CN214999143U

CN214999143U - Linear actuator and lifting platform

Info

Publication number: CN214999143U
Application number: CN202121068704.4U
Authority: CN
Inventors: 韩益南; 陈理钢
Original assignee: Zhejiang Jiecang Linear Motion Technology Co Ltd
Current assignee: Zhejiang Jiecang Linear Motion Technology Co Ltd
Priority date: 2021-05-18
Filing date: 2021-05-18
Publication date: 2021-12-03
Anticipated expiration: 2031-05-18

Abstract

The utility model discloses a linear actuator and lift platform belongs to the linear actuator field, and self-locking mechanism can provide stable braking force in order to realize two-way auto-lock, and long service life, the utility model discloses a linear actuator, including driver, drive disk assembly and stand, drive disk assembly includes worm wheel and worm, the stand includes the lead screw, the wheel hub of worm wheel the worm with at least one in the lead screw is equipped with self-locking mechanism, self-locking mechanism includes the friction seat and the elastic sleeve ring, friction seat suit on linear actuator's the axis body and with axis body interference fit to on applying the axis body with the braking force, the elastic sleeve ring is installed just have the effort that is used in the radial direction of axis body on the friction seat, be used for keeping the interference fit of friction seat and axis body to realize the two-way auto-lock of axis body to the axis body.

Description

Linear actuator and lifting platform

Technical Field

The utility model relates to a linear actuator field especially relates to linear actuator and lift platform.

Background

The linear actuator can output power, and can be used in some furniture used in daily life, such as tables and chairs capable of lifting, or some equipment, such as a lifting workbench. The linear actuator can output power to control the load to move in a linear direction, when the load moves to a required position, the linear actuator can stop outputting power and keep the position of the load unchanged, in order to ensure accurate control of the position of the load, the linear actuator needs to ensure that the linear actuator can quickly stop generating internal power, and in order to ensure that the position of the load does not change when the linear actuator stops, the linear actuator needs to overcome the influence of acting force. In the prior art, a brake element is disclosed, which is formed by integral molding and is sleeved on a driving shaft of a motor in an interference fit manner to provide braking force, but after a long time of use, the braking element is worn to cause the reduction of the braking force.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem that solve lies in overcoming prior art not enough and proposing linear actuator, self-locking mechanism can provide stable braking force in order to realize two-way auto-lock, and long service life.

In order to solve the technical problem, the utility model adopts the following technical scheme:

the linear actuator comprises a driver, a transmission part and an upright post, wherein the transmission part comprises a worm wheel and a worm, the upright post comprises a screw rod, at least one of a hub of the worm wheel, the worm and the screw rod is provided with a self-locking mechanism, the self-locking mechanism comprises a friction seat and an elastic lantern ring, the friction seat is sleeved on a shaft body of the linear actuator and is in interference fit with the shaft body so as to apply braking force to the shaft body, and the elastic lantern ring is installed on the friction seat and has acting force acting in the radial direction of the shaft body and is used for keeping the interference fit of the friction seat and the shaft body so as to realize bidirectional self-locking of the shaft body.

On the basis of the scheme, the friction seat comprises a friction base body and a circular opening penetrating through the friction base body, and the surface of an inner ring of the circular opening is abutted to the shaft body.

On the basis of the scheme, the end part of the friction base body is provided with a first bulge part arranged along the circumferential edge of the circular opening, and the inner ring of the first bulge part is connected with the inner ring of the circular opening.

On the basis of the scheme, the elastic lantern ring is installed on the periphery of the first protruding portion and is in interference fit with the first protruding portion.

On the basis of the scheme, the circumferential surface of the first protruding part is provided with a surrounding edge protruding outwards, and the elastic lantern ring is located between the surrounding edge and the friction base body.

On the basis of the scheme, the end part of the friction base body is also provided with a second protruding part arranged along the periphery of the friction base body, and the first protruding part and the second protruding part are arranged on the same side.

On the basis of the scheme, the friction base body, the first protruding portion and the second protruding portion are integrally formed rubber pieces.

On the basis of the scheme, the self-locking mechanism further comprises a framework wrapped by the friction seat.

On the basis of the scheme, the elastic lantern ring is a plastic part, a ceramic part or a metal part, and the inner ring of the elastic lantern ring is closed on the circumference.

On the basis of the scheme, the driver further comprises a motor and an end cover, the worm is a driving shaft of the motor, and the friction seat is sleeved on the worm and is in interference fit with the end cover.

On the basis of the scheme, the transmission part further comprises a worm wheel mounting seat, and the friction seat is sleeved on the hub of the worm wheel and is in interference fit with the worm wheel mounting seat.

On the basis of the scheme, the upright column further comprises a sleeve and a mounting seat arranged in the sleeve, the screw rod is arranged in the sleeve and is rotationally connected with the mounting seat, and the friction seat is sleeved on the screw rod and is in interference fit with the mounting seat or the sleeve.

A lifting platform comprising the linear actuator described above.

The utility model has the advantages that:

the utility model discloses a linear actuator, the worm transmits the power of driver to the worm wheel, through the cooperation of worm wheel and lead screw, the drive lead screw rotates in order to control the stand motion, self-locking mechanism passes through the friction seat suit on the axis body that needs locking part (need locking part can be the worm wheel, worm and lead screw, the wheel hub of worm wheel, the body of rod of worm and lead screw), the friction seat is through the mode with axis body interference fit, produce the brake force that acts on the axis body, brake force is the frictional force between friction seat and the axis body promptly, when the axis body rotates, be sliding friction between the two, the axis body is overcome the frictional force and is rotated, because the driver that has the power that can produce in the linear actuator, under the drive power effect of driver, the axis body can easily overcome the influence of frictional force to its pivoted;

the elastic lantern ring always has acting force acting on the shaft body in the radial direction, and the shape of the spring lantern ring is annular, so that the friction force between the friction seat and the shaft body is unchanged no matter the shaft body rotates forwards or backwards, and the shaft body can be subjected to bidirectional self-locking;

when the linear actuator is in an operating state (the shaft body rotates in a positive direction), the shaft body rotates relative to the friction seat, sliding friction exists between the shaft body and the friction seat, when the linear actuator needs to stop, the power of the driver stops, but the worm can continue to rotate by means of inertia to drive the worm wheel and the screw rod, sliding friction still exists between the shaft body and the friction seat, and the friction force can quickly stop the rotation of the shaft body and keep a static state;

when the linear actuator is in a static state, if the upright post is subjected to an external acting force, a part of the acting force may cause the shaft body to have a rotation trend (i.e., the acting force acting in the tangential direction of the shaft body occurs, so that the shaft body rotates in a reverse direction), and the upright post may retract, at the moment, a static friction force exists between the shaft body and the friction seat, and the acting force cannot overcome the static friction force of the shaft body and the friction seat to drive the shaft body to rotate, so that the self-locking mechanism can lock the linear actuator to keep the static state of the linear actuator;

after long-time use, wearing and tearing can appear in the friction seat, lead to the magnitude of interference between friction seat and the axis body to reduce and make frictional force reduce, and the elastic sleeve ring can produce the effort of acting on the axis body, make and keep interference fit between friction seat and the axis body, even wearing and tearing appear in the friction seat, the magnitude of interference between friction seat and the axis body can be guaranteed under the effect of the elastic sleeve ring, thereby can not reduce the frictional force between the two, make self-locking mechanism's life-span prolong greatly, the elastic sleeve ring does not with axis body direct contact, consequently also can not produce wearing and tearing, can produce stable effort, in order to guarantee self-locking mechanism's brake performance.

Furthermore, the friction seat comprises a friction base body and a circular opening penetrating through the friction base body, the surface of an inner ring of the circular opening is abutted against the shaft body, when the friction seat is installed on the shaft body of the linear actuator, the shaft body penetrates through the circular opening in the friction base body and is abutted against the surface of the inner ring of the circular opening, so that friction force can be generated between the inner ring of the circular opening and the shaft body, the shape of the circular opening is matched with that of the shaft body, the circular opening and the shaft body are in full contact, and therefore the abrasion of the friction seat can be reduced; if the opening is square, the friction force between the friction seat and the shaft body is not changed, the total amount of the reaction force acting on the friction seat is also not changed, but the contact area between the friction seat and the shaft body is reduced, so that the abrasion is serious.

Furthermore, the end part of the friction base body is provided with a first protruding part arranged along the periphery of the circular opening, the inner ring of the first protruding part is connected with the inner ring of the circular opening, the contact area between the friction seat and the shaft body can be increased after the first protruding part is arranged, the abrasion degree of the friction seat is reduced, and the service life is prolonged.

Furthermore, the elastic sleeve ring is installed in the periphery of the first boss and in interference fit with the first boss, the elastic sleeve ring exerts an acting force on the shaft body in an interference fit mode with the first boss, the interference fit between the friction seat and the shaft body can be kept, the friction force generated between the friction seat and the shaft body can be increased, the self-locking and braking effects are improved, the elastic sleeve ring is not arranged inside the friction seat but directly sleeved outside the first boss, the installation is convenient, the strength of the elastic sleeve ring is high, the elastic sleeve ring is not easy to damage, when the abrasion degree of the friction seat is large, the elastic sleeve ring can be taken down and sleeved on another friction seat, and therefore the cost can be saved.

Furthermore, the circumferential surface of first bellying is equipped with outside convex surrounding edge, the elastic sleeve ring is located the surrounding edge with between the friction base member, convex surrounding edge can carry on spacingly to the elastic sleeve ring, restricts it between surrounding edge and friction base member, so at the course of the work, if the non-axle axial direction's effort is used in the elastic sleeve ring, the elastic sleeve ring is difficult to separate with the friction seat, overall structure is stable.

Furthermore, the end part of the friction base body is also provided with a second protruding part arranged along the periphery of the friction base body, the first protruding part and the second protruding part are arranged on the same side, after the second protruding part is arranged, the thickness of the friction seat can be increased, and when the self-locking mechanism is installed in the linear actuator, the rotation of the self-locking mechanism can be conveniently limited.

Further, the friction base member first bellying with the second bellying is integrated into one piece's rubber spare, mode through integrated into one piece, the manufacturing degree of difficulty is low, the rubber spare has not little coefficient of friction, can and the axis body between produce considerable frictional force, and the rubber spare has certain deformability, when rubber spare and axis body interference fit, it has taken place deformation to mean that the rubber spare has taken place, the effort of acting on the axis body has, thereby can and the axis body between produce frictional force, after the elastic lantern ring has been installed, the numerical value of effort and the deformation degree of rubber spare have been increased, after the rubber spare wearing and tearing, the rubber spare still can be in deformation state and with axis body in close contact with under the effect of the elastic lantern ring, thereby can guarantee the auto-lock ability.

Furthermore, the self-locking mechanism also comprises a framework wrapped by the friction seat. The framework is not easy to deform, and under the action of the framework, the friction force between the friction seat and a component used for installing and fixing the self-locking mechanism in the linear actuator can be increased, so that the rotation of the friction seat relative to the shaft body can be better limited.

Furthermore, the elastic lantern ring is a plastic part, a ceramic part or a metal part, the inner ring of the elastic lantern ring is closed on the circumference of the elastic lantern ring, the continuous elastic lantern ring can apply uniform acting force on the periphery of the driving shaft, the local abrasion of the friction seat is avoided to be serious, the service life of the self-locking mechanism can be prolonged, the plastic, the ceramic and the metal materials have various advantages, and the manufactured friction seat has high strength so as to ensure that the friction seat can be stable.

The utility model also discloses a lift platform has adopted foretell linear actuator, and lift platform passes through the control of linear actuator and goes up and down, can accomplish that lift platform in time stops, the condition that can not appear backing back in the use, and convenience of customers uses.

These features and advantages of the present invention will be disclosed in more detail in the following detailed description and the accompanying drawings.

Drawings

The invention will be further explained with reference to the drawings:

fig. 1 is a schematic structural diagram of a linear actuator according to an embodiment of the present invention;

fig. 2 is an exploded view of the one-way self-locking mechanism in the embodiment of the present invention;

fig. 3 is a sectional view of the one-way self-locking mechanism in the embodiment of the present invention;

fig. 4 is a schematic structural diagram of a transmission component in an embodiment of the present invention;

FIG. 5 is a schematic view of the connection between the worm and the one-way self-locking mechanism in the embodiment of the present invention;

FIG. 6 is a schematic view of the connection between the worm wheel and the one-way self-locking mechanism in the embodiment of the present invention;

fig. 7 is an exploded view of the column in the embodiment of the present invention;

fig. 8 is an enlarged schematic view at a in fig. 7.

Reference numerals:

driver 100, housing 110, end cap 120, mounting slot 130;

a transmission part 200, a worm wheel 210, a hub 211, a worm 220, a worm wheel mounting seat 230;

upright 300, screw rod 310, sleeve 320, sleeve mounting seat 330, inner tube 340 and nut 350;

the friction seat 400, the friction base 401, the circular opening 402, the first boss 403, the surrounding edge 404, the second boss 405 and the elastic collar 410.

Detailed Description

The technical solutions of the embodiments of the present invention are explained and explained below with reference to the drawings of the embodiments of the present invention, but the embodiments described below are only preferred embodiments of the present invention, and not all embodiments. Based on the embodiments in the embodiment, other embodiments obtained by those skilled in the art without any creative work belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and to simplify the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "a plurality" means two or more unless explicitly defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Referring to fig. 1 to 3, the embodiment of the present invention discloses a linear actuator, including driver 100, transmission part 200 and stand 300, transmission part 200 includes worm wheel 210 and worm 220, stand 300 includes lead screw 310, at least one among wheel hub 211 of worm wheel 210, worm 220 and lead screw 310 is equipped with self-locking mechanism, self-locking mechanism includes friction seat 400 and elastic sleeve ring 410, friction seat 400 suit is on linear actuator's the axis body and with axis body interference fit, in order to exert the axis body with the brake force on, elastic sleeve ring 410 installs on friction seat 400 and has the effort that is used in the radial direction of axis body, be used for keeping friction seat 400 and the interference fit of axis body, in order to realize the two-way auto-lock to the axis body.

The linear actuator generates power through the driver 100, the worm 220 transmits the power of the driver 100 to the worm gear 210, the worm wheel 210 is matched with the screw rod 310 to drive the screw rod 310 to rotate so as to control the upright post 300 to move, the self-locking mechanism is sleeved on a shaft body needing to be locked through the friction seat 400 (the part needing to be locked can be the worm wheel 210, the worm 220 and the screw rod 310, and the hub 211 of the worm wheel 210, the worm 220 and the rod body of the screw rod 310), the friction seat 400 generates braking force acting on the shaft body in a manner of interference fit with the shaft body, the braking force is the friction force between the friction seat 400 and the shaft body, when the shaft body rotates, sliding friction exists between the shaft body and the shaft body, the shaft body rotates against the friction force, and because the linear actuator is internally provided with the driver 100 capable of generating power, under the action of the driving force of the driver 100, the shaft body can easily overcome the influence of friction force on the rotation of the shaft body;

the elastic collar 410 always has an acting force acting on the shaft body in the radial direction, and the shape of the spring collar is annular, so that the friction force between the friction seat 400 and the shaft body is unchanged no matter whether the shaft body rotates forwards or backwards, and the shaft body can be subjected to bidirectional self-locking;

when the linear actuator is in an operating state (the shaft body rotates in a forward direction), the shaft body rotates relative to the friction seat 400, sliding friction exists between the shaft body and the friction seat 400, when the linear actuator needs to stop, the power of the driver 100 stops, but the worm 220 can continue to rotate by means of inertia to drive the worm wheel 210 and the screw rod 310, sliding friction still exists between the shaft body and the friction seat 400, and the friction force can quickly stop the rotation of the shaft body and keep a static state;

when the linear actuator is in a static state, if the upright post 300 is subjected to an external acting force, a part of the acting force may cause the shaft body to have a rotation tendency (i.e., an acting force acting in a tangential direction of the shaft body occurs, and the shaft body rotates in a reverse direction), which may cause the upright post 300 to retract, and at this time, a static friction force exists between the shaft body and the friction seat 400, and the acting force cannot overcome the static friction force of the shaft body and the friction seat to drive the shaft body to rotate, so that the self-locking mechanism can lock the linear actuator to maintain the static state of the linear actuator;

after long-time use, the friction seat 400 can be worn, the interference between the friction seat 400 and the shaft body is reduced, the friction force is reduced, the elastic sleeve ring 410 can generate acting force acting on the shaft body, the friction seat 400 and the shaft body are in interference fit, even if the friction seat 400 is worn, the interference between the friction seat 400 and the shaft body can be guaranteed under the action of the elastic sleeve ring 410, the friction force between the friction seat 400 and the shaft body cannot be reduced, the service life of the self-locking mechanism is greatly prolonged, the elastic sleeve ring 410 is not in direct contact with the shaft body, abrasion cannot be generated, stable acting force can be generated, and the braking performance of the self-locking mechanism can be guaranteed.

The friction seat 400 is a rubber member, the rubber member has a small friction coefficient, and can generate considerable friction force with the shaft body, and the rubber member has a certain deformation capacity, when the rubber member is in interference fit with the shaft body, it means that the rubber member has been deformed, and has an acting force acting on the shaft body, so that friction force can be generated between the rubber member and the shaft body, but the interference fit between the rubber member and the shaft body is not enough to generate enough friction force to perform self-locking or braking on the linear actuator, so that the acting force acting on the shaft body is increased by providing the elastic collar 410, so as to increase the friction force and the deformation degree of the rubber member, when the rubber member is worn, the elastic collar 410 can make the friction seat 400 maintain a deformation state by the acting force acting on the friction seat 400, so as to maintain the tight contact with the shaft body, and maintain the self-locking capacity of the self-locking device, the friction seat 400 can prevent the elastic collar 410 from directly contacting the shaft body, and prevent a large amount of heat from being generated between the two, which affects the performance of the linear actuator. The elastic sleeve ring 410 is not deformed and not easy to damage in the operation process, so that the elastic sleeve ring can be recycled and used repeatedly, and the overall cost is low. The elastic lantern ring 410 is a plastic piece, a ceramic piece or a metal piece, preferably spring steel, the inner ring of the elastic lantern ring 410 is closed on the circumference, the continuous elastic lantern ring 410 can apply uniform acting force on the periphery of the driving shaft, the local abrasion of the friction seat 400 is avoided to be serious, the service life of the self-locking mechanism can be prolonged, the plastic, the ceramic and the metal materials have various advantages, and the manufactured friction seat 400 has high strength so as to ensure that the friction seat can generate stable acting force.

The friction seat 400 comprises a friction base 401 and a circular opening 402 penetrating through the friction base 401, the friction base 401 is sleeved on the shaft body through the circular opening 402, the surface of an inner ring of the circular opening 402 is abutted against the shaft body, so that the inner ring of the circular opening 402 can generate friction force with the shaft body, the shape of the circular opening 402 is matched with the shaft body, the inner ring of the circular opening 402 is not provided with a notch in the circumferential direction and can be in full contact with the shaft body, the abrasion of the friction seat 400 can be reduced, and the friction seat 400 is prevented from being partially abraded.

If the opening provided in the friction base 401 is square or has another shape, the opening cannot be sufficiently contacted with the shaft, the contact area of the whole is small, and although the friction force is not reduced, the reaction force acting on the friction base 400 is generated by the friction force, and the force-receiving area on the friction base 400 is smaller without changing the total amount of the reaction force, so that the friction base 400 is more easily worn.

Referring to fig. 2 and 3, in another embodiment of the present invention, based on the above-described scheme, a specific structure of the self-locking mechanism is explained,

the end of the friction base 401 is provided with a first protrusion 403 arranged along the circumference of the circular opening 402, the inner ring of the first protrusion 403 is connected with the inner ring of the circular opening 402, and the first protrusion 403 can further increase the contact area between the friction seat 400 and the shaft body, reduce the wear degree of the friction seat 400, and improve the service life.

The elastic sleeve ring 410 is sleeved on the periphery of the first protruding portion 403 and is in interference fit with the first protruding portion 403, the elastic sleeve ring 410 applies acting force to the shaft body in an interference fit mode with the first protruding portion 403, friction force between the friction seat 400 and the shaft body is improved, self-locking and braking effects are enhanced, the elastic sleeve ring 410 is not arranged inside the friction seat 400 and is directly sleeved outside the first protruding portion 403, the installation is convenient, the strength of the elastic sleeve ring 410 is high, the friction sleeve ring is not prone to damage, when the abrasion degree of the friction seat 400 is large, the elastic sleeve ring 410 can be taken down and sleeved on another friction seat 400, cost can be saved, the installation is convenient, a user can purchase a plurality of friction sleeve prices when purchasing the self-locking device, and one elastic sleeve ring 410 is matched.

In order to prevent the elastic collar 410 from falling off the friction seat 400, the circumferential surface of the first protrusion 403 is provided with an outwardly protruding surrounding edge 404, the elastic collar 410 is located between the surrounding edge 404 and the friction base 401, and the protruding surrounding edge 404 can limit the elastic collar 410 and limit the elastic collar 410 between the surrounding edge 404 and the friction base 401, so that in the working process, if no axial force acts on the elastic collar 410, the elastic collar 410 cannot be separated from the friction seat 400, and the whole structure is stable.

In order to fix the friction base 401 conveniently and avoid the friction base 401 from rotating synchronously with the shaft body, the end of the friction base 401 is further provided with a second protruding portion 405 arranged along the periphery of the friction base 401, the first protruding portion 403 and the second protruding portion 405 are arranged on the same side to avoid that the interference between the self-locking mechanism and the shaft body and between the self-locking mechanism and the linear actuator is reduced due to the fact that the self-locking mechanism is subjected to torque in the radial direction, and therefore self-locking force is reduced, after the second protruding portion 405 is arranged, the thickness of the friction base 400 is increased, fixing is more convenient, and rotation limitation of the friction base is easier.

The friction seat 400 further comprises a framework (not shown), and a rubber piece formed by the friction base 401, the first protruding portion 403 and the second protruding portion 405 wraps the framework, so that the framework is not prone to deformation, and the friction seat 400 between the framework and the shell can generate larger reaction force to generate larger friction force between the friction seat 400 and the shell to limit rotation of the self-locking mechanism.

In order to facilitate the production of the friction seat 400, the first boss 403, the second boss 405 and the friction base 401 are integrally formed, and the elastic collar 410 is sleeved on the first boss 403 in the subsequent installation.

Referring to fig. 2 and 3, based on the above embodiment, in another embodiment of the present invention, the first protrusion 403 is annular, the elastic collar 410 is annular, the inner ring of the elastic collar 410 is a continuous curved surface, and the annular elastic collar 410 can be in close contact with the first protrusion 403 to apply uniform acting force to the periphery of the shaft body, so as to avoid the local wear of the friction seat 400 from being serious, thereby prolonging the life of the self-locking mechanism.

If the outer circumference of the first protrusion 403 is square, the elastic collar 410 may have different frictional forces due to different forces acting on different portions of the shaft body through the first protrusion 403, so that the first protrusion 403 may be partially worn. If the profile of the elastic collar 410 is designed to be square, more raw material of the elastic collar 410 is required compared to the ring structure, which increases the production cost.

Referring to fig. 4 and 5, based on the above embodiment, in another embodiment of the present invention, the self-locking mechanism is disposed on the worm 220, specifically:

the driver 100 comprises a shell 110 and a motor arranged in the shell 110, wherein an end cover 120 is mounted at the end of the shell 110, the worm 220 penetrates through the end cover 120, a mounting groove 130 for accommodating the self-locking mechanism is formed in one side of the end cover 120 facing the shell 110, and the friction seat 400 is in interference fit with the mounting groove 130. The side of the housing 110 facing the end cap 120 may also be provided with mounting slots 130 for mounting the self-locking mechanism.

The friction seat 400 is annular, the mounting groove 130 is matched with the friction seat 400 in shape and is a circular accommodating groove, the self-locking mechanism is mounted in the mounting groove 130, the friction seat 400 and the mounting groove 130 are in interference fit, when the worm 220 rotates, friction force between the worm 220 and the friction seat 400 can enable the friction seat 400 to have a tendency of rotating, and static friction force can be generated between the friction seat 400 and the mounting groove 130 at the moment to limit the rotation of the self-locking mechanism so as to ensure the braking capacity of the self-locking mechanism on the shaft body; when the worm 220 has a tendency to rotate, the static friction between the friction seat 400 and the worm 220 also causes the friction seat 400 to have a tendency to rotate, and the static friction between the friction seat 400 and the mounting groove 130 is still provided to keep the position of the friction seat 400 unchanged.

Since the rotation of the screw rod 310 and the worm wheel 210 is driven by the worm 220, when the worm 220 stops rotating, the screw rod 310 and the worm wheel 210 can immediately stop rotating, so as to ensure the control precision of the upright 300.

Referring to fig. 4 and 6, unlike the above embodiment, in another embodiment of the present invention, the self-locking mechanism is disposed on the worm wheel 210, specifically:

the transmission part 200 further comprises a worm wheel mounting seat 230, and the friction seat 400 is sleeved on the hub 211 of the worm wheel 210 and is in interference fit with the worm wheel mounting seat 230. Meanwhile, the worm wheel mounting seat 230 is also used for mounting the worm wheel 210, the worm wheel mounting seat 230 is provided with a convex edge arranged on the periphery of the hub 211 of the worm wheel 210, and the outer ring of the friction seat 400 is abutted against the convex edge, so that the worm wheel 210 can be self-locked. The worm wheel 210 rotates at a much slower speed than the worm 220, which reduces the wear of the friction seat 400. Both sides of worm wheel 210 are provided with wheel hub 211, can set up two self-locking mechanism on worm wheel 210 to improve auto-lock and braking capability.

Referring to fig. 7 and 8, unlike the above embodiments, in another embodiment of the present invention, the self-locking mechanism is disposed on the screw rod 310, specifically:

the shaft 300 further includes a sleeve 320 and a sleeve mounting seat 330 disposed in the sleeve 320, the screw rod 310 is disposed in the sleeve 320 and rotatably connected to the sleeve mounting seat 330, and the friction seat 400 is sleeved on the screw rod 310 and is in interference fit with the sleeve mounting seat 330. The inner tube 340 and the nut 350 mounted on the lead screw 310 are arranged in the sleeve 320, the lead screw 310 can drive the nut 350 to axially move along the lead screw 310 when rotating, the inner tube 340 is pushed to stretch, and the friction seat 400 exerts self-locking force on the lead screw 310 to realize braking and self-locking. Of course, the friction seat 400 may also be configured to have an interference fit with the sleeve 320, so as to reduce the shaking of the sleeve 320 during the movement of the nut 350.

The utility model also discloses a lift platform, lift platform include base and elevating platform, and the elevating platform can go up and down the activity relatively the base, is equipped with foretell linear actuator on the base and provides lift power for the elevating platform, and lift platform can be for furniture such as lift table, lift bed, also can be for being used for practical tool such as the lift objective table of year thing. The lifting precision and the descending precision of the lifting platform are accurately controlled by the linear actuator, the lifting process can be stopped in time, and the lifting platform is in a self-locking state when in a static state, so that the lifting platform cannot descend due to accidents.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and those skilled in the art should understand that the present invention includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification which does not depart from the functional and structural principles of the present invention is intended to be included within the scope of the claims.

Claims

1. The linear actuator comprises a driver, a transmission part and an upright post, wherein the transmission part comprises a worm wheel and a worm, the upright post comprises a screw rod, and the linear actuator is characterized in that at least one of a hub of the worm wheel, the worm and the screw rod is provided with a self-locking mechanism, the self-locking mechanism comprises a friction seat and an elastic lantern ring, the friction seat is sleeved on a shaft body of the linear actuator and is in interference fit with the shaft body so as to apply braking force to the shaft body, and the elastic lantern ring is installed on the friction seat and has acting force acting in the radial direction of the shaft body and is used for keeping the interference fit of the friction seat and the shaft body so as to realize bidirectional self-locking of the shaft body.

2. The linear actuator of claim 1, wherein the friction seat includes a friction base and a circular opening extending through the friction base, an inner race surface of the circular opening abutting the shaft body.

3. The linear actuator of claim 2, wherein the friction base has an end provided with a first boss disposed along a periphery of the circular opening, an inner race of the first boss being connected to the inner race of the circular opening.

4. A linear actuator as claimed in claim 3, wherein the resilient collar is mounted on the periphery of the first boss and is an interference fit with the first boss.

5. Linear actuator according to claim 4, characterized in that the circumferential surface of the first elevation is provided with an outwardly protruding skirt, the elastic collar being located between the skirt and the friction base.

6. The linear actuator of claim 3, wherein the end of the friction base is further provided with a second protrusion disposed along the circumference of the friction base, and the first protrusion and the second protrusion are disposed on the same side.

7. The linear actuator of claim 6, wherein the friction base, the first boss, and the second boss are integrally formed rubber pieces.

8. A linear actuator as claimed in any one of claims 1 to 7, wherein the self-locking mechanism further comprises a skeleton which is enclosed by the friction seat.

9. Linear actuator according to any of claims 1 to 7, characterized in that the elastic collar is a plastic, ceramic or metal piece, the inner ring of which is closed over its circumference.

10. A linear actuator as claimed in any one of claims 1 to 7, wherein the drive further comprises a motor and an end cap, the worm being the drive shaft of the motor, the friction seat being fitted over the worm and being an interference fit with the end cap.

11. A linear actuator as claimed in any one of claims 1 to 7, wherein the transmission part further comprises a worm gear mounting, the friction seat being fitted over the hub of the worm gear and being an interference fit with the worm gear mounting.

12. The linear actuator of any one of claims 1 to 7, wherein the post further comprises a sleeve, a sleeve mount disposed within the sleeve, the lead screw disposed within the sleeve and rotationally coupled to the sleeve mount, and the friction seat is mounted on the lead screw and is in interference fit with the sleeve mount or the sleeve.

13. Lifting platform, characterized in that it comprises a linear actuator according to any of claims 1 to 12.