TRANSDUCER FOR A VIBRATING FLUID METER

Abstract

A transducer assembly (300) for a vibrating meter having meter electronics (20) is provided. The transducer assembly (300) comprises a keeper portion (401) comprising a keeper plate (402). A magnet portion (301) comprises a coil bobbin (305) and a coil (309) wound around the coil bobbin (305). A magnet (313) is coupled to the coil bobbin (305). The keeper plate (402) is prevented from contacting the coil bobbin (305).

Claims

1. A transducer assembly (300) for a vibrating meter having meter electronics (20), comprising: a keeper portion (401) comprising a keeper plate (402); a magnet portion (301) comprising: a coil bobbin (305); a coil (309) wound around the coil bobbin (305); a magnet (313) coupled to the coil bobbin (305); and wherein the keeper plate (402) is prevented from contacting the coil bobbin (305).

2. The transducer assembly (300) of claim 1, comprising a flux ring (307) disposed to circumscribe at least a portion of the coil bobbin (305).

3. The transducer assembly (300) of claim 1, comprising a flux ring (307) disposed to circumscribe at least a portion of the coil (309).

4. The transducer assembly (300) of claim 1, wherein the magnet (313) is coupled to the coil bobbin (305) with a pole piece (311).

5. The transducer assembly (300) of claim 1, wherein the magnet (313) is a permanent magnet.

6. The transducer assembly (300) of claim 1, wherein the coil bobbin (305), the coil (309), and the magnet (313) are fixed in place with relation to each other.

7. The transducer assembly (300) of claim 1, wherein the meter electronics (20) provides an oscillating current to the coil (309) that induces motion of the keeper plate (402).

8. The transducer assembly (300) of claim 1, wherein the keeper portion (401) and the magnet portion (301) are coupled to first and second portions of the vibrating meter, respectively, wherein at least one of the first and second portions of the vibrating meter comprise a flow conduit (103A, 103B).

9. A method for forming a vibrating meter including a sensor assembly with one or more flow conduits, comprising steps of: forming a keeper portion comprising a keeper plate; coupling the keeper portion to a first component of the vibrating meter; forming a magnet portion comprising a coil bobbin; coupling the magnet portion to a second component of the vibrating meter; winding a coil around the coil bobbin; coupling a magnet to the coil bobbin; placing the keeper plate proximate the magnet; electrically coupling the coil to a meter electronics.

10. The method of claim 9, wherein the first component and second component comprise at least one flow conduit.

11. The method of claim 9, further comprising the step of circumscribe at least a portion of the coil bobbin with a flux ring.

12. The method of claim 9, further comprising the step of coupling the magnet to the coil with a pole piece.

13. The method of claim 9, further comprising the step of fixing the coil bobbin, coil, and magnet in place with relation to each other.

14. The method of claim 9, further comprising the step of providing an oscillating current to the coil that induces motion of the keeper plate.

15. The method of claim 9, further comprising the step of receiving an oscillating current from the coil, wherein the oscillating current is induced by the motion of the keeper plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 shows a prior art fluid meter.

[0032] FIG. 2 shows a cross-sectional view of a prior art transducer assembly.

[0033] FIG. 3 shows a magnet portion of a transducer assembly according to an embodiment.

[0034] FIG. 4 shows a keeper portion of a transducer assembly according to an embodiment.

[0035] FIG. 5 shows a cross-sectional view of a transducer assembly according to an embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0036] FIGS. 3-5 and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of embodiments of a transducer. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these examples that fall within the scope of the present description. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the fluid meter. As a result, the embodiments described below are not limited to the specific examples described below, but only by the claims and their equivalents.

[0037] FIG. 2 shows a cross-sectional view of a prior art transducer assembly 200. The transducer assembly 200 can be coupled to the first and second flow conduits 103A, 103B. The prior art transducer assembly 200 comprises a coil portion 204A and a magnet portion 204B. The magnet portion 204B comprises a magnet 211. The magnet 211 can be positioned within a magnet keeper 213 that can help direct the magnetic field. The magnet portion 204B may also comprise a pole piece 215. The magnet portion 204B comprises a typical magnet portion of prior art sensor components. The magnet portion 204B may be coupled to the second flow conduit 103B with a mounting bracket (not shown for clarity). The mounting bracket may be coupled to the flow conduit 103B according to well-known techniques such as welding, brazing, bonding, etc.

[0038] The coil portion 204A may be coupled to the first flow conduit 103A with a mounting bracket (not shown for clarity). The mounting bracket may be coupled to the flow conduit 103A according to well-known techniques such as welding, brazing, bonding, etc.

[0039] The coil portion 204A also comprises a coil bobbin 220. The coil bobbin 220 can include a magnet receiving portion 220′ for receiving at least a portion of the magnet 211. The coil bobbin 220 comprises a coil 222. The coil bobbin 220 can be held onto the mounting bracket 210 with a fastening device.

[0040] FIG. 3 shows a magnet portion 301 of a transducer assembly 300 (shown in FIG. as a cross section) according to an embodiment. A bracket 303 is attached to the coil bobbin 305. The bracket 303 may be coupled to the coil bobbin 305 with a mechanical fastener, adhesive, by welding/brazing, or by other methods known in the art. The particular method used to couple the coil bobbin 305 to the bracket 303 should in no way limit the scope of the present embodiment. In an embodiment, the bracket 303 and coil bobbin 305 are formed from the same piece of material. The forming of the bracket 303 and coil bobbin 305 may be through machining operations, casting/molding operations, 3D printing or similar additive manufacturing methods.

[0041] The coil bobbin 305 may be plastic, ceramic, polymeric, or otherwise non-magnetic. In an embodiment, the coil bobbin 305 may be made from ferrous materials. A flux ring 307 may circumscribe a portion of the coil bobbin 305. The flux ring 307 may also circumscribe a portion or all of a coil 309 (see FIG. 5) wound around the coil bobbin 305. The flux ring 307 may be formed from carbon steel or another mu metal, and aids in isolating the electric fields associated with the individual wires in the system. A pole piece 311 is coupled to the inner diameter of the coil bobbin 305 and moves with the coil bobbin 305, thus forming part of a magnetic circuit. A magnet 313 is coupled to the pole piece 311, and moves with the pole piece/bobbin 311, 305 to form part of the magnetic circuit.

[0042] The axial position of the pole is optimized to maximize coil to pole coupling, and the bobbin hub thickness is minimized to maximize coil to pole coupling. The precise dimensions to achieve these optimizations differ depending on the size of the assembly, the size of the bobbin, the number of coil windings, the strength of the magnet, the throw of the transducer, etc., as will be understood by those skilled in the art.

[0043] FIGS. 4 and 5 shows a keeper portion 401 of the transducer assembly 300 (shown in FIG. 5). A keeper plate 402 is coupled to a bracket 403. The bracket 403 may be coupled to the keeper plate 402 with a mechanical fastener, adhesive, by welding/brazing, or by other methods known in the art. The particular method used to couple the keeper plate 402 to the bracket 403 should in no way limit the scope of the present embodiment.

[0044] It will thus be appreciated that this is a large departure from prior art transducers, as virtually all components of the proposed transducer assembly 300 are arranged on a single side/bracket. That is to say that the magnet 313 and pole piece 311 that magnetically interact with the coil/coil bobbin 309, 305 are not only situated on the same bracket 303 but are fixed in place with relation to each other.

[0045] In an embodiment the magnet 313 is a permanent magnet, though an electromagnet is contemplated. The magnet in the proposed invention will create a magnetic circuit through the adjacent components and attract the keeper plate 402. An oscillating current through the coil 309 will increase/decrease the force on the keeper plate 402 causing it to oscillate. The transducer assembly 300 is constructed such that it may be used as both a driver and a pickoff sensor. The transducer circuits will operate in the same way mechanically as the prior art but output a voltage proportional to the magnet/keeper plate gap. The invention will thus behave like existing drive and pickoff circuits but eliminate the above-noted problems related to coil/keeper positioning issues and misalignment and sources of lateral movement.

[0046] The transducer assembly 300 is generally coupled to a dual flow conduit sensor assembly, in other embodiments, one of the portions 303, 403 may be coupled to a stationary component or a dummy tube, or balance bar, or case component, for example. This may be the case in situations where the combined transducer assembly 300 is utilized in a single flow conduit sensor assembly.

[0047] Although not shown for clarity, it should be appreciated that meter electronics 20 can communicate with a wire lead similar to the wire 110 shown in FIG. 1. Therefore, when in electrical communication with the meter electronics 20, the transducer assembly 300 can be provided with a drive signal in order to create motion between the magnet portion 301 and the keeper portion 401. Likewise, the transducer assembly 300 can communicate with the meter electronics 20 with a wire lead similar to one of the wire leads 111, 111′ shown in FIG. 1. Therefore, when in electrical communication with the meter electronics, the transducer assembly 300 can sense motion between the magnet portion 301 and the keeper portion 401.

[0048] A vibrating meter, such as that shown in FIG. 1 may comprise the transducer assembly 300. The vibrating meter may comprise a Coriolis flow meter or some other vibratory meter. The vibrating meter can receive a fluid that may be flowing or stationary. The fluid may comprise a gas, a liquid, a gas with suspended particulates, a liquid with suspended particulates, a multiphase fluid, or a combination thereof.

[0049] The detailed descriptions of the above embodiments are not exhaustive descriptions of all embodiments contemplated by the inventors to be within the scope of the present description. Indeed, persons skilled in the art will recognize that certain elements of the above-described embodiments may variously be combined or eliminated to create further embodiments, and such further embodiments fall within the scope and teachings of the present description. It will also be apparent to those of ordinary skill in the art that the above-described embodiments may be combined in whole or in part to create additional embodiments within the scope and teachings of the present description.

[0050] Thus, although specific embodiments are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the present description, as those skilled in the relevant art will recognize. The teachings provided herein can be applied to other fluid meters, and not just to the embodiments described above and shown in the accompanying figures. Accordingly, the scope of the embodiments should be determined from the following claims.