CN209813917U - Safety belt retractor - Google Patents

Abstract

The utility model provides a safety belt retractor, which comprises a frame, a scroll, a locking block and a locking assembly, wherein the frame is provided with a rotating hole, ratchet teeth are carved on the inner wall of the rotating hole, the scroll is arranged in the rotating hole, the locking block comprises a locking block main body and a convex column, the locking block main body is provided with locking teeth which are matched with the ratchet teeth, the end part of the scroll is provided with a reset spring, the locking assembly comprises an inner ratchet wheel, a fast inertia and a locking plate, the side wall of the inner ratchet wheel is protruded to form a spring reset column, the reset spring is supported on the spring reset column, the side wall of the fast inertia is provided with reset single teeth corresponding to the locking plate, the inner wall of the locking plate is carved with braking teeth which are meshed with the reset single teeth, the locking block main body is reset when rotating by utilizing the reset spring and the inner ratchet wheel, meanwhile, the reset single teeth on the fast inertia reset under the stirring of the braking teeth, finally guarantee that the canceling release mechanical system of coiler can even running, the life of coiler increases.

Description

Safety belt retractor

Technical Field

The utility model relates to a coiler technical field especially relates to a safety belt coiler.

Background

When the retractor of the safety belt is used, the retractor usually has an emergency locking function, mainly comprises reaction processes such as spring recovery, vehicle inclination induction, vehicle rapid acceleration and deceleration induction, webbing acceleration induction and the like, and the retractor can lock the safety belt internally after the acceleration reaches a threshold value when the safety belt is drawn out, so that the safety belt is prevented from being continuously pulled out. Thereby the length that the restriction safety belt was taken out for personnel can be protected by the safety belt of certain distance in the car, and the safety belt is taking out the back, because the coiler is after long-time use, is difficult for withdrawing behind the urgent locking, specifically is behind the urgent locking, and the restriction mechanism can not reset to initial position, and the safety belt very easily blocks extremely in the coiler promptly, influences the use of coiler.

SUMMERY OF THE UTILITY MODEL

Based on the above reason, the utility model provides a can help safety belt coiler that the limiting mechanism resets.

The utility model provides a technical scheme that its technical problem adopted is: a safety belt retractor comprises a frame, a reel, a locking block and a locking assembly, wherein a rotating hole is formed in the frame, ratchet teeth are carved on the inner wall of the rotating hole, the reel is arranged in the rotating hole, the locking block comprises a locking block main body and a convex column, the locking block main body is movably inserted into the end portion of the reel, the convex column is fixedly connected onto the locking block main body, the locking block main body is provided with locking teeth matched with the ratchet teeth, the convex column slides in the direction of the end portion of the reel, the end portion of the reel is provided with a reset spring which is abutted against the locking assembly, the locking assembly comprises an inner ratchet wheel, an inertia block and a locking plate, a spring reset column is formed on the side wall of the inner ratchet wheel in a protruding mode, the reset spring is abutted against the spring reset column, the inertia block is rotatably arranged in the inner ratchet wheel, reset single teeth corresponding to the locking plate are arranged on the side wall of the inertia block, and brake teeth meshed with the reset single teeth are carved on the inner wall of the locking plate.

Further, the tip of spool is opened have with the locking block nest that the locking block main part corresponds, the notch of locking block nest with ratchet tooth corresponds, the tip of spool has still opened the locking block reset groove, the locking block reset groove with the locking block nest is the same, the locking block main part accept in the locking block nest, projection cooperation alternates in the locking block reset groove.

Furthermore, a spring groove is formed in the end face of the reel, the return spring is arranged in the spring groove in a matching mode, one end of the return spring abuts against the groove wall of the spring groove, and the other end of the return spring abuts against the spring return column.

Furthermore, the inner ratchet wheel is in a hollow cylinder shape, the spring reset column is arranged on the bottom wall of the inner ratchet wheel, a control tooth groove is formed in the bottom wall of an inner cavity of the inner ratchet wheel, and the convex column is inserted into the control tooth groove.

Further, the inertia is fast and is the fan-shaped form, the setting of the monodentate that resets is in on the fast curved surface of inertia, the both ends that inertia is fast extend respectively and are equipped with locking and support board and limit journey bent plate, the both sides that the locking supported the board are provided with inertia piece limit journey post and restriction post, the restriction post sets up the control tooth's socket is kept away from the notch department of spool, the locking support board rotate the back with the braking tooth supports each other and holds.

Furthermore, the travel limiting bent plate protrudes towards the direction of the inertia block limiting column to form a spring protrusion, a spring base corresponding to the spring protrusion is arranged in the inner ratchet wheel, and an inertia spring is arranged between the spring base and the spring protrusion.

Furthermore, an inertia block rotating column matched with the rotating hole is formed on the inner ratchet wheel in a protruding mode, and the inertia block rotating column is rotatably arranged on the inner ratchet wheel through the inertia block rotating column.

Further, the locking plate includes retainer plate, ratchet wheel circle and the sealing washer that sets gradually by outer to interior, a plurality of fixed plates of the outer fixedly connected with of retainer plate, the fixed plate is followed the retainer plate outer wall evenly distributed, the fixed plate is fixed extremely on the frame, the setting of brake tooth is in on the inner wall of ratchet wheel circle, the sealing washer can establish with rotating relatively on the spool.

Furthermore, the fixed plate is formed with the deformation post to the frame direction protrusion, deformation groove has been seted up to the deformation post axial, after the deformation post pierces through the frame, the deformation groove resets after contracting, the locking plate passes through the deformation post block is fixed to on the frame.

Furthermore, the section diameter of the fixing ring is larger than the outer diameter of the inner ratchet wheel, and the section diameter of the ratchet wheel ring is smaller than the inner diameter of the inner ratchet wheel.

The beneficial effects of the utility model are that, set up reset spring in the coiler, push away under reset spring, the ratchet drives the projection rotation in the locking subassembly, make the projection at locking piece reset groove internal backsliding, locking tooth in the locking piece main part breaks away from ratchet tooth promptly, the rotational degree of freedom release of the relative frame of spool, the safety belt can be withdrawed to the spool on, utilize pushing away of inertia spring to and the stirring of braking tooth to the monodentate that resets on the locking plate, inertia resets soon to initial position, with the help of reset spring, inertia spring and reset monodentate, make the inertia in the coiler fast with the locking piece main part can be timely reset to initial position, the use of the coiler of being convenient for.

Drawings

The present invention will be further explained with reference to the drawings and examples.

Fig. 1 is a perspective view of a retractor according to the present invention;

FIG. 2 is an exploded view of the retractor of FIG. 1 as assembled;

fig. 3 is another perspective view of the retractor shown in fig. 2 (with the single-sided mechanical cover omitted);

fig. 4 is another perspective view of the retractor shown in fig. 3 (with the locking plate omitted);

fig. 5 is another perspective view of the retractor shown in fig. 4 (with the locking assembly omitted);

fig. 6 is an exploded view of the assembly of the locking assembly in the retractor of the present invention;

in the figure:

seat belt retractor 100 frame 1 rotation hole 11

Ratchet teeth 12 spool 2 accommodating block 21

Return channel 213 for detent 212 of detent 211 detent

Limiting plate 23 of spring groove 214 limiting ring 22

Fixing hole 24 braid through groove 25 locking block 3

Locking block body 31, boss 32 and locking teeth 33

Ratchet wheel 41 control tooth slot 411 in locking assembly 4

Spring return post 412 inertial mass rotation post 413 inertial mass limit post 414

Inertial mass travel limit post 415 rotation sleeve 416 spring mount 417

Inertia block pressing block 418 inertia block 42 locking abutting plate 421

Limit bent plate 422 reset single tooth 423 abdicating groove 424

Spring protrusion 425 locking plate 43 position limiting cover 431

Sealing ring 433 fixing plate 434 of ratchet ring 432

Fastening foot 435 mechanical cover 5 reset spring 6

Inertia spring 7

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention. On the contrary, the embodiments of the invention include all changes, modifications and equivalents coming within the spirit and terms of the claims appended hereto.

As shown in fig. 1 to 6, the utility model provides a safety belt retractor 100, including frame 1, spool 2, locking piece 3, locking subassembly 4 and mechanical lid 5, spool 2 rotationally alternates inside frame 1, and locking piece 3 and locking subassembly 4 all set up the tip at spool 2, and mechanical lid 5 is fixed on the side of frame 1 external symmetry. The safety belt is wound on the reel 2, and the rotation of the reel 2 relative to the frame 1 is controllably interfered by the locking block 3 and the locking assembly 4, so that the process of extending and retracting the safety belt is controlled by sudden stop.

Frame 1 is U type plate structure, all opens on the both sides inner wall of symmetry on the frame 1 and has rotated hole 11, and spool 2 rotationally installs on frame 1 through rotating hole 11, is carved with ratchet tooth 12 on the inner wall of the rotation hole 11 of frame 1 one side.

As shown in fig. 1, the winding shaft 2 is substantially cylindrical, two ends of the winding shaft 2 are rotatably inserted into the rotation holes 11, one end of the winding shaft 2 is fixedly provided with an accommodating block 21, the other end of the winding shaft is fixedly provided with a limiting ring 22, the limiting ring 22 is hollow cylindrical, the outer circumferential surface of the limiting ring 22 is recessed inwards to form a groove, the width of the groove is greater than the wall thickness of the frame 1, and the limiting ring 22 is rotatably clamped in the rotation holes 11 of the frame 1 through the groove. The reel 2 is also fixedly provided with a limiting plate 23, the accommodating block 21 is fixed on the limiting plate 23, the minimum section size of the limiting plate 23 is larger than the aperture of the rotating hole 11, and the limiting plate 23 can be attached to the inside of the frame 1 in a relatively rotating mode. The reel 2 is provided with a plurality of fixing holes 24 and a braid through groove 25 on the circumferential surface between the limiting ring 22 and the limiting plate 23, a coil spring (not shown) is arranged in the braid through groove 25, one end of the coil spring is fixed on the inner wall of the braid through groove 25, the other end of the coil spring is fixed on the frame 1 through the reel 2, the fixing holes 24 are arranged near the notch of the braid through groove 25, and the end part of the safety belt is fixed in the fixing holes 24.

The accommodating block 21 corresponds to the ratchet teeth 12 on the frame 1, the accommodating block 21 is substantially cylindrical, the end face of the accommodating block 21 is attached to the end face of the reel 2, a rotating shaft 211 is fixedly mounted at the center position of the accommodating block 21, and the rotating shaft 211 is arranged in a direction away from the limit plate 23. The end face of the adjacent limiting plate 23 on the accommodating block 21 is provided with a lock block nest 212, the lock block nest 212 is a special-shaped groove, the lock block nest 212 is roughly in a non-uniform semi-crescent shape, the inner end of the lock block nest 212 is in a corner shape and is arranged in the accommodating block 21, the groove wall of the lock block nest 212 and the circumferential face of the accommodating block 21 are in an intersecting shape, understandably, the notch of the lock block nest 212 is arranged on the circumferential face of the accommodating block 21, and the lock block nest 212 inwards extends into a crescent shape from the circumferential face of the accommodating block 21. The end face, far away from limiting plate 23, of accommodating block 21 is provided with a locking block reset groove 213 communicated with locking block nest 212, locking block reset groove 213 is a curved waist-shaped through groove in the wall of locking block nest 212, locking block reset groove 213 extends inwards from the edge of the end face of accommodating block 21, and the groove length of locking block reset groove 213 is greater than the distance between accommodating block 21 and rotating hole 11. Spring groove 214 is further formed in the same side face of accommodating block 21 and locking block reset groove 213, and reset spring 6 is installed in spring groove 214 in a matched mode.

Referring to fig. 2 and 5, the locking block 3 includes a locking block main body 31 and a convex pillar 32 convexly disposed on the locking block main body 31, the locking block main body 31 is a block-shaped stretching body corresponding to the shape of the locking block nest 212, the locking block main body 31 is removably received in the locking block nest 212, the curved sidewall of the locking block main body 31 is provided with a locking tooth 33, the locking tooth 33 and the ratchet tooth 12 on the frame 1 are in a engageable relationship, the convex pillar 32 is movably disposed in the locking block reset groove 213, it will be appreciated that after the portion of the lock block body 31 carrying the locking teeth 33 is removed from the lock block nest 212, after the locking teeth 33 are moved out, the locking teeth are mutually meshed with the ratchet teeth 12, the locking block main body 31 is limited and clamped on the groove wall of the rotating hole 11, the spool 2 and the receiving block 21 no longer rotate relative to the frame 1 under the restriction that the lock block body 31 is received in the inner portion of the lock block nest 212.

As shown in fig. 2, 3, 4 and 6, the locking assembly 4 includes an inner ratchet wheel 41, an inertia block 42 and a locking plate 43, the inner ratchet wheel 41 is in an open tubular shape, the inner ratchet wheel 41 is relatively rotatably sleeved on the reel 2, the inner ratchet wheel 41 is attached to an end surface of the accommodating block 21, an opening of the inner ratchet wheel 41 is arranged in a direction away from the accommodating block 21, and a maximum cross-sectional diameter of the inner ratchet wheel 41 is larger than a bore diameter of the rotating hole 11.

The inner ratchet wheel 41 is provided with a control tooth groove 411, the control tooth groove 411 is a curved waist-shaped groove corresponding to the locking block reset groove 213, the bending direction of the control tooth groove 411 is opposite to that of the locking block reset groove 213, the directions of the control tooth groove 411 and the locking block reset groove 213 are the same, and the convex column 32 is movably inserted in the control tooth groove 411 and the locking block reset groove 213. The inner ratchet wheel 41 and the side wall adjacent to the accommodating block 21 are fixedly provided with a spring return column 412, the spring return column 412 is a column body formed by protruding from the inner ratchet wheel 41 to the accommodating block 21, the end part of the spring return column 412 is arranged in the spring groove 214, the spring return column 412 is abutted against the end part of the return spring 6, the spring return column 412 is attached to the groove wall of the end part of the spring groove 214, and the direction of the return spring 6 pointing to the spring return column 412 is the same as the rotating direction of the reel 2 when outputting the safety belt. An inertia block rotating column 413, an inertia block limiting column 414, an inertia block distance limiting column 415, a rotating sleeve 416 and a spring base 417 are fixedly installed on the side wall of the inner ratchet wheel 41 far away from the accommodating block 21, the rotating sleeve 416 is sleeved on the rotating shaft 211, and an inertia block pressing block 418 is fixedly arranged at the end part, far away from the limiting plate, of the rotating sleeve 416. The centers of the inertia block rotating column 413, the inertia block pressing block 418 and the rotating sleeve 416 are collinear, the inertia block limiting column 414 is arranged at the notch of the control tooth slot 411, the inertia block stroke limiting column 415 and the inertia block limiting column 414 are adjacently arranged, and the inertia block stroke limiting column 415 is arranged on the side edge of the inertia block limiting column 414 far away from the control tooth slot 411.

The fast 42 of inertia is approximately fan-shaped plate-shaped stretching body, and the fast 42 of inertia rotatable cover is established on inertia piece rotation post 413, and the both ends of the fast 42 of inertia extend respectively and are equipped with locking and support board 421 and range limiting bent plate 422, are equipped with the monodentate 423 that resets on the curved surface of the fast 42 of inertia, and the straight side on the fast 42 of inertia is adjacent with rotating sleeve 416, and it has the groove of stepping down 424 to open on the straight side of rotating sleeve 416, and the groove of stepping down 424 sets up along the tensile direction of the fast 42 of inertia. The cross-sectional shape of the abdicating groove 424 is the same as that of the inertia block pressing block 418, the inertia block pressing block 418 is arranged at the notch of the abdicating groove 424 far away from the control tooth slot 411, and the cross-sectional dimension of the inertia block pressing block 418 is larger than that of the abdicating groove 424. The end face of the inertia block 42 is provided with a linkage hole (not shown) along the stretching direction, and the linkage hole is sleeved on the inertia block rotating column 413 in a clearance fit manner. The locking abutting plate 421 is a plate body extending along the straight side surface of the inertia block 42, the outer end of the locking abutting plate 421 is in a sharp angle shape, and the locking abutting plate 421 is movably arranged between the inertia block limiting column 414 and the inertia block distance limiting column 415. The stroke limiting curved plate 422 is a semi-surrounding curved plate extending along the curved surface of the inertia block 42, the bending direction of the stroke limiting curved plate 422 is opposite to the rotating direction of the rotating shaft 211 when the safety belt is pulled out, a spring bulge 425 is fixedly installed in the stroke limiting curved plate 422, the spring bulge 425 is arranged on the straight side surface of the inertia block 42, the spring bulge 425 corresponds to the spring base 417, an inertia spring 7 is arranged between the spring bulge 425 and the spring base 417 in a supporting manner, and the stroke limiting curved plate 422 is arranged near the inertia spring 7 in a semi-surrounding state.

The locking plate 43 comprises a limiting cover 431, a ratchet ring 432 and a sealing ring 433, the ratchet ring 432 and the sealing ring 433 are fixed in the limiting cover 431 in a ring strip shape, the section diameter of the limiting cover 431 is larger than the outer diameter of the inner ratchet 41, the limiting cover 431 covers the inner ratchet 41, a plurality of fixing plates 434 are fixedly connected to the outer portion of the limiting cover 431, the fixing plates 434 are uniformly arranged along the circumferential direction of the limiting cover 431, clamping legs 435 are fixedly connected to the fixing plates 434, and the clamping legs 435 are fixed on the side wall of the frame 1. The section diameter of the ratchet ring 432 is smaller than the inner diameter of the inner ratchet wheel 41, the ratchet ring 432 and the limiting cover 431 are respectively clamped and arranged on the inner side and the outer side of the inner ratchet wheel 41, the inner wall of the ratchet ring 432 is carved with braking teeth 436, the reset single tooth 423 and the locking abutting plate 421 can abut against the braking teeth 436 after rotating, and the sealing ring 433 can be sleeved on the rotating shaft 211 of the accommodating block 21 in a relatively rotating manner.

After the retractor is mounted on a vehicle body, a safety belt is wound on the reel 2 and then connected to the coil spring in the fixing hole 24, the safety belt is controllably pulled out of the frame 1, in the process of pulling out the safety belt, the locking plate 43 rotates along with the rotating shaft 211 on the accommodating block 21, under the combined action of a centrifugal force field and the elastic potential energy of the inertia spring when the locking plate 43 rotates, the inertia block 42 rotates around the inertia block rotating column 413, and specifically, after the centrifugal force is greater than the elastic force of the inertia spring, the inertia spring 7 contracts after being extruded. The locking resisting plate 421 moves from the inertia block limiting column 414 to the inertia block limiting column 415, the minimum distance between the locking resisting plate 421 and the locking plate 43 decreases, and similarly, the minimum distance between the reset single tooth 423 and the locking plate 43 also decreases until the reset single tooth 423 and the locking resisting plate 421 rotate and then abut against the braking tooth 436, since the locking plate 43 is fixed on the frame 1 through the fastening foot 435, the inertia block 42 is subjected to the reaction force of the braking tooth 436, the inertia block 42 does not rotate around the rotating shaft 211 along with the inner ratchet wheel 41, the inertia block rotating column 413 in the inertia block 42 is fixedly connected with the inner ratchet wheel 41, and the inner ratchet wheel 41 stops rotating under the limitation of the inertia block 42.

After the inner ratchet wheel 41 stops rotating, the reel 2 continues rotating under the traction of the safety belt, when the reset spring 6 rotates, the reset spring is clamped and pressed by the spring reset column 412 and the spring groove 214, elastic potential energy under a contraction state is accumulated, the top of the convex column 32 in the lock block 3 is limited by the control toothed groove 411 and can only move along the control toothed groove 411, the bottom of the convex column 32 is limited by the lock block reset groove 213, a movement trend following the rotation of the accommodating block 21 is generated, under the limitation of the lock block reset groove 213 and the control toothed groove 411, the convex column 32 generates a stroke moving towards the edge of the accommodating block 21 along the control toothed groove 411 and the lock block reset groove 213 in the movement, under the traction of the convex column 32, the lock block main body 31 is partially moved out of the lock block nest 212 until the locking teeth 33 on the lock block main body 31 are meshed with the ratchet teeth 12, under the limitation of the meshing relation between the locking teeth 33 and the ratchet teeth 12, the lock block body 31 stops following the rotation of the accommodating block 21, and the accommodating block 21 is reacted by the lock block body 31 to stop the rotation process, and at this time, the rotation process of the reel 2 is stopped under the limit of the accommodating block 21 and is not rotated any more.

After the force for pulling out the safety belt disappears, the reel 2 starts to rotate reversely under the action of the coil spring, the convex column 32 is pushed by the reset groove 213 of the locking block on the containing block 21 and moves towards the inside of the containing block 21 along the control tooth socket 411, the locking block main body 31 is contained in the locking block nest 212, the locking tooth 33 is separated from the ratchet tooth 12, the reel 2 is controlled by the unlocking frame 1, and the elastic potential energy of the reset spring 6 after contraction is released in the resetting process, pushing the spring return post 412, the spring return post 412 drives the inner ratchet 41 to rotate a certain angle along the direction of pulling out the safety belt, while the cooperating lock block body 31 is retracting the lock block nest 212, the inner ratchet 41 drives the inertia block 42 to rotate relative to the lock plate 43, under the pushing action of the inertia spring, the locking abutting plate 421 on the inertia block 42 is disengaged from the braking teeth 436, and finally the unlocking process of the reel 2 is completed.

After the rotation process is stopped, the inertia spring 7 pushes the inertia block 42 to rotate reversely on the inertia block rotation column 413, the locking resisting plate 421 is separated from the braking teeth 436, in the locking process of unlocking the safety belt, the inertia spring 7 loses elasticity, and when the inertia block 42 cannot be pushed, the inertia block 42 can be reset to the initial position by rotating the inner ratchet wheel 41 and the reset single tooth 423 under the stirring of the braking teeth 436, namely, the reset single tooth 423 can replace the inertia spring 7 to realize the function of auxiliary return.

In light of the foregoing, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims (10)

1. A seatbelt retractor, comprising: the locking mechanism comprises a frame, a reel, a locking block and a locking assembly, wherein a rotating hole is formed in the frame, ratchet teeth are carved on the inner wall of the rotating hole, the reel is arranged in the rotating hole, the locking block comprises a locking block main body movably inserted at the end part of the reel and a convex column fixedly connected to the locking block main body, locking teeth matched with the ratchet teeth are formed in the locking block main body, the convex column slides in the end part of the reel in a directional manner, a reset spring abutted against the locking assembly is arranged at the end part of the reel, the locking assembly comprises an inner ratchet wheel, an inertia block and a locking plate, a spring resetting column is formed on the side wall of the inner ratchet wheel in a protruding manner, the reset spring is abutted against the spring resetting column, the inertia block is rotatably arranged in the inner ratchet wheel, and reset single teeth corresponding to the locking plate are arranged on the side wall of the inertia block, and brake teeth meshed with the reset single teeth are carved on the inner wall of the locking plate.

2. The seatbelt retractor according to claim 1, wherein: the tip of spool open have with the locking block nest that the locking block main part corresponds, the notch of locking block nest with ratchet tooth corresponds, the tip of spool has still opened locking block reset groove, the locking block reset groove with the locking block nest is the same, the locking block main part accept in the locking block nest, projection cooperation alternates in the locking block reset groove.

3. The seatbelt retractor according to claim 2, wherein: the end face of the reel is also provided with a spring groove, the reset spring is arranged in the spring groove in a matching mode, one end of the reset spring abuts against the groove wall of the spring groove, and the other end of the reset spring abuts against the spring reset column.

4. The seatbelt retractor according to claim 1, wherein: the inner ratchet wheel is in a hollow cylindrical shape, the spring reset column is arranged on the bottom wall of the inner ratchet wheel, a control tooth groove is formed in the bottom wall of an inner cavity of the inner ratchet wheel, and the convex column is inserted into the control tooth groove.

5. The seatbelt retractor according to claim 4, wherein: the quick inertia is fan-shaped, the setting of the monodentate that resets is in on the quick curved surface of inertia, the quick both ends of inertia extend respectively and are equipped with locking butt plate and range limiting bent plate, the both sides of locking butt plate are provided with inertia piece range limiting post and restriction post, the restriction post sets up the control tooth's socket is kept away from the notch department of spool, the locking butt plate rotate the back with the braking tooth supports each other and holds.

6. The seatbelt retractor according to claim 5, wherein: the range limiting bent plate protrudes towards the direction of the inertia block limiting column to form a spring bulge, a spring base corresponding to the spring bulge is arranged in the inner ratchet wheel, and an inertia spring is arranged between the spring base and the spring bulge.

7. The seatbelt retractor according to claim 6, wherein: an inertia block rotating column matched with the rotating hole is formed on the inner ratchet wheel in a protruding mode, and the inertia block rotating column can be rotatably arranged on the inner ratchet wheel through the inertia block rotating column.

8. The seatbelt retractor according to claim 1, wherein: the locking plate comprises a fixing ring, a ratchet ring and a sealing ring which are sequentially arranged from outside to inside, the fixing ring is fixedly connected with a plurality of fixing plates, the fixing plates are uniformly distributed on the outer wall of the fixing ring and fixed to the frame, the braking teeth are arranged on the inner wall of the ratchet ring, and the sealing ring is sleeved on the scroll in a relatively rotatable manner.

9. The seatbelt retractor according to claim 8, wherein: the fixed plate to the frame direction protrusion is formed with the deformation post, deformation groove has been seted up to the deformation post axial, the deformation post pierces through behind the frame, the deformation groove resets after contracting, the lock plate passes through the deformation post block is fixed extremely on the frame.

10. The seatbelt retractor according to claim 9, wherein: the section diameter of the fixed ring is larger than the outer diameter of the inner ratchet wheel, and the section diameter of the ratchet wheel rim is smaller than the inner diameter of the inner ratchet wheel.