Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Yasuo Koba

Takashi Watanabe

Masahiro Yamamoto

Kouichi Takemura

Aoi Watanabe

Yuji Fujii

Takuhisa Ootani

Masato Satou

Ryuji Iwamoto

Kouichi Ueki

Kazutaka Asano

Kenji Yasuda

Mitsunobu Enomoto

Kazuki Shiota

Hirozumi Nakamura

Kenji Nagatomo

Shigeru Murakami

Kazunori Ueyama

Takanori Kamimura

Akiyoshi Kawauchi

Omoto Yukihiro

Junichi Saitou

Gas meter includes shutoff valve, return unit, flow rate measurer, display, communication unit that communicates with an outside, controller, area information setting unit, and area information comparator. The gas meter compares, by area information comparator, a preset area information held in area information setting unit with a specified value of area information added to a remote shutoff instruction received by communication unit, and when the preset area information and the specified value of the added area information match, shutoff valve is closed.

Gas meter

Flow rate measurement is performed with a propagation time by using a pair of ultrasonic wave oscillators which is provided in flow path through which a fluid to be measured flows, and is disposed so as to transmit and receive an ultrasonic wave signal by causing the ultrasonic wave signal to be reflected on an inner wall of flow path at least once. In addition, adjustment of an amplification rate is periodically performed by amplifier, which amplifies the ultrasonic wave signal received by each of the ultrasonic wave oscillators to a predetermined amplitude, and a difference between a previous amplification rate and a current amplification rate is a predetermined value or more, and the instantaneous flow rate calculated by flow rate calculation unit is a predetermined flow rate or less, the reference voltage is adjusted by reference voltage setting unit. With the configuration, the propagation time can be stably measured and deterioration of the maximum amplitude is prevented.

Flow rate measurement device

A measurement control section of a flow meter device causes a measurement block dividing section to divide a sampling cycle Tc into three or more, for example, four measurement blocks Tb of an equal length and causes the flow measuring section to measure the flow of a fluid in each of the measurement blocks Tb. A flow calculating section of the flow measuring section calculates an average value of flow values obtained in all of the measurement blocks in each sampling cycle Tc, as a flow value in each sampling cycle Tc. This configuration allows a flow meter device which employs an inverse transit time difference method, such as an estimation gas meter, to more effectively lessen the influence of a pulsation and to perform flow measurement with higher accuracy.

Flow meter device

A setting method of a flow meter device comprises (A) measuring a compensation coefficient in a case where a fluid is flowed with a flow within a predetermined range, and deriving a first function representing as a linear function a relationship between a measurement compensation coefficient which is the measured compensation coefficient and a conversion value which is obtained by converting a set flow which is the flow of the flowed fluid, using a predetermined function; (B) setting a reference flow which is an arbitrary flow within the predetermined range and calculating a reference compensation coefficient which is a compensation coefficient corresponding to the reference flow based on the reference flow and the first function; and (C) storing the reference flow and the reference compensation coefficient corresponding to the reference flow.

Setting method of flow meter device and flow meter device

A flow meter device includes: a first vibrator, a second vibrator, a control unit, a timekeeper, and an arithmetic operation unit. The arithmetic operation unit is configured to: determine whether or not a time difference between a propagation time in the forward direction and a propagation time in the reverse direction is less than a predetermined value; calculate a propagation time correction amount based on the time difference if it is determined that the time difference is less than the predetermined value; and calculate a flow rate of the fluid by using the propagation time correction amount.

Ultrasonic flowmeter having an arithmetic operation unit for calculating propagation time correction value

A flow-rate measurement device includes a first transducer and a second transducer which are provided in a fluid flow path to transmit and receive an ultrasonic signal, a timer unit which measures a propagation time of the ultrasonic signal propagating between the first transducer and the second transducer, and a flow-rate calculation unit which executes a unit measurement step a predetermined number of times and calculates a flow rate of a fluid flowing in the fluid flow path on the basis of the propagation times measured the predetermined number of times, the unit measurement step being an operation in which a direction of transmission to reception between the first transducer and the second transducer is switched and the timer unit measures the propagation times of the ultrasonic signal in both directions. The flow-rate calculation unit measures a flow rate value of the fluid by a precise measurement step in which the unit measurement step is executed a plural number of times to calculate the flow-rate and an exploratory measurement step in which the unit measurement step is executed a smaller number of times than the number of executions in the precise measurement step to calculate the flow rate.

Flow-rate measurement device

A flow meter device of a fluid includes a time difference measuring means which measures time for a received wave to reach a zero cross point after the received wave exceeds a reference voltage, after transmission of a signal, and a reference voltage setting means which changes the reference voltage from a minimum value to a maximum value, recognizes peak voltages of waves of the received wave based on a plurality of inflection points at which a time difference measured by the time difference measuring means when the reference voltage is changed from the minimum voltage to the maximum voltage, is significantly changed, and automatically sets the reference voltage to a point between peak voltages of particular two waves based on a ratio between the peak voltages, and the reference voltage is changed from a voltage which is close to the peak voltages of the two waves and the peak voltages are newly recognized, when the reference voltage is newly set.

An object is to prevent a mistaken shutoff caused by the mistaken registration of an appliance of which an amount of gas used changes. An individual flow registration maintenance unit maintains a registered flow rate deleted due to an increase/decrease in flow rate, again, performs determination on the flow rate maintained when a new flow rate is registered or a flow rate added with the maintained flow rate, and in the case where it is regarded to be the same, re-register the maintained flow rate.

Gas shutoff device

It is an objective to appropriately assure a function of limiting use of appliances that cause changes in quantities of gas used. There are provided a flow detection unit; a flow computing unit; an average flow computing unit; a flow storage unitthat records an average flow quantity value; a flow change determination unitthat determines whether there is a flow change; a flow registration unitthat registers a flow quantity corresponding to a flow change or deletes a registered flow quantity close to the flow change when the flow change determination unithas determined an incremental or decremental change; a flow memory unit; a flow change correction memory unitthat, when the flow change determination unit has determined presence of a change and when only the maximum flow quantity is registered, determines whether or not a sum of registered flow quantities deleted in the past and an average flow fall within a predetermined range; a determination period unitthat, when no flow change is determined to have been for a predetermined time period, deletes flow quantities in the flow memory unit and the registered flow quantity, thereby performing re-registration; a monitoring value memory unit; an abnormality determination unitthat compares the flow quantity value in the flow registration unit with a determination value of the monitoring value memory unit, thereby determining presence or absence of an abnormality; and an operating time correction unitthat outputs a re-registration correction signal through use of a determination period unit.

Gas cutoff apparatus

To provide a flowmeter capable of enhancing metering resolution to thus effect accurate metering. When a fluid to be measured is supplied to or discharged from a metering chamber, a membraneprovided in the metering chamberis reciprocally actuated, and a rotation section Rperforms rotational movement in association with reciprocal movement of the membrane. At this time, since the rotation section Ris provided with a magnetor a direction sensor, the magnetor the direction sensoralso effects rotational movement. The direction sensordetects rotational movement, to thus determine a relative position between the membrane and the rotation section. Thus, the position of the membranecan be detected, and metering resolution is enhanced. Thus, accurate metering can be performed.

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Nara, Japan

Yasuo Koba