CN210094992U

CN210094992U - Lifting upright post

Info

Publication number: CN210094992U
Application number: CN201920151116.3U
Authority: CN
Inventors: 封新稳; 郁奇苗
Original assignee: CHANGZHOU TIANAN NIKODA ELECTRONIC Co Ltd
Current assignee: CHANGZHOU TIANAN NIKODA ELECTRONIC Co Ltd
Priority date: 2019-01-22
Filing date: 2019-01-22
Publication date: 2020-02-21
Anticipated expiration: 2029-01-22

Abstract

The utility model discloses a lifting column, include: the screw rod mechanism comprises an outer pipe, an inner pipe nested in the outer pipe, a middle pipe arranged in the inner pipe, and a screw rod mechanism arranged in the middle pipe; the bottom of the outer pipe is fixedly connected with the bottom plate; the screw rod mechanism comprises a first screw rod assembly, a second screw rod assembly and a sleeve, wherein the second screw rod assembly is sleeved on the outer side of the first screw rod assembly; the first screw rod assembly comprises a first screw rod and a first nut sleeved on the first screw rod; the first nut is fixedly connected with one axial end part of the sleeve through a locking screw; the bottom of the sleeve is connected with the inner pipe; the second screw rod assembly comprises a second screw rod sleeved on the outer side of the first screw rod and a second nut sleeved on the second screw rod; one axial end of the second screw rod is rotationally connected with the first screw nut.

Description

Lifting upright post

Technical Field

The utility model relates to the technical field of mechanical equipment, especially, relate to a lifting column.

Background

Lifting columns are widely used in furniture products, such as table legs of lifting tables, and a screw mechanism is generally used in the lifting column to lift the column. The length of the lead screw is determined according to the telescopic range of the length of the lifting pipe, therefore, in order to effectively satisfy the lifting height of the lifting pipe, the length of the lead screw which is often needed is long, and the lead screw is converted into the linear lifting motion process through the rotation operation, in order to guarantee the axial stability of the lifting pipe after lifting, the two ends of the axial direction of the lead screw are required to be fixed, for example, the connecting bearings are arranged at the two ends of the axial direction of the lead screw, so that the trouble of complex structure assembly is caused, and the maintenance is inconvenient. Therefore, in the technical field of the lifting pipe, the reasonability of the design of the screw rod mechanism directly influences the lifting range of the lifting pipe and the running stability of the lifting pipe.

In addition, the power component among the screw mechanism among the prior art usually directly links to each other with the screw component, for example the patent two-stage lead screw linkage elevating gear of publication No. CN203146732U, power component includes motor and main part pipe, and the motor is installed at the intraductal rear portion of main part, and the first order lead screw is installed at the intraductal front portion of main part, and the terminal and the motor output end of first order lead screw link to each other, and this kind of structure is the lead screw structure commonly used, and at the rotatory in-process of motor drive lead screw, wearing and tearing appear even damage easily with the bearing that the. Particularly, for the two-stage screw rod structure, because the stroke of the integral screw rod is long, after the stroke of the first-stage screw rod is completed, a power structure is needed to realize the operation of the second-stage screw rod, the reaction force caused by the direct connection between the motor and the screw rod is large, the direct connection relation between the output shaft of the motor and the screw rod is point-point, and the bearing connected with the screw rod is easy to wear due to the action force at the point-point connection between the output shaft of the motor and the screw rod formed by the operation of the two-stage screw rod, so that the operation stability and the service life of the integral screw rod mechanism are influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a lifting stand to the technical problem of the stability of lead screw operation in-process in the solution improvement lifting stand.

The utility model discloses a lift stand realizes like this:

a lifting column, comprising: the screw rod mechanism comprises an outer pipe, an inner pipe nested in the outer pipe, a middle pipe arranged in the inner pipe, and a screw rod mechanism arranged in the middle pipe;

the bottom of the outer pipe is fixedly connected with the bottom plate;

the screw rod mechanism comprises a first screw rod assembly, a second screw rod assembly and a sleeve, wherein the second screw rod assembly is sleeved on the outer side of the first screw rod assembly, and the sleeve is sleeved on the outer side of the second screw rod assembly; wherein

The first screw rod assembly comprises a first screw rod and a first nut sleeved on the first screw rod; the first nut is fixedly connected with one axial end part of the sleeve through a locking screw; the bottom of the sleeve is connected with the inner pipe;

the second screw rod assembly comprises a second screw rod sleeved on the outer side of the first screw rod and a second screw nut sleeved on the second screw rod; and one axial end of the second screw rod is rotationally connected with the first screw nut.

In a preferred embodiment of the present invention, a spline housing is fixedly connected to an end of the first lead screw, which is far away from the first nut, through a screw; and

and an inner tooth structure which is suitable for being matched and nested with the spline housing is arranged on the inner side wall of the second screw rod so that the second screw rod and the first screw rod can synchronously rotate.

In a preferred embodiment of the present invention, the first nut includes a base portion sleeved with the first lead screw, and a wing portion integrally disposed outside the base portion and having an annular structure; a concave area with an annular structure is formed between the main part and the wing part;

the end part of the second screw rod is inserted into the recessed area and connected with the wing part;

the end part of the second screw rod is connected with the side end of the wing part facing to the main part through a bearing.

In a preferred embodiment of the present invention, a limit stop is sleeved on the outer side of the end of the second screw rod far away from the end connected with the first screw nut; the second screw rod is suitable for rotating relative to the limit stop;

the limit stop and the second nut are uniformly and fixedly connected with the vertical pipe;

the vertical pipe is coaxially arranged with the sleeve, and the bottom of the vertical pipe is fixedly connected with the bottom plate.

In a preferred embodiment of the present invention, the first screw rod is connected to the power assembly to enable the power assembly to drive the first screw rod to rotate;

the power assembly comprises a second rotation transmission unit connected with the first screw rod, a first rotation transmission unit connected with the second rotation transmission unit, and a driving motor connected with the first rotation transmission unit.

In a preferred embodiment of the present invention, the bottom wall of the inner tube is provided with a connecting block;

the connecting block is fixedly connected with the bottom of the sleeve through a fastening screw; the middle pipe is positioned in a gap between the inner pipe and the sleeve; the connecting block surrounds the circumferential outer side of the vertical pipe so that the connecting block can slide along the outer side wall of the vertical pipe;

the first rotation transmission unit and the second rotation transmission unit are arranged in the inner cavity of the middle pipe and are positioned above the sleeve.

In a preferred embodiment of the present invention, the first rotation transmission unit includes a first master gear fixedly connected to the output shaft of the driving motor, three first slave gears arranged at intervals and respectively meshed with the first master gear, and a first gear ring sleeved outside the three first slave gears and simultaneously meshed with the three first slave gears;

the second rotation transmission unit comprises a first linkage plate, a protruding shaft, a second main gear, three second driven gears and a second gear ring, wherein the first linkage plate is simultaneously connected with the three first driven gears, the protruding shaft is integrally connected with the first linkage plate and is positioned on the end face, away from the first driven gears, of the linkage plate, the second main gear is fixedly connected with the protruding shaft, the second driven gears are respectively meshed with the second main gear, the second driven gears are arranged at intervals, and the second gear ring is sleeved on the outer sides of the three second driven gears and is simultaneously meshed with the three second driven gears;

the three second slave gears are connected to the second linkage plate; and an engagement part used for being connected with the first-stage screw rod is arranged on the end face, deviating from the second driven gear, of the second linkage plate in a protruding mode.

In a preferred embodiment of the present invention, a first gap is formed between the first main gear and the first linkage plate; and

a second gap exists between the second main gear and the second linkage plate.

In the preferred embodiment of the present invention, a plurality of sliding pieces protruding from the side wall of the inner tube are provided at intervals on the side wall of the inner tube facing the appearance; the sliding sheet is abutted against the inner pipe wall of the outer pipe.

In the preferred embodiment of the present invention, an annular structure isolation ring is respectively arranged on the top of the inner pipe and the top of the outer pipe, which are away from the bottom plate;

the isolating ring on the inner pipe is abutted against the outer pipe wall of the middle pipe;

the spacer ring on the outer tube abuts the inner tube spacer ring.

By adopting the technical scheme, the utility model discloses following beneficial effect has: the utility model discloses a screw mechanism that lift stand adopted, nested first lead screw subassembly and the second lead screw subassembly that links to each other can be so that first lead screw and second lead screw when synchronous rotatory in-process drives the sleeve pipe and goes up and down, and the combination of two-stage lead screw can improve the stability that the sleeve pipe goes up and down. The combined mode of the two-stage screw rods can improve the overall telescopic range of the two-stage screw rods on the basis of not increasing the axial length of a single screw rod. On the other hand, to adopting the locking screw to realize the assembly between the sleeve pipe and the first screw nut, compare the riveting fixed mode, not only save riveting tools's use, convenient to detach maintains moreover.

Further, to the utility model discloses a two tip of first lead screw and second lead screw axis direction do not all set up the bearing again at the tip of keeping away from power component, but realize both synchronous revolution and radial relatively fixed and guarantee the stability of two lead screw rotation processes through the spline housing between two lead screws, so reduce the problem production that needs the maintenance appear because of the wearing and tearing of bearing.

Still further, a first rotation transmission unit and a second rotation transmission unit are arranged between the driving motor and the first screw rod assembly, so that the driving force of the driving motor is transmitted to the first screw rod assembly through the first rotation transmission unit and the second rotation transmission unit, the direct 'point-to-point' connection relation between the traditional motor and the screw rod assembly is replaced by the 'surface-to-point' connection relation, the operation stability of the first screw rod assembly and the second screw rod assembly is improved, and the integral axial compactness between the driving motor and the screw rod assembly is stronger through the first rotation transmission unit and the second rotation transmission unit.

Still further, to holistic outer tube, inner tube to and well pipe and bushing structure, combine the utility model discloses a screw mechanism adopts locking screw and fastening screw to realize the connected mode between the part, compares riveted technology structure, not only is convenient for assemble, convenient to overhaul moreover and change part.

Drawings

Fig. 1 is an overall sectional view of a lifting column according to embodiment 1 of the present invention;

FIG. 2 is an enlarged view of part A of FIG. 1;

FIG. 3 is an enlarged view of portion B of FIG. 1;

fig. 4 to 9 are schematic partial structural views of the rotation transmission unit;

fig. 10 is a schematic structural view of the whole cross section of the screw structure of the lifting column according to embodiment 1 of the present invention;

FIG. 11 is an enlarged view of a portion of FIG. 10;

fig. 12 is a partially enlarged view of fig. 10.

In the figure: the device comprises an outer pipe 1, an inner pipe 2, a middle pipe 3, a bottom plate 4, a driving motor 5, a sleeve 6, a connecting block 7, a fastening screw 8, a first master gear 9, a first slave gear 10, a first gear ring 11, a first linkage plate 12, a projecting shaft 13, a second master gear 14, a second slave gear 15, a second gear ring 16, a second linkage plate 17, a first connecting shaft 18, a second connecting shaft 19, a fixing sleeve 20, a connecting sleeve 21, a connecting ring 22, a ball 23, a limiting sleeve 24, an annular groove 25, a connecting part 26, a first lead screw 27, a screw 28, a spline sleeve 29, a second lead screw 31, a second lead screw 32, a limiting stopper 33, a bearing 40, a stand pipe 34, a first lead screw 35, a main part 351, a wing part 352, a recessed area 353, a sliding sheet 36, an isolating ring 37, an inner tooth structure 38 and a locking screw 39.

Detailed Description

In order that the present invention may be more readily and clearly understood, the following detailed description of the present invention is provided in connection with the accompanying drawings.

Referring to fig. 1 to 12, the present embodiment provides a lifting column, including: the device comprises an outer pipe 1, an inner pipe 2 nested in the outer pipe 1, a middle pipe 3 arranged in the inner pipe 2, and a screw rod mechanism arranged in the middle pipe 3; the inner tube 2, the outer tube 1 and the middle tube 3 are all arranged coaxially here. The bottom of the outer pipe 1 is fixedly connected with the bottom plate 4.

The screw rod mechanism comprises a power assembly, a first screw rod assembly connected with the power assembly, and a second screw rod assembly connected with the first screw rod assembly. The power assembly comprises a driving motor, a first rotation transmission unit connected with an output shaft of the driving motor, and a second rotation transmission unit connected with the first rotation transmission unit; the second rotation transmission unit is connected with the first screw rod assembly.

A sleeve 6 is sleeved on the outer side of the second screw rod assembly, namely the second screw rod assembly is positioned in the inner cavity of the sleeve 6; the bottom of the sleeve 6 is connected with the inner tube 2, so that the sleeve 6 drives the inner tube 2 to realize lifting movement relative to the outer tube 1 under the action of the first screw rod assembly and the second screw rod assembly.

The sleeve 6 and the inner tube 2 of the embodiment are connected in this way, and the bottom tube wall of the inner tube 2 is provided with a connecting block 7 protruding from the tube wall; the connecting block 7 is connected and fixed with the bottom of the sleeve 6 through the fastening screw 8, so that the sleeve 6 can drive the inner tube 2 to realize a synchronous motion relation with the sleeve 6, and the motion in the embodiment specifically refers to a lifting motion relative to the outer tube 1. The middle pipe 3 is positioned in the gap between the inner pipe 2 and the sleeve 6; the first rotation transmission unit and the second rotation transmission unit are arranged in the inner cavity of the middle pipe 3 and are positioned above the sleeve 6; the second screw rod assembly is arranged in the inner cavity of the sleeve 6; the first screw assembly is partially disposed in the lumen of the middle tube 3 and partially inserted in the cannula 6.

Specifically, the first rotation transmission unit adopted in this embodiment includes a first master gear 9 fixedly connected to the output shaft of the driving motor, three first slave gears 10 arranged at intervals and respectively meshed with the first master gear 9, and a first gear ring 11 sleeved outside the three first slave gears 10 and simultaneously meshed with the three first slave gears 10. In the process of operation of the driving motor, the first master gear 9 is driven to synchronously rotate along with the output shaft of the driving motor, at this time, due to the action of the first gear ring 11, the three first slave gears 10 rotate along the radial direction of the first gear ring 11 in the space formed by the first gear ring 11 and the first master gear 9, at this time, the three first slave gears 10 rotate along the same direction, and in this process, the first gear ring 11 is kept in a static state, that is, does not rotate.

The second rotation transmission unit comprises a first linkage plate 12 connected with the three first slave gears 10, a protruding shaft 13 integrally connected with the first linkage plate 12 and located on the end face of the linkage plate, which is far away from the first slave gears 10, a second master gear 14 fixedly connected with the protruding shaft 13, three second slave gears 15 which are arranged at intervals and meshed with the second master gear 14 respectively, and a second gear ring 16 which is sleeved on the outer sides of the three second slave gears 15 and meshed with the three second slave gears 15 simultaneously. Because the first linkage plate 12 is connected to the three first slave gears 10 at the same time, when the three first slave gears 10 rotate in the same direction, the first linkage plate 12 is driven to rotate synchronously, at this time, under the rotation action of the first linkage plate 12, the second master gear 14 rotates, and in combination with the action of the second ring gear 16, the three second slave gears 15 rotate in the space formed by the second ring gear 16 and the second master gear 14 along the radial direction of the second ring gear 16, and at this time, the three second slave gears 15 rotate in the same direction, and in this process, the second ring gear 16 is kept in a stationary state, that is, does not rotate.

Since the second linkage plate 17 is simultaneously connected to the three second slave gears 15, the three second slave gears 15 rotate in the same direction, and the second linkage plate 17 is driven to rotate synchronously, and since the engagement portion 26 is integrally formed with the second linkage plate 17, the engagement portion 26 also generates a linkage effect with the second linkage plate 17. At this time, the rotational power of the driving motor is transmitted to the joint portion 26 through the first and second rotation transmission units, so that the joint portion 26 is connected to the first lead screw 27 assembly to generate a driving force for the first lead screw 27 assembly.

Optionally, a first gap exists between the first main gear 9 and the first linkage plate 12; and a second gap exists between the second main gear 14 and the second linkage plate 17. In this way, the first linkage plate 12 is caused to generate rotary power solely by the action of the first slave gear 10, and the second linkage plate 17 is caused to generate rotary power solely by the action of the second slave gear 15.

Wherein, the three first slave gears 10 are respectively connected with the first linkage plate 12 through the first connecting shafts 18; the three second slave gears 15 are connected to the second linkage plate 17 via second connection shafts 19, respectively.

The first gear ring 11 and the second gear ring 16 are externally sleeved with a fixed sleeve 20, the fixed sleeve 20 is connected with a connecting sleeve 21 through a screw 28, the inner cavity of the connecting sleeve 21 is integrally provided with a connecting ring 22, the connecting ring 22 is provided with a through hole for an output shaft of a driving motor to pass through, the inner annular wall of the connecting ring 22 is provided with a plurality of balls 23 at intervals, a limiting sleeve 24 is externally connected to the part of the output shaft of the driving motor connected with the through hole, and the outer side wall of the limiting sleeve 24 is provided with an annular groove 25 suitable for being matched with the balls 23. The output shaft of the driving motor drives the stop collar 24 to rotate synchronously, and along with the rotation of the stop collar 24, the stop collar 24 can rotate smoothly relative to the connecting ring 22 due to the design of the balls 23.

More specifically, the first lead screw assembly includes a first lead screw 27 connected to the engaging portion 26, a first nut 35 sleeved on the first lead screw 27, and a spline housing 29 connected to an end portion of the first lead screw 27 far from the engaging portion 26 through a screw 28. The first nut 35 is fixedly connected to an axial end of the sleeve 6 by a locking screw 39.

The second screw rod assembly comprises a second screw rod 31 arranged on the circumferential outer side of the first screw rod 27 and a second screw nut 32 sleeved on the second screw rod 31; the inner side wall of the second screw rod 31 is provided with an inner tooth structure 38 which is suitable for being matched and nested with the spline housing 29. Specifically, under the rotation action of the output shaft of the driving motor, the first lead screw 27 rotates, and due to the matching and matching action of the spline housing 29 and the internal tooth structure 38 on the inner side wall of the second lead screw 31, the second lead screw 31 can synchronously rotate along with the first lead screw 27. The second screw rod 31 is connected with the first screw rod 27 through the spline sleeve 29, compared with a single screw rod in the prior art, the connection mode of the first screw rod 27 and the second screw rod 31 is that the first screw rod 27 prolongs the axial length of the second screw rod 31, and the first screw rod 27 can also ensure that the rotation of the second screw rod 31 is subjected to the relative fixing acting force in the radial direction of the first screw rod 27 so as to effectively ensure the stability of the second screw rod 31 in the rotation process, and the structure ensures that the stability of the second screw rod 31 in the rotation process can be ensured even if a bearing is not arranged at the end part of the second screw rod 31 far away from the driving motor.

The first screw 35 includes a base 351 sleeved with the first screw 27, and a wing 352 integrally formed on the outer side of the base 351 and having an annular structure; a recessed region 353 having an annular structure is formed between the body 351 and the wing 352; the end of the second lead screw 31 is inserted into the recess 353 and connected to the wing 352; the end of the second screw 31 is connected to the side end of the wing portion 352 facing the base portion 351 via a bearing 40. That is, in the process that the second lead screw 31 rotates along with the first lead screw 27, the second lead screw 31 can rotate smoothly relative to the first nut 35, so that the second lead screw 31 can move up and down along with the first nut 35 relative to the axial direction of the second nut 32.

The first screw 35 includes a base 351 sleeved with the first screw 27, and a wing 352 integrally formed on the outer side of the base 351 and having an annular structure; a recessed region 353 having an annular structure is formed between the body 351 and the wing 352; the end of the second lead screw 31 is inserted into the recess 353 and connected to the wing 352; the end of the second screw 31 is connected to the side end of the wing portion 352 facing the base portion 351 via a bearing 40. That is, in the process that the second lead screw 31 rotates along with the first lead screw 27, the second lead screw 31 can rotate smoothly relative to the first nut 35, so that the second lead screw 31 can move up and down along with the first nut 35 relative to the axial direction of the second nut 32. Compared with a single screw rod in the prior art, the first screw rod 27 and the second screw rod 31 are combined to extend the axial length of the single screw rod, the first screw rod 27 and the second screw rod 31 can effectively ensure the stability of the second screw rod 31 in the rotating process due to the fact that the first screw rod 27 enables the rotation of the second screw rod 31 to be subjected to the relative supporting acting force in the radial direction of the first screw rod 27, and the structure enables the end, away from the first recruitment, of the second screw rod 31 to be ensured to also ensure the stability of the rotation of the second screw rod 31 even if no bearing is arranged.

Since the inner tube 2 of the present embodiment needs to move up and down relative to the outer tube 1, if the inner tube 2 is tightly attached to the inner sidewall of the outer tube 1, a large resistance will be generated during the up and down movement of the inner tube 2, and therefore, a plurality of sliding pieces 36 protruding from the sidewall of the inner tube 2 are disposed at intervals on the sidewall of the inner tube 2 facing the external appearance; the sliding piece 36 abuts against the inner tube 2 wall of the outer tube 1. The sliding sheet 36 at this time can realize the radial supporting function between the outer tube 1 and the inner tube 2, and can also avoid the too large resistance of the inner tube 2 in the lifting movement relative to the outer tube 1, and for the sliding sheet 36 at this position, the end surface of the sliding sheet 36 contacting the inner side wall of the outer tube 1 can be set as a smooth surface, so as to reduce the friction force between the inner tube 2 and the outer tube 1.

For the top parts of the inner pipe 2 and the outer pipe 1 which are far away from the bottom plate 4 in the embodiment, the top parts of the inner pipe 2 and the outer pipe 1 which are far away from the bottom plate 4 are respectively provided with an annular structure isolation ring 37; the spacer ring 37 on the inner pipe 2 abuts against the outer pipe 1 wall of the middle pipe 3; spacer ring 37 on outer tube 1 abuts spacer ring 37 on inner tube 2. The spacer ring 37 can play a role in radially supporting the inner tube 2 and the outer tube 1, and can also play a role in blocking foreign matters outside the inner tube 2 and the outer tube 1, so that the foreign matters outside the inner tube 2 and the outer tube 1 are difficult to enter the inner tube 2 and the outer tube 1 through the tops of the inner tube 2 and the outer tube 1.

The specific implementation manner of the lifting column of this embodiment is as follows:

under the rotation power of the output shaft of the driving motor, under the action of the first rotation transmission unit and the second rotation transmission unit, the first screw rod 27 generates rotation action, due to the action of the spline sleeve 29 between the first screw rod 27 and the second screw rod 31, the second screw rod 31 generates rotation action synchronous with the first screw rod 27, the first screw nut 35 drives the sleeve 6 to move axially under the rotation action of the first screw rod 27, at the moment, the second screw nut 32 is fixedly connected with the vertical pipe 34, the vertical pipe 34 is fixedly connected with the bottom plate 4, so that the second screw nut is in a static and motionless state relative to the bottom plate 4, and in combination with the rotation of the second screw rod 31, in this way, the rotation of the second screw rod 31 can generate lifting motion relative to the second screw nut 32, because the top of the second screw rod 31 is connected with the first screw nut 35, the sleeve 6 finally generates lifting motion relative to the vertical pipe 34 under the synergistic action of the first screw rod 27 and the second screw rod 31, the sleeve 6 is connected with the inner pipe 2 through the connecting block 7, so that the sleeve 6 and the inner pipe 2 are lifted in a linkage manner, at the moment, the inner pipe 2 is lifted relative to the outer pipe 1, and the stand pipe 34 and the outer pipe 1 are in a static state relative to the bottom plate 4. For example, when the top of the inner tube 2 of the present embodiment is connected to the bottom of the table top, the outer tube 1 plays a role of table legs with respect to the table top, and the lifting of the inner tube 2 with respect to the outer tube 1 causes the lifting of the inner tube 2 to drive the height of the table top with respect to the table legs to be adjusted.

The above embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be understood that the above embodiments are only examples of the present invention, and are not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

In the description of the present invention, it is to be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the equipment or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. 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 description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the present disclosure, unless otherwise expressly stated or limited, the first feature may comprise both the first and second features directly contacting each other, and also may comprise the first and second features not being directly contacting each other but being in contact with each other by means of further features between them. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.

Claims

1. A lifting column, comprising: the screw rod mechanism comprises an outer pipe, an inner pipe nested in the outer pipe, a middle pipe arranged in the inner pipe, and a screw rod mechanism arranged in the middle pipe;

the bottom of the outer pipe is fixedly connected with the bottom plate;

2. The lifting column according to claim 1, wherein a spline housing is fixedly connected to an end of the first lead screw, which is far away from the first nut, through a screw; and

3. The lifting column according to claim 2, wherein the first nut comprises a base portion sleeved with the first lead screw, and a wing portion of an annular structure integrally arranged on the outer side of the base portion; a concave area with an annular structure is formed between the main part and the wing part;

4. The lifting column according to claim 3, wherein a limit stop is sleeved on the outer side of the end of the second screw rod far away from the end connected with the first screw nut; the second screw rod is suitable for rotating relative to the limit stop;

5. The lifting column according to any one of claims 1 to 4, wherein the first screw rod is connected with a power assembly to enable the power assembly to drive the first screw rod to rotate;

6. The lifting column according to claim 5, wherein the bottom tube wall of the inner tube is provided with a connecting block;

7. The lifting column according to claim 6, wherein the first rotation transmission unit comprises a first master gear fixedly connected to the output shaft of the driving motor, three first slave gears spaced apart from each other and engaged with the first master gear, and a first gear ring sleeved outside the three first slave gears and simultaneously engaged with the three first slave gears;

8. The lifting column of claim 7, wherein there is a first gap between the first main gear and the first linkage plate; and

a second gap exists between the second main gear and the second linkage plate.

9. The lifting column as claimed in claim 1, wherein a plurality of sliding pieces protruding from the side wall of the inner tube are provided at intervals on the side wall of the inner tube facing the outer appearance; the sliding sheet is abutted against the inner pipe wall of the outer pipe.

10. The lifting column according to claim 1, wherein a ring-shaped structure isolation ring is respectively arranged on the top parts of the inner pipe and the outer pipe, which are far away from the bottom plate;

the spacer ring on the outer tube abuts the inner tube spacer ring.