Telescopic sleeve and lifting table
By combining the fixed position component with the position adjustment component, a telescopic sleeve with unobstructed extension and support after extension was designed, which solved the problem of fixed leg length of the existing lifting adjustment table and achieved the effect of not tipping over during the lifting and lowering of the nursing bed.
Patent Information
- Application Number
- CN202423305675.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-01-27
- Estimated Expiration
- 2034-12-31
AI Technical Summary
The legs of existing height-adjustable tables are fixed in length when locked, which cannot meet the needs of certain scenarios and can easily cause the table to tip over if the dining side table is not adjusted when the nursing bed is raised.
The telescopic sleeve uses a fixed gear and a gear adjustment component. The inclined design of the slider and the slot allows for unobstructed extension and support after extension. The slider position is controlled by a handle component to adjust the length of the telescopic sleeve.
The telescopic sleeve can be extended in the locked position and provides support after extension, reducing the failure rate, conforming to usage habits, and meeting the requirement of not tipping over during the raising and lowering of the nursing bed.
Smart Images
Figure CN223830552U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of telescopic rods, specifically relating to a telescopic sleeve. This utility model also relates to a lifting table having the aforementioned telescopic sleeve. Background Technology
[0002] Currently, most height-adjustable tables and chairs use pneumatic rods as legs, adjusting height by extending and retracting the rods. However, in the locked state, the length of the pneumatic rod is fixed, which cannot meet the needs of some scenarios. For example, to help frail patients get up, hospital wards often have height-adjustable nursing beds. For convenient dining, side tables are also provided, with the tabletop suspended above the nursing bed so patients can lean against it while eating. In this scenario, caregivers may forget to adjust the side table before adjusting the nursing bed. When the bed is raised, the patient may knock over the table. If a telescopic sleeve could be used as a support leg for this side table, even if caregivers forget to adjust the side table before raising the bed, the tabletop raising would extend the support leg instead of causing the table to tip over. Utility Model Content
[0003] To solve the above-mentioned technical problems, it is necessary to provide a telescopic sleeve that is easy to extend and provides support after extension, as well as a lifting table that uses such a telescopic sleeve as a support leg.
[0004] To solve the above-mentioned technical problems, this utility model provides the following technical solution:
[0005] A telescopic sleeve includes an outer tube and an inner tube sleeved with the outer tube, the inner tube being slidable along the outer tube. The telescopic sleeve further includes a fixed stop component extending from the core of the outer tube into the core of the inner tube, and a gear adjustment assembly cooperating with the fixed stop component. The fixed stop component has several slots. The gear adjustment assembly includes a fixed seat connected to the inner tube and a slider floatingly connected to the fixed seat. The slider can engage with the several slots. The gear adjustment assembly further includes a switch assembly for adjusting the slider's position relative to the inner tube. The lateral distance of the fixed stop component allows the slider to leave the slot so that the inner tube retracts into the outer tube, or allows the slider to move into the slot to restrict the retraction of the inner tube; the opening direction of the plurality of slots is inclined toward the direction of the inner tube's extension, so that when subjected to a force toward the direction of the inner tube's retraction, the slider can be held in any slot; the travel range of the slider within the fixed seat is greater than the distance between adjacent slots on the fixed stop component; when the fixed seat moves outward with the inner tube, it drives the slider to slide into adjacent slots in sequence, so that the inner tube is not obstructed in the extension direction.
[0006] The telescopic sleeve provided by this utility model uses a combination of a fixed stop and a stop adjustment assembly to achieve unobstructed extension and support after extension. The switch assembly is used to adjust the relative position between the slider and the fixed stop. When the slider leaves the slot, the telescopic sleeve can extend or retract arbitrarily. When the slider moves into the slot, the telescopic sleeve can still extend but cannot retract. Since the slider is floatingly connected to the fixed base, the slider can move with the fixed base and move within the fixed base. Because the travel range of the slider within the fixed base is greater than the distance between adjacent slots on the fixed stop, when the switch assembly is in the locked position, the slider can slide into adjacent slots sequentially under the action of the fixed base. Because the opening of the slot is inclined towards the direction of the inner tube's extension, the slider slides smoothly into the adjacent slot in the direction of the inner tube's extension, but cannot slide into the adjacent slot in the direction of the inner tube's retraction. When subjected to a force that presses the inner tube into the outer tube, the slider abuts against the slot, that is, the gear adjustment component abuts against the fixed gear component, thereby providing support for the telescopic sleeve in the retraction direction. The telescopic sleeve provided by this utility model can be extended in the locked position and provides support after extension.
[0007] Preferably, the switch assembly includes a handle assembly connected to the inner tube, and a rope with one end connected to the slider and the other end connected to the handle assembly. The rope is located in the core of the inner tube. Pulling the handle assembly causes the rope to move the slider out of the slot and to the side of the fixed stop. Using the handle assembly as a switch to control the retraction capability of the telescopic sleeve, the adjustment method is the same as that of common pneumatic rods, which conforms to consumer usage habits, and this telescopic sleeve structure has a lower failure rate than pneumatic rods. When it is necessary to shorten the telescopic sleeve, pulling the handle assembly causes the slider to move out of the slot and to the side of the fixed stop. When the telescopic sleeve retracts to the required length, releasing the handle assembly causes the slider to slide into a nearby slot and abut against the fixed stop, restricting the retraction of the inner tube.
[0008] Preferably, the handle assembly includes a handle, a rotating rod that rotates with the handle, and a rope connector connected to the rotating rod. Both ends of the rotating rod are rotatably connected to the wall of the inner tube. The rope connector is sleeved on the rotating rod, and the rope is connected to the rope connector at a position away from the axis of the rotating rod. When the handle is pulled, the rotating rod rotates, causing the rope connector to rotate. The rope connector then moves the rope, which in turn moves the slider out of the slot. In this structure, the rope connector has a certain length, and one end of the rope moves in an arc during the rotation of the rotating rod in its original position. The direction of the slot on the fixed stop is inclined towards the direction of the inner tube's extension. The movement trajectory of the rope is close to the opening direction of the slot on the fixed stop. Furthermore, the slider can move slightly within the fixed seat, allowing the slider to be smoothly moved out of the slot by the rope.
[0009] Preferably, the handle includes two support arms connected to both ends of the rotating rod, and a handle rod connecting the two support arms as a single unit. The two support arms are respectively bolted to the ends of the rotating rod. In this structure, the handle is connected to both ends of the rotating rod, so that both ends of the rotating rod are subjected to rotational force simultaneously when the handle is pulled, making it less prone to damage. The support arms are bolted to the ends of the rotating rod, facilitating installation, removal, and adjustment.
[0010] Preferably, the rope passes through the fixed seat and connects to the slider. The gear adjustment assembly also includes a spring sleeved on the rope and abutting between the fixed seat and the slider. In this structure, the slider is floatingly connected to the fixed seat via the spring. Since the spring is sleeved on the rope, it always moves with the rope and is not easily damaged during movement. This arrangement also makes the spring easy to replace.
[0011] Preferably, the fixing base includes a first base plate covering the end of the inner tube located inside the outer tube, and a slider seat connected to the first base plate for the slider to be inserted into, with the spring abutting against the inner surface of the slider seat. In this structure, the first base plate covers the end of the inner tube, and when the rope drives the fixing base to move, the inner tube experiences more uniform force. This structure also allows the inner tube to descend lower than the outer tube, making the overall structure of the telescopic sleeve more stable.
[0012] Preferably, the slider includes a movable pin for engaging with the slot, and the fixed base has sliding grooves on both sides for the movable pin to pass through and slide between them. The slider is connected to the fixed base via the movable pin. In this structure, the movable pin, in addition to engaging with the slot, also connects the slider and the fixed base, making the movement of the gear adjustment component more stable and easier to install.
[0013] Preferably, the telescopic sleeve further includes a pulley assembly disposed between the inner tube and the outer tube. This structure, by incorporating the pulley assembly, makes the extension and retraction of the inner tube relative to the outer tube smoother.
[0014] Preferably, the inner tube is covered by a first substrate at one end inside the outer tube, and the outer tube is covered by a second substrate between the outer tube and the inner tube at the end through which the inner tube protrudes. The pulley assembly includes a first pulley group connected to the first substrate and a second pulley group connected to the second substrate.
[0015] Preferably, the first substrate has a limiting hole for the fixing stop to pass through, and the shape of the limiting hole matches the shape of the fixing stop. In this structure, the matching shape of the limiting hole and the fixing stop further stabilizes the trajectory of the inner tube relative to the outer tube.
[0016] A height-adjustable desk includes a telescopic sleeve as described above, a tabletop, and a support, wherein the telescopic sleeve is located between the tabletop and the support. Because it includes the telescopic sleeve as described above, it possesses all the beneficial technical effects brought about by the telescopic sleeve, which will not be elaborated further here. Attached Figure Description
[0017] The above and other objects, features, and advantages of this invention will become clearer through a more detailed description of the preferred embodiments shown in the accompanying drawings. The same reference numerals indicate the same parts throughout the drawings, and the drawings are not intentionally drawn to scale with actual dimensions; the focus is on illustrating the gist of this invention.
[0018] Figure 1 A schematic diagram of the overall structure of a preferred embodiment of the telescopic sleeve;
[0019] Figure 2 This is a schematic diagram of the overall structure of Embodiment 1 of the height-adjustable desk;
[0020] Figure 3 A schematic diagram showing the working relationship between the fixed gear position component, the gear adjustment component, and the switch component;
[0021] Figure 4 A schematic diagram showing the positional relationship between the slider base, slider, spring, and rope;
[0022] Figure 5 This is a schematic diagram of the overall structure of the handle assembly;
[0023] Figure 6 A schematic diagram of the overall structure of a preferred embodiment of the telescopic sleeve (outer tube not shown);
[0024] Figure 7 This is a schematic diagram of the overall structure of Embodiment 2 of the height-adjustable table.
[0025] In the diagram: outer tube 1, inner tube 2, fixed gear part 3, slot 31, gear adjustment assembly 4, fixed seat 41, first base plate 411, slider seat 412, slider 42, movable pin 421, spring 43, switch assembly 5, handle assembly 51, rotating rod 511, rope connector 512, handle 513, support arm 5131, handle bar 5132, rope 52, pulley assembly 6, first pulley group 61, second pulley group 62, second base plate 7, table 8, support 9. Detailed Implementation
[0026] To facilitate understanding of this utility model, a more comprehensive description of this utility model will be given below with reference to the accompanying drawings.
[0027] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to and integrated with the other element, or there may be an intervening element present. The terms "mounted," "one end," "the other end," and similar expressions used herein are for illustrative purposes only.
[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0029] refer to Figure 1 and Figure 3 The present invention discloses a telescopic sleeve, comprising an outer tube 1 and an inner tube 2 sleeved with the outer tube 1, the inner tube 2 being slidable along the outer tube 1. The telescopic sleeve further includes a fixed stop 3 extending from the center of the outer tube 1 into the center of the inner tube 2, and a stop adjustment assembly 4 cooperating with the fixed stop 3. The fixed stop 3 is provided with a plurality of slots 31. The stop adjustment assembly 4 includes a fixed seat 41 connected to the inner tube 2, and a slider 42 floatingly connected to the fixed seat 41. The slider 42 can engage with the plurality of slots 31. The stop adjustment assembly 4 also includes a switch assembly 5, the switch assembly 5 being used to adjust the slider 42 and... The lateral distance of the fixed stop 3 allows the slider 42 to leave the slot 31 so that the inner tube 2 can retract into the outer tube 1, or allows the slider 42 to move into the slot 31 to restrict the retraction of the inner tube 2; the opening direction of the plurality of slots 31 is inclined toward the direction of the inner tube 2's extension, so that when subjected to a force toward the direction of the inner tube 2's retraction, the slider 42 can be held in any slot 31; the travel range of the slider 42 within the fixed seat 41 is greater than the distance between adjacent slots 31 on the fixed stop 3; when the fixed seat 41 moves outward with the inner tube 2, it drives the slider 42 to slide into adjacent slots 31 in sequence, so that the inner tube 2 is not obstructed in the extension direction.
[0030] In the telescopic sleeve provided by this utility model, the cooperation of the fixed stop component 3 and the stop adjustment component 4 is used to achieve unobstructed extension and support after extension. The switch component 5 is used to adjust the relative position between the slider 42 and the fixed stop component 3. When the slider 42 leaves the slot 31, the telescopic sleeve can extend and retract arbitrarily. When the slider 42 moves into the slot 31, the telescopic sleeve can still extend but cannot retract. Since the slider 42 is floatingly connected to the fixed base 41, the slider 42 can move with the fixed base 41 and move within the fixed base 41. Since the travel range of the slider 42 within the fixed base 41 is greater than the distance between adjacent slots 31 on the fixed stop component 3, when the switch component 5 is in the locked position, the slider 42 can slide into adjacent slots 31 in sequence under the action of the fixed base 41. Because the opening direction of the slot 31 is inclined towards the direction of the inner tube 2's extension, the slider 42 slides smoothly into the adjacent slot 31 located in the direction of the inner tube 2's extension, but cannot slide into the adjacent slot 31 located in the direction of the inner tube 2's retraction. When subjected to a force that presses the inner tube 2 into the outer tube 1, the slider 42 abuts against the slot 31, that is, the gear adjustment component 4 abuts against the fixed gear component 3, thereby providing support for the telescopic sleeve in the retraction direction. The telescopic sleeve provided by this utility model can be extended in the locked position and provides support after being extended.
[0031] refer to Figure 3 In the preferred embodiment, the fixed stop 3 is ruler-shaped, with a plurality of slots 31 evenly spaced along one side of its long side. In other embodiments, the fixed stop 3 can also be other shapes, such as rod-shaped, and the slots 31 can also be any other shape, determined according to the shape of the slider 42, as long as they can match the shape of the slider 42. In the preferred embodiment, both the outer tube 1 and the inner tube 2 are rectangular tubes, which restricts the rotation of the inner tube 2 relative to the outer tube 1. In other embodiments, they can also be round tubes. In the preferred embodiment, the floating connection between the slider 42 and the fixed support 9 is achieved by a helical spring 43 abutting against the inner wall of the slider 42 and the fixed support 9. In other embodiments, other elastic elements such as spring sheets can also be used. In the preferred embodiment, the switch assembly 5 includes a rope 52 and a handle 513. By pulling the handle 513, the relative position of the slider 42 and the fixed stop member 3 can be adjusted. In other embodiments, a button, lever, or other switch design can be used. Alternatively, the rope 52 can be omitted and other connection methods can be used. With the help of slots cut in the tube to connect the inside and outside, the switch assembly 5 can drive the slider 42 to move into or out of the slot 31.
[0032] refer to Figure 3In a preferred embodiment, the switch assembly 5 includes a handle assembly 51 connected to the inner tube 2, and a rope 52 with one end connected to the slider 42 and the other end connected to the handle assembly 51. The rope 52 is located in the center of the inner tube 2. Pulling the handle assembly 51 causes the rope 52 to move the slider 42 out of the slot 31 and to the side of the fixed stop 3. Using the handle assembly 51 as a switch to control the retraction capability of the telescopic sleeve, the adjustment method is the same as that of common pneumatic rods, which conforms to the user habits of consumers. Moreover, this telescopic sleeve structure has a lower failure rate than pneumatic rods. When it is necessary to shorten the telescopic sleeve, pulling the handle assembly 51 will cause the slider 42 to move out of the slot 31 and to the side of the fixed stop 3. When the telescopic sleeve retracts to the required length, releasing the handle assembly allows the slider 42 to slide into the nearby slot 31 and abut against the fixed stop 3, restricting the retraction of the inner tube 2. Since the handle assembly 51 is relatively far from the slider 42, the rope 52 is easy to connect and not easily damaged. In the preferred embodiment, the rope 52 is a steel wire rope.
[0033] refer to Figures 3-5 In a preferred embodiment, the handle assembly 51 includes a handle 513, a rotating rod 511 that rotates with the handle 513, and a rope connector 512 connected to the rotating rod 511. The two ends of the rotating rod 511 are rotatably connected to the wall of the inner tube 2. The rope connector 512 is sleeved on the rotating rod 511. The rope 52 is connected to the rope connector 512 at a position away from the axis of the rotating rod 511. When the rotating rod 511 pulls the handle 513, the rotating rod 511 rotates, the rotating rod 511 drives the rope connector 512 to rotate, the rope connector 512 drives the rope 52 to move, and the rope 52 drives the slider 42 to move out of the slot 31. In this structure, the rope connector 512 has a certain length. One end of the connecting rope 52 moves in an arc during the rotation of the rotating rod 511 in its original position. The direction of the slot 31 on the fixed stop 3 is inclined towards the direction of the inner tube 2. The movement trajectory of the rope 52 is close to the opening direction of the slot 31 on the fixed stop 3. In addition, the slider 42 can move slightly within the fixed seat 41, and the slider 42 can be smoothly moved out of the slot 31 by the rope 52. In the preferred embodiment, the cross-section of the rotating rod 511 is polygonal. The rope connector 512 is sleeved on the rotating rod 511 and rotates with the rotating rod 511. The sleeved method facilitates the replacement of the rope connector 512 and makes repair easy. In the preferred embodiment, the handle 513 is connected to both ends of the rotating rod 511. In other embodiments, only a single-sided handle 513 can be provided, which can drive the rotating rod 511 to rotate.
[0034] refer to Figure 5In a preferred embodiment, the handle 513 includes two support arms 5131 respectively connected to both ends of the rotating rod 511, and a handle 5132 connecting the two support arms 5131 into one piece. The two support arms 5131 are respectively bolted to the ends of the rotating rod 511. In this structure, the handle 513 is connected to both ends of the rotating rod 511, and when the handle 513 is pulled, both ends of the rotating rod 511 are simultaneously subjected to rotational force, making it less prone to damage. The support arms 5131 are bolted to the ends of the rotating rod 511, facilitating installation, removal, and adjustment.
[0035] refer to Figure 4 In a preferred embodiment, the rope 52 passes through the fixed seat 41 and connects to the slider 42. The gear adjustment assembly 4 also includes a spring 43 sleeved on the rope 52 and abutting between the fixed seat 41 and the slider 42. In this structure, the slider 42 is floatingly connected to the fixed seat 41 by the spring 43. Since the spring 43 is sleeved on the rope 52, it always moves with the rope 52 and is not easily damaged during movement. This arrangement also makes the spring 43 easy to replace.
[0036] refer to Figure 3 , Figure 4 and Figure 6 In a preferred embodiment, the fixing base 41 includes a first base plate 411 covering one end of the inner tube 2 located inside the outer tube 1, and a slider seat 412 connected to the first base plate 411 for the slider 42 to be inserted into. The spring 43 abuts against the inner surface of the slider seat 412. In this structure, the first base plate 411 covers the end of the inner tube 2. When the rope 52 moves the fixing base 41, the inner tube 2 is subjected to relatively uniform force. This structure also allows the inner tube 2 to descend lower than the outer tube 1, making the overall structure of the telescopic sleeve more stable.
[0037] refer to Figure 4 In a preferred embodiment, the slider 42 includes a movable pin 421 for engaging with the slot 31. The fixed base 41 has sliding grooves on both sides for the movable pin 421 to pass through and slide between. The slider 42 is connected to the fixed base 41 via the movable pin 421. In this structure, the movable pin 421, besides engaging with the slot 31, also connects the slider 42 and the fixed base 41, making the movement of the gear adjustment component more stable and easier to install. In other embodiments, the movable pin 421 may be omitted; it is sufficient to restrict the slider 42 to the fixed base 41 and allow it to slide between the slots 31.
[0038] refer to Figure 6In a preferred embodiment, the telescopic sleeve further includes a pulley assembly 6 disposed between the inner tube 2 and the outer tube 1. This structure, by providing the pulley assembly 6, makes the extension and retraction of the inner tube 2 relative to the outer tube 1 smoother. In the preferred embodiment, the pulley assembly 6 includes one set disposed at the end of the inner tube 2 and one set disposed at the end of the outer tube 1. In other embodiments, the position and number of pulley assemblies 6 can vary, as long as the extension and retraction of the inner tube 2 relative to the outer tube 1 is smooth and stable.
[0039] refer to Figure 6 In a preferred embodiment, the inner tube 2, located inside the outer tube 1, is covered by a first substrate 411. The outer tube 1, with the inner tube 2 extending through it, is covered by a second substrate 7 between the outer tube 1 and the inner tube 2. The pulley assembly 6 includes a first pulley group 61 connected to the first substrate 411 and a second pulley group 62 connected to the second substrate 7. In the preferred embodiment, each of the first pulley group 61 and the second pulley group 62 includes two pulleys respectively disposed on both sides of the short side of the tube body, and the pulleys are hinged to the substrate at the end of the tube body.
[0040] refer to Figure 3 In a preferred embodiment, the first substrate 411 has a limiting hole for the fixing stop 3 to pass through, and the shape of the limiting hole matches the shape of the fixing stop 3. In this structure, the matching shape of the limiting hole and the fixing stop 3 further stabilizes the trajectory of the inner tube 2 relative to the outer tube 1.
[0041] refer to Figure 2 and Figure 7 A height-adjustable table includes a telescopic sleeve as described above, a tabletop 8, and a support 9, with the telescopic sleeve located between the tabletop 8 and the support 9. Because it includes the telescopic sleeve as described above, it possesses all the beneficial technical effects brought by the telescopic sleeve, which will not be elaborated further here. In a preferred embodiment, the height-adjustable table uses a movable support 9, with casters at the bottom. The main body of the support 9 is constructed of a hollow tube. The fixing stop 3 can be fixed to the end of the outer tube 1 or connected to the support 9. Two possible assembly methods are provided. In embodiment 1, the root of the outer tube 1 is connected to the support 9. The height-adjustable table in embodiment 1 also has a folding function; the head of the inner tube 2 is connected to the tabletop 8 via a folding assembly, the root of the fixing stop 3 extends into the support 9, and the handle assembly 51 is located near the bottom of the tabletop 8. In embodiment 2, the root of the outer tube 1 is connected to the table 8, the head of the inner tube 2 is connected to the support 9, the root of the fixed stop piece 3 extends into the fixed platform, and the handle assembly 51 is close to the support 9, and the switch is controlled by foot pedal.
[0042] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0043] In the description of this specification, the references to terms such as "preferred embodiment," "another embodiment," "other embodiment," or "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0044] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.
Claims
1. A telescopic sleeve, comprising an outer tube (1) and an inner tube (2) sleeved with the outer tube (1), wherein the inner tube (2) is slidable along the outer tube (1), characterized in that: The telescopic sleeve also includes a fixed stop (3) that passes through the core of the outer tube (1) and into the core of the inner tube (2), and a gear adjustment assembly (4) that cooperates with the fixed stop (3). The fixed stop (3) is provided with a plurality of slots (31). The gear adjustment assembly (4) includes a fixed seat (41) connected to the inner tube (2), and a slider (42) that floats on the fixed seat (41). The slider (42) can be engaged with the plurality of slots (31). The gear adjustment assembly (4) also includes a switch assembly (5). The switch assembly (5) is used to adjust the lateral distance between the slider (42) and the fixed stop (3), so that the... The slider (42) leaves the slot (31) so that the inner tube (2) retracts into the outer tube (1), or the slider (42) moves into the slot (31) to restrict the retraction of the inner tube (2); the opening direction of the plurality of slots (31) is inclined toward the direction of the inner tube (2) extending, so that when subjected to a force toward the retraction direction of the inner tube (2), the slider (42) can be held in any slot (31), the stroke range of the slider (42) in the fixed seat (41) is greater than the distance between adjacent slots (31) on the fixed stop (3), and when the fixed seat (41) moves outward with the inner tube (2), it drives the slider (42) to slide into the adjacent slots (31) in sequence.
2. The telescopic sleeve as described in claim 1, characterized in that: The switch assembly (5) includes a handle assembly (51) connected to the inner tube (2) and a rope (52) with one end connected to the slider (42) and the other end connected to the handle assembly (51). The rope (52) is located in the center of the inner tube (2). Pulling the handle assembly (51) can cause the rope (52) to move the slider (42) out of the slot (31) and to the side of the fixed stop (3).
3. A telescopic sleeve according to claim 2, characterized in that: The handle assembly (51) includes a handle (513), a rotating rod (511) that rotates with the handle (513), and a rope connector (512) connected to the rotating rod (511). The two ends of the rotating rod (511) are rotatably connected to the wall of the inner tube (2). The rope connector (512) is sleeved on the rotating rod (511). The rope (52) is connected to the rope connector (512) at a position away from the axis of the rotating rod (511). When the rotating rod (511) pulls the handle (513), the rotating rod (511) rotates. The rotating rod (511) drives the rope connector (512) to rotate. The rope connector (512) drives the rope (52) to move. The rope (52) drives the slider (42) to move out of the slot (31).
4. A telescopic sleeve according to claim 3, characterized in that: The handle (513) includes two support arms (5131) that are respectively connected to both ends of the rotating rod (511), and a handle (5132) that connects the two support arms (5131) into one piece. The two support arms (5131) are respectively tightened to the ends of the rotating rod (511) by bolts.
5. A telescopic sleeve according to claim 4, characterized in that: The rope (52) passes through the fixed seat (41) and is connected to the slider (42). The gear adjustment assembly (4) also includes a spring (43) sleeved on the rope (52) and abutting between the fixed seat (41) and the slider (42).
6. A telescopic sleeve according to claim 5, characterized in that: The fixing seat (41) includes a first base plate (411) covering one end of the inner tube (2) inside the outer tube (1), and a slider seat (412) connected to the first base plate (411) for the slider (42) to be placed in, and the spring (43) abutting against the inner surface of the slider seat (412).
7. A telescopic sleeve according to any one of claims 1-4, characterized in that: The slider (42) includes a movable pin (421) for engaging the slot (31). The fixed base (41) has sliding grooves on both sides for the movable pin (421) to pass through and slide between them. The slider (42) is connected to the fixed base (41) through the movable pin (421).
8. A telescopic sleeve according to any one of claims 1-4, characterized in that: The telescopic sleeve also includes a pulley assembly (6) disposed between the inner tube (2) and the outer tube (1).
9. A telescopic sleeve according to claim 8, characterized in that: The inner tube (2) is covered by a first substrate (411) at one end inside the outer tube (1). The outer tube (1) is covered by a second substrate (7) between the outer tube (1) and the inner tube (2) at one end through which the inner tube (2) passes. The pulley assembly (6) includes a first pulley group (61) connected to the first substrate (411) and a second pulley group (62) connected to the second substrate (7).
10. A height-adjustable desk, characterized in that: Includes a telescopic sleeve as described in any one of claims 1-9, a tabletop (8) and a support (9), wherein the telescopic sleeve is located between the tabletop (8) and the support (9).