Electrode assembly and electromagnetic flowmeter

Abstract

The utility model relates to an electrode assembly and an electromagnetic flowmeter. The electrode assembly is used for the electromagnetic flowmeter and comprises an electrode tip; and the first end part of the electrode extension rod is electrically connected with the electrode tip. And the second end part of the electrode extension rod is suitable for being electrically connected with an electrode lead of the electromagnetic flowmeter. The electromagnetic flowmeter comprises the electrode assembly. According to the electrode assembly and the electromagnetic flowmeter, reliable electric connection between the electrode extension rod and the electrode lead can be conveniently and rapidly established, reliable electric insulation between the electrode assembly and the metal tube can be provided, and reliable transmission of sensing signals is ensured.

Description

Technical Field

[0001] The utility model relates to an electromagnetic flowmeter, and more particularly to an electrode assembly for the electromagnetic flowmeter and the electromagnetic flowmeter with the electrode assembly. Background Art

[0002] The contents of this section merely provide background information related to the present invention and may not constitute prior art.

[0003] Electromagnetic flowmeters have been widely used in the measurement of fluid volume flow. The electromagnetic flowmeter mainly includes a metal pipe for the measured fluid to flow through, an electrode assembly for sensing the measured fluid, and a signal processing device electrically connected to the electrode assembly for processing the signal sensed by the electrode assembly. The stable transmission of the sensed signal from the electrode assembly to the signal processing device is crucial for the accurate measurement of the electromagnetic flowmeter. The electrode assembly is installed on the wall of the metal pipe to detect the signal generated in the measured fluid, and the signal sensed by the electrode head of the electrode assembly is transmitted to the signal processing device through the electrode extension rod and the electrode lead electrically connected to the electrode head, wherein the electrical connection between the electrode extension rod and the electrode lead is provided by the electrode terminal. In the design of the electrode assembly of the existing electromagnetic flowmeter, the annular electrode terminal is usually installed on the electrode extension rod and fixed by the electrode nut to form an electrical connection between the electrode extension rod and the electrode terminal, and the annular electrode terminal is led out to be electrically connected to the electrode lead, thereby providing an electrical connection between the electrode extension rod and the electrode lead through the annular electrode terminal, so that the signal sensed by the electrode assembly is transmitted to the signal processing device through the electrode lead. In this existing design, an insulating sleeve or insulating glue is easily sandwiched between the electrode terminal and the electrode nut, thereby affecting the stability of the electrode signal transmission. In addition, in order to provide a continuous preload, the electrode assembly of the electromagnetic flowmeter is also provided with a compression spring, but the metal tube and the metal gasket supporting the compression spring are insulated only by an insulating paper gasket with a thickness of about 0.5 mm. The insulation between the metal gasket supporting the compression spring and the metal tube is easily invalidated due to the inherent design defects of the insulating paper gasket, resulting in the electrode signal being unable to be stably transmitted through the electrode terminal.

[0004] Therefore, it is necessary to improve the design of the electrode assembly of the electromagnetic flowmeter to improve the stability of the electrode signal transmission of the electromagnetic flowmeter. Utility Model Content

[0005] The present utility model aims to improve the stable transmission of the sensing signal of an electromagnetic flowmeter. One object of the present utility model is to provide an improved electrical connection between the electrode extension rod and the electrode lead of the electrode assembly of the electromagnetic flowmeter, so as to improve the stability of the signal transmission of the electrode assembly. Another object of the present utility model is to improve the electrical insulation between the electrode assembly of the electromagnetic flowmeter and the metal pipe, thereby further providing the stability of the signal transmission of the electrode assembly. Still another object of the present utility model is to simplify the structure and installation of the electrode assembly.

[0006] One aspect of the present utility model is to provide an electrode assembly for an electromagnetic flowmeter, which includes: an electrode head; and an electrode extension rod, the first end of the electrode extension rod is electrically connected to the electrode head. The second end of the electrode extension rod is adapted to be electrically connected to the electrode lead of the electromagnetic flowmeter.

[0007] In one embodiment, the electrode assembly further includes an electrode terminal, and the electrode terminal is adapted to electrically connect the second end of the electrode extension rod to the electrode lead at the second end of the electrode extension rod.

[0008] In one embodiment, the electrode terminal is mounted at the second end of the electrode extension rod such that the second end of the electrode extension rod and the metal core wire of the electrode lead are press riveted together.

[0009] In one embodiment, the second end of the electrode extension rod and the electrode lead are also welded together.

[0010] In one embodiment, the electrode terminal and the metal core wire of the electrode lead are crimped together and welded to the second end of the electrode extension rod.

[0011] In one embodiment, the electrode terminal is a cylindrical part, and the electrode terminal is adapted to accommodate at least one of the second end of the electrode extension rod and the electrode lead within the electrode terminal.

[0012] In one embodiment, the second end of the electrode extension rod is adapted to be welded to the electrode lead of the electromagnetic flowmeter.

[0013] In one embodiment, the diameter of the second end of the electrode extension rod is smaller than the diameter of the remaining part of the electrode extension rod.

[0014] In one embodiment, the electrode extension rod includes an external thread portion between the first end and the second end, and the electrode assembly further includes an electrode nut that engages with the external thread portion.

[0015] In one embodiment, the electrode assembly further includes a compression spring and an insulating cup, the insulating cup is movably mounted on the electrode extension rod, and the compression spring is disposed between the electrode nut and the insulating cup and at least partially located within the insulating cup.

[0016] In one embodiment, the insulating cup includes an annular inner wall, an annular outer wall, and a bottom wall connecting the end of the annular inner wall and the end of the annular outer wall. The annular inner wall and the annular outer wall are spaced apart from each other in the radial direction of the insulating cup to jointly define an annular space open on one side with the bottom wall, and the compression spring is at least partially received in the annular space.

[0017] One or both of the annular inner wall and the annular outer wall form a stop portion, and the stop portion is adapted to prevent the compression spring from being further compressed in the annular space.

[0018] In one embodiment, the electrode assembly further includes a metal gasket, the metal gasket is disposed between the compression spring and the electrode nut, and the metal gasket is adapted to abut against the stop portion.

[0019] In one embodiment, the annular inner wall, the annular outer wall, and the bottom wall are integrally formed.

[0020] In one embodiment, the electrode assembly further includes an insulating sleeve, the insulating sleeve is mounted on the electrode extension rod, one end of the insulating sleeve is close to the electrode head, and the other end of the insulating sleeve overlaps at least a part of the annular inner wall in the axial direction.

[0021] Another aspect of the present utility model lies in providing an electromagnetic flowmeter, and the electromagnetic flowmeter includes the electrode assembly according to the present utility model.

[0022] The electromagnetic flowmeter further includes a metal pipe for the measured fluid to flow through, and an insulating lining is provided on the inner peripheral wall of the metal pipe to prevent the measured fluid from contacting the metal pipe. The electrode extension rod penetrates the insulating lining and the pipe wall of the metal pipe in the radial direction of the metal pipe, the electrode head is engaged with the insulating lining, and the end of the electrode head is located on the flow path of the measured fluid and can directly contact the measured fluid.

[0023] The electrode assembly and the electromagnetic flowmeter according to the present utility model can conveniently and quickly establish a reliable electrical connection between the electrode extension rod and the electrode lead by electrically connecting at the end of the electrode extension rod, ensuring the stable transmission of the sensing signal. And, the electrode assembly and the electromagnetic flowmeter according to the present utility model can further improve the reliable transmission of the sensing signal by using the insulating cup to provide reliable electrical insulation between the electrode assembly and the metal pipe for the measured fluid to flow through. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The embodiments of the present utility model will be described hereinafter only by way of example with reference to the drawings. In the drawings, the same features or components are denoted by the same reference numerals, and the drawings are not necessarily drawn to scale, and in the drawings:

[0025] Figure 1Shows a perspective view of a partially cut-away electromagnetic flowmeter according to an embodiment of the present invention;

[0026] Figure 2 is according to Figure 1 A perspective view of the electrode assembly of the electromagnetic flowmeter shown in;

[0027] Figure 3 Shows Figure 2 An exploded view of the electrode assembly shown in;

[0028] Figure 4 Shows Figure 1 A partial cross-sectional view of the electromagnetic flowmeter shown in, showing the installation of the electrode assembly; and

[0029] Figure 5 Shows a partial cross-sectional view of an electromagnetic flowmeter according to the related art. Detailed implementation manners

[0030] The following description is essentially exemplary only and is not intended to limit the present invention and its application and uses. It should be understood that in all the drawings, like reference numerals indicate the same or similar parts and features. Each drawing only schematically shows the concept and principle of the embodiment of the present invention and does not necessarily show the specific dimensions and their ratios of each embodiment of the present invention. The specific parts in a specific drawing may be exaggerated to illustrate the relevant details or structures of the embodiment of the present invention.

[0031] In the description of the embodiments of the present invention, the orientation terms related to "upper", "lower", "left", "right", "front", and "rear" are described in accordance with the orientation of upper, lower, left, right, front, and rear in the view.

[0032] Figure 1 Shows a perspective view of an electromagnetic flowmeter 100 according to an embodiment of the present invention. In Figure 1 it, a part of the electromagnetic flowmeter 100 is cut away to show its internal structure.

[0033] As Figure 1As shown, the electromagnetic flowmeter 100 includes a metal pipe 10 through which the fluid to be measured flows, and an insulating lining 20. The insulating lining 20 is provided on the inner peripheral wall of the metal pipe 10 and extends to the axial end faces of the flange portions 11 and 12 located at both ends of the metal pipe 10, providing insulation for the metal pipe 10. The electromagnetic flowmeter 100 further includes a housing 50 which surrounds the metal pipe 10, and an annular space for installing a magnetic circuit system (not shown in the figure) is formed between the outer peripheral wall of the metal pipe 10 and the housing 50. When the electromagnetic flowmeter 100 is respectively connected to the pipeline to be measured through the flange portions 11 and 12 for measurement, the fluid to be measured flows through the metal pipe 10, and under the action of the magnetic field of the magnetic circuit system provided on the outer side of the metal pipe 10, an induced voltage signal is generated in the fluid to be measured. When the fluid to be measured flows through the metal pipe 10, the insulating lining 20 prevents the fluid to be measured from contacting the metal pipe 10, thereby preventing the induced voltage signal generated when the fluid to be measured flows through the electromagnetic flowmeter 100 from being short-circuited due to the contact between the fluid to be measured and the metal pipe 10, ensuring that the induced voltage signal can be properly transmitted, and improving the corrosion resistance of the metal pipe 10.

[0034] The electromagnetic flowmeter 100 further includes an electrode assembly 30 (only a part of the electrode head 31 of the electrode assembly 30 is shown in Figure 1 ), the electrode assembly 30 is installed on the pipe wall of the metal pipe 10, penetrates the metal pipe 10 and the insulating lining 20 in the radial direction of the metal pipe 10, and the measuring part of the electrode head 31 of the electrode assembly 30 is located on the flow path of the fluid to be measured and can be in direct contact with the fluid to be measured. When the fluid to be measured flows through the metal pipe 10 and the insulating lining 20, the measuring part of the electrode head 31 of the electrode assembly 30 is in direct contact with the fluid to be measured to measure the induced voltage signal generated in the fluid to be measured. The electrode assembly 30 transmits the sensed induced voltage signal to the signal processing device (not shown in the figure, for example, including an amplifier, a converter, etc.) of the electromagnetic flowmeter 100 to convert it into a unified output signal (for example, the average flow velocity or average flow rate of the fluid to be measured).

[0035] Figure 2 The perspective view of the electrode assembly 30 is shown, Figure 3 The exploded view of the electrode assembly 30 is shown. Figure 4 Shown is Figure 1 The partial cross-sectional view of the electromagnetic flowmeter 100 in

[0036] As shown in Figure 2 and Figure 3As shown, the electrode assembly 30 includes an electrode head 31 and an electrode extension rod 33. The electrode head 31 is made of a conductive material and is configured to directly contact the fluid to be measured to sense the induced voltage signal generated when the fluid to be measured passes through the electromagnetic flowmeter 100. The electrode head 31 transmits the sensed induced voltage signal to the signal processing device of the electromagnetic flowmeter 100 through the electrode extension rod 33 made of a conductive material and the electrode lead 40.

[0037] The electrode head 31 is electrically connected to the first end portion 331 of the electrode extension rod 33 to transmit the sensed induced voltage signal through the electrode extension rod 33. In Figures 2 to 4 the embodiment shown, the electrode head 31 includes a connecting rod portion 311 and a flange portion 312. One end of the connecting rod portion 311 is electrically connected to the first end portion 331 of the electrode extension rod 33. The flange portion 312 is located at the other end of the connecting rod portion 311 and protrudes radially outward from the connecting rod portion 311. The connecting rod portion 311 of the electrode head 31 engages with the first end portion 331 of the electrode extension rod 33, such as by a threaded engagement. Since both the electrode head 31 and the electrode extension rod 33 are made of a conductive material, an electrical connection can be established between the electrode head 31 and the electrode extension rod 33 while a mechanical connection is formed by the threaded engagement between the connecting rod portion 311 of the electrode head 31 and the first end portion 331 of the electrode extension rod 33. However, the present utility model is not limited thereto, and the electrical connection between the electrode head 31 and the electrode extension rod 33 can also be established by other suitable means.

[0038] The second end portion 333 of the electrode extension rod 33 is adapted to be electrically connected to the electrode lead 40. In the example shown in the figure, the electrode assembly 30 further includes an electrode terminal 38. The electrode terminal 38 is adapted to electrically connect the second end portion 333 of the electrode extension rod 33 to the electrode lead 40 at the second end portion 333 of the electrode extension rod 33 to allow the induced voltage signal sensed by the electrode head 31 to be transmitted from the electrode extension rod 33 to the electrode lead 40 and thus to the signal processing device. The electrode terminal 38 can be a cylindrical member and is adapted to accommodate at least one of the second end portion 333 of the electrode extension rod 33 and the electrode lead 40 within the electrode terminal 38. In the example shown in the figure, optimally as Figure 4As shown, the electrode terminal 38 is provided on the second end portion 333 of the electrode extension rod 33 and is adapted to accommodate the second end portion 333 of the electrode extension rod 33 and a part of the electrode lead 40 within the electrode terminal 38. The electrode lead 40 includes a metal core wire 41 and one or more insulating layers 42 sleeved outside the metal core wire 41. The electrode terminal 38 accommodates the second end portion 333 of the electrode extension rod 33 and a part (end portion) of the metal core wire 41 of the electrode lead 40 within the electrode terminal 38. Preferably, the electrode terminal 38 rivets and connects the second end portion 333 of the electrode extension rod 33 and the metal core wire 41 of the electrode lead 40, such that the second end portion 333 of the electrode extension rod 33 is in direct contact with the metal core wire 41 of the electrode lead 40, thereby electrically connecting the electrode extension rod 33 and the electrode lead 40.

[0039] In Figures 2 to 4 the embodiment shown, the second end portion 333 of the electrode extension rod 33 is processed such that the diameter of the second end portion 333 is smaller than the diameter of the remaining part of the electrode extension rod 33, and the electrode terminal 38 is a cylindrical member made of copper or copper-plated. The second end portion 333 of the electrode extension rod 33 and the metal core wire 41 of the electrode lead 40 are riveted and connected within the electrode terminal 38. However, the present invention is not limited thereto. In other examples according to the present invention, the second end portion 333 of the electrode extension rod 33 and the electrode terminal 38 may also adopt other suitable forms, as long as the second end portion 333 of the electrode extension rod 33 can be easily riveted and connected to the metal core wire 41 of the electrode lead 40.

[0040] Preferably, while forming a press riveting connection between the electrode terminal 38 and the second end portion 333 of the electrode extension rod 33 and / or the electrode lead 40, welding (such as soldering or flame welding) can also be performed between the second end portion 333 of the electrode extension rod 33, the electrode lead 40 and / or the electrode terminal 38. For example, in one example, after the second end portion 333 of the electrode extension rod 33 is crimped together within the electrode terminal 38, spot welding can be performed at the exposed boundary of the metal core wire 41 of the electrode lead 40 to weld the electrode lead 40 to the second end portion 333 of the electrode extension rod 33 and / or the electrode joint 38. For example, the second end portion 333 of the electrode extension rod 33 can be nickel-plated. When the second end portion 333 of the electrode extension rod 33 and the metal core wire 41 of the electrode lead 40 are press riveted within the electrode terminal 38, soldering can also be performed on the electrode lead 40 and the second end portion 333 of the electrode terminal 33 and / or the electrode terminal 38 to strengthen the mechanical connection and electrical connection between them. This ensures that even in the extremely rare case where there is a gap at the riveted joint between the second end portion 333 of the electrode extension rod 33 and the metal core wire 41 of the electrode lead 40 and they are not completely connected to each other, the connection between the two can still be ensured through welding. For example, in another example, the electrode terminal 38 can accommodate a part of the electrode lead 40 within the electrode terminal 38 and press rivet it to the metal core wire 41 of the electrode lead 40, and be welded to the second end portion 333 of the electrode extension rod 33.

[0041] It should be noted here that in the example shown in the figure, the mechanical connection and electrical connection between the second end portion 333 of the electrode extension rod 33 and the electrode lead 40 are achieved through the electrode terminal 38. However, the present invention is not limited thereto. In another example according to the present invention, the electrode assembly 30 may not be provided with the above-mentioned electrode terminal 38, and the second end portion 333 of the electrode extension rod 33 can be welded to the electrode lead 40 to achieve the mechanical connection and electrical connection between the two.

[0042] The electrode assembly 30 further includes an electrode nut 37, and correspondingly, the electrode extension rod 33 further includes an external thread portion 332 located between the first end portion 331 and the second end portion 333. The electrode nut 37 is threadedly engaged with the external thread portion 332 of the electrode extension rod 33 to lock the electrode assembly 30 to the metal pipe 10 of the electromagnetic flowmeter 100, so as to ensure that the electrode assembly 30 does not become loose from the metal pipe 20 under various working conditions, and can be applicable to metal pipes 10 and insulating linings 20 with different pipe diameters and different wall thicknesses, and thus can be applicable to electromagnetic flowmeters with different pressure grades.

[0043] The electrode assembly 30 further includes a compression spring 35. The compression spring 35 is sleeved on the electrode extension rod 33 and is located between the electrode nut 37 and the electrode head 31, and is used to provide a continuous pre-tightening force, so that the electrode assembly 30 can be continuously and stably mounted on the metal tube 10. In the example shown in the figure, the compression spring 35 is a helical spring, for example, a metal helical spring. As the electrode nut 37 is screwed relative to the electrode extension rod 33 towards the electrode head 31, the compression spring 35 is compressed. After the electrode assembly 30 is installed in place on the metal tube 10, the compression spring 35 can continuously apply force to the electrode nut 37 and the metal tube 10 to ensure the continuous and stable installation of the electrode assembly 30 on the metal tube 10. Preferably, the electrode assembly 30 further includes a metal gasket 36. The metal gasket 36 is disposed between the electrode nut 37 and the end of the compression spring 35, so as to evenly transmit force between the compression spring 35 and the electrode nut 37.

[0044] The electrode assembly 30 further includes an insulating cover cup 34. The insulating cover cup 34 can be made of PPS material or other suitable insulating materials. The insulating cover cup 34 is movably mounted on the electrode extension rod 33 and is disposed between the compression spring 35 and the electrode head 31, so as to provide insulation between the compression spring 35 and the metal tube 10, and to space the compression spring 35 from the electrode extension rod 33, and at the same time provide a reliable support for the compression spring 35. Optimally as Figure 4 shown, the insulating cover cup 34 includes an annular outer wall 341, an annular inner wall 342, and a bottom wall 343 connecting one end of the annular outer wall 341 and one end of the annular inner wall 342. The annular outer wall 341 and the annular inner wall 342 are spaced apart from each other in the radial direction of the insulating cover cup 34 to jointly define an annular space V that is open on one side with the bottom wall 343. The compression spring 35 is at least partially received in the annular space V.

[0045] When installed in place, the electrode nut 37 engages with the external threaded portion 332 of the electrode extension rod 33 such that the metal tube 10 and the insulating lining 20 are clamped between the bottom wall 343 of the insulating cup 34 and the flange portion 312 of the electrode head 31. The bottom wall 343 of the insulating cup 34 provides insulation between the compression spring 35 and the metal tube 10, and the annular inner wall 342 of the insulating cup 34 spaces the compression spring 35 and the electrode extension rod 33 apart from each other. Specifically, for the portion of the compression spring 35 received in the annular space V, this portion of the compression spring 35 is spaced apart from the electrode extension rod 33 due to the annular inner wall 342 being located between the compression spring 35 and the electrode extension rod 33. For the portion of the compression spring 35 located outside the receiving space V, this portion of the compression spring 35 is spaced apart from the electrode extension rod 33 in the radial direction, and although the annular inner wall 342 is not clamped between this portion of the compression spring 35 and the electrode extension rod 33, due to the restricting effect of the annular inner wall 342 on the compression spring 35, this portion of the compression spring 35 and the electrode extension rod 33 do not come into contact with each other. Preferably, the annular outer wall 341, the annular inner wall 342, and the bottom wall 343 are integrally formed. In the example shown in the figure, the annular outer wall 341 and the annular inner wall 342 have substantially the same axial height. However, the present utility model is not limited thereto. In other examples according to the present utility model, the annular outer wall 341 and the annular inner wall 342 may have different axial heights.

[0046] In addition, the insulating cup 34 can also be used to limit further compression of the compression spring 35 in the annular space V. One or both of the annular outer wall 341 and the annular inner wall 342 of the insulating cup 34 form a stop portion for preventing the compression spring 35 from being further compressed in the annular space V. In the example shown in the figure, the electrode assembly 30 includes a metal gasket 36, and the stop portion (e.g., the annular inner wall 342) is adapted to abut against the metal gasket 36 to limit further compression of the compression spring 35 in the annular space V. However, the present utility model is not limited thereto. In other examples without the metal gasket 36, the stop portion is adapted to abut against the electrode nut 37.

[0047] The electrode assembly 30 further includes an insulating sleeve 32. The insulating sleeve 32 is mounted on the electrode extension rod 33 for providing insulation between the electrode extension rod 33 and the metal tube 10. In the example shown in the figure, the connecting rod portion 311 of the electrode head 31 is threadedly engaged within the first end portion 331 of the electrode extension rod 33. The insulating sleeve 32 is mounted on the outer peripheral surface of the electrode extension rod 33. One end of the insulating sleeve 32 is close to or abuts against the flange portion 312 of the electrode head 31, and the other end portion (the upper end portion in the figure) of the insulating sleeve 32 extends to overlap at least a part of the annular inner wall 342 of the insulating cup 34 in the axial direction, preventing the electrode extension rod 33 from contacting the metal tube 10, thereby providing insulation between the electrode extension rod 33 and the metal tube 10. The insulating sleeve 32 at least covers the first end portion 331 of the electrode extension rod 33. As Figure 4 shown, when installed in place, the insulating sleeve 32 covers the first end portion 331 of the electrode extension rod 33 and also covers a part of the external thread portion 332.

[0048] In the embodiment shown in the figure, the flange portion 312 of the electrode head 31 engages with the insulating lining 20 to prevent the electrode head 31 from completely passing through the insulating lining 20 or the metal tube 10 so that the electrode assembly 30 is installed in place on the metal tube 10. And the flange portion 312 of the electrode head 31 is at least partially embedded in the insulating lining 20, and the end portion (measurement portion) of the flange portion 312 projects partially from the inner wall of the insulating lining 20, as Figure 4 shown. Preferably, the electrode assembly 30 can be installed such that the end of the electrode head 31 is flush with the inner wall of the insulating lining 20, so that the fluid to be measured is not obstructed by the electrode head 31 when flowing through the insulating lining 20.

[0049] The electromagnetic flowmeter 100 and its electrode assembly 30 according to the first embodiment of the present invention are introduced above.

[0050] Figure 5 The structure and installation of the electrode assembly 60 of an electromagnetic flowmeter according to the related art are shown. As Figure 5 shown, the electrode assembly 60 according to the related art includes an electrode head 61, an insulating sleeve 62, an electrode extension rod 63, a compression spring 65, a metal gasket 66, an electrode gasket 70, an electrode nut 67, an electrode terminal 68, an outer sleeve 73, an inner sleeve 74, a metal gasket 71, and an insulating paper gasket 72.

[0051] As Figure 5As shown, the electrode terminal 68 is designed in a ring shape, sleeved on the electrode extension rod 63, and clamped between the metal gasket 66 and the metal gasket 70 by the electrode nut 67 to form an electrical connection between the electrode terminal 68 and the electrode extension rod 63. Moreover, the lead-out part of the electrode terminal 68 is electrically connected to the electrode lead (not shown in the figure) of the electromagnetic flowmeter, thereby providing an electrical connection between the electrode extension rod 60 and the electrode lead, allowing the induced voltage signal sensed by the electrode head 61 to be transmitted to the signal processing device of the electromagnetic flowmeter.

[0052] Regarding the design where the ring-shaped electrode terminal 68 is sleeved on the electrode extension rod 63 and clamped between the metal gasket 66 and the metal gasket 70 by the electrode nut 67, during installation, it is easy to accidentally clamp the insulating sleeve 62 or insulating glue between them, resulting in too high a resistance between the ring-shaped electrode terminal 68 and the metal gasket 66, the metal gasket 70, or the electrode nut 67, which is not conducive to the transmission of the induced voltage signal and may even cause the electromagnetic flowmeter to fail due to excessive resistance.

[0053] In addition, as Figure 5 shown, the electrode assembly 60 also uses an outer sleeve 73 and an inner sleeve 74 to accommodate the compression spring 65, uses the metal gasket 71 to provide support for the compression spring 65, and uses the insulating paper gasket 72 to provide insulation between the compression spring 65 and the metal gasket 71 and the metal tube 10 through which the fluid to be measured flows, to prevent the sensed induced voltage signal from being transmitted to the metal tube 10 through the compression spring 65 during transmission. In the existing design, the insulating paper gasket 72 is usually, for example, an insulating paper gasket with a thickness of 0.5 mm. During installation and use, it is easy to fail due to the inherent design defects of the insulating paper gasket 72, thus being unable to provide insulation between the compression spring 65 and the metal gasket 71 and the metal tube 10, resulting in the induced voltage signal sensed by the electrode head 61 being transmitted back to the metal tube 10 through the compression spring 65, and thus being unable to be stably transmitted to the electrode lead and the signal processing device through the electrode terminal 68. In addition, since the electrode assembly 60 includes many components such as the metal gasket 71, the metal gasket 66, the metal gasket 70, the insulating paper gasket 72, the outer sleeve 73, and the inner sleeve 74 as described above, the installation of the electrode assembly 60 is also rather cumbersome.

[0054] In contrast, in the electromagnetic sensor 1 according to the present utility model, the electrode assembly 30 is electrically connected to the electrode lead 40 at the second end 333 of the electrode extension rod 33, without achieving the electrical connection between the electrode extension rod 33 and the electrode lead by clamping the electrode terminal between the middle portions of the electrode extension rod 33 through the electrode nut 37. Through this design, it is possible to completely avoid clamping the insulating sleeve 32 or the insulating glue for providing insulation to the connection between the electrode extension rod 33 and the electrode lead, which is conducive to the stable transmission of the induced voltage signal from the electrode head 31 through the electrode extension rod 33 and the electrode lead 40 to the signal processing device. And, preferably, the electrode assembly 30 uses the electrode terminal 38 to electrically connect the second end 333 of the electrode extension rod 33 and the electrode lead 40 to each other at the second end 333 of the electrode extension rod 33. And more preferably, the electrode terminal 38 accommodates the second end 333 of the electrode extension rod 33 and the metal core wire 41 of the electrode lead 40 inside the electrode terminal 38 and rivets them to each other. Compared with the above-mentioned existing design of clamping the annular electrode terminal between two metal gaskets through the electrode nut, the electrode assembly 30 proposed by the present utility model can easily and reliably electrically connect the second end 333 of the electrode extension rod 33 and the electrode lead 40 to each other, so that the assembly can be more convenient and rapid.

[0055] In addition, in the electromagnetic sensor 1 according to the present utility model, the insulating cover cup 34 is used to provide support for the compression spring 35, and can also stably and effectively provide electrical insulation between the compression spring 35 and the metal tube 10, and space the compression spring 35 and the electrode extension rod 33 apart from each other without contacting or interfering with each other. Compared with Figure 5 the electrode assembly 60 of the above-mentioned related art shown, the number of parts of the electrode assembly 30 according to the present utility model is significantly less and the structure is also simpler, ensuring the effective insulation of the electrode assembly 30 with a simple structure and making the assembly of the electrode assembly 30 simpler.

[0056] Herein, the exemplary embodiments of the electromagnetic flowmeter and its electrode assembly according to the present utility model have been described in detail, but it should be understood that the present utility model is not limited to the specific embodiments described and illustrated above in detail. Without departing from the gist and scope of the present utility model, those skilled in the art can make various combinations, modifications and variations to the present utility model. All such combinations, modifications and variations fall within the scope of the present utility model. Moreover, all the components described herein can be replaced by other technically equivalent components.

Claims

1. An electrode assembly for an electromagnetic flowmeter, comprising: An electrode head; And An electrode extension rod, a first end of the electrode extension rod being electrically connected to the electrode head, Characterized in that a second end of the electrode extension rod is adapted to be electrically connected to an electrode lead of the electromagnetic flowmeter.

2. The electrode assembly according to claim 1, wherein The electrode assembly further includes an electrode terminal, and the electrode terminal is adapted to electrically connect the second end of the electrode extension rod to the electrode lead at the second end of the electrode extension rod.

3. The electrode assembly according to claim 2, wherein The electrode terminal is mounted at the second end of the electrode extension rod such that the second end of the electrode extension rod and a metal core wire of the electrode lead are press-riveted together.

4. The electrode assembly according to claim 3, wherein The second end of the electrode extension rod and the electrode lead are also welded together.

5. The electrode assembly according to claim 2, characterized in that, The electrode terminal and the metal core wire of the electrode lead are press-riveted together and welded to the second end of the electrode extension rod.

6. The electrode assembly according to claim 2, wherein, The electrode terminal is a cylindrical member, and the electrode terminal is adapted to accommodate at least one of the second end of the electrode extension rod and the electrode lead within the electrode terminal.

7. The electrode assembly according to claim 1, characterized in that The second end of the electrode extension rod is adapted to be welded to an electrode lead of the electromagnetic flowmeter.

8. The electrode assembly according to any one of claims 1-7, characterized in that The diameter of the second end of the electrode extension rod is smaller than the diameter of the remaining portion of the electrode extension rod.

9. The electrode assembly according to any one of claims 1-7, characterized in that, The electrode extension rod includes an external thread portion located between the first end and the second end, and the electrode assembly further includes an electrode nut, and the electrode nut engages with the external thread portion.

10. The electrode assembly according to claim 9, wherein, The electrode assembly further includes a compression spring and an insulating cup, the insulating cup being movably mounted on the electrode extension rod, the compression spring being disposed between the electrode nut and the insulating cup and at least partially located within the insulating cup.

11. The electrode assembly according to claim 10, wherein, The insulating cup includes an annular inner wall, an annular outer wall, and a bottom wall connecting an end of the annular inner wall and an end of the annular outer wall. The annular inner wall and the annular outer wall are spaced apart from each other in the radial direction of the insulating cup to jointly define an annular space open at one side with the bottom wall, and the compression spring is at least partially accommodated in the annular space.

12. The electrode assembly according to claim 11, wherein, One or both of the annular inner wall and the annular outer wall form a stop portion, and the stop portion is adapted to prevent the compression spring from being further compressed in the annular space.

13. The electrode assembly according to claim 12, wherein The electrode assembly further includes a metal gasket, the metal gasket being disposed between the compression spring and the electrode nut, and the metal gasket being adapted to abut against the stop portion.

14. The electrode assembly according to claim 11, characterized in that, The annular inner wall, the annular outer wall, and the bottom wall are integrally formed.

15. The electrode assembly according to claim 14, wherein, The electrode assembly further includes an insulating sleeve, the insulating sleeve being mounted on the electrode extension rod, one end of the insulating sleeve being close to the electrode head, and the other end of the insulating sleeve overlapping at least a portion of the annular inner wall in the axial direction.

16. An electromagnetic flowmeter, characterized in that Including the electrode assembly according to any one of claims 1-15.

17. The electromagnetic flowmeter according to claim 16, characterized in that, The electromagnetic flowmeter further includes a metal pipe through which the fluid to be measured flows, and an insulating lining is provided on an inner peripheral wall of the metal pipe to prevent the fluid to be measured from contacting the metal pipe. Wherein, the electrode extension rod penetrates the insulating lining and the tube wall of the metal tube in the radial direction of the metal tube, the electrode head is joined to the insulating lining, and the end of the electrode head is located on the flow path of the fluid to be measured and can be in direct contact with the fluid to be measured.

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