JPS63120204A - Optical dimension measuring device - Google Patents

Abstract

PURPOSE:To simply measure a dimension in a non-contact state, by a method wherein a part of the rotary locus of emitted beam is blocked from the emitted beam by the article to be measured arranged so as to cross the rotary locus of said beam when the dimension of the outer or inner diameter of the article to be measured is measured and the dimensional value of the article to be measured is operated on the basis of the beam blocking angle-of- rotation position range of the emitted beam. CONSTITUTION:An article 12 to be measured is arranged to the front surface part of a total reflection plate 7 in parallel thereto in order to allow the outer diameter thereof to cross the rotary locus of emitted laser beam L and a part of the laser beam L is blocked by the outer diameter of the article 12 to be measured. By this mechanism, the incidence of the beam to a beam receiving element 8 is interrupted during a time when the beam L traverses the outer diameter of the article to be measured and the level of the electric signal inputted to an operation part 9 is allowed to fall during this time. The operation part 9 preliminarily counts the number of the pulse signals from a pulse generator 10 and collates the same with the level-down interval of the signal inputted through the beam receiving element 8 to calculate the beam blocking angle-of-rotation position range generated by the article 12 to be measured. By this method, the outer diameter value of the article 12 to be measured is calculated and the output signal corresponding to said value is sent out from an output part 11.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical dimension measuring instrument suitable for non-contact measurement of dimensions such as the outer diameter and inner diameter of a workpiece. be.

[Conventional technology]

Conventionally, this type of optical dimension measuring instrument has generally used a straight parallel light beam produced by a highly accurate optical system.

[Problem that the invention seeks to solve]

However, with such conventional optical dimension measuring instruments, the parts of the optical system need to be processed with high precision.
This was a factor in increasing costs.

[Means for solving problems]

The present invention has been made in view of these problems, and is designed to rotate an emitted light beam with respect to a center point, and to rotate the emitted light beam with respect to the center point, and to detect the The dimension value of the object to be measured is calculated based on the shielding rotation angle position range of the emitted light beam.

[Effect]

Therefore, according to the present invention, a part of the rotational locus of the emitted light beam is blocked by the object to be measured which is arranged to intersect with the rotational locus of the emitted light beam. Calculation of the dimension values of the object to be measured is performed.

〔Example〕

Hereinafter, the optical dimension measuring instrument according to the present invention will be explained in detail. FIG. 1 is a configuration diagram showing an embodiment of this optical dimension measuring device. In the figure, 1 is a laser oscillator, and 2 is a half mirror 13 that transmits the laser beam emitted from the laser oscillator 1. A first total reflection mirror 4 is disposed at an inclination angle of 45'' with respect to the laser beam that is incident after passing through the half mirror 2, and totally reflects the incident laser beam at right angles. This is a second total reflection mirror that is arranged at an inclination angle of 45 degrees with respect to the laser beam that is incident through the mirror, and totally reflects the incident laser beam at right angles to form an output laser beam.

Total reflection mirror 3 and total reflection mirror 4 have a distance of 1 between their centers.
The total reflection mirror 3 and the total reflection mirror 4 arranged in this manner constitute an output laser beam rotator 5. The output laser beam rotator 5 receives rotational driving force from a motor 6 and rotates around a drive shaft 5a indicated by a dashed line in the figure.At this time, the total reflection mirror 3 and the total reflection mirror 4 are configured to rotate while always maintaining their relative positional relationship. In other words, the total reflection mirror 4 is rotated by the output laser beam l with the drive shaft 5a as the axis, and the rotation of the rotator 5.
As shown in FIG. 2, the emitted laser beam L emitted through the emitted laser beam has a radius l with the drive shaft 5a of the emitted laser beam rotator 5 as the center P1.

The structure is as follows:

In order to project the rotation locus of the emitted laser beam L, a total reflection plate 7 is disposed to face the emitted laser beam rotator 5 at a predetermined distance, and the output laser beam irradiated onto the total reflection plate 7 is The laser beam is totally reflected in the incident direction to become a reflected laser beam, and this reflected laser beam passes through a total reflection mirror 4 and a total reflection mirror 3 to a half mirror.
The light is guided and reflected by the mirror surface of 2, and is received by the light receiving element 8. The reflected laser beam received by the light-receiving element 8 is converted into an electrical signal according to the intensity of the light, and the electrical signal is input to the arithmetic unit 9. Further, pulse information from a pulse generator 10 that drives the motor 6 is also input to the calculation unit 9, and the calculation results in the calculation unit 9 are sent to the output unit 11.
It is now sent to .

Next, the operation of the optical dimension measuring instrument configured as described above will be explained. That is, when measuring the outer diameter of the object to be measured using this optical dimension measuring instrument, a desired coating is placed on the front surface of the total reflection plate 7 so that the outer diameter intersects the rotation locus of the emitted laser beam L. Place the object to be measured. For example, assume that a loft-shaped object to be measured (12 indicated by a broken line in FIG. 1) is placed in front of the total reflection plate 7, and the outer diameter of this object to be measured 12 is to be measured. In this case, the rotation locus of the output laser beam L projected onto the total reflection plate 7 is as shown in FIG.
A portion of the object to be measured 12 is blocked from light by its outer diameter. That is, while the emitted laser beam L crosses the outer diameter of the object to be measured 12, the incidence of the reflected laser beam on the light receiving element 8 is interrupted, and during this period, the level of the electrical signal input to the calculation section 9 is reduced. On the other hand, pulse information via the pulse generator 10 is inputted to the calculation unit 9 every moment, and the current rotation angle position of the emitted laser beam L in its rotation locus is recognized based on this pulse information. In other words,
The number of pulse signals input via the pulse generator 10 is counted in the calculation section 9, and the current rotational angular position of the emitted laser beam L is recognized from this count value. By comparing this recognized rotational angular position with the level down interval of the electrical signal input via the light receiving element 8, the shading rotational angular position range of the emitted laser beam L by the object to be measured 12 is determined. The outer diameter value of the object to be measured 12 can be calculated from the rotation angle position range, and an output signal corresponding to this outer diameter value is sent to the output section 11.

In this way, according to this embodiment, the outer diameter of the object to be measured 12 can be measured in a non-contact manner without using a highly precisely machined optical system, and the structure is simpler than the conventional one. This has the effect of reducing the total cost.

In this embodiment, both sides of the object to be measured 12 are arranged so as to intersect with the rotation locus of the emitted laser beam L, but even if only one side is arranged so as to intersect, its outer diameter can be measured. be able to.

In addition, in this example, the center axis S (Fig. 3) of the object to be measured 12 is arranged to intersect with the center 131 of the rotation locus of the emitted laser beam ■, as shown by the dotted line in Fig. 3, for example. Alternatively, the object to be measured 12 may be placed near the outer edge of the rotation locus of the emitted laser beam L. By adopting such an arrangement, the time period during which the emitted laser beam is blocked by the object to be measured 12 becomes longer, and the measurement resolution increases. Furthermore, the arrangement of the object to be measured 12 on the front surface of the total reflection plate 7 is not limited to parallel arrangement from the horizontal direction as shown in FIG. 3, but may be parallel arrangement from the vertical or diagonal direction. However, the outer diameter of the object to be measured 12 can be measured in the same manner.

Further, in this embodiment, the total reflection plate 7 is configured to reflect the emitted laser beam L, but instead of this total reflection plate 7, a light receiving face plate having a direct light receiving element may be used. Measured object 1 based on the size of the shadow that appears on the face plate.
It may be configured to measure the outer diameter of 2. Furthermore, instead of the total reflection mirror 3, a laser beam oscillator that rotates integrally with the total reflection mirror 4 may be directly arranged, or the total reflection mirror 4 itself may be configured with a laser beam oscillator, and this laser beam oscillator rotates around the drive shaft 5a,
A rotation locus may be created by the emitted laser beam. It should be noted that the object to be measured may have various shapes other than the round shape, and it goes without saying that the object to be measured is applicable to measurement of various dimensions such as not only the outer diameter but also the inner diameter.

〔Effect of the invention〕

As explained above, according to the optical dimension measuring instrument according to the present invention, the emitted light beam is rotated with respect to the center point, and the emitted light beam is rotated with respect to the center point. Since the dimensions of the object to be measured are calculated based on the shading rotation angle position range of the output beam, it is possible to measure the dimensions of the object without contact, without using a highly precise optical system. , the structure is simplified compared to the conventional one, and the cost per unit is reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the optical dimension measuring device according to the present invention, FIG. 2 is a diagram showing the rotation locus of the output laser beam emitted from this optical dimension measuring device, and FIG. FIG. 2 is a diagram showing the arrangement of objects to be measured that are arranged to intersect the rotation locus of an emitted laser beam. 1... Laser oscillator, 2... Half mirror 13, 4
... Total reflection mirror, 5 ... Output laser beam rotator, 5a ... Drive shaft, 6 ... Motor, 7 ... Total reflection plate, 8 ... Light receiving element, 9 ... Calculation Section 10... Pulse generator, 12... Measured object.

Claims (1)

[Claims] A light beam rotating means for rotating the emitted light beam with respect to a center point, and a shielding rotation angle position range of the emitted light beam by a measured object arranged so as to intersect the rotation locus of the emitted light beam rotated by the light beam rotation means. and a dimension value calculating means for calculating the dimension values of the object to be measured.