A pyrotechnic rotary drive device

Abstract

The application discloses a pyrotechnic rotary drive device for outputting torque, which comprises a hollow shell structure, an igniter arranged at one end of the hollow shell structure and used for outputting axial power to the inner cavity of the hollow shell structure, a spiral motion structure located in the inner cavity of the hollow shell structure and used for moving along a spiral track under the action of the power output by the igniter, and a torque transmission structure arranged on the hollow shell structure, wherein the torque transmission structure and the hollow shell structure can relatively rotate but limit the freedom degree of relative axial sliding, a part of the torque transmission structure is connected with the spiral motion structure, the torque transmission structure and the spiral motion structure can relatively axially slide but limit the freedom degree of relative rotation, so that the torque transmission structure rotates under the driving of the spiral motion structure, and the other part of the torque transmission structure is located outside the hollow shell structure to output torque. The pyrotechnic rotary drive device can fully exert the advantages of small volume and strong driving capacity of a pyrotechnic drive device.

Description

Technical Field

[0001] This application relates to the technical field of output torque pyrotechnic actuators, and more particularly to a pyrotechnic rotary drive device based on a multi-start sliding screw. Background Technology

[0002] With technological advancements and the increasing demand for stealth aircraft, the need for folding and deploying control wings is growing. However, as aircraft speeds increase, traditional electrical or reed-driven systems are becoming increasingly inadequate for mission requirements. Pyrotechnic devices, which utilize the combustion of gunpowder to generate gas and perform work, are small in size but high in energy, leading to the increasing use of pyrotechnic drive systems in folding and deploying control wing configurations.

[0003] Currently, most aircraft use pyrotechnic linear actuators to drive external connecting rods or helical pairs to deploy folding control wings. However, with the miniaturization of aircraft, the low space utilization of these combined drive systems has become increasingly apparent. Even with pyrotechnic linear actuators and helical pairs, the axial dimensions are still too large. Therefore, in recent years, pyrotechnic rotary actuators that directly output torque have emerged in the industry. However, current pyrotechnic rotary actuators generally use ball screws. Under the enormous thrust generated by high-pressure gas, the rolling contact of the linear contact leads to excessive contact stress, and the transmission pair is prone to plastic deformation, resulting in jamming. Furthermore, due to structural limitations, existing pyrotechnic rotary actuators cannot incorporate a ball recirculation structure, and the helical pair cannot achieve pure rolling during actual operation, still exhibiting sliding friction from line contact.

[0004] In summary, existing pyrotechnic rotary actuators cannot fully utilize the advantages of small size and high energy of pyrotechnic products, and insufficient output torque limits their application. Summary of the Invention

[0005] This application provides a pyrotechnic rotary drive device with output torque. This pyrotechnic rotary drive device is a small-sized pyrotechnic rotary actuator with a large output torque. This device fully utilizes the advantages of small size and strong driving capability of pyrotechnic actuators, and its helical transmission pair is no longer a weak point that limits its output torque.

[0006] In a first aspect, a pyrotechnic rotary drive device for outputting torque is provided, comprising:

[0007] Hollow shell structure;

[0008] An igniter, located at one end of the hollow shell structure, is used to output axial power into the inner cavity of the hollow shell structure.

[0009] The spiral motion structure is located in the inner cavity of the hollow shell structure. It is used to move along a spiral trajectory under the power output of the igniter, so that the spiral motion structure itself has rotational motion and axial sliding.

[0010] A torque transmission structure is installed on a hollow shell structure. The torque transmission structure and the hollow shell structure can rotate relative to each other, but the degree of freedom of relative axial sliding is restricted. A part of the torque transmission structure is connected to a helical motion structure. The torque transmission structure and the helical motion structure can slide relative to each other axially, but the degree of freedom of relative rotation is restricted. Thus, the torque transmission structure rotates under the drive of the helical motion structure. The other part of the torque transmission structure is located outside the hollow shell structure to output torque.

[0011] In conjunction with the first aspect, in the first implementation of the first aspect, the helical motion structure has a motion cavity, the torque transmission structure is rod-shaped, and the part of the torque transmission structure connected to the helical motion structure extends into the motion cavity, which is used to provide axial relative sliding stroke space for the torque transmission structure.

[0012] In conjunction with the first implementation of the first aspect, in the second implementation of the first aspect, the helical motion structure includes:

[0013] The piston is used to bear the thrust from the igniter;

[0014] The multi-start screw comprises a first part, a second part, and a third part. The first part of the multi-start screw is fixed to the piston, so that the multi-start screw can move along a helical trajectory relative to the hollow shell structure under the drive of the piston. The second part of the multi-start screw is located between the first part and the third part. The second part of the multi-start screw has a cavity for providing axial relative sliding stroke space for the torque transmission structure. The third part of the multi-start screw is used to cooperate with the torque transmission structure to restrict the degree of freedom of relative rotation between the torque transmission structure and the helical motion structure.

[0015] In conjunction with the second implementation of the first aspect, in the third implementation of the first aspect, the piston is a structural component that is closed at one end and open at the other end. The piston is positioned facing the igniter at the closed end, and the high-pressure medium output by the igniter acts on the end face of the closed end of the piston.

[0016] The multi-start screw has a screw cavity that connects the first part and the second part of the multi-start screw. The open end of the piston is threadedly fixed to the open end of the screw cavity. At the end of the axial sliding stroke of the multi-start screw, the torque transmission structure gradually penetrates into the opening of the piston.

[0017] In combination with the second or third implementation of the first aspect, in the fourth implementation of the first aspect, the third part of the multi-start screw has a screw through hole, which is connected to the bottom of the cavity of the second part of the multi-start screw. The torque transmission structure passes through the screw through hole, which has a keyway. The torque transmission structure has a key bar, and the keyway and key bar cooperate to restrict the degree of freedom of relative rotation between the torque transmission structure and the helical motion structure.

[0018] In combination with the second to fourth implementations of the first aspect, in the fifth implementation of the first aspect, the piston is used for a dynamic sealing connection with the inner cavity wall of the hollow shell structure, and the outer periphery of the multi-start screw has threads; the inner cavity wall of the hollow shell structure has a threaded track that matches the threads of the helical motion structure, so that the helical motion structure can move relative to the hollow shell structure along a helical trajectory.

[0019] Secondly, a pyrotechnic rotary drive device with output torque is provided, comprising:

[0020] Hollow shell structure;

[0021] An igniter, located at one end of the hollow shell structure, is used to output axial power into the inner cavity of the hollow shell structure.

[0022] The spiral motion structure is located inside the hollow shell structure and is used to move along a spiral trajectory under the power output of the igniter.

[0023] A torque transmission structure is installed on a hollow shell structure. The torque transmission structure and the hollow shell structure can rotate relative to each other, but the degree of freedom of relative axial sliding is restricted. A part of the torque transmission structure is connected to a helical motion structure. The torque transmission structure and the helical motion structure can slide relative to each other axially, but the degree of freedom of relative rotation is restricted. Thus, the torque transmission structure rotates under the drive of the helical motion structure. The other part of the torque transmission structure is located outside the hollow shell structure to output torque.

[0024] In conjunction with the second aspect, in the first implementation of the second aspect, the helical motion structure includes:

[0025] The piston is dynamically sealed to the inner cavity wall of the hollow shell structure; the first side of the piston is used to carry the high-pressure medium output by the igniter to push the piston away from the igniter.

[0026] The multi-start lead screw is fixedly connected to the second side of the piston. Under the drive of the piston, the multi-start lead screw can move along a helical trajectory relative to the hollow shell structure. The multi-start lead screw has a lead screw cavity and a lead screw through hole. The lead screw through hole is connected to the bottom of the lead screw cavity. The torque transmission structure passes through the lead screw through hole. During the movement of the multi-start lead screw, the torque transmission structure gradually penetrates into the lead screw cavity.

[0027] In conjunction with the first implementation of the second aspect, in the second implementation of the second aspect, the piston is a structural component with one end closed and the other end open. The piston is positioned facing the igniter at the end face of the closed end. The high-pressure medium output by the igniter acts on the end face of the closed end of the piston. The open end of the piston is fixedly connected to the open thread of the lead screw cavity. At the end of the axial sliding stroke of the multi-start lead screw, the torque transmission structure gradually penetrates into the opening of the piston.

[0028] In combination with the first aspect, any one of the first to fifth implementations of the first aspect, in the sixth implementation of the first aspect, or in combination with some implementations of the second aspect, the outer periphery of the helical motion structure has threads; the inner cavity wall of the hollow shell structure has a threaded track that matches the threads of the helical motion structure, so that the helical motion structure can move relative to the hollow shell structure along a helical trajectory.

[0029] In conjunction with the sixth implementation of the first aspect, in the seventh implementation of the first aspect, or in conjunction with some implementations of the second aspect, the hollow shell structure includes:

[0030] The housing has an actuating cavity;

[0031] The lead screw nut has its outer periphery engaged with the actuating cavity wall of the housing, restricting the relative rotation and relative axial sliding degrees of freedom between the lead screw nut and the housing. The inner wall of the lead screw nut is engaged with the outer thread of the helical motion structure, so that the helical motion structure can move relative to the lead screw nut along a helical trajectory within the actuating cavity.

[0032] In combination with the seventh implementation of the first aspect, in the eighth implementation of the first aspect, or in combination with some implementations of the second aspect, the relative rotational degrees of freedom between the lead screw nut and the housing are restricted by splines;

[0033] The actuating chamber wall of the housing is provided with a step, and the side of the lead screw nut away from the igniter abuts against the step to limit the degree of freedom of the lead screw nut to move axially away from the igniter.

[0034] The hollow shell structure also includes a charge body, which is located on the side of the shell near the igniter. The charge body has a power chamber, the opening of which extends into the actuation chamber of the shell and is threadedly fixed. The actuation chamber of the shell and the power chamber of the charge body are connected to form the inner cavity of the hollow shell structure. The end face of the charge body near the shell abuts against the lead screw nut to restrict the degree of freedom of the lead screw nut to move axially toward the igniter.

[0035] In conjunction with the eighth implementation of the first aspect, in the ninth implementation of the first aspect, or in conjunction with some implementations of the second aspect, the charge body further has two exhaust ports communicating with the power chamber, an igniter is sealed and installed at one end of the charge body, and the output end of the igniter is connected to the two exhaust ports of the charge body to output a high-pressure medium into the inner cavity of the hollow shell structure.

[0036] Thirdly, a pyrotechnic rotary drive device based on a multi-start sliding screw is provided, comprising:

[0037] The propellant charge body has a power chamber and two exhaust ports connected to the power chamber;

[0038] The igniter is sealed at one end of the charge body, and the output end of the igniter is connected to the two exhaust holes of the charge body to output high-pressure medium to the power chamber.

[0039] The shell has an actuation cavity, the opening of which is threadedly fixedly connected to the opening of the power cavity of the charge body, and the actuation cavity of the shell is connected to the power cavity of the charge body.

[0040] In its initial state, the piston is dynamically sealed and installed in the power chamber of the charge body. The piston is a structural component that is closed at one end and open at the other end. The piston is positioned with the end face of the closed end facing the igniter. The high-pressure medium output by the igniter acts on the end face of the closed end of the piston to push the piston toward the housing.

[0041] A multi-start lead screw is housed within the actuating cavity of a housing. The multi-start lead screw has a lead screw cavity and a lead screw through hole. The opening of the lead screw cavity and the opening of the piston are threadedly fixedly connected. The lead screw through hole communicates with the bottom of the lead screw cavity. The multi-start lead screw can move relative to the housing along a helical trajectory.

[0042] The torque transmission structure has its middle section passing through the bottom of the housing's actuation cavity. One end of the torque transmission structure, near the igniter, extends into the screw cavity through the screw through-hole of the multi-start screw. A structure for transmitting torque is provided at the end of the torque transmission structure opposite to the igniter. The torque transmission structure and the housing can rotate relative to each other, but the degree of freedom for axial sliding between them is restricted. The multi-start screw and the torque transmission structure can slide axially, but the degree of freedom for relative rotation between them is restricted.

[0043] During operation, under the thrust of the igniter, the piston and the multi-start screw move away from the igniter axis. The multi-start screw gradually penetrates into the actuation cavity of the housing and rotates along the spiral trajectory. The torque transmission structure rotates relative to the housing under the drive of the multi-start screw, and at the same time, the torque transmission structure gradually penetrates into the space connecting the piston cavity and the screw cavity.

[0044] In conjunction with the third aspect, in the first implementation of the third aspect, the housing is further provided with a lead screw nut in the actuation cavity; the outer periphery of the lead screw nut cooperates with the cavity wall of the actuation cavity of the housing and restricts the relative rotation and relative axial sliding degrees of freedom of the lead screw nut and the housing, and the inner wall of the lead screw nut cooperates with the outer peripheral thread of the helical motion structure, so that the helical motion structure can move along the helical trajectory relative to the lead screw nut in the actuation cavity.

[0045] In conjunction with the first implementation of the third aspect, in the second implementation of the third aspect, the actuation cavity wall of the housing is provided with a step, and the side of the lead screw nut away from the igniter abuts against the step to limit the degree of freedom of the lead screw nut to move axially away from the igniter.

[0046] The end face of the propellant charge near the housing abuts against the lead screw nut to restrict the degree of freedom of the lead screw nut to move axially toward the igniter.

[0047] In the third implementation of the third aspect, which combines the first or second implementation of the third aspect, the relative rotational degrees of freedom between the lead screw nut and the housing are restricted by splines.

[0048] In combination with any of the first to third implementations of the third aspect, in the fourth implementation of the third aspect, the number of threads of the screw nut that mates with the helical motion structure is 10 to 20, the helix angle is not less than 50°, and the tooth profile is a 30° standard trapezoidal thread or a rectangular thread.

[0049] In conjunction with the eighth or ninth implementation of the first aspect, in the tenth implementation of the first aspect, or in conjunction with some implementations of the second or third aspect, the cooperation between the charge body and the piston satisfies at least one of the following:

[0050] The inner wall of the charge body has steps to limit the axial position of the piston in the initial state;

[0051] When the piston is at its maximum axial sliding stroke, the piston still engages with the inner wall of the charge body through the O-ring seal.

[0052] In conjunction with the first aspect, any one of the first to tenth implementations of the first aspect, in the eleventh implementation of the first aspect, or in conjunction with some implementations of the second and third aspects, the hollow shell structure has a limiting through hole at the end away from the igniter. The limiting through hole communicates with the bottom of the inner cavity of the hollow shell structure and passes through the torque transmission structure. The torque transmission structure has an annular boss, which is housed in the inner cavity of the hollow shell structure. The outer diameter of the annular boss is larger than the inner diameter of the limiting through hole. The annular boss of the torque transmission structure abuts against the bottom of the inner cavity of the hollow shell structure, thereby restricting the degree of freedom of the torque transmission structure to move axially toward the igniter.

[0053] On the side of the limiting through hole of the hollow shell structure away from the annular boss, the torque transmission structure has an annular groove for installing a shaft elastic retaining ring. The outer diameter of the elastic retaining ring is larger than the inner diameter of the limiting through hole, thereby restricting the degree of freedom of the torque transmission structure to move away from the igniter axially through the shaft elastic retaining ring.

[0054] In combination with the first aspect, any one of the first to eleventh implementations of the first aspect, in the twelfth implementation of the first aspect, or in combination with some implementations of the second and third aspects, the pyrotechnic rotary drive device further includes a positioning pin, which passes laterally through the hollow shell structure and is inserted into the torque transmission structure to achieve initial fixation.

[0055] Fourthly, an aircraft is provided, including a pyrotechnic rotary drive as described in any of the implementations of the first to third aspects above.

[0056] Compared with the prior art, the solution provided in this application has at least the following beneficial technical effects:

[0057] (1) The present invention directly outputs torque, which, compared with the traditional method of converting torque into torque through an external helical pair in pyrotechnic linear drive, reduces the axial dimension by at least 50%, resulting in a smaller volume and lighter weight.

[0058] (2) The present invention uses a multi-start sliding helical screw and a multi-start sliding spline to realize helical transmission. Compared with the point / line contact of the ball screw pair, the helical pair of the present invention is a surface contact, with a large contact area and small contact stress under the same torque, so the ultimate output torque is greater.

[0059] (3) The igniter of the present invention is arranged axially, which, compared with the lateral arrangement of the igniter, makes it easier for the product to be embedded in the rudder shaft, and is more conducive to the overall structural arrangement. Attached Figure Description

[0060] Figure 1 A schematic diagram of a pyrotechnic rotary drive device for outputting torque is provided by the present invention.

[0061] Figure 2 A schematic diagram of another pyrotechnic rotary drive device for output torque provided by the present invention.

[0062] Figure 3 This is a schematic diagram of a spiral motion structure provided by the present invention.

[0063] Figure 4 This is a schematic diagram of a hollow shell structure provided by the present invention.

[0064] Figure 5 This is a simplified structural diagram of Embodiment 1 of the present invention (in a non-working state).

[0065] Figure 6 This is a schematic diagram of the shell structure in Embodiment 1 of the present invention.

[0066] Figure 7 This is a schematic diagram of the torque transmission structure in Embodiment 1 of the present invention.

[0067] Figure 8 This is a schematic diagram of the structure of the multi-start lead screw in Embodiment 1 of the present invention.

[0068] Figure 9 This is a schematic diagram of the lead screw nut in Embodiment 1 of the present invention.

[0069] Figure 10 This is a schematic diagram of the structure after operation in Embodiment 1 of the present invention. Detailed Implementation

[0070] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0071] like Figure 1 and Figure 2 As shown, the present invention discloses a pyrotechnic rotary drive device for outputting torque, comprising: a hollow shell structure A, an igniter 1, a helical motion structure B, and a torque transmission structure 7. The igniter 1 is disposed at one end of the hollow shell structure A and is used to output axial power to the inner cavity of the hollow shell structure A. The helical motion structure B is located in the inner cavity of the hollow shell structure A and is used to move along a helical trajectory under the power output by the igniter 1. The torque transmission structure 7 is disposed on the hollow shell structure A. The torque transmission structure 7 and the hollow shell structure A can rotate relative to each other, but their relative axial sliding freedom is restricted. A portion of the torque transmission structure 7 is connected to the helical motion structure B, and the torque transmission structure 7 and the helical motion structure B can slide relative to each other axially, but their relative rotational freedom is restricted. Thus, the torque transmission structure 7 rotates under the drive of the helical motion structure B. The other portion of the torque transmission structure 7 is located outside the hollow shell structure A to output torque.

[0072] Because the torque transmission structure 7 and the helical motion structure B can slide relative to each other axially, one of the torque transmission structure 7 and the helical motion structure B can provide axial sliding stroke space to the other. Figure 1 In the illustrated embodiment, the helical motion structure B has a motion cavity, and the torque transmission structure 7 is rod-shaped. The portion of the torque transmission structure 7 connected to the helical motion structure B extends into the motion cavity, which provides axial relative sliding travel space for the torque transmission structure 7. Figure 2In the embodiment shown, the torque transmission structure 7 has a motion cavity, and the end of the helical motion structure B near the torque transmission structure 7 is rod-shaped. The portion of the helical motion structure B that is connected to the torque transmission structure 7 extends into the motion cavity, which provides axial relative sliding stroke space for the torque transmission structure 7.

[0073] and Figure 2 Compared to the embodiments shown, Figure 1 The outer periphery of the helical motion structure B can have a relatively long mating length with the inner wall of the hollow shell structure A. Therefore, various mating relationships can be formed between the outer periphery of the helical motion structure B and the inner wall of the hollow shell structure A to fully improve the overall performance of the pyrotechnic rotary drive device. For example, a sealing ring can be provided on the outer periphery of the helical motion structure B near the igniter 1. As the helical motion structure B moves, the sealing ring on the helical motion structure B can always form a dynamic seal with the inner wall of the hollow shell structure A. In addition, the outer periphery of the helical motion structure B that does not participate in the dynamic seal can be provided with threads, and a track can be provided on the inner wall of the hollow shell structure A to constrain the helical motion of the helical motion structure B. The two cooperate with each other so that the helical motion structure B can move along a helical trajectory relative to the hollow shell structure A. Furthermore, this track can be located outside the total stroke of the sealing ring on the helical motion structure B, that is, the two will not interfere with each other.

[0074] Combination Figure 1 In some embodiments, such as Figure 3 As shown, the helical motion structure B can achieve dynamic sealing and helical motion trajectory through two structural components. The helical motion structure B can include a piston 4 and a multi-start screw 5. The piston 4 is used to achieve dynamic sealing (e.g., through an O-ring seal 3) and can also bear the thrust from the igniter 1. The multi-start screw 5 is used to achieve the helical motion trajectory and cooperates with the torque transmission structure 7 to drive the torque transmission structure 7 to rotate together.

[0075] like Figure 3 As shown, the multi-start screw 5 can be divided into a first part, a second part, and a third part. The first part of the multi-start screw 5 is fixed to the piston 4, so that the multi-start screw 5 can move along a helical trajectory relative to the hollow shell structure A under the drive of the piston 4. The second part of the multi-start screw 5 is located between the first part and the third part. The second part of the multi-start screw 5 has a cavity for providing axial relative sliding stroke space for the torque transmission structure 7. The third part of the multi-start screw 5 is used to cooperate with the torque transmission structure 7 to restrict the degree of freedom of relative rotation between the torque transmission structure 7 and the helical motion structure B.

[0076] To avoid increasing the axial length of the multi-start lead screw 5, the axial relative sliding stroke space of the torque transmission structure 7 can also be provided by the piston 4. For example... Figure 3 As shown, piston 4 is a structure with one end closed and the other end open. The piston 4 is positioned facing the igniter 1 at the closed end. The high-pressure medium output by the igniter 1 acts on the closed end face of piston 4. The multi-start screw 5 has a screw cavity that connects the first part and the second part of the multi-start screw 5. The open end of piston 4 is threadedly fixed to the open end of the screw cavity. At the end of the axial sliding stroke of multi-start screw 5, torque transmission structure 7 gradually penetrates into the opening of piston 4.

[0077] In some embodiments, the third part of the multi-start screw 5 and the torque transmission structure 7 can be coupled via a key and a keyway to restrict the degree of freedom of relative rotation between the torque transmission structure 7 and the helical motion structure B. Furthermore, the key and keyway can also provide axial motion guidance, ensuring that the rotation of the torque transmission structure 7 is driven as purely as possible by the helical motion structure B, thereby improving the rotational accuracy of the torque transmission structure 7.

[0078] like Figure 3 As shown, the third part of the multi-start lead screw 5 has a lead screw through hole, which is connected to the bottom of the cavity of the second part of the multi-start lead screw 5. The torque transmission structure 7 passes through the lead screw through hole, which has a keyway. The torque transmission structure 7 has a key bar. The keyway and the key bar cooperate to restrict the degree of freedom of relative rotation between the torque transmission structure 7 and the helical motion structure B.

[0079] In some embodiments provided in this application, a lead screw nut 6 can be independently installed inside the housing 8, so that the inner cavity wall of the hollow housing 8 structure A has a track for constraining the spiral motion structure B to perform spiral motion. For example... Figure 4 As shown, the hollow shell structure A 8 may include a shell 8 and a lead screw nut 6. The outer periphery of the lead screw nut 6 engages with the cavity wall of the actuation chamber of the shell 8, restricting the relative rotation and relative axial sliding degrees of freedom between the lead screw nut 6 and the shell 8. The inner wall of the lead screw nut 6 engages with the outer thread of the helical motion structure B, thereby enabling the helical motion structure B to move along a helical trajectory relative to the lead screw nut 6 within the actuation chamber.

[0080] The relative rotational degrees of freedom between the lead screw nut 6 and the housing 8 can be limited by a spline. Figure 4In the illustrated embodiment, the degree of freedom for the lead screw nut 6 and the housing 8 to slide relative to each other axially can be achieved by limiting the lead screw nut 6 on both sides. Specifically, the actuating cavity wall of the housing 8 is provided with a step, and the side of the lead screw nut 6 facing away from the igniter 1 abuts against this step to restrict the degree of freedom for the lead screw nut 6 to move axially away from the igniter 1. The hollow housing 8 structure A also includes a propellant charge 2, located on the side of the housing 8 near the igniter 1. The propellant charge 2 has a power chamber, the opening of which extends into the actuating cavity of the housing 8 and is threadedly fixed. The actuating cavity of the housing 8 and the power chamber of the propellant charge 2 communicate to form the inner cavity of the hollow housing 8 structure A. The end face of the propellant charge 2 near the housing 8 abuts against the lead screw nut 6 to restrict the degree of freedom for the lead screw nut 6 to move axially toward the igniter 1.

[0081] In some embodiments provided in this application, the hollow housing 8 structure A and the restriction of relative axial sliding of the hollow housing 8 structure A can be implemented on the side of the hollow housing 8 structure A away from the igniter 1. For example... Figure 4 As shown, the hollow shell structure A has a limiting through hole at the end opposite to the igniter 1. The limiting through hole communicates with the bottom of the inner cavity of the hollow shell structure A and passes through the torque transmission structure 7. The torque transmission structure 7 has an annular boss, which is housed in the inner cavity of the hollow shell structure A. The outer diameter of the annular boss is larger than the inner diameter of the limiting through hole. The annular boss of the torque transmission structure 7 abuts against the bottom of the inner cavity of the hollow shell structure A, thereby restricting the degree of freedom of the torque transmission structure 7 to move axially toward the igniter 1.

[0082] The primary axial load on the torque transmission structure 7 comes from the thrust output by the igniter 1. In some embodiments, the torque transmission structure 7 can also be limited in the opposite direction to the thrust output by the igniter 1. Figure 4 As shown, on the side of the limiting through hole of the hollow shell 8 structure A away from the annular boss, the torque transmission structure 7 has an annular groove for mounting the shaft elastic retaining ring 11. The outer diameter of the elastic retaining ring 11 is larger than the inner diameter of the limiting through hole, thereby restricting the degree of freedom of the torque transmission structure 7 to move away from the igniter 1 through the shaft elastic retaining ring 11.

[0083] Example 1

[0084] The present invention provides a pyrotechnic rotary drive device based on a multi-start sliding screw, comprising an igniter 1, a charge body 2, a piston 4, a multi-start screw 5, a torque transmission structure 7, and a housing 8.

[0085] The charge body 2 is provided with a power chamber I and two exhaust ports connected to the power chamber I. The igniter 1 is installed on the left side of the charge body 2 and sealed to it. The output end of the igniter 1 is connected to the two exhaust ports to output a high-pressure medium to the power chamber I.

[0086] The housing 8 has an actuating cavity. At the end of the propellant body 2 facing away from the igniter 1, i.e., at the opening of the power chamber I, the opening of the actuating cavity is threadedly fixedly connected to the opening of the power chamber I of the propellant body 2. The cavity formed by the actuating cavity of the housing 8 and the power chamber I of the propellant body 2 is used to accommodate the piston 4 and the multi-start screw 5. Figure 6 As shown, the exterior of the housing 8 may also be provided with mounting lugs 82 or flanges for installation and fixing.

[0087] Piston 4 is a structural component that is closed at one end and open at the other. In the initial state, piston 4 is installed in the power chamber I of the propellant charge 2 and is dynamically sealed to the propellant charge 2 by an O-ring seal 3. The end face of piston 4 at the closed end faces igniter 1. The high-pressure medium output by igniter 1 acts on the end face of piston 4 at the closed end to push piston 4 toward housing 8. In some embodiments, the inner wall of propellant charge 2 may have steps to limit the axial position of piston 4 in the initial state.

[0088] Combination Figure 5 and Figure 8 The multi-start lead screw 5 has a lead screw cavity and a lead screw through hole. The lead screw cavity is located at the end of the multi-start lead screw 5 closest to the igniter 1, and the opening of the lead screw cavity is threadedly fixedly connected to the opening of the piston 4. The cavity at the opening end of the piston 4 is a piston chamber, which communicates with the lead screw cavity. The lead screw through hole of the multi-start lead screw 5 communicates with the bottom of the lead screw cavity and is used for the torque transmission structure 7 to pass through. At the end of the torque transmission structure 7 opposite to the igniter 1, a counterweight 74 or other structure for transmitting torque is provided.

[0089] As previously described, piston 4 can drive the multi-start screw 5 to move towards housing 8. When piston 4 is at its maximum stroke, it remains in contact with the inner wall of the charge body 2 via O-ring 3. The multi-start screw 5 gradually enters the actuating cavity of housing 8 during the driving process. Under the thrust of piston 4, the multi-start screw 5 not only slides relative to housing 8 but also rotates simultaneously due to its helical trajectory. The multi-start screw 5 can slide axially with the torque transmission structure 7, but the degree of freedom for relative rotation between the multi-start screw 5 and the torque transmission structure 7 is restricted (e.g., by...). Figure 7The multi-start screw 5 and torque transmission structure 7 typically have 4 to 8 evenly distributed sliding splines (which can be flexibly selected according to the structural arrangement and output torque). The torque transmission structure 7 and the housing 8 can rotate relative to each other, but the degree of freedom for axial sliding between them is restricted. Therefore, when the multi-start screw 5 rotates, the torque transmission structure 7 can rotate relative to the housing 8 under the drive of the multi-start screw 5. Because the axial movement of the torque transmission structure 7 relative to the housing 8 is restricted, the extent to which the torque transmission structure 7 extends into the space communicating with the piston cavity and the screw cavity gradually increases during rotation.

[0090] In summary, during operation, the igniter 1 discharges high-pressure gas through a small orifice into the power chamber Ⅰ, driving the piston 4 to move towards the housing 8. Under the action of the helical trajectory, the multi-start screw 5 rotates axially and transmits the rotation to the torque transmission structure 7, causing the torque transmission structure 7 to generate pure rotation and output torque. The state after operation is as follows: Figure 10 As shown.

[0091] In some embodiments, such as Figure 8 and Figure 9 As shown, the outer periphery of the multi-start lead screw 5 may have a thread 52. The housing 8 also has a lead screw nut 6 within the actuating cavity. The inner wall of the lead screw nut 6 has a threaded track that mates with the thread 52. The thread 52 and the threaded track can form a multi-start sliding helical pair, thereby creating the aforementioned helical trajectory. Therefore, the multi-start lead screw 5 can rotate relative to the lead screw nut 6 while sliding relative to it. In some other embodiments, the positions of the thread and the threaded track can be reversed.

[0092] exist Figure 8 and Figure 9 In the illustrated embodiment, the helical pair consisting of the multi-start lead screw 5 and the lead screw nut 6 can form a self-locking structure in the initial state. The number of threads 52 is generally 10 to 20, the helix angle of the threads 52 is not less than 50°, and the tooth profile is a 30° standard trapezoidal thread or a rectangular thread.

[0093] In addition, the screw nut 6 and the housing 8 restrict both the axial sliding degree of freedom and the relative rotation degree of freedom, so that the multi-start screw 5 and the housing 8 can slide relative to each other axially and rotate relative to each other, and the multi-start screw 5 can rotate relative to the housing 8 while sliding relative to the housing 8.

[0094] like Figure 5As shown, the inner wall of the actuation cavity of the housing 8 can have a step. During installation, the lead screw nut 6 can be inserted into the opening of the housing 8 facing the piston 4, and the lead screw nut 6 abuts against the step on the inner wall of the housing 8 to restrict the degree of freedom of the lead screw nut 6 to move axially away from the igniter 1. The end of the lead screw nut 6 facing the igniter 1 can be limited by the charge body 2. At the end of the charge body 2 near the housing 8, the outer circumference of the charge body 2 has threads, and the inner side of the actuation cavity of the housing 8 has corresponding threads at the end near the charge body 2. Therefore, when the charge body 2 and the housing 8 are threadedly fixedly connected, the end of the charge body 2 near the housing 8 can extend into the actuation cavity of the housing 8, so that the end face of the charge body 2 near the housing 8 can abut against the lead screw nut 6, thereby restricting the degree of freedom of the lead screw nut 6 to move axially toward the igniter 1.

[0095] The relative rotational freedom between the lead screw nut 6 and the housing 8 is restricted, for example, by a spline. Figure 6 and Figure 9 As shown, the actuating cavity of the housing 8 has multiple keyways 81 evenly distributed at positions corresponding to the lead screw nut 6, and multiple key bars evenly distributed on the outer periphery of the lead screw nut 6, which mate with the multiple keyways 81. The fixing splines between the lead screw nut 6 and the housing 8 are generally 2 to 4 evenly distributed, and can be flexibly selected according to the structural arrangement and output torque. In some other embodiments, the positions of the keyways and key bars can be reversed.

[0096] In some other embodiments, the helical structure that cooperates with the multi-start lead screw 5 can be directly set on the housing 8, thus eliminating the need for the lead screw nut 6.

[0097] In some embodiments, combined with Figure 5 The housing 8 has a limiting through hole at the end opposite to the charge body 2. This limiting through hole communicates with the bottom of the actuation cavity and passes through the torque transmission structure 7. The torque transmission structure 7 may have an annular boss 72 at its middle section. The outer diameter of the annular boss 72 is smaller than the inner diameter of the actuation cavity but larger than the inner diameter of the limiting through hole. Figure 5 In the illustrated embodiment, the annular boss 72 of the torque transmission structure 7 can abut against the bottom of the actuation cavity directly or indirectly (e.g., via the gasket 9), thereby restricting the degree of freedom of the torque transmission structure 7 to move axially toward the igniter 1. The gasket 9 is made of, for example, a high-strength, high-hardness, wear-resistant material, such as 60Si2MnA with HRC≥55, and its surface is sputtered with molybdenum disulfide and coated with grease for protection and lubrication. In addition, on the side of the limiting through hole of the housing 8 opposite to the annular boss 72, the torque transmission structure 7 has an annular groove 73 for mounting a shaft elastic retaining ring 11. The outer diameter of the elastic retaining ring 11 is larger than the inner diameter of the limiting through hole, thereby restricting the degree of freedom of the torque transmission structure 7 to move axially away from the igniter 1.

[0098] In some embodiments, in the initial state, the axial movement and relative rotation of the torque transmission structure 7 relative to the housing 8 can be restricted by the locating pin 10 to achieve initial fixation. Figure 5 and Figure 10 As shown, a positioning pin 10 can be provided at the end of the housing 8 away from the igniter 1. The positioning pin 10 passes laterally through the wall of the limiting through hole of the housing 8 and is inserted into the torque transmission structure 7, thereby restricting its axial movement and rotation, and realizing the initial fixation of the torque transmission structure 7.

[0099] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims of the present invention.

Claims

1. A pyrotechnic rotary drive device for outputting torque, characterized in that, include: Hollow shell structure (A); Ignition device (1), located at one end of hollow shell structure (A), is used to output axial power to the inner cavity of hollow shell structure (A); The spiral motion structure (B) is located in the cavity of the hollow shell structure (A) and is used to move along the spiral trajectory under the power output of the igniter (1), so that the spiral motion structure (B) itself has rotational motion and axial sliding. A torque transmission structure (7) is set on a hollow shell structure (A). The torque transmission structure (7) and the hollow shell structure (A) can rotate relative to each other, but the degree of freedom of relative axial sliding is restricted. A part of the torque transmission structure (7) is connected to a helical motion structure (B). The torque transmission structure (7) and the helical motion structure (B) can slide relative to each other axially, but the degree of freedom of relative rotation is restricted. Thus, the torque transmission structure (7) rotates under the drive of the helical motion structure (B). The other part of the torque transmission structure (7) is located outside the hollow shell structure (A) to output torque.

2. The pyrotechnic rotary drive device according to claim 1, characterized in that, The helical motion structure (B) has a motion cavity, and the torque transmission structure (7) is rod-shaped. The part of the torque transmission structure (7) connected to the helical motion structure (B) extends into the motion cavity, which is used to provide axial relative sliding stroke space for the torque transmission structure (7).

3. The pyrotechnic rotary drive device according to claim 2, characterized in that, The spiral motion structure (B) includes: Piston (4) is used to bear the thrust from igniter (1); The multi-start screw (5) includes a first part, a second part and a third part; the first part of the multi-start screw (5) is used to fix with the piston (4), so that the multi-start screw (5) can move along a helical trajectory relative to the hollow shell structure (A) under the drive of the piston (4); the second part of the multi-start screw (5) is located between the first part and the third part of the multi-start screw (5), the second part of the multi-start screw (5) has a cavity for providing axial relative sliding stroke space for the torque transmission structure (7), and the third part of the multi-start screw (5) is used to cooperate with the torque transmission structure (7) to limit the degree of freedom of relative rotation between the torque transmission structure (7) and the helical motion structure (B).

4. The pyrotechnic rotary drive device according to claim 3, characterized in that, The piston (4) is a structural component that is closed at one end and open at the other end. The piston (4) is positioned facing the igniter (1) at the closed end. The high-pressure medium output by the igniter (1) acts on the closed end face of the piston (4). The multi-start screw (5) has a screw cavity that connects the first part and the second part of the multi-start screw (5). The open end of the piston (4) is threadedly fixed to the open end of the screw cavity. At the end of the axial sliding stroke of the multi-start screw (5), the torque transmission structure (7) gradually penetrates into the opening of the piston (4).

5. The pyrotechnic rotary drive device according to claim 3 or 4, characterized in that, The third part of the multi-start screw (5) has a screw through hole, which is connected to the bottom of the cavity of the second part of the multi-start screw (5). The torque transmission structure (7) passes through the screw through hole, which has a keyway. The torque transmission structure (7) has a key bar. The keyway and key bar cooperate to restrict the degree of freedom of relative rotation between the torque transmission structure (7) and the helical motion structure (B).

6. The pyrotechnic rotary drive device according to any one of claims 1 to 5, characterized in that, The outer periphery of the helical motion structure (B) has threads; the inner cavity wall of the hollow shell structure (A) has a threaded track that matches the threads of the helical motion structure (B), so that the helical motion structure (B) can move relative to the hollow shell structure (A) along a helical trajectory.

7. The pyrotechnic rotary drive device according to claim 6, characterized in that, The hollow shell structure (A) includes: The housing (8) has an actuating cavity; The outer periphery of the lead screw nut (6) is engaged with the cavity wall of the actuation chamber of the housing (8), and restricts the relative rotation and relative axial sliding degrees of freedom between the lead screw nut (6) and the housing (8). The inner wall of the lead screw nut (6) is engaged with the outer periphery of the helical motion structure (B), so that the helical motion structure (B) can move relative to the lead screw nut (6) along a helical trajectory within the actuation chamber.

8. The pyrotechnic rotary drive device according to claim 7, characterized in that, The relative rotational freedom between the lead screw nut (6) and the housing (8) is restricted by a spline; The actuation cavity wall of the housing (8) is provided with a step, and the side of the screw nut (6) away from the igniter (1) abuts against the step to limit the degree of freedom of the screw nut (6) to move axially away from the igniter (1). The hollow shell structure (A) also includes a charge body (2), which is located on the side of the shell (8) near the igniter (1). The charge body (2) is provided with a power chamber. The opening of the power chamber extends into the actuation chamber of the shell (8) and is threadedly fixed. The actuation chamber of the shell (8) and the power chamber of the charge body (2) are connected to form the inner cavity of the hollow shell structure (A). The end face of the charge body (2) near the shell (8) abuts against the lead screw nut (6) to limit the degree of freedom of the lead screw nut (6) to move axially toward the igniter (1).

9. The pyrotechnic rotary drive device according to claim 8, characterized in that, The engagement of the charge body (2) and the piston (4) satisfies at least one of the following: The inner wall of the charge body (2) has steps to limit the axial position of the piston (4) in the initial state; When the piston (4) is at its maximum axial sliding stroke, the piston (4) still engages with the inner wall of the charge body (2) through the O-ring seal.

10. The pyrotechnic rotary drive device according to any one of claims 1 to 9, characterized in that, The hollow shell structure (A) has a limiting through hole at one end away from the igniter (1). The limiting through hole is connected to the bottom of the inner cavity of the hollow shell structure (A) and passes through the torque transmission structure (7). The torque transmission structure (7) has an annular boss, which is housed in the inner cavity of the hollow shell structure (A). The outer diameter of the annular boss is larger than the inner diameter of the limiting through hole. The annular boss of the torque transmission structure (7) abuts against the bottom of the inner cavity of the hollow shell structure (A), thereby restricting the degree of freedom of the torque transmission structure (7) to move axially toward the igniter (1). On the side of the limiting through hole of the hollow shell structure (A) away from the annular boss, the torque transmission structure (7) has an annular groove for mounting a shaft elastic retaining ring (11). The outer diameter of the elastic retaining ring (11) is larger than the inner diameter of the limiting through hole, thereby restricting the degree of freedom of the torque transmission structure (7) to move axially away from the igniter (1) by the shaft elastic retaining ring (11).

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