JP3319066B2 - Acceleration detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acceleration sensor for detecting acceleration and speed.

[0002]

2. Description of the Related Art Hitherto, various acceleration sensors for use in motion control or position control or speed sensors for detecting speed by integrating the acceleration with time have been proposed.

As such an acceleration sensor, a mechanical rotary gyro utilizing precession, a laser gyro utilizing the Sagnac effect, a piezoelectric vibrating gyro utilizing Coriolis force, and the like are widely used.

In particular, in recent years, the above-described piezoelectric vibrating gyroscope has a speed of a pointing remote controller in which the operation of picking up a point displayed on a monitor screen of a computer system is easy, and a speed calculated by integrating this acceleration with time. Is used as a detection sensor for detecting the

[0005]

However, in the conventional mechanical rotary gyro, the size of the device becomes large in order to perform a stable precession motion, and as a result, an expensive acceleration sensor is obtained. However, there is a problem that it is suitable only for large-sized equipment mounted on a ship or a ship.

The above laser gyro, for example, a ring laser type gyro is also large and expensive, and the fiber optic type gyro is used as one of medium-sized devices although the device scale is smaller than the above sensor. There is a problem that the price is not cheap.

Further, in the above-described piezoelectric vibrating gyroscope, although the device scale is small, due to its structural limitation,
Since a certain degree of assembly accuracy is required, there is a problem that the price is high.

That is, as described above, the conventional acceleration sensor or velocity sensor has a problem that it is a high-priced sensor because the device scale is slightly large, the structure is complicated, and strict assembly accuracy is required. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an acceleration sensor that is small in size, has a simple structure, and can detect acceleration at low cost.

[0010]

Acceleration detecting device <br/> of SUMMARY OF THE INVENTION The present invention includes a mass 8, it is disposed around the end faces or mass 8 of the mass 8, pressure sensitive for detecting a change in pressure Conductive member 6
a, and 6b, the pressure-sensitive conductive members 6a, a change in pressure in 6b given
Obtain the elastic members 4a, a 4b, the support member 3a which is arranged in the outermost side, and a 3b, the pressure-sensitive conductive members 6a, 6b and bullets
First conductive layers 5a and 5b are arranged between the conductive members 4a and 4b.
Between the mass body 8 and the pressure-sensitive conductive members 6a and 6b .
Conductive layers 7a, 7b are arranged, and first conductive layers 5a, 5b
To the mass body 8 and the elastic member 4 by external pressure.
a of the pressure-sensitive conductive members 6a and 6b which have received the pressure by the
Pressure change is extracted as an output from the second conductive layers 7a and 7b.
It is characterized by doing .

The elastic members 4a, 4b can be arranged on at least a part of the outside of the pressure-sensitive conductive members 6a, 6b.

[0012]

In the acceleration sensor having the above structure, the second conductive layer 7
By extracting the electrical resistance values of the pressure-sensitive conductive members 6a and 6b by using a and 7b, it is possible to detect acceleration at a small size, with a simple structure, and at low cost.

The elastic members 4a and 4b are arranged at least partially outside the pressure-sensitive conductive members 6a and 6b.
By applying an external pressure to the a and 6b to increase the change in the electrical resistance of the pressure-sensitive conductive members 6a and 6b due to the acceleration, more reliable acceleration detection is possible.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 relate to an embodiment of the present invention. FIG. 1 is a cross-sectional view showing a configuration of an embodiment of the acceleration sensor of the present invention. FIG. 2 explains the operation of the acceleration sensor of FIG. FIG. 3 is an external view showing an external appearance of the acceleration sensor of FIG. 1, and FIG. 4 is a block diagram showing a configuration of a main part of an AV system using the acceleration sensor of FIG.

As shown in FIG. 3A, the acceleration sensor 1 according to the present embodiment comprises a square tube frame 2 having a square cross section.
Support members 3a and 3b are integrally attached to both end surfaces of the frame. As shown in FIG. 1, the inside of the elastic member 4a, 4b composed of a spring or the like respectively attached to the support members 3a, 3b, and the elastic member 4 via first conductive layers 5a, 5b. The pressure-sensitive conductive members 6a and 6b whose electric resistance values change according to the external pressure applied to the pressure-sensitive conductive members 6a and 6b, respectively, are provided to the pressure-sensitive conductive members 6a and 6b via the second conductive layers 7a and 7b. A mass body 8 having a large inertia made of a metal or a mineral, and the mass body 8 is disposed so as to be movable in the axial direction. The pressure-sensitive conductive members 6a and 6b are arranged depending on the position of the mass body. The elastic force from the elastic members 4a and 4b is changed and pressed. Although the elastic member is configured by a spring, it may be configured by an elastic resin or the like.

The operation of the acceleration sensor according to the present embodiment having the above-described configuration will be described. In this acceleration sensor 1, the resistance values of the pressure-sensitive conductive members 6a and 6b are Ra and Rb, the second conductive layers 7a and 7b are externally connected, and a constant voltage E is applied between the first conductive layers 5a and 5b. When the voltage is applied, as shown in FIG.
The differential outputs V of the pressure-sensitive conductive members 6a, 6b are output from the conductive layers 7a, 7b. Normally, when no force is particularly applied to the acceleration sensor 1, the members constituting the acceleration sensor 1 are mechanically stable, and the pressure-sensitive conductive members 6a, 6
The differential output V of b is stable while maintaining substantially the center value (V = E / 2 = V0).

In FIG. 1, the acceleration sensor 1
Is moved upward (U direction), for example, the mass body 8
It moves slightly under force (direction D). Therefore,
At this time, the pressure-sensitive conductive member 6a slightly extends, and its electric resistance value Ra increases. On the other hand, at this time, the pressure-sensitive conductive member 6
b is slightly compressed and its electrical resistance Rb decreases.
As a result, at this time, the differential output V of the pressure-sensitive conductive members 6a and 6b decreases.

Next, in FIG. 1, when the acceleration sensor 1 is moved downward (in the direction D), a phenomenon opposite to the above occurs, and the above-mentioned differential output V rises.

In the above description, the differential output V when a force is applied to the acceleration sensor 1 has been described in the case where a vertical force is applied. The same holds true.

Although the constant voltage source is connected between the first conductive layers 5a and 5b, the present invention is not limited to this. As shown in FIG. 2B, a constant current source is connected between the first conductive layers 5a and 5b. May be connected. Further, as shown in FIG. 2C, the first conductive layers 5a and 5b are divided by a resistor R, and a differential output is detected based on the divided potential to detect only a drift component. Alternatively, as shown in FIG. 2D in this case, a configuration may be employed in which a current interruption source is connected instead of the constant voltage source.

As described above, according to the acceleration sensor 1 of this embodiment, when at least one force in the forward and reverse directions is applied, the mass body 8 moves, whereby the pressure-sensitive conductive members 6a and 6b expand and contract. Since the resistance value is changed, by detecting the change in the resistance value as the differential output V of the pressure-sensitive conductive members 6a and 6b, the direction and magnitude of the acceleration can be detected simply, compactly and inexpensively.

In the above description, the operation of detecting acceleration in only one-dimensional direction by the acceleration sensor 1 has been described. However, by using two or three acceleration sensors 1 and arranging them in directions orthogonal to each other, It goes without saying that a three-dimensional acceleration sensor or a three-dimensional acceleration sensor can be realized.

As for the two-dimensional acceleration sensor and the three-dimensional acceleration sensor, in addition to the above-described structure, as shown in FIG. 3B or FIG. Other members are separately provided, and one set is disposed in a direction perpendicular to the above-described pressure-sensitive conductive member and the mass body 8 or
By arranging two or more sets, the two-dimensional acceleration sensor 20 or the three-dimensional acceleration sensor 30 can realize an acceleration sensor capable of simultaneously detecting in any of horizontal and vertical directions or in more directions.

In FIG. 3A, the sensor 1 has a prismatic outer shape. However, the shape of the sensor is not limited to a prism, and it is a matter of course that the acceleration sensor can be formed in any shape such as a cylinder or a triangular prism. .

As shown in FIG. 3D, the two-dimensional acceleration sensor includes a cylindrical mass body 41 concentrically from the center, a cylindrical conductive layer 42 covering the mass body 41,
A cylindrical pressure-sensitive conductive member 43 that covers the conductive layer 42, a cylindrical conductive layer 45 including a plurality of conductors 44 that cover the pressure-sensitive conductive member 43, and a cylindrical shape that covers and presses the conductive layer 45. The two-dimensional sensor 40 having a columnar shape in which the elastic members 46 are sequentially arranged and the outermost peripheral surface is covered with the support member 47 may be used. In this case, the plurality of conductors 44 provided on the cylindrical conductive layer 45
By detecting the output voltage from, it is possible to easily calculate what kind of force the mass body has received vertically and horizontally.

As shown in FIG. 3 (e), the three-dimensional acceleration sensor has a mass 51, a conductive layer 52 covering the mass 51, and a pressure-sensitive layer covering the conductive layer 52. A conductive layer 53 having a plurality of conductors 54 covering the conductive member 53 and the pressure-sensitive conductive member 53, and an elastic member 56 covering and pressing the conductive layer 55 are sequentially arranged, and the outermost peripheral surface is covered with a support member 57. Spherical three-dimensional sensor 5
It may be 0. In this case, by detecting output voltages from the plurality of conductors 54 provided on the cylindrical conductive layer 55,
It is possible to easily calculate what kind of force the mass body has received in the vertical and horizontal directions.

In FIG. 1, the second conductive layers 7a and 7b
Are independent electrodes, but they may be shared with the mass body 8. That is, an electrode may be attached to the surface of the mass body 8 by various methods such as plating and vapor deposition. Alternatively, electrodes may be attached to the surfaces of the pressure-sensitive conductive members 6a and 6b by various methods such as plating and vapor deposition. Similarly, the second conductive layers 7a and 7b are also independent electrodes, but may be those in which the electrodes are attached to the surfaces of the pressure-sensitive conductive members 6a and 6b by various methods such as plating and vapor deposition. Or elastic member 4
a, 4b may be integrated.

Although the pressing is performed by using the two elastic members 4a and 4b, the pressing may be performed by one of the elastic members. As the material of the pressure-sensitive conductive members 6a and 6b used in the present embodiment, various types such as various pressure-sensitive conductive rubbers, piezoelectric elements, and semiconductor piezoelectric elements can be applied.

Incidentally, the acceleration sensor 1 of the present embodiment is
It can be used for the following AV system. That is, as shown in FIG.
It comprises a remote control unit 60a and an image display unit 60b. Now, for example, when moving a marker displayed on the display monitor 68, the marker is picked by the remote controller 60a, and when the remote controller 60a is moved in the moving direction, a force acts on the acceleration sensor 1. Occurs. Therefore, in the remote control unit 60a, the acceleration signal 71 from the acceleration sensor 1 is time-integrated by the time integration circuit 61, and the speed signal 72 obtained by the time integration circuit 61 is further time-integrated by the time integration circuit 62 to obtain the moving distance signal. Get
By inputting any one of these signals, for example, a moving distance signal, to the remote control transmitter 63, the signals are modulated and transmitted to the image display unit 60b by infrared rays or radio waves.

In the image display section 60b, the remote control receiver 6
In step 5, the transmission signal from the remote control transmitter 63 is received, and the demodulation circuit 66 demodulates the moving distance signal 73 and calculates the moving position of the marker on the display monitor. The moving position of the marker on the display monitor 68 calculated by the mixer 67 is mixed with a video signal for creating a display image, so that the marker is displayed at a desired position.

As described above, in the AV system including the acceleration sensor of the present embodiment, by moving the acceleration sensor at hand, the marker can be moved on the displayed screen, and operations such as selection of various functions can be performed. .

[0032]

As described above, according to the present invention, acceleration detection is performed.
According to the device , the pressure change of the pressure- sensitive conductive member is extracted from the second conductive layer by applying power to the first conductive layer, so that the device is small, simple in structure, and inexpensive. There is an effect that acceleration can be detected.

Further, by disposing an elastic member on at least a part of the outside of the pressure-sensitive conductive member, a change in the electric resistance value of the pressure-sensitive conductive member due to acceleration is increased by applying an external pressure to the pressure-sensitive conductive member. Therefore, there is an effect that more reliable acceleration detection can be performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of an embodiment of an acceleration sensor according to the present invention.

FIG. 2 is an equivalent circuit diagram for explaining the operation of the acceleration sensor of FIG.

FIG. 3 is an external view showing the external appearance of the acceleration sensor of FIG. 1;

FIG. 4 is a block diagram showing a configuration of a main part of an AV system using the acceleration sensor of FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 acceleration sensor 3a, 3b support member 4a, 4b elastic member 5a, 5b first conductive layer 6a, 6b pressure-sensitive conductive member 7a, 7b second conductive layer 8 mass

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-244863 (JP, A) JP-A-4-350567 (JP, A) JP-A-2-306168 (JP, A) JP-A-1- 202670 (JP, A) JP-A-5-10966 (JP, A) JP-A-49-121576 (JP, A) JP-A 61-92590 (JP, U) JP-A 53-91876 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) G01P 15/02-15/18

Claims (7)

(57) [Claims] An acceleration is detected by detecting an external pressure.
In the acceleration sensor, the mass body , a pressure-sensitive conductive member that is disposed at both end surfaces of the mass body or around the mass body, and detects a change in pressure , and applies a change in pressure to the pressure- sensitive conductive member. the first conductive layer between the elastic member, and a support member disposed at the outermost side, and the elastic member and the pressure-sensitive conductive member to provide
It was placed, a second conductive layer between the pressure-sensitive conductive member and said mass body
And applying a power to the first conductive layer, and applying an external pressure to the material.
The pressure-sensitive conductive part under pressure by the monomer and the elastic member
Extracting the pressure change of the material from the second conductive layer as an output
Acceleration detecting device, characterized in that that. 2. The acceleration detecting device according to claim 1 , wherein the pressure-sensitive conductive member is a conductive rubber or a semiconductor pressure-sensitive element. 3. The acceleration detecting device according to claim 1 , wherein the components of the mass body, the pressure-sensitive conductive member, and the support member are linearly arranged. 4. The acceleration detection device according to claim 3 , wherein the mass body is common, and the constituent elements of the pressure-sensitive conductive member and the support member are arranged in two orthogonal straight lines. 5. The acceleration detection device according to claim 3 , wherein the mass body is common, and the constituent elements of the pressure-sensitive conductive member and the support member are arranged in three orthogonal straight lines. 6. form the mass into a cylindrical shape, wherein the components of the pressure-sensitive conductive member and the support member to claim 1, characterized in that arranged on the mass body and the concentric cylindrical Acceleration detection device . 7. The acceleration according to claim 1 , wherein the mass body is formed in a spherical shape, and the components of the pressure-sensitive conductive member and the support member are arranged in a spherical shape concentric with the mass body. Detection device .