JPS5847203A - Device for measuring a sectional configuration of an object with uneven surface - Google Patents

Abstract

PURPOSE:To enable measurement of a shape of an object without a probe being caught in the uneven surface of the object by means of a structure wherein a probe movable in contact with the surface of an object under measurement is raised at a certain interval and a lower peak value of the probe's locus per interval is electrically output, said peak value being magnified and recorded. CONSTITUTION:The probe 11 with its radius of about 2mm. is movable cross-wise in accordance with the shape of the object under measurement. Another probe 9 with a sharpened end is connected to a raising string 15 which is securted to an oscillator 19 via a pulley 17. By turning the eccentric axis of the oscillator 19 by means of a motor 18, the probe 9 is cyclically raised by the oscillator 19 in the vertical direction so that fine unevenness of the surface of the object can be measured without the probe being caught in the unevenness. Also, the lower peak value of the probe's locus per interval is electrically output and is magnified and recorded whereby fine variation in surface level can be scribed out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for drawing a cross-sectional shape of a three-dimensional object having an irregular surface shape into a two-dimensional figure.

Conventionally, methods for measuring the cross-sectional shape of a three-dimensional object with an irregular surface shape include (1) making a shape with silicone rubber, etc., and observing the cut surface of the obtained shape with a projector, etc. Method. (2) A method in which the needle is brought into contact with the surface of an object with a needle pressure of several grams, and the needle is automatically fed to record the movement trajectory of the needle tip. (3) The worker traces the surface of the object with a stylus,
There is a method of recording the movement trajectory of the stylus using a detector that operates in conjunction with the stylus.

Method (1) above does not allow automatic measurement.

The exact location of the cross section to be measured cannot be determined.

When the cross section is flat and large, the focal point differs depending on the location on the projection surface, so the image becomes uneven, and the cross-sectional shape is difficult for the measurer to see because the image is clearly visible to the human eye. There are different drawbacks. The second method has the disadvantage that the needle gets caught in areas where the surface of the object to be measured is severely uneven, making it impossible to measure. In addition, method (3) is a method that mainly measures surface shapes with thick ridges, and %o mi! j
It does not have a resolution of meters or higher, requires a worker to scrape the surface, and has the drawback of not being able to measure automatically.

The present invention solves the above-mentioned drawbacks, and provides an apparatus that prevents the stylus from getting caught on the surface of an object and that can accurately and easily draw an image of the cross-sectional shape of an object having a highly uneven surface. be.

Figure 2-1 is a partial vertical sectional view of the
2 shows its side view, and FIGS. 2-3 show its plan view.

Reference numeral 1 denotes an object to be measured, which is fixed by a fixing vise 2. Reference numeral 3 denotes a movable table for horizontally moving the measuring instrument, which is moved in the horizontal direction by attaching a pulley to the driving motor 4 and winding the driving wire 5 around the pulley several times and fixing both ends. The amount of lateral movement is determined by winding the wire 6 for lateral position detection several times around a pulley attached to the end of the variable resistor 7 for lateral position detection and fixing both ends. The voltage changes as the voltage changes.

A measuring device main body 8 is mounted on the movable table main body 3, and a stylus attached to the measuring device main body 8 scans the surface of the object to be measured 1, and determines the vertical position of the surface of the object to be measured. Detect. These vertical and horizontal positions are recorded as a cross-sectional shape at an arbitrary magnification on an X-Y recorder. '8. Automatic analysis of the cross-sectional shape can be performed by converting the vertical and horizontal electrical signals into widths, inputting them into an electronic h1 calculator, and performing image processing.

Next, the main body of the measuring instrument will be explained with reference to FIG. 2. The main body of the measuring instrument is equipped with two stylus probes that scan the object to be measured. The tip radius of the stylus 11 is approximately 2W, and it moves in the lateral direction following thick ridges and undulations, ignoring the fine irregularities of the object to be measured. The stylus 11 is attached below the column 12, and a pulley 13 is attached above the column 12. The other stylus 9 has a tip radius of approximately 20 μm.
It has a sharp tip and scans fine irregularities on the surface of the object to be measured. Then, the stylus 9 is connected to the lifting moonlight 15 hanging down from the support 14 fixed to the main body of the measuring instrument.
The pulled moonlight 15 passes through a pulley 17 fixed above the stylus 9 and is fixed to a °C vibrator 19.

The vibrator 19 is vibrated by rotating an eccentric shaft by a motor 18, and the pulling strength can be easily adjusted by simply changing the distance from the center. Therefore, the stylus 9 is periodically pulled up in the vertical direction by the vibrator 19, thereby making it possible to measure even minute and steep unevenness changes without getting stuck.

The amount by which the stylus 9 is pulled up is determined by the action of the strut 12 and pulley 13 that are interlocked with the stylus 9. The amplitude approaches the amplitude of the vibrator 19 at steep rise points, and decreases at flat locations. Therefore, if the inertial force due to the periodic vertical movement of the stylus 9 is larger than necessary, the differential transformer core 20 is disposed between the pulley 16 and the vertical position of the stylus 9 is moved too high. Detection is performed using a differential transformer 21 of high power.

Figure 3 is a diagram showing the electrical signals at each location. Line A is the vertical direction output signal of the stylus 9 and the horizontal direction output signal of the movable table main body 3 magnified several tens of times. Line B is magnified to the same magnification as line A (by a projector). Comparing the two, in 1llA, the amplitude appears to be large at steep slopes and small at flat areas. The waveform obtained by the peak detector 22 from the lower peak of each cycle of the waveform as shown by line A is a stepped waveform as shown in 11iiC. The height and width of this step are both several tens of micrometers.
Since it is before and after, it is ignored on the X-Y L/coder and a curve similar to the measurement cross section is drawn. Also, each row of X-
Curves can be easily analyzed by inputting the Y coordinate table into a computer.

The curve drawn using this device and the silicone rubber template were enlarged 20 times using a projector, and 0.5
The curves drawn using lines with a thickness of 1111 matched within the range of line thickness.

Note that instead of the automatic lateral feeding mechanism in the above device, a method using a screw, a method using a rack and a pinion, a method using a hydraulic cylinder, etc. may be used. Although a variable resistor with high resolution and good linearity was used to detect the lateral position, a Magnescale or a differential transformer cap can be used instead.

゛Furthermore, the vibration exciter is not a mechanical one, but may be performed using a Macnet, pneumatic pressure, hydraulic pressure, or the like.

Furthermore, in order to adjust the amplitude of the vibrator, a stylus 11 with a large tip radius is installed. It is also possible to use a mechanism that gives an additional deviation to the lower peak value, that is, a deviation in the amount of lifting.

According to the measuring device of the present invention, there is no drawback that an accurate illumination constant value cannot be obtained due to the stylus being drawn to a steeply rising part as in conventional devices, and the molten hook can be maintained at a constant temperature even when the object to be measured has complex irregularities. By pulling up the stylus at a period of 1
This does not occur and accurate measurement values can be obtained. In addition, since the lower peak value of the trajectory of the stylus light is electrically extracted for each period, and it is magnified and recorded, it is possible to accurately depict even subtle irregularities, and the curves drawn For example, by directly inputting electrical signals into a computer, analysis has the advantage of being able to perform accurate image processing with fewer errors caused by human vision.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an overview of the entire measuring device of the present invention, Fig. 2 shows the main body of the measuring device, Fig. 2-1 is a partial vertical sectional view thereof, and Fig. 2-2 is a side view thereof. 2-3 are plan views thereof, and FIG. 3 is a diagram showing electrical signals at various locations on the object to be measured. 1: Object to be measured 2: Fixing vise 3: Moving table
4: Drive motor 5: Drive wire 6: Position detection wire 7: Variable resistor 8: Measuring instrument body 9: 11: Stylus 10: X-Y recorder 12: 1
4: Strut 13: 16:17: Pulley 15: Thread for pulling up the stylus 18: Vibrator drive motor 19: Vibrator 20: Core for differential transformer 21: Differential transformer A line: Differential transformer up Output and lateral signal curve B line 2 curves obtained from the C line 2 peak detector output signal Diagram D: Enlarged view of doubled signal lateral direction Patent applicant Director, National Institute of Metals and Materials Technology, Science and Technology Agency 9-2 Figure 2-3

Claims (1)

[Claims] A stylus that moves in contact with the surface of the object to be measured is configured to be pulled up at regular intervals, and has means for electrically extracting the lower peak value for each period of the locus of the tip of the stylus, 1. A measuring device for measuring the cross-sectional shape of an object having an irregular surface shape, characterized in that it is configured to magnify and record a value.