Vehicle seat belt pretensioner and vehicle seat

Abstract

The embodiment of the present specification provides a vehicle seat belt pretensioner and a vehicle seat. The pretensioner comprises a cylinder, a piston member and a gas generator. The cylinder is mounted on a vehicle body component through a bracket assembly. The cylinder is provided with an axial channel for the piston member to slide. The piston member is connected to a seat belt component to be tensioned through a tensioning cable. The gas generator is used to generate pressurized gas to drive the piston member to move in a tensioning direction. One end of the cylinder is provided with a sealing cover and the bracket assembly. The sealing cover at least partially extends into the cylinder and is blocked. The bracket assembly is a U-shaped plate-shaped component, comprising a first plate part, a second plate part and a connecting plate part. The ends of the first plate part and the second plate part form a clamping structure fixedly connected with the cylinder. The first plate part and the second plate part are provided with through holes accommodating inner gaskets, which are used for the bolts to pass through the inside and be connected with the vehicle body component. The pretensioner can be installed in the seat pipe column without occupying the space in the vehicle. The installation operation of the pretensioner is also relatively convenient.

Description

Technical Field

[0001] This manual relates to the field of vehicle safety technology, specifically to a vehicle seatbelt pretensioner and a vehicle seat. Background Technology

[0002] The seat belt lumbar pretensioner is the core component of a pretensioned seat belt system. Its core function is to quickly tighten the seat belt at the moment of a vehicle collision, firmly fixing the occupant to the seat, reducing forward displacement of the body, and thus reducing the risk of collision between the head, chest and other critical parts of the body and hard objects inside the vehicle.

[0003] Currently, lumbar pretensioners are generally installed on the outside of vehicle seats, which requires a certain amount of installation space. Due to the limited space in the vehicle, the installation of lumbar pretensioners is also relatively troublesome. Summary of the Invention

[0004] In view of this, the embodiments of this specification provide a vehicle seat belt pretensioner and a vehicle seat. The pretensioner can be installed inside the seat column without occupying interior space, and the installation and operation of the pretensioner are also relatively convenient.

[0005] This specification provides the following technical solution through its embodiments: a vehicle seatbelt pretensioner, comprising a cylinder, a piston, and a gas generator. The cylinder is mounted on a vehicle body component via a bracket assembly. The cylinder has an axial channel for the piston to slide. The piston is connected to a seatbelt component to be tensioned via a tensioning cable. The gas generator generates pressurized gas to drive the piston to move in the tensioning direction.

[0006] A sealing cover and a bracket assembly are provided at one end of the cylinder. The sealing cover extends at least partially into the cylinder and seals it. The bracket assembly is a U-shaped plate component, including a first plate portion, a second plate portion, and a connecting plate portion. The ends of the first plate portion and the second plate portion form a locking structure that is fixedly connected to the cylinder. The first plate portion and the second plate portion are provided with through holes for accommodating inner gaskets, for bolts to pass through their interiors and connect to the body components. The connecting plate portion is also provided with an opening. The tensioning cable passes through the opening in sequence, wraps around the outer periphery of the inner gasket, passes through the sealing cover, and connects to the piston component.

[0007] Preferably, the engaging structure includes an arc-shaped arm portion, and the sealing cover has a second axial step portion on the side away from the piston component. After the arc-shaped arm portion extends into the cylinder, it is nested on the outer periphery of the second axial step portion. The cylinder forms a groove on the side of the arc-shaped arm portion away from the piston component by at least part of a riveting process.

[0008] Preferably, the cylinder has an air inlet in the area between the sealing cover and the piston, which is connected to the outlet of the gas generator. The air inlet is provided with a releasable seal. The axial channel between the end of the sealing cover and the piston forms a sealed cavity. The sealed cavity is filled with a grease-based sealing substance. When the gas generator is actuated, pressurized gas can break through the releasable seal and enter the sealed cavity.

[0009] Preferably, the gas generator is disposed on one side of the piston in the tension direction, and its outlet end is connected to the axial channel on the side of the piston away from the gas generator through a first sealing channel, wherein the first sealing channel is located outside the axial channel.

[0010] Preferably, the cylinder includes an outer cylinder and an inner cylinder. The inner cylinder forms the axial channel. The inner cylinder is provided with an air inlet and an air outlet. The inner cylinder between the air inlet and the air outlet is provided with a partition to prevent gas from passing through. The cavity on the side of the partition away from the piston and the gap between the inner cylinder and the outer cylinder form the first sealing channel.

[0011] Preferably, the partition includes a baffle plate disposed near the air outlet, and a first stop portion is formed inwardly in the region of the inner cylinder near the first side of the baffle plate. The first stop portion abuts against the side of the baffle plate away from the gas generator to prevent the baffle plate from moving away from the gas generator.

[0012] Preferably, the partition further includes a first sealing ring, and the baffle extends toward the side of the gas generator to form a boss. The first sealing ring is sleeved on the outer periphery of the boss, and the first sealing ring is in sealing contact with the inner wall of the inner cylinder.

[0013] Preferably, the partition further includes a retaining spring, which is at least partially sleeved on the boss. The retaining spring extends toward the side of the gas generator and forms a plurality of elastic plates. Along the direction away from the boss, the plurality of elastic plates expand toward the direction close to the inner wall of the inner cylinder.

[0014] Preferably, the gas generator is coaxially arranged with the inner cylinder, and the gas generating end extends into the inner cylinder. A third sealing ring is fitted on the gas generator at the junction of the inner cylinder and the outer cylinder. The third sealing ring is in sealing contact with the end of the inner cylinder and the inner wall of the outer cylinder. The end of the outer cylinder is turned inward to form a flanged portion. The flanged portion abuts against the radial flange end of the gas generator. The outer cylinder is riveted to the radial flange to prevent the gas generator from moving away from the partition.

[0015] Preferably, the sealing cap includes a first axial step portion and a radial protrusion portion, the first axial step portion extending at least partially into the inner cylinder and sealing it, and the radial protrusion portion abutting against the inner wall of the outer cylinder and sealing the gap between the inner cylinder and the outer cylinder.

[0016] A vehicle seat includes a seat body and a pretensioner as described in any of the preceding claims. The pretensioner is mounted in a column of the seat body via a bracket assembly. The column has bolt holes. One end of an inner washer has a nut, and the other end abuts against the inner wall of the column. A bolt passes through the bolt holes and the inner washer and is fixedly connected to the nut.

[0017] Preferably, the other end of the inner washer is provided with a conforming structure that fits against the inner wall of the column around the bolt hole.

[0018] Compared with the prior art, the beneficial effects that at least one technical solution adopted in the embodiments of this specification can achieve include at least:

[0019] By setting up a bracket assembly, which is fixedly connected to the cylinder through a snap-fit ​​structure, the first and second plates are provided with through holes to accommodate the inner washer. Bolts pass through these through holes and the inner washer to connect with the body parts (seat column), ensuring the stability and reliability of the entire pretensioner system during vehicle operation. It does not occupy interior space and the installation and operation of the pretensioner are also relatively convenient. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is an exploded structural diagram of the vehicle seatbelt pretensioner provided in this application;

[0022] Figure 2 This is a cross-sectional view of the vehicle seatbelt pretensioner provided in this application;

[0023] Figure 3 This is a schematic diagram of the structure of the gas generator of the vehicle seat belt pretensioner provided in this application within the inner cylinder;

[0024] Figure 4 This is a schematic diagram showing the flow of sealing material after the gas generator of the vehicle seatbelt pretensioner provided in this application is ignited;

[0025] Figure 5This is a schematic diagram of the structure of the vehicle seat belt pretensioner installed in the seat column according to this application;

[0026] Figure 6 This is a structural schematic diagram of the support assembly provided in this application;

[0027] Figure 7 This is a schematic diagram of the structure of the bracket assembly and cylinder provided in this application after installation;

[0028] Figure 8 This is a cross-sectional view of the bracket assembly and cylinder provided in this application after installation.

[0029] In the diagram, 1. Outer cylinder; 101. Pressure groove; 2. Inner cylinder; 3. Gas generator; 4. Piston component; 41. Piston; 5. Tensioning cable; 51. Steel cable; 52. End plate; 6. Third sealing ring; 7. Snap ring; 71. Elastic plate; 8. First sealing ring; 9. Baffle plate; 10. Collar; 11. Second sealing ring; 12. Sealing cover; 121. First axial step; 122. Radial protrusion; 123. Second axial step; 13. Bracket assembly; 131. U-shaped plate component; 1311. First 1312. Second plate; 1313. Connecting plate; 1314. Opening; 132. Engaging structure; 1321. Arc-shaped arm; 133. Inner washer; 134. Nut; 135. Bolt; 136. Outer washer; 14. Sealing belt component; 15. Seal; 151. Sealing material; 16. Air outlet; 17. Air inlet; 18. First sealing channel; 19. First stop; 20. Flanged part; 21. Groove; 22. Fourth sealing ring; 23. Axial channel; 24. Tube column. Detailed Implementation

[0030] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0031] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one 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 aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0033] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0034] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.

[0035] The technical solutions provided by the various embodiments of this application are described below with reference to the accompanying drawings.

[0036] like Figures 1-2 As shown, a vehicle seatbelt pretensioner includes a cylinder, a piston 4, and a gas generator 3. The cylinder has an axial channel 23 for the piston 4 to slide. The piston 4 is connected to the seatbelt component 14 to be tensioned via a tensioning cable 5. The gas generator 3 generates pressurized gas to drive the piston 4 to move in the tensioning direction.

[0037] The gas generator 3 is disposed on one side of the tension direction of the piston 4, and its outlet end is connected to the axial channel 23 located on the side of the piston 4 away from the gas generator 3 through the first sealing channel 18. The first sealing channel 18 is located outside the axial channel 23.

[0038] The cylinder has an axial channel 23 for the piston 4 to slide. The piston 4 is connected to the seat belt component 14 to be tensioned via a tensioning cable 5 (such as a steel cable 51 and an end piece 52). The gas generator 3 is located on one side of the piston 4 in the tensioning direction, and its outlet end is connected to the axial channel 23 on the side of the piston 4 away from the gas generator 3 via a first sealing channel 18, which is located outside the axial channel 23. When a collision signal is detected, the gas generator 3 is triggered to generate pressurized gas. The gas enters the first sealing channel 18 from the outlet end of the gas generator 3. Since the first sealing channel 18 is connected to the axial channel 23 on the side of the piston 4 away from the gas generator 3, the gas smoothly enters this part of the axial channel 23, thereby pushing the piston 4 to move towards the gas generator 3. The piston 4 drives the seat belt component 14 to move via the tensioning cable 5, realizing the pre-tensioning operation of the seat belt webbing.

[0039] like Figures 1-2 As shown, in some embodiments, the cylinder includes an outer cylinder 1 and an inner cylinder 2. The inner cylinder 2 forms the axial channel 23. The inner cylinder 2 is provided with an air inlet 17 and an air outlet 16. The inner cylinder 2 located between the air inlet 17 and the air outlet 16 is provided with a partition to prevent gas from passing through. The cavity on the side of the partition away from the piston 4 and the gap between the inner cylinder 2 and the outer cylinder 1 form the first sealing channel 18.

[0040] When a collision signal is detected, the gas generator 3 is triggered and generates pressurized gas. After being discharged from the gas generator 3, the gas first reaches the outlet 16 of the inner cylinder 2. Due to the obstruction of the partition, the gas cannot directly pass through the inner cylinder 2 to the area where the piston 4 is located. Instead, it enters the first sealed channel 18 formed by the cavity on the side of the partition away from the piston 4 and the gap between the outer cylinder 1 and the inner cylinder 2 through the outlet 16. The gas flows along the first sealed channel 18 and finally reaches the inlet 17 of the inner cylinder 2. After entering the interior of the inner cylinder 2 through the inlet 17, the gas pushes the piston 4 to move in the tensioning direction (i.e., towards the gas generator 3). The piston 4 is connected to the seat belt component 14, which is to be tensioned, through the tensioning cable 5. The piston 4 drives the seat belt component 14 to move, thereby realizing the pretensioning function of the seat belt, restricting and protecting the vehicle occupants.

[0041] By setting up a partition and a first sealing channel 18, the flow path of the gas is precisely controlled, so that the gas can enter the first sealing channel 18 through the outlet 16 in a predetermined direction, and then enter the inner cylinder 2 through the inlet 17 to drive the piston 4. The gap between the inner cylinder 2 and the outer cylinder 1 is used as a partial sealing channel, which avoids the problems of increased cost and excessive installation space due to setting up a gas guiding structure.

[0042] like Figures 1-3 As shown, in some embodiments, the partition includes a baffle 9 disposed near the air outlet 16, and the inner cylinder 2 has a first stop portion 19 formed inwardly in the area near the first side of the baffle 9. The first stop portion 19 abuts against the side of the baffle 9 away from the gas generator 3 to prevent the baffle 9 from moving away from the gas generator 3. When the gas generator 3 is triggered to generate pressurized gas, the presence of the baffle 9 can isolate the gas and prevent it from flowing directly in the axial channel 23. As the inner cylinder 2 contracts inward to form a first stop 19, and the first stop 19 abuts against the side of the baffle 9 away from the gas generator 3, when the gas exerts pressure on the baffle 9 and has a tendency to push the baffle 9 in a direction away from the gas generator 3 (i.e., in the opposite direction to the movement direction of the piston 4), the first stop 19 can block the movement of the baffle 9, ensuring that the baffle 9 will not be displaced or loosened due to the impact of the gas when the gas generator 3 is triggered to generate pressure. This allows the gas to enter the first sealed channel 18 through the outlet 16 and then enter the inner cylinder 2 through the inlet 17, pushing the piston 4 to move in the tensioning direction.

[0043] like Figures 1-3 As shown, in some embodiments, the partition further includes a first sealing ring 8. The baffle 9 extends towards the gas generator 3 and forms a boss. The first sealing ring 8 is fitted around the outer periphery of the boss, and the first sealing ring 8 makes sealing contact with the inner wall of the inner cylinder 2. The boss on the side of the baffle 9 near the gas generator 3 facilitates the installation of the first sealing ring 8. The sealing contact between the first sealing ring 8 and the inner wall of the inner cylinder 2 forms a sealing barrier. When the gas generator 3 generates high-pressure gas, it can effectively prevent gas leakage from the gap between the baffle 9 and the inner wall of the inner cylinder 2, ensuring that the gas can be concentrated and drive the piston 4 to move along the designed path.

[0044] like Figures 1-3 As shown, in some embodiments, the partition further includes a retaining spring 7, which is at least partially sleeved on the boss. The retaining spring 7 extends towards the side of the gas generator 3 and forms a plurality of elastic plates 71. Along the direction away from the boss, the plurality of elastic plates 71 expand towards the inner wall of the inner cylinder 2. Along the direction near the gas generator 3, the elastic plates 71 of the retaining spring 7 expand towards the inner wall of the inner cylinder 2. During installation, the retaining spring 7 moves towards the inside of the inner cylinder 2. Due to the structural design of the elastic plates 71, it does not generate much resistance. After installation, if the baffle 9 tends to move towards the gas generator 3, the elastic plates 71 will generate a certain force with the inner wall of the inner cylinder 2, thereby preventing the baffle 9 from moving.

[0045] like Figures 1-2 As shown, in some embodiments, the gas generator 3 is coaxially arranged with the inner cylinder 2, and the gas generating end extends into the inner cylinder 2. A third sealing ring 6 is fitted on the gas generator 3 at the junction of the inner cylinder 2 and the outer cylinder 1. The third sealing ring 6 is in sealing contact with the end of the inner cylinder 2 and the inner wall of the outer cylinder 1. The end of the outer cylinder 1 is turned inward to form a flange 20. The flange 20 abuts against the flange end of the gas generator 3. The outer cylinder 1 is riveted to the flange to prevent the gas generator 3 from moving away from the partition. When the gas generator 3 is working, the internal pressure will exert an outward thrust on it. The contact between the flange 20 of the outer cylinder 1 and the flange end of the gas generator 3, as well as the riveting between the two, form a stable mechanical connection structure, which effectively prevents the gas generator 3 from moving away from the partition under the action of internal pressure, ensuring that the gas generator 3 always stays in the correct position. At the same time, a third sealing ring 6 is provided. The third sealing ring 6 prevents gas from leaking out from the gap at the junction of the inner cylinder 2 and the outer cylinder 1 by sealing contact with the end of the inner cylinder 2 and the inner wall of the outer cylinder 1, ensuring that the gas can be concentrated and enter the inner cylinder 2.

[0046] The third sealing ring 6 forms a reliable sealing space by sealing the end of the inner cylinder 2 and the inner wall of the outer cylinder 1. This ensures that the pressurized gas generated by the gas generator 3 will not leak from the junction of the inner cylinder 2 and the outer cylinder 1, and can enter the interior of the inner cylinder 2 to drive the piston. This improves the gas utilization efficiency and ensures that the seat belt pretensioner can generate sufficient pretension force in a short time.

[0047] The flange 20 at the end of the outer cylinder 1 abuts against the flange end of the gas generator 3, and the riveting process provides a stable fixation for the gas generator 3. During vehicle operation, when subjected to various vibrations and impacts, this prevents the gas generator 3 from shifting or loosening due to vibration, ensuring that the relative position of the gas generator 3 and the inner cylinder 2 remains unchanged. Even in extreme cases, such as severe collisions, the gas generator 3 can operate stably.

[0048] like Figures 1-2 As shown, in some embodiments, a sealing cap 12 and a bracket assembly 13 are provided at the end of the inner cylinder 2 away from the gas generator 3. The bracket assembly 13 extends at least partially into the outer cylinder 1 and is fixed therein. The sealing cap 12 includes a first axial step portion 121 and a radial protrusion 122. The first axial step portion 121 extends at least partially into the inner cylinder 2 and seals it. The radial protrusion 122 abuts against the inner wall of the outer cylinder 1 and seals the gap between the inner cylinder 2 and the outer cylinder 1. The tensioning cable 5 passes through the bracket assembly 13 and the sealing cap 12 and is connected to the piston component 4.

[0049] By setting a sealing cover 12 and a bracket assembly 13, the portion of the bracket assembly 13 extending into the cylinder cooperates with the sealing cover 12, and the bracket assembly 13 is fixed relative to the cylinder. The sealing cover 12 includes a first axial step portion 121 and a radial protrusion 122. The first axial step portion 121 extends at least partially into the inner cylinder 2 and seals it to prevent gas from escaping from that end. At the same time, the radial protrusion 122 abuts tightly against the inner wall of the outer cylinder 1, which not only enhances the stability of the structure but also seals the gap between the inner cylinder 2 and the outer cylinder 1, ensuring that the gas can only flow along a predetermined path. When the gas flows into the inner cylinder 2 through the air inlet 17, the gas compresses the sealing cover 12. Due to the presence of the bracket assembly 13, the seal can be prevented from sliding in the inner cylinder 2, thus preventing the seal from separating from the inner cylinder 2.

[0050] A second sealing ring 11 is provided on the sealing cover 12. The second sealing ring 11 is sleeved on the outer periphery of the first axial step portion 121. Its special structural design makes the two sides of the second sealing ring 11 in close contact with the sealing cover 12 and the end of the inner cylinder 2, respectively. At the same time, the outer periphery of the second sealing ring 11 also forms a sealing contact with the inner wall of the outer cylinder 1, so that a relatively closed space is formed between the inner cylinder 2, the outer cylinder 1, the sealing cover 12 and the second sealing ring 11, preventing the gas in the inner cylinder 2 from leaking to the outside, ensuring that the gas can concentrate to drive the piston 4 to move, so that the piston 4 can obtain sufficient power in a shorter time, and drive the tensioning cable 5 to quickly tighten the safety belt.

[0051] like Figures 1-2 and Figure 4 As shown, in some embodiments, a releasable seal 15 is provided at the air inlet 17, and the axial channel 23 between the end of the sealing cover 12 and the piston 4 forms a sealed cavity. The sealed cavity is filled with a grease-based sealing substance 151. When the gas generator 3 is actuated, pressurized gas can break through the releasable seal 15 and enter the sealed cavity.

[0052] The seal 15, the sealing cap 12, and the piston 4 together form a sealed cavity within the inner cylinder 2. This sealed cavity is filled with a grease-based sealing substance 151. This grease-based sealing substance 151 has specific physical properties, can flow under certain pressure, and possesses good sealing performance. It can fill various gaps in the product to achieve a sealing effect. The specific principle is as follows:

[0053] When the gas generator ignites at point 3, it rapidly generates a large amount of pressurized gas. This gas flows to the air inlet 17. As the pressurized gas continuously pours in, it exerts sufficient pressure on the seal 15, causing it to be released. After the seal 15 is released, the grease-like sealing substance begins to flow within the sealed cavity under the pressure of the pressurized gas. Preferably, the seal 15 can be a flexible tubular or bag-like component, using its circumferentially closed curved surface to block the air inlet 17. Its interior forms a space for storing the sealing substance 151. When impacted by the pressurized gas, the seal 15 is ruptured, releasing the sealing substance 151.

[0054] The released grease-based sealing material, propelled by pressurized gas, flows along the sealed cavity and gradually diffuses into various gaps in the product. For example, it fills the gaps between the seal and tension cable 5, inner cylinder 2, and between the piston and tension cable 5, inner cylinder 2, etc. Due to the grease-like properties of the sealing material, it can adapt well to gaps of various shapes and sizes, tightly adhering to the gap surface to form an effective sealing layer. This prevents gas from leaking out of these gaps, ensuring that the gas can drive the piston and other components to move as designed, thus achieving the pre-tensioning function of the seatbelt.

[0055] By using a sealing substance, which is precisely released and fills the gaps under pressurized gas, gas leakage from the gaps in the sealing cap 12 and piston 4, and other related components, can be effectively prevented. During the operation of the pretensioner, the pressurized gas generated by the gas generator 3 is the power source that drives the piston and achieves seat belt pretensioning. If gas leaks, the gas pressure will drop, failing to provide sufficient driving force to the piston, thus affecting the pretensioning effect of the seat belt. After the sealing substance fills the gaps, it forms a reliable sealing barrier, ensuring that all the gas is used to drive the piston, improving gas utilization efficiency, and enabling the pretensioner to complete the seat belt pretensioning action in a shorter time. At the same time, the grease-based sealing substance has good fluidity and adaptability, and can fill gaps of various shapes and sizes. Whether it is a regular cylindrical gap or an irregular irregular gap, the sealing substance can fill it tightly with its own properties, forming a uniform sealing layer. This allows the pretensioner to achieve good sealing effects in different models and designs of vehicles, improving the product's versatility and adaptability.

[0056] like Figures 1-2As shown, in some embodiments, the piston component 4 includes a piston 41, a collar 10, and a fourth sealing ring 22. The tensioning cable 5 passes through a through hole in the piston 41 and is connected to the collar 10. A groove 21 is formed on the outer periphery of the piston 41, and the fourth sealing ring 22 is at least partially embedded in the groove 21. The outer periphery of the fourth sealing ring 22 is in sealing contact with the inner wall of the inner cylinder 2. The tensioning cable 5 passes through the through hole in the piston 41 and is fixedly connected to the collar 10. When the piston 41 is pushed by gas pressure and moves, it transmits power to the tensioning cable 5 through the collar 10, ensuring that the movement of the piston 41 can drive the tensioning cable 5 to move synchronously. The piston 41 has a groove 21 of a specific shape on its outer periphery. The fourth sealing ring 22 is at least partially embedded in the groove 21. During the movement of the piston 41, the outer periphery of the fourth sealing ring 22 always maintains a tight sealing contact with the inner wall of the inner cylinder 2. When gas enters the inner cylinder 2 and pushes the piston 41, the fourth sealing ring 22 can effectively prevent gas from leaking out from the gap between the piston 41 and the inner wall of the inner cylinder 2, ensuring that all the gas is used to push the piston to move.

[0057] like Figures 1-2 and Figures 6-8 As shown, in some embodiments, the bracket assembly 13 is a U-shaped plate component 131, including a first plate portion 1311, a second plate portion 1312, and a connecting plate portion 1313. The ends of the first plate portion 1311 and the second plate portion 1312 form a locking structure 132 that is fixedly connected to the outer cylinder 1. The first plate portion 1311 and the second plate portion 1312 are provided with through holes for accommodating the inner washer 133, for allowing the bolt 135 to pass through their interior and connect to the body component. The connecting plate portion 1313 is also provided with an opening 1314, through which the tensioning cable 5 passes sequentially through the opening 1314, around the outer periphery of the inner washer 133, through the sealing cover 12, and then connects to the piston component 4.

[0058] The ends of the first plate portion 1311 and the second plate portion 1312 form a locking structure 132. The bracket assembly 13 is securely connected to the outer cylinder 1 through the locking structure 132, and is also fastened to the body components by bolts 135, ensuring the stability and reliability of the entire pretensioner system during vehicle operation. The first plate portion 1311 and the second plate portion 1312 are provided with through holes for accommodating inner washers 133. Bolts 135 pass through these through holes and the inner washers 133 to connect to body components (such as seat columns, body floor panels, etc.). The connecting plate 1313 has an opening 1314. The tension cable 5 (steel cable) passes through the opening 1314, wraps around the outer periphery of the inner washer 133, passes through the sealing cover 12, and then connects to the piston 4. This guide design ensures the smooth movement of the tension cable 5 during the pre-tensioning process and effectively transmits the pre-tensioning force generated by the movement of the piston 4. It can also maintain a small installation size in the circumferential direction to fit into narrow spaces, such as the seat column or the B-pillar of the vehicle.

[0059] like Figures 1-2 and Figures 6-8 As shown, in some embodiments, the engaging structure 132 includes an arc-shaped arm 1321, and the sealing cover 12 has a second axial step 123 on the side away from the piston 4. The arc-shaped arm 1321 extends into the outer cylinder 1 and is nested around the outer periphery of the second axial step 123. The outer cylinder 1 forms a groove 101 on the side of the arc-shaped arm 1321 away from the piston 4 by a riveting process.

[0060] The engaging structure 132 includes an arc-shaped arm 1321, which forms a tight nested connection with the sealing cap 12 and the outer cylinder 1. The arc-shaped arm 1321 has a certain degree of elasticity and rigidity, and can undergo moderate deformation during assembly to adapt to the outer peripheral shape of the second axial step portion 123. During assembly, the arc-shaped arm 1321 extends into the outer cylinder 1 and is precisely nested around the outer periphery of the second axial step portion 123. The outer cylinder 1 is at least partially riveted to form a groove 101 on the side of the arc-shaped arm 1321 away from the piston component 4. The riveting process, through local deformation of the outer cylinder 1, forms a groove 101 that mates with the arc-shaped arm 1321, thereby further fixing the position of the engaging structure 132.

[0061] In summary, the aforementioned pretensioners can be installed in the vehicle body structure or in the seat column, depending on the actual situation. The following section will elaborate on the installation in the seat column:

[0062] like Figures 1-8As shown in the figure, this specification provides a vehicle seat, including a seat body and a pretensioner as described in any of the above claims. The pretensioner is mounted in the column 24 of the seat body via a bracket assembly 13. The column 24 is provided with bolt holes. One end of the inner washer 133 is provided with a nut 134, and the other end abuts against the inner wall of the column 24. The bolt 135 passes through the bolt hole and the inner washer 133 and is fixedly connected to the nut 134.

[0063] In practice, the other end of the inner washer 133 is provided with a conforming structure that fits against the inner wall of the column 24 around the bolt hole.

[0064] The pretensioner is installed in the column of the seat body via the bracket assembly 13. The U-shaped plate component 131 in the bracket assembly 13 plays the main supporting and positioning role. Its special structural design allows the pretensioner to be stably installed in the column. The side of the U-shaped plate component 131 near the cylinder extends to form a locking structure 132. The locking structure 132 extends into the cylinder and cooperates with the sealing cover 12. This cooperation not only provides lateral positioning of the cylinder from a structural perspective, preventing the cylinder from wobbling left and right in the column 24, but also blocks the sealing cover 12, preventing the sealing cover 12 from sliding in the inner cylinder 2.

[0065] The first end of the inner washer 133 is in contact with the inner wall of the tube column 24. Through the friction and contact force between the inner washer 133 and the inner wall of the tube column 24, axial or radial movement of the U-shaped plate component 131 within the tube column is prevented, thus ensuring the overall stability of the pretensioner installation. A nut 134 is located at the second end of the inner washer 133, and an outer washer 136 is fitted against the outer side of the vehicle seat tube column 24. A bolt 135 passes through the outer washer 136 and the inner washer 133 and engages with the nut 134. When the bolt 135 is tightened, the outer washer 136 and the inner washer 133 are compressed by the bolt 135, generating a pretensioning force that tightly fixes the U-shaped plate component 131 within the tube column 24. This ensures that the pretensioner will not loosen or fall off due to vibration, bumps, or other factors during vehicle operation.

[0066] It should be noted that the engagement of the locking structure 132 with the sealing cap 12, the fit of the inner washer 133 with the inner wall of the tube column 24, and the connection of the bolt 135 and the nut 134 achieve multi-directional positioning of the pretensioner within the tube column 24. Whether in the lateral, axial, or radial direction, the pretensioner can be effectively prevented from moving, thus improving the stability of the pretensioner installation. During vehicle operation, even when encountering complex road conditions and strong vibrations, the pretensioner can always remain in the correct position, ensuring normal triggering when needed.

[0067] The same or similar parts between the various embodiments in this specification can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the method embodiments described later are relatively simple in description since they correspond to the system, and relevant parts can be referred to the descriptions in the system embodiments.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A vehicle seatbelt pretensioner, comprising a cylinder, a piston (4), and a gas generator (3), wherein the cylinder is mounted on a vehicle body component via a bracket assembly (13), the cylinder having an axial channel (23) for sliding of the piston (4), the piston (4) being connected to a seatbelt component (14) to be tensioned via a tensioning cable (5), and the gas generator (3) generating pressurized gas to drive the piston (4) to move in the tensioning direction, characterized in that, A sealing cap (12) and a bracket assembly (13) are provided at one end of the cylinder. The sealing cap (12) extends at least partially into the cylinder and seals it. The bracket assembly (13) is a U-shaped plate component (131), including a first plate portion (1311), a second plate portion (1312), and a connecting plate portion (1313). The ends of the first plate portion (1311) and the second plate portion (1312) form a locking structure (132) that is fixedly connected to the cylinder. The first plate portion (1311) and the second plate portion (1312) are provided with through holes for accommodating an inner washer (133) for a bolt (135) to pass through and connect to the body component. The connecting plate portion (1313) is also provided with an opening (1314). The tensioning cable (5) passes through the opening (1314), around the outer periphery of the inner washer (133), passes through the sealing cap (12), and connects to the piston component (4).

2. The vehicle seatbelt pretensioner according to claim 1, characterized in that, The engaging structure (132) includes an arc-shaped arm (1321), and the sealing cover (12) has a second axial step (123) on the side away from the piston (4). The arc-shaped arm (1321) extends into the cylinder and is nested on the outer periphery of the second axial step (123). The cylinder forms a groove (101) on the side of the arc-shaped arm (1321) away from the piston (4) by a riveting process.

3. The vehicle seatbelt pretensioner according to claim 2, characterized in that, The cylinder is provided with an air inlet (17) in the area between the sealing cover (12) and the piston (4), which is connected to the air outlet of the gas generator (3). A releasable seal (15) is provided at the air inlet (17). The axial channel (23) between the end of the sealing cover (12) and the piston (4) forms a sealed cavity. The sealed cavity is filled with a grease-based sealing substance (151). When the gas generator (3) is actuated, the pressurized gas can break through the releasable seal (15) and enter the sealed cavity.

4. The vehicle seatbelt pretensioner according to any one of claims 1-3, characterized in that, The gas generator (3) is disposed on one side of the piston (4) in the tension direction, and its outlet end is connected to the axial channel (23) on the side of the piston (4) away from the gas generator (3) through the first sealing channel (18). The first sealing channel (18) is located outside the axial channel (23).

5. The vehicle seatbelt pretensioner according to claim 4, characterized in that, The cylinder includes an outer cylinder (1) and an inner cylinder (2). The inner cylinder (2) forms the axial channel (23). The inner cylinder (2) is provided with an air inlet (17) and an air outlet (16). The inner cylinder (2) located between the air inlet (17) and the air outlet (16) is provided with a partition to prevent gas from passing through. The cavity on the side of the partition away from the piston (4) and the gap between the inner cylinder (2) and the outer cylinder (1) form the first sealing channel (18).

6. The vehicle seatbelt pretensioner according to claim 5, characterized in that, The partition includes a baffle (9) disposed near the air outlet (16). The inner cylinder (2) is formed by a first stop (19) that tapers inward toward the first side of the baffle (9). The first stop (19) abuts against the side of the baffle (9) away from the gas generator (3) to prevent the baffle (9) from moving away from the gas generator (3).

7. The vehicle seatbelt pretensioner according to claim 6, characterized in that, The partition also includes a first sealing ring (8), and the baffle (9) extends toward the side of the gas generator (3) to form a boss. The first sealing ring (8) is sleeved on the outer periphery of the boss, and the first sealing ring (8) is in sealing contact with the inner wall of the inner cylinder (2).

8. The vehicle seatbelt pretensioner according to claim 7, characterized in that, The partition also includes a retaining ring (7), which is at least partially sleeved on the boss. The retaining ring (7) extends toward the side of the gas generator (3) and forms a plurality of elastic pieces (71). Along the direction away from the boss, the plurality of elastic pieces (71) expand toward the direction close to the inner wall of the inner cylinder (2).

9. The vehicle seatbelt pretensioner according to claim 8, characterized in that, The gas generator (3) is coaxially arranged with the inner cylinder (2), and the gas generating end extends into the inner cylinder (2). The gas generator (3) is fitted with a third sealing ring (6) at the junction of the inner cylinder (2) and the outer cylinder (1). The third sealing ring (6) is in sealing contact with the end of the inner cylinder (2) and the inner wall of the outer cylinder (1). The end of the outer cylinder (1) is turned inward to form a flange (20). The flange (20) abuts against the radial flange end of the gas generator (3). The outer cylinder (1) is riveted to the radial flange to prevent the gas generator (3) from moving away from the partition.

10. The vehicle seatbelt pretensioner according to claim 5, characterized in that, The sealing cap (12) includes a first axial step portion (121) and a radial protrusion (122), the first axial step portion (121) extending at least partially into the inner cylinder (2) and sealing it, and the radial protrusion (122) abutting against the inner wall of the outer cylinder (1) and sealing the gap between the inner cylinder (2) and the outer cylinder (1).

11. A vehicle seat, characterized in that, The device includes a seat body and a pretensioner as described in any one of claims 1-9. The pretensioner is mounted in the column (24) of the seat body via a bracket assembly (13). The column (24) has bolt holes. One end of the inner washer (133) is provided with a nut (134), and the other end abuts against the inner wall of the column (24). The bolt (135) passes through the bolt holes and the inner washer (133) and is fixedly connected to the nut (134).

12. A vehicle seat according to claim 11, characterized in that, The other end of the inner washer (133) is provided with a conforming structure that fits against the inner wall of the column (24) around the bolt hole.

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