阅读说明：本技术 一种低温液位测量装置 (Low-temperature liquid level measuring device ) 是由 李培勇 张志乾 程东芹 高沪光 刘琦 周彤 于 2021-09-07 设计创作，主要内容包括：本发明公开了一种超低温液位测量装置,用于超低温液体盛放于超低温液体容器(4)内,包括下部插入超低温液体内且固定的超导丝(2)、缠绕于所述超导丝(2)上端的加热丝(1)、与所述加热丝(1)与超导丝(2)的串联点连接的电压正极引线、与所述加热丝(1)的另一端连接的电流正极引线、与所述超导丝(2)的下端分别连接的电压负极引线和电流负极引线,所述电流正极引线和电流负极引线之间通入恒定电流,所述电压负极引线和电流负极引线之间连接电压表。该超低温液位测量装置的引出线较少,接线简单,漏热小,接线及控制简单准确。(The invention discloses an ultralow temperature liquid level measuring device, which is used for holding ultralow temperature liquid in an ultralow temperature liquid container (4) and comprises a superconducting wire (2) with the lower part inserted into the ultralow temperature liquid and fixed, a heating wire (1) wound on the upper end of the superconducting wire (2), a voltage positive lead connected with the series point of the heating wire (1) and the superconducting wire (2), a current positive lead connected with the other end of the heating wire (1), and a voltage negative lead and a current negative lead respectively connected with the lower end of the superconducting wire (2), wherein constant current is introduced between the current positive lead and the current negative lead, and a voltmeter is connected between the voltage negative lead and the current negative lead. The ultralow temperature liquid level measuring device has the advantages of fewer outgoing lines, simple wiring, small heat leakage and simple and accurate wiring and control.)

1. The utility model provides an ultra-low temperature liquid level measurement device, its characterized in that for ultra-low temperature liquid is held in ultra-low temperature liquid container (4), insert in ultra-low temperature liquid and fixed superconducting wire (2), twine in heater strip (1) of superconducting wire (2) upper end, with the voltage positive lead wire that heater strip (1) and the series connection point of superconducting wire (2) are connected, with the current positive lead wire that the other end of heater strip (1) is connected, with voltage negative lead wire and the current negative lead wire that the lower extreme of superconducting wire (2) is connected respectively, let in constant current between current positive lead wire and the current negative lead wire, connect the voltmeter between voltage negative lead wire and the current negative lead wire.

2. An ultra-low temperature liquid level measuring device as claimed in claim 1, further comprising a protective sleeve (3) placed in the ultra-low temperature liquid container (4), the protective sleeve (3) having a plurality of through holes thereon, the superconducting wire (2), the heating wire (1), the voltage positive lead, the current positive lead, the voltage negative lead and the current negative lead being placed in the protective sleeve (3).

3. Ultra-low temperature liquid level measuring device according to claim 2, characterized in that the protective sleeve (3) is a teflon sleeve.

4. Ultra-low temperature liquid level measuring device according to claim 2, characterized in that the through holes on the protective sleeve (3) are arranged in bilateral symmetry.

5. An ultra-low temperature liquid level measuring device as claimed in any one of claims 2 to 4, further comprising a non-magnetic tension spring (5), wherein the bottom of the superconducting wire (2) is connected with the bottom of the protective sleeve (3) through the tension spring (5).

6. An ultra-low temperature liquid level measuring device as claimed in claim 5, wherein the tension spring (5) is made of stainless steel.

7. The ultra-low temperature liquid level measuring device according to any one of claims 1 to 4, wherein the heating wire (1) is wound around the superconducting wire (2) with a length of 0.055 to 0.08 of the total length of the superconducting wire (2).

8. The ultra-low temperature liquid level measuring device of any one of claims 1 to 4, wherein the voltage positive lead, the current positive lead, the voltage negative lead and the current negative lead are all copper wires.

Technical Field

The invention relates to the technical field of liquid level meters, in particular to an ultralow-temperature liquid level measuring device.

Background

In order to accurately measure the liquid level height in the ultralow temperature environment, the liquid level height of the liquid helium is measured by utilizing the relation between the superconducting state and the non-superconducting state of the superconducting wire. Superconducting refers to a phenomenon in which the resistance of a conductor suddenly becomes zero under a certain temperature condition, and is classified into high-temperature superconducting and low-temperature superconducting.

The currently used liquid level meter comprises a sleeve, a heater and a measuring device, wherein the heater and the measuring device are mutually independent, and up to 6 lead wires comprise a current positive lead end, a current negative lead end, a voltage positive lead end, a voltage negative lead end, a heater positive lead end and a heater negative lead end. Lead to more lead-out wires, the wiring is complicated, need two sets of systems of control heater and measuring device simultaneously, control is loaded down with trivial details to because the lead-out wire is more leads to the possibility increase of leaking heat.

In summary, how to effectively solve the problems of more outgoing lines, increased heat leakage and the like caused by mutual independence of the heating part and the measuring part in the prior art is a problem which needs to be solved urgently by technical personnel in the field at present.

Disclosure of Invention

The invention aims to provide an ultralow temperature liquid level measuring device which has fewer outgoing lines, small heat leakage and simple and accurate wiring and control.

In order to solve the technical problems, the invention provides the following technical scheme:

the utility model provides an ultra-low temperature liquid level measurement device for ultra-low temperature liquid is held in ultra-low temperature liquid container, insert ultra-low temperature liquid in and fixed superconducting filament, twine in including the lower part the heater strip of superconducting filament upper end, with the voltage positive lead wire that the series connection point of heater strip and superconducting filament is connected, with the current positive lead wire that the other end of heater strip is connected, with voltage negative lead wire and current negative lead wire that the lower extreme of superconducting filament is connected respectively, let in constant current between current positive lead wire and the current negative lead wire, connect the voltmeter between voltage negative lead wire and the current negative lead wire.

Preferably, the protection sleeve is placed in the ultralow-temperature liquid container, the protection sleeve is provided with a plurality of through holes, and the superconducting wire, the heating wire, the voltage positive lead, the current positive lead, the voltage negative lead and the current negative lead are placed in the protection sleeve.

Preferably, the protective sleeve is a teflon sleeve.

Preferably, the through holes on the protective sleeve are arranged in bilateral symmetry.

Preferably, the device also comprises a nonmagnetic tension spring, and the bottom of the superconducting wire is connected with the bottom of the protective sleeve through the tension spring.

Preferably, the material of extension spring is stainless steel.

Preferably, the heating wire is wound on the superconducting wire, and the length of the heating wire accounts for 0.055-0.08 of the total length of the superconducting wire.

Preferably, the voltage positive lead, the current positive lead, the voltage negative lead and the current negative lead are all copper wires.

The ultralow temperature liquid level measuring device provided by the invention comprises a superconducting wire, a heating wire, a voltage anode lead, a current anode lead, a voltage cathode lead and a current cathode lead, wherein ultralow temperature liquid is contained in an ultralow temperature liquid container. The lower part of the superconducting wire is inserted into and fixed in the ultralow temperature liquid, namely the lower part of the superconducting wire is immersed in the ultralow temperature liquid, the upper part of the superconducting wire is immersed in the ultralow temperature cold air but not in the ultralow temperature liquid, and the resistance of the superconducting wire is zero in the ultralow temperature liquid environment.

The heating wire is wound at the upper end of the superconducting wire, current flows through the heating wire, the heating wire generates heat, and the temperature of the superconducting wire part wound with the heating wire is higher, so that the superconducting wire which is not soaked in the ultra-low temperature liquid in the ultra-low temperature cold air is changed into a non-superconducting state.

And a voltage anode lead is connected with the series connection point of the heating wire and the superconducting wire, and a voltage anode lead end is led out from the upper end of the voltage anode lead. And the current positive lead is connected with the other end of the heating wire, and a current positive lead end is led out. And the voltage negative lead and the current negative lead are respectively connected with the lower end of the superconducting wire, and a voltage negative lead end and a current negative lead end are respectively led out.

Constant current is introduced between the current anode lead and the current cathode lead, a voltmeter is connected between the voltage cathode lead and the current cathode lead, and a voltage value between the voltage anode lead end and the voltage cathode lead end is measured.

When the ultralow-temperature liquid level measuring device is soaked in ultralow-temperature liquid, constant current is introduced into a current anode lead end and a current cathode lead end, the current flows through the heating wires, the heating wires generate heat, the temperature of the superconducting wire part wound around the heating wires is higher, the superconducting wire part is in a non-superconducting state, the superconducting wire part stops when the superconducting wire part extends downwards to the liquid level in the non-superconducting state, and the liquid level height is obtained through calculation.

The ultra-low temperature liquid level measuring device provided by the invention utilizes the superconducting characteristic that the resistance of the superconducting wire is zero under a certain temperature environment, the superconducting wire which is immersed in ultra-low temperature liquid but in ultra-low temperature cold air is changed into a non-superconducting state by heating the heating wire, and the voltage value of the superconducting wire above the liquid level of the liquid level meter is measured by constant current. The ultralow temperature liquid level measuring device has the advantages of fewer outgoing lines, simple wiring, small heat leakage and simple and accurate wiring and control.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an ultra-low temperature liquid level measuring device provided in an embodiment of the present invention.

The drawings are numbered as follows:

heating wire 1, superconducting wire 2, protective sleeve 3, ultralow temperature liquid container 4, extension spring 5.

Detailed Description

The core of the invention is to provide an ultralow temperature liquid level measuring device which has fewer outgoing lines, small heat leakage and simple and accurate wiring and control.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an ultra-low temperature liquid level measuring device according to an embodiment of the present invention.

In a specific embodiment, the ultralow temperature liquid level measuring device provided by the invention is used for holding ultralow temperature liquid in an ultralow temperature liquid container 4, and comprises a superconducting wire 2, a heating wire 1 wound on the upper end of the superconducting wire 2, a voltage positive lead connected with the series point of the heating wire 1 and the superconducting wire 2, a current positive lead connected with the other end of the heating wire 1, and a voltage negative lead and a current negative lead respectively connected with the lower end of the superconducting wire 2, wherein constant current is introduced between the current positive lead and the current negative lead, and a voltmeter is connected between the voltage negative lead and the current negative lead.

In the above-mentioned structure, ultra-low temperature liquid level measurement device includes superconducting filament 2, heater strip 1, the anodal lead wire of voltage, the anodal lead wire of electric current, voltage negative pole lead wire and electric current negative pole lead wire, and ultra-low temperature liquid is held in ultra-low temperature liquid container 4. The lower part of the superconducting wire 2 is inserted into and fixed in the ultralow temperature liquid, namely the lower part of the superconducting wire 2 is immersed in the ultralow temperature liquid, the upper part of the superconducting wire 2 is in ultralow temperature cold air but not in the ultralow temperature liquid, and the resistance of the superconducting wire 2 is zero in the ultralow temperature liquid environment.

The heating wire 1 is wound at the upper end of the superconducting wire 2, current flows through the heating wire 1, the heating wire 1 generates heat, and the temperature of the superconducting wire 2 wound around the heating wire 1 is higher, so that the superconducting wire 2 which is in ultralow-temperature cold air but not soaked in ultralow-temperature liquid is changed into a non-superconducting state.

And a voltage anode lead is connected with the series connection point of the heating wire 1 and the superconducting wire 2, and a voltage anode lead end V + is led out from the upper end of the voltage anode lead. The current anode lead is connected with the other end of the heating wire 1, and the current anode lead end I + is led out. The voltage negative lead and the current negative lead are respectively connected with the lower end of the superconducting wire 2, and a voltage negative lead end V-and a current negative lead end I-are respectively led out.

Constant current is introduced between the current anode lead and the current cathode lead, a voltmeter is connected between the voltage cathode lead and the current cathode lead, and the voltage value between the voltage anode lead end V + and the voltage cathode lead end V-is measured.

Specifically, when the ultralow-temperature liquid level measuring device is soaked in ultralow-temperature liquid, constant current is introduced to a current anode lead end and a current cathode lead end, the current flows through the heating wire 1, the heating wire 1 generates heat, the temperature of the superconducting wire 2 wound around the heating wire 1 is higher, the superconducting wire is in a non-superconducting state, the superconducting state stops when the superconducting wire extends downwards to the liquid level, and the liquid level height is obtained through calculation.

The estimation process is as follows:

firstly, measuring the constant current I introduced into the superconducting wire 2 in a non-superconducting state in ultralow-temperature cold air, measuring the voltage U at two ends of the superconducting wire 2 in the non-superconducting state, and calculating to obtain the total resistance R = U/I of the superconducting wire 2 in cold helium;

assuming that the length of the superconducting wire 2 is L, the length of the superconducting wire 2 below the liquid surface is L₁The length of the superconducting wire 2 above the liquid surface is L₂The height ratio of the liquid level is H = L₁/L*100%；

When liquid helium is in the measuring range of the liquid level meter, constant current I is introduced, and the voltage corresponding to the superconducting wire 2 above the liquid level of the liquid helium is measured to be U₂The resistance of the superconducting wire 2 above the liquid surface is R₂；

Obtaining U according to the proportional relation₂/U=R₂/R=L₂/L，L2=L*U₂/U，L1=L-L₂=L(1-U₂/U), from H = L₁The ratio of liquid level to height H = (1-U) is obtained by/L100%₂/U)*100%。

The ultra-low temperature liquid level measuring device provided by the invention utilizes the superconducting characteristic that the resistance of the superconducting wire 2 is zero under a certain temperature environment, the superconducting wire 2 which is in ultra-low temperature cold air but not soaked in ultra-low temperature liquid is changed into a non-superconducting state by heating the heating wire 1, and the voltage value of the superconducting wire 2 above the liquid level of the liquid level meter is measured by constant current. The ultralow temperature liquid level measuring device has the advantages of fewer outgoing lines, simple wiring, small heat leakage and simple and accurate wiring and control.

The ultralow temperature liquid level measuring device is only a preferred scheme, is particularly not limited to the optimal scheme, can be adjusted in a targeted manner according to actual needs on the basis, so that different implementation modes can be obtained, and further comprises a protective sleeve 3 placed in the ultralow temperature liquid container 4, wherein the protective sleeve 3 is provided with a plurality of through holes, so that the ultralow temperature liquid can conveniently circulate, the ultralow temperature liquid inside and outside the protective sleeve 3 can be kept the same, and the accurate liquid level measurement can be ensured.

The protection sleeve 3 has good low-temperature characteristic and can be bent into a required shape, the superconducting wire 2, the heating wire 1, the voltage anode lead, the current anode lead, the voltage cathode lead and the current cathode lead are arranged in the protection sleeve 3, the superconducting wire 2, the heating wire 1, the voltage anode lead, the current anode lead, the voltage cathode lead and the current cathode lead are integrated together by the protection sleeve 3, the superconducting wire 2, the heating wire 1, the voltage anode lead, the current anode lead, the voltage cathode lead and the current cathode lead are taken and placed simultaneously through the protection sleeve 3, the superconducting wire 2, the heating wire 1, the voltage anode lead, the current anode lead, the voltage cathode lead and the current cathode lead are protected, the floating of the superconducting wire 2 in ultralow-temperature liquid can be reduced, and the accuracy of liquid level measurement is ensured.

On the basis of the above embodiments, the protective sleeve 3 may be an insulating sleeve with good low-temperature characteristics, for example, the protective sleeve 3 may be a teflon sleeve with good low-temperature characteristics; the flexible deformation can change the shape according to the shapes of the superconducting wire 2, the heating wire 1, the voltage anode lead, the current anode lead, the voltage cathode lead, the current cathode lead and the ultralow temperature liquid container 4, and the use is convenient.

On the basis of the above specific embodiments, the through holes on the protection sleeve 3 are arranged in bilateral symmetry, that is, the left and right through holes are aligned, so that the liquid circulation is facilitated.

In another more reliable embodiment, on the basis of any one of the above embodiments, the device further comprises a nonmagnetic tension spring 5, and preferably, the tension spring 5 is made of stainless steel, so that the test result is not affected, and the measurement accuracy is ensured. The bottom of the superconducting wire 2 is connected with the bottom of the protective sleeve 3 through the tension spring 5, and the tension spring 5 enables the ultralow-temperature liquid level measuring device to effectively protect the superconducting wire 2 from being broken when the ultralow-temperature liquid level measuring device is bent, so that the measurement is accurate.

In another more reliable embodiment, on the basis of any one of the above embodiments, the length of the heating wire 1 wound around the superconducting wire 2 is 0.055-0.08 of the total length of the superconducting wire 2, for example, the total length of the superconducting wire 2 is 100cm, and the length of the heating wire 1 wound around the superconducting wire 2 is 5.5cm-8cm, so as to ensure the heating power of the heating wire 1. Preferably, the heating wire 1 is a constantan wire with stable resistance characteristics, the heating wire 1 is connected in series with the top end of the superconducting wire 2 and is uniformly wound on the top end of the superconducting wire 2, and the heating wire 1 is uniformly heated.

In another more reliable embodiment, on the basis of any one of the above embodiments, the voltage positive lead, the current positive lead, the voltage negative lead and the current negative lead are all copper wires, so that the conductivity is better, and the cost is lower.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The ultra-low temperature liquid level measuring device provided by the invention is described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.