Automobile safety belt retractor with pre-tensioning
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG WANLI SAFETY EQUIP MFG
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-26
Smart Images
Figure CN122275802A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of automotive seat belt technology, specifically to an automotive seat belt retraction device with a pretensioning structure. Background Technology
[0002] Seat belts are a core component of vehicle occupant restraint systems. In emergency situations such as collisions and sudden deceleration, they effectively limit the forward displacement of occupants, preventing secondary collisions with rigid structures inside the vehicle such as the steering wheel, dashboard, and windshield. They are a crucial protective component for reducing the risk of injury or death in traffic accidents. The seat belt retractor, as the core functional unit of the seat belt assembly, plays a vital role in the free retraction and extension of the webbing and in locking and limiting its position in emergency situations. Its locking response speed, reliability, and structural stability directly determine the overall protective performance of the seat belt. Among these, purely mechanically triggered retractors, due to their independence from the vehicle's electronic control system and external power source, reusability, and strong environmental adaptability, have become an important research and application direction in the field of automotive passive safety.
[0003] Existing purely mechanical pretensioning seatbelt retractors mostly rely on centrifugal triggering to achieve locking protection. In a vehicle collision, the webbing is rapidly pulled out, causing the reel to rotate at high speed, which in turn triggers the centrifugal locking mechanism. The reel is locked by the engagement of a pawl and a ratchet, thus completing the webbing pretensioning and occupant restraint. However, in practical applications, this type of structure generally only uses a single locking mechanism, lacking redundant protection design. It relies solely on a single locking mechanism to handle all occupant restraint functions in a collision, exhibiting a core flaw of single-point failure. If this locking mechanism malfunctions, the retractor will completely lose its locking protection capability, making it difficult to provide effective restraint for occupants in a collision, posing a serious safety hazard.
[0004] Therefore, there is an urgent need to develop a car seat belt retraction device with a pretensioning structure to solve the above-mentioned problems in the existing technology. Summary of the Invention
[0005] The purpose of this invention is to provide an automotive seatbelt retractor with a pretensioning structure, which has the advantage of dual redundant locking protection and effectively solves the problem that existing pure mechanical pretensioning seatbelt retractors only have a single locking mechanism and no redundant protection design, resulting in a single point of failure risk.
[0006] To achieve the above objectives, the present invention provides the following technical solution: a car seatbelt retraction device with a pretensioning structure, comprising a pretensioning mechanism, a drive shaft, and a reset mechanism. The pretensioning mechanism includes a first pretensioning component, a second pretensioning component, and an adaptive driven component. The first pretensioning component is coaxially fixed to the drive shaft and is a centrifugal locking structure configured to trigger locking upon high-speed rotation of the drive shaft, directly restricting the circumferential rotation of the drive shaft. The second pretensioning component includes a ratchet and a pawl. The ratchet is coaxially fixed to the drive shaft, and the pawl can... The adaptive driven component engages with the ratchet to limit the circumferential rotation of the drive shaft; the adaptive driven component is driven by the drive shaft, and the power output end of the adaptive driven component is driven by the drive end of the ratchet. The adaptive driven component is a centrifugal drive structure, configured to drive the ratchet to engage with the ratchet as the drive shaft rotates at high speed; the first pretensioning component and the second pretensioning component form two sets of independent and synchronously triggered locking actuators, constituting a double redundant locking protection structure; the reset mechanism is driven by the drive shaft and is used to drive the drive shaft to complete the rewinding and reset of the seat belt.
[0007] Preferably, the pre-tightening mechanism further includes an installation chamber, one side of which is open; the first pre-tightening component is installed inside the installation chamber, the second pre-tightening component is installed outside the installation chamber, and the adaptive driven component is installed in the internal cavity of the installation chamber.
[0008] Preferably, the first pre-tightening assembly includes an internal gear ring, a central turntable, two sets of centrifugal tooth blocks, and two sets of tooth block tension springs; the internal gear ring is fixedly installed on the inner side wall of the installation chamber, and the inner wall of the internal gear ring is provided with limiting internal teeth along the circumferential direction; the central turntable is coaxially disposed on the inner side of the internal gear ring, and the central turntable is coaxially fixed with the drive shaft, and two radial grooves are symmetrically provided on both sides of the central turntable, and the two sets of centrifugal tooth blocks are slidably installed in the two radial grooves respectively; one end of the tooth block tension spring is fixedly connected to the bottom of the radial groove, and the other end of the tooth block tension spring is fixedly connected to the inner end of the centrifugal tooth block, and the outer end of the centrifugal tooth block can mesh with the limiting internal teeth.
[0009] The preferred structure of the first preload assembly enables a purely mechanical centrifugal locking trigger that rotates at high speed with the drive shaft. It has the advantages of rapid locking response, balanced locking force, no dependence on electrical control, and reusable triggering.
[0010] Preferably, the second preload assembly further includes a connecting shaft and a torsion spring; the pawl is disposed on one side of the ratchet; the connecting shaft passes through the mounting hole of the pawl, and one end of the connecting shaft is rotatably connected to the outer wall of the mounting chamber; the torsion spring is sleeved on the connecting shaft, one end of the torsion spring is fixedly connected to the pawl, and the other end of the torsion spring is fixedly connected to the connecting shaft, and the torsion spring is used to keep the pawl separated from the ratchet in a non-powered state; the other end of the connecting shaft passes through the side wall of the mounting chamber and is coaxially fixedly connected to the adaptive driven assembly; a first protective cover is provided on the outside of the ratchet, and the first protective cover is detachably connected to the mounting chamber.
[0011] The preferred structure of the second pretensioning component achieves redundant locking protection synchronized with the first pretensioning component. The torsion spring ensures that the pawl and ratchet remain separated in the absence of power, avoiding interference with the normal retraction and extension of the seat belt. It has the advantages of reliable locking action, no impact on normal use, and strong protective redundancy. The matching first protective cover can form a closed protection for the second pretensioning component, preventing foreign objects from entering and causing the mechanism to jam.
[0012] Preferably, the adaptive driven assembly includes a driven drum, a drive disk, multiple sets of centrifugal shoe blocks, and multiple sets of shoe block tension springs; the driven drum is a cylindrical structure with one open end, and the outer center of the closed end of the driven drum is fixedly connected to a connecting shaft; the drive disk is rotatably mounted in the inner cavity of the driven drum, and multiple radial guide grooves are formed along the circumferential direction on the outer wall of the drive disk, and the multiple sets of centrifugal shoe blocks are slidably mounted in the multiple radial guide grooves respectively; one end of the shoe block tension spring is fixedly connected to the bottom of the radial guide groove, and the other end of the shoe block tension spring is fixedly connected to the inner end of the centrifugal shoe block, and the outer end of the centrifugal shoe block can form a friction mating surface with the inner wall of the driven drum.
[0013] The optimized structure of the adaptive driven component enables adaptive recognition of the rotation state of the drive shaft. Only when the drive shaft rotates at high speed, the second preload component is triggered and locked by the frictional engagement between the centrifugal shoe and the driven drum. It has the advantages of precise triggering logic, no additional electronic control components, and good synchronization with the triggering of the first preload component.
[0014] Preferably, a driven wheel is coaxially fixed at the center of the side of the drive disc opposite to the closed end of the driven drum; an annular groove is provided on the rod of the transmission shaft, a synchronous belt is sleeved in the annular groove, and the other end of the synchronous belt is sleeved on the driven wheel.
[0015] The optimized structure of the synchronous belt drive ensures that the rotation of the drive shaft and the drive disc are completely synchronized, and has the advantages of precise transmission ratio, smooth transmission without slippage, and strong consistency of locking trigger timing.
[0016] Preferably, the open end of the installation compartment is covered with a sealing plate, and the drive shaft and the drive disc are rotatably connected to the sealing plate via bearings.
[0017] The optimized structure of the sealing plate and bearing effectively reduces the frictional resistance during the rotation of the drive shaft and drive disc, ensuring smooth rotation and coaxiality, and has the advantages of stable rotation, low component wear, and long service life.
[0018] Preferably, the reset mechanism includes a mounting plate, a spring, a locating pin, and a second protective cover; the spring is mounted on the mounting plate, and the locating pin is vertically fixed on the end face of the mounting plate facing the spring; a limit slot is formed in the rod section of the drive shaft passing through the mounting plate, the inner end of the spring is engaged and fixed in the limit slot, and the outer end of the spring is engaged and fixed on the locating pin; the second protective cover is fastened and installed on the outer side of the mounting plate, and the second protective cover covers the mounting area of the spring.
[0019] The optimized structure of the reset mechanism enables precise positioning of the spring, ensuring that the spring can stably drive the drive shaft to complete the rewinding and reset of the seat belt. The second protective cover can limit the axial movement of the spring and form a closed protection for it, which has the advantages of stable reset action, accurate installation and positioning, and good component protection effect.
[0020] Preferably, the device further includes a connecting mechanism and an external support mechanism; the connecting mechanism includes a sealing plate and multiple sets of nut columns, the nut columns passing through the sealing plate, and the mounting chamber, sealing plate, external support mechanism, and reset mechanism being sequentially and detachably connected via the nut columns; the external support mechanism has holes corresponding to the nut columns, and the drive shaft passes through the inner side of the external support mechanism; the external support mechanism is an L-shaped frame structure, with its two vertical side plates respectively fitting against the outer side of the sealing plate and the inner side of the mounting plate, and the inner cavity of the external support mechanism accommodating the safety belt body wound on the drive shaft; one end of the nut column is provided with an external thread, the threaded end of the nut column passing through the through hole of the sealing plate and being threadedly fastened to the threaded hole on the side wall of the mounting chamber; the other end of the nut column sequentially passes through the corresponding hole of the external support mechanism and the corresponding through hole of the mounting plate, and is threadedly locked to the mounting plate by bolts.
[0021] The optimized structure of the connecting mechanism and the external support mechanism enables the sequential locking and fixing of each component. The L-shaped frame structure of the external support mechanism accommodates and protects the seat belt body, while ensuring the assembly stability of the overall structure. It has the advantages of convenient assembly and disassembly, high connection strength, accurate positioning of each component, good overall coaxiality consistency, compact structure, and small installation space occupation.
[0022] Preferably, the device further includes a seat belt body, one end of which is fixedly connected to the rod wall of the drive shaft, the seat belt body is circumferentially wound around the drive shaft, and the other end of which passes through the frame gap of the outer support mechanism.
[0023] The matching structure of the seat belt body enables smooth extraction and retraction with the rotation of the drive shaft, and has the advantages of smooth operation and high matching degree with the pre-tensioning locking mechanism.
[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention, by setting a first pretensioning component and a second pretensioning component coaxially fixed to the drive shaft in the pretensioning mechanism, and simultaneously configuring an adaptive driven component that is driven by the drive shaft and driven by the pawl drive end of the second pretensioning component, enables the first and second pretensioning components to be synchronously triggered to lock as the drive shaft rotates at high speed, forming two independent locking actuators and constructing a dual-redundant locking protection structure. When one locking mechanism malfunctions, the other locking mechanism can still lock and limit the drive shaft, effectively solving the problem that existing pure mechanical pretensioning seat belt retractors only have a single locking mechanism and no redundant protection design, resulting in a single-point failure risk, and significantly improving the protection reliability of the retracting device under collision conditions. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the structure from one perspective of the present invention; Figure 2 This is a schematic diagram of the structure from another perspective of the present invention; Figure 3 This is a schematic diagram of the split structure from one perspective of the present invention; Figure 4 This is a schematic diagram of the split structure from another perspective of the present invention; Figure 5 This is a schematic diagram of the connection structure of the pre-tightening mechanism of the present invention from one perspective; Figure 6 This is a schematic diagram of the connection structure of the pre-tightening mechanism of the present invention from another perspective; Figure 7 This is a schematic cross-sectional view of the first pre-tightening component of the present invention; Figure 8 For the present invention Figure 7 A magnified view of the structure at point A in the middle; Figure 9 This is a schematic cross-sectional view of the adaptive driven component of the present invention.
[0026] In the diagram: 1. Pre-tightening mechanism; 11. Mounting chamber; 12. First protective cover; 13. First pre-tightening assembly; 131. Internal gear ring; 132. Limiting internal gear; 133. Central turntable; 1331. Radial slide groove; 134. Centrifugal gear block; 135. Gear block tension spring; 14. Drive shaft; 141. Limiting slot; 142. Annular belt groove; 143. Synchronous belt; 15. Second pre-tightening assembly; 151. Ratchet; 152. 1. Pawl; 153. Connecting shaft; 16. Adaptive driven assembly; 161. Drive drum; 162. Drive disc; 1621. Radial guide groove; 163. Centrifugal shoe; 164. Shoe tension spring; 2. Connecting mechanism; 21. Sealing plate; 22. Nut post; 3. External support mechanism; 4. Reset mechanism; 41. Mounting plate; 42. Clock spring; 43. Positioning pin; 44. Second protective cover; 5. Seat belt body. Detailed Implementation
[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0028] Example 1: As Figures 1 to 9 As shown, one embodiment of the present invention is a car seat belt retraction device with a pretensioning structure, comprising a pretensioning mechanism 1, a connecting mechanism 2, an external support mechanism 3, and a reset mechanism 4.
[0029] An opening is provided on one side of the pre-tightening mechanism 1, the connecting mechanism 2 is detachably installed on the open end of the pre-tightening mechanism 1, the outer support mechanism 3 is detachably installed on the side of the connecting mechanism 2 away from the pre-tightening mechanism 1, and the reset mechanism 4 is detachably installed on the side of the outer support mechanism 3 away from the connecting mechanism 2.
[0030] The pretensioning mechanism 1 includes an installation chamber 11, a first pretensioning component 13, a drive shaft 14, a second pretensioning component 15, and an adaptive driven component 16. The first pretensioning component 13 is installed inside the installation chamber 11 and is coaxially fixed with the drive shaft 14. The ratchet 151 of the second pretensioning component 15 is coaxially fixed with the drive shaft 14, and the second pretensioning component 15 is installed on the outside of the installation chamber 11. The adaptive driven component 16 is drivenly connected to the drive shaft 14 and is drivenly connected to the pawl 152 drive end of the second pretensioning component 15. Both the first pretensioning component 13 and the second pretensioning component 15 are configured to synchronously trigger locking as the drive shaft 14 rotates at high speed.
[0031] The connecting mechanism 2 includes a sealing plate 21 and multiple sets of nut columns 22. The sealing plate 21 covers the open end of the installation chamber 11 to seal the installation chamber 11. The nut columns 22 pass through the sealing plate 21. The installation chamber 11, the sealing plate 21, the external support mechanism 3 and the reset mechanism 4 are detachably connected in sequence through the nut columns 22.
[0032] The outer support mechanism 3 has holes that correspond to and match the nut column 22, and the drive shaft 14 passes through the inner side of the outer support mechanism 3.
[0033] The reset mechanism 4 includes a mounting plate 41 and a spring 42. The mounting plate 41 is threadedly connected to the nut post 22 by bolts. The spring 42 is mounted on the mounting plate 41 and is connected to the drive shaft 14 for driving the drive shaft 14 to complete the winding reset.
[0034] In this embodiment, the first pre-tightening component 13 can directly lock the transmission shaft 14 when it rotates at high speed, and the adaptive driven component 16 can drive the second pre-tightening component 15 to lock the transmission shaft 14 when it rotates at high speed. The two form two independent locking actuators, thus constructing a dual redundant locking protection structure.
[0035] Example 2: To clarify the specific implementation of the double pre-tightening locking structure and ensure the complete realization of the pre-tightening locking function, such as... Figures 3 to 9 As shown, this embodiment further defines the specific structure of the pre-tightening mechanism 1 based on embodiment 1.
[0036] The first pre-tightening assembly 13 includes an internal gear ring 131, a central turntable 133, two sets of centrifugal tooth blocks 134, and two sets of tooth block tension springs 135. The internal gear ring 131 is fixedly installed on the inner side wall of the mounting chamber 11, and the inner wall of the internal gear ring 131 is uniformly provided with limiting internal teeth 132 along the circumference. The central turntable 133 is coaxially arranged on the inner side of the internal gear ring 131, and the central turntable 133 is coaxially fixed to the transmission shaft 14 by a key connection. Two radial grooves 1331 are symmetrically provided on both sides of the central turntable 133, and the two sets of centrifugal tooth blocks 134 are slidably installed in the two radial grooves 1331 respectively. One end of the tooth block tension spring 135 is fixedly connected to the bottom of the radial groove 1331, and the other end is fixedly connected to the inner end of the centrifugal tooth block 134. The outer end of the centrifugal tooth block 134 can slide outward under the action of centrifugal force and mesh with the limiting internal teeth 132.
[0037] One end of the drive shaft 14 extends through the side wall of the mounting chamber 11 to the outside of the chamber, and the other end of the drive shaft 14 passes through the sealing plate 21, the outer support mechanism 3 and the mounting plate 41 in sequence. The section of the drive shaft 14 that passes through the mounting plate 41 is provided with a limit slot 141. The section of the drive shaft 14 located in the mounting chamber 11 is provided with an annular groove 142, and a synchronous belt 143 is sleeved in the annular groove 142.
[0038] The second preload assembly 15 includes a ratchet 151, a pawl 152, a connecting shaft 153, and a torsion spring. The ratchet 151 is coaxially and fixedly connected to one end of the drive shaft 14 extending outside the mounting chamber 11. The pawl 152 is disposed on one side of the ratchet 151, and the pawl end of the pawl 152 can mesh with the tooth groove of the ratchet 151. The connecting shaft 153 passes through the mounting hole of the pawl 152, and one end of the connecting shaft 153 is rotatably connected to the outer wall of the mounting chamber 11. The torsion spring is sleeved on the connecting shaft 151. 3. One end of the torsion spring is fixedly connected to the pawl 152, and the other end is fixedly connected to the connecting shaft 153, so that the pawl 152 remains separated from the ratchet 151 in a non-powered state; the other end of the connecting shaft 153 passes through the side wall of the mounting chamber 11 and is coaxially fixedly connected to the adaptive driven component 16; a first protective cover 12 is provided on the outside of the ratchet 151, and the first protective cover 12 is detachably connected to the mounting chamber 11 to protect the second pre-tightening component 15.
[0039] The adaptive driven assembly 16 includes a driven drum 161, a drive disc 162, multiple sets of centrifugal shoe blocks 163, and multiple sets of shoe block tension springs 164. The driven drum 161 is a cylindrical structure with one open end, and the outer center of the closed end of the driven drum 161 is welded and fixed to the connecting shaft 153. The drive disc 162 is rotatably mounted in the inner cavity of the driven drum 161. A driven wheel is coaxially fixed at the center of the side of the drive disc 162 opposite to the closed end of the driven drum 161. The other end of the synchronous belt 143 is sleeved on the driven wheel, so that the drive shaft 14... The drive disc 162 can be driven to rotate synchronously by the synchronous belt 143; multiple radial guide grooves 1621 are evenly opened on the outer side wall of the drive disc 162 along the circumference, and multiple sets of centrifugal shoes 163 are slidably installed in the multiple radial guide grooves 1621 respectively; one end of the shoe tension spring 164 is fixedly connected to the bottom of the radial guide groove 1621, and the other end is fixedly connected to the inner end of the centrifugal shoe 163. The outer end of the centrifugal shoe 163 can slide outward under the action of centrifugal force and form a friction mating surface with the inner wall of the driven drum 161.
[0040] The drive shaft 14 and the drive disc 162 are rotatably connected by bearings and sealing plate 21 to ensure coaxiality and stability during rotation.
[0041] Example 3: To clarify the assembly connection relationship of each mechanism and the implementation method of the reset function, such as... Figures 1 to 4 As shown, this embodiment further defines the specific structures of the connecting mechanism 2, the external support mechanism 3, and the reset mechanism 4 based on embodiment one.
[0042] The sealing plate 21 has multiple through holes evenly distributed along its circumference to match the nut posts 22. Multiple sets of nut posts 22 are respectively inserted into the corresponding through holes. One end of the nut post 22 is provided with an external thread. After passing through the through hole of the sealing plate 21, the end is threadedly fastened to the corresponding threaded hole on the side wall of the mounting chamber 11. The other end of the nut post 22 is a smooth rod section. The smooth rod section passes through the corresponding hole on the outer support mechanism 3 and the corresponding through hole on the mounting plate 41 of the reset mechanism 4 in sequence. The end of the smooth rod section is provided with an internal threaded hole. After the locking bolt passes through the through hole of the mounting plate 41, it is screwed into the internal threaded hole to thread-lock and fix the mounting plate 41 and the nut post 22.
[0043] The outer support mechanism 3 is an L-shaped frame structure. The two vertical side plates of the outer support mechanism 3 are respectively attached to the outer side of the sealing plate 21 and the inner side of the mounting plate 41. The inner cavity of the outer support mechanism 3 forms a receiving space to accommodate the seat belt body 5 wrapped on the drive shaft 14, so as to avoid external components interfering with the retraction and extension of the seat belt body 5.
[0044] The reset mechanism 4 also includes a positioning pin 43 and a second protective cover 44. The positioning pin 43 is vertically fixed on the end face of the mounting plate 41 facing the mainspring 42. The mainspring 42 is a planar spiral spring. The inner end of the mainspring 42 is snapped and fixed in the limiting groove 141 of the drive shaft 14, and the outer end of the mainspring 42 is snapped and fixed on the positioning pin 43. The positioning pin 43 cooperates with the limiting groove 141 to complete the limiting installation of the mainspring 42. The second protective cover 44 is snapped and installed on the side of the mounting plate 41 away from the outer support mechanism 3. The inner cavity of the second protective cover 44 covers the installation area of the mainspring 42 to limit the axial movement of the mainspring 42 on the mounting plate 41 and at the same time form a closed protection for the mainspring 42.
[0045] Example 4: To clarify the working principle of this device, such as Figures 1 to 9 As shown, this embodiment supplements the above embodiment with a matching seat belt body 5 structure, and provides a complete description of the working process of the device.
[0046] The device also includes a seat belt body 5. One end of the seat belt body 5 is fixedly connected to the rod wall of the drive shaft 14, and the seat belt body 5 is wrapped around the drive shaft 14 in the circumferential direction. The other end of the seat belt body 5 passes through the frame gap of the outer support mechanism 3 and is connected to the seat belt locking tongue.
[0047] In normal use, the user slowly pulls the protruding end of the seat belt body 5, causing the drive shaft 14 to rotate slowly. At this time, the central turntable 133 rotates slowly synchronously with the drive shaft 14. The centrifugal force on the centrifugal tooth block 134 is less than the tension of the tooth block tension spring 135. The centrifugal tooth block 134 is housed in the radial groove 1331 and does not mesh with the limiting inner tooth 132. The first pretensioning component 13 does not trigger locking. At the same time, the drive shaft 14 drives the drive disc 162 to rotate slowly synchronously via the synchronous belt 143. The centrifugal force on the 3 is less than the tension of the shoe block spring 164. The centrifugal shoe block 163 is housed in the radial guide groove 1621 and does not contact the inner wall of the driven drum 161. The driven drum 161 remains stationary. The pawl 152 remains separated from the ratchet 151 under the elastic force of the torsion spring. The second pretensioning component 15 does not trigger the locking, and the seat belt body 5 can be smoothly pulled out. When the seat belt body 5 is released, the spring 42 releases its elastic potential energy, driving the transmission shaft 14 to rotate in the opposite direction, thereby realizing the automatic winding and reset of the seat belt body 5.
[0048] In a vehicle collision, the occupant's forward momentum causes the seatbelt body 5 to be pulled rapidly, causing the drive shaft 14 to rotate at high speed instantaneously. At this time, the central turntable 133 rotates synchronously at high speed with the drive shaft 14. The centrifugal force on the centrifugal tooth block 134 is greater than the tension of the tooth block tension spring 135. The centrifugal tooth block 134 is thrown outward along the radial groove 1331, and its outer end meshes with the limiting inner teeth 132 on the inner wall of the inner gear ring 131, locking the central turntable 133 and the inner gear ring 131 together, directly restricting the continued rotation of the drive shaft 14, completing the first pre-tensioning lock. At the same time, the drive shaft 14 is connected to the same... The belt 143 drives the drive disc 162 to rotate synchronously at high speed. The centrifugal shoe 163 is subjected to a centrifugal force greater than the tension of the shoe spring 164. The centrifugal shoe 163 is thrown outward along the radial guide groove 1621. Its outer end is tightly attached to the inner wall of the driven drum 161. Through friction, the driven drum 161 is driven to rotate synchronously. The driven drum 161 drives the pawl 152 to rotate against the elastic force of the torsion spring through the connecting shaft 153. The pawl end of the pawl 152 is engaged in the tooth groove of the ratchet 151 and locked with the ratchet 151. This forms a second locking limit on the drive shaft 14 and completes double pre-tightening protection.
[0049] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0050] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A car seatbelt retraction device with a pretensioning structure, comprising a pretensioning mechanism (1), a drive shaft (14), and a reset mechanism (4), characterized in that: The pretensioning mechanism (1) includes a first pretensioning component (13), a second pretensioning component (15), and an adaptive driven component (16). The first pre-tightening component (13) is coaxially fixed with the transmission shaft (14). The first pre-tightening component (13) is a centrifugal locking structure, which is configured to trigger locking when the transmission shaft (14) rotates at high speed, directly restricting the circumferential rotation of the transmission shaft (14). The second preload assembly (15) includes a ratchet (151) and a pawl (152). The ratchet (151) is coaxially fixed with the drive shaft (14), and the pawl (152) can engage with the ratchet (151) to limit the circumferential rotation of the drive shaft (14). The adaptive driven component (16) is connected to the drive shaft (14) and the power output end of the adaptive driven component (16) is connected to the drive end of the pawl (152). The adaptive driven component (16) is a centrifugal drive structure and is configured to drive the pawl (152) to mesh with the ratchet (151) as the drive shaft (14) rotates at high speed. The first pretensioning component (13) and the second pretensioning component (15) form two sets of independent and synchronously triggered locking actuators, constituting a dual redundant locking protection structure; The reset mechanism (4) is connected to the drive shaft (14) and is used to drive the drive shaft (14) to complete the rewinding and reset of the seat belt.
2. The automotive seatbelt retraction device with a pre-tensioning structure according to claim 1, characterized in that, The pre-tightening mechanism (1) further includes an installation chamber (11), with an opening on one side; the first pre-tightening component (13) is installed inside the installation chamber (11), the second pre-tightening component (15) is installed outside the installation chamber (11), and the adaptive driven component (16) is installed in the internal cavity of the installation chamber (11).
3. A car seatbelt retraction device with a pretensioning structure according to claim 2, characterized in that, The first pre-tensioning assembly (13) includes an internal gear ring (131), a central turntable (133), two sets of centrifugal gear blocks (134), and two sets of gear block tension springs (135). The internal gear ring (131) is fixedly installed on the inner side wall of the mounting chamber (11), and the inner wall of the internal gear ring (131) has circumferentially circumferentially provided limiting internal teeth (132). The central turntable (133) is coaxially arranged inside the internal gear ring (131), and the central turntable (133) and the drive shaft (14) are aligned. The shaft is fixed, and two radial grooves (1331) are symmetrically opened on both sides of the central turntable (133). Two sets of centrifugal tooth blocks (134) are slidably installed in the two radial grooves (1331). One end of the tooth block tension spring (135) is fixedly connected to the bottom of the radial groove (1331), and the other end of the tooth block tension spring (135) is fixedly connected to the inner end of the centrifugal tooth block (134). The outer end of the centrifugal tooth block (134) can mesh with the limiting inner tooth (132).
4. A car seatbelt retraction device with a pre-tensioning structure according to claim 2, characterized in that, The second pre-tightening assembly (15) also includes a connecting shaft (153) and a torsion spring; the pawl (152) is disposed on one side of the ratchet (151); the connecting shaft (153) passes through the mounting hole of the pawl (152), and one end of the connecting shaft (153) is rotatably connected to the outer wall of the mounting chamber (11); the torsion spring is sleeved on the connecting shaft (153), one end of the torsion spring is fixedly connected to the pawl (152), and the other end of the torsion spring is fixedly connected to the connecting shaft (153), and the torsion spring is used to keep the pawl (152) separated from the ratchet (151) in a non-powered state; the other end of the connecting shaft (153) passes through the side wall of the mounting chamber (11) and is coaxially fixedly connected to the adaptive driven assembly (16); a first protective cover (12) is provided on the outside of the ratchet (151), and the first protective cover (12) is detachably connected to the mounting chamber (11).
5. A car seatbelt retraction device with a pre-tensioning structure according to claim 4, characterized in that, The adaptive driven assembly (16) includes a driven drum (161), a drive disc (162), multiple sets of centrifugal shoe blocks (163), and multiple sets of shoe block tension springs (164); the driven drum (161) is a cylindrical structure with one open end, and the outer center of the closed end of the driven drum (161) is fixedly connected to the connecting shaft (153); the drive disc (162) is rotatably mounted in the inner cavity of the driven drum (161), and the outer wall of the drive disc (162) is along... Multiple radial guide grooves (1621) are opened in the circumferential direction, and multiple centrifugal shoe blocks (163) are slidably installed in the multiple radial guide grooves (1621); one end of the shoe block tension spring (164) is fixedly connected to the bottom of the radial guide groove (1621), and the other end of the shoe block tension spring (164) is fixedly connected to the inner end of the centrifugal shoe block (163). The outer end of the centrifugal shoe block (163) can form a friction mating surface with the inner wall of the driven drum (161).
6. A car seatbelt retraction device with a pre-tensioning structure according to claim 5, characterized in that, The drive disc (162) has a driven wheel coaxially fixed at the center of the side opposite to the closed end of the driven drum (161); the shaft of the transmission shaft (14) has an annular groove (142) and a synchronous belt (143) is sleeved in the annular groove (142), and the other end of the synchronous belt (143) is sleeved on the driven wheel.
7. A car seatbelt retraction device with a pre-tensioning structure according to claim 2, characterized in that, The open end of the installation chamber (11) is covered with a sealing plate (21), and the drive shaft (14) and the drive disc (162) are rotatably connected to the sealing plate (21) through bearings.
8. A car seatbelt retraction device with a pretensioning structure according to claim 1, characterized in that, The reset mechanism (4) includes a mounting plate (41), a spring (42), a positioning pin (43), and a second protective cover (44). The spring (42) is mounted on the mounting plate (41), and the positioning pin (43) is vertically fixed on the end face of the mounting plate (41) facing the spring (42). The drive shaft (14) passes through the rod section of the mounting plate (41) and has a limiting slot (141). The inner end of the spring (42) is fixed in the limiting slot (141), and the outer end of the spring (42) is fixed in the positioning pin (43). The second protective cover (44) is fastened to the outside of the mounting plate (41) and covers the mounting area of the spring (42).
9. A car seatbelt retraction device with a pretensioning structure according to claim 8, characterized in that, It also includes a connecting mechanism (2) and an external support mechanism (3); the connecting mechanism (2) includes a sealing plate (21) and multiple sets of nut columns (22), the nut columns (22) are inserted through the sealing plate (21), and the installation chamber (11), sealing plate (21), external support mechanism (3) and reset mechanism (4) are sequentially and detachably connected through the nut columns (22); the external support mechanism (3) has holes that correspond to and match the nut columns (22), and the drive shaft (14) is inserted through the inner side of the external support mechanism (3); the external support mechanism (3) is L The frame structure has two vertical side plates of the outer support mechanism (3) that are respectively attached to the outer side of the sealing plate (21) and the inner side of the mounting plate (41); one end of the nut column (22) is provided with an external thread, and the end of the nut column (22) with the external thread passes through the through hole of the sealing plate (21) and is threadedly fastened to the threaded hole of the side wall of the mounting chamber (11); the other end of the nut column (22) passes through the corresponding hole of the outer support mechanism (3) and the corresponding through hole of the mounting plate (41) in sequence, and is threadedly locked to the mounting plate (41) by bolts.
10. A car seatbelt retraction device with a pretensioning structure according to claim 9, characterized in that, It also includes a seat belt body (5), one end of which is fixedly connected to the rod wall of the drive shaft (14), the seat belt body (5) is wrapped around the drive shaft (14) in the circumferential direction, and the other end of the seat belt body (5) passes through the frame gap of the outer support mechanism (3).