CN112389364B

CN112389364B - Seat belt retractor and vehicle

Info

Publication number: CN112389364B
Application number: CN201910760756.9A
Authority: CN
Inventors: 李鑫
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2019-08-16
Filing date: 2019-08-16
Publication date: 2022-03-18
Anticipated expiration: 2039-08-16
Also published as: CN112389364A

Abstract

The present disclosure relates to a retractor for a seat belt and a vehicle. The winder comprises a frame, a support, a pre-tensioning mechanism, a winding gear, a locking gear and a locking mechanism, wherein the frame is used for being installed on a vehicle body of a vehicle, the support is arranged on the frame, the pre-tensioning mechanism is arranged on the support, the winding gear and the locking gear are connected with a winding drum and can rotate integrally, the locking mechanism is used for preventing the winding drum from rotating towards the direction of pulling out a safety belt, the winding drum is rotatably arranged on the frame, the pre-tensioning mechanism comprises a driving part and a pre-tensioning gear used for transmitting the power of the driving part, the pre-tensioning gear is used for being matched with the winding gear, the locking mechanism comprises a stopping piece, a driving piece and a clamping jaw, the stopping piece is rotatably arranged on the support, the clamping jaw is rotatably arranged on the frame, the driving piece is used for providing the driving force for clamping the clamping jaw with the locking gear, before the pretensioning mechanism is not activated, the stop tab stops the linkage to limit its rotation, and after the pretensioning mechanism is activated, the driving part drives the winding gear to rotate and simultaneously drives the stop piece to move so as to release the locking of the stop piece on the linkage piece.

Description

Seat belt retractor and vehicle

Technical Field

The disclosure relates to the technical field of vehicles, in particular to a winder for a safety belt and a vehicle.

Background

The existing safety belt winder has both a pyrotechnic pretensioning mechanism and a mechanical sensing locking mechanism. Under normal conditions, when the acceleration of pulling out the safety belt or the acceleration of the vehicle body is detected to exceed the acceleration set by the mechanical sensor, the mechanical sensing type locking mechanism locks the webbing winding device to prevent the webbing from being pulled out. When the vehicle has an emergency, if a forward collision occurs, the belt winding device is wound in the direction opposite to the pulling direction of the belt by the pyrotechnic pre-tensioning device, so that the looseness of the belt on the user is eliminated. The pyrotechnic pre-tensioning mechanism and the mechanical sensing type locking are relatively independent mechanically, and after the pyrotechnic pre-tensioning device is operated, the mesh belt winding device can be locked through the mechanical sensing type locking device, so that the mesh belt is prevented from being further pulled out after being pre-tensioned. However, the webbing take-up device may be pulled out by the load applied to the webbing by the occupant from the time the pyrotechnic pretensioner completes its operation until the mechanical sensor lock fully locks the webbing take-up device.

In order to solve the above problem, a locking mechanism is added to the retractor for the safety belt, which is called a second locking mechanism, the second locking mechanism is driven by a pre-tensioning mechanism, and after the pre-tensioning mechanism finishes working, the second locking mechanism can lock the locking gear, so that the problem that the safety belt is pulled out after the pre-tensioning mechanism works is solved. Chinese invention patent CN1672989 provides a technology for triggering the second locking mechanism by driving the clutch friction plate. Specifically, the friction plate rotates after being acted by the pyrotechnic pretensioning device, the locking lock is matched with the groove in the friction plate through two protrusions at the bottom to rotate together with the friction plate, the locking lock rotates away from an original locking position, the locking claw rotates from the unlocking position to the locking tooth on the outer side of the locking gear under the pushing of the spring until the locking gear is locked, and the rotation of the belt shaft in the pulling-out direction is locked through the connection of the locking gear and the belt shaft. However, there are two disadvantages in this solution: firstly, in order to realize the positioning of the locking lock in all directions, the volume of the locking lock must be set to be large enough, and the locking lock needs to rotate a certain angle to avoid the rotation of the locking claw, so that a large sector space needs to be set for the mechanism, and the winder for the safety belt is large; secondly, at a certain position, the friction sheet can cut off the convex part of the locking lock, and the cut convex part can fall into the positions of parts such as a winding shaft and the like, so that the normal work of related parts is easily influenced.

Disclosure of Invention

An object of the present disclosure is to provide a retractor for a seat belt, which can prevent the seat belt from being pulled out after a pretensioner mechanism is activated, and can effectively reduce the size of the retractor without generating a shear block during locking.

In order to achieve the above object, the present disclosure provides a retractor for a seat belt, including a frame to be mounted to a body of a vehicle, a support provided to the frame, a pretensioner mechanism provided to the support, a winding gear coupled to a spool for rotating the spool to wind the seat belt, a lock gear coupled to the spool and rotating integrally therewith, and a lock mechanism for preventing the spool from rotating in a direction to pull out the seat belt after the pretensioner mechanism is activated,

the winding drum is rotatably arranged on the frame, the pre-tensioning mechanism comprises a driving part and a pre-tensioning gear used for transmitting the power of the driving part, the pre-tensioning gear is used for being matched with the winding gear,

the locking mechanism comprises a stopping sheet, a driving piece and a clamping jaw, the stopping sheet is rotatably arranged on the support, the clamping jaw is rotatably arranged on the frame, the driving piece is used for providing driving force for clamping the clamping jaw with the locking gear,

before the pre-tensioning mechanism is not started, the stop piece stops the claw to limit the rotation of the claw, and after the pre-tensioning mechanism is started, the driving part drives the winding gear to rotate and simultaneously drives the stop piece to move so as to release the locking of the stop piece on the claw.

Optionally, the locking mechanism further includes a linkage member, the linkage member is rotatably disposed on the frame and is capable of driving the claw to be engaged with the locking gear, before the pre-tensioning mechanism is not started, the stopping piece stops the linkage member to limit the claw to rotate, and after the pre-tensioning mechanism is started, the driving portion drives the stopping piece to move to release the stopping piece to lock the linkage member.

Optionally, the driving part comprises a cylinder, a gas generator communicated with the inside of the cylinder, and a rack movably mounted on the cylinder along the axis of the cylinder, the rack is used for being meshed with the pretensioning gear, a trigger protrusion is formed on the stop piece, and after the pretensioning mechanism is started, the front end of the rack acts on the trigger protrusion in the moving process to enable the stop piece to move towards the direction of releasing the linkage piece.

Optionally, the backstop piece includes the backstop piece main part and with the L shape that backstop piece main part links to each other is rectangular, the L shape is rectangular including interconnect's first section and second section, the both ends of first section are connected respectively the second section with backstop piece main part, when the backstop piece is located initial position, backstop piece main part is located the upper surface of support and spacing the linkage, the rectangular opening of L shape is upwards, the second section is trigger protruding.

Optionally, the periphery of the stop sheet main body has a first side surface, a second side surface, a third side surface and a fourth side surface which are connected in sequence, the first side surface is opposite to the third side surface, the second side surface is opposite to the fourth side surface, the first section is arranged at the joint of the second side surface and the third side surface and extends towards the direction far away from the first side surface, an annular bulge surrounding the pre-tightening gear mounting hole is formed in the middle of the support, a first sliding groove and a second sliding groove which extend along the circumferential direction of the annular bulge and are mutually communicated are arranged on the upper surface of the support, the first sliding groove has a first radial limiting surface and a second radial limiting surface which are opposite, when the stop sheet is in the initial position, the stop sheet main body is located in the first sliding groove, the L-shaped strip is at least partially located in the second sliding groove, and the first side surface is limited on the first radial limiting surface, the second side surface is limited on the outer wall of the annular bulge, the fourth side surface stops the linkage piece, the rack drives the L-shaped strip to move in the second sliding groove when moving forwards, the stop sheet main body rotates towards the second radial limiting surface, the stop sheet is provided with a second position, and the second radial limiting surface stops the third side surface at the second position.

Optionally, when the stop piece is located at the initial position, a bottom wall of a distal end of the L-shaped strip abuts against the bottom wall of the second chute.

Optionally, a first avoidance groove is formed in the bottom wall of the second sliding groove and used for avoiding the second section when the rack is bent.

Optionally, the driving portion includes a cylinder, a gas generator communicated with the inside of the cylinder, and a rack movably mounted on the cylinder along an axis of the cylinder, the rack is configured to engage with the pre-tightening gear, the driving portion further includes a friction plate, the friction plate is connected to the pre-tightening gear, a trigger protrusion is formed on the stopper plate, and the friction plate acts on the trigger protrusion during rotation to enable the stopper plate to move in a direction of releasing the linkage.

Optionally, a radially extending gap is formed in an outer edge of the friction plate, and when the stop piece is located at the initial position, the trigger protrusion is inserted into the gap.

Optionally, the gap is a plurality of gaps and is circumferentially arranged at intervals on the friction plate.

Optionally, the backstop piece includes the backstop piece main part and with the L shape that backstop piece main part links to each other is rectangular, the L shape is rectangular including interconnect's first section and second section, the both ends of first section are connected respectively the second section with the backstop piece main part, works as when the backstop piece is located initial position, the backstop piece main part is located the upper surface of support and spacing the linkage, the rectangular opening orientation of L shape the friction disc, the second section is trigger protruding.

Optionally, the periphery of the stop sheet main body has a first side surface, a second side surface, a third side surface and a fourth side surface which are connected in sequence, the first side surface is opposite to the third side surface, the second side surface is opposite to the fourth side surface, the first section is arranged at the joint of the second side surface and the third side surface and extends towards the direction far away from the first side surface, an annular bulge surrounding the pre-tightening gear mounting hole is formed in the middle of the support, a first sliding groove and a second sliding groove which extend along the circumferential direction of the annular bulge and are communicated with each other are arranged on the upper surface of the support, the first sliding groove has a first radial limiting surface and a second radial limiting surface which are opposite to each other, when the stop sheet is in the initial position, the stop sheet main body is located in the first sliding groove, the L-shaped strip is at least partially located in the second sliding groove, and the first side surface is limited on the first radial limiting surface, the second side surface is limited on the outer wall of the annular protrusion, the fourth side surface stops blocking the linkage piece, the L-shaped strip is driven to move in the second sliding groove when the friction plate rotates, the stop piece body is made to rotate towards the second radial limiting surface, the stop piece is provided with a second position, and the second radial limiting surface stops the third side surface at the second position.

Optionally, when the stop piece is in the initial position, a bottom wall of a distal end of the L-shaped strip abuts against the second chute side wall.

Optionally, a second avoiding groove is formed in a side wall of the second sliding groove, and is used for avoiding the L-shaped strip when the friction plate is bent at the second section.

Optionally, the winder for the safety belt further comprises a pre-tightening cover plate, the stop piece is arranged between the support and the pre-tightening cover plate, a positioning protrusion is arranged on the upper surface of the stop piece, a positioning groove matched with the positioning protrusion is arranged at a position corresponding to the pre-tightening cover plate, and the pre-tightening cover plate is configured to be capable of avoiding the stop piece from moving in the vertical direction.

Optionally, the linkage piece and the jaw are arranged on the frame through the same rotating shaft, the driving piece is an elastic piece, two ends of the elastic piece are respectively connected to the frame and the linkage piece to provide elastic force for driving the linkage piece to rotate towards the locking gear, the linkage piece is located above the jaw and is provided with a protruding portion extending downwards, and the linkage piece drives the jaw to be close to the locking gear through the protruding portion.

Optionally, before the pretensioning mechanism is not activated, the power transmission between the pretensioning gear and the winding gear is disconnected, and the webbing retractor further includes a clutch mechanism for connecting the power transmission between the pretensioning gear and the winding gear.

Optionally, the clutch mechanism includes the pre-tightening gear, the winding gear, the support and the roller, the winding gear is disposed on the support, the pre-tightening gear is disposed through the support and coaxially disposed on the inner side of the winding gear, the roller is movably supported on the support and located between the winding gear and the pre-tightening gear, before the pre-tightening mechanism is not started, the roller does not transmit power of the pre-tightening gear, and after the pre-tightening mechanism is started, the pre-tightening gear rotates to drive the roller to rotate around the axis of the pre-tightening gear and approach to the winding gear, so that the roller is dynamically connected with the pre-tightening gear and the winding gear, and the winding gear is driven to rotate.

Optionally, the surface of the roller is formed with external gear hobbing, and the inner peripheral wall of the winding gear is formed with internal gear hobbing matched with the external gear hobbing.

Optionally, an arc-shaped tooth groove is formed between two adjacent external teeth of the pre-tightening gear, and the roller is partially located in the arc-shaped tooth groove.

Optionally, the roller is multiple and the rollers are arranged around the axis of the pre-tightening gear at intervals.

Optionally, the pre-tightening gear and/or the roller is connected to the support through a connecting piece, and when the pre-tightening mechanism is started, the pre-tightening gear and/or the roller shears the connecting piece.

Optionally, one end of the winding gear, which is far away from the support, is closed, and a containing cavity for containing the shearing block of the connecting sheet is defined by the support, the winding gear and the pre-tightening gear.

According to another aspect of the present disclosure, there is provided a vehicle including the webbing retractor described above.

Through the technical scheme, when the pre-tensioning mechanism is started, the driving part of the pre-tensioning mechanism drives the pre-tensioning gear to rotate, and the pre-tensioning gear drives the winding gear to drive the winding drum to wind the safety belt. Meanwhile, the stop piece rotates under the action of the pre-tensioning mechanism, and after the stop piece rotates to a certain position, the claw can be unlocked. The jack catch rotates towards the winding gear under the effect of the driving piece, so that the jack catch is timely clamped with the locking gear in a one-way mode, the safety belt is timely locked in a one-way mode, the safety belt can be prevented from being pulled out after the pretensioning process is finished, and the safety of the retractor is improved.

In this disclosure, the backstop piece can be set to the lamellar structure, can effectively reduce the volume of backstop piece, compares in the structure of stop lock in prior art, and its volume can reduce more than one time, has played effective compression space and has made compact structure's effect, is favorable to the miniaturization and the lightweight of winder. In addition, a convex connecting structure is omitted on the stop sheet, and a shearing block is not generated due to the fact that the convex is not sheared in the locking process, so that the shearing block is prevented from interfering the normal work of the winder after being sheared.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is an exploded view illustrating a structure of a retractor for a seat belt according to an embodiment of the present disclosure;

FIG. 2 is a schematic top view of an assembly of parts of a retractor for a seat belt according to a first embodiment of the present disclosure, with a rack of a pretensioner mechanism in an initial position;

FIG. 3 is a top view of the assembly of the components of the retractor for a seat belt according to the first embodiment of the present disclosure, wherein the rack of the pretensioning mechanism is just in contact with the stop tab;

FIG. 4 is a schematic top view of an assembly of parts of a retractor for a seat belt according to a first embodiment of the present disclosure, wherein the rack of the pretensioning mechanism bends the stop tab;

FIG. 5 is a top view of the assembled components of the seat belt retractor of FIG. 2 with the seat, linkage, etc. removed;

FIG. 6 is a schematic perspective view of a mount according to a first embodiment of the present disclosure;

fig. 7 is a schematic perspective view of a support with a stopping sheet mounted thereon according to a first embodiment of the present disclosure, wherein the stopping sheet is in a deformed state bent by a rack;

fig. 8 is a schematic structural view of a blocking sheet according to a first embodiment of the present disclosure;

fig. 9 is a schematic top view of an assembled configuration of parts of a retractor for a seat belt according to a second embodiment of the present disclosure, with a stop tab in an initial position;

fig. 10 is an exploded view of a part of a retractor for a seat belt according to a second embodiment of the disclosure, in which a support, a friction plate and a stopper plate are shown;

FIG. 11 is a schematic perspective view of a bracket with a stop piece mounted thereon according to a second embodiment of the present disclosure, wherein the stop piece is located at a second position and the L-shaped strip is located in a second avoiding groove;

FIG. 12 is a schematic view of a stopper piece according to a second embodiment of the present disclosure;

FIG. 13 is an exploded view of an assembled configuration of a linkage and pin according to one embodiment of the present disclosure;

FIG. 14 is a sectional view of the components of a wind gear, a pretensioning gear and a support according to an embodiment of the present disclosure assembled from a bottom perspective;

FIG. 15 is a schematic assembly view from above of components such as a wind-up gear, a pre-load gear, and a lock gear according to an embodiment of the present disclosure;

FIG. 16 is a schematic assembly diagram of a top view of components such as a pre-tightening gear and a support according to an embodiment of the present disclosure;

FIG. 17 is a bottom view assembly of the preloaded gear and carrier shown with rollers and first connecting tabs according to one embodiment of the present disclosure;

FIG. 18 is a perspective view of a support base according to an embodiment of the present disclosure, showing a roller, a first connecting tab and a second connecting tab;

FIG. 19 is a schematic perspective view of a roller according to one embodiment of the present disclosure;

fig. 20 is a schematic perspective view of a preloaded gear according to an embodiment of the present disclosure.

Description of the reference numerals

10-a frame; 11-the upper surface of the frame; 12-reel mounting holes; 21-a reel; 22-a locking gear; 23-a winding gear; 231-inner gear hobbing; 24-a winding shaft; 31-a drive section; 311-cylinder; 312-a gas generator; 313-a rack; 314-a sealing ring; 32-pre-tightening the gear; 321-a first gear; 322-a second gear; 323-arc tooth space; 33-friction plate; 331-a gap; 332-a snap-in part; 40-support; 41-pre-tightening gear mounting holes; 42-a first runner; 421-a first radial stop surface; 422-a second radial limiting surface; 43-a second chute; 431-a second chute bottom wall; 432-a second chute side wall; 44-a first avoidance slot; 45-a second avoidance slot; 46-an annular boss; 47-annular concave; 51-stop sheet; 511-a stopper piece body; 512. 512' -L-shaped strip; 513. 513' -a first section; 514. 514' -a second section; 515-a first side; 516-a second side; 517-third side; 518-fourth side; 519-positioning a projection; 52-a linkage; 521-a stopper piece mating surface; 522-a protrusion; 523-Driving member connection point; 53-claws; 54-a drive member; 55-a connecting member; 56-a cage; 57-pins; 60-pre-tightening the cover plate; 70-a roller; 71-external hobbing; 81-a first connecting piece; 82-a second connecting piece; 91-trigger plate.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, unless otherwise specified, the terms of orientation used such as "upper and lower" are defined with reference to the vertical direction shown in fig. 1, "front and rear" are defined with reference to the front and rear direction shown in fig. 2, and "inner and outer" refer to the inner and outer of the relevant component.

As shown in fig. 1 to 20, the present disclosure provides a retractor for a seat belt, which includes a frame 10 for being mounted to a body of a vehicle, a support 40 provided to the frame 10, a pretensioner mechanism provided to the support 40, a winding gear 23 coupled to a spool 21 for rotating the spool 21 to wind the seat belt, a lock gear 22 coupled to the spool 21 and rotating integrally, and a lock mechanism for preventing the spool 21 from rotating in a direction to pull out the seat belt after the pretensioner mechanism is activated. Alternatively, as shown in fig. 1, the winding gear 23 and the lock gear 22 may each be assembled integrally or integrally formed with the spool 21 so as to be capable of rotating integrally. As in the prior art, the winding shaft 24 may be connected to the spool 21 so as to be integrally rotatable, the spool 21 may be rotatably disposed in the spool mounting hole 12 of the frame 10, and the winding gear 23 and the lock gear 22 may be located outside the spool mounting hole 12.

The winding drum 21 is rotatably disposed on the frame 10, the pre-tightening mechanism includes a driving portion 31 and a pre-tightening gear 32 for transmitting power of the driving portion 31, the pre-tightening gear 32 is used for cooperating with the winding gear 23, the locking mechanism includes a stopping piece 51, a driving member 54 and a claw 53, the stopping piece 51 is rotatably disposed on the support 40, the claw 53 is rotatably disposed on the frame 10, and the driving member 54 is used for providing a driving force for engaging the claw 53 with the locking gear 22. Before the pretensioner mechanism is not activated, the stopper piece 51 stops the pawl 53 to restrict its rotation, and after the pretensioner mechanism is activated, the drive section 31 drives the movement of the stopper piece 51 to release the locking of the stopper piece 51 to the pawl 53 while driving the winding gear 23 to rotate.

In the retractor for a seat belt provided by the present disclosure, when the vehicle is in a normal state and the seat belt needs to be retracted, the trigger plate 91 is directly engaged with the winding shaft 24 (both of which use a gear transmission) to drive the winding drum 21 to retract the seat belt. The pretensioning mechanism is not activated and the locking of the vehicle seat belt is locked by a mechanical sensor locking mechanism of the belt retractor itself. When the pretensioning mechanism is started, the driving part 31 of the pretensioning mechanism drives the pretensioning gear 32 to rotate, and the pretensioning gear 32 drives the winding gear 23 along with the pretensioning gear to drive the winding drum 21 to wind up the safety belt. Meanwhile, the stop piece 51 rotates under the action of the pre-tensioning mechanism, and after the stop piece 51 rotates to a certain position, the claw 53 can be unlocked. Under the action of the driving piece 54, the claw 53 rotates towards the winding gear 23, so that the claw 53 is in one-way clamping with the locking gear 22 in time, the safety belt is in one-way locking in time, the safety belt can be prevented from being pulled out after the pretensioning process is finished, and the safety of the retractor is improved.

In this disclosure, the stop piece 51 can be set to a sheet structure, which can effectively reduce the volume of the stop piece 51, and compared with the structure of the stop lock in the prior art, the volume of the stop piece can be reduced by more than one time, so as to play an effect of effectively compressing the space to make the structure compact, and be beneficial to the miniaturization and the light weight of the winder. In addition, a convex connecting structure is omitted on the stop piece 51, so that a shearing block is not generated due to shearing of a convex in the locking process, and the shearing block is prevented from interfering with the normal operation of the winder after being sheared.

The stop plate 51 can be rotated by various structures such as the rack 313, the friction plate 33 and the like in the present disclosure, so that the design diversity and variability are improved, and the specific driving process can be described below.

It is understood that in the present disclosure, the stopper piece 51 may directly contact the stopping jaw 53, or may stop the jaw through other intermediate members. In one embodiment of the present disclosure, as shown in fig. 1 and 2, the locking mechanism further includes a link 52, the link 52 is rotatably disposed on the frame 10 and can drive the pawl 53 to engage with the locking gear 22, before the pre-tensioning mechanism is not activated, the stop piece 51 stops the link 52 to limit the rotation of the pawl 53, and after the pre-tensioning mechanism is activated, the driving portion 31 drives the stop piece 51 to move to release the locking of the stop piece 51 on the link 52. In this way, the pawl 53 can also be used in cooperation with a mechanical sensing type locking mechanism in a normal state of the vehicle, that is, two sets of locking mechanisms can share one pawl, so that the number of parts can be reduced, and the miniaturization and the light weight of the winder for the safety belt are facilitated.

The drive section 31 of the pretensioning mechanism of the present disclosure can be of any suitable construction. In one embodiment of the present disclosure, as shown in fig. 1 and 2, the driving portion 31 may include a cylinder 311, a gas generator 312 communicated with the inside of the cylinder 311, and a rack 313 movably mounted to the cylinder 311 along an axis of the cylinder 311, the rack 313 being configured to engage with the pre-tightening gear 32, the stop piece 51 having a trigger protrusion formed thereon, and after the pre-tightening mechanism is activated, a front end of the rack 313 acts on the trigger protrusion during the movement to move the stop piece 51 in a direction to release the link 52, thereby unlocking the link 52. When the stop piece 51 directly limits the position of the claw 53, the linkage can be unlocked.

Specifically, when an emergency occurs, the gas generator 312 is ignited, generates a large amount of gas and is sealed in the cylinder 311, so as to form a large pressure, and the rack 313 is pushed to move forward along the axial direction of the cylinder 311, so as to drive the pre-tightening gear 32 to rotate, and further drive the winding gear 23 to rotate, so as to realize the winding of the safety belt. Meanwhile, when the front end of the rack 313 moves, the trigger protrusion drives the stop piece 51 to rotate, so that the link 52 is unlocked, and the claw 53 can rotate to a position which is unidirectionally locked with the locking gear 22 in time, and the reel 21 is prevented from rotating towards the direction in which the safety belt is pulled out.

In the first embodiment of the present disclosure, the specific structure and shape of the stopper piece 51 are not limited. As shown in fig. 2 and 8, the stopper piece 51 may include a stopper piece main body 511 and an L-shaped strip 512 connected to the stopper piece main body 511, the L-shaped strip 512 includes a first section 513 and a second section 514 connected to each other, both ends of the first section 513 are respectively connected to the second section 514 and the stopper piece main body 511, when the stopper piece 51 is located at the initial position, the stopper piece main body 511 is located on the upper surface of the support 40 and limits the linkage piece 52, the opening of the L-shaped strip 512 is upward (i.e., in a direction away from the upper surface of the support 40), i.e., the second section 514 of the L-shaped strip 512 is arranged in an up-down direction, and the second section 514 is a trigger protrusion. Thus, during the forward movement of the rack 313, it can contact the second section 514 (trigger protrusion) arranged upward and bring the stop piece 51 to move on the support 40.

Specifically, as shown in fig. 8, the periphery of the stopper sheet main body 511 has a first side 515, a second side 516, a third side 517, and a fourth side 518 connected in this order, the first side 515 is opposite to the third side 517, the second side 516 is opposite to the fourth side 518, and the first segment 513 is provided at a joint portion of the second side 516 and the third side 517 and extends in a direction away from the first side 515. An annular bulge surrounding the pre-tightening gear mounting hole 41 is formed in the middle of the support 40, a first sliding groove 42 and a second sliding groove 43 which extend along the circumferential direction of the annular bulge and are communicated with each other are formed in the upper surface of the support 40, and the first sliding groove 42 is provided with a first radial limiting surface 421 and a second radial limiting surface 422 which are opposite to each other. When the stop piece 51 is in the initial position, the stop piece main body 511 is located in the first sliding groove 42, the L-shaped strip 512 is at least partially located in the second sliding groove 43, the first side 515 is limited on the first radial limiting surface 421, the second side 516 is limited on the outer wall of the annular protrusion, and the fourth side 518 stops the link piece 52. In addition, the stop piece 51 has a second position in which the second radial stop surface 422 stops the third side 517 to hold the stop piece 51 in a specific position on the support 40. In this way, in the initial position, the stop tab 51 is clamped between the annular projection of the support 40 and the linkage 52 and can remain fixed to achieve a reliable stop of the linkage 52.

When the rack 313 moves forward, the L-shaped strip 512 is driven to move in the second sliding groove 43, the second sliding groove 43 plays a guiding role, and the stopper main body 511 rotates in the first sliding groove 42 towards the second radial limiting surface 422, so that the linkage 52 can be unlocked after the stopper main body 511 rotates to a certain angle. The first and

second slide grooves

42 and 43 are provided to guide a path along which the stopper piece 51 moves, so that the stopper piece 51 moves smoothly. The stopper piece 51 provided by the embodiment has a simple structure, and can reliably lock the link 52 at the initial position and easily unlock the link 52 under the action of the rack 313 by matching with the first sliding groove 42 and the second sliding groove 43 on the support 40.

In order to avoid the second section 514 of the stopper piece 51 from being greatly deformed by the impact of the rack bar 313 when contacting the front end of the rack bar 313 and not being separated or not being separated from the initial position in time. In the first embodiment of the present disclosure, as shown in fig. 2, when the stop piece 51 is in the initial position, the bottom wall of the distal end of the L-shaped strip 512 abuts on the second chute bottom wall 431. Thus, when the rack 313 strikes the upper end of the second segment 514, the L-shaped bar 512 can move along the second runner 43 due to the supporting action of the second runner bottom wall 431, and thus the second segment 514 is less likely to be deformed. Until the stopping sheet 51 is located at the second position, the third side 517 of the stopping sheet main body 511 stops on the second radial limiting surface 422, at this time, the stopping sheet 51 cannot rotate any more, the second section 514 continues to be impacted by the rack 313, and at this time, the second section 514 is bent under the action of the rack 313.

It should be noted that the term "distal end of the L-shaped strip" as used herein refers to an end of the L-shaped strip 512 away from the stopper piece body 511.

Further, as shown in fig. 2, 6 and 7, a first avoiding groove 44 is formed in a bottom wall of the second sliding groove 43 to avoid the second section 514 when the rack 313 bends the second section 514. Thus, after the stop piece 51 is moved to the second position, when the rack 313 continues to act on the second section 514, the second section 514 can be bent and pressed into the first avoiding groove 44 to facilitate the continued travel of the rack 313.

In a second embodiment of the present disclosure, the power portion may include a cylinder 311, a gas generator 312 communicated with the inside of the cylinder 311, a rack 313 movably mounted on the cylinder 311 along an axis of the cylinder 311, the rack 313 being configured to engage with the pre-tightening gear 32, the driving portion 31 further includes a friction plate 33, the friction plate 33 is connected to the pre-tightening gear 32, optionally, as shown in fig. 9 and 10, the friction plate 33 may be clamped on an outer circumferential wall of the pre-tightening gear 32 by a clamping portion 332, a triggering protrusion is formed on the stopper plate 51, and the friction plate 33 acts on the triggering protrusion during rotation to move the stopper plate 51 toward a direction of releasing the link 52, so as to unlock the link 52.

Specifically, when an emergency occurs, the gas generator 312 detonates to generate a large amount of gas and is sealed in the cylinder 311, so as to form a large pressure, and the rack 313 is pushed to move forward along the axial direction of the cylinder 311, so as to drive the pre-tightening gear 32 to rotate, and further drive the winding gear 23 to rotate to realize the winding of the safety belt. At the same time, the pre-tightening gear 32 drives the friction plate 33 to rotate and drives the stop piece 51 to rotate through the trigger protrusion, so that the linkage piece 52 is unlocked, and the claw 53 can rotate to a position which is locked with the locking gear 22 in a one-way mode in time.

As shown in fig. 9 and 10, a slit 331 extending in the radial direction is formed on the outer edge of the friction plate 33, and when the stopper plate 51 is located at the initial position, the trigger protrusion is inserted into the slit 331. Thus, when the friction plate 33 rotates, the trigger protrusion is driven to rotate, and the structure is simple and the transmission is reliable. In other embodiments, the upper surface of the friction plate 33 may be formed with a convex pillar extending upward, and the convex pillar drives the trigger protrusion to rotate.

Further, as shown in fig. 10, the notches 331 may be a plurality of friction plates 33 arranged at intervals in the circumferential direction, so that the friction plates 33 can act on the stopper piece 51 by rotating a small angle, and the stopper piece 51 can be released from unlocking the link member 52, so that the claw 53 can be engaged with the lock gear 22 in time.

Also, in the second embodiment of the present disclosure, the specific structure and shape of the stopper piece 51 are not limited. As shown in fig. 9 and 12, the stopper piece 51 includes a stopper piece main body 511 and an L-shaped strip 512 'connected to the stopper piece main body 511, the L-shaped strip 512' includes a first section 513 'and a second section 514' connected to each other, and both ends of the first section 513 'are connected to the second section 514' and the stopper piece main body 511, respectively. When the stopper piece 51 is in the initial position, the stopper piece main body 511 is located on the upper surface of the holder 40 and restrains the link piece 52, the L-shaped strip 512 'opens toward the friction plate 33, i.e., toward the rotational axis of the friction plate 33, and the second section 514' is a trigger projection. Thus, when the friction plate 33 rotates in the circumferential direction, the retaining plate 51 is moved on the support 40 by the notch 331 engaging with the second segment 514' (trigger protrusion) arranged along the radial direction of the friction plate 33.

Specifically, in the second embodiment of the present disclosure, as shown in fig. 12, the periphery of the stopper plate main body 511 has a first side 515, a second side 516, a third side 517, and a fourth side 518 connected in sequence, the first side 515 is opposite to the third side 517, the second side 516 is opposite to the fourth side 518, a first segment 513' is disposed at a joint portion of the second side 516 and the third side 517 and extends in a direction away from the first side 515, an annular protrusion surrounding the preload wheel mounting hole is formed at a middle portion of the support 40, a first sliding groove 42 and a second sliding groove 43 extending in a circumferential direction along a side wall of the annular protrusion and communicating with each other are disposed on an upper surface of the support 40, and the first sliding groove 42 has a first radial limiting surface 421 and a second radial limiting surface 422 which are opposite to each other. When the stopping sheet 51 is in the initial position, the stopping sheet main body 511 is located in the first sliding groove 42, the L-shaped strip 512' is at least partially located in the second sliding groove 43, the first side surface 515 is limited on the first radial limiting surface 421, the second side surface 516 is limited on the outer wall of the annular protrusion, and the fourth side surface 518 stops the link member 52. When the friction plate 33 rotates, the L-shaped bar 512' is driven to move in the second sliding slot 43, and the stopper plate main body 511 rotates toward the second radial direction limiting surface 422. In addition, the stop piece 51 has a second position in which the second radial stop surface 422 stops the third side 517 to hold the stop piece 51 in a specific position on the support 40. In this way, in the initial position, the stop tab 51 is clamped between the annular projection of the support 40 and the linkage 52 and can remain fixed to achieve a reliable stop of the linkage 52.

When the friction plate 33 rotates, the L-shaped strip 512' is driven to move in the second sliding slot 43, and the stopper plate main body 511 rotates in the first sliding slot 42 toward the second radial limiting surface 422, so that the linkage member 52 can be unlocked after the stopper plate main body 511 rotates to a certain angle. The first and

second slide grooves

42 and 43 are provided to guide a path along which the stopper piece 51 moves, so that the stopper piece 51 moves smoothly. The stop plate 51 provided by the embodiment has a simple structure, and can reliably lock the linkage member 52 at the initial position and easily unlock the linkage member 52 under the action of the friction plate 33 by matching with the first sliding groove 42 and the second sliding groove 43 on the support 40.

In order to prevent the second segment 514' of the stopper piece 51 from being greatly deformed by the friction plate 33 when contacting the notch 331 of the friction plate 33, and thus cannot be separated or cannot be separated from the initial position in time. In the second embodiment of the present disclosure, as shown in fig. 9, when the stopper piece 51 is located at the initial position, the bottom wall of the distal end of the L-shaped strip 512 '(i.e., the bottom wall 5131' of the first segment shown in fig. 12) abuts against the second chute side wall 432. Thus, when the friction plate 33 impacts the second step 514 ', the second step 514 ' is not easily deformed due to the supporting function of the second chute side wall 432 and the movement of the L-shaped strip 512 ' along the second chute 43. Until the stopping sheet 51 is located at the second position, the third side 517 of the stopping sheet main body 511 stops on the second radial limiting surface 422, at this time, the stopping sheet 51 cannot rotate any more, and the second segment 514 'continues to be impacted by the friction plate 33, at this time, the second segment 514' will be bent under the action of the friction plate 33.

Similarly, the "distal end of the L-shaped strip" refers to the end of the L-shaped strip 512' that is distal from the stopper piece body 511.

Further, as shown in fig. 10 and 11, a second avoiding groove 45 is formed on a side wall of the second sliding groove 43 to avoid the L-shaped long strip 512 when the friction plate 33 bends the second section 514'. Thus, when the friction plate 33 continues to rotate to act on the second segment 514 'after the stop piece 51 moves to the second position, the second segment 514' can be bent and pressed into the second avoiding groove 45 to facilitate the continuous rotation of the friction plate 33, so that the rotation of the winding gear 23 is not affected.

The material of the stop sheet 51 is not limited in the present disclosure, and in one embodiment, the stop sheet 51 may be a metal elastic sheet to be deformable while having a certain strength, so that the second section 514 of the stop sheet 51 can be deformed under the extrusion of the rack 313 or the friction plate 33 to avoid affecting the continuous movement of the rack 313 and the friction plate 33. In other embodiments, it may be a deformable rubber member or the like.

As shown in fig. 1, the retractor for a seat belt further includes a pre-tightening cover plate 60, the stopper piece 51 may be disposed between the support 40 and the pre-tightening cover plate 60, a positioning protrusion 519 is disposed on an upper surface of the stopper piece 51, a positioning groove (not shown in the figure) adapted to the positioning protrusion 519 is disposed at a position corresponding to the pre-tightening cover plate 60, and the pre-tightening cover plate 60 is configured to prevent the stopper piece 51 from moving in the vertical direction. Specifically, the stop tab 51 may be configured as a transition or slight interference fit between the seat 40 and the pre-tensioned cover plate 60. Because the upper surface of the support 40 of the stopping sheet 51 is provided with the annular bulge, the first radial limiting surface 421, the second radial limiting surface 422 and the limiting of the linkage piece 52, the stopping sheet 51 realizes basic positioning and fastening in the up-down direction and the horizontal direction, and cannot shake, so that abnormal sound cannot be generated.

As shown in fig. 1, 2 and 9, the link 52 and the pawl 53 may be disposed on the frame 10 through the same rotation shaft, the driving member 54 may be an elastic member, two ends of the elastic member are respectively connected to the frame 10 and the link 52 to provide an elastic force for driving the link 52 to rotate toward the locking gear 22, the link 52 is located above the pawl 53, the link 52 has a protrusion 522 extending downward, and the link 52 drives the pawl 53 to approach the locking gear 22 through the protrusion 522. In this way, when the stopper piece 51 releases the locking of the link 52, both the link 52 and the pawl 53 rotate around the rotation shaft in the direction toward the lock gear 22 by the elastic member, so that the pawl 53 engages with the lock gear 22 to realize unidirectional locking. Alternatively, the linkage 52 can be covered above the jaws 53, so as to save the arrangement space on the surface of the support 40, and the linkage 52 and the jaws 53 are arranged to rotate coaxially, so that the rotation synchronism of the linkage 52 and the jaws 53 is facilitated, and the jaws 53 can rotate to the one-way locking position under the action of the linkage 52.

Wherein, as shown in fig. 13, the rotating shaft may be a pin 57 to rotatably dispose the link 52 and the jaw 53 on the frame 10. Further, the locking mechanism may further include a connecting member 55 and a holder 56, the connecting member 55 is connected to the claw 53, the connecting member 55, the claw 53 and the link 52 are all mounted on the upper surface 11 of the frame through the holder 56, and the connecting member 55 is configured to cooperate with a mechanical locking mechanism of the vehicle to drive the claw 53 to be engaged with the locking gear 22.

As shown in fig. 13, the protrusion 522 and the driver connecting point 523 of the link 52 are respectively located on both sides of the pin 57, and form a lever structure with the pin 57 as a fulcrum, and the link 52 has a stopper piece engagement surface 51.

Here, the elastic member may be a spring plate or a spring. When the stop tab 51 is in the initial position, the spring or spring is in a compressed state. In addition, the driving member 54 may be an air bag which is compressed when the stopper piece 51 is at the initial position to provide a rotational force to the link member 52.

In the present disclosure, the webbing retractor further includes a clutch mechanism for connecting power transmission between the preload gear 32 and the take-up gear 23. When the vehicle is in a normal state, in order not to affect the normal withdrawal and retraction of the seat belt in such a state, the clutch mechanism is in a disengaged state, and no power transmission is transmitted between the pretensioner gear 32 and the winding gear 23, that is, the power transmission between the pretensioner gear 32 and the winding gear 23 is disconnected before the pretensioner mechanism is not activated. When the vehicle is in an emergency, the clutch mechanism is engaged, and after the retractor receives a signal for starting the pre-tensioning mechanism, the gas generator 312 is ignited, so that the rack 313 is pushed to move, the rack 313 then drives the pre-tensioning gear 32 to rotate, and the pre-tensioning gear 32 drives the winding gear 23 to rotate through the clutch mechanism, so that the winding drum 21 is driven to wind the safety belt.

In the present disclosure, the clutch mechanism may have any suitable structure as long as it can achieve communication or disconnection of power transmission between the winding gear 23 and the preload gear 32. Optionally, since the clutch mechanism in the present disclosure is mainly used for the retraction process of the safety belt, the clutch mechanism may be a one-way clutch mechanism.

The clutch mechanism may be a friction ring used to transmit power between the pre-tightening gear 32 and the winding gear 23 in the prior art. In one embodiment. As shown in fig. 14, 16 and 17, the clutch mechanism may include a pre-tightening gear 32, a winding gear 23, a roller 70 and the support 40, the pre-tightening gear 32 is used for transmitting the power of the driving portion 31, the winding gear 23 is used for driving the winding drum 21 to rotate to wind the seat belt, the winding gear 23 is disposed on the support 40, the pre-tightening gear 32 is disposed through the support 40 and coaxially disposed inside the winding gear 23, and the roller 70 is movably supported on the support 40 and located between the winding gear 23 and the pre-tightening gear 32. Before the pretensioning mechanism is not activated, the roller 70 does not transmit power between the pretensioning gear 32 and the winding gear 23. Alternatively, as shown in fig. 16, the roller 70 is now spaced from both the pretensioning gear 32 and the winding gear 23. After the pretensioning mechanism is started, the pretensioning gear 32 rotates to drive the roller 70 to rotate around the axis of the pretensioning gear 32 and close to the winding gear 23, so that the roller 70 is in power connection with the pretensioning gear 32 and the winding gear 23, thereby driving the winding gear 23 to rotate, and completing the transmission of motion and load in the direction of retracting the safety belt.

Compared with the scheme of adopting friction ring transmission in the prior art, the roller 70 is not easy to deform and slip, the stability and reliability of power transmission are higher, and the working reliability of the clutch mechanism is high.

Alternatively, the number of rollers 70 may be plural and plural rollers may be arranged at intervals around the axis of the pre-tightening gear 32 to improve the smoothness and reliability of the transmission by increasing the number of rollers 70.

In order to further improve the reliability of the roller 70 in power transmission, as shown in fig. 18 and 19, in one embodiment of the present disclosure, an outer gear 71 is formed on the surface of the roller 70, and correspondingly, an inner gear 231 adapted to the outer gear 71 is formed on the inner circumferential wall of the winding gear 23. Thus, the friction coefficient between the roller 70 and the winding gear 23 can be increased, the friction connection effect can be improved, and the transmission reliability is greatly improved.

The shape of the outer teeth 71 of the roller 70 is not limited in the present disclosure, and optionally, as shown in fig. 19, the roller 70 may be knurled to have the outer teeth 71 of a circular knurled teeth.

As shown in fig. 14 and 15, an arc-shaped tooth groove 323 is formed between two adjacent external teeth of the pre-tightening gear 32, and the roller 70 is partially located in the arc-shaped tooth groove 323, that is, the profile surface of the tooth groove of the pre-tightening gear 32 is an arc-shaped surface, so as to facilitate the movement of the driving roller 70. As shown in fig. 14, when the pre-tightening gear 32 rotates clockwise in the drawing of fig. 14, the roller 70 is easily rotated together, and the roller 70 is pressed to be close to the winding gear 23 located at the outer side, thereby rotating the winding gear 23. The provision of the arcuate gullets 323 facilitates the movement of the drive roller 70 in both radial and circumferential directions thereof.

In order to ensure that no power transmission takes place between the pretensioning gear 32 and the winding gear 23 before the pretensioning mechanism of the winder is not activated in the present disclosure, in one embodiment of the present disclosure the pretensioning gear 32 and/or the roller 70 may be connected to the support 40 by a web, the pretensioning gear 32 and/or the roller 70 shearing off the web when the pretensioning mechanism is activated. In this way, the web ensures that the pretensioning gear 32 and the roller 70 do not rotate before the pretensioning mechanism of the winder is not activated, so that the power transmission between the pretensioning gear 32 and the winding gear 23 is not communicated, and the normal winding and unwinding of the mounting tape in the normal state of the vehicle is not affected.

The pre-tightening gear 32 and the roller 70 may be fixed to the support 40 by connecting pieces, such as the first connecting piece 81 and the second connecting piece 82 shown in fig. 18, or one of the two may be fixed to the support 40 by connecting pieces, which is not limited by the present disclosure. In one embodiment, as shown in fig. 18, the pretensioning gear 32 and the roller 70 can be fixed to the support 40 by a first connecting tab 81 and a second connecting tab 82, respectively, to ensure that neither the pretensioning gear 32 nor the roller 70 rotate before the pretensioning mechanism is activated.

In another embodiment of the present disclosure, as shown in fig. 17, the pre-tightening gear 32 is fixed to the support 40 by a first connecting piece 81, and no connecting piece is provided between the roller 70 and the support 40. In other embodiments, the roller 70 may be fixed to the support 40 only by the second connecting piece 82, and no connecting piece is provided between the pre-tightening gear 32 and the support 40.

As shown in fig. 1 and 14, an end of the winding gear 23 away from the support 40 is closed, and a receiving cavity for receiving the cutting block of the connecting pieces (the first connecting piece 81 and the second connecting piece 82) is defined among the support 40, the winding gear 23 and the pre-tightening gear 32. So that the cut pieces of the first connecting piece 81 and the second connecting piece 82 are confined in the accommodating cavities without affecting other parts.

The first connecting piece 81 and the second connecting piece 82 are not limited in material, and can be made of plastic connecting pieces, so that the cost is saved, or metal sheets and the like can be selected. In one embodiment, plastic tabs may be used to save cost.

Alternatively, in an embodiment of the present disclosure, as shown in fig. 16, 17 and 20, the pre-tightening gear 32 includes a first gear 321 and a second gear 322 arranged along an axial direction thereof, a pre-tightening wheel mounting hole 41 is provided on the support 40, the first gear 321 is disposed through the pre-tightening wheel mounting hole 41, the second gear 322 is located at a lower side of the support 40, the first gear 321 is configured to cooperate with the rack 313, and the second gear 322 is configured to cooperate with the winding gear 23 through the roller 70 in a transmission manner. And due to the special design of the pre-tightening gear 32, namely, the first gear 321 and the second gear 322 are respectively designed to be matched with the rack 313 and the winding gear 23, the first gear 321 and the second gear 322 can be designed with adaptive structures according to the matched objects. For example, in order to facilitate the second gear 322 to drive the roller 70 to move in the radial and circumferential directions, as shown in fig. 17, an arc-shaped tooth groove 323 is formed between two adjacent external teeth of the second gear 322, and the roller 70 is partially located in the arc-shaped tooth groove 323.

As shown in fig. 18, the second gear 322 is connected to the support 40 via the first connecting piece 81, and the second gear 322 shears the first connecting piece 81 when rotating.

As shown in fig. 18 and 19, in one embodiment of the present disclosure, a hollow annular flange is formed on a side wall of the lock gear 22, and an inner wall of the hollow annular flange has an inner gear hob 231 to configure a winding gear 23. That is, in the present disclosure, the lock gear 22 and the winding gear 23 are both provided at an end portion of the drum 21 and rotate integrally with the drum 21, and the lock gear 22 and the winding gear 23 are integrally connected, and a hollow annular flange on the lock gear 22 is the winding gear 23. The design can save the arrangement space and is beneficial to reducing the volume of the whole winder for the safety belt.

In addition, in the present disclosure, in order to facilitate the installation of the roller 70 and the winding gear 23, the holder 40 is provided with an annular recess 47 around which the preload wheel installation hole 41 is provided, and one end of the installation shaft 70 and one end of the winding gear are located in the annular recess 47. In this way, the housing cavity may be constructed by the bottom wall of the hollow annular flange, the side wall of the hollow annular flange, the bottom wall of the annular recess 47 and the second gear 322.

According to another aspect of the present disclosure, there is provided a vehicle including the webbing retractor described above mounted to a vehicle body by a frame 10, optionally attachable to the vehicle body by fastening bolts.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A retractor for a seat belt, comprising a frame (10) to be mounted to a body of a vehicle, a support (40) provided to the frame (10), a pretensioner mechanism provided to the support (40), a winding gear (23) connected to a spool (21) for rotating the spool (21) to wind up the seat belt, a lock gear (22) connected to the spool (21) and rotating integrally, and a lock mechanism for preventing the spool (21) from rotating in a direction to pull out the seat belt after the pretensioner mechanism is activated,

the winding drum (21) is rotatably arranged on the frame (10), the pre-tensioning mechanism comprises a driving part (31) and a pre-tensioning gear (32) used for transmitting the power of the driving part (31), the pre-tensioning gear (32) is used for being matched with the winding gear (23),

the locking mechanism comprises a stopping sheet (51), a driving piece (54) and a clamping jaw (53), the stopping sheet (51) is rotatably arranged on the support (40), the clamping jaw (53) is rotatably arranged on the frame (10), the driving piece (54) is used for providing driving force for clamping the clamping jaw (53) and the locking gear (22),

before the pre-tensioning mechanism is not started, the stop piece (51) stops the claw (53) to limit the rotation of the claw, and after the pre-tensioning mechanism is started, the driving part (31) drives the winding gear (23) to rotate and simultaneously drives the stop piece (51) to move so as to release the locking of the stop piece (51) on the claw (53);

the locking mechanism further comprises a linkage piece (52), the linkage piece (52) is rotatably arranged on the frame (10) and can drive the claw (53) to be clamped with the locking gear (22), the stop piece (51) stops the linkage piece (52) to limit the claw (53) to rotate before the pre-tensioning mechanism is not started, and the driving part (31) drives the stop piece (51) to move to release the locking of the stop piece (51) on the linkage piece (52) after the pre-tensioning mechanism is started;

the driving part (31) comprises a cylinder (311), a gas generator (312) communicated with the interior of the cylinder (311), and a rack (313) movably arranged on the cylinder (311) along the axis of the cylinder (311), wherein the rack (313) is used for being meshed with the pre-tightening gear (32), a trigger bulge is formed on the stop piece (51), and after the pre-tightening mechanism is started, the front end of the rack (313) acts on the trigger bulge in the moving process to enable the stop piece (51) to move towards the direction of releasing the linkage piece (52).

2. The retractor for a safety belt according to claim 1, wherein the stopper piece (51) includes a stopper piece main body (511) and an L-shaped strip (512) connected to the stopper piece main body (511), the L-shaped strip (512) includes a first section (513) and a second section (514) connected to each other, both ends of the first section (513) are connected to the second section (514) and the stopper piece main body (511), respectively, when the stopper piece (51) is located at an initial position, the stopper piece main body (511) is located on an upper surface of the support (40) and limits the linkage piece (52), an opening of the L-shaped strip (512) faces upward, and the second section (514) is the trigger protrusion.

3. The webbing retractor according to claim 2, wherein the stopper piece main body (511) has a peripheral edge having a first side surface (515), a second side surface (516), a third side surface (517), and a fourth side surface (518) which are connected in this order, the first side surface (515) is opposite to the third side surface (517), the second side surface (516) is opposite to the fourth side surface (518), the first segment (513) is provided at a junction of the second side surface (516) and the third side surface (517) and extends in a direction away from the first side surface (515), an annular protrusion (46) surrounding the pretensioned gear mounting hole (41) is formed at a middle portion of the holder (40), and a first slide groove (42) and a second slide groove (43) which extend in a circumferential direction of the annular protrusion (46) and communicate with each other are provided on an upper surface of the holder (40), the first sliding groove (42) is provided with a first radial limiting surface (421) and a second radial limiting surface (422) which are opposite, when the stopping sheet (51) is in an initial position, the stopping sheet main body (511) is positioned in the first sliding groove (42), the L-shaped strip (512) is at least partially positioned in the second sliding groove (43), the first side surface (515) is limited on the first radial limiting surface (421), the second side surface (516) is limited on the outer wall of the annular protrusion (46), the fourth side surface (518) stops the linkage piece (52), the L-shaped strip (512) is driven to move in the second sliding groove (43) when the rack (313) moves forwards, the stopping sheet main body (511) rotates towards the second radial limiting surface (422), the stopping sheet (51) is provided with a second position, and in the second position, the second radial limiting surface (422) stops the third side surface (517).

4. The webbing retractor of claim 3, wherein a bottom wall of a distal end of the L-shaped strip (512) abuts against the second chute bottom wall (431) when the stopper piece (51) is in the initial position.

5. The webbing retractor according to claim 3, wherein a bottom wall of the second slide groove (43) is formed with a first escape groove (44) for escaping the second section (514) when the rack (313) bends the second section (514).

6. The belt retractor according to claim 1, wherein the drive portion (31) includes a cylinder (311), a gas generator (312) communicating with an inside of the cylinder (311), and a rack (313) movably mounted to the cylinder (311) along an axis of the cylinder (311), the rack (313) being adapted to engage with the preload gear (32), the drive portion (31) further includes a friction plate (33), the friction plate (33) being connected to the preload gear (32), the stopper piece (51) having a trigger protrusion formed thereon, the friction plate (33) acting on the trigger protrusion during rotation to move the stopper piece (51) in a direction to release the link (52).

7. The webbing retractor of claim 6 wherein the outer edge of the friction plate (33) is formed with a radially extending slit (331), the trigger protrusion being inserted into the slit (331) when the stopper plate (51) is in the initial position.

8. The webbing retractor according to claim 7, wherein the slit (331) is plural and arranged at circumferential intervals in the friction plate (33).

9. The webbing retractor of claim 7, wherein the stopper piece (51) includes a stopper piece main body (511) and an L-shaped strip (512 ') connected to the stopper piece main body (511), the L-shaped strip (512') includes a first section (513 ') and a second section (514') connected to each other, both ends of the first section (513 ') are connected to the second section (514') and the stopper piece main body (511), respectively, the stopper piece main body (511) is located on an upper surface of the holder (40) and restrains the link piece (52) when the stopper piece (51) is located at an initial position, an opening of the L-shaped strip (512 ') faces the friction plate (33), and the second section (514') is the trigger projection.

10. The webbing retractor according to claim 9, wherein the stopper piece main body (511) has a peripheral edge having a first side surface (515), a second side surface (516), a third side surface (517), and a fourth side surface (518) which are connected in this order, the first side surface (515) is opposite to the third side surface (517), the second side surface (516) is opposite to the fourth side surface (518), the first segment (513') is provided at a junction of the second side surface (516) and the third side surface (517) and extends in a direction away from the first side surface (515), an annular protrusion (46) is formed in a middle portion of the holder (40) around the pretensioned gear mounting hole (41), and a first slide groove (42) and a second slide groove (43) which extend in a circumferential direction of the annular protrusion (46) and communicate with each other are provided on an upper surface of the holder (40), the first sliding groove (42) is provided with a first radial limiting surface (421) and a second radial limiting surface (422) which are opposite, when the stopping piece (51) is in an initial position, the stopping piece main body (511) is positioned in the first sliding groove (42), the L-shaped strip (512 ') is at least partially positioned in the second sliding groove (43), the first side surface (515) is limited on the first radial limiting surface (421), the second side surface (516) is limited on the outer wall of the annular bulge (46), the fourth side surface (518) stops the linkage piece (52), the L-shaped strip (512') is driven to move in the second sliding groove (43) when the friction plate (33) rotates, the stopping piece main body (511) rotates towards the second radial limiting surface (422), the stopping piece (51) is provided with a second position, and in the second position, the second radial limiting surface (422) stops the third side surface (517).

11. The webbing retractor of claim 10, wherein a bottom wall of a distal end of the L-shaped strip (512') abuts against the second chute side wall (432) when the stopper piece (51) is in the initial position.

12. The webbing retractor of claim 10, wherein a side wall of the second slide groove (43) is formed with a second escape groove (45) for escaping the L-shaped strip (512 ') when the friction plate (33) bends the second segment (514').

13. The retractor for a safety belt according to claim 1, further comprising a pre-tightening cover plate (60), wherein the stopper piece (51) is disposed between the support (40) and the pre-tightening cover plate (60), a positioning protrusion (519) is disposed on an upper surface of the stopper piece (51), a positioning groove adapted to the positioning protrusion (519) is disposed at a corresponding position of the pre-tightening cover plate (60), and the pre-tightening cover plate (60) is configured to prevent the stopper piece (51) from moving in an up-down direction.

14. The webbing retractor of claim 1, wherein the link member (52) and the pawl (53) are provided on the frame (10) through the same rotation shaft, the driving member (54) is an elastic member, both ends of the elastic member are respectively connected to the frame (10) and the link member (52) to provide an elastic force for urging the link member (52) to rotate in a direction toward the lock gear (22), the link member (52) is located above the pawl (53), the link member (52) has a protrusion (522) extending downward, and the link member (52) brings the pawl (53) close to the lock gear (22) through the protrusion (522).

15. The belt retractor according to any of claims 1 to 14, wherein the power transmission between the pretensioning gear (32) and the winding gear (23) is disconnected before the pretensioning mechanism is deactivated, the belt retractor further comprising a clutch mechanism for switching on the power transmission between the pretensioning gear (32) and the winding gear (23).

16. The retractor for a safety belt according to claim 15, wherein the clutch mechanism includes the preload gear (32), the winding gear (23), the support (40), and a roller (70), the winding gear (23) is disposed on the support (40), the preload gear (32) is disposed through the support (40) and coaxially disposed inside the winding gear (23), the roller (70) is movably supported on the support (40) and is located between the winding gear (23) and the preload gear (32),

before the pre-tightening mechanism is not started, the roller (70) does not transmit the power of the pre-tightening gear (32), and after the pre-tightening mechanism is started, the pre-tightening gear (32) rotates to drive the roller (70) to rotate around the axis of the pre-tightening gear (32) and approach the winding gear (23), so that the roller (70) is in power connection with the pre-tightening gear (32) and the winding gear (23) to drive the winding gear (23) to rotate.

17. The webbing retractor according to claim 16, wherein the roller (70) has an outer gear (71) formed on a surface thereof, and the winding gear (23) has an inner gear (231) formed on an inner peripheral wall thereof to be fitted to the outer gear (71).

18. The webbing retractor of claim 16, wherein an arc-shaped tooth groove (323) is formed between adjacent two outer teeth of the pretensioner gear (32), and the roller (70) is partially located in the arc-shaped tooth groove (323).

19. The webbing retractor of claim 16, wherein the roller (70) is plural and the plural rollers (70) are arranged at intervals around an axis of the pretensioned gear (32).

20. The belt retractor according to any of claims 16 to 19 wherein the pretensioning gear (32) and/or the roller (70) is connected to the support (40) by a web, the pretensioning gear (32) and/or the roller (70) shearing off the web when the pretensioning mechanism is activated.

21. The belt retractor according to claim 20 wherein the end of the winding gear (23) remote from the support (40) is closed, the support (40), the winding gear (23) and the pretensioning gear (32) enclosing a receiving chamber therebetween for receiving the shear block of the web.

22. A vehicle characterized in that it comprises a retractor for a safety belt according to any one of claims 1 to 21.