Telescopic helmet

Abstract

The utility model relates to the technical field of human body safety protection devices, in particular to a telescopic helmet which comprises a spherical crown-shaped top shell, at least one annular bottom shell and a telescopic structure. The outer diameter of the top shell is smaller than the inner diameter of the bottom shell, and the telescopic structure comprises a buckle and a sliding strip matched with the buckle; when the buckle loosens the sliding strip, the sliding strip can slide back and forth along the buckle so as to drive the top shell to retract into or extend out of the bottom shell; and when the sliding strip is clamped by the buckle, the sliding strip cannot slide. Therefore, the telescopic helmet is internally provided with the telescopic structure for connecting the top shell and the bottom shell, and by utilizing the telescopic mechanism of the telescopic structure, the helmet can be ensured to be fully stretched into a complete protection form during use, so that the safety protection performance is ensured; when the helmet is not used, the size is reduced, and the helmet is in an overlapped compact state, so that the carrying portability and the storage convenience of the whole structure are greatly improved, and the diversified requirements of modern users on the helmet are met.

Description

Technical Field

[0001] This utility model relates to the field of human safety protective equipment technology, and in particular to a retractable helmet. Background Technology

[0002] With increasing awareness of personal safety, helmets, as essential safety equipment, are widely used in various fields such as cycling, motorcycle driving, and construction. However, traditional helmets are bulky and have a fixed structure, making them inconvenient to carry and taking up considerable space when stored, significantly reducing the user experience. Moreover, existing helmet designs primarily focus on safety performance, lacking flexible structural designs, and thus failing to meet the diverse needs of modern users. Utility Model Content

[0003] In view of this, the present invention proposes a retractable helmet, which aims to solve the problem of the fixed structure and lack of convenience of existing helmets.

[0004] This utility model discloses a retractable helmet, comprising a spherical top shell, at least one annular bottom shell, and a telescopic structure; one end of the telescopic structure is connected to the top shell, and the other end is connected to the bottom shell. The outer diameter of the top shell is smaller than the inner diameter of the bottom shell. The retractable helmet is a hollow structure, and the telescopic structure is disposed inside the retractable helmet. The telescopic structure includes a buckle and a sliding strip that cooperates with the buckle; when the buckle releases the sliding strip, the sliding strip can slide back and forth along the buckle to drive the top shell to retract into or extend out of the bottom shell; when the buckle engages the sliding strip, the sliding strip cannot slide.

[0005] In one possible implementation, the buckle includes an integrally formed frame and a spring piece. The frame has a through-type structure with an opening at the bottom. One end of the spring piece extends into the interior of the frame through the opening, and the other end of the spring piece is located on the outside of the frame. The frame is fitted onto the outside of the sliding strip, and the sliding strip can slide back and forth along the frame. A recess is provided on the side of the sliding strip facing the spring piece. When the other end of the spring piece drives one end of the spring piece out of the recess, the sliding strip can slide back and forth along the frame. When one end of the spring piece extends into the recess, the sliding strip cannot slide.

[0006] In one possible implementation, the buckle is fixedly connected to the top shell, one end of the sliding bar is fixedly connected to the bottom shell, and the other end of the sliding bar is slidably connected to the frame.

[0007] In one possible implementation, the retractable helmet includes three retractable structures, wherein two of the retractable structures are identical in structure and located at the front end inside the retractable helmet, the two retractable structures are separately arranged and symmetrically distributed from left to right, and the remaining retractable structure is located at the rear end inside the retractable helmet and is positioned between two of the retractable structures.

[0008] In one possible implementation, the sliding strips of two of the telescopic structures are arc-shaped strip structures, and the sliding strip of the remaining telescopic structure is an arc-shaped Y-shaped structure, with both forked ends of the arc-shaped Y-shaped structure connected to the bottom shell.

[0009] In one possible implementation, the retractable helmet further includes a locking structure comprising an integrally formed arcuate body and an outwardly flanged edge. The outwardly flanged edge is connected to the bottom of the arcuate body, and the top of the arcuate body is rotatably connected to the top shell. The bending direction of the arcuate body is consistent with the bending direction of the top shell and opposite to the bending direction of the outwardly flanged edge. The bottom shell is provided with a locking position that cooperates with the outwardly flanged edge. When the top shell retracts into the bottom shell, the outwardly flanged edge disengages from the locking position; when the top shell extends out of the bottom shell, the outwardly flanged edge engages with the locking position.

[0010] In one possible implementation, the retractable helmet includes four identical locking structures, which are evenly distributed inside the retractable helmet.

[0011] In one possible implementation, the bottom shell includes an annular first shell and a second shell, the first shell being located between the top shell and the second shell. The outer diameter of the top shell is smaller than the inner diameter of the first shell, and the outer diameter of the first shell is smaller than the inner diameter of the second shell. The buckle is fixedly connected to the top shell, and one end of the sliding strip is fixedly connected to the second shell. When the buckle releases the sliding strip, the sliding strip can slide back and forth along the buckle to cause the top shell to retract into the first shell, and the first shell to retract into the second shell; or to cause the top shell to extend out of the first shell, and the first shell to extend out of the second shell.

[0012] In one possible implementation, the locking structure includes a first locking part and a second locking part with identical structures. The first locking part is disposed between the top shell and the first shell, and its arc-shaped body is rotatably connected to the top shell. The first shell has a first locking position that engages with the outward flange of the first locking part. The second locking part is disposed between the first shell and the second shell, and its arc-shaped body is rotatably connected to the first shell. The second shell has a second locking position that engages with the outward flange of the second locking part. When the top shell retracts into the first shell and the first shell retracts into the second shell, the outward flange of the first locking part disengages from the first locking position, and simultaneously, the outward flange of the second locking part disengages from the second locking position. When the top shell extends out of the first shell and the first shell extends out of the second shell, the outward flange of the first locking part engages with the first locking position, and simultaneously, the outward flange of the second locking part engages with the second locking position.

[0013] In one possible implementation, the top shell and / or the bottom shell are provided with a sliding groove, and the sliding bar is disposed in the sliding groove and can slide back and forth along the sliding groove.

[0014] Compared with existing technologies, the beneficial effects of this utility model are as follows: A retractable helmet includes a dome-shaped top shell, at least one annular bottom shell, and a telescopic structure; one end of the telescopic structure is connected to the top shell, and the other end is connected to the bottom shell. The outer diameter of the top shell is smaller than the inner diameter of the bottom shell. The retractable helmet has a hollow structure, and the telescopic structure is disposed inside the retractable helmet. The telescopic structure includes a buckle and a sliding strip that cooperates with the buckle. When the buckle releases the sliding strip, the sliding strip can slide back and forth along the buckle to drive the top shell to retract or extend from the bottom shell; when the buckle engages the sliding strip, the sliding strip cannot slide. It can be seen that the retractable helmet has a telescopic structure connecting the top shell and the bottom shell inside. Utilizing the telescopic mechanism of this structure, the helmet can be fully extended into a complete protective form when in use, ensuring safety performance; when not in use, it shrinks in size and folds into a compact state, thereby greatly improving the overall portability and storage convenience of the structure, meeting the diverse needs of modern users for helmets. Attached Figure Description

[0015] Figure 1 This is a first structural schematic diagram of a retractable helmet provided in an embodiment of the present utility model;

[0016] Figure 2 This is a schematic diagram of the second structure of the retractable helmet provided in an embodiment of the present invention;

[0017] Figure 3 This is a structural disassembly diagram of the retractable helmet provided in an embodiment of the present utility model;

[0018] Figure 4 A schematic diagram of the structure of the sliding bar provided in an embodiment of this utility model;

[0019] Figure 5 A schematic diagram of the top shell provided in an embodiment of this utility model;

[0020] Figure 6 A first structural schematic diagram of the first shell, telescopic structure, and locking structure provided for an embodiment of the present utility model;

[0021] Figure 7 A second structural diagram showing the first shell, telescopic structure, and locking structure provided for an embodiment of this utility model;

[0022] Figure 8 A schematic diagram of the structure of the second shell provided in an embodiment of this utility model.

[0023] The annotations in the attached figures are explained as follows:

[0024] 10. Top shell; 20. First shell; 30. Second shell; 31. Second locking position; 41. Frame; 42. Spring piece; 43. Sliding bar; 431. Recessed position; 432. Moving area; 433. Protrusion; 4331. Wedge-shaped surface; 51. Arc-shaped body of the first locking part; 52. Outer flange of the first locking part; 61. Arc-shaped body of the second locking part; 62. Outer flange of the second locking part; 70. Slide groove. Detailed Implementation

[0025] The solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0026] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and sliding situation between the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] Please refer to Figure 1-3 As shown, this utility model proposes a retractable helmet, including a spherical top shell 10, at least one annular bottom shell, and a telescopic structure; one end of the telescopic structure is connected to the top shell 10, and the other end of the telescopic structure is connected to the bottom shell. The outer diameter of the top shell 10 is smaller than the inner diameter of the bottom shell. The retractable helmet has a hollow structure, and the telescopic structure is disposed inside the retractable helmet. The telescopic structure includes a buckle and a sliding strip 43 that cooperates with the buckle; when the buckle releases the sliding strip 43, the sliding strip 43 can slide back and forth along the buckle to drive the top shell 10 to retract into or extend out of the bottom shell; when the buckle engages the sliding strip 43, the sliding strip 43 cannot slide.

[0029] Specifically, the top shell 10 has a smaller outer diameter, while the bottom shell has a relatively larger inner diameter, ensuring that the top shell 10 can retract smoothly into the bottom shell, allowing for flexible changes in the size of the retractable helmet. When the helmet is extended, the spherical top shell 10 and the annular bottom shell work together to form a complete hemispherical or near-hemispherical protective structure, effectively wrapping the user's head and providing comprehensive safety protection. When the helmet is compressed, the top shell 10 and the bottom shell are flatly stacked, significantly reducing the overall thickness and volume of the helmet, making it convenient for users to carry and store. The overall structure of this retractable helmet is compact and aesthetically pleasing, with the telescopic structure located inside, which is the core component for realizing the helmet's telescopic function. A buckle can be fixedly connected to the top shell 10 or the bottom shell. When the buckle is not engaged with the sliding strip 43, the sliding strip 43 can slide back and forth along the buckle, thereby causing the top shell 10 to retract or extend synchronously into the bottom shell, allowing for free adjustment of the helmet size. Conversely, when the latch engages the sliding strip 43, the sliding strip 43 is securely fixed, and the helmet's current extended state is maintained to provide effective safety protection.

[0030] Compared with the prior art, the retractable helmet proposed in this embodiment has an internal telescopic structure connecting the top shell 10 and the bottom shell. By utilizing the telescopic mechanism of this telescopic structure, the helmet can be fully extended into a complete protective form when in use, ensuring safety and protection performance; when not in use, it shrinks in size and is folded into a compact state, thereby greatly improving the overall portability and storage convenience of the structure and meeting the diverse needs of modern users for helmets.

[0031] In some embodiments of this application, the buckle includes an integrally formed frame 41 and a spring piece 42. The frame 41 has a through-structure and an opening at the bottom. One end of the spring piece 42 extends into the interior of the frame 41 through the opening, and the other end of the spring piece 42 is located on the outside of the frame 41. The frame 41 is sleeved on the outside of the sliding strip 43, and the sliding strip 43 can slide back and forth along the frame 41. A recessed position 431 is provided on the side of the sliding strip 43 facing the spring piece 42. When the other end of the spring piece 42 drives one end of the spring piece 42 out of the recessed position 431, the sliding strip 43 can slide back and forth along the frame 41. When one end of the spring piece 42 extends into the recessed position 431, the sliding strip 43 cannot slide.

[0032] For details, please refer to Figure 4As shown, the spring piece 42 is set at an angle, with one end extending obliquely into the interior of the frame 41 from the opening at the bottom end of the frame 41, and the other end located on the outside of the frame 41 for the user to press with their finger. When the user presses the other end of the spring piece 42, one end of the spring piece 42 lifts up and exits from the recess 431, thereby releasing the locking state of the sliding bar 43, allowing the sliding bar 43 to slide back and forth along the frame 41. To prevent the sliding bar 43 from sliding out of the preset range, the frame 41 may also be provided with a plug structure to effectively limit the sliding bar 43. Preferably, the sliding bar 43 has a recessed area and a protrusion 433 on the side facing the spring piece 42. The recessed area is divided into a shorter recessed position 431 and a longer moving area 432 by the protrusion 433. The spring piece 42 is positioned corresponding to the recess 431 and can engage the sliding bar 43, thus fixing and locking the sliding bar 43 to prevent it from sliding. The longer moving area 432 serves as a relative displacement channel for the spring piece 42, ensuring that the spring piece 42 can smoothly engage when the sliding bar 43 slides back and forth without jamming it. When the sliding bar 43 slides forward, its protrusion 433 first passes over the spring piece 42 to unlock it. Then, as the sliding bar 43 continues to slide, the spring piece 42 moves in the opposite direction relative to the sliding bar 43, meaning their relative positions change. When the sliding bar 43 slides in the opposite direction, the spring piece 42 moves in the forward direction relative to the sliding bar 43 until the protrusion 433 approaches the spring piece 42. Then, the protrusion 433 of the sliding bar 43 pushes one end of the spring piece 42, allowing it to slide across the protrusion 433 into the recess 431, thus locking the sliding bar 43. Throughout the process, the forward and backward sliding of the slider 43 changes the relative positional relationship between the slider 43 and the spring piece 42, thereby achieving the locking and unlocking functions. In addition, the protrusion 433 has a wedge-shaped surface 4331 on the side facing the moving area 432, and one end of the spring piece 42 can more smoothly cross the recess 431 along the wedge-shaped surface 4331, thereby achieving reliable locking of the slider 43.

[0033] In some embodiments of this application, the buckle is fixedly connected to the top shell 10, one end of the sliding strip 43 is fixedly connected to the bottom shell, and the other end of the sliding strip 43 is slidably connected to the frame 41.

[0034] Specifically, fixing the buckle to the top shell 10 allows the buckle to be positioned above the retractable helmet, making it easy for the user to press the spring 42 with their fingers, which is in line with ergonomic design.

[0035] In some embodiments of this application, the retractable helmet includes three retractable structures, wherein two of the retractable structures have the same structure and are located at the front end inside the retractable helmet, the two retractable structures are separately arranged and symmetrically distributed from left to right, and the remaining retractable structure is located at the rear end inside the retractable helmet and is arranged in the middle position of two of the retractable structures.

[0036] Specifically, the retractable helmet features three telescopic structures: two symmetrically positioned at the front and a third offset at the rear, forming three parallel and evenly distributed sliding tracks. This layout effectively prevents interference between the sliding tracks of the three structures, ensuring smooth and stable telescopic movement. In contrast, two telescopic structures might be insufficient, leading to unstable telescopic performance; while four structures increase support points, symmetrical placement could cause interference between sliding tracks, and offset placement could be difficult due to space constraints. Therefore, the design of three parallel and evenly distributed telescopic structures achieves a good balance between sliding stability and space utilization, ensuring structural reliability while avoiding mechanical conflicts.

[0037] In some embodiments of this application, two of the sliding strips 43 of the telescopic structure are arc-shaped strip structures, and the remaining sliding strip 43 of the telescopic structure is an arc-shaped Y-shaped structure, with both forked ends of the arc-shaped Y-shaped structure connected to the bottom shell.

[0038] Specifically, the retractable helmet features two identical telescopic structures at the front, each with a fixed support point, ensuring overall stability. The rear has only one telescopic structure. To enhance load-bearing capacity, this structure employs an arc-shaped Y-shaped sliding bar 43. This Y-shaped structure has two branching fixing points, each connected to the bottom shell, effectively distributing stress and enhancing stability. This design overcomes the instability issue caused by having only one telescopic structure at the rear. The single rear telescopic structure, through the arc-shaped Y-shaped sliding bar 43, together with the two front telescopic structures, forms a reasonable mechanical support system, improving overall structural stability and ensuring precise and reliable telescopic movements.

[0039] In some embodiments of this application, the retractable helmet further includes a locking structure, which includes an integrally formed arc-shaped body and an outward flange. The outward flange is connected to the bottom of the arc-shaped body, and the top of the arc-shaped body is rotatably connected to the top shell 10. The bending direction of the arc-shaped body is consistent with the bending direction of the top shell 10 and opposite to the bending direction of the outward flange. The bottom shell is provided with a locking position that cooperates with the outward flange. When the top shell 10 is retracted into the bottom shell, the outward flange disengages from the locking position. When the top shell 10 extends out of the bottom shell, the outward flange engages with the locking position.

[0040] Specifically, the curvature of the locking structure is highly matched to that of the retractable helmet, ensuring a harmonious appearance after locking. The curved body is rotatably connected to the top shell 10, allowing it to rotate slightly and flexibly with the movement of the top shell 10 to better match the curved surface of the bottom shell and assist in the smooth engagement and disengagement of the outer flange. The engagement of the outer flange and the bottom shell works together to effectively lock and release. When the top shell 10 retracts into the bottom shell, the outer flange automatically disengages, and the locking structure is released, allowing the top shell 10 to extend and retract freely. When the top shell 10 extends out of the bottom shell, the outer flange accurately engages, achieving a secure lock and effectively preventing the top shell 10 from accidentally retracting, further ensuring the stability of the helmet in its current extended state. Overall, this locking structure not only ensures a reliable lock between the top shell 10 and the bottom shell but also ensures smoothness and flexibility in the locking action, significantly improving the safety and user experience of the retractable helmet.

[0041] In some embodiments of this application, the retractable helmet includes four identical locking structures, which are evenly distributed inside the retractable helmet.

[0042] Specifically, the four locking mechanisms are evenly distributed, ensuring more uniform force distribution during locking of the retractable helmet, effectively preventing wobbling or loosening, and significantly improving the overall stability and robustness of the structure. Two of the four locking mechanisms are located at the front and rear positions on the left side of the helmet, respectively, while the other two are located at the front and rear positions on the right side, forming a symmetrical locking layout. This layout effectively ensures a balanced distribution of locking force on both sides of the helmet, guaranteeing a secure and reliable helmet during use.

[0043] In some embodiments of this application, the bottom shell includes an annular first shell 20 and a second shell 30. The first shell 20 is located between the top shell 10 and the second shell 30. The outer diameter of the top shell 10 is smaller than the inner diameter of the first shell 20, and the outer diameter of the first shell 20 is smaller than the inner diameter of the second shell 30. The buckle is fixedly connected to the top shell 10, and one end of the sliding strip 43 is fixedly connected to the second shell 30. When the buckle releases the sliding strip 43, the sliding strip 43 can slide back and forth along the buckle to drive the top shell 10 to retract into the first shell 20, and the first shell 20 to retract into the second shell 30; or to drive the top shell 10 to extend out of the first shell 20, and the first shell 20 to extend out of the second shell 30.

[0044] For details, please refer to Figure 5-8As shown, this retractable helmet utilizes a three-layered, nested retractable mechanism by dividing the bottom shell into two annular structures: a first shell 20 and a second shell 30. The top shell 10, the first shell 20, and the second shell 30 are nested sequentially, with the radial dimensions increasing layer by layer. This design ensures smooth retraction while maintaining reasonable gaps between layers. Furthermore, the optimized design of the three-layered structure makes the helmet's overall outline more rounded and natural when extended, with its curvature better conforming to the curve of the human head, significantly improving wearing comfort and fit. It should be noted that if four or more layers are used, the overall helmet structure becomes more complex, significantly increasing the design difficulty of the retractable and locking mechanisms, and substantially raising costs. This would affect the helmet's reliability and market competitiveness.

[0045] In some embodiments of this application, the locking structure includes a first locking part and a second locking part with identical structures. The first locking part is disposed between the top shell 10 and the first shell 20. The arc-shaped body 51 of the first locking part is rotatably connected to the top shell 10. The first shell 20 is provided with a first locking position that cooperates with the outer flange 52 of the first locking part. The second locking part is disposed between the first shell 20 and the second shell 30. The arc-shaped body 61 of the second locking part is rotatably connected to the first shell 20. The second shell 30 is provided with a second locking position 31 that cooperates with the outer flange 62 of the second locking part. When the top shell 10 retracts into the first shell 20 and the first shell 20 retracts into the second shell 30, the outer flange 52 of the first locking part disengages from the first locking position, and at the same time, the outer flange 62 of the second locking part disengages from the second locking position 31. When the top shell 10 extends out of the first shell 20 and the first shell 20 extends out of the second shell 30, the outer flange 52 of the first locking part engages with the first locking position, and at the same time, the outer flange 62 of the second locking part engages with the second locking position 31.

[0046] Specifically, to complement the three-layer nested structural design, the retractable helmet can also be equipped with two sets of identical locking parts. These locking parts share the same structure as the aforementioned locking structure, including an integrally formed arc-shaped body and an outward-flared edge, with the outward-flared edge connected to the bottom of the arc-shaped body. The first locking part is located between the top shell 10 and the first shell 20, and the second locking part is located between the first shell 20 and the second shell 30. The arc-shaped body of each locking part is rotatably connected to the inner shell, and the outward-flared edge of each locking part tightly engages with a corresponding locking position on the outer shell, ensuring a secure lock on each shell layer and effectively improving the overall structural safety and reliability.

[0047] In some embodiments of this application, the top shell 10 and / or the bottom shell are provided with a sliding groove 70, and the sliding strip 43 is disposed in the sliding groove 70 and can slide back and forth along the sliding groove 70.

[0048] For details, please refer to Figure 5 As shown, the groove 70 provides a clear movement trajectory for the sliding bar 43, ensuring that the sliding bar 43 slides smoothly and accurately back and forth in a predetermined direction, avoiding deviation or jamming. The groove 70 works in conjunction with the buckle to effectively limit the sliding of the sliding bar 43, improving the sliding stability and smoothness of the telescopic structure.

[0049] The retractable helmet provided by this utility model adopts a three-layer stacked retractable structure, combined with a reasonable sliding and locking mechanism, to achieve smooth and stable retraction. Its design not only allows for flexible adjustment of the helmet's size, making it easy to carry and store, but also enhances wearing comfort and fit, improving the product's practicality and user experience while ensuring safety and protection.

[0050] It should be noted that the technical solutions of the various embodiments of this utility model can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0051] The above description is only a part or preferred embodiment of this utility model. Neither the text nor the drawings should limit the scope of protection of this utility model. All equivalent structural transformations made using the content of this utility model specification and drawings under the overall concept of this utility model, or direct / indirect applications in other related technical fields, are included within the scope of protection of this utility model.

Claims

1. A retractable helmet, characterized in that, The helmet comprises a crown-shaped top shell, at least one annular bottom shell, and a telescopic structure. One end of the telescopic structure is connected to the top shell, and the other end is connected to the bottom shell. The outer diameter of the top shell is smaller than the inner diameter of the bottom shell. The telescopic helmet is hollow, and the telescopic structure is located inside the helmet. The telescopic structure includes a buckle and a sliding strip that cooperates with the buckle. When the buckle releases the sliding strip, the sliding strip can slide back and forth along the buckle to retract or extend the top shell into the bottom shell. When the buckle engages the sliding strip, the sliding strip cannot slide.

2. A retractable helmet according to claim 1, characterized in that, The buckle includes an integrally formed frame and a spring piece. The frame has a through-type structure with an opening at the bottom. One end of the spring piece extends into the interior of the frame through the opening, and the other end of the spring piece is located on the outside of the frame. The frame is fitted onto the outside of the sliding strip, and the sliding strip can slide back and forth along the frame. A recess is provided on the side of the sliding strip facing the spring piece. When the other end of the spring piece drives one end of the spring piece out of the recess, the sliding strip can slide back and forth along the frame. When one end of the spring piece extends into the recess, the sliding strip cannot slide.

3. A retractable helmet according to claim 2, characterized in that, The buckle is fixedly connected to the top shell, one end of the sliding strip is fixedly connected to the bottom shell, and the other end of the sliding strip is slidably connected to the frame.

4. A retractable helmet according to claim 1, characterized in that, The retractable helmet includes three retractable structures, two of which have identical structures and are located at the front end inside the retractable helmet. The two retractable structures are separated and symmetrically distributed from left to right. The remaining retractable structure is located at the rear end inside the retractable helmet and is positioned between the two retractable structures.

5. A retractable helmet according to claim 4, characterized in that, Two of the sliding bars of the telescopic structure are arc-shaped strips, and the sliding bar of the remaining telescopic structure is an arc-shaped Y-shaped structure. Both forked ends of the arc-shaped Y-shaped structure are connected to the bottom shell.

6. A retractable helmet according to claim 1, characterized in that, The retractable helmet also includes a locking structure, which comprises an integrally formed arc-shaped body and an outwardly flanged edge. The outwardly flanged edge is connected to the bottom of the arc-shaped body, and the top of the arc-shaped body is rotatably connected to the top shell. The bending direction of the arc-shaped body is consistent with the bending direction of the top shell and opposite to the bending direction of the outwardly flanged edge. The bottom shell is provided with a locking position that cooperates with the outwardly flanged edge. When the top shell retracts into the bottom shell, the outwardly flanged edge disengages from the locking position; when the top shell extends out of the bottom shell, the outwardly flanged edge engages with the locking position.

7. A retractable helmet according to claim 6, characterized in that, The retractable helmet includes four identical locking structures, which are evenly distributed inside the retractable helmet.

8. A retractable helmet according to claim 6, characterized in that, The bottom shell includes a first and a second shell in the shape of an annulus. The first shell is located between the top shell and the second shell. The outer diameter of the top shell is smaller than the inner diameter of the first shell, and the outer diameter of the first shell is smaller than the inner diameter of the second shell. The buckle is fixedly connected to the top shell, and one end of the sliding strip is fixedly connected to the second shell. When the buckle releases the sliding strip, the sliding strip can slide back and forth along the buckle to drive the top shell to retract into the first shell, and the first shell to retract into the second shell; or to drive the top shell to extend out of the first shell, and the first shell to extend out of the second shell.

9. A retractable helmet according to claim 8, characterized in that, The locking structure includes a first locking part and a second locking part with identical structures. The first locking part is disposed between the top shell and the first shell, and its arc-shaped body is rotatably connected to the top shell. The first shell has a first locking position that cooperates with the outward flange of the first locking part. The second locking part is disposed between the first shell and the second shell, and its arc-shaped body is rotatably connected to the first shell. The second shell has a second locking position that cooperates with the outward flange of the second locking part. When the top shell retracts into the first shell and the first shell retracts into the second shell, the outward flange of the first locking part disengages from the first locking position, and simultaneously, the outward flange of the second locking part disengages from the second locking position. When the top shell extends out of the first shell and the first shell extends out of the second shell, the outward flange of the first locking part engages with the first locking position, and simultaneously, the outward flange of the second locking part engages with the second locking position.

10. A retractable helmet according to claim 1, characterized in that, The top shell and / or the bottom shell are provided with a sliding groove, and the sliding bar is disposed in the sliding groove and can slide back and forth along the sliding groove.

Images