Flexible cable type magnetostriction liquid level transmitter

Abstract

The utility model provides a flexible cable type magnetostriction liquid level transmitter which comprises a gauge outfit assembly, a signal plate cavity assembly, a measuring core assembly arranged on the signal plate cavity assembly, a flexible cable assembly, a liquid level magnetic floater, an interface level magnetic floater and a heavy punch assembly, and the signal plate cavity assembly is arranged on one side of the gauge outfit assembly. A signal processing plate is arranged at the center of the top end in the core measuring assembly, a bracket is fixedly installed at the center of the core measuring assembly through bolts, the signal processing plate is fixed to one side of the top of the bracket through screws, a flexible cable assembly is arranged on one side of the bottom of the core measuring assembly, and a pagoda head is connected to one end of the bottom of the bracket. It is ensured that the insulation tube does not fall off during product assembly, flexible cable coiling and installation, and the situation that after the insulation tube falls off, the end portion clamps a waveguide wire to affect signals is avoided. The bottom of the waveguide wire is kept in a free state, and enough space is reserved, so that free stretching in the processes of assembly, coiling, installation and the like is facilitated, and the insulation tube is prevented from propping against the waveguide wire after thermal expansion and cold contraction.

Description

Technical Field

[0001] The utility model relates to the technical field related to magnetostrictive liquid level transmitters, in particular to a flexible cable type magnetostrictive liquid level transmitter. Background Art

[0002] When it is necessary to install a liquid level transmitter that outputs electrical signals on the top of the equipment, you can choose top-mounted magnetic float liquid level transmitter, magnetostrictive liquid level transmitter, radar level meter and other products. If you need to measure the liquid level and interface level at the same time, you usually choose a magnetostrictive liquid level transmitter, and the same product can output two signals. When the installation height is large or the top space is limited, the flexible cable magnetostrictive liquid level transmitter becomes the preferred product.

[0003] The magnetostrictive liquid level transmitter is mainly composed of a probe rod, a magnetic float and electronic components. A waveguide wire is installed in the probe rod. When the electric pulse generated by the electronic component is transmitted along the waveguide wire, the electric pulse is accompanied by a circular magnetic field perpendicular to the waveguide wire and transmitted along the waveguide wire at the speed of light. When the pulse circular magnetic field meets the inherent magnetic field of the magnetic float, the magnetic field vectors of the two are superimposed to form a spiral magnetic field, which generates instantaneous torque and forms a mechanical torque wave on the waveguide wire. It is transmitted back to the electronic component at the speed of sound, generating induced pulses at both ends of the coil. By measuring the time difference between the generated pulse and the induced pulse generated by the return of the torque wave, the measured liquid level can be accurately calculated.

[0004] Since the flexible cable of the flexible cable magnetostrictive liquid level transmitter is in a coiled state during transportation and installation, the waveguide wire will hit the inner wall of the probe rod. If the flexible cable cannot be straightened after installation, the wall hitting situation may still exist. In addition, if the product's coiling radius is too small, or a single point of force is applied during transportation, the waveguide wire may bend, resulting in signal weakening and unreliable measurement.

[0005] Existing soft cable magnetostrictive products basically adopt positioning measures, such as fixing the waveguide wire on the frame, or installing a circuit board at the bottom and welding the waveguide wire to the circuit board, or using a spring at the bottom to pull the measuring core to ensure that the waveguide wire is in a straight state.

[0006] The above structure has two disadvantages: on the one hand, the thermal expansion and contraction coefficient of the skeleton or insulating tube is usually inconsistent with that of the waveguide wire. When the temperature changes on site, the waveguide wire may bend and press against the skeleton or insulating tube, resulting in the inability to measure the liquid level below the contact point normally. On the other hand, the signal will be weakened after the waveguide wire is forcibly straightened. Even if the signal is amplified by electronic components, unreliable measurement is likely to occur. Therefore, this scheme specially proposes a soft cable magnetostrictive liquid level transmitter to solve the above problems. Utility Model Content

[0007] In order to overcome the defects of the prior art, the utility model provides a flexible cable type magnetostrictive liquid level transmitter.

[0008] To achieve the above-mentioned purpose, the technical solution of the utility model is implemented as follows: a flexible cable type magnetostrictive liquid level transmitter, comprising a meter head assembly, a signal plate cavity assembly, a measuring core assembly arranged in the signal plate cavity assembly, a flexible cable assembly, a liquid level magnetic float, a boundary position magnetic float and a weight assembly, the signal plate cavity assembly is arranged on one side of the meter head assembly, a signal processing board is arranged at the top center of the measuring core assembly, a bracket is fixedly installed at the center of the measuring core assembly by bolts, the signal processing board is fixed to the top side of the bracket by screws, the flexible cable assembly is arranged on the bottom side of the measuring core assembly, and the bottom of the bracket One end of the flexible cable assembly is connected to a pagoda head, and one side of the bottom of the pagoda head is connected to an insulating tube, a first threaded joint is arranged at the top of the outer periphery of the flexible cable assembly, the bottom end of the bracket is fixedly connected to the first threaded joint by a fixing screw, a hard tube is connected between the flexible cable assembly and the liquid level magnetic float, a waveguide wire is arranged at the center of the hard tube, one side of the bottom of the liquid level magnetic float is connected to the boundary position magnetic float, the bottom of the hard tube passes through the liquid level magnetic float and the boundary position magnetic float, the bottom end of the hard tube is located at one side of the bottom of the boundary position magnetic float and is provided with a second threaded joint, and a weight is connected to the hard tube through the second threaded joint.

[0009] Preferably, a wire mesh composite tube is provided at one end of the hard tube close to the liquid level magnetic float and the boundary position magnetic float, the corrugated tube external tube is welded on the outside of the wire mesh composite tube in the hard tube, and the corrugated tube internal tube is connected to the inner side of the top of the corrugated tube external tube in the hard tube.

[0010] Preferably, a return line is connected between the signal processing board and the flexible cable assembly in the core measuring assembly.

[0011] Preferably, the hard tube has a diameter of 20 mm, a thickness of 4 mm, and a length between 200 mm and 300 mm.

[0012] Preferably, the bottom end of the hard tube is filled with the rubber plug, and the return line is located on one side of the bottom of the rubber plug.

[0013] Preferably, the second threaded joint is connected to the weight via a fastener assembly, and a lifting ring assembly is provided on one side of the bottom of the weight.

[0014] Preferably, permanent magnets are disposed inside the liquid level magnetic float and the boundary position magnetic float.

[0015] The beneficial effects of the utility model are embodied in:

[0016] The utility model provides a second threaded joint at the bottom of the flexible cable for connecting a heavy hammer or connecting and fixing with a hook at the bottom of the tank, so as to ensure that the flexible cable is straightened after installation; a section of hard pipe is first processed at the top of the flexible cable near the coil position to ensure the signal stability at the near blind area position; the connection part between the flexible cable and the hard pipe adopts socket welding after tight fitting, and the joint is corrected before welding to ensure the concentricity of the flexible cable and the hard pipe; a pagoda head that is tightly matched with the size of the insulating tube is added to the bracket to ensure that the insulating tube will not fall off during product assembly, flexible cable coiling and installation, so as to avoid the end of the insulating tube being stuck to the waveguide wire and affecting the signal after it falls off; the bottom of the waveguide wire is kept in a free state and sufficient space is reserved, so as to facilitate free expansion and contraction during assembly, coiling and installation, and prevent the insulating tube from supporting the waveguide wire after thermal expansion and contraction; the waveguide wire cavity is filled with nitrogen to seal; the electronic component junction box is led out from the side of the cavity, and the connection with the cavity is sealed with AB glue, so as to avoid moisture entering the waveguide wire cavity and causing rust of the waveguide wire, thereby improving the service life of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In the attached picture:

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0019] Figure 2 It is a schematic diagram of the top structure of the overall structure of the utility model;

[0020] Figure 3 It is a schematic diagram of the bottom structure of the overall structure of the utility model.

[0021] Description of reference numerals:

[0022] 1. Meter head assembly; 2. Signal board cavity assembly; 3. Measuring core assembly; 4. Flexible cable assembly; 5. Liquid level magnetic float; 6. Interface magnetic float; 7. Weight assembly; 8. Signal processing board; 9. Bracket; 10. Return line; 11. Fixing screw; 12. First threaded joint; 13. Hard pipe; 14. Corrugated pipe internal pipe; 15. Corrugated pipe external pipe; 16. Pagoda head; 17. Insulating pipe; 19. Wire mesh composite pipe; 20. Rubber plug; 21. Weight; 22. Second threaded joint; 23. Fastener assembly; 24. Lifting ring assembly. DETAILED DESCRIPTION

[0023] The utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] It should be noted that if the utility model embodiments involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0025] In addition, "multiple" means more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0026] Example: Figure 1 , Figure 2 and Figure 3 As shown: it includes a header assembly 1, a signal board cavity assembly 2, a measuring core assembly 3 arranged in the signal board cavity assembly 2, a soft cable assembly 4, a liquid level magnetic float 5, a boundary position magnetic float 6 and a heavy hammer assembly 7. The signal board cavity assembly 2 is arranged on one side of the header assembly 1, and the header assembly 1 includes a junction box shell, a surge protection terminal board, a conversion module, etc., which receives the sensor signal from the measuring core, converts it into a standard DC signal output, and provides LCD display and communication functions. The signal board cavity assembly 2 includes welding parts of the junction box connector and the cavity tube, as well as a plug, an O-ring, etc. AB glue is poured in the junction box connector to isolate moisture from the header assembly; a signal processing board 8 is arranged at the center of the inner top of the measuring core assembly 3, which is used to emit electric pulses, detect the torque wave returned by the waveguide wire, sense the change of the external magnetic field position, and convert it into an electric signal for processing by the conversion module, and a bracket 9 is fixedly installed at the center of the measuring core assembly 3 by bolts, and the signal processing board 8 is fixed to the top of the bracket 9 by screws. On the side, a flexible cable assembly 4 is arranged on one side of the bottom of the measuring core assembly 3. The flexible cable assembly 4 includes a threaded joint, a stainless steel flexible cable, a heavy hammer joint, etc., which serves as a protection for the measuring core assembly and also provides an interface for the mounting flange and the heavy hammer. A pagoda head 16 is connected to one end of the bottom of the bracket 9, and an insulating tube 17 is connected to one side of the bottom of the pagoda head 16. A first threaded joint 12 is arranged at the top of the outer periphery of the flexible cable assembly 4. The bottom end of the bracket 9 is fixedly connected to the first threaded joint 12 by a fixing screw 11. A hard tube 13 is connected between the cable assembly 4 and the liquid level magnetic float 5. A waveguide wire 18 is arranged at the center of the hard tube 13, which can sense the position of the magnetic float through the magnetostrictive effect, thereby measuring the liquid level. The bottom side of the liquid level magnetic float 5 is connected to the boundary magnetic float 6. The bottom of the hard tube 13 passes through the liquid level magnetic float 5 and the boundary magnetic float 6. The bottom end of the hard tube 13 is located at the bottom side of the boundary magnetic float 6 and is provided with a second threaded joint 22. A weight 21 is connected to the hard tube 13 through the second threaded joint 22.

[0027] See also Figure 2 A wire mesh composite tube 19 is provided at one end of the hard tube 13 close to the liquid level magnetic float 5 and the boundary magnetic float 6, a bellows external tube 15 is welded on the outside of the wire mesh composite tube 19 in the hard tube 13, and a bellows internal tube 14 is connected to the inner side of the top of the bellows external tube 15 in the hard tube 13.

[0028] See also Figure 1 In the measuring core assembly 3, a return line 10 is connected between the signal processing board 8 and the soft cable assembly 4 for closing the circuit. Permanent magnets are arranged inside the liquid level magnetic float 5 and the boundary position magnetic float 6. The liquid level magnetic float has a built-in permanent magnet and always floats on the surface of the upper medium to detect changes in the upper liquid level. The boundary position magnetic float has a built-in permanent magnet and floats on the interface between the upper medium and the lower medium to detect the height of the lower liquid level.

[0029] See also Figure 1 and Figure 3 The hard tube 13 has a diameter of 20 mm, a thickness of 4 mm, and a length between 200 mm and 300 mm. The bottom end of the hard tube 13 is filled with a rubber plug 20. The return line 10 is located on one side of the bottom of the rubber plug 20 to prevent moisture from the bottom and to position the return line. The second threaded joint 22 is connected to a weight 21 through a fastener assembly 23, and a lifting ring assembly 24 is provided on one side of the bottom of the weight 21 to anchor the weight on a hook at the bottom of the tank.

[0030] When in use, the lifting ring assembly 24 applies voltage to the loop formed by the waveguide wire 18 and the return line 10, and current is generated on the waveguide wire 18, forming a circular magnetic field around it. When the circular magnetic field is coupled with the biased permanent magnetic field of the liquid level magnetic float 5 and the boundary position magnetic float 6, a Widman effect torsional stress wave is formed on the surface of the waveguide wire 18. The torsional wave propagates from the generating point to the waveguide wire at the speed of sound, senses the change of the external magnetic field position in the measuring core assembly 3, and converts it into an electrical signal for processing by the conversion module. The sensing signal from the measuring core is received through the header assembly 1, converted into a standard DC signal output, and provides LCD display and communication functions.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A flexible cable type magnetostrictive liquid level transmitter, comprising a meter head assembly (1), a signal plate cavity assembly (2), a measuring core assembly (3) arranged in the signal plate cavity assembly (2), a flexible cable assembly (4), a liquid level magnetic float (5), an interface magnetic float (6) and a weight assembly (7), characterized in that: The signal board cavity assembly (2) is arranged on one side of the meter head assembly (1); a signal processing board (8) is arranged at the center of the inner top of the measuring core assembly (3); a bracket (9) is fixedly installed at the center of the measuring core assembly (3) by bolts; the signal processing board (8) is fixed to the top side of the bracket (9) by screws; the soft cable assembly (4) is arranged on the bottom side of the measuring core assembly (3); a pagoda head (16) is connected to one end of the bottom of the bracket (9); and an insulating tube (17) is connected to one side of the bottom of the pagoda head (16); a first threaded joint (12) is arranged at the top of the outer periphery of the soft cable assembly (4); the bracket (9) ) is fixedly connected to the first threaded joint (12) by a fixing screw (11); a hard tube (13) is connected between the soft cable assembly (4) and the liquid level magnetic float (5); a waveguide wire (18) is arranged at the center of the hard tube (13); the bottom side of the liquid level magnetic float (5) is connected to the boundary magnetic float (6); the bottom of the hard tube (13) passes through the liquid level magnetic float (5) and the boundary magnetic float (6); the bottom end of the hard tube (13) is located on the bottom side of the boundary magnetic float (6) and is provided with a second threaded joint (22); a weight (21) is connected to the hard tube (13) via the second threaded joint (22).

2. A flexible cable type magnetostrictive liquid level transmitter according to claim 1, characterized in that: A wire mesh composite tube (19) is provided at one end of the hard tube (13) close to the liquid level magnetic float (5) and the boundary position magnetic float (6); a bellows outer tube (15) is welded to the outside of the wire mesh composite tube (19) in the hard tube (13); and a bellows inner tube (14) is connected to the inner side of the top of the bellows outer tube (15) in the hard tube (13).

3. The flexible cable type magnetostrictive liquid level transmitter according to claim 1, characterized in that: A return line (10) is connected between the signal processing board (8) and the flexible cable assembly (4) in the measuring core assembly (3).

4. The flexible cable type magnetostrictive liquid level transmitter according to claim 1, characterized in that: The hard tube (13) has a diameter of 20 mm, a thickness of 4 mm, and a length between 200 mm and 300 mm.

5. The flexible cable type magnetostrictive liquid level transmitter according to claim 3, characterized in that: The bottom end of the hard tube (13) is filled with a rubber plug (20), and the return line (10) is located on one side of the bottom of the rubber plug (20).

6. The flexible cable type magnetostrictive liquid level transmitter according to claim 1, characterized in that: The second threaded joint (22) is connected to the weight (21) via a fastener assembly (23), and a lifting ring assembly (24) is provided on one side of the bottom of the weight (21).

7. The flexible cable type magnetostrictive liquid level transmitter according to claim 1, characterized in that: The liquid level magnetic float (5) and the boundary position magnetic float (6) are both provided with permanent magnetic steel inside.

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