JPS6216112Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a webbing lock device that is used in a seat belt device for protecting a vehicle occupant and locks the webbing for restraining the occupant in a vehicle emergency.

A webbing lock device used in a seat belt device is usually incorporated into a webbing retractor, and in the event of a vehicle emergency, an acceleration sensor engages with the lock ring, and this lock ring rotates relative to the webbing retractor shaft to activate the lock mechanism. When activated, the webbing unwinding rotation of the take-up shaft is stopped.

Due to the design of this winding device, it is necessary to change the mounting position of the acceleration sensor depending on the vehicle model.
If the relative mounting position tolerance between the acceleration sensor and the locking wheel is small, the acceleration sensor cannot be reliably engaged with the locking wheel even if the mounting position is slightly changed, reducing the degree of freedom in design.

Further, the winding device provided with the locking device must be installed at a predetermined angle of inclination in order to properly correspond to other vehicle parts within the vehicle body. When the axis of the acceleration sensor is tilted, it operates in the same manner as when the acceleration sensor is activated. Therefore, when changing the mounting angle of the winding device to the vehicle body, change the mounting position of the acceleration sensor on the winding device and always keep the acceleration sensor The axis of the must be vertical.

However, in conventional webbing lock devices, the relative position between the acceleration sensor and the locking wheel is limited, and if the acceleration sensor is moved relative to the locking wheel, the acceleration sensor may not engage with the locking wheel in a vehicle emergency, or the locking wheel may fail. There is a problem with the fully engaged state.

The present invention takes the above facts into account, and provides a webbing lock device that has a large relative mounting position tolerance between the acceleration sensor and the lock wheel, and allows the acceleration sensor to reliably engage with the lock wheel to operate the lock mechanism. is the purpose.

The webbing lock device according to the present invention has a spherical outer periphery facing the acceleration sensor of the lock ring, so that even when the acceleration sensor is mounted and moved relative to the lock ring along this convex curved surface, the distance between the lock ring and the acceleration sensor can be reduced. It is designed to be kept constant to cope with changes in the mounting angle of the winding device.

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

1 to 3 show a winding device 10 to which a webbing lock device according to the present embodiment is applied. This winding device 10 has a frame 12 fixed to a vehicle body 16 with mounting bolts 14.

A pair of legs 18 and 20 are provided from both sides of the frame 12 and extend parallel to each other, on which a winding shaft 22 is pivotally supported. This winding shaft 2
One end of an occupant restraining webbing 24 is wound in a layer around the center of the vehicle. Further, the inner end of the mainspring spring 26 is attached to the end of the winding shaft 22 that passes through the leg 20, and the outer end of this mainspring spring 26 is attached to the end that passes through the leg 20.
It is attached to a spring case 28 which is fixedly attached to the spring case 28. Therefore, the winding shaft 22 is biased in the winding direction of the webbing 24 (in the direction of arrow A in FIGS. 2 and 3).

A lock mechanism 30 is provided on the outside of the leg portion 18, and is configured to stop the webbing unwinding rotation of the take-up shaft 22 when activated. The locking mechanism 30 includes an internally toothed ratchet foil 32 secured to the outside of the leg 18 and a pair of lock plates 34, 36 corresponding to the ratchet foil 32.

A pair of lock plates 34 and 36 are attached to the winding shaft 22.
In a normal state, as shown in FIG. 3, the lock pawl 40 is separated from the internally toothed ratchet wheel 32 and the rectangular projection 38 of the winding shaft 22 is in contact with the outer periphery of the rectangular projection 38 formed at the end of the winding shaft 22. However, in the event of a vehicle emergency, the winding shaft rotates relative to the winding shaft and is driven by the rectangular protrusion 38, as shown in FIG. The webbing unwinding rotation of 22 is stopped.

From these lock plates 34, 36 the legs 1
The pin 42 protruding in the opposite direction to the lock ring 4
4 is housed in an elongated hole 46 (FIG. 6). This lock ring 44 is attached to a support shaft 48 that is attached to a rectangular protrusion 38 of the winding shaft and rotates together with the winding shaft.
A pair of lock plates 34,
36 are guided so as to be movable in opposite directions by the stroke of the elongated hole 46.

A torsion coil spring 50 is interposed between the lock ring 44 and the support shaft 48 to urge it in the direction of unwinding the webbing, and it rotates following the winding shaft 22 under normal running conditions of the vehicle. When the take-up shaft 22 suddenly rotates in the webbing unwinding direction, the torsion coil spring 50 is bent by inertia, causing a rotation delay, and the pair of lock plates 34 and 36 are engaged with the internally toothed ratch foil 32, thereby locking the lock mechanism. It's starting to work.

External teeth 52 are carved on the outer periphery of the lock ring 44 and correspond to the acceleration sensor 54.

This acceleration sensor 54 has an inertia ball 58 housed in a ball case 56 fixed to the leg 18, and when the vehicle acceleration reaches a predetermined value, the pole 60 is pushed up and engaged with the external teeth 52, resulting in locking. Rotation of the ring 44 in the webbing unwinding direction is stopped. The pole 60 is pivotally supported by a pin 62 to a frame 64, which is attached to the leg 18 via a ball case 56.

Here, the outer periphery of the lock ring 44 is a convex curved surface with a radius R ₁ as shown in FIG.
0 mounting angle change is supported. In other words, when the winding device 10 changes its attachment angle to the vehicle body while the acceleration sensor 54 is attached to the leg portion 18 as shown in FIG. It will mesh with 52. However, in this embodiment, since the outer periphery of the locking wheel 44 is spherical, the acceleration sensor 54 is
Even if the acceleration sensors 54A and 54B shown in the figure are changed to be concentric with the convex curved surface of the locking wheel 44 under the radius _R2 , the pawl 60 can be appropriately engaged with the external teeth 52 in the event of a vehicle emergency.

In order to attach the acceleration sensors 54A, 54B to the leg portion 18, ball cases 56 having different protrusion amounts from the leg portion 18 may be used.

In addition, since the external teeth 52 corresponding to the pole 60 have a convex curved surface, the pole 60 may be damaged due to manufacturing errors, assembly errors, etc.
Even if the position of 0 shifts slightly, the meshing relationship with the external teeth 52 does not change.

In this embodiment configured in this way, the occupant can unwind the webbing 24 from the take-up shaft 22 and put it on, and the lock mechanism 30 can be attached when the vehicle is normally running.
The driver is not activated, so the driver can change the driving position at will.

When the vehicle is in an emergency situation such as a collision, the acceleration sensor 54 engages the pawl 60 with the external teeth 52, so that the locking wheel 44 is stopped from rotating in the webbing unwinding direction. At the same time, the webbing 24 rapidly rotates the take-up shaft 22 in the take-up direction due to the movement of the occupant in the collision direction, so the take-up shaft 22 and the lock ring 44 cause relative rotation, resulting in the fifth As shown in the figure, the pair of lock plates 34, 36 mesh with the internally toothed ratchet wheel 32, and the webbing unwinding rotation of the winding shaft 22 is stopped.

Therefore, the occupant is reliably restrained by the webbing 24 and safety is ensured.

Note that in this winding device 10, the lock ring 44 lags in rotation relative to the winding shaft 22 even when the winding shaft 22 rapidly unwinds the webbing, so even if the acceleration sensor 54 fails, the lock mechanism 30 can be operated.

FIG. 8 shows a lock ring 44 used in a second embodiment of the present invention, in which the radius of curvature _R1 of the outer periphery is smaller than that of the previous embodiment.

Therefore, in this embodiment, the relative variation between the acceleration sensor and the locking wheel can be made large, and the winding device can also be installed at a large inclination to the vehicle body.

It should be noted that the present invention is not limited to the lock mechanism 30 and acceleration sensor 54 described above, but it is of course possible to use lock mechanisms and acceleration sensors of other structures.

As explained above, in the webbing lock device according to the present invention, the outer periphery of the lock ring is made spherical, so even if the mounting position of the acceleration sensor with respect to the lock ring is changed, the acceleration sensor can be reliably engaged with the lock ring. Has excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a winding device to which a first embodiment of the webbing lock device according to the present invention is applied;
Figure 2 is the left side view of Figure 1, and Figure 3 is the left side view of Figure 1.
4 is an exploded perspective view showing the main parts of the lock mechanism, FIG. 5 is a side view corresponding to FIG. 3 showing the operating state of the lock mechanism, and FIG. 6 is a view corresponding to FIG.
FIG. 7 is an enlarged view of the main part of FIG. 1, and FIG. 8 is a sectional view corresponding to FIG. 7 showing the locking wheel used in the second embodiment of the present invention. . 10... Winding device, 22... Winding shaft, 24...
Webbing, 30... Lock mechanism, 32... Internal tooth ratchet foil, 34, 36... Lock plate, 44... Lock ring, 52... External tooth, 54...
Acceleration sensor, 58...Inertia ball, 60...
Pole.

Claims (1)

[Claims for Utility Model Registration] (1) The acceleration sensor engages with the lock wheel, and the lock wheel rotates relative to the webbing take-up shaft to operate the lock mechanism and stop the webbing unwinding rotation of the take-up shaft. In the webbing lock device,
A webbing lock device characterized in that the outer periphery of the lock wheel facing the acceleration sensor is formed into a spherical surface so that the gap between the lock ring and the acceleration sensor is maintained constant even when the mounting angle of the acceleration sensor is changed. (2) The webbing lock device according to claim 1, wherein the lock ring is provided with external teeth corresponding to a pole of an acceleration sensor. (3) The lock ring is pivotally supported on the take-up shaft, and rotates relative to the take-up shaft due to rapid webbing unwinding rotation of the take-up shaft to operate the lock mechanism. A webbing lock device according to any one of scope 1 or 2.