JPH0687107U - Seat belt retractor - Google Patents

Abstract

(57) [Abstract] [Purpose] To simplify the structure of the seat belt retractor. [Structure] A flange 12 having external teeth on its outer periphery is provided at one end of a winding shaft 10, and a groove 13 provided at the other end is provided at a side wall 24 of a frame 20. It directly engages with the winding shaft locking hole 26.
As a result, displacement of the winding shaft 10 in the axial direction is prevented by a very simple structure, and the end of the winding shaft on the side engaging with the frame is not displaced in the radial direction. It can be easily connected to the biasing means.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a seat belt retractor, and more particularly to a seat belt type in which a toothed flange provided at an end portion of a seat belt is engaged in place to lock the rotation of the retract shaft when the seat belt retractor is displaced. The present invention relates to a belt winding device.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, there is a seat belt retractor used in, for example, an automobile to restrain an occupant to a seat in an emergency. There are various types of seatbelt retractors that are used as an emergency lock. One of them is when the seatbelt takeup shaft is displaced in the axial radial direction. There is also a seat belt retractor in which a toothed flange provided at the end of the shaft engages with a proper position of a frame supporting the shaft to lock the rotation of the take-up shaft. In this seat belt retractor, for example, as shown in FIG. 7, a pair of flanges 72 and 73 having outer teeth formed on the outer circumference are provided at both ends of a shaft portion 71 of a seat belt retractor shaft 70. The frame 80, which rotatably supports the winding shaft 70, is provided with flange insertion holes 85 and 86 with internal teeth, which engage with the external teeth of the flanges 72 and 73, and engage these external and internal teeth. A frame-lock type seat belt retractor 90 is used that locks the rotation of the retractor shaft 70 by making the rotation. Then, in the seat belt retractor 90, when the vehicle body deceleration due to, for example, a sudden braking exceeds a predetermined value, a lock mechanism (not shown) is actuated, and as shown in FIG. The outer teeth provided on the flanges 72 and 73 of the winding shaft 71 and the inner teeth provided on the frame 80 are engaged with each other by displacing in a radial direction with respect to the axis (see FIG. 8). (state shown in b).

[0003]

[Problems to be solved by the device]

 However, in the seat belt retractor 90 described above, since both ends of the retractor shaft 70 are displaced in the radial direction with respect to the axis, as shown in FIG. Does not always act to move normally (move in parallel), and depending on the seat belt withdrawal direction, the winding shaft 70 may be displaced in the axial direction as shown in FIG. 9 (b), for example. Then, there is a drawback that the outer teeth of the flanges 72 and 73 of the winding shaft 70 and the inner teeth of the frame 80 are disengaged from each other. Therefore, for example, as in the seatbelt winding device disclosed in Japanese Patent Laid-Open No. 4-283150, the take-up flange is provided adjacent to the external teeth formed on the outer periphery of the flange so as to prevent the take-up. A special displacement prevention means is required to prevent the shaft 70 from being displaced in the axial direction, which complicates the mechanism. In order to wind up the seat belt and store it in the case, a winding spring (not shown) is connected to one of the shaft end portions 74 and 75 of the winding shaft 70 to rotate in the seat belt winding direction. The winding spring is fixedly attached to the frame 80, while the winding shaft 70 is displaced relative to the frame as described above. Therefore, the mechanism for connecting the winding shaft 70 and the winding spring also becomes complicated.

Therefore, the present invention has been made in view of the above circumstances, and an object thereof is to provide a simple seat belt retractor having a structure capable of solving the above-mentioned drawbacks of the conventional seat belt retractor. To do.

[0005]

[Means for Solving the Problems]

 The above object of the present invention is to rotate a seat belt and support a winding shaft having a flange with teeth formed thereon, the winding shaft so as to be displaceable in the radial direction, and the flange to move in the radial direction. A seatbelt winding device having a frame having teeth that lock the rotation of the winding shaft by engaging with the teeth of the winding shaft when displaced to one end of the winding shaft. In addition to providing the flange, a groove along the axial direction is provided at the opposite end, a flange insertion hole that meshes with the teeth of the flange is provided on one side wall of the frame, and the other side wall is provided. The seat belt is characterized in that a winding shaft engaging hole having an edge portion that engages in the groove is provided in the seat, and the position of the winding shaft is regulated in the axial direction and the radial direction of the shaft. Achieved by the take-up device That.

[0006]

[Action]

 The winding shaft of the seat belt winding device of the present invention has one end directly engaged with the frame so as not to be displaced in the axial direction and the radial direction. It is possible to eliminate the need for special displacement preventing means for preventing the coil from displacing, and to easily connect the winding spring to the end of the winding shaft. The flange provided on the other end of the winding shaft is swingable from the engaging portion on the opposite end as a starting point, and engages with the frame when it is displaced in the radial direction to wind. The rotation of the shaft is locked.

[0007]

【Example】

 An embodiment of a seat belt retractor according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, a seat belt retractor 100 according to the present embodiment has a retractor shaft 10 having an externally toothed flange 12 vertically provided at only one end, and the retractor shaft 10. It has a frame 20 to be attached, an acceleration detecting mechanism (not shown) (a mechanism for detecting acceleration due to a shock such as a collision), and a winding spring mechanism (not shown) for applying an urging force for winding the seat belt. ing. The take-up shaft 10 has a shaft portion 11 to which a take-up reel (not shown) for winding a seat belt is attached, an outer toothed flange 12 vertically provided at one end of the shaft portion 11, and It is composed of a groove 13 provided at an end portion of the shaft portion 11 on the side opposite to the outer toothed flange 12, and reduced diameter terminal shaft portions 14 and 15 provided at both ends of the shaft portion 11. . An acceleration detecting mechanism provided along the first side wall 23 of the frame 20 is connected to the terminal shaft portion 15 on the outer toothed flange 12 side, and the vehicle body is rapidly decelerated by, for example, sudden braking. When this occurs, the outer toothed flange 12 is displaced in the radial direction with respect to the axis of the winding shaft 10. A winding spring mechanism is attached to the terminal shaft portion 14 on the groove 13 side along the second side wall 24 so that the winding shaft 10 is always biased in the winding direction. Is becoming. Further, as shown in FIG. 2, the outer diameter of the shaft portion 11 of the winding shaft 10 is d1, the outer diameter of the bottom portion of the groove 13 is d2, and the width of the groove 13 will be described later. It is made slightly wider than the thickness of the side wall of the frame 20.

The frame 20 has a rectangular bottom plate 21 and a mounting portion 22 provided with a mounting hole extending on one short side of the bottom plate for screwing the frame 20 to, for example, a vehicle body of an automobile. And a pair of first and second side walls 23 and 24 that are vertically provided on the pair of long sides of the bottom plate 21 and face each other. The flange 12 with external teeth of the winding shaft 10 is inserted into the first side wall 23, and the internal teeth engaging with the external teeth are provided on a part of the inner circumference of the flange with internal teeth. An insertion hole 25 is provided. The second side wall 24 is provided with a take-up shaft engaging hole 26 that engages with the groove 13 provided in the take-up shaft 11. As shown in FIG. 3, the winding shaft engaging hole 26 has a through hole having an inner diameter D2 slightly larger than the bottom outer diameter d2 of the groove 13 of the winding shaft 11, and the shaft portion 11 of the winding shaft 11. The through hole having an inner diameter D1 which is slightly larger than the outer diameter d1 of the winding shaft 10 is inserted into the through hole having the inner diameter D1. It is adapted to be able to engage the part.

Next, the operation of the seat belt retractor 100 of the present invention will be described with reference to FIG. As shown in FIG. 4 (a), when the retaining shaft 27 is attached after the groove 13 of the winding shaft 10 is engaged with the winding shaft engaging hole 26, the end of the winding shaft 10 on the groove 13 side is attached. The portion is rotatable with respect to the second side wall 24 of the frame 20, but is axially and non-displaceably supported in the axial direction and the radial direction. The end of the take-up shaft 10 on the side of the flange 12 with external teeth is swingable from the engaging portion with the second side wall 24 as a starting point. Therefore, as shown in FIG. 4 (b), when a sudden deceleration occurs in the vehicle body, a locking means (not shown) connected to the terminal shaft portion 15 of the take-up shaft 10 on the side of the outer toothed flange 12 side is used. The outer toothed flange 12 is displaced to engage the inner tooth of the inner toothed flange insertion hole 25, and the rotation of the winding shaft 10 is locked.

That is, in this embodiment, the groove 13 is provided in the shaft portion 11 of the winding shaft 10, and the groove 13 is directly engaged with the front winding shaft engaging hole 26 of the frame 20. Therefore, the displacement of the winding shaft 10 in the axial direction can be prevented, and the displacement of the engaging portion in the radial direction can be prevented, so that the winding shaft 10 and the winding spring mechanism can be easily connected. can do. Further, the winding shaft engaging hole 26 communicates with a small diameter portion that engages with the groove 13 and a large diameter portion that inserts the shaft portion of the winding shaft 10 and guides the groove 13 to the engaging portion. Because of the structure, the winding shaft 10 can be easily assembled in the winding shaft engaging hole 26.

In the present embodiment, the winding shaft 10 is directly attached to the winding shaft engaging hole 26 provided in the frame 20, but the winding shaft engaging hole 26 is shown in FIG. By attaching such a resin bush 28, the rotation of the winding shaft 10 can be made smoother. In addition, in this embodiment, the shaft portion 11 of the winding shaft 10 is provided with the groove 13 as an engaging portion, but the groove 13 is not limited to the one formed by cutting as shown in FIG. For example, it can be configured as shown in FIG. The configuration shown in FIG. 6 has a circular winding shaft engaging hole 29 (which is slightly smaller than the diameter of the shaft portion 14) in which the reduced diameter terminal shaft portion 14 of the winding shaft 10 is provided in the second side wall 24 of the frame 20. The groove may be formed by inserting the washer 16 and the snap ring 17 together with the groove. In this case, it is not necessary to provide the retaining member 27 as shown in FIG. Further, in the embodiment shown in FIGS. 1 to 4, the retaining member 27 is used as a separate member to prevent the take-up shaft 10 from coming off from the take-up shaft engaging hole 26. The stopper member may be provided integrally with the take-up spring mechanism (integrally formed in the portion facing the second side wall 24).

[0013]

[Effect of device]

 As described above, in the seat belt retractor of the present invention, the engaging portion is provided at one end of the retracting shaft, and the external toothed flange is vertically provided at the other end of the retracting shaft, and one wall surface of the frame is provided. Is formed with an engaging hole that engages with the engaging portion of the take-up shaft to rotate the take-up shaft but does not displace the take-up shaft in the axial direction. Since the internal teeth that engage when the attached flange is displaced are provided, the following excellent effects can be obtained. That is, the winding shaft of the seat belt winding device according to the present invention is configured such that the engaging portion provided at one end thereof is engaged with the engaging hole provided in the frame to displace the winding shaft in the axial direction. This prevents the winding shaft from being disengaged from the frame unlike the conventional seat belt winding device. Furthermore, by directly engaging the winding shaft with the frame, it is possible to eliminate the need for a complicated mechanism for preventing the axial displacement of the winding shaft. Further, since the end of the take-up shaft on the side engaged with the frame is not displaced in the radial direction with respect to the axis of the take-up shaft, the take-up spring mechanism for urging the take-up shaft in the take-up direction and the take-up spring mechanism. It can be easily connected to the take-up shaft.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of essential parts of an embodiment of a seat belt retractor of the present invention.

2 is an enlarged plan view showing a winding shaft shown in FIG. 1. FIG.

FIG. 3 is an enlarged cross-sectional view showing a winding shaft locking hole provided in the frame shown in FIG.

FIG. 4 is a partial cross-sectional plan view for explaining the operation of the seat belt retractor shown in FIG.

FIG. 5 is a perspective view showing a winding shaft locking hole bush provided in the frame of the seat belt winding device according to the present invention.

FIG. 6 is a plan view of a partial cross section for explaining a form of locking the winding shaft end portion to the frame in another embodiment of the seat belt winding device of the present invention.

FIG. 7 is a perspective view showing a frame and a winding shaft of a conventional seat belt winding device.

FIG. 8 is a plan view illustrating an operation of a conventional seat belt retractor.

FIG. 9 is a plan view illustrating a problem of a conventional seat belt retractor.

[Explanation of symbols]

 10 Winding Shaft 11 Shaft Part 12 Flange with External Teeth 13 Groove 14 End Shaft Part 15 End Shaft Part 16 Washer 17 Snap Ring 20 Frame 21 Bottom Plate 22 Attachment Part 23 First Side Wall 24 Second Side Wall 25 Inner Toothed Flange Insertion Hole 26 winding shaft engaging hole 27 retaining member 28 bush 29 shaft insertion hole 100 seat belt winding device of the present invention

Claims (1)

[Scope of utility model registration request] 1. A winding belt which is rotated to wind up a seat belt, and which has a flange having teeth formed thereon, supports the winding shaft so as to be displaceable in a radial direction, and the flange is displaced in a radial direction. In the seat belt retractor including a frame having teeth that lock the rotation of the take-up shaft by engaging with the teeth of the take-up shaft, the flange is provided at one end of the take-up shaft. A groove along the axial direction is provided at the opposite end of the frame, a flange insertion hole that meshes with the teeth of the flange is provided on one side wall of the frame, and a groove is formed on the other side wall in the groove. A seat belt retractor comprising: a retracting shaft engaging hole having an engaging edge portion, wherein the position of the retracting shaft is restricted in an axial direction and a radial direction of the shaft.