JP2000052922A - Webbing take-up device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a webbing take-up device without hurting even if the wind up torque difference between a large spring and a small spring is set to large. SOLUTION: A coil shape brake spring 50 is arranged while winding around the big diameter 32 in the gap between the disc 40 of a spring seat 36 and the big diameter 32 of an adaptor 24. When the spring seat 36 is rotated in the webbing wind up direction by the elastic force of a large spring 64, the brake spring 50 is wound to the big diameter part 32 of the adaptor 24 and makes the resistance of rotation. Therefore, as the small spring 34 is rotated with a small rotational angular velocity and makes an entire stick state, the hurt is not generated even if the elastic force difference (wind up torque difference) between the large spring 64 and the small spring 34 is set to large.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a webbing winding device.

[0002]

2. Description of the Related Art FIGS. 13 to 15 partially show a conventional webbing winding device 102. FIG.

In this webbing take-up device 102, a spiral small spring 11 is attached to an adapter 108 which rotates integrally with a spool 106 for taking up the webbing 104.
0 is fixed at the inner end. Small spring 110
The inner end of a spiral large spring 114 having a greater elasticity than the small spring 110 is fixed to the spring seat 112 to which the outer end of the spring is fixed. Small spring 110 and large spring 114
Urge the spool 106 to rotate in the webbing winding direction.

Further, ratchet teeth 116 are formed on the outer periphery of the spring seat 112 so that the webbing 11 is formed.
When the tongue plate provided at 4 is inserted into a buckle (both not shown) and locked, the solenoid 11
8, the pawl 120 is engaged with the ratchet teeth 116, and the rotation of the spring seat 112 in the webbing winding direction (the direction of arrow A) is prevented.

[0005] The webbing take-up device 10 having such a configuration.
2, when the webbing 104 is pulled out, the webbing pulling force acts on the small spring 110 so that the small spring 110 is wound inward by a predetermined length, and this pulling force is transmitted to the large spring 114 via the spring seat 112. The large spring 114 is also tightened by a predetermined length. here,
When the tongue plate is inserted into the buckle and locked,
Since the pawl 120 is engaged with the ratchet teeth 116 and the rotation of the spring seat 112 in the webbing winding direction is prevented, the elastic force of the large spring 114 does not act on the spool, and only the small elastic force of the small spring 110 is applied. Acting on the spool, the feeling of pressure on the webbing wearer is reduced.

However, if the tongue plate is removed from the buckle in this state, the pawl 120 is separated from the ratchet teeth 116 and the spring seat 112 is rotatable in the webbing winding direction. Due to the large elastic force of the large spring 114, the spring seat 112 rapidly rotates in the webbing winding direction. Then, due to this elastic force, as shown in FIG. 15, the small spring 110 is brought into a state of full contact in a short time.

As described above, the elastic energy of the large spring 114 is released at a stretch in a short time, and the small spring 110 is brought into full contact with the impact, so that the small spring 110 itself and the small spring 110
A large impact force acts on a portion fixed to the spring seat 112 and the adapter 108 (particularly, a portion fixed to the adapter 108). Therefore, the small spring 110 itself, or the small spring 110 and the spring seat 1
In order to prevent breakage of the fixed portion between the large spring 12 and the adapter 108, the difference between the elastic force of the large spring 114 and the elastic force of the small spring 110 (difference in winding torque) must be set small.

[0008]

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a webbing take-up device which will not be damaged even if the difference in the take-up torque between the large spring and the small spring is set large. .

[0009]

According to the first aspect of the present invention, there is provided a spool capable of winding a webbing, and an inner end fixed to the spool to rotationally urge the spool in a webbing winding direction by elastic recovery. 1 spiral spring, a rotating body having an outer end fixed to the first spiral spring and rotatable coaxially with the spool, and a webbing winding direction larger than the first spiral spring having an inner end fixed to the rotating body. A second spiral spring for transmitting elastic force to the spool via the rotating body and the first spiral spring, and engaging with the rotating body when it is detected that the webbing is mounted on the occupant. A pawl that prevents rotation in the take-off direction, and the pawl that rotates together with the rotating body, the pawl releases engagement with the rotating body, and the rotating body is relatively webbed with respect to the spool by the elastic force of the second spiral spring. Winding method And having a brake spring for applying a frictional resistance to rotation of the rotating body wrapped around the spool rotates in.

When the pawl is not engaged with the rotating body, the rotating body is not prevented from rotating in the webbing pull-out direction. Then, the webbing can be pulled out and taken up by rotating the spool in the direction of the elastic force (rotary urging force) of the first spiral spring and in the opposite direction.

When the webbing is pulled out and the spool is rotated in a direction opposite to the elastic force of the first spiral spring, the first spiral spring is wound inward, and a certain elastic energy is accumulated in the first spiral spring. Also, the second through the rotating body
The spiral spring is also wound inward by a predetermined amount, and a certain elastic energy is stored. At this time, when it is detected that the webbing is mounted on the occupant by inserting the tongue plate into the buckle and engaging the buckle, the pawl is engaged with the rotating body, and the rotation of the rotating body in the webbing winding direction is stopped. Block. Accordingly, only the elastic force of the first spiral spring acts on the spool, and the feeling of pressure on the webbing wearer is reduced.

Here, when the engagement of the pawl with the rotating body is released, the large elastic force of the second spiral spring acts on the rotating body, so that the rotating body rotates at a large angular velocity. However, when the rotating body relatively rotates with respect to the webbing take-up traveling with respect to the enabler plate, a brake spring that rotates together with the rotating body winds around the spool and exerts frictional resistance on the rotation of the rotating body. For this reason, the rotation angular velocity of the rotating body decreases, and the elastic force (rotation driving force) of the second spiral spring acting on the first spiral spring via the rotating body also decreases.
Thereby, the rotation speed when the first spiral spring is in a so-called full contact state is reduced.

As described above, a part of the elastic force of the second spiral spring is absorbed as the frictional force between the brake spring and the spool and the rotation speed of the first spiral spring is reduced, so that the elastic force of the second spiral spring is reduced. And even if the difference between the elastic force of the first spiral spring and the elastic force of the first spiral spring is set to be large, the first spiral spring does not come into full contact with the impact, and a part of the webbing retractor does not break.

According to a second aspect of the present invention, in the first aspect of the present invention, the spool is disposed between the rotating body and the brake spring in a direction opposite to an elastic force direction of the second spiral spring. Is characterized by having a rotor for preventing the brake spring from winding around the spool when the relative rotation amount is less than a predetermined amount.

That is, even if the spool is relatively rotated with respect to the rotating body in the direction opposite to the elastic force direction of the second spiral spring, if the amount of rotation is equal to or less than a predetermined amount, the spool of the brake spring is rotated. Winding around is prevented by the rotor. For this reason, unnecessary resistance force for rotation does not act on the spool, and the spool can be smoothly rotated with a small force.

[0016]

1 and 3 show a first embodiment of the present invention.
The webbing take-up device 12 according to the embodiment is partially shown. 2 and 4 show a part of the webbing take-up device 12 in an enlarged manner.

As shown in FIG. 1, the webbing take-up device 12 has a cylindrical take-up cylinder 16 for taking up the webbing 14. The take-up cylinder 16 is attached to a frame 15 (see FIG. 4, not shown in FIGS. 1 to 3) so as to be rotatable around the axis J, and the webbing 14 is rotated by rotation of the take-up cylinder 16. It is wound up and pulled out.

A casing 18 is fixed to the frame 15. A flange 20 is provided around the casing 18.
And the inside of the flange 20 is a storage portion.

As shown in FIG. 4, the casing 18 has a cylindrical flange 20 inside (in the center of the accommodation portion).
An insertion hole 22 is formed. A substantially cylindrical adapter 24 is rotatably inserted into the insertion hole 22. An enlarged diameter portion 26 swelling radially outward is formed substantially at the center of the adapter 24 in the longitudinal direction, and the enlarged diameter portion 26 hits the casing 18 to position the adapter 24 in the longitudinal direction.

At one end of the adapter 24, a shaft 28 protruding from the winding cylinder 16 is inserted and fixed (in FIG. 4, the shaft 28 is not shown). This allows
The take-up cylinder 16 and the adapter 24 rotate integrally. The spool 29 of the present invention is constituted by the take-up cylinder 16, the adapter 24 and the shaft 28.

The other end of the adapter 24 is reduced in diameter in the radial direction, and has a small diameter portion 30 and a large diameter portion 32 from the other end. The inner end of a spiral small spring 34 is fixed to the large diameter portion 32. As also shown in FIGS. 2 and 3,
The outer end of the small spring 34 is the spring seat 3
6 is fixed to the fixing portion 38 formed in the fixing member 6. The small spring 34 is wound in a predetermined direction so as to urge the spool 29 to rotate in the webbing winding direction (direction of arrow A) via the adapter 24 by elastic force.

The spring seat 36 has a disk portion 40 coaxial with the axis J, a substantially flat cylindrical large-diameter cylindrical portion 42 extending from the vicinity of the outer periphery of the disk portion 40 toward the adapter 24, and And a small-diameter cylindrical portion 43 extending from the radially inner side of the disk portion 40 to the opposite side from the large-diameter cylindrical portion 42. As shown in FIG. 4, the small spring 34 is housed inside the large-diameter cylindrical portion 42. In addition, the large-diameter cylindrical portion 4
2 is formed on the inner surface side of FIG.
reference).

The small diameter portion 30 of the adapter 24 is inserted inside the small diameter cylindrical portion 43 of the spring seat 36.
A housing recess 44 is formed inside the disk portion 40 of the spring seat 36, and the coil is wound around the large diameter portion 32 in the gap between the housing recess 44 and the large diameter portion 32 of the adapter 24. A brake spring 50 is disposed. One end of the brake spring 50 is extended outward in the radial direction to form an engaging portion 52. Engaging part 52
Are inserted into engagement grooves 54 (see FIGS. 2 to 4) formed in the spring seat 36, and the outer end side of the brake spring 50 and the spring seat 36 rotate integrally.

The spring seat 36 is connected to the adapter 2.
Webbing winding direction relative to 4 (arrow A direction)
When the outer end side of the brake spring 50 also rotates in the webbing winding direction, the brake spring 50 is wound in a predetermined direction so as to wind around the large-diameter portion 32 as shown in FIG. . As a result, when the spring seat 36 tries to rotate in the webbing winding direction (the direction of the arrow A), a frictional force acts, and the rotation of the spring seat 36 becomes a resistance.

Ratchet teeth 56 are formed on the outer periphery of the large diameter cylindrical portion 42 of the spring seat 36. on the other hand,
A pawl 60, which is rotated by a solenoid 58 and can engage with the ratchet teeth 56, is supported on a cover 66 described later. The pawl 60 is urged by a spring 62 in a direction away from the ratchet teeth 56. When the pawl 60 is engaged, the ratchet teeth 56 prevent rotation of the spring seat 36 in the webbing take-up direction (arrow A direction), but do not prevent rotation of the spring seat 36 in the webbing pull-out direction (arrow B direction). And is formed to be inclined in a predetermined direction.

The solenoid 58 is connected to the webbing take-up device 1
2 is electrically connected to the buckle (not shown),
When a tank plate (not shown) is inserted into the buckle, the solenoid 58 is energized. Therefore, when the tongue plate is inserted into the buckle, the solenoid is energized, and the pawl 60 rotates against the urging force of the spring 62 and engages with the ratchet teeth 56, so that the webbing winding direction of the spring seat 36 ( (Arrow A direction)
Is prevented from rotating. When the tongue plate is pulled out of the buckle, the solenoid 58 is de-energized, and the pawl 60 is rotated by the biasing force of the spring 62 to be separated from the ratchet teeth 56. In either direction.

The inner end of a spiral large spring 64 is fixed to the flat cylindrical small-diameter cylindrical portion 43 erected from the spring seat 36. Large spring 64
Is formed to be wider with a higher rigidity metal so as to have a higher elastic constant than the small spring 34.

The outer end of the large spring 64 is
6 is fixed to a fixing portion 68 formed in the fixing member 6. The winding direction of the large spring 64 is determined by the spring seat 3
6 is a direction for urging the webbing 6 to rotate in the webbing winding direction.

The cover 66 is provided with a predetermined mounting portion, and the mounting portion allows the cover 66 to be mounted on the casing 1.
8 attached. In the mounted state, the small spring 34, the brake spring 50, the spring seat 36, the large spring 64, the pawl 60, the spring 62, and the solenoid 58 are accommodated between the casing 18 and the cover 66, and are covered by the cover 66.

Next, the operation of the webbing take-up device 12 according to the first embodiment will be described.

When the webbing 14 (see FIG. 1) is not mounted on the occupant, the tongue plate is not inserted into the buckle, and as shown in FIG.
8 is not energized and pawl 60 has ratchet teeth 56
The spring seat 36 is rotatable in both the webbing winding direction (arrow A direction) and the webbing pull-out direction (arrow B direction).

When the webbing 14 is pulled out, the spool 29 (see FIG. 1) rotates in the webbing pulling-out direction due to the pulling-out force. By this rotation, as shown in FIG. 5, the inner end of the small spring 34 rotates in the webbing pull-out direction, and the small spring 34 is wound inward. Further, since the outer end of the small spring 34 also rotates in the webbing pull-out direction, a part of the webbing pull-out force acts on the inner end of the large spring 64 via the spring seat 36. Therefore, the large spring 64 is also wound inside. As a result, the spool 29 is urged in the webbing winding direction (the direction of the arrow A) by the elastic force of the small spring 34 and the large spring 64.
The webbing 14 is wound around the winding cylinder 16 with a predetermined winding force.

When the webbing 14 pulled out by a predetermined length is mounted on the occupant, and the tongue plate is inserted into the buckle, as shown in FIG. And 56 are engaged. Since the rotation of the spring seat 36 in the webbing winding direction (the direction of the arrow A) is prevented, the large spring 64 is maintained in a state of being tightened by a predetermined length. Since the urging force of the large spring 64 does not act on the spool 29 via the spring seat 36 and the small spring 34, the small spring 3
Only the urging force of 4 acts. For this reason, the load from the webbing to the webbing wearer is reduced, and the feeling of pressure on the webbing wearer is reduced.

When the occupant pulls out the webbing 14 in this state, the small spring 34 is further tightened inward. FIG. 6 shows the small spring 34 further wound inward.

When the tongue plate is extracted from the buckle, the solenoid 58 is de-energized, and the pawl 60 is rotated by the urging force of the spring 62 to separate from the ratchet teeth 56 as shown in FIG. This allows the spring seat 36 to rotate in the webbing winding direction (the direction of arrow A). Since the large spring 64 is wound inside by a predetermined amount and a large amount of elastic energy is accumulated,
Due to this elastic energy, the spring seat 36 starts rotating at a large angular velocity in the webbing winding direction.

On the other hand, since the adapter 24 does not rotate or rotates at a lower angular velocity than the spring seat 36, the spring seat 36 is relatively moved with respect to the spool 29 in the webbing winding direction (the direction of arrow A). Rotate. By this relative rotation, the brake spring 5
0 is wound around the large diameter portion 32, and resistance is generated in the rotation of the spring seat 36, and the angular velocity of the rotation is reduced. further,
Small spring 34 via spring seat 36
The urging force (rotational driving force) of the large spring 64 acting on the inner end of the large spring 64 also decreases. For this reason, the inner end of the small spring 34 rotates at a smaller rotation angular velocity as compared with the conventional case in which the brake spring 50 is not provided, and the impact when the small spring 34 is in the so-called fully adhered state is small. Become.

As shown in FIG. 8, the large spring 64
Is in a natural state, the rotation of the spring seat 36 in the webbing winding direction is stopped, so that the brake spring 50 is loosened and separated from the large-diameter portion 32 of the adapter 24. Then, the small spring 34 elastically returns to the natural state.

As described above, in the webbing take-up device 12 according to the first embodiment, the pawl 60 is
6 and the spring seat 36 rotates in the webbing winding direction relatively to the inertia plate 44, a part of the elastic force (rotational driving force) of the large spring 64 is transmitted to the large-diameter portion 32 of the adapter 24. Absorbed as frictional force with the brake spring 50, the spring seat 3
The angular velocity of the rotation of No. 4 decreases. For this reason, even if the difference between the elastic force of the large spring 64 and the elastic force of the small spring 34 is set to be large, the rotational angular velocity when the small spring 34 is in the fully adhered state is limited, and the small spring 34 is impacted. Not fully adhered. Accordingly, the small spring 34 and the fixed portions of the small spring 34, the adapter 24, and the spring seat 36 are not damaged by the impact when the state of full contact is reached.

Further, as compared with the conventional webbing retractor, only the brake spring 50 is provided, so that the structure does not become complicated.

FIGS. 9 and 11 partially show a webbing take-up device 72 according to a second embodiment of the present invention. 10 and 12 show a part of the webbing take-up device 72 in an enlarged manner. Hereinafter, the same components, components, and the like as those of the webbing take-up device 12 according to the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

The webbing retractor 72 according to the second embodiment is different from the webbing retractor 12 according to the first embodiment in that the housing recess 4
4 is extended to the inner peripheral surface of the large-diameter cylindrical portion 42 to form a large-diameter cylinder.
And the point that a rotor 74 is provided.

The rotor 74 is formed in an annular shape, and has an engagement groove 76 formed on the inner periphery thereof to which the engagement portion 52 is engaged, and a projection 78 protruding from the outer periphery. Further, a projection 80 is also provided from the inner peripheral surface of the large-diameter cylindrical portion 42.

As shown in FIG. 11, in a normal state, the protrusion 78 of the rotor 74 is in contact with the protrusion 80 of the large-diameter cylindrical portion 42 in the webbing pull-out direction (direction of arrow B). . For this reason, the relative rotation of the rotor 74 in the webbing withdrawing direction with respect to the spring seat 36 is allowed, but when the rotor 74 rotates about one rotation (360 °), the protrusion 8
0 contacts the protruding portion 78 in the webbing winding direction (the direction of arrow A), and the spring seat 36 rotates integrally with the rotor 74. The elastic force (resistive force) from the large spring 64 acts on this rotation. It has become.

In the webbing take-up device 72, the webbing 14 (see FIG. 1) is pulled out and mounted on an occupant.
The operation until the pawl 60 engages with the ratchet teeth 56 to limit the rotation of the spring seat 36 in the webbing winding direction is the same as that of the webbing winding device 12 according to the first embodiment (FIG. 3). 5 and 6).

Next, the wearer of the webbing 14
When the spool 29 is rotated in the webbing withdrawing direction (the direction of arrow B), the spring seat 33 is relatively moved.
Also rotates in the webbing winding direction (the direction of arrow A). However, when this rotation amount is less than about one rotation, the rotation of the rotor 74 prevents the tightening of the brake spring 50, and the brake spring 50
Is maintained in a non-contact position. For this reason, the brake spring 50 does not wind around the adapter 24 and the spool 29
Friction does not act on the rotation of. For webbing wearers,
The webbing can be smoothly pulled out with a small force without feeling unnecessary resistance.

The operation after extracting the tongue plate from the buckle is the same as that of the webbing winding device 12 according to the first embodiment (see FIGS. 7 and 8).

In the above description, when the spring seat 36 rotates relative to the inertia plate 44 in the webbing winding direction, the inertia plate 4
Although the brake spring 50 is used in order to integrate the 4 with the spring seat 36, the friction member is not limited to this.

[0048]

According to the first aspect of the present invention, there is provided a spool capable of winding the webbing, and a first spiral spring having an inner end fixed to the spool and elastically restoring the spool to rotate in the webbing winding direction. A rotating body having an outer end fixed to the spool and rotatable coaxially with the spool; and an inner end fixed to the rotating body and having a greater elastic force in a webbing winding direction than the first spiral spring. A second spiral spring transmitting the rotation to the spool via a rotating body and a first spiral spring;
When it is detected that the webbing is attached to the occupant, a pawl that engages with the rotating body to prevent rotation in the webbing winding direction, rotates with the rotating body, and the pawl engages with the rotating body. And when the rotating body is rotated in the webbing winding direction relative to the spool by the elastic force of the second spiral spring, the brake spring is wound around the spool to exert frictional resistance on the rotation of the rotating body. Therefore, even if the difference between the elastic force of the second spiral spring and the elastic force of the first spiral spring is set to be large, the first spiral spring does not come into full contact with the impact, and a part of the webbing retractor. Will not be damaged.

According to a second aspect of the present invention, in the first aspect of the present invention, the spool is disposed between the rotating body and the brake spring in a direction opposite to an elastic force direction of the second spiral spring. When the relative rotation amount is less than a predetermined amount, the rotor has a rotor that prevents the brake spring from winding around the spool, so that unnecessary resistance is not applied to the rotation of the spool and the spool can be rotated smoothly with a small force. Can be.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view showing an enlarged part of the webbing take-up device according to the first embodiment of the present invention.

FIG. 3 is a partially cutaway front view of the webbing take-up device according to the first embodiment of the present invention.

FIG. 4 is a longitudinal sectional view partially showing the webbing take-up device according to the first embodiment of the present invention.

FIG. 5 is a front view showing an operation state of the webbing take-up device according to the first embodiment of the present invention, partially cut away;

FIG. 6 is a partially cutaway front view showing an operation state of the webbing take-up device according to the first embodiment of the present invention.

FIG. 7 is a partially cutaway front view showing an operation state of the webbing take-up device according to the first embodiment of the present invention.

FIG. 8 is a partially cutaway front view showing an operation state of the webbing take-up device according to the first embodiment of the present invention.

FIG. 9 is an exploded perspective view partially showing a webbing take-up device according to a second embodiment of the present invention.

FIG. 10 is an exploded perspective view showing an enlarged part of a webbing take-up device according to a second embodiment of the present invention.

FIG. 11 is a partially cutaway front view showing a webbing take-up device according to a second embodiment of the present invention.

FIG. 12 is a longitudinal sectional view partially showing a webbing take-up device according to a second embodiment of the present invention.

FIG. 13 is an exploded perspective view partially showing a conventional webbing winding device.

FIG. 14 is a front view showing a conventional webbing take-up device, partially cut away.

FIG. 15 is a front view showing an operation state of the conventional webbing take-up device, partially broken away.

[Explanation of symbols]

 Reference Signs List 12 webbing take-up device 16 take-up cylinder (spool) 24 adapter (spool) 28 shaft (spool) 29 spool 34 small spring 36 spring seat 50 brake spring 60 pawl 64 large spring 72 webbing take-up device 74 rotor

Claims (2)

[Claims] 1. A spool capable of winding webbing, a first spiral spring having an inner end fixed to the spool and elastically restoring the spool in the webbing winding direction, and an outer end of the first spiral spring. A rotating body that is rotatable coaxially with the spool, and an inner end that is secured to the rotating body, and that provides a larger elastic force in the webbing winding direction than the first spiral spring to the rotating body and the first spiral spring. A second spiral spring that transmits to the spool via the spool, a pawl that engages with the rotating body when it is detected that the webbing is mounted on an occupant, and prevents rotation in the webbing winding direction; When the pawl is disengaged from the rotating body and the rotating body rotates relative to the spool in the webbing winding direction by the elastic force of the second spiral spring, the pawl is wound around the spool and rotated. The webbing retractor and having a brake spring for applying a frictional resistance to the rotation of the. 2. A spool for a brake spring, which is disposed between the rotating body and the brake spring, when the relative rotation amount of the spool in a direction opposite to the elastic force direction of the second spiral spring is less than a predetermined amount. The webbing take-up device according to claim 1, further comprising a rotor that prevents winding around the webbing.