Self-locking device for a linear lifting system and linear lifting system

Abstract

The utility model discloses a linear lifting system's self -locking device and linear lifting system belong to linear lifting system field, solve the problem that power source needs to overcome the self -locking torsional spring locking force additionally when power source drive output assembly reverse operation, the technical scheme of solving this problem mainly includes coupling drive unit and friction brake unit, and coupling drive unit includes input part and output part, and friction brake unit includes brake torsional spring and torsional spring seat, is used for when the reverse tendency caused by load torque is produced in rotating part to hold tightly torsional spring seat and input part and implements self -locking, first torsional spring foot can be driven by the input part of the input part of the positive direction actuating torque and force torsional spring main body radial expansion, second torsional spring foot can be driven by the input part of the input part of the reverse actuating torque in the relative output part rotation process and force torsional spring main body radial expansion. The utility model output part applies positive or reverse actuating torque, and brake torsional spring all will not produce locking force.

Description

Technical Field

[0001] This utility model demonstrates a self-locking device and a linear lifting system, belonging to the technical field of linear lifting systems. Background Technology

[0002] The main working principle of a linear actuator is to drive a lead screw to rotate through an actuation unit. A nut with a threaded fit is installed on the lead screw. When the lead screw rotates, it drives the nut to reciprocate along the axial direction of the lead screw. The nut converts the rotational force of the lead screw into a linear thrust or pull force. A load inner tube is connected to the nut. The load inner tube reciprocates by extending or retracting with the linear movement of the nut to achieve the purpose of linear actuation.

[0003] If a traditional linear actuator does not have a self-locking mechanism, the locking of the actuator is achieved by the friction between the mechanisms. However, the friction between the mechanisms will reduce the normal operating speed of the linear actuator and increase the load on the actuator unit. In addition, when the linear actuator is heavily loaded, the friction cannot achieve the locking effect, which will cause the linear actuator to fail to lock and automatically reverse.

[0004] In addition, existing technologies include linear actuators with self-locking mechanisms. Such linear actuators typically include a coupling transmission unit, a self-locking mechanism, and an output component. The actuation unit transmits power to the output component through the coupling transmission unit. The self-locking mechanism includes a brake torsion spring, which is fitted around the outer periphery of the coupling transmission unit. Its self-locking mechanism is as follows: when the actuation unit drives the output component to push the load, the brake torsion spring is released in the direction of torque, so the brake torsion spring is essentially non-existent and has no effect; however, when the motor stops, the output shaft will rotate in the opposite direction due to gravity pushed by the load. At this time, the brake torsion spring is locked in the direction of torque, thus locking the coupling transmission unit and achieving the purpose of self-locking.

[0005] The disadvantage of the above self-locking method is that if the actuation unit needs to reverse to retract the load, the brake torsion spring will also lock the coupling transmission unit. The torque output by the actuation unit must be greater than the locking force of the brake torsion spring in order to retract the load, which will increase the additional output torque of the actuation unit. Utility Model Content

[0006] The purpose of this invention is to solve the problem that when the input component drives the output component to run in the reverse direction, it is necessary to overcome the locking force of the brake torsion spring. To this end, a self-locking device and a linear lifting system are provided for the linear lifting system. When the output component is subjected to a positive or negative actuation torque, the brake torsion spring will not generate a locking force.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A self-locking device for a linear lifting system brakes the rotating components used to transmit torque in the linear lifting system. The self-locking device includes:

[0009] The coupled transmission unit includes an input component and an output component arranged coaxially, the input component and the output component are coupled and configured to rotate synchronously after rotating relative to each other by a predetermined angle, and the output component is drivenly connected to the rotating component;

[0010] A friction braking unit includes a braking torsion spring and a torsion spring seat. The torsion spring seat is fixed and cannot be rotated. The braking torsion spring includes a helical torsion spring body, a first torsion spring foot extending from one end of the torsion spring body, and a second torsion spring foot extending from the other end of the torsion spring body. The torsion spring body surrounds the torsion spring seat and the output component, respectively, and is used to lock the torsion spring seat and the output component when the rotating component generates a reversing tendency caused by the load torque. The first torsion spring foot can be driven by the output component with a positive actuation torque to force the torsion spring body to expand radially. The second torsion spring foot can be driven by the input component with a reverse actuation torque during rotation relative to the output component to force the torsion spring body to expand radially.

[0011] The beneficial effects of using this utility model are:

[0012] The self-locking device described in this utility model includes a torsion spring seat and a brake torsion spring. The brake torsion spring is fitted onto the outer periphery of the torsion spring seat and the output component. During the operation of the linear lifting system, the actuation unit outputs a positive actuation torque to the input component, causing the input component to rotate in the forward direction. After the input component rotates by a predetermined angle, it drives the output component to rotate in the forward direction. During the rotation of the output component, the output component applies the positive actuation torque to the first torsion spring foot of the brake torsion spring. Under the action of the positive actuation torque, the brake torsion spring body is forced to expand radially, thereby causing the brake torsion spring to release the output component. At this time, the brake torsion spring does not generate a locking force on the output component. The output component drives the output component to rotate in the forward direction to achieve the purpose of pushing out the load. When the actuation unit stops outputting torque, the output component is pushed in the opposite direction by the load torque. The output component applies the load torque to the first torsion spring foot of the brake torsion spring. Under the action of the load torque, the brake torsion spring body is forced to contract radially, causing the brake torsion spring to simultaneously grip the output component and the torsion spring seat. Since the torsion spring seat is fixed, The rotational nature of the torsion spring allows it to restrict the rotation of the output component, thus achieving a locking effect and preventing the output component from rotating automatically under load torque. This effectively improves the load capacity of the linear lifting system. When the actuation unit outputs a reverse actuation torque to the input component, the input component rotates in the opposite direction. Since the input and output components can rotate relative to each other by a predetermined angle, the input component first rotates relative to the output component. Before the input and output components engage, the input component first acts on the second torsion spring foot of the brake torsion spring. When the input component transmits the reverse actuation torque to the brake torsion spring, the brake torsion spring is forced to expand radially under the action of the reverse actuation torque, which in turn causes the brake torsion spring to release the output component. At this time, the brake torsion spring will not exert a locking force on the output component. Therefore, regardless of whether the input component rotates in the forward or reverse direction, the brake torsion spring is in a released state, which will not generate additional load on the actuation unit. The output torque requirement of the actuation unit is relatively small, and smooth operation in both forward and reverse directions can be achieved.

[0013] Preferably, the output component includes a rotating component and a positioning component. The brake torsion spring is fitted onto the outer periphery of the rotating component, and the positioning component has a positioning part for positioning the first torsion spring foot. The positioning component can be adjusted relative to the rotating component to change the relative position of the positioning part and the rotating component. Using the aforementioned technical solution, the positioning component can be adjusted relative to the rotating component, thereby changing the position of the positioning part. This allows the positioning part to have a larger installation range, reducing the installation requirements for the brake torsion spring and providing a wider placement range for the first torsion spring foot. This reduces the assembly difficulty of the brake torsion spring and also reduces the size requirements of the brake torsion spring itself, enabling the use of brake torsion springs of different sizes and helping to reduce manufacturing and assembly costs.

[0014] Preferably, the positioning member has a first tooth on its outer periphery, and the rotating member has a second tooth that meshes with the first tooth. The positioning member is detachably connected to the rotating member by fasteners. By employing the aforementioned technical solution, the engagement of the first and second teeth allows the positioning member to be adjusted at multiple angles, reducing the minimum adjustable angle and enabling it to accommodate more positions of the first torsion spring feet. This effectively reduces the assembly difficulty and requirements between the positioning member and the brake torsion spring.

[0015] Preferably, one of the first and second teeth is arranged in a ring and continuously, while the other is arranged in a fan shape or a plurality of fan-shaped intervals. Using the aforementioned technical solution, where one of the first and second teeth is a complete circle and the other is not, the contact area between the first and second teeth can be reduced after they mesh, thereby reducing the resistance between them. Therefore, even after the first and second teeth mesh, the positioning member still has a certain swing amplitude, allowing it to be finely adjusted relative to the rotating member, further increasing the adaptability range of the positioning member.

[0016] Preferably, the input component includes a transmission component coupled to the output component. The transmission component has fan-shaped grooves that are concentric with the transmission component. The transmission component also has a slider that slides with the grooves. The slider abuts against the end of the groove to achieve power transmission between the transmission component and the output component.

[0017] Preferably, the transmission component has an abutment portion. The transmission component rotates relative to the output component to move the abutment portion closer to or further away from the second torsion spring foot. The abutment portion abuts against the second torsion spring foot, acting on the brake torsion spring to control the increase of the inner diameter of the brake torsion spring. The distance between the abutment portion and the second torsion spring foot is less than the sliding distance of the slider in the groove. Using the aforementioned technical solution, during the reverse rotation of the transmission component, before the slider abuts against the end of the groove, the abutment portion will preferentially abut against the second torsion spring foot. Therefore, the transmission component will first act on the second torsion spring foot, causing the brake torsion spring to expand radially under the action of the reverse actuating torque, thereby releasing the output component.

[0018] Preferably, the transmission component has a side plate extending axially around its periphery, a brake torsion spring is located inside the side plate, the side plate has a notch, the second torsion spring leg of the brake torsion spring extends into the notch, and one side wall of the notch is the abutment part in the circumferential direction.

[0019] Preferably, the slide groove extends axially through the transmission component, and a washer is installed on the side of the transmission component facing away from the output component. The washer is connected to the slider by bolts to prevent the transmission component from detaching from the output component axially. Using the aforementioned technical solution, the washer connected to the slider by bolts can axially limit the transmission component, preventing it from detaching from the output component axially and ensuring a more stable and reliable connection between the transmission component and the output component. Furthermore, the washer can isolate the bolt from direct contact with the transmission component, reducing the possibility of damage to the transmission component due to the bolts, and thus protecting the transmission component.

[0020] This utility model also demonstrates a linear lifting system, including:

[0021] The actuation unit can selectively output positive actuation torque and reverse actuation torque;

[0022] The lifting unit includes a telescopic sleeve assembly and a transmission assembly that drives the telescopic sleeve assembly.

[0023] The power transmission chain is configured to transmit the output torque of the actuator unit to the drive assembly;

[0024] The self-locking device described in any of the above items constitutes part of the force transmission chain.

[0025] Preferably, the actuation unit includes a motor housing and a motor built into the motor housing; the transmission assembly includes a lead screw and a nut; the nut is driven by the rotation of the lead screw to move the telescopic sleeve assembly; the force transmission chain also includes a reduction mechanism; the output end of the reduction mechanism is connected to the input component of the self-locking device; the lead screw is connected to the output component of the self-locking device as a rotating component; and the torsion spring seat is fixed to the motor housing.

[0026] Preferably, the linear lifting system includes a lifting platform and two lifting units. The actuation unit includes a hand crank. The transmission assembly of each lifting unit includes a lead screw and a nut. The nut is driven by the rotation of the lead screw to move the telescopic sleeve assembly. The force transmission chain also includes a drive shaft, a synchronous shaft, a first gearbox, and a second gearbox. The hand crank is used to drive the drive shaft. The drive shaft and the synchronous shaft are connected by transmission through the first gearbox. The two ends of the synchronous shaft are respectively connected to the second gearbox. The second gearbox is connected to the lead screw. One of the drive shaft, synchronous shaft, and lead screw is connected to the self-locking device as a rotating component.

[0027] Other features and advantages of this utility model will be disclosed in detail in the following specific embodiments and accompanying drawings. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings:

[0029] Figure 1This is a schematic diagram of the self-locking device of the linear lifting system of this utility model;

[0030] Figure 2 This is a cross-sectional view of the self-locking device of the linear lifting system of this utility model;

[0031] Figure 3 This is an exploded view of the self-locking device of the linear lifting system of this utility model;

[0032] Figure 4 This is a schematic diagram of the output component and brake torsion spring in the self-locking device of the linear lifting system of this utility model;

[0033] Figure 5 This is a schematic diagram of the input component in the self-locking device of the linear lifting system of this utility model;

[0034] Figure 6 This is a schematic diagram of the coupling transmission unit and friction braking unit in the self-locking device of the linear lifting system of this utility model;

[0035] Figure 7 This is a schematic diagram of the output component in the self-locking device of the linear lifting system of this utility model;

[0036] Figure 8 This is a schematic diagram of the linear lifting system in Embodiment 2 of this utility model;

[0037] Figure 9 This is a partial schematic diagram of the height-adjustable table in Embodiment 3 of this utility model.

[0038] Reference numerals: 1. Actuating unit; 2. Self-locking device; 20. Input shaft; 21. Transmission component; 211. Slide groove; 212. Abutment part; 213. Side plate; 214. Notch; 221. Rotating component; 2211. Slider; 2212. Second tooth; 2213. Protrusion; 222. Positioning component; 223. Positioning part; 224. First tooth; 225. Fastener; 23. Output component; 231. Positioning groove; 24. Washer; 25. Bolt; 31. Transmission shaft; 32. Synchronous shaft; 4. Brake torsion spring; 40. Torsion spring body; 41. First torsion spring foot; 42. Second torsion spring foot; 43. Torsion spring seat; 5. Telescopic sleeve assembly; 6. Motor box; 8. Lifting platform; 81. Mounting base. Detailed Implementation

[0039] The technical solutions of the present utility model will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present utility model.

[0040] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0041] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0042] Example 1:

[0043] like Figures 1 to 7 As shown in the figure, this embodiment illustrates a self-locking device 2 for a linear lifting system, which brakes the rotating components used to transmit torque in the linear lifting system. The self-locking device 2 includes:

[0044] The coupled transmission unit includes an input component and an output component arranged coaxially, the input component and the output component are coupled and configured to rotate synchronously after rotating relative to each other by a predetermined angle, and the output component is drivenly connected to the rotating component;

[0045] The friction braking unit includes a braking torsion spring 4 and a torsion spring seat 43. The torsion spring seat 43 is fixed and cannot be rotated. The braking torsion spring 4 includes a helical torsion spring body 40, a first torsion spring foot 41 extending from one end of the torsion spring body 40, and a second torsion spring foot 42 extending from the other end of the torsion spring body. The torsion spring body surrounds the torsion spring seat 43 and the output component, respectively, and is used to lock the torsion spring seat 43 and the output component when the rotating component generates a reversing tendency caused by the load torque. The first torsion spring foot 41 can be driven by the output component that applies a positive actuating torque to force the torsion spring body to expand radially. The second torsion spring foot 42 can be driven by the input component that applies a reverse actuating torque during rotation relative to the output component to force the torsion spring body to expand radially.

[0046] In this embodiment, the self-locking device 2 includes a torsion spring seat 43 and a brake torsion spring 4. The brake torsion spring 4 is fitted onto the outer periphery of the torsion spring seat 43 and the output component. During the operation of the linear lifting system, the actuation unit 1 outputs a positive actuation torque to the input component, causing the input component to rotate in the forward direction. After the input component rotates by a predetermined angle, it drives the output component to rotate in the forward direction. During the rotation of the output component, the output component applies a positive actuation torque to the first torsion spring foot 41 of the brake torsion spring 4. Under the action of the positive actuation torque, the brake torsion spring 4 forces the torsion spring body to expand radially, thereby causing the brake torsion spring 4 to release the output component. At this time, the brake torsion spring 4 does not generate a locking force on the output component. The output component drives the output component to rotate in the forward direction to achieve the purpose of pushing out the load. When the actuation unit 1 stops outputting torque, the output component is pushed in the opposite direction by the load torque. The output component applies the load torque to the first torsion spring foot 41 of the brake torsion spring 4. Under the action of the load torque, the brake torsion spring 4 forces the torsion spring body to contract radially, so that the brake torsion spring 4 simultaneously hugs the output component and the torsion spring seat 43. 3 is fixed and cannot be rotated. Therefore, the clamping force of the brake torsion spring 4 can limit the rotation of the output component, thereby achieving the purpose of locking and preventing the output component from rotating automatically under the action of load torque. This can effectively improve the load capacity of the linear lifting system. When the actuation unit 1 outputs a reverse actuation torque to the input component, the input component rotates in the reverse direction. Since the input component and the output component can rotate relative to each other by a predetermined angle, the input component first rotates relative to the output component. Before the input component and the output component are engaged, the input component first acts on the second torsion spring foot 42 of the brake torsion spring 4. When the input component transmits the reverse actuation torque to the brake torsion spring 4, the brake torsion spring 4 is forced to expand radially under the action of the reverse actuation torque. This will also cause the brake torsion spring 4 to release the output component. At this time, the brake torsion spring 4 will not generate a locking force on the output component. Therefore, no matter whether the input component rotates in the forward or reverse direction, the brake torsion spring 4 is in the released state and will not generate an additional load on the actuation unit 1. The output torque requirement of the actuation unit 1 is small, and smooth operation in both forward and reverse directions can be achieved.

[0047] like Figure 2 and Figure 3As shown, in this embodiment, the input component includes an input shaft 20 and a transmission component 21. The input shaft 20 is connected to the transmission component 21, and the transmission component 21 rotates synchronously with the input shaft 20. The output component includes a rotating component 221, a positioning component 222, and an output component 23. The positioning component 222 is fixed to the rotating component 221. The rotating component 221 is connected to the output component 23, and the rotating component 221 rotates synchronously with the output component 23. The output component 23 is connected to the rotating component, and the rotating component rotates synchronously with the output component 23. In addition, the torsion spring seat 43 remains fixed and cannot rotate. The torsion spring seat 43 has a circular fixing part. The outer diameter of the fixing part is equal to the outer diameter of the rotating component 221. The fixing part has a through hole. The output component 23 passes through the fixing part along the through hole and is connected to the rotating component 221. The brake torsion spring 4 is simultaneously fitted on the outer periphery of the rotating component 221 and the fixing part. When the torsion spring body of the brake torsion spring 4 contracts radially, the brake torsion spring 4 simultaneously hugs the rotating component 221 and the fixing part.

[0048] Other examples Figure 7 As shown, in this embodiment, the top of the output component 23 is provided with several positioning grooves 231, and the bottom of the rotating component 221 is provided with several protrusions 2213. When the rotating component 221 is connected to the output component 23, the protrusions 2213 are embedded in the positioning grooves 231, thereby realizing the transmission connection between the rotating component 221 and the transmission shaft 31, so that the transmission shaft 31 can rotate synchronously with the rotating component 221.

[0049] like Figure 4 and Figure 5 As shown, in this embodiment, the transmission component 21 is provided with a slide groove 211, and the rotating component 221 is provided with a slider 2211 that slides in cooperation with the slide groove 211. The slide groove 211 is generally fan-shaped, and the slide groove 211 and the transmission component 21 are set on the same axis. During the sliding of the slider 2211 along the slide groove 211, the slider 2211 rotates around the input shaft 20, that is, the transmission component 21 and the rotating component 221 rotate relative to each other. When the slider 2211 abuts against the end of the slide groove 211, the transmission component 21 continues to rotate, which can drive the rotating component 221 to rotate synchronously, thereby realizing the power transmission between the transmission component 21 and the rotating component 221.

[0050] like Figure 3 and Figure 6As shown, in this embodiment, the slide groove 211 is disposed at the top of the transmission member 21, and the slide groove 211 extends through the transmission member 21 axially. The transmission member 21 is provided with a plurality of slide grooves 211, which are spaced apart around the circumference of the input shaft 20. The corresponding rotating member 221 is provided with a number of sliders 2211 equal to the number of slide grooves 211. After the transmission member 21 and the rotating member 221 are assembled, the sliders 2211 extend into the slide grooves 211 to achieve sliding engagement between the sliders 2211 and the slide grooves 211. In addition, the top of the slider 2211 is provided with a threaded hole. A washer 24 is installed on the side of the transmission member 21 facing away from the rotating member 221. A bolt 25 passes through the washer 24 and is threadedly connected to the slider 2211. The head of the bolt 25 is aligned with the washer. The ring 24 forms a limit, and the bolt 25 is connected to the slider 2211 with a washer 24 which is restricted to the top surface of the transmission component 21. The washer 24 can axially limit the transmission component 21, preventing the transmission component 21 from detaching from the rotating component 221 axially, and ensuring a more stable and reliable connection between the transmission component 21 and the rotating component 221. In addition, the washer 24 can isolate the direct contact between the bolt 25 and the transmission component 21, reducing the possibility of damage to the transmission component 21 due to the bolt 25. The washer 24 can protect the transmission component 21. Secondly, the multiple sliders 2211 and grooves 211 can make the relative rotation of the transmission component 21 and the rotating component 221 smoother and more fluid, and can also limit the positional displacement of the transmission component 21 and the rotating component 221.

[0051] like Figure 3 As shown, in this embodiment, the upper end of the brake torsion spring 4 is bent to form a first torsion spring foot 41, and the lower end of the brake torsion spring 4 is bent to form a second torsion spring foot 42. Both the first torsion spring foot 41 and the second torsion spring foot 42 are bent outward. The rotating member 221 has a positioning part 223, which is provided with a positioning groove 231 for the first torsion spring foot 41 to be inserted. The first torsion spring foot 41 is connected to the rotating member 221 through the positioning part 223. The transmission member 21 has an abutment part 212. When the actuating unit 1 drives the transmission member... When the transmission member 21 rotates in the forward direction and the rotating member 221 rotates relative to each other, the abutment part 212 moves away from the second torsion spring foot 42. When the actuation unit 1 drives the transmission member 21 to rotate in the reverse direction and the transmission member 21 rotates relative to each other, the abutment part 212 moves closer to the second torsion spring foot 42. The abutment part 212 abuts against the second torsion spring foot 42 and transmits the torque to the brake torsion spring 4, thereby forcing the torsion spring body 40 to expand radially so that the brake torsion spring 4 releases the rotating member 221 and the torsion spring seat 43.

[0052] It should be noted that, in this embodiment, the transmission component 21 is provided with a side plate 213 extending axially, and the brake torsion spring 4 is located inside the side plate 213. The side plate 213 is provided with a notch 214, and the second torsion spring foot 42 of the brake torsion spring 4 extends into the notch 214. In the circumferential direction, one side wall of the notch 214 is the abutment portion 212. When the transmission component 21 rotates forward until the slider 2211 abuts against the slide groove 211, there is a gap between the abutment portion 212 and the second torsion spring foot 42. The distance between 2 is less than the sliding distance of slider 2211 in the groove 211. That is, after the transmission member 21 rotates in the opposite direction, before the slider 2211 and the end of the groove 211 abut against each other, the abutting part 212 will abut against the second torsion spring foot 42 first. Therefore, the upper rotating member 221 will abut against the second torsion spring foot 42 first, so that the transmission member 21 transmits the reverse actuation torque to the brake torsion spring 4 through the second torsion spring foot 42. Under the action of the reverse actuation torque, the inner diameter of the brake torsion spring 4 will gradually increase, thereby releasing the lower rotating member 221 and the torsion spring seat 43.

[0053] like Figure 3 and Figure 4 As shown, in this embodiment, the rotating component 221 includes a rotating component 221 and a positioning component 222. The positioning component 222 is generally circular, and a first tooth 224 is provided on the outer periphery of the positioning component 222. The center of the rotating component 221 is recessed to form a groove, and the inner wall of the groove is provided with a second tooth 2212 that meshes with the first tooth 224. The positioning component 222 is detachably connected to the rotating component 221 by a fastener 225. The circumference of the positioning component 222 extends radially outward to form the positioning part 223. The positioning component 222 can be adjusted relative to the rotating component 221, thereby changing the position of the positioning part 223 and giving the positioning part 223 a larger installation range. This reduces the installation requirements for the brake torsion spring 4, allowing the first torsion spring foot 41 to have a wider placement range, thereby reducing the assembly difficulty of the brake torsion spring 4. It also reduces the size requirements for the brake torsion spring 4 itself, making it suitable for brake torsion springs 4 of different sizes, which helps to reduce manufacturing and assembly costs. In addition, through the cooperation of the first tooth 224 and the second tooth 2212, the positioning member 222 has multi-angle adjustment, which reduces the minimum adjustable angle of the positioning member 222, allowing the positioning member 222 to adapt to more positions of the first torsion spring foot 41, thereby effectively reducing the assembly difficulty and assembly requirements of the positioning member 222 and the brake torsion spring 4.

[0054] In this embodiment, the first tooth 224 is fan-shaped, meaning it is not a complete circle, while the second tooth 2212 is annular and continuously distributed, meaning it is a complete circle. When the first tooth 224 and the second tooth 2212 mesh, the contact area between them can be reduced, thereby reducing the resistance between them. Therefore, after the first tooth 224 and the second tooth 2212 mesh, the positioning member 222 still has a certain swing amplitude, allowing it to be finely adjusted relative to the rotating member 221, which further increases the adaptability range of the positioning member 222.

[0055] It is understandable that in other embodiments, the first tooth 224 can be a complete circle, while the second tooth 2212 can be distributed in a fan shape.

[0056] It is understandable, of course, that in other embodiments the first tooth 224 may also be formed by a plurality of fan-shaped intervals.

[0057] In this embodiment, the input shaft 20 is a non-circular structure. The input shaft 20 and the transmission component 21 form an anti-rotation fit, thereby enabling the input shaft 20 and the transmission component 21 to rotate synchronously to achieve power transmission. In addition, in this embodiment, the input shaft 20 and the transmission component 21 are an integral structure, which can effectively improve the connection stability between the input shaft 20 and the transmission component 21 and reduce energy loss during the transmission process.

[0058] It is understandable that, in other embodiments, the input shaft 20 and the transmission component 21 may also be a separate structure.

[0059] Example 2:

[0060] like Figure 8 As shown in the figure, this embodiment demonstrates a linear lifting system, including an actuation unit 1, a lifting unit, and a transmission chain. The actuation unit 1 can selectively output positive and negative actuation torques. The lifting unit includes a telescopic sleeve assembly 5 and a transmission assembly that drives the telescopic sleeve assembly 5. The telescopic sleeve assembly 5 includes an inner tube and at least one outer tube that is slidably fitted outside the inner tube. The transmission chain transmits the output torque of the actuation unit 1 to the transmission assembly. In addition, the linear lifting system in this embodiment is a lifting column. The linear lifting system also includes a motor box 6 and a motor built into the motor box 6. The transmission assembly includes a lead screw and a nut. The rotation of the lead screw drives the nut to reciprocate along the axial direction to drive the relative extension and retraction of the inner and outer tubes. The transmission chain also includes a reduction mechanism. The output end of the reduction mechanism is connected to the input component of the self-locking device 2. The lead screw, as a rotating component, is connected to the output component of the self-locking device 2. The torsion spring seat 43 is fixed to the motor box 6.

[0061] Example 3:

[0062] like Figure 9 As shown, the main difference between this embodiment and Embodiment 2 is that, in this embodiment, the linear lifting system is a height-adjustable table. The linear lifting system includes a lifting platform 8 and two lifting units. The actuation unit 1 includes a hand crank. The transmission assembly of each lifting unit includes a lead screw and a nut. The rotation of the lead screw drives the nut to reciprocate along the axial direction, thereby driving the relative extension and contraction of the inner and outer tubes. In addition, the force transmission chain in this embodiment also includes a transmission shaft 31, a synchronous shaft 32, a first gearbox, and a second gearbox. The hand crank is used to drive the transmission shaft 31. The transmission shaft 31 and the synchronous shaft 32 are connected by transmission through the first gearbox. The two ends of the synchronous shaft 32 are respectively connected to the second gearbox. The second gearbox is connected to the lead screw. The synchronous shaft 32 drives the two lifting units to move synchronously. In this embodiment, the transmission shaft 31 is connected to the self-locking device 2 as a rotating component. The bottom of the lifting platform 8 is provided with a mounting base 81. The torsion spring seat 43 of the self-locking device 2 is fixedly connected to the mounting base 81 to limit the rotation of the torsion spring seat 43. The output end of the hand crank is connected to the input component of the self-locking device 2, and the output component of the self-locking device 2 is connected to the transmission shaft 31.

[0063] It is understandable that in other embodiments, the input component of the self-locking device 2 may also be connected to the transmission shaft 31, and the input component and the transmission shaft 31 may be coaxially arranged. The output component of the self-locking device 2 may be connected to the synchronous shaft 32 through the first gearbox.

[0064] It is understandable that in other embodiments, the synchronous shaft 32 can also be used as a rotating component, the self-locking device 2 can be fixed to the lower side of the lifting platform 8 via the mounting base 81, the torsion spring seat 43 of the self-locking device 2 can be fixedly connected to the mounting base 81, the transmission shaft 31 can be driven to the input component of the self-locking device 2 via the first gearbox, and the output component of the self-locking device 2 can be driven to the synchronous shaft 32; or, the input component can be connected to the synchronous shaft 32, and the output component can be driven to the lead screw via the second gearbox.

[0065] Of course, it is understandable that in other embodiments, the lead screw can also be used as a rotating component, the synchronous shaft 32 is connected to the input component of the self-locking device 2 through the second gearbox, the output component of the self-locking device 2 is connected to the lead screw, and the output component is coaxial with the lead screw; it should be noted that in this embodiment, there are two self-locking devices 2 and correspondingly configured on the lead screws of the two transmission assemblies.

[0066] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Those skilled in the art should understand that this utility model includes, but is not limited to, the content described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of this utility model will be included within the scope of the claims.

Claims

1. A self-locking device for a linear lifting system, used to brake rotating components in the linear lifting system that transmit torque, characterized in that, The self-locking device includes: The coupled transmission unit includes an input component and an output component arranged coaxially, the input component and the output component are coupled and configured to rotate synchronously after rotating relative to each other by a predetermined angle, and the output component is drivenly connected to the rotating component; A friction braking unit includes a braking torsion spring and a torsion spring seat. The torsion spring seat is fixed and cannot be rotated. The braking torsion spring includes a helical torsion spring body, a first torsion spring foot extending from one end of the torsion spring body, and a second torsion spring foot extending from the other end of the torsion spring body. The torsion spring body surrounds the torsion spring seat and the output component, respectively, and is used to lock the torsion spring seat and the output component when the rotating component generates a reversing tendency caused by the load torque. The first torsion spring foot can be driven by the output component with a positive actuation torque to force the torsion spring body to expand radially. The second torsion spring foot can be driven by the input component with a reverse actuation torque during rotation relative to the output component to force the torsion spring body to expand radially.

2. The self-locking device of the linear lifting system according to claim 1, characterized in that, The output component includes a rotating component and a positioning component. A brake torsion spring is fitted on the outer periphery of the rotating component. The positioning component has a positioning part for positioning the first torsion spring foot. The positioning component can be adjusted relative to the rotating component to change the relative position between the positioning part and the rotating component.

3. The self-locking device of the linear lifting system according to claim 2, characterized in that, The positioning member has a first tooth on its outer periphery, and the rotating member has a second tooth that meshes with the first tooth. The positioning member is detachably connected to the rotating member by fasteners.

4. The self-locking device of the linear lifting system according to claim 3, characterized in that, One of the first tooth and the second tooth is arranged in a ring and continuously, while the other is arranged in a fan shape or is arranged in several fan-shaped intervals.

5. The self-locking device of the linear lifting system according to claim 1, characterized in that, The input component includes a transmission component coupled to the output component. The transmission component has fan-shaped grooves that are concentric with the transmission component. The transmission component has a slider that slides in cooperation with the grooves. The slider abuts against the end of the groove to realize the power transmission between the transmission component and the output component.

6. The self-locking device of the linear lifting system according to claim 5, characterized in that, The transmission component is provided with an abutting part. The transmission component rotates relative to the output component to drive the abutting part to approach or move away from the second torsion spring foot. The abutting part and the second torsion spring foot act against the brake torsion spring to control the inner diameter of the brake torsion spring to increase. The distance between the abutting part and the second torsion spring foot is less than the sliding distance of the slider in the groove.

7. The self-locking device of the linear lifting system according to claim 6, characterized in that, The transmission component has a side plate extending axially around its periphery, and a brake torsion spring is located inside the side plate. The side plate has a notch, and the second torsion spring leg of the brake torsion spring extends into the notch. In the circumferential direction, one of the side walls of the notch is the abutment part.

8. The self-locking device of the linear lifting system according to claim 5, characterized in that, The slide groove passes through the transmission component axially. A washer is installed on the side of the transmission component facing away from the output component. The washer is connected to the slider by bolts to prevent the transmission component from detaching from the output component axially.

9. A linear lifting system, including: The actuation unit can selectively output positive actuation torque and reverse actuation torque; The lifting unit includes a telescopic sleeve assembly and a transmission assembly that drives the telescopic sleeve assembly. The power transmission chain is configured to transmit the output torque of the actuator unit to the drive assembly; The self-locking device described in any one of claims 1 to 8 is characterized in that it constitutes part of the force transmission chain.

10. The linear lifting system according to claim 9, characterized in that, The actuation unit includes a motor housing and a motor built into the motor housing. The transmission assembly includes a lead screw and a nut. The nut is driven by the rotation of the lead screw to move the telescopic sleeve assembly. The force transmission chain also includes a reduction mechanism. The output end of the reduction mechanism is connected to the input component of the self-locking device. The lead screw is connected to the output component of the self-locking device as a rotating component. The torsion spring seat is fixed to the motor housing.

11. The linear lifting system according to claim 9, characterized in that, The linear lifting system includes a lifting platform and two lifting units. The actuation unit includes a hand crank. The transmission assembly of each lifting unit includes a lead screw and a nut. The nut is driven by the rotation of the lead screw to move the telescopic sleeve assembly. The force transmission chain also includes a drive shaft, a synchronous shaft, a first gearbox, and a second gearbox. The hand crank is used to drive the drive shaft. The drive shaft and the synchronous shaft are connected by transmission through the first gearbox. The two ends of the synchronous shaft are respectively connected to the second gearbox. The second gearbox is connected to the lead screw. One of the drive shaft, synchronous shaft, and lead screw is connected to a self-locking device as a rotating component.

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