Rapidly detachable staying type bolt system

Abstract

The present invention relates to a quickly detachable resident bolt system for connecting a sandwich structure, comprising: a bushing mounted to a structural hole of a sandwich; the supporting plate is mounted in the bushing and is provided with a spring mounting groove; the clamping spring is mounted in the spring mounting groove; a rod part of the bolt comprises a polished rod section and a threaded section, and an annular groove is formed in the peripheral surface of the tail end of the threaded section; in the installation state, the bolt penetrates through the supporting plate, the clamping spring is in the compressed state and tightly attached to the polished rod section of the bolt, and the threaded section of the bolt penetrates through the lining and is in threaded connection with the interlayer. And in the dismounting state, the bolt is not in threaded connection with the interlayer, and the clamping spring is clamped into the annular groove of the bolt, so that the resident anti-falling function of the bolt is achieved. The annular groove is adopted to replace traditional axial grooving, and the situation that the overall strength of the bolt is weakened is avoided.

Description

Technical Field

[0001] This invention relates to a quick-release anchor bolt system. Background Technology

[0002] Aircraft structures contain numerous covers that require frequent disassembly, and their fasteners are installed using a strict "matching" method, with each fastener being unique. Addressing the structural shortcomings of traditional stationary bolts, this project proposes a novel quick-release stationary bolt design.

[0003] Traditional retained bolts achieve retaining by creating three axial grooves at the threaded connection point on the bolt shank. This structure has significant drawbacks:

[0004] (1) The groove structure reduces the tensile strength of the bolt by about 30%, which fails to meet the mechanical performance requirements of high-strength fasteners.

[0005] (2) The three groove design makes the stress concentration factor reach 2.5, which makes it easy to generate fatigue cracks at the root of the thread.

[0006] (3) The fit between the retaining ring and the groove is difficult to control, and there is a risk of loosening.

[0007] The information disclosed in the background section of this invention is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a quick-release anchor bolt system that uses an annular groove instead of the traditional axial slot, thus avoiding weakening the overall strength of the bolt.

[0009] To address the aforementioned problems, this invention provides a quick-release, stationary bolt system for connecting a sandwich structure, comprising: a bushing with a structural hole in the sandwich structure; a support plate installed within the bushing and having a spring mounting groove; a clamping spring installed within the spring mounting groove; and a bolt, the bolt having a smooth section and a threaded section, the outer circumferential surface of the threaded section having an annular groove; wherein, in the installed state, the bolt passes through the support plate, the clamping spring is compressed and closely abuts the smooth section of the bolt, and the threaded section of the bolt passes through the bushing and is threadedly connected to the sandwich structure; in the disassembled state, the bolt is not threadedly connected to the sandwich structure, and the clamping spring engages with the annular groove of the bolt to achieve a stationary, anti-loosening function for the bolt.

[0010] Preferably, the smooth section and the threaded section adopt a smooth transition chamfer structure to reduce stress concentration and thus improve fatigue life.

[0011] Preferably, the bolt head has a hexagonal head, a dodecagonal head, or an internal hexagonal head.

[0012] Preferably, the threaded section has a double-ended thread for quick disassembly and installation.

[0013] Preferably, the clamping spring includes: a spring body in the shape of a ring; and at least two stop portions extending inward from the inner surface of the spring body and evenly distributed along the circumferential direction; the inner end of the stop portion is provided with a U-shaped or V-shaped clamping surface.

[0014] Preferably, the annular groove has a limiting surface extending radially on the side away from the bolt head to prevent the stop from disengaging from the annular groove; the annular groove has a guiding surface on the side near the bolt head, which gradually approaches the bolt head as it extends radially outward, so that the bolt can squeeze the stop when tightened, thereby pushing the stop out of the annular groove, so that the stop does not obstruct the bolt from moving towards the interlayer.

[0015] Preferably, the diameter of the circular profile formed by the inner ends of at least two stop portions is smaller than the diameter of the smooth section of the bolt, so as to ensure that the bolt can pass smoothly during disassembly and be securely locked at the annular groove.

[0016] Preferably, the spring mounting groove of the tray includes a through groove and a receiving groove located around the through groove; there is a baffle between the through groove and the receiving groove, and the baffle is circumferentially provided with a connecting groove matching the number of the stop parts, the spring body is installed in the receiving groove, and the stop parts extend from the receiving groove through the connecting groove into the through groove to clamp the bolt.

[0017] Preferably, the bushing comprises, integrally formed: a first bushing portion having a passage cavity for bolt passage; and a second bushing portion having a receiving cavity for receiving a support plate and a clamping spring; wherein the outer diameter of the second bushing portion is larger than the outer diameter of the first bushing portion, and the diameter of the receiving cavity is larger than the diameter of the passage cavity, forming a stepped structure.

[0018] Preferably, the receiving groove is located inside the receiving cavity and its opening faces the passage cavity.

[0019] Preferably, the bushing is made of 301 / 302 stainless steel or pure titanium.

[0020] The embodiment of the present invention uses an annular concave groove instead of the traditional axial groove, which has the following advantages:

[0021] (1) It avoids the serious weakening of the bolt shank section by the traditional axial groove, greatly reduces the loss of tensile strength, and effectively meets the stringent requirements of high-strength fasteners for mechanical properties.

[0022] (2) The annular groove replaces the axial groove, which significantly reduces the stress concentration factor and greatly extends the service life and reliability of the bolt under alternating loads.

[0023] (3) The annular groove replaces the axial groove, which effectively solves the problem of difficult control of the fit clearance caused by the machining and assembly tolerance of the axial groove structure, and greatly reduces the possibility of fasteners loosening under vibration or impact conditions.

[0024] The methods and apparatus of the present invention have other features and advantages that will be apparent from or will be set forth in detail in the accompanying drawings and subsequent embodiments incorporated herein, which together serve to explain the particular principles of the invention. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of the quick-release anchor bolt system according to an embodiment of the present invention in the installed state;

[0026] Figure 2 This is a cross-sectional view of the quick-release anchor bolt system according to an embodiment of the present invention in the disassembled state;

[0027] Figure 3 This is a schematic diagram of the bolt structure;

[0028] Figure 4 Schematic diagram of the clamping spring structure Figure 1 ;

[0029] Figure 5 Schematic diagram of the clamping spring structure Figure 2 ;

[0030] Figure 6 This is a structural diagram of the pallet;

[0031] Figure 7 This is a sectional view of the pallet;

[0032] Figure 8 This is a structural diagram of the pallet from another perspective;

[0033] Figure 9 This is a schematic diagram showing the fit between the support plate and the clamping spring;

[0034] Figure 10 This is a schematic diagram of the bushing structure;

[0035] Figure 11This is a sectional view of the bushing.

[0036] Explanation of reference numerals in the attached figures:

[0037] 100. Bushing; 110. First part of bushing; 111. Through cavity; 120. Second part of bushing; 121. Receiving cavity; 122. Limiting part;

[0038] 200, support plate; 210, spring mounting slot; 211, through slot; 212, receiving slot; 213, baffle; 214, connecting slot;

[0039] 300. Clamping spring; 310. Spring body; 320. Stopping part;

[0040] 400. Bolt; 410. Rod; 411. Smooth rod section; 412. Threaded section; 413. Annular groove; 414. Guide surface; 415. Limiting surface; 420. Head;

[0041] 500, interlayer; 501, structural hole.

[0042] It should be understood that the accompanying drawings are not necessarily drawn to scale, but rather present simplified representations of various features to illustrate the basic principles of the invention. Specific design features disclosed in this invention (including, for example, specific dimensions, orientations, positions, and shapes) will be determined in part by the specific environment in which they are intended for application and use.

[0043] Throughout these figures, the same reference numerals denote the same or equivalent parts of the invention. Detailed Implementation

[0044] Reference will now be made in detail to various embodiments of the invention, examples of which are presented in the accompanying drawings and described below. Although the invention will be described in conjunction with exemplary embodiments, it should be understood that this specification is not intended to limit the invention to these exemplary embodiments. Rather, the invention is intended to cover not only these exemplary embodiments, but also various alternatives, modifications, equivalents, and other embodiments that may be included within the spirit of the invention and the scope defined by the appended claims.

[0045] The following is combined Figures 1 to 11 A quick-release anchor bolt system according to an embodiment of the present invention will be described.

[0046] like Figures 1 to 3 As shown, the quick-release stationary bolt system of the present invention, used to connect the sandwich structure 500, includes: bushing 100, support plate 200, clamping spring 300 and bolt 400.

[0047] Bushing 100 is installed into structural hole 501 of interlayer 500.

[0048] The tray 200 is installed inside the bushing 100 and has a spring mounting groove 210.

[0049] The clamping spring 300 is installed in the spring mounting slot 210.

[0050] The shank 410 of the bolt 400 includes a smooth shank section 411 and a threaded section 412. The outer circumferential surface of the end of the threaded section 412 is provided with an annular groove 413 as a retention and limiting structure.

[0051] Among them, such as Figure 1 As shown, in the installed state, the bolt 400 passes through the support plate 200, the clamping spring 300 is in a compressed state and is in close contact with the smooth rod section 411 of the bolt 400, and the threaded section 412 of the bolt 400 passes through the bushing 100 and is threadedly connected to the interlayer 500.

[0052] like Figure 2 As shown, in the disassembled state, the bolt 400 is not threadedly connected to the interlayer 500, and the clamping spring 300 is engaged in the annular groove 413 of the bolt 400 to achieve the retention and anti-loosening function of the bolt 400.

[0053] The embodiment of the present invention uses an annular groove 413 instead of the traditional axial slot, which has the following advantages:

[0054] (1) It avoids the serious weakening of the bolt shank section by the traditional axial groove, greatly reduces the loss of tensile strength, and effectively meets the stringent requirements of high-strength fasteners for mechanical properties.

[0055] (2) The annular groove 413 replaces the axial groove, which significantly reduces the stress concentration factor and greatly extends the service life and reliability of the bolt under alternating loads.

[0056] (3) The annular groove 413 replaces the axial groove, which effectively solves the problem of difficult control of the fit clearance caused by the machining and assembly tolerance of the axial groove structure, and greatly reduces the possibility of fasteners loosening under vibration or impact conditions.

[0057] Furthermore, a nut is provided on the interlayer 500, and the threaded section 412 of the bolt 400 is threadedly connected to the nut to achieve a threaded connection with the interlayer 500.

[0058] In an exemplary embodiment, the bottom of the annular groove 413 employs a rounded transition structure (e.g., a radius or rounded corner). This rounded transition structure effectively avoids the formation of sharp angles or stress concentration points in the bottom region of the groove. By optimizing the radius of this arc (e.g., selected based on the material strength, expected load, and fatigue life requirements of the bolt 400), the localized stress peaks generated in the bottom region of the annular groove 413 during bolt 400 use (especially under cyclic loads or vibration) are significantly reduced. This stress reduction directly contributes to improving the overall fatigue resistance of the bolt 400, thereby extending its fatigue life.

[0059] The preload of the clamping spring 300 is calculated to ensure that it can reliably lock the bolt 400 without causing excessive wear to the annular groove 413.

[0060] Specifically, calculating the preload of the clamping spring 300 requires comprehensive consideration of several key factors, including but not limited to: the material properties of the clamping spring 300 (such as elastic modulus and yield strength), structural dimensions (such as wire diameter, number of coils, and free length), the material hardness and surface treatment of the bolt 400, the geometry and surface finish of the annular groove 413, and the expected maximum working load and vibration environment. Calculating the preload of the clamping spring 300 ensures that it provides sufficient radial clamping force to reliably lock the bolt 400 in axial displacement (i.e., prevent accidental bolt loosening). Simultaneously, this preload is strictly controlled within a safe range to avoid excessive wear on the contact surface of the annular groove 413 (e.g., exceeding the material's allowable contact stress or causing fretting wear). This balanced design ensures both the reliability of the connection and maximizes the protection of the structural integrity of the annular groove 413, preventing clamping failure or bolt damage due to long-term wear.

[0061] In an exemplary embodiment, the smooth section 411 and the threaded section 412 of the rod 410 adopt a smooth transition chamfer structure to reduce stress concentration and thus improve fatigue life. For example, the smooth transition chamfer structure can be selected from forms such as rounded corner transition, bevel transition, or optimized curve transition.

[0062] A smooth transition chamfer structure can eliminate or significantly reduce stress concentration caused by abrupt geometric changes at the connection between the smooth section 411 and the threaded section 412 (especially at the root of the thread). By providing this smooth geometric transition, the stress peak in this local area under load (especially cyclic or alternating loads) can be effectively dispersed and reduced. This reduction in stress concentration directly helps to delay the initiation and propagation of fatigue cracks in this critical connection area, thereby significantly improving the fatigue resistance and service life of the shank 410 and even the entire connection structure under long-term service conditions. Furthermore, this smooth transition chamfer structure can be achieved through processes such as turning, grinding, or cold forming, and its geometric parameters (such as chamfer radius, chamfer angle, or transition curve shape) can be optimized according to specific application requirements and material properties.

[0063] In an exemplary embodiment, the head 420 of the bolt 400 is provided with a wrench structure for transmitting torque. This wrench structure can be configured in various forms, including but not limited to: external wrench structures, such as hex heads or dodecagon heads (e.g., double hex heads or Torx heads); or internal wrench structures, such as Allen sockets, Torx sockets, Phillips / Cross Recesses, Slotted slots, etc. This wrench structure provides an effective engagement interface with corresponding drive tools (such as wrenches, sockets, screwdrivers, etc.) to achieve reliable tightening or loosening of the bolt 400. The specific wrench structure can be adapted to the application scenario based on requirements such as torque transmission capability, space constraints, anti-slip performance, and aesthetics.

[0064] In an exemplary embodiment, threaded segment 412 employs a double-start thread. Choosing a double-start thread allows for a larger lead (i.e., the distance the thread travels along its axis during one revolution) compared to a single-start thread. Due to the increased lead, threaded segment 412 and its mating parts can reach the predetermined axially disengaged position (disassembly) or axially engaged locking position (installation) more quickly when the same rotational drive is applied (whether using a hand tool such as a wrench or screwdriver, or an automatic tool). Therefore, this design significantly improves the efficiency of connection / disconnection operations, reduces operation time, and is ideal for applications requiring frequent assembly, disassembly, maintenance, or adjustment.

[0065] In an exemplary implementation, such as Figure 4 and Figure 5 As shown, the clamping spring 300 includes: a spring body 310 and at least two stop portions 320.

[0066] The spring body 310 is annular. This annular structure can be a continuous closed loop (not shown in the figure) to provide a uniform circumferential elastic force, or it can be a C-shaped loop with an opening (see figure for details). Figure 4 and Figure 5 This facilitates assembly. The main function of the spring body 310 is to provide an elastic support base. Preferably, the spring body 310 has an opening in the form of a C-shaped ring, which can deform radially.

[0067] The stop portion 320 extends inward from the inner surface of the spring body 310 and is evenly distributed along the circumferential direction to clamp the bolts 400. The inner end of the stop portion 320 is provided with a U-shaped clamping surface (see mating details). Figure 5 ) or V-shaped clamping surface (see details below) Figure 4 This circumferentially evenly distributed arrangement applies a balanced and symmetrical radial clamping force to the bolt circumference. This force balance is crucial to preventing the bolt 400 from misaligning, vibrating, or experiencing abnormal wear on one side within the clamping holes, thereby improving connection stability and service life. The number of stops 320 can be adjusted according to the required clamping force and stability, for example, to two, three, four, or more.

[0068] U-shaped or V-shaped clamping surfaces provide stable radial clamping force. The U-shaped clamping surface, with its concave arc profile, offers a larger contact area and better containment, which helps distribute stress and improve stability. The V-shaped clamping surface, with its sharp or slightly rounded angle design, can more accurately position and generate higher local contact pressure, thus achieving a firm clamping grip.

[0069] The specific shape of the inner end of the stop 320 is not limited to the aforementioned U-shaped or V-shaped clamping surface; it can adopt any other suitable form known in the prior art that can achieve effective clamping function. For example, the end face configuration can also be: a flat type (for simple clamping), a surface with teeth or knurling (to increase friction and anti-slip capability), a spherical type (to provide point contact to adapt to different angles), or other irregular contours (such as wavy, multi-segment arc surfaces, etc.).

[0070] In an exemplary embodiment, the clamping spring 300 is made of a metallic material with excellent elasticity and high strength, preferably a highly elastic stainless steel, such as 17-7PH precipitation-hardening stainless steel or 302 austenitic stainless steel. The clamping spring 300 is configured to provide a continuous radial clamping force to the bolt 400. The clamping spring 300, made of the aforementioned highly elastic stainless steel, significantly improves its reliability and durability under long-term service conditions, effectively reducing maintenance needs or component failures caused by material performance degradation (such as relaxation, fracture, and corrosion).

[0071] In an exemplary implementation, such asFigure 1 and Figure 2 As shown, the annular groove 413 has a limiting surface 415 extending in the radial direction on the side of the head 420 away from the bolt 400 to prevent the stop 320 from disengaging from the annular groove 413.

[0072] The annular groove 413 has a guide surface 414 on the side near the head 420 of the bolt 400. The guide surface 414 gradually approaches the head 420 of the bolt 400 as it extends radially outward, so that the bolt 400 can squeeze the stop 320 when tightening, thereby pushing the stop 320 out of the annular groove 413. This ensures that the stop 320 does not obstruct the bolt from moving towards the interlayer 500, that is, it does not affect the tightening of the bolt 400.

[0073] When the bolt 400 moves in the tightening direction (near the interlayer 500), the guide surface 414 presses against the stop part 320 and pushes it radially out of the annular groove 413, thereby releasing the lock and allowing the bolt 400 to complete the tightening smoothly.

[0074] The guide surface 414 is a cone or an inclined slope. Alternatively, the guide surface 414 can be an inclined plane or an inclined curved surface.

[0075] In other embodiments, the stop portion 320 may also be provided with a guide surface, which gradually approaches the head 420 of the bolt 400 as it extends radially outward, serving the same function as the guide surface 414 described above. The guide surface of the stop portion 320 and the guide surface 414 of the bolt 400 may coexist, or only one of them may be provided.

[0076] In an exemplary embodiment, the diameter of the circular profile formed by the inner ends of at least two stop portions 320 is smaller than the diameter of the smooth rod section 411 of the bolt 400, to ensure that the bolt 400 can pass smoothly during disassembly and be securely locked at the annular groove 413.

[0077] The inner ends of at least two stop portions 320 together define a circular profile. The smooth rod segment 411, with its larger diameter, can overcome the elastic constraint of the stop portion 320, forcing the clamping spring 300 to elastically deform, thereby allowing the smooth rod segment 411 to pass axially through the area defined by the inner ends of the stop portions 320 without interference. Subsequently, when the bolt 400 moves to a position where its annular groove 413 aligns with the stop portion 320, the inner end of the stop portion 320 is radially inserted into the annular groove 413, thereby forming a reliable mechanical lock (or limit), effectively preventing the bolt 400 from continuing to move axially (especially in the retraction direction), achieving a stable positioning of the bolt 400 in a specific position.

[0078] In an exemplary implementation, such asFigures 6 to 9 As shown, the spring mounting groove 210 of the tray 200 includes a through groove 211 and a receiving groove 212 located on the periphery of the through groove 211.

[0079] A baffle 213 exists between the through groove 211 and the receiving groove 212. The baffle 213 is circumferentially provided with a connecting groove 214 matching the number of stop parts 320. The spring body 310 is installed in the receiving groove 212. The stop part 320 extends from the receiving groove 212 through the connecting groove 214 into the through groove 211 to clamp the bolt 400.

[0080] The spring body 310 is blocked by the baffle 213 in the receiving groove 212 and cannot enter the passage groove 211. Thus, during disassembly, the clamping spring 300 will not fail under any circumstances, and the clamping spring 300 will not be pulled away from the bushing 100 by the bolt 400 under any circumstances. The stop part 320 will inevitably be locked into the annular groove 413 to prevent it from falling off.

[0081] If the clamping spring 300 is not equipped with the stop part 320, but is instead a conventional ring spring, then during disassembly, the clamping spring 300 will deform and, under certain circumstances (e.g., with increased force), can completely enter the through groove 211 and be pulled out along with the bolt 400. Therefore, the reliability of this solution is generally low. In this invention, the spring body 310 of the clamping spring 300 is restricted within the receiving groove 212 by the baffle 213 and cannot enter the through groove 211, thus preventing the clamping spring 300 from being pulled out along with the bolt 400.

[0082] In an exemplary embodiment, the pallet 200 is made of a high-strength material, such as, but not limited to, high-strength aluminum alloy or alloy steel. The use of high-strength aluminum alloy can simultaneously meet the requirements of lightweighting, while alloy steel can provide extremely high rigidity and strength.

[0083] In an exemplary embodiment, the width of the receiving groove 212 in the radial direction is greater than the width of the spring body 310 in the radial direction, so as to provide space for the elastic deformation of the spring body 310.

[0084] In an exemplary implementation, such as Figure 10 and Figure 11 As shown, bushing 100 includes a first bushing portion 110 and a second bushing portion 120 formed integrally.

[0085] The first portion 110 of the bushing has a passage cavity 111 for the bolt 400 to pass through. Specifically, the passage cavity 111 is configured to allow the bolt 400 to pass through without interference, and the spaces between the passage cavities 111 are adapted to the diameter of the shank 410 of the bolt 400, typically slightly larger than the diameter of the shank 410 of the bolt 400, to provide an assembly clearance for the bolt 400.

[0086] The second part 120 of the bushing has a receiving cavity 121 to receive the tray 200 and the clamping spring 300.

[0087] The outer diameter of the second part 120 of the bushing is larger than that of the first part 110 of the bushing. This increase in outer diameter not only increases the space of the receiving cavity 121, but more importantly, it enhances the structural rigidity and strength of the second part 120 of the bushing, enabling it to better withstand loads from the support plate 200, the clamping spring 300, and the working conditions (such as vibration, impact, or clamping force).

[0088] The diameter of the receiving cavity 121 is larger than the diameter of the cavity 111, forming a stepped structure. This stepped structure provides a reliable axial support surface for the support plate 200 and the clamping spring 300 housed within the receiving cavity 121. In both the assembled and operating states, this stepped structure effectively prevents the support plate 200 and the clamping spring 300 from moving towards the first portion 110 of the bushing (e.g., ...). Figure 10 Unexpected axial movement occurs (as shown above), ensuring they remain stably in their intended positions.

[0089] In addition, during assembly, the stepped structure serves as a clear reference surface for the placement of the support plate 200 and the clamping spring 300, simplifying the assembly process and ensuring the consistency and accuracy of the component's position within the bushing.

[0090] The bushing 100 can be pressed into the structural hole 501 using a cold extrusion process to form an interference fit, ensuring that the bushing 100, the support plate 200, and the clamping spring 300 will not loosen. This process is carried out at or near room temperature. By applying precisely controlled axial pressure, the outer wall of the bushing first part 110 of the bushing 100 undergoes controllable plastic deformation, thereby forming a reliable interference fit between the bushing 100 and the structural hole 501.

[0091] The bushing 100 is typically made of 301 / 302 stainless steel or pure titanium, offering advantages such as cold deformation and excellent plasticity. The core reason for choosing these materials is their exceptional cold-working deformation capability and high plasticity. This outstanding cold-working characteristic allows the bushing 100 to effectively avoid cracking or excessive thinning even during complex plastic forming processes such as stamping, spinning, deep drawing, or bending at room temperature or lower temperatures, significantly improving manufacturing yield and reducing processing costs. Simultaneously, its superior plasticity ensures that during final assembly or service, when subjected to localized impact loads, stresses from interference fits, or requiring minor shape adjustments to accommodate mating parts, the bushing 100 can absorb energy or adapt to tolerances through its own small, controllable plastic deformation, rather than undergoing brittle fracture. This greatly enhances the overall reliability and service life of the component. This material characteristic is crucial for bushing applications requiring precise fits and potentially subject to dynamic loads.

[0092] like Figure 1 and Figure 11 As shown, an inwardly extending limiting portion 122 is provided on the side of the second part 120 of the bushing away from the first part 110 of the bushing, forming an axial blocking structure. When the support plate 200 and the clamping spring 300 are assembled in the receiving cavity 121, the limiting portion 122 is located on the side of the support plate 200 and / or the clamping spring 300 away from the first part 110 of the bushing, and forms an interference or abutment relationship with it in the axial direction. Thus, the limiting portion 122 can prevent the support plate 200 and the clamping spring 300 from moving or disengaging in the direction away from the first part 110 of the bushing, thereby firmly limiting both within the predetermined space of the receiving cavity 121, ensuring the structural integrity and functional stability of the assembly.

[0093] The aforementioned limiting part 122 can take various forms, such as an annular boss extending inward from the end face of the second part 120 of the bushing. Alternatively, it can be a plurality of inwardly protruding tongues, claws, or protrusions distributed circumferentially; or an inwardly tapering structure formed by means of curling, riveting, welding, etc.

[0094] In an exemplary embodiment, the receiving groove 212 is located inside the receiving cavity 121 and its opening faces the passage cavity 111. With the cooperation of the aforementioned stepped structure, the clamping spring 300 can be prevented from accidentally dislodging from the receiving groove 212.

[0095] The operation of the quick-release anchor bolt system according to the embodiments of the present invention will be described below with reference to the accompanying drawings.

[0096] Installation state: Bolt 400 passes through support plate 200, clamping spring 300 is in a compressed state and closely abuts the smooth rod section 411 of bolt 400, then the threaded section 412 of bolt 400 continues to pass through the inner hole of bushing 100 fixed on structural hole 501, and then is connected to interlayer 500 by nut.

[0097] After bolt 400 is screwed into nut, clamping spring 300 acts only on the smooth section 411 of bolt 400. Its position and structural design ensure that it does not extend to cover or interfere with the threaded engagement area of ​​threaded section 412. This spatial isolation design effectively ensures normal and sufficient torque transmission between bolt 400 and nut, ensuring the mechanical properties and reliability of the connection point. In other words, it ensures normal tightening function.

[0098] Disassembly state: After the bolt 400 is unscrewed from the nut, it continues to retract into the bushing 100, and then passes through the clamping spring 300 to the bare section 411. When the annular groove 413 of the bolt 400 reaches the position of the clamping spring 300, the stop part 320 of the clamping spring 300 springs into the annular groove 413, forming a mechanical limit to prevent the bolt 400 from completely falling off.

[0099] Through the mechanical limiting mechanism established during the disassembly process described above, bolt 400 is reliably held on the support plate 200 in a partially retracted, stationary state. This design offers significant practical advantages:

[0100] (1) Prevention of loss: Bolt 400 will not fall off or be lost after disassembly, especially in high-altitude, confined spaces or scenarios requiring frequent maintenance.

[0101] (2) Preventing incorrect assembly: Bolt 400 is always associated with the corresponding support plate 200, avoiding the risk of using bolts of other specifications or positions during subsequent reassembly.

[0102] (3) Improve assembly efficiency: When reinstallation is required, the operator does not need to find and take new bolts. The operator can directly use the bolts 400 that are stationed on the pallet 200 to operate, which simplifies the assembly process and improves maintenance efficiency.

[0103] (4) Reliability: The mechanical interlocking structure formed by the annular groove 413 and the clamping spring 300 is simple and reliable, and can effectively prevent the bolt 400 from falling off accidentally even in a vibration environment.

[0104] For ease of interpretation and precise definition of the appended claims, the terms “upper,” “lower,” “inner,” “outer,” “above,” “below,” “above,” “below,” “upward,” “downward,” “front,” “back,” “behind,” “inner side,” “outer side,” “inward,” “outer,” “internal,” “external,” “inner,” “external,” “forward,” and “backward” are used to describe the features of the exemplary embodiments with reference to the positions of these features shown in the accompanying drawings.

[0105] The foregoing description of specific exemplary embodiments of the invention is for illustrative and descriptive purposes. It is not intended to be exhaustive, nor to limit the invention to the precise forms disclosed; clearly, many changes and variations are possible in accordance with the foregoing teachings. The exemplary embodiments were chosen and described to explain the specific principles of the invention and its practical application, thereby enabling others skilled in the art to implement and utilize various exemplary embodiments of the invention, as well as their different alternatives and modifications. The scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A quick-release anchor bolt system for connecting a sandwich structure (500), characterized in that, include: Bushing (100), which is installed into the structural hole (501) of the interlayer (500); A tray (200) is installed inside the bushing (100) and has a spring mounting groove (210). A clamping spring (300) is mounted in the spring mounting slot (210); and The bolt (400) has a shank (410) including a smooth shank section (411) and a threaded section (412), wherein an annular groove (413) is provided on the outer peripheral surface of the end of the threaded section (412). In the installed state, the bolt (400) passes through the support plate (200), the clamping spring (300) is in a compressed state and is in close contact with the bare rod section (411) of the bolt (400), and the threaded section (412) of the bolt (400) passes through the bushing (100) and is threadedly connected to the interlayer (500). In the disassembled state, the bolt (400) is not threaded to the interlayer (500), and the clamping spring (300) is engaged in the annular groove (413) of the bolt (400) to achieve the function of retaining and preventing the bolt (400) from falling off.

2. The quick-release anchor bolt system according to claim 1, characterized in that, The smooth rod section (411) and the threaded section (412) adopt a smooth transition chamfer structure to reduce stress concentration and thus improve fatigue life.

3. The quick-release anchor bolt system according to claim 1, characterized in that, The bolt (400) head (420) has a hexagonal head, dodecagonal head, or internal hexagonal head.

4. The quick-release anchor bolt system according to claim 1, characterized in that, The threaded section (412) uses a double-ended thread for quick disassembly and installation.

5. The quick-release anchor bolt system according to claim 1, characterized in that, The clamping spring (300) includes: The spring body (310) is ring-shaped; and At least two stop portions (320) extend inward from the inner surface of the spring body (310) and are evenly distributed in the circumferential direction; The inner end of the stop part (320) is provided with a U-shaped or V-shaped clamping surface.

6. The quick-release anchor bolt system according to claim 5, characterized in that, The annular groove (413) has a limiting surface (415) extending radially on the side away from the head (420) of the bolt (400) to prevent the stop (320) from disengaging from the annular groove (413). The annular groove (413) has a guide surface (414) on the side near the head (420) of the bolt (400). The guide surface (414) gradually approaches the head (420) of the bolt (400) as it extends radially outward, so that the bolt (400) can squeeze the stop (320) when tightened, thereby pushing the stop (320) out of the annular groove (413) so that the stop (320) does not hinder the bolt (400) from moving toward the interlayer (500).

7. The quick-release anchor bolt system according to claim 5, characterized in that, The spring body (310) has an opening that allows it to deform radially. The diameter of the circular profile formed by the inner ends of at least two stop portions (320) is smaller than the diameter of the smooth rod section (411) of the bolt (400) to ensure that the bolt (400) can pass smoothly during disassembly and be securely locked at the annular groove (413).

8. The quick-release anchor bolt system according to claim 5, characterized in that, The spring mounting groove (210) of the tray (200) includes a through groove (211) and a receiving groove (212) located around the through groove (211). There is a baffle (213) between the through groove (211) and the receiving groove (212). The baffle (213) is circumferentially provided with a connecting groove (214) matching the number of the stop (320). The spring body (310) is installed in the receiving groove (212). The stop (320) extends from the receiving groove (212) through the connecting groove (214) into the through groove (211) to clamp the bolt (400).

9. The quick-release anchor bolt system according to claim 8, characterized in that, The bushing (100) comprises integrally formed of: The first part of the bushing (110) has a passage cavity (111) for the bolt (400) to pass through; The second part of the bushing (120) has a receiving cavity (121) to receive the tray (200) and the clamping spring (300). The outer diameter of the second part of the bushing (100) is larger than the outer diameter of the first part of the bushing (100), and the diameter of the receiving cavity (121) is larger than the diameter of the through cavity (111) to form a stepped structure.

10. The quick-release anchor bolt system according to claim 9, characterized in that, The receiving groove (212) is located inside the receiving cavity (121) and its opening faces the passage cavity (111).

11. The quick-release anchor bolt system according to claim 1, characterized in that, The bushing (100) is made of 301 / 302 stainless steel or pure titanium.

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