A device for realizing space tether cutting and tether connection

Abstract

The present invention discloses a device for space tether cutting and tether connection, which includes a tether cutting unit and a tether connection unit. The tether cutting unit includes a cutting motor, a first transmission chain, a second transmission chain, a driving arm, a clamping arm, a retractable anvil, and a cutting blade. The output shaft of the cutting motor is respectively connected to the first transmission chain and the second transmission chain. The end of the first transmission chain is connected to the driving arm, and the end of the second transmission chain is connected to the cutting blade. The clamping arm is connected to the driving arm, and the retractable anvil cooperates with the cutting blade to cut the tether. The tether connection unit includes a connection motor, a third transmission chain, a tether connector, and a slider. The output shaft of the connection motor is connected to the slider through the third transmission chain, and the slider drives the tether connector to move for tether connection.

Description

Technical Field

[0001] The present invention belongs to the technical field of space applications, and particularly relates to a device for realizing tether cutting and connection. Background Art

[0002] Ropes have the advantages of good flexibility and toughness, and have good space utilization performance. There are working conditions of cutting and connecting tethers in various space missions. However, due to the limited space of the aircraft and the limited carrying capacity of the rocket, a device for realizing tether cutting and connection with as small a volume and as light a weight as possible is required. However, there is currently no device that can complete both the functions of tether cutting and tether connection. And in the existing tether cutting schemes, there are few schemes that can realize automatic tether cutting, and the implementation methods of the only available schemes are also relatively complex. The existing tether connection schemes are all that the tether is first fixed on two structural members, and the connection of the tether is realized through the connection of the structural members, which is difficult to meet the requirements of the tether for space missions. Summary of the Invention

[0003] The technical problem solved by the present invention is: overcoming the deficiencies of the prior art, the present invention proposes a device for realizing tether cutting and connection, which has a simple structure and can reliably realize tether cutting and connection.

[0004] The present invention is realized by the following technical solutions:

[0005] A device for realizing space tether cutting and tether connection includes a tether cutting unit and a tether connection unit;

[0006] The tether cutting unit includes a cutting motor, a first transmission chain, a second transmission chain, a driving arm, a clamping arm, a retractable anvil, and a cutting blade; the output shaft of the cutting motor is respectively connected to the first transmission chain and the second transmission chain, the end of the first transmission chain is connected to the driving arm, and the end of the second transmission chain is connected to the cutting blade; the clamping arm is connected to the driving arm, and the clamping arm has a degree of freedom of horizontal rotation relative to the driving arm; the retractable anvil cooperates with the cutting blade to cut the tether.

[0007] The tether connection unit includes a connection motor, a third transmission chain, a tether connector, and a slider. The output shaft of the connection motor is connected to the slider through the third transmission chain, and the slider drives the tether connector to move for tether connection.

[0008] Preferably, the retractable anvil is a movable component, with springs connected to both ends, and a groove in the middle with a length longer than the cutting blade and a height higher than the cutting blade; when not cutting, the cutting blade is in the groove; when cutting, the retractable anvil is pressed by the clamping arm to expose the cutting blade and cut the tether.

[0009] Preferably, the retractable anvil has two U-shaped holes, and two screws respectively pass through the two U-shaped holes and are fixed on the device to limit the movement of the retractable anvil.

[0010] Preferably, the tether cutting unit further includes a first eccentric wheel located on the second transmission chain; the cutting blade includes a connecting rod and a blade fixedly connected, and the connecting rod is provided with a U-shaped hole; the outer extension rod of the first eccentric wheel passes through the U-shaped hole, and the rotation of the eccentric wheel drives the connecting rod and the blade to reciprocate.

[0011] Preferably, the tether cutting unit further includes a hysteresis clutch located on the first transmission chain; the slip torque value of the hysteresis clutch is less than the torque value when the locked-rotor torque of the cutting motor is transmitted to the hysteresis clutch through the transmission chain, so as to protect the cutting motor.

[0012] Preferably, the driving arm and the clamping arm are connected by screws. The driving arm and the clamping arm are both provided with through holes. The screw passes through the two through holes and is fixed on the driving arm, so that the clamping arm has the freedom to rotate horizontally around the center of the screw relative to the driving arm.

[0013] Preferably, the tether connecting piece includes a connecting rod and a connecting piece sleeve capable of relative movement, and is used for connecting the first tether to be connected and the second tether to be connected;

[0014] There are two rope-passing through holes between the head and the tail of the connecting rod. The head rope-passing through hole is used for fixedly connecting with the first tether to be connected, and the tail rope-passing through hole is used for passing the second tether to be connected through;

[0015] The connecting piece sleeve is provided with a through hole for passing the rope. The second tether to be connected passes through the tail rope-passing through hole of the connecting rod and the through hole of the connecting piece sleeve in sequence; the gap between the connecting rod and the connecting piece sleeve is less than the minimum diameter of the second tether to be connected after being compressed;

[0016] The head of the connecting rod is connected with the slider and slides along the direction away from the connecting piece sleeve under the drive of the slider. The second tether to be connected is pressed between the connecting rod and the connecting piece sleeve under the frictional force of the connecting rod and the connecting piece sleeve.

[0017] Preferably, the surface of the connecting rod relative to the connecting piece sleeve is provided with patterns for increasing friction.

[0018] Preferably, the tether connecting unit further includes a tether connecting piece and a slider. The tether connecting piece is connected to the third transmission chain through the slider; the two tether connecting pieces are denoted as the first tether connecting piece and the second tether connecting piece;

[0019] A bidirectional transmission gear is installed in the third transmission chain. When the connecting motor rotates forward, it drives the first tether connecting piece, and when it rotates backward, it drives the second tether connecting piece.

[0020] Preferably, it further includes a mounting plate, and the driving arm, the clamping arm, the retractable anvil, the cutting blade, the tether connecting piece, and the slider are all placed on the mounting plate.

[0021] The present invention has the following beneficial effects compared with the prior art:

[0022] 1) The present invention integrates the functions of tether cutting and tether connection on one device. The overall weight of the device is less than 2.3 kg, and the envelope size is less than 170 mm × 170 mm × 180 mm, with small size and light weight.

[0023] 2) The present invention uses large friction to achieve reliable connection of the tether without the need for tight connection between structural components. At the same time, the tether can perform functions such as retracting, unwinding, and despinning before connection to complete on-orbit tasks.

[0024] 3) The present invention adds a hysteresis clutch to the transmission chain of the tether cutting unit to avoid the problem of motor stalling caused by excessive torque during the tether cutting process.

[0025] 4) The present invention uses a bidirectional gear in the transmission chain of the tether connection unit, so that the two rotation directions of the motor are respectively connected to two connecting pieces to achieve reliable connection. At the same time, it effectively reduces the complexity of the circuit board and avoids the problem that the device is prone to failure due to being too precise and complex. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of a device for realizing space tether cutting and tether connection according to an embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of the tether cutting unit according to an embodiment of the present invention;

[0028] Figure 3 It is a schematic diagram of the tether connection unit according to an embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of the mounting plate according to an embodiment of the present invention;

[0030] Figure 5 It is a schematic diagram of the transmission chain of the tether cutting unit according to an embodiment of the present invention;

[0031] Figure 6 It is a schematic diagram of the retractable anvil according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] For the convenience of understanding the embodiments of the present invention, the following will further explain with specific embodiments by combining the drawings, and the embodiments do not constitute a limitation to the embodiments of the present invention.

[0033] An embodiment of a space tether cutting and connecting device of the present invention is as Figure 1As shown, the device 100 includes a tether cutting unit 200 and a tether connecting unit 300, which respectively realize cutting and connecting of the tether.

[0034] (1) Tether cutting unit

[0035] The structure of the tether cutting unit 200 is as follows: Figure 2 As shown, it includes a cutting motor 201 , a driving arm 402 , a clamping arm 403 , a hysteresis clutch 202 , a retreat anvil 404 , a cutting blade assembly 405 , and a first eccentric wheel 203 .

[0036] The cutting blade assembly 405 includes a connecting rod and a blade. The blade connecting rod and the blade are fixedly connected by screws, and a U-shaped hole is provided on the blade connecting rod.

[0037] The retreating knife anvil 404 is a movable part, such as Figure 6 As shown, springs are connected at both ends. The springs should have a suitable preload force, and the preload force value is based on the ability to compress the tether. There is a slot in the middle of the yield anvil that is longer than the blade and higher than the blade, and the blade passes through the slot. When not working, the blade is in the yield anvil slot and is protected by the yield anvil. When working, the yield anvil is pushed by the clamping arm to expose the blade and cut the tether. The yield anvil has two U-shaped holes, and two screws pass through the two U-shaped holes and are fixed to the device, which limits the movement of the yield anvil.

[0038] The output shaft of the cutting motor 201 is connected to two transmission chains, such as Figure 5 As shown, a first eccentric wheel 203 is installed on the output end of one of the transmission chains; a hysteresis clutch 202 is provided on the other transmission chain, and the output end of the transmission chain is connected to the driving arm 402.

[0039] The extension rod of the first eccentric wheel 203 passes through the U-shaped hole of the connecting rod of the cutting blade 405. The rotation of the eccentric wheel drives the connecting rod of the blade to reciprocate, and the blade reciprocates accordingly.

[0040] The driving arm 402 and the clamping arm 403 are connected by screws and gaskets. The screws pass through the through holes of the driving arm and the clamping arm and are finally fixed on the driving arm, so that the clamping arm 403 has the freedom to rotate horizontally around the center of the screw relative to the driving arm 402. The gasket is used to adjust the height of the clamping arm 403 so that the cutting blade 405 is at the same height as the center of the clamping arm.

[0041] The hysteresis clutch 202 is used to protect the cutting motor 201. When the torque of the cutting motor 201 increases to the set value, the hysteresis clutch 202 will slip and maintain the current torque. This set value should be less than the torque value when the locked-rotor torque of the cutting motor is transmitted to the hysteresis clutch through the transmission chain, and greater than the torque value when the driving arm 402 drives the clamping arm to drive the tether to press against and retreat the anvil 404 to the limit position. The maximum force generated during the working process of the two springs of the retreating knife felt should be less than the force value calculated to the output end by the slipping torque of the hysteresis clutch through the transmission chain.

[0042] (2) Tether connection unit

[0043] The structure of the tether connection unit 300 is as Figure 3 shown, and it includes a connecting motor, a first tether connecting member, a second tether connecting member, a first slider, a second slider, a second eccentric wheel, and a third eccentric wheel.

[0044] The tether connecting member includes a connecting rod, a connecting member sleeve, and a bracket. The connecting rod has patterns for increasing friction. In this example, the shape of the pattern is a washboard shape, and the specific depth and width depend on the specific tether state. When tether connection needs to be achieved, the second eccentric wheel or the third eccentric wheel drives the corresponding slider to move. The connecting rod slides along the direction away from the connecting member sleeve under the drive of the slider, while the connecting member sleeve cannot move due to being limited by the connecting member bracket. In the initial state, the tether passes through the rope-passing holes of the connecting member sleeve and the connecting rod. After the slider starts to move, relative movement occurs between the connecting rod and the connecting member sleeve, and a section of the tether enters the gap between the connecting rod and the connecting member sleeve. Due to the unilateral gap between the connecting rod and the connecting member sleeve and the patterns on the connecting rod, a large friction force will be generated between the tether and the connecting member, preventing the tether from slipping out.

[0045] The output shaft of the connecting motor is connected to the transmission chain. There is a two-way transmission gear in the transmission chain, which can drive the tether connecting member 1 when the connecting motor rotates forward and drive the tether connecting member 2 when it rotates backward. The tether connecting member 1 and the tether connecting member 2 serve as backups for each other. If one connection fails, the other can be connected. If one connection is successful, the other can also complete the next task.

[0046] The end of the transmission chain is connected to the slider. When the slider moves, it drives the connecting rod to move. The connecting member sleeve is limited, and the relative movement between the connecting rod and the connecting member sleeve brings the tether into the gap between the connecting rod and the connecting member sleeve, realizing a self-locking connection; the other tether is tied to the head of the connecting rod, realizing the connection of the two tethers.

[0047] In this embodiment, an installation plate 400 is provided in the device, as Figure 4As shown in the figure, a slider 401, a driving arm 402, a clamping arm 403, a retractable anvil 404, a cutting blade 405, a spring 406, a first tether connecting member 407, and a second tether connecting member 408 are installed on the mounting plate. The spatial arrangement of the cutting blade 405 and the tether connecting member in the vertical direction is as follows: the cutting blade 405 is higher than the first tether connecting member 407, and the first tether connecting member 407 is higher than the second tether connecting member 408. The tether through-holes of the first tether connecting member 407 and the second tether connecting member 408 are concentric in the vertical direction.

[0048] The cutting motor 201, the hysteresis clutch 202, and the first eccentric wheel 203 of the drive part 101 of the tether cutting unit, and the connecting motor 301, the second eccentric wheel 302, and the third eccentric wheel 303 of the drive part 102 of the tether connecting unit are all placed at the lower end of the mounting plate.

[0049] The working principle of the present invention is as follows:

[0050] The initial position of the tether to be cut is at the center of the mounting plate, and the direction is 70° with respect to the surface of the mounting plate. Because the on-orbit mission is being carried out, the upper extension length and the lower penetration length can be considered infinitely long relative to this device, and there will be no phenomenon of the tether escaping. When cutting the tether, the cutting motor 201 drives the driving arm 402 to rotate counterclockwise (viewed from top to bottom). During the rotation process, it will push the clamping arm 403 to drive the tether to be pressed against the retractable anvil 404. The clamping arm 403 presses the tether, and the tether presses the retractable anvil 404. The retractable anvil 404 has a spring 406 to provide a pre-tightening force to press the tether. After the retractable anvil 404 is pressed, the cutting blade 405 will be exposed. The cutting blade reciprocates under the drive of the cutting motor 201. After cutting the tether at a predetermined time, the clamping arm resets.

[0051] Among the two tethers to be connected, one passes through the through-holes of the connecting member sleeve and the connecting rod, with the upper end exposed by 10 - 20 mm and the lower end exposed length being considered infinitely long relative to this device. The other is tied to the head of the connecting rod. When connecting the tethers, the tether connecting member 1 is used for the first tether connecting task. If the tether connecting member 1 fails to work, then the tether connecting member 2 is used for tether connection. The second tether connecting task uses the tether connecting member 2 to work. The connection processes of the two tether connecting members are the same. The connecting motor 301 drives the slider 401 through a transmission chain. The slider drives the connecting rod to move, while the connecting member sleeve is limited. The relative movement of the connecting rod and the connecting member sleeve brings the tether into the gap between the connecting rod and the connecting member sleeve, and the relative static state of the connecting rod and the connecting member sleeve is maintained through frictional self-locking. The other tether is kept relatively stationary with the connecting rod by tying a knot at the head of the connecting rod, thereby realizing the connection of the tethers.

[0052] In the present invention, there is no requirement for the sequence of tether cutting and tether connection. In practical applications, the sequence depends on specific working requirements.

[0053] Although the present invention has been disclosed above in its preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention all fall within the protection scope of the technical solution of the present invention.

[0054] The content not detailedly described in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims

1. A device for realizing space tether cutting and tether connection, characterized in that It includes a tether cutting unit and a tether connecting unit; The tether cutting unit includes a cutting motor, a first drive chain, a second drive chain, a driving arm, a clamping arm, a retractable anvil, and a cutting blade; the output shaft of the cutting motor is respectively connected to the first drive chain and the second drive chain, the end of the first drive chain is connected to the driving arm, and the end of the second drive chain is connected to the cutting blade; the clamping arm is connected to the driving arm, and the clamping arm has a degree of freedom of horizontal rotation relative to the driving arm; the retractable anvil cooperates with the cutting blade to cut the tether; The tether connecting unit includes a connecting motor, a third drive chain, a tether connector, and a slider. The output shaft of the connecting motor is connected to the slider through the third drive chain, and the slider drives the tether connector to move for tether connection; The retractable anvil is a movable part, with springs connected to both ends respectively, and a groove in the middle that is longer in length and higher in height than the cutting blade; when not cutting, the cutting blade is in the groove; when cutting, the retractable anvil is pressed by the clamping arm, exposing the cutting blade to cut the tether.

2. The device for realizing space tether cutting and tether connection according to claim 1, wherein The retractable anvil has two U-shaped holes, and two screws pass through the two U-shaped holes and are fixed on the device to limit the movement of the retractable anvil.

3. A device for realizing space tether cutting and tether connection according to claim 1, characterized in that, The tether cutting unit further includes a first eccentric wheel located on the second drive chain; the cutting blade includes a connecting rod and a blade fixedly connected, and the connecting rod is provided with a U-shaped hole; the extension rod of the first eccentric wheel passes through the U-shaped hole, and the rotation of the eccentric wheel drives the connecting rod and the blade to perform reciprocating motion.

4. A device for realizing space tether cutting and tether connection according to claim 1 or 3, characterized in that The tether cutting unit further includes a hysteresis clutch located on the first drive chain; the slipping torque value of the hysteresis clutch is less than the torque value when the locked-rotor torque of the cutting motor is transmitted to the hysteresis clutch through the drive chain, realizing the protection of the cutting motor.

5. A device for realizing space tether cutting and tether connection according to claim 1, characterized in that, The driving arm and the clamping arm are connected by screws. The driving arm and the clamping arm are both provided with through holes. The screws pass through the two through holes and are fixed on the driving arm, so that the clamping arm has a degree of freedom of horizontal rotation relative to the driving arm around the center of the screw.

6. The device for realizing space tether cutting and tether connection according to claim 1, characterized in that, The tether connector includes a connecting rod and a connector sleeve that can perform relative motion, and is used to connect the first tether to be connected and the second tether to be connected; There are two rope-passing through holes between the head and the tail of the connecting rod. The head rope-passing through hole is used for fixedly connecting with the first tether to be connected, and the tail rope-passing through hole is used for passing the second tether to be connected through; The connector sleeve is provided with a through hole for passing the rope. The second tether to be connected passes through the tail rope-passing through hole of the connecting rod and the through hole of the connector sleeve in sequence; the gap between the connecting rod and the connector sleeve is less than the minimum diameter of the second tether to be connected after being compressed; The head of the connecting rod is connected to the slider and slides in the direction away from the connector sleeve under the drive of the slider. The second tether to be connected is pressed between the connecting rod and the connector sleeve under the frictional force of the connecting rod and the connector sleeve.

7. The device for realizing space tether cutting and tether connection according to claim 6, characterized in that, The surface of the connecting rod relative to the connector sleeve is provided with patterns for increasing friction.

8. The device for realizing space tether cutting and tether connection according to claim 1, characterized in that, The tether connecting unit further includes a tether connector and a slider. The tether connector is connected to the third drive chain through the slider; the two tether connectors are denoted as the first tether connector and the second tether connector; A two-way transmission gear is installed in the third transmission chain, which drives the first tether connecting member when the motor rotates forward and drives the second tether connecting member when the motor rotates backward.

9. The device for realizing space tether cutting and tether connection according to claim 1, characterized in that It further includes a mounting plate, and the driving arm, the clamping arm, the retractable anvil, the cutting blade, the tether connecting member, and the slider are all placed on the mounting plate.

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