Seat belt retractor

Abstract

A seat belt retractor is provided. The seat belt retractor includes a spool and a pretensioner. The spool winds a seat belt on a lateral surface thereof by rotating in a winding direction. The pretensioner is provided on an axial side of the spool and drives the spool to rotate in the winding direction under a predetermined condition. The pretensioner includes a rotating member and a moving lever. The rotating member is connected to the spool so as to rotate together, and includes a main body portion and a tooth portion extending radially outward from the main body portion. The moving lever is flexible and is driven to engage with the tooth portion of the rotating member, thereby bringing the spool to rotate in the winding direction. The rotating member includes a plurality of sheet members stacked in an axial direction. Each of the sheet members includes a sub-main body portion and a sub-tooth portion extending radially outward from the sub-main body portion. The plurality of sub-main body portions collectively define the main body portion, and the plurality of sub-tooth portions collectively define one tooth portion.

Description

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 them from secondary impacts with the steering wheel and dashboard, or from being ejected from the vehicle and suffering injury or death. Seat belt retraction devices with pre-tensioning functions already exist. In such devices, during an emergency, the pre-tensioning mechanism rotates the mandrel in the retraction direction, thereby retracting the seat belt onto the mandrel. Specifically, a gas generator drives a moving member to engage with multiple teeth spaced circumferentially along the rotation direction of the mandrel, thereby driving the mandrel to rotate in the retraction direction to retract the seat belt.

[0003] The aim is to provide a seatbelt retraction device with minimal energy loss during pre-tensioning. Summary of the Invention

[0004] The purpose of this invention is to provide a seat belt retraction device with a pre-tensioning function, and with less energy loss during pre-tensioning, especially less energy loss of the teeth of the moving and rotating parts during engagement.

[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 pretensioner is disposed on one axial side of the mandrel and, under predetermined conditions, drives the mandrel to rotate in the winding direction;

[0008] in,

[0009] The pretensioner includes:

[0010] A rotating component, which is connected to the mandrel in a manner that allows it to rotate together, and includes a main body and teeth extending radially outward from the main body; and

[0011] The movable rod is flexible and is driven to engage with the teeth of the rotating member, thereby causing the mandrel to rotate in the winding direction.

[0012] The rotating component includes a plurality of sheet members stacked axially, wherein each sheet member includes a sub-body portion and a sub-tooth portion extending radially outward from the sub-body portion, and the plurality of sub-body portions collectively define the body portion, and the plurality of sub-tooth portions collectively define a tooth portion.

[0013] According to an embodiment of the present invention, the first sub-side surfaces of two adjacent sub-teeth in a plurality of sub-teeth are offset by a predetermined angle in the circumferential direction, and the plurality of first sub-side surfaces define a first side surface of a tooth, wherein the first side surface is located on the side of each tooth opposite to the winding direction.

[0014] According to an embodiment of the present invention, the first side has a shape profile adapted to the end of the moving rod that will engage with the rotating member.

[0015] According to an embodiment of the present invention, the first side surface is raised along the winding direction.

[0016] According to an embodiment of the present invention, a first fixing structure is provided on the sub-body portion, and a second fixing structure is provided at one end of the mandrel. The first fixing structure and the second fixing structure cooperate to fix the rotating member and the mandrel.

[0017] According to an embodiment of the present invention, one of the first fixing structure and the second fixing structure is configured as a groove, and the other is configured as a protrusion that mates with the groove.

[0018] According to an embodiment of the present invention, each of the sub-teeth is configured to have a first sub-side face and a second sub-side face that are radially symmetrical.

[0019] According to an embodiment of the present invention, the sub-tooth portion has a tooth root connected to the sub-body portion and a tooth tip radially opposite to the tooth root, and the sub-tooth portion gradually narrows in circumferential dimension from the tooth root to the tooth tip.

[0020] According to an embodiment of the present invention, the number of the sheet components is set in the range of 5-40;

[0021] And / or,

[0022] Nine to 13 sub-teeth are provided along the circumference of the sheet.

[0023] And / or,

[0024] The predetermined angle at which two adjacent sub-teeth are offset in the circumferential direction is in the range of 0-9 degrees.

[0025] According to an embodiment of the present invention, the plurality of said sheet elements are configured to be identical to each other.

[0026] And / or,

[0027] The tooth tip radius (R-angle) of the sub-tooth section has a radius of 0.2-0.5 mm. Attached Figure Description

[0028] 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:

[0029] Figure 1 An exploded view schematically illustrating a seatbelt retraction device according to an embodiment of the present invention is shown.

[0030] Figure 2 The diagram schematically illustrates some components of a seatbelt retractor according to an embodiment of the present invention.

[0031] Figure 3 Another component of the seatbelt retractor is schematically shown in an embodiment of the invention.

[0032] Figure 4 An exploded view schematically illustrating a component of a seatbelt retraction device according to an embodiment of the present invention. Detailed Implementation

[0033] 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.

[0034] 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.

[0035] Figure 1 An exploded view schematically illustrating a seatbelt retraction device according to an embodiment of the present invention is shown. Reference is made below. Figure 1 A seatbelt retraction device according to an embodiment of the present invention is described.

[0036] like Figure 1 As shown, 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.

[0037] The mandrel 10 is generally cylindrical and is positioned inside the frame 50. Specifically, as... Figure 1 As shown, the frame 50 includes two side plates arranged opposite each other in the left-right direction. The two axial ends of the spindle 10 are respectively positioned on these two side plates of the frame 50 and are capable of rotating around their own central axis. In addition, one end of the seat belt webbing (not shown) along the length direction is fixed on the circumferential side of the spindle 10. When the spindle 10 rotates in the winding direction, the seat belt webbing will be wound onto the spindle 10. Conversely, when the spindle 10 rotates in the unwinding direction, the seat belt webbing will leave the spindle 10. In this way, the occupant can adjust the wearing length of the seat belt.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] Figure 2 The diagram schematically illustrates some components of a seatbelt retractor according to an embodiment of the present invention. Figure 3 Another component of the seatbelt retractor is schematically shown in an embodiment of the invention. Figure 4 An exploded view schematically illustrating a component of a seatbelt retraction device according to an embodiment of the present invention is shown below. (Refer to...) Figures 2 to 4 A seatbelt retraction device according to an embodiment of the present invention is described.

[0042] Figure 2 and Figure 3 Schematic diagrams are shown respectively of a seatbelt retractor according to an embodiment of the present invention, showing some components in an assembled state or an operational state. Specifically, Figure 2 The diagram schematically shows the pawl 34 of the locking assembly 30 mounted on the left end face of the spindle 10, and the rotating member 100 of the pretensioner 20 mounted on the right end face of the spindle 10. 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. Figure 3 The diagram schematically illustrates the engagement of the moving rod 23 of the pretensioner 20 with the rotating member 100. The moving rod 23 moves upward and drives the rotating member 100, thereby driving the mandrel 10 to rotate in the winding direction C to wind the seatbelt webbing onto the mandrel 10. Figure 2 As shown, the mandrel 10 has a generally cylindrical circumferential side surface for winding up the seat belt webbing (not shown). When the mandrel 10 rotates in the winding direction C, the seat belt webbing is wound onto the circumferential side surface. Also, when the seat belt winding device 1 is in... Figure 3 In the indicated orientation, when a predetermined condition is met (e.g., acceleration due to emergency braking exceeds a predetermined value), the moving rod 23 moves upward to drive the mandrel 10 to rotate in the winding direction C. Figure 2 and Figure 3As shown, the rotating member 100 includes a main body 102 and teeth 101 extending radially outward from the main body 102. When the moving rod 23 engages with the teeth 101, the teeth 101 embed into the flexible moving rod 23, thereby causing plastic deformation of the moving rod 23. This plastic deformation of the moving rod 23 due to engagement with the teeth 101 results in energy loss during the pre-tightening process. To reduce this energy loss, in the seatbelt retraction device of the present invention, the rotating member 100 is configured to have a plurality of sheet members 110, which are stacked axially on the mandrel 10. This will be described in more detail below.

[0043] Combination Figure 4 As shown, the sheet member 110 includes a sub-body portion 1102 and sub-tooth portions 1101 extending radially outward from the sub-body portion 1102. When these sheet members 110 are stacked axially, the plurality of sub-body portions 1102 collectively define a body portion 102, and the plurality of sub-tooth portions 1101 collectively define a tooth portion 101. In the embodiment shown in the figure, seven sheet members 110 are provided, and each sheet member 110 is configured to be identical to each other, and each sheet member 110 has eleven sub-tooth portions 1101 arranged circumferentially. The sub-body portions 1102 of the sheet members 110 are used to define the body portion 102, that is, the seven sub-body portions 1102 are used to collectively define the body portion 102. In this example, the rotating member 100 includes a body portion 102 and eleven teeth portions 101, therefore, these seven sub-body portions 1102 define the unique body portion 102 of the rotating member 100. Furthermore, every eleven sub-teeth 1101 can be considered as a group, and this group of sub-teeth 1101 collectively defines a tooth 101. That is, the eleven sub-teeth 1101 in the first group collectively define the first tooth 101, the eleven sub-teeth 1101 in the second group collectively define the second tooth 101, and so on, with the eleven sub-teeth 1101 in the eleventh group collectively defining the eleventh tooth 101. Of course, the embodiment shown in the figure is merely an example. In reality, the number of sheet members and the sub-teeth on them can be set differently as needed. In one example, the number of sheet members can be set in the range of 5-40; in another example, the sheet member can have 9-13 sub-teeth arranged circumferentially. Moreover, multiple sheet members can have different designs, for example, different numbers of teeth and different tooth profiles.

[0044] It should be noted that in the seatbelt retraction device of the present invention, the rotating component is configured as a plurality of stacked thin sheets, which is beneficial to reducing energy loss during the pre-tensioning process. This is because the rotating component with this structural form can have sharp tooth tips, which can be obtained through a precision stamping process. As an example, the tooth tip R angle of the sub-tooth portion 1101 of the thin sheet 110 can have a fillet radius of 0.2-0.5 mm. It should be noted that the sharper the tooth tip of the rotating component, the less energy loss during the pre-tensioning process. Therefore, the seatbelt retraction device of the present invention has less energy loss during pre-tensioning.

[0045] As an embodiment of the present invention, such as Figure 4 As shown, the sub-tooth portion 1101 includes a tooth root and a tooth tip. The tooth root is connected to the sub-body portion 1102 and is radially opposite to the tooth tip. The sub-tooth portion 1101 gradually narrows from the tooth root to the tooth tip along its circumferential dimension. Correspondingly, the tooth portion 101 of the rotating member 100 also gradually narrows from the tooth root to the tooth tip along its circumferential dimension, thereby giving the tooth portion 101 of the rotating member 100 a sharp tooth tip.

[0046] The arrangement of the sheet components in the rotating parts is described in detail below.

[0047] As one embodiment of the present invention, such as Figure 2 As shown, when mounted to one end of the spindle 10, the sub-teeth 1101 of the plurality of sheet members 110 are aligned in the circumferential direction. In this case, the teeth 101 of the rotating member 100 may have two circumferential side surfaces that are substantially flat.

[0048] As another embodiment of the present invention, such as Figure 3 As shown, when mounted to one end of the mandrel 10, the tooth tips of the plurality of sheet members 110 are misaligned in the circumferential direction. Specifically, each sub-tooth portion 1101 has a first sub-side surface 1101A and a second sub-side surface 1101B, which are opposite to each other in the circumferential direction of the sheet member 110. As an embodiment of the present invention, the first and second sub-side surfaces of each sub-tooth portion 1101 can be configured to be radially symmetrical to reduce machining difficulty and cost.

[0049] When installed on one end of the mandrel 10, the first sub-side face 1101A of two adjacent sub-teeth 1101 are offset by a predetermined angle in the circumferential direction, and the plurality of first sub-side face 1101A similarly define the first side face 100A of a tooth 101. Figure 3As shown, in the direction from the rear to the front, the first sheet member 110 and its adjacent second sheet member 110 are offset by a predetermined angle in the circumferential direction, the second sheet member 110 and its adjacent third sheet member 110 are offset by a predetermined angle in the circumferential direction, and so on, the sixth sheet member 110 and its adjacent seventh sheet member 110 are offset by a predetermined angle in the circumferential direction. As an example, the predetermined angle offset between two adjacent sub-teeth in the circumferential direction can be set in the range of 0-9 degrees.

[0050] It should be noted that, as Figure 3 As shown, with the fourth sheet 110 as the line of symmetry, the sheet members 110 on the front and rear sides are symmetrical to each other to match the shape of the end 231 of the moving rod 23. Specifically, the first side surface 100A of the rotating member 100 defined by the plurality of sheet members 110 is positioned on the side opposite to the winding direction C in each tooth 101. When engaged with the moving rod 23, the end 231 of the moving rod 23 will contact this first side surface 100A of the tooth 101. For this purpose, the first side surface 100A has a shape profile adapted to the end 231 of the moving rod 23 that will engage with the rotating member 100. For example, this end 231 of the moving rod 23 has a convex end face, and correspondingly, the first side surface 100A bulges along the winding direction to adapt to the shape of the end 231 of the moving rod 23. This helps to improve the smoothness of the initial engagement between the moving rod 23 and the rotating member 100. Of course, this is just an example; the teeth of the rotating part can also have other designs depending on the different designs of the ends of the moving rod.

[0051] It should be noted that the design of the sub-teeth of the multiple thin pieces of the rotating component being offset in the circumferential direction can be understood as giving the rotating component a greater number of teeth arranged in the circumferential direction. Therefore, when the moving rod engages with the rotating component, the engagement process between the moving rod and the rotating component with these teeth will be more stable, thereby improving the operational stability during pre-tightening.

[0052] As an embodiment of the present invention, in order to fix the mandrel 10 and the rotating member 100, such as Figure 3As shown, a first fixing structure 1103 is provided on the sub-body 1101, and a second fixing structure is provided at one end of the mandrel 10. The first fixing structure 1103 cooperates with the second fixing structure. In one example, the first fixing structure 1103 is configured as a groove, and the second fixing structure is configured as a protrusion that cooperates with the groove. After the protrusion of the mandrel 10 is inserted into the respective grooves of the plurality of sheet members 110, a stop member (e.g., a bushing) is fixed at the end of the protrusion to fix the plurality of sheet members 110 to the end of the mandrel 10. Of course, this is just an example. The mandrel and rotating member of the present invention are not limited to the above-described fixing method and may have other forms of fixing structures. For example, the second fixing structure may be configured as a groove, and the first fixing structure may be configured as a protrusion that cooperates with the groove.

[0053] 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 (C); A pretensioner (20) is disposed on one axial side of the mandrel (10) and, under predetermined conditions, drives the mandrel (10) to rotate in the winding direction (C); Its features are, The pretensioner (20) includes: A rotating member (100) connected to the mandrel (10) in a rotatable manner, and comprising a main body (102) and teeth (101) extending radially outward from the main body (102); and The movable rod (23), which is flexible, is driven to engage with the teeth (101) of the rotating member (100), thereby driving the spindle (10) to rotate in the winding direction (C); The rotating member (100) includes a plurality of sheet members (110) stacked in the axial direction, wherein each sheet member (110) includes a sub-body portion (1102) and a sub-tooth portion (1101) extending radially outward from the sub-body portion (1102), and the plurality of sub-body portions (1102) together define the body portion (102), and the plurality of sub-tooth portions (1101) together define one tooth portion (101).

2. The seat belt retraction device (1) according to claim 1, wherein, The first sub-side surface (1101A) of two adjacent sub-teeth (1101) are offset by a predetermined angle in the circumferential direction, and the plurality of first sub-side surfaces (1101A) define a first side surface (101A) of a tooth (101), wherein the first side surface (101A) is located on the side of each tooth (101) opposite to the winding direction (C).

3. The seatbelt retraction device (1) according to claim 2, wherein, The first side (101A) has a shape profile that is adapted to the end (231) of the moving rod (23) that will engage with the rotating member (100).

4. The seat belt retraction device (1) according to claim 3, wherein, The first side (101A) is raised along the winding direction (C).

5. The seatbelt retraction device (1) according to claim 1, wherein, The sub-body part (1102) is provided with a first fixing structure (1103), and a second fixing structure is provided at one end of the spindle (10). The first fixing structure (1103) cooperates with the second fixing structure to fix the rotating part (100) and the spindle (10).

6. The seatbelt retraction device (1) according to claim 5, wherein, One of the first fixing structure (1103) and the second fixing structure is configured as a groove, and the other is configured as a protrusion that mates with the groove.

7. The seatbelt retraction device (1) according to claim 2, wherein, Each of the sub-teeth (1101) is configured to have a first sub-side face (1101A) and a second sub-side face (1101B) that are radially symmetrical.

8. The seatbelt retraction device (1) according to claim 7, wherein, The sub-tooth portion (1101) has a tooth root connected to the sub-body portion (1102) and a tooth tip that is radially opposite to the tooth root, and the sub-tooth portion (1101) gradually narrows from the tooth root to the tooth tip along the circumferential dimension.

9. The seatbelt retraction device (1) according to claim 2, wherein, The number of the sheet pieces (110) is set in the range of 5-40; And / or, Nine to 13 sub-teeth (1101) are provided along the circumference of the sheet (110). And / or, The two adjacent sub-teeth (1101) are offset by a predetermined angle in the circumferential direction within the range of 0-9 degrees.

10. The seatbelt retraction device (1) according to claim 1, wherein, The plurality of said sheet pieces (110) are configured to be identical to each other. And / or, The tooth tip radius (R) of the sub-tooth portion (1101) has a radius of 0.2-0.5 mm.

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