main body.

Specifically, for example, a wavy line groove portion 55 is provided as a dividing line on the back side of the instrument panel along a line shape indicated by a wavy line in the planned break portion 51 of FIG.
As a method of processing the planned fracture portion 51, a blade 54 is projected from the back side of the instrument panel 50 during molding by a molding jig 53 as shown in FIG. 6A, and a cut as shown in the sectional view of FIG. There is an in-mold process for forming a dividing line by putting the (groove portion 55) in a wavy shape on the back of the instrument panel 50.

In the in-mold processing, since the width of the groove portion 55 is narrow as shown in FIG. 6B, it is formed in a deep groove so as to break from the groove portion 55 when the airbag is deployed.
However, when the groove portion 55 is formed as a deep groove as described above, the remaining thickness t of the groove portion becomes a sharp wall thickness with respect to the surrounding wall thickness. Unlike the peripheral portion, the gloss is not preferable in appearance.

In order to solve such a problem, after the instrument panel 50 is molded, a wide groove portion 55 as shown in FIG. 7B is cut by a drill-like blade 56 as shown in FIG. 7A. End mill processing is becoming widespread (see Patent Document 1).
According to this end mill processing, it is not necessary to make the remaining thickness t extremely thin with respect to the surrounding plate thickness, and the heat during processing does not affect the surface side. There is no adverse effect.
JP 2004-141830 A

By the way, as shown in FIG. 8, the groove part 55 formed by this end mill process is formed based on an inspection standard such that the width w, the remaining thickness t, and the joint part d have predetermined dimensions.
That is, a groove dimension inspection standard is provided as an evaluation standard for assuring the product quality of the instrument panel 50. After forming the groove part, for example, the remaining thickness t, width w, and joint part dimension d of the groove part 55 are measured, and all of them are inspected. If it meets the standard value, it will be accepted.

  Of the methods for measuring various dimensions of the groove portion 55, for example, as a method for measuring the remaining thickness w, a stylus-type measuring method in which a needle probe 57 is inserted into the groove portion 55 and the depth thereof is measured as shown in FIG. Alternatively, as shown in FIG. 10, an ultrasonic measurement that measures the remaining thickness t by applying a deep touch element 58 that emits ultrasonic waves from the back side (instrument panel surface side) of the groove portion 55 and analyzing the sound wave data of the reflected waves. There are laws.

  However, in any of the methods, it takes time to measure the dimensions of one groove portion 55, and it takes a very long time to measure all the points of the groove portion 55 composed of several tens of points (for example, 80 points). There was a problem that it took. Therefore, in practice, only one to several groove portions 55 are measured, and there is a problem that product quality cannot be completely guaranteed.

  The present invention has been made under the circumstances as described above, and in a nondestructive measuring apparatus that measures the dimensions of a predetermined part of a workpiece in a nondestructive manner, the dimensions of the predetermined part are measured in a short time, and the product quality An object is to provide a nondestructive measuring apparatus capable of improving the evaluation accuracy.

  In order to solve the above-described problem, a nondestructive measuring apparatus according to the present invention is a nondestructive measuring apparatus that measures a dimension of a predetermined part of a work in a nondestructive manner. Means, a line sensor camera that receives X-rays transmitted through a predetermined part of the workpiece by a light receiving element arranged in a line and detects X-ray transmission luminance in line units, and X-rays detected by the line sensor camera And a calculating means for calculating at least the dimension in the X-ray transmission direction at the predetermined portion based on the transmission luminance.

  The line sensor camera further includes a moving means for moving the work in one direction at a predetermined speed, and the line sensor camera transmits X-rays of X-rays that pass through a predetermined part of the work moved by the moving means. It is preferable that the luminance is detected in units of lines at predetermined time intervals, and the calculation unit calculates the dimension in the moving direction at the predetermined portion based on the X-ray transmission luminance detected by the line sensor camera.

By comprising in this way, dimensions, such as thickness and a width | variety, can be obtained in a short time in the dimension measurement of the predetermined site | part of a workpiece | work.
Therefore, various dimensions can be measured in a short time for all the groove portions in the planned fracture portion, and the product quality evaluation accuracy can be improved.

And a conversion table that records a relationship between a change in thickness of a material forming a predetermined portion of the workpiece and an X-ray transmission luminance corresponding thereto, and the calculation means includes an X-ray transmission detected by the line sensor camera. It is desirable to convert the luminance into a size by referring to the conversion table.
With this configuration, the detected X-ray transmission luminance can be easily converted into dimensions.

The calculation means may output a result of whether or not the size of the predetermined portion of the workpiece is appropriate based on reference value data that is a criterion for determining whether or not the measured size of the predetermined portion is appropriate. desirable.
By comprising in this way, product quality can be immediately evaluated about each workpiece | work which measures.

  According to the present invention, in a non-destructive measuring apparatus that measures a dimension of a predetermined part of a workpiece in a non-destructive manner, the non-destructive measuring apparatus can measure the dimension of the predetermined part in a short time and improve product quality evaluation accuracy. Can be obtained.

Hereinafter, embodiments of a nondestructive measuring apparatus according to the present invention will be described with reference to the drawings.
FIG. 1 is a diagram schematically showing an overall configuration of a nondestructive measuring apparatus according to the present invention. This non-destructive measuring apparatus 100 has various dimensions (remaining thickness t shown in FIG. 8) of a groove portion 55 that forms a planned fracture portion 51 that breaks when an airbag is deployed in an instrument panel (hereinafter referred to as instrument panel) 50 that is a workpiece. , Groove width w, connecting portion d, etc.) and determining whether or not the dimensions satisfy a reference value.

  The nondestructive measuring apparatus 100 includes a belt conveyor 1 as a means for moving a workpiece, and an instrument panel 50 is placed on a circulation drive type conveyor belt 2 included in the belt conveyor 1, and the instrument panel 50 is moved in one direction at a predetermined speed ( The horizontal direction is preferred).

The nondestructive measuring apparatus 1 is fixedly provided above the belt conveyor 1, and is an X-ray source that irradiates a predetermined portion of the instrument panel 50 that moves on the conveyor belt 2, that is, a planned fracture portion 51 with X-rays R. 3 (X-ray irradiation means).
Also provided is a line sensor camera 4 that is fixed below the moving instrument panel 50 and detects the transmission amount (luminance) of the X-rays R that are irradiated from the X-ray source 3 and transmitted through the instrument panel 50.

  That is, a space between the X-ray source 3 that irradiates X-rays in a predetermined direction (preferably vertically downward) and the line sensor camera 4 that receives light in a predetermined direction (preferably vertically upward) is an instrument panel 50 that is a workpiece. Is configured to move at a predetermined speed in one direction (preferably in the horizontal direction) by the belt conveyor 1.

The line sensor camera 4 is a camera in which, for example, thousands of light receiving elements are arranged in a line to form the detection unit 4a, and the X-ray R is received line by line at a predetermined time interval and the light receiving luminance is output. It is made like that.
The space between the X-ray source 3 and the line sensor camera 4 is covered with a shielding box 5 in order to shield light from the outside.

Further, the nondestructive measuring apparatus 100 includes a computer 6 (calculation means) for controlling the driving and operation of the belt conveyor 1, the X-ray source 3, and the line sensor camera 4, and a monitor 7 for displaying the inspection status. Etc.
The computer 6 includes a storage unit 8 in which a measurement program P for obtaining various dimensions of the groove 55 based on the result detected by the line sensor camera 4 is recorded, and a CPU 10 that executes the measurement program P and performs calculations and the like. Have.

  Further, the storage unit 8 stores calibration data 9 (conversion table) used in the dimension calculation by the calculation program P. The calibration data 9 is obtained by using the graph shown in FIG. 3 as a conversion table, in which the relationship of the X-ray transmission amount (luminance) with respect to the thickness change of the resin material forming the instrument panel is recorded in advance.

That is, the size of a predetermined part to be measured is obtained by comparing the X-ray transmission luminance value detected by the line sensor camera 4 with the calibration data 9.
The characteristic conditions such as the wavelength and intensity of the X-ray used when obtaining the calibration data 9 in advance are the same as those of the X-ray R irradiated from the X-ray source 3 to the workpiece (instrument 50). is there.

  Next, an example of a procedure for measuring the dimension of the groove portion 55 of the planned fracture portion 51 in the nondestructive measuring apparatus 1 configured as described above will be described with reference to FIGS. 1 and 2. FIG. 2 is a flowchart showing the flow of processing of the measurement program P executed by the CPU 10 in the computer 6.

First, an instrument panel 50 as a work is placed on the conveyor belt 2 of the belt conveyor 1 in the shielding box 5. Then, the belt conveyor 1 is driven, and the instrument panel 50 starts moving in the horizontal direction on the conveyor belt 2 at a predetermined speed.
When the instrument panel 50 starts to move, X-rays R are irradiated radially from the X-ray source 3 and the instrument panel 50 on the belt 2 moves in the horizontal direction in the emitted X-rays R.

Here, the light reception luminance (X-ray transmission luminance) of the X-ray R that has passed through the planned breakage portion 51 of the instrument panel 50 is detected at predetermined time intervals by the detection unit 4a of the line sensor camera 4, and the computer is used as image data of a plurality of lines. 6 (step S1 in FIG. 2).
In addition, since the detection of the light reception luminance of one line by the line sensor camera 4 is performed instantaneously, the detection of X-rays transmitted through the entire planned fracture portion 51 moving in one direction is performed by performing detection at predetermined time intervals. The brightness detection result can be obtained in a short time.

In the computer 6, the measurement program P is executed, and the size of each groove 55 is obtained by comparing the detected light reception luminance value with the calibration data 9 stored in the storage unit 8 (step S2 in FIG. 2).
In addition, since the fracture | rupture planned part 51 (the groove part 55) moves to one direction in the inside of X-ray R irradiation, and the transmission brightness | luminance detection is performed for every line by the line sensor camera 4, every groove part, Measurement results are obtained in which various dimensions in the vertical direction (X-ray transmission direction) and the horizontal direction (movement direction of the groove portion 55) are obtained, and a three-dimensional measurement model for the groove portion 55 as shown in FIG. 4 is formed. Is obtained.

  Then, in the measurement program P, for each groove portion 55, it is determined whether the remaining thickness t, width w, and connecting portion dimension d of the groove portion 55 as shown in FIG. The result is output to the monitor 7 (steps S4 and S5 in FIG. 2).

As described above, according to the embodiment of the present invention, X-ray R is irradiated to the workpiece (the planned breakage portion 51 of the instrument panel 50), the amount of transmission is received by the line sensor camera 4, and the received light intensity is increased. By performing dimension conversion based on the calibration data 9, the remaining thickness t and the like (dimension in the X-ray transmission direction) related to the groove 55 shown in FIG. 8 can be obtained instantaneously.
Further, in order to detect the transmission amount of the X-ray R at every predetermined time interval by the line sensor camera 4 while moving the workpiece in one direction at a predetermined speed by the belt conveyor 1 with respect to the line sensor camera 4, FIG. Further, the width dimension w, the joint dimension d and the like (dimension in the moving direction of the groove part 55) related to the groove part 55 can be obtained in a short time.
Therefore, by using the nondestructive measuring apparatus 100 according to the present invention, it is possible to measure various dimensions of all the groove portions 55 in the planned fracture portion 51 in a short time, and to improve the product quality evaluation accuracy.

  In the above-described embodiment, an example in which the measurement is performed on the groove portion 55 of the planned fracture portion 51 in the instrument panel 50 has been shown. However, the nondestructive measurement apparatus 100 of the present invention is not limited to the measurement target, and requires measurement. It can also be used for measuring other measuring objects having a large number of locations.

  In the embodiment, the instrument panel 50 moving in the lateral direction by the belt conveyor 1 is irradiated with X-rays from above to below, and the X-ray transmission luminance is detected by the line sensor camera 4 below. However, in the present invention, the arrangement of these components is not limited, and other arrangement forms may be adopted as long as the relative relationship between the components can be maintained.

  The present invention relates to a nondestructive measuring device that measures a dimension of a predetermined part nondestructively, and can be suitably used, for example, in an automobile parts manufacturing industry.

FIG. 1 is a diagram schematically showing an overall configuration of a nondestructive measuring apparatus according to the present invention. FIG. 2 is a flow showing a flow of processing of a measurement program executed in a computer included in the nondestructive measurement apparatus of FIG. FIG. 3 is a graph showing the relationship of the amount of X-ray transmission (luminance) with respect to the thickness change of the resin material forming the instrument panel. FIG. 4 is a three-dimensional measurement model for the groove portion obtained from the measurement result. FIG. 5 is a view showing an instrument panel and a planned fracture portion thereof. FIG. 6 is a diagram for explaining in-mold machining. FIG. 7 is a diagram for explaining end milling. FIG. 8 is a diagram showing a measurement site where an inspection standard is provided in the groove. FIG. 9 is a diagram for explaining the remaining thickness measurement by the stylus measurement method. FIG. 10 is a diagram for explaining the remaining thickness measurement by the ultrasonic measurement method.

Explanation of symbols

1 Belt conveyor (moving means)
2 Conveyor belt 3 X-ray source (X-ray irradiation means)
4 line sensor camera 4a detector 5 shielding box 6 computer (calculation means)
7 Monitor 8 Storage unit 9 Calibration data (conversion table)
10 CPU
100 Nondestructive measuring device P Measurement program

Claims (4)

In a non-destructive measuring device that measures the dimensions of a given part of a workpiece non-destructively,
X-ray irradiation means for irradiating the workpiece with X-rays;
A line sensor camera that receives X-rays transmitted through a predetermined portion of the workpiece with a light receiving element arranged in a line, and detects X-ray transmission luminance in units of lines;
A nondestructive measuring apparatus comprising: a calculation unit that calculates at least a dimension in the X-ray transmission direction at the predetermined portion based on the X-ray transmission luminance detected by the line sensor camera. A moving means for moving the workpiece in one direction at a predetermined speed with respect to the line sensor camera,
The line sensor camera detects the X-ray transmission luminance of X-rays transmitted through a predetermined part of the workpiece moved by the moving means in units of lines at predetermined time intervals,
The nondestructive measuring apparatus according to claim 1, wherein the calculating unit calculates a dimension in a moving direction at the predetermined portion based on an X-ray transmission luminance detected by the line sensor camera. A conversion table that records the relationship between the change in the thickness of the material forming the predetermined part of the workpiece and the X-ray transmission luminance corresponding thereto;
The non-destructive measuring apparatus according to claim 1, wherein the calculation unit converts the X-ray transmission luminance detected by the line sensor camera into a size by referring to the conversion table. .   The calculation means outputs a result as to whether or not the dimension of the predetermined part of the workpiece is appropriate based on reference value data serving as a criterion for determining whether or not the measured dimension of the predetermined part is appropriate. The nondestructive measuring device according to any one of claims 1 to 3.

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