Yokogawa Electric Corporation

Kajima Corporation

Masaki Shioya

Hideaki Matsumura

Kenichi Takeda

Naoyuki Fujimoto

Masato Yamaji

Masuo Hanawaka

Iwao Nakanishi

Takumi Ooe

Minoru Midorikawa

Yota Furukawa

Noriyasu Sagara

Yuji Tsubota

Takumi Oe

A wireless relay device for relaying encrypted data via a wireless network according to one aspect of the present invention includes a relay controller and an encryption processor. The relay controller is configured to relay a first data to a predetermined relay destination as a second data via the wireless network. The first data is transmitted to the wireless relay device via the wireless network and is addressed to the wireless relay device. The encryption processor is configured to decrypt the first data into a decrypted first data and to input the decrypted first data into the relay controller, and encrypt the second data to be relayed by the relay controller.

Wireless relay device, wireless communication system, and wireless relay method

A wireless device that performs an operation based on setting information includes a wireless communicator configured to perform wireless communication over a wireless network, a near field communicator comprising a memory storing the setting information and configured to perform transmission and reception of the setting information stored in the memory by near field communication, and a controller configured to control at least the wireless communicator.

Wireless device, gateway apparatus, and wireless communication system

A facility control monitor method and a facility control monitor apparatus capable of visually tracing a control logic and easily finding a cause of an operation trouble caused by the control logic. The facility control monitor method monitors control performed by a control device included in a facility having a controllable device, the control device for controlling the controllable device, a setting device for transmitting a setting control value to the control device, and a sensor for transmitting an operation state measurement value of the controllable device to the control device. Processes of control performed by the control device are stored. When an arbitrary date and time is specified by a trace controller (), predetermined control steps of the specified date and time and after are displayed in a flowchart on a control flow display unit.

Facility control monitor method and facility control monitor apparatus

A switching power supply comprising a main converter that turns ON and OFF a DC current applied to a primary winding of a main transformer by a main switching element and outputs a main output voltage to a secondary circuit by rectifying and smoothing current induced in a secondary winding; an error amplifier generating an error voltage between the main output voltage and a first reference voltage; an over-voltage protection circuit that generates an over-voltage protection signal when the main output voltage exceeds a second reference voltage; a PWM circuit to control a drive signal for the main switching element to minimize error voltage outputted by the error amplifier; and a shut-down execution circuit that stops the main converter operation when the over-voltage protection signal is generated; wherein are provided a device to superimpose the over-voltage protection signal on the error signal of the main output voltage induced in the secondary winding and to transmit the superimposed signal to the primary circuit after isolating the superimposed signal with a photo-coupler; and a primary control circuit that detects an error signal transmitted via the photo-coupler by dividing the error signal into three levels of stop range, normal operation range, and abnormal operation range, and rapidly stop operation of the main converter when the error signal value is deflected to the stop range or the abnormal operation range due to failure of the photo-coupler, thereby resulting in improved reliability of the switching power supply.

Switching power supply using a single isolating element to facilitate

A pulse width control IC circuit that greatly reduces price, increases packaging density,and improves reliability for switching power supply units, wherein the IC circuit is on a single chip and includes a main converter control section that controls the ON and OFF actions of a main switch outside the IC, an output MOSFET, and an auxiliary converter control section that controls the ON and OFF actions of the output MOSFET.

Pulse width control IC circuit and switching power supply unit

A switching power supply apparatus wherein a main converter turns 'on' and 'off' a DC current applied to a primary winding of a main transformer using a main switching element and outputs a main output voltage to the secondary side after rectifying and smoothing current induced in a secondary winding; an error amplifier generates an error voltage between the main output voltage and a first reference voltage; a PWM control circuit outputs an on-off control signal for the main switching element so that the error voltage is minimized; a photo coupler receives the error voltage and provides an output to the PWM control circuit; an over-voltage protection circuit generates an over-voltage protection signal when the main output voltage exceeds a second reference voltage; an on-off circuit outputs either a high level potential or a common level potential depending on whether the power is to be turned 'on' or 'off'; a shut down latch circuit outputs a shut down signal when the over-voltage protection signal represents an over-voltage state; and a shut down implementation circuit holds the input voltage to the photo-coupler at a value which suppresses input to the photo-coupler when a signal from the on-off circuit specifies power off or when the shut down signal from the shut down latch circuit is effective; whereby only a single isolator is required in the apparatus.

Switching power supply unit

A switching power supply for controlling an output voltage to a constant value with respect to fluctuations in input or in load, wherein are provided a DC power supply; two dividing capacitors connected in series to both ends of the DC power supply; two semiconductor switches connected in series to both ends of the DC power supply; a transformer having a primary winding, one end of which is connected to a connecting point of the two dividing capacitors; and a T type circuit comprising two inductors connected in series between the connecting point of the two semiconductor switches and the other end of the primary winding; and a capacitor connected between the connecting point of the two inductors and the other end of the primary winding. The control characteristics of the switching power supply are improved by reducing the dependency of the output voltage on fluctuations in the load.

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Tokyo, Japan

Masaki Shioya