Seat belt retractor

Abstract

The present invention provides a seat belt retractor. The seat belt retractor comprises a spool that winds a seat belt onto the side surface thereof by rotating in a winding direction; and a locking assembly provided at a first axial end of the spool and locking the rotation of the spool in an unwinding direction under a predetermined condition. The spool comprises an insert and an overmolded member that at least partially covers the insert. The first axial end of the spool comprises a first axially inner end of the insert and a first axially outer end of the overmolded member, wherein the first axially outer end comprises a first cavity and a second cavity, the first axially inner end is positioned within the first cavity, and a portion of a pawl in the locking assembly is positioned within the second cavity. The first cavity and the second cavity at least partially overlap in an axial direction, so that when the pawl is pivoted from a first position to a second position in the second cavity, the pawl abuts against the first axially inner end in a circumferential direction of the spool.

Description

Seat belt retractor Technical Field

[0001] This invention relates to safety devices for vehicles, and more specifically, to seatbelt retraction devices. Background Technology

[0002] As a safety device in vehicles, seat belts are used to restrain occupants during a collision and prevent secondary impacts between occupants and the steering wheel, dashboard, etc., or to prevent occupants from being ejected from the vehicle and suffering injury or death. Typically, a seat belt retractor is installed in the limited space of the vehicle seat to store the seat belt, and the seat belt is wound up on the retractor's spindle. Occupants can insert the latch attached to the seat belt into a buckle fixed to the vehicle body structure to restrain themselves in the seat; and occupants can release the latch from the buckle to allow them to leave the seat. Nowadays, seat belt retractors have a pre-tensioning function. Specifically, during or even before a collision, the pre-tensioner winds up the seat belt to enhance restraint. This pre-tensioner can act on the spindle, causing the spindle to rotate in the winding direction to tighten the seat belt. Therefore, the spindle requires high strength.

[0003] The goal is to provide a seatbelt retraction device that is both strong and compact. Summary of the Invention

[0004] The purpose of this invention is to provide a seat belt rewinding device that is strong and compact, particularly a seat belt rewinding device whose spindle has high strength while having a small size.

[0005] This invention provides a seatbelt retraction device, which includes

[0006] A spindle that winds the seatbelt onto its side by rotating in the winding direction;

[0007] A locking assembly is disposed at the first shaft end of the mandrel and, under predetermined conditions, locks the rotation of the mandrel in the unwinding direction;

[0008] in,

[0009] The mandrel includes an insert and a cover that at least partially covers the insert, and,

[0010] The first shaft end of the mandrel includes a first inner shaft end of the insert and a first outer shaft end of the cover. The first outer shaft end includes a first chamber and a second chamber. The first inner shaft end is positioned in the first chamber, and a portion of the pawl in the locking assembly is positioned in the second chamber.

[0011] The first chamber and the second chamber overlap at least partially in the axial direction, such that when the pawl pivots from the first position to the second position in the second chamber, it abuts against the first inner shaft end in the circumferential direction of the mandrel.

[0012] According to an embodiment of the present invention, the first inner shaft end of the insert has a first branch and a second branch that are at least partially separated by the missing portion, and the second chamber is positioned in the missing portion such that the pawl abuts against both the first branch and the second branch when in the second position.

[0013] According to an embodiment of the present invention, the pawl includes a first abutment and a second abutment disposed on opposite sides in its pivoting direction, and the second chamber shares a wall defining the chamber space with the first chamber.

[0014] According to an embodiment of the present invention, the first outer shaft end of the cover has a first shaft segment and a second shaft segment distributed sequentially in the axial direction, and both the first chamber and the second chamber are disposed in the first shaft segment, and the teeth of the pawl protrude radially from the circumferential side of the first shaft segment.

[0015] According to an embodiment of the present invention, the insert includes a first insert plate and a second insert plate arranged overlapping in the thickness direction, the first insert plate including a first limiting structure, the second insert plate including a second limiting structure, and the first limiting structure and the second limiting structure cooperating with each other to limit the position of the first insert plate and the second insert plate relative to each other in the radial and / or axial directions.

[0016] According to an embodiment of the present invention, one of the first limiting structure and the second limiting structure is configured as a slot, and the other is configured as a tab, and the tab is positioned in the slot;

[0017] And / or,

[0018] Each of the first inner panel and the second inner panel has two bends at the first shaft end, the two bends of the first inner panel and the second inner panel are spaced apart in the width direction, and the corresponding bends of the first inner panel and the second inner panel are aligned in the width direction.

[0019] According to an embodiment of the present invention, the second shaft end of the mandrel includes a second inner shaft end of the insert and a second outer shaft end of the cover, wherein the second inner shaft end protrudes axially from the end face of the second outer shaft end for connection with the pretensioner.

[0020] According to an embodiment of the present invention, the mandrel includes a narrower intermediate section located between the first shaft end and the second shaft end, and the intermediate section is used to wind the webbing of the seat belt.

[0021] According to an embodiment of the present invention, an elongated hole is provided on the middle section of the first inner panel and / or the second inner panel.

[0022] According to an embodiment of the present invention, the insert is made of a stronger material than the cover. Attached Figure Description

[0023] The features, advantages, and technical effects of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. In the drawings, the same symbols denote the same elements, wherein:

[0024] Figure 1 schematically shows an exploded view of a seatbelt retractor according to an embodiment of the present invention.

[0025] Figure 2 schematically shows some components of the seat belt retractor according to an embodiment of the present invention.

[0026] Figure 3 schematically shows another component of the seatbelt retractor according to an embodiment of the present invention.

[0027] Figure 4 is a schematic diagram of the component shown in Figure 3 from another viewing angle.

[0028] Figure 5 schematically illustrates a component of a seatbelt retraction device according to an embodiment of the present invention.

[0029] Figures 6(a) and 6(b) schematically illustrate the working principle of some components in the seat belt retraction device. Detailed Implementation

[0030] The following describes specific embodiments of the seatbelt retraction device according to the present invention in conjunction with the accompanying drawings. The detailed description and drawings below are provided to exemplify the principles of the invention. The invention is not limited to the described preferred embodiments; the various embodiments described can be used individually or in any combination. The scope of protection of the invention is defined by the claims.

[0031] Furthermore, spatially related terms (such as "up," "down," "left," and "right") are used to describe the relative positional relationship between elements shown in the accompanying drawings and other elements. Therefore, spatially related terms can be applied to directions different from those shown in the accompanying drawings. Clearly, while all these spatially related terms refer to the directions shown in the accompanying drawings for ease of explanation, those skilled in the art will understand that directions different from those shown in the accompanying drawings can be used.

[0032] Figure 1 schematically shows an exploded view of a seatbelt retraction device according to an embodiment of the present invention. The seatbelt retraction device according to an embodiment of the present invention will be described below with reference to Figure 1.

[0033] As shown in Figure 1, the seatbelt retractor 1 includes a spindle 10, a pretensioner 20 located on one axial side of the spindle 10, and a locking assembly 30 and a force-applying assembly 40 located on the other axial side of the spindle 10. Furthermore, the seatbelt retractor 1 also includes a frame 50, which is to be fixed at a predetermined location in the vehicle, for example, to the seat cushion frame of the seat frame. The various components of the seatbelt retractor 1 will be described in detail below.

[0034] The spindle 10 is generally cylindrical and is positioned inside the frame 50. Specifically, as shown in Figure 1, the frame 50 includes two side plates arranged opposite each other in the left-right direction. The axial ends of the spindle 10 are respectively positioned on these two side plates of the frame 50 and are capable of rotating about their own central axis. In addition, one end of the seat belt webbing (not shown) along the length direction is fixed to the circumferential side of the spindle 10. When the spindle 10 rotates in the winding direction, the seat belt webbing is wound onto the spindle 10; conversely, when the spindle 10 rotates in the unwinding direction, the seat belt webbing is disengaged from the spindle 10. In this way, the occupant can adjust the wearing length of the seat belt.

[0035] The pretensioner 20 includes a micro gas generator 21, a transfer piston 22, a moving rod 23, and a tube 25 for receiving and guiding the moving rod 23. The transfer piston 22 transmits the driving force of the micro gas generator 21 to the moving rod 23. The micro gas generator 21 includes a gas generating agent and a housing (not shown) for containing the gas generating agent, as well as an ignition device and another housing (not shown) for containing the ignition device. The ignition device heats up when energized, thereby igniting the gas generating agent. The gas generating agent burns, instantaneously generating a high-pressure gas. Simultaneously, the high-pressure gas generated by the gas generating agent forces a sufficiently large gas pressure within the housing containing the gas generating agent, causing the housing to expand and deform until it breaks. Next, high-temperature, high-pressure gas flowing from the containment section that originally held the gas generator is supplied into the tube 25. Specifically, high-temperature, high-pressure gas is supplied into the tube 25 from one end. The transmission piston 22 is positioned at that end of the tube 25, and after being subjected to the force applied by the high-temperature, high-pressure gas, this force is transmitted to the moving rod 23, causing the moving rod 23 to move along the tube 25. The pretensioner 20 also includes a rotating member 100, which is connected to the spindle 10 in a rotatable manner. An end cap 26 is fixed to one side of the frame 50 to accommodate the rotating member 100 and at least a portion of the moving rod 23 when engaged with the rotating member 100. The movement of the moving rod 23 along the tube 25 occurs, for example, in a vehicle emergency, and can be made of, for example, synthetic resin. The moving rod 23 moves to engage with the rotating member 100, thereby driving the rotating member 100 and thus driving the spindle 10 to rotate in the winding direction. That is, the seat belt device 1 has a pretensioning function.

[0036] The locking assembly 30 includes a cover 31 and an actuator 32 and an actuator 33 housed within the cover 31. Furthermore, the locking assembly 30 includes a pawl 34 disposed at the end face of the spindle 10. In an emergency, the actuator 33 actuates the actuator 32, causing the actuator 32 to engage with the pawl 34, thereby locking the rotation of the spindle 10 in the unwinding direction.

[0037] The force-applying assembly 40 includes a spring housing 41, a spring 42 disposed inside the housing 41, and a spring plate 43 for fixing the spring 42. The force-applying assembly 40 applies a rotational force in the winding direction to the spindle 10 by means of the force of the spring 42, for example, to adjust the length of the seat belt worn by the occupant.

[0038] Figure 2 schematically shows some components of a seatbelt retractor according to an embodiment of the present invention. Figure 3 schematically shows another portion of a seatbelt retractor according to an embodiment of the present invention. Figure 4 is a schematic diagram of the components shown in Figure 3 from another viewing angle. Figure 5 schematically shows one component of a seatbelt retractor according to an embodiment of the present invention. The seatbelt retractor according to an embodiment of the present invention will be described below with reference to Figures 2 to 5.

[0039] Figures 2 and 3 respectively show schematic diagrams of some components in an assembled or operational state of a seatbelt retractor according to an embodiment of the present invention. Specifically, Figure 2 schematically shows the pawl 34 of the locking assembly 30 mounted at the first shaft end of the spindle 10, specifically on the left end face of the spindle 10 in Figure 2, and the rotating member 100 of the pretensioner 20 mounted at the second shaft end of the spindle 10, specifically on the right end face of the spindle 10 in Figure 2. The spindle 10 has a generally cylindrical circumferential side surface for retracting the seatbelt webbing (not shown), which is wound onto the circumferential side surface when the spindle 10 rotates in the retracting direction. It should be noted that both the pawl 34 and the rotating member 100 are mounted on the spindle 10 in a manner that allows them to rotate together with the spindle 10. Furthermore, the pawl 34 is fixed to the spindle 10 via a pivot shaft, and therefore can also pivot relative to the spindle 10. The moving rod (not shown) of the pretensioner 20 engages with the rotating member 100. The moving rod moves and drives the rotating member 100, thereby driving the mandrel 10 to rotate in the winding direction to wind the seat belt webbing onto the mandrel 10. Next, the locking assembly 30 locks the rotation of the mandrel 10 in the unwinding direction, which will be described in more detail later with reference to Figures 6(a) and 6(b). That is, the locking assembly 30 locks the rotation of the mandrel 10 in the unwinding direction under predetermined conditions, which may be a predetermined time after the pretensioner 20 completes the pretensioning action, such as a few milliseconds.

[0040] Referring to Figures 2, 3, and 5, the mandrel 10 includes an insert 11 and a cover 12, the cover 12 at least partially covering the insert 11. The insert and cover of the present invention are described in detail below.

[0041] As shown in Figure 5, the length direction of the insert 11 is consistent with the axial direction of the spindle 10, and includes two opposite ends in the length direction, namely the first inner shaft end 111 and the second inner shaft end 112. Compared with other sections, the first inner shaft end 111 of the insert 11 has a larger cross-sectional area. Accordingly, as shown in Figures 3 and 4, the first inner shaft end 111 includes a first branch 111A, a second branch 111B, and a missing portion 111C that separates the two. As shown in Figures 3 and 4, in this embodiment, the missing portion 111C completely separates the first branch 111A and the second branch 111B. However, it should be noted that the missing portion 111C is mainly used to reserve space for the pawl 34 in the locking assembly 30 at the position of the first inner shaft end 111 of the insert 11. Therefore, the missing portion 111C is designed mainly based on the shape and / or size and / or position of the pawl 34. Thus, the missing portion 111C is not limited to completely separating the first branch and the second branch. In fact, the missing portion can be designed to at least partially separate the first branch and the second branch.

[0042] In one example, as shown in FIG. 5, the insert 11 may include a first insert plate 110 and a second insert plate 120, which are arranged overlapping in the thickness direction and aligned axially with the mandrel 10 to jointly define the aforementioned first inner shaft end 111 and second inner shaft end 112 of the insert 11. For example, the first insert plate 110 includes two bends 1111 at the first shaft end 111, which are spaced apart in the width direction of the first insert plate 110. Similarly, the second insert plate 120 also includes two bends (not fully shown) at the first inner shaft end 111, which are also spaced apart in the width direction of the second insert plate 120. Furthermore, the bent portion of the first inner panel 110 located on the front side in FIG. 5 and the bent portion of the second inner panel 120 located on the front side in FIG. 5 are aligned in the width direction of the inner member 11 to define the second branch 111B; the bent portion of the first inner panel 110 located on the rear side in FIG. 5 and the bent portion of the second inner panel 120 located on the rear side in FIG. 5 are aligned in the width direction of the inner member 11 to define the first branch 111A. It can be understood that in the above embodiment, the first inner member and the second inner member can be formed by cutting and bending the ends of the sheet metal. That is, each of the first inner member and the second inner member is a one-piece component. Of course, this is just an example, and the first inner member and the second inner member can also be components with different segments fixed together.

[0043] Furthermore, to define the relative position between the first inner panel 110 and the second inner panel 120, the first inner panel 110 includes a first limiting structure 1101, and the second inner panel 120 includes a second limiting structure 1201, which cooperate with each other. In one example, the first limiting structure 1101 can be configured as a pair of slots positioned at opposite edges of the first inner panel 110; in other words, the first limiting structure 1101 is configured as a pair of notches. The second limiting structure 1201 is configured as a pair of tabs, which are respectively positioned within the aforementioned pair of slots. During installation, the first inner plate 110 and the second inner plate 120 are overlapped in the thickness direction. Then, the second limiting structure 1201 in the form of a protrusion is aligned one-to-one with the first limiting structure 1101 in the form of a slot, and the protrusion is bent until the end of the protrusion abuts against the top surface of the first inner plate 110, as shown in FIG. 5. The protrusion has an enlarged end. When bent to the top surface of the first inner plate 110, the enlarged end of the protrusion will abut against the surface of the first inner plate 110 to prevent the first inner plate 110 and the second inner plate 120 from separating in the thickness direction. At the same time, the two axial sides of the protrusion abut against the two sides of the slot of the first inner plate 110 to prevent the first inner plate 110 and the second inner plate 120 from separating in the axial direction. In addition, a pair of protrusions clamp the first inner plate 110 in the width direction of the inner member 11. In this way, the relative positions of the first inner plate 110 and the second inner plate 120 in the axial and radial directions of the mandrel 10 are defined. Of course, this is merely an example, and the first and second limiting structures are not limited to the examples above. For instance, the first limiting structure can be configured as a protrusion, and correspondingly, the second limiting structure can be constructed as a slot, or configured as other types of limiting members. Furthermore, as an embodiment of the present invention, an elongated hole 1103 is provided on the middle section of the first inner plate 110 and the second inner plate 120 to reduce the overall weight of the inner plates.

[0044] Returning to Figures 2 and 3, as shown in Figures 2 and 3, the cover 12 includes a first outer shaft end 101, a second outer shaft end 102, and an intermediate section 103 located between them (i.e., the outer portion of the intermediate section of the mandrel). This intermediate section 103 is narrower than the two shaft ends and is used for winding the seat belt. The first outer shaft end 101 of the cover 12 has a first shaft segment 1011 and a second shaft segment 1012 distributed sequentially in the axial direction. The second shaft segment 1012 is located at the outermost end of the cover 12. To show the first inner shaft end 111 of the insert 11, a portion of the first outer shaft end 121 of the cover 12 is omitted in Figure 3 compared to Figure 2, and in particular, the second shaft segment 1012, which will be described later, is omitted.

[0045] As shown in Figures 2 and 3, the mandrel 10 includes a first shaft end (left end in the figure) and a second shaft end (right end in the figure) that are axially opposite to each other. The first shaft end of the mandrel 10 includes a first inner shaft end 111 of the insert 11 and a first outer shaft end 121 of the cover 12. The first outer shaft end 121 includes a first chamber 1211 (see Figures 6(a) and 6(b)) and a second chamber 1212 (see Figure 3). In one example, as shown in Figure 2, both the first chamber 1211 and the second chamber 1212 are disposed in the first shaft segment 1011; that is, different sections of the first shaft segment 1011 in the circumferential direction are respectively used for the first chamber 1211 and the second chamber 1212. Then, the second shaft segment 1012 is used to cover the end of the first shaft segment 1011 to close the end side of the first shaft segment 1011.

[0046] As shown in Figures 6(a) and 6(b), the first inner shaft end 111, particularly the first branch 111A and the second branch 111B of the first inner shaft end 111, is positioned within the first chamber 1211, and a portion of the pawl 34 in the locking assembly 30 is positioned within the second chamber 1212. Referring to Figure 3, the first chamber 1211 and the second chamber 1212 at least partially overlap axially in the mandrel 10, such that the pawl 34 abuts against the first inner shaft end 111 in the circumferential direction of the mandrel 10 when pivoting in the second chamber 1212 from the first position shown in Figure 6(a) to the second position shown in Figure 6(b). Specifically, as shown in Figure 6(a), in the first position, the pawl 34 is substantially completely contained within the second chamber 1212. As shown in Figure 6(b), when the pawl 34 pivots from the first position to the second position, the teeth of the pawl 34 protrude radially from the circumferential side of the first shaft segment 1011. At this time, the teeth of the pawl 34 protruding from the first shaft segment 1011 engage the ratchet (which can be mounted on the cover 31). The interaction between the ratchet and the pawl 34 locks the rotation of the pawl 34 and thus the spindle 10 in the winding direction. It is understood that during locking, the pawl 34 will exert a large force on the insert 11. Therefore, in the seatbelt retraction device of the present invention, the insert 11 is made of a stronger material than the cover 12. As an example, the cover can be made of plastic, and the insert can be made of metal. The metal insert is mainly used to support the pawl, while the plastic cover helps to reduce the overall weight of the spindle and achieve a smaller size.

[0047] In one embodiment of the present invention, the second chamber 1212 is positioned within the missing portion 111C. The pawl 34 includes a first abutment portion 341 and a second abutment portion 342 disposed on opposite sides in its pivoting direction. The second chamber 1212 shares a wall 1213 defining the chamber space with the first chamber 1211. That is, the pawl 34 is not in direct contact with the first inner shaft end 111, and a shared wall 1213 is provided between them. This shared wall 1213 is actually part of the covering member 12. In this embodiment, when the pawl 34 is in the second position shown in FIG. 6(b), its first abutment portion 341 and second abutment portion 342 abut against both the first branch portion 111A and the second branch portion 111B, respectively. It can be understood that the pawl abutting against the first inner shaft end in two positions ensures that the first inner shaft end of the insert is subjected to uniform force, which helps to improve the smoothness of the locking process and the service life of the insert.

[0048] Furthermore, as shown in Figures 2 and 3, the second shaft end of the mandrel 10 includes a second inner shaft end 112 of the insert 11 and a second outer shaft end 102 of the cover 12. The second inner shaft end 112 protrudes axially from the end face of the second outer shaft end 102 to connect with the pretensioner 30. Compared to the first inner shaft end 111, the second inner shaft end 112 of the insert 11 has a slender structure, which is beneficial for reducing the weight and volume of the insert and thus the mandrel.

[0049] As mentioned above, although exemplary embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the specific embodiments described above, and the scope of protection of the present invention should be defined by the claims and their equivalents.

Claims

1. A seatbelt retraction device (1), comprising: The spindle (10) winds the seat belt onto its side by rotating in the winding direction; A locking assembly (30) is disposed at the first shaft end of the mandrel (10) and, under predetermined conditions, locks the rotation of the mandrel (10) in the unwinding direction; Its features are, The mandrel (10) includes an insert (11) and a cover (12) that at least partially covers the insert (11), and, The first shaft end of the mandrel (10) includes a first inner shaft end (111) of the insert (11) and a first outer shaft end (121) of the cover (12). The first outer shaft end (121) includes a first chamber (1211) and a second chamber (1212). The first inner shaft end (111) is positioned within the first chamber (1211), and a portion of the pawl (34) in the locking assembly (30) is positioned within the second chamber (1212). The first chamber (1211) and the second chamber (1212) overlap at least partially in the axial direction, such that when the pawl (34) pivots from the first position to the second position in the second chamber (1212), it abuts against the first inner shaft end (111) in the circumferential direction of the mandrel (10).

2. The seat belt retraction device (1) according to claim 1, wherein, The first inner shaft end (111) of the insert (11) has a first branch (111A) and a second branch (111B) that are at least partially separated by the missing portion (111C), and the second chamber (1212) is positioned in the missing portion (111C) such that the pawl (34) abuts against both the first branch (111A) and the second branch (111B) in the second position.

3. The seatbelt retraction device (1) according to claim 2, wherein, The pawl (34) includes a first abutment (341) and a second abutment (342) disposed on opposite sides in its pivoting direction, and the second chamber (1212) shares a wall (1213) defining the chamber space with the first chamber (1211).

4. The seat belt retraction device (1) according to claim 3, wherein, The first outer shaft end (121) of the cover (12) has a first shaft segment (1011) and a second shaft segment (1012) distributed sequentially in the axial direction, and the first chamber (1211) and the second chamber (1212) are both disposed in the first shaft segment (1011), and the teeth of the pawl (34) protrude radially from the circumferential side of the first shaft segment (1011).

5. The seatbelt retraction device (1) according to claim 1, wherein, The insert (11) includes a first insert plate (110) and a second insert plate (120) arranged overlapping in the thickness direction. The first insert plate (110) includes a first limiting structure (1101), and the second insert plate (120) includes a second limiting structure (1201). The first limiting structure (1101) and the second limiting structure (1201) cooperate with each other to limit the position of the first insert plate (110) and the second insert plate (120) relative to each other in the radial and / or axial directions.

6. The seatbelt retraction device (1) according to claim 5, wherein, One of the first limiting structure (1101) and the second limiting structure (1201) is configured as a slot, and the other is configured as a tab, and the tab is positioned in the slot; And / or, Each of the first inner panel (110) and the second inner panel (120) has two bends (1111) at the first shaft end. The two bends (1111) of the first inner panel (110) and the second inner panel (120) are spaced apart in the width direction, and the corresponding bends (1111) of the first inner panel (110) and the second inner panel (120) are aligned in the width direction.

7. The seatbelt retraction device (1) according to claim 1, wherein, The second shaft end of the mandrel (10) includes the second inner shaft end (112) of the insert (11) and the second outer shaft end (102) of the cover (12). The second inner shaft end (112) protrudes axially from the end face of the second outer shaft end (102) to connect with the pretensioner (20).

8. The seatbelt retraction device (1) according to claim 7, wherein, The mandrel (10) includes a narrower middle section located between the first shaft end and the second shaft end, and the middle section is used to wind the webbing of the seat belt.

9. The seatbelt retraction device (1) according to claim 5, wherein, An elongated hole (1103) is provided on the middle section of the first inner panel (110) and / or the second inner panel (120).

10. The seatbelt retraction device (1) according to claim 1, wherein, The insert (11) is made of a stronger material than the cover (12).

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