JPH0288913A - Angle measuring instrument - Google Patents

Abstract

PURPOSE:To measure an angle in a non-contact state even of an object having the complicated shape, so far as the measuring surface can be looked from the outside, by reading out the rotation angle of a turntable in the manner of gradually detecting the position, on which a laser beam is exactly reflected, while turning the turntable along with putting the laser beam to the measuring surface. CONSTITUTION:The light coming from a laser light source 1 is reflected on the measuring surface of an object 6 to be measured which is placed on the turntable 3 and received by a photodetector 5. But the reflected light is not always returned to the photodetector 5, so the light reflected on the measuring surface is detected by the photodetector 5 while turning the turntable 3 along with putting the light from the laser light source 1 to the measuring surface of the object 6 to be measured on the turntable 3. Then the measurements for relative angles between two points or more desired to measure are made by means of reading out the rotation angle of the turntable 3 at the peak value with a rotation angle detector 7. The angles are thereby measured easily and accurately in noncontact state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the field of measurement technology in which relative angles between two points or two or more surfaces of an object to be measured are measured in a non-contact manner.

[Conventional technology]

Conventional techniques for measuring angles in the measurement field include directly measuring angles with autocollimators, levels, projectors, etc., and determining angles from dimensional measurements using tool microscopes, coordinate measuring machines, etc. . However, there is a drawback that conventional measurement methods cannot measure objects that have complex shapes, or cases where the measurement location cannot be touched to prevent contamination, such as mirrors.

[Problem to be solved by the invention]

In view of the above points, the present invention provides a device that can measure angles of any complex shape without contact as long as the measurement surface is visible from the outside.

[Means for Solving the Problems] The elements of the present invention are to use a rotary table on which an object to be measured is placed and a laser light source, and to irradiate the measurement surface with laser light and while rotating the rotary table, reflect the laser light specularly. This is an angle measuring device that reads the rotation angle of the rotary table while sequentially detecting the positions of the rotary table.

The present invention will be described below based on illustrative embodiments.

The configuration of the non-contact angle measuring device according to the present invention is shown in FIG. 1. As shown in FIG. (3) and the l-axis moving table (4) are placed at arbitrary distances apart.

A photodetector (5) is installed on the side of the laser light source (1), and outputs a signal when it receives reflected light. A rotation angle detector (6) such as a rotary encoder is installed on the rotary table.

At this time, the light from the laser light source (1) is transferred to the rotary table (3).
) on the measuring surface of the object to be measured (6), and while rotating the rotary table (3), the photodetector (5) detects the light reflected on the measuring surface. )
The relative angle between two or more points to be measured is measured by reading the rotation angle with a rotation angle detector (6).

[For production]

The principle of angle measurement according to the present invention will be explained below with reference to FIG. The light from the laser light source (1) is reflected by the measurement surface of the object to be measured (6) placed on the rotary table (3) and is received by the photodetector (5). As the object to be measured (6) is placed at an arbitrary position on the rotary table (3), the reflected light does not necessarily return to the photodetector (5). Rotate it so that the reflected light is received by the photodetector (5). At this time, the position of the rotary table (3) is read by the rotation angle detector (6) and is θ. (Figure 2(b) shows this state).

Next, the rotary table (3) is rotated to a position where the angle is desired to be determined, and the rotary table (3) is rotated to a position where the laser beam is incident on the photodetector (5). The position of the rotary table (3) at this time is read by the angle detector (5) and is set as θ (FIG. 2(C) shows this state). Therefore, the relative angle between the two points you want to measure is θ
=1θ. It can be determined by -θ and l. In this case, the explanation is between two points, but the angle between two or more points can be determined by continuously rotating the rotary table (3) and reading the rotation angle at this point while detecting the reflected light of the laser beam. Continuous measurement is also possible.

Furthermore, in cases such as those shown in FIGS. 2(b) and 2(C), there is a possibility that the laser beam may deviate from the reflecting surface when the range of the measurement surface is narrow. For this reason, it is also possible to perform measurements while controlling either of the movable tables (2) or (4) so that light detection is performed while scanning a certain distance in a direction perpendicular to the optical axis.

〔Effect of the invention〕

As described above, the angle measuring device of the present invention has the following effects.

1) Measurement can be performed without contact.

2) Angles can be easily and accurately measured.

3) Even complex shapes can be easily measured.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an angle measuring instrument according to the present invention, and FIG. 2 is a detailed explanatory diagram of the present invention. (1) - Laser light source, (2) - 2-axis moving table, (3) 1-rotation table, (4) - Sub-axis moving table, (5) - Photodetector, (6) -... Rotation angle detector. Figure 112 (a) (b) (C)

Claims (2)

[Claims] (1) Using a rotary table on which the object to be measured is placed and a laser light source, the laser beam is applied to the measurement surface and the rotary table is rotated, and the rotation angle of the rotary table is read while sequentially detecting the positions where the laser beam is specularly reflected. Angle measuring device that is a configuration. (2) The first step is to perform measurements while scanning a rotating table or laser light source for a certain distance in a direction perpendicular to the optical axis.
Angle measuring device as described in section.