Abstract: In a flow meter device of the present invention, a time measuring section of the flow meter device includes a first counter which starts counting at a starting point of measurement of propagation time; and a second counter which starts counting at an end point of the measurement of the propagation time, and performs counting at a higher speed than the first counter. A propagation time TO is finally obtained by subtracting time ?t which is measured by the second counter and passes from the end point until the first counter counts up, from time T which is measured by the first counter and passes from a starting point until the first counter counts up after the end point. A flow calculating section calculates a flow with high accuracy using the propagation time TO. Thus, lower electric power consumption can be achieved, and accuracy of measurement of flow can be improved.

Abstract: A gas meter apparatus of the present invention comprises a flow measuring device which measures a gas flow; a measurement value calculating section and a liquid crystal display section which are configured to calculate an integrated value of the measured gas flow and electrically display the integrated value. Every time the measurement value calculating section determines that the integrated value has reached 1 liter, it informs a light emission commanding section of determination result. In response to this information, the light emission commanding section causes a LED light emitting section to emit light toward a sensor. Therefore, the gas meter apparatus is able to conduct a test by a test method in which a change in the displayed integrated value of the gas flow can be known from reflected light of emitted light, even when the integrated value of the gas flow is displayed in a digital form.

Abstract: In a flow meter device of the present invention, a control means causes a temperature measuring means to singly measure a temperature of a fluid. A flow compensation means calculates a temperature of a fluid from a propagation time and makes compensation for the flow rate using the temperature calculated based on the propagation time in a state in which the temperature is not measured by the temperature measuring means. Thus, when compensation is made for the measured flow rate to derive a flow rate at a desired temperature, flow rate compensation can be implemented with high accuracy, versatility of a target fluid can be improved, and low electric power consumption can be achieved.

Abstract: The ultrasonic flaw-rate measurement unit of the invention includes a flow measurement path inside which fluid to be measured flows through and to which a case accommodating a pair of ultrasonic transducers is installed, a pair of ultrasonic transducers disposed in the flow measurement path, a measuring circuit substrate incorporating a propagation time measuring part measuring a propagation time between the ultrasonic transducer transmitter and receiver and a flow-rate calculating part calculating a flow rate of the fluid to be measured based on the propagation time measured by the propagation time measuring part, and a damping material filling an interior space of the case and covering the pair of ultrasonic transducers.

Abstract: An ultrasonic flowmeter which can enhance measurement accuracy is provided, including ultrasonic transducers; a propagation time measurement block for measuring a propagation time elapsed before an ultrasonic wave transmitted from the ultrasonic transducer arrives at the ultrasonic transducer; a control block for determining a flow volume from the propagation time; correction calculation means for calculating a correction value based on characteristics of the ultrasonic transducers, a delay between transmission of an ultrasonic wave from the ultrasonic transducer and commencement of measurement of a propagation time, a delay between arrival of the ultrasonic wave at the receiving-side ultrasonic transducer and detection of the ultrasonic wave, and a difference between the measured and a true propagation times; and correction value selection means for selecting a correction value; and a propagation time correction block for correcting a propagation time.

Abstract: When a flow rate is equal to or more than a reference flow rate, a reference voltage is changed to a level capable of measuring stably to thereby realize the improvement of measurement accuracy at the time of a large amount of flow rate. A flow rate determination means compares a flow rate calculated by a flow rate calculation means with the reference flow rate. When the calculated flow rate is larger than the reference flow rate, the reference voltage set by a reference voltage setting means is changed, whereby the zero cross point can be detected stably at the portion where the degree of the influence of the change in the amplitude of the received signal is small. Thus, it is possible to provide a flow rate measuring device capable of measuring a flow rate stably with high accuracy even when a fluid flow is disturbed due to a large amount of flow rate.

Abstract: A device having a tube for heating or heat retaining of fluid includes a first path in which a connection section of a cord heater led out of the tube and a lead wire connected to a power supply is provided, a second path provided between the tube and the first path, and a drainage path for removing leaked fluid of the second path. In this device, the connection section is sandwiched by a pair of first sealing members to retain a sealed state and the cord heater passes through the second path in a sealed state by a second sealing member. This device can effectively prevent gas or liquid from leaking into the space where the connection section of a lead wire and a cord heater is provided.

Abstract: The present invention implements an ultrasonic flow meter device which does not require a complicated configuration such as a hermetic seal, in an inexpensive and easy manner. A typical ultrasonic flow meter device includes a fluid passage body, a measurement fluid passage placed within the fluid passage body, a pair of ultrasonic sensors, a wall defining the measurement fluid passage and attached with the ultrasonic sensors, a propagation time measuring means for measuring a propagation time of an ultrasonic sound wave propagating between the ultrasonic sensors, and a fluid flow calculating means for calculating a fluid flow based on a propagation time, and a seal member is provided between the fluid passage body and the wall to prevent a fluid from leaking.

Abstract: The present invention is directed to an ultrasonic flow rate measuring device capable of improving the measurement accuracy. Such an ultrasonic flow rate measuring device comprises first to third ultrasonic flow rate sensors in the measurement passage which are equipped with first ultrasonic wave transmitter-receivers and second ultrasonic wave transmitter-receivers. First to third ultrasonic wave propagation paths connecting the first ultrasonic wave transmitter-receiver and the second ultrasonic wave transmitter-receivers, respectively, intersect at different angles with the flow direction of fluid flowing through the measurement passages. The ultrasonic flow rate measuring device of the present invention obtains a flow rate measurement selectively from one of the first to third ultrasonic flow rate sensors in response to a flow rate Q.

Abstract: An ultrasonic flow rate measuring device according to the present invention improves a measuring accuracy. An ultrasonic flow rate measuring device includes an ultrasonic measuring portion in which a first ultrasonic transmitter-receiver and a second ultrasonic transmitter-receiver are provided to a measurement passage, and first to fifth partitioning plates are set substantially in parallel with an ultrasonic wave propagation path that connects the first ultrasonic transmitter-receiver and the second ultrasonic transmitter-receiver, whereby first to sixth flat passages are laminated/formed in the measurement passage by the partitioning plates. In this ultrasonic flow rate measuring device, the first ultrasonic transmitter-receiver and the second ultrasonic transmitter-receiver are arranged such that the ultrasonic measuring portion 20 measures the flow rate of the flat passage that is offset from the center along the lamination direction of the flat passages.

Abstract: An ultrasonic fluid measuring device capable of improving a measuring accuracy is provided. In an ultrasonic fluid measuring device 10, first to third ultrasonic measuring portions 16 to 18 are equipped with first ultrasonic transmitter-receivers 16A to 18A and second ultrasonic transmitter-receivers 16B to 18B provided to a measuring pass 14 respectively, and also first to third ultrasonic propagation paths 36 to 38 connecting the first ultrasonic transmitter-receiver 16A to 18A and the second ultrasonic transmitter-receivers 16B to 18B are provided to intersect with a passing direction of a fluid 24 flowing through the measuring pass 14 at different angles respectively. The ultrasonic fluid measuring device 10 employs any one of measured values of the first to third ultrasonic measuring portions 16 to 18 in response to a flow rate Q.

Abstract: An ultrasonic fluid measuring device capable of improving a measuring accuracy is provided. An ultrasonic fluid measuring device 10 includes an ultrasonic measuring portion 20 in which a first ultrasonic transmitter-receiver 21 and a second ultrasonic transmitter-receiver 22 are provided to a measuring pass 14, and first to fifth pass partition plates 25 to 29 that are set in substantially parallel with an ultrasonic propagation path 24 that connects the first ultrasonic transmitter-receiver 21 and the second ultrasonic transmitter-receiver 22, whereby first to sixth flat passes 32 to 37 are laminated/formed in the measuring pass 14 by the pass partition plates 25 to 29.

Abstract: A measurement control section includes a time measuring section for controlling an operation of measuring a travel time of an ultrasonic wave. The measurement control section operations, based on a high rate clock signal supplied from a ceramic oscillation circuit during the time measuring operation. A clock control section stops the high rate clock signal supplied from the ceramic oscillation circuit every time when the time measuring section completes its time measuring operation, and uses a low rate clock signal supplied from a quartz oscillation circuit to count a standby time between the end of measuring the travel time and the start of carrying out the next measuring operation.

Abstract: A device having a tube for heating or heat retaining of fluid includes a first path in which a connection section of a cord heater led out of the tube and a lead wire connected to a power supply is provided, a second path provided between the tube and the first path, and a drainage path for removing leaked fluid of the second path. In this device, the connection section is sandwiched by a pair of first sealing members to retain a sealed state and the cord heater passes through the second path in a sealed state by a second sealing member. This device can effectively prevent gas or liquid from leaking into the space where the connection section of a lead wire and a cord heater is provided.

Abstract: A measurement control section comprises a time measuring section for controlling an operation of measuring a travel time of an ultrasonic wave. The measurement control section operations, based on a high rate clock signal supplied from a ceramic oscillation circuit during the time measuring operation. A clock control section stops the high rate clock signal supplied from the ceramic oscillation circuit every time when the time measuring section completes its time measuring operation, and uses a low rate clock signal supplied from a quartz oscillation circuit to count a standby time between the end of measuring the travel time and the start of carrying out the next measuring operation.

Abstract: A heat-resistant plastic tube is mainly made of a polyester-based elastomer and exhibits a change amount in angle of ±10° or less in a shape retainability performance test, a change rate in inner diameter of ±2% or less in a dimensional stability performance test, a change rate in yield strength of ±30% or less in a flexibility retainability performance test. The heat-resistant plastic tube can be subjected to a thermal bending at a temperature in a use environment or higher and exhibits excellent retention of the bent shape through the thermal bending after being left in the use environment.

Abstract: An ultrasonic flowmeter includes a transmission/reception means provided in a flow path for performing transmission/reception using a state change of fluid; repetition means for repeating the transmission/reception; time measurement means for measuring a time of propagation repeated by the repetition means; flow rate detection means for detecting a flow rate based on a value of the time measurement means; and number-of-times change means for changing to a predetermined number of repetition times. With such a structure, an influence caused by a variation of a flow can be suppressed by changing the number of repetition times so as to be suitable for a variation. As a result, reliable flow rate measurement with a high accuracy can be achieved.

Abstract: In accordance with one embodiment, a flow meter of the present invention includes: transmission/reception means provided in a flow path for performing transmission/reception using a state change of fluid; repetition means for repeating the transmission/reception; time measurement means for measuring a time of propagation repeated by the repetition means; flow rate detection means for detecting a flow rate based on a value of the time measurement means; and number-of-times change means for changing to a predetermined number of repetition times. With such a structure, an influence caused by a variation of a flow can be suppressed by changing the number of repetition times so as to be suitable for a variation. As a result, reliable flow rate measurement with a high accuracy can be achieved.

Abstract: In accordance with one embodiment, a flow meter of the present invention includes: transmission/reception means provided in a flow path for performing transmission/reception using a state change of fluid; repetition means for repeating the transmission/reception; time measurement means for measuring a time of propagation repeated by the repetition means; flow rate detection means for detecting a flow rate based on a value of the time measurement means; and number-of-times change means for changing to a predetermined number of repetition times. With such a structure, an influence caused by a variation of a flow can be suppressed by changing the number of repetition times so as to be suitable for a variation. As a result, reliable flow rate measurement with a high accuracy can be achieved.

Abstract: For the purpose of solving the above problems, the present invention includes: transmission/reception means provided in a flow path for performing transmission/reception using a state change of fluid; repetition means for repeating the transmission/reception; time measurement means for measuring a time of propagation repeated by the repetition means; flow rate detection means for detecting a flow rate based on a value of the time measurement means; and number-of-times change means for changing to a predetermined number of repetition times. With such a structure, an influence caused by a variation of a flow can be suppressed by changing the number of repetition times so as to be suitable for a variation. As a result, reliable flow rate measurement with a high accuracy can be achieved.