Abstract: A pipe having a through-hole of smaller diameter than a pressure port is disposed in the pressure port. Therefore, a volume of the pressure port can be reduced by the thickness of the pipe, thereby improving response of a pressure sensor. Furthermore, there is no need for the pressure port having smaller diameter to be provided by drill processing, so that a volume in the pressure port can be easily adjusted. Accordingly, the volume in the pressure port can be reduced with a simple structure to improve response of the pressure sensor.
Abstract: A processor of a signal processing circuit for calibrating an electro-capacitance pressure sensor includes a coefficient arithmetic section for calculating calibration value and a calibration arithmetic section. The calibration arithmetic section calculates an electro-capacitance ratio between electro-capacitance C1 and C2 detected by an electro-capacitance pressure sensor and conducts a calibration calculation from the electro-capacitance ratio to output a converted pressure value. The processor includes a fundamental arithmetic section for conducting a calculation given by f=(Z−W)/(X−Y) for predetermined arguments X, Y, Z and W input by the coefficient arithmetic section or the calibration arithmetic section and for outputting the calculation result f to the one of the coefficient arithmetic section and the calibration arithmetic section providing the input. The fundamental arithmetic section provides shared calculating for the coefficient calculation and calibration calculation.
Abstract: A self-calibrating sensor includes a sensor element for electrically detecting change in physical amount of a workpiece. A signal output device detects changes of the sensor element to output an electric signal. A processor conducts calibration calculation for the electric signal to adjust to the physical amount of the workpiece. A memory stores calculation results of the processor. The processor includes a calibration value calculating circuit for calculating a calibration value by conducting the calibration calculation based on a predetermined transforming formula and a calibration completion determining circuit for determining whether calculation of the calibration value by the calibration value calculating circuit is completed or not. The presence of the calibration value calculating circuit and the calibration completion determining circuit eliminates the need for connecting to an outside computer through an exclusive line for calculating the calibration value.
Abstract: A pressure sensor (1) having a first terminal (35), the first terminal (35) including a horizontal portion (61) and a vertical portion (62) at an intermediate portion thereof and being elastically deformable. A portion of the first terminal (35) being inserted and soldered to a circuit substrate (33) has a collar portion (63) being abutted around a through-hole (51) of the circuit substrate (33). The first terminal (35) is fixed at a state being pressed to the circuit substrate (33) by the collar portion (63) and being slightly compressed between a base member (32). When the circuit substrate (33) and the base member (32) are spaced apart by circumambient heat, the first terminal (35) can follow by the compressed margin. When the first terminal (35) itself is thermally expanded, the first terminal (35) can follow by an elastic deformation of the horizontal portion (61) and the vertical portion (62).
Abstract: In a pressure sensor chip (10), an extension (42) is provided on a lower glass (40) and a signal receiving portion (50) of a conductive layer is formed from a surface (42A) of an extension (42) to an upper surface (30B) of an upper glass (30). Accordingly, the signal receiving portion (50) does not touch a circuit substrate when the pressure sensor chip (10) is mounted to the circuit substrate and the like, thereby preventing electric failure such as noise pickup of the signal receiving portion (50). Further, since the signal receiving portion (50) is formed by the conductive layer, no particular space for receiving electric potential from a diaphragm is necessary, thereby enabling size reduction of the pressure sensor chip (10). Since an anodic-bonding electrode (83) is disposed on a border (62) and is cut and removed in separating as the pressure sensor chip (10), visual check is not obstructed and contamination by being peeled-off can be prevented.
Abstract: In an electrostatic capacitance type transducer which has a substrate, a movable electrode confrontingly placed to the substrate in a movable manner through a space, a fixed electrode arranged on a detecting face confronting the movable electrode of the substrate, and a signal receiving portion which is conductive with the fixed electrode and derived from the detecting face of the substrate, the fixed electrode and the signal receiving portion are made of metals which are different with each other in their compositions. That is, the fixed electrode is made of metal which has a high corrosion resistance and is not likely to outbreak a hillock, and the signal receiving portion is made of metal which is easy for bonding. Alternatively, both the fixed electrode and the signal receiving portion are made of titanium.