JPH043894Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a webbing retractor for retracting webbing for restraining an occupant, which is used in a seat belt device for protecting an occupant during a vehicle emergency.

The webbing take-up device has a take-up shaft that winds one end of the occupant restraint webbing in a layered manner. By applying a webbing winding force to this take-up shaft, the occupant can keep the middle part of the webbing in close contact with the webbing. It is ready to be installed.

Furthermore, in the event of a vehicle emergency, this webbing retractor is designed to stop the webbing unwinding rotation of the retractor shaft and place the occupant in a restrained state with the webbing. Secured.

However, even after the webbing unwinding rotation of the take-up shaft stops in the event of a vehicle emergency, the webbing that has been wound up in layers on the take-up shaft comes into close contact with each other before the webbing is worn by the passenger. A so-called tightening phenomenon in which the webbing is pulled out in the direction of the webbing may occur, increasing the length of the webbing worn by the occupant.

For this reason, a webbing lock device has conventionally been proposed that clamps and locks the intermediate portion of the webbing between the take-up shaft and the occupant restraint portion to stop the longitudinal movement of the webbing in the event of a vehicle emergency. However, this webbing lock device has a complicated structure and is complicated in design in order to reliably prevent longitudinal movement without damaging the intermediate portion of the webbing.

In consideration of the above facts, the present invention aims to provide a webbing retractor that has a simple structure and can reliably reduce winding tightness and improve occupant restraint performance.

The webbing take-up device according to the present invention has a roller that is supported parallel to the take-up shaft, around which the middle part of the webbing unwound from the take-up shaft is wound, and that is capable of contacting the webbing wound around the take-up shaft. However, in the normal state of the vehicle, the webbing is held by a spring at a position separated from the webbing wound around the take-up shaft. Therefore, this roller does not prevent the webbing from being unwound from the take-up shaft in the normal state of the vehicle, and the webbing can be easily pulled out.

In addition, the outer circumference of this roller is engraved with unevenness and a soft resin is provided on the outer circumferential surface, and in the event of a vehicle emergency, this roller approaches the winding shaft due to the tension of the webbing, and winds the winding in layers on the winding shaft. The webbing that has been taken up is pushed in the direction of the take-up shaft, and the webbing taken up on the take-up shaft is taken up by using the rotational force of the roller generated by the tensile force that acts on the webbing in a vehicle emergency situation. By rotating in the direction, the winding of the layered winding portion is prevented from tightening.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the webbing retractor 10 according to this embodiment has a base frame 12 fixed to a vehicle body 16 with mounting bolts 14.

A pair of leg plates 18 and 20 extend parallel to each other from both sides of the base frame 12.
The winding shaft 22 is pivotally supported near both ends thereof. As shown in FIG. 1, this winding shaft 22 is provided with a slit 24 that passes through it in the radial direction. The center portion of the slit 24 in the penetrating direction is a neck portion 26, and a locking pin 2 disposed on one side of the neck portion 26
8 is a ring portion 3 formed at the end of the occupant restraint webbing 30 which is inserted from the opposite side of the neck portion 26.
0A is fitted and attached to the winding shaft 22, and cannot be pulled out from the slit 24.

The winding shaft 22 is provided with a mainspring spring winding device 32 between the end protruding from the leg portion 20 and the leg plate 20, and is biased in the webbing winding direction (direction of arrow A) to restrain the occupant. The ends of the webbing 30 are wound in layers.

A ratchet foil 34 is provided in the middle of the winding shaft 22.
is fixed so that it can rotate together with the winding shaft 22, and corresponds to the pawl 36 that is pivotally supported on the leg plates 18 and 20. This pole 36 is Rotsuka arm 3
8 onto the pendulum 40. This pendulum 40 is suspended from a bracket 42 fixed to the leg plate 18, and when the pendulum 40 is tilted in the event of a vehicle emergency, it pushes up the pawl 36 via the rocker arm 38, engages with the ratchet wheel 34, and locks the take-up shaft 2.
The webbing unwinding rotation of No. 2 is stopped.

A pair of elongated holes 44 are bored in the leg plates 18 and 20 below the winding shaft 22, and the vicinity of both ends of the moving shaft 46 are pivotally supported. The longitudinal direction of this elongated hole 44 is the direction in which it approaches and leaves the winding shaft 22.

A roller 48 is pivotally supported on the moving shaft 46 .
As shown in FIG. 2, this roller 48 has a longitudinal dimension slightly smaller than the distance between the ratchet wheel 34 and the leg plate 20, and has a plurality of irregularities 4 on its outer periphery.
8A is engraved, and the intermediate portion of the webbing 30 extending from the winding shaft 22 to an unillustrated occupant restraint portion is wound around about half of the circumference. Here, the direction in which the webbing 30 is wound around the roller 48 is the same direction as the take-up shaft 22, so that when the webbing 30 is drawn out and taken up, the roller 48 rotates in the same direction as the take-up shaft 22. I'm starting to do this.

One end of a tension coil spring 50 is secured to each end of the moving shaft 46 protruding from the leg plates 18, 20, and the other end of the tension coil spring 50 is connected to a cutout provided in a part of the leg plates 18, 20. Bending part 5
It is locked to 2. This tension coil spring 50
In this case, the moving shaft 46 is arranged at the end of the elongated hole 44 farthest from the winding shaft 22. However, this tension coil spring 50 bends when the tension of the webbing 30 increases, allowing the moving shaft 46 to move along the elongated hole 44, thereby causing the roller 48 to approach the winding shaft 22 and move the third As shown in the figure, it is possible to contact the webbing wound around the winding shaft.

Next, the operation of this embodiment will be explained. In the normal state of the vehicle, the pawl 36 is separated from the ratchet wheel 34, and the roller 48 is separated from the layered webbing wound onto the winding shaft 22, so the occupant can arbitrarily unwind the webbing 30 from the winding shaft 22. , can be rolled up. Therefore, the occupant can freely wear the webbing 30 and assume any driving position.

When the vehicle is in an emergency situation such as a collision, the pendulum 40 tilts and moves the pawl 36 towards the ratchet wheel 3.
4, the webbing unwinding rotation of the winding shaft 22 is stopped. At the same time, webbing 3
Since the occupant wearing the intermediate part of 0 is violently thrown in the direction of the collision, a large tension is generated in the webbing 30.

Due to this tension, the roller 48 around which the intermediate portion of the webbing is wound bends the tension coil spring 50 and moves to approach the take-up shaft 22. As a result, as shown in FIG.
2 and presses the layered webbing toward the axis of the winding shaft 22.

As a result, the tension of the webbing wound in layers on the take-up shaft 22 is reduced, and the webbing 30 is not pulled out from the take-up shaft 22 whose unwinding rotation has been stopped due to the winding tightening, and the occupant is unable to pull out the webbing. is reliably restrained by the stopped webbing 30, improving safety. In particular, since the roller 48 rotates in the winding direction of the winding shaft 22 as shown by arrow B in FIG.
This generates a frictional force that rotates the webbing in the winding direction, thereby stopping the layered webbing from being pulled out and improving the performance of restraining the occupant.

Here, a plurality of irregularities 48A are formed on the outer periphery of the roller 48.
By providing this, the frictional resistance between the webbing 30 and the webbing 30 is increased, and the effect of preventing winding from tightening is further improved. The outer periphery of the roller 48 can be provided with even finer irregularities than the first and third irregularities 48A, such as a gear shape, a knurling shape, a satin finish, etc. Also roller 48
The frictional resistance between the roller and the webbing can also be increased by coating the surface of the roller with a soft synthetic resin.

As explained above, the webbing retractor according to the present invention is rotatably supported in parallel with the take-up shaft, and the intermediate portion of the webbing unwound from the take-up shaft is wound, and the webbing taken up on the take-up shaft is In a normal state of the vehicle, the contactable roller is held by a spring at a position spaced apart from the webbing wound around the take-up shaft. Therefore, this roller does not prevent the unwinding of the webbing from the take-up shaft in the normal state of the vehicle, and has an excellent effect of allowing the webbing to be easily pulled out.

In addition, in the event of a vehicle emergency, a roller with unevenness engraved on the outer periphery and a soft resin on the outer periphery surface approaches the winding shaft under webbing tension, and winds up the webbing wound in layers onto the winding shaft. By pressing in the axial direction and rotating the webbing wound around the winding shaft in the winding direction by utilizing the rotational force of the roller generated by the tensile force acting on the webbing in a vehicle emergency state, This is designed to prevent the layered winding portion from becoming too tight. Therefore, although it has a simple structure, it has an excellent effect of reliably reducing winding tightness and improving occupant restraint performance.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the webbing retractor according to the present invention, FIG. 2 is a left side view of FIG. 1 (however, the pawl 36 and related parts are omitted), and FIG. is an operational diagram of FIG. 1. 10... Webbing winding device, 22... Winding shaft, 30... Webbing, 48... Roller, 48
A...Unevenness, 50...Tension coil spring.

Claims (1)

[Scope of utility model registration request] A take-up shaft around which one end of the occupant restraint webbing is wound up in a layered manner; and a take-up shaft that is supported parallel to the take-up shaft and around which an intermediate portion of the webbing that is unwound from the take-up shaft is wound. a roller capable of contacting the webbing wound around the winding shaft; and a roller that holds the roller in a position separated from the webbing winded around the winding shaft in a normal state of the vehicle, and moves the roller toward the winding shaft using webbing tension in a vehicle emergency. A webbing take-up device having a spring that is brought close to each other and capable of pressing the layered webbing in the direction of the winding axis, wherein the roller has irregularities carved on the outer periphery and a soft resin is provided on the outer periphery surface. A webbing take-up device characterized by: