阅读说明：本技术 一种液体火箭低温连接器表面涂层工艺及低温连接器 (Surface coating process for low-temperature connector of liquid rocket and low-temperature connector ) 是由 赵立乔 辛健 陈腾 张亚民 韩宏茵 张信波 符亮 高珠珠 于 2021-07-27 设计创作，主要内容包括：本发明公开了一种液体火箭低温连接器表面涂层工艺及低温连接器。喷涂工艺包括：第一、提供低温连接器,对低温连接器表面进行洁净处理；第二、将特氟龙原料均匀喷涂在低温连接器的表面；第三、对低温连接器高温加热,使得熔融状态下的特氟龙原料与低温连接器粘接。与现有技术相比,该工艺具有设计合理,结构稳定,加注低温推进剂完毕后可方便连接器脱落等优点,有效的避免了低温推进剂导致的结冰现象,提高了连接器脱落的可靠性。(The invention discloses a surface coating process of a low-temperature connector of a liquid rocket and the low-temperature connector. The spraying process comprises the following steps: firstly, providing a low-temperature connector, and cleaning the surface of the low-temperature connector; secondly, uniformly spraying a Teflon raw material on the surface of the low-temperature connector; thirdly, heating the low-temperature connector at high temperature to enable the Teflon raw material in a molten state to be bonded with the low-temperature connector. Compared with the prior art, the process has the advantages of reasonable design, stable structure, convenience in falling off of the connector after the low-temperature propellant is filled, and the like, effectively avoids the icing phenomenon caused by the low-temperature propellant, and improves the falling reliability of the connector.)

1. A surface coating process for a low-temperature connector of a liquid rocket is characterized in that,

providing a low-temperature connector, and cleaning the surface of the low-temperature connector;

uniformly spraying a Teflon raw material on the surface of the low-temperature connector;

and heating the low-temperature connector at a high temperature to bond the Teflon raw material in a molten state with the low-temperature connector.

2. The process for teflon coating of a surface of a liquid rocket cryogenic connector according to claim 1 wherein the cleaning of the surface of the cryogenic connector comprises cleaning the surface of the cryogenic connector with an organic solvent.

3. The process for coating the surface of a low-temperature connector of a liquid rocket according to claim 2, wherein the cleaning of the surface of the low-temperature connector with an organic solvent comprises: heating the low-temperature connector to volatilize the organic solvent on the surface of the low-temperature connector, wherein the temperature for heating the low-temperature connector to volatilize the organic solvent on the surface of the low-temperature connector is A, and A is more than or equal to 300 degrees and less than or equal to 400 degrees.

4. The process for coating the surface of a low-temperature connector of a liquid rocket according to claim 1, wherein the step of uniformly spraying the teflon raw material on the surface of the spraying part of the low-temperature connector further comprises the following steps: the surface-sprayed portion of the low-temperature connector is subjected to sand blasting to roughen the surface thereof.

5. The liquid rocket cryogenic connector surface coating process of claim 4, wherein the step of sand blasting the surface spraying part of the cryogenic connector to roughen the surface comprises the following specific steps: preparing 40-70 mesh quartz sand and 170-180 mesh brown corundum according to the proportion of 2:1, spraying the quartz sand and the brown corundum to the spraying part of the low-temperature connector by using high-pressure gas to assist in spraying the quartz sand and the brown corundum to the spraying part of the low-temperature connector, enabling the surface roughness (Ra) of the low-temperature connector to reach 2.0-3.5 mu m, and cleaning the surface of the low-temperature connector.

6. The surface coating process of a liquid rocket cryogenic connector according to claim 1, wherein the uniform spraying of Teflon material on the surface of the cryogenic connector spray site can be any one of a wet method and a dry method,

the wet method is to spray the Teflon dispersion liquid raw material on the surface of the part of the low-temperature connector needing to be sprayed by a spray gun;

in the dry method, powdery Teflon raw material is blown out of the trap by high-pressure gas to form uniform cloud-shaped spray, so that the spray is attached to the surface of the part of the low-temperature connector to be sprayed.

7. The surface coating process of a liquid rocket low-temperature connector according to claim 6, wherein the thickness of the coating sprayed on the spraying part of the low-temperature connector is B, and B is more than or equal to 5 μm and less than or equal to 200 μm.

8. The liquid rocket cryogenic connector surface coating process of claim 6, further comprising, after using the wet process: and heating the low-temperature connector sprayed with the wet Teflon coating in a baking furnace, wherein the heating temperature is C, C is more than or equal to 60 ℃ and less than or equal to 100 ℃, the heating time is T, and T is more than or equal to 2h and less than or equal to 4 h.

9. The process for coating the surface of a low-temperature connector of a liquid rocket according to claim 1, wherein the high-temperature heating temperature for bonding the teflon raw material and the low-temperature connector in a molten state is D, wherein D is more than or equal to 360 ℃ and less than or equal to 400 ℃.

10. A low-temperature connector is characterized by comprising an arrow-mounted interface structure and a ground interface structure, wherein the ground interface structure comprises a first connecting body and a locking structure arranged on the first connecting body, two ends of the locking structure are respectively connected with the arrow-mounted interface structure and the first connecting body, the arrow-mounted interface structure is used for being connected with a pipeline on an arrow, the first connecting body is used for being connected with a ground pipeline so as to ensure that a low-temperature propellant medium on the ground is conveyed onto the arrow, and the arrow-mounted interface structure is characterized in that the ground interface structure comprises a first connecting body and a locking structure arranged on the first connecting body,

the locking structure comprises a clamping jaw, a pin shaft and a pressing ring, the pressing ring is sleeved at one end of the first connecting body close to the arrow upper interface structure, the pin shaft penetrates through the pressing ring and the clamping jaw, the clamping jaw is configured to freely rotate along the surface of the pin shaft so as to control the arrow upper interface structure to be locked/separated with/from the first connecting body,

the surfaces of the joint ends of the arrow upper interface structure and the first connecting body, and the clamping jaws and the pressure rings are respectively provided with a Teflon coating, and the Teflon coatings are tightly attached to the surfaces of the arrow upper interface structure, the ground interface structure, the clamping jaws and the pressure rings;

the Teflon coating is used for reducing icing at the joint of the rocket interface structure and the first connecting body, so that after the coolant in the rocket is filled, the rocket interface structure is safely separated from the ground interface structure.

Technical Field

The invention relates to the field of liquid rockets, in particular to a surface coating process of a low-temperature connector of a liquid rocket and the low-temperature connector.

Background

With the rapid development of the aerospace industry, all the technologies related to the rocket field also realize the rapid advance. Rockets are currently the primary vehicles for launching satellites into space, and therefore, the continued reduction of rocket manufacturing and launch costs is a pursuit goal of large commercial space companies.

The low-temperature propellant filling and discharging connector is used for conveying liquid propellant media such as liquid hydrogen, liquid oxygen and liquid methane to the rocket, and can realize the functions of connecting, sealing, dropping and the like of the connector and a rocket liquid path interface. Because the liquid rocket adopts the low-temperature propellant, the low-temperature propellant medium in the channel can cause the combination part of the connector and the rocket liquid path interface to frost and freeze when in use, and particularly when the low-temperature propellant is filled, the normal falling of the connector can be influenced by the excessively thick ice layer of the combination part of the connector and the rocket liquid path interface, thereby influencing the rocket testing and launching process.

Therefore, how to provide a reasonable in design, stable in structure, after filling the low temperature propellant, can make things convenient for the connector to drop, is the problem that will solve at present.

Disclosure of Invention

The invention aims to provide a surface coating process of a low-temperature connector of a liquid rocket and the low-temperature connector, which have the advantages of reasonable design, stable structure, convenience in falling off of the connector after the low-temperature propellant is filled, and the like.

In order to achieve the purpose, the invention provides the following technical scheme:

a surface coating process for a low-temperature connector of a liquid rocket mainly comprises the following steps:

providing a low-temperature connector, and cleaning the surface of the low-temperature connector;

uniformly spraying a Teflon raw material on the surface of the low-temperature connector;

and heating the low-temperature connector at a high temperature to bond the Teflon raw material in a molten state with the low-temperature connector.

In the same embodiment, the cleaning of the surface of the low-temperature connector includes cleaning the surface of the low-temperature connector with an organic solvent.

In the same embodiment, the cleaning of the surface of the low-temperature connector by the organic solvent comprises: heating the low-temperature connector to volatilize the organic solvent on the surface of the low-temperature connector; and heating the low-temperature connector to ensure that the temperature for volatilizing the organic solvent on the surface of the low-temperature connector is A, wherein A is more than or equal to 300 ℃ and less than or equal to 400 ℃.

In the same embodiment, the step of uniformly spraying the teflon raw material on the surface of the spraying part of the low-temperature connector further comprises the following steps: the surface-sprayed portion of the low-temperature connector is subjected to sand blasting to roughen the surface thereof.

In the same embodiment, the sandblasting the surface-sprayed part of the low-temperature connector to roughen the surface thereof is specifically: preparing 40-70 mesh quartz sand and 170-180 mesh brown corundum according to the proportion of 2:1, spraying the quartz sand and the brown corundum to the spraying part of the low-temperature connector by using high-pressure gas to assist in spraying the quartz sand and the brown corundum to the spraying part of the low-temperature connector, enabling the surface roughness (Ra) of the low-temperature connector to reach 2.0-3.5 mu m, and cleaning the surface of the low-temperature connector.

In the same embodiment, the surface of the teflon raw material uniformly sprayed on the spraying part of the low-temperature connector can be any one of a wet method and a dry method, wherein,

the wet method is to spray the Teflon dispersion liquid raw material on the surface of the part of the low-temperature connector needing to be sprayed by a spray gun;

in the dry method, powdery Teflon raw material is blown out of the trap by high-pressure gas to form uniform cloud-shaped spray, so that the spray is attached to the surface of the part of the low-temperature connector to be sprayed.

In the same embodiment, the thickness of the coating sprayed on the spraying part of the low-temperature connector is B, and B is more than or equal to 5 mu m and less than or equal to 200 mu m.

In the same embodiment, the wet process further comprises: and heating the low-temperature connector sprayed with the wet Teflon coating in a baking furnace, wherein the heating temperature is C, C is more than or equal to 60 ℃ and less than or equal to 100 ℃, the heating time is T, and T is more than or equal to 2h and less than or equal to 4 h.

In the same embodiment, the high-temperature heating temperature for bonding the Teflon raw material and the low-temperature connector in a molten state is D, wherein D is more than or equal to 360 ℃ and less than or equal to 400 ℃.

In a further aspect of the invention, a cryogenic connector is provided, which includes an arrow-top interface structure and a ground interface structure, where the ground interface structure includes a first connecting body and a locking structure provided on the first connecting body, two ends of the locking structure are respectively connected to the arrow-top interface structure and the first connecting body, the arrow-top interface structure is used for being connected to a pipeline on an arrow, the first connecting body is used for being connected to a ground pipeline to ensure that a cryogenic propellant medium on the ground is conveyed onto the arrow, where,

the locking structure comprises a clamping jaw, a pin shaft and a pressing ring, the pressing ring is sleeved at one end of the first connecting body close to the arrow upper interface structure, the pin shaft penetrates through the pressing ring and the clamping jaw, the clamping jaw is configured to freely rotate along the surface of the pin shaft so as to control the arrow upper interface structure to be locked/separated with/from the first connecting body,

the surfaces of the joint ends of the arrow upper interface structure and the first connecting body, and the clamping jaws and the pressure rings are respectively provided with a Teflon coating, and the Teflon coatings are tightly attached to the surfaces of the arrow upper interface structure, the ground interface structure, the clamping jaws and the pressure rings;

the Teflon coating is used for reducing icing at the joint of the rocket interface structure and the first connecting body, so that after the coolant in the rocket is filled, the rocket interface structure is safely separated from the ground interface structure.

Compared with the prior art, the embodiment of the invention has at least one of the following advantages:

firstly, the Teflon raw material is uniformly sprayed on the surface of the low-temperature connector, so that the icing on the surface of the low-temperature connector can be reduced, and when the low-temperature propellant is filled, the connector and a rocket pipeline can fall off conveniently, thereby being beneficial to the launching of the rocket.

The second, through heating low temperature connector high temperature for teflon raw materials and low temperature connector bonding under the molten condition, and then make the teflon raw materials be connected inseparabler with low temperature connector, and it is fixed more firm. The Teflon coating can be prevented from falling off from the surface of the low-temperature connector, and the reliability of the connector is improved.

Third, the connector that this application embodiment provided has optimized spare part structure, has improved production efficiency. According to the invention, the Teflon coatings are respectively arranged on the surface of the butt joint end connected with the arrow upper interface structure and the ground interface structure, and the clamping jaws and the pressure rings, and have the advantages of non-adhesiveness (low viscosity) and good low-temperature stability, so that the icing phenomenon can be reduced, the influence on the use effect caused by the deformation of the Teflon coatings can be avoided due to the low-temperature stability of the Teflon coatings, the whole design is improved slightly, and parts do not need to be redesigned.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawings

FIG. 1 is a schematic diagram of a ground interface structure of the present invention;

FIG. 2 is a schematic structural diagram of an arrow-top interface structure according to the present invention;

FIG. 3 is a schematic diagram of the cryogenic connector assembly of the present invention;

FIG. 4 is a cross-sectional view of the cryogenic connector assembly of the present invention;

FIG. 5 is a schematic view of the epitaxial portion of the present invention;

FIG. 6 is a schematic view of the pin shaft structure of the present invention;

FIG. 7 is a process flow diagram of the present invention;

FIG. 8 is a schematic diagram showing the adhesion between the Teflon material and the low temperature connector of the present invention as the temperature changes.

Description of reference numerals:

1 arrow upper interface structure 2 jack catch

3 round pin axle 4 clamping rings

5 ground interface Structure 6 coating

7 coating structure 8 epitaxial body

9 extension part

Detailed Description

For the purpose of promoting a clear understanding of the objects, aspects and advantages of the embodiments of the invention, reference will now be made to the drawings and detailed description, wherein there are shown in the drawings and described in detail, various modifications of the embodiments described herein, and other embodiments of the invention will be apparent to those skilled in the art.

The exemplary embodiments of the present invention and the description thereof are provided to explain the present invention and not to limit the present invention. Additionally, the same or similar numbered elements/components used in the drawings and the embodiments are used to represent the same or similar parts.

As used herein, the terms "first," "second," …, etc., do not denote any order or sequence, nor are they used to limit the present invention, but rather are used to distinguish one element from another or from another element or operation described in the same technical language.

With respect to directional terminology used herein, for example: up, down, left, right, front or rear, etc., are simply directions with reference to the drawings. Accordingly, the directional terminology used is intended to be illustrative and is not intended to be limiting of the present teachings.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

As used herein, "and/or" includes any and all combinations of the described items.

As used herein, the terms "substantially", "about" and the like are used to modify any slight variation in quantity or error that does not alter the nature of the variation. Generally, the range of slight variations or errors modified by such terms may be 20% in some embodiments, 10% in some embodiments, 5% in some embodiments, or other values. It should be understood by those skilled in the art that the aforementioned values can be adjusted according to actual needs, and are not limited thereto.

Certain words used to describe the present application are discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the present application.

Referring to fig. 7, the invention provides a surface coating process for a low-temperature connector of a liquid rocket, which mainly comprises the following steps:

s1: providing a low-temperature connector, and cleaning the surface of the low-temperature connector;

s2: uniformly spraying a Teflon raw material on the surface of the low-temperature connector;

s3: and heating the low-temperature connector at a high temperature to bond the Teflon raw material in a molten state with the low-temperature connector.

In order to facilitate spraying of the teflon raw material, influence of impurities on characteristics of the teflon raw material is reduced, for example, when the surface of the low-temperature connector is subjected to cleaning treatment, the surface of the low-temperature connector can be subjected to cleaning treatment by an organic solvent. The organic solvent may be ethanol, acetone, diethyl ether, styrene, etc., which are not illustrated herein.

In this embodiment, in order to facilitate the volatilization of the organic solvent, for example, the cleaning process of the surface of the low-temperature connector by the organic solvent includes: and heating the low-temperature connector to volatilize the organic solvent on the surface of the low-temperature connector. The temperature for heating the low-temperature connector can be 270 ℃, 300 ℃, 330 ℃ and the like, and a large amount of experimental data show that the temperature for heating the low-temperature connector to volatilize the organic solvent on the surface is A, and when the temperature is more than or equal to 300 ℃ and less than or equal to 400 ℃, the organic solvent is ensured to be quickly volatilized from the surface of the low-temperature connector.

For example, before the teflon raw material is uniformly sprayed on the surface of the spraying part of the low-temperature connector, the method further includes: the surface-sprayed portion of the low-temperature connector is subjected to sand blasting to roughen the surface thereof. The specific steps of carrying out sand blasting treatment on the surface spraying part of the low-temperature connector to roughen the surface of the low-temperature connector are as follows: preparing 40-70 mesh quartz sand and 170-180 mesh brown corundum according to the proportion of 2:1, spraying the quartz sand and the brown corundum to the spraying part of the low-temperature connector by using high-pressure gas to assist in spraying the quartz sand and the brown corundum to the spraying part of the low-temperature connector, enabling the surface roughness (Ra) of the low-temperature connector to reach 2.0-3.5 mu m, and cleaning the surface of the low-temperature connector.

In particular, in order to facilitate uniform spraying of the teflon raw material, for example, the surface of the low-temperature connector to be uniformly sprayed with the teflon raw material may be either wet or dry.

The wet method is to spray the teflon dispersion liquid raw material on the surface of the low-temperature connector to be sprayed by a spray gun. Specifically, the wet method adopted in this embodiment is to spray a teflon dispersion raw material onto the surface of the low-temperature connector by using a spray gun with a diameter of 1.0-1.5 mm under a pressure of 0.2-0.3 MPa. The distance between the spray gun and the surface of the low-temperature connector is 20-30 cm, the spray gun and the surface of the low-temperature connector part run in parallel at 90 degrees, and the moving speed of the spray gun is 30-60 cm/s. By adjusting the parameters of wet spraying, a low-temperature connector coating product with more compact and stable connection is obtained. In addition, in order to evaporate the liquid medium of the raw material of the teflon dispersion, for example, when the wet process is followed, the method further includes: and heating the low-temperature connector sprayed with the wet Teflon coating in a baking furnace, wherein the heating temperature is C, C is more than or equal to 60 ℃ and less than or equal to 100 ℃, the heating time is T, and T is more than or equal to 2h and less than or equal to 4 h.

The dry method is described, in which powdered teflon raw material is blown out from a trap by high-pressure gas to form uniform cloud-shaped spray, so that the spray is attached to the surface of the part of the low-temperature connector to be sprayed. In the whole process of dry spraying, the spray gun is connected with a negative electrode, a part to be sprayed is connected with a positive electrode (grounded), and an electrostatic region is formed between the spray gun and the part. Repeated tests show that the voltage of the electrostatic spray gun is adjusted to be 25-40 kV, and the spray gun with the caliber of 1.0-1.5 mm is used for blowing the powdery Teflon raw material out of the catcher by compressed air under the pressure of 0.08-0.12 MPa, so that the powdery Teflon raw material with better dispersion state can be obtained. On the way of the powdery Teflon raw material to the spray gun nozzle, the powdery Teflon raw material passes through an electrostatic area and is charged with negative charges, and because the particles are charged with the same kind of charges, the particles repel each other on the flight path of the particles to form uniform cloud-shaped spray. The Teflon powder particles are attracted by the positive charges of the parts and are attached to the parts of the low-temperature connector to be sprayed. Different from wet spraying, the parameters of the spray gun need to be adjusted, through tests, the distance between the spray gun and the surface of a part is 12-18 cm, the spray gun and the surface of the part of the low-temperature connector run in parallel at 90 degrees, and the moving speed of the spray gun is 10cm/s, the dispersion state of powder-loaded Teflon is the best, the charge carrying is more uniform, and meanwhile, the surface of the low-temperature connector is more compact.

A large number of experiments prove that when the thickness of the coating sprayed on the spraying part of the low-temperature connector is B and the requirement that B is more than or equal to 5 mu m and less than or equal to 200 mu m is met, the icing on the surface of the low-temperature connector can be reduced, and the sealing performance of the low-temperature connector is more rigorous.

As shown in figure 8, the high temperature heating temperature for bonding the Teflon raw material and the low temperature connector in the molten state is D, wherein when the requirement that D is more than or equal to 360 ℃ and less than or equal to 400 ℃, the Teflon raw material and the low temperature connector are more tightly connected and more firmly fixed (the X axis represents the temperature, the Y axis represents the bonding degree, namely the firm degree for bonding the Teflon raw material and the low temperature connector), and the low temperature connector has low deformation probability.

With the long-term use of the low-temperature connector, the teflon raw material on the surface of the low-temperature connector becomes thin or even falls off due to abrasion, and the teflon raw material at the thinned part needs to be removed and coated again. When the area of the thinned part is smaller than 4 square centimeters, the thinned part is cleaned by a cutting knife to expose the surface of the low-temperature connector, then the Teflon dispersion liquid raw material can be sprayed on the surface of the part of the low-temperature connector to be sprayed (the thinned part is cleaned) by a wet method, and the Teflon raw material is bonded with the low-temperature connector after subsequent heating. And when the area of the thinned part is larger than 4 square centimeters, heating and melting the Teflon raw material at the thinned part by using a high-temperature spray gun, spraying powdery Teflon raw material on the surface of the part, needing to be sprayed, of the low-temperature connector by using a dry method, and heating to bond the Teflon raw material with the low-temperature connector.

After the Teflon raw material in a molten state is bonded with the low-temperature connector, the low-temperature connector is placed in a cold environment (the temperature is between-220 ℃ and-196 ℃), and the product quality is judged by observing the elongation of the Teflon raw material on the surface of the low-temperature connector. When the elongation of the Teflon raw material (the diameter of the raw material molecules) is less than 5%, the low-temperature connector coating (the Teflon raw material is adhered to the part, required to be sprayed, of the low-temperature connector) is qualified.

In a further aspect of the invention, as shown in fig. 1, fig. 2, fig. 3, fig. 4, fig. 5 and fig. 6, the cryogenic connector assembly comprises an arrow interface structure 1 and a ground interface structure 5, the ground interface structure 5 comprises a first connecting body and a locking structure arranged on the first connecting body, two ends of the locking structure are respectively connected with the arrow interface structure 1 and the first connecting body, the arrow interface structure 1 is used for being connected with a pipeline on the arrow, and the first connecting body is used for being connected with the ground pipeline to ensure that a cryogenic propellant medium on the ground is conveyed onto the arrow. The locking structure comprises a clamping jaw 2, a pin shaft 3 and a pressing ring 4, the pressing ring 4 is sleeved at one end, close to the arrow-mounted interface structure 1, of the first connecting body, the pin shaft 3 penetrates through the pressing ring 4 and the clamping jaw 2, and the clamping jaw 2 is configured to freely rotate along the surface of the pin shaft 3 so as to be used for controlling locking/separation of the arrow-mounted interface structure 1 and the first connecting body. The surfaces of the joint end of the arrow upper interface structure 1 and the first connecting body, the clamping jaw 2 and the pressing ring 4 are respectively provided with a Teflon coating, and the Teflon coatings are tightly attached to the surfaces of the arrow upper interface structure 1, the first connecting body, the clamping jaw 2 and the pressing ring 4.

The Teflon coating is used for reducing the icing phenomenon at the joint of the rocket interface structure 1 and the first connecting body, and after the coolant in the rocket is filled, the rocket interface structure is safely separated from the ground interface structure.

Besides the spraying part, the surface protection measures, especially the sealing part, are taken to the surface of the low-temperature connector part. A special shield or textured paper may be used to shield the non-sprayed areas.

Referring to fig. 1 and 3, an embodiment of the present invention provides a ground interface structure of a cryogenic connector, including a first connecting body and a locking structure disposed on the first connecting body, where the first connecting body has two ends that are communicated with each other and an internal channel for flowing cryogenic propellant, and the locking structure is disposed on a circumferential outer surface of the first connecting body and is used to connect the first connecting body with an arrow connector connected to the arrow connector, so as to transport the cryogenic propellant on the ground to the arrow.

One end of the first connecting body, which is used for connecting the arrow upper connecting body, is provided with a coating 7 for reducing the icing on the surface of the first connecting body.

In order to reduce the formation of ice on the surface of the first connecting body, the coating 7 is a teflon coating, for example, and in order to ensure that the teflon coating is tightly connected with the first connecting body, the teflon coating is firmly fixed, for example, the teflon coating is thermally molded on the surface of the first connecting body.

In addition, the locking structure comprises a clamping jaw 2, a pin shaft 3 and a pressing ring 4, the pressing ring 4 is sleeved on the outer side of the first connecting body and is connected with the first connecting body, the clamping jaw 2 is fixed on the pressing ring 4 through the pin shaft 3, and the clamping jaw 2 freely rotates along the circumferential surface of the pin shaft 3 and is used for controlling the first connecting body and the arrow to be locked and separated.

It is pointed out that the use of the jaws 2 (fixed against rotation after freezing) is impaired in order to avoid moisture freezing on the jaws 2, for example, the surfaces of the jaws 2 are provided with teflon coatings.

Another aspect of the present invention provides an arrow-top interface structure of a cryogenic connector, as shown in fig. 2, fig. 3, fig. 4 and fig. 5, the arrow-top interface structure includes a second connecting body and an extension body 8, the extension body 8 is convexly disposed on a circumferential outer surface of the second connecting body and is close to one side of a ground interface structure of the cryogenic connector, the second connecting body has two ends that are communicated with each other and is internally provided with a channel for circulating a cryogenic propellant, and a coating structure 6 for reducing icing on the surface of the second connecting body is disposed at one end of the second connecting body and one end of the extension body 8 close to the ground interface structure.

It should be noted that, in order to facilitate the fixing of the second connector and the arrow upper pipeline, for example, one end of the second connector far away from the outer body 8 (i.e. the end opposite to the outer body 8) is further provided with an outer extension portion 9, the outer extension portion 9 is convexly arranged along the circumferential surface of the second connector and is fixedly connected with the second connector, the outer extension portion 9 is used for being connected with the arrow upper pipeline, the design of the outer extension portion 9 can increase the contact area with the arrow upper pipeline, and the connection between the two is facilitated.

It is particularly noted that to facilitate the delivery of the cryogenic propellant, the second connector is, for example, a cylindrical structure with two ends in communication. In addition, in order to facilitate the engagement with the jaws, the jaws are opened conveniently, for example, upper and lower side lines formed by intersecting the extension body 8 along the axial direction of the extension body 8 are extended and connected to form an isosceles trapezoid. Wherein, isosceles trapezoid's long limit is close to one side of ground interface structure 5, and the one side of ground interface structure 5 is kept away from to the minor face, and when opening of jack catch, only need do less rotation (for example, rotate less radian) along the round pin axle, and then make things convenient for interface structure 1 separation on ground interface structure and the arrow.

In addition, in practical applications, in order to connect the extension body 8 and the second connection body tightly, the extension body 8 and the second connection body are fixed firmly, for example, integrally formed. Furthermore, the coating structure 6 is a teflon coating provided by means of thermoplasticity. It should be further noted that, in order to make coating structure 6 and second connector surface connection inseparabler, it is fixed more firm, for example, epitaxial body 8 and second connector surface are equipped with the ripple structure of the fixed coating structure 6 of cooperation, the design of ripple structure can increase epitaxial body 8 and second connector surface and coating structure 6's area of contact, when adopting the thermoplastic mode to connect, can effectively prevent coating structure 6 and drop, and then reduce to freeze (a small amount of icing does not influence the separation of connector), make things convenient for the connector to drop, and then be favorable to the launch of rocket.

In the present invention, the application of the teflon coating in the low temperature connector has the following properties: 1. non-stick property: the coated surface has extremely low surface tension and thus exhibits extremely strong non-tackiness. 2. Sliding property: teflon coatings have a low coefficient of friction, which varies during load sliding, but only between 0.05 and 0.15. 3. Low-temperature stability: teflon coatings can tolerate severe absolute zero without loss of mechanical properties and can be used at temperatures as low as-240 ℃. 4. Corrosion resistance: the teflon coating can withstand the action of all strong acids (including aqua regia), strong oxidants, reducing agents and various organic solvents except molten alkali metals, fluorinated media and sodium hydroxide above 300 ℃, and can protect parts from any kind of chemical corrosion. And teflon includes PTFE, FEP, PFA, ETFE, etc. types.

Compared with the prior art, the invention has at least one of the following advantages:

firstly, the Teflon raw material is uniformly sprayed on the surface of the low-temperature connector, so that the icing on the surface of the low-temperature connector can be reduced, and when the low-temperature propellant is filled, the connector and a rocket pipeline can fall off conveniently, thereby being beneficial to the launching of the rocket.

The second, through heating low temperature connector high temperature for teflon raw materials and low temperature connector bonding under the molten condition, and then make the teflon raw materials be connected inseparabler with low temperature connector, and it is fixed more firm. The Teflon coating can be prevented from falling off from the surface of the low-temperature connector, and the reliability of the connector is improved.

Third, the connector that this application embodiment provided has optimized spare part structure, has improved production efficiency. According to the invention, the Teflon coatings are respectively arranged on the surface of the butt joint end connected with the arrow upper interface structure and the ground interface structure, and the clamping jaws and the pressure rings, and have the advantages of non-adhesiveness (low viscosity) and good low-temperature stability, so that the icing phenomenon can be reduced, the influence on the use effect caused by the deformation of the Teflon coatings can be avoided due to the low-temperature stability of the Teflon coatings, the whole design is improved slightly, and parts do not need to be redesigned.

The whole process has the advantages of reasonable design, stable structure, reduction of the freezing phenomenon, convenience for the falling of the connector after the low-temperature propellant is filled, and the like.

The foregoing is merely an illustrative embodiment of the present invention, and any equivalent changes and modifications made by those skilled in the art without departing from the spirit and principle of the present invention should fall within the protection scope of the present invention.