JP2010256315A - Ultrasonic multiple reflection inhibition mechanism of ultrasonic wave gas/flow rate/gas concentration measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic multiple reflection inhibition mechanism with a partition formed on supersonic propagation paths of a pair of ultrasonic sensors for attenuating multiple reflection in using an ultrasonic measuring apparatus for measuring flow rates of all gases such as air and gas. <P>SOLUTION: The ultrasonic multiple reflection inhibition mechanism has a tube for passing gases such as air and gas, and includes a partition for preventing multiple reflection in consideration of gas interference with a flow path during reception and transmission for measurement of gas flowing from the exit by the pair of ultrasonic sensors. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultrasonic multiple reflection suppression mechanism of an ultrasonic measurement apparatus that suppresses multiple reflections of ultrasonic waves by an apparatus capable of measuring the flow rate of any gas such as air or gas by providing ultrasonic waves.

Conventionally, there is no partition mechanism provided on the ultrasonic propagation path of a set of ultrasonic sensors in the mechanism for suppressing multiple reflections of ultrasonic waves.

This has the following drawbacks.
Conventionally, in the case where no partition wall is provided, depending on the directivity angle of the ultrasonic wave, the ultrasonic wave transmitted from the ultrasonic element bounces off the structure in the middle and is reflected repeatedly to be a multiple reflected wave. If a reflected wave transmitted by itself is received, a necessary received signal wave and an unnecessary reflected wave are mixed, so that a necessary signal cannot be separated. Until now, it took time for the reflected wave to decay, and it was difficult to transmit signals one after another at a high frequency, making it difficult to achieve high resolution at low cost.
The present invention has been made to eliminate the above drawbacks.

A partition wall (2) is provided on the ultrasonic propagation path (4) of the pair of ultrasonic sensors (1) intersecting with the gas flow path in consideration of the hindrance of the gas flow path (3). The ultrasonic wave passes through the propagation path (4) and reaches the other sensor except for the useless reflection (5). Since the useless reflected wave so far does not reach the other and the transmitting sensor, switching from reception to transmission can be performed immediately.
The present invention is an ultrasonic multiple reflection suppression mechanism of an ultrasonic measurement device having the above-described configuration.

  By reducing and attenuating multiple reflections, even if the frequency of repeated transmission and reception is increased, it is less susceptible to multiple reflected waves, and measurement performance such as higher resolution can be improved.

  Since the partition wall (2) is provided on the ultrasonic wave propagation path, the ultrasonic signal reflected and returned can be limited. If there is no multiple reflection, each sensor will not receive the reflection of the signal that it issued, and the other party's signal can be received quickly, so the performance such as responsiveness and measurement resolution will be better.

Hereinafter, the best state for carrying out the present invention will be described.
Functions of a flow meter and a gas concentration meter having a structure in which an ultrasonic wave propagation path (4) of two ultrasonic sensors (1) installed opposite each other and a path (2) through which any gas to be measured flows intersect. In the ultrasonic wave propagation system path (4) used for the equipment having a gap between the two ultrasonic sensors (1) and the measurement flow path, taking into account the obstruction of the flow of the measurement gas, The obstacle (3) is provided.

  At this time, the space between the sensor and the bulkhead should be of a shape and size that allows the ultrasonic signals necessary for measurement to pass through the bulkhead, taking into account the resonance and resonance of the ultrasonic waves, such as by avoiding the opposing planes. Make one to several holes. As a result, the influence of unnecessary ultrasonic reflection and multiple reflection is reduced, and high performance is achieved.

  This structure can be applied not only to all gases but also to liquids and the like.

  It is a perspective view of this product.   It is a perspective view of this product.   It is a perspective view of this product.   It is the figure which looked at DTM1 of FIG. 1 from the front.   It is sectional drawing of TOP of FIG.   It is sectional drawing of RIGHT of FIG.   FIG. 2 is a cross-sectional view of TOP of FIG. 2 and represents the suppression of multiple reflection of ultrasonic waves by the partition walls of the unit.   It represents all gas flow paths and ultrasonic wave propagation paths.   It represents all gas flow paths and ultrasonic wave propagation paths.

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DESCRIPTION OF SYMBOLS 1 ... Ultrasonic sensor 2 ... Partition 3 ... All gas flow paths 4 ... Ultrasonic propagation path 5 ... Multiple reflection ultrasonic signal

Claims (2)

  In a machine that measures the gas flow rate and gas concentration using ultrasonic waves, when two ultrasonic sensors are arranged opposite to each other or in a V-shaped propagation path, and the ultrasonic propagation path and the measurement flow path intersect, Ultrasonic multiple reflection suppression mechanism that reduces the influence of unnecessary reflected waves and multiple reflected waves with a structure in which a partition with holes and slits for passing ultrasonic waves is provided on the propagation path.   Ultrasonic multiple reflection suppression that reduces the influence of multiple reflected waves by providing a partition on the ultrasonic propagation path with a position and shape that takes into account the obstruction of the flow path of the gas to be measured, such as air or gas, on the flow path mechanism.

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