JPH1159330A - Seatbelt retractor and its spool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit a webbing to be firmly fastened to a spool of the type in which a torsion bar is passed through an inner hole. SOLUTION: A spool 50 has an inner hole through which a torsion bar 54 is passed, and a first slit 124 and a second slit 126 which extend parallel to each other in the direction of a hypotenuse on a cross section perpendicular to the axis of the inner hole are provided. The ends of a webbing 130 are passed through the slits 124, 126. The ends of the webbing 130 are folded back and sewn together, with a webbing stopper 132 rolled in therebetween. The webbing end provided with the webbing stopper 132 is engaged in the second slit 126.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spool for a seat belt retractor used for a vehicle such as an automobile, and more particularly to a spool for a seat belt retractor incorporating a torsion bar. Also, the present invention
The present invention relates to a seat belt retractor provided with the spool. Further, the present invention relates to a seat belt retractor having a mechanism for regulating an upper limit of the torsional rotation number of the torsion bar.

[0002]

2. Description of the Related Art A seat belt retractor in which a torsion bar is inserted into an inner hole of a spool, one end of the torsion bar is fixed to the spool, and the other end of the torsion bar can be engaged with a seat belt retractor frame by a clutch. It is known. In an emergency such as a vehicle collision, the other end of the torsion bar is locked to the frame by this clutch. Since one end of the torsion bar is fixed to the spool, when a force in the webbing unwinding direction is applied to the spool, the torsion bar is twisted, the spool is gradually rotated, and the webbing is gradually pulled out. Thereby, a part of the kinetic energy applied to the occupant's body is absorbed by the torsion bar torsion, and the impact is reduced.

A conventional example of a seat belt retractor having such a torsion bar (Japanese Utility Model Publication No. 61-11085)
) Will be described with reference to FIG. 5 to FIG.

In FIGS. 5 and 6, reference numeral 1 denotes a retractor body, which is fixed to a vehicle body by a bolt or the like in a hole 11 provided in the frame.

[0005] A pair of opposing side walls 12 and 13 are formed in the frame body 1, and a spool 2 is rotatably supported on these. The spool 2 has a cylindrical shape, and a torsion bar member 3 is disposed in an inner hole thereof.

The torsion bar member 3 has a rod-shaped torsion portion 3.
1 and a connecting portion 32 to the spool 2 formed at one end thereof
And a screw portion 33 formed at the other end and having a diameter larger than that of the torsion portion 31 and provided with a screw 331 on the outer periphery thereof, and a saw-toothed outer periphery of a flange-like circular plate 341 formed at a side end of the screw portion 33. And a gear portion 34 having a one-way operation gear 342. The twisting portion 31 is disposed coaxially with the bore of the spool 2, and a coupling portion 32 forming a square head is fitted into a square hole of the wall surface 21 formed at one end of the spool 2. I have. Therefore, the torsion bar member 3
The above-mentioned connecting portion 32 at one end rotates integrally with the spool 2. A ring 35 is fitted to the outer periphery of the screw portion 33 at a portion facing the inner peripheral surface of the spool 2.
It is slidable.

[0007] A flange 22 is formed at one end of the spool 2, and one surface thereof is formed on a side wall 1 of the retractor body 1.
A plurality of projections 23, 23,... Having a rectangular cross section project from the other surface of the gear portion 34 slidably in contact with the plate 341 at a predetermined interval.

The screw portion 33 of the torsion bar member 3 includes
An annular stopper member 4 provided with a screw on the inner periphery is screwed so as to be easily rotated. This stopper member 4
Are provided with holes 4 at positions opposed to the protrusions 23, 23,.
1, 41,... Are provided, and the projections 23, 2 are provided in these holes.
3, ... are loosely fitted.

One end of the webbing S is connected to the torsion portion 31 of the torsion bar member 3, and the webbing S is wound around the spool 2 and led out. The leading end is fixed to an anchor, buckle or the like (not shown). A case 14 is provided on a side surface of the side wall 12 of the retractor body 1 and a spring is mounted inside the spring 14. The spring is wound on the spool 2 in a webbing winding direction (arrow Y _{1 in} FIG. 6).
Direction). And webbing S
Unwound in response to the occupant of the body position (arrow Y ₂ direction Figure 6).

[0010] Brackets 15 are fixed to the lower ends of both side walls 12 and 13 of the retractor main body 1, and support the pendulum 5 in a movable state. A ratchet 6 is supported at the upper end of the pendulum 5, and the ratchet 6 is inclined and lifted by the vibration of the pendulum 5, and one end of the ratchet 6 meshes with the one-way operation gear 342 facing the torsion bar member 3. The rotation of one end of the torsion bar member 3 is locked.

[0011] In the above seat belt retractor,
Normally, the torsion bar member 3 is not locked by the ratchet 6, so that the torsion bar member 3 and the spool 2 are rotatable, and the webbing S is pulled out and wound in accordance with the occupant's position.

At the time of a vehicle collision, as shown in FIGS. 7 and 8, the pendulum 5 vibrates to lift the ratchet 6.
Thus the ratchet 6 have gear 342 meshing of the gear portion 34 of the torsion bar members 3, to prevent rotation of the webbing pull-out direction (FIG. 8 arrow Y ₂ direction).

On the other hand, a tensile force is applied to the webbing S due to the movement of the occupant at the time of a vehicle collision, and the spool 2 attempts to rotate in the webbing pull-out direction. At this time, when the rotational force of the spool 2 exceeds the stress limit of the torsion portion 31 of the torsion bar member 3 having one end connected to the spool 2, the spool 2 rotates while twisting the torsion portion 31. Thus, the impact energy of the occupant is absorbed.

When the spool 2 rotates, the stopper member 4 engaged with the projections 23 provided at one end thereof also rotates. In this case, the stopper member 4 is rotatably screwed with the screw portion 33 of the torsion bar member 3 and has a loose fit with the projection 23 of the spool 2, so that the stopper member 4 has a gear formed on the outer periphery. It moves in the direction of the plate 341. Then, when the spool 2 rotates and the torsion portion 31 of the torsion bar member 3 is twisted by a predetermined angle without breaking, the stopper member 4 comes into contact with the plate 341, whereby the rotation of the spool 2 is stopped. Therefore, even if an excessive occupant load is applied to the webbing S, the torsion bar member 3 does not break.

[0015]

As described above, it is not easy to firmly fix the end of the webbing to the spool in which the torsion bar is inserted into the inner hole. It should be noted that Japanese Utility Model Publication No. Sho 61-11095 does not describe how to fix the webbing S to the spool 2.

It is a first object of the present invention to enable a torsion bar to securely and easily fasten an end of a webbing to a spool inserted into an inner hole.

In the conventional example shown in FIGS. 5 to 8,
The stopper member 4 is disposed outside the flange 22 of the spool 2, and the seat belt retractor is moved to the frame side by the total length of the thickness of the stopper member 4 and the stroke of the stopper member 4 moving back and forth along the protrusion 23. Is sticking out.

The present invention eliminates such protrusions,
An object is to reduce the size of a seat belt retractor.

[0019]

A spool for a seat belt retractor according to the present invention is a spool for winding webbing of a seat belt retractor, the spool having a tubular portion having an inner hole through which a torsion bar is inserted. A plurality of webbing insertion slits extending in the chord direction in a cross section perpendicular to the cylinder axis are provided in the cylinder portion, and the end of the webbing can be passed through these slits and fastened to the spool. Is what you do.

According to a third aspect of the present invention, there is provided a seat belt retractor having a torsion bar inserted through a spool, wherein the spool is used as the spool.

In the spool of the seat belt retractor, the webbing end is passed through a plurality of slits, a stator is attached to the webbing end, for example, and the stator is locked at the entrance of the slit, thereby forming the webbing. Can be securely fastened to the spool. In this case, since the webbing is inserted through the plurality of slits, a large external force is not locally applied to the contact portion between the webbing and the spool.

According to a fourth aspect of the present invention, there is provided a seat belt retractor, wherein a cylindrical spool for winding the webbing, a frame supporting the spool, and an inner hole of the spool are connected to one end of the spool. And a locking means for locking the other end of the torsion bar when acceleration equal to or greater than a predetermined value is detected, and the locking means locks the other end of the torsion bar. In a seat belt retractor in which the torsion bar is torsionally deformed when a tensile force of a predetermined value or more is applied to the webbing in a state where the webbing is set, the locking means is locked to the frame when an acceleration of a predetermined value or more is detected. A pawl holder, a column protruding from the pawl holder and inserted into an inner hole of the spool, and a column provided on an outer periphery of the column. A male screw, an inner female screw is meshed with the male screw, and a stopper member that can advance and retreat in the spool axis direction along the column, and protrudes in a direction including the radial direction from the stopper member. A pair of projections provided on the spool, and a recess recessed from the inner hole of the spool and engaged with the projection, wherein the locking means operates and the webbing has a predetermined value or more. When the torsion bar is torsionally deformed by applying a tensile force, the stopper member is screwed toward the pawl holder, and the stopper member comes into contact with the pawl holder, whereby the torque of the spool is applied to the pawl holder via the stopper member. It is transmitted directly to prevent rotation of the spool.

In such a seat belt retractor, since the stopper member is disposed inside the inner hole of the spool, the protrusion outside the frame is smaller than that of the conventional example shown in FIGS. The retractor is downsized.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a spool according to an embodiment of the present invention, and FIG.
FIG. 2B is a cross-sectional view taken along line BB of FIG. 2 is a longitudinal sectional view of the seat belt retractor provided with the spool, FIG. 3 is a sectional view of the seat belt retractor in an operating state, and FIG. 4 is an exploded perspective view of the seat belt retractor.

This spool 50 has an inner hole 52 (FIG. 4).
The torsion bar 54 is inserted through the inner hole 52. One end of the torsion bar 54 is a first hexagonal portion 56. The first hexagonal portion 56 has a hexagonal portion 6 provided in an inner hole of the pawl holder 58.
0 is engaged. The pawl holder 58 includes a flange 62 and a column 64 projecting from the flange 62, and a hexagonal inner hole 60 is formed from the flange 62 to the column 64. A male screw 66 is engraved on the outer peripheral surface of the column 64.

A stopper member 70 having a female screw 68 engaged with the male screw 66 is screwed to the outer periphery of the column 64. The stopper member 70 has a pair of projections 70 a projecting in the diameter direction, and the projections 70 a are engaged with recesses 72 provided in the inner hole 52 of the spool 50.

A pawl 74 is pivotally attached to the flange 62 of the pawl holder 58. On the front side of the flange 62 of the pawl holder 58, a lock ring 76 coaxially arranged with the torsion bar 54 is arranged. A lock starter 78 and members such as springs 80 and 82 are mounted on the lock ring 76 so that the lock ring 76 can be used at the time of vehicle collision or when the spool 5
At the time of high-speed rotation of 0, the pawl 74 is projected from the outer periphery of the flange 62, and the pawl 74 is locked to the internal teeth of the internal toothed opening 86 of the frame 84. The frame 84 is 1
It comprises a pair of frame sides 84a, 84b, between which the spool 50 is arranged.

The lock ring 76 is covered by a cover 88. A lock activation mechanism 90 for locking the lock ring 76 is held by the frame 84, and is similarly covered by a cover 88.

This lock actuating mechanism 90 is held by a holder 92 and is capable of tilting, and a lever 96 pivotally supported by the holder 92 and superposed on the weight 94.
It has. When acceleration exceeding a predetermined level occurs in the vehicle, the weight 94 tilts, the lever 96 is flipped up, and the lever 9
The distal end of the lock ring 6 engages with external teeth on the outer periphery of the lock ring 76, and the lock ring 76 stops rotating. As a result, the pawl 74 projects from the outer periphery of the flange 62, and the pawl holder 58 engages with the opening 86 with the internal teeth of the frame 84. The configuration of such a lock mechanism 100 is well known.

A second hexagonal portion 102 is provided at an end of the torsion bar 54 opposite to one end where the hexagonal portion 56 is disposed. This second hexagonal portion 102 is
And a hexagonal portion 104 (FIGS. 2 and 3) provided in the inner hole 52 of FIG.

The spool 50 on which the torsion bar 54 and the like are mounted is mounted on the frame side 84 of the frame 84.
a, 84b. A reverse screw 105 is provided on the tip side of the torsion bar 54 further than the hexagonal portion 102, and a splined nut 106 is screwed to the reverse screw 105. The nut 106 is inserted into the inner hole 112 of the pretensioner 110.

The pretensioner 110 is for removing the slack of the webbing by winding the spool 50 in the webbing winding direction with a large torque a predetermined number of times at the time of a vehicle collision. The pretensioner 110 includes a gas generator 114 that generates gas at the time of a vehicle collision, a torque generator 116 that generates torque by the gas generated by the gas generator 114, and a nut that generates torque by the torque generator 116. And a torque transmission unit 118 for transmitting the torque to the transmission 106. Note that the torque transmitting means 118
Is configured to transmit only the torque from the torque generating means 116 to the nut 106 and not transmit the torque transmitted from the nut 106 to the torque generating means 116.

The tip of the torsion bar 54 passes through the pretensioner 110 and
Are engaged with the inner hole 122. The spring unit 120 is connected to the spool 5 via the torsion bar 54.
0 is always urged in the webbing winding direction.

As clearly shown in FIG. 1B, the spool 50 has a first slit 124 and a second slit extending in a chord direction in a cross section perpendicular to the axis of the spool 50. 126 are provided. Webbing 1
The end of 30 is sequentially inserted into these slits 124 and 126. The end of the webbing 130 is folded back and overlapped, and the overlapped portion is sewn. A webbing stopper 132 is provided so as to be wound around a portion formed into a loop by sewing. When the webbing stopper 132 engages with the entrance of the second slit 126, the webbing 13
There is no omission.

As shown in FIG. 1 (b), the first slit 124 and the second slit 126 extend in a direction parallel to each other.

Next, the operation of the seat belt retractor will be described. When the vehicle is in a steady state, the stopper member 70 is connected to the pawl holder 58 as shown in FIG.
From the flange 62. In this case, the lock mechanism 100 and the pretensioner 110 are not operating,
The spool 50 is urged by the mainspring unit 120 in the winding direction. When the webbing 130 is pulled out, the spool 50 is attached to the spring unit 12.
Rotating in the webbing pull-out direction while being urged in the winding direction by 0.

When a vehicle collides, the pretensioner 11
0 operates, and a strong torque is applied to the torsion bar 54 in the webbing winding direction. This torque rotates the spool 50 through the hexagonal portion 102 of the torsion bar 54 and the hexagonal portion 104 of the spool 50, and winds the webbing 130 by a predetermined length.

In the event of a vehicle collision, the weight 94 of the lock mechanism 90 tilts, the lock ring 76 is locked by the lever 96 of the lock activation mechanism 90, and the pawl 74 projects from the outer periphery of the flange 62 and has internal teeth. The pawl holder 58 is engaged with the opening 86 and is prevented from rotating in the webbing withdrawing direction.

At the time of a vehicle collision, the occupant of the vehicle moves so that the occupant is thrown forward, and a strong pulling-out direction force is applied to the webbing 130. As described above, the hexagonal portion 104 of the spool 50 and the hexagonal portion 10 of the torsion bar 54
2 and the pawl holder 58 cannot rotate in the webbing withdrawal direction, the torsion bar 5
4 is twisted between two hexagons 56,102. Then, the spool 50 rotates in the webbing pull-out direction while twisting the torsion bar 54, and the impact applied to the occupant due to the torsion of the torsion bar 54 is absorbed.

In the state where the pawl holder 58 is locked to the frame 84 so as not to rotate, the spool 5
When 0 rotates in the webbing withdrawing direction, the stopper member 70 integrated with the spool 50 by the engagement of the concave portion 72 and the projection 70 a rotates integrally with the spool 50. Since the female screw 68 of the stopper member 70 meshes with the male screw 66 of the pawl holder 58, when the stopper member 70 rotates with the rotation of the spool 50 in the webbing withdrawing direction, the stopper member 70 Then, the stopper member 70 comes into contact with the rear surface of the flange 62 (FIG. 3).

As a result, further rotation of the stopper member 70 is prevented, and rotation of the spool 50 is also prevented.
That is, the rotation of the spool 50 is allowed only while the stopper member 70 moves from the state of FIG. 2 to the state of FIG. 3, and further rotation in the webbing withdrawing direction is prevented. In this way, the maximum torsional rotation speed of the torsion bar 54 is defined, and the torsion bar 54 is prevented from being torn.

In this embodiment, since the stopper member 70 is disposed inside the inner hole 52 of the spool 50, the fifth to fifth stoppers are disposed outside the frame.
As compared with the conventional example shown in FIG. 8, the protrusion to the outside of the frame 84 (to the right in FIGS. 2 and 3) is small, and the seat belt retractor is smaller than the conventional example.

When the stopper member 70 is in contact with the flange 62 as shown in FIG. 3, the torque applied to the spool 50 in the pull-out direction of the webbing 130 is applied to the pawl holder 58 via the spool 50 and the column 64. Is transmitted to Since the pair of projections 70a projecting in the diameter direction from the stopper member 70 and the concave portion 72 of the spool 50 are engaged with each other, the connecting portion between the spool 50 and the stopper member 70 is very firm, and is sufficiently large torque. Can withstand. Further, even if the stopper member 70 is located between the pawl holder 58 and the stopper member 70,
Torque is transmitted when the female screw 68 is engaged with the male screw 66 of the column 64 integrated with the pawl holder 58 and the stopper member 70 is pressed directly against the pawl holder 58, so that the torque is transmitted between the spool 50 and the stopper member 70. A sufficiently large torque can be transmitted. Therefore, even when a significantly large pulling force is applied to the webbing 130, the spool 50 is securely locked to the frame side 84a.

FIG. 9 is a sectional view of a seat belt retractor according to another embodiment, and is a sectional view corresponding to FIG. 2 of the above embodiment. In this embodiment, the inner hole 52 of the spool 50 is a hole having the same diameter except for the hexagonal portion 104 on the left end side in the drawing. In other words, in the embodiment shown in FIGS. 1 to 4, as shown in FIGS. 2 and 3, the right end portion of the inner hole 52 surrounding the column 64 has a larger diameter than the left portion. A step is present at the boundary between the large-diameter portion on the right end side and the small-diameter portion on the left end side, and the stopper member 70 can come into contact with the step portion as shown in FIG.

On the other hand, in FIG. 9, the portion of the inner hole 52 other than the hexagonal portion 104 is a hole having the same diameter, so that such a step does not exist.

Other configurations of the seat belt retractor shown in FIG. 9 are the same as those of the seat belt retractor shown in FIGS. 1 to 4, and the same reference numerals denote the same parts.

FIG. 10 is a sectional view of a seat belt retractor according to still another embodiment of the present invention, and shows a state corresponding to FIG.

Also in this embodiment, the inner hole 52 is a hole having the same diameter except for the hexagonal portion 104.

In this embodiment, the cylindrical portion 58A is connected to the column 64 from the tip of the column 64 of the pawl holder 58.
The bush 150 is externally fitted to the cylindrical portion 58A. This bush 150 has an inner hole 5
2 is slidably in contact with the inner peripheral surface. The provision of the bush 150 ensures that the torsion bar 54, the pawl holder 58, and the spool 50 have a coaxial positional relationship. Other configurations of the seat belt retractor of FIG. 10 are the same as those of the seat belt retractors of FIGS. 1 to 4, and the same reference numerals indicate the same parts.

The operation of the seat belt retractor of FIGS. 9 and 10 is the same as that of the seat belt retractor of FIGS. That is, when the vehicle is in a steady state, the stopper member 70 is separated from the flange 62 of the pawl holder 58 and is located on the left end side of the male screw 66 of the column 64 as shown in FIGS. In this case, the lock mechanism 100 and the pretensioner 110 are not operating,
The spool 50 is urged by the mainspring unit 120 in the winding direction. When the webbing 130 is pulled out, the spool 50 is attached to the spring unit 12.
Rotating in the webbing pull-out direction while being urged in the winding direction by 0.

When the vehicle collides, the pretensioner 11
0 operates, and a strong torque is applied to the torsion bar 54 in the webbing winding direction. This torque rotates the spool 50 through the hexagonal portion 102 of the torsion bar 54 and the hexagonal portion 104 of the spool 50, and winds the webbing 130 by a predetermined length.

In the event of a vehicle collision, the weight 94 of the lock mechanism 90 tilts, the lock ring 76 is locked by the lever 96 of the lock activation mechanism 90, and the pawl 74 projects from the outer periphery of the flange 62 and has internal teeth. The pawl holder 58 is engaged with the opening 86 and is prevented from rotating in the webbing withdrawing direction.

At the time of a vehicle collision, the body of the vehicle moves so that the occupant is thrown forward, and a strong pulling-out direction force is applied to the webbing 130. As described above, the hexagonal portion 104 of the spool 50 and the hexagonal portion 10 of the torsion bar 54
2 and the pawl holder 58 cannot rotate in the webbing withdrawal direction, the torsion bar 5
4 is twisted between two hexagons 56,102. Then, the spool 50 rotates in the webbing pull-out direction while twisting the torsion bar 54, and the impact applied to the occupant due to the torsion of the torsion bar 54 is absorbed.

When the pawl holder 58 is locked to the frame 84 so as not to rotate, the spool 5
When 0 rotates in the webbing withdrawing direction, the stopper member 70 integrated with the spool 50 by the engagement of the concave portion 72 and the projection 70 a rotates integrally with the spool 50. Since the female screw 68 of the stopper member 70 meshes with the male screw 66 of the pawl holder 58, when the stopper member 70 rotates with the rotation of the spool 50 in the webbing withdrawing direction, the stopper member 70 Then, the stopper member 70 comes into contact with the back surface of the flange 62 (similar to FIG. 3).

As a result, further rotation of the stopper member 70 is prevented, and rotation of the spool 50 is also prevented.
That is, the rotation of the spool 50 is allowed only while the stopper member 70 contacts the flange 62 from the state of FIG. 9 or FIG. 10, and further rotation in the webbing withdrawing direction is prevented. In this way, the maximum torsional rotation speed of the torsion bar 54 is defined, and the torsion bar 54 is prevented from being torn.

In the seat belt retractors shown in FIGS.
, The protrusion of the frame 84 to the side and outside is small, and the seat belt retractor is reduced in size.

In the seat belt retractor of the present invention, as shown in FIG. 11, a resin or rubber ring 160 is interposed between the outer periphery on the tip side of the column 64 and the inner hole 52 of the spool. You may comprise so that generation of abnormal noise may be prevented. Other configurations in FIG. 11 are the same as those in FIG. 2, and the same reference numerals indicate the same parts.

In the above embodiment, the spool 50
Are provided with two slits 124 and 126,
Three or more slits may be provided. However, in the case of a seat belt retractor of a normal size, it is preferable to provide two slits 124 and 126 as shown in FIG.
In this case, it is preferable to provide the slits 124 and 126 in parallel in order to equalize the stress applied to the spool 50.

Although the pretensioner 110 is used in the above embodiment, the present invention can also be applied to a seat belt retractor having no pretensioner. Further, the spool of the present invention can be applied also as a spool of the conventional seat belt retractor shown in FIGS.

[0060]

As described above, according to the present invention, the webbing can be extremely firmly fastened to the spool, and the fastening operation is easy.

According to the present invention, the seat belt retractor can be downsized by disposing the stopper member inside the inner hole of the spool.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a spool according to an embodiment.

FIG. 2 is a longitudinal sectional view of a seat belt retractor provided with a spool according to the embodiment.

FIG. 3 is a cross-sectional view illustrating an operation state of the seat belt retractor of FIG. 2;

FIG. 4 is an exploded perspective view of the seat belt retractor according to the embodiment.

FIG. 5 is a longitudinal sectional view of a conventional seat belt retractor.

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5;

FIG. 7 is a longitudinal sectional view showing an operation state of the seat belt retractor of FIG. 5;

8 is a sectional view taken along the line VIII-VIII in FIG.

FIG. 9 is a longitudinal sectional view of a seat belt retractor according to another embodiment.

FIG. 10 is a longitudinal sectional view of a seat belt retractor according to still another embodiment.

FIG. 11 is a longitudinal sectional view of a seat belt retractor according to another embodiment.

[Explanation of symbols]

 2, 50 spool 52 inner hole 54 torsion bar 58 pawl holder 74 pawl 84 frame 86 opening with internal teeth 90 lock activation mechanism 100 locking mechanism 110 pretensioner 120 mainspring unit 124 first slit 126 second slit 130 webbing 150 bush 160 ring

Claims (5)

[Claims] 1. A spool for winding a webbing of a seat belt retractor, said spool having a tubular portion having an inner hole through which a torsion bar is inserted, wherein said tubular portion has a chord in a cross section perpendicular to the tubular axis. A plurality of webbing insertion slits extending in the direction, and the end of the webbing can be passed through these slits and fastened to the spool. 2. The spool for a seat belt retractor according to claim 1, wherein two slits are provided, and these slits extend in a parallel direction in the cross section. 3. A seat belt retractor in which a shock applied to an occupant is absorbed by a torsion bar connected to a spool, wherein the spool is the one according to claim 1 or 2. Retractor. 4. A cylindrical spool for winding the webbing, a frame for supporting the spool, a torsion bar inserted through an inner hole of the spool and having one end connected to the spool, and an acceleration not less than a predetermined value. And a locking means for locking the other end of the torsion bar when the torsion bar is detected. When the locking means locks the other end of the torsion bar, the webbing has a tensile force of a predetermined value or more. When the torsion bar is torsionally deformed, the locking means includes: a pawl holder that is locked to the frame when an acceleration equal to or greater than a predetermined value is detected; A column inserted into the inner hole of the spool, a male screw provided on the outer periphery of the column, and a female screw on the inner circumference with respect to the male screw Combined and, projecting in a direction that includes a stopper member that can advance and retreat in the spool axial line direction along the column, a radial direction from the stopper member 1
A pair or more protrusions, and a recess recessed from the inner hole of the spool and engaging the protrusions, wherein the locking means is activated and the webbing has a tensile force of a predetermined value or more. In addition, when the torsion bar is torsionally deformed, the stopper member is screwed toward the pawl holder, and the stopper member comes into contact with the pawl holder, whereby torque of the spool is directly transmitted to the pawl holder via the stopper member. A seat belt retractor, wherein rotation of a spool is prevented. 5. The seat belt retractor according to claim 4, wherein the spool is the spool according to claim 1 or 2.