Compositions – Electrically conductive or emissive compositions – Carbide containing
Reexamination Certificate
1999-01-19
2001-10-16
Kopec, Mark (Department: 1751)
Compositions
Electrically conductive or emissive compositions
Carbide containing
C252S521400, C252S515000, C252S518100, C073S763000, C073S777000
Reexamination Certificate
active
06303055
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a composition of a high sensitivity sensor for detecting mechanical quantity of force, pressure, torque, speed, acceleration, position, displacement, impact force, weight mass, vacuum degree, rotating force, vibration, noise, etc. with high sensitivity.
2. Description of Related Art
An electrical resistance strain gauge, silicon of a semiconductor, etc. are conventionally used as a component of a sensor for detecting mechanical changing amounts of force, pressure, torque, speed, acceleration, position, displacement, impact force, weight mass, vacuum degree, rotating force, vibration, noise, etc. through strain (stress).
In particular, the semiconductor silicon is applied to an impact tester, a displacement gauge, a pressure converter, an accelerometer, a compact pressure gauge for an organism, a flow meter, a gas pressure gauge, etc. as a strain gauge element of high sensitivity in various fields such as general industry, automobiles, medical care, etc.
Silicon (Si) is generally used as a sensor for detecting mechanical quantity using the semiconductor. A phenomenon in which an electrical resistance value of the semiconductor is changed by strain caused by applying external force to the silicon is used.
However, because of the lower sensitivity of the sensor constituted of a conventional material, it is difficult to obtain a sensor for detecting mechanical quantity having a required accuracy and high sensitivity which are used as a micro pressure sensor of an organismic system, etc., a combustion pressure sensor and a pressure sensor for a hydraulic device.
SUMMARY OF THE INVENTION
In consideration of such problems, the object and an aspect of the present invention is to provide a composition of a high sensitivity sensor for detecting mechanical quantity in which a sensor capable of detecting a mechanical quantity can be constructed with a high sensitivity (high gauge ratio).
Next, a second aspect of the invention is a composition of a high sensitivity sensor for detecting mechanical quantity comprising:
an insulating matrix material;
a conductive path formed by discontinuously dispersing second phase particles of a conductor or a semiconductor into the insulating matrix material at an interparticle distance from 0.001 to 1 &mgr;m;
wherein an average distance A between the second phase particles parallel to a loading direction of mechanical quantity to be detected is smaller than an average distance B between the second phase particles perpendicular to the loading direction;
thereby imparting the high sensitivity in the mechanical quantity to the composition.
The composition of a high sensitivity sensor for detecting mechanical quantity in the second aspect of the invention comprises the insulating matrix material and the conductive path which is constituted of discontinuously dispersing the second phase particles into this insulating matrix material at the interparticle distance from 0.001 to 1 &mgr;m.
In this composition of a high sensitivity sensor for detecting mechanical quantity, the average distance A between the second phase particles in the loading direction of the detected mechanical quantity is smaller than the average distance B between the second phase particles in the direction perpendicular to the loading direction. Accordingly, a large electrical resistance changing rate can be also obtained with respect to a small strain although its detailed mechanism is yet unclear. Therefore, strain-electrical resistance effects with high sensitivity can be obtained. Therefore, it has become clear that a gauge ratio is greatly increased in comparison with the conventional material.
Therefore, sensitivity of the sensor for detecting mechanical quantity manufactured by the composition of the sensor in the second aspect of the invention is greatly improved. Accordingly, a sensor for detecting mechanical quantity with a high accuracy can be obtained.
As mentioned above, in accordance with the second aspect of the invention, it is possible to provide a composition of a high sensitivity sensor for detecting mechanical quantity capable of constituting a sensor capable of detecting the mechanical quantity with high sensitivity.
Next, a third aspect of the invention is a composition of a high sensitivity sensor for detecting mechanical quantity comprising:
an insulating matrix material;
a conductive path formed by discontinuously dispersing second phase particles of a conductor or a semiconductor into the insulating matrix material at an interparticle distance from 0.001 to 1 &mgr;m;
wherein the insulating matrix comprises crystal particles which are oriented and aligned in a loading direction of mechanical quantity to be detected;
thereby imparting the high sensitivity in the mechanical quantity to the composition.
The composition of a high sensitivity sensor for detecting mechanical quantity in the third aspect of the invention comprises the insulating matrix material and the conductive path which is constituted of discontinuously dispersing the second phase particles into this insulating matrix material at the interparticle distance from 0.001 to 1 &mgr;m.
This composition of a high sensitivity sensor for detecting mechanical quantity is in a state in which the crystal particles constituting the above insulating matrix are oriented along the loading direction of the detected mechanical quantity. In other words, an anisotropic property is given to a dispersion mode of the second phase particles.
Accordingly, the distance between the second phase particles in the loading direction of the detected mechanical quantity can be set to be smaller than that in a direction perpendicular to the loading direction although its detailed mechanism is unclear.
Further, a change in the interparticle distance in the loading direction caused by a stress load can be increased in comparison with that in the direction perpendicular to the loading direction. Namely, a change in electrical resistance value in the stress loading direction can be set to be larger than that in the direction perpendicular to the stress loading direction.
Thus, a large electrical resistance changing rate can be also obtained with respect to a small strain and strain-electrical resistance effects with a high sensitivity can be obtained. Accordingly, it has become clear that a gauge ratio is greatly increased in comparison with the conventional material.
Therefore, sensitivity of the sensor for detecting mechanical quantity manufactured by the composition of the sensor in the third aspect of the invention is greatly improved. Accordingly, a sensor for detecting mechanical quantity with a high accuracy can be obtained.
As mentioned above, in accordance with the third aspect of the invention, it is possible to provide a composition of a high sensitivity sensor for detecting mechanical quantity capable of constituting a sensor capable of detecting the mechanical quantity with a high sensitivity.
REFERENCES:
patent: 4203088 (1980-05-01), Sado et al.
patent: 4793193 (1988-12-01), Borgudd
patent: 5645929 (1997-07-01), Debe
patent: 5656218 (1997-08-01), Lin et al.
patent: 5835841 (1998-11-01), Yamada et al.
patent: 6143207 (2000-11-01), Yamada et al.
patent: 60-18081 (1985-05-01), None
patent: 1-252582 (1989-10-01), None
patent: 2-229765 (1990-09-01), None
Asai Mitsuru
Kamiya Nobuo
Yamada Katsunori
Kabushiki Kaisha Toyota Chuo Kenkyusho
Kopec Mark
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
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