A connecting structure and a chair

Abstract

The utility model relates to the field of chair, disclose a connecting structure and chair, can conveniently dismount and assemble chair. The utility model discloses backrest, be equipped with the first buckle of slot, first buckle rotatablely be equipped with backrest, insert piece, can insert the slot and along the slot sliding, insert piece is equipped with the first card slot, elastic piece, one end is connected backrest, the other end connects first buckle, elastic piece is driven by the elastic force and makes first buckle can keep and the carding state of first card slot, drive first buckle can make elastic piece compression, drive backrest relative insert piece and move down or insert piece relative backrest and move up, can make first buckle and first card slot remove the carding state and enter the separation state.

Description

Technical Field

[0001] This utility model relates to the field of chairs, and in particular to a connecting structure and a chair. Background Technology

[0002] In today's daily life, chairs are an indispensable piece of seating. Whether at home, in the office, or in various public spaces, people are almost always with chairs, highlighting their importance. The structural design and assembly process of a chair play a crucial role in the user experience, directly affecting comfort, stability, and long-term convenience when seated.

[0003] However, many current chair designs have a significant drawback. Existing chair seats and backrests are typically fixed together using screws or similar structures, a method that reveals numerous inconveniences in practical use. Firstly, the installation process is relatively cumbersome, requiring specific tools and consuming considerable time and effort, making it unfriendly to the average user. Secondly, disassembly is equally troublesome, especially when the chair needs frequent movement or transport. This inconvenience significantly increases usage costs and causes considerable inconvenience to people's daily lives and work. Utility Model Content

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a connection structure that allows for easy assembly and disassembly of the chair.

[0005] This utility model also proposes a chair having the above-mentioned connection structure.

[0006] On one hand, the connection structure according to the embodiment of this utility model includes:

[0007] The backrest is provided with a slot and a first buckle, the first buckle being rotatably disposed on the backrest;

[0008] A plug-in that can be inserted into the slot and slide along the slot, the plug-in having a first slot;

[0009] An elastic element, one end of which is connected to the backrest, and the other end of which is connected to the first buckle;

[0010] The elastic element is driven by elastic force to enable the first buckle to maintain a snap-fit ​​state with the first slot;

[0011] Driving the first buckle can compress the elastic element, and driving the backrest to move downward relative to the plug or the plug to move upward relative to the backrest can disengage the first buckle and the first slot and enter a separated state.

[0012] According to some embodiments of the present invention, the first buckle sequentially includes a pressing part, a rotating part, and a snap-fit ​​part. The elastic element abuts against the pressing part, the rotating part is rotatably disposed on the backrest, and the snap-fit ​​part is capable of snapping into the first slot.

[0013] According to some embodiments of the present invention, a fixing member is also provided on the backrest, the rotating part includes a rotating shaft, the fixing member and the backrest cooperate to limit the rotating shaft, so that the rotating shaft is rotatably provided on the backrest.

[0014] According to some embodiments of this utility model, when the backrest and the plug are in a separated state, the backrest is driven to move downward relative to the plug or the plug moves upward relative to the backrest. The plug can abut against the lower end of the first buckle, and the first buckle can rotate relative to the backrest and compress the elastic element, so that the first buckle can enter the first slot and enter the snap-fit ​​state.

[0015] According to some embodiments of the present invention, the lower end of the first buckle is provided with a first guide slope, and the plug is provided with a second guide slope above the first slot;

[0016] When the backrest and the plug are in a separated state, the backrest is driven to move downward relative to the plug or the plug moves upward relative to the backrest. The first guide slope can abut against the second guide slope, and the first buckle can rotate relative to the backrest and compress the elastic element, so that the first buckle can enter the first slot and enter the snap-fit ​​state.

[0017] According to some embodiments of the present invention, when the backrest and the plug are in a separated state, pressing the first buckle and compressing the elastic element drives the backrest to move downward relative to the plug or the plug to move upward relative to the backrest, so that the first buckle can enter the first slot and enter a snap-fit ​​state.

[0018] When the backrest and the plug are in the snap-fit ​​state, pressing the first buckle and compressing the elastic element drives the backrest to move upward relative to the plug or the plug to move downward relative to the backrest, which can cause the first buckle to leave the first slot and enter the disengaged state.

[0019] According to some embodiments of the present invention, a height adjustment mechanism is also included, the height adjustment mechanism comprising:

[0020] The second buckle and multiple second slots are provided on the plug-in and the second buckle is rotatably provided on the backrest. The second slots are arranged sequentially along the sliding direction and are all located on the same side of the sliding direction. The multiple second slots open obliquely upward. The second buckle can engage with the second slots to fix the backrest and the plug-in relatively.

[0021] According to some embodiments of the present invention, the height adjustment mechanism further includes:

[0022] A gear adjustment plate is provided on the plug-in, and the gear adjustment plate is provided with a first sliding groove, which surrounds a plurality of second slots;

[0023] The second buckle is rotatably disposed on the backrest, and the second buckle is provided with a movable post, which can slide along the first sliding groove;

[0024] The metal spring sheet, driven by the elastic force of the second buckle, enables the movable column to move in a direction tending towards the second slot, so that the movable column and the second slot can engage.

[0025] According to some embodiments of the present invention, the upper end of the plug is provided with a first guide groove, and the second buckle can pass through the first guide groove.

[0026] On the other hand, the chair according to the present invention includes the connection structure according to the above embodiments of the present invention.

[0027] The embodiments of this utility model have at least the following beneficial effects:

[0028] Quick assembly and disassembly: By directly inserting the plug into the slot of the backrest and sliding it into place, the first buckle automatically engages with the first slot of the plug under the action of the elastic element, thus instantly completing the reliable connection between the seat and the backrest, significantly improving assembly efficiency; conversely, simply drive the first buckle to rotate so that it disengages from the first slot, and the plug can be easily pulled out of the slot, achieving quick separation of the seat and the backrest, which is convenient for transportation, storage or maintenance.

[0029] Stable and reliable connection: The continuous elastic force applied by the elastic element ensures that the first buckle and the first slot are always in a stable locked state, effectively preventing the plug from accidentally loosening or falling out in the slot, and ensuring the structural strength and long-term stability of the connection between the seat and the backrest.

[0030] Simple and efficient structure: The connection structure mainly includes core components such as slots, plugs, rotatable first buckles and elastic elements. It is ingeniously designed, simple in structure, easy to manufacture and assemble, and helps to reduce production costs.

[0031] Easy to operate: The entire installation process (insertion-sliding-automatic snap-fit) and disassembly process (rotating the buckle-pulling out) are all one-way linear or simple rotational operations, requiring no extra labor and can be easily completed by one person;

[0032] Easy to maintain and replace: The quick-release feature makes it extremely convenient to repair, clean or replace parts of the seat or backrest independently, improving the maintainability and lifespan of the product.

[0033] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0034] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0035] Figure 1 This is a schematic diagram of the connection structure in the snap-fit ​​state according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the connection structure in the separated state according to an embodiment of the present invention;

[0037] Figure 3 This is a cross-sectional view and a partially enlarged view of the connection structure in the transition process between the snap-fit ​​and disengaged states according to an embodiment of the present invention.

[0038] Figure 4 This is a cross-sectional view and another enlarged view of the connection structure in the transition process between the snap-fit ​​and disengaged states according to an embodiment of the present invention.

[0039] Figure 5 This is a cross-sectional structural diagram and a partially enlarged diagram of the backrest according to an embodiment of the present utility model;

[0040] Figure 6 This is a schematic diagram of the structure of the plug-in in an embodiment of this utility model;

[0041] Figure 7 This is a schematic diagram of the structure of the second buckle and the metal spring sheet in an embodiment of this utility model;

[0042] Figure 8 This is a schematic diagram of the connection structure of an embodiment of the present utility model, in which the main structure of the backrest is hidden;

[0043] Figure label:

[0044] Backrest 100, slot 110, first buckle 120, pressing part 121, rotating part 122, snap-fit ​​part 123, first guide slope 124, fastener 130, guide plate 140;

[0045] Plug-in 200, first slot 210, second guide slope 230, first guide groove 240, second guide groove 250;

[0046] Elastic element 300;

[0047] Gear adjustment plate 410, first sliding groove 411, second slot 412;

[0048] Second buckle 420, movable column 421;

[0049] Metal rebound sheet 430. Detailed Implementation

[0050] The following will describe several embodiments of the present invention, including embodiments corresponding to the accompanying drawings. It should be understood that the drawings are used to assist in understanding the technical features and technical solutions of the present invention, and should not be construed as limiting the scope of protection of the present invention.

[0051] The following will provide a clear and complete description of the concept, specific structure, and technical effects of this utility model in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution, and effects of this utility model. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0052] It should be noted that, unless otherwise explicitly defined, when a feature is referred to as "fixed," "connected," or "installed" on another feature, it can be directly fixed or connected to the other feature, or it can be indirectly fixed or connected to the other feature. The terms "fixed," "connected," and "installed" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0053] It should be noted that the descriptions of orientations or positional relationships indicated by terms such as up, down, left, right, top, bottom, front, back, inside, and outside used in this utility model are based on the orientations or positional relationships indicated by the accompanying drawings or embodiments. They are only for the purpose of facilitating the description of this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0054] It should be noted that the term "and / or" used in this utility model includes any combination of one or more of the related listed items, "several" means one or more, "multiple" means two or more, "greater than", "less than", "exceeding" are understood to exclude the number itself, and "above", "below", "within" are understood to include the number itself.

[0055] It should be noted that the use of "first" and "second" in this utility model is only for the purpose of distinguishing technical features, and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated.

[0056] It should be noted that, unless otherwise expressly 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 not for limiting the scope of the invention.

[0057] Reference Figures 1-8 The basic embodiment of the first aspect of this utility model provides a connection structure, including:

[0058] The backrest 100 is provided with a slot 110 and a first buckle 120, the first buckle 120 being rotatably provided on the backrest 100;

[0059] The plug-in 200 is capable of being inserted into the slot 110 and sliding along the slot 110, and the plug-in 200 is provided with a first slot 210;

[0060] Elastic element 300, one end of which is connected to backrest 100, and the other end is connected to first buckle 120;

[0061] The elastic element 300 is driven by elastic force to enable the first buckle 120 to maintain the engagement state with the first slot 210;

[0062] Driving the first latch 120 can compress the elastic element 300, and driving the backrest 100 to move downward relative to the plug 200 or the plug 200 to move upward relative to the backrest 100 can disengage the first latch 120 and the first slot 210 and enter the separation state.

[0063] According to the embodiments of this utility model, the following effects can be achieved through this configuration: Quick assembly and disassembly: By directly inserting the plug 200 into the slot 110 of the backrest 100 and sliding it into place, the first buckle 120 automatically engages with the first slot 210 of the plug 200 under the action of the elastic element 300, instantly completing a reliable connection between the seat and the backrest 100, significantly improving assembly efficiency; Conversely, simply driving the first buckle 120 to rotate and disengage it from the first slot 210 allows the plug 200 to be easily pulled out of the slot 110, achieving rapid separation of the seat and backrest 100, facilitating transportation, storage, or maintenance; Stable and reliable connection: The continuous elastic force applied by the elastic element 300 ensures that the first buckle 120 and the first slot 210 are always in a stable locked state, effectively preventing the plug 200 from accidentally loosening or coming out of the slot 110, ensuring the structural strength and long-term stability of the connection between the seat and the backrest 100. Simple and efficient structure: The connection structure mainly includes core components such as slot 110, plug 200, rotatable first buckle 120, and elastic element 300. The design is ingenious, the structure is simple, easy to manufacture and assemble, and helps to reduce production costs. Convenient operation: The entire installation process (insertion-sliding-automatic snap-fit) and disassembly process (rotating buckle-pulling out) are unidirectional linear or simple rotational operations, requiring no extra labor and can be easily completed by a single person. Easy maintenance and replacement: The quick-release feature makes it extremely convenient to independently repair, clean, or replace parts of the seat or backrest 100, improving the maintainability and service life of the product.

[0064] It should be noted that the sliding direction refers to the direction of relative movement between the backrest 100 and the plug 200. Here, the plug 200 slides along the slot 110, so the sliding direction is also the extension direction of the slot 110. The sliding direction mentioned later is the same.

[0065] In some embodiments, the elastic element 300 may be replaced by a spring, torsion spring, sheet metal or other elastic material.

[0066] In some embodiments, in a first embodiment of the first latch 120, the first latch 120 sequentially includes a pressing part 121, a rotating part 122, and a locking part 123. An elastic member 300 abuts against the pressing part 121, the rotating part 122 is rotatably disposed on the backrest 100, and the locking part 123 can lock into the first slot 210. By pressing the pressing part 121 to rotate it, the locking part 123 also rotates, thereby causing the locking part 123 to separate from the first slot 210. This method makes it relatively convenient to release the latch.

[0067] In some embodiments, in a second embodiment of the first buckle 120, one end of the first buckle 120 is rotatably disposed on the backrest 100, and one side of the other end is connected to the elastic member 300, and the other side is engaged with the first slot 210. It can be understood that this is equivalent to the engaging part 123 and the elastic member 300 being disposed on the same side of the first buckle 120 in the previous direction.

[0068] In some embodiments, in a third embodiment of the first buckle 120, the first buckle 120 may be an iron pin, a plastic part, or another metal part.

[0069] In some embodiments, a fixing member 130 is also provided on the backrest 100, and the rotating part 122 includes a rotating shaft. The fixing member 130 and the backrest 100 cooperate to limit the rotating shaft, so that the rotating shaft is rotatably provided on the backrest 100. The fixing member 130 can be a screw or a bolt. The fixing member 130 is fixedly provided on the backrest 100, and the rotating shaft is provided between the nut of the fixing member 130 and the backrest 100, so that the rotating shaft is restricted on the backrest 100 but its rotation is not restricted.

[0070] In some embodiments, when the backrest 100 and the insert 200 are in a separated state, driving the backrest 100 to move downward relative to the insert 200 or the insert 200 to move upward relative to the backrest 100 allows the insert 200 to abut against the lower end of the first latch 120. The first latch 120 can rotate relative to the backrest 100 and compress the elastic element 300, allowing the first latch 120 to enter the first slot 210 and enter a snap-fit ​​state. The ends of the insert 200 and the first latch 120 can be arc-shaped or beveled, and when they abut against each other, they generate an interaction force, enabling the rotation of the first latch 120.

[0071] It should be noted that the insertion plug 200 can move upward relative to the backrest 100 due to external force, or the backrest 100 can move downward relative to the insertion plug 200; both are equivalent.

[0072] In some embodiments, the lower end of the first buckle 120 is provided with a first guide slope 124, and the plug-in 200 is provided with a second guide slope 230 above the first slot 210.

[0073] When the backrest 100 and the plug-in 200 are in a separated state, driving the backrest 100 to move downward relative to the plug-in 200 or the plug-in 200 to move upward relative to the backrest 100 causes the first guide slope 124 to abut against the second guide slope 230. The first latch 120 can rotate relative to the backrest 100 and compress the elastic element 300, allowing the first latch 120 to enter the first slot 210 and engage. When the first guide slope 124 abuts against the end of the plug-in 200, the first latch 120 can rotate under the guidance of the guide slope, causing the first latch 120 to be in a separated state. Continuing to move the plug-in 200 causes the first latch 120 to rotate under the action of the elastic element 300, allowing the first latch 120 to engage with the first slot 210.

[0074] In some embodiments, the plug-in 200 has a second guide slope 230 above the first slot 210. When the backrest 100 and the plug-in 200 are separated, and the backrest 100 moves downward relative to the plug-in 200 under the action of an external force, the second guide slope 230 can abut against the end of the first buckle 120, allowing the first buckle 120 to enter the first slot 210 and enter a snap-fit ​​state. The second guide slope 230 works similarly to the first guide slope 124 described above.

[0075] In some embodiments, when the backrest 100 and the plug-in 200 are in a separated state, pressing the first buckle 120 and compressing the elastic element 300 drives the backrest 100 to move downward relative to the plug-in 200 or the plug-in 200 to move upward relative to the backrest 100, which enables the first buckle 120 to enter the first slot 210 and enter a snap-fit ​​state.

[0076] When the backrest 100 and the plug 200 are in the snap-fit ​​state, pressing the first buckle 120 and compressing the elastic element 300 drives the backrest 100 to move upward relative to the plug 200 or the plug 200 to move downward relative to the backrest 100, which can cause the first buckle 120 to leave the first slot 210 and enter the disengaged state.

[0077] In this configuration, pressing the first buckle allows the first buckle and the first slot to engage or disengage. When disengaged, the backrest and the insert can move relative to each other, allowing them to be installed or removed.

[0078] In some embodiments, a height adjustment mechanism is further included. This mechanism includes a second latch 420 and a plurality of second slots 412. The second slots 412 are disposed on the insert 200, and the second latch 420 is rotatably disposed on the backrest 100. The second slots 412 are sequentially arranged along the sliding direction and are all located on the same side of the sliding direction. The plurality of second slots 412 open obliquely upwards. The second latch 420 can engage with the second slots 412, thereby fixing the backrest 100 and the insert 200 relatively. The backrest 100 and the seat can slide relative to each other. The second latch 422 can engage with different second slots 412, fixing the backrest 100 at different heights to accommodate different user habits.

[0079] In some embodiments, the height adjustment mechanism further includes:

[0080] The gear adjustment plate 410 is provided in the plug-in 200. The gear adjustment plate 410 is provided with a first sliding groove 411, which surrounds a plurality of second slots 412.

[0081] The second buckle 420 is rotatably mounted on the backrest 100. The second buckle 420 is provided with a movable post 421, which can slide along the first sliding groove 411.

[0082] The metal spring sheet 430 and the second buckle 420 are driven by the elastic force of the metal spring sheet 430 to enable the movable column 421 to move in a direction tending towards the second slot 412, so that the movable column 421 and the second slot 412 can be engaged.

[0083] In this configuration, the relative sliding of the gear adjustment plate 410 and the second buckle 420 allows the second buckle 420 to engage with different second slots 412, thus positioning the backrest 100 at different heights. Guided by the first sliding groove 411, the movable column 421 on the second buckle 420 rotates accordingly, allowing it to slide along the first sliding groove 411. During the movement of the movable column 421, the elasticity of the metal spring sheet 430 causes it to rotate towards the second slot 412, enabling the second buckle 420 to engage with the second slot 412. Continuing to apply external force can disengage the movable column 421 from the second slot 412, allowing the second buckle 420 to engage with the second slot 412 in sequence, thus adjusting the height according to user needs.

[0084] In some embodiments, the upper end of the plug 200 is provided with a first guide groove 240, and the second buckle 420 can pass through the first guide groove 240 and enter the first sliding groove 411. The width of the second buckle 420 is smaller and can pass through the first guide groove 240, while the width of the first buckle 120 is larger and cannot pass directly through the first guide groove 240, but enters the separated state through the guide slope of the surface.

[0085] In some embodiments, the length of the first slot 210 in the sliding direction is greater than the total length of the plurality of second slots 412. The engaging portion 123 can slide within the first slot 210, and the sliding distance is greater than the distance between the plurality of second slots 412, which allows the backrest and seat to slide relative to each other, which is beneficial for adjusting the height of the backrest 100.

[0086] In some embodiments, the length of the first slot 210 in the sliding direction is greater than the length of the engaging portion 123 on the first buckle 120, allowing the engaging portion 123 to slide in the first slot 210. The ability of the engaging portion 123 to slide within the first slot 210 enables the backrest and seat to slide relative to each other, which is beneficial for adjusting the height of the backrest 100.

[0087] In some embodiments, the insert 200 is provided with a second guide groove 250, and the backrest 100 is provided with a guide plate 140. The guide plate 140 can cooperate with the second guide groove 250, so that the guide plate 140 slides along the second guide groove 250. The cooperation between the guide plate 140 and the second guide groove 250 plays a guiding role, which is beneficial to guiding the insert to slide.

[0088] It should be noted that in this specification, terms such as "one embodiment", "some embodiments", "basic embodiment", and "extended embodiment" may be used to describe several embodiments of the present invention, and the specific features, structures, materials or characteristics of the several embodiments may be combined in accordance with the principles and spirit of the present invention.

[0089] Although some embodiments of the present utility model have been shown and described in this specification, the present utility model should not be limited to the above embodiments. As long as they achieve the technical effects of the present utility model by the same or equivalent means, any changes, modifications, equivalent substitutions and equivalent variations of these embodiments within the spirit and principles disclosed in the present utility model, without departing from the principles and purpose of the present utility model, should be included within the scope of protection disclosed in the present utility model and should be considered to fall within the protection scope of the present utility model.

Claims

1. A connection structure, characterized in that, include: The backrest (100) is provided with a slot (110) and a first buckle (120), the first buckle (120) being rotatably disposed on the backrest (100); A plug-in (200) is capable of being inserted into the slot (110) and sliding along the slot (110), the plug-in (200) being provided with a first slot (210); An elastic element (300) has one end connected to the backrest (100) and the other end connected to the first buckle (120); The elastic element (300) is driven by elastic force to enable the first buckle (120) to maintain a snap-fit ​​state with the first slot (210); Driving the first buckle (120) can compress the elastic element (300), drive the backrest (100) to move downward relative to the plug (200) or drive the plug (200) to move upward relative to the backrest (100), and can disengage the first buckle (120) and the first slot (210) and enter the separation state.

2. The connection structure according to claim 1, characterized in that: The first buckle (120) includes a pressing part (121), a rotating part (122) and a locking part (123) in sequence. The elastic member (300) abuts against the pressing part (121), the rotating part (122) is rotatably disposed on the backrest (100), and the locking part (123) can lock into the first slot (210).

3. The connection structure according to claim 2, characterized in that: It also includes a fixing member (130) disposed on the backrest (100), the rotating part (122) includes a rotating shaft, the fixing member (130) and the backrest (100) cooperate to limit the rotating shaft, so that the rotating shaft is rotatably disposed on the backrest (100).

4. The connection structure according to claim 1, characterized in that: When the backrest (100) and the plug (200) are in a separated state, the backrest (100) is driven to move downward relative to the plug (200) or the plug (200) is driven to move upward relative to the backrest (100). The plug (200) can abut against the lower end of the first buckle (120). The first buckle (120) can rotate relative to the backrest (100) and compress the elastic element (300), so that the first buckle (120) can enter the first slot (210) and enter the snap-fit ​​state.

5. The connection structure according to claim 4, characterized in that: The lower end of the first buckle (120) is provided with a first guide slope (124), and the plug (200) is provided with a second guide slope (230) above the first slot (210); When the backrest (100) and the plug (200) are in a separated state, the backrest (100) is driven to move downward relative to the plug (200) or the plug (200) is driven to move upward relative to the backrest (100). The first guide slope (124) can abut against the second guide slope (230), and the first buckle (120) can rotate relative to the backrest (100) and compress the elastic element (300), so that the first buckle (120) can enter the first slot (210) and enter the snap-fit ​​state.

6. The connection structure according to claim 1, characterized in that: When the backrest (100) and the plug (200) are in a separated state, pressing the first buckle (120) and compressing the elastic element (300) drives the backrest (100) to move downward relative to the plug (200) or the plug (200) to move upward relative to the backrest (100), so that the first buckle (120) can enter the first slot (210) and enter the snap-fit ​​state; When the backrest (100) and the plug (200) are in the snap-fit ​​state, pressing the first buckle (120) and compressing the elastic element (300) drives the backrest (100) to move upward relative to the plug (200) or the plug (200) to move downward relative to the backrest (100), which can cause the first buckle (120) to leave the first slot (210) and enter the disengaged state.

7. The connection structure according to claim 1, characterized in that: It also includes a height adjustment mechanism, which comprises: The second buckle (420) and a plurality of second slots (412) are provided on the plug (200). The second buckle (420) is rotatably provided on the backrest (100). The second slots (412) are arranged sequentially along the sliding direction and are all located on the same side of the sliding direction. The plurality of second slots (412) open obliquely upward. The second buckle (420) can engage with the second slots (412) to fix the backrest (100) and the plug (200) relatively.

8. The connection structure according to claim 7, characterized in that: The height adjustment mechanism also includes: A gear adjustment plate (410) is provided on the plug-in (200). The gear adjustment plate (410) is provided with a first sliding groove (411). The first sliding groove (411) is arranged around a plurality of second slots (412). The second buckle (420) is rotatably disposed on the backrest (100). The second buckle (420) is provided with a movable post (421), which can slide along the first sliding groove (411). The metal spring sheet (430) and the second buckle (420) are driven by the elastic force of the metal spring sheet (430) to enable the movable post (421) to move in a direction tending towards the second slot (412), so that the movable post (421) and the second slot (412) can be engaged.

9. The connection structure according to claim 7, characterized in that: The upper end of the plug (200) is provided with a first guide groove (240), and the second buckle (420) can pass through the first guide groove (240).

10. A chair, characterized in that: Includes the connection structure as described in any one of claims 1 to 9.

Images