Waist pretensioner of safety belt

Abstract

The embodiment of the utility model provides a safety belt waist pre-tensioner which comprises a frame, a reel and a pre-tightening device, the reel is rotatably installed on the frame, the pre-tightening device is installed on the frame and matched with the reel, one end of a safety belt is inserted into a containing cavity of the reel through a quick-inserting end piece, and the other end of the safety belt is connected with the quick-inserting end piece. The quick-insertion end piece comprises a limiting hook and a first limiting part which are used for insertion, a clamping part and a second limiting part are formed in the containing cavity, the clamping part is matched with the limiting hook in the plane where the limiting hook is located, and the second limiting part is configured to be matched with the first limiting part in the rotating direction of the reel so as to further limit movement of the quick-insertion end piece. The clamping part and the second limiting part are arranged in the containing cavity of the reel, and when the quick-insertion end piece is inserted into the reel, the clamping part is matched with the limiting hook on the quick-insertion end piece, so that quick-insertion connection between the quick-insertion end piece and the reel is achieved, and the second limiting part is matched with the first limiting part on the quick-insertion end piece; separation between the quick-plug end piece and the reel can be avoided when the reel rotates.

Description

Technical Field

[0001] The present invention relates to the technical field of seat belts, and in particular to a seat belt lap pretensioner. Background Art

[0002] A lap pretensioner is a device used in vehicle safety systems. Its primary function is to quickly tighten the seatbelt webbing in the event of a collision, reducing the gap between the occupant and the belt. This effectively secures the occupant in the seat and reduces collision injuries. With the rapid advancement of safety technology, traditional pretensioner structures are complex, leading to the adoption of integrated quick-release mechanisms by major automakers. However, existing quick-release mechanisms generally only ensure lateral movement and fail to eliminate the risk of disengagement caused by the rotating reel, compromising driving safety. Summary of the Invention

[0003] In view of this, an embodiment of the present specification provides a seat belt lap pretensioner, which provides a snap-fitting portion and a second limiting portion in the accommodating cavity of the reel. When the quick-insert end piece is inserted into the reel, the snap-fitting portion cooperates with the limiting hook on the quick-insert end piece to achieve a quick-insert connection between the quick-insert end piece and the reel, which can prevent the quick-insert end piece from being pulled out. The second limiting portion cooperates with the first limiting portion on the quick-insert end piece to prevent the quick-insert end piece from being separated from the reel when the reel rotates.

[0004] The embodiments of this specification provide the following technical solutions: a seat belt lap pretensioner, comprising a frame, a reel, and a pretensioning device, wherein one end of the seat belt is fixed to the reel, the reel is rotatably mounted on the frame, the pretensioning device is mounted on the frame and cooperates with the reel, and when braking, the reel is driven to rotate relative to the frame to further reel the seat belt webbing onto the reel.

[0005] One end of the safety belt is inserted into the accommodating cavity of the reel through a quick-insert end piece, and the quick-insert end piece includes a limit hook and a first limit portion for insertion. A clamping portion and a second limit portion are formed in the accommodating cavity. The clamping portion is configured to cooperate with the limit hook in the plane where the limit hook is located to limit the movement of the quick-insert end piece in the direction away from the accommodating cavity. The second limit portion is configured to cooperate with the first limit portion in the rotation direction of the reel to further limit the movement of the quick-insert end piece.

[0006] Preferably, the quick-insert end piece also includes a main piece connected to the safety belt, the main piece and the limiting hook are arranged in the same plane, the first limiting part is arranged on the main piece, and is configured to cooperate with the second limiting part when the reel rotates.

[0007] Preferably, the first limiting portion includes two groups of limiting holes opened on the main piece, the main piece is provided with an insertion port for the webbing to pass through, the two groups of limiting holes are respectively arranged on both sides of the insertion port, and the second limiting portion includes a limiting block corresponding to the limiting hole, and the limiting block is configured to be at least partially embedded in the limiting hole when the reel rotates.

[0008] Preferably, an inner top wall of the limiting hole is formed with an inclined surface, and the size of the limiting hole gradually becomes smaller in a direction away from the limiting block, so that the limiting block can be easily embedded in the limiting hole.

[0009] Preferably, the reel includes an upper cylindrical portion and a lower cylindrical portion that cooperate with each other, the accommodating cavity is formed in the upper cylindrical portion, and a sliding groove for radially limiting the engaging portion is formed at the upper cylindrical portion and / or the lower cylindrical portion, so that the engaging portion moves along the axial direction of the reel, and a biasing member is provided in the accommodating cavity, and the biasing member always pushes the engaging portion to move in a direction close to the quick-insert end piece.

[0010] Preferably, the engaging portion includes two groups of limiting claws, which are respectively arranged on opposite sides of the limiting hook, and the opposite sides of the limiting hook respectively extend toward the direction close to the two groups of limiting claws to form grooves, and the two groups of limiting claws respectively extend toward the direction close to the limiting hook to form hook claws, and the hook claws are at least partially embedded in the groove.

[0011] Preferably, the upper cylinder includes a main body, both sides of which extend toward the lower cylinder to form vertical arms, the lower cylinder is embedded between the two sets of vertical arms, and the biasing member abuts against one side of the vertical arm close to the lower cylinder.

[0012] Preferably, the pre-tightening device includes a pre-tightening tube, a rubber rod and a gas generator, the pre-tightening tube is installed on the frame, the rubber rod is embedded in the pre-tightening tube, the generating end of the gas generator is connected to the pre-tightening tube through a fixing seat, a notch is provided on the side of the pre-tightening tube close to the frame, a gear is connected to the second side of the reel, the gear at least partially passes through the notch and extends into the interior of the pre-tightening tube, and the rubber rod is engaged with the gear.

[0013] Preferably, the lumbar pretensioner also includes a non-return mechanism, which includes a ratchet and a pawl. A rotating rod is connected to the first side of the reel, and the outer periphery of the rotating rod extends outward to form a plurality of clips. The rotating rod passes through the frame and the ratchet. A clip groove that cooperates with the plurality of clips is opened at the center of the ratchet so that the ratchet is driven to rotate synchronously when the reel rotates. The pawl is pivotally mounted on the frame, and the pawl cooperates with the ratchet so that the pawl can only rotate in one direction.

[0014] Preferably, the anti-return mechanism also includes a limit pin and a latch, the limit pin is installed on the frame, the limit pin limits the pawl so that the pawl is always in contact with the ratchet, and a lock hole that cooperates with the latch is provided on the rotating rod, and the latch limits the ratchet to prevent the ratchet from moving away from the rotating rod.

[0015] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0016] By arranging a clamping portion and a second limiting portion in the accommodating cavity of the reel, when the quick-insert end piece is inserted into the reel, the clamping portion cooperates with the limiting hook on the quick-insert end piece to realize a quick-insert connection between the quick-insert end piece and the reel, which can prevent the quick-insert end piece from being pulled out, and the second limiting portion cooperates with the first limiting portion on the quick-insert end piece to prevent the quick-insert end piece and the reel from being separated when the reel rotates. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 It is a structural schematic diagram of the seat belt lap pretensioner provided by this application;

[0019] Figure 2 It is a schematic diagram of the exploded structure of the seat belt lap pretensioner provided by the present application;

[0020] Figure 3 It is a schematic diagram of the exploded structure of the reel of the seat belt lap pretensioner provided by the present application;

[0021] Figure 4 It is a schematic structural diagram of the reel of the seat belt lap pretensioner provided by the present application;

[0022] Figure 5 This is a schematic structural diagram of the quick-insert end piece of the seat belt lap pretensioner provided in this application;

[0023] Figure 6 This is a cross-sectional view of the quick-insert end piece at AA of the seat belt lap pretensioner provided by the present application;

[0024] Figure 7 Schematic diagram of the structure of the quick-insert end piece of the seat belt lap pretensioner provided by the present application before, during and after insertion;

[0025] Figure 8 It is a structural schematic diagram of the anti-return mechanism of the seat belt lap pretensioner provided by the present application;

[0026] Figure 9 This is a schematic diagram of the structure of the pretensioning device of the seat belt lap pretensioner provided in the present application before and after activation.

[0027] In the figure, 1. frame; 2. reel; 21. upper cylinder; 211. main body; 212. vertical arm; 22. lower cylinder; 23. slide groove; 24. limiting claw; 241. hook claw; 25. biasing member; 26. second limiting part; 3. pre-tightening device; 31. pre-tightening tube; 32. gas generator; 33. rubber rod; 34. notch; 35. fixing seat; 36. protective cover; 4. webbing; 5. quick-insert end piece; 51. limiting hook; 52. main piece; 53. first limiting part; 54. groove; 55. insertion port; 6. anti-return mechanism; 61. ratchet; 62. pawl; 63. latch; 64. limiting pin; 7. rotating rod; 8. card strip; 9. lock hole; 10. gear. DETAILED DESCRIPTION

[0028] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0029] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0030] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0031] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0032] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples. However, one skilled in the art will appreciate that the aspects described can be practiced without these specific details.

[0033] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0034] like Figure 1-Figure 7 As shown, a seat belt lap pretensioner includes a frame 1, a reel 2 and a pretensioning device 3. One end of the seat belt is fixed to the reel 2, and the reel 2 is rotatably mounted on the frame 1. The frame 1 is mounted on the vehicle seat or the vehicle frame by bolts. The pretensioning device 3 is mounted on the frame 1 and cooperates with the reel 2. When braking, the reel 2 is driven to rotate relative to the frame 1 to further reel the seat belt webbing 4 onto the reel 2.

[0035] One end of the safety belt is inserted into the accommodating cavity of the reel 2 through a quick-insert end piece 5. The quick-insert end piece 5 includes a limiting hook 51 and a first limiting portion 53 for insertion. A clamping portion and a second limiting portion 26 are formed in the accommodating cavity. The clamping portion is configured to cooperate with the limiting hook 51 in the plane where the limiting hook 51 is located to limit the quick-insert end piece 5 from moving in a direction away from the accommodating cavity. The second limiting portion 26 is configured to cooperate with the first limiting portion 53 in the rotation direction of the reel 2 to further limit the movement of the quick-insert end piece 5.

[0036] By arranging a locking portion and a second limiting portion 26 in the accommodating cavity of the reel 2, when the quick-plug end piece 5 is inserted into the reel 2, the locking portion cooperates with the limiting hook 51 on the quick-plug end piece 5 to realize a quick-plug connection between the quick-plug end piece 5 and the reel 2. The locking portion limits the limiting hook 51, which can prevent the quick-plug end piece 5 from moving in the direction away from the accommodating cavity, thereby preventing the quick-plug end piece 5 from being pulled out. The second limiting portion 26 cooperates with the first limiting portion 53 on the quick-plug end piece 5. When braking, the pre-tightening device 3 drives the reel 2 to rotate relative to the frame 1. Since the second limiting portion 26 cooperates with the first limiting portion 53, the quick-plug end piece 5 and the reel 2 are relatively fixed. When the reel 2 rotates, the quick-plug end piece 5 is driven to rotate synchronously, and while the seat belt webbing 4 is wound up, the quick-plug end piece 5 and the reel 2 can be prevented from separating when the reel 2 rotates.

[0037] like Figure 2-Figure 7 As shown, in some embodiments, the quick-insert end piece 5 also includes a main piece 52 connected to the safety belt, and the main piece 52 is arranged in the same plane as the limit hook 51, and the first limit portion 53 is arranged on the main piece 52, and is configured to cooperate with the second limit portion 26 when the reel 2 rotates. By arranging the main piece 52 and the limit hook 51 in the same plane, and the first limit portion 53 is arranged on the main piece 52, when the quick-insert end piece 5 is inserted into the reel 2, the first limit portion 53 and the second limit portion 26 are in a separated state. When the reel 2 rotates, the second limit portion 26 rotates accordingly, and the second limit portion 26 moves in a direction close to the first limit portion 53. The second limit portion 26 cooperates with the first limit portion 53, thereby achieving relative fixation between the quick-insert end piece 5 and the reel 2, eliminating the gap and anti-falling of the quick-insert end piece 5 when the reel 2 rotates, thereby achieving pre-tightening.

[0038] It should be noted that, in other embodiments, the main piece 52 can also be set in a different plane from the limiting hook 51. In this case, the first limiting portion 53 can be configured so that when the quick-insert end piece 5 is inserted into the accommodating cavity, the first limiting portion 53 cooperates with the second limiting portion 26.

[0039] like Figure 4-Figure 5 As shown, in some embodiments, the first limiting portion 53 includes two groups of limiting holes opened on the main piece 52, and the main piece 52 is provided with an insertion port 55 for the webbing 4 to pass through, and the two groups of limiting holes are respectively arranged on both sides of the insertion port 55, and the second limiting portion 26 includes a limiting block corresponding to the limiting hole, and the limiting block is configured to be at least partially embedded in the limiting hole when the reel 2 rotates. By opening an insertion port 55 on the main piece 52, the webbing 4 passes through the insertion port 55 and is connected to the main piece 52, and limiting holes are respectively provided on both sides of the insertion port 55 to form the first limiting portion 53, and the second limiting portion 26 is formed by the limiting blocks corresponding to the limiting holes. The limiting block is embedded in the limiting hole when the reel 2 rotates, thereby achieving further fixation between the quick-insert end piece 5 and the reel 2.

[0040] It should be noted that the limiting hole is arranged as close as possible to the insertion opening 55 so that when the quick-insert end piece 5 is pulled by the webbing 4, the limiting hole can always cooperate with the limiting block.

[0041] like Figure 6As shown, in some embodiments, an inclined surface is formed on the inner top wall of the limiting hole, and the size of the limiting hole gradually becomes smaller in the direction away from the limiting block, so that the limiting block can be embedded in the limiting hole. By forming an inclined surface on the inner top wall of the limiting hole, and gradually tilting the surface downward in the direction away from the limiting block, the size of the limiting hole gradually becomes smaller, so that the limiting block can be easily embedded in the limiting hole during the rotation of the reel 2.

[0042] like Figure 3-Figure 4 As shown, in some embodiments, the reel 2 includes an upper cylindrical portion 21 and a lower cylindrical portion 22 that cooperate with each other, the accommodating cavity is formed in the upper cylindrical portion 21, and a slide groove 23 for radially limiting the engaging portion is formed at the upper cylindrical portion 21 and / or the lower cylindrical portion 22, so that the engaging portion moves along the axial direction of the reel 2, and a biasing member 25 is provided in the accommodating cavity, and the biasing member 25 always pushes the engaging portion to move in the direction close to the quick-insert end piece 5, and the reel 2 is formed by cooperating with the upper cylindrical portion 21 and the lower cylindrical portion 22, and the upper cylindrical portion 21 and / or a sliding groove 23 is formed along the axial direction of the reel 2 at the lower barrel 22, and the engaging part is at least partially embedded in the sliding groove 23. The sliding groove 23 radially limits the engaging part, which can prevent the engaging part from shifting during the rotation of the reel 2. At the same time, the sliding groove 23 can guide the engaging part, so that the engaging part can only move along the axial direction of the reel 2. At the same time, a biasing member 25 is provided in the cavity. The biasing member 25 always pushes the engaging part to move in the direction close to the quick-insert end piece 5, so that the engaging part and the limiting hook 51 are always in a mating state, which can prevent the quick-insert end piece 5 from being pulled out.

[0043] like Figure 3-Figure 7As shown, in some embodiments, the engaging portion includes two groups of limiting claws 24, and the two groups of limiting claws 24 are respectively arranged on opposite sides of the limiting hook 51. The opposite sides of the limiting hook 51 extend toward the direction close to the two groups of limiting claws 24 to form grooves 54, and the two groups of limiting claws 24 extend toward the direction close to the limiting hook 51 to form hook claws 241. The hook claws 241 are at least partially embedded in the grooves 54. By arranging limiting claws 24 on opposite sides of the limiting hook 51, grooves 54 that cooperate with the two groups of limiting claws 24 are respectively formed on both sides of the limiting hook 51. When the quick-insert end piece When the fast-connect end piece 5 is inserted into the reel 2, the limiting hook 51 contacts the limiting claw 24. As the fast-connect end piece 5 continues to be inserted, the limiting hook 51 presses the two sets of limiting claws 24 to slide along the slide groove 23 in the direction away from the limiting hook 51. The biasing member 25 is compressed, and the limiting hook 51 continues to move downward. When the limiting hook 51 moves to the specified position, the limiting claw 24 returns to the initial position under the action of the biasing member 25. The hook 241 is at least partially embedded in the groove 54. The limiting hook 51 and the limiting claw 24 are locked with each other, so that the fast-connect end piece 5 and the reel 2 are directly locked with each other, which can prevent the quick-connect end piece 5 from being pulled out.

[0044] like Figure 3-Figure 4 As shown, in some embodiments, the upper cylinder 21 includes a main body 211, and both sides of the main body 211 extend toward the direction close to the lower cylinder 22 to form vertical arms 212, and the lower cylinder 22 is embedded between the two groups of vertical arms 212, and the biasing member 25 abuts against the side of the vertical arm 212 close to the lower cylinder 22. The upper cylinder 21 includes a main body, and the opposite sides (left and right sides) of the main body 211 extend downward to form vertical arms 212, and a receiving area is formed between the two groups of vertical arms 212. The lower cylinder 22 is embedded in the receiving area between the two groups of vertical arms 212, thereby forming a complete cylindrical structure, the outer end of the biasing member 25 abuts against the inner wall of the vertical arm 212, and the inner end of the biasing member 25 abuts against the limiting claw 24, and the lower cylinder 22 and the upper cylinder 21 can be fixed by fasteners.

[0045] It should be noted that, in this embodiment, the biasing member 25 can be a spring, and a positioning column is provided on the side of the limiting claw 24 close to the spring. The spring is at least partially mounted on the outside of the positioning column. The positioning column can position the spring to avoid separation between the spring and the limiting claw 24.

[0046] like Figure 1-Figure 2 and Figure 9As shown, in some embodiments, the pre-tightening device 3 includes a pre-tightening tube 31, a rubber rod 33 and a gas generator 32, the pre-tightening tube 31 is installed on the frame 1, the rubber rod 33 is embedded in the pre-tightening tube 31, the generating end of the gas generator 32 is connected to the pre-tightening tube 31 through a fixing seat 35, the pre-tightening tube 31 is provided with a notch 34 on the side close to the frame 1, the second side of the reel 2 is connected to a gear 10, the gear 10 at least partially passes through the notch 34 and extends into the pre-tightening tube 31, and the rubber rod 33 is engaged with the gear 10; wherein, when the gas generator 32 is detonated, it pushes the rubber rod 33 to move along the inside of the pre-tightening tube 31, and the rubber rod 33 drives the gear 10 and the The reel 2 rotates so that the reel 2 winds the webbing 4. By setting a pre-tensioning device 3, when the vehicle braking causes the pre-tensioning device 3 to start, the gas generator 32 is ignited, and the gas generated by the gas generator 32 enters the pre-tensioning tube 31. Since a sealed cavity is formed between the pre-tensioning tube 31 and the rubber rod 33, the gas generated by the gas generator 32 will push the rubber rod 33 to move in the pre-tensioning tube 31. Since a notch 34 is provided on the pre-tensioning tube 31, a gear 10 is provided on the second side of the reel 2. The outer end of the gear 10 passes through the notch 34 and engages with the rubber rod 33. When the rubber rod 33 moves, it drives the gear 10 to rotate, and the gear 10 drives the reel 2 to rotate. The reel 2 winds the webbing 4, and the webbing 4 is pulled back, thereby realizing the pre-tensioning function.

[0047] like Figure 1-Figure 2 and Figure 9 As shown, in some embodiments, the pre-tightening mechanism further includes a protective sleeve 36 , which is sleeved on the outside of the gas generator 32 . By arranging the protective sleeve 36 on the outside of the gas generator 32 , the protective sleeve 36 can protect the gas generator 32 .

[0048] like Figure 1-Figure 2 and Figure 8As shown, in some embodiments, the lumbar pretensioner further includes a non-return mechanism 6, which includes a ratchet 61 and a pawl 62. A rotating rod 7 is connected to the first side of the reel 2, and the outer periphery of the rotating rod 7 extends outward to form a plurality of clips 8. The rotating rod 7 passes through the frame 1 and the ratchet 61. A clip groove that cooperates with the plurality of clips 8 is opened at the center of the ratchet 61, so that when the reel 2 rotates, the ratchet 61 is driven to rotate synchronously, and the pawl 62 is pivotally mounted on the frame 1, and the pawl 62 cooperates with the ratchet 61 so that the pawl 62 can only rotate in one direction. By providing the non-return mechanism 6, the reel 2 can only rotate in one direction. The anti-return mechanism 6 includes a ratchet 61 and a pawl 62 structure, by arranging a rotating rod 7 on the first side of the reel 2, the rotating rod 7 extends to the outside of the frame 1, and a plurality of clips 8 are formed on the outside of the rotating rod 7. A clip groove that cooperates with the clip 8 is provided at the center of the ratchet 61. When the rotating rod 7 passes through the ratchet 61, the clip 8 is embedded in the clip groove to achieve relative fixation between the rotating rod 7 and the ratchet 61, ensuring that the ratchet 61 can be driven to rotate by the rotating rod 7 when the reel 2 rotates. The pawl 62 is rotatably installed on the outer wall of the frame 1, and the pawl 62 cooperates with the ratchet 61 to ensure that the pawl 62 can only rotate in the direction of winding the webbing 4, thereby avoiding the situation where the reel 2 reverses and unwinds the webbing 4.

[0049] like Figure 1-Figure 2 and Figure 8 As shown, in some embodiments, the anti-return mechanism 6 further includes a limit pin 64 and a latch 63, the limit pin 64 is mounted on the frame 1, the limit pin 64 limits the pawl 62 so that the pawl 62 is always in contact with the ratchet 61, the rotating rod 7 is provided with a lock hole 9 that cooperates with the latch 63, the latch 63 limits the ratchet 61 to prevent the ratchet 61 from moving away from the rotating rod 7, and by setting the limit pin 64, the limit pin 64 is fixedly mounted on the frame On the outer wall of the 1, a limit pin 64 can limit the pawl 62, so that the pawl 62 can only rotate within a certain range, which can prevent the pawl 62 from separating from the ratchet 61, thereby ensuring that the pawl 62 can always be in contact with the ratchet 61, ensuring that the function of preventing the reel 2 from reversing is always maintained. By providing a lock hole 9 on the rotating rod 7, a lock latch 63 passes through the lock hole 9, and the lock latch 63 can limit the ratchet 61, preventing the ratchet 61 from moving along the axial direction of the rotating rod 7, thereby ensuring that the rotating rod 7 and the ratchet 61 are always relatively fixed.

[0050] The same or similar parts between the various embodiments in this specification can be referred to in conjunction with each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiments described later, since they correspond to the system, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0051] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A seat belt lap pretensioner, comprising a frame, a reel, and a pretensioning device, wherein one end of the seat belt is fixed to the reel, the reel is rotatably mounted on the frame, the pretensioning device is mounted on the frame and cooperates with the reel, and when braking, the reel is driven to rotate relative to the frame to further reel the seat belt webbing onto the reel, characterized in that: One end of the safety belt is inserted into the accommodating cavity of the reel through a quick-insert end piece, and the quick-insert end piece includes a limit hook and a first limit portion for insertion. A clamping portion and a second limit portion are formed in the accommodating cavity. The clamping portion is configured to cooperate with the limit hook in the plane where the limit hook is located to limit the movement of the quick-insert end piece in the direction away from the accommodating cavity. The second limit portion is configured to cooperate with the first limit portion in the rotation direction of the reel to further limit the movement of the quick-insert end piece.

2. The lumbar pretensioner according to claim 1, characterized in that The quick-insert end piece also includes a main piece connected to the safety belt, the main piece and the limiting hook are arranged in the same plane, the first limiting portion is arranged on the main piece, and is configured to cooperate with the second limiting portion when the reel rotates.

3. The lumbar pretensioner according to claim 2, characterized in that: The first limiting portion includes two groups of limiting holes opened on the main plate, and an insertion port for the webbing to pass through is opened on the main plate, and the two groups of limiting holes are respectively arranged on both sides of the insertion port, and the second limiting portion includes a limiting block corresponding to the limiting hole, and the limiting block is configured to be at least partially embedded in the limiting hole when the reel rotates.

4. The lumbar pretensioner according to claim 3, characterized in that: An inclined surface is formed on the inner top wall of the limiting hole. The size of the limiting hole gradually decreases in a direction away from the limiting block, so that the limiting block can be easily embedded in the limiting hole.

5. The lumbar pretensioner according to any one of claims 1 to 4, characterized in that: The reel includes an upper cylindrical portion and a lower cylindrical portion that cooperate with each other, the accommodating cavity is formed in the upper cylindrical portion, and a sliding groove for radially limiting the engaging portion is formed on the upper cylindrical portion and / or the lower cylindrical portion, so that the engaging portion moves along the axial direction of the reel, and a biasing member is provided in the accommodating cavity, and the biasing member always pushes the engaging portion to move in a direction close to the quick-insert end piece.

6. The lumbar pretensioner according to claim 5, characterized in that: The engaging portion includes two groups of limiting claws, which are respectively arranged on opposite sides of the limiting hook. The opposite sides of the limiting hook extend toward the direction close to the two groups of limiting claws to form grooves. The two groups of limiting claws extend toward the direction close to the limiting hook to form hook claws, and the hook claws are at least partially embedded in the grooves.

7. The lumbar pretensioner according to claim 6, characterized in that: The upper tube portion includes a main body, both sides of which extend toward the lower tube portion to form vertical arms, the lower tube portion is embedded between the two groups of vertical arms, and the biasing member abuts against one side of the vertical arm close to the lower tube portion.

8. The lumbar pretensioner according to any one of claims 1 to 4, characterized in that: The pre-tightening device includes a pre-tightening tube, a rubber rod and a gas generator. The pre-tightening tube is installed on the frame, the rubber rod is embedded in the pre-tightening tube, and the generating end of the gas generator is connected to the pre-tightening tube through a fixing seat. A notch is provided on the side of the pre-tightening tube close to the frame, and a gear is connected to the second side of the reel. The gear at least partially passes through the notch and extends into the interior of the pre-tightening tube, and the rubber rod is engaged with the gear.

9. The lumbar pretensioner according to claim 8, characterized in that The lumbar pretensioner also includes a non-return mechanism, which includes a ratchet and a pawl. A rotating rod is connected to the first side of the reel, and the outer periphery of the rotating rod extends outward to form a plurality of clips. The rotating rod passes through the frame and the ratchet. A clip groove that cooperates with the plurality of clips is opened at the center of the ratchet so that the ratchet is driven to rotate synchronously when the reel rotates. The pawl is pivotally mounted on the frame, and the pawl cooperates with the ratchet so that the pawl can only rotate in one direction.

10. The lumbar pretensioner according to claim 9, characterized in that The anti-return mechanism also includes a limit pin and a latch. The limit pin is installed on the frame. The limit pin limits the pawl so that the pawl is always in contact with the ratchet. A lock hole that cooperates with the latch is provided on the rotating rod. The latch limits the ratchet to prevent the ratchet from moving away from the rotating rod.

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