CN204359368U - A kind of electromagnetic sensor of detachable electrode - Google Patents

Abstract

The utility model discloses an electromagnetic sensor with detachable electrodes, which comprises a flow tube, a lining, a magnetic yoke, an excitation coil, and a shell. A T-shaped piece is extended, and the T-shaped piece is implanted into the electrode cup. An electrode in a cross structure is arranged in the electrode cup. One end of the electrode penetrates the T-shaped piece until it reaches the lining, and the other end of the electrode is An insulating bushing is sheathed on the outer wall of a free end, and a spring is provided outside the insulating bushing. The electrode cup is provided with a threading hole on the cup wall inside the shell. The utility model adopts an external pressure electrode, and the part in contact with the medium is small in size, thereby reducing the degree of impact and wear of the medium on the electrode, and the closed detachable electrode design delays the progress of fouling on the electrode surface and prolongs the service life of the electrode.

Description

An Electromagnetic Sensor with Detachable Electrodes

technical field

The utility model relates to the technical field of electromagnetic sensors in electromagnetic flowmeters, in particular to an electromagnetic sensor with detachable electrodes.

Background technique

The electromagnetic flowmeter is designed based on Faraday's law of electromagnetic induction. The measuring tube of the flowmeter is a non-magnetic alloy tube lined with insulating material. Two electrodes pass through the tube wall along the tube diameter and are fixed on the tube. The excitation coil is pulsed. During excitation, a working magnetic field will be generated in the direction perpendicular to the measuring pipeline, as described in patent CN 201020655456.9.

Based on the continuous development of the measurement principle and technology of electromagnetic flowmeters, the technical characteristics of electromagnetic flowmeters, such as high measurement accuracy and no pressure loss, are widely used in the field of measurement and control of conductive liquids.

However, it can be concluded from the measurement principle that the part of the electromagnetic sensor in the electromagnetic flowmeter that contacts the medium mainly includes electrodes and linings. The lining materials mainly include PFA, PTFE, ceramics, and rubber. There are various schemes, but all have the following disadvantages:

1) The sensor is used for a long time, and the surface of the electrode is fouled, which makes the sensor unable to measure accurately. It can only be solved by disassembling the sensor and cleaning the electrode;

2) The medium is a liquid containing solid particles, such as pulp, mortar, mud and other slurries. The solid particles rub against the electrode for a long time, causing the electrode to wear and the sensor to be unusable, resulting in the need to replace the sensor.

Utility model content

The purpose of the utility model is to overcome the shortcomings of the existing electromagnetic sensor, such as the electrodes are easy to scale and easy to be worn by the medium, and provide a method to optimize the structure and installation method of the electrode, reduce the degree of the electrode being impacted and worn, and improve the electrode seal. The way and installation structure, so as to achieve the purpose of wear resistance of the electrode and the purpose of repeated replacement of the electromagnetic sensor with detachable electrodes.

In order to achieve the above purpose, the utility model is achieved through the following technical solutions: an electromagnetic sensor with detachable electrodes, including a flow tube and a lining sleeved therein, the outside of the flow tube is provided with a ring of magnetic yoke, An excitation coil is arranged inside the yoke, and the yoke is covered with a casing. It is characterized in that a pair of electrode cups that communicate with its inner cavity are arranged on the side wall of the flow tube, and each of the electrode cups The outer ends of the electrode cups pass through the outer shell, and each outer end of the electrode cup is covered with an end cover, and the liner is extended to the outside of the flow tube with a pair of T-shaped pieces, the T-shaped pieces and the liner An integral structure, each of the T-shaped pieces is respectively implanted into one of the electrode cups, and an electrode in a cross structure is arranged in each of the electrode cups, and one end of the electrode penetrates the T-shaped piece until In the lining, an insulating bushing is sheathed on the outer wall of the other free end of the electrode, and a spring is provided outside the insulating bushing, and the outer cover of the spring has a compression inner cover. The outer wall and the inner wall of the electrode cup are threadedly matched, an electrode lead lug is provided on the outer free end of the electrode, and a threading hole is provided on the cup wall of the electrode cup in the outer shell.

Preferably, the inner end surface of the electrode is flush with the inner diameter wall surface of the lining.

Preferably, an O-ring is arranged in the electrode cup between the electrode and the T-shaped piece.

Beneficial effects: (1) Since the electrode used in the utility model is an external pressure electrode, the size of the part in contact with the medium is small, and the inner end surface of the electrode is flush with the wall surface of the inner diameter of the lining, thereby reducing the degree of impact wear of the medium on the electrode and directly improving Improve the wear resistance of the electrode and prolong the service life of the electrode.

(2) Since the utility model adopts the design of heightening the electrode cup, there is an end cover on the electrode cup, and the installation structure of the electrode and the lead wire method of the electrode can be directly checked by removing the end cover, so that the disassembly and installation of the electrode can be realized, and the entire sensor can be extended The service life of the electrode is long, and the closed electrode design delays the progress of fouling on the electrode surface and prolongs the service life of the electrode.

(3) Since the double sealing method of the liner and the O-ring is adopted in the utility model, the electrode presses the O-ring and the liner to realize double sealing, and the compression deformation of the liner can be small, which not only realizes the requirement of disassembling the electrode for many times Possibility, and greatly improve the sealing effect, and ultimately delay the progress of fouling on the surface of the electrode and prolong the service life of the electrode.

(4) In addition, because the utility model adopts a heightened electrode cup design, the electrodes are effectively shielded and protected, which reduces the interference of electrical signals such as excitation coils or external power frequencies, improves the signal-to-noise ratio, and effectively improves measurement stability. sex.

Description of drawings

Fig. 1 is the structural representation of the utility model;

Fig. 2 is an enlarged view of the structure of the electrode, electrode cup and other parts in Fig. 1 .

In the figure: 1-flow tube, 2-liner, 3-electrode assembly, 4-magnetic yoke, 5-excitation coil, 6-shell, 21-T-shaped piece, 31-electrode, 32-electrode cup, 33-O type Sealing ring, 34-insulation bushing, 35-spring, 36-compression inner cover, 37-electrode lead lug, 38-threading hole, 39-end cover.

Detailed ways

In order to make the technical means, creative features and objectives of the utility model easy to understand, the utility model is further described below in conjunction with specific embodiments.

Embodiment: As shown in Fig. 1 and Fig. 2, an electromagnetic sensor with detachable electrodes includes a flow tube 1 and a lining 2 sleeved therein. An excitation coil 5 is arranged inside the yoke 4 , and a casing 6 is covered outside the yoke 4 .

A pair of electrode assemblies 3 are arranged on the side wall of the flow tube 1, and each electrode assembly 3 is provided with an electrode cup 32 that passes through the inner cavity of the flow tube 1, and the outer end of each electrode cup 32 passes through the outer shell 6, And each electrode cup 32 is covered with an end cap 39 on its outer end.

The liner 2 extends outward from the flow tube 1 and is provided with a pair of T-shaped pieces 21. The T-shaped pieces 21 and the liner 2 are integrally structured. Each T-shaped piece 21 is implanted into an electrode cup 32 respectively, and each electrode cup 32 has a An electrode 31 in a cross structure is provided, one end of the electrode 31 penetrates the T-shaped piece 21 to the inside of the lining 2 , and the inner end surface of the electrode 31 is flush with the inner diameter wall of the lining 2 . An insulating bushing 34 is sheathed on the outer wall of the other free end of the electrode 31, and a spring 35 is provided on the outer wall of the insulating bushing 34. The outer cover of the spring 35 has a compression inner cover 36, and the outer wall of the compression inner cover 36 is connected to the electrode cup 32. The inner wall is matched with threads, an electrode lead lug 37 is arranged on the outer free end of the electrode 31, and a threading hole 38 is arranged on the cup wall of the electrode cup 32 in the shell.

An O-ring 33 is arranged between the electrode 31 and the T-shaped piece 21 .

Practical: Two electrode cups are welded on both sides of the axis of the measuring tube. The outside of each electrode cup is welded with the shell. The lining is lined inside the flow tube and extends to the inside of the electrode cup. The extended part is named T-shaped piece.

1) Disassemble the electrode: loosen the end cover, fix the electrode lead wire, and press the inner cover in sequence; take out the spring, insulating bushing, electrode, and O-ring;

2) Install electrodes: install O-rings, electrodes, insulating bushings, and springs in sequence; tighten and compress the inner cover, fix electrode leads, and end covers.

The basic principles, main features and advantages of the present utility model have been shown and described above. Those skilled in the industry should understand that the utility model is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principle of the utility model. The utility model does not depart from the spirit and scope of the utility model There will also be various changes and improvements, and these changes and improvements all fall within the scope of the claimed utility model. The scope of protection required by the utility model is defined by the appended claims and their equivalents.

Claims (3)

1. An electromagnetic sensor with detachable electrodes, comprising a flow tube and a lining that is sleeved therein, the outside of the flow tube is provided with a circle of magnetic yoke, and an excitation coil is arranged in the magnetic yoke, and the magnetic yoke The outer shell is covered with a shell, and it is characterized in that a pair of electrode cups leading to its inner cavity are arranged on the side wall of the flow tube, and the outer end of each electrode cup passes out of the shell, and each The outer end of the electrode cup is covered with an end cover, and the liner is provided with a pair of T-shaped pieces extending outward from the flow tube. into one of the electrode cups, each electrode cup is provided with an electrode in a cross structure, one end of the electrode penetrates the T-shaped piece to the inside of the lining, and the other free end of the electrode is on the outer wall An insulating bush is sleeved, and a spring is provided outside the insulating bush. The outer cover of the spring has a compression inner cover. The outer wall of the compression inner cover is threadedly matched with the inner wall of the electrode cup. The electrode An electrode lead lug is arranged on the outer free end of the electrode cup, and a threading hole is arranged on the cup wall in the outer shell of the electrode cup. 2 . The electromagnetic sensor with detachable electrodes according to claim 1 , wherein the inner end surface of the electrode is flush with the inner diameter wall surface of the lining. 3 . 3. The electromagnetic sensor with detachable electrodes according to claim 1 or 2, characterized in that an O-ring is arranged between the electrodes and the T-shaped piece.