JPS61265574A - Apparatus for detecting displacement of weight - Google Patents

Abstract

PURPOSE:To detect the absolute value and direction of acceleration with high accuracy, by providing a wt. to the free end of an optical fiber fixed at one end part thereof and forming a free end at the other end part thereof and receiving light passing through the optical fiber at the free end side by a charge coupling element. CONSTITUTION:One end part of an optical fiber 11 is fixed to the part of a fiber piercing hole 10a and a wt. 12 is mounted to the free end of the other end part of said fiber. Because the optical fiber 11 is always vertically suspended, the light emitted from a light source 13 passes through the optical fiber 11 to be formed into an image on the central part of a charge coupling element 14. However, if acceleration is acted in any direction within a horizontal plane, the wt. 12 is displaced and the optical fiber 11 is also curved to change a position where the light emitted from the optical fiber is incident to the element 14. Therefore, the difference between the central position of the element on which light is incident from the lower end of the optical fiber 11 before acceleration is acted and the position where the light from the optical fiber 11 is incident when acceleration is acted is operated by a control circuit 15 and the absolute value of the magnitude of acceleration and the direction signal of acceleration are outputted from an output circuit 23.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a method for controlling a damper of a suspension of an automobile, for example, by using a weight to measure acceleration acting on a moving automobile in order to obtain a comfortable ride. G sensor that detects
The present invention relates to a weight displacement detection device applied to other oblique angle sensors and the like.

[Conventional technology]

FIG. 3 is a diagram showing a conventional G sensor using a weight, as shown in, for example, Japanese Utility Model Application Publication No. 58-165670. In the figure, (1) ij casing, (2) a weight ( 3) A support plate that supports and constitutes a fulcrum.

(4) is a slider that moves up and down by the swing of the weight (3).

(5) is a photo interrupter containing a light emitting part (6) and a light receiving part (7), and the optical axis between the light emitting part (6) and the light receiving part (7) is interrupted by vertical movement of the slider (4). .

The conventional G-sensor using a weight is configured as described above, and consists of a push-up plate (3a) attached to a weight (3) starting from a fulcrum (8) on which an acceleration of a certain level or more acts. is tilted, the slider (4) is pushed up, and the optical axis of the photointerrupter (5) is cut off, so that the light receiving unit (6) can detect the fact that the acceleration exceeds a certain value as a change in the electrical signal. It has become.

[Problem that the invention seeks to solve]

In the conventional C sensor using a weight as mentioned above, the movement of the weight is converted into vertical movement, so it is difficult to obtain stable reproducibility because it is affected by the friction of the sliding part. , due to wear of moving parts during use.

Its characteristics gradually change. Also, because the natural frequency determined by the length of the weight from the fulcrum cannot be increased, it only responds to acceleration at low frequencies. Furthermore, there is a first problem in that the direction and absolute value of acceleration cannot be obtained.

This invention was made to solve the above-mentioned problems, and it is possible to realize C sensors and other tilt sensors, etc., which have good reproducibility and whose characteristics do not change much even after long-term use. C sensor with natural frequency,
The object of the present invention is to obtain a weight displacement detection device that can realize a C sensor that can detect the direction and absolute value of acceleration, a tilt sensor that can detect the direction and angle of tilt, etc.

[Means for solving problems]

The weight displacement detection device according to the present invention is an optical fiber having one end fixed and the other end free.

A weight provided at the free end of this optical fiber.

The device includes a light source that supplies light to the optical fiber from the one end thereof, and a charge-coupled device that receives light from the light source that has passed through the optical fiber at the free end side.

[Effect]

In this invention, the optical fiber is fixed to a fixed part, and the movement of the optical fiber due to displacement of the weight due to acceleration or other tilting can be directly detected, and friction and wear due to the presence of sliding parts can be detected. Not affected. In addition, since the support structure is fixed at one end, its natural frequency is the third
Structure C in which the slide moves up and down in response to the weight shown in the figure
It is considerably larger than a sensor and can stably detect acceleration over a wide range of frequencies. Also.

Since the configuration is such that the light from the light source that has passed through the optical fiber is received by the charge-coupled device, the direction of acceleration, inclination, etc. and the absolute value of the magnitude thereof can be detected.

[Embodiments of the invention]

FIGS. 1 and 2 are longitudinal sectional views showing an example of a C sensor as an embodiment of the present invention, and (9a) shows a hollow and airtight upper container for blocking external light.

The lower part (9b) is a hollow and airtight main container for blocking external light, and is fixed to, for example, the body of an automobile (not shown), and is a so-called fixed part. α0 is a plate that fixes the upper end, that is, one end, of a predetermined length of vertically hanging optical fiber αυ through the fiber through hole (10a), and suspends the reference optical fiber 0υ in the fixed lower container (9b). The upper container (9b) is placed outside the upper part of the plate α1 and the lower container (9b).
9a) is attached. A weight α2 is attached to the lower end of the optical fiber αυ to dampen the movement of these optical fibers when swinging and to adjust the natural frequency. A light emitting element such as a light emitting diode, that is, a light source (13) is provided, and the light emitted from this light source (+3) is passed through an optical fiber αυ to a well-known charge-coupled device (hereinafter abbreviated as CCD) at the inner bottom of the lower container (9b). The CCD α41 extends horizontally in the form of a disk in a horizontal plane, and when the acceleration of the weight a'avc is not acting, the lower end of the optical fiber αυ It is arranged at a position facing the planar center of the CCD (141 (the center when viewed from top to bottom in Figure 1). +15 is a control circuit that calculates the direction and magnitude of acceleration; oe\ 'i positive power terminal, αη is lead wire, θυ is resistor, α9 is anode terminal of light emitting diode (light source) α, (a) is negative power terminal, Qυ is lead wire (24 is light emitting diode (light source) ) (+3 cando terminal, c!31u This is an output circuit that outputs a signal corresponding to the absolute value of the direction and magnitude of acceleration in response to the output of S to the control circuit. Connected to the positive power supply terminal αe The lead wire αη is connected to the anode terminal α of the light emitting diode (light source) (13) through the resistor α barrel.The lead wire C2D is also connected to the negative power terminal Qυ.
n, is connected to the cando terminal of the light emitting diode (light source) α3.

Next, the operation of the above embodiment will be explained.

In the above-mentioned C sensor, the optical fiber αυ normally hangs down vertically as shown in FIG.

The light emitted from the light source 0 passes through the optical fiber aυ and forms an image at the center of C0D (141) as shown by the arrow.

When acceleration acts on the weight a3 in any direction within the horizontal plane, the zero weight a side is displaced as shown in FIG. 2, and the optical fiber αυ is also bent in accordance with the displacement of the weight α2,
The position where the light emitted from the lower end of the optical fiber αυ hits the CCD (141) changes. The control circuit (I9) calculates the difference between the position where the light from the optical fiber αυ hits the CCDQ4) when the light is applied, and the control circuit (19) obtains the absolute value and direction of the magnitude of acceleration as acceleration information. , an absolute value signal of the magnitude of acceleration and a direction signal of acceleration are output from the output circuit (2).

The embodiment shown in FIG. 1 and FIG. 9aX9b) itself is tilted to the left, for example, the relative positional relationship between the lower container (9b) and the optical fiber αυ1 weight az will be the same as in FIG. 2, and therefore the tilt direction and tilt angle.

It is also possible to detect an inclination degree of 1 grade. Furthermore, even if the entire embodiment shown in FIG. 1 is arranged upside down, the same effect as in the embodiment described above can be obtained.

Yet again. In the embodiment described in Ar1, a weight α2 separate from the optical fiber αυ was attached to the optical fiber αυ. It has a similar effect.

In any case, the conventional device shown in Fig.
J' play) (3a), slider (4) is unnecessary.

Furthermore, as shown in Figure 3, there is no need to mechanically permit the rocking of the weight (3) on the support plate (2) or to create a structure that allows the slider (4) to move up and down, thereby preventing malfunctions caused by friction. There is no reduction in reliability due to wear and tear.

〔Effect of the invention〕

As explained above, the present invention includes an optical fiber whose one end is fixed and the other end is free, a weight provided at the free end of the optical fiber, and a light beam from the one end to the original fiber. Since the configuration includes a light source that supplies light and a charge-coupled device that receives light from the light source that has passed through the optical fiber at the free end side, the displacement of a single weight can be achieved without being affected by friction or wear. 9 For example, acceleration and inclination.

This has the effect of being able to detect the absolute value and direction of etc. with high precision using an inexpensive device.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing an embodiment of the present invention in the case of a G sensor, Fig. 2 is a longitudinal side view showing the operating state of the G sensor of Fig. 1, and Fig. 3 is a conventional G sensor. FIG. In the figures, (9a) and (9b) are fixed containers, al is a fixed grating, αυ is an optical fiber, α is a weight, 0 is a light source, and α is a charge coupled device. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (3)

[Claims] (1) an optical fiber with one end fixed and the other end free; a weight provided at the free end of the optical fiber; a light source that supplies light to the optical fiber from the one end; and a weight displacement detection device including a charge coupled device that receives light from the light source passing through the optical fiber at the free end side. (2) The weight displacement detection device according to claim 1, wherein the weight is displaced in accordance with acceleration. (3) The weight displacement detection device according to claim 1, wherein the weight is displaced relative to the fixing portion according to the inclination of the fixing portion that fixes the optical fiber.