KR20010070792A - Optical measuring instrument for lathe - Google Patents

Abstract

PURPOSE: An optical precise measurement device for a lathe is provided to measure the state of a lathe for simplifying the amendment for self-errors of the lathe and simultaneously measure an outer diameter, a length, a concentricity, a straightness and the like of an object to process with high precision, thereby minimizing the measurement errors and the measurement and processing time periods. CONSTITUTION: An optical precise measurement device for a lathe includes a detachable camera part formed of a lens(5) and a CCD camera module(6) for outputting an image signal of an image of a rotating or stopped object, a fixing die for fixing the camera, a monitor part having an exclusive monitor(8) and a hardware main body(7) having an image processing part for processing the image signal transmitted from the camera part or input numeral values for obtaining an outer diameter, a length, a concentricity, straightness and the like of the object, numeral and directional keys, and ports for data input and output, and a setting-bar for initiating the device.

Description

Lathe optical precision meter {OPTICAL MEASURING INSTRUMENT FOR LATHE}

There was no way for the operator to accurately and easily grasp the state including the error range of self-processing such as general-purpose lathe or CNC lathe. Therefore, it becomes difficult to perform various corrections performed on the lathe itself to reduce the processing error itself, and the time required for measurement or inspection during processing or completion of processing increases.

In the case of general-purpose lathes, in order to measure the workpiece during or after completion, the operator or inspector measures the length using a vernier caliper, the outer diameter is micrometer, and the concentricity and straightness are dial gauges. These measuring instruments usually have their own measurement errors in the unit of μm, and measurement values are different depending on the operator, inspector, or even the same operator depending on the measurement site, measurement time and location. It is easy to be in the unit of μm, and the possibility of error is increased by applying the local measured value to the whole. In addition, these measuring instruments have a larger error than the initial error depending on the period of use, frequency of use, and method of use.

In the case of CNC lathes, the accuracy of machining is increased by measuring the dimensions of the workpiece using the touch sensor attached to the tool post, automatically correcting the difference from the target value, and correcting the machining dimension for the next machining. However, the touch type touch sensor has a limited lifespan and has a measurement error due to wear and the like. Therefore, the touch sensor is used by measuring equipment used in general-purpose lathes during or after processing.

This error of the lathe itself and the error of the measuring equipment not only makes it difficult to precise machining, but also becomes an important factor to increase the working time even in the case of inaccurate workpieces.

In order to solve this problem, it is necessary to measure the state of the shelf, a measuring device having a small measurement error, a short measuring time, and a wide measuring range is required.

To this end, the present invention obtains an image of a SETTING-BAR or a workpiece that is stationary or rotated from an image signal input unit (also known as a CCD camera) consisting of a lens and a CCD element board, extracts contour information of an object, and creates three-dimensional dimension information. By analyzing this, the state information of the lathe and various dimension information (outer diameter, length, concentricity, straightness, etc.) of the workpiece are output to the screen and the printer.

According to the present invention, the measurement accuracy varies depending on the size of an object according to the number of pixels of a CCD device (aka imaging device) used, and generally has an accuracy of about 1 μm and uses an AUTO IRIS LENS (automatic adjustment lens). In this case, it is possible to measure nm.

1 is a block diagram of the present invention

2 is a hardware block diagram according to an embodiment of the present invention.

Figure 3 is an installation example according to an embodiment of the present invention

Figure 4 is a shape diagram of the SETTING-BAR according to an embodiment of the present invention

5 is a hardware block diagram according to another embodiment of the present invention.

6 is a hardware block diagram according to another embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

9: Headstock 10: CHUCK 11: JAW

12: shuttle 13: tailstock 14: bed

15: monitor unit holder 16: monitor unit

17: camera unit holder 18, 20: SETTING-BAR

19: camera unit 23, 30: PC body

24, 31: PC monitor 25, 32: Printer

The configuration of the present invention for achieving the above object is largely composed of the lens 1 of FIG. 1, the image signal input unit 2, the image processing unit 3, the output unit 4 and the SETTING-BAR 20 of FIG. Will be divided. 2, the image signal input unit 2 is a CCD camera module 6, the image processing unit 3 is a dedicated hardware main body 7 including numerals and direction keys, and the output unit 4 is a dedicated monitor. This corresponds to (8).

The lens 1 may use a general lens having a fixed magnification and an AUTO IRIS LENS (autoadjusting lens) whose magnification is automatically adjusted.

The video signal input unit 2 is composed of a CCD camera module 6 which signals an image of a set-bar or a workpiece being stopped or rotated, depending on the number of pixels of the CCD image sensor included in the CCD camera module 6. The measurement accuracy will be different.

The image processor 3 receives an image signal from the image input unit 2 to capture a still image when the object is still, and to obtain 360-degree image information evenly according to the measured rotation speed during rotation. By dividing the rotation speed by 360 degrees, the capture speed and the number of captures are calculated and captured according to the capture speed and the number of captures. At this time, the method of measuring the rotational speed is to attach a round sticker (not necessarily circular) to the outer diameter of the groove of the CHUCK (10) where an arbitrary JAW (11) is mounted. The rotation speed is calculated by calculating the time and the position on the captured image.

The contour is extracted from the captured image, and only the information of the SETTING-BAR (18) or the workpiece (hereinafter referred to as object) is extracted from the extracted contour except for the main shaft (9), CHUCK (10), and JAW (11). . The contour information of the extracted object is applied to a correction variable for correcting the distortion of the CCD and the image pickup device included in the CCD camera module 6, and according to the size of the object in space and the distance between the object and the CCD camera. Calculate by applying the spatial variable to match the length in the 2D image with the actual. The calculated results are three-dimensionally combined into data such as dimensions and tolerance ranges for each part, maximum and minimum dimensions, and determination of the sum. The above is a case of using a general lens with a fixed magnification. When using an AUTO IRIS LENS which automatically adjusts the magnification, the magnification is determined according to a magnification variable representing the ratio of the measurement part of the object in the input image. It is to be calculated by applying the scaling factor to adjust the spatial variable depending on the magnification.

The output unit 4 outputs the screened information on the monitor 8 according to the option selected by the user.

3 is an installation example according to an embodiment of such an optical precision measuring instrument for the shelf, the camera unit 19 consisting of the lens 5 and the CCD camera module 6 is the degree of measurement of the object varies depending on the installation position 3 may be provided at the front or rear side of the right side of the carriage 12, or may be installed at the front, rear right side of the bed 14, the upper tailstock 13, or the like. To this end, the mounting shape of the camera unit holder 17 is varied according to the shape of the mounting target, and is divided into a fixed stationary and an adjustable stationary for fixing the position of the camera unit. In addition, the camera unit is divided into a fixed type that is fixed to the holder and a fixed type that can be rotated 90 degrees on the rear plane of the camera part in the state fixed to the holder, a rotating type using a stepping motor to adjust the rotation angle.

The camera unit 19 is a detachable type that is easily detachable from the camera unit holder 17.

The monitor unit 16 includes a dedicated monitor 8 and a dedicated hardware main body 7, and in the case of a dedicated hardware main body, may be installed separately from the dedicated monitor 8. The installation position is a location that is easy for the worker to see during the work, so long as it does not interfere with the work.

Using the SETTING-BAR 20 of FIG. 4, the optical precision measuring instrument for the shelf may be initialized or the state of the shelf may be determined.

The procedure for initializing the lathe optical precision meter is as follows.

After installing the optical precision measuring instrument for the shelf, it is necessary to input dimensions such as the outer diameter and the length of the SETTING-BAR 20, and do not need to input the subsequent initialization. After capturing the precision-set SET-BAR (20), capture the still image, extract the contour information of the SET-BAR (20), compare it with the input dimensions, calculate the spatial variable, and rotate the SET-BAR (20). The initializing is completed when the obtained dimension information is within the tolerance range compared with the input dimension. The above is the case of using the fixed lens and the fixed camera unit. When using the AUTO IRIS LENS (auto-adjusting lens), the magnification is automatically adjusted. The task of capturing the spatial variables by capturing them, analyzing them, or combining them will be added. In addition, in the case of using the adjustable camera unit, it is necessary to additionally obtain the spatial variable after rotating 90 degrees, and in the case of using the rotating camera unit, the spatial variable according to the rotation angle should be obtained and analyzed or combined with this to obtain additional rotational variables.

The status of the lathe is captured by the setting speed and the number of captures obtained by CHUCKING and rotating the SETTING-BAR (20), and after contouring the captured image information, it is analyzed and analyzed by SETTING-BAR (20) centerline and rotation. The slope value of the center line of the SETTING-BAR (20) with respect to the center of rotation of the center line and the intersection point of the center line of the center of the SETTING-BAR (20) with respect to the center line of the center line obtained from the primary function and the reference position of the center line are output.

If the shelf needs to be calibrated, the necessity of the calibration is displayed with a beeping sound. If you want to calibrate, select the calibration mode to process the old image processing information or the new image information, and then, at the angle and the angle of the radial correction position. Information such as the rotation center to be corrected and the tilt of the SET-BAR 20 is calculated and displayed on the screen.

If you input the design dimension and tolerance of the machined part before or during machining, you can analyze the inclination and intersection point of the workpiece centerline with respect to the center of rotation when calculating the machining dimension during machining. If there is a need for correction, a warning signal is displayed on the screen together with a beeping sound. When the correction mode is selected, the following process is performed in the same manner as the above correction mode selection.

As shown in FIG. 5, the optical precision measuring instrument for the lathe uses the camera unit consisting of the lens 21 and the CCD camera module 22 as shown in FIG. 4) can be a PC monitor 24. In addition, as shown in FIG. 5, the printer 25 may be connected to the PC main body 23 to output a measurement result, inspection sheet, and the like. Such a printer 25 may be connected to the dedicated hardware body 7 of FIG.

As shown in FIG. 6, one or more optical precision measuring instruments for the shelf as shown in FIG. 2 may be connected to the PC main body 30 to output the screen to the PC monitor 31 or may be printed through the printer 32. In addition, depending on the performance and purpose of the PC main body can be used as shown in Figure 6 by connecting several camera units to the PC main body 23 of FIG. At this time, the camera unit includes a case where one or more units are installed on the same shelf.

According to the embodiment of the present invention as described above it is possible to measure the state of the shelf it is easy to correct the self error of the shelf, it is possible to simultaneously measure the outer diameter, length, concentricity and straightness of the workpiece. In addition, the measurement accuracy is high, the measurement error is minimized, and the measurement time and processing time are minimized. In addition, it is possible to make data such as inspection sheet, which reduces the time required for inspection after completion of processing.

Claims (8)

A detachable camera unit comprising a lens and a CCD camera module for outputting an image of an object in a stationary or rotating state as an image signal; A holder for fixing the camera unit; A hardware main body including an image processing unit for processing dimensions of an image signal or an input value transmitted from a camera unit to obtain dimensions of an outer diameter, length, concentricity, straightness, etc., a port for inputting and outputting numbers, direction keys, and data; A monitor unit comprising the hardware main body and a monitor for outputting the obtained result; A fixture for fixing it; Lathe optical precision measuring instrument including SETTING-BAR required for initialization. The method of claim 1, Obtaining and applying correction parameters for correcting distortion of the lens and the CCD; Enter the dimensions of the SETTING-BAR and obtain the contour by capturing still images with the SETTING-BAR CHUCKING, and compare the input SETTING-BAR dimensions with the dimensions of the contour to match the dimensions on the captured image with the actual dimensions. Calculating, applying, and applying a spatial variable to make it appear; A circular sticker (not necessarily circular) is attached to the circumference of CHUCK's groove where an arbitrary JAW is mounted, and the rotation speed is calculated by calculating the time taken for the sticker to be captured continuously and the position on the captured image. Method; Determining a capture rate and the number of captures by dividing the rotational speed by 360 degrees to obtain 360-degree image information; Capture the image according to the capture speed and the number of captures obtained by rotating the chucking set-bar, outline the captured image information, analyze it, and then obtain the rotation obtained by angle from the first function and the reference position of the set-bar center line and rotation center line. A method of calculating the inclination value of the center line of the SETTING-BAR with respect to the center line, the value of the intersection of the center line of the SETTING-BAR and the center of rotation; If the shelf needs to be calibrated, the necessity of the calibration is displayed with a beep, and if you want to calibrate, select the calibration mode to select the angle of the radial calibration position, the center of rotation to be calibrated at that angle, and the tilt of the setting bar. A configuration and method, including a method for calculating and displaying information. The method of claim 1 A method of obtaining a rotational speed and a method of rotating the workpiece while the workpiece is being processed or finished; Obtaining a capture speed and the number of captures using the rotation speed; Extracting only information of an object by contouring the captured image according to the capture speed and the number of captures; A method for calculating by applying a correction variable, a spatial variable, etc. to the contour information of the object; A method of three-dimensionally combining the results of the calculation and data outputting the information such as the dimension and tolerance range for each part, the maximum dimension part, the minimum dimension part, and the joint decision; On-screen warning of the necessity of correction in case of deviation from the tolerance or the possibility of deviation from the tolerance by comparing and analyzing the dimensions of the workpiece and the design dimensions and tolerances of the machined part entered before or during machining. How to; A method of outputting numerical information necessary for correction when selecting a correction mode; A method of outputting the screen together with the processing completion beep if the dimension of the workpiece is within the allowable range of the design dimension of the inputted part; Its configuration and method comprising a selection mode capable of selectively performing the above methods. The principle of claim 1 is the same, A detachable camera unit comprising a lens and a CCD camera module to output an image of an object as an image signal; A holder for fixing the camera unit; A general PC comprising a PC main body and a monitor in which an image processing unit is installed; Lathe optical precision meter with SETTING-BAR required for initialization. The principle of claim 1 is the same, In case of using AUTO IRIS LENS (auto-adjusting lens), in which the magnification is adjusted automatically instead of the fixed lens, the magnification is adjusted according to the scaling factor representing the ratio of the measurement part of the object in the input image. Obtaining a magnification variable for adjusting the spatial variable depending on the magnification; Applying a magnification variable to perform the operation of claim 2; A composition and method comprising a method of performing the task of claim 3 by applying a scaling factor. The principle of claim 1 is the same, An adjustable camera portion capable of rotating 90 degrees on the rear portion of the camera portion; A method of performing the task of claim 2 by applying a spatial variable according to a 90 degree rotation; A composition and method comprising the method of performing the task of claim 3 by applying a spatial variable according to a 90 degree rotation. In claim 6, A rotatable camera portion for freely adjusting the rotation angle using a stepping motor on the rear portion of the camera portion; A method of controlling the rotation angle and speed of the stepping motor; Obtaining a rotational space variable according to an arbitrary rotation; A method of performing the task of claim 2 by applying a rotational space variable; A composition and method comprising a method of performing the task of claim 3 by applying a rotational space variable. The same principle as in paragraph 1 At least one optical precision measuring instrument for lathe according to claim 1; The method and configuration including a general PC consisting of a PC main body and a monitor with a program installed to combine, analyze and data the information from one or more shelf optical precision measuring instrument.