Multi-form combined detachable sandbox

By designing a detachable sandbox with multiple forms and using the combination of connecting plates and connectors, the sandbox's sand leakage and shape fixation problems are solved, achieving the effect of simple structure, diverse changes and strong adaptability of the sandbox.

CN223220962UActive Publication Date: 2025-08-15SHANTOU HONGKAI TECHNOLOGY IND CO LTD
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Patent Information

Application Number
CN202422409376.X
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-09-30
Publication Date
2025-08-15
Estimated Expiration
2034-09-30

AI Technical Summary

Technical Problem

The existing sandboxes are prone to leakage of sand in the connection part during use, the structure is not compact, and cannot be disassembled and fixed in shape, so they cannot meet the needs of different sites.

Method used

A multi-form combination detachable sandbox is designed. Through the combination of the connecting plate and the connector, a variety of combinations of the upper case and the lower case are formed. The fixed splicing of the positioning column, through holes and nuts, and the locking structure of the support seats is realized to achieve detachable and diversified combinations.

Benefits of technology

The sandbox has a simple structure, diverse variations, flexible combinations, easy use, and adapts to the needs of different sites, solving the problems of sand leakage and fixed shape of existing sandboxes.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model provides a multi-form combined detachable sandbox which comprises an upper shell and a lower shell, the detachable upper shell is arranged above the lower shell, a cavity is formed in the lower shell, the lower shell is formed by splicing a plurality of connecting plate assemblies to form multiple combinations, and the lower shell is provided with a plurality of connecting plate assemblies. The beneficial effects of the utility model are that the connecting pieces are connected with the first connecting plate, the second connecting plate, the third connecting plate, the fourth connecting plate, the fifth connecting plate, the sixth connecting plate, the first upper shell connecting plate, the second upper shell connecting plate, the third upper shell connecting plate and the fourth upper shell connecting plate to form various combinations of the upper shell and the lower shell, so that the structure is simple; and the combination is flexible, the use is moderate and simple, and the popularization and application are better.
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Description

Technical Field

[0001] The utility model belongs to the technical field of children's toys and relates to a detachable sandbox with multiple forms. Background Art

[0002] Many residential communities and kindergartens now have sandboxes filled with sea sand, and some even have toys inside, for children to play with, exercising their hands-on skills, imagination, and developing their intelligence. However, existing sandboxes are usually made of hard plastic and spliced together. During use, sand easily leaks from the connected parts, resulting in a loose structure. Moreover, the existing sandboxes have a fixed shape after assembly and cannot be disassembled. They cannot be deformed to adapt to various venues, making them inconvenient to use. Utility Model Content

[0003] The purpose of the present invention is to solve the above technical problems and to provide a new type of detachable sandbox with multiple forms.

[0004] To achieve the above-mentioned purpose, the utility model provides a detachable sandbox with multiple forms of combination, including an upper shell and a lower shell. A detachable upper shell is provided above the lower shell, a cavity is provided inside the lower shell, and the lower shell is spliced by several connecting plate assemblies to form multiple combinations.

[0005] As a further feature, the connecting plate assembly includes a first connecting plate, a second connecting plate, a third connecting plate, a fourth connecting plate, a fifth connecting plate, a sixth connecting plate, and a connecting piece;

[0006] A plurality of positioning posts are provided on one edge of the first connecting plate, a plurality of through holes are provided on the other edge of the first connecting plate, a through hole is provided on one edge of the second connecting plate that matches the through hole on one edge of the first connecting plate, the through hole on one edge of the second connecting plate is embedded in the positioning posts on one edge of the first connecting plate, and the second connecting plate is fixedly spliced to the first connecting plate by nuts;

[0007] A plurality of positioning posts are provided on the other side edge of the second connecting plate, and a through hole is provided on one side edge of the third connecting plate that matches the through hole on the other side edge of the second connecting plate. The through hole on one side edge of the third connecting plate is embedded in the positioning post on the other side edge of the second connecting plate, and the third connecting plate is fixedly spliced to the second connecting plate by nuts;

[0008] A plurality of positioning posts are provided on the other side edge of the third connecting plate, and a through hole is provided on one side edge of the fourth connecting plate that matches the through hole on the other side edge of the third connecting plate. The through hole on one side edge of the fourth connecting plate is embedded in the positioning post on the other side edge of the third connecting plate, and the fourth connecting plate is fixedly spliced to the third connecting plate by nuts;

[0009] The first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate are spliced together by connecting parts to form an integral lower shell. A fifth connecting plate is provided between the first connecting plate and the front end of the fourth connecting plate, and a sixth connecting plate is provided between the second connecting plate and the rear end of the third connecting plate.

[0010] Furthermore, the rear end of the fifth connecting plate is provided with a clamping strip, and the front ends of the first connecting plate and the fourth connecting plate are provided with protrusions. The clamping strip at the rear end of the fifth connecting plate is attached to the protrusions at the front ends of the first connecting plate and the fourth connecting plate, and is seamlessly spliced and buckled together.

[0011] Furthermore, a clamping strip is provided at the front end of the sixth connecting plate, and protrusions are provided at the rear ends of the second connecting plate and the third connecting plate. The clamping strip at the front end of the sixth connecting plate fastens the second connecting plate and the protrusions at the front end of the third connecting plate and snaps them together seamlessly.

[0012] Furthermore, the outer side walls of the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate are provided with supporting feet.

[0013] Furthermore, the support foot includes a lower support foot, an upper support foot, and a locking column. The upper support foot is provided above the lower support foot. The upper support foot is respectively located on the outer walls of the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate. The upper support foot is locked on the lower support foot by the locking column.

[0014] Furthermore, the upper support foot is integrally formed with the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate respectively.

[0015] Furthermore, the upper shell is formed by splicing a plurality of upper shell connecting plate assemblies to form a variety of combinations.

[0016] As a further feature, the upper shell connecting plate assembly includes a first upper shell connecting plate, a second upper shell connecting plate, a third upper shell connecting plate, a fourth upper shell connecting plate, and an upper shell connecting plate connector;

[0017] A plurality of upper shell latches are provided on the inner edge of one side of the first upper shell connecting plate, and an upper shell through-hole matching the upper shell latch on the inner edge of one side of the first upper shell connecting plate is provided on the inner edge of one side of the second upper shell connecting plate. The upper shell latch on the inner edge of one side of the first upper shell connecting plate is embedded in the upper shell through-hole on the inner edge of one side of the second upper shell connecting plate, and the first upper shell connecting plate is fixedly spliced to the second upper shell connecting plate; a plurality of upper shell through-holes are provided on the inner edge of the other side of the first upper shell connecting plate;

[0018] A plurality of upper shell latches are provided on the inner edge of the other side of the second upper shell connecting plate, and an upper shell through-hole matching the upper shell latches on the inner edge of one side of the second upper shell connecting plate is provided on the inner edge of one side of the third upper shell connecting plate. The upper shell latches on the inner edge of the other side of the second upper shell connecting plate are embedded in the upper shell through-holes on the inner edge of one side of the third upper shell connecting plate, and the second upper shell connecting plate is fixedly spliced to the third upper shell connecting plate;

[0019] A plurality of upper shell latches are provided on the inner edge of the other side of the third upper shell connecting plate, and an upper shell through-hole matching the upper shell latches on the inner edge of one side of the third upper shell connecting plate is provided on the inner edge of one side of the fourth upper shell connecting plate. The upper shell latches on the inner edge of the other side of the third upper shell connecting plate are embedded in the upper shell through-holes on the inner edge of one side of the fourth upper shell connecting plate, and the third upper shell connecting plate is fixedly spliced to the fourth upper shell connecting plate;

[0020] A plurality of upper shell latches are provided on the inner edge of the other side of the fourth upper shell connecting plate. The upper shell latches on the inner edge of the other side of the fourth upper shell connecting plate are embedded in the upper shell through holes on the inner edge of the other side of the first upper shell connecting plate, and the fourth upper shell connecting plate is fixedly spliced to the first upper shell connecting plate;

[0021] A plurality of pin holes are provided inside the upper shell connecting plate connecting piece. The upper shell pins of the first upper shell connecting plate, the second upper shell connecting plate, the third upper shell connecting plate and the fourth upper shell connecting plate are inserted into the pin holes inside the upper shell connecting plate connecting piece and spliced together to form an integral upper shell.

[0022] The beneficial effects of the present invention compared with the prior art are as follows: through the connection of the connecting parts with the first connecting plate, the second connecting plate, the third connecting plate, the fourth connecting plate, the fifth connecting plate, the sixth connecting plate and the first upper shell connecting plate, the second upper shell connecting plate, the third upper shell connecting plate, and the fourth upper shell connecting plate, a variety of combinations of upper shells and lower shells are formed, the structure is simple, the changes are diverse, the combination is flexible, the use is moderately simple, and it has good promotion and application.

[0023] In order to more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the detachable sandbox structure with multiple forms of combination according to the present invention;

[0025] Figure 2 This is a schematic diagram of the detachable sandbox explosion structure with multiple forms of combination according to the present invention;

[0026] Figure 3 This is a schematic diagram of the upper shell structure of the utility model;

[0027] Figure 4 This is a schematic diagram of the explosion structure of the upper shell of the utility model;

[0028] Figure 5 This is a schematic diagram of the lower shell structure of the utility model;

[0029] Figure 6 This is a schematic diagram of the explosion structure of the lower shell of the utility model;

[0030] Figure markings: 1. upper shell; 101. first upper shell connecting plate; 102. second upper shell connecting plate; 103. third upper shell connecting plate; 104. fourth upper shell connecting plate; 105. upper shell connecting plate connecting piece; 1050. latch hole; 106. upper shell latch; 107. upper shell through hole; 2. lower shell; 21. cavity; 22. connecting plate assembly; 220. first connecting plate; 221. second connecting plate; 222. third connecting plate; 223. fourth connecting plate; 224. fifth connecting plate; 225. sixth connecting plate; 226. connecting piece; 227. positioning column; 228. through hole; 229. clamping strip; 230. protrusion; 231. support foot; 2310. upper support foot; 2311. lower support foot; 2312. locking column. DETAILED DESCRIPTION

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0032] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] Refer to Figures 1-6 As shown, an embodiment of the utility model provides a detachable sandbox with multiple forms of combinations, including an upper shell 1 and a lower shell 2. A detachable upper shell 2 is provided above the lower shell 2, and a cavity 21 is provided inside the lower shell 2. The lower shell 2 is spliced by several connecting plate assemblies 22 to form multiple combinations.

[0034] Preferably, the connecting plate assembly 22 includes a first connecting plate 220, a second connecting plate 221, a third connecting plate 222, a fourth connecting plate 223, a fifth connecting plate 224, a sixth connecting plate 225, and a connecting piece 226;

[0035] A plurality of positioning posts 227 are provided on one edge of the first connecting plate 220, and a plurality of through holes 228 are provided on the other edge of the first connecting plate 220. A through hole 228 matching the through hole 228 on one edge of the first connecting plate 220 is provided on one edge of the second connecting plate 221. The through holes 228 on one edge of the second connecting plate 221 are embedded in the positioning posts 227 on one edge of the first connecting plate 220, and the second connecting plate 221 is fixed to the first connecting plate 220 by nuts.

[0036] A plurality of positioning posts 227 are provided on the other side edge of the second connecting plate 221. A through hole 228 matching the through hole 228 on the other side edge of the second connecting plate 221 is provided on one side edge of the third connecting plate 222. The through hole 228 on one side edge of the third connecting plate 222 is embedded in the positioning post 227 on the other side edge of the second connecting plate 221, and the third connecting plate 222 is fixed to the second connecting plate 221 by nuts.

[0037] A plurality of positioning posts 227 are provided on the other side edge of the third connecting plate 222. A through hole 228 matching the through hole 228 on the other side edge of the third connecting plate 222 is provided on one side edge of the fourth connecting plate 223. The through hole 228 on one side edge of the fourth connecting plate 223 is embedded in the positioning post 227 on the other side edge of the third connecting plate 222, and the fourth connecting plate 223 is fixed to the third connecting plate 222 by nuts.

[0038] The first connecting plate 220, the second connecting plate 221, the third connecting plate 222 and the fourth connecting plate 223 are spliced together by a connecting piece 226 to form an integral lower shell 2. A fifth connecting plate 224 is provided between the front ends of the first connecting plate 220 and the fourth connecting plate 223, and a sixth connecting plate 225 is provided between the rear ends of the second connecting plate 221 and the third connecting plate 222.

[0039] Preferably, a clamping strip 229 is provided at the rear end of the fifth connecting plate 224, and a protrusion 230 is provided at the front end of the first connecting plate 220 and the fourth connecting plate 223. The clamping strip 229 at the rear end of the fifth connecting plate 224 fastens the first connecting plate 220 and the protrusion 230 at the front end of the fourth connecting plate 223, and seamlessly splices and fastens them together.

[0040] Preferably, a clamping strip 229 is provided at the front end of the sixth connecting plate 225, and a protrusion 230 is provided at the rear end of the second connecting plate 221 and the third connecting plate 222. The clamping strip 229 at the front end of the sixth connecting plate 225 fastens the second connecting plate 221 and the protrusion 230 at the front end of the third connecting plate 222, and seamlessly splices and fastens them together.

[0041] Preferably, support feet 231 are provided on the outer side walls of the first connecting plate 220 , the second connecting plate 221 , the third connecting plate 222 and the fourth connecting plate 223 .

[0042] Preferably, the support foot 231 includes a lower support foot 2310, an upper support foot 2311, and a locking column 2312. An upper support foot 2311 is provided above the lower support foot 2310. The upper support foot 2311 is respectively located on the outer walls of the first connecting plate 220, the second connecting plate 221, the third connecting plate 222 and the fourth connecting plate 223. The upper support foot 2311 is locked on the lower support foot 2310 by the locking column 2312.

[0043] Preferably, the upper support 2311 is integrally formed with the first connecting plate 220 , the second connecting plate 221 , the third connecting plate 222 and the fourth connecting plate 223 .

[0044] Preferably, the upper shell 11 is formed by splicing a plurality of upper shell connecting plate assemblies to form various combinations.

[0045] Preferably, the upper shell connecting plate assembly includes a first upper shell connecting plate 101, a second upper shell connecting plate 102, a third upper shell connecting plate 103, a fourth upper shell connecting plate 104, and an upper shell connecting plate connector 105;

[0046] The first upper shell connecting plate 101 is provided with a plurality of upper shell latches 106 on the inner edge of one side, and the second upper shell connecting plate 102 is provided with an upper shell through-hole 107 on the inner edge of one side of the first upper shell connecting plate 101, which matches the upper shell latches on the inner edge of one side of the first upper shell connecting plate 101. The upper shell latches 106 on the inner edge of one side of the first upper shell connecting plate 101 are embedded in the upper shell through-hole 107 on the inner edge of one side of the second upper shell connecting plate 102, and the first upper shell connecting plate 101 is fixedly spliced to the second upper shell connecting plate 102; the first upper shell connecting plate 101 is provided with a plurality of upper shell through-holes 107 on the inner edge of the other side;

[0047] A plurality of upper shell latches 106 are provided on the inner edge of the other side of the second upper shell connecting plate 102. An upper shell through-hole 107 matching the upper shell latches 106 on the inner edge of one side of the second upper shell connecting plate 102 is provided on the inner edge of one side of the third upper shell connecting plate 103. The upper shell latches 106 on the inner edge of the other side of the second upper shell connecting plate 102 are embedded in the upper shell through-hole 107 on the inner edge of one side of the third upper shell connecting plate 103, and the second upper shell connecting plate 102 is fixedly spliced to the third upper shell connecting plate 103.

[0048] A plurality of upper shell latches 106 are provided on the inner edge of the other side of the third upper shell connecting plate 103. An upper shell through-hole 107 matching the upper shell latches 106 on the inner edge of one side of the third upper shell connecting plate 103 is provided on the inner edge of one side of the fourth upper shell connecting plate 104. The upper shell latches 106 on the inner edge of the other side of the third upper shell connecting plate 103 are embedded in the upper shell through-hole 107 on the inner edge of one side of the fourth upper shell connecting plate 104, and the third upper shell connecting plate 103 is fixedly spliced to the fourth upper shell connecting plate 104.

[0049] A plurality of upper shell latches 106 are provided on the inner edge of the other side of the fourth upper shell connecting plate 104. The upper shell latches 106 on the inner edge of the other side of the fourth upper shell connecting plate 104 are embedded in the upper shell through holes 107 on the inner edge of the other side of the first upper shell connecting plate 101, and the fourth upper shell connecting plate 104 is fixedly spliced to the first upper shell connecting plate 101;

[0050] A plurality of latch holes 1050 are provided inside the upper shell connecting plate connecting piece 105. The upper shell latches 106 of the first upper shell connecting plate 101, the second upper shell connecting plate 102, the third upper shell connecting plate 103 and the fourth upper shell connecting plate 104 are inserted into the latch holes 1050 inside the upper shell connecting plate connecting piece 105 and spliced together to form an integral upper shell 1.

[0051] The above description of the technical principles of the present invention in conjunction with specific embodiments is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention fall within the scope of protection of the present invention. Those skilled in the art can easily conceive of other specific embodiments of the present invention without inventive effort, and all of them fall within the scope of protection of the present invention.

Claims

1. A detachable sandbox with multiple forms, characterized by: It includes an upper shell and a lower shell. A detachable upper shell is provided above the lower shell. A cavity is provided inside the lower shell. The lower shell is formed by splicing a number of connecting plate assemblies to form various combinations.

2. The multi-modal detachable sandbox according to claim 1, characterized in that: The connecting plate assembly includes a first connecting plate, a second connecting plate, a third connecting plate, a fourth connecting plate, a fifth connecting plate, a sixth connecting plate, and a connecting piece; A plurality of positioning posts are provided on one edge of the first connecting plate, a plurality of through holes are provided on the other edge of the first connecting plate, a through hole is provided on one edge of the second connecting plate that matches the through hole on one edge of the first connecting plate, the through hole on one edge of the second connecting plate is embedded in the positioning posts on one edge of the first connecting plate, and the second connecting plate is fixedly spliced to the first connecting plate by nuts; A plurality of positioning posts are provided on the other side edge of the second connecting plate, and a through hole is provided on one side edge of the third connecting plate that matches the through hole on the other side edge of the second connecting plate. The through hole on one side edge of the third connecting plate is embedded in the positioning post on the other side edge of the second connecting plate, and the third connecting plate is fixedly spliced to the second connecting plate by nuts; A plurality of positioning posts are provided on the other side edge of the third connecting plate, and a through hole is provided on one side edge of the fourth connecting plate that matches the through hole on the other side edge of the third connecting plate. The through hole on one side edge of the fourth connecting plate is embedded in the positioning post on the other side edge of the third connecting plate, and the fourth connecting plate is fixedly spliced to the third connecting plate by nuts; The center of the circle formed by splicing the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate is spliced together through a connecting piece to form an integral lower shell. A fifth connecting plate is provided between the first connecting plate and the front end of the fourth connecting plate, and a sixth connecting plate is provided between the second connecting plate and the rear end of the third connecting plate.

3. The multi-modal detachable sandbox according to claim 2, characterized in that: The rear end of the fifth connecting plate is provided with a clamping strip, and the front ends of the first connecting plate and the fourth connecting plate are provided with protrusions. The clamping strip at the rear end of the fifth connecting plate is attached to the protrusions at the front ends of the first connecting plate and the fourth connecting plate, and is seamlessly spliced and buckled together.

4. The multi-modal detachable sandbox according to claim 2, characterized in that: The front end of the sixth connecting plate is provided with a clamping strip, and the rear ends of the second connecting plate and the third connecting plate are provided with protrusions. The clamping strip at the front end of the sixth connecting plate is attached to the protrusions at the front ends of the second connecting plate and the third connecting plate, and is seamlessly spliced and buckled together.

5. The multi-modal detachable sandbox according to claim 2, characterized in that: The outer side walls of the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate are provided with supporting feet.

6. The multi-modal detachable sandbox according to claim 5, characterized in that: The support foot includes a lower support foot, an upper support foot, and a locking column. The upper support foot is provided above the lower support foot. The upper support foot is respectively located on the outer side walls of the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate. The upper support foot is locked on the lower support foot by the locking column.

7. The multi-modal detachable sandbox according to claim 6, characterized in that: The upper support base is integrally formed with the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate respectively.

8. The multi-modal detachable sandbox according to claim 1, characterized in that: The upper shell is formed by splicing a plurality of upper shell connecting plate assemblies to form various combinations.

9. The multi-modal detachable sandbox according to claim 8, characterized in that: The upper shell connecting plate assembly includes a first upper shell connecting plate, a second upper shell connecting plate, a third upper shell connecting plate, a fourth upper shell connecting plate, and an upper shell connecting plate connector; A plurality of upper shell latches are provided on the inner edge of one side of the first upper shell connecting plate, and a through hole is provided on the inner edge of one side of the second upper shell connecting plate to match the upper shell latches on the inner edge of one side of the first upper shell connecting plate. The upper shell latches on the inner edge of one side of the first upper shell connecting plate are embedded in the upper shell through holes on the inner edge of one side of the second upper shell connecting plate, and the first upper shell connecting plate is fixedly spliced to the second upper shell connecting plate; a plurality of upper shell through holes are provided on the inner edge of the other side of the first upper shell connecting plate; A plurality of upper shell latches are provided on the inner edge of the other side of the second upper shell connecting plate, and an upper shell through-hole matching the upper shell latches on the inner edge of one side of the second upper shell connecting plate is provided on the inner edge of one side of the third upper shell connecting plate. The upper shell latches on the inner edge of the other side of the second upper shell connecting plate are embedded in the upper shell through-holes on the inner edge of one side of the third upper shell connecting plate, and the second upper shell connecting plate is fixedly spliced to the third upper shell connecting plate; A plurality of upper shell latches are provided on the inner edge of the other side of the third upper shell connecting plate, and an upper shell through-hole matching the upper shell latches on the inner edge of one side of the third upper shell connecting plate is provided on the inner edge of one side of the fourth upper shell connecting plate. The upper shell latches on the inner edge of the other side of the third upper shell connecting plate are embedded in the upper shell through-holes on the inner edge of one side of the fourth upper shell connecting plate, and the third upper shell connecting plate is fixedly spliced to the fourth upper shell connecting plate; A plurality of upper shell latches are provided on the inner edge of the other side of the fourth upper shell connecting plate. The upper shell latches on the inner edge of the other side of the fourth upper shell connecting plate are embedded in the upper shell through holes on the inner edge of the other side of the first upper shell connecting plate, and the fourth upper shell connecting plate is fixedly spliced to the first upper shell connecting plate; A plurality of pin holes are provided inside the upper shell connecting plate connecting piece. The upper shell pins of the first upper shell connecting plate, the second upper shell connecting plate, the third upper shell connecting plate and the fourth upper shell connecting plate are inserted into the pin holes inside the upper shell connecting plate connecting piece and spliced together to form an integral upper shell.