Electric linear drive for furniture and electric furniture

Abstract

The present application relates to the field of furniture, and discloses a linear driver for electric furniture and electric furniture, wherein the linear driver for electric furniture comprises a shell, a worm rod inserted into the shell, a worm wheel arranged in the shell and engaged with the worm rod, and a lead screw, the lead screw is threaded with the worm wheel and penetrates through the worm wheel, at least one end of the lead screw is out of the shell for connecting a movable part of the electric furniture, the worm wheel is arranged to limit its axial movement relative to the lead screw, at least one end of the worm wheel is provided with a guide structure, the guide structure is sleeved on the lead screw and gap-fitted with the lead screw, and the guide structure is fixed relative to the worm wheel or the shell. The guide structure is additionally arranged at least at one end of the worm wheel, the guide structure is fixed relative to the shell or the worm wheel, the guide structure is sleeved on the lead screw and gap-fitted with the lead screw, the movement of the lead screw relative to the worm wheel is guided by the guide structure, the coaxiality of the lead screw and the worm wheel is improved, and the lead screw is prevented from tilting relative to the worm wheel so as to affect the normal movement of the lead screw.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of furniture, in particular to a linear drive for electric furniture and electric furniture. BACKGROUND

[0002] In order to make furniture such as tables, chairs and sofas have folding and lifting functions, a drive is usually provided. The commonly used drive in the furniture industry is a linear drive. There are mainly two kinds of linear drives. One kind of linear drive includes a lead screw, a worm gear sleeved on the lead screw and a worm gear engaged with the worm gear, and the worm gear is threadedly connected with the lead screw. The rotation of the worm gear drives the rotation of the worm wheel, so that the lead screw moves axially relative to the worm wheel.

[0003] However, during the rotation of the worm wheel, if the lead screw and the worm wheel are relatively inclined, the power source driving the worm wheel will be blocked. SUMMARY

[0004] The purpose of the present application is to provide a linear drive for electric furniture and electric furniture, which guides the movement of the lead screw relative to the worm wheel to ensure the coaxiality between the lead screw and the worm wheel.

[0005] To achieve this purpose, the present application adopts the following technical solutions:

[0006] A linear drive for electric furniture, comprising a housing, a worm gear extending into the housing, a worm wheel arranged in the housing and engaged with the worm gear, and a lead screw, the lead screw penetrating the worm wheel and being threadedly connected with the worm wheel, at least one end of the lead screw extending out of the housing for connecting a movable part of the electric furniture, the worm wheel being arranged to limit its axial movement relative to the lead screw; at least one end of the worm wheel is provided with a guide structure, the guide structure is sleeved on the outside of the lead screw and is in clearance fit with the lead screw, the guide structure is fixed relative to the worm wheel or the housing.

[0007] As a preferred technical solution of the above-mentioned linear drive for electric furniture, the guide structure is integrally arranged with the worm wheel;

[0008] Or, the guide structure is arranged on the housing;

[0009] Or, the guide structure is arranged separately from the housing and is fixed relative to the housing.

[0010] As a preferred technical solution of the above-mentioned linear drive for electric furniture, one end or both ends of the worm wheel are provided with a light rim part integrally formed thereon, the light rim part is provided with a guide hole, the lead screw penetrates the guide hole and is in clearance fit with the inner wall of the guide hole, and the guide structure is the guide hole.

[0011] As a preferred technical scheme of the electric furniture linear drive, the shell comprises a first shell and a second shell connected with each other, and the first shell and the second shell are both provided with arc-shaped grooves, the arc-shaped grooves on the first shell and the arc-shaped grooves on the second shell correspond to each other and are oppositely opened, the oppositely opened arc-shaped grooves form a guide hole, the lead screw passes through the guide hole and is in clearance fit with the inner wall of the guide hole, and the guide structure is the guide hole.

[0012] As a preferred technical scheme of the electric furniture linear drive, the lead screw is sleeved with a sleeve fixed relative to the shell, and the inner wall of the sleeve is in clearance fit with the lead screw to form the guide structure.

[0013] As a preferred technical scheme of the electric furniture linear drive, the inner wall of the hole in clearance fit with the lead screw is provided with a first oil storage groove.

[0014] As a preferred technical scheme of the electric furniture linear drive, one end or both ends of the worm wheel are provided with light rim portions connected thereto, each of the light rim portions is sleeved with a support, and the light rim portion can rotate relative to the shell through the support; and the support is any one of a bearing and a shaft sleeve.

[0015] As a preferred technical scheme of the electric furniture linear drive, the inner wall of the shaft sleeve is provided with a second oil storage groove.

[0016] As a preferred technical scheme of the electric furniture linear drive, the shaft sleeve is fixed relative to the shell, and an elastic element is clamped between the shaft sleeve and the worm wheel.

[0017] As a preferred technical scheme of the electric furniture linear drive, the electric furniture linear drive further comprises a brake connected to the shell and sleeved outside the worm, the brake can be elastically deformed, and the brake is used for providing a brake force opposite to the rotation direction of the worm to the worm.

[0018] As a preferred technical scheme of the electric furniture linear drive, the shell is provided with a U-shaped portion used for connecting a fixed portion of the electric furniture.

[0019] As a preferred technical scheme of the electric furniture linear drive, the electric furniture linear drive further comprises a limiting assembly used for limiting the limit position of the movement of the lead screw.

[0020] As a preferred technical scheme of the electric furniture linear drive, the limiting assembly comprises:

[0021] a first limiting piece, the two ends of the lead screw are provided with first limiting pieces fixed relative to the lead screw.

[0022] Second limiting piece, the shell is equipped with the second limiting piece corresponding to the first limiting piece, one of the first limiting piece and the corresponding second limiting piece is the limiting switch connected with the power source, the other can make the limiting switch control and the power source stop action.

[0023] As a preferred technical scheme of the above-mentioned electric furniture linear drive, the end of the lead screw penetrating out of the shell is provided with a connecting hole for connecting a movable part of the electric furniture, or a connecting part fixed relative to the lead screw and used for connecting the movable part of the electric furniture is connected.

[0024] The application further provides an electric furniture comprising the above-mentioned electric furniture linear drive.

[0025] The electric furniture linear drive provided by the application has the following beneficial effects: the guide structure is additionally arranged at least at one end of the worm wheel, the guide structure is fixed relative to the shell or the worm wheel, the guide structure is sleeved on the lead screw and gap-fitted with the lead screw, the movement of the lead screw relative to the worm wheel is guided by the guide structure, the coaxiality of the lead screw and the worm wheel is improved, and the inclination of the lead screw relative to the worm wheel is avoided so as to affect the normal movement of the lead screw.

[0026] The electric furniture provided by the application comprises the above-mentioned electric furniture linear drive, the coaxiality of the worm wheel and the lead screw can be effectively improved, and the folding or lifting function of the electric furniture can be ensured to be normally used. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the application. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the contents of the embodiments of the application and the drawings.

[0028] Figure 1 is a structural schematic view of the electric furniture linear drive provided by the first embodiment of the application;

[0029] Figure 2 is an exploded view of the electric furniture linear drive provided by the first embodiment of the application;

[0030] Figure 3 is a sectional view of the electric furniture linear drive provided by the first embodiment of the application;

[0031] Figure 4 is a sectional view of the worm wheel provided by the first embodiment of the application;

[0032] Figure 5 is Figure 3 is a partial enlarged view of A in FIG. 1;

[0033] Figure 6 is Figure 3 is a partial enlarged view of B in FIG. 1;

[0034] Figure 7 is a structural schematic view of a second shell provided by an embodiment one of the present application;

[0035] Figure 8 is a structural schematic view of a brake provided by an embodiment one of the present application;

[0036] Figure 9 is an exploded view of an electric furniture linear drive provided by an embodiment two of the present application;

[0037] Figure 10 is a sectional view of an electric furniture linear drive provided by an embodiment two of the present application;

[0038] Figure 11 is Figure 10 is a partial enlarged view of C in FIG. 1;

[0039] Figure 12 is an exploded view of an electric furniture linear drive provided by an embodiment three of the present application.

[0040] in the figure:

[0041] 11, motor; 12, worm; 13, worm wheel; 131, light edge portion; 132, annular groove; 14, lead screw;

[0042] 21, first shell; 22, second shell; 23, U-shaped portion; 24, second positioning member; 25, motor front end cover; 250, through hole; 251, limiting step; 252, boss;

[0043] 3, guide structure; 31, third positioning member; 32, guide hole; 321, arc-shaped slot;

[0044] 41, bearing; 42, shaft sleeve; 421, first positioning member; 43, gasket; 44, elastic element;

[0045] 5, first limiting member;

[0046] 6, wire;

[0047] 7, brake; 71, notch; 72, cutout; 73, friction surface. DETAILED DESCRIPTION

[0048] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved more clearly, the technical solutions of the present invention are further described below with reference to the accompanying drawings and through specific embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the drawings only show portions relevant to the present invention, not all of them.

[0049] Example 1

[0050] like Figures 1 to 3 As shown, this embodiment provides a linear drive for electric furniture, including a housing, a worm 12 with one end extending into the housing, a worm wheel 13 arranged in the housing and meshing with the worm 12, and a screw 14, the screw 14 passes through the worm wheel 13 and is threadedly connected to the worm wheel 13, at least one end of the screw 14 passes through the housing for connecting to the movable part of the electric furniture, and the worm wheel 13 is configured to limit its axial movement relative to the screw 14.

[0051] The worm 12 rotates, driving the worm wheel 13 meshing with it to rotate, thereby causing the lead screw 14 to move axially, thereby driving the mounting frame of the electric furniture to move through the lead screw 14.

[0052] The electric furniture can be an electric sofa, an electric table and chair, or an electric bed, and the linear actuator is usually directly fixed to the fixed part of the electric furniture. Specifically, a U-shaped portion 23 is formed on the housing for connecting to the fixed part of the electric sofa frame or electric bed frame.

[0053] To connect the lead screw 14 to the movable part of the electric furniture, in this embodiment, one end of the lead screw 14 extends through the housing and is connected to a connector fixed thereto for connection to the movable part of the electric furniture. The connector can be integrally formed with the lead screw 14 or separately provided and fixed to the lead screw 14, without limitation.

[0054] In other embodiments, both ends of the lead screw 14 may pass through the housing and be connected to a connection portion fixed thereto.

[0055] In another embodiment, a connecting hole can be opened at at least one end of the screw 14 passing through the shell, and the screw 14 can be connected to the movable part of the electric furniture through the connecting hole. Preferably, an oil-containing sleeve or a bearing made of plastic is provided in the connecting hole, and the specific setting can be made according to actual needs.

[0056] The electric household linear driver further comprises a power source, which is a motor 11 in this embodiment. The output shaft of the motor 11 is integrally formed with or connected to the worm 12. The motor 11 is connected to a wire 6, which is used to connect a power supply and a control switch. The power supply is electrically connected to the motor 11 through the wire 6 to supply power to the motor 11. The control switch is electrically connected to the motor 11 through the wire 6 to control the rotation direction of the motor 11. In other embodiments, the power source can also be an electric machine.

[0057] Further, in order to limit the stroke of the lead screw 14, the electric household linear driver further comprises a limiting assembly for limiting the limit position of the movement of the lead screw 14. Specifically, the limiting assembly comprises a first limiting piece 5 and a second limiting piece. The two ends of the lead screw 14 pass through the housing and are connected to the first limiting piece 5. The first limiting piece 5 is sleeved on the lead screw 14 and is fixed relative to the lead screw 14 by a resilient pin shaft penetrating the first limiting piece 5 and the lead screw 14. The second limiting piece is a limit switch, preferably a micro switch, which is arranged on the housing and is electrically connected to the motor 11. During the movement of the lead screw 14 relative to the housing, once the second limiting switch contacts the first limiting piece, the motor will stop rotating, and the lead screw 14 will be kept in the current state. In other embodiments, the first limiting piece can also be a limit switch.

[0058] In order to improve the stability of the movement of the lead screw 14 relative to the worm 13, at least one end of the worm 13 is provided with a guide structure 3, which is sleeved on the lead screw 14 and gap-fitted with the lead screw 14, and is fixed relative to the worm 13. Preferably, both ends of the worm 13 are provided with the guide structure 3 to improve the stability of the movement of the lead screw 14. The specific gap size of the gap-fitted guide structure 3 and the lead screw 14 can be determined by repeated tests, which is not limited here.

[0059] In this embodiment, the guide structure 3 is integrally arranged with the worm 13. Specifically, as shown in Figures 3 to 5 both axial ends of the worm 13 are provided with a light rim portion 131 integrally formed therewith. The light rim portion 131 is provided with a guide hole 32, which is a light hole. The lead screw 14 passes through the guide hole 32. The inner wall of the guide hole 32 is gap-fitted with the lead screw 14 to form the guide structure 3. The guide structure 3 guides the movement of the lead screw 14 relative to the worm 13, improves the coaxiality of the lead screw 14 and the worm 13, and avoids the inclination of the lead screw 14 relative to the worm 13, which causes the motor 11 to be blocked.

[0060] Preferably, the inner wall of the guide hole 32 is provided with a first oil storage groove (not shown in the figure) for storing lubricating oil to lubricate the lead screw 14 and ensure the smoothness of the rotation of the lead screw 14.

[0061] Further, in order to facilitate the installation and replacement of the worm gear 13, the above-mentioned housing comprises a first housing 21 and a second housing 22, which are detachably connected. In the embodiment, the first housing 21 and the second housing 22 are connected by a plurality of circumferentially arranged screws. In other embodiments, the first housing 21 and the second housing 22 can also be connected by clamping or bolting, etc.

[0062] Further, in order to axially limit and support the worm gear 13, at least one of the light rim portions 131 is provided with a support member, and the light rim portion 131 can rotate relative to the housing through the support member. In the embodiment, one support member is a bearing 41, and the other support member is a shaft sleeve 42, so as to improve the stability of the worm gear 13. In other embodiments, only one light rim portion 131 can be provided with a support member, which can be a bearing 41 or a shaft sleeve 42. In order to axially limit the worm gear 13, the end face of the light rim portion 131 without the support member is required to abut against the inner wall of the housing.

[0063] Specifically, one of the light rim portions 131 is externally provided with the bearing 41, the inner ring of the bearing 41 is fixed relative to the light rim portion 131, and the outer ring of the bearing 41 is fixed relative to the housing; the other light rim portion 131 is externally provided with the shaft sleeve 42, and the shaft sleeve 42 is fixed relative to the housing. Preferably, the bearing 41 is a ball bearing, and the inner ring of the bearing 41 can be fixed relative to the light rim portion 131 by interference fit.

[0064] Since the outer ring of the bearing 41 is fixed relative to the housing, and the inner ring and the outer ring of the bearing 41 cannot axially move, the bearing 41 indirectly plays a role in axially limiting the worm gear 13. By supporting and axially limiting the worm gear 13 through the bearing 41 and the shaft sleeve 42, the stability of the lead screw 14 is improved.

[0065] Specifically, as shown in Figure 2 , Figure 3 and Figure 6 , the outer peripheral wall of the shaft sleeve 42 is provided with a first positioning member 421, the inner wall of the housing is provided with a second positioning member 24, and the first positioning member 421 and the second positioning member 24 are inserted and fitted to limit the axial movement and circumferential rotation of the shaft sleeve 42. In the embodiment, the first positioning member 421 is a protrusion, and the second positioning member 24 is a groove. Preferably, a plurality of first positioning members 421 are provided, which are uniformly distributed along the outer wall of the shaft sleeve 42, and the first positioning members 421 correspond to the second positioning members 24 one by one. In other embodiments, the first positioning member 421 can also be a groove, and the second positioning member 24 can be a protrusion.

[0066] Further, in order to avoid axial movement of the worm gear 13 during rotation, in the embodiment, the shaft sleeve 42 is fixed relative to the housing, and an elastic element 44 is arranged between the shaft sleeve 42 and the worm gear 13. Specifically, the side of the worm gear 13 facing the shaft sleeve 42 is provided with an annular groove 132, and the elastic element 44 is arranged in the annular groove 132. A gasket 43 is arranged between the worm gear 13 and the shaft sleeve 42, and the outer diameter of the gasket 43 is greater than the maximum outer diameter of the annular groove 132, so that the gasket 43 can abut against the axial end surface of the worm gear 13. The gasket 43 is pressed by the shaft sleeve 42 to compress the elastic element 44 into the annular groove 132. The elastic element 44 is deformed to dampen vibration, thereby preventing axial movement of the worm gear 13. Preferably, the gasket 43 is a wave-shaped gasket, and the elastic element 44 is a rubber element.

[0067] In other embodiments, two shaft sleeves 42 can be used to support and axially limit the worm gear 13. One shaft sleeve 42 is arranged on each light rim portion 131, and the shaft sleeves 42 are fixed relative to the inner wall of the housing. Specifically, a gasket 43 is arranged between each shaft sleeve 42 and the axial end surface of the worm gear 13 to prevent the worm gear 13 and the shaft sleeves 42 from being assembled to the point of being stuck. One axial end surface of the worm gear 13 is provided with an annular groove 132, and an elastic element 44 is arranged in the annular groove 132. The elastic element 44 abuts against the gasket 43. One side of the worm gear 13 is limited by the shaft sleeve 42, and the other side of the worm gear 13 is limited by the elastic element 44 in cooperation with the shaft sleeve 42, thereby preventing axial movement of the worm gear 13 during rotation.

[0068] In other embodiments, two bearings 41 can be used to support and axially limit the worm gear 13. Specifically, one bearing 41 can be arranged on each light rim portion 131 at the two ends of the worm gear 13. The inner ring of the bearing 41 is fixed relative to the light rim portion 131, and the outer ring of the bearing 41 is fixed relative to the housing. The two bearings 41 simultaneously axially limit the worm gear 13, thereby preventing axial movement of the worm gear 13 during rotation.

[0069] Further, the inner wall of the shaft sleeve 42 is provided with a second oil storage groove (not shown in the figure) for storing lubricating oil to lubricate the light rim portion 131 and ensure smooth rotation of the worm gear 13.

[0070] Further, as shown in FIG. 6, the worm gear 13 is provided with a plurality of lubricating oil injection holes 133, and the housing is provided with a plurality of lubricating oil injection holes 134. The lubricating oil injection holes 133 and the lubricating oil injection holes 134 are arranged in a staggered manner, and the lubricating oil injection holes 133 and the lubricating oil injection holes 134 are arranged in a staggered manner. Figure 7 and Figure 8As shown, the above-mentioned electric furniture linear drive further comprises a brake 7 connected to the shell and sleeved outside the worm 12, the brake 7 can be elastically deformed to provide a brake force opposite to the rotation direction of the worm 12 for the worm 12. Specifically, the outer side of the second shell 22 is connected with a motor front end cover 25, the motor front end cover 25 is provided with a through hole 250, the inner wall of the through hole 250 is provided with a plurality of circumferentially arranged limiting steps 251, at least one limiting step 251 is provided with a boss 252. The outer peripheral wall of the brake 7 is provided with a plurality of notches 71, the notches 71 correspond one-to-one with the bosses 252 and are inserted and matched with each other, so that the brake 7 is fixed on the motor front end cover 25 and cannot rotate.

[0071] The outer wall of one end of the worm 12 close to the motor 11 is a cylindrical surface without worm teeth, the free end of the worm 12 passes through the brake 7 and extends into the second shell 22, the brake 7 is provided with a plurality of cutouts 72, the cutouts 72 and the notches 71 are alternately arranged along the circumference of the brake 7, the cutouts 72 and the notches 71 provide space for the elastic deformation of the brake 7, the surface of the brake 7 in contact with the worm 12 forms a friction surface 73, during the rotation of the worm 12, the friction surface 73 cooperates with the cylindrical surface without worm teeth on the worm 12 to provide a brake force for the worm 12. The specific structure of the brake 7 and how the brake 7 brakes the worm 12 are prior art, which will not be described in detail here.

[0072] In order to avoid damage to the surface of the worm 12 by the brake 7 during the rotation of the worm 12, it is required that the material hardness of the brake 7 is less than the material hardness of the worm 12.

[0073] The embodiment also provides an electric furniture comprising the above-mentioned electric furniture linear drive, which can improve the coaxiality of the lead screw 14 and the worm wheel 13, effectively prevent the motor 11 from being blocked due to the inclination of the lead screw 14 relative to the worm wheel 13, and ensure the normal use of the folding or lifting function of the electric furniture.

[0074] Embodiment two

[0075] As Figures 9 to 11The difference between the present embodiment and embodiment one is that the structure of the guide structure 3 is different. In the present embodiment, the guide structure 3 is arranged on the shell. Specifically, the first shell 21 and the second shell 22 are each provided with an arc-shaped groove 321, the arc-shaped grooves 321 on the first shell 21 and the second shell 22 correspond to each other and are oppositely open, and the oppositely open arc-shaped grooves 321 enclose a guide hole 32, the inner wall of the guide hole 32 is in clearance fit with the lead screw 14 to form the above-mentioned guide structure 3. By using the clearance fit between the inner wall of the guide hole 32 and the lead screw 14, the lead screw 14 is guided to avoid tilting of the lead screw 14, thereby ensuring the stability of the movement and rotation of the lead screw 14. In the present embodiment, the above-mentioned guide hole 32 is provided with two, and the two guide holes 32 are respectively located at the axial ends of the worm wheel 13, and the two ends of the lead screw 14 pass out of the shell from the two guide holes 32.

[0076] Preferably, the inner wall of the guide hole 32 is provided with a first oil storage groove for storing lubricating oil to lubricate the lead screw 14, thereby ensuring the smoothness of the rotation of the lead screw 14.

[0077] In order to limit the worm wheel 13, the two ends of the worm wheel 13 are provided with light rim portions 131, and each light rim portion 131 is sleeved with a support, and the support is a shaft sleeve 42 fixed relative to the shell. Specifically, the outer peripheral wall of the shaft sleeve 42 is provided with a first positioning member 421, and the inner wall of the shell is provided with a second positioning member 24, and the first positioning member 421 and the second positioning member 24 are inserted and fitted to limit the axial movement and circumferential rotation of the shaft sleeve 42. In the present embodiment, the first positioning member 421 is a protrusion, and the second positioning member 24 is a groove. Preferably, the above-mentioned first positioning member 421 is provided with a plurality of first positioning members 421, which are uniformly distributed along the outer wall of the shaft sleeve 42 in the circumferential direction, and the first positioning member 421 corresponds to the second positioning member 24. In other embodiments, the first positioning member 421 can also be provided as a groove, and the second positioning member 24 is provided as a protrusion.

[0078] Further, in order to prevent the shaft sleeve 42 and the worm wheel 13 from being jammed during assembly, a gasket 43 is arranged between each shaft sleeve 42 and the axial end face of the worm wheel 13 opposite to it. Preferably, the gasket 43 is a wave-shaped gasket.

[0079] Further, in order to prevent the worm wheel 13 from axially moving during rotation, an elastic element 44 is arranged between one of the shaft sleeves 42 and the end face of the worm wheel 13 opposite to it in the present embodiment. Specifically, one axial end face of the worm wheel 13 is provided with an annular groove 132, and the elastic element 44 is installed in the annular groove 132, the gasket 43 abuts against the elastic element 44, and the shaft sleeve 42 abuts against the gasket 43. The elastic element 44 is deformed to dampen vibration, thereby preventing the worm wheel 13 from axially moving.

[0080] Preferably, a second oil storage tank is provided on the inner wall of the shaft sleeve 42 for storing lubricating oil to lubricate the outer wall of the optical edge portion 131 to ensure smooth rotation of the worm gear 13 .

[0081] In other embodiments, a bearing 41 may be sleeved on each optical edge portion 131 , with the inner ring of the bearing 41 fixed relative to the worm gear 13 and the outer ring of the bearing 41 fixed relative to the housing, to replace the above-mentioned sleeve 42 .

[0082] In other embodiments, a bearing 41 can be sleeved on one of the optical edge portions 131, with the inner ring of the bearing 41 fixed relative to the worm gear 13, and the outer ring of the bearing 41 fixed relative to the housing. A shaft sleeve 42 fixed relative to the housing is sleeved on the other optical edge portion 131. A gasket 43 is provided between the shaft sleeve 42 and the axial end face of the worm gear 13 opposite to it to prevent the shaft sleeve 42 and the worm gear 13 from being stuck during assembly. An annular groove 132 is provided on an axial end face of the worm gear 13, and an elastic element 44 is installed in the annular groove 132. The gasket 43 abuts against the elastic element 44, and the shaft sleeve 42 abuts against the gasket 43. The deformation of the elastic element 44 is used to reduce vibration, thereby preventing the worm gear 13 from axially moving.

[0083] Example 3

[0084] like Figure 12 As shown, the difference between this embodiment and other embodiments is that the structure of the guide structure 3 is different. In this embodiment, the guide structure 3 is set separately from the housing and the worm gear 13 and is fixed relative to the housing. Specifically, the guide structure 3 is a sleeve, and the sleeve is sleeved outside the screw 14, and the inner wall of the sleeve is clearance-matched with the screw 14. The outer peripheral wall of the sleeve is provided with a third positioning member 31, and the inner wall of the housing is provided with a fourth positioning member, and the third positioning member 31 and the fourth positioning member are plug-fitted to limit the axial movement and circumferential rotation of the sleeve. In this embodiment, the third positioning member 31 is a protrusion, and the fourth positioning member is a groove. Preferably, the above-mentioned third positioning member 31 is provided in plurality, and the plurality of third positioning members 31 are evenly distributed along the circumference of the outer wall of the sleeve, and the fourth positioning member corresponds one-to-one to the third positioning member 31. In other embodiments, the third positioning member 31 can also be set as a groove, and the fourth positioning member can be set as a protrusion.

[0085] Preferably, a first oil storage groove is provided on the inner wall of the sleeve to lubricate the lead screw 14 , thereby ensuring smooth rotation of the lead screw 14 .

[0086] Further, the worm wheel 13 is provided with a light rim 131 at each axial end, and each light rim 131 is sleeved with a support, which is a bearing 41. The inner ring of the bearing 41 is fixed relative to the light rim 131, and the outer ring of the bearing 41 is fixed relative to the shell. The worm wheel 13 is supported and axially limited by the two bearings 41. The worm wheel 13 is axially limited to prevent axial movement during rotation.

[0087] In other embodiments, a sleeve 42 fixed relative to the shell can be sleeved on each light rim 131. In other embodiments, a sleeve 42 fixed relative to the shell can be sleeved on one light rim 131, and a bearing 41 can be sleeved on the other light rim 131. The inner ring of the bearing 41 is fixed relative to the light rim 131, and the outer ring of the bearing 41 is fixed relative to the shell. The above two specific ways of supporting and axially limiting the worm wheel 13 are the same as described above, and will not be repeated here.

[0088] Embodiment Four

[0089] In this embodiment, the guide structure 3 is provided with two guide structures 3 at the two ends of the worm wheel 13. The difference between this embodiment and other embodiments is that one guide structure 3 is the guide hole 32 in the light rim 131 in the first embodiment and is in clearance fit with the lead screw 14, and the other guide structure 3 is the guide hole 32 in the shell in the second embodiment and is in clearance fit with the lead screw 14.

[0090] In other embodiments, one guide structure 3 can be the guide hole 32 in the light rim 131 in the first embodiment and be in clearance fit with the lead screw 14, and the other guide structure 3 can be the sleeve in the third embodiment and be in clearance fit with the lead screw 14.

[0091] In other embodiments, one guide structure 3 can be the guide hole 32 in the shell in the second embodiment and be in clearance fit with the lead screw 14, and the other guide structure 3 can be the sleeve in the third embodiment and be in clearance fit with the lead screw 14.

[0092] Obviously, the above embodiments of the present application are merely exemplary and are not intended to limit the embodiments of the present application. Based on the above description, those skilled in the art can make other different forms of changes or modifications. Here, it is not necessary or possible to exhaust all the embodiments. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

[0093] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and 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 cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0094] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

Claims

1. A linear actuator for electric furniture, comprising a housing, a worm (12) with one end extending into the housing, a worm wheel (13) disposed in the housing and meshing with the worm (12), and a lead screw (14), wherein the lead screw (14) passes through the worm wheel (13) and is threadedly connected to the worm wheel (13), at least one end of the lead screw (14) passes through the housing for connection to a movable part of the electric furniture, and the worm wheel (13) is configured to limit its axial movement relative to the lead screw (14); characterized in that At least one end of the worm wheel (13) is provided with a guide structure (3), the guide structure (3) is sleeved outside the lead screw (14) and is clearance-matched with the lead screw (14), and the guide structure (3) is fixed relative to the worm wheel (13) or the housing; The guide structure (3) and the worm gear (13) are integrally arranged; Alternatively, the guide structure (3) is provided on the housing; Alternatively, the guide structure (3) is provided separately from the housing and is fixed relative to the housing; One or both axial ends of the worm wheel (13) are provided with an optical edge portion (131) integrally formed therewith, the optical edge portion (131) is provided with a guide hole (32), the lead screw (14) passes through the guide hole (32) and is clearance-matched with the inner wall of the guide hole (32), and the guide structure (3) is the guide hole (32); A first oil storage groove is provided on the inner wall of the hole in which the guide structure (3) and the lead screw (14) are clearance-matched; One or both axial ends of the worm wheel (13) are provided with an optical edge portion (131) connected thereto, and each optical edge portion (131) is sleeved with a support member, and the optical edge portion (131) can rotate relative to the housing through the support member; the support member is any one of a bearing (41) and a sleeve (42); The inner wall of the shaft sleeve (42) is provided with a second oil storage groove; The housing comprises a first housing (21) and a second housing (22) connected to each other, and an arc groove (321) is provided on the first housing (21) and the second housing (22), and the arc groove (321) on the first housing (21) corresponds to the arc groove (321) on the second housing (22) one by one and their openings are opposite to each other, and the arc grooves (321) with opposite openings form a guide hole (32), and the lead screw (14) passes through the guide hole (32) and is loosely matched with the inner wall of the guide hole (32), and the guide structure (3) is the guide hole (32); and the housing further comprises a brake member (7) connected to the housing and sleeved on the outside of the worm (12), and the brake member (7) can undergo elastic deformation and is used to provide the worm (12) with a contact with the guide hole (32). The braking force is opposite to the rotation direction of the worm (12); the outer side of the second shell is connected to the front end cover of the motor, the front end cover of the motor is provided with a through hole, the inner wall of the through hole is provided with a plurality of circumferentially arranged limiting steps, at least one limiting step is provided with a boss, the outer peripheral wall of the brake member is provided with a plurality of notches, the notches and the bosses correspond one to one and are plugged into each other so that the brake member is fixed to the front end cover of the motor in a non-rotatable manner; the outer wall of the worm close to the motor is a cylindrical surface without worm teeth, the free end of the worm passes through the brake member and extends into the second shell, the brake member is provided with a plurality of cuts, the cuts and the notches are alternately arranged along the circumference of the brake member, and space is provided for the elastic deformation of the brake member by setting the cuts and notches, the surface where the brake member contacts the worm forms a friction surface, and during the rotation of the worm, the friction surface cooperates with the cylindrical surface of the worm without worm teeth.

2. The linear actuator for electric furniture according to claim 1, characterized in that: The outer shell of the lead screw (14) is provided with a sleeve fixed relative to the housing, and the inner wall of the sleeve is clearance-matched with the lead screw (14) to form the guide structure (3).

3. The linear actuator for electric furniture according to claim 1, characterized in that: The shaft sleeve (42) is fixed relative to the housing, and an elastic element (44) is sandwiched between the shaft sleeve (42) and the worm gear (13).

4. The linear actuator for electric furniture according to any one of claims 1 to 2, characterized in that: The housing is provided with a U-shaped portion (23) for connecting to a fixing portion of the electric furniture.

5. The linear actuator for electric furniture according to any one of claims 1 to 2, characterized in that: The linear driver for electric furniture further comprises a limit assembly for limiting the extreme position of the movement of the lead screw (14).

6. The linear actuator for electric furniture according to claim 5, characterized in that: The limiting component includes: A first limiting member, wherein both ends of the lead screw (14) are provided with first limiting members (5) fixed relative thereto; A second limiting member is provided on the housing and corresponds to the first limiting member (5) one by one. One of the first limiting member and the corresponding second limiting member is a limit switch electrically connected to a power source connected to the worm (12), and the other is capable of enabling the limit switch to control the power source to stop moving.

7. The linear actuator for electric furniture according to any one of claims 1 to 2, characterized in that: The end of the lead screw (14) passing through the housing is provided with a connection hole for connecting to the movable part of the electric furniture, or is connected to a connection part fixed relative to the lead screw (14) and used to connect to the movable part of the electric furniture.

8. An electric furniture, characterized in that: The linear actuator for electric furniture comprises the linear actuator for electric furniture according to any one of claims 1 to 7.

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