JPH0245093Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a webbing winding device for winding up webbing for restraining an occupant, which is used in a seat belt device for protecting an occupant in a vehicle emergency.

[Background technology]

In the seat belt device, one end of the webbing for restraining an occupant is wound up and stored in a webbing take-up device.

This webbing retractor is provided with a lock mechanism to ensure that the occupant is restrained by the webbing in the event of a vehicle emergency. As this locking mechanism, an automatic locking mechanism that prevents the webbing from being pulled out after the occupant has put on the webbing is widely used.

This automatic locking mechanism detects when the occupant attaches and releases the webbing by the rotation of the webbing take-up shaft, and controls the pawl that engages with the ratchet foil fixed to the webbing take-up shaft using a control board. It is designed to prevent the webbing from being pulled out later.

However, in conventional webbing take-up devices, the means for detecting the rotation of the take-up shaft and controlling the movement of the poles is complicated and includes a large number of parts, which may result in increased costs. In addition, when the take-up shaft winds up webbing, an arm body is attached to the take-up shaft to prevent the pole from hitting the bottom of the ratchet foil, which prevents the pole from coming into contact with the ratchet foil, causing abnormal noise. There is a webbing retractor that prevents
3635420). In this webbing take-up device, an arm body having two arms is attached to an end of a take-up shaft. When winding the webbing, one arm engages with the pole to prevent the pole from coming into contact with the ratchet wheel. For this reason, the arm body becomes large and the weight of the arm body is applied to the winding shaft, resulting in a disadvantage that the resistance force of the mainspring spring for winding the winding shaft becomes large.

[Purpose of invention]

The present invention was devised in view of the above circumstances, and its purpose is to provide a webbing take-up device that has a simple structure, completely prevents the occurrence of abnormal noise, and does not impart a large resistance force to the mainspring spring that winds the take-up shaft. Our goal is to provide the following.

[Structure of the idea]

In the webbing take-up device according to the present invention, the rotation of the webbing take-up shaft is transmitted to the friction member pressed against the take-up shaft, and the friction member is rotatable by a predetermined angle by a regulating means such as a pin, and the webbing is attached by the occupant. Inside, the friction member receives a rotational force in the webbing unwinding direction and maintains the pole in a disengaged state with the ratchet foil, and after the webbing is attached, the pole engages with the ratchet foil by receiving a rotational force in the webbing winding direction by the mainspring spring. At the same time, when an arm is connected to the pole and the webbing is retracted, the friction member maintains the pole and the ratchet wheel in a disengaged state via the arm, thereby preventing abnormal noise. are doing. Moreover, in the present invention, since the arm is connected to the pole, the weight of the winding shaft can be suppressed and the resistance force of the mainspring spring can be reduced.

[Embodiment of the invention] Figs. 1 and 2 show a webbing retractor 10 to which the invention is applied.

In this webbing retractor 10, a base 12 is fixed to a vehicle body 16 with bolts 14. A pair of leg plates 18 and 20 protrude from both sides of the base 12 in parallel with each other, and pivotally support the vicinity of both ends of the webbing take-up shaft 22.

One end of an occupant restraining webbing 24 is locked to the intermediate portion of the winding shaft 22. Further, a mainspring spring 26 is provided between the end of the winding shaft 22 protruding from the leg plate 20 and the leg plate 20, and this biases and rotates the winding shaft 22 in the winding direction of the webbing 24. ing.

Ratchet wheels 28 are fixed to the winding shaft 22 on both sides of the webbing 24 so as to rotate together with the winding shaft 22. This ratchet wheel 28 has a pole 30 which is pivotally supported on the leg plates 18 and 20.
is compatible. This pole 30 has leg plates 18, 2
It is accommodated in a shaft support hole 32 formed at 0,
When engaged with the ratchet wheel 28, the webbing drawer rotation of the take-up shaft 22 is stopped.

Further, a winding diameter sensing arm 34 is fixed to the intermediate portion of the pole 30, and the curved tip of the winding diameter sensing arm 34 is in contact with the outer surface of the webbing on the winding shaft 22. This winding diameter sensing arm 34 is connected to the webbing 2
4 is wound onto the winding shaft 22 by the mainspring spring winding device 26, the outer diameter of the webbing 24 increases and the pole 30
is maintained in a disengaged position with the ratchet wheel 28 (see FIG. 5). However, the crew member
When the pawl 4 is pulled out and installed, the outer diameter of the pawl 30 becomes smaller so that the pawl 30 can engage with the ratchet wheel 28.

End portion 22A of the winding shaft 22 protruding from the leg plate 18
As shown in FIG. 2, a spring member 36 is fitted therein. The spring member 36 has a forked shape and includes two legs 38 and 40, the tips of which are curved outward from each other and pressed against the end 22A of the winding shaft 22. The tip of the spring member 36, that is, the leg 3
The connecting portions 8 and 40 are in contact with the pole 30.

Since the spring member 36 has a spring property in the direction in which the legs 38 and 40 approach each other, when the winding shaft 22 rotates, the spring member 36 rotates following the rotation of the winding shaft 22 due to frictional force. However, spring member 3
Since the pins 42 and 44 are arranged on both sides of the winding shaft 6, the rotation of the spring member 36 is restricted between the pins 42 and 44, and when the winding shaft 22 further rotates, the spring member 3
6 is adapted to slip on the winding shaft 22. Therefore, the two pins 42 and 44 constitute a turning angle regulating means for the spring member 36.
In this embodiment, the pins 42 and 44 are implanted in the cover 46, but they may also be provided on the outer surface of the leg plate 18 (see FIG. 1).

On the other hand, since a tension coil spring 48 is connected to the pawl 30 as shown in FIG. ing. The pole 30 in this figure is prevented from pivoting by a spring member 36.

Further, when the take-up shaft 22 rotates in the webbing pulling direction, the spring member 36 rotates until it comes into contact with the pin 42 as shown in FIG. 2. In this state, the spring member 36
In the first position, the pawl 30 is spaced apart from the ratchet foil 28. If the spring member 36 rotates even slightly in the winding direction from this state, the pawl 30 will be in the second position shown in FIG. 3 and can be engaged with the ratchet wheel 28.

Furthermore, in this embodiment, an arm 50 is connected to the end of the pole 30 protruding from the leg plate 18, and the tip of the arm 50 extends in substantially the same direction as the tip of the pole. The arm 50 is made of a flexible material such as resin, and the intermediate portion thereof is bent or curved outward in the radial direction of the ratchet foil 28 to form a recess 50A. Therefore, when the spring member 36 rotates in the winding direction when winding up the webbing 24, the spring member 36 contacts the pin 44 and at the same time the arm 50
The pawl 30 is rotated clockwise together with the pawl 30 to separate the pawl 30 from the ratchet wheel 28 (see FIG. 4).

This structure completely prevents abnormal noises occurring between the pole 30 and the ratchet wheel 28 while the webbing 24 is being wound up. When the pole 30 is locked, the spring member 36 corresponds to the recess 50A of the arm 50, as seen in FIG. Note that the arm 50 may be integrally molded with the pole 30 in advance.

The webbing retractor 10 of this embodiment configured as described above performs an automatic locking operation in the following order.

FIG. 5 shows the webbing 24 in a fully wound state when the occupant has released the webbing 24 from being attached. In order to attach the webbing 24, the occupant pulls out the end (not shown) of the webbing 24 and engages the tongue plate attached to this end with the buckle, thereby attaching the webbing 24.
4 intermediate parts can be attached.

When the webbing 24 is fully wound, the pole 30 is pressed down by the winding diameter sensing arm 34, and when the occupant pulls out the webbing 24, the spring member 36 along with the winding shaft 22 moves clockwise until it hits the pin 42. rotate. As the webbing winding diameter decreases, the winding diameter sensing arm 34 and the pawl 30 also try to pivot counterclockwise, but as shown in FIG. 2, the spring member 36 now maintains the pawl 30 in a disengaged state. . Therefore, pulling out the webbing 24 is not hindered.

Next, when the occupant puts on the webbing 24, the occupant's posture changes and abdominal changes such as breathing occur before or immediately after assuming the driving position, so the webbing 24 is wound around the winding shaft 22 by a small amount. It will be done. As a result, the spring member 36 also pivots in the winding direction (counterclockwise in the top of FIG. 2) to the state shown in FIG. 3, and the action of the spring member 36 to prevent the pawl 30 from turning is released. Therefore, the pawl 30 engages with the ratchet wheel 28 by the biasing force of the tension coil spring 48, as shown in FIG.
Rotation in the webbing unwinding direction of No. 2 is prevented.

To release the webbing unwinding stop of the winding device, remove the tongue plate from the buckle and transfer the entire amount of webbing 24 to the mainspring winding device 26.
(FIG. 1), it is sufficient to wind it onto the winding shaft 22.
When the winding shaft 22 rotates in the winding direction, the spring member 36 rotates accordingly until it comes into contact with the pin 44, as shown in FIG. Therefore, while the webbing 24 is being wound up, no collision noise between the pole 30 and the ratchet wheel 28, that is, no abnormal noise is generated. Moreover, in the present invention, since the arm 50 that prevents contact between the ratchet wheel 24 and the pole 30 during webbing winding is fixed to the pole 30, the arm 50 is not formed on the spring member 36 etc. attached to the winding shaft 22. You can. Therefore, since the arm 50 can suppress an increase in weight on the winding shaft 22 side, the resistance force of the mainspring spring 26 for winding the winding shaft 22 can be reduced. As a result, when the webbing is taken up, the webbing 24 is quickly moved to the take-up shaft by the mainspring spring 26.
It is wound up in 2. Furthermore, as the winding diameter of the webbing 24 increases, the winding diameter sensing arm 34 rotates clockwise, so that the pawl 30 is further separated from the ratchet wheel 28, and as shown in FIG.
It also moves away slightly from the spring member 36 and returns to its initial state.

Alternatively, the pawl 30 may be provided above the ratchet wheel 28 and engaged with the ratchet wheel 28 by its own weight. Since this webbing retractor 10 performs an automatic locking function, it is possible to securely restrain not only the occupant but also luggage on the seat.

[Effect of idea]

As mentioned above, the webbing retractor of the present invention has a simple structure and has the advantages of completely preventing abnormal noises that occur when retracting the webbing, and not imparting large resistance to the mainspring spring that winds up the retracting shaft. It has a great effect.

[Brief explanation of the drawing]

Fig. 1 is a partial vertical sectional view of the webbing retractor according to the present invention, Fig. 2 is a left side view with part of the leg plate and cover removed, Fig. 3 is a left side view in the locked state, FIG. 4 is a left side view showing an initial state of webbing winding, and FIG. 5 is a left side view showing a fully wound state of the webbing. DESCRIPTION OF SYMBOLS 10... Webbing winding device, 22... Winding shaft, 24... Webbing, 28... Ratchet foil, 30... Pole, 34... Winding diameter sensing arm, 36... Spring member, 42, 44... Pin , 5
0...Arm.

Claims (1)

[Scope of Claim for Utility Model Registration] A take-up shaft for winding up occupant restraint webbing, a mainspring spring that applies rotational force in the webbing winding direction to the take-up shaft, and a take-up shaft provided on the take-up shaft. a ratchet wheel that rotates integrally; a pawl that engages with the ratchet wheel to prevent the take-up shaft from rotating in a webbing unwinding direction; a winding diameter sensing means, a portion of which receives the rotational force of the winding shaft through frictional force, and a second position which receives the rotational force in the webbing winding direction from a first position that maintains the pawl in a state in which the ratchet wheel is disengaged; a friction member that is pivotable between the first position and the second position and that allows the pawl to engage with the ratchet wheel; A webbing take-up device comprising: a turning angle regulating means for regulating a turning angle; and an arm coupled to the pawl and maintaining the pawl in a state in which the ratchet wheel is disengaged at the second position of the friction member.