JPS58113803A - Device for measuring displacement of body to be measured - Google Patents

Abstract

PURPOSE:To measure the displarement of the body to be measured without contact regardless of the effect of circumferential electromagnetic fields, by irradiating a radiating beam to the reflecting surface of the body to be measured, and receiving the reflected radiating beams by a plurality of radiating beam receiving means. CONSTITUTION:A light emitting element is connected to the other end of a light transmitting fiber 1. Light irradiates on the reflecting surface 3 of the body to be measured 2 from a light emitting surface 4 of the fiber 1. The reflected light is received by a plurality of light receiving fibers 5. The amount of light received by the light receiving fiber 5 varies with the displacement of the reflecting surface 3. The displacement of the reflecting surface 3, i.e. the displacement of the body to be measured 2, is obtained from the correlation of the ouput values of the light receiving elements which are connected to the other ends of the light receiving fibers. A plurality of light receiving fibers 7, 8, 9, and 10 are arranged around the light transmitting fiber 1. Thus the displacements of the body to be measured in the directions x, y; and Z can be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a displacement measuring device for a measured object that can obtain the displacement of the measured object from the amount of reflected radiation beam therefrom.

(2) Background of the technology Since the means of propagating signal components in acceleration sensors and the like is electrical signals, the acceleration sensor is placed in an environment with a strong electromagnetic field to measure the acceleration of the object being measured. In some cases, the effect of the electromagnetic field becomes so strong that satisfactory measurements cannot be made, which is a disadvantage, and a solution to this problem is desired.

(3) Conventional technology and problems Conventional acceleration sensors use piezoelectric elements or semiconductor gauges, and the signal that conveys the acceleration component is electrical, so it is difficult to place the sensor in a strong electromagnetic field. In state measurement, the acceleration component signal is affected by a strong electromagnetic field, causing distortion in it. Therefore, the measurement results inevitably include errors, making accurate measurement difficult or impossible.

These matters naturally also apply to the measurement of displacement and velocity of an object to be measured.

(4) Purpose of the Invention The present invention was devised by paying attention to the problems contained in the prior art as described above, and its purpose is completely different from that of the conventional method which uses a radiation beam as a displacement component transmission means. An object of the present invention is to provide a novel displacement measuring device for a measured object.

(5) Structure of the Invention The purpose of this invention is to irradiate the radiation beam radiated from the beam sending means toward a reflecting surface having a curved surface such as a spherical surface provided on the object to be measured, and to generate a plurality of reflected radiation beams from the curved surface. Beam reception is accomplished by receiving means and displaying displacement in response to these displacement components.

(6) Embodiments of the Invention The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the invention. Reference numeral 1 denotes a radiation beam sending means, which is, for example, a light sending fiber (this will be explained below). The light receiving end of the fiber 1 is coupled to a light emitting element (not shown). Reference numeral 2 denotes an object to be measured, for example, a spherical body supported by a spring or the like, and the surface 3 to which the light from the fiber 1 is irradiated forms a monotonically convex curved surface toward the light transmitting surface 4 of the fiber 1. The radiation beam receiving means 5 acts as a reflecting surface to reflect the light to the means 5. This reflective surface is, for example, a spherical surface. The radiation beam receiving means 5 is, for example, a light receiving fiber (this will be explained below). The amount of light received by these light-receiving fibers changes according to the displacement of the reflecting surface 3, and the voltage value generated at the output of a light-receiving element (not shown) coupled to the light-transmitting surface of the fiber 5 also changes accordingly. The output system from each light receiving element is configured to display the displacement of the reflecting surface 3, that is, the displacement of the object to be measured, from the correlation between the output voltage values of each of these light receiving elements.

Next, the operation of the apparatus of the present invention configured as described above will be explained.

As shown in FIG. 1, if the object to be measured 2 is a sphere and its reflective surface is a spherical surface, and it is displaced from the position shown by the dotted line to the position shown by the solid line, then the fiber 1 at the position shown by the dotted line The displacement from the light transmitting surface 4 of the fiber 5 and the light receiving surface 6 of the fiber 5 in the direction perpendicular to those surfaces, that is, the Z-axis direction is the second
As shown in the figure, when the output voltage of the light-receiving element is zP and the output voltage of the light-receiving element is Vp, the displacement from the light-transmitting surface 4 and the light-receiving surface 6 is zQ when it is displaced to the position indicated by the solid line. The element output voltage becomes VQ.

The difference in displacement (ZQZP), that is, the displacement of the sphere, is the output voltage vP
, vQ and the relationship shown in FIG.

In such measurements, the light transmits the displacement component, so even if there is a strong electromagnetic field in its path, it will not be affected by it, and a measurement system with a high 87'N ratio can be used. In addition, they are lightweight and small in size.

Figure 3 shows a sphere 2 in a direction parallel to the light transmitting surface 4 of the light transmitting fiber 1 and the light receiving surface 6 of the light receiving fiber 5, that is, in the X-axis direction.
Fig. 4 shows a state diagram in the case of displacement, and when such a displacement occurs, the output voltage generated from the light receiving element coupled to the light receiving fiber 5 becomes as shown by curves 11 and 12 in Fig. 4.

By determining the difference between these output types and pressures, it is possible to determine how much displacement is occurring in the sphere 2 and its direction.

In this case as well, the same effect as in FIG. 1 can be obtained.

Figures 5 and 6 show a configuration in which a sphere is three-dimensionally supported by a spring or the like, and the light transmitting fiber 1 and the light receiving fibers 7.8, 9.10 are arranged with respect to the sphere, and the three-dimensional displacement is The specific configuration is shown in FIG. 7. In FIG. 7, if the X axis is as shown, the Y axis is perpendicular to the plane of the paper, and the z axis is as shown. In these axial directions, the sphere 2 is supported by springs as described above, and of these springs, only the spring 11 in the X-axis direction is shown. Reference numeral 12 denotes a sensor head containing the above-mentioned spring and sphere, and a light transmitting fiber 1 and a light receiving fiber 7.9 are disposed between this head and the light emitting element 13 and light receiving element 14.15. To simplify the drawing, the receiving fiber 8.10
And the light receiving element therefor is omitted.

In this configuration, when the mass of the sphere 2 is M, and the spring constant of each spring is 2, Ky, respectively, the force displacement is applied to each acceleration component i, y, 'i, and as shown in Fig. 5. 7.8.9.1 Each fiber in the fiber configuration as shown
0, and the output voltage from each of the light receiving elements corresponding to this is v7. v8. v3. v engineering. Below, father = v7 v, , y = ■, -v,. , 'i, =
V7+Vg +V, 10V engineering. Each acceleration component is obtained as follows. Further, each acceleration component in the case of the fiber configuration shown in FIG. 6 is as follows. x=V7+
Vlo CVB +Vg), Qi V, +V8- (
V, +V1o), °1=v7+v8+v, 1o.

The acceleration of the sphere 2 can be measured from these values.

In this measurement, the same type as in Fig. 1 was used.

There is no effect of the fundamental field, therefore the /N ratio is high, and the device can be made lightweight and compact.

Furthermore, since the gravitational acceleration components in each direction can be measured in the same way, acceleration calibration can be easily carried out.

In the above description of FIG. 7, if the springs in the y direction and two directions are removed, and the fibers 8 and 10 or the fibers 7 and 9 in FIG. 5 are removed, the device configuration is the same as that in FIG. 1.

In the above embodiment, an example in which the reflecting surface is a spherical surface has been described, but it may be formed into an ellipsoidal surface or the like. Sorry, the means for transmitting the displacement component may be other than light, such as infrared rays.

(7) Effects of the Invention As is clear from the above explanation, according to the present invention, the difference between the radiation beams reflected by the reflecting surface, such as a spherical surface, of the measured object that is displaced relative to the measurement system The displacement of can be measured separately therefrom. Therefore, unlike conventional piezoelectric elements, there is no need to directly contact the detection section with the object to be measured. In addition, when using light as a radiation beam, it is not affected by strong electromagnetic fields even in environments where there is a strong electromagnetic field, and it is possible to measure with a high SZN ratio, which improves measurement accuracy and reliability. will improve. It also helps to reduce the size and weight of the device, so it can be used in a wider range of environments.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a reflection surface displacement-output voltage characteristic curve diagram when the reflection surface is displaced in the optical axis direction, and FIG. 3 is a diagram showing the reflection surface in the apparatus shown in FIG. A diagram showing the case of displacement perpendicular to the optical axis, Figure 4 is a reflection surface displacement vs. output voltage characteristic curve diagram in Figure 3, and Figures 5 and 6 are light transmission when measuring three-dimensional displacement. FIG. 7 is a diagram showing a more specific configuration of the apparatus shown in FIG. 1, FIG. 5, or FIG. 6. In the figure, 1 is a radiation beam sending means, 2 is an object to be measured, 3 is a reflecting surface, and 5.7, 8, 9.10 are radiation beam receiving means. Patent applicant Fujitsu Ltd. Figure 1 Figure 7 Figure 2 Figure 3 Figure 4 Figure 20

Claims (1)

[Claims] 1) A radiation beam sending means for irradiating a radiation beam, a measuring object reflecting surface forming a monotonically convex or concave curved surface toward the radiation beam sending means, and a plurality of radiation beams that receive the radiation beam reflected by the reflecting surface. The radiation beam receiver comprises means, and the radiation beam receiver is configured to display the displacement of the object to be measured in response to an output signal of the means. A displacement measuring device for a measured object according to claim 1, characterized in that the measured object described in claim 1 is characterized by: