Electrostatic Capacity Type Micro Inclination Sensor Utilizing Dielectric Nano-Particles

We have developed a capacitive inclination sensor 5 mm times 5 mm times 1.5 mm in size, with a linear analog output. The sensor has three features. First, a method is used that increases permittivity by mixing dielectric nanoparticles with dielectric oil. The resulting high permittivity facilitates sensor miniaturization and high performance. Second, the slit structure and the pseudo channel structure are used to reduce the effect of dielectric oil surface tension on the sensor. Third, direct bonding between electrode and resin is used to reduce dispersion in cavity volume. We succeeded in increasing permittivity by 50% by mixing, with dielectric oil, BaTiO3 nanoparticles 30 nm in diameter at a concentration of 15 Vol%. When evaluated, the sensor successfully produced a linear analog output within the range of -45 to +45 deg. Direct bonding using the hydrogen bond enabled electrode attachment to resin without adhesive. From the above results, we judge that it will probably be possible to manufacture a smaller inclination sensor equivalent to the conventional one