JPH0758168B2 - Dimension measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application of the Present Invention> The present invention provides a dimension of an object to be measured having at least two or more plate portions that are formed to face each other with a gap so as to be orthogonal to one axis. The present invention relates to a dimension measuring device for measuring.

<Prior Art> (FIGS. 7 to 8) For example, in order to accelerate and control electrons in a television picture tube, as shown in FIG. 7, a plurality of plate-shaped grids 1, 1, ...
Are arranged in parallel on one axis at predetermined intervals, and the electron gun 3 formed by being connected by the connecting plates 2 and 2 is attached.

In such an electron gun 3, unless the interval between the grids 1, 1, ... Is set to a predetermined dimension, the image quality of the television picture tube is significantly deteriorated. In such cases, the measurement and management of the dimensions are strictly performed.

A size measuring device (or method) for measuring the size of the electron gun 3 is disclosed. FIG. 8 shows an example of such a conventional dimension measuring device.
This is disclosed in Japanese Patent No. 043.

That is, in this device, the electron gun 3 is detachably fixed, and the grid 1 to be measured is located at the rotation center (position of the pin 10a) of the measuring body 10 which is formed so as to be rotatable around the pin 10a as a fulcrum.
After fixing the electron gun 3 so that the gap of 1 is located, the measuring body 10 is driven to rotate right and left by the motor 12 via the friction roller 11 which is in contact with the outer end surface 10b formed concentrically with the pin 10a. To do.

Measurement light reciprocally scanned with a predetermined width from a laser oscillation device 14 is incident on the center of rotation from the side through a vibrating mirror 13, and the passing light is received by a sensor 15.

When the direction of the scanning laser light and the rotating grids 1 and 1 become parallel, the maximum light receiving time value is detected from a plurality of signals sent within a fixed time and sent to the display device 17. The value is converted into the interval W and displayed.

After the measurement of the gaps of the grids 1 and 1 is completed, the electron gun 3 is moved with respect to the measuring body 10 so that the next gap is located substantially at the center of rotation through which the measurement light passes, and the same as above. The measurement will be performed.

<Problems to be Solved by the Present Invention> However, in the above-described conventional measuring device or measuring method, the object to be measured is rotated with respect to the fixed measuring light, and therefore, the number of times is increased. On the moving side (measurement body 10, friction roller 11, motor 12 in the above example), a holding mechanism for holding the object to be measured, a rotating mechanism for rotating the object to be measured, and a rotating mechanism on the rotating mechanism. There is a problem that a moving mechanism for sequentially measuring a plurality of gaps to be measured of an object to be measured is sequentially aligned with the center of rotation, and instability increases due to stacking of structures.

Further, since optical scanning is performed using the vibrating mirror, the scanning speed of light varies sinusoidally with position. Therefore, according to the above method of measuring the light passage or cut-off time, the measured value greatly changes depending on whether the object to be measured is placed at the center of the scanning range or at a position deviated from the center.

A rotating mirror can be used instead of the vibrating mirror as a scanning means, and in that case, it seems that accurate measurement can be performed even with time measurement, but it is said that the extreme value of the measured value is obtained while rotating the measured object. In dynamic measurement, high-speed mirror scanning is known to significantly reduce the measurement time (Reference (1) JP-B-56-2286, (2) Kojima, Kondo:
Anritsu Technical, NO.40 (1980) p.66).

Furthermore, the gaps and thicknesses to be measured are small (thin)
Some are densely lined and some are wide, varying. Therefore, a signal obtained by one scan may obtain a bright / dark signal corresponding to a plurality of gaps or plate thickness dimensions, and a countermeasure for that case is necessary.

As described above, the conventional technique lacks scrutiny in terms of the structure of the measuring machine, has poor accuracy, and is very difficult in practice when the dimensions of the object to be measured vary.

<Means for Solving the Problems> In order to solve these problems, the dimension measuring apparatus of the present invention structurally separates the moving mechanism of the object to be measured and the rotation of the measuring beam to improve accuracy. For this purpose, we introduced a method that can measure the dimensions correctly, and improved various measurement patterns to mask unnecessary signals in electrical processing.

Further, in the second invention, a tilt detecting section is provided which is rotatable about the axis so that the tilt of the plate with respect to the axis of the object to be measured can be measured and which gives the maximum (minimum) measured value of the object to be rotated. ing.

<Operation> Therefore, between the light emitting portion and the light receiving portion fixed to the mounting portion,
The object to be measured or the mounting portion is moved by the second drive unit so that the gap between the plate portions to be measured or the plate portion is located, and the mounting portion is rotated by the first drive unit. The gap between the plate portions of the object to be measured or the thickness of the plate portion is calculated by the calculation unit based on the received light signal from the light receiving unit when moved.

Further, in the second aspect, the inclination detecting section detects the inclination of the plate portion with respect to the axis of the object to be measured based on the received light signal.

<One Embodiment of the Present Invention> (FIGS. 1 to 3) Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a dimension measuring device 20 according to an embodiment of the present invention, and FIG. 2 is a plan view of the embodiment.

In the figure, 21 is a stepped base,
A first drive unit 22 including a stepping motor or the like is formed on the upper surface 21a of the one end side formed low.

The first drive unit 22 finely rotates the upwardly projecting rotary shaft 22a within a predetermined angle range (for example, 1 / 10,000 degree for one pulse input) by a pulse signal from the outside. Rotate in steps.

A rectangular flat plate-shaped mounting portion 23 is attached to the upper end of the rotating shaft 22a.

On the upper surface portion 23a of the mounting portion 23, a light emitting and receiving device 24 formed in a U shape is mounted and fixed.

A light emitting unit 25 for emitting laser light scanned by a vibrating mirror (not shown) from a slit-shaped emission window 24a to a light receiving window 24b on the other end opposite to the light emitting / receiving apparatus 24 is housed at one end of the light emitting / receiving device 24. There is.

Further, inside the light receiving window 24b side, there is provided a light receiving unit 26 which receives incident light and outputs this light receiving signal.

In the light emitting and receiving device 24, the scanning light beam emitted from the light emitting unit 25 to the light receiving unit 26 is the center of rotation of the mounting unit 23 (rotation axis).
It is mounted and fixed on the mounting portion 24 so as to be orthogonal to the extension line of 22a).

A groove 27 is formed on the upper surface 21b of the base 21 on the other end side, which is formed high, in the direction of the rotation axis 22a of the first drive portion 22, and above the groove 27, the groove 27 is formed. A movable body 28 that is guided and slidably formed is arranged.

The movable body 28 is formed in a substantially rectangular parallelepiped shape, and inside thereof,
The motor 29 is attached.

The rotating shaft 29a of the motor 29 projects from the side of the movable body 28 in the direction of the light emitting and receiving device 24, and the end of the object to be measured such as an electron gun is attached to the chuck mechanism at the tip of the rotating shaft 29a. A holding device 30 for holding by (not shown) is attached.

A second drive unit 31 that slides the movable body 28 along the groove 27 is arranged on the front surface side of the movable body 28.

The second drive unit 31 is composed of a stepping motor (not shown) and the like, and is driven by a pulse signal from the outside.
The movable body 28 is slid finely.

The motor 29 in the movable body 28 rotates the rotating shaft 29a every 180 degrees by a pulse signal from the outside, and the holding device 30 rotates the axis of the object to be measured and the rotating shaft 29a. The object to be measured is held at a position where the center does not match.

Next, the control unit of the above dimension measurement 20 will be described.

FIG. 3 is a control unit for controlling the drive of the first and second drive units 22 and 31, the motor 29, etc. of the dimension measuring device 20 and displaying the measured value based on the light receiving signal from the light receiving unit 26. FIG. 35 is a schematic block diagram of 35.

In the figure, 36 is the first and second drive units 22 and the movable body.
28 is a drive control unit that detects a pulse signal for each of the motors 29.

The reference numeral 37 calculates the dimension value for each scanning using the light reception signal from the light receiving section 26 while the placing section 23 is rotated once within the predetermined angle range by the first driving section 22, and the maximum dimension value is calculated. This is a calculation unit that calculates.

Reference numeral 38 counts the pulse signals sent from the drive control unit 36 to the first drive unit 22, converts the count value when the maximum detection signal from the calculation unit 37 is received into an angle value, and outputs it. It is a tilt detector.

Reference numeral 39 denotes a display unit that displays the dimension value from the calculation unit 37 and the angle value from the tilt detection unit 38.

<Operation of the Embodiment> Next, the operation of the embodiment will be described.

First, as shown in FIG. 2, the electron gun 3 of the DUT is
It is fixed to the holding device 30.

Next, the movable body 28 is moved toward the light emitting and receiving device 24 by the pulse signal of the drive control unit 36, and as shown in FIG.
.. is stopped when the center of the first gap A between the grids 1, 1, ... Of the electron gun 3 reaches the position on the rotary shaft 22a (this operation is performed in advance by knowing the design dimensions of the object to be measured). It is also possible to make a mobile program).

Next, a pulse signal is detected from the drive control unit 36 to the first drive unit 22, and the light emitting and receiving device 24 reciprocates in a predetermined angle range θ stepwise at a step around the rotation shaft 22a. Be moved.

The scanning light beam from the light emitting section 25 scans the H side of the first gap A between the grids 1 and 1 as shown in FIG.
Reach 26

At this time, the received light signal from the light receiving unit 26 is a- in FIG. 6 (a).
It becomes like 1.

In the calculation unit 37, this signal is differentiated as shown by a-2, and the boundary between light and dark is obtained. Next, of the differential pulses, as shown by a-3, the first rising pulse and the last falling pulse are extracted, and a signal for the gap is obtained.

Further, as shown in b-1 and b-2 of FIG. 6 (b), when a large number of boundary signals appear in one scanning signal,
The gap to be measured is positioned near the center of the scanning light beam, a differential signal is extracted (b-4) by the mask signal (b-3) based on the size of the object to be measured, and a signal (b-5) corresponding to the gap is obtained. ) Is obtained.

Since the design dimensions of the object to be measured can be known in advance, positioning the gap to be measured near the center of the scanning beam and programming the width of the mask signal to be slightly wider than the gap will allow measurement of objects of various shapes. You can

In this way, the maximum value of the clearance signals obtained during the rotation of the light emitting and receiving device 24 is the clearance dimension to be obtained, and the maximum dimension value and the angle value of the light emitting and receiving apparatus 24 that gives this maximum dimension value are It is output to the display unit 39 and displayed.

Next, when a pulse signal is input from the drive control unit 36 to the motor 29 of the movable body 28, the electron gun 3 is inverted by 180 degrees, so that the parallel light beam from the light emitting unit 25 is shown in FIG. 5 (b). As it passes through the L side of the first gap A between the grids 1, 1
Will reach 26.

As a result, the upper and lower gap dimensions of the first gap A between the grids 1 and 1 and the inclination with respect to the axis are measured, and the vertical variations of the gap A are also measured.

Next, when a pulse signal is given to the second drive unit 31, the movable body 28 is moved in the direction of the light emitting and receiving device 24 while the mounting unit 23 is rotating, and the movable body 28 is moved between the grids 1, 1 ,. When the center of the gap B of No. 2 reaches the position on the rotating shaft 22a, the same operation is repeated thereafter, and the gap between the grids 1, 1, ... The slope is measured sequentially.

<Other embodiment of the present invention> In the above embodiment, the scanning light beam from the light emitting portion is emitted into the gap between the grids 1, 1, ..., and the gap size and the inclination with respect to the axis are measured. The width of the scanning light beam is set to be wider than the plate thickness of the grid 1, and the second drive unit 31 is controlled so that the center of the grid 1 is located above the rotation shaft 22a, and the light emitting and receiving device is rotated. The plate thickness of the grid 1 may be calculated based on the light reception signals from the light receiving units 26 of 24.

In the above example, the dimensions of the electron gun were measured as the object to be measured, but the dimension measuring device of the present invention can measure other objects to be measured other than the electron gun in exactly the same manner. .

<Effects of the Present Invention> The dimension measuring device of the present invention has a simple structure because the holding mechanism for the object to be measured and the parallel light beam rotating mechanism are independently formed as described above. And the mechanical instability is reduced. Also, the gap between the plate parts and the plate thickness,
It is possible to continuously measure the inclination between the plate and the axis and the like, which has the effect of significantly improving the measurement efficiency and accuracy.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a plan view of the embodiment, and FIG. 3 is a schematic block diagram showing a control unit of the embodiment. FIG. 4 is a schematic plan view showing the operation of the embodiment, and FIGS. 5 (a) and 5 (b) are schematic perspective views showing the operation of the embodiment. 6 (a) and 6 (b) are explanatory views of a light reception signal obtained by the light receiving unit, FIG.
FIG. 8 is a schematic perspective view showing an electron gun, and FIG. 8 is a schematic view showing a conventional device. 20: Dimension measuring device, 21: Base, 22: First drive unit, 22a: Rotating shaft, 23: Mounting unit, 25: Light emitting unit, 26
…… Light receiving part, 28 …… Movable body, 30 …… Holding device, 31 …… Second drive part.

Claims (2)

[Claims] 1. A size measuring device for measuring the size of an object to be measured, which has at least two or more plate parts formed facing each other with a gap so as to be orthogonal to one axis. A light emitting unit that is fixed to the mounting portion and that emits a scanning light beam that is wider than the thickness of the gap or the plate portion in the gap between the plate portions of the object to be measured or the plate portion; The light receiving portion that receives the scanning light beam from the light emitting portion that has passed through the object to be measured, and the emitting direction of the scanning light beam emitted from the light emitting portion by rotationally driving the mounting portion and the object to be measured. A first driving unit for displacing an angle formed by the axis within a predetermined range; and a light emitting unit in which a gap between the plate units to be measured of the object to be measured or the plate unit is fixed to the mounting unit. Place the DUT or the mounting part so that it is located between the light receiving part. A second drive unit that moves along the axis of the object to be measured, and the light receiving signal from the light receiving unit when the mounting unit is rotationally driven by the first drive unit, based on the light receiving signal from the light receiving unit. A dimension measuring apparatus comprising: a calculation unit that calculates a gap between plate portions of a measurement object or a thickness of the plate portions. 2. A dimension measuring device for measuring the dimension of an object to be measured, which has at least two or more plate portions formed to face each other with a gap so as to be orthogonal to one axis. A light emitting unit that is fixed to the mounting portion and that emits a scanning light beam that is wider than the thickness of the gap or the plate portion in the gap between the plate portions of the object to be measured or the plate portion; The light receiving portion that receives the scanning light beam from the light emitting portion that has passed through the object to be measured, and the emitting direction of the scanning light beam emitted from the light emitting portion by rotationally driving the mounting portion and the object to be measured. A first driving unit for displacing an angle formed by the axis within a predetermined range; and a light emitting unit in which a gap between the plate units to be measured of the object to be measured or the plate unit is fixed to the mounting unit. Place the DUT or the mounting part so that it is located between the light receiving part. The rotation angle of the second drive unit that moves along the axis of the object to be measured and the mounting unit that is rotated by the first drive unit is detected, and the detection signal and the light receiving unit from the light receiving unit are detected. A dimension measuring device comprising: a tilt detecting section that detects a tilt of the plate section with respect to the axis of the object to be measured based on a light reception signal.