A portable screening device
The design of the portable screening device solves the problems of large size, high noise, difficult maintenance and screen clogging of existing screening devices, and provides a flexible and easy-to-maintain screening solution, improving screening efficiency and portability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANXI HONGAN EMERGENCY TECH CO LTD
- Filing Date
- 2025-04-10
- Publication Date
- 2026-05-29
AI Technical Summary
Existing screening devices are large in size, difficult to maintain, have high wear and tear, and are noisy. Furthermore, the screens are prone to clogging when screening wet materials, which is difficult to handle.
A portable screening device was designed, including an upper screen body, a lower screen body, a screen mesh, and a locking device. The screen mesh is set between the upper and lower screen bodies and is quickly connected by the locking device. Combined with screen meshes of various specifications and a flow guiding structure, flexible screening can be achieved.
It achieves a portable, low-noise, and easy-to-maintain screening process, preventing material burial and mixing, and improving screening efficiency and flexibility.
Smart Images
Figure CN224293852U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of mechanical technology, specifically to a portable screening device. Background Technology
[0002] A screening device is a piece of equipment used for rapid on-site screening of materials. Its main function is to separate coarse and fine materials, and it is suitable for screening and grading powdery and granular materials. It is widely used in industries such as plastics, abrasives, chemicals, pharmaceuticals, metallurgy, building materials, grains, carbon, and fertilizers. For example, in the emergency rescue industry, positive pressure oxygen respirators require calcium hydroxide filling. To prevent calcium hydroxide powder from clumping and affecting breathing resistance and absorption, this device is needed to remove the calcium hydroxide powder. However, existing screening devices on the market have drawbacks such as large size, difficulty in maintenance, high wear and tear, and high noise. When screening wet materials using vibrating screens and linear screens, the screens are also prone to clogging and difficult to clean. Utility Model Content
[0003] This application addresses the aforementioned shortcomings of the prior art by providing a portable screening device to solve at least one of the aforementioned technical problems.
[0004] A portable screening device includes an upper screen body, a lower screen body, a screen mesh, and a locking device;
[0005] The upper screen body has a first opening on its top and / or side and at least one second opening on its bottom; the lower screen body is located below the upper screen body and has a third opening on its lower screen body corresponding to the position of the second opening.
[0006] At least one screen is detachably disposed between the second opening and the third opening, and the screen covers the second opening and the third opening so that the material falls into the lower screen after being screened by the screen in the upper screen body.
[0007] The locking device includes a first locking member disposed on the side of the upper screen body and a second locking member disposed on the side of the lower screen body; the first locking member is used to lock with the second locking member to connect the upper screen body and the lower screen body.
[0008] In some specific embodiments, a fixing frame and a fixing member are also included; a first auxiliary structure is provided on part or all of the edges of the inner sidewall of the upper screen body corresponding to the second opening, and / or a second auxiliary structure is provided on part or all of the edges of the inner sidewall of the lower screen body corresponding to the third opening.
[0009] The fastener passes through the fixing frame, the screen and the first auxiliary structure in sequence to fix the screen to the second opening; and / or the fastener passes through the fixing frame, the screen and the second auxiliary structure in sequence to fix the screen to the third opening.
[0010] In some specific embodiments, a gripper mechanism is also included; at least two gripper mechanisms are provided on the sides of the upper screen body and / or the lower screen body. Specifically, the gripper mechanisms may be provided on opposite sides in the horizontal direction.
[0011] In some specific embodiments, the first locking member includes a hook member, and the second locking member includes a hook member that cooperates with the hook; hook members are provided on opposite sides of the upper screen body, and hook members are provided on the lower screen body at positions corresponding to the upper screen body.
[0012] In some specific embodiments, a guide plate is provided protruding from the first opening on the side of the upper screen body; an inclined guide member is provided on at least one side edge of the guide plate, one end of the inclined guide member is connected to the edge of the first opening, and the other end is inclined in the direction of the first opening.
[0013] In one specific embodiment, by providing an outwardly protruding guide plate on the first opening and providing inclined guide members on both sides of the guide plate, with the end of the inclined guide member away from the first opening inclined in the direction of the first opening, the front end of the first opening can be narrowed.
[0014] In practical applications, screening devices have different purposes. For example, one scenario is to screen out coarse particles from an object and retain fine particles. In this case, the fine particles that fall into the lower screen body after screening are the material that needs to be retained and need to be carefully transferred. Another scenario is to screen out fine particles from a material and retain coarse particles. In this case, the coarse particles that remain in the upper screen body after screening are the material that needs to be retained and need to be carefully transferred. In this case, the guide plate and inclined guide component set on the first opening can effectively pour the material in the upper screen body out along the guiding direction of the guide plate.
[0015] In specific applications, a cover that mates with the first opening may also be included, used to open or close the first opening as needed. In one specific embodiment, after the material has been placed into the upper screen body through the first opening, the first opening can be closed by the cover before screening the material, which can prevent the material from scattering outwards due to shaking during the screening process.
[0016] It should be noted that this application does not specifically limit the guide plate and the inclined guide to a planar structure. Specifically, the guide plate and the inclined guide can be a curved structure. The material can enter and exit the upper screen body more smoothly through the curved structure and will not get stuck in the dead corner of the structure.
[0017] In some specific embodiments, the screens have various specifications, with different mesh counts and / or screen hole shapes. The screen holes include circular, elliptical, rectangular, polygonal, and / or irregularly shaped holes. By setting screens of various specifications, materials of different particle sizes can be filtered. In practical applications, users can select screens with different mesh counts and different screen hole shapes to filter materials according to their actual needs.
[0018] In some specific embodiments, the internal height of the upper screen body is greater than or equal to the internal height of the lower screen body.
[0019] In one specific embodiment, by setting the upper and lower screen bodies to have different heights, the internal space of the upper screen body can be larger than that of the lower screen body. During the screening process of the shaking screening device, the larger internal space of the upper screen body can accommodate a larger amount of material, thereby increasing the processing capacity per unit time of the device.
[0020] Furthermore, the larger internal space of the upper screen body allows the material to form a thicker material layer during its descent, utilizing the difference in gravity to achieve initial separation of coarse and fine particles. It also extends the residence time of the material inside the upper screen body, increases the probability of collision between particles, and promotes the efficiency of fine particles passing through the screen holes.
[0021] In some specific embodiments, a sloping guide area is formed at the bottom of the lower screen body, and a discharge port is provided at the lowest point of the sloping guide area; the discharge port is used to connect to an external material processing device to discharge the material in the sloping guide area from the discharge port.
[0022] In some specific embodiments, the upper screen body includes a box structure, with a first opening disposed on one side of the box structure in the horizontal direction; gripper mechanisms are respectively symmetrically disposed on opposite sides of the box structure in the horizontal direction with respect to the first opening.
[0023] In some specific embodiments, a screen installation mechanism is also included; the screen installation mechanism is provided with at least one installation groove for installing the screen; both ends of the screen installation mechanism are respectively provided with slots for engaging with the second opening and the third opening, so that the screen installation mechanism is connected to the second opening at one end through the slots and to the third opening at the other end.
[0024] In one specific embodiment, the screen mounting mechanism is provided with multiple mounting grooves, allowing multiple layers of screens of different specifications to be installed simultaneously within the mechanism. This enables materials to undergo multi-layer screening through screens of varying specifications. In practical applications, the mounting grooves can be a chute structure, allowing users to quickly replace different layers of screens according to their specific needs.
[0025] Beneficial Effects: This application provides a portable screening device, including an upper screen body, a lower screen body, a screen mesh, and a locking device. By setting corresponding upper and lower screen bodies, and detachably installing at least one layer of screen mesh between the second opening of the upper screen body and the third opening of the lower screen body, users can flexibly adjust the specifications and quantity of the screen mesh according to their own needs. The locking device allows for quick locking of the upper and lower screen bodies. The overall structure is simple, with high strength, and the screening process is more intuitive, facilitating the screening of small quantities of materials. It can prevent materials from being buried, vibrating, or mixing during the screening process. The operation is stable and reliable, with low noise and convenient maintenance. Attached Figure Description
[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of a three-dimensional structure according to this application;
[0028] Figure 2 This is a schematic diagram of a three-dimensional installation structure according to this application;
[0029] Figure 3 This is a three-dimensional structural diagram of the upper sieve body in this application;
[0030] Figure 4 This is a front view structural diagram of the upper sieve body in this application;
[0031] Figure 5 This is a side view structural diagram of this application;
[0032] Figure 6 This is a top view of one of the structures in this application;
[0033] Figure 7 This is a top view of the fixed frame structure in this application;
[0034] Figure 8 This is a schematic diagram of another three-dimensional structure of the upper sieve body in this application;
[0035] Figure 9 This is a schematic diagram of a three-dimensional installation structure with a screen installation mechanism in this application;
[0036] Figure 10 This is a three-dimensional structural diagram of the lower screen body with a discharge port in this application.
[0037] The attached figures are labeled as follows: 1-Upper screen body; 11-First opening; 111-Guide plate; 112-Inclined guide; 12-Second opening; 121-First auxiliary structure; 2-Lower screen body; 21-Third opening; 211-Second auxiliary structure; 22-Discharge port; 3-Screen; 31-Screen hole; 4-Locking device; 41-First locking element; 42-Second locking element; 51-Fixing frame; 52-Fixing element; 6-Handling mechanism; 7-Screen installation mechanism; 71-Installation groove; 72-Card slot. Detailed Implementation
[0038] The following will clearly and completely describe the concept, specific structure and technical effects of this application in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, features and effects of this application.
[0039] Various embodiments of this application will be described more fully below. This application may have various embodiments, and adjustments and changes may be made therein. However, it should be understood that there is no intention to limit the various embodiments of this application to the specific embodiments disclosed herein, but rather this application should be understood to cover all adjustments, equivalents, and / or alternatives falling within the spirit and scope of the various embodiments of this application.
[0040] In the following, the terms “comprising” or “may include” as used in the various embodiments of this application indicate the presence of the disclosed functions, operations, or elements, and do not limit the addition of one or more functions, operations, or elements. Furthermore, as used in the various embodiments of this application, the terms “comprising,” “having,” and their cognates are intended only to indicate a particular feature, number, step, operation, element, component, or combination of the foregoing, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing, or the possibility of adding one or more combinations of features, numbers, steps, operations, elements, components, or combinations of the foregoing.
[0041] In various embodiments of this application, the expression "or" or "at least one of A and / or B" includes any combination or all combinations of the words listed simultaneously. For example, the expression "A or B" or "at least one of A and / or B" may include A, may include B, or may include both A and B.
[0042] The terms used in the various embodiments of this application (such as "first," "second," etc.) may modify various constituent elements in various embodiments, but do not limit the corresponding constituent elements. For example, the above terms do not limit the order and / or importance of the elements. The above terms are only used for the purpose of distinguishing one element from other elements. For example, a first user device and a second user device refer to different user devices, although both are user devices. For example, without departing from the scope of the various embodiments of this application, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.
[0043] It should be noted that, in this application, unless otherwise explicitly specified and defined, terms such as "installation," "connection," and "fixation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0044] In this application, those skilled in the art should understand that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings and are only for the purpose of describing this application 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, and therefore should not be construed as a limitation of this application.
[0045] The terminology used in the various embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the various embodiments of this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of this application pertain. The terms (such as those defined in a generally used dictionary) are to be interpreted as having the same meaning as in the context of the relevant technical field and are not to be interpreted as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of this application.
[0046] Example 1
[0047] This embodiment provides a portable screening device, the specific solution of which is as follows:
[0048] A portable screening device includes an upper screen body 1, a lower screen body 2, a screen 3, and a locking device 4;
[0049] The upper screen body 1 has a first opening 11 on its top and / or side and at least one second opening 12 on its bottom; the lower screen body 2 is located below the upper screen body 1 and has a third opening 21 on its lower screen body 2 corresponding to the position of the second opening 12.
[0050] At least one layer of screen 3 is detachably disposed between the second opening 12 and the third opening 21, and the screen 3 covers the second opening 12 and the third opening 21 so that the material falls into the lower screen 2 after being screened by the screen 3 in the upper screen body 1.
[0051] The locking device 4 includes a first locking member 41 disposed on the side of the upper screen body 1 and a second locking member 42 disposed on the side of the lower screen body 2; the first locking member 41 is used to lock with the second locking member 42 to connect the upper screen body 1 and the lower screen body 2, such as... Figure 1 and Figure 2 As shown, specifically, the first locking element 41 and the second locking element 42 are detachably connected.
[0052] In some specific embodiments, such as Figure 3 and Figure 7 As shown, it also includes a fixed frame 51 and a fastener 52; a first auxiliary structure 121 is provided on part or all of the edges of the inner wall of the upper screen body 1 corresponding to the second opening 12, and / or a second auxiliary structure 211 is provided on part or all of the edges of the inner wall of the lower screen body 2 corresponding to the third opening 21.
[0053] The fastener 52 passes through the fixing frame 51, the screen 3 and the first auxiliary structure 121 in sequence to fix the screen 3 on the second opening 12; and / or the fastener 52 passes through the fixing frame 51, the screen 3 and the second auxiliary structure 211 in sequence to fix the screen 3 on the third opening 21.
[0054] In practical applications, the first auxiliary structure 121 is arranged along the entire edge of the inner wall of the upper screen body 1 corresponding to the second opening 12, and the shape of the first auxiliary structure 121 is matched with the edge shape of the fixing frame 51. In a specific embodiment, the fixing member 52 is a bolt, and the first auxiliary structure 121 and the fixing frame 51 are respectively provided with openings 53 for matching the bolt. By aligning the openings 53 on the first auxiliary structure 121 and the fixing frame 51, the bolt can better fix the fixing frame 51 and the first auxiliary structure 121.
[0055] In some specific embodiments, a gripper mechanism 6 is also included; at least two gripper mechanisms 6 are provided on the sides of the upper screen body 1 and / or the lower screen body 2. Specifically, the gripper mechanisms 6 may be respectively provided on opposite sides 6 in the horizontal direction of the upper screen body 1 and / or the lower screen body 2.
[0056] In practical applications, by setting up a corresponding gripper mechanism 6, it is possible to manually hold the gripper mechanism 6 and perform screening and filtering. This is suitable for filtering small amounts of materials. By manually filtering and screening, the force of the material passing through the screen 3 can be flexibly controlled, and the filtering can be performed more intuitively.
[0057] In some specific embodiments, the first locking member 41 includes a hook member, and the second locking member 42 includes a hook member that cooperates with the hook; hook members are provided on opposite sides of the upper screen body 1, and hook members are provided on the lower screen body 2 at positions corresponding to the upper screen body 1.
[0058] In practical applications, users can quickly combine and disassemble the fasteners and hooks to achieve a detachable connection between the upper screen body 1 and the lower screen body 2.
[0059] In some specific embodiments, a guide plate 111 protrudes from the first opening 11 on the side of the upper screen body 1; an inclined guide member 112 is provided on at least one side edge of the guide plate 111, one end of the inclined guide member 112 is connected to the edge of the first opening 11, and the other end is inclined in the direction of the first opening 11.
[0060] In one specific embodiment, such as Figure 4 , Figure 5 and Figure 6 As shown, by providing an outwardly protruding guide plate 111 on the first opening 11, and providing inclined guide members 112 on both sides of the guide plate 111, and the end of the inclined guide member 112 away from the first opening 11 is inclined in the direction of the first opening 11, the front end of the first opening 11 can be narrowed.
[0061] In practical applications, screening devices have different purposes. For example, one case is to screen out coarse particles from an object and retain fine particles. In this case, the fine particles that fall into the lower screen body 2 after screening are the materials that need to be retained and need to be carefully transferred. Another case is to screen out fine particles from a material and retain coarse particles. In this case, the coarse particles that fall into the upper screen body 1 after screening are the materials that need to be retained and need to be carefully transferred. In this case, the guide plate 111 and the inclined guide member 112 set on the first opening 11 can effectively pour the material in the upper screen body 1 out along the guiding direction of the guide plate 111.
[0062] In specific applications, users can choose the location of the first opening 11 according to their own needs. It can be set only at the top of the upper screen body 1, such as... Figure 8As shown. Furthermore, it may also include a cover that mates with the first opening 11, used to open or close the first opening 11 according to the actual application. In one specific embodiment, after the material has been placed into the upper screen body 1 through the first opening 11, the first opening 11 can be closed by the cover before screening the material, which can prevent the material from scattering outwards due to shaking during the screening process.
[0063] It should be noted that this application does not specifically limit the guide plate 111 and the inclined guide 112 to a planar structure. Specifically, the guide plate 111 and the inclined guide 112 can be a curved structure. The material can enter and exit the upper screen body 1 more smoothly through the curved structure and will not get stuck in the dead corner of the structure.
[0064] In some specific embodiments, the screen 3 has various specifications, with different mesh counts and / or screen hole shapes. The screen holes 31 on the screen 3 include circular screen holes 31, and / or elliptical screen holes 31, and / or rectangular screen holes 31, and / or polygonal screen holes 31, and / or irregularly shaped screen holes 31. By setting screens 3 of various specifications, materials of different particle sizes can be filtered. In practical applications, users can select screens 3 with different mesh counts and screen hole shapes 31 to filter materials according to actual needs.
[0065] In some specific embodiments, the internal height of the upper sieve body 1 is greater than or equal to the internal height of the lower sieve body 2.
[0066] In one specific embodiment, by setting the upper screen body 1 and the lower screen body 2 to have different heights, the internal space of the upper screen body 1 can be larger than that of the lower screen body 2. During the screening process of the shaking screening device, the larger internal space of the upper screen body 1 can accommodate a larger amount of material, thereby increasing the processing capacity of the device per unit time.
[0067] Furthermore, the larger internal space of the upper screen body 1 allows the material to form a thicker material layer during its descent, utilizing the difference in gravity to achieve initial separation of coarse and fine particles. It also extends the residence time of the material inside the upper screen body 1, increases the probability of collision between particles, and promotes the efficiency of fine particles passing through the screen holes 31.
[0068] In some specific embodiments, such as Figure 10 As shown, a sloping flow guiding area is formed at the bottom of the lower screen body 2, and a discharge port 22 is provided at the lowest point of the sloping flow guiding area; the discharge port 22 is used to connect to an external material processing device to discharge the material in the sloping flow guiding area from the discharge port 22.
[0069] In some specific embodiments, the upper screen body 1 includes a box structure, with a first opening 11 disposed on one side of the box structure in the horizontal direction; gripper mechanisms 6 are respectively symmetrically disposed on opposite sides of the box structure in the horizontal direction with respect to the first opening 11.
[0070] In some specific embodiments, such as Figure 9 As shown, it also includes a screen installation mechanism 7; the screen installation mechanism 7 is provided with at least one installation groove 71 for installing the screen 3; both ends of the screen installation mechanism 7 are respectively provided with slots 72 for engaging with the second opening 12 and the third opening 21, so that the screen installation mechanism 7 is connected to the second opening 12 at one end through the slots 72 and to the third opening 21 at the other end.
[0071] In one specific embodiment, the screen mounting mechanism 7 is provided with multi-layer mounting grooves 71. By providing multi-layer mounting grooves 71, multiple layers of screens 3 of different specifications can be simultaneously installed in the screen mounting mechanism 7. Thus, materials can be screened through multiple layers of screens 3 of different specifications. In practical applications, the mounting grooves 71 can be a chute structure, allowing users to quickly replace different layers of screens 3 according to different actual needs.
[0072] This embodiment provides a portable screening device, including an upper screen body, a lower screen body, a screen mesh, and a locking device. By setting corresponding upper and lower screen bodies, and detachably installing at least one layer of screen mesh between the second opening of the upper screen body and the third opening of the lower screen body, the user can flexibly adjust the specifications and quantity of the screen mesh according to their own needs. The locking device can quickly lock the upper and lower screen bodies together. The overall structure is simple, strong, and the screening process is more intuitive, facilitating the screening of small quantities of materials and preventing material burial, vibration, or mixing during the screening process.
[0073] The above is a detailed description of the preferred embodiments of this application. However, the invention of this application is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.
Claims
1. A portable screening device, characterized in that, It includes an upper screen body, a lower screen body, a screen, and a locking device; The upper screen body has a first opening on its top and / or side and at least one second opening on its bottom; the lower screen body is located below the upper screen body and has a third opening on its lower screen body corresponding to the position of the second opening. At least one layer of the screen is detachably disposed between the second opening and the third opening, the screen covering the second opening and the third opening, so that the material falls into the lower screen after being screened by the screen in the upper screen body; The locking device includes a first locking member disposed on the side of the upper screen body and a second locking member disposed on the side of the lower screen body; the first locking member is used to lock with the second locking member to connect the upper screen body and the lower screen body.
2. The portable screening device according to claim 1, characterized in that, It also includes a fixing frame and fixing components; a first auxiliary structure is provided on part or all of the edges of the inner wall of the upper screen body corresponding to the second opening, and / or a second auxiliary structure is provided on part or all of the edges of the inner wall of the lower screen body corresponding to the third opening; The fastener passes sequentially through the fixing frame, the screen, and the first auxiliary structure to fix the screen to the second opening; And / or the fastener passes sequentially through the fixing frame, the screen and the second auxiliary structure to fix the screen to the third opening.
3. The portable screening device according to claim 1, characterized in that, It also includes gripper mechanisms; at least two gripper mechanisms are provided on the sides of the upper screen body and / or the lower screen body.
4. The portable screening device according to claim 1, characterized in that, The first locking component includes a hook component, and the second locking component includes a hook component that cooperates with the hook; The hooks are provided on opposite sides of the upper screen body, and the buckles are provided on the lower screen body at the positions corresponding to the upper screen body.
5. A portable screening device according to claim 1, characterized in that, A guide plate is provided protruding from the first opening located on the side of the upper screen body; An inclined guide is provided on at least one edge of the guide plate, one end of which is connected to the edge of the first opening, and the other end is inclined in the direction of the first opening.
6. A portable screening device according to claim 1, characterized in that, The screen has various specifications, and the mesh count and / or screen hole shape of the screens of different specifications are different; The screen mesh includes circular screen mesh, and / or elliptical screen mesh, and / or rectangular screen mesh, and / or polygonal screen mesh, and / or irregularly shaped screen mesh.
7. A portable screening device according to claim 1, characterized in that, The internal height of the upper sieve body is greater than or equal to the internal height of the lower sieve body.
8. A portable screening device according to claim 1, characterized in that, The bottom of the lower screen body has a sloping flow guiding area, and a discharge port is opened at the lowest point of the sloping flow guiding area; The discharge port is used to connect to an external material handling device to discharge the material in the inclined guide area from the discharge port.
9. A portable screening device according to claim 3, characterized in that, The upper screen body includes a box structure, and the first opening is disposed on one side of the box structure in the horizontal direction; The gripper mechanisms are respectively symmetrically arranged on opposite sides of the box structure in the horizontal direction with respect to the first opening.
10. A portable screening device according to claim 1, characterized in that, It also includes a screen installation mechanism; the screen installation mechanism is provided with at least one installation groove for installing the screen; The screen installation mechanism is provided with slots at both ends for engaging with the second opening and the third opening, so that the screen installation mechanism is connected to the second opening at one end and to the third opening at the other end through the slots.