JPH0630574Y2 - Seatbelt pre-loader device - Google Patents

Description

[Detailed Description of the Invention] <Industrial field of application> The present invention is designed to minimize the forward movement of an occupant by automatically winding in the slack of the seat belt in the event of a collision accident so as to tension the slack. Seat belt pre-loader device.

<Prior Art> For example, a seat of an automobile is provided with a seat belt for restraining the movement of the occupant in order to prevent the occupant from being thrown forward in the event of a collision accident. In some cases, a retractor device with an emergency automatic locking device (hereinafter abbreviated as ELR device) that locks the seat belt retracting shaft only during a collision without restricting the operation during driving is provided.

This ELR device is generally of a type that locks the take-up shaft within an extremely short time by detecting acceleration at the time of collision or sudden extension of the seat belt, and therefore, especially in the initial state. When the amount of slack in the seat belt is large, the restraining force of the occupant may be insufficient.

Based on this point of view, for example, Japanese Examined Patent Publication No. 53-2157
No. 4 or Japanese Utility Model Publication No. 53-25943 discloses a preloader device that tensions the seat belt by rapidly winding the end portion of the seat belt at the time of a collision.

Since it is necessary to instantaneously wind the belt in such a preloader device, a drive source that can instantaneously obtain a large output, such as explosives such as explosives, is suitable.

<Problems to be solved by the device> However, if the explosive force of explosive powder is converted into a traction force such as a wire and transmitted to the traction mechanism of the seat belt, a large driving force rises momentarily at the time of explosion, This causes an inconvenience that a large shock is momentarily applied to the body when the seat belt is strained.

In view of such inconveniences of the prior art, a main object of the present invention is to provide a seatbelt preloader device capable of limiting a rapid rise of torque due to explosives and transmitting the torque to a seatbelt traction mechanism. To do.

<Means for Solving Problems> According to the present invention, there is provided such a driving means for generating driving force by releasing energy of explosives in response to a shock at the time of a vehicle collision, and the driving means. A wire to which a pulling force is applied by the means, one end of the wire is connected, and a pulley around which the wire is wound at a predetermined angle, and a seat belt winding means integrally connected to the pulley, A preloader device for tensioning a slack of a seat belt in a vehicle collision, wherein a wire winding radius of the pulley is
This is achieved by providing a seat belt preloader device characterized in that it is progressively increasing in the direction of rotation.

<Operation> In this way, it becomes possible to set the seat belt winding torque of the preloader device according to the driving force generation characteristics of the driving source that gives the pulling force to the wire, and when using, for example, explosives as the driving source. Also, the traction force applied to the seat belt can be appropriately suppressed.

<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a structure around a seat belt to which the present invention is applied, in which a seat belt 3 pulled out upward from an ELR device 2 fixed to a lower part of a center pillar 1 in a vehicle compartment is
After passing through the through ring 4 attached above the center pillar 1, it is extended downward and the end portion 6 is attached to the rear side surface of the seat 5. A tongue plate 7 is provided between the through ring 4 and the end portion 6 of the seat belt 3 so as to be movable along the seat belt 3.

After the occupant seated on the seat 5 pulls out the seat belt 3 from the ELR device 2, the tongue plate 7 is attached to the buckle 8 attached to the side surface of the seat opposite to the fixing point of the seat belt end portion 6. The seat belt 3 is stretched around the shoulders, chest and waist of the occupant.

Normally, in this state, the seat belt 3 is pulled out from the ELR device 2 through the through ring 4 with relatively little resistance, so that the upper body is relatively free to move. At the time of collision, E
The ratchet mechanism incorporated in the LR device 2 locks the winding shaft of the seat belt 3 and restrains the forward movement of the occupant.

By the way, the locking of the take-up shaft does not compensate for the slack of the seat belt 3 before the collision is sensed and the tightening of the seat belt 3 with respect to the take-up shaft. There are some cases. Therefore, according to the present invention, a preloader device, which will be described later, is provided near the seat belt feeding port of the ELR device 2.

As shown in FIG. 2, the housing 11 of the preloader device 10
Is formed by bending a metal plate, and side disks 12 and 13 made of synthetic resin having self-lubricating property are rotatably mounted in circular holes 11a and 11b formed on both side surfaces thereof, respectively.

The first side disc 12 has a circular hole 11a formed from the inside of the casing 11 such that a flange portion 12a formed outwardly in the radial direction on one side face of the side disc is brought into contact with the inner side face of the casing 11. A boss 14 that is inserted and protrudes outward in the axial direction at the center of the other side surface is projected to the outside of the housing 11. A pulley 15 is fixed to the boss 14 so as to rotate integrally with the first side disk 12, one end of which is connected to a drive source (not shown) in the groove of the pulley 15, and the other end of which is located at an appropriate position of the pulley 15. The pulling wire 16 fixed to the wire is wound.

The second side disk 13 is inserted into the circular hole 11b such that a flange 13a formed similarly to the first side disk 12 is brought into contact with the outer surface of the housing 11.

The inner surfaces of the side disks 12, 13 facing each other are engaged with recesses 12b, 13b engaging with both ends of the fixed clamp member 17 in the axial direction and a rotating shaft 19 formed at both ends of the movable clamp member 18 in the axial direction. Bearing hole 12c,
13c and 13c are respectively recessed so that when both side disks 12 and 13 are inserted into the housing 11, both clamp members 17 and 18 are sandwiched between the side disks. Further, the fixed clamp member 17 is fixed to both side discs 12 and 13, and the movable clamp member 18 is configured to be rotatable relative to both side discs 12 and 13 by its pivot shaft 19. The seat belt 3 whose one end is wound around the ELR device is usually inserted into the gap between the clamp members 17 and 18 so that the seat belt 3 can be unwound and wound.

The side plate 20 is attached to the side surface of the housing 11 via screws 20a so as to cover the outer surface of the flange 13a of the second side disk 13. The inner surface of the side plate 20 has a recess 20 slidably provided on the outer surface of the flange 13a in order to regulate the axial displacement of the second side disk 13.
b is recessed, and ratchet teeth 20c are engraved on the axially outer end surface.

At the center of the second side disk 13, a boss 21 is provided so as to project outward in the axial direction. A stopper plate 22 is axially displaceable along the boss 21 in order to regulate the rotation direction of the boss 21 by engaging with the ratchet teeth 20c.
Along with it, it is fitted so as to be rotatable. Further, the stopper plate 22 is provided between the spring retainer 23 fitted to the end of the boss 21 in the axial direction and the outer surface of the stopper plate 22.
4, the ratchet teeth 20c are pressed and urged.

As best shown in FIG. 3, the stopper plate 22 is provided with teeth 22a that mesh with the ratchet teeth 20c of the side plate 20. These both teeth 20c, 22
a is a serrated shape, and when the boss 21 rotates together with the stopper plate 22 in the direction of arrow A, the stopper plate 22 resists the pressing force of the coil spring 21 and extends in the axial direction along the tooth slope. Since it can be displaced outwardly, it does not hinder the rotation at all, but when a rotational force in the opposite direction to the above acts on the boss 21, the teeth 20c and 22a mesh with each other, and the rotation of the boss 21 is prevented. Will be blocked.

As well shown in FIG. 4, the fixed clamp member 17 and the movable clamp member 18 are arranged at positions facing each other such that the seat belt 3 is sandwiched between them in a non-contact manner.

The fixed clamp member 17 is formed by projecting two mountain-shaped protrusions on a columnar rod-shaped body, and the fixed clamp teeth 17a are formed by these protrusions. It is fixed between 12 and 13.

The movable clamp member 18 has a substantially semicircular cross section, and its outer peripheral contour is formed into a smooth curved surface. As described above, the rotary shafts 19 projecting from both ends in the axial direction are provided on both side disks 12, 13. It is pivotally attached to the bearing holes 12c and 13c.

The rotating shaft 19 is the seat belt 3 of the movable clamp member 18.
The center of rotation is provided at a position eccentric to the upper side in FIG. 4 along the seat belt 3 from the center of rotation of the side disks 12 and 13. ing. Further, movable clamp teeth 18a corresponding to the above-described clamp teeth 17a are formed on a portion of the surface of the movable clamp member 18 facing the seat belt 3 below the rotary shaft 19, and the fixed clamp teeth are formed. 17a
To be able to mesh with each other.

As shown by the broken line in FIG. 4, the pulley 15 is formed in a contour in which the pitch circle radius of the winding groove is smoothly gradually increased corresponding to the driving force characteristic generated by the driving source.
The wire 16 wound around is extended upward in FIG. 4 through the guide roller 16a and is connected to the drive source as described above. In the figure, 3a and 3b are guide rollers pivotally attached to the housing 11 to guide the seat belt 3.

Next, the operation procedure of the above embodiment will be described with reference to FIGS.

One end of the wire 16 wound around the pulley 15 is connected to a drive device (not shown) that uses explosive force such as explosives, and the drive device is an ELR device (not shown) of a known type. In conjunction with this, when the vehicle collides, the pulling force is instantly applied to the wire 16.

Normally, the fixed clamp member 1 is in the state shown in FIG.
7 and the movable clamp member 18 do not interfere with the seat belt 3 at all, and the seat belt 3 is freely drawn and wound.

When the collision is detected and the wire 16 is pulled in the direction of arrow B, the pulley 15 rotates in the direction of arrow C, and the end circle portion 18b of the movable clamp member 18 abuts on the seat belt 3. As a result, the movable clamp member 18 is pushed by the seat belt 3, tilts in the direction of the arrow D about the pivot shaft 19, and the seat belt 3 is caught between the clamp teeth 17a and 18a. At this time, the seat belt 3 is pulled by the end circle portion 18b in the direction of the arrow E (6th position).
Figure). The wire 16 is further pulled to move the movable clamp member 1
The end circular portion 18b of 8 further retracts the seat belt 3 (7th
Figure).

The seat belt 3 is engaged with both the clamp teeth 17a and 18a immediately after being unrolled from the ELR device, and the ratchet mechanism including the ratchet teeth 20c and the stopper plate 22 prevents the pulley 15 from rotating in the reverse direction. It is possible to apply a certain amount of tension to the seat belt 3 on the side that is extended from the device.

As described above, the radius of the pulley in the section to which the traction force is applied when the drive device is activated is small, and the winding torque is also relatively small (Fig. 5). Therefore, even when a drive source having a large instantaneous force such as explosive is used, it is possible to avoid the inconvenience caused by the sudden entrainment of force. Although the gas pressure decreases in the latter half of the explosion, the driving force due to the explosion can be averaged over the entire stroke because a relatively large traction force acts on the large diameter portion of the pulley (Fig. 7).

In the above embodiment, the explosive force of explosive was used as the traction drive source, but other than this, a drive device such as compressed air or spring means that can instantaneously obtain a large output is suitable. There is.

Further, since the structure shown in the above-mentioned embodiment generates the clamping force by the pressing force of the seat belt,
The tighter the binding force, the more tightly the seat belt is wound, and the seat belt can be reliably held.

<Effect of the Invention> As described above, according to the present invention, since the traction force can be changed according to the starting torque characteristic of the drive source, it is possible to avoid applying an excessive belt load to the occupant suddenly, and in particular, to prevent an explosion. When an object is used as the drive source, it is possible to reduce the starting torque and increase the torque in the latter half of the explosion, and it is possible to achieve a great effect in optimizing the belt load over the entire stroke.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a seat belt to which the present invention is applied. FIG. 2 is a plan view showing an embodiment of the present invention partially broken away. FIG. 3 is a partial view showing the reverse rotation preventing mechanism. FIG. 4 is a sectional view taken along the line IV-IV in FIG. 5 to 7 are explanatory views showing the operation of this embodiment. 1 ... Center pillar, 2 ... ELR device 3 ... Seat belt, 4 ... Through ring 5 ... Seat, 6 ... End 7 ... Tongue plate, 8 ... Buckle 10 ... Preloader device, 11 ... Cases 11a, 11b ... Circular holes 12, 13 ... Side disks 12a, 13a ... Flange 12b, 13b ... Recesses, 12c, 13c ... Bearing holes 14 ... Boss, 15 ... Pulley 16 ... Wire, 17 ... Fixed clamp member 18 ... Movable clamp member 17a, 18a ... Clamp teeth 19 ... Rotating shaft, 20 ... Side plate 20a ... Screw, 20b ... Recess 22c ... Ratchet tooth, 21 ... Boss 22 ... Stopper plate 22a ... Tooth, 23 ... Retainer 24 ... Coil spring

Claims (1)

[Scope of utility model registration request] 1. Driving means for generating driving force by releasing energy of explosives in response to a shock at the time of a vehicle collision,
A wire to which a traction force is applied by the drive means, a pulley to which one end of the wire is connected and the wire is wound at a predetermined angle, and a seat belt retracting means integrally connected to the pulley. A preloader device for tightening the slack of a seatbelt in a vehicle collision, wherein the wire winding radius of the pulley is gradually increased in the rotation direction.