Murata Mfg. Co., Ltd.

Murata Manufacturing Co., Ltd.

Tetsuo Oosawa

Noboru Masuda

Kenji Tomaki

Michihiro Murata

Yasutaka Fujii

It is an object of the present invention to prevent variations in sensitivity of the sensor circuits of the respective channels by equalizing the power of oscillation frequency signals to be distributed/supplied from one oscillation circuit to the sensor circuits of the respective channels. Multi-channel sensor circuits are arranged with a common oscillation circuit. A high-impedance conversion circuit is connected to the output terminal of the oscillation circuit. A first impedance matching circuit for performing impedance matching of resonance circuits of the respective channels with reference to the oscillation circuit is arranged on the output side of the high-impedance conversion circuit. Second impedance matching circuits for performing impedance matching of the oscillation circuit with reference to the resonance circuits are connected at the input terminals of the resonance circuits of the respective channels. The first impedance matching circuit is connected to the second impedance matching circuits through coaxial cables.

Apparatus for matching impedance in an electrostatic sensor

Apparatus for detecting thickness which includes an electrode detecting unit including a ground electrode and a detecting electrode. The electrodes oppose each other along a paper path. An oscillating circuit provides an oscillation frequency signal. A resonant circuit, having a resonator independent of the oscillating circuit, has a resonance point which changes in accordance with a change in electro-static capacitance corresponding to a change in paper thickness detected by the electrode detecting unit. A resonant circuit outputs a detection signal corresponding to the change in resonance point. By analyzing this detecting signal, a state of two sheets of paper passing through the path is detected as a change in paper thickness.

Paper thickness detecting apparatus having a resonator with a resonance

Disclosed is a multi-channel electrostatic sensor apparatus including a main oscillation circuit; a plurality of pull-in type sub-oscillation circuits which are adapted to synchronize with the main oscillation circuit to generate sub-frequency signals whose frequency is equal to the main oscillation frequency or a multiple thereof; and a plurality of resonance circuits which are sensitive to any change in exterior capacitance when detected by an associated detector for changing its resonator resonance point with respect to the sub-frequency signal. Positive synchronization of the sub-oscillation circuits with the single main oscillation circuit prevents any adverse effect from being caused by the varying stray capacitance in flexible conductors connecting the sub-oscillation circuits to the main oscillation circuit while allowing the relatively free movement of the video heads of a video system, on which video heads the sub-oscillation circuits and subsequent components are attached.

Multi-channel electrostatic sensor apparatus

Disclosed is a small-sized magnetoresistance element array having a plurality of arranged magnetoresistance elements and provided with excellent operating efficiency which facilitates connection of each magnetoresistance element by virtue of comb terminals and U-shaped terminals provided on the inner walls of the stem. In the magnetoresistance element array, the magnet detectors are positioned at the right three-dimensional position, thereby preventing crosstalk or deviation in the reading timing at the time of reading a magnetic code. Guides are provided on the top walls of the stem so as to regulate the position at which the magnetic detector is secured to the top portion of the magnet. The magnetoresistance element array is used for a magnetic sensor for reading information recorded as a magnetic code from a magnetic code recorded medium such as a magnetic card.

Magnetoresistance element array

A pyroelectric infrared ray detector of the so-called dual structure for detecting an intruder or the like through differential output of two pyroelectric infrared ray detecting elements connected in parallel or series to each other. The infrared ray detector comprises a pair of pyroelectric infrared ray detecting elements having substantially identically directed light receiving surfaces and electrically connected to each other and a shield member arranged in front of the said light receiving surfaces to partially shield the infrared ray detecting elements against incidence of infrared light. The shield member is arranged in a plane extending between the infrared ray detecting elements to separate the same on both sides thereof.

Infrared ray detector

A pyroelectric type detecting device including a converging mirror, a pyroelectric type sensor element for detecting light converged by the converging mirror, an amplifier for amplifying an output signal of the sensor element and a casing for accommodating the sensor element and the amplifier. The sensor element has a window for receiving the light and the casing is rotatably mounted on a portion of the converging mirror such that the window of the sensor element confronts a mirror member of the converging mirror.

Growing community of inventors

Tokyo, Japan

Tetsuo Oosawa