JPS6155041B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus and method for measuring the external shape of an object to be measured, such as an optical fiber, having a rotationally symmetrical external shape.

The optical fiber has a diameter of about 100 to 200 μ (0.1 to 0.2 mm), and has a core of about 20 to 60 μ inside. Since these are attached to eccentric connectors, etc., their dimensional accuracy must be approximately 3 μm or less. Conventionally, such concentric or eccentric circles have been measured optically using a projector or a microscope.

When measuring the amount of deviation between the center axis of another rotationally symmetrical shape included in the measurement surface of an object to be measured whose outer shape is rotationally symmetrical, such as an optical fiber, and the central axis of the outer shape of the object to be measured, a projector is used.・It is almost impossible to make reliable measurements below the micron level using methods such as optical measurement using a microscope. The resolution of the human eye is approximately 0.1 mm, and the resolution of an optical microscope is also possible down to approximately 0.15 to 0.25 microns, although there is a diffraction phenomenon due to the wave nature of light. Therefore, theoretically, even if the magnification of an optical microscope is increased to a maximum of 1000 times, it would be possible to read and identify the information necessary for measurement, but this is not practical.

The reason for this is that when performing highly accurate measurements by increasing the measurement magnification, there are various problems as described below.

(1) It is difficult to produce a high-magnification lens with a deep depth of focus. Therefore, the smoothness of the surface of the object to be measured,
Sharpness of the end face is even more required. In particular, when the end face of the object to be measured is chamfered, etc., it becomes impossible to capture the external end face within the same depth of focus as the measurement surface, which takes a considerable amount of time for measurement. In addition, factors that cause measurement errors, such as instrumental differences due to the measuring equipment itself and individual errors during reading, also increase.

(2) As the observation field of view becomes narrower, it becomes difficult to find the measurement position, and this work increases the difference between measuring instruments.
This leads to deterioration of workability.

(3) Become more susceptible to the effects of surrounding vibrations.

(4) It is extremely difficult to perform highly reliable and highly accurate measurements using these methods, and at the same time, it is extremely taxing on the observer's eyes and nerves, making it difficult to continue the measurement process for long periods of time. In addition, in the case of concentricity measurement, it is also possible to use a roundness measuring machine using a stylus, but in this case the shape of the object to be measured is
It is not possible to measure objects on the same plane as shown in the figure.
Only limited objects such as hollow pipe shapes can be measured.

The object of the present invention is to measure the center axis of another rotationally symmetrical shape included in the measurement surface of a workpiece whose external shape has a rotationally symmetrical shape, which has been difficult to measure with high precision in the past, and the central axis of the external shape of the workpiece. An object of the present invention is to provide a device and a method for measuring the amount of deviation of an effective reading value with an accuracy of microns.

The present invention is a measuring device and method that combines both an optical measuring device and a contact measuring device.In order to cover the weak points of the optical measuring system at high magnification, a microscope and a television camera are connected and a video monitor screen is used. The contact measurement system has a recording display section that displays the position of the measurement point at the center of the recording display section, and the position of the measurement point is displayed at the center of the display section. The position of the external shape is displayed in analog form.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a configuration diagram of a measuring device according to an embodiment of the present invention, in which 1 is an object to be measured, 2 is a rotary table, 3 is a microscope, 4 is a television camera, 5 is a camera control device,
6 is a video monitor, 7 is a detector, 8 is a feeding device,
9 is an amplifier, 10 is a recording display device, 11 is an XY
It is a fine movement table.

In this measuring device, first, the first center axis of the object to be measured (for example, an optical fiber) 1 is aligned with the rotation center axis of the rotary table 2 using the XY fine movement table 11 while watching the video monitor 6. . Thereafter, the contact type detector 7 is brought into contact with the object to be measured, the rotary table 2 is rotated, and the amount of displacement of the outer shape of the object to be measured is detected. This contact type detector 7 has a contact point such as a needle, and detects the position by connecting the movement of the contact point to a movable iron core or the like and converting it into an electric signal. The signal from the detector 7 is sent to the amplifier 9 together with the sending device signal and displayed in analog form on the recording/display device 10. The first central axis of the object to be measured 1 is determined by this analog display.

Next, the second central axis of another rotationally symmetrical shape (for example, the core of an optical fiber) included in the measurement surface of the object to be measured 1 is determined in the same manner as described above, and the deviation from the first central axis is determined. Measure the concentricity.

FIG. 2 is a block diagram of a measuring device according to another embodiment of the present invention, in which 13 is an automatic centripetal device, 14 is a changeover switch, and the other components are the same as in FIG. 1.
In this case, the measurement method is as follows:
While looking at the video monitor 6, the XY fine movement table 11
to match the rotation center axis of the rotary table 2. Thereafter, the contact type detector 7 is brought into contact with the object to be measured, the rotary table 2 is rotated, and the amount of displacement of the outer shape of the object to be measured is detected. When the switch 14 is as shown in the figure, the external shape of the object to be measured is displayed in analog on the display section 11 at the same time as shown in FIG. Concentricity is measured by measuring the amount of deviation from the axis. Further, when the changeover switch 14 is switched to the opposite side as shown in the figure, the value to be determined is digitally displayed on the recording display device 11 via the automatic centripetal device 13. This automatic centripetal device 13 determines the position of the center axis of the outer shape of the object to be measured through numerical analysis, and automatically calculates the amount of deviation from the center axis of the rotationally symmetrical shape included in the measurement surface of the object. This is a device that performs digital calculations and is manufactured by Kosaka Research Institute Co., Ltd.

The features of this device with such a configuration are as follows: (1) By taking advantage of the advantages of both optical measurement method and contact measurement method, it is possible to measure the shape of the object to be measured, which previously could not be measured with high precision. Concentricity can be easily measured.

(2) In order to align the center axis of the rotationally symmetrical shape included in the measurement surface of the object with high precision with the center axis of the rotary table, high-magnification measurement is required.
At this time, not only the microscope but also the television camera 4 is used to magnify the image to be measured, which alleviates the problem of the depth of focus of the lens and enables observation in a wide field of view, significantly improving work efficiency.

(3) Even if the end face of the object to be measured is chamfered, has burrs, sag, etc., the end face can be easily captured by using a contact type detector, making it suitable for optical measurement. Measurement accuracy is significantly improved.

(4) Since the center axis of the rotationally symmetrical shape included in the measurement surface of the object to be measured can be precisely aligned with the center axis of the rotating table, 1. Rotating the object to be measured on the rotating table,
By simply detecting and processing the amount of displacement of the external shape from a contact detector located at a fixed position, the external shape of the measured object can be determined with the center axis of the rotationally symmetrical shape included in the measurement surface of the measured object as the center of the display. It can be easily determined using analog display.

2 Rotate the object to be measured on the rotary table,
The amount of displacement of the external shape is detected and processed by a contact detector located at a fixed position, the position of the central axis of the external shape of the object to be measured is determined by numerical analysis, and the rotation included in the measurement surface of the object to be measured is determined by numerical analysis. By using an automatic centripetal device that automatically determines the amount of deviation from the central axis of a symmetrical shape, concentricity can be displayed digitally, making it extremely easy to measure concentricity.

[Brief explanation of the drawing]

FIGS. 1 and 2 are block diagrams of external shape measuring devices according to first and second embodiments of the present invention, and FIGS.
FIG. 5 is a perspective view of an example of the shape of the object to be measured. In the figure: 1...Object to be measured, 2...Rotary table, 3...Microscope, 4...TV camera, 5...Camera control device, 6
...video monitor, 7...detector, 8...feeding device, 9
. . . amplifier device, 10 . . . recording display device, 11 .

Claims (1)

[Scope of Claims] 1. A rotary table on which a workpiece having a rotationally symmetrical outer shape is placed, and a rotary table provided on the rotary table and with a central axis of the rotary table aligned with a first central axis of the workpiece or the a moving mechanism capable of moving and adjusting a second central axis of another rotationally symmetrical shape within an end surface of the object to be measured; a light monitoring means capable of optically magnifying and observing an image of the end surface of the object to be measured; and the object to be measured. and a display means for displaying the output of the contact detection means, and displays the outer shape of the object to be measured on the display means by rotating the rotary table. An external shape measuring device characterized by measuring a deviation between the first and second central axes. 2. In a method for measuring the outer shape of a workpiece whose outer shape has a rotationally symmetrical shape, while optically enlarging and observing an image of an end face of the workpiece placed on a rotary table, a central axis and a second central axis of another rotationally symmetrical shape within the end surface are respectively aligned with the central axis of the rotary table;
An external shape measuring method, characterized in that the deviation between the first and second central axes is measured by detecting and displaying the external shapes of the object to be measured using external contactors while rotating the rotary table.