JPH0735796Y2 - Webbing drive device for seat belt device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a webbing drive device for a seat belt device that drives an occupant restraining webbing via a wire to automatically attach or detach the occupant to the occupant.

[Prior Art] As a seatbelt device for automatically mounting or dismounting a webbing on an occupant after a passenger has boarded, an automatic seatbelt device for driving the webbing by a webbing drive device has been proposed.

As a webbing drive device, there is a webbing drive device that drives the webbing in the vehicle front-rear direction via a wire. In this type of webbing drive device, a drum is rotated by the driving force of a motor, and a wire is wound around this drum or sent out from the drum and guided by guide means arranged in the vehicle front-rear direction so that the webbing moves in the vehicle front-rear direction. It is designed to drive.

In this drive device, the drum around which the wire is wound is entirely covered with the cover, and the wire is stored inside the cover when the drum is wound around the drum. The cover is provided with a wire passage opening through which a wire wound on the drum or sent from the drum passes. The wire is sent from the passage opening to the drum or wound on the drum.

An edge portion of the wire passage opening provided on the cover is extended in the wire feeding direction to form an extension portion. A wire is sent out from this extending portion and inserted into a guide means arranged along the vehicle front-rear direction.

[Problems to be Solved by the Invention] However, in the above-described webbing drive device, when the wire is unwound from the drum, the wire to be fed intermittently abuts the inner wall of the cover, and a sound is generated, which causes discomfort to the passenger. There is a problem of giving.

That is, the outermost wire wound on the drum in a spiral shape and positioned at the end of the drum is rotated by the drum,
When the wire is fed from the cover passage opening in the driving direction, the wire is slid on the inner wall surface of the cover away from the outer periphery of the drum and driven to be fed out from the passage opening. However, the wire sent out from the inside of the cover is given a compressive load due to the sliding resistance of the guide means, so that the wire is buckled inside the cover and deformed in the same direction as the axial direction of the drum. If the wire is further fed with this buckling occurring, the wire will move in the opposite direction to the direction deformed by the buckling, and
It contacts the inner wall of the cover, especially the inner wall facing the end face of the drum, and a so-called dance phenomenon (bounce) occurs to generate sound. If this dance phenomenon occurs intermittently due to the feeding of the wire, it becomes an intermittent sound, which gives an occupant an uncomfortable feeling.

In consideration of the above facts, the present invention has an object to provide a webbing drive device for a seat belt device, which can feed a wire wound around a drum from the inside of the cover without buckling at the time of feeding the wire.

[Means for Solving the Problems] The present invention relates to a webbing drive device for a seat belt device, which winds or feeds a wire by rotating a drum by a driving means to attach or detach an occupant webbing. A cover that covers the drum and a wire that is formed in an arcuate shape on the inner peripheral wall of the cover and that is separated from the drum by restricting the movement of the wire in a direction parallel to the rotation axis of the drum, the opening surface of which faces the rotation axis of the drum. And a guide groove for guiding in the feeding direction.

[Operation] In the present invention having the above-described configuration, the wire fed out by the rotation of the drum and separated from the drum is guided into the arc-shaped guide groove formed on the inner peripheral wall of the cover and fed out from the inside of the cover. The fed wire is released from the occupant by driving the webbing. Even if a compressive load is applied to the wire due to sliding resistance or the like, the guide groove restricts the movement of the wire in the cover in a direction parallel to the rotation axis of the drum. Since it does not bend in parallel directions and does not buckle, so-called dance phenomenon does not occur.

As described above, in the present invention, when the wire is fed from the drum, the wire does not buckle and intermittently come into contact with the cover, so that no sound is generated and the occupant does not feel discomfort.

[Embodiment] FIG. 4 shows a webbing drive device according to an embodiment of the present invention.
An automatic seat belt system in which 10 is used is shown.

In this automatic seat belt device, a webbing 16 is automatically attached to an occupant 14 sitting on a seat 12. One end of the webbing 16 is wound up by a winding device 18 attached to a substantially central portion of the vehicle. The winding device 18 has a built-in inertia lock mechanism for stopping the pulling-out of the webbing 16 when the vehicle is decelerated.

A slider 20 is attached to the tip of the webbing 16 pulled out from the winding device 18. The slider 20 is guided along a roof side rail 22 of the vehicle and guided by a guide rail 24 laid in the front-rear direction of the vehicle. One end of a wire 26 (shown in FIG. 1) is connected to the slider 20, and the slider 20 has a center pillar 28.
By the webbing drive device 10 provided in the middle part of
It is configured to move in the vehicle front-rear direction along the guide rail 24 via the wire 26. When the slider 20 is located at the rear portion of the guide rail 24 in the vehicle, the webbing 16 is attached to the occupant 14 as shown in FIG. 4, and reaches the front end of the guide rail 24 as shown by an imaginary line. In the closed state, the occupant 14 can remove the webbing 16 from the occupant. The wire 26 is tightly accommodated in the tube 30 (see FIG. 2) disposed between the end of the guide rail 24 and the webbing drive device 10 between the slider 20 and the webbing drive device 10 and is lengthened. It is supposed to be movable in any direction.

The webbing drive device 10 is provided with a base plate 32 as shown in FIGS. 1 and 2. The base plate 32 has a circular hole 32A formed substantially in the center thereof and three leg plates 32B formed at the peripheral edge thereof by bending. These leg plates 32B
The front end of the is fixed to the center pillar 28 with a bolt 34 via a washer 35.

At the center of the base plate 32,
Gear box 36 is bolted between 32 and center pillar 28.
It is attached through 38. As shown in FIG. 2, a motor 40 is attached to the gear box 36, and a rotary shaft 42 is rotatably provided upright.

The motor 40 is connected to a switch (not shown) that detects a boarding / alighting operation of the occupant 14, and is operated when the occupant 14 gets on / off. As shown in FIG. 1, a worm gear 44 is coaxially attached to the output shaft 40A of the motor 40, and the rotary shaft 42 can be rotated via the worm gear 44 and a worm wheel 46 meshing with the worm gear 44.

The rotary shaft 42 penetrates through the circular hole 32A of the base plate 32 and has a tip portion protruding from the base plate 32 toward the center of the vehicle compartment.

On the other hand, a cover 50 is attached to the side of the base plate 32 opposite to the gear box 36 via a screw 48. The cover 50 is housed in the cover 50 and is mounted between the outer drum 52, the inner drum 54, and the inner drum 54. Plates 56 are attached in sequence.

The cover 50 is made of synthetic resin, and as shown in FIG. 2, has a protrusion 50A extending tangentially from the side wall of the cover 50. A support portion 50C is formed on the projecting portion 50A, the tip end portion of the tube 30 is accommodated therein, and is fixed to the support portion 50C by a bracket 51. Therefore, the wire 26 is guided into the cover 50 via the support portion 50C.

In addition, ribs are radiated from the center of the outer surface of the cover 50.
A plurality of 58 are formed. This increases the rigidity of the cover 50.

Further, as shown in FIG. 1 and FIG. 3, a groove 60 is formed on the inner wall of the cover 50 at the feeding portion through which the wire 26 is fed. The groove 60 has an arc-shaped cross section so that the wire 26 can move along the inner wall of the cover 50. For this reason, the wire 26 is accommodated in the groove 60 at the time of sending out, the movement of the outer drum 52 in the axial direction is restricted, and the wire 26 is guided in the axial direction of the wire and sent out of the cover 50. The groove 60 is provided along the inner wall of the cover 50 for about half a circumference as shown in FIG.

Further, on the end surface of the cover 50, a hole 50B for supporting the screw 62 for guiding and moving the screw plate 56 in the axial direction is formed. Like the cover 50, the screw 62 is made of a synthetic resin, and a male screw 62A having a large pitch is engraved on the outer periphery from one tip portion to the center portion for screwing with the screw plate 56. The outer periphery of the other end of the screw 62 is a circular portion 62B that fits into the hole 50B, and a groove into which the retaining ring 63 is inserted is formed at the end. Also male screw 62
A flange portion 62C is formed between A and the circular portion 62B. The cover 50 and the screw 62 have a hole 50B and a circular portion 6
2B and the retaining ring 63, and the flange 62
C is for determining the axial insertion amount of the screw 62 in the cover 50 at that time. See also 62
Has a through hole 62D formed along the axial direction of the rotary shaft 4
2 is rotatably inserted.

The outer drum 52 is formed into a cup shape with a circular bottom plate portion 52A and an annular side plate portion 52B, a rectangular hole 53C is formed in the center of the bottom plate portion 52A, and the rectangular hole 53C is formed at the tip of the rotary shaft 42. The drive portion 42A having a rectangular cross section formed is fitted. Therefore, the outer drum 52 is rotated by the rotation of the rotary shaft 42.

The inner drum 54 is fixed to a bottom plate portion 52A in the outer drum 52 and is rotatable with the outer drum 52. The inner drum 54 is disk-shaped, and projections 54A having a substantially fan-shaped cross section are axially projected at three locations around the axis at substantially equal intervals.
A wire accommodating space for accommodating the wire 26 is formed between the protruding portion 54A and the side plate portion 52B of the outer drum 52.

The screw plate 56 is formed by punching out a metal plate, and has a large-diameter outer ring portion 56A and a smaller-diameter inner ring portion 5A.
6B and three connecting portions 56C that connect them at equal intervals are provided. Then, three fan-shaped holes 56D are formed between the connecting portions 56C adjacent to each other, and the above-mentioned protruding portions 54A of the inner drum 54 are loosely fitted in these fan-shaped holes 56D. The end of the wire 26 is locked to the screw ring plate 56 by a rivet 82 via a clamp 80 on the outer ring portion 56A.
Further, the inner ring portion 56B of the screw plate 56 is made thicker than other portions by fixing an annular member 84 made of synthetic resin, and a female screw 78 is engraved on the shaft core portion thereof to cover the cover 50. It is screwed to the screw 62 fixed to the.

Each time the rotating shaft 42 is rotated in the forward direction, the wire 26 is wound around the outer circumference of the inner drum 54, and the screw plate 56
Also, the wire 26 is moved in the axial direction by the diameter of the wire 26 and the wire 26 is tightly wound around the outer circumference of the inner drum 54.
Further, the distance between the outer drum 52 and the protruding portion 54A of the inner drum 54 in the wire accommodating space is set to be equal to or larger than the diameter of the wire 26 and less than twice the diameter thereof, so that the wire 26 is reliably delivered. It has become.

Next, the operation of this embodiment will be described.

When the occupant 14 is not seated on the seat 12, the slider 20 is positioned at the vehicle front end of the guide rail 24 and the webbing is performed.
16 is in the state shown by the imaginary line in FIG.

Therefore, the occupant 14 can easily sit on the seat 12 and occupy the occupant. When the occupant 14 is seated on the seat 12, a switch (not shown) detects this and the motor 40 rotates the rotating shaft 42 in the forward direction. As a result, the outer drum 52, the inner drum 54, and the screw plate 56 are normally rotated, and the wire 26 is spirally wound around the inner drum 54. As a result, the slider 20 is moved to the rear of the vehicle along the guide rail 24 via the wire 26, and the occupant 14 is automatically fitted with the webbing 16 as shown by the solid line in FIG.

When the vehicle decelerates, the winding device 18 stops pulling out the webbing 16, so that the occupant 14 is reliably restrained by the webbing 16.

When the occupant 14 gets off, the switch (not shown) detects this and the motor 40 rotates the rotating shaft 42 in the opposite direction. As a result, the outer drum 52, the inner drum 54, and the screw plate 56 are reversely rotated, and the wire 26 is sent out from the inner drum 54.

As a result, the slider 20 is moved to the front of the vehicle along the guide rail 24 via the wire 26, and the occupant 14 automatically dismounts the webbing 16.

When the wire 26 is sent out from the cover 50, the wire 26
Is separated from the drum and is accommodated in the groove 60 provided in the cover 50, and the movement of the outer drum 52 in the axial direction is restricted, so that the so-called bouncing phenomenon of the wire 26 may occur. Since it does not exist and does not intermittently contact the inner wall of the cover 50, no sound is generated. Ie inner drum
When the wire 26 wound around 54 is sent out, sliding resistance is generated in the tube 30 and a buckling load is received at the sending-out portion from the cover 50, but when sent out by the rotation of the inner drum 54, The wire 26 separates from the outer periphery of the inner drum 54 and is accommodated in the groove 60. This allows the groove 60
Since the wire 26 is housed inside and sent out from the inside of the cover 50, the outer drum 52 is prevented from being deformed in a direction parallel to the rotation axis 42 due to a buckling load.

As described above, in the present invention, since the wire 26 is fed while being housed in the groove 60 at the time of feeding, the wire 26 does not buckle in the cover 50 due to the resistance due to the sliding resistance, which allows the wire 26 to be attached to the inner wall of the cover 50. Since no contact is made intermittently, no contact noise is generated.

[Effect of the Invention] As described above, in the present invention, when the wire is fed from the cover, the wire can be fed from the drum without buckling, so that the wire does not come into contact with the cover intermittently. It has an excellent effect that no contact noise is generated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an assembled state of a webbing drive device to which the present invention is applied, taken along line I-I in FIG.
2 is an exploded perspective view, FIG. 3 is a perspective view showing the inside of the cover, and FIG. 4 is a side view of a seat belt device using a webbing drive device as seen from the side of the vehicle. 10 ... Webbing drive, 14 ... Crew, 16 ... Webbing, 26 ... Wire, 50 ... Cover, 52 ... Outer drum, 54 ... Inner drum, 60 ... Groove.

Claims (1)

[Scope of utility model registration request] 1. A webbing drive device for a seat belt device, which winds or feeds a wire by rotating a drum by drive means to attach or detach the webbing to an occupant, the cover covering the drum, and the cover. A guide groove that is formed in an arcuate shape on the inner peripheral wall of the drum and has an opening surface that faces the rotation axis of the drum and restricts movement of the wire in a direction parallel to the rotation axis of the drum and guides the wire detached from the drum in the feeding direction. And a webbing drive device for a seat belt device.