Flywheel nut unlock and release mechanism for launch vehicle fairing separation

Abstract

The present application relates to a flywheel nut unlocking and separating mechanism for separating the fairing of a carrier rocket, comprising a shell, a flywheel nut, a first screw rod, a second screw rod and a locking assembly are arranged in the shell, the screw threads of the first screw rod and the second screw rod are opposite in rotation direction, and the first screw rod and the second screw rod are screwed on the flywheel nut from the axial two ends of the flywheel nut respectively, forming a non-self-locking screw thread structure, the outer ends of the first screw rod and the second screw rod are extended out of the shell and are used for connecting the fairing and the rocket body or the payload respectively, the locking assembly is used for locking the flywheel nut to prevent axial rotation, when the locking of the flywheel nut by the locking assembly is released, the flywheel nut rotates under the pre-tightening force of the first screw rod and the second screw rod, the first screw rod and the second screw rod move linearly along the axial direction to two sides respectively until they are separated from the flywheel nut, and the separation of the fairing from the carrier rocket is realized. The present application adopts a non-explosive separation mode, has the characteristics of small impact force, high reliability, large carrying capacity and high compactness.

Description

Technical Field

[0001] This invention relates to a flywheel nut unlocking and separation mechanism for separating launch vehicle fairings, and belongs to the field of launch vehicle fairing separation technology. Background Technology

[0002] Fairing separation of a launch vehicle is a critical step in ensuring normal flight and mission success. The fairing is part of the overall structure of the rocket during the launch phase and is used to protect the internal payload from air resistance and temperature changes. It needs to separate when the rocket enters a higher flight level to reduce weight and improve flight efficiency.

[0003] Under current technology, the separation of the fairing from the launch vehicle mainly employs pyrotechnic separation techniques, such as explosive bolts and pyrotechnic nuts. While pyrotechnic separation provides high energy density and rapid response, it results in significant separation impact, which can easily affect the launch vehicle's attitude control and payload stability, increasing system uncertainty. Furthermore, it is a single-use technique, leading to high testing costs and material waste. As space missions demand increasing precision and safety, traditional pyrotechnic separation mechanisms are gradually becoming insufficient to meet the practical requirements of fairing separation from launch vehicles. Summary of the Invention

[0004] To overcome the above-mentioned defects of the prior art, the present invention provides a flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle. It adopts a non-pyrotechnic separation method and has the characteristics of high reliability, large load-bearing capacity, high compactness and reusability.

[0005] The technical solution adopted in this invention is: a flywheel nut unlocking and separation mechanism for separating a launch vehicle fairing, comprising a housing, a flywheel nut, a first screw, a second screw, and a locking assembly inside the housing. The first screw and the second screw have opposite thread directions and are screwed onto the flywheel nut from their respective axial ends, forming a non-self-locking thread structure. The outer ends of the first screw and the second screw both extend out of the housing and are used to connect the fairing to the rocket body or payload, respectively. The locking assembly is used to lock the flywheel nut to prevent its axial rotation. When the locking assembly releases the lock on the flywheel nut, under the preload of the first screw and the second screw, the flywheel nut rotates, and the first screw and the second screw move linearly to both sides along the axial direction until they disengage from the flywheel nut, thus realizing the separation of the fairing from the launch vehicle.

[0006] Preferably, the thread helix angle (or lead angle) of both the first screw and the second screw is 10°~12°.

[0007] Furthermore, the thread helix angle of both the first screw and the second screw is 10.78°.

[0008] Preferably, the thread friction angle of both the first screw and the second screw is 6°~9°.

[0009] Furthermore, the thread friction angle of both the first screw and the second screw is 8.8°.

[0010] Preferably, the flywheel nut has an outwardly extending locking portion on its outer wall, and the locking assembly locks the flywheel nut by limiting and constraining the locking portion.

[0011] Preferably, the locking portion extends outward along the tangential direction of the flywheel nut's circumference.

[0012] Preferably, the locking part is rod-shaped or rectangular block-shaped.

[0013] Preferably, the locking assembly includes several stages of rotating shafts, each stage of which is arranged in parallel and rotatably connected to the housing. At least the other stages of rotating shafts, except for the first stage, are provided with torsion springs between themselves and the housing. Each stage of rotating shafts is provided with a connecting rod extending radially outward, and each stage of rotating shafts is provided with a limiting groove extending radially inward. The outer end of the connecting rod on the other stages of rotating shafts, except for the first stage, is engaged in the limiting groove on the next stage rotating shaft. The outer end of the locking part is engaged in the limiting groove on the last stage rotating shaft, thereby locking the flywheel nut with the locking assembly. The outer end of the connecting rod on the first stage rotating shaft serves as the unlocking operation end of the locking assembly.

[0014] Preferably, the axis of each of the rotating shafts is parallel to the axis of the flywheel nut.

[0015] Preferably, the limiting grooves on each of the rotating shafts are through grooves in the axial direction perpendicular to the corresponding rotating shaft, and the depth of the limiting grooves on each of the rotating shafts is not less than the length of the outer end portion of the corresponding locking part or the outer end portion of the connecting rod that is stuck therein.

[0016] Preferably, a cylinder is fixedly installed on the outer wall of the housing, and the piston rod of the cylinder extends into the housing. The outer end of the piston rod abuts against or is rotatably connected to the outer end of the connecting rod on the first-stage rotating shaft, which is used to limit and constrain the outer end of the connecting rod on the first-stage rotating shaft and to unlock the locking assembly.

[0017] Preferably, the axis of the piston rod is perpendicular to the axis of the first-stage rotating shaft.

[0018] Preferably, the number of the rotating shafts is three, that is, the locking assembly includes three-stage rotating shafts.

[0019] Preferably, the number of connecting rods on each stage of the rotating shaft is one or two. When the number of connecting rods on the rotating shaft is two, the two connecting rods are arranged in parallel and extend outward from the rotating shaft in the same direction.

[0020] Preferably, the housing is provided with through-holes that allow the connecting rods on each stage of the rotating shaft to pass through during rotation.

[0021] The beneficial effects of this invention are:

[0022] (1) The unlocking and separation mechanism of the present invention adopts a non-pyrotechnic separation method. Compared with the traditional pyrotechnic separation technology, the impact force is small when the fairing separates from the launch vehicle. It will not affect the attitude control of the launch vehicle and the stability of the payload. It can also eliminate the risk of high-temperature gas and debris pollution and avoid strong electromagnetic pulse interference. It has the characteristics of high reliability, large load-bearing capacity and high compactness. At the same time, the unlocking and separation mechanism of the present invention can be repeatedly operated and reused, and supports multiple locking and separation, which can significantly reduce mission costs and material waste. (2) The unlocking and separation mechanism of the present invention uses the flywheel nut to convert the elastic potential energy of the load connection unlocking into rotational kinetic energy. By controlling the rotation of the flywheel nut, the locking and separation of the separation mechanism can be realized, which can effectively improve the stability of the separation between the fairing and the launch vehicle. (3) The unlocking and separation mechanism of the present invention combines a force-increasing mechanism based on a coaxial lever mechanism and a large-height non-self-locking thread structure to effectively amplify the input force (or driving force, constraint force) of the separation mechanism, amplify the input force to achieve locking and unlocking of large loads, and make the separation mechanism have extremely strong load-bearing capacity.

[0023] (4) The unlocking and separation mechanism of the present invention also has the characteristics of compact structure, small size and small space occupation. Attached Figure Description

[0024] Figure 1 This is a structural schematic diagram of one embodiment of the present invention (a cross-sectional view of the shell in the figure). Figure 2 yes Figure 1 A schematic diagram of the connection and separation component in the implementation embodiment; Figure 3 yes Figure 1 A schematic diagram of the locking state of the locking component in the embodiment; Figure 4 yes Figure 1 A schematic diagram of the unlocked state of the locking component in the implementation embodiment.

[0025] In the diagram, 1-housing; 2-connection and separation assembly; 21-flywheel nut; 22-first screw; 23-second screw; 24-locking part; 3-locking assembly; 31-first shaft; 32-second shaft; 33-third shaft; 34-first connecting rod; 35-second connecting rod; 36-third connecting rod; 4-cylinder. Detailed Implementation

[0026] See Figures 1-4 This invention discloses a flywheel nut unlocking and separation mechanism for separating a launch vehicle fairing, comprising a housing 1, wherein a connecting and separating component 2 and a locking component 3 are provided inside the housing. The housing is used to provide external protection and internal support for the connecting and separating component and the locking component, ensuring that the connecting and separating component and the locking component are stably fixed inside and can withstand the force generated when the unlocking and separation mechanism moves. The connection and separation assembly is used to connect and separate the fairing from the rocket body / payload. The connection and separation assembly includes a flywheel nut 21, a first screw 22, and a second screw 23. The first screw and the second screw have opposite thread directions. The internal thread of the flywheel nut mates with the external threads of the first screw and the second screw. The first screw and the second screw are screwed onto the flywheel nut from both axial ends, forming a large lift angle non-self-locking thread structure. The flywheel nut has one rotational degree of freedom, enabling fixed-axis rotation. The first screw and the second screw each have one linear motion degree of freedom, enabling axial linear motion. Limiting any one of the flywheel nut, the first screw, and the second screw can effectively lock the bidirectional thread. After the limit is released, the flywheel nut rotates, and the first screw and the second screw both retract axially in a linear fashion until they disengage from the flywheel nut, achieving simultaneous unlocking on both sides. The outer ends of the first and second screws both extend from the housing. The housing has through holes for the first and second screws to pass through. The outer ends of the first and second screws are respectively used to connect the fairing and the rocket body / payload. The locking assembly is used to lock the flywheel nut. Through the large-lift angle non-self-locking thread structure between the flywheel nut and the first and second screws, the axial load on the first and second screws is converted into the torque of the flywheel nut, constraining the rotational freedom of the flywheel nut and preventing its axial rotation, thus achieving the locking mechanism (locking between the fairing and the rocket body / payload). When the locking assembly releases the locking of the flywheel nut, under the preload of the first and second screws, the flywheel nut rotates axially, and the first and second screws move linearly to both sides along the axial direction until they disengage from the flywheel nut, realizing the separation of the fairing from the launch vehicle.

[0027] The lead angle (or helix angle) of both the first and second screws is 10°~12°, for example, 10°, 11°, or 12°, preferably 10.78°. The friction angle of both the first and second screws is 6°~9°, for example, 6°, 8°, or 9°, preferably 8.8°. This allows the first screw, the second screw, and the flywheel nut to form a high-efficiency, large-helix-angle, non-self-locking thread structure.

[0028] The flywheel nut preferably has an outwardly extending locking portion 24 on its outer wall. The locking assembly locks the flywheel nut by limiting and constraining the locking portion. The locking portion preferably extends outward along the tangent direction of the flywheel nut's circumference. The locking portion can be rod-shaped or rectangular block-shaped to facilitate the locking assembly in locking and unlocking the flywheel nut.

[0029] The locking assembly preferably includes several stages of rotating shafts, each stage of which is arranged in parallel and rotatably connected to the housing. At least one stage of rotating shaft (except the first stage) has a torsion spring between itself and the housing (or all stages of rotating shafts may have a torsion spring between themselves and the housing). This spring provides power for the rotation of each stage of rotating shafts after the locking assembly releases the flywheel nut, assisting in unlocking. Each stage of rotating shaft has a radially outwardly extending connecting rod, and each stage of rotating shaft has a radially inwardly opening limiting groove on its outer wall. The limiting groove can also be located at the end of the connecting rod connecting to its respective rotating shaft. The outer end of the connecting rod on each stage of rotating shaft (except the first stage) is engaged in the limiting groove on the previous stage of rotating shaft, and the outer end of the locking part is engaged in the limiting groove on the last stage of rotating shaft, thus locking the flywheel nut with the locking assembly. The outer end of the connecting rod on the first stage of rotating shaft serves as the unlocking operation end of the locking assembly. Each of the rotating shafts provides the foundation for support and rotation. The limiting grooves on each of the rotating shafts constrain the movement of the connecting rods and the flywheel nut. The connecting rods on each of the rotating shafts form a motion chain, and each connecting rod is used to transmit power from one part (the part consisting of the rotating shaft and its connecting rods) to another part, achieving force transmission through rotation and surface contact. Each of the rotating shafts and its connecting rods forms a coaxial lever mechanism, which can be considered a variation of a lever mechanism. Its force transmission is essentially a lever effect. The rotating shaft is equivalent to the fulcrum of a common lever mechanism. By designing the lengths of the main arm and the driven arm, different force amplification coefficient ratios can be achieved, enabling the unlocking and separation mechanism to achieve high-load locking with a relatively small driving force (or constraint force).

[0030] The limiting grooves on each stage of the rotating shaft are preferably through grooves along the axial direction perpendicular to the corresponding rotating shaft. The depth of the limiting grooves on each stage of the rotating shaft is preferably not less than the length of the outer end of the corresponding locking part or the outer end of the connecting rod that is stuck therein. This is so that when the outer end of the connecting rod on the first-stage rotating shaft is unlocked, and each stage of the rotating shaft rotates under the action of the torsion spring (when there is no torsion spring between the first-stage rotating shaft and the housing, when the outer end of the connecting rod on the first-stage rotating shaft is unlocked, the other stage rotating shafts except the first-stage rotating shaft will have a rotational tendency or rotation under the action of the torsion spring, and the first-stage rotating shaft will also rotate under the rotational tendency or rotation of the other stage rotating shafts), the outer end of the locking part or the outer end of the connecting rod can smoothly disengage from the limiting groove on the corresponding rotating shaft, thereby unlocking the flywheel nut.

[0031] A preferred embodiment of the locking assembly is as follows: the locking assembly includes a first rotating shaft 31, a second rotating shaft 32, and a third rotating shaft 33. Each rotating shaft is arranged in parallel and rotatably connected to the housing. A torsion spring is provided between the second rotating shaft and the third rotating shaft and the housing. Typically, a first connecting rod is located between the second connecting rod and the third connecting rod. A first connecting rod 34 extends radially outward from the first rotating shaft, a second connecting rod 35 extends radially outward from the second rotating shaft, and a third connecting rod 36 extends radially outward from the third rotating shaft. A first limiting groove is provided on the first rotating shaft, a second limiting groove is provided on the second rotating shaft, and a third limiting groove is provided on the third rotating shaft. The first limiting groove, the second limiting groove, and the third connecting rod 33... All three limiting grooves are through grooves along an axial direction perpendicular to their respective rotating shafts. The outer end of the locking part is engaged in the third limiting groove, the outer end of the third connecting rod is engaged in the second limiting groove, and the outer end of the second connecting rod is engaged in the first limiting groove, thereby locking the flywheel nut with the locking assembly. The depth of the first limiting groove is not less than the length of the outer end portion of the second connecting rod engaged therein, the depth of the second limiting groove is not less than the length of the outer end portion of the third connecting rod engaged therein, and the depth of the third limiting groove is not less than the length of the outer end portion of the locking part engaged therein. The outer ends of the second connecting rod, the third connecting rod, and the locking part may be provided with notches suitable for engaging into the corresponding limiting grooves. The outer end of the first connecting rod serves as the unlocking operation end of the locking assembly. Preferably, the axes of the first rotating shaft, the second rotating shaft, and the third rotating shaft are all parallel to the axis of the flywheel nut.

[0032] A cylinder 4 is preferably fixedly installed on the outer wall of the housing. The piston rod of the cylinder extends into the housing, and the housing has a through hole through which the piston rod can pass. The outer end of the piston rod abuts against or is rotatably connected to the outer end of the first connecting rod, for limiting the outer end of the first connecting rod and unlocking the locking assembly. The axis of the piston rod is preferably perpendicular to the axis of the first rotating shaft. The cylinder serves as the driving part of the unlocking and separating mechanism, and realizes the locking and unlocking operations of the unlocking and separating mechanism through pneumatic drive. The cylinder controls the locking assembly to move accordingly by applying or releasing pressure, thereby controlling the unlocking and separating mechanism to be in a locked or unlocked state. When the unlocking and separating mechanism is in the locked state, the cylinder applies a driving force to the outer end of the first connecting rod. Through the transmission of force between each rotating shaft and the connecting rod and the mutual limiting action between them, the locking assembly is locked. The locking part is locked by the third rotating shaft and the third limiting groove thereon. When the unlocking and separation mechanism is unlocked, the cylinder reduces the driving force, and each connecting rod and rotating shaft rotates relative to each other under the action of the torsion spring, releasing the locking state between them. The limit on the flywheel nut (referring to the locking part on the flywheel nut) is released, and the flywheel nut rotates freely, thereby unlocking the unlocking and separation mechanism and separating the fairing from the rocket body / payload.

[0033] The number of the first link, the second link, and the third link is one or two. Typically, there is one first link, located at the axial center of the first rotating shaft; there are two second links, arranged parallel to each other and extending radially outward from the second rotating shaft in the same direction, symmetrically positioned on the second rotating shaft with its axial center as the center; and there are two third links, arranged parallel to each other and extending radially outward from the third rotating shaft in the same direction, symmetrically positioned on the third rotating shaft with its axial center as the center.

[0034] Preferably, the housing has an inner and outer through-hole for the first, second, and third connecting rods to pass through when they rotate, so as to avoid the housing interfering with the rotation of each connecting rod.

[0035] The unlocking and separation mechanism includes two working processes: locking and separating.

[0036] Locking process: During the locking process, the first bolt and the second bolt are screwed into the flywheel nut from both ends. After the first screw and the second screw are screwed into the flywheel nut to the designated position, the first shaft, the second shaft and the third shaft are rotated respectively, so that the first connecting rod, the second connecting rod and the third connecting rod reach the locking position respectively. The cylinder provides thrust to the first connecting rod (the piston rod pushes against the first connecting rod), and the third limiting groove on the third shaft is used to constrain the flywheel nut, thus completing the locking.

[0037] Separation process: When the launch vehicle issues the fairing separation signal, the piston rod of the cylinder retracts, reducing the driving force on the locking assembly (referring to the first connecting rod), causing the locking force of the locking assembly to disappear. Each connecting rod and each rotating shaft begins to rotate under the action of the torsion spring. The constraint of the third limiting groove on the third rotating shaft on the flywheel nut disappears. Under the torque generated when the non-self-locking thread of the flywheel nut is under load, the flywheel nut rotates clockwise. The first screw and the second screw both retract axially in a straight line until they disengage from the flywheel nut, completing the separation.

[0038] Unless otherwise specified or further limited to one preferred or optional technical means being another, the preferred and optional technical means disclosed in this invention can be arbitrarily combined to form several different technical solutions.

Claims

1. A flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle, characterized in that... The system includes a housing, within which are a flywheel nut, a first screw, a second screw, and a locking assembly. The first and second screws have opposite thread directions and are screwed onto the flywheel nut from both axial ends, forming a non-self-locking thread structure. The outer ends of the first and second screws extend from the housing and are used to connect the fairing to the rocket body or payload, respectively. The locking assembly locks the flywheel nut to prevent axial rotation. When the locking assembly releases the flywheel nut, the flywheel nut rotates under the preload of the first and second screws, and the first and second screws move linearly to both sides axially until they disengage from the flywheel nut, thus separating the fairing from the launch vehicle.

2. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to claim 1, characterized in that... The thread helix angle of both the first screw and the second screw is 10°~12°.

3. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to claim 2, characterized in that... The thread friction angles of both the first screw and the second screw are 6° to 9°.

4. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to any one of claims 1-3, characterized in that... The flywheel nut has an outwardly extending locking part on its outer wall, and the locking assembly locks the flywheel nut by limiting and constraining the locking part.

5. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to claim 4, characterized in that... The locking part extends outward along the tangent direction of the flywheel nut's circumference.

6. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to claim 5, characterized in that... The locking assembly includes several stages of rotating shafts, each stage of which is arranged in parallel and rotatably connected to the housing. At least the other stages of rotating shafts, except for the first stage, are provided with torsion springs between themselves and the housing. Each stage of rotating shafts has a connecting rod extending radially outward, and each stage of rotating shafts has a limiting groove extending radially inward on its outer wall. The outer end of the connecting rod on each stage of rotating shafts, except for the first stage, is engaged in the limiting groove on the previous stage of rotating shaft. The outer end of the locking part is engaged in the limiting groove on the last stage of rotating shaft, thereby locking the flywheel nut with the locking assembly. The outer end of the connecting rod on the first stage rotating shaft serves as the unlocking operation end of the locking assembly.

7. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to claim 6, characterized in that... The limiting grooves on each of the rotating shafts are through grooves in the axial direction perpendicular to the corresponding rotating shaft, and the depth of the limiting grooves on each of the rotating shafts is not less than the length of the outer end portion of the corresponding locking part or the outer end portion of the connecting rod that is stuck therein.

8. The flywheel nut unlocking and separation mechanism for separating the fairing of a launch vehicle according to claim 7, characterized in that... A cylinder is fixedly installed on the outer wall of the housing. The piston rod of the cylinder extends into the housing. The outer end of the piston rod abuts against or is rotatably connected to the outer end of the connecting rod on the first-stage rotating shaft. This is used to limit and constrain the outer end of the connecting rod on the first-stage rotating shaft and to unlock the locking assembly.

9. The flywheel nut unlocking and separation mechanism for separating a launch vehicle fairing according to claim 6, characterized in that... The number of connecting rods on each of the rotating shafts is one or two. When the number of connecting rods on the rotating shaft is two, the two connecting rods are arranged in parallel and extend outward from the rotating shaft in the same direction.

10. The flywheel nut unlocking and separation mechanism for separating a launch vehicle fairing according to claim 6, characterized in that... The housing is provided with through openings, both inside and outside, for the connecting rods on each of the rotating shafts to pass through when rotating.

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