A side-hung very narrow casement window
By arranging the lock body and lock cylinder within the window frame and combining them with bevel gear transmission and a detachable folding screen, the problems of wide traditional handle frames and difficulty in disassembling fixed screens are solved, maximizing the visible glass area and simplifying operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUANGSHAN ANKANG NEW TYPE BUILDING MATERIALS CO LTD
- Filing Date
- 2025-08-05
- Publication Date
- 2026-07-14
AI Technical Summary
Traditional handles installed on the frame surface result in wide frame edges and a small visible glass area. Furthermore, some integrated screens are fixed structures, making disassembly difficult and causing inconvenience for cleaning and maintenance.
An ultra-narrow outward-opening window with a handle mounted on the side was designed. The lock body and lock cylinder are concealed within the window frame. Combined with a bevel gear transmission structure and a detachable folding screen, the visible glass area is maximized, and operation is simplified through a flip-lock and elastic reset structure.
It effectively reduces the width of the frame, increases the visible area of the glass, simplifies the operation of the screen window, provides convenient cleaning and maintenance, and enhances the user experience.
Smart Images

Figure CN224496221U_ABST
Abstract
Description
Technical Field
[0001] This utility model mainly relates to the field of door and window technology, specifically an ultra-narrow outward-opening window with a handle mounted on the side. Background Technology
[0002] Doors and windows are building enclosure components used to separate indoor and outdoor spaces or different areas. They not only fulfill basic functions such as lighting, ventilation, heat insulation, and sound insulation, but also influence the overall aesthetics and user experience of a building through the design of materials, shapes, and opening methods. They typically consist of a window frame, window sash, glass, and hardware accessories (such as hinges and handles). The window frame is fixed to the building structure, while the window sash is connected to the window frame through hardware to open or close, thereby regulating indoor and outdoor air circulation and light entry.
[0003] Side-mounted, ultra-narrow outward-opening windows use extremely narrow profiles as the frame and sash, minimizing the obstruction of the view by the frame and enhancing natural light and the sense of spaciousness. The outward-opening design means the window sash pushes open to the outside, without taking up interior space, making it suitable for small apartments or spaces requiring high space utilization. However, traditional handles are mounted on the frame surface, resulting in a wider frame and thus reducing the visible glass area. While some integrated screen windows offer opening options, these screens are mostly fixed, making disassembly difficult and causing inconvenience for cleaning and maintenance. Utility Model Content
[0004] This utility model addresses the problem of overly simplistic existing technical solutions by providing an extremely narrow outward-opening window with a side-mounted handle. This solves the problems mentioned in the background section, such as the traditional handle being installed on the frame surface, resulting in a wide frame edge and a small visible glass area. Furthermore, some integrated screen windows have fixed screen structures, making disassembly difficult and causing inconvenience for cleaning and maintenance.
[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:
[0006] An ultra-narrow outward-opening window with a side-mounted handle includes a frame, an upper horizontal fixed window frame, a lower vertical fixed window frame, and a lower vertical movable window frame. The upper horizontal fixed window frame and the lower vertical fixed window frame are fixed to the inner wall of the frame, and the top of the lower vertical fixed window frame is fixedly connected to the bottom of the upper horizontal fixed window frame. One end of the lower vertical movable window frame is rotatably connected to one side of the frame via a damping hinge, and the bottom is slidably connected to the corresponding position on the frame surface via a sliding hinge. The other end is engaged with the lower vertical fixed window frame via a side-mounted handle assembly. The outer end of the lower vertical movable window frame is equipped with a detachable folding screen. One end of the outer wall of the detachable folding screen is equipped with a locking tongue slider. The outer wall of the lower vertical fixed window frame profile is rotatably connected with a flip-up buckle at the position corresponding to the locking tongue slider.
[0007] The side-mounted handle assembly includes a lock body and a lock cylinder. The lock body is rotatably connected to a first bevel gear and a second bevel gear. One end of the second bevel gear is provided with a gear coaxial with it. A rack meshes with the gear above the gear, and a guide rod is provided above the rack.
[0008] Furthermore, the lock body is bolted to a concave area on the surface of the lower vertical movable window frame profile, and the lock cylinder is bolted to a concave mounting area on the surface of the lower vertical fixed window frame profile, opposite to the lock body. The openings of the concave areas of the two are opposite each other, forming a locking space for the lock body and the lock cylinder to cooperate.
[0009] Furthermore, the first bevel gear and the second bevel gear are vertically distributed and mesh with each other. A handle coaxially connected to the first bevel gear is provided on the surface of the lower vertical movable window frame profile and on the side symmetrical to the lock body installation plane. The handle is spaced a certain distance from the tempered glass between the inner wall of the lower vertical movable window frame and the glass.
[0010] Furthermore, a lock head is fixed to one end of the rack, and symmetrically distributed sliders are fixed to the top of the rack. The guide rod passes through the sliders, and a tension spring is provided above the two sliders. One end of the tension spring is fixedly connected to one of the sliders, and the other end is fixedly connected to the inner wall of the lock body. The rack forms a transmission structure through gears and an elastic reset structure through the tension springs. At the same time, a through groove is opened on one side of the lock body corresponding to the lock cylinder for the sliding extension and retraction of the lock head.
[0011] Furthermore, the folding screen includes a guide rail and a fixing frame. The bottom and top of the fixing frame are respectively engaged with the limiting slots set at corresponding positions on the frame to form an interlocking connection. A spring is fixed in the slot at the top of the frame, and the bottom end of the spring is tightly attached to the top of the fixing frame.
[0012] Furthermore, a metal mesh is provided between the guide rail frame and the fixed frame. The metal mesh is composed of upper and lower skeletons and a flexible rigid mesh in the middle. The upper and lower skeletons are constant force spring plates. A roller is rotatably installed inside the fixed frame. The front end of the metal mesh is fixedly connected to one side of the guide rail frame, and the innermost end is fixedly connected to the surface of the roller. The remaining part of the metal mesh is wrapped around the outer wall of the roller in a coiled shape. At the same time, a strip-shaped groove is opened on the surface of the fixed frame for the metal mesh to extend and retract when it is unrolled or rolled up.
[0013] Furthermore, the locking tongue slider is installed on one side of the guide rail frame, and when the locking tongue slider slides horizontally with the guide rail frame, it contacts the circular edge of the flip buckle. The flip buckle forms a flipping mechanism through the horizontal movement of the locking tongue slider, and the flip buckle is engaged in the corresponding slot opened in the locking tongue slider.
[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0015] 1. This door and window design features a concealed layout by installing the lock body and cylinder in a recessed area. The handle is directly mounted on the inner wall of the window frame where the glass is located, avoiding the prominent problems of traditional structures and effectively reducing the width of the frame. At the same time, the bevel gear, gear, and rack transmission structure inside the side-mounted handle assembly is compactly adapted to the profile groove, making full use of space and significantly increasing the visible area of the glass while ensuring functionality. The side-mounted handle assembly drives the lock head to extend and retract through bevel gear transmission, and with the elastic reset structure of the tension spring, the opening and closing process is smooth and effortless, and can be completed with one hand.
[0016] 2. Folding screens provide protection without hindering airflow. The frame of the upper and lower constant force spring plates not only provides stable vertical support for the screen, ensuring it unfolds flat and wrinkle-free, but also uses its own elastic potential energy to assist in closing the screen. The flexible yet rigid mesh material ensures protective performance without affecting indoor lighting and air circulation. Furthermore, when unfolding, simply pull the guide rail horizontally, and the locking tongue slider will automatically lock with the flip-up buckle through progressive thrust transmission, requiring no additional complicated operations and can be completed with one hand. When closing, rotate the flip-up buckle to release the lock.
[0017] 3. The detachable structure of the folding screen provides convenience for daily maintenance. The fixing frame is connected to the frame by the bottom and top limiting slots, and the spring in the top slot can provide elastic cushioning during installation, reducing the difficulty of alignment. This structure allows users to easily clean, repair or replace the screen, avoiding the maintenance inconvenience caused by the difficulty of disassembling traditional fixed screens; finally, its unfolding and folding operation is simple and effortless.
[0018] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the main structure of this utility model;
[0020] Figure 2 This is a schematic diagram of the unfolded structure of the lower vertical movable window frame of this utility model;
[0021] Figure 3 This is a schematic diagram of a partial internal structure of the side-mounted handle assembly of this utility model;
[0022] Figure 4 This is a schematic diagram of the folding screen window structure of this utility model.
[0023] Numbering on the map:
[0024] 1. Frame; 2. Upper horizontal fixed window frame; 3. Lower vertical fixed window frame; 4. Lower vertical movable window frame; 5. Side-mounted handle assembly; 501. Lock body; 502. Lock cylinder; 503. First bevel gear; 504. Second bevel gear; 505. Gear; 506. Rack; 507. Lock head; 508. Guide rod; 6. Folding screen; 601. Guide rail frame; 602. Fixing frame; 603. Metal mesh; 7. Lock tongue slider; 8. Flip buckle. Detailed Implementation
[0025] To facilitate understanding of this utility model, a more comprehensive description of the utility model will be given below with reference to the accompanying drawings, which show several embodiments of the utility model. However, the utility model can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the disclosure of the utility model more thorough and comprehensive.
[0026] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.
[0027] Please refer to the appendix carefully. Figure 1-4 The window frame includes a frame 1, an upper horizontal fixed window frame 2, a lower vertical fixed window frame 3, and a lower vertical movable window frame 4. The upper horizontal fixed window frame 2 and the lower vertical fixed window frame 3 are fixed to the inner wall of the frame 1, and the top of the lower vertical fixed window frame 3 is fixedly connected to the bottom of the upper horizontal fixed window frame 2. One end of the lower vertical movable window frame 4 is rotatably connected to one side of the frame 1 through a damping hinge, and the bottom is slidably connected to the corresponding position on the surface of the frame 1 through a sliding hinge. The other end is engaged with the lower vertical fixed window frame 3 through a side-mounted handle assembly 5. The outer end of the lower vertical movable window frame 4 is provided with a detachable folding screen 6. One end of the outer wall of the detachable folding screen 6 is provided with a locking tongue slider 7. The outer wall of the profile of the lower vertical fixed window frame 3 is rotatably connected with a flip buckle 8 corresponding to the position of the locking tongue slider 7.
[0028] The side-mounted handle assembly 5 includes a lock body 501 and a lock cylinder 502. The lock body 501 is rotatably connected to a first bevel gear 503 and a second bevel gear 504. One end of the second bevel gear 504 is provided with a gear 505 coaxial with it. A rack 506 meshes above the gear 505. A guide rod 508 is provided above the rack 506.
[0029] In this embodiment, as Figure 2As shown, the lock body 501 is bolted to the concave area on the surface of the lower vertical movable window frame 4 profile, and the lock cylinder 502 is bolted to the concave installation area on the side opposite to the lock body 501 on the surface of the lower vertical fixed window frame 3 profile. The openings of the concave areas of the two are opposite to each other, forming a locking space for the lock body 501 and the lock cylinder 502 to cooperate.
[0030] Through the above structure, the "concave" area provides a suitable mounting cavity for the lock body 501 and the lock cylinder 502, realizing the concealed layout of the two, avoiding protrusion from the profile surface and occupying extra space, effectively reducing the overall thickness of the window frame, and the locking space of the common components of the two provides a closed movement trajectory for the extension and retraction of the lock head 507.
[0031] In this embodiment, as Figure 3 As shown, the first bevel gear 503 and the second bevel gear 504 are vertically distributed and mesh with each other. The lower vertical movable window frame 4 profile surface and the side symmetrical to the lock body 501 are provided with a handle coaxially connected to the first bevel gear 503. The handle is a certain distance away from the tempered glass between it and the inner wall of the lower vertical movable window frame 4.
[0032] Through the above structure, the transmission components inside the lock body 501 can be fitted with the concave groove of the profile to achieve compact installation and make full use of space. The handle is directly installed on the inner wall of the window frame where the glass is located, rather than on the surface. Compared with the existing window frame, it can effectively reduce the width of the frame side. While ensuring the normal operation of the handle, it maximizes the preservation of the glass viewing area. This not only enhances the simplicity and aesthetics of the overall structure, but also improves the lighting effect and sense of openness of the door and window by maximizing the glass viewing area, thus achieving synergistic optimization of functionality and aesthetics.
[0033] In this embodiment, as Figure 3 As shown, a lock head 507 is fixed to one end of the rack 506, and symmetrically distributed sliders are fixed to the top of the rack 506. A guide rod 508 passes through the sliders, and a tension spring is provided above the two sliders. One end of the tension spring is fixedly connected to one of the sliders, and the other end is fixedly connected to the inner wall of the lock body 501. The rack 506 forms a transmission structure through the gear 505 and an elastic reset structure through the tension spring. At the same time, a through groove for the lock head 507 to slide and extend is opened through one side of the lock body 501 corresponding to the lock cylinder 502.
[0034] With the above structure, the guide rod 508 is fixed to the inner wall of the lock body 501, and its cooperation with the slider can ensure the smooth transmission of the rack 506. The elastic reset structure formed by the tension spring can drive the rack 506 and the lock head 507 to automatically reset after the transmission is completed, ensuring the reliable cooperation between the lock head 507 and the lock cylinder 502. All components work together to improve the durability of the side-mounted handle assembly 5.
[0035] In this embodiment, as Figure 4 As shown, the folding screen window 6 includes a guide rail frame 601 and a fixing frame 602. The bottom and top of the fixing frame 602 are respectively engaged with the limiting slots set at corresponding positions of the frame 1 to form an interlocking connection. A spring is fixed in the slot at the top of the frame 1, and the bottom end of the spring is tightly attached to the top of the fixing frame 602.
[0036] The detachable structure makes the folding screen window 6 easy to disassemble and reassemble, facilitating maintenance or replacement. The top spring provides elastic cushioning during installation. When the bottom of the fixing bracket 602 is inserted into the slot, the top spring can assist the top of the fixing bracket 602 to smoothly snap into the corresponding slot through its own elasticity, reducing the difficulty of alignment during installation and making the operation more effortless and convenient.
[0037] In this embodiment, as Figure 4 As shown, a metal mesh 603 is provided between the guide rail frame 601 and the fixed frame 602. The metal mesh 603 is composed of upper and lower skeletons and a flexible rigid mesh in the middle. The upper and lower skeletons are constant force spring plates. A roller is rotatably installed inside the fixed frame 602. The front end of the metal mesh 603 is fixedly connected to one side of the guide rail frame 601, and the innermost end is fixedly connected to the surface of the roller. The remaining part of the metal mesh 603 is wrapped around the outer wall of the roller. At the same time, the surface of the fixed frame 602 is provided with strip-shaped slots for the metal mesh 603 to extend and retract when it is unrolled or rolled up.
[0038] Through the above structure, the constant force spring sheet frame can provide stable vertical support, ensuring that the flexible rigid mesh is flat and wrinkle-free when unfolded, and can also use its own elastic potential energy to realize the automatic retraction of the mesh. The roller and winding structure make the space occupied by the mesh small after it is retracted. The overall structure not only takes into account the protective function and the convenience of operation, but also improves the space utilization rate and avoids the space occupied by traditional fixed screen windows around the window frame. It is especially suitable for the needs of extremely narrow outward opening windows for "narrow window frame and wide view".
[0039] In this embodiment, as Figure 4 As shown, the locking tongue slider 7 is installed on one side of the guide rail frame 601, and when the locking tongue slider 7 slides horizontally with the guide rail frame 601, it contacts the circular edge of the flip buckle 8. The flip buckle 8 forms a flipping mechanism through the horizontal movement of the locking tongue slider 7, and the flip buckle 8 is engaged in the corresponding slot opened in the locking tongue slider 7.
[0040] Through the above structure, by means of the circular edge contact of the flip-up buckle 8 and the continuous horizontal movement of the locking tongue slider 7, a gradual thrust transmission can be formed, so that the flip-up buckle 8 can be flipped under the action of force and finally locked into the slot, ensuring the continuity and smoothness of the locking process. No additional complicated operation steps are required, and the unfolding and locking of the folding screen window 6 can be completed by one hand, which improves the convenience of use.
[0041] The specific operating procedure of this utility is as follows: In the initial state, the lower vertical movable window frame 4 and the lower vertical fixed window frame 3 are locked. In the side-mounted handle assembly 5, the lock head 507 inside the lock body 501 extends out of the lock body 501 and is inserted into the slot of the lock cylinder 502. The two are fixed by mechanical locking.
[0042] When the lower vertical movable window frame 4 needs to be opened, operate the handle of the side-mounted handle assembly 5 and push the handle outward to drive the first bevel gear 503, which is coaxially connected to it, to rotate synchronously. The second bevel gear 504, which meshes with it, rotates counterclockwise with the rotation of the first bevel gear 503, while the gear 505, which is coaxially set at one end, rotates in the same direction. Under the rotation of the gear 505, the rack 506 moves horizontally along the guide rod 508, thereby driving the lock head 507 at one end of the rack 506 to move synchronously. This causes the lock head 507, which was originally inserted into the slot of the lock cylinder 502, to disengage from the slot and retract into the lock body 501. At this time, the locking state between the lower vertical movable window frame 4 and the lower vertical fixed window frame 3 is released. Subsequently, the lower vertical movable window frame 4 can rotate around the damping hinge connected to the frame 1 and push outward to achieve free opening and closing. The casement window-specific sliding hinge used at its bottom can provide rigid support according to the opening angle.
[0043] If the folding screen window 6 is to be used, the guide rail 601 can be pulled horizontally. Since the folding screen window 6 is detachably assembled with the corresponding slots of the frame 1 through the top and bottom of the fixing frame 602, the limiting structure of the slot forms a stable constraint on the fixing frame 602, effectively preventing it from shifting during the pulling of the guide rail 601. The top and bottom walls of the guide rail 601 slide smoothly against the guide structure at the corresponding position of the frame 1.
[0044] During this process, the guide rail 601 drives the metal mesh 603 fixed thereto to move synchronously, so that the metal mesh 603 wound on the surface of the roller gradually extends out from the strip-shaped slot on the surface of the fixed frame 602 and unfolds. The upper and lower skeletons (constant force spring plates) of the metal mesh 603 are stretched as the mesh unfolds. Because the constant force spring plates have constant elasticity characteristics, they can store elastic potential energy during the stretching process, and at the same time form vertical support for the flexible rigid mesh, ensuring that the flexible rigid mesh is flat and wrinkle-free.
[0045] As the guide rail 601 moves, the locking tongue slider 7 on one side slides horizontally in sync. When the locking tongue slider 7 moves to the position of the flip buckle 8, its front end contacts the circular edge of the flip buckle 8. As the locking tongue slider 7 continues to push, the flip buckle 8 will rotate around its axis of rotation with the frame 1 under the action of force until it engages with the slot of the locking tongue slider 7, thus locking the position of the guide rail 601. At this time, the metal mesh 603 is fully unfolded to form a protective barrier.
[0046] When the folding screen 6 needs to be retracted, rotate and flip the buckle 8 to disengage it from the slot of the locking tongue slider 7, releasing the lock on the guide rail frame 601. At this time, the constant force spring plates of the upper and lower frames of the metal screen 603 release the stored elastic potential energy, causing the metal screen 603 to retract towards the roller and be wound around the surface of the roller. The guide rail frame 601 is reset horizontally under the pull of the metal screen 603 until it fits against one side of the fixing frame 602, completing the retraction of the metal screen 603.
[0047] The present invention has been described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.
Claims
1. A side-mounted, extremely narrow outward-opening window, comprising a frame (1), an upper horizontal fixed window frame (2), a lower vertical fixed window frame (3), and a lower vertical movable window frame (4), characterized in that: The upper horizontal fixed window frame (2) and the lower vertical fixed window frame (3) are fixed to the inner wall of the frame (1), and the top of the lower vertical fixed window frame (3) is fixedly connected to the bottom of the upper horizontal fixed window frame (2). One end of the lower vertical movable window frame (4) is rotatably connected to one side of the frame (1) through a damping hinge, and the bottom is slidably connected to the corresponding position on the surface of the frame (1) through a sliding hinge. The other end is engaged with the lower vertical fixed window frame (3) through a side-mounted handle assembly (5). The lower vertical movable window frame (4) is provided with a detachable folding screen (6) at the outer end. The detachable folding screen (6) is provided with a locking tongue slider (7) at one end of the outer wall of the outer wall. The lower vertical fixed window frame (3) is rotatably connected with a flip buckle (8) at the position corresponding to the locking tongue slider (7). The side-mounted handle assembly (5) includes a lock body (501) and a lock cylinder (502). The lock body (501) is rotatably connected to a first bevel gear (503) and a second bevel gear (504). One end of the second bevel gear (504) is provided with a gear (505) coaxial with it. A rack (506) meshes above the gear (505). A guide rod (508) is provided above the rack (506).
2. The extremely narrow outward-opening window with a handle mounted on the side according to claim 1, characterized in that: The lock body (501) is bolted to the concave area on the profile surface of the lower vertical movable window frame (4), and the lock cylinder (502) is bolted to the concave installation area on the side opposite to the lock body (501) of the profile surface of the lower vertical fixed window frame (3). The openings of the concave areas of the two are opposite to each other, forming a locking space for the lock body (501) and the lock cylinder (502) to cooperate.
3. The extremely narrow outward-opening window with a side-mounted handle according to claim 1, characterized in that: The first bevel gear (503) and the second bevel gear (504) are vertically distributed and mesh with each other. The lower vertical movable window frame (4) profile surface and the side of the mounting symmetrical surface with the lock body (501) are provided with a handle coaxially connected to the first bevel gear (503). The handle is a certain distance away from the tempered glass between it and the inner wall of the lower vertical movable window frame (4).
4. The extremely narrow outward-opening window with a handle mounted on the side according to claim 1, characterized in that: One end of the rack (506) is fixed with a lock head (507), and the top of the rack (506) is fixed with symmetrically distributed sliders. The guide rod (508) passes through the sliders. A tension spring is provided above the two sliders. One end of the tension spring is fixedly connected to one of the sliders, and the other end is fixedly connected to the inner wall of the lock body (501). The rack (506) forms a transmission structure through the gear (505) and forms an elastic reset structure through the tension spring. At the same time, the lock body (501) has a through slot on one side of the corresponding lock cylinder (502) for the sliding extension and retraction of the lock head (507).
5. The extremely narrow outward-opening window with a handle mounted on the side according to claim 1, characterized in that: The folding screen window (6) includes a guide rail frame (601) and a fixing frame (602). The bottom and top of the fixing frame (602) are respectively engaged with the limiting slots set at the corresponding positions of the frame (1) to form an insertion connection. A spring is fixed in the slot at the top of the frame (1), and the bottom end of the spring is tightly attached to the top of the fixing frame (602).
6. The extremely narrow outward-opening window with a handle mounted on the side according to claim 5, characterized in that: A metal mesh (603) is provided between the guide rail frame (601) and the fixed frame (602). The metal mesh (603) is composed of upper and lower skeletons and a flexible rigid mesh in the middle. The upper and lower skeletons are constant force spring plates. A roller is rotatably arranged inside the fixed frame (602). The front end of the metal mesh (603) is fixedly connected to one side of the guide rail frame (601), and the innermost end is fixedly connected to the surface of the roller. The remaining part of the metal mesh (603) is wrapped around the outer wall of the roller. At the same time, a strip-shaped groove is opened on the surface of the fixed frame (602) for the metal mesh (603) to extend and retract when it is unrolled or rolled up.
7. The extremely narrow outward-opening window with a handle mounted on the side according to claim 1, characterized in that: The locking tongue slider (7) is installed on one side of the guide rail frame (601), and when the locking tongue slider (7) slides horizontally with the guide rail frame (601), it contacts the circular edge of the flip buckle (8). The flip buckle (8) forms a flipping mechanism through the horizontal movement of the locking tongue slider (7), and the flip buckle (8) is engaged in the corresponding slot of the locking tongue slider (7).