JPS5890173A - Detecting device for deflection of accelerometer - Google Patents

Abstract

PURPOSE:To facilitate zero-point adjustment by fitting a pickup holder to a base frame oppositely to a reflecting part provided on a plane perpendicular to the direction wherein a pendulum is movable, and by fitting a light-emitting element and two light-receiving elements at an angle of intersection equal to the axial line of the direction wherein the pendulum is movable. CONSTITUTION:A plate-shaped pendulum 1 for detecting acceleration is made of a material reflecting a light, and is supported by a base frame 4 at one end 3 thereof through the intermediary of a hinge 2. Moreover, a cylindrical torque coil 7 is fitted to the pendulum 1 in the direction perpendicular to the surface of the plate and driven. A differential reflection type deflection detector for detecting the deflection of the pendulum, which consists of light-receiving elements 10 and 10' and a light-emitting elements 11, is fitted to the end part positioned opposite to the hinge 2. The optical axis P-P' of the element 11 and the parallel optical axis R-R' of the elements 10 and 10' are set so that they are on the same plane and have an angle of intersection equal to the axial line of the dirction wherein the pendulum 1 is movable, and are fixed to a pickup holder 19 of the base frame 4. The holder 19 is provided with a pinhole 21, whereby the optical point of the element 11 is restricted in a prescribed manner on the reflecting surface 1a of the pendulum 1. Thus, the zero-point adjustment is facilitated and the precision in detection can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides acceleration of 1'! The present invention relates to a + deflection detection device, particularly a foul differential type deflection detection device for acceleration elbow.

Conventionally, many displacement detection devices for acceleration goods with small t (accuracy) have been used that detect displacement as a change in the electrostatic field. The device has the disadvantage that a lifter or the like for rescue is not necessary and the electric circuit is complicated.

On the other hand, conventional deviation detection devices using optical elements are either a transmission type in which a light-emitting element and a light-receiving element are arranged face-to-face; There is a reflective type, but both have one light emitting element.

Since it is configured with one light receiving element, this has the disadvantage that the zero point fluctuates due to changes in the amount of light emitted.

In addition, there is a deflection detecting device that eliminates the drawback of the zero point fluctuation by using two light receiving elements and detecting the differential output of the conventional transmissive deflection detecting device.
This also has the disadvantage that zero point adjustment is difficult.

Therefore, the main object of the present invention is to use one light-emitting element and two light-receiving elements, which are particularly compact, highly accurate, and have a simple structure, which allows easy zero point adjustment, and furthermore, allows for slight deviation. An object of the present invention is to provide an accelerometer deflection detection device capable of highly accurate detection.

The gist of the present invention is to include a joint, a base to which one end of the joint is fixed, a pendulum fixed to the other end of the joint, and a torquer that generates a torque from the base to the pendulum. In order to photoelectrically detect the relative deviation between the base of the accelerometer and the pendulum, there is provided a deflection detection device having a light emitting element and two light receiving elements attached to the base; a reflecting part provided on the surface of the pendulum perpendicular to the pendulum, a pickup holder mounted on the base opposite to the reflecting part, and a pickup holder having an angle intersecting the moving direction of the pendulum, At the same time as installing the
In the accelerometer deflection detecting device, the two light receiving elements are attached to the pickup holder at an intersection angle equal to the -1 - intersection angle in a plane including the optical axis of the light emitting element and the movable direction axis of the pendulum.

Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Figures 1 and 2 are a sectional view and a partially removed front view of a specific example of a 7JII speed needle using an example of the deviation detection device of the present invention. In the figure, (1) is a plate-shaped pendulum that detects acceleration, which is made of a material that reflects light efficiently or a material that has been treated with reflective treatment. A joint or hinge (2) consisting of a flexible portion formed by
At one end (+3) 17c, attach the base (4) to be described later.
) K is supported. This pendulum (1) has a hinge (2)
can be rotated only in the direction X-X, which is square to the plane of the paper in Figure M1, using the fulcrum (-). ) is attached to the pendulum (1) by a hinge holding plate (6).The pendulum (1) also has a cylindrical torque coil (7) extending perpendicular to the pendulum (1).
) is installed. A disk-shaped permanent magnet (8) and a cylindrical pole piece (9) are inserted into the torque coil (frame (4) without contacting the force).
) is attached by adhesive. This frame (4)
is made of electromagnetic soft iron, so the permanent magnet F811
From c, it forms an f[-1 magnetic circuit with the pole piece (9), serves as a yoke (return path), and together with the torquer coil (7), forms a torquer that drives the pendulum (1). . The frame (4) has two light receiving elements (1) which are the main part of the present invention and which detect the deflection of the pendulum (1).
A reflection differential type deflection detector consisting of 0),
2) is attached facing the opposite end.

The above-mentioned components already have the function of an accelerometer, and when they are fixed to the case α2 with a plurality of screws Q3 and integrated with the case, a characteristic name plate and cover α is formed. It is glued to the case 03 so that the inside of the case (12) can be kept airtight.

The external terminal (15) to which a lead wire (not shown) for supplying electric signals from IG, etc. and feedback current to the torquer coil (7) is connected to the light receiving element αω that constitutes the deflection detector. The terminal case (16) is hermetically bonded to the terminal case (IG), and the terminal case (16) is hermetically bonded to the case (12+) so that one end thereof is inside the case az.

In this way, the electrical system of the internal device is connected through the central opening (1η) of the terminal case Ufi), and
While filling the inside of the case with direct air or inert gas (e.g. helium gas), glue the lid (mark 1) to the opening side, keep the inside of the case (1, 21 airtight, and close the parts). 11- Prevents deterioration etc. and maintains stable performance over a long period of time.

In the accelerometer configured as described above, when acceleration is applied in the direction of the center 11 (11 Since the light reflected by the pendulum (1) and incident on the light receiving elements (101 and 06) of the deflection detector changes,
From these, an electrical signal corresponding to the deviation can be obtained. An electric signal proportional to the deviation of L6 is fed back to the L.L. coil (7), thereby restraining the pendulum (1) so that the electric signals of the light receiving elements α and (L6 become zero).

This electrical signal, or restraint current, is proportional to acceleration, so by measuring this current.

This allows you to know the input acceleration.

Next, using FIG. 3, which is a sectional view taken along line I-1 in FIG. 2, a detailed explanation of the reflective differential type deviation detection device of the present invention will be given.

In the present invention, one light-emitting element (Iυ and two light-receiving elements αα, a west are parallel to the center line of the former, that is, the optical axis P-P, and the respective optical axes of the latter, and the distance between them is center axis 1%-R
are fixed to the pickup holder (1!1) so that they are on the same plane and have an angle ψ.This pickup holder H is attached to the frame (1!1) shown in FIGS.
4) K is fixed. For this purpose, a mounting hole (A) for the light emitting element (1, 1) is provided in the pickup holder, and a pinhole (21J) is provided at the tip of the light emitting element (Iυ) to make the light into a beam. element (optical axis P from 11J
-P is restricted to form a minute elliptical light spot on the reflecting surface (1a) of the pendulum (1). or,
弼 is the mounting hole for the light receiving elements +10) and +101, which are provided in the pickup holder a9, and each element Q■ and 06
As described above, the optical axes of the two are spaced apart along the Y-Y direction parallel to and perpendicular to the optical axis.

In this case, the intersection angle ψ of the optical axis IL-⇠ and P-P is the optical axis p-p
is the angle of incidence ψ, (p
-1;

Of course, ψ1 is larger than 0 and smaller than 90°.

In FIG. 3, the reflecting surface (1a) of the pendulum (1) is aligned with the center line of the light emitting element αυ and the light receiving elements αa, ai]'-P
When the light flux (B) emitted from the light-emitting element aυ is reflected by the reflecting surface (1a) of the pendulum (1), the light flux (B) emitted from the light-emitting element aυ is reflected by the two light-receiving elements +101, (Iα). On the surface, as shown in Fig. 4, these two light receiving elements + It)
, to form a light spot such that at most each half of Ql is irradiated with an equal amount of light. At this time, the light receiving element 0α,
The differential output current of (11) is zero. However, the pendulum (1)
is related to the X-X direction that is harmonious with the reflecting surface (1a).1. ,X
If there is a slight deviation in the direction, the light receiving element 01. The light spot formed on the light receiving surface of α6 is perpendicular to the center line It-Y
For example, the light receiving element (IQIV
Since the amount of light hitting c is larger than the amount of light hitting the light receiving element α6, the differential output terminal derived from the light receiving elements 001 and +1.01 has a photocurrent corresponding to the deflection of the pendulum (1), even though it is not shown. occurs.

However, as mentioned above, the zero position of the pendulum (1) is not necessarily at the intersection of the center lines PP and RR of the light emitting element αD and the light receiving element αα, 06, and the zero position of the pendulum (1) (11゜α
Due to variations in the characteristics of a, an output current is generated even when no acceleration is applied to the pendulum (1), so adjusting the output current to zero is an important factor in the adjustment stage of the device.

In the present invention, the pickup holder al is slightly deviated in the X-X direction in FIG. It becomes possible to carry out zero position adjustment by moving in the Y-Y direction according to the zero position of 1).

That is, the first feature of the present invention is that an accelerometer for a shed can be manufactured by using a reflective displacement detection device.

The second feature of the present invention is that the conventionally used light emitting element,
The drawback of a reflective displacement detection device having one light-receiving element, that is, the zero point fluctuates due to temperature change, has been improved by using two light-receiving elements and detecting the differential output.

The third feature of the present invention is that the simple structure, configuration, and procedure of attaching the light emitting element and the light receiving element to the same pickup holder eliminate the zero position of the deflection detection device, which requires skill and time. The reason for this is that it has become possible to perform 14 adjustments easily and in a short time.

The fourth feature of the present invention is that by appropriately selecting the diameter of the bin pole and the mounting angle ψ, the 1cvJ4 tuning sensitivity can be freely selected according to the accuracy of the device and the characteristics of the element.

Although the foregoing has illustrated and described one example of the invention, it will be obvious that many modifications may be made by those skilled in the art without departing from the spirit of the invention.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an accelerometer to which Example Z of the deviation detection device according to the present invention is applied, Fig. 2 is a front view of Fig. 1 with the terminal case removed, and Fig. 3 is 1-1 of Fig. 2. A sectional view taken along the line, FIG. 4 is a route map for explaining the present invention. In the figure, (1) is the camera, (2) is the hinge, (4) is the frame, (7) is the torque coil, (8) is the permanent magnet, (
9) is a pole piece, σ0), (101 is a light receiving element, ■) is a light emitting element, (11 is a pickup holder, (A), +221 is a mounting hole, and (B) is a luminous flux, respectively.

Claims (1)

[Claims] 1. A joint, a base to which one end of the joint is fixed, a pendulum fixed to the other end of the joint, and a torquer that generates torque from the base to the pendulum. In order to photoelectrically detect the relative deviation between the base of the accelerometer having the accelerometer and the pendulum, there is provided a deflection detection device having a light emitting element and two light receiving elements attached to the base. a reflective part provided on the surface of the pendulum perpendicular to the movable direction; a pickup holder mounted on the base opposite to the reflective part; Acceleration characterized in that a light emitting element is attached, and the two light receiving elements are attached to the pickup holder with an intersection angle equal to the intersection angle within a plane that includes the optical axis of the light emitting element and the movable direction axis of the pendulum. meter deviation detection device. 2. A patented acceleration set deflection detecting device lf characterized in that a pinhole is provided in the light emitting surface of the light emitting element.