CN104863937B - Casing assembly structure and lifting column - Google Patents

Abstract

The invention discloses a sleeve assembly structure which is convenient for assembly, which comprises a first sleeve, a second sleeve, a first slider and a second slider, the second sleeve is sleeved in the first sleeve, the first sleeve There is a distance between the inner wall of the tube and the outer wall of the second sleeve, the first slider is sleeved on the second sleeve, the first sleeve is fixedly connected with the first slider, and the second slider is set on the first sleeve Between the second sleeve and the second sleeve, the second slider is fixed relative to the axial direction of the second sleeve, the second slider is slidably matched with the first sleeve, the inner wall of the first sleeve is provided with grooves, and the first slider is provided with There is a connecting part, the connecting part is provided with a clamping part that is inserted into the groove, and the side of the clamping part facing the first sleeve has an inclined surface; the outer wall of the second sleeve is provided with a hole structure, and the first slide After the block slides to the slot structure along the second sleeve, all the connecting parts correspond to the positions of the slot structure; the invention also discloses a lifting column adopting the sleeve structure.

Description

Casing assembly structure and lifting column

technical field

The invention relates to a lifting column, in particular to a casing assembly structure and a lifting column adopting the casing assembly structure.

Background technique

Lifting columns are widely used on height-adjustable items such as beds, chairs, and tables. The main function is to move the load in a straight line through its own expansion and contraction.

Existing lifting columns generally have a number of mutually nested sleeves, and the lifting column drives the sleeves to move with each other through the transmission device to realize the expansion and contraction of the lifting column. For example, the Chinese patent with the publication number CN104254264A discloses a raised column which is preferably used for a height-adjustable table. The raised column is mainly composed of a guide, a spindle unit and a motor unit. , the second part, and the third part are made up of three parts nested on each other. The motor unit mainly provides power, and the spindle unit (equivalent to the transmission device) connects the guide and the motor unit to transmit the power of the motor unit to the guide. And then realize the expansion and contraction of the driving guide. And authorized notification number is that the Chinese patent of CN203095510U discloses a kind of lifting column, and the guide member of this lifting column is then formed by two parts nesting of outer tube and inner tube. However, no matter whether it is formed by nesting two parts or three or more parts are nested with each other, friction will inevitably be generated when two adjacent parts slide relative to each other. In order to reduce friction, it is necessary to set a slider between two adjacent components so that the two adjacent components can slide relative to each other.

In the prior art, two groups of sliders are generally arranged between two adjacent parts, one group of sliders is fixedly connected with the outer parts, the other group of sliders is fixedly connected with the inner parts, and the sliders are fixedly connected with the outer parts. The fixed connection method generally adopts punching holes on the parts, which causes holes to appear on the outer parts and affects the appearance. And because the bottom of the lifting column generally needs to install the base, so that the transmission device and the motor unit are installed on the base, and one end of the inner parts is fixed on the base, so that when one end of the inner parts is installed with a base, and the other end side wall is installed with a slide After the block, there is a problem that the external parts are difficult to install.

In addition, in the existing lifting columns, the transmission device and the motor unit (usually a motor) are generally connected by a worm gear to transmit power. The fixing method of the motor unit has technical problems such as high cost, complicated structure, and inconvenient assembly. .

Contents of the invention

The technical problem to be solved by the present invention is to provide a casing assembly structure that is convenient for assembly.

Another object of the present invention is to provide a lifting column adopting the sleeve assembly structure.

In order to solve the above-mentioned existing technical problems, the present invention adopts the following scheme: the sleeve assembly structure includes a first sleeve, a second sleeve, a first slider and a second slider, and the second sleeve is sleeved on the In the first sleeve, there is a distance between the inner wall of the first sleeve and the outer wall of the second sleeve, the first slider is an annular structure, and the first slider is sleeved on the second sleeve And can reciprocate and slide axially along the second sleeve, the first sleeve is fixedly connected with the first slider, the second slider is arranged between the first sleeve and the second sleeve, the second The slider is fixed axially relative to the second sleeve, the second slider is slidingly fitted with the first sleeve, the inner wall of the first sleeve is provided with a groove, and the first slider faces the second slider One side of the first sleeve is provided with a connecting portion extending to the position of the groove along the axial direction of the first sleeve, and the connecting portion is provided with a locking portion that is inserted into the groove, and the first slider passes through The clamping part snaps into the groove to realize the fixed connection with the first sleeve; the side of the clamping part facing the first sleeve has an inclined surface, or there is a gap between the inner wall surface of one end of the first sleeve and the end face. An inclined surface is provided, and the distance from the inclined surface to the second sleeve gradually increases in the direction from the connecting part to the first slider along the axial direction of the first sleeve; on the outer wall of the second sleeve A hole structure is provided, and when the first slider is located at the hole structure, the connecting portion corresponds to the position of the hole structure.

In the present invention, when the first slider is located at the slot structure and the connecting portion corresponds to the slot structure, the connecting portion can bend into the slot structure under the action of an external force. When assembling the casing structure: first install the first slider and the second slider on the second casing, so that the position of the connecting part on the first slider corresponds to the position of the hole structure on the second casing , and then put the first bushing on the second bushing and the inserting end of the first bushing and the connecting part are located on the same side of the first slider, and then move the first bushing relative to the second bushing , moving the first sleeve to the position of the first slider so that the connecting portion on the connecting portion enters into the first sleeve and finally the locking portion on the connecting portion snaps into the hole structure.

Preferably, the hole structure is a plurality of installation holes provided on the side wall of the second casing, the number of the installation holes is equal to the number of the connection parts, and the positions of the installation holes correspond to the positions of the connection parts one by one .

Preferably, the groove is an annular groove surrounding the inner wall of the first sleeve.

Preferably, the second slider is a plurality of elongated sliders distributed around the second sleeve, and the second sleeve is provided with an insertion hole at a position corresponding to each elongated slider , the elongated slider is provided with an insertion column extending into the socket.

At the same time, the present invention also provides a lifting column, including a base, a guide is installed on the base, the guide is formed by at least two bushings, and the guide passes between adjacent bushings. Relative sliding to realize expansion and contraction, the transmission device for driving the guide to expand and contract is installed on the base, and the aforementioned sleeve structure is used between at least two adjacent sleeves in the guide.

Preferably, the sleeve structure is composed of an inner tube, a middle tube and an outer tube, the inner tube is fixedly connected to the base, the middle tube is sleeved outside the inner tube, and the outer tube is sleeved outside the middle tube, Between the middle pipe and the inner pipe and between the outer pipe and the middle pipe, the above-mentioned casing structure is adopted.

Preferably, the transmission device includes a worm gear and a motor arranged in the base, the output end of the motor is provided with a worm, and the worm engages with the worm gear, the base includes a bottom box and a bottom cover, and the motor is placed on the bottom In the box, limit blocks are provided on the bottom cover corresponding to both sides of the motor, the bottom cover is connected to the bottom box, and the limit blocks laterally limit the motor.

Preferably, an elastic pad is provided on the limit block, and the elastic pad is closely attached to the side of the motor.

Preferably, the elastic pad is provided with a groove, and the limiting block is inserted into the groove to fix the elastic pad.

Preferably, the side wall of the bottom cover is provided with a tenon, the side wall of the bottom box is provided with a positioning hole, the tenon is fastened into the positioning hole to position the bottom cover, the upper part of the tenon is provided with a slope, the The front end of the motor is provided with an auxiliary pressing block, and the bottom cover presses the front end of the motor through the auxiliary pressing block.

Beneficial effect:

After the above-mentioned technical scheme is adopted in the present invention, the first slider can be fixedly connected to the first sleeve by snapping into the groove on the inner wall of the first sleeve through the clamping portion on the connecting portion, without needing to punch the first sleeve on the side wall of the first sleeve. holes to realize the fixing of the first slider and the first casing; by setting the hole structure on the outer wall of the second casing, the assembly of the casing structure is realized through the cooperation of the hole structure and the connecting part, even at the upper end of the second casing It can also be assembled conveniently and quickly when installing other components.

Description of drawings

Fig. 1 is a schematic structural view of the connection between the first sleeve and the first slider in Embodiment 1 of the present invention;

Fig. 2 is a schematic diagram of the local structure of the first casing in Embodiment 1 of the present invention;

3 is a schematic structural view of the first slider in Embodiment 1 of the present invention;

Fig. 4 is a schematic structural view of the connection between the second bushing and the second slider in Embodiment 1 of the present invention;

Fig. 5 is a schematic structural diagram of a second casing in Embodiment 1 of the present invention;

6 is a schematic structural diagram of a second slider in Embodiment 1 of the present invention;

Fig. 7 is a schematic structural view of the sleeve structure in the first embodiment of the present invention when assembled;

Fig. 8 is a partial cross-sectional view I of the casing structure in the first embodiment of the present invention during assembly;

Fig. 9 is a partial cross-sectional view II of the casing structure in the first embodiment of the present invention during assembly;

Fig. 10 is a partial cross-sectional view III of the casing structure in the first embodiment of the present invention during assembly;

Fig. 11 is a partial cross-sectional view of the sleeve structure in the second embodiment of the present invention during assembly;

Fig. 12 is a cross-sectional view of the lifting column in the third embodiment of the present invention;

Fig. 13 is a partial explosion structure diagram in Embodiment 3 of the present invention;

Fig. 14 is a bottom view of the base in Embodiment 3 of the present invention;

Fig. 15 is A-A sectional view of Fig. 14;

Fig. 16 is a schematic diagram of the cooperation structure of the motor and the bottom cover in the present invention;

FIG. 17 is an enlarged view at B in FIG. 16 .

detailed description

Embodiment one:

As shown in Figures 1 to 7, it is a preferred embodiment of the sleeve assembly structure of the present invention. The sleeve structure includes a first sleeve 21, a second sleeve 22, a first slider 23 and a second slider. The first sleeve 21 and the second casing 22 are both straight pipe structures and circular pipe structures. The first slider 23 is a ring-shaped structure, and the second slider is four elongated sliders 24. The casing structure is particularly It is applicable to the situation that another component is installed at one end of the second sleeve, and the first sliding block 23 is located between the component and the second sliding block.

The second sleeve 22 is sleeved in the first sleeve 21, and there is a distance between the inner wall of the first sleeve 21 and the outer wall of the second sleeve 22, and the first slider 23 is also sleeved in the second sleeve 22 Above, the first slider 23 is fixed at one end of the first sleeve 21, the inner wall of the first sleeve 21 is provided with a groove 211 at the end, and the first slider 23 is provided on one side facing the first sleeve 21. There are four connecting parts 231 extending to the inside of the first sleeve 21 along the axial direction of the first sleeve 21, the four connecting parts 231 are on the first slider 23, and each connecting part 231 extends to the first At the position where the inner groove 211 of the sleeve 21 is located, and the connecting portion 231 is provided with a locking portion 232 that is inserted into the groove 211 at this position, and the first slider 23 is realized by locking into the groove 211 through the locking portion 232 It is fixedly connected with the first sleeve 21.

Four elongated sliders 24 are fixed on the outer wall of one end of the second sleeve 22, and the four elongated sliders 24 are symmetrically distributed around the second sleeve 22. On the second sleeve 22, corresponding Each elongated slider 24 is provided with a socket 222 at the position, and the elongated slider 24 is provided with an insertion post 241 extending into the socket 222, and the elongated slider 24 passes through the insertion post 241 It is inserted into the insertion hole 222 to realize fixed installation on the second sleeve 22 . When the first sleeve 21 is sleeved on the second sleeve 22, four elongated sliders 24 are located between the first sleeve 21 and the second sleeve 22, and the outer surface of each elongated slider 24 There are protruding sliding bars 242 on each of the inner walls of the first sleeve 21, and each of the inner walls of the first sleeve 21 is provided with a slide groove 212 extending axially along the first sleeve 21 and passing through both ends of the first sleeve 21. The slide block 24 is slidably matched with the first sleeve 21 through the cooperation of the slide bar 242 and the chute 212. When the first sleeve 21 moves axially relative to the second sleeve 22, the slide bar 242 slides relative to the chute 212; and the first The extending direction of the connecting portion 231 on the slider 23 is toward the positions of the four elongated sliders 24 .

In this embodiment, the locking portion 232 has an inclined surface 233 on the side facing the inner wall of the first sleeve 21. When the first sleeve 21 is placed on the second sleeve 22, the inclined surface 233 is located near the connecting portion 231. One end of the elongated slider 24, and the distance from the inclined surface 233 to the second sleeve 22 in the direction from the elongated slider 24 to the first slider 23 along the axial direction of the first sleeve 21 gradually increases, and the minimum distance L _min from the inclined surface 233 to the second sleeve 22 is smaller than the distance D between the inner wall of the first sleeve 21 and the outer wall of the second sleeve 22, and the maximum distance L _max is greater than that of the first sleeve 21 The distance D between the inner wall and the outer wall of the second sleeve 22 . The outer wall of the second sleeve 22 is provided with a slot structure. In this embodiment, the slot structure is four installation holes 221 arranged on the side wall of the second sleeve 22. The distribution positions of the four installation holes 221 and the four The distribution positions of the four connecting parts 231 are corresponding, that is, when the first slider 23 moves to the position of the hole structure, the four connecting parts 231, especially the locking parts 232 on the four connecting parts 231 are exactly opposite to the four connecting parts 231. Mounting holes 221 .

When the casing structure is assembled, the first slider 23 and the second slider are first installed on the second casing 22, so that the first slider 23 on the connecting portion 231, especially on the four connecting portions 231 The position of the part 232 corresponds to the four installation holes 221 on the second sleeve 22; then the first sleeve 21 is placed on the second sleeve 22 from the end where the second slider of the second sleeve 22 is located, At this time, the inserting end of the first sleeve and the connecting portion 231 are located on the same side of the first slider 23; then the first sleeve 21 is moved to make it approach the position of the first slider 23. As shown in Figures 7 and 8, a part of the inclined surface 233 on the connection part 231 enters in the first sleeve pipe 21; The active force of the first sleeve 21 bends down into the four mounting holes 221, and because the four connecting portions 231 bend into the four mounting holes 221, when the first sleeve 21 continues to move, the four connecting portions 231 can All of them easily enter the first sleeve 21, as shown in Figure 9, at this time, the locking part 232 is against the inner wall of the first sleeve 21; as the first sleeve 21 continues to move, when the groove 211 moves After arriving at the position of the locking portion 232 , as shown in FIG. 10 , the connecting portion 231 rebounds, and the locking portion 232 snaps into the groove 211 along the way.

In this embodiment, the groove 211 is an annular groove surrounding the inner wall of the first sleeve 21, of course, it can also be made in the form of four small grooves, and each small groove accommodates a locking portion 232; the inclined surface 233 adopts a flat surface , can also be set as an arc-shaped concave surface or an arc-shaped convex surface; the first casing 21 and the second casing 22 can be round tubes, or non-rotating tube structures such as square tubes and oval tubes.

Embodiment two:

The structure is basically the same as that of Embodiment 1. The difference from Embodiment 1 is that, as shown in FIG. 11 , the inclined surface 233 is arranged between the inner wall of one end of the first sleeve 21 and the end surface.

Embodiment three:

The lifting column includes a base 1. A guide is installed on the base 1. The guide is formed by connecting at least two sleeves. The guide realizes expansion and contraction through relative sliding between adjacent sleeves among the three sleeves. The base 1 is equipped with a transmission device for driving the telescopic guide.

In this embodiment, the guide is composed of an inner tube 25, a middle tube 26 and an outer tube 27. The inner tube 25 is fixedly installed on the base 1. In order to facilitate the firm connection between the inner tube 25 and the base 1, the inner tube and the base 1 Connected by reinforcement. The middle pipe 26 is sleeved outside the inner pipe 25, and the outer pipe 27 is sleeved outside the middle pipe 26. The connection structure between the middle pipe 26 and the inner pipe 25 and the connection structure between the outer pipe 27 and the middle pipe 26 are all as implemented. The casing assembly structure described in Example 1.

Specifically, as shown in Figure 12, in the connection structure between the middle pipe 26 and the inner pipe 25, the bottom of the middle pipe 26 is provided with a round slider 29, and the top outer wall of the inner pipe 25 is provided with 4 long sliders 28, the inner pipe 25 is equivalent to the second sleeve pipe in the first embodiment, the middle pipe 26 is equivalent to the first sleeve pipe in the first embodiment, the round slider 29 is equivalent to the first slider in the first embodiment, and the long slider 28 It is equivalent to the second slider in the first embodiment, and the connection mode between the inner tube 25, the middle tube 26, the round slider 29 and the long slider 28 is the same as that of the first and second embodiments. Similarly, in the connection structure between the outer tube and the middle tube, the bottom of the outer tube 27 is also provided with a round slider 29, and the top outer wall of the middle tube 26 is provided with 4 long sliders 28, and the outer tube is equivalent to the first embodiment. and the first sleeve pipe in embodiment two, the middle pipe is equivalent to the second sleeve pipe in embodiment one and embodiment two, the round slider 29 is equivalent to the first slider in embodiment one and embodiment two, and the long slider 28 is equivalent to the second slide block in embodiment one and embodiment two, and the connection mode among outer tube 27, middle pipe 26, round slider 29, long slider 28 is also identical with embodiment one and embodiment two.

In this embodiment, the transmission device includes a motor 4 , a worm gear 6 , a first spindle 71 , a second spindle 72 , a screw 73 , a primary connector 74 , a secondary connector 75 and a tertiary connector 76 . Both the motor 4 and the worm gear 6 are located in the base 1, as shown in Figures 13 to 17, the base 1 is formed by fastening the bottom box 11 and the bottom cover 12, the motor 4 is placed in the bottom box 11, the base 1 of this embodiment Bottom box 11 has cavity 10, can accommodate motor 4; The output end of motor 4 is provided with worm screw, and worm screw meshes with worm wheel 6, and motor 4 rotates and drives worm wheel 6 to rotate, and the first mandrel 71, the second mandrel 72 are both centered. Hollow shaft, the first mandrel 71 is sleeved in the inner tube 25, the first mandrel 71 is fixedly connected with the worm gear 6, the rotation of the worm gear 6 drives the first mandrel 71 to rotate, and the second mandrel 72 is sheathed on the first mandrel 71 Inside, the inner wall of the first mandrel 71 is provided with a spline groove extending axially along the first mandrel 71, and the second mandrel 72 is provided with a spline part 721 matched with the spline groove, and the second mandrel 72 passes through the spline part. 721 cooperates with the spline groove to move axially relative to the first mandrel 71, the first-level connecting piece 74 is fixed on the first mandrel 71, and the center of the first-level connecting piece 74 is provided with a shaft hole with an internal thread, and the second mandrel 72 The outer surface is provided with external threads, the second mandrel 72 passes through the shaft hole and is threadedly matched with the first-level connector 74, the second-level connector 75 is installed on the middle tube 26, and the top of the second mandrel 72 is provided with a connecting block 722 for connecting The block 722 is positioned and installed in the secondary connector 75 and can rotate axially relative to the secondary connector 75. The connecting block 722 is provided with a threaded hole, and the screw rod 73 is sleeved in the threaded hole on the connecting block 722 to connect with the connecting block 722. threaded fit, the bottom end of the screw mandrel 73 extends into the second mandrel 72, and the top end of the screw mandrel 73 is fixedly connected with the outer tube 27 through a three-stage connector 76. In this structure, the first mandrel 71, the second mandrel 72, screw mandrel 73 coaxial.

In this embodiment, since the transmission device transmits power through the first mandrel 71, the second mandrel 72, and the screw mandrel 73 to generate rotational motion, it is conceivable that this movement will also cause the motor in the base to produce the same movement tendency. If the motor is not effectively fixed in the base, especially if the lateral direction of the motor is not restricted, the motor may rotate around the axis of the connection between the worm and worm assembly and the screw drive, so in actual work, the motor may be damaged. A left-to-right deflection is generated within the base. Therefore, in this embodiment, as shown in Figures 13 to 17, limit blocks 121 are provided on the bottom cover 12 corresponding to the two sides of the motor 4, the bottom cover 12 is connected to the bottom box 11, and the limit blocks 121 laterally limit the motor. 4. The bottom cover 12 of the base 1 is provided with a limit block 121, and the limit block 121 is used to limit the motor 4 laterally to solve the problem of motor deflection. 121, in order to avoid the hard contact between the motor and the limit block 121, the limit block 121 is provided with an elastic pad 3, the elastic pad 3 is close to the side of the motor 4, the shape of the elastic pad 3 can be adjusted according to the shape of the motor Adjustment. The arrangement of the elastic pad 3 can well protect the motor and reduce vibration noise. The elastic pad 3 can be made of rubber or silicone material. When assembling the elastic spacer 3, a groove 21 can be provided on the elastic spacer 3, and the limit block 121 can be inserted into the groove 31 to fix the elastic spacer 3, or the elastic spacer 3 can be directly injected to the limit by secondary injection molding. bit block 121 on. According to different motor types and motor installation requirements, multiple sets of limit blocks can be set along the motor axis. In this embodiment, two sets of limit blocks 121 are provided. Each set of limit blocks 121 includes two sets of limit blocks located on the left and right sides of the motor. Limiting block 121. The bottom cover 12 is made of plastic material, and the limit block 121 can be directly injection molded on the bottom cover 12. In order to improve the strength of the limit block 121, a reinforcing rib 123 can be injected on one side of the limit block 121 to prevent the limit block 121 from deforming. .

When the motor is installed, it is first put into the cavity 10 of the bottom box 11, and the operator needs to adjust the angle of the motor during the cooperation process between the output end of the motor and the transmission device of the actuator, so that the motor can cooperate reliably with the transmission device of the actuator. The bottom box 11 of this embodiment has a larger space, which is convenient for the operator to adjust the installation position of the motor. After the position is adjusted, the bottom cover 12 is covered, and the two sides of the motor 4 are limited by the stoppers 121, effectively preventing The motor produces deflection during operation, which not only reduces the difficulty of assembling the motor, but also ensures the stability of the motor during operation. In order to make the motor fixed reliably, the present embodiment also sets the auxiliary pressing block 5 at the front end of the motor 4, and the bottom cover 12 presses the front end of the motor 4 through the auxiliary pressing block 5; specifically, the front end of the motor 4 is a metal bracket 41, and the metal bracket Protruding positioning blocks are provided, corresponding positioning grooves are provided on the auxiliary pressing block 5, the auxiliary pressing block 5 is assembled on the metal bracket 41, the positioning block is inserted into the positioning groove, and the auxiliary pressing block 5 is pressed by the bottom cover 12, so that the motor 4 further fixed in the vertical direction.

The bottom box 11 and the bottom cover 12 of the base of the present embodiment adopt a floating connection. Specifically, a tenon 122 is provided on the side wall of the bottom cover 12, a positioning hole 111 is provided at a corresponding position on the side wall of the bottom box 11, and the tenon 122 is fastened to the positioning position. The bottom cover 12 is positioned in the hole 111, and the upper part of the tenon 122 is provided with an inclined surface 124. Due to the existence of the inclined surface 124, the bottom box 11 is allowed to have a certain floating gap. Offset, to avoid the motor vibration directly transmitted to the bottom box 11. The side wall of the bottom box 11 is provided with a threaded hole 110 in the flange, and the threaded hole 110 is usually used to connect the frame supporting the desktop. In the prior art, the inner space of the bottom box 11 is small, and there is a motor limit structure. Blocking, in order to avoid interference, the inner flange of the threaded hole cannot be made long, and the connection between the frame and the bottom box is not reliable. In this embodiment, the inner space of the bottom box 11 is relatively large, and there is no structural member to block it. The inner flange of the threaded hole 110 can be lengthened without worrying about interference with the structural member in the bottom box. In this way, the effective length of the thread is increased, which can Longer fixing screws are used to make the connection between the frame and the bottom box stronger. Generally speaking, the increased internal space of the bottom box is conducive to heat dissipation, and there may be a resonance cavity problem. However, with the above-mentioned threaded holes 110, there is usually no resonance cavity. In order to better solve this problem, a Targeted setting holes on the top.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, those skilled in the art should understand that the present invention includes but is not limited to the accompanying drawings and described in the above specific embodiments content. Any modifications that do not depart from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims (10)

1. The sleeve assembly structure, including the first sleeve (21), the second sleeve (22), the first slider (23) and the second slider, the first sleeve and the second sleeve are both Straight pipe structure, the second sleeve (22) is sleeved in the first sleeve (21), and there is a distance between the inner wall of the first sleeve (21) and the outer wall of the second sleeve (22) , the first slider (23) is an annular structure, the first slider (23) is sheathed on the second sleeve (22) and can slide reciprocatingly along the axial direction of the second sleeve (22), The first bushing (21) is fixedly connected with the first slider (23), the second slider is arranged between the first bushing (21) and the second bushing (22), and the second The slider is fixed in the axial direction relative to the second sleeve (22), and the second slider is slidingly matched with the first sleeve (21). It is characterized in that: the inner wall of the first sleeve (21) has a concave A groove (211), the side of the first slider (23) facing the second slider is provided with a connecting portion extending along the axial direction of the first sleeve (21) to the position of the groove (211) (231), the connecting part (231) is provided with a clamping part (232) that is clamped into the groove (211), and the first slider (23) is clamped into the groove through the clamping part (232) (211) to achieve a fixed connection with the first sleeve (21); the side of the locking part (232) facing the first sleeve (21) is provided with an inclined surface (233) or the first sleeve (21 ) is provided with an inclined surface (233) between the inner wall surface of one end and the end surface; the outer wall of the second casing (22) is provided with a hole structure, and the first slider (23) is located at the hole structure When all the connecting parts (231) correspond to the positions of the hole and groove structures. 2. The casing assembly structure according to claim 1, characterized in that: the hole structure is a plurality of installation holes (221) provided on the side wall of the second casing (22), and the installation holes (221 ) is equal to the number of connecting parts (231), and the positions of the mounting holes (221) correspond to the positions of the connecting parts (231) one by one. 3. The sleeve assembly structure according to claim 1, characterized in that: the groove (211) is an annular groove surrounding the inner wall of the first sleeve (21). 4. The bushing assembly structure according to claim 1, characterized in that: the second slider is a plurality of elongated sliders (24) distributed around the second bushing (22), and the first The two sleeves (22) are provided with sockets (222) corresponding to the positions of each elongated slider (24), and the elongated slider (24) is provided with an insertion hole (222 ) inside the post (241). 5. Lifting column, including a base (1), on which a guide is installed, the guide is formed by at least two sleeves socketed with each other, and the guide passes through the gap between adjacent sleeves. Sliding relative to achieve expansion and contraction, the base (1) is equipped with a transmission device for driving the guide to expand and contract, it is characterized in that: in the guide, at least two adjacent sleeves adopt the A casing assembly structure described above. 6. The lifting column according to claim 5, characterized in that: the guide is composed of an inner tube, a middle tube and an outer tube, the inner tube is fixedly connected to the base (1), and the middle tube is sleeved on Outside the inner pipe, the outer pipe is sleeved outside the middle pipe, and the sleeve pipe assembly according to any one of claims 1 to 4 is used between the middle pipe and the inner pipe and between the outer pipe and the middle pipe structure. 7. The lifting column according to claim 5 or 6, characterized in that: the transmission device includes a worm gear (6) and a motor (4) arranged in the base (1), and the output end of the motor (4) A worm is provided, the worm meshes with the worm gear (6), the base (1) includes a bottom box (11) and a bottom cover (12), the motor (4) is placed in the bottom box (11), the The bottom cover (12) is provided with limit blocks (121) corresponding to both sides of the motor (4), the bottom cover (12) is connected to the bottom box (11), and the limit blocks (121) limit the motor (4). 8. The lifting column according to claim 7, characterized in that: the limit block (121) is provided with an elastic pad (3), and the elastic pad (3) is closely attached to the side of the motor (4) . 9. The lifting column according to claim 8, characterized in that: the elastic pad (3) is provided with a groove (31), and the limit block (121) is inserted into the groove (31) to fix the elastic pad (3). 10. The lifting column according to claim 7, characterized in that: the side wall of the bottom cover (12) is provided with a tenon (122), and the side wall of the bottom box (11) is provided with a positioning hole (111), The tenon (122) is fastened to the positioning bottom cover (12) in the positioning hole (111), the upper part of the tenon is provided with a slope (124), and the front end of the motor is provided with an auxiliary pressure block (5). The bottom cover (12) presses the front end of the motor (4) through the auxiliary pressing block (5).