Pre-tensioning device and pre-tensioning retractor

Abstract

The embodiment of the invention provides a pre-tensioning device and a pre-tensioning retractor, the pre-tensioning device comprises a gear, a pre-tensioning pipe, a gas generator, a driving piece and a sealing piece, the gas generator is fixed at one end of the pre-tensioning pipe, and the driving piece comprises a polymer rod capable of plastically deforming; an actuating end close to the gas generator and an ejection end close to the other end of the pre-tightening pipe are formed in the pre-tightening pipe, the gear is connected with a reel used for winding the safety belt, when the gas generator actuates, the driving part is pushed to be meshed with the gear, so that the reel is driven to rotate to wind the safety belt, and the driving part is made of thermoplastic materials. An annular groove is formed in the periphery of the actuating end, the sealing piece is arranged in the annular groove in an embedded mode and abuts against the inner wall of the pre-tightening pipe, and the sealing piece is made of thermosetting materials. The sealing piece is made of a thermosetting material and can not deform under high-temperature gas, the sealing effect between the driving piece and the pre-tightening pipe is guaranteed, gas leakage is avoided, and the gas always has high thrust on the driving piece.

Description

Technical Field

[0001] This specification relates to the field of vehicle safety technology, and in particular to a pretensioning device and a pretensioning retractor. Background Art

[0002] Seatbelt pretensioners are a core component of modern vehicle safety systems. They rapidly respond to collision signals, tightening the seatbelts at the moment of an accident, securing the driver and passengers securely in their seats and significantly reducing the risk of collision injuries. Currently, most pretensioners utilize a gas generator's explosive charge to rapidly tighten the seatbelt, eliminating the gap between the belt and the body. However, the detonation of the gas generator generates a significant amount of heat, which can damage the driver and seals, resulting in a poor seal. Summary of the Invention

[0003] In view of this, the embodiments of this specification provide a pre-tensioning device and a pre-tensioning retractor, in which the sealing member is made of thermosetting material and can remain unchanged under high-temperature gas, thereby ensuring the sealing effect between the driving member and the pre-tensioning tube, avoiding gas leakage, and ensuring that the gas always has a strong thrust on the driving member.

[0004] The embodiments of this specification provide the following technical solutions: a pretensioning device, comprising a gear, a pretensioning tube, a gas generator, a driving member, and a sealing member, wherein the gas generator is fixed to one end of the pretensioning tube, the driving member comprises a polymer rod capable of plastic deformation, placed in the pretensioning tube, and formed with an actuating end close to the gas generator and an ejection end close to the other end of the pretensioning tube, the gear being connected to a reel for winding a seat belt, wherein when the gas generator is actuated, the driving member is pushed to engage with the gear, thereby driving the reel to rotate and rewind the seat belt,

[0005] The driving member is made of thermoplastic material, an annular groove is provided on the outer periphery of the actuating end, the sealing member is nested in the annular groove and abuts against the inner wall of the preload tube, and the sealing member is made of thermosetting material.

[0006] Preferably, the actuating end is provided with a protective member, and the protective member has a protective portion covering the entire end surface of the actuating end.

[0007] Preferably, a mounting slot is formed on the end surface of the actuating end, and the protective member further comprises a mounting portion connected to the protective portion, and the mounting portion is fixed in the mounting slot.

[0008] Preferably, the actuating end protrudes radially outward compared to the ejection end, and a stopping structure is provided on the preload tube, and the stopping structure is configured to allow the ejection end to pass through but prevent the actuating end from passing through.

[0009] Preferably, the pretensioning device further includes a guide member, which is arranged at the other end of the pretensioning tube and includes a guide bevel placed outside the pretensioning tube and a stop portion extending into the interior of the pretensioning tube, the guide bevel is used to guide the driving member to engage with the gear, and the stop portion is embedded between the outer periphery of the ejection end and the inner wall of the pretensioning tube, and is configured as the stop structure.

[0010] Preferably, the port at the other end of the preload tube partially extends outward to form an extension portion, and the guide member is fixed on the extension portion.

[0011] Preferably, the stopping structure includes a plurality of hooks provided at the other end of the preload tube, the hooks extending toward the radial inner side of the preload tube, and the distance between the hooks and the inner wall of the preload tube or the corresponding hooks is greater than the outer diameter of the ejection end and smaller than the outer diameter of the actuating end;

[0012] Alternatively, the stop structure includes a constricted portion, which is formed by an inward depression near the other end of the preload tube, and the inner diameter of the constricted portion is larger than the outer diameter of the ejection end and smaller than the outer diameter of the actuating end;

[0013] Alternatively, the stopping structure includes a contraction portion arranged at the other end of the preload tube, and the inner diameter of the contraction portion gradually decreases in the direction away from the other end of the preload tube. The inner diameter of the contraction portion is larger than the outer diameter of the ejection end and smaller than the outer diameter of the actuating end.

[0014] Preferably, the pre-tensioning device further comprises a cover shell, and the driving member moves along the inner wall of the cover shell after being discharged through the pre-tensioning pipe, thereby driving the gear to rotate.

[0015] A pretensioning retractor comprises a frame, a reel and a pretensioning device as described above, wherein the reel is rotatably mounted on the frame, the gear is mounted on the end of the reel, and the pretensioning tube is mounted on the frame.

[0016] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0017] After the gas generator is ignited, the generated gas pushes the driver to be discharged from the pre-tensioning tube. The driver engages with the gear, driving the gear to rotate, causing the reel to rotate and rewind the seat belt. The seal is made of thermosetting material and can remain unchanged under high-temperature gas, ensuring the sealing effect between the driver and the pre-tensioning tube, avoiding gas leakage, and ensuring that the gas always has a strong thrust on the driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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.

[0019] Figure 1 is a cross-sectional view of the pretensioning device provided by the present application;

[0020] Figure 2 It is a structural schematic diagram of the pre-tensioning device provided in this application;

[0021] Figure 3 This is a schematic diagram of the internal structure of the pretensioning tube of the pretensioning device provided by the present application;

[0022] Figure 4 This is a schematic structural diagram of the sealing member of the pre-tensioning device provided by the present application being installed on the actuating end;

[0023] Figure 5 This is a schematic diagram of the structure of the protective member of the pre-tensioning device provided by the present application after being matched with the actuating end;

[0024] Figure 6 This is a schematic diagram of the structure of the pretensioning device provided by the present application after the guide member and the pretensioning tube are installed in coordination;

[0025] Figure 7 is a structural schematic diagram of the stopper portion of the guide member of the pretensioning device provided by the present application;

[0026] Figure 8 This is a structural schematic diagram of the pre-tensioning device provided in the present application when the stopping structure is a hook;

[0027] Figure 9 This is a structural schematic diagram of the pre-tensioning device provided by the present application when the stop structure is a constricted neck;

[0028] Figure 10 Schematic diagram of the structure of the pre-tensioning device provided by the present application when the actuating end has different shapes;

[0029] Figure 11 It is a schematic diagram of the exploded structure of the pre-tensioning retractor provided in this application.

[0030] In the figure, 1. frame; 21. reel; 22. gear; 3. preload tube; 31. extension portion; 4. gas generator; 5. cover; 6. guide member; 61. guide slope; 62. stop portion; 7. drive rod; 81. actuating end; 82. ejection end; 9. sealing member; 10. annular groove; 11. mounting slot; 12. protective member; 121. protective portion; 122. mounting portion; 13. hook; 14. neck portion; 15. contraction portion. DETAILED DESCRIPTION

[0031] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0037] like Figure 1-Figure 4 As shown, a pretensioning device includes a gear 22, a pretensioning tube 3, a gas generator 4, a driving member and a sealing member 9. The gas generator 4 is fixed to one end of the pretensioning tube 3. The driving member includes a polymer rod capable of plastic deformation and is placed in the pretensioning tube 3 to form an actuating end 81 close to the gas generator 4 and an ejection end 82 close to the other end of the pretensioning tube 3. The gear 22 is connected to the reel 21 for winding the seat belt. When the gas generator 4 is actuated, it pushes the driving member to engage with the gear 22, thereby driving the reel 21 to rotate and rewind the seat belt.

[0038] The driving member is made of thermoplastic material. An annular groove 10 is provided on the outer periphery of the actuating end 81 . The sealing member 9 is nested in the annular groove 10 and abuts against the inner wall of the preload tube 3 . The sealing member 9 is made of thermosetting material.

[0039] By opening an annular groove 10 on the outer periphery of the actuating end 81, the sealing member 9 is installed in the annular groove 10. The installation operation of the sealing member 9 is relatively convenient, and at the same time, the sealing between the driving member and the pre-tightening tube 3 can be ensured. When the gas generator 4 is actuated, high-pressure and high-temperature gas is generated to enter the pre-tightening tube 3. The gas pushes the driving member to move. The sealing member 9 moves synchronously with the driving member to always maintain the sealing between the actuating end 81 and the pre-tightening tube 3. After the driving member is discharged through the pre-tightening tube 3, it engages with the gear 22. When the driving member moves, it drives the gear 22 to rotate, and the gear 22 drives the reel 21 to rotate to reel the seat belt.

[0040] It should be noted that the seal 9 is made of thermosetting material, which reduces the melting phenomenon caused by the heat generated by the high-pressure gas in the preload tube 3. The thermosetting material can fit tightly with the annular groove 10 of the actuating end 81 and the inner wall of the preload tube 3 to form a reliable sealing effect. The explosion of the gas generator 4 will generate high temperature. Thermosetting material has good heat resistance and can withstand such a high temperature environment without deformation, softening or performance degradation. It ensures that the seal 9 can still play a good sealing role under high temperature conditions and will not lose its sealing function due to temperature increase.

[0041] like Figure 1-Figure 5As shown, in some embodiments, the actuating end 81 is provided with a protective member 12, and the protective member 12 has a protective portion 121 that covers the entire end surface of the actuating end 81. By providing the protective member 12 at the actuating end 81, the protective portion 121 covers the entire end surface of the actuating end 81. When the gas generator 4 is detonated, due to the presence of the protective portion 121, the high-temperature gas will first impact the protective portion 121. The protective portion 121 transmits the impact force to the driving member, which then causes the driving member to move. The protective portion 121 can protect the actuating end 81 and prevent the actuating end 81 from being directly impacted by the high-temperature gas.

[0042] like Figure 1-Figure 5 As shown, in some embodiments, a mounting slot 11 is formed on the end surface of the actuating end 81, and the protective member 12 also includes a mounting portion 122 connected to the protective portion 121, and the mounting portion 122 is fixed in the mounting slot 11. By opening the mounting slot 11 on the end surface of the actuating end 81, the mounting portion 122 of the protective member 12 is fixed in the mounting slot 11, thereby achieving a fixed connection between the protective member 12 and the actuating end 81, which can avoid separation between the protective member 12 and the actuating end 81 and ensure that the protective member 12 always has the effect of protecting the actuating end 81.

[0043] It should be noted that, in other embodiments, the protective member 12 may also be arranged to cover the actuating end 81 , and may be arranged according to actual conditions.

[0044] like Figure 1-Figure 5 As shown, in some embodiments, the actuating end 81 protrudes radially outward compared to the ejection end 82, and a stop structure is provided on the preload tube 3. The stop structure is configured to allow the ejection end 82 to pass through but prevent the actuating end 81 from passing through. The outer diameter of the actuating end 81 is larger than the outer diameter of the ejection end 82. A stop structure is provided inside the preload tube 3. When the driving member moves a certain distance and the actuating end 81 reaches the stop structure position, the actuating end 81 protrudes radially outward and its outer dimensions are larger than the pass-through dimension of the stop structure. The stop structure will block the actuating end 81, preventing the actuating end 81 from continuing to pass through, thereby preventing the driving member from completely escaping from the preload tube 3 and avoiding the risk of parts splashing.

[0045] It should be noted that if Figure 10 As shown, the cross section of the actuating end 81 is a radially symmetrical figure. The cross section of the actuating end 81 can be circular, elliptical, tooth-shaped or polygonal, and can be designed according to actual conditions.

[0046] like Figure 1-Figure 7As shown, in some embodiments, the pretensioning device further includes a guide member 6, which is arranged at the other end of the pretensioning tube 3, and includes a guide bevel 61 placed outside the pretensioning tube 3 and a stop portion 62 extending into the interior of the pretensioning tube 3, the guide bevel 61 is used to guide the driving member to engage with the gear 22, and the stop portion 62 is embedded between the outer periphery of the ejection end 82 and the inner wall of the pretensioning tube 3, and is configured as the stop structure. By arranging a guide member 6 at the other end of the preload tube 3, when the driving member is discharged from the preload tube 3, the guide slope 61 of the guide member 6 can guide the driving member, so that the driving member moves along a specific direction, thereby facilitating the driving member to engage with the gear 22 and drive the gear 22 to rotate. The guide member 6 also includes a stop portion 62 extending into the preload tube 3. The stop portion 62 forms a stop structure in the preload tube 3. The ejection end 82 can pass through the space between the stop portion 62 and the inner wall of the preload tube 3, while the actuating end 81 cannot pass through the space between the stop portion 62 and the inner wall of the preload tube 3, which can avoid separation between the actuating end 81 and the preload tube 3.

[0047] like Figure 1-Figure 7 As shown, in some embodiments, the port at the other end of the preload tube 3 partially extends outward to form an extension portion 31, and the guide member 6 is fixed to the extension portion 31. The bottom of one end of the preload tube 3 near the guide member 6 extends outward to form the extension portion 31. The guide member 6 can be fixed to the extension portion 31 by a screw or other mechanism to achieve a fixed connection between the guide member 6 and the preload tube 3, ensuring that the guide member 6 is always fixed relative to the preload tube 3.

[0048] like Figure 6-Figure 9 As shown, the stop structure has multiple configurations. The following lists several stop structures in different implementations:

[0049] In some embodiments, the retaining structure includes a plurality of hooks 13 provided at the other end of the preload tube 3, the hooks 13 extending radially inwardly of the preload tube 3, and the distance between the hooks 13 and the inner wall of the preload tube 3 or the corresponding hook 13 being greater than the outer diameter of the ejection end 82 and smaller than the outer diameter of the actuating end 81. In this embodiment, by providing a plurality of hooks 13 at the end of the preload tube 3, the ejection end 82 can pass through the space between the hooks 13 and the inner wall of the preload tube 3, while the actuating end 81 cannot pass through the space between the hooks 13 and the inner wall of the preload tube 3. The hooks 13 block and limit the actuating end 81, preventing separation between the actuating end 81 and the preload tube 3.

[0050] In other embodiments, the retaining structure includes a constricted portion 14 formed by an inward depression near the other end of the preload tube 3. The inner diameter of the constricted portion 14 is larger than the outer diameter of the ejection end 82 and smaller than the outer diameter of the actuation end 81. In this embodiment, the constricted portion 14 is formed by constricting the portion of the preload tube 3 near the other end inward. The ejection end 82 can pass through the constricted portion 14, while the actuation end 81 cannot. The constricted portion 14 blocks and limits the actuation end 81, preventing separation between the actuation end 81 and the preload tube 3.

[0051] In some other embodiments, the retaining structure includes a constricted portion 15 provided at the other end of the preload tube 3. The inner diameter of the constricted portion 15 gradually decreases as it moves away from the other end of the preload tube 3. The inner diameter of the constricted portion 15 is larger than the outer diameter of the ejection end 82 and smaller than the outer diameter of the actuation end 81. In this embodiment, by providing the constricted portion 15 at the other end of the preload tube 3, the inner diameter of the constricted portion 15 gradually decreases as it approaches the guide member 6. This allows the ejection end 82 to pass through the constricted portion 15, while the actuation end 81 cannot. The constricted portion 15 blocks and limits the actuation end 81, preventing separation between the actuation end 81 and the preload tube 3.

[0052] like Figure 11 As shown, in some embodiments, the pretensioning device further includes a housing 5. After being discharged from the pretensioning pipe 3, the driving member moves along the inner wall of the housing 5, driving the gear 22 to rotate. By providing the housing 5, the driving member moves within the housing 5, which can limit the range of movement of the driving member and prevent the driving member from colliding with other components.

[0053] See also Figures 1-11 Based on the same inventive concept, an embodiment of this specification provides a pretensioning retractor, comprising a frame 1, a reel 21 and a pretensioning device as described above, wherein the reel 21 is rotatably mounted on the frame 1, the gear 22 is mounted on the end of the reel 21, and the pretensioning tube 3 is mounted on the frame 1.

[0054] During implementation, by adopting the above-mentioned pre-tensioning device to reel in the safety belt, the sealing member 9 can remain unchanged under high-temperature gas, thereby ensuring the sealing effect between the driving member and the pre-tensioning tube 3, avoiding gas leakage, and ensuring the reeling effect of the safety belt.

[0055] 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.

[0056] 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 pretensioning device, comprising a gear (22), a pretensioning tube (3), a gas generator (4), a driving member (7) and a sealing member (9), wherein the gas generator (4) is fixed to one end of the pretensioning tube (3), the driving member (7) comprises a polymer rod capable of plastic deformation, is placed in the pretensioning tube (3) and is formed with an actuating end (81) close to the gas generator (4) and an ejection end (82) close to the other end of the pretensioning tube (3), the gear (22) is connected to a reel (21) for winding a seat belt, wherein: When the gas generator (4) is actuated, it pushes the driving member (7) to engage with the gear (22), thereby driving the reel (21) to rotate and rewind the safety belt, characterized in that: The driving member (7) is made of thermoplastic material, an annular groove (10) is provided on the outer periphery of the actuating end (81), the sealing member (9) is nested in the annular groove (10) and abuts against the inner wall of the preload tube (3), and the sealing member (9) is made of thermosetting material.

2. The pretensioning device according to claim 1, characterized in that: The actuating end (81) is provided with a protective member (12), and the protective member (12) has a protective portion (121) covering the entire end surface of the actuating end (81).

3. The pretensioning device according to claim 2, characterized in that: A mounting slot (11) is formed on the end surface of the actuating end (81), and the protective member (12) further comprises a mounting portion (122) connected to the protective portion (121), and the mounting portion (122) is fixed in the mounting slot (11).

4. The pretensioning device according to any one of claims 1 to 3, characterized in that: The actuating end (81) protrudes radially outward compared to the ejection end (82), and a stop structure is provided on the preload tube (3), wherein the stop structure is configured to allow the ejection end (82) to pass through but prevent the actuating end (81) from passing through.

5. The pretensioning device according to claim 4, characterized in that: The pre-tensioning device further comprises a guide member (6), which is arranged at the other end of the pre-tensioning tube (3) and comprises a guide bevel (61) disposed outside the pre-tensioning tube (3) and a stopper (62) extending into the interior of the pre-tensioning tube (3), wherein the guide bevel (61) is used to guide the driving member (7) to engage with the gear (22), and the stopper (62) is embedded between the outer periphery of the ejection end (82) and the inner wall of the pre-tensioning tube (3), and is configured as the stopper structure.

6. The pretensioning device according to claim 5, characterized in that: The port at the other end of the pre-tightening tube (3) partially extends outward to form an extension portion (31), and the guide member (6) is fixed on the extension portion (31).

7. The pretensioning device according to claim 4, characterized in that: The stopping structure comprises a plurality of hooks (13) provided at the other end of the preload tube (3), the hooks (13) extending radially inwardly of the preload tube (3), and a distance between the hooks (13) and the inner wall of the preload tube (3) or the corresponding hooks (13) being greater than the outer diameter of the ejection end (82) and smaller than the outer diameter of the actuating end (81); Alternatively, the stop structure includes a constricted portion (14), and the constricted portion (14) is formed by being recessed inward near the other end of the preload tube (3), and the inner diameter of the constricted portion (14) is larger than the outer diameter of the ejection end (82) and smaller than the outer diameter of the actuating end (81); Alternatively, the stopping structure includes a contraction portion (15) provided at the other end of the preload tube (3), wherein the inner diameter of the contraction portion (15) gradually decreases in a direction away from the other end of the preload tube (3), and the inner diameter of the contraction portion (15) is larger than the outer diameter of the ejection end (82) and smaller than the outer diameter of the actuating end (81).

8. The pretensioning device according to claim 1, characterized in that: The pre-tensioning device further comprises a housing (5), and the driving member (7) is discharged through the pre-tensioning pipe (3) and moves along the inner wall of the housing (5), thereby driving the gear (22) to rotate.

9. A pre-tensioning retractor, characterized in that: The invention comprises a frame (1), a reel (21) and a pretensioning device according to any one of claims 1 to 8, wherein the reel (21) is rotatably mounted on the frame (1), the gear (22) is mounted on the end of the reel (21), and the pretensioning tube (3) is mounted on the frame (1).

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