JP5838292B2 - Ultrasonic flow measuring device - Google Patents

Description

  The present invention relates to an ultrasonic transducer that transmits and receives ultrasonic pulses and an ultrasonic flow rate measuring apparatus that measures the flow rate and flow velocity of gas and liquid using the ultrasonic transducer.

  Conventionally, in this type of ultrasonic flow measurement device, the flow measurement unit is configured with a plurality of blocked flow measurement paths, and the number of blocks in the flow measurement path is changed to correspond to the magnitude of the flow to be measured. (For example, refer to Patent Document 1).

  FIG. 8 shows a conventional ultrasonic flow rate measuring apparatus described in Patent Document 1. In FIG. As shown in FIG. 8, the flow rate measuring unit 15 is formed by a plurality of blocked flow rate measuring paths 15a, 15b, and 15c. In addition, attachment plates 16 and 17 are attached to the flow rate measurement unit 15, and corresponding to the flow rate measurement paths 15a, 15b, and 15c, and openings are opened.

  An upstream chamber 18 and a downstream chamber 19 are connected to the flow rate measurement unit 15. 20, an inlet 20 is connected to the upstream chamber 18, and a discharge unit is connected to the downstream chamber 19.

  By adopting such a configuration, the number of blocks of the flow rate measurement unit 15 is increased or decreased to cope with measurement of the flow rate. That is, when configuring a flow meter that measures a larger flow rate, the number of blocks of the flow rate measurement unit 15 is increased, and when configuring a flow meter that measures a smaller flow rate, the number of blocks is decreased. When the number of blocks increases or decreases, the mounting plates 16 and 17 having the number of openings corresponding to the number are used.

Japanese Patent No. 3692560

  However, in the conventional configuration, a detachable measurement channel and a pair of ultrasonic transducers are used. However, if the flow rate range is different, a block plate is also required by combining blocked channels. .

  In addition, because the flow paths are combined into blocks, the fluid to be measured will be disturbed due to the difference in the number of blocks, and the density distribution of the fluid to be measured will be disrupted and the ultrasonic waves will be uniformly distributed within the range where time measurement is performed with ultrasonic waves. The fact that a pair of ultrasonic transducers is arranged for each of the plurality of flow path measurement paths is handled to prevent transmission / reception, but each ultrasonic transducer needs to be switched, It is necessary to prepare a pair of ultrasonic transducers. In addition, it is necessary to set the connection and switching according to the number of measurement blocks, and changing the flow rate measurement unit is a very complicated task, and it has not been improved from the viewpoint of work efficiency in switching work corresponding to the flow rate change. There was room.

  The present invention has been made in view of the above-described problems of the prior art, and an ultrasonic flow rate measurement that can be easily performed using a low-cost member for switching the flow rate measurement unit to cope with the magnitude of the flow rate. An object is to provide an apparatus.

  In order to solve the above-described conventional problems, an ultrasonic flow rate measuring device according to the present invention includes a fluid supply unit into which a fluid to be measured flows, a fluid discharge unit from which the fluid to be measured is discharged, and between the fluid supply unit and the fluid discharge unit. Are connected to the measurement flow path section having a plurality of multi-layer flow paths whose flow path cross-section is divided by a rectifying member with respect to the flow direction of the fluid to be measured; Including a pair of ultrasonic transducers capable of transmitting and receiving and a flow path adjustment member that can be inserted for each multilayer flow path of the measurement flow path section, and changing the number of flow path adjustment members to be inserted into the multilayer flow path section The cross-sectional area of the measurement channel is adjusted by the above.

  This makes it possible to easily control the cross-sectional area of the measurement flow path section with a low-cost member, and the flow measurement performance of the ultrasonic flow measurement device can be easily performed in response to changes in the flow rate of the fluid to be measured. And it can be maintained at low cost.

  The ultrasonic flow rate measuring device of the present invention can maintain the flow rate measurement performance of the ultrasonic flow rate measuring device in a simple operation and at low cost in response to a change in the flow rate of the fluid to be measured.

Sectional drawing of the ultrasonic flow measuring device in Embodiment 1 of this invention Sectional drawing of the flow measurement part in Embodiment 1 of this invention Sectional drawing of the measurement flow-path part in Embodiment 1 of this invention. The side view of the fluid supply part provided with the flow-path adjustment member in Embodiment 1 of this invention. Sectional drawing of the measurement flow-path part in the state which inserted the flow-path adjustment member in Embodiment 1 of this invention. (A) is a top view of a fluid supply unit including two flow path adjustment members according to the second embodiment of the present invention, and (b) is an upper surface of a fluid supply unit including four flow path adjustment members. Figure The top view of the measurement flow path part of the state which inserted the baffle member unit in Embodiment 3 of this invention Sectional view of a conventional ultrasonic flow measurement device

  A first aspect of the present invention is a fluid supply part into which a fluid to be measured flows, a fluid discharge part from which the fluid to be measured is discharged, a fluid supply part connected to the fluid discharge part, and a flow direction of the fluid to be measured. And a pair of ultrasonic vibrations that are installed in the measurement flow path unit and can transmit and receive an ultrasonic signal. A measuring channel by changing the number of the channel adjusting members inserted into the multilayer channel part. It is an ultrasonic flow rate measuring device characterized by adjusting a cross-sectional area of a portion.

  This makes it possible to easily control the cross-sectional area of the measurement flow path section with a low-cost member, and the flow measurement performance of the ultrasonic flow measurement device can be easily performed in response to changes in the flow rate of the fluid to be measured. And it can be maintained at low cost.

  In a second aspect of the invention, particularly in the first aspect of the invention, the fluid supply section includes a guide section on the upstream side.

  Accordingly, high measurement accuracy can be maintained by smoothly introducing the fluid into the measurement flow path portion and suppressing the generation of turbulent flow.

In a third aspect of the invention, particularly in the first or second aspect of the invention, the flow path adjustment member is inserted to a region where ultrasonic waves transmitted / received from an ultrasonic transducer installed in the measurement flow path section propagate. The control unit includes a control unit that controls the transmission output of the ultrasonic transducer corresponding to the number of the channel adjustment members inserted into the measurement channel unit.

  As a result, since it has means for controlling the transmission output of the ultrasonic transducer corresponding to the cross-sectional area of the measurement flow path section, a highly accurate flow rate with ultrasonic transmission / reception pulses of a pair of ultrasonic transducers Measurement is possible.

  Hereinafter, an ultrasonic flow measuring device according to an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing a configuration of an ultrasonic flow measuring device according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view showing a configuration of a flow measuring unit of the ultrasonic flow measuring device, and FIG. It is sectional drawing of the measurement flow path of a flow-path measurement part.

  As shown in FIG. 1, the ultrasonic flow rate measuring device 1 includes a case body 2 having a fluid inlet 3 for introducing a fluid to be measured and a fluid outlet 4 for discharging the fluid to be measured. 2 includes a pair of ultrasonic transducers 5 and 6 and a control unit (not shown) that measures the ultrasonic transmission time of the pair of ultrasonic transducers and calculates the flow velocity of the fluid to be measured. A flow rate measuring unit 7 is accommodated.

  As shown in FIG. 2, the flow rate measurement unit 7 includes a fluid supply unit 8 that is an inlet through which a fluid such as a gas flows as indicated by an arrow A, and a measurement channel unit 9 that is connected to the downstream side of the fluid supply unit 8. And a fluid discharge unit 10 connected to the downstream side of the measurement flow path unit 9. The measurement flow path unit 9 includes a pair of ultrasonic transducers 5 and 6 and ultrasonic transducers 5 and 6. A control unit (not shown) that performs transmission / reception and flow rate calculation is installed. The fluid supply unit 8 has a frame shape having an opening through which a fluid can pass at the center, and is configured to be detachable from the measurement channel unit 9.

  The function of the flow rate measurement unit 7 is that the ultrasonic wave oscillated from the ultrasonic transducer 5 is reflected by the lower wall surface of the measurement flow path unit 9 and received by the ultrasonic transducer 6. It is also transmitted and received from the opposite ultrasonic propagation. Thus, the fluid flow velocity is calculated from the propagation time of the ultrasonic waves.

  When this flow velocity is V and the cross-sectional area of the flow path of the flow rate measuring unit 7 is S, the flow rate Q is calculated by the following equation.

Q = K ・ V ・ S
K is a correction coefficient for converting the measured flow velocity V into an average flow velocity.

  As shown in FIG. 3, the measurement flow path portion 9 is provided with a rectifying member 11 that partitions the cross section of the flow path in a substantially vertical direction, and a plurality of multilayer flow paths 12 are formed. The fluid flowing through the measurement flow path portion 9 by the multilayer flow path 12 passes through the measurement flow path portion 9 in a rectified state. The fluid that has passed through the measurement flow path section 9 passes through the fluid discharge section 10 and is sent out of the apparatus through the fluid discharge port 4 of the ultrasonic flow rate measuring apparatus 1.

The number of the multilayer flow paths 12 in the measurement flow path section 9 is determined by the rectifying member 11 installed in advance according to the amount of fluid flowing. Therefore, for example, when used for flow rate measurement as a gas meter, when the number of gas equipment to be used changes and only a small amount of gas flow flows, the number of multi-layer channels 12 determined in advance is different from each other. The flow rate flowing every 12 is not uniform, and there is a possibility that the ultrasonic propagation time for each multi-layer flow path 12 may be different if only a pair of ultrasonic transducers 5 and 6 is used, and high-precision flow rate measurement may not be possible. It is necessary to switch to the flow rate measuring unit 7 having the multilayer flow path 12 corresponding to the number switching.

  In the ultrasonic flow rate measuring apparatus 1 according to the present embodiment, for example, the fluid supply unit 8 that integrally includes the flow path adjusting member 13 for filling a part of the multilayer flow path 12 when the number becomes small. The flow path adjusting member 13 is inserted in the multilayer flow path 12 in advance and the cross-sectional area of the multilayer flow path 12 can be adjusted.

  As shown in FIG. 2, the flow path adjustment member 13 has a length that covers the substantially entire length of the measurement flow path section 9 in a state of being inserted into the measurement flow path section 9, and the ultrasonic transducers 5, 6. It is set so as to cover the entire region where the ultrasonic wave transmitted / received from is propagated.

  FIG. 4 is a side view of the fluid supply unit 8 integrally provided with the flow path adjusting member 13, and FIG. 5 is a cross-sectional view of the measurement flow path unit 9 with the flow path adjusting member inserted.

  As shown in FIG. 4, the fluid supply unit 8 provided with the flow path adjusting member 13 includes an attachment / detachment mechanism that can be fixed to the measurement flow path unit 9 with a hook 8 a or the like, so that it can be easily replaced. Yes.

  In addition, as shown in FIG. 5, in the state where the flow path adjustment member 13 is inserted into the measurement flow path portion 9, a part of the plurality of multilayer flow paths 12 is blocked, and the cross-sectional area of the measurement flow path section 9 is It is getting smaller.

  In this way, by switching the number of the multi-layer flow paths 12 through which the fluid passes by the flow path adjusting member 13 formed integrally with the fluid supply section 8 in the multi-layer flow path 12 of the measurement flow path section 9 for measuring the flow rate. The flow passage cross-sectional area of the measurement flow passage section 9 can be controlled. For example, it is possible to cope with a change in the basic flow rate of the fluid to be measured by switching the number of the gas appliance. There is no need to replace the entire measuring section 7 or the entire measuring flow path section 9.

  In addition, the ultrasonic flow measuring device of the present embodiment can easily control the cross-sectional area of the measurement flow path portion with a low-cost member, and the ultrasonic flow rate corresponding to the change in the flow rate of the fluid to be measured. The flow rate measurement performance of the measuring device can be maintained with simple work and at low cost.

  In this embodiment, the number of flow path adjustment members 13 provided in the fluid supply unit 8 is two. However, the number of flow path adjustment members 13 is not limited to this. The number can be changed arbitrarily.

(Embodiment 2)
FIG. 5 shows the fluid supply unit 8 integrally including the flow path adjusting member 13 according to Embodiment 2 of the present invention, and FIG. 6A integrally includes two flow path adjusting members 13. FIG. 6B is a top view of the fluid supply unit 8 including the four flow path adjusting members 13.

  The present embodiment is different from the first embodiment in that a guide portion is integrally formed on the upstream side of the fluid supply portion 8.

  As shown in FIG. 6A, the fluid supply unit 8 includes two flow path adjusting members 13 on the downstream side, and integrally includes a guide portion 8b formed at least partially in a curved surface on the upstream side. ing. The guide portion 8b is formed in such a shape that the fluid does not directly contact the front end of the flow path adjustment member 13 and smoothly flows into the multilayer flow path 12 in which the flow path adjustment member 13 is not inserted.

  By providing the guide portion 8b, high measurement accuracy can be maintained by smoothly introducing the fluid into the measurement flow path portion 9 and suppressing the generation of turbulent flow.

  As shown in FIG. 6B, when four flow path adjusting members 13 are provided, the introduction of fluid can be made smoother by making the shape of the guide portion 8b in accordance with the number of the flow guide members 8b. It is.

  In the present embodiment, the flow path adjusting member 13 included in the fluid supply unit 8 is configured to be inserted into the multilayer flow path 12 at an even number, but this is not a limitation, and the flow rate flowing through the measurement flow path unit 9 Thus, the number of inserted flow path adjusting members 13 can be arbitrarily changed.

(Embodiment 3)
FIG. 7 is a cross-sectional view of the measurement flow path portion of the ultrasonic flow measurement device according to the second embodiment of the present invention as viewed from above.

  The ultrasonic waves oscillated from the ultrasonic transducers 5 and 6 are received by the ultrasonic transducers 6 and 5 on the receiving side through the propagation path of the ultrasonic oscillation / vibration region 14 shown in the figure. A plurality of multilayer flow paths 12 a, 12 b, 12 c, 12 d, and 12 e in the measurement flow path section 9 partitioned by the rectifying member 11 are multilayered by the flow path adjustment member 13 that is formed integrally with the fluid supply section 8. The flow paths 12a and 12e are filled. At that time, the flow path adjusting member 13 blocks some ultrasonic propagation paths emitted from the ultrasonic transducers 5 and 6, and the ultrasonic transmission intensity becomes weak.

  For this reason, when the flow path adjusting member 13 blocks a part of the multilayer flow path 12, the output of the ultrasonic vibrators 5, 6 is increased to increase the supersonic wave of the ultrasonic vibrators 5, 6. It is necessary to increase the sound transmission intensity and maintain the flow measurement accuracy.

  When a part of the multilayer flow path 12 in the measurement flow path section 9 is blocked, information on the insertion of the flow path adjustment member 13 is input to the control section, and the output of the ultrasonic transducers 5 and 6 is increased. The ultrasonic flow measurement performance similar to that when the flow path adjusting member 13 is not inserted can be maintained, and a highly versatile ultrasonic flow measurement device can be provided.

  Regarding the method of setting the output values of the ultrasonic transducers 5 and 6, the output value information of the ultrasonic transducer corresponding to the cross-sectional area of the multilayer flow channel 12 when the flow channel adjusting member 13 is inserted into the multilayer flow channel 12. Any means may be used, such as determining the output value by calculating the flow rate after measuring the flow velocity of the fluid for a certain period of time after inserting the flow path adjusting member 13.

  As described above, the ultrasonic flow measurement device according to the present invention improves the versatility of the measurement device that measures the flow rate of the fluid flowing in the measurement flow path, and is therefore suitable for application to a flow measurement reference device and a gas meter. .

DESCRIPTION OF SYMBOLS 1 Ultrasonic flow measuring device 5, 6 Ultrasonic vibrator 8 Fluid supply part 8b Guide part 9 Measurement flow path part 10 Fluid discharge part 11 Rectification member 12 Multilayer flow path 13 Flow path adjustment member

Claims (1)

A fluid supply section into which the fluid to be measured flows;
A fluid discharge part from which the fluid to be measured is discharged;
A measurement flow path section that is connected between the fluid supply section and the fluid discharge section, and includes a plurality of multilayer flow paths whose flow path cross-section is divided via a rectifying member with respect to the flow direction of the fluid to be measured;
A pair of ultrasonic transducers installed in the measurement channel and capable of transmitting and receiving ultrasonic signals;
A flow path adjustment member that can be inserted for each of the multilayer flow paths of the measurement flow path section,
Adjusting the cross-sectional area of the measurement flow path portion by changing the number of flow path adjustment members inserted into the multilayer flow path portion;
The flow path adjustment member is configured to be inserted to a region where ultrasonic waves transmitted / received from an ultrasonic transducer installed in the measurement flow path portion propagate,
Corresponding to the number of the flow path adjustment members inserted into the measurement flow path section, a control section for controlling the transmission output of the ultrasonic transducer,
An ultrasonic flow rate measuring device.