Self-locking device for driving motor and self-locking driving motor

Abstract

The utility model discloses a self-locking device for a driving motor and a self-locking driving motor, the self-locking device comprises a cover body, an elastic piece, a driving piece and a friction assembly arranged in the cover body, the friction assembly is sleeved on the tail end of a rotating shaft of the driving motor, the friction assembly comprises a plurality of static friction plates and a plurality of dynamic friction plates, the static friction plates and the dynamic friction plates are sequentially and alternately stacked in the axial direction of the driving motor rotating shaft, the static friction plates are limited in the cover body in the circumferential direction, the dynamic friction plates and the driving motor rotating shaft synchronously rotate, and the dynamic friction plates are provided with sliding gaps. The elastic piece is used for mutually pressing the static friction plate and the dynamic friction plate; the driving piece is used for enabling the elastic piece to be in a compressed state or a released state, and in the compressed state, the driving motor is in a non-self-locking state; and in the release state, the driving motor is in a self-locking state. The self-locking device for the driving motor and the self-locking driving motor are high in self-locking capacity, not prone to failure and high in self-locking stability.

Description

Technical Field

[0001] This application relates to the field of motor technology, specifically to a self-locking device for driving a motor and a self-locking drive motor. Background Technology

[0002] Electric height-adjustable furniture, such as electric height-adjustable desks, electric height-adjustable beds, electric ceiling shelves, and electric height-adjustable supports, mostly uses a drive motor as the power source to drive the height adjustment. Taking an electric height-adjustable desk as an example, its height-adjustable legs are connected to a screw and nut assembly that is transmitted to the output end of the drive motor. This screw and nut assembly is connected to the telescopic tube of the height-adjustable leg. The drive motor drives the screw of the screw and nut assembly to rotate, thereby causing the transmission nut of the screw and nut assembly to drive the telescopic tube of the height-adjustable leg to extend or retract, making the tabletop rise or fall.

[0003] In order to prevent the electric height-adjustable desks mentioned above from automatically sinking due to excessive load on the desk when the drive motor stops working, a self-locking device is generally installed at the output end of the drive motor. If the desk is overloaded or experiences sudden vibration, the transmission nut on the telescopic tube of the height-adjustable desk leg will drive the lead screw to rotate. At the same time, this will drive the worm gear, worm transmission mechanism between the lead screw and nut assembly and the drive motor, as well as the drive motor shaft, to rotate. However, at this time, the self-locking force applied by the self-locking device to the drive motor shaft is greater than the rotational force of the shaft, thus locking the lead screw to prevent the desk from automatically descending. This self-locking device generally uses a torsion spring sleeved on the drive motor shaft to achieve self-locking of the motor shaft, such as the self-locking device disclosed in the applicant's prior Chinese patent application with publication number CN218185898U entitled "A Self-locking Lifting Column". However, because the effective contact area between the torsion spring and the drive motor shaft is small during the self-locking process, the self-locking force is insufficient and it is easily damaged by friction and fails.

[0004] For example, the applicant's prior Chinese patent application, with publication number CN222031767U and titled "A Driving Device for a Height-Adjustable Desk and a Height-Adjustable Desk," discloses a self-locking device comprising an electromagnetic coil, a spring, a fixing plate, and a rear cover connected to the tail end of a motor. The fixing plate is sleeved on the tail end of the motor shaft, and the spring causes the fixing plate to always have a tendency to press against the inner wall of the rear cover. When the electromagnetic coil is energized, it generates magnetic force that compresses the spring, thereby causing the fixing plate to disengage from the inner wall of the rear cover, and the motor shaft is in a non-self-locking state. When the electromagnetic coil is de-energized, the fixing plate, under the elastic force of the spring, is tightly pressed against the inner wall of the rear cover, so that the motor shaft is in a self-locking state.

[0005] The self-locking device of the drive motor mentioned above has the following defects in actual use: the self-locking device achieves self-locking of the motor shaft by generating friction between the fixed plate and the inner wall of the rear cover or by generating friction between the friction plate and the inner wall of the rear cover. Therefore, the contact area between the fixed plate or friction plate and the inner wall of the rear cover is small, resulting in insufficient self-locking force. Moreover, the inner wall of the rear cover is easily worn down due to the rotational friction of the fixed plate or friction plate, causing the self-locking to fail. The self-locking stability is poor and its service life is affected. Utility Model Content

[0006] The technical problem to be solved by this application is to overcome the defects of the above-mentioned related technologies and provide a self-locking device for drive motors with strong self-locking ability, low failure rate and high self-locking stability.

[0007] The technical solution of this application is to provide a self-locking device for a drive motor having the following structure: including...

[0008] The cover is connected to the tail of the drive motor;

[0009] A friction assembly is disposed within the cover body and sleeved on the tail end opposite to the output end of the drive motor shaft. The friction assembly includes multiple static friction plates and multiple dynamic friction plates, which are arranged alternately in sequence along the axial direction of the drive motor shaft. The static friction plates are circumferentially limited within the cover body, and the dynamic friction plates rotate synchronously with the drive motor shaft, and the dynamic friction plates have a sliding gap along the axial direction.

[0010] An elastic element, connected to the cover body, is used to ensure that the static friction plate and the dynamic friction plate always have a tendency to press against each other.

[0011] A driving component, drivenly connected to the elastic element, is used to put the elastic element into a compressed state or a released state. In the compressed state, the static friction plate and the dynamic friction plate are separated from each other, so that the driving motor is in a non-self-locking state; in the released state, the static friction plate and the dynamic friction plate are pressed together, so that the driving motor is in a self-locking state.

[0012] In some embodiments, a pressure plate is provided between the friction assembly and the elastic member, the elastic member abuts against the pressure plate, and the pressure plate is used to press the friction assembly axially. The driving member is drivenly connected to the pressure plate and is used to drive the pressure plate to move axially away from the friction assembly to compress the elastic member.

[0013] In some embodiments, the driving element is an electromagnetic coil connected to the cover body. The electromagnetic coil is disposed on the side of the pressure plate away from the friction assembly. The pressure plate is made of a magnetically conductive material. When the electromagnetic coil is energized, it magnetically attracts the pressure plate to compress the elastic element. When the electromagnetic coil is de-energized, the elastic element is released so that the pressure plate presses the friction assembly, thereby pressing the static friction plate and the dynamic friction plate together.

[0014] In some embodiments, the electromagnetic coil, the elastic element, and the pressure plate are disposed on the side of the cover away from the drive motor relative to the friction assembly.

[0015] In some embodiments, the cover has a hollow support seat along the axial direction at its center, the electromagnetic coil is wound around the support seat, the elastic element is disposed in the inner hole of the support seat, one end of the elastic element abuts against the inner wall of the inner hole of the support seat, and the other end abuts against the pressure plate, so that the pressure plate always has a tendency to press the friction assembly.

[0016] In some embodiments, the free end face of the support is provided with a protruding soft buffer pad, and the pressure plate abuts against the buffer pad when the electromagnetic coil is energized and moves away from the friction assembly.

[0017] In some embodiments, the cover includes a first housing connected to the tail of the drive motor and a second housing connected to the first housing. The friction assembly and the pressure plate are sequentially disposed in the first housing. The second housing has a limiting step at one end near the first housing for the pressure plate to abut against it.

[0018] In some embodiments, the distance from the free end face of the support to the pressure plate is less than the distance from the limiting step to the pressure plate.

[0019] In some embodiments, the two end faces of the static friction plate are respectively provided with a plurality of radial grooves along the circumference, and a friction area that contacts the dynamic friction plate is formed between two adjacent radial grooves; the inner wall of the central hole of the static friction plate does not contact the tail end of the drive motor shaft.

[0020] In summary, the self-locking device for a drive motor disclosed in this application has the following advantages compared with related technologies: the friction assembly of the self-locking device for a drive motor is sleeved on the tail end of the drive motor shaft, and the friction assembly includes multiple static friction plates and multiple dynamic friction plates, which are arranged alternately in the axial direction. The static friction plates are circumferentially limited within the cover body, and the dynamic friction plates rotate synchronously with the drive motor shaft and have a sliding gap in the axial direction. Under the action of the elastic element, the static friction plates and dynamic friction plates can always be pressed against each other to generate friction force, thereby self-locking the drive motor shaft. When releasing the self-lock, it is only necessary to compress the elastic element in the direction away from the friction assembly so that the elastic element is in a compressed state. At the same time, the force applied by the elastic element to the friction assembly disappears, thereby releasing the elastic force applied by the elastic element to the friction assembly, so that there is no axial pressure between the dynamic friction plates and the static friction plates, and the self-locking of the drive motor shaft is released. The friction assembly of this self-locking device uses multiple static friction plates and multiple dynamic friction plates arranged alternately along the axial direction. During self-locking, each dynamic friction plate is pressed against its adjacent static friction plate to generate friction. Therefore, the contact area between the dynamic and static friction plates of this self-locking device for the drive motor is large, and a large friction force can be generated during self-locking, thus making its self-locking ability strong and its self-locking stability high. Even if one friction plate is worn and fails, it will not affect the friction force between other friction plates. Therefore, this self-locking device is not prone to failure and has a long service life.

[0021] Another technical solution of this application is to provide a self-locking drive motor with the following structure: including the self-locking device for drive motors described in any of the above embodiments. This self-locking drive motor uses the self-locking device of the above embodiments, thus making the self-locking drive motor have strong self-locking capability, and the self-locking device is not prone to failure and has high self-locking stability. Attached Figure Description

[0022] Figure 1 This is a structural schematic diagram of a self-locking drive motor according to some embodiments of this application.

[0023] Figure 2 This is a cross-sectional structural schematic diagram of a self-locking device for a drive motor according to some embodiments of this application.

[0024] Figure 3 This is a schematic diagram of the mounting structure of a self-locking device for a drive motor according to some embodiments of this application.

[0025] Figure 4 This is a schematic diagram of another angle mounting structure of a self-locking device for a drive motor according to some embodiments of this application.

[0026] Figure 5 This is a perspective view of a friction assembly of a self-locking device for a drive motor according to some embodiments of this application.

[0027] Figure 6 This is a schematic diagram of the assembly structure of the friction assembly of a self-locking device for a drive motor according to some embodiments of this application.

[0028] Figure 7 This is a schematic diagram of the static friction pad of a friction assembly according to some embodiments of this application.

[0029] Figure 8 This is a schematic diagram of the structure of the moving friction pad of a friction assembly according to some embodiments of this application.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Drive motor; 100. Rotating shaft; 101. Output end; 102. Tail end; 103. Flat cut surface; 2. Cover; 200. First housing; 201. Second housing; 202. Support base; 203. Limiting step; 3. Friction assembly; 300. Static friction plate; 301. Dynamic friction plate; 302. Radial groove; 303. Center hole; 304. Mounting hole; 4. Elastic element; 5. Pressure plate; 6. Electromagnetic coil; 7. Buffer pad. Detailed Implementation

[0032] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0033] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0034] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0035] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0036] See Figures 1 to 8 As shown in the figure, this application discloses a self-locking device for a drive motor. The drive motor 1 includes a motor body and a shaft 100. The shaft 100 of the drive motor 1 has a power output end 101 and a tail end 102 opposite to the output end 101. The tail end 102 of the drive motor 1 shaft 100 extends axially out of the motor body. In this embodiment, the self-locking device includes a cover 2, a friction component 3, an elastic element 4, and a driving component. The cover 2 is hollow and fixedly connected to the tail end of the drive motor 1 by fasteners. The friction component 3 is disposed inside the cover 2 and sleeved on the tail end 102 opposite to the output end 101 of the drive motor 1 shaft 100. It is easy to understand that the tail end 102 of the drive motor 1 shaft 100 at least partially extends into the cover 2. That is, in this embodiment, the self-locking device is integrated into the tail end of the drive motor 1. This reduces the overall size of the drive motor 1 with the self-locking device without changing its structure, thus expanding its application range.

[0037] Further in this embodiment, see Figure 2 , Figure 5 and Figure 6 As shown, the friction assembly 3 includes multiple static friction plates 300 and multiple dynamic friction plates 301, which are arranged alternately in sequence along the axial direction of the drive motor 1 shaft 100. The static friction plates 300 are circumferentially confined within the cover 2, while the dynamic friction plates 301 rotate synchronously with the drive motor 1 shaft 100 and have a sliding clearance along the axial direction. That is, except for the dynamic friction plates 301 located at the outermost or innermost side of the tail end 102 of the shaft 100... Each moving friction plate 301 has a stationary friction plate 300 arranged on both sides. Alternatively, except for the stationary friction plate 300 located on the outermost or innermost side of the tail end 102 of the rotating shaft 100, each stationary friction plate 300 has a moving friction plate 301 arranged on both sides. The stationary friction plates 300 and the moving friction plates 301 are arranged alternately and stacked. Each adjacent stationary friction plate 300 and the moving friction plate 301 can come into contact to generate friction, thereby increasing the contact area between the friction plates, improving the friction, and thus improving the self-locking ability.

[0038] For example, see Figure 2 , Figure 5 and Figure 6As shown, the static friction plate 300 and the dynamic friction plate 301 are arranged alternately in a axial sequence. The outer peripheral wall of the static friction plate 300 is quadrilateral, and the fit between the outer peripheral wall of the static friction plate 300 and the inner wall of the cover 2 forms a circumferential limiting structure that restricts the circumferential rotation of the static friction plate 300, thus allowing the static friction plate 300 to move only along the axial direction and preventing it from rotating circumferentially with the rotating shaft 100. The dynamic friction plate 301, on the other hand, is disc-shaped. The moving friction plate 301 is axially slidably fitted onto the tail end 102 of the rotating shaft 100 and rotates synchronously with the rotating shaft 100. Specifically, the tail end 102 of the rotating shaft 100 is provided with a flat surface 103 along the axial direction, and the inner wall of the mounting hole 304 of the moving friction plate 301 is provided with a flat cut portion that matches the shape of the flat surface 103 of the tail end 102 of the rotating shaft 100, so that the moving friction plate 301 is circumferentially limited on the rotating shaft 100 and can slide along the axial direction of the rotating shaft 100. Based on this, when axial pressure is applied to the friction assembly 3, the stationary friction plate 300 and the moving friction plate 301 move axially and can press against each other, generating friction between the mating surfaces of the stationary friction plate 300 and the moving friction plate 301, thereby stopping the moving friction plate 301 from rotating and self-locking the rotating shaft 100 of the drive motor 1. It is understandable that when the axial force applied to the friction assembly 3 disappears, the axial force that causes the static friction plate 300 and the moving friction plate 301 to press against each other disappears, the moving friction plate 301 can rotate relative to the static friction plate 300 with the rotating shaft 100, and the self-locking of the drive motor 1 is released.

[0039] In this embodiment, an elastic element 4 is connected inside the cover 2. The elastic element 4 is used to apply axial pressure to the friction assembly 3 so that the static friction plate 300 and the dynamic friction plate 301 always have a tendency to press against each other. The driving element is driven to connect with the elastic element 4 and is used to drive the elastic element 4 or apply axial pressure to the elastic element 4 so that the elastic element 4 is in a compressed state or a released state. In the compressed state, the static friction plate 300 and the dynamic friction plate 301 are separated from each other so that the driving motor 1 is in a non-locking state. The compressed state is that the driving element drives the elastic element 4 to compress away from the friction assembly 3. In the released state, the elastic element 4 recovers its elastic deformation so that the static friction plate 300 and the dynamic friction plate 301 press against each other so that the driving motor 1 is in a self-locking state.

[0040] In the above embodiments, see Figure 2 , Figure 3 and Figure 4As shown, under the action of the elastic element 4, the static friction plate 300 and the dynamic friction plate 301 can always be pressed against each other to generate friction force and make the shaft 100 of the drive motor 1 self-lock. When the self-lock is released, it is only necessary to compress the elastic element 4 in the direction away from the friction assembly 3 so that the elastic element 4 is in a compressed state. At the same time, the force applied by the elastic element 4 to the friction assembly 3 disappears, and the elastic force applied by the elastic element 4 to the friction assembly 3 can be released, so that there is no axial pressure between the dynamic friction plate 301 and the static friction plate 300, and the self-lock of the shaft 100 of the drive motor 1 is released. The friction component 3 of the self-locking device uses multiple static friction plates 300 and multiple dynamic friction plates 301 arranged alternately along the axial direction. During self-locking, each dynamic friction plate 301 is pressed against its adjacent static friction plate 300 to generate friction. Therefore, the contact area between the dynamic friction plate 301 and the static friction plate 300 of the self-locking device for the drive motor is large, and a large friction force can be generated during self-locking, thus making its self-locking ability strong and its self-locking stability high. Even if one friction plate is worn and fails, it will not affect the friction force between other friction plates. Therefore, the self-locking device is not easy to fail and has a long service life.

[0041] It is understandable that if the axial force applied to the friction assembly 3 is unbalanced or shifts, it may cause the moving friction plate 301 and the stationary friction plate 300 on one side of the friction assembly 3 to press together and generate friction, while the moving friction plate 301 and the stationary friction plate 300 on the other side will relatively open, thus weakening the self-locking effect. In this embodiment, see... Figure 2 , Figure 3 and Figure 4 As shown, a pressure plate 5 is provided between the friction assembly 3 and the elastic member 4. The elastic member 4 abuts against the pressure plate 5, which is used to press the friction assembly 3 axially with the pressure plate 5. A driving member is driven to the pressure plate 5, which is used to drive the pressure plate 5 to move axially away from the friction assembly 3 to compress the elastic member 4. The setting of the pressure plate 5 makes the compressive force between the moving friction plate 301 and the stationary friction plate 300 of the friction assembly 3 balanced, and effectively avoids the defect of weakened self-locking effect caused by the displacement of the moving friction plate 301 and / or the stationary friction plate 300.

[0042] In the above embodiments, the driving component can be an electromagnetic switch, that is, the push rod or armature of the electromagnetic switch drives the elastic element 4 to compress or drives the elastic element 4 to compress via the driving pressure plate 5; the driving component can also be a small electric push rod, a micro linear motor, etc., using the axial force generated by it to drive the elastic element 4 to compress or drive the elastic element 4 to compress via the driving pressure plate 5. In this embodiment, in order to further reduce the size of the self-locking device and make the size of the drive motor 1 with the self-locking device smaller, the driving component is integrated into the cover 2. Specifically, see Figure 2 , Figure 3 and Figure 4As shown, the driving component is an electromagnetic coil 6 connected inside the cover 2. The electromagnetic coil 6 is located on the side of the pressure plate 5 away from the friction assembly 3. The pressure plate 5 is made of a magnetically conductive material. When the electromagnetic coil 6 is energized, it magnetically attracts the pressure plate 5 to compress the elastic element 4. When the electromagnetic coil 6 is de-energized, the elastic element 4 is released, causing the pressure plate 5 to press against the friction assembly 3, thus pressing the static friction plate 300 and the dynamic friction plate 301 against each other. That is, in this embodiment, the electromagnetic coil 6 is integrated inside the cover 2. The electromagnetic force generated by the energized electromagnetic coil 6 magnetically attracts the pressure plate 5, thereby compressing the elastic element 4. When the electromagnetic coil 6 is de-energized, the electromagnetic force attracting the pressure plate 5 disappears, and the pressure plate 5 is pressed against the friction assembly 3 under the elastic force of the elastic element 4.

[0043] Further in the above embodiment, when the drive motor 1 is working, the electromagnetic coil 6 is energized to generate electromagnetic force to magnetically attract the pressure plate 5, causing the pressure plate 5 to move away from the friction assembly 3 to compress the elastic element 4. At the same time, the pressure plate 5 disengages from the friction assembly 3, the force applied to the friction assembly 3 disappears, and the elastic force applied to the friction assembly 3 by the elastic element 4 is released, so that there is no axial pressure between the moving friction plate 301 and the stationary friction plate 300. The self-locking of the drive motor 1 shaft 100 is released, and the drive motor 1 shaft 100 rotates. When the drive motor 1 stops working, the electromagnetic coil 6 is de-energized and the electromagnetic force disappears. Under the elastic force of the elastic element 4, the pressure plate 5 presses the friction assembly 3 axially, so that the stationary friction plate 300 and the moving friction plate 301 are pressed together, and the motor shaft 100 self-locks.

[0044] In this embodiment, the elastic element 4 is a columnar spring. In other embodiments, the elastic element 4 may also be a tower spring or other elastic component with axial elastic force and compressible elastic deformation.

[0045] Furthermore, in this embodiment, the materials of the static friction plate 300 and the dynamic friction plate 301 are not limited. They can be metal friction plates or friction discs, or friction plates made of plastic or rubber. Alternatively, the dynamic friction plate 301 can be made of metal, while the static friction plate 300 can be made of plastic, rubber, or other materials.

[0046] To further improve the friction between the static friction plate 300 and the dynamic friction plate 301 of the friction assembly 3, thus enhancing the self-locking capability of the self-locking device, see [link to relevant documentation]. Figure 5 , Figure 6 , Figure 7 and Figure 8As shown, the two end faces of the stationary friction plate 300 are respectively provided with a plurality of radial grooves 302 along the circumference, and a friction zone is formed between two adjacent radial grooves 302 that contacts the moving friction plate 301. This arrangement can increase the friction between the moving friction plate 301 and the stationary friction plate 300, thereby improving the self-locking capability of the self-locking device. In addition, the radial grooves 302 can store a portion of lubricating oil to reduce the wear of the friction plates, extend the service life of the friction plates, and reduce the noise when the friction plates contact braking.

[0047] Furthermore, in the above embodiment, the inner wall of the central hole 303 of the static friction plate 300 is configured to not contact the tail end 102 of the drive motor 1 shaft 100. That is, the static friction plate 300 is coaxially arranged with the drive motor 1 shaft 100, and the diameter of the central hole 303 of the static friction plate 300 is much larger than the outer diameter of the drive motor 1 shaft 100, so that there is an annular gap between the inner wall of the central hole 303 of the static friction plate 300 and the outer peripheral wall of the drive motor 1 shaft 100. In this way, when the drive motor 1 shaft 100 rotates, the shaft 100 and the static friction plate 300 do not contact each other, preventing damage caused by high-speed friction between the static friction plate 300 and the shaft 100, and extending its service life.

[0048] In this embodiment, see Figure 2 , Figure 3 and Figure 4 As shown, the electromagnetic coil 6, elastic element 4, and pressure plate 5 are positioned on the side of the cover 2 away from the drive motor 1, relative to the friction assembly 3. This arrangement, compared to related technologies where the electromagnetic coil 6, elastic element 4, and pressure plate 5 are positioned between the friction assembly 3 and the drive motor 1, allows for an increase in the number of turns and length of the electromagnetic coil 6, resulting in a stronger electromagnetic force. This allows for a faster response and unlocking when the drive motor 1 releases its self-lock, avoiding delays in the release of the self-lock of the drive motor 1's shaft 100, which could affect the normal operation of the drive motor 1. Furthermore, this arrangement provides ample installation space for the electromagnetic coil 6, elastic element 4, and pressure plate 5, facilitating their assembly.

[0049] Further in this embodiment, see Figure 2 , Figure 3 and Figure 4As shown, a hollow support base 202 is provided axially at the center of the cover 2. The support base 202 is integrally formed with the cover 2, and the electromagnetic coil 6 is wound around the support base 202. The elastic element 4 is disposed in the inner hole of the support base 202, with one end of the elastic element 4 abutting against the inner wall of the inner hole of the support base 202 and the other end abutting against the pressure plate 5, so that the pressure plate 5 always has the tendency to press the friction assembly 3. In this way, the support base 202 not only serves to support the electromagnetic coil 6, but also to fix the elastic element 4. In addition, the support base 202 is located at the center of the cover 2, so that the contact point between the elastic element 4 in the inner hole of the support base 202 and the pressure plate 5 is located at the center of the pressure plate 5, thereby balancing the force on the pressure plate 5.

[0050] It is easy to understand that when the electromagnetic coil 6 is energized, it generates electromagnetic force, which magnetically attracts the pressure plate 5. This causes the pressure plate 5 to quickly compress the elastic element 4 away from the friction assembly 3 and abut against the outer end face of the support base 202. This generates a large impact force, thus producing noise. Therefore, in this embodiment, a protruding soft buffer pad 7 is provided on the free end face of the support base 202. When the pressure plate 5 moves away from the friction assembly 3 when the electromagnetic coil 6 is energized, it abuts against the buffer pad 7. Specifically, see... Figure 3 and Figure 4 As shown, an annular groove is provided on the free end face of the support 202, and the soft buffer pad 7 is annular. The soft buffer pad 7 is tightly fitted in the annular groove. When the pressure plate 5 abuts against the soft buffer pad 7, the soft buffer pad 7 can absorb the impact force of the pressure plate 5, so that when the pressure plate 5 abuts against the free end face of the support 202, the noise is low and the quietness effect is good.

[0051] In some embodiments, see Figure 1 , Figure 3 As shown, the cover 2 includes a first housing 200 connected to the tail of the drive motor 1 and a second housing 201 connected to the first housing 200. The friction assembly 3 and the pressure plate 5 are sequentially arranged in the first housing 200, and the electromagnetic coil 6 and the elastic element 4 are arranged in the second housing 201. This arrangement facilitates the installation of the self-locking device, making the installation unrestricted by the installation space, and the operation is simple and convenient.

[0052] Furthermore, in this embodiment, the second housing 201 is provided with a limiting step 203 at one end near the first housing 200 for the pressure plate 5 to abut against. This limiting step 203 limits the stroke or range of motion of the pressure plate 5, thereby making the movement of the pressure plate 5 more stable and smooth. The distance from the free end face of the support 202 to the pressure plate 5 is slightly less than the distance from the limiting step 203 to the pressure plate 5. This arrangement allows the pressure plate 5 to first abut against the soft buffer pad 7 on the free end face of the support 202 when moving away from the friction assembly 3 to compress the elastic element 4, thereby reducing impact force and noise. Even if the pressure plate 5 shifts, the limiting step 203 provides some support to the edge of the pressure plate 5, preventing excessive shifting or tilting of the pressure plate 5.

[0053] Another embodiment of this application discloses a self-locking drive motor, see [link]. Figure 1 As shown, the self-locking drive motor includes a self-locking device for a drive motor as described in any of the above embodiments. Because the self-locking drive motor employs the self-locking device of the above embodiments, it possesses strong self-locking capability, and the self-locking device is not prone to failure and exhibits high self-locking stability.

[0054] In the description of the embodiments of this application, it should be noted that the terms "inner" and "outer" and other terms indicating direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0055] In the description of this application, the references to terms such as "an embodiment," "some embodiments," "in this embodiment," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0056] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A self-locking device for a drive motor, characterized in that: include The cover is connected to the tail of the drive motor; A friction assembly is disposed within the cover body and sleeved on the tail end opposite to the output end of the drive motor shaft. The friction assembly includes multiple static friction plates and multiple dynamic friction plates, which are arranged alternately in sequence along the axial direction of the drive motor shaft. The static friction plates are circumferentially limited within the cover body, and the dynamic friction plates rotate synchronously with the drive motor shaft, and the dynamic friction plates have a sliding gap along the axial direction. An elastic element, connected to the cover body, is used to ensure that the static friction plate and the dynamic friction plate always have a tendency to press against each other. A driving component, drivenly connected to the elastic element, is used to put the elastic element into a compressed state or a released state. In the compressed state, the static friction plate and the dynamic friction plate are separated from each other, so that the driving motor is in a non-self-locking state; in the released state, the static friction plate and the dynamic friction plate are pressed together, so that the driving motor is in a self-locking state.

2. The self-locking device for a drive motor according to claim 1, characterized in that: A pressure plate is provided between the friction assembly and the elastic element. The elastic element abuts against the pressure plate, which is used to press the friction assembly axially. The driving member is driven to the pressure plate, which is used to drive the pressure plate to move axially away from the friction assembly to compress the elastic element.

3. The self-locking device for a drive motor according to claim 2, characterized in that: The driving component is an electromagnetic coil connected to the cover body. The electromagnetic coil is located on the side of the pressure plate away from the friction assembly. The pressure plate is made of magnetically conductive material. When the electromagnetic coil is energized, it magnetically attracts the pressure plate to compress the elastic element. When the electromagnetic coil is de-energized, the elastic element is released so that the pressure plate presses the friction assembly tightly, so that the static friction plate and the dynamic friction plate press against each other.

4. The self-locking device for a drive motor according to claim 3, characterized in that: The electromagnetic coil, the elastic element, and the pressure plate are disposed on the side of the cover away from the drive motor, relative to the friction assembly.

5. The self-locking device for a drive motor according to claim 3, characterized in that: The cover has a hollow support seat along the axial direction at its center. The electromagnetic coil is wound around the support seat. The elastic element is disposed in the inner hole of the support seat. One end of the elastic element abuts against the inner wall of the inner hole of the support seat, and the other end abuts against the pressure plate, so that the pressure plate always has a tendency to press the friction assembly.

6. The self-locking device for a drive motor according to claim 5, characterized in that: The free end face of the support is provided with a protruding soft buffer pad, and the pressure plate abuts against the buffer pad when the electromagnetic coil is energized and moves away from the friction assembly.

7. The self-locking device for a drive motor according to claim 6, characterized in that: The cover includes a first housing connected to the tail of the drive motor and a second housing connected to the first housing. The friction assembly and the pressure plate are sequentially arranged inside the first housing. The second housing has a limiting step at one end near the first housing for the pressure plate to abut against it.

8. The self-locking device for a drive motor according to claim 7, characterized in that: The distance from the free end face of the support to the pressure plate is less than the distance from the limiting step to the pressure plate.

9. The self-locking device for a drive motor according to claim 1, characterized in that: The two end faces of the static friction plate are respectively provided with a plurality of radial grooves along the circumference, and a friction zone that contacts the dynamic friction plate is formed between two adjacent radial grooves; the inner wall of the central hole of the static friction plate does not contact the tail end of the drive motor shaft.

10. A self-locking drive motor, characterized in that: Includes the self-locking device for drive motors as described in any one of claims 1 to 9.

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