JPH0355063Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an electromagnetic flowmeter equipped with a ground ring connected to a case for a measuring tube.

[Prior art]

An electromagnetic flowmeter maintains the same potential as a conductive fluid flowing inside a measurement tube, uses this as a reference potential, and measures the flow rate using the electromotive force generated in the conductive fluid.

For this reason, electromagnetic flowmeters have conventionally been employed which have a structure in which a measuring tube and a conductive fluid are electrically connected by a ground ring screwed onto the flange of the measuring tube.

However, in this case, the ground ring becomes thicker,
If this was made of a high-quality material, it would be costly.

Therefore, a spring-like mounting piece is provided on the periphery of the earth ring, and this mounting piece is screwed to the flange of the measuring tube.

However, in this case, although the ground ring can be made a little thinner, there is a problem in that the mechanical strength when attaching the ground ring is insufficient.

[Summary of the idea]

The present invention was developed in view of these circumstances.A fitting portion is provided by extending the opening ends at both open ends of the cylindrical case that houses the measuring tube, and a thin plate-shaped portion is provided in the fitting portion. The present invention provides an electromagnetic flowmeter that can be manufactured economically and has high mechanical strength when the earth ring is attached by an extremely simple structure in which an annular gasket is fitted through the earth ring. Hereinafter, the configuration and the like will be explained in detail by referring to embodiments shown in the drawings.

〔Example〕

1 and 2 are a perspective view and a sectional view showing an embodiment of an electromagnetic flowmeter according to the present invention. In these figures, what is indicated by reference numeral 1 is a cylindrical case for an electromagnetic flowmeter, in which a measuring tube 2 is housed, and a notch 3 is formed at both open ends by extending the open ends. A fitting portion 4 is provided.
The measuring tube 2 has flanges 5 at both ends, and a space 6 formed on the outer peripheral surface side, that is, between both flanges 5.
A pair of excitation coils 7 are mounted facing each other via a core 8 containing the excitation coils. In addition, a pair of electrodes 9 (only one of which is shown) is arranged in the axial center of the measuring tube 2 at positions perpendicular to the flow direction of the fluid to be measured flowing inside the tube and the direction of the magnetic flux formed by the excitation coil 7. The sensor is configured to detect the electromotive force generated at each point of the fluid to be measured. Reference numeral 10 denotes a lining made of an insulating material such as Teflon, which is provided on the tube wall 2a and flange end surface 5a of the measuring tube 2. Reference numeral 11 denotes an annular gasket, which has a sealing function and a function of protecting an earth ring, which will be described later, and is fitted into the fitting portion 4. A protrusion 11a facing the notch 3 is integrally provided on the periphery of the gasket 11. 12 is a thin plate-shaped earth ring, which is interposed between the gasket 11 and the measurement tube 2;
A mounting piece 12a facing the notch 3 and screwed to the neck pedestal 1a of the case 1 is integrally protruded from the periphery. Thereby, the ground ring 12 is not only electrically connected to the case 1 but also mechanically fixed.

In the electromagnetic flowmeter configured in this way,
Since the earth ring 12 is interposed between the measuring tube 2 and the gasket 11, it is possible to use an extremely thin earth ring 12.

In addition, in order to attach the grounding ring 12 to the case 1, the mounting piece 12a of the grounding ring 12 should face the notch 3, and after fixing it to the screw base 1a,
Gasket 11 with protrusion 11a facing notch 3
What is necessary is just to fit into the fitting part 4.

Note that in this embodiment, the earth ring 12
Although an example has been shown in which the mounting piece 12a is fixed to the neck pedestal 1a of the case 1 with screws, the present invention is not limited to this. can also be implemented in the same way.

[Effect of idea]

As explained below, according to the present invention, the mounting piece protruding from the periphery of the thin plate-shaped ground ring is attached to the case so as to face the notch of the fitting part, so that sufficient mechanical strength can be ensured. However, it can be manufactured at a very low cost.

[Brief explanation of drawings]

1 and 2 are a perspective view and a sectional view showing an electromagnetic flowmeter according to the present invention, and FIG. 3 is a sectional view showing another embodiment. 1...Case, 2...Measuring tube, 3...Notch,
4... Fitting portion, 11... Gasket, 12... Earth ring, 12a... Mounting piece.

Claims (1)

[Scope of utility model registration request] A fitting portion having a notch is provided by extending the opening ends to both ends of the cylindrical case that houses the measuring tube, and an annular gasket is fitted to this fitting portion. An electromagnetic flowmeter characterized in that a thin plate-like earth ring is interposed between the measurement tubes, and a mounting piece protruding from the periphery of the earth ring faces the notch and is attached to the case.