Yamatake-honeywell Co., Ltd.

Yamatake Honeywell

Yamatake Corporation

Masato Kuroda

Masatoshi Fujiwara

Shinichi Akano

Sakae Ishikawa

Tsutomu Goto

Yasuo Kumeda

Fumio Nagasaka

Yoshiro Tanaka

Tatsuhide Shiga

Norikazu Wada

Hiroshi Watanabe

Ryoichiro Matsumoto

A field apparatus for controlling a controlled element includes a diagnosis unit for diagnosing abnormality of the field apparatus and/or the controlled element and a bidirectional digital communication device to send a digital signal which shows a diagnosis result to outside and to receive a digital signal from outside in order to execute a control of the controlled element. Other predetermined functions are effected based on a command signal in the form of an analog signal received from outside by a analog communications device of the apparatus. Electric power for operation is supplied through a switching means that can switch either a electric power that is supplied by the analog communications device or a electric power that is supplied by the bidirectional digital communication device.

Field apparatus

An electropneumatic positioner includes an electropneumatic converter, an pilot relay, an operating unit, and a sensor. The electropneumatic converter includes a yoke having central and side leg portions, a permanent magnet arranged on the central leg portion, a pair of coils for exciting the side leg portions to have opposite polarities, a nozzle embedded in one side leg portion to spray air having predetermined pressure, a stopper arranged on the other side leg portion, and a flapper arranged to be swingable on a fulcrum near the central leg portion and serving to change a nozzle back pressure by controlling the amount of air sprayed from the nozzle in accordance with a swing. The electropneumatic converter receives a duty signal, as a driving signal for the coils, which signal is obtained by converting a deviation between an input signal and a feedback signal into a duty. The flapper is set to be parallel to the yoke when the deviation between the input signal and the feedback signal is zero. The pilot relay receives a nozzle back pressure and amplifies an air pressure. The operating unit converts an output air pressure from the pilot relay into a mechanical displacement amount. The sensor detects the displacement amount obtained by the operating unit and generates a feedback signal.

Electropneumatic positioner

The present invention uses an input multiplexer for selecting a plurality of input signals, a fluid multiplexer for selectively delivering a control output to a plurality of devices to be controlled, a detecting multiplexer for selecting detected signals indicative of the condition in which the devices respond, a controller for controlling the multiplexers for successive and repeated selective operations, for effecting a controlling arithmetic operation on an input signal fed through the input multiplexer and a detected signal fed through the detecting multiplexer, and for delivering a control signal resulting from the controlling arithmetic operation, and an electropneumatic transducer for converting the control signal to a pneumatic pressure and issuing the pneumatic pressure as an input to the fluid multiplexer.

Multicontrol process control system

An electro-pneumatic pressure converter including a switching valve having at least one plate-like piezoelectric element, which is supported at one end in a cantilever manner inside a sealed chamber and a distal end portion of which moves upon application of a voltage, at least two pressure nozzles which are opened and closed upon displacement of the piezoelectric element, and an output channel extending from the sealed chamber to an external portion; a pilot relay for converting a pneumatic pressure signal from the output channel into a pneumatic pressure signal; a pressure sensor for converting the output pressure signal of the pilot relay into an electrical signal; pulse width modulating means for supplying a pulse-width modulation signal corresponding to a difference between the electrical signal from the pressure sensor and an external input signal to the plate-like piezoelectric element of the switching valve; a power supplycircuit for obtaining a predetermined voltage from the external input voltage to supply a voltage to respective portions of the converter; and means for monitoring the external input voltage and inhibiting an output of the switching valve when the external voltage is decreased below a predetermined value smaller than a normal operating range.

Electro-pneumatic pressure converter

A switching valve has at least one plate-shaped piezo-electric element having a free end which is supported in a sealed chamber, at least two fluid directing nozzles arranged to be opened or closed due to the position of the free end of the piezo-electric element and a fluid output passage communicating outwardly from said sealed chamber. An electric-pressure converter uses the switching valve, a pilot relay for converting a fluid pressure signal delivered from the output passage into a standard air pressure signal, a pressure sensor for converting the pressure signal from said pilot relay into an electrical signal, pulse-width modulating means for providing a pulse-width modulated signal, which corresponds to the deviation between the electrical signal from the pressure sensor and an external reference electric signal, for energizing the plate-shaped piezo-electric element in the switching valve.

Switching valve and an electro-pneumatic pressure converter utilizing

An electromagnetic flowmeter uses a cylindrical inner tube including an electrode, an excitation coil and an inner portion of an electrical connector with the inner portion being located on an outer circumferential surface of the tube and electrically connected to the electrode and the coil, an outer tube housing the inner tube along its axis and having an access opening extending transversely through the outer tube housing and an electrical connector support externally inserted through the access opening for supporting an outer portion of the electrical connector to selectively mate with the first portion of the connector to provide separate electrically conductive paths through the connector for connections to the electrode and the excitation coil.

Electromagnetic flowmeter

An electromagnetic flowmeter for electrically measuring a flow rate of a fluid flowing through a measuring pipe has an insulating lining which lines the measuring pipe. A conductive powder is mixed in parts of the insulating lining. The measuring pipe is short-circuited with the fluid through the conductive powder, thereby providing a reference potential of detected current corresponding to the flow rate of the fluid.

Growing community of inventors

Fujisawa, Japan

Masato Kuroda