A pipeline type pretensioner

Abstract

The application discloses a pipeline type pre-tightener, which comprises a pipe body, a generator, a piston and a steel wire support, the generator is arranged in the inner cavity of the first end of the pipe body, the piston is arranged in the inner cavity of the second end of the pipe body, a channel is arranged in the pipe wall of the pipe body, the channel is communicated with the inner cavity of the second end of the pipe body through a first communication hole, the piston is located on the side of the first communication hole close to the generator, the first end of the steel wire support is connected with the piston, and the second end is located outside the pipe body. The whole pre-tightener is in a pipeline type, has a simple structure and a small appearance, is suitable for special installation position requirements, especially tubular structure position installation requirements, and solves the problem of installation limitation conditions; a secondary combustion chamber is arranged, when the air pressure reaches a predetermined value, the pressure release port is forced to open, the gas is rapidly discharged through the pressure release port and the channel, and then does work on the piston, pushes the piston to move to the side of the generator, thereby pulls the steel wire support to move, and the effect of tightening the occupant's belt is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle engineering, in particular to a pipeline type pretensioner. BACKGROUND

[0002] In a dual pretensioning safety belt occupant protection system, the function of the pretensioning device is to raise the force value of the occupant's latch position and the belt position as early as possible during a collision, reduce the forward displacement of the occupant's pelvic position, thereby reducing the displacement of the occupant's chest during the collision impact process, and minimizing injury.

[0003] As shown in Figure 4 , in the design of a conventional pretensioning device, the generator 4 and the wire support 7 are placed on the same side of the product. During operation, the generator 4 generates gas, which directly pushes the internal piston on that side to work, and the piston pulls the wire support 7 to move, thereby achieving the function of pretensioning. The disadvantage of such a design is that the generator protrudes obliquely outward, resulting in a larger volume on that side of the pretensioning device, which requires a larger installation location. If the installation location is special and the installation space is narrow and elongated, the existing pretensioning device is difficult to meet the installation requirements. Therefore, there is an urgent need for a new type of pretensioning device to solve the installation requirements of special locations or spaces, especially tubular locations or spaces. SUMMARY

[0004] To this end, the present application provides a pipeline type pretensioner to solve the above technical problems.

[0005] In order to achieve the above purpose, the present application provides the following technical scheme:

[0006] A pipeline type pretensioner, comprising a pipe body, a generator, a piston and a wire support, the generator is arranged in the inner cavity of the first end of the pipe body, the piston is arranged in the inner cavity of the second end of the pipe body, the pipe wall of the pipe body is provided with a channel, the channel is communicated with the inner cavity of the second end of the pipe body through a first communication hole, the piston is located on the side of the first communication hole close to the generator, the first end of the wire support is connected with the piston, and the second end is located outside the pipe body.

[0007] Further, the pipeline type pretensioner further comprises a secondary combustion chamber, the secondary combustion chamber is arranged in the inner cavity of the first end of the pipe body and communicated with the gas outlet of the generator, and a pressure release port with a constant pressure opening is arranged between the secondary combustion chamber and the channel.

[0008] Further, the pipe body comprises an inner pipe and an outer pipe, the outer pipe is sleeved outside the inner pipe and has an annular space between the pipe walls to form the channel, and sealing structures are arranged at both ends of the annular space.

[0009] Further, the side wall of the secondary combustion chamber is provided with a thin wall structure to form the pressure release port, and the side wall of the inner tube is provided with the first communication hole and the second communication hole, and the second communication hole corresponds to the position of the thin wall structure.

[0010] Further, the pipeline type pretensioner further comprises a first pressure cap fixed to the first end of the inner tube, and the first end of the outer tube and the first end of the generator abut against the first pressure cap.

[0011] Further, the pipeline type pretensioner further comprises a second pressure cap fixed to the second end of the inner tube, and the middle part of the second pressure cap is provided with a through hole, and the first end of the steel wire support is connected with the piston after passing through the through hole.

[0012] Further, the first end and the second end of the inner tube are both provided with sealing structures, the sealing structure of the first end is located on the side of the first communication hole away from the second communication hole, and the sealing structure of the second end is located on the side of the second communication hole away from the first communication hole.

[0013] Further, the second end of the generator is provided with a gas outlet, the first end of the secondary combustion chamber is provided with an open port, and the rest is closed, the second end of the generator is communicated with the first end of the secondary combustion chamber, the first end of the inner tube is provided with a limiting structure in the inner cavity, and the second end of the secondary combustion chamber abuts against the limiting structure.

[0014] Further, the first end of the second pressure cap is fixed in the second end of the inner tube, and the first end of the second pressure cap is provided with a sealing structure to seal the inner wall of the inner tube; and the through hole is provided with a sealing structure to seal the steel wire support.

[0015] Further, the connecting position of the second end of the generator and the first end of the secondary combustion chamber is provided with a sealing structure to seal the connecting position and the gap between the first end of the secondary combustion chamber and the inner tube, and the outer side of the second end of the secondary combustion chamber is provided with a sealing structure to seal the inner wall of the inner tube.

[0016] The present application has the following advantages:

[0017] 1. The generator is arranged in the pipe body, the steel wire support is arranged at the other end of the pipe body, and there is no protrusion of the traditional pretensioning device, the whole end piece pretensioner is in a pipeline type, the outer shape structure is simple, the appearance is small and exquisite, and the special installation position requirement can be met, especially the tubular structure position installation requirement, and the installation limitation condition problem is solved.

[0018] 2, provided with secondary combustion chamber, generator receives ignition signal, a large number of gas, gas into the secondary combustion chamber for secondary combustion, prevent incomplete combustion, when the air pressure reaches the predetermined value, forced pressure release opening, gas quickly through the pressure release opening, second communication hole, channel and first communication hole after the piston work, push the piston to the generator side, so as to pull the steel wire support movement, steel wire support connection passenger belt, so as to achieve the effect of tightening the passenger belt. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only exemplary, and for those skilled in the art, other drawings can be derived from the provided drawings without creative labor.

[0020] The structure, proportion, size and the like shown in the specification are only used to cooperate with the content disclosed in the specification, so that those skilled in the art can understand and read, and are not used to limit the implementation conditions of the present application, so they do not have technical significance. Any modification of structure, change of proportion relationship or adjustment of size, without affecting the effect and purpose of the present application, should still fall within the scope of the technical content disclosed by the present application.

[0021] Figure 1 A sectional view of a pipeline type pretensioner provided for an embodiment of the present application;

[0022] Figure 2 A perspective view of the pipeline type pretensioner provided for an embodiment of the present application;

[0023] Figure 3 A Figure 1 Enlarged view of A in

[0024] Figure 4 A schematic view of a conventional pretensioning device in the background art.

[0025] In the figure: 1-pipe body, 11-inner tube, 12-outer tube, 13-channel, 111-first communication hole, 112-second communication hole, 113-limit ring, 114-piston cavity, 2-first pressure cap, 3-second pressure cap, 4-generator, 5-secondary combustion chamber, 51-pressure release opening, 6-piston, 7-steel wire support. DETAILED DESCRIPTION

[0026] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity of description and are not intended to limit the scope of the invention. Any changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0028] like Figures 1 to 3 As shown, this embodiment provides a pipeline type pretensioner, including a pipe body 1, a first pressure cap 2, a second pressure cap 3, a generator 4, a secondary combustion chamber 5, a piston 6, a wire support 7, and several sealing rings.

[0029] The tube body 1 is generally a straight tube, but it can also be a tube with a curved section (installed in a special curved narrow space; because the piston 6 moves inside the tube body 1, the position of the piston 6 needs to be straight, such as the piston chamber 114 being a cylindrical straight cavity). The generator 4, secondary combustion chamber 5, and first pressure cap 2 are installed at the first end of the tube body 1, and the piston 6, wire support 7, and second pressure cap 3 are installed at the second end. A channel 13 is provided in the tube wall of the tube body 1. This channel 13 can be a hole or an annular space, and it connects the secondary combustion chamber 5 and the piston chamber 114. The piston 6 is installed at the second end of the tube body 1; therefore, the inner cavity at the second end is actually the piston chamber 114. A first connecting hole 111 connecting the piston chamber 114 and the channel 13 is provided at the second end of the tube body 1. In this embodiment, the tube body 1 includes an inner tube 11 and an outer tube 12. The outer tube 12 is sleeved outside the inner tube 11, and an annular space exists between their tube walls to form the channel 13. The inner tube 11 has a first connecting hole 111 near one end and a second connecting hole 112 near the other end. The number of the first connecting hole 111 or the second connecting hole 112 is not limited to one. Both the first and second ends of the inner tube 11 have sealing grooves. The sealing groove at the first end is located on the side of the first connecting hole 111 away from the second connecting hole 112, and the sealing groove at the second end is located on the side of the second connecting hole 112 away from the first connecting hole 111. A sealing ring is installed in the sealing groove. A concave limiting ring 113 is provided in the inner cavity of the first end of the inner tube 11 to restrict the movement of the secondary combustion chamber 5 towards the piston 6. Generally, the tube body 1 is made of steel pipe resistant to a certain pressure, but high-strength engineering plastic pipe can also be used.

[0030] The first pressure cap 2 is in the shape of a short cylinder, has a two-step hole in the middle, a pin hole at the first end, and a large hole at the second end. The first end of the inner tube 11 has external threads, and the first pressure cap 2 is fixed to the inner tube 11 by threads. The first end of the outer tube 12 and the first end of the generator 4 abut the first pressure cap 2.

[0031] The second pressure cap 3 is in the shape of a short stepped shaft, has a small shaft at the first end and a large shaft at the second end. The small shaft has external threads, and the second end of the inner tube 11 has internal threads. The second pressure cap 3 is fixed to the inner tube 11 by threads, and the second end of the outer tube 12 abuts the second pressure cap 3. The small shaft of the second pressure cap 3 needs to be sealed with the inner tube 11 to form a piston cavity 114 at the second end of the inner tube 11. Therefore, the first end of the second pressure cap 3 has a sealing groove, and the sealing groove has a sealing ring to seal the inner wall of the inner tube 11. The middle of the second pressure cap 3 has a perforation for the steel wire support 7, and the perforation has a sealing groove with a sealing ring to seal the gap between the steel wire support 7 and the perforation.

[0032] The generator 4 is a conventional device installed in the inner cavity of the first end of the inner tube 11. The first end of the generator 4 abuts the first pressure cap 2 to prevent the generator 4 from coming out of the inner tube 11. The second end of the generator 4 has a gas outlet for the gas generated by ignition to be discharged into the secondary combustion chamber 5.

[0033] The secondary combustion chamber 5 is arranged in the inner cavity of the first end of the tube body 1 and communicates with the gas outlet of the generator 4. The secondary combustion chamber 5 is a semi-enclosed cylindrical structure with a shell, and the first end is open to connect with the second end of the generator 4, forming a sealed structure. A sealing groove is naturally formed at the connection between the generator 4 and the secondary combustion chamber 5, and a sealing ring is fitted in the sealing groove. The sealing ring can seal the connection between the generator 4 and the secondary combustion chamber 5, and can also seal the gap between the first end of the secondary combustion chamber 5 and the inner tube 11. The second end of the secondary combustion chamber 5 has a sealing groove with a sealing ring fitted in it. The sealing ring is used to seal the gap between the second end of the secondary combustion chamber 5 and the inner tube 11. The middle section of the secondary combustion chamber 5 has one or more thin-walled structures to form pressure release ports 51. The thin-walled structures correspond to the positions of the second communication holes 112 (i.e., the thin-walled structures overlap the second communication holes 112 in the radial direction). When the pressure in the secondary combustion chamber 5 reaches a predetermined value, the thin-walled structures break, allowing communication with the passage 13 through the second communication holes 112. The second end of the secondary combustion chamber 5 abuts the limiting ring 113, and the position of the generator 4 and the secondary combustion chamber 5 in the inner tube 11 is fixed under the limiting of the limiting ring 113 and the first pressure cap 2.

[0034] The piston 6 is slidingly and sealingly arranged in the second end of the inner tube 11, and the distance between the piston 6 and the second end of the inner tube 11 is slightly greater than the distance between the first communication hole 111 and the second end of the inner tube 11, i.e. the piston 6 is located on the side of the first communication hole 111 close to the generator 4, so that the piston 6 can move towards the generator 4 when it is pushed by the gas.

[0035] The first end of the steel wire holder 7 is connected with the piston 6 without damaging the air tightness of the piston 6, and the second end is connected with the passenger belt after passing through the hole of the second pressure cap 3.

[0036] In the pipeline type pretensioner provided by the embodiment, the generator 4 is arranged at one end of the pipe body 1, the steel wire holder 7 is arranged at the other end of the pipe body 1, and the generator 4 and the steel wire holder 7 are opposite to each other; the secondary combustion chamber 5 is arranged at the second end (also referred to as the front side, which refers to the end with the gas outlet) of the generator 4, and a pressure release port 51 is arranged between the secondary combustion chamber 5 and the channel 13; after receiving the ignition signal, the generator 4 generates a large amount of gas, which enters the secondary combustion chamber 5; when the pressure in the secondary combustion chamber 5 reaches a predetermined value, the pressure release port 51 is passively opened, and the gas enters the channel 13 through the pressure release port 51 and the second communication hole 112; the gas is rapidly transported to the piston cavity 114 through the channel 13 arranged in the wall of the pipe body 1, and after entering the piston cavity 114 through the first communication hole 111, the piston 6 is pushed to move; the piston 6 pulls the steel wire holder 7 to move, and the steel wire holder 7 is connected with the passenger belt, so that the function of tightening the passenger belt is achieved.

[0037] Although the present application has been described in detail by the general description and specific embodiments above, some modifications or improvements can be made on the basis of the present application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the present application are within the scope of the present application.

Claims

1. A tube type pretensioner characterized by, The pipeline pre-tightener comprises a pipe body, a generator, a piston, a steel wire support and a secondary combustion chamber, the generator is arranged in the inner cavity of the first end of the pipe body, the piston is arranged in the inner cavity of the second end of the pipe body, a channel is arranged in the pipe wall of the pipe body, the channel is communicated with the inner cavity of the second end of the pipe body through a first communication hole, the piston is located on the side of the first communication hole close to the generator, the first end of the steel wire support is connected with the piston, and the second end is located outside the pipe body, the secondary combustion chamber is arranged in the inner cavity of the first end of the pipe body and communicated with the gas outlet of the generator, and a pressure release port with a constant pressure opening is arranged between the secondary combustion chamber and the channel.

2. The in-line pretensioner of claim 1, wherein The pipe body comprises an inner pipe and an outer pipe, the outer pipe is sleeved outside the inner pipe, and an annular space is formed between the pipe walls of the inner pipe and the outer pipe to form the channel, and sealing structures are arranged at both ends of the annular space.

3. The in-line pretensioner of claim 2, wherein, The side wall of the secondary combustion chamber is provided with a thin wall structure to form the pressure release port, the side wall of the inner pipe is provided with the first communication hole and a second communication hole, and the second communication hole corresponds to the position of the thin wall structure.

4. The in-line pretensioner of claim 2, wherein, The pipeline pre-tightener further comprises a first pressure cap, the first pressure cap is fixed outside the first end of the inner pipe, and the first end of the outer pipe and the first end of the generator are in abutment with the first pressure cap.

5. The in-line pretensioner of claim 2, wherein, The pipeline pre-tightener further comprises a second pressure cap, the second pressure cap is fixed at the second end of the inner pipe, a through hole is arranged in the middle of the second pressure cap, and the first end of the steel wire support is connected with the piston after penetrating through the through hole.

6. The in-line pretensioner of claim 3, wherein Sealing structures are arranged outside the first end and the second end of the inner pipe, the sealing structure at the first end is located on the side of the first communication hole away from the second communication hole, and the sealing structure at the second end is located on the side of the second communication hole away from the first communication hole.

7. The in-line pretensioner of claim 4, wherein The second end of the generator is provided with a gas outlet, the first end of the secondary combustion chamber is provided with an open end, the second end of the generator is communicated with the first end of the secondary combustion chamber, a limiting structure is arranged in the inner cavity of the first end of the inner pipe, and the second end of the secondary combustion chamber is in abutment with the limiting structure.

8. The in-line pretensioner of claim 5, wherein, The first end of the second pressure cap is fixed in the second end of the inner pipe, the first end of the second pressure cap is provided with a sealing structure to seal the inner wall of the inner pipe, and a sealing structure is arranged in the through hole to seal the steel wire support.

9. The in-line pretensioner of claim 7, wherein, A sealing structure is arranged at the connection between the second end of the generator and the first end of the secondary combustion chamber to seal the connection and the gap between the first end of the secondary combustion chamber and the inner pipe, and a sealing structure is arranged outside the second end of the secondary combustion chamber to seal the inner wall of the inner pipe.

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