JPS601427Y2 - Acceleration sensor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an acceleration sensor used in a vehicle.

More specifically, a transparent arc-shaped tube or the like is filled with permeable oil or the like, and an impermeable sphere is housed inside the tube so as to be able to roll freely. A set of light-emitting elements and light-receiving elements are arranged, and a space between the elements that is blocked by the displacement of the sphere due to the acceleration of the vehicle is opened,
The present invention relates to an acceleration sensor that obtains a signal by inputting a light emitting element to a light receiving element, and uses the signal to control, for example, a shock absorber forming a suspension system of a vehicle.

For example, when a lateral G is applied to the vehicle body when the vehicle is turning, and if this exceeds a certain level in relation to the speed, one side will sink inside and outside the turn and the other will rise due to the relationship with centrifugal force.

In this case, it is possible to prevent sinking by cutting off the fluid system of the shock absorber on the sinking side or by controlling the tension to obtain a high damping force.

The above rolling control etc. can be performed by detecting the lateral acceleration 61 of the vehicle, and an attempt is made to control the shock absorber by detecting this acceleration.

By the way, the above-mentioned acceleration is conventionally detected as follows.

That is, the first method is to add a mass to the tip of a thin piece as an acceleration sensor and detect the bending stress of the thin sheet according to the acceleration using a strain gauge. An acceleration sensor is proposed that detects the electric charge generated according to the distributed acceleration of the mass.

All of these are desirable because they allow highly accurate measurements over a wide acceleration range, but on the other hand, the cost of the acceleration sensor itself is extremely high, and when it is attached, the cost of the vehicle including the attached equipment increases, making it difficult to reduce costs. The change in resistance or electric charge that occurs in the acceleration sensor is weak, requiring a special and expensive dedicated amplifier, and since it is intended to be controlled by acceleration, a separate logic circuit device such as a judgment mechanism is required. In addition to the above, the cost will increase.

The inventors of the present invention have devised the present invention in order to solve the above-mentioned problems with conventional acceleration sensors and to obtain an acceleration sensor that is useful, inexpensive, and capable of easily detecting acceleration.

The purpose of this invention is to install an impermeable sphere within an arc-shaped permeable tube filled with a permeable liquid so that it can be moved freely, and to open up the space between the receiving and emitting elements that were previously blocked by moving the sphere. It is an object of the present invention to provide an acceleration sensor which detects acceleration using optical input and uses this input to obtain a control signal for a shock absorber or the like.

In addition, the present invention not only allows reliable detection of acceleration by not forming an arcuate space with a transparent tube, but also detects the magnitude of acceleration by providing multiple sets of receiving and emitting elements. - It is possible to perform on/off control based on acceleration detection using a set or multiple sets of receiving/emitting elements, and furthermore, it is possible to perform stepwise control according to acceleration, and the above can be planned at low cost with a simple structure. When performing the above operations by disposing a sphere within a sphere within a liquid, the liquid buffers minute vibrations, allowing accurate detection of only the required acceleration, and preventing leakage of the liquid. It has advantages such as complete prevention.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The drawing is a schematic explanatory diagram showing the present invention, in which 1 is a transparent member,
For example, it is an arc-shaped pipe made of glass, synthetic resin, etc., and the pipe 1 has a central part that curves downward at the bottom and symmetrically curves upward at the left and right sides to form a sealed circular tubular space inside. is forming.

Inside the pipe 1 is a permeable, i.e. transparent or translucent, liquid;
For example, a viscous oil 2 is hermetically sealed, and an impermeable sphere 3 such as a steel ball is placed inside a pipe 1 containing this oil 2.
The sphere 3 is installed in the interior so that it can be moved freely, and the sphere 3 is at rest at the bottom of the arc at the center of the pipe 1 due to the action of gravity during normal times when no acceleration is applied.

The L pipe 1 is disposed at the center of the vehicle in the left-right direction so that its length is aligned with the width direction of the vehicle, that is, the left-right direction.

At the rest position of the sphere 3 of the pipe 1, that is, at the center thereof, a light emitting element 4 is disposed on top, and light receiving elements 6 are disposed on the father and son sides facing the light emitting element 4.

Below the light emitting element 4 is a slit plate 5 having a slit 5a.
However, a slit plate 7 having a slit 7a is disposed above the light receiving element 6.

A transparent molding member 8 covers the pipe 1 and the light emitting/receiving elements.

The light emitting element 4 is supplied with power from the power supply circuit, and the light receiving element 6 is connected to the control system directly or indirectly via an amplifier or the like.

In the above, the figure shows a normal state in which the lateral acceleration is below a predetermined value, and the sphere 3 is located in the oil 2 of the pipe 1 at the lowest central part due to the action of gravity.

Lateral acceleration occurs when the vehicle turns by steering to the right or left, and when the lateral acceleration exceeds a predetermined value, the sphere 3 resists the viscosity of the oil 2, the mass of the sphere 3, and the gravitational force in the pipe 1. It will roll to the right or left.

As a result, the light emitting element 4, which was blocked by the sphere 3 when it was at rest,
The light reaches the light receiving element 6 and is input to the light receiving element 6.

That is, the receiving and emitting elements that were blocked by the sphere 3 are turned on when the space between them is opened due to their transfer at a predetermined acceleration or higher, and this input is output as an electrical signal and input to the control system. This is operated under control.

For example, if the device to be controlled is a shock absorber, the above signal can be used to drive a solenoid or the like to increase the damping force by switching the orifice attached to the shock absorber and for generating hydraulic damping force, so that the damping force can be reduced when turning, etc. It is possible to perform controls such as preventing the container from sinking and suppressing excessive rolling.

In the illustrated example above, one set of receiving/emitting elements 6, 4 is provided, but in addition to this, one set or more may be provided on the left and right, thereby opening and closing multiple sets of receiving/emitting elements, and thereby adjusting the lateral acceleration and the sphere. It is possible to detect the magnitude and direction of acceleration caused by the relative movement of and send this as a signal to control the control system in response to the acceleration.

As is clear from the above, according to the present invention, the space between the receiving and emitting elements is opened and closed by the movement of the sphere due to the acceleration, and control is performed by obtaining a control signal using light. First, acceleration can be detected reliably and easily. It is possible to ensure the accuracy of detection motion, and since it uses receiving and emitting elements, it requires minimal amplifiers, etc., and can be provided with a simple structure and low cost with a minimum number of parts, making it suitable for vehicles. A highly practical acceleration sensor can be obtained.

Furthermore, the receiving and emitting elements are inexpensive, and by using multiple sets of them to construct a simple detection and control circuit, the magnitude and direction of acceleration can be easily detected, and control can be performed according to acceleration. In addition, the sphere, which is the acceleration detection medium, is filled with oil or the like, which provides a buffering effect, absorbs minute vibrations, and prevents the sphere from malfunctioning, making it possible to obtain a highly accurate acceleration sensor.

Furthermore, since the sealed space in which the sphere rolls is formed in an arc shape using a transparent tube, it is possible to cause the sphere to move accurately in response to the magnitude of acceleration, and it is also possible to accurately adjust the movement of the sphere to the magnitude of the acceleration to be detected. The curvature of the arcuate transparent tube can be varied accordingly.

In addition, since it is made of molded material, it is easy to assemble multiple sets of light emitting and light receiving means, and together with the above-mentioned transparent tube, the overall structure is strong against vibrations, etc., and prevents leakage of the above-mentioned oil, etc. It can also be completely prevented, and the practical effects are remarkable.

[Brief explanation of the drawing]

The drawings are schematic illustrations showing one embodiment of the present invention. In the drawing, 1 is a pipe which is a space, 2 is a liquid, 3 is a sphere,
4 is a light emitting element, and 6 is a light receiving element.

Claims (1)

[Claims for Utility Model Registration] An acceleration sensor comprising an impervious sphere movably housed in a closed space filled with a transparent liquid, and a set of a light emitting means and a light receiving means provided at opposing positions facing the space. , the sealed space is formed by an arc-shaped transparent tube, and a plurality of sets of the light emitting means and the light receiving means are arranged at the lowest position of the sealed space around the transparent tube and at other positions along the sealed space. An acceleration sensor characterized by being integrally molded with mold material.