Self-unlocking and self-buffering rotary locking type multi-section drag reduction rod and performance test method

Abstract

A self-unlocking and self-buffering rotary locking type multi-section drag reduction rod relates to the field of spacecraft structures and comprises an outer shell, a middle shell set, an inner shell, a fuel gas generator, a self-unlocking assembly and a chassis, the middle shell set is located in the outer shell, the inner shell is located in the middle shell set, and the middle shell set comprises a plurality of shell bodies which are sequentially connected in a sleeved mode; in the outer shell, the shell and the inner shell, any two adjacent shells form an outer shell and an inner shell, the top of the inner wall of the outer shell is provided with a protruding inner ring section, and the inner ring section is provided with a plurality of rotating U-shaped grooves in the circumferential direction; cylindrical guide pins are arranged on the outer wall face of the inner shell and matched with the rotating U-shaped grooves in a one-to-one mode, the base plate is fixedly connected to the bottom of the outer shell, the fuel gas generator is connected to the middle of the base plate and extends into the inner shell, and the self-unlocking assembly is arranged at the position of an outlet of the fuel gas generator so that the outlet of the fuel gas generator can be opened after the self-unlocking assembly is unlocked. The problems of large unlocking impact, large in-place impact and overlarge gap of a locking structure of an existing multi-section unfolding and locking anti-drag rod structure are solved.

Description

Technical Field

[0001] The present application belongs to the field of spacecraft structure technology, and provides a self-unlocking, self-buffering, retractable multi-section drag reduction rod and a corresponding performance test method. Background Art

[0002] The head cover of the spacecraft launched underwater adopts a blunt head shape with a hydrodynamic shape, and a pneumatic drag reduction rod formed by a retractable multi-section rod is used at the top of the aircraft to form a virtual cone, which is a technical method for pneumatic load reduction after exiting the water. The telescopic rod structure proposed in the patent "A high-frequency, high-damping multi-body cantilever telescopic rod structure with a top plate", application number 202318008466.6, is the highest level at home and abroad at present, but it uses the method of holding pressure to cut the locking pin for unlocking, and there is no buffer structure, and uses steps and large deformation hook claw groups to achieve in-place stop and lock. The corresponding structure has a large holding pressure section before deployment, resulting in a large unlocking impact, too fast deployment speed, large in-place impact and a large stop gap after locking. Excessive in-place impact has a great impact on the device body, the pyrotechnics that continuously replenish air, and the nearby sensitive sensors, which may cause problems such as unsustainable combustion of the pyrotechnics and damage to the sensors. Excessive stop gap will cause the system stiffness to be highly sensitive to the load size. Summary of the invention

[0003] The technical problem solved by the present application is: to overcome the deficiencies of the prior art, to provide a self-unlocking, self-buffering, retractable multi-section drag reduction rod and a corresponding performance test method, to solve the problems of large unlocking impact, large impact in position, and excessive gap in the locking structure in the existing multi-section unfolded and locked drag reduction rod structure.

[0004] The device has reliable locking function, and can achieve unlocking first and then deployment without holding back pressure by only using driving high-pressure gas, and uses internal structure to achieve compressed gas self-buffering and rotation locking. It has the advantages of fast unlocking, small unlocking impact, small impact in place, reliable locking, compact locking structure, high system stiffness and insensitivity to load, and easy disassembly. At the same time, it provides a test method for repeatable inspection of unlocking, deployment, locking, sealing performance and modal damping characteristics.

[0005] The technical solutions provided by this application are as follows:

[0006] A self-unlocking and self-buffering rotary locking multi-section drag reduction rod, comprising an outer shell, an intermediate shell group, an inner shell, a gas generator, a self-unlocking component, an anti-reverse rotation component and a chassis, wherein the intermediate shell group is located inside the outer shell, and the inner shell is located inside the intermediate shell group, and the intermediate shell group comprises a plurality of shells which are sleeved in sequence; any two adjacent ones of the outer shell, the shell and the inner shell form an outer shell and an inner shell, and a raised inner ring segment is provided on the top of the inner wall of the outer shell, and a plurality of rotating U-grooves are provided on the inner ring segment along the circumferential direction, and the rotating U-groove comprises a semicircular segment and a horizontal straight segment, and the semicircular segment is an arc-shaped groove with a central angle of 90 degrees, and one end of the semicircular segment penetrates through the bottom edge of the inner ring segment and is perpendicular to the bottom edge of the inner ring segment, and the other end of the semicircular segment is connected to the horizontal straight segment, and the horizontal straight segment It extends circumferentially along the inner ring segment; a cylindrical guide pin is provided on the outer wall of the inner shell, and the cylindrical guide pin matches the rotating U-groove one by one; a raised outer ring segment is provided at the bottom of the outer wall of the inner shell, and the outer ring segment is provided with an axially distributed sealing ring groove, and the sealing ring groove is used to place the O-ring; the chassis is fixedly connected to the bottom of the inner shell, the shell and the inner shell are located above the chassis, the gas generator is fixedly connected to the middle of the chassis and extends into the inner shell, and the self-unlocking component is arranged at the outlet position of the gas generator, so that the outlet of the gas generator is opened after the self-unlocking component is unlocked; the anti-reverse rotation component is installed on the inner ring segment and is located at the junction of the semicircular segment and the horizontal and vertical segment, so that after the cylindrical guide pin enters the horizontal and vertical segment, the cylindrical guide pin is locked in the horizontal and vertical segment.

[0007] A plurality of air-guiding U-grooves are provided at the bottom of the inner wall surface of the inner ring section, and throttling air leakage holes are provided at the upper part of the air-guiding U-grooves, and the throttling air leakage holes are connected to the inner and outer sides of the external shell.

[0008] The inner ring segment is provided with an anti-reverse rotation component mounting hole, and the anti-reverse rotation component mounting hole includes a threaded hole at the top and a square hole at the bottom. The anti-reverse rotation component includes a clamping pin and a square tongue. The clamping pin is a rotary step shaft structure, and its upper part is a threaded column, and its lower part is an elastic push rod. The upper part of the square tongue is a positioning disk, and the lower part is a square columnar tongue body. The lower end face of the tongue body is a wedge-shaped inclined surface. Along the circumferential direction of the inner ring segment, the end of the inclined surface close to the semicircular segment is lower than the end close to the horizontal segment. The tongue body passes through the square hole, and the positioning disk is located above the square hole. The threaded column is threadedly connected to the threaded hole, and the elastic push rod is in contact with the positioning disk.

[0009] One end of the semicircular segment that passes through the bottom edge of the inner ring segment is the entrance end, and rounded corners are arranged on both sides of the entrance end.

[0010] The gas generator is provided with an ignition chamber, a combustion chamber, a gas channel and a valve seat chamber in sequence from the bottom to the top. The combustion chamber is provided with a gunpowder block. The gunpowder block generates a large amount of high-temperature gas when burning. The ignition chamber is used to install an ignition device to ignite the gunpowder block. The valve seat chamber extends to the top of the gas generator. A plurality of evenly distributed air outlets are arranged in the circumference of the valve seat chamber. The axes of the air outlets are along the radial direction of the gas generator and extend to the outer wall of the gas generator. The self-unlocking component is installed in the valve seat chamber. The high-temperature gas generated by the combustion of the gunpowder block enters the self-unlocking component in the valve seat chamber through the gas channel. When the self-unlocking component is opened, the air outlet is opened.

[0011] The self-unlocking component includes a pull rod, a hook, a ring frame, a valve core push rod, a hook shaft and a sealing cover. A cross partition is provided in the inner shell, and the gas generator is located on the side of the cross partition facing the chassis. One end of the pull rod is connected to the cross partition, and the other end of the pull rod is a lower end plate, which is used to connect the hook; the ring frame is threadedly connected to the circumferential surface of the inner wall of the valve seat cavity, and the ring frame is provided with a plurality of ventilation holes that are directly opposite to the air outlet holes. The upper part of the ring frame is a cross-shaped hook fixing groove, and the ring frame is provided with a middle end plate and a valve core cavity in sequence below the hook fixing groove. A head positioning through hole is provided at the axial position of the middle end plate, and the head positioning through hole connects the hook fixing groove with the valve core cavity; the valve core push rod includes a straight column section, a push rod and a valve core body that are connected in sequence. The end of the straight column section away from the push rod is a spherical head surface, and the end of the valve core body away from the push rod is provided with a There is a recessed groove, the valve core body is located in the valve core cavity, the top of the straight column section passes through the top head positioning hole and extends into the center position of the hook claw fixing groove, and the limit ring is arranged between the valve core body and the middle end plate; one end of the hook claw is located in the hook claw fixing groove and is rotatably connected to the ring frame so that the top of the hook claw can be close to or away from the axis of the valve core push rod, and the hook claw is provided with a retaining surface, an inwardly inclined conical surface and a claw head from bottom to top on the side facing the axis of the valve core push rod. When the retaining surface fits with the straight column section, the claw head is hooked on the upper surface of the lower end plate; along the direction away from the retaining surface, the inwardly inclined conical surface gradually approaches the axis direction of the valve core push rod relative to the plane where the retaining surface is located, and as the valve core push rod moves upward, the ball head surface contacts the inwardly inclined conical surface and gradually pushes the hook claw to rotate, so that the top of the hook claw can move away from the axis direction of the valve core push rod.

[0012] The pull rod comprises a threaded section, a positioning ring, a pull rod body and a lower end plate which are sequentially arranged axially of the salt itself. The positioning ring is located on the side of the diaphragm facing the bottom plate. The end of the threaded section passing through the diaphragm is threadedly connected with a sealing gland.

[0013] When installing the self-unlocking component, install the hook in the hook fixing groove of the ring frame, install the limit ring and the valve core push rod into the valve core cavity, and make the claw head hold and press the lower end plate, install the ring frame with the limit ring and the valve core push rod into the valve seat cavity, install the gas generator on the chassis, and make the threaded section of the pull rod pass through the cross partition, connect the sealing cover with the threaded section, and tighten the pull rod to form axial preload.

[0014] The chassis is a revolving ring structure, the middle of which is a cylindrical structure, the inner wall of the cylindrical structure is provided with threaded holes, the top of the cylindrical structure is an inverted ring, a sealing disk is provided on the outer circumferential surface of the gas generator, a sealing ring groove is provided on the upper end surface of the sealing disk, the inverted ring is clamped in the sealing ring groove, and the cylindrical structure is threadedly connected with an anti-loosening pressure ring and a threaded pressure ring in sequence through a threaded hole on the side of the sealing disk away from the inverted ring.

[0015] A performance test method for a self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod, including an inflation and deployment test and a non-contact modal test;

[0016] The inflation deployment test includes: the drag reduction rod is fixed on the test bracket through the outer shell, and an inflation tool is installed in the middle of the chassis of the drag reduction rod. The structure of the inflation tool is consistent with the gas generator and the self-unlocking component. No gunpowder is installed inside the inflation tool. The inflation tool is connected to the gas source through an inflation passage. The inflation passage is sequentially connected with a switch F1 and a pressure measuring device along the airflow charging direction. The inflation passage is connected with an air release passage between the switch F1 and the pressure measuring device, and the air release passage is connected with a switch F2. Compressed air or nitrogen is filled into the drag reduction rod. When the drag reduction rod begins to unlock, the pressure inside the drag reduction rod is recorded by the pressure measuring device, which is the unlocking pressure value Pj. After the drag reduction rod begins to deploy, continue to slowly fill it with compressed air or nitrogen without releasing the pressure until the drag reduction rod is fully deployed, and record the pressure change process during the deployment process and the pressure value inside the drag reduction rod when it is fully deployed; continue to fill it with compressed air or nitrogen until the pressure inside the drag reduction device reaches the set pressure P0, close the inflation passage F1 and the deflation passage F2, and perform an airtightness inspection test on the drag reduction device. During the test time of the airtightness inspection test, continue to record the pressure change inside the drag reduction device. No pressure change indicates that the airtightness performance is good;

[0017] The non-contact modal test includes: the drag reduction rod in the unfolded state is fixed on the test bracket through the shell, and the rod is inflated to the set pressure P0 through the inflation tool. Then, the excitation device is used to sweep the frequency according to the random vibration process, and the laser micro-distance measuring instrument is used to measure the vibration micro-displacement process of the characteristic position of the drag reduction rod. Several modes are measured by the correlation between the change of vibration amplitude and frequency, and then the modal judgment criterion MAC is used to analyze the correlation between modal vibration shapes. The first-order frequency value f1 is determined according to the first frequency value of the drag reduction rod to generate resonance, and then the excitation device is used to excite on both sides of the narrow band f1 frequency in a sinusoidal vibration mode to determine the exact value of f1.

[0018] The advantages of the present invention are:

[0019] (1) The locking function of the device is reliable, and only high-pressure driving gas is used to achieve unlocking first and then deployment without pressure holding, which has the advantages of fast unlocking and small unlocking impact.

[0020] (2) The internal structure is used to achieve compressed air self-buffering and rotation locking, which has the advantages of small impact in place and reliable locking;

[0021] (3) The locking structure is compact, with no gap in both directions, and the overall rigidity of the system is high and insensitive to load;

[0022] (4) The use of an exposed and easily disassembled anti-reverse rotation component can conveniently realize the device re-disassembly and facilitate reuse.

[0023] (5) A complete set of test methods is provided for repeatable testing of unlocking, deployment, locking, sealing performance and modal damping characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of a self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod;

[0025] Figure 2 This is the schematic diagram of the shell structure;

[0026] Figure 3 It is the structural principle diagram of the intermediate shell group;

[0027] Figure 4 This is the schematic diagram of the inner shell structure;

[0028] Figure 5 This is the structural principle diagram of the gas generator;

[0029] Figure 6 It is the structural principle diagram of threaded pressing ring, locking pressing ring and tightening tooling;

[0030] Figure 7 This is the structural schematic diagram of the self-unlocking component;

[0031] Figure 8 This is the schematic diagram of the pull rod structure;

[0032] Fig. 9 This is the principle diagram of the hook structure;

[0033] Fig.10 This is the principle diagram of the ring frame structure;

[0034] Fig.11 This is the principle diagram of the valve core push rod structure;

[0035] Fig.12 It is the principle diagram of the limiting ring structure;

[0036] Fig.13 This is the principle diagram of the sealing gland structure;

[0037] Fig.14 This is the working principle diagram of the self-unlocking component;

[0038] Fig.15This is the structure and working principle diagram of the anti-reverse rotation component;

[0039] Fig.16 This is the principle diagram of the inflation deployment test method;

[0040] Fig.17 This is the schematic diagram of the non-contact modal test method. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0042] The present application embodiment discloses a self-unlocking and self-buffering rotary locking multi-section drag reduction rod, such as Figure 1 As shown, it is composed of an outer shell 1, an intermediate shell group 2, an inner shell 3, a gas generator 4, a self-unlocking component 5, an anti-reverse rotation component 6, a chassis 7, a threaded pressure ring 8 and an anti-loosening pressure ring 9.

[0043] like Figure 2 As shown, the outer shell 1 is a rotating body structure, with the upper part being a flange disk surface 1.1 and the lower part being a barrel section 1.2. Sixteen rotating U-grooves 1.3 are arranged on the inner side of the upper part of the barrel section. The rotating U-groove is composed of a semicircular section and a horizontal and vertical section, and large fillets are arranged on both sides of the entrance part. On the upper part of the barrel section, on the lower structure of the rotating U-groove, four air guide U-grooves 1.4 are arranged on the inner side, and four throttling air leakage holes 1.5 are arranged on the upper part of the air guide U-groove to connect the inside and outside of the outer shell. On the inner side of the flange disk surface, at the intersection of the semicircular section and the horizontal and vertical section of the four rotating U-grooves, an anti-reverse rotation component mounting hole is arranged, including an upper M3 threaded hole 1.6 and a lower square hole 1.7.

[0044] like Figure 3 As shown, the intermediate shell group 2 includes 7 mutually fitted shells, and their structures are basically the same, all of which are rotating sleeve structures, and only the inner and outer diameters are mutually matched. The intermediate shell structure includes a sleeve section 2.1, an upper inner ring section 2.4 and a lower outer ring section 2.2. Two axially distributed sealing ring grooves 2.3 are arranged on the outer circumference of the outer ring section 2.2 to place O-rings to form a double-layer sealing structure. The inner ring section 2.4 is provided with a circumferentially uniformly distributed rotating U groove 2.7, which is composed of a semicircular section and a horizontal and vertical section, and large fillets are arranged on both sides of the inlet. From the outside to the inside, the number of rotating U grooves arranged in each intermediate shell is 16, 16, 12, 12, 8, 8, and 6 respectively, and the number is mainly determined according to the load-bearing conditions and structural parameters of each section. Outside the rotating U groove of the inner ring section, 4 air guide throttling and pressure relief structures 2.6 are arranged on the inside. At the top, the anti-reverse rotation assembly mounting hole 2.5 is set at the intersection of the upper semicircular section and the horizontal section of the four rotating U grooves. Evenly distributed cylindrical guide pins 2.8 are set on the outer peripheral surface of the lower part of the sleeve section. The number of cylindrical guide pins 2.8 is consistent with the number of rotating U grooves on the outer matching shell section.

[0045] like Figure 4 As shown, the inner shell 3 is a rotary sleeve structure. The middle of the upper part of the outer shell 3.1 is a transverse partition 3.3, which separates the upper and lower chambers. The lower chamber accommodates the gas generator and participates in forming the sealing chamber of the device. The middle of the transverse partition is a through hole 3.4, which is used to connect the pull rod of the self-unlocking component 5. Six cylindrical guide pins 3.5 are evenly distributed on the outer circumference of the middle and lower part. The bottom is an outer ring section 3.6, and two axially distributed sealing ring grooves 3.7 are set on the outer circumference of the outer ring section.

[0046] In summary, the above structure can be described as: among the outer shell 1, the shell and the inner shell 3, any two adjacent ones form an outer shell and an inner shell, a raised inner ring segment is provided on the top of the inner wall of the outer shell, and a plurality of rotating U-grooves are provided on the inner ring segment along the circumferential direction, and the rotating U-groove includes a semicircular segment and a horizontal vertical segment, and the semicircular segment is an arc groove with a central angle of 90 degrees, one end of the semicircular segment penetrates to the bottom edge of the inner ring segment and is perpendicular to the bottom edge of the inner ring segment, and the other end of the semicircular segment is connected to the horizontal vertical segment, and the horizontal vertical segment extends circumferentially along the inner ring segment; a cylindrical guide pin is provided on the outer wall of the inner shell, and the cylindrical guide pin is matched with the rotating U-groove one by one, a raised outer ring segment is provided on the bottom of the outer wall of the inner shell, and the outer ring segment is provided with an axially distributed sealing ring groove, and the sealing ring groove is used to place an O-ring. The difference between the inner diameter of the top of the outer shell and the outer diameter of the top of the inner shell is less than 0.01 mm, so that the gas between two adjacent outer shells and inner shells is difficult to be discharged from the gap therebetween. Therefore, a throttling air leakage hole is further provided so that the gas between the outer shell and the inner shell can be further discharged through the throttling air leakage hole.

[0047] like Figure 5 As shown, the gas generator 4 is a rotary tube structure. The lower middle part is a combustion chamber 4.2, in which a built-in gunpowder block generates a large amount of high-temperature gas during combustion. The bottom is an ignition chamber 4.6, with an ignition hole 4.5 and a pressure measurement hole 4.7. A sealing disk 4.3 is provided on the outer peripheral surface of the lower part, and a sealing ring groove 4.4 is provided on the upper end surface of the sealing disk, which is used to form an end face seal with the inner disk surface of the bottom cover. The upper part of the combustion chamber is a cooling section 4.1. The gas channel 4.8 in the cooling section introduces the high-temperature gas generated in the combustion chamber into the upper valve seat chamber 4.9. The valve seat chamber 4.9 is provided with 8 evenly distributed air outlet holes 4.11 in the circumferential direction, and the total diameter area of ​​the air outlet holes 4.11 is more than 3 times that of the gas channel 4.8. The bottom of the valve seat chamber 4.9 is a valve face 4.12, and the circumferential surface is an internal thread, which is used to connect the ring frame of the self-unlocking component.

[0048] like Figure 7 As shown, the self-unlocking assembly 5 includes a pull rod 11, a hook 12, a ring frame 13, a valve core push rod 14, a limit ring 15, a hook shaft 16, and a sealing cover 17.

[0049] like Figure 8As shown, the pull rod 11 is a rotary rod structure, the upper part is a threaded section 11.1, the upper middle part is a positioning ring 11.2, the middle part is a pull rod body 11.3, the lower part is a lower end plate 11.4, and the periphery of the lower end plate 11.4 is a semicircular structure.

[0050] like Fig. 9 As shown, the hook 12 is a long strip structure, the upper part of which is a claw head 12.1, and the lower end surface of the claw head is a plane. The middle part of the hook is an inwardly inclined conical surface 12.2, the lower part is a retaining surface 12.3, and the lower rear part is a pin shaft hole 12.4.

[0051] like Fig.10 As shown, the ring frame 13 is a rotary sleeve structure, with a cross-shaped hook fixing groove 13.1 on the upper part, a threaded shaft hole 13.2 passing through the middle of the hook fixing groove 13.1, and a large-diameter through hole 13.3 on the outer side of the threaded shaft hole. The middle of the ring frame is a middle end plate 13.4, and the middle of the middle end plate is a head positioning through hole 13.5. The lower side of the ring frame is a valve core cavity 13.6, and the lower part of the valve core cavity is 8 circumferentially evenly distributed vents 13.7. The outer peripheral surface of the ring frame is a fine pitch thread 13.8, which is used to fix the ring frame in the valve seat cavity 4.9 of the gas generator.

[0052] like Fig.11 As shown, the valve core push rod 14 is a rotary stepped shaft structure. Its top is a ball head surface 14.1, and the middle and upper part is a straight column section 14.2, which is tangentially transitioned to the ball head surface. The middle of the valve core push rod 14 is a push rod 14.3, and the difference in radius between the push rod 14 and the straight column section 14.2 is consistent with the retraction stroke of the retaining surface 12.3 of the hook 12. The lower part of the valve core push rod is a valve core body 14.5, and the upper end surface of the valve core body is a position maintaining surface 14.4.

[0053] like Fig.12 As shown, the limit ring 15 is a thin-shell labyrinth-shaped rotating body or a concave hexagonal lattice. Its outer peripheral surface 15.1 is placed in the valve core cavity 13.6, and the inner peripheral surface 15.2 is sleeved on the outside of the push rod 14.3. The upper end surface 15.3 of the limit ring is tightly attached to the lower end surface of the middle end plate 13.4, and the lower end surface 15.4 is tightly attached to the position maintaining surface 14.4 of the valve core push rod. After being pressed, the height H becomes within 1 / 3 of the original.

[0054] The hook shaft 16 is a rotary rod structure with a threaded end and a smooth axis at the other end.

[0055] like Fig.13As shown, the sealing gland 17 is a rotating disc structure, and the upper part of the disc body 17.1 is a sealing cap 17.2. After tightening, it is ensured that no gas leaks directly from the threaded section 11.1. There is a threaded hole 17.3 in the middle of the disc body. After tightening with the threaded section 11.1 of the pull rod, the lower end face 17.4 is tightly attached to the upper end face of the diaphragm 3.3 of the inner shell. Two annular sealing ring grooves 17.5 are provided on the lower end face of the sealing gland. After the sealing rings contained therein are tightly attached to the diaphragm 3.3, a redundant sealing structure is formed to ensure that no gas leaks from the inner cavity of the device. The outer circumferential surface of the sealing gland 17 is provided with a plurality of tightening planes 17.6 for tightening.

[0056] When the self-unlocking assembly 5 is installed, the four hooks 12 are set in the hook fixing groove 13.1 of the ring frame. The hook shaft 16 is screwed into the large diameter through hole 13.3 of the ring frame, and passes through the threaded shaft hole 13.2 and the pin shaft hole 12.4 in turn, and is fixed after tightening. The claw heads 12.1 of the hooks uniformly distributed in the circumference hold and press the lower end plate 11.4 of the pull rod. At the same time, the lower end of the hook is limited by the straight column section 14.2 of the valve core push rod sandwiched between them and cannot be turned outward, that is, the pull rod 11 will not be released. The valve core push rod 14 is axially pressed against the valve face 4.12 of the gas generator by the limiting ring 15 and the ring frame 13. When the high-pressure gas is not introduced, no axial movement will occur, that is, the lock will not be misinterpreted, ensuring good environmental adaptability. After the threaded section 11.1 of the tie rod passes through the through hole 3.4 of the inner shell, the threaded hole 17.3 of the sealing gland 17 is screwed into the threaded section 11.1, pressing the diaphragm end face of the inner shell, tightening the tie rod 11 to form axial pre-tightening and forming a good seal.

[0057] like Fig.14 As shown, the working principle of the self-unlocking assembly is as follows: when the gas generator 4 is ignited, the high-pressure gas generated in the combustion chamber enters the lower part of the valve core push rod 14 along the gas channel 4.8, and then pushes the valve core push rod 14 to move upward and crushes the limit ring 15. Then the straight column section 14.2 of the valve core push rod is out of contact with the retaining surface 12.3 of the hook claw, and the ball head surface 14.1 pushes the inward-inclined cone surface 12.2 of the hook claw, pushing the hook claw 12 to turn outward, and the lower end plate of the pull rod 11 is unlocked. Then the high-pressure gas passes through the lower part of the opened valve core, enters the inner cavity of the inner shell 3 through the vent hole 13.7 and the outlet hole 4.11, and drives the drag reduction rod to unfold. The function of unlocking first and then unfolding is realized.

[0058] like Fig.15As shown, the anti-reverse rotation component 6 includes a clamping pin 21 and a square tongue 22. The clamping pin 21 is a rotary step shaft structure, with a threaded column 21.2 on the upper part, an elastic push rod 21.3 on the lower part, and a square wrench hole 21.1 on the top. The square tongue 22 has a positioning disk 22.1 on the upper part, a square columnar tongue body 22.2 on the lower part, and a wedge-shaped inclined surface 22.3 on the lower end face of the tongue body. During installation, the square tongue is placed in the square hole of the anti-reverse rotation component mounting hole on the upper end face of each shell, and then the clamping pin 21 is screwed into the M3 threaded hole until the elastic push rod clamps the positioning disk of the square tongue. During operation, when the cylindrical guide pin on the shell is screwed into the rotating U groove of the outer shell, the trajectory is shown by arrow 2.8. When the cylindrical guide pin enters the straight section, it will push the inclined surface 22.3 to move upward and compress the elastic push rod 21.3. When the cylindrical guide pin enters the straight section, the elastic push rod pushes the square tongue back to its original position, and the square tongue is inserted into the other side of the highest point of the cylindrical guide pin top, and cooperates with the reverse inclined surface 22.3 to effectively prevent the housing from returning due to vibration and other reasons, thereby achieving an anti-reverse rotation effect.

[0059] like Figure 1 As shown, the chassis 7 is a rotary ring structure. A threaded hole 7.1 is arranged in the middle, and an inverted ring 7.2 is connected to the middle of the chassis 7, and the top of the inverted ring 7.2 cooperates with the sealing ring groove 4.4. A sealing groove is provided on the outer circumferential surface of the chassis 7, and a sealing ring is arranged in the sealing groove to seal between the outer circumferential surface of the housing 1 and the outer circumferential surface of the chassis 7. A plurality of connecting holes are provided at the bottom of the outer circumferential surface of the housing 1, and connecting bolts pass through the connecting holes and are connected to the chassis 7, and the connecting bolts are located below the sealing ring.

[0060] like Figure 6 As shown, the threaded pressing ring 8 is a rotary annular structure. The outer peripheral surface is a threaded surface 8.1, the bottom is a bottom end surface 8.2, and the upper part is provided with a spacing groove 8.3, which is rotatably installed using a corresponding spacing tooth tooling. The top is a top end surface 8.4. The threaded hole 7.1 cooperates with the threaded surface of the outer peripheral surface of the threaded pressing ring 8.

[0061] The anti-loosening pressure ring 9 is a short rotary ring structure. The outer peripheral surface is a threaded surface 9.1, the bottom is a bottom end surface 9.2, and the upper part is provided with a spacing groove 9.3. The corresponding spacing tooth tooling is used for rotational installation, and the threaded hole 7.1 cooperates with the threaded surface of the outer peripheral surface of the anti-loosening pressure ring 9.

[0062] When installing the device, the gas generator 4 is passed through the threaded hole 7.1 of the chassis 7 until the upper end surface of the sealing disk 4.3 is tightly attached to the lower end surface of the inner ring 7.2. At this time, the threaded section 11.1 of the tie rod in the self-unlocking component 5 on the upper part of the gas generator passes through the through hole 3.4 of the inner shell, and then the sealing gland 17 is tightened from the top. Then the threaded pressing ring 8 is screwed into the threaded hole 7.1 of the chassis to press the sealing disk 4.3 of the gas generator. Then the anti-loosening pressing ring 9 is screwed into the threaded hole 7.1 of the chassis until its bottom end surface 9.2 presses the top end surface 8.4 of the threaded pressing ring to form a double nut anti-loosening structure.

[0063] The overall working principle is that after the gas generator drives the self-unlocking component to unlock, high-pressure gas enters the inner cavity of the drag reduction rod to push each part to unfold. During the unfolding process, a circumferential closed cavity is formed between the two adjacent shells, and the exhaust can only be slowly exhausted through the throttling vent holes of each shell section. When the inner shell is about to unfold in place, the pressure of the outer closed cavity is already high, which can form a gas blocking effect and achieve deceleration and buffering for the high-speed moving inner shell. And during the exhaust, the inner shell is prevented from rebounding. At the end of the movement of the slow inner shell, its cylindrical guide pin enters the rotating U groove of the outer shell and rotates to the horizontal segment locking position. The unfolding work is completed.

[0064] A performance test method for a self-unlocking and self-buffering rotary locking multi-section drag reduction rod. Since the performance of the drag reduction rod includes unlocking performance, deployment performance, sealing performance and modal damping, the performance is measured through an inflation deployment test and a non-contact modal test.

[0065] like Fig.16 As shown, the inflation deployment test method is as follows: the outer shell 1 of the drag reduction rod is fixed on the test bracket. The inflation tooling with the same structure as the gas generator 4 and the self-unlocking component 5 is installed in the middle of the chassis 7. No gunpowder is installed inside the inflation tooling. The inflation tooling is connected to the gas source through an inflation passage. The inflation passage is connected with a switch F1 and a pressure measuring device in sequence along the airflow charging direction. The inflation passage is connected with a deflation passage between the switch F1 and the pressure measuring device, and the deflation passage is connected with a switch F2. The internal pressure of the drag reduction rod is measured by the pressure measuring device. In this embodiment, the pressure measuring device is a pressure gauge. It should be ensured that there is no leakage in the inflation pipeline during the test. Compressed air / nitrogen is filled into the drag reduction rod. When the drag reduction rod begins to unlock, the pressure inside the drag reduction rod is recorded. After the drag reduction rod begins to unfold, the compressed air / nitrogen is slowly filled without decompression until the drag reduction rod is unfolded in place (unfolding stroke 1.8m), and the pressure change process during the unfolding process and the pressure value inside the drag reduction rod when it is unfolded in place are recorded. Continue to fill the device with compressed air / nitrogen until the pressure inside the drag reduction device reaches 0.45MPa (gauge pressure), close the inflation and deflation passages, and conduct an airtightness inspection test on the drag reduction device. The test time is 3 minutes, and the pressure change process inside the drag reduction device is continuously recorded.

[0066] like Fig.17 As shown, the non-contact modal test method is: the drag reduction device in the deployed state is installed on a special fixture, and the rod is inflated through the inflation fixture, and then the vibration displacement process of the characteristic position of the drag reduction rod is measured using a laser micrometer.

[0067] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0068] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod, characterized in that: The invention comprises an outer shell (1), an intermediate shell group (2), an inner shell (3), a gas generator (4), a self-unlocking component (5), an anti-reverse rotation component (6), a chassis (7), a threaded pressure ring (8) and an anti-loosening pressure ring (9), wherein the intermediate shell group (2) is located in the outer shell (1), the inner shell (3) is located in the intermediate shell group (2), and the intermediate shell group (2) comprises a plurality of shells which are sleeved in sequence; Among the outer shell (1), the shell and the inner shell (3), any two adjacent ones form an outer shell and an inner shell, the inner wall top of the outer shell is provided with a raised inner ring segment, the inner ring segment is provided with a plurality of rotating U-grooves along the circumference, the rotating U-groove comprises a semicircular segment and a horizontal vertical segment, the semicircular segment is an arc-shaped groove with a central angle of 90 degrees, one end of the semicircular segment penetrates to the bottom edge of the inner ring segment and is perpendicular to the bottom edge of the inner ring segment, the other end of the semicircular segment is connected to the horizontal vertical segment, and the horizontal vertical segment extends along the circumference of the inner ring segment; the outer wall surface of the inner shell is provided with a cylindrical guide pin, the cylindrical guide pin is matched with the rotating U-groove one by one, the bottom of the outer wall surface of the inner shell is provided with a raised outer ring segment, the outer ring segment is provided with an axially distributed sealing ring groove, and the sealing ring groove is used to place an O-ring; The chassis (7) is fixedly connected to the bottom of the outer shell (1), the shell and the inner shell (3) are located above the chassis (7), the gas generator (4) is fixedly connected to the middle of the chassis (7) and extends into the inner shell (3), is compressed by a threaded pressure ring (8), and is locked and prevented from loosening by an anti-loosening pressure ring (9); the self-unlocking component (5) is arranged at the outlet position of the gas generator (4), so that the outlet of the gas generator (4) is opened after the self-unlocking component (5) is unlocked; the anti-reverse rotation component (6) is installed on the inner circle section and is located at the intersection of the semicircular section and the horizontal and vertical section, so that the cylindrical guide pin is locked in the horizontal and vertical section after the cylindrical guide pin enters the horizontal and vertical section.

2. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 1, characterized in that: A plurality of air-guiding U-grooves are provided at the bottom of the inner wall surface of the inner ring section, and throttling air leakage holes are provided at the upper parts of the air-guiding U-grooves, and the throttling air leakage holes are connected to the inner and outer sides of the external shell.

3. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 1, characterized in that: The inner ring section is provided with an anti-reverse rotation component mounting hole, the anti-reverse rotation component mounting hole comprises an upper threaded hole and a lower square hole, the anti-reverse rotation component (6) comprises a clamping pin (21) and a square tongue (22), the clamping pin (21) is a rotary step shaft structure, the upper part of which is a threaded column (21.2), and the lower part is an elastic push rod (21.3), the upper part of the square tongue (22) is a positioning disk (22.1), and the lower part is a square columnar tongue body (22.2), the lower end face of the tongue body is a wedge-shaped inclined surface (22.3), along the circumferential direction of the inner ring section, the end of the inclined surface (22.3) close to the semicircular section is lower than the end close to the horizontal section, the tongue body (22.2) passes through the square hole, the positioning disk (22.1) is located above the square hole, the threaded column (21.2) is threadedly connected in the threaded hole, and the elastic push rod (21.3) is in contact with the positioning disk (22.1).

4. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 1, characterized in that: One end of the semicircular segment that passes through the bottom edge of the inner ring segment is the entrance end, and rounded corners are arranged on both sides of the entrance end.

5. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 1, characterized in that: The gas generator (4) is provided with an ignition chamber (4.6), a combustion chamber (4.2), a gas channel (4.8) and a valve seat chamber (4.9) in sequence from the bottom to the top. The combustion chamber (4.2) contains a gunpowder block, which generates a large amount of high-temperature gas when burning. The ignition chamber (4.6) is used to install an ignition device to ignite the gunpowder block. The valve seat chamber (4.9) extends to the top of the gas generator (4). The valve seat chamber (4.9) is provided with a plurality of evenly distributed gas outlet holes (4.11) in the circumferential direction. The axes of the gas outlet holes (4.11) are along the radial direction of the gas generator (4) and extend to the outer wall of the gas generator (4). The self-unlocking component (5) is installed in the valve seat chamber (4.9). The high-temperature gas generated by the combustion of the gunpowder block enters the self-unlocking component (5) in the valve seat chamber (4.9) through the gas channel (4.8). When the self-unlocking component (5) is opened, the gas outlet holes (4.11) are opened.

6. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 5, characterized in that: The total diameter area of ​​the gas outlet holes (4.11) is more than three times the cross-sectional area of ​​the gas channel (4.8).

7. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 5, characterized in that: The self-unlocking component (5) comprises a pull rod (11), a hook (12), a ring frame (13), a valve core push rod (14), a hook shaft (16) and a sealing cover (17); a transverse partition (3.3) is provided in the inner shell (3); the gas generator (4) is located on the side of the transverse partition (3.3) facing the bottom plate (7); one end of the pull rod (11) is connected to the transverse partition (3.3); the other end of the pull rod (11) is a lower end plate (11.4); the lower end plate (11.4) is used to connect the hook (12); the ring frame (13) is threadedly connected to the circumferential surface of the inner wall of the valve seat cavity (4.9); the ring frame (13) is provided with a plurality of vent holes which are directly opposite to the air outlet holes (4.11) (13.7), the upper part of the ring frame (13) is a cross-shaped hook fixing groove (13.1), the ring frame (13) is provided with a middle end plate (13.4) and a valve core cavity (13.6) in sequence below the hook fixing groove (13.1), the middle end plate (13.4) is provided with a head positioning through hole (13.5) at the axial position, and the head positioning through hole (13.5) connects the hook fixing groove (13.1) with the valve core cavity (13.6); the valve core push rod (14) comprises a straight column section (14.2), a push rod (14.3) and a valve core body (14.5) connected in sequence, and the end of the straight column section (14.2) away from the push rod (14.3) is a ball head surface (14.1), A concave groove is provided at one end of the valve core body (14.5) away from the push rod (14.3), the valve core body (14.5) is located in the valve core cavity (13.6), the top end of the straight column section (14.2) passes through the top head positioning through hole (13.5) and extends into the center position of the hook claw fixing groove (13.1), and the limit ring (15) is arranged between the valve core body (14.5) and the middle end plate (13.4); one end of the hook claw (12) is located in the hook claw fixing groove (13.1) and is rotatably connected to the ring frame (13) so that the top of the hook claw (12) can approach or move away from the axis of the valve core push rod (14), and the hook claw (12) is arranged in sequence from bottom to top on the side facing the axis of the valve core push rod (14). The retaining surface (12.3), the inwardly inclined conical surface (12.2) and the claw head (12.1), when the retaining surface (12.3) and the straight column section (14.2) are fitted together, the claw head (12.1) is hooked on the upper surface of the lower end plate (11.4); along the direction away from the retaining surface (12.3), the inwardly inclined conical surface (12.2) gradually approaches the axis direction of the valve core push rod (14) relative to the plane where the retaining surface (12.3) is located; as the valve core push rod (14) moves upward, the ball head surface (14.1) contacts the inwardly inclined conical surface (12.2) and gradually pushes the hook claw (12) to rotate, so that the top of the hook claw (12) can move away from the axis direction of the valve core push rod (14).

8. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 7, characterized in that: The pull rod (11) comprises a threaded section (11.1), a positioning ring (11.2), a pull rod body (11.3) and a lower end plate (11.4) which are arranged in sequence in the axial direction of the salt itself; the positioning ring (11.2) is located on the side of the transverse partition (3.3) facing the bottom plate (7); and the end of the threaded section (11.1) passing through the transverse partition (3.3) is threadedly connected to a sealing gland (17).

9. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 8, characterized in that: When the self-unlocking assembly (5) is installed, the hook (12) is installed in the hook fixing groove (13.1) of the ring frame, the limit ring (15) and the valve core push rod (14) are installed in the valve core cavity (13.6), and the claw head (12.1) is made to hold and press the lower end plate (11.4), the ring frame (13) equipped with the limit ring (15) and the valve core push rod (14) is installed in the valve seat cavity (4.9), the gas generator (4) is installed on the chassis (7), and the threaded section (11.1) of the pull rod is passed through the cross partition (3.3), and the sealing cover (17) is connected to the threaded section (11.1), so that the pull rod (11) is tightened to form axial preload.

10. The self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to claim 1, characterized in that: The chassis (7) is a rotary ring structure, the middle of which is a cylindrical structure, the inner wall surface of the cylindrical structure is provided with a threaded hole (7.1), the top of the cylindrical structure is an inverted ring (7.2), the outer peripheral surface of the gas generator (4) is provided with a sealing disk (4.3), the upper end surface of the sealing disk is provided with a sealing ring groove (4.4), the inverted ring (7.2) is clamped in the sealing ring groove (4.4), and the cylindrical structure is threadedly connected to an anti-loosening pressure ring (9) and a threaded pressure ring (8) in sequence through a threaded hole (7.1) on the side of the sealing disk (4.3) away from the inverted ring (7.2); The threaded pressure ring (8) is an annular rotating body structure, with a pressure plane (8.2) at the front end, a spacing groove (8.3) at the rear end, and an external thread (8.1) on the outer peripheral surface. When installing, a tightening tool (10) is used, wherein the intermediate hole (10.2) passes through the lower cylindrical section (4.13) of the gas generator (4), and the front end teeth (10.1) are inserted into the spacing groove (8.3), and then a sleeve is used to insert the square section (4.14) of the gas generator (4) to prevent When the threaded pressing ring (8) is tightened, the gas generator (4) is driven to rotate; the wrench clamps the outer eight sides (10.3), and the threaded pressing ring (8) is tightened by tightening the tool (10), so that the pressing plane (8.2) is pressed against the rear end surface of the sealing disk (4.3); the locking pressing ring (9) has the same structure as the threaded pressing ring (8), but is smaller in height; after tightening, the pressing plane (9.2) of the locking pressing ring (9) presses against the rear end surface (8.3), forming a double nut anti-loosening structure.

11. A performance test method for a self-unlocking, self-buffering, rotating and locking multi-section drag reduction rod according to any one of claims 1 to 10, characterized in that: Including inflation and deployment tests and non-contact modal tests, The inflation deployment test comprises: the drag reduction rod is fixed on the test bracket through the shell (1); an inflation tool is installed in the middle of the chassis (7) of the drag reduction rod; the structure of the inflation tool is consistent with the gas generator (4) and the self-unlocking component (5); no gunpowder is installed inside the inflation tool; the inflation tool is connected to the gas source through an inflation passage; a switch F1 and a pressure measuring device are connected to the inflation passage in sequence along the direction of air flow filling; an air release passage is connected between the switch F1 and the pressure measuring device; the air release passage is connected to a switch F2; compressed air is filled into the drag reduction rod; When the drag reduction rod begins to unlock, the pressure inside the drag reduction rod is recorded by the pressure measuring device. After the drag reduction rod begins to unfold, the pressure is not relieved but the compressed air or nitrogen is slowly filled in until the drag reduction rod is fully unfolded. The pressure change process during the unfolding process and the pressure value inside the drag reduction rod when fully unfolded are recorded. The compressed air or nitrogen is continuously filled in until the pressure inside the drag reduction device reaches the set pressure. The inflation passage and the deflation passage are closed, and the drag reduction device is subjected to an airtightness inspection test. During the test time of the airtightness inspection test, the pressure change process inside the drag reduction device is continuously recorded. The non-contact modal test comprises: the drag reduction rod in the unfolded state is fixed on the test bracket through the shell (1), the rod is inflated by the inflation tool, the frequency is firstly swept by the excitation device according to the random vibration process, and the vibration displacement process of the characteristic position of the drag reduction rod is measured by the laser micrometer, and the first-order frequency value f1 is determined according to the first frequency value of the drag reduction rod generating resonance, and then the excitation device is used to excite on both sides of the narrow band f1 frequency in a sinusoidal vibration mode, and the vibration displacement process of the characteristic position of the drag reduction rod is measured by the laser micrometer to determine the accurate value of f1.

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