JP3022253B2 - Webbing take-up device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a webbing winding device used for a seat belt device of a vehicle.

[0002]

2. Description of the Related Art For example, in a webbing take-up device of a three-point type seat belt device, a frame is formed in a U-shape by a back piece and a pair of opposing leg pieces.
The winding shaft is rotatably extended. The winding shaft has a slit hole along the axial direction. One end of the webbing is inserted into the slit hole to prevent the webbing from coming off, and the webbing is wound around the winding shaft. The frame of the winding device is bolted to the lower portion of the vehicle body side wall so that the axial direction of the winding shaft is in the vehicle front-rear direction. The other end of the webbing extends upward from the take-up shaft, passes through a shoulder through anchor (slip joint) at the upper part of the vehicle body side wall, and is folded back downward to be locked by a lap anchor at the lower part of the vehicle body side wall.

[0003] A tongue plate is inserted between the shoulder through anchor of the webbing and the wrap anchor, and the tongue plate is engaged with a buckle on the side of a vehicle seat so that the webbing wraps between the wrap anchor and the tongue plate. A webbing portion is provided, and a portion between the tongue plate and the shoulder through anchor is a shoulder webbing portion, which is mounted on an occupant.

Normally, the webbing can be freely pulled out and wound up, but when the vehicle is suddenly decelerated, the locking means prevents the winding shaft from rotating in the webbing pulling-out direction, thereby preventing the webbing from being pulled out. It is designed to be restrained by webbing.

[0005] Here, a protector is fitted into the upper portion of the frame of the winding device so as to straddle between the leg pieces, and an insertion hole through which the webbing is inserted is formed in the protector, so that the webbing is pulled out and wound. Guided.

[0006]

By the way, the webbing has a large winding diameter when the winding amount is large, and conversely, has a small winding diameter when the winding amount is small, and the winding diameter depends on the winding amount of the webbing. Are different. The insertion hole extends from the maximum winding diameter to the minimum winding diameter, and the clearance in the thickness direction of the webbing has a margin so that the webbing exiting from the winding shaft passes straight through the insertion hole and pulls out smoothly. It is formed.

However, if the distance is large, the webbing may be shifted in the width direction during movement.

On the other hand, when the insertion hole is narrowed, the webbing moves in the thickness direction in accordance with the diameter of the webbing wound around the winding shaft, so that the webbing comes into contact with the inner periphery of the insertion hole. If the frictional force due to this contact is large, a force for detaching the protector in which the insertion hole is formed is generated, so that the protector must be firmly attached.

The present invention has been made in consideration of the above-described circumstances, and has as its object to provide a webbing winding device that winds up a webbing in an orderly manner and suppresses an increase in frictional force between a guide member and the webbing.

[0010]

According to a first aspect of the present invention, there is provided a webbing having a frame mounted on a vehicle body and one end of a webbing for restraining an occupant being rotatably supported by the frame. A take-up shaft, a guide member having an insertion hole attached to the frame, through which the webbing is inserted, and which serves as a guide for drawing and winding the webbing to the take-up shaft; and The webbing is provided at a part of the webbing, and is located at a widthwise end of the webbing and the webbing with respect to the winding shaft.
On the tangential extension of the maximum winding diameter where the winding diameter is large
Position, and a narrow portion in which the webbing thickness dimension is formed narrowly, provided continuously to the narrow portion, and the winding shaft as well as the corresponding position in the widthwise central portion of the webbing
The tangent of the minimum winding diameter where the winding diameter of the webbing is smaller.
A wide portion which is located on the extension line in the direction of extension, has a wide dimension in the thickness direction of the webbing, and serves as a receiving portion for the webbing which moves in the thickness direction when the webbing tension is increased.

[0011]

According to the above construction, the webbing is pulled out according to the occupant's physique and is mounted on the occupant. After the mounting is released, the webbing is wound up. When pulling out and winding up the webbing, the webbing moves through the insertion hole of the guide member. The insertion hole prevents deformation such that the narrow portion is located at the end portion in the webbing width direction and the end portion in the webbing width direction has a wavy shape, and also prevents deviation in the webbing width direction.

Since the webbing is prevented from moving in the thickness direction at the narrow portion of the insertion hole, the webbing attempts to move in the thickness direction as the winding diameter on the winding shaft changes depending on the amount of webbing pulled out. Then, the longitudinal direction of the webbing is bent at the insertion hole. Here, the webbing tension increases when the webbing is fully pulled out or when the winding shaft is locked, but the webbing is deformed at the center in the width direction due to the increase in the tension, and the webbing moves in the thickness direction and spreads. Get into the club. For this reason, a large frictional force does not act between the inner circumference of the insertion hole and the webbing even when the webbing is moved by winding or drawing.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A webbing winding device according to an embodiment of the present invention will be described with reference to FIGS. In the figure, the arrow FR indicates the front of the vehicle, the arrow RE indicates the rear of the vehicle, and the arrow W indicates the vehicle width direction.
The upper part of the vehicle is indicated by an arrow UP.

As shown in FIG. 1, the frame 12 is formed in a U-shape with a back piece 13 and a pair of leg pieces 14 and 16 facing each other, and is fixed to a lower part of a side wall of the vehicle body with a bolt 17. The leg pieces 14 and 16 are disposed in front of and behind the vehicle and face each other, and a winding shaft 18 extending in the vehicle front-rear direction extends between the leg pieces 14 and 16.

The winding shaft 18 has supporting shafts 20 and 22 at both ends. One support shaft 20 is supported by a sensor cover 24 attached to the outer surface of the leg piece 14, and the other support shaft 22
Is pivotally supported by a mainspring spring cover (not shown) attached to the outer surface of the leg piece 16. Thereby, the winding shaft 18
Is rotatable about the support shafts 20 and 22. The winding shaft 18 has a slit hole 23 formed along the axial direction.
One end of the webbing 25 is inserted and locked therein, thereby preventing the webbing 25 from being detached. Slit hole 23
The webbing 25 is wound around the winding shaft 18 and the webbing 25 is drawn or wound with the rotation of the winding shaft 18 (the webbing pulling-out direction is indicated by an arrow A).

A mainspring (not shown) fitted to the support shaft 22 is accommodated in the mainspring spring cover. The mainspring moves the winding shaft 18 in the webbing winding direction (arrow A).
To the opposite direction). That is, the webbing 25 is urged toward the winding side.

A V gear 26 is provided inside the sensor cover 24.
The V gear 26 is fitted to the outer peripheral surface of the support shaft 20 and is supported coaxially with the take-up shaft 18, and has a first relative rotational position with respect to the take-up shaft 18 (see FIG. 2). Position) and a second relative rotational position (the position shown in FIG. 3). On the outer periphery of the V gear 26, engagement teeth 30 are formed.
An acceleration sensor 34 is provided in the sensor cover 24 corresponding to the outer periphery of the V gear 26.
Is provided with a ball 36 which inertially moves forward of the vehicle in response to acceleration due to rapid deceleration of the vehicle, and a V pawl 40 which rotates upward (in the direction of arrow B in FIGS. 2 and 3) as the ball 36 inertially moves. Prepare. V pawl 40 is V gear 26
2 (shown in FIG. 2), and is engaged with the engaging teeth 30 by the upward rotation of the V pawl 40 (shown in FIG. 3). The engagement between the V pawl 40 and the engagement teeth 30 of the V gear 26 prevents the V gear 26 from rotating in the webbing pull-out direction.

As shown in FIG. 2, the winding shaft 1 of the V gear 26
8, a torsion spring 42 is provided, a central portion 44 of the torsion spring 42 is curved in an arc around the support shaft 20, and one end 46 of the torsion spring 42 is It is bent toward the end face of the gear 26 and is locked in a locking hole 48 formed in the end face of the V gear 26, and the other end 50 of the torsion spring 42 faces the end face of the V gear 26. The winding shaft 18 is bent and penetrated through the through hole 52 formed on the end face of the V gear 26, and is locked in the locking hole 54 formed on the end face of the winding shaft 18. The torsion spring 42 normally positions the V gear 26 and the take-up shaft 18 at the first relative rotation position, and moves the V gear 26 to the take-up shaft 18.
Rotate to follow. When the take-up shaft 18 rotates in the webbing pull-out direction in a state where the rotation of the V gear 26 in the webbing pull-out direction is stopped, the other end 50 of the torsion spring 42 is moved into the through hole 52 by the rotational force of the wind-up shaft 18. Is moved in the circumferential direction toward the diameter reducing side of the torsion spring 42, and the winding shaft 18 is
V gear 2 ahead in the webbing withdrawal direction against the urging force of
A second relative rotational position is obtained for 6.

As shown in FIG. 2, the V gear 26 and the winding shaft 1
8, a lock plate 55 is provided. The lock plate 55 includes a fork-shaped recess 56 formed in a part of the outer periphery, and the winding shaft 1 corresponds to the recess 56.
A columnar projection 58 is formed on the end face of the projection 8 so as to protrude, and the projection 58 is engaged with the recess 56. The lock plate 55 has a concave portion 60 on the opposite side to the concave portion 56 for passing a hub 26A serving as a support shaft of the V gear 26. On both left and right sides of the concave portion 60, a pair of guide pins 62 for the V gear 26 are provided. It protrudes toward the end face. A guide recess 64 is provided in the end face of the V gear 26 corresponding to the guide pin 62.
Are engaged in the guide recess 64. A plurality of lock claws 66 are also formed on the outer periphery of the lock plate 55, and corresponding to the lock claws 66, a lock tooth 68 constituted by internal teeth coaxially with the winding shaft 18 is provided on the leg piece 14. It is formed. The lock teeth 68 together with the lock plate 55 constitute locking means.

The guide recess 64 is formed to be long in a direction perpendicular to the axial direction of the V gear 26, and when the take-up shaft 18 and the V gear 26 are in the first relative rotation position and rotate integrally, the guide recess 64 is provided. The pin 62 is located at one end of the guide recess 64, and the lock plate 55 rotates together with the winding shaft 18 and the V gear 26,
The lock pawl 66 is separated from the lock teeth 68. When the winding shaft 18 rotates relative to the V gear 26 from the first relative rotation position to the second relative rotation position prior to the webbing withdrawal direction in a state where the rotation of the V gear 26 in the webbing withdrawal direction is prevented. , The lock plate 55 has the winding shaft 18 and the V
It relatively moves with any of the gears 26. That is, the concave portion 56 of the lock plate 55 is pushed by the convex portion 58 of the winding shaft 18 to move, and the guide pin 62 is moved by the guide concave portion 6.
4 to the other end. Winding shaft 18 and V gear 2
6 reaches the second relative rotation position, the lock claws 66 of the lock plate 55 are locked with the lock teeth 68 as shown in FIG.
Is engaged. By this engagement, the rotation of the winding shaft 18 in the webbing pull-out direction is prevented, the webbing 25 is pulled out, and the occupant is restrained.

As shown in FIG. 1, an inertia plate 78 is provided between the V gear 26 and the sensor cover 24.
The inertia plate 78 is formed in an annular shape having a through hole 80 through which the support shaft 20 of the winding shaft 18 passes, and a pin protruding from an end surface of the V gear 26 on an eccentric axis line eccentric with the center of the support shaft 20. The shaft 82 has a pin hole 8 formed in the inertia plate 78.
4 and supported by the V gear 26 so as to be rotatable about a pin shaft 82.

A coil spring 86 is provided between the inertia plate 78 and the V gear 26. One end of the coil spring 86 is locked by a locking projection 88 formed on the inertia plate 78, and the other end is fixed. The V gear 26 is locked by a locking projection 90 formed on the end face. In addition, a part of the outer periphery of the inertia plate 78 is cut out, and a stopper 95 is provided on the end face of the V gear 26 so as to correspond to the notch 93, and as shown in FIG. When the stopper 95 is urged by the force to abut the notch 93, the inertia plate 78 can normally rotate integrally with the V gear 26.

On the outer periphery of the inertial plate 78, a W pawl 92 is provided.
Is formed, and the sensor cover 24 is provided with a W tooth 94 (FIG. 1) which is formed as an internal tooth on the coaxial circumference of the winding shaft 18 so as to face the outer circumference of the inertia plate 78 at the first axial position of the V gear 26. Reference). When the webbing 25 is rapidly pulled out and an acceleration is applied, the inertia plate 78 is delayed with respect to the rotation of the V gear 26, rotates relatively to the V gear 26 around the pin shaft 82, and the W pawl 92 Projecting outward from the position where the teeth 94 are disengaged from the teeth 94 and engaging with the W teeth 94, the rotation of the V gear 26 in the webbing withdrawing direction is prevented. Since the rotation of the V gear 26 in the webbing withdrawal direction is prevented, the winding shaft 18 and the V gear 26
As shown in FIG. 3, the lock plate 55 moves relative to both the take-up shaft 18 and the V gear 26, thereby locking the motor. The pawl 66 is engaged with the locking tooth 68.

A protector 100 as a guide member is fitted into the upper end of the frame 12. Protector 1
Reference numeral 00 denotes a long rectangular plate extending between the two leg pieces 14 and 16 along the back piece 13.

A U-shaped engaging recess 12A is formed in the frame 12 on the side of the spine 13 at the upper edge of the leg pieces 14, 16 and an engaging hole is formed substantially at the center of the upper part of the spine 13 (in the direction of the arrow UP). 12C is formed. Correspondingly, the protector 100 has a locking projection 102 formed thereon and a locking projection 104 projecting therefrom. By inserting the locking projection 102 into the locking recess 12A so as to be pushed from the back piece 13 side, and inserting the locking projection 104 into the locking hole 12C,
The protector 100 is fitted.

As shown in FIG. 5, the protector 100 has an insertion hole 106 formed along the longitudinal direction (the directions of arrows FR and RE). The webbing 25 is inserted into the insertion hole 106, and when the webbing 25 is pulled out to the winding shaft 18, the amount of movement of the webbing 25 in the vehicle front-rear direction (arrows FR and RE directions) during winding is limited, so that the webbing 25 is moved. It is guided by the winding shaft 18.

The portions of the insertion holes 106 corresponding to the ends in the width direction of the webbing 25 are defined as narrow portions 108A and 108B. The narrow portions 108A and 108B are arranged such that the dimension in the thickness direction of the webbing 25 is slightly wider than the thickness of the webbing. D1. That is, the narrow portions 108A and 108B are brought into abutment with the left-right surface or the front-rear surface of the widthwise end of the webbing 25 at the time of winding, and the webbing 25 is deformed such that the end portion becomes corrugated. 25 Prevents displacement in the width direction.

The portion corresponding to the center of the insertion hole 106 in the width direction of the webbing 25 is a wide portion 110, and the wide portion 11
0 is an interval D2 where the dimension in the thickness direction of the webbing 25 is large. That is, the wide portion 110 is a receiving portion for the webbing 25 that moves in the thickness direction when the webbing 25 tension is increased.

The narrow portions 108A and 108B are formed by webbing 2
5 is located on an extension of the tangential direction when the winding amount is large and the winding diameter of the webbing 25 is the maximum winding diameter (see the arrow LA in FIG. 6). As shown in FIG.
Is extended to the tangential extension in the case where the winding amount of the webbing 25 is small and the winding diameter of the webbing 25 is small (see the arrow LB in FIG. 6).

As shown in FIG. 5, the wide portion 110 and the narrow portion 1
08A and 108B, a continuous hole edge is formed in an arc shape when viewed from above.

The distal end of the webbing 25 reaches an occupant mounting portion via an anchor member such as a slip joint (not shown).

Next, the operation of this embodiment will be described. The webbing 25 is pulled out according to the occupant's physique and is attached to the occupant. After the attachment is released, the webbing 25 is wound up. The webbing 25 is pulled out and wound up through the protector 100. That is, when the webbing 25 is pulled out,
The webbing 25 is guided out of the winding shaft 18 through the insertion hole 106 of the protector 100. Webbing 25
Is wound, the webbing 25 is guided by the winding shaft 18 through the insertion hole 106 of the protector 100. In the insertion hole 106, the narrow portions 108 </ b> A and 108 </ b> B correspond to the ends in the width direction of the webbing 25 to prevent waving at the ends in the width direction of the webbing 25, and prevent the webbing 25 from being offset in the width direction. it can.

On the other hand, when the webbing 25 is gradually pulled out and the winding amount decreases, the winding diameter of the winding shaft 18 decreases. The solid line state in FIG. 6 indicates the minimum winding on the winding shaft 18, and the imaginary line state indicates the maximum winding on the winding shaft 18. As described above, the movement trajectory of the webbing 25 from the protector 100 to the slip joint (not shown) due to the change in the diameter of the webbing 25 wound on the winding shaft 18 tends to be displaced in the thickness direction (the direction of the arrow W) (dimension H). As a result, the intermediate portion of the webbing 25 is always bent at the protector 100 or in a certain winding state (see the webbing 25A in FIG. 6).

Here, the webbing tension increases when the webbing 25 is fully pulled out or when the winding shaft 18 is locked, and as shown in FIG. The central portion in the width direction is deformed, moves in the thickness direction, and enters the wide portion 110. For this reason,
A large frictional force does not act between the inner circumference of the insertion hole 106 and the webbing 25 even when the webbing 25 is wound or pulled out, so that the webbing 25 is wound up or pulled out smoothly. If the tension of the webbing 25 decreases,
The webbing 25 returns to the flat plate shape again, and is in the state of the imaginary line in FIG.

In this embodiment, the webbing 25 is configured to be substantially straight without being bent at the protector 100 in the maximum winding state of the webbing 25 on the winding shaft 18 (in the imaginary line state in FIG. 6). But the webbing 25
The webbing 25 may always be bent at the protector 100 regardless of the winding amount of the webbing 25 depending on the arrangement of the slip joint at the upper part of the webbing.

When the winding shaft 18 is provided with a flange for guiding the winding of the webbing 25 at both ends in the axial direction or a lock gear, the winding of the webbing 25 is guided by these flanges. Thus, even with a winding device without a flange or a lock gear, it is possible to appropriately wind the webbing 25 without offset in the width direction.

[0037]

According to the webbing take-up device of the present invention,
The webbing is wound up neatly, and an increase in frictional force between the guide member and the webbing is suppressed.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing one embodiment of a webbing take-up device of the present invention.

FIG. 2 is a side view showing the locking means of the webbing take-up device according to the present embodiment and viewed from the direction of an arrow RE shown in FIG. 1 in the axial direction of the take-up shaft.

FIG. 3 is a side view corresponding to FIG. 2 and showing an operating state of the lock unit according to the embodiment.

FIG. 4 is a side view corresponding to FIG. 2, showing an operation state of a W pawl of the webbing take-up device according to the embodiment.

FIG. 5 is a plan view of a main part of the webbing take-up device according to the present embodiment, showing the protector mounted on the frame of FIG. 1;

6 is a cross-sectional view taken along the line VI-VI of FIG. 5, illustrating a main part of the webbing take-up device according to the present embodiment.

[Explanation of symbols]

 12 frame 18 take-up shaft 25 webbing 100 protector (guide member) 106 insertion hole 108A narrow portion 108B narrow portion 110 wide portion

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60R 22/18-22/26 B60R 22/34

Claims (3)

(57) [Claims] A frame mounted on a vehicle body, a winding shaft rotatably supported by the frame, one end of a webbing for restraining an occupant being taken up by the webbing, and a frame mounted on the frame; A guide member provided with an insertion hole through which a webbing is inserted and used as a guide for drawing and winding the webbing to the winding shaft; provided at a part of the insertion hole, corresponding to a width direction end of the webbing; And the wafer with respect to the winding shaft
The winding diameter of the bing is large.
And a narrow portion formed in the thickness direction of the webbing so as to be narrow, and a narrow portion provided continuously with the narrow portion and corresponding to a center portion of the webbing in the width direction and a front portion with respect to the winding shaft.
A tangential extension of the minimum winding diameter that reduces the winding diameter of the webbing
A webbing take-up device having a wide portion which is located at a corresponding position on the upper side, has a wide dimension in the thickness direction of the webbing, and serves as a receiving portion for the webbing which moves in the thickness direction when the webbing tension increases. (2) The narrow portion and the wide portion are continuously formed in an arc shape.
The webin of claim 1, wherein the webin is formed.
Rewinding device. (3) The insertion hole of the guide member is formed.
A portion to be formed is the rectangular plate shape.
3. The webbing winding device according to 1 or 2.