Flow tube bumper for vibrating fluid meter

Abstract

According to one embodiment, a transducer assembly 200 for a vibrometer 5 having meter electronics 20 is provided. The transducer assembly 200 includes a coil portion 204A that includes a coil bobbin 220 and a coil 222 wound around the coil bobbin 220. The magnet portion 204B includes a magnet. The coil portion 204A and the magnet portion 204B are constrained from movement in both the x-axis and the y-axis to prevent the coil portion 204A from colliding with the magnet portion 204B.

Description

Technical Field

[0001] The embodiments described below relate to vibration meters, and more particularly, to flow tube bumpers for vibratory flow meters.

Background Art

[0002] Vibration meters such as vibratory density meters and Coriolis flow meters are generally known and are used to measure the mass flow rate of materials in a conduit and other information. The material may be flowing or stationary. Representative Coriolis flow meters are all disclosed in U.S. Patent Nos. 4,109,524, 4,491,025, and 31,450 by J.E. Smith et al. These flow meters have one or more conduits in a straight or curved configuration. Each conduit configuration in a Coriolis mass flow meter has a set of natural vibration modes, which can be simple bending, torsion, or combined types. Each conduit can be driven to vibrate in a preferred mode.

[0003] The material flows into the flow meter from a connected pipeline on the inlet side of the flow meter, is guided through the conduit, and is discharged from the flow meter through the outlet side of the flow meter. The natural vibration modes of the vibrating material filling system are partially defined by the combined mass of the conduit and the material flowing through the conduit.

[0004] When there is no flow through the flowmeter, the driving force applied to the conduit causes all points along the conduit to vibrate with the same phase, or with a small "zero offset," which is a time delay measured at zero flow rate. When material begins to flow through the flowmeter, the Coriolis force causes each point along the conduit to have a different phase. For example, the phase at the inlet end of the flowmeter lags behind the phase at the central driver position, while the phase at the outlet leads the phase at the central driver position. Pick-off sensors on the conduit generate sinusoidal signals that represent the movement of the conduit. The signals output from the pick-off sensors are processed to determine the time delay between the pick-off sensors. The time delay between two or more pick-off sensors is proportional to the mass flow rate of the material flowing through the conduit.

[0005] The meter electronics connected to the driver generate a drive signal to operate the driver and determine the mass flow rate and other material properties from the signal received from the pick-off sensor. While the driver can have one of many well-known configurations, the magnet and opposing drive coil configuration has achieved great success in the vibration meter industry. Examples of suitable drive coil and magnet configurations are described in U.S. Patents 7,287,438 and 7,628,083, both of which are delegated to Micro Motion, Inc. and incorporated herein by reference. An alternating current flows through the drive coil, causing the conduit to vibrate at a desired flow amplitude and frequency. It is also known in the art that pick-off sensors can be provided with a magnet and coil configuration very similar to the driver configuration. However, while the driver receives current to induce motion, the pick-off sensor can use the motion provided by the driver to induce a voltage. This voltage is proportional to the displacement of the conduit. The magnitude of the time delay measured by the pick-off sensor is very small, often measured in nanoseconds. Therefore, the transducer output needs to be very precise.

[0006] Figure 1 shows an example of a conventional vibrometer 5 having the configuration of a Coriolis flowmeter comprising a sensor assembly 10 and meter electronic equipment 20. The meter electronic equipment 20 electrically communicates with the sensor assembly 10 to measure properties of the flowing material, such as density, mass flow rate, volumetric flow rate, integrated mass flow rate, temperature, and other information.

[0007] The sensor assembly 10 includes a pair of flanges 101 and 101', manifolds 102 and 102', and conduits 103A and 103B. Manifolds 102 and 102' are attached to the opposing ends of conduits 103A and 103B. The flanges 101 and 101' of a conventional Coriolis flow meter are attached to both ends of a spacer 106. The spacer 106 maintains the spacing between manifolds 102 and 102' and prevents undesirable vibrations within conduits 103A and 103B. Conduits 103A and 103B extend outward from the manifolds substantially parallel to each other. When the sensor assembly 10 is inserted into a pipeline system (not shown) that carries a flowing material, the material enters the sensor assembly 10 through the flange 101, passes through the inlet manifold 102, where the entire volume of material is guided into conduits 103A and 103B, flows through conduits 103A and 103B, returns to the outlet manifold 102', and exits the sensor assembly 10 through the flange 101'.

[0008] A conventional sensor assembly 10 includes a driver 104. The driver 104 is fixed to conduits 103A and 103B in a position that allows the driver 104 to vibrate conduits 103A and 103B in a driving mode. More specifically, the driver 104 includes a first driver component 104A attached to conduit 103A and a second driver component 104B attached to conduit 103B. The driver 104 may comprise one of many well-known configurations, such as a coil attached to conduit 103A and opposing magnets attached to conduit 103B.

[0009] In this example of a prior art Coriolis flowmeter, the driving mode is the first phase-out bending mode, and conduits 103A and 103B are selected to provide an equilibrium system having substantially the same mass distribution, moment of inertia, and modulus of elasticity with respect to the bending axes WW and W'-W', respectively, and are appropriately mounted to the inlet manifold 102 and outlet manifold 102'. In this example where the driving mode is the first phase-out bending mode, conduits 103A and 103B are driven by the driver 104 in opposite directions about their respective bending axes WW and W'-W'. A driving signal in the form of an alternating current is provided by the meter electronics 20, for example, via path 110, which passes through a coil and can cause both conduits 103A and 103B to vibrate. Those skilled in the art will understand that other driving modes may be used in conventional Coriolis flowmeters.

[0010] The illustrated sensor assembly 10 includes a pair of pickoffs 105, 105' attached to conduits 103A, 103B. More specifically, the first pickoff elements 105A and 105'A are positioned on the first conduit 103A, and the second pickoff elements 105B and 105'B are positioned on the second conduit 103B. In the illustrated example, the pickoffs 105, 105' may be electromagnetic detectors, such as pickoff magnets and pickoff coils, which generate pickoff signals representing the velocity and position of conduits 103A, 103B. For example, the pickoffs 105, 105' can supply pickoff signals to meter electronic equipment 20 via paths 111, 111'. Those skilled in the art will understand that the movement of conduits 103A, 103B is generally proportional to certain properties of the flowing material, such as the mass flow rate and density of the material flowing through conduits 103A, 103B. However, the movement of conduits 103A and 103B also includes zero-flow delay or offset, which may be measured at pickoffs 105 and 105'. Zero-flow offset can be caused by a variety of factors, such as non-proportional damping, residual flexibility response, electromagnetic crosstalk, or phase delay in the instrument.

[0011] Conventional sensor assemblies 103, 104, and 105 are aligned on the coil axis to minimize the air gap in the magnetic circuit and maximize the coupling between the magnetic field and the coil field. Generally, the retainer assembly is mounted on the first conduit, while the coil assembly is mounted on the second conduit (the arrangement differs in single-conduit instruments). The retainer and coil must be mounted carefully to maximize the clearance between elements.

[0012] Unfortunately, under certain conditions, the coil and retainer assembly may come into contact, potentially damaging and rendering the flow meter inoperable. For example, manufacturing variations can lead to axial misalignment. In another scenario, if the fluid slug flowing through one conduit travels a longer distance than the fluid flowing through the other conduit, inertial forces and relative lateral motion can occur between the conduits, resulting in magnet / coil / retainer contact and damage to the assembly. In yet another example, temperature differences can lead to contact between the coil and retainer assembly. A hotter fluid flowing through one conduit at a significantly earlier time than the fluid flowing through the other conduit can cause uneven conduit expansion, exceeding the coil / retainer clearance limit and resulting in contact.

[0013] Therefore, as can be understood, conventional transducer assemblies can be susceptible to misalignment damage under various conditions that may be encountered during normal instrument operation. In the art, there is a need for transducer assembly sensors that do not suffer unintended contact and resulting damage. The embodiments described below overcome these and other problems, achieving advances in the art. [Overview of the project]

[0014] A transducer assembly for a vibration meter having meter electronic equipment is provided according to one embodiment. The transducer assembly comprises a coil section comprising a coil bobbin and a coil wound around the coil bobbin. The magnet section comprises a magnet. The coil section and the magnet section are restricted from moving in both the x and y directions so as to prevent the coil section from colliding with the magnet section.

[0015] A flow meter according to one embodiment is provided. This flow meter comprises a meter electronic device, a first conduit, a second conduit, and a magnet section having a magnet, the magnet section being attached to the first conduit. A coil section comprises a coil bobbin and a coil wound around the coil bobbin, the coil section being attached to the second conduit. Physical stoppers are attached to the first conduit and the second conduit, respectively, and the physical stoppers are configured to contact each other to restrict the movement of the conduits, thereby preventing the coil section and the magnet section from colliding with each other.

[0016] A method is provided for forming a vibration meter, which includes a sensor assembly having one or more conduits, according to one embodiment. The method includes the steps of fixing a coil portion to a conduit and fixing a magnet portion to another conduit, wherein the coil portion and the magnet portion are restricted so that the coil portion does not collide with the magnet portion.

[0017] [Pattern] According to one embodiment, a transducer assembly for a vibration meter having meter electronic equipment comprises a coil section comprising a coil bobbin and a coil wound around the coil bobbin. The magnet section comprises a magnet. The coil section and the magnet section are restricted from moving in both the x and y directions so as to prevent the coil section from colliding with the magnet section.

[0018] Preferably, the retaining bracket assembly comprises a first bracket attached to a conduit, with the magnet portion attached to the first bracket. A second bracket is attached to another conduit, with the coil portion attached to the second bracket. A limiting element extends from the first bracket into the space within the second bracket, and the contact between this limiting element and the wall of the space determines the limit of movement between the first and second brackets.

[0019] Preferably, the restricting body occupies the space concentrically with respect to the walls of the space.

[0020] Preferably, the transducer assembly includes a second restrictor extending from a second bracket to a space within the first bracket, the contact between the second restrictor and the wall of the space determining a second movement restrictor between the first bracket and the second bracket.

[0021] Preferably, at least one weight is provided on at least one of the first bracket and the second bracket to maintain the mass balance between the conduits and the moment of inertia about the central vertical axis.

[0022] According to one embodiment, the flow meter comprises a meter electronic device, a first conduit, a second conduit, and a magnet section, the magnet section being attached to the first conduit. The coil section comprises a coil bobbin and a coil wound on the coil bobbin, the coil section being attached to the second conduit. Physical stoppers are attached to the first and second conduits respectively, and the physical stoppers are configured to contact each other to restrict the movement of the conduits, thereby preventing the coil section and the magnet section from colliding with each other.

[0023] Preferably, the physical stopper includes first and second plates, each plate including teeth formed on one side of the plate and slots formed on the opposite side of the plate. When the teeth are arranged in the slots in a clearance fit, an interleaved fork region is formed, the width of each tooth is smaller than the width of each slot, and the clearance between the tooth and the slot determines the allowable movement amount of the conduits (103A, 103B) in the X-axis direction of the flowmeter until contact occurs between the tooth and the slot, and the clearance is configured to be smaller than the distance between the coil portion and the magnet portion of the transducer assembly.

[0024] Preferably, the physical stopper includes a plurality of bars, each conduit includes a bar, and the bars are configured to be nested with each other. The restricting body is inserted into an opening provided at the end of at least one nested bar.

[0025] Preferably, the opening is provided at the end of the nested bar, and the restricting body is disposed within the opening. The distance that the restricting body protrudes into the space determines the movement amount in the X-axis that the conduit can move until the nested bar collides and prevents further movement.

[0026] Preferably, the restricting body is threaded and the opening includes mating threads.

[0027] Preferably, the restricting body is fixed in a predetermined position.

[0028] According to one aspect, a method of forming a vibrator including a sensor assembly having one or more conduits includes fixing a coil portion to a conduit and fixing a magnet portion to another conduit, the coil portion and the magnet portion being constrained so that the coil portion does not collide with the magnet portion.

[0029] Preferably, the coil portion and the magnet portion are restricted from moving in both the x-axis and y-axis directions.

[0030] Preferably, the method further comprises the steps of: attaching a first bracket to a conduit, wherein the magnet portion is attached to the first bracket; attaching a second bracket to a conduit, wherein the coil portion is attached to the second bracket; and extending a restricting body from the first bracket to the space within the second bracket, wherein the contact between the restricting body and the wall of the space determines the restriction of movement between the first bracket and the second bracket.

[0031] Preferably, the coil and magnet sections are restricted from moving in the x-axis direction by a physical stopper.

[0032] Preferably, the physical stopper comprises multiple bars, each conduit comprises a bar, and the bars are configured to nest around each other. The restrictor is inserted into an opening provided at the end of at least one nested bar, and the distance the restrictor protrudes into the space between the nested bars determines the amount of X-axis movement the conduit can make before the nested bars collide and further movement is prevented.

[0033] Preferably, the physical stopper comprises first and second plates. Tines are formed on one side of the plates. Slots are formed on the opposite side of the plates. The tines are positioned in the slots with clearance fitting to form nested fork regions, the width of each tine being smaller than the width of each slot, and the gap between the tines and slots determines the allowable amount of conduit movement in the X-axis direction of the flowmeter before contact between the tines and slots occurs, and the gap is configured to be smaller than the distance between the coil and magnet portions of the transducer assembly. [Brief explanation of the drawing]

[0034] [Figure 1] Figure 1 shows a flow meter. [Figure 2] Figure 2 shows a cross-sectional view of a conventional transducer assembly. [Figure 3]Figure 3 shows one embodiment of a physical stopper for a flow meter. [Figure 4] Figure 4 shows an alternative diagram of the physical stopper in Figure 3. [Figure 5] Figure 5 shows an embodiment of a physical stopper for another flow meter. [Figure 6] Figure 6 shows an alternative diagram of the physical stopper in Figure 5. [Figure 7] Figure 7 shows an improved coil and retaining bracket assembly according to one embodiment. [Figure 8] Figure 8 shows an alternative diagram of the coil and retaining bracket assembly shown in Figure 7. [Modes for carrying out the invention]

[0035] Figures 3–7 and the following description illustrate specific examples to teach those skilled in the art how to construct and use the best mode of the transducer embodiment. Some conventional embodiments have been simplified or omitted for the purpose of teaching the principles of the present invention. Those skilled in the art will understand the variations from these embodiments that fall within the scope of this specification. Those skilled in the art will understand that multiple variations of the flow meter can be formed by combining the features described below in various ways. As a result, the embodiments described below are not limited to the specific examples described below, but are limited only by the claims and their equivalents.

[0036] Figure 2 shows a cross-sectional view of a prior art transducer assembly 200. The transducer assembly 200 can be coupled to first and second flow conduits 103A and 103B. The prior art transducer assembly 200 comprises a coil section 204A and a magnet section 204B. The magnet section 204B includes a magnet 211. The magnet 211 may be housed in a magnet holder 213 that helps direct the magnetic field. The magnet section 204B may also include a magnetic pole piece 215. The magnet section 204B may include a typical magnet section of a prior art sensor component. The magnet section 204B can be coupled to the second flow conduit 103B with a mounting bracket (not shown for clarity). The mounting bracket can be coupled to the flow conduit 103B according to well-known techniques such as welding, brazing, or bonding.

[0037] The coil section 204A can be connected to the first flow conduit 103A by a mounting bracket (not shown for clarity). The mounting bracket can be connected to the flow conduit 103A by known techniques such as welding, brazing, or bonding.

[0038] The coil section 204A also comprises a coil bobbin 220. The coil bobbin 220 may include a magnet receiving section 220' for housing at least a portion of the magnet 211. The coil bobbin 220 comprises a coil 222. The coil bobbin 220 can be held to the mounting bracket 210 by a fastening device.

[0039] Figures 3 and 4 illustrate embodiments of the present invention in which the coil portion 204A and the magnet portion 204B of the transducer assembly 200 are provided with physical stoppers to prevent them from colliding with each other within the range of motion associated with the movement of the conduits 103A and 103B in the X-axis direction. A plate 300 is provided that can be attached to the conduits 103A and 103B. The plate 300 is preferably attached to the conduits 103A and 103B by soldering, welding, brazing, bonding, and / or mechanically. The plate 300 can be manufactured subtractively or additively by punching, machining, or other methods. In the case of a flow meter having metal conduits 103A and 103B, the plate 300 is preferably made of metal to accommodate soldering, welding, or brazing. For plates 300 used on nonmetallic conduits 103A and 103B, plates 300 may be made from nonmetallic materials such as plastics, polymers, ceramics, composite materials, and any other materials known in the art.

[0040] The same shaped plate can be used for both conduits 103A and 103B. This reduces manufacturing costs because only one design needs to be created and simply duplicated. Furthermore, the symmetrical design prevents installation errors during the assembly process, as only one orientation fits together with the others.

[0041] In the nested fork region 302, a tine 304 formed on one side of plate 300 is fitted into a slot 306 formed in the adjacent plate 300 via a gap fit. The tine 304 does not extend completely to the base 308 of the slot 306. The width W of each tine 304 T Each slot has a width of 306W SIt is smaller than the gap C between the tine 304 and the slot 306, which determines the allowable amount of movement of the conduits 103A and 103B in the X-axis direction before the tine 304 and the slot 306 come into contact. The gap is configured to be smaller than the distance between the coil portion 204A and the magnet portion 204B of the transducer assembly 200, thus preventing collision between the coil portion 204A and the magnet portion 204B.

[0042] In one embodiment, brazing paste holes 310 are formed in each plate 300. Although three holes are shown, there may be more or fewer holes than three. The brazing paste holes 310 may contain brazing filler material for manufacturing purposes.

[0043] In one embodiment, the plate 300 may be provided with one or more balance holes 312. The balance holes 312 are sized to remove material such that the mass of the plate 300 is balanced with respect to the centerline of the flow conduit to which it is attached, the brazing paste hole 310, or both the centerline of the flow conduit and the brazing paste hole.

[0044] Although two tines 304 and two slots 306 are shown, the size and number of both the tines 304 and slots 306 are all changeable, and the mass and / or deformation strength of the part can be changed.

[0045] Brazing is a possible method for attaching the components to the flow conduit, but welding, mechanical attachment, and adhesive attachment are also possible.

[0046] Figures 5 and 6 show an alternative embodiment in which the coil portion 204A and the magnet portion 204B of the transducer assembly 200 are provided with physical stoppers to prevent them from colliding with each other within the range of motion associated with the movement of the conduits 103A and 103B in the X-axis direction.

[0047] This embodiment is constructed by first fixing two sets of nested bars 500 to the pipe by welding, brazing, bonding, clamping, or any combination of these methods. The restrictor 502 is inserted into an opening 503 provided at the end of one of the nested bars 500. The distance the restrictor 502 protrudes into the space 504 determines the amount of movement in the X-axis that the conduits 103A and 103B can move before the nested bars 500 collide and their further movement is prevented.

[0048] During manufacturing, in one embodiment, the restrictor 502 advances until it reaches a spacer (not shown) inserted into the space, where the thickness of the spacer represents the amount of movement in the X-axis of the conduits 103A, 103B that the nested bar 500 can move before impact. The restrictor 502 is then fixed in place by adhesive, tack welding, lock wire, or other means. The spacer is removed to provide clearance so that the conduit can vibrate in the Z-axis.

[0049] In one embodiment, the limiting body 502 is threaded, and the opening 503 includes a meshing thread. In one embodiment, the limiting body 502 is a screw. By providing a screw, or any other embodiment of the limiting body 502, the manufacturer can precisely limit the x-axis movement of one tube relative to the other and compensate for imperfect bar alignment and sensor distortion as the sensor assembly goes through the brazing and welding process. In one embodiment, after adjustment, the limiting body 502 is fixed in place by adhesive, threadlocker, welding, brazing, or mechanical means.

[0050] In the illustrated embodiment, the nested bars 500 are symmetrical. This prevents assembly errors because the orientation of the assembly is clear to the manufacturer. Furthermore, only one design needs to be manufactured, thereby reducing manufacturing costs. In addition, the use of identical parts helps maintain the mass balance of the conduit.

[0051] Figures 7 and 8 show the improved coil and retaining bracket assembly 700. In this embodiment, each conduit 103A, 103B has a portion of the retaining bracket assembly 700 attached to it. A first bracket 702 is attached to one conduit 103A, and a second bracket 704 is attached to the other conduit 103B. The first bracket 702 functions as a physical attachment point for the magnet portion 204B of the transducer assembly 200, and the second bracket 704 functions as a physical attachment point for the coil portion 204A of the transducer assembly 200. The retaining bracket assembly 700 allows the conventional transducer assembly 200 to be attached to the conduits 103A, 103B, and further provides protection from undesirable movement in both the x-axis and y-axis directions. Each bracket 702, 704 is provided with at least one passage 707 through which a restrictor 706 can pass. Each restrictor 706 extends from its respective bracket 702 or 704 and occupies a space 708 provided in the opposing bracket 704 or 702. In one embodiment, a shoulder 710 provided on each restrictor 706 defines a protruding portion 712 that occupies the space 708 defined in the opposing bracket 704. As a result of the restrictor 706 occupying the space 708, whether the restrictor 706 itself or the protruding portion 712, movement in the x and y directions is restricted by contact between the restrictor 706 and the wall 716 of the space 708. In one embodiment, the restrictor 706 occupies the space 708 concentrically with respect to the wall 716. This makes the restriction of movement in the x and y directions equal.

[0052] In one embodiment, at least one weight 718 is provided to maintain the mass balance and moment of inertia of the conduit around the central vertical axis. The position of the weight 718 is adjustable so that the mass balance and moment of inertia can be finely tuned.

[0053] An adjustment screw 720 may be provided to adjust the distance between the coil portion 204A and the magnet portion 204B. Alternatively, or in addition to the above, an adjustment screw 722 may be provided to adjust the distance between the magnet portion 204B and the coil portion 204A.

[0054] As shown in the figure, the configuration of the restrictor 706 features a symmetrical design to prevent assembly errors, ensuring that only properly coupled bracket assemblies 700 can be mounted. Brazing is a possible method for attaching the bracket assembly 700 to the flow conduit, but welding, mechanical mounting, clamping, and adhesive mounting are also possible.

[0055] The detailed description of the embodiments described above is not an exhaustive description of all embodiments intended by the inventors to be within the scope of this description. In fact, those skilled in the art will recognize that further embodiments can be created by combining or omitting certain elements of the embodiments described above, and that such further embodiments fall within the scope of this specification and teachings. It will also be apparent to those skilled in the art that additional embodiments can be created within the scope of this specification and teachings by combining the embodiments in whole or in part.

[0056] Therefore, although specific embodiments are described herein for illustrative purposes, various equivalent modifications are possible within the scope of this specification, as will be understood by those skilled in the art. The teachings provided herein are applicable not only to the embodiments described above and shown in the accompanying figures, but also to other flowmeters. Accordingly, the scope of this embodiment should be determined by the following claims.

Claims

1. A coil section (204A) comprising a coil bobbin (220) and a coil (222) wound on the coil bobbin (220), A magnet section (204B) equipped with a magnet (211), A first bracket (702) attached to a conduit (103A), to which the magnet portion (204B) is attached, A second bracket (704) attached to another conduit (103B), to which the coil portion (204A) is attached, and A restricting body (706) extending from the first bracket (702) to the space (708) within the second bracket (704), wherein the contact between the restricting body (706) and the wall (716) of the space (708) determines the restriction of movement between the first bracket (702) and the second bracket (704). Equipped with, A transducer assembly (200) for a vibration meter (5) having meter electronic equipment (20), wherein the coil portion (204A) and the magnet portion (204B) are restricted so as to prevent the coil portion (204A) from colliding with the magnet portion (204B).

2. The transducer assembly (200) according to claim 1, wherein the restricting body (706) occupies the space (708) in a concentric manner with respect to the wall (716) of the space (708).

3. The transducer assembly (200) according to claim 1, further comprising a second restricting member (706) extending from the second bracket (704) to the space (708) within the first bracket (702), wherein contact between the second restricting member (706) and the wall (716) of the space (708) determines a second limit on movement between the first bracket (702) and the second bracket (704).

4. The transducer assembly (200) according to claim 1, wherein at least one weight (718) is provided on at least one of the first and second brackets (702, 704) to maintain the mass balance and moment of inertia of the conduit (103A) and the conduit (103B) about a central vertical axis.

5. A method for forming a vibration meter, which includes a sensor assembly having one or more conduits, Steps include fixing the coil section to the conduit and The steps include fixing the magnet part to another conduit, A step of attaching a first bracket to the conduit, wherein the magnet portion is attached to the first bracket, A step of attaching a second bracket to the conduit, wherein the coil portion is attached to the second bracket, A step of extending a restricting body from the first bracket to the space within the second bracket, wherein the contact between the restricting body and the wall of the space determines the restriction of movement between the first bracket and the second bracket. Includes, A method in which the coil portion and the magnet portion are restricted so that the coil portion does not collide with the magnet portion.

6. A method for forming a vibration meter according to claim 5, wherein the movement of the coil portion and the magnet portion is restricted in both directions of the x-axis and the y-axis, where the x-axis is along the axis of the conduit and the y-axis is perpendicular to the direction in which the x-axis and the restricting body extend.

7. A method for forming a vibration meter according to claim 5, wherein the axial movement of the conduit of the coil portion and the magnet portion is restricted by a physical stopper.

8. The physical stopper comprises multiple bars, each conduit comprises a bar, and the bars are configured to be nested within each other. A method for forming a vibration meter according to claim 7, wherein a restricting body is inserted into an opening provided at the end of at least one nested bar, and the amount of axial movement the conduit can move before the nested bars collide and further movement is prevented is determined by the distance the restricting body protrudes into the space between the nested bars.

9. The physical stopper comprises a first and a second plate, A step of forming a tine on one side of the plate, A step of forming a slot on the opposite side of the plate, and The step includes positioning the tines within the slots in a gap-fit ​​configuration to form nested fork regions, A method for forming a vibration meter according to claim 7, wherein the width of each tine is smaller than the width of each slot, and the gap between the tine and the slot determines the amount of conduit movement allowed in the axial direction of the vibration meter before contact occurs between the tine and the slot, and the gap is configured to be smaller than the distance between the coil portion and the magnet portion of the transducer assembly.

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