JP2013136461A - Vibrating flow device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibrating flow device in which when the frequency to be used for vibrating one or a plurality of conduits in a drive mode corresponds to the frequency to be used for vibrating a housing in one mode of a plurality of vibration modes peculiar to the housing, it becomes difficult to accurately measure characteristics of a flowing substance and therefore, the defect peculiar to the housing is eliminated.SOLUTION: A drive 104 vibrates one or the plurality of conduits 103A, 103B at one or a plurality of drive frequencies and a pick-off 105 measures the motions of the conduits 103A, 103B. The housing 200 encompasses at least part of at least one conduit. The plurality of vibration modes peculiar to the housing 200 are generated at the frequencies exceeding the one or the plurality of drive frequencies.

Description

  The present invention relates to an oscillating flow device having at least one housing in which multiple modes of vibration of the at least one housing occur at a frequency that exceeds the drive frequency used to vibrate the conduit. It is like that.

  Vibrating flow devices, such as densitometers and Coriolis flow meters, are used to measure flow material properties such as density, mass flow, volume flow, total mass flow, temperature, and other information. The oscillating flow device includes one or more conduits. The conduit can have a variety of shapes, for example, a straight shape, a U-shape, or a profile shape.

  The one or more conduits have a set of unique vibration modes including, for example, simple bending mode, torsion mode, radial mode and coupling mode. The one or more conduits have one of these modes (hereinafter referred to as “drive mode”) and a resonance frequency (hereinafter referred to as “drive frequency”) for the purpose of determining the characteristics of the flowing material. Therefore, it is vibrated by at least one drive. The one or more electronic devices transmit a sine wave drive signal to at least one drive. The drive is usually a magnet / coil combination, with the magnet secured to a conduit and the coil secured to a support structure or other conduit. The drive signal causes the drive to vibrate one or more conduits in drive mode and drive frequency. The drive signal is, for example, a periodic current transmitted to the coil.

  The at least one pickoff is configured to detect conduit motion and generate a sinusoidal pickoff signal representative of the oscillating conduit motion. This pickoff signal is transmitted to one or more electronic devices. According to well-known principles, the pick-off signal may be used by one or more electronic devices to determine the characteristics of the flow material, or if necessary, to adjust the drive signal. May be.

  An oscillating flow device typically includes a housing that encloses a driver, pickoff and conduit. The housing, for example, to provide a stable, known or controlled operating environment, i.e., an environment free of moisture and harmful gases, or via a driver or pick-off of the conduit by contact with so-called moisture, debris, other objects Commonly used for a variety of reasons, such as avoiding damage or damage during transportation.

  The housing has one or more inherent vibration modes including, for example, a simple bending mode, a torsion mode, a radial mode, and a lateral mode. In FIG. 4, for example, the bending mode is centered on the axis B, and the side surface mode is centered on the axis A. As shown in FIG. 5, it is not constant what frequency induces vibration of a certain mode. This frequency may vary depending on various factors including environmental conditions such as fluid density or temperature as shown in FIG. Vibration forces generated by the driver and from other sources of the material processing system, such as a pump, cause the housing to vibrate in one of a plurality of inherent vibration modes. If the frequency used to vibrate one or more conduits in drive mode corresponds to the frequency that causes the housing to vibrate in one of the housing's inherent vibration modes, the exact nature of the flow material It becomes difficult to perform measurement.

  The present invention is directed to overcoming this drawback inherent in conventional housings.

  The technical scope of the present invention is defined only by the appended claims, and is not affected to any extent by the content of the means for solving this problem.

  In one embodiment of the present invention, the vibratory flow device comprises at least one conduit, at least one drive, at least one pickoff, and at least one housing. The at least one drive causes the at least one conduit to vibrate at one or more drive frequencies, and the at least one pickoff is configured to measure movement of the at least one conduit. The at least one housing surrounds at least one drive, at least one pickoff, and a portion of at least one conduit. The plurality of modes of vibration of the at least one housing are configured to occur at a frequency that exceeds one or more drive frequencies.

  In another embodiment of the invention, the vibratory flow device comprises at least one conduit, at least one drive, at least one pickoff, and at least one housing. The at least one drive causes the at least one conduit to vibrate in a bending vibration mode having one or more drive frequencies, and the at least one pickoff is configured to measure movement of the at least one conduit. The at least one housing surrounds at least a portion of the at least one conduit. The plurality of modes of vibration of the at least one housing are adapted to occur at frequencies exceeding one or more drive frequencies. The at least one housing has a cross-sectional length extending along a direction generally parallel to the direction of bending mode motion and a cross-sectional width extending along a direction generally perpendicular to the direction of bending mode motion. The cross-sectional length dimension exceeds the cross-sectional width dimension.

  In yet another embodiment of the present invention, a method of fabricating an oscillating flow device includes providing at least one conduit, at least one drive, at least one pickoff, and at least one housing. The at least one drive is configured to vibrate at least one conduit at one or more drive frequencies, and the at least one pickoff is configured to measure movement of the at least one conduit. The at least one housing is configured to surround at least a portion of the at least one conduit. The at least one housing is configured such that the vibrations of the plurality of modes of the at least one housing occur at a frequency exceeding one or more drive frequencies.

In accordance with one aspect of the present invention, an oscillating flow device includes at least one conduit, at least one drive and at least one pickoff, and at least one drive, at least one pickoff and a portion of at least one conduit. And at least one drive configured to vibrate at least one conduit at one or more drive frequencies, and at least one pickoff configured to measure movement of the at least one conduit. The plurality of modes of vibration of the at least one housing are configured to occur at a frequency exceeding one or more drive frequencies.

  Preferably, the at least one drive is configured to vibrate at least one conduit in a bending vibration mode.

  Preferably, at least one housing has a generally U shape.

  Preferably, the at least one conduit vibrates in a bending vibration mode having one or more drive frequencies, and the at least one housing has a cross-sectional length extending along a direction generally parallel to the direction of bending mode motion; And a cross-sectional width extending along a direction generally perpendicular to the direction of motion of the bending mode, and the cross-sectional length dimension exceeds the cross-sectional width dimension.

  Preferably, a stiffening member is fixed to the at least one housing in order to increase the rigidity of the at least one housing.

  Preferably, the vibratory flow device is a Coriolis flow meter.

  Preferably, the vibratory flow device is a densitometer.

  In another aspect of the invention, the vibratory flow device includes at least one conduit, at least one drive and at least one pickoff, and at least one surrounding at least one drive, at least one pickoff and at least one conduit. And at least one drive configured to vibrate at least one conduit at one or more drive frequencies, and wherein at least one pickoff measures movement of the at least one conduit, The vibration of the plurality of modes occurs at a frequency exceeding one or more drive frequencies, and at least one housing has a cross-sectional length extending along a direction generally parallel to the direction of the bending mode motion, and the bending mode motion Almost straight to the direction And a cross-sectional width extending along a direction, such dimensions of the cross-section length is adapted to exceed the dimensions of the cross-sectional width.

  Preferably, the at least one housing is generally U-shaped.

  Preferably, the vibratory flow device is a Coriolis flow meter.

  Preferably, the vibratory flow device is a densitometer.

  According to another aspect of the invention, a method of making an oscillating flow device is configured to provide at least one conduit, at least one drive, and at least one pickoff, and surround at least a portion of the at least one conduit. Providing at least one housing, wherein the at least one drive is configured to vibrate at least one conduit at one or more drive frequencies, and the at least one pickoff causes movement of the at least one conduit. Constructed to measure, the at least one housing is configured such that multiple modes of vibration of the at least one housing occur at a frequency that exceeds one or more drive frequencies.

  Preferably, the at least one drive is configured to vibrate at least one conduit in a bending vibration mode.

  Preferably, the at least one housing is generally U-shaped.

  Preferably, the at least one drive is configured to vibrate at least one conduit in a bending vibration mode, and the at least one housing has a cross-sectional length extending along a direction generally parallel to the direction of motion of the bending mode; A cross-sectional width extending along a direction generally perpendicular to the direction of motion of the bending mode, and the cross-sectional length exceeds the cross-sectional width.

  Preferably, a stiffening member is fixed to at least one housing in order to increase the rigidity of the housing.

  Preferably, the vibratory flow device is a Coriolis flow meter.

  Preferably, the vibratory flow device is a densitometer.

It is a perspective view which shows the vibration type flow device which concerns on one Embodiment of this invention. It is a perspective view which shows the vibration type flow device provided with the housing of the disassembly state which concerns on one Embodiment of this invention. It is a perspective view which shows the vibration type flow device provided with the housing which concerns on one Embodiment of this invention. FIG. 4 is a cross-sectional view taken along line C of FIG. 3 showing a housing and a conduit according to an embodiment of the present invention. FIG. 6 is a graph illustrating the relationship between the frequency of inducing drive mode vibration in at least one conduit and the frequency of inducing multiple vibration modes in the housing and fluid density. FIG. 1 shows a typical conventional housing. FIG. 4 is a graph illustrating the relationship between the frequency of inducing drive mode vibration in at least one conduit and the frequency of inducing multiple vibration modes in the housing and fluid density in accordance with the present invention. It is a figure which shows the housing to which the stiffening member which raises the rigidity of a housing was attached.

  Illustrated in FIG. 1 is an exemplary vibratory flow device 5 in the form of a Coriolis flow meter having a sensor assembly 10 and one or more electronics 20. One or more electronic devices 20 are connected to the sensor assembly 10 via leads 100 to measure fluid material properties such as density, mass flow, volume flow, total mass flow, temperature and other information. And is also connected to the path 26.

  The sensor assembly 10 according to this embodiment includes a pair of flanges 101 and 101 ', manifolds 102 and 102', a driver 104, pick-offs 105 and 105 ', and conduits 103A and 103B. Manifolds 102 and 102 'are fixed to both ends of conduits 103A and 103B. Driver 104 and pickoffs 105, 105 'are connected to conduits 103A and 103B. The driver 104 is fixed to the conduits 103A and 103B at a position where the driver 104 can vibrate the conduits 103A and 103B in the drive mode. The two pickoffs are fixed correspondingly to the adjacent ends of the conduits 103A, 103B, respectively, to detect the movement of the conduits 103A, 103B. As will be apparent to those skilled in the art, any type of oscillating flow device, including, for example, a densitometer, may be used herein, regardless of the number of conduits, number of drivers, number of pickoffs, operating vibration modes or flow material desired characteristics Application of the technical idea described in the book is also included in the technical scope of the present invention.

  In this embodiment, the flanges 101 and 101 'are fixed to the manifolds 102 and 102'. Further, the manifolds 102 and 102 ′ of this embodiment are fixed to both ends of the spacer 106. The spacer 106 is adapted to maintain a spacing between the manifold 102 and the manifold 102 'of the present embodiment to avoid unnecessary vibration of the conduits 103A and 103B. When the sensor assembly 10 is inserted into a piping system (not shown) that carries the flow material, the flow material flows through the flange 101 into the sensor assembly 10, through the inlet manifold 102, where Thus, the entire amount of fluid material flows into the conduits 103A and 103B, flows through the conduits 103A and 103B, flows into the outlet manifold 102 ', and then flows out of the sensor assembly 10 from the flange 101'.

  In the present embodiment, the drive mode may be, for example, a first antiphase bending mode. Also, the conduits 103A, 103B are selected to have substantially the same mass distribution, moment of inertia, and elasticity module with respect to the bending axes X and X ′, respectively, and to the inlet manifold 102 and outlet manifold 102 ′. Installed properly. As shown, these conduits extend outwardly from the manifold in approximately parallel. Although the conduits 103A and 103B are generally illustrated as having a U shape, it is within the technical scope of the present invention that the conduits 103A and 103B have a linear shape or an irregular shape, for example. Furthermore, using a mode other than the anti-phase bending mode as the drive mode is also included in the technical scope of the present invention.

  In this embodiment where the drive mode may be the first anti-phase bending mode, these conduits 103A-103B are driven by the driver 104 in opposite directions about their respective bending axes X and X '. For example, driver 104 has one of many known configurations, such as a configuration in which a magnet is mounted on conduit 103A and an opposing coil is mounted on conduit 103B. An alternating current is passed through the opposing coils to vibrate both conduits 103A and 103B. Appropriate drive signals are applied to driver 104 through leads 110 by one or more electronic devices 20. In the present embodiment, it is described that the drive mode is a bending mode, but other drive modes are also included in the technical scope of the present invention.

  In this embodiment, one or more electronic devices 20 generate a drive signal, which is transmitted to the driver 104 through the lead 110, which causes the driver 104 to vibrate the conduits 103A and 103B. Yes. However, it is also within the technical scope of the present invention to generate a plurality of drive signals for a plurality of drivers. The one or more electronic devices 20 are adapted to calculate the properties of the flow material, such as mass flow, by processing the left and right velocity signals from the pickoffs 105, 105 '. The path 26 provides input means and output means for enabling one or a plurality of electronic devices 20 to communicate with an operator. Since it is not necessary to describe the circuit of one or more electronic devices 20 in order to understand the present invention, it will be omitted for the sake of brevity. The description of FIG. 1 is provided only as an example of a possible operation of one possible vibratory flow device and is not intended to limit the teaching of the present invention.

  2 and 3 show a housing 200 according to an embodiment of the present invention. According to one aspect of this embodiment, the housing 200 surrounds the conduits 103A, 103B, the driver 104, and the pickoffs 105, 105 '. As will be apparent to those skilled in the art, the housing wall 210 includes at least one pickoff, such as pickoffs 105, 105 ', and at least one driver, such as driver 104, leads 100, 110, 111, 111, which may be, for example, RTD wires. One or a plurality of openings for connecting to one or a plurality of electronic devices (not shown) are formed.

  As shown, the housing 200 is provided with a first end 201 and a second end 202. In the illustrated embodiment, the first end 201 is secured to a plate 303 that is secured to the manifold 102 on the inlet side of the vibratory flow device 5, and the second end 202 is a manifold 102 ′. It is being fixed to the plate 304 currently fixed to. As will be apparent to those skilled in the art, while one possible specific design of housing 200 has been described, there are a variety of methods that can be used to enclose conduits 103A, 103B. For example, as will be apparent to those skilled in the art, it is within the scope of the present invention to secure the housing 200 to other locations on the vibratory flow device 5 other than the plates 303, 304 in addition to the plates 303, 304 It is. Further, in the described embodiment, plate 303 and plate 304 are integrally provided on manifolds 102, 102 ', however, plates 303, 304 are secured to manifolds 102, 102 by welding or other methods. It may be. Furthermore, although a generally U-shaped housing 200 is illustrated, it is within the technical scope of the present invention that the housing is configured to have other shapes such as a linear shape or an irregular shape.

  Referring now to FIG. 4, a housing, such as a housing 200 of a vibratory flow device, such as vibratory flow device 5, is not limited to a lateral vibration mode about axis A and axis B. A plurality of vibration modes including a bending vibration mode. In the illustrated embodiment, axis B is generally parallel to axes X, X ′ (shown in FIG. 1) about which conduits 103A, 103B oscillate, and axis A is axis X, It is generally perpendicular to X ′ and B.

  Each vibration mode of the housing 200 is generated in a certain frequency range. Which mode is induced by what frequency is affected by a number of factors such as environmental factors such as fluid density, temperature, or an insulating wrap that can be disposed around the housing 200. FIG. 5 shows that in the housing described above, under certain conditions, several housing vibration modes occur at approximately the same frequency as the drive frequency that induces the drive mode in the conduits 103A, 103B. As further shown in FIG. 5, the housing is typically provided with one or more other modes that occur at a higher frequency than the drive frequency that induces the drive mode. If the frequency that induces a mode of vibration in the housing is approximately the same as the drive frequency that induces the drive mode, it is difficult to accurately measure the properties of the flow material.

  According to one aspect of this embodiment, the housing 200 according to this embodiment induces drive mode vibrations in the conduits 103A, 103B and a plurality of frequencies in the housing 200 that induce vibrations in multiple modes. The frequency separation is configured to exist between a plurality of drive frequencies. According to another aspect of this embodiment, the housing 200 has a drive mode vibration in the conduits 103A, 103B at frequencies that induce some mode of vibration in the housing 200 under corresponding operating conditions. Unlike the drive frequency that induces, it is configured not to cross. According to yet another aspect of this embodiment, the housing 200 has a frequency that induces several modes of vibration in the housing 200 that exceeds a drive frequency that induces drive mode vibrations in the conduits 103A, 103B. It is configured as follows.

  Referring now to FIG. 6, when a typical housing, such as housing 300, has a generally annular cross-sectional shape, and when the drive mode is a bending mode, the housing is in a bending mode of motion, i.e., It has a relatively small moment of inertia along a direction generally perpendicular to an axis such as axis B.

  However, in such a design, as shown in FIG. 5, the frequency that induces the bending mode in the housing may cross the drive frequency that induces the bending drive mode under certain conditions.

  The frequency that produces the mode of vibration in the housing is related to the moment of inertia of the housing. More specifically, the frequency at which a certain mode of vibration is generated can be modeled based on the following equation or a modification of the following equation.

この式において、
ｆｉ＝あるモードを生成する固有の周波数
Ｉ＝モードの方向に沿った慣性モーメント
Ｅ＝弾性係数
ρ＝材料密度
Ａ＝ビームの断面積
Ｉ＝モード数
λｉ＝固有値（Ｅｉｇｅｎｖａｌｕｅｓ）
上の式は片持ち梁の固有周波数をモデルとしているが、あるモードの振動を生成する固有周波数と慣性モーメントとの間に関係があることを示すことは有用である。さらに具体的にいえば、上の式から、慣性モーメントが大きくなるにつれて、いかなるモードの振動を誘発する周波数であってもその周波数は高くなることが分かる。したがって、本実施形態の１つの態様によれば、本発明の技術思想は、ハウジング２００の複数のモードの振動が一または複数のドライブ周波数を超える周波数で生じるように用いられてもよい。限定するわけではないが、例えば、曲げモードがドライブモードでありかつハウジングの曲げモードの周波数がある条件の下でドライブ周波数と交差する傾向がある本実施形態では、ハウジング２００がおおむね横長形状の断面を有するようになっている場合もある。さらに具体的にいえば、図４に示されているように、曲げモードがドライブモードである場合、ハウジング２００が、おおむね横長形状の断面を有し、幅Ｗを有し、この幅よりも大きい長さＬを有し、この長さＬが曲げモードの運動の方向に沿って延び、幅Ｗが曲げモードの方向に対しておおむね直角となっている。このようなアプローチに従えば、ハウジング２００の慣性モーメントが大きくなり、また図７に示されているように、ハウジング内に複数のモードの振動を誘発する周波数がドライブモードを誘発する周波数を超えるようになる。

In this formula:
fi = natural frequency for generating a certain mode I = moment of inertia along the direction of the mode E = modulus of elasticity ρ = material density A = cross-sectional area of the beam I = mode number λi = eigenvalues
Although the above equation is modeled on the natural frequency of a cantilever, it is useful to show that there is a relationship between the natural frequency that produces a mode of vibration and the moment of inertia. More specifically, from the above equation, it can be seen that as the moment of inertia increases, any frequency that induces vibrations in any mode increases. Thus, according to one aspect of this embodiment, the technical idea of the present invention may be used such that multiple modes of vibration of the housing 200 occur at frequencies exceeding one or more drive frequencies. For example, but not limited to, in this embodiment where the bending mode is drive mode and the frequency of the bending mode of the housing tends to intersect the drive frequency, the housing 200 is generally a cross-section with a horizontally long shape. There is also a case where it has come to have. More specifically, as shown in FIG. 4, when the bending mode is the drive mode, the housing 200 has a substantially horizontally-shaped cross section, has a width W, and is larger than this width. It has a length L that extends along the direction of motion of the bending mode, and the width W is generally perpendicular to the direction of the bending mode. According to such an approach, the moment of inertia of the housing 200 is increased, and as shown in FIG. 7, the frequency that induces the vibrations of the plurality of modes in the housing exceeds the frequency that induces the drive mode. become.

  In the above-described embodiment, problems tend to occur in the vibration of the bending mode of the housing, but what mode of vibration or vibrations tend to intersect the drive mode can be determined by, for example, the shape of the conduit, the housing Depends on several factors such as shape, individual drive mode, fluid density and temperature. Accordingly, what housing shapes can be used to avoid frequency crossings also varies within the scope of the present invention. For example, in the present embodiment, the housing 200 having a horizontally long shape is shown, but it is also within the technical scope of the present invention to use other configurations for avoiding frequency crossing. In one example, the wall 210 thickness or cross-sectional shape can be selected so that any mode frequency generated in the housing 200 exceeds the drive mode frequency generated under the corresponding operating conditions. It is. In yet another example, as shown in FIG. 8, if the torsion mode is a drive mode and the frequency that induces the torsion mode in the housing may tend to intersect the drive frequency, the stiffening member 400 may be It can be fixed to the housing 300 by welding. The stiffening member 400 may have any shape that provides rigidity to the housing 300, including but not limited to, for example, a laterally annular shape shown in FIG.

  This written description sets forth specific embodiments to teach those skilled in the art how to make or use the best mode of the invention. To teach the principles of the invention, some of the prior art has been simplified or omitted. As will be apparent to those skilled in the art, variations on these embodiments are also within the scope of the present invention.

  The detailed description of the above embodiments is not intended to be exhaustive of all embodiments that are considered by the inventors to be included within the scope of the present invention. More precisely, as will be apparent to those skilled in the art, some of the components of the above-described embodiments may be combined or removed in various ways to create further embodiments, and Further embodiments are within the scope and teachings of the present invention. Also, as will be apparent to those skilled in the art, the above-described embodiments may be combined in whole or in part to create further embodiments that fall within the scope of the technology and teachings of the present invention.

  While specific embodiments or examples of the invention have been described for purposes of illustration as described above, various modifications may be made within the scope of the invention as will be apparent to those skilled in the art. The teachings described herein may be applied to embodiments that differ from the embodiments described above and illustrated in the accompanying drawings. Accordingly, the scope of the invention is determined by the appended claims.

Claims (18)

At least one conduit (103A, 103B);
At least one drive (104);
At least one pick-off (105, 105 ');
And at least one drive (104), the at least one pickoff (105, 105 ′), and at least one housing (200) surrounding at least a portion of the at least one conduit (103A, 103B). ,
The at least one drive (104) vibrates the at least one conduit (103A, 103B) at one or more drive frequencies, and the at least one pickoff (105, 105 ′) causes movement of the at least one conduit. Configured to measure,
An oscillating flow device (5) configured to cause multiple modes of vibration of the at least one housing (200) to occur at a frequency exceeding the one or more drive frequencies.   The vibratory flow device (5) of claim 1, wherein the at least one drive (104) is configured to vibrate the at least one conduit (103A, 103B) in a bending vibration mode.   The vibratory flow device (5) of claim 1, wherein the at least one housing (200) has a generally U-shape.   The at least one conduit (103A, 103B) vibrates in a bending vibration mode having the one or more drive frequencies, and the at least one housing (200) is generally relative to the direction of motion of the bending mode. A cross-sectional length (L) extending along a parallel direction, and a cross-sectional width (W) extending along a direction generally perpendicular to the direction of motion of the bending mode. The oscillating flow device (5) according to claim 1, wherein the dimension of the cross-sectional width (W) exceeds the dimension of the cross-sectional width (W).   The vibratory flow device (5) according to claim 1, wherein a stiffening member (400) is fixed to the at least one housing (200) to increase the rigidity of the housing (200).   The vibratory flow device (5) according to claim 1, wherein the vibratory flow device (5) is a Coriolis flow meter.   The vibratory flow device (5) according to claim 1, wherein the vibratory flow device (5) is a densitometer. At least one conduit (103A, 103B);
At least one drive (104);
At least one pick-off (105, 105 ');
At least one housing (200) surrounding at least a portion of the at least one conduit (103A, 103B);
The at least one drive (104) vibrates the at least one conduit (103A, 103B) in a bending vibration mode having one or more drive frequencies, and the at least one pickoff (105, 105 ′) is the at least one Configured to measure the motion of one conduit,
A plurality of modes of vibration of the at least one housing (200) are configured to occur at a frequency exceeding the one or more drive frequencies;
The at least one housing (200) has a cross-sectional length (L) extending along a direction generally parallel to the direction of motion of the bending mode and a direction generally perpendicular to the direction of motion of the bending mode. An oscillating flow device (5) having a cross-sectional width (W) extending along a dimension of the cross-sectional length (L) exceeding a dimension of the cross-sectional width (W).   The vibratory flow device (5) of claim 8, wherein the at least one housing (200) has a generally U-shape.   The vibratory flow device (5) according to claim 8, wherein the vibratory flow device (5) is a Coriolis flow meter.   The vibratory flow device (5) according to claim 8, wherein the vibratory flow device (5) is a densitometer. Providing at least one conduit (103A, 103B), at least one drive (104) and at least one pickoff (105, 105 ′);
Providing at least one housing (200) configured to surround at least a portion of said at least one conduit (103A, 103B);
The at least one drive (104) is configured to vibrate the at least one conduit (103A, 103B) at one or more drive frequencies, and the at least one pickoff (105, 105 ′) is the at least one drive Configured to measure the movement of the conduit (103A, 103B);
Fabricating an oscillating flow device (5) in which the housing (200) is configured such that multiple modes of vibration of the at least one housing (200) occur at a frequency that exceeds the one or more drive frequencies. Method.   The method of making an oscillating flow device (5) according to claim 12, wherein the at least one drive (104) is configured to vibrate the at least one conduit (103A, 103B) in a bending vibration mode.   13. A method of making an oscillating flow device (5) according to claim 12, wherein the at least one housing (200) has a generally U-shape.   The at least one drive (104) is configured to vibrate the at least one conduit (103A, 103B) in a bending vibration mode, and the at least one housing (200) is in a direction of movement of the bending mode. A cross-sectional length (L) extending along a substantially parallel direction, and a cross-sectional width (W) extending along a direction generally perpendicular to the direction of motion of the bending mode, the cross-sectional length (L). The method of fabricating a vibratory flow device (5) according to claim 12, wherein the dimension of the cross-sectional width (W) exceeds the dimension of the cross-sectional width (W).   The vibratory flow device (5) according to claim 12, wherein a stiffening member (400) is fixed to the at least one housing (200) to increase the rigidity of the at least one housing (200). How to make.   13. A method of making an oscillating flow device (5) according to claim 12, wherein the oscillating flow device (5) is a Coriolis flow meter.   13. A method of making an oscillating flow device (5) according to claim 12, wherein the oscillating flow device (5) is a densitometer.

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