A differential preload mechanism for sleeve deployment

Abstract

The present invention discloses a differential preload mechanism for sleeve deployment, comprising an upper preload mechanism, a lower preload mechanism, a differential mechanism, and a power assembly. The input end of the differential mechanism is in transmission connection with the output end of the power assembly. The output ends of the upper and lower preload mechanisms are both equipped with drive assemblies, which drive the upper and lower preload mechanisms respectively through the differential mechanism to drive the corresponding drive assemblies into contact with the inner surface of the sleeve. The differential preload mechanism of the present invention uses a single power source to achieve variable diameter adaptation of multiple preload mechanisms, enabling the upper and lower drive assemblies to simultaneously contact the inner surface of any sleeve. While significantly increasing the effective contact force of the drive assembly, it also simplifies the structure, improves reliability, reduces the scale of the control system, and reduces costs.

Description

Technical Field

[0001] The present invention relates to the technical field of variable structure space remote sensors, and in particular to a differential pre-tightening mechanism used for sleeve deployment, which is used to effectively pre-tighten a drive assembly and the inner wall of the sleeve during the sleeve deployment process, thereby realizing the on-orbit reorganization of an ultra-large variable structure space remote sensor. Background Art

[0002] To overcome launch capacity limitations and build larger-aperture space sensors in orbit, deployable space sensors have become a new development direction. The basic principle of this technology is to systematically fold the system to reduce its footprint before launch. Once in orbit, it automatically unfolds and reassembles, achieving imaging capabilities equivalent to the designed aperture. Deployable space sensors require a deployment mechanism to achieve their desired shape. Traditional deployment mechanisms include articulated trusses, thin-walled tubes, sleeves, coils, and inflatables.

[0003] The telescopic type has good stiffness and strength performance due to the large moment of inertia of the cylinder section and the certain length of overlap retained between each two-stage cylinder. By using carbon fiber materials with a small linear expansion coefficient and mechanical limit devices, high positioning accuracy can be achieved. It is particularly suitable for the field of variable structure space cameras that require high accuracy, stability and stiffness.

[0004] Depending on the method of sleeve deployment, it can be categorized as rope-driven, screw-driven, and thin-walled open-tube-driven. Rope-driven systems offer advantages such as good deployment synchronization, simple structure and principle, and lightweight drive components. However, in microgravity, the ropes present the risk of entanglement, resulting in low reliability. The elasticity of the ropes can cause oscillations during the deployment process, making system control difficult. Screw-driven systems offer significant advantages such as a simple principle, stable structure, high strength, and high deployment driving force. However, they require very high screw machining precision and nut assembly accuracy. Limited by screw manufacturing capacity, the sleeve cannot achieve a very long single-stage extension length, resulting in a relatively low deployment-folding ratio. Screw-driven systems are prone to bending and deformation, leading to mechanism jamming and low reliability. Thin-walled open-tube-driven systems offer a high axial driving force. However, their deployment and retraction mechanisms are complex, heavy, and inconvenient. Asymmetrical deformation of the thin-walled open-tube after deployment can cause axial rotation of the sleeve, squeezing the guide mechanism and causing deformation of the deployment mechanism. Furthermore, manufacturing thin-walled open-tube systems with long travels is difficult and costly.

[0005] Based on the above technical problems, technicians in this field urgently need to develop a differential pre-tightening mechanism for sleeve deployment, which can be used to effectively pre-tighten the drive assembly and the inner wall of the sleeve during the sleeve deployment process, and realize the on-orbit reorganization of the ultra-large variable structure space remote control sensor. Summary of the Invention

[0006] The purpose of the present invention is to provide a differential pre-tightening mechanism for sleeve deployment, which is used to complete the effective pre-tightening of the drive assembly and the inner wall of the sleeve during the sleeve deployment process, and realize the on-orbit reorganization of the ultra-large variable structure space remote sensor.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a differential pre-tightening mechanism for sleeve deployment, the differential pre-tightening mechanism comprising:

[0009] A pre-tightening mechanism, wherein the pre-tightening mechanism is divided into an upper pre-tightening mechanism and a lower pre-tightening mechanism;

[0010] a differential mechanism that transmits power to the upper preload mechanism and the lower preload mechanism respectively; and

[0011] A power assembly, wherein the input end of the differential mechanism is drivingly connected to the output end of the power assembly;

[0012] The output ends of the upper pre-tightening mechanism and the lower pre-tightening mechanism are both equipped with drive assemblies, and the power assembly drives the upper pre-tightening mechanism and the lower pre-tightening mechanism respectively through the differential mechanism to drive the corresponding drive assemblies to contact the inner surface of the sleeve;

[0013] The preload mechanism, differential mechanism and power assembly are all integrated on the frame.

[0014] Furthermore, the upper pre-tightening mechanism is configured as a worm gear structure driven by the differential mechanism, and the upper pre-tightening mechanism drives the corresponding driving assembly to move via the upper pre-tightening arm;

[0015] The lower pre-tightening mechanism is configured as a worm gear structure that is driven by the differential mechanism. The lower pre-tightening mechanism drives the corresponding driving assembly to move through the lower pre-tightening arm.

[0016] Furthermore, the upper pre-tightening mechanism includes:

[0017] Two or more upper preloaded worm gears axially symmetrically distributed and rotatably connected to the frame;

[0018] The upper pre-tightening arms are axially symmetrically distributed and fixedly connected to the corresponding upper pre-tightening worm gears; and

[0019] An upper pre-tightening worm that is driven simultaneously with two or more upper pre-tightening worm wheels, and the upper pre-tightening worm is connected to the differential mechanism.

[0020] Furthermore, the lower pre-tightening mechanism includes:

[0021] Two or more lower preloaded worm gears axially symmetrically distributed and rotatably connected to the frame;

[0022] The lower pre-tightening arms are axially symmetrically distributed and fixedly connected to the corresponding lower pre-tightening worm gears; and

[0023] A lower pre-tightening worm that is driven simultaneously with two or more lower pre-tightening worm wheels, wherein the lower pre-tightening worm is connected to the differential mechanism.

[0024] Furthermore, the differential mechanism includes:

[0025] a differential shaft, the differential shaft being fixedly connected to an output end of the power assembly to be driven to rotate by the power assembly;

[0026] a first bevel gear rotatably connected to the upper end of the differential shaft; and

[0027] Rotating a third bevel gear connected to the lower middle portion of the differential shaft;

[0028] A plurality of symmetrically distributed transverse shafts protrude outward from the upper middle portion of the differential shaft, and each of the transverse shafts is rotatably connected to a second bevel gear;

[0029] The first bevel gear is meshed with a plurality of the second bevel gears simultaneously;

[0030] The third bevel gear is meshed with a plurality of the second bevel gears simultaneously.

[0031] Furthermore, the first bevel gear is fixedly connected to the upper pre-tightening worm to drive the upper pre-tightening worm to rotate;

[0032] The third bevel gear is fixedly connected to the lower pre-tightening worm to drive the lower pre-tightening worm to rotate.

[0033] Furthermore, the power assembly is a motor assembly.

[0034] In the above technical solution, the present invention provides a differential pre-tightening mechanism for sleeve deployment, which has the following beneficial effects:

[0035] The differential pre-tightening mechanism of the present invention uses a single power source to achieve variable diameter adaptation of multiple pre-tightening mechanisms, and can realize simultaneous contact between the upper and lower drive components and the inner surface of any form of sleeve. While greatly improving the effective release force of the drive component, it simplifies the structure, improves reliability, reduces the scale of the control system, and reduces costs.

[0036] The differential pre-tightening mechanism of the present invention can be used in all occasions where a drive sleeve is deployed, especially in the field of space remote sensing where high deployment accuracy is required. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0038] Figure 1 A schematic diagram of a differential pre-tightening mechanism for sleeve deployment provided in an embodiment of the present invention.

[0039] Description of reference numerals:

[0040] 1. Upper preload arm; 2. Upper preload worm; 3. Upper preload worm wheel; 4. First bevel gear; 5. Differential shaft; 6. Second bevel gear; 7. Third bevel gear; 8. Lower preload worm; 9. Lower preload worm wheel; 10. Lower preload arm; 11. Motor assembly; 12. Upper drive assembly; 13. Lower drive assembly. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0042] See also Figure 1 As shown;

[0043] A differential pre-tightening mechanism for sleeve deployment according to this embodiment includes:

[0044] Pre-tightening mechanism, the pre-tightening mechanism is divided into an upper pre-tightening mechanism and a lower pre-tightening mechanism;

[0045] A differential mechanism that transmits power to the upper preload mechanism and the lower preload mechanism respectively; and

[0046] The power assembly, the input end of the differential mechanism is drivingly connected to the output end of the power assembly;

[0047] The output ends of the upper pre-tightening mechanism and the lower pre-tightening mechanism are both equipped with drive assemblies, namely, an upper drive assembly 12 connected to the upper pre-tightening mechanism and a lower drive assembly 13 connected to the lower pre-tightening mechanism. The power assembly drives the upper pre-tightening mechanism and the lower pre-tightening mechanism respectively through the differential mechanism to drive the corresponding drive assembly to contact the inner surface of the sleeve;

[0048] The preload mechanism, differential mechanism and power components are all integrated on the frame.

[0049] Specifically, this embodiment discloses a mechanism capable of increasing the contact force with the inner surface of a sleeve, enabling the drive assembly to adapt to contact with the inner surface of sleeves of different shapes (such as sleeves with stepped, irregular, or discontinuous inner diameter variations). The mechanism includes a frame, a preload mechanism integrated into the frame, a differential mechanism, and a power assembly. The power assembly serves as a power source, driving the upper and lower preload mechanisms to move synchronously through the differential mechanism. The output ends of the upper and lower preload mechanisms are both equipped with drive assemblies, namely the aforementioned upper drive assembly 12 and lower drive assembly 13, which ultimately drive the corresponding drive assembly into contact with the inner wall of the sleeve to significantly increase the contact force.

[0050] As a further limitation of the pre-tensioning mechanism, the upper pre-tensioning mechanism of this embodiment is configured as a worm gear structure driven by a differential mechanism, and the upper pre-tensioning mechanism drives the upper drive assembly 12 to move via an upper pre-tensioning arm;

[0051] Similarly, the lower pre-tightening mechanism of this embodiment is configured as a worm gear structure driven by a differential mechanism, and the lower pre-tightening mechanism drives the lower driving assembly 13 to move via the lower pre-tightening arm.

[0052] Preferably, the upper pre-tightening mechanism of this embodiment includes:

[0053] Two or more upper preloaded worm gears 3 axially symmetrically distributed and rotatably connected to the frame;

[0054] An upper preload arm 1 that is axially symmetrically distributed and fixedly connected to the corresponding upper preload worm gear 3; and

[0055] The upper pre-tightening worm 2 is driven simultaneously with two or more upper pre-tightening worm wheels 3 and is connected to a differential mechanism.

[0056] Secondly, the lower pre-tightening mechanism of this embodiment includes:

[0057] Two or more lower preloaded worm gears 9, axially symmetrically distributed and rotatably connected to the frame;

[0058] Axisymmetrically distributed lower preload arms 10 fixedly connected to corresponding lower preload worm gears 9; and

[0059] The lower pre-tightening worm 8 is driven simultaneously with two or more lower pre-tightening worm wheels 9, and the lower pre-tightening worm 8 is connected to the differential mechanism.

[0060] The pre-tightening mechanisms of this embodiment are all worm gear structures, wherein the worm gear transmission pair of the upper pre-tightening worm wheel and the upper pre-tightening worm of this embodiment does not meet the self-locking condition; at the same time, the worm gear transmission pair of the lower pre-tightening worm wheel and the lower pre-tightening worm of this embodiment does not meet the self-locking condition.

[0061] First, this embodiment defines the structural composition of the pre-tensioning mechanism in detail; the upper pre-tensioning mechanism and the lower pre-tensioning mechanism have similar structures, and the upper pre-tensioning mechanism is taken as an example for further explanation and illustration; the upper pre-tensioning mechanism of this embodiment includes an upper pre-tensioning worm wheel 3, an upper pre-tensioning worm 2, and an upper pre-tensioning arm 1, and the upper pre-tensioning mechanism is connected to the differential assembly through the upper pre-tensioning worm 2 to drive the upper pre-tensioning worm 2 to rotate, wherein the upper pre-tensioning worm 2 and more than two upper pre-tensioning worm wheels 3 symmetrically distributed on the axis are simultaneously driven, thereby being able to drive the upper pre-tensioning worm wheel 3 to rotate at the same time, and drive the upper pre-tensioning arm 1 to move, and finally realize the driving of the drive assembly; the transmission principle of the lower pre-tensioning mechanism and the differential assembly is basically the same as that of the upper pre-tensioning mechanism, and will not be repeated here.

[0062] Preferably, the differential mechanism of this embodiment includes:

[0063] A differential shaft 5, the differential shaft 5 is fixedly connected to the output end of the power assembly to be driven to rotate by the power assembly;

[0064] Rotating the first bevel gear 4 connected to the upper end of the differential shaft 5; and

[0065] Rotate the third bevel gear 7 connected to the lower middle portion of the differential shaft 5;

[0066] A plurality of symmetrically distributed transverse shafts protrude outward from the upper middle portion of the differential shaft 5, and each transverse shaft is rotatably connected to a second bevel gear 6;

[0067] The first bevel gear 4 is meshed with multiple second bevel gears 6 at the same time;

[0068] The third bevel gear 7 is meshed with the plurality of second bevel gears 6 simultaneously.

[0069] More preferably:

[0070] The first bevel gear 4 is fixedly connected to the upper pre-tightening worm 2 to drive the upper pre-tightening worm 2 to rotate;

[0071] The third bevel gear 7 is fixedly connected to the lower pre-tightening worm 8 to drive the lower pre-tightening worm 8 to rotate.

[0072] The power assembly of this embodiment is a motor assembly 11 .

[0073] The working principle of the differential preload mechanism of this embodiment is:

[0074] The upper drive assembly 12 and the lower drive assembly 13 are mounted on one end of the upper pretensioning arm 1 and the lower pretensioning arm 10, respectively, allowing them to rotate around the pretensioning arms. When the motor assembly 11 is energized, its output rotation is transmitted to the differential consisting of the first bevel gear 4, the second bevel gear 6, and the third bevel gear 7. The properties of the differential indicate that the sum of the speeds of the first bevel gear 4 and the third bevel gear 7 equals the speed of the double differential shaft 5. When the upper and lower drive assemblies are not in contact with the inner wall of the sleeve, they are in an underdriven state. At this point, the differential, through the worm gear drive, drives the upper and lower preload arms to open irregularly. However, under the continuous drive of the motor assembly 11, the upper and lower preload arms will continue to open. When one of the drive assemblies in the upper and lower preload arms contacts the inner wall of the sleeve, the preload drive mechanism transitions to a normal driven state. The contacting preload arm ceases to move, while the non-contacting preload arm continues to move until contact is achieved. Due to another property of the differential: equal torque on both output shafts, the preload mechanism automatically distributes the contact force between the upper and lower drive assemblies and the sleeve assembly. Because the upper and lower preload arms are axially symmetrically distributed, a number greater than two provides self-centering. Because the worm gear drive does not meet the self-locking condition, the drive arm assembly can not only open under the drive of the motor assembly 11 but also retract due to the contact reaction force when the inner diameter of the sleeve changes. Furthermore, based on the initial working process of the differential, it can be concluded that the differential preload mechanism, the upper drive assembly 12 and the lower drive assembly 13 can adapt to the inner surface of the sleeve with stepped, or irregular, or discontinuous inner diameter changes, and effective contact can be ensured on these variable diameter inner surfaces, thereby providing continuous positive pressure for the expansion of the sleeve, and this positive pressure is converted into an effective driving force for the expansion of the sleeve under the movement of the drive assembly.

[0075] In the above technical solution, the present invention provides a differential pre-tightening mechanism for sleeve deployment, which has the following beneficial effects:

[0076] The differential pre-tightening mechanism of the present invention uses a single power source to achieve variable diameter adaptation of multiple pre-tightening mechanisms, and can realize simultaneous contact between the upper and lower drive components and the inner surface of any form of sleeve. While greatly improving the effective release force of the drive component, it simplifies the structure, improves reliability, reduces the scale of the control system, and reduces costs.

[0077] The differential pre-tightening mechanism of the present invention can be used in all occasions where a drive sleeve is deployed, especially in the field of space remote sensing where high deployment accuracy is required.

[0078] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A differential preload mechanism for sleeve deployment, characterized in that: The differential preload mechanism comprises: A pre-tightening mechanism, wherein the pre-tightening mechanism is divided into an upper pre-tightening mechanism and a lower pre-tightening mechanism; The differential preload mechanism also includes: a differential mechanism that transmits power to the upper preload mechanism and the lower preload mechanism respectively; A power assembly, wherein the input end of the differential mechanism is drivingly connected to the output end of the power assembly; The output ends of the upper pre-tightening mechanism and the lower pre-tightening mechanism are both equipped with drive assemblies, and the power assembly drives the upper pre-tightening mechanism and the lower pre-tightening mechanism respectively through the differential mechanism to drive the corresponding drive assemblies to contact the inner surface of the sleeve; The preload mechanism, differential mechanism, and power assembly are all integrated on the frame; The upper pre-tightening mechanism is configured as a worm gear structure driven by the differential mechanism, and the upper pre-tightening mechanism drives the corresponding drive assembly to move through the upper pre-tightening arm. The lower pre-tightening mechanism is configured as a worm gear structure driven by the differential mechanism, and the lower pre-tightening mechanism drives the corresponding drive assembly to move through the lower pre-tightening arm. The upper pre-tightening mechanism comprises: Two or more upper preloaded worm gears (3) axially symmetrically distributed and rotatably connected to the frame; The upper pre-tightening arm (1) is axially symmetrically distributed and fixedly connected to the corresponding upper pre-tightening worm gear (3); and an upper pre-tightening worm (2) that is simultaneously driven by two or more upper pre-tightening worm wheels (3), wherein the upper pre-tightening worm (2) is connected to the differential mechanism; The lower preload mechanism comprises: Two or more lower preloaded worm gears (9) axially symmetrically distributed and rotatably connected to the frame; The lower pre-tightening arm (10) is axially symmetrically distributed and fixedly connected to the corresponding lower pre-tightening worm gear (9); and a lower preload worm (8) that is driven simultaneously with two or more lower preload worm wheels (9), the lower preload worm (8) being connected to the differential mechanism; The differential mechanism comprises: A differential shaft (5), the differential shaft (5) being fixedly connected to an output end of the power assembly so as to be driven to rotate by the power assembly; a first bevel gear (4) rotatably connected to the upper end of the differential shaft (5); and Rotating a third bevel gear (7) connected to the lower middle portion of the differential shaft (5); A plurality of symmetrically distributed transverse shafts protrude outward from the upper middle portion of the differential shaft (5), and each of the transverse shafts is rotatably connected to a second bevel gear (6); The first bevel gear (4) is meshed with a plurality of the second bevel gears (6) simultaneously; The third bevel gear (7) is meshed with a plurality of the second bevel gears (6) simultaneously.

2. A differential pre-tightening mechanism for sleeve deployment according to claim 1, characterized in that: The first bevel gear (4) is fixedly connected to the upper pre-tightening worm (2) to drive the upper pre-tightening worm (2) to rotate; The third bevel gear (7) is fixedly connected to the lower pre-tightening worm (8) to drive the lower pre-tightening worm (8) to rotate.

3. A differential pre-tightening mechanism for sleeve deployment according to any one of claims 1 to 2, characterized in that: The power assembly is a motor assembly (11).

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