JPH045404Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Field of application of invention] The present invention relates to a webbing take-up force suppressing device.

[Background technology]

In a seat belt device, a restraining webbing that is attached to an occupant is wound onto a winding shaft with a biasing force, thereby bringing the webbing into close contact with the occupant.

However, when the vehicle is running, the occupant feels pressure to take up the webbing through the webbing, causing fatigue. For this reason, various webbing take-up force suppressing devices have been proposed in the past that suppress the webbing take-up force after the webbing is worn, thereby eliminating the feeling of pressure on the occupant.

However, with such conventional webbing take-up force suppressing devices, after the webbing has been pulled out from the take-up shaft by a predetermined length corresponding to the length of the webbing worn by the passenger, the webbing is automatically taken up by a small amount onto the take-up shaft. Therefore, the winding force of the webbing is suppressed. For this reason, if the occupant is not seated correctly on the seat with the webbing attached, and the webbing is attached with a gap between the occupant and the seat, and from this state the occupant is moved slightly forward, This causes a state in which the winding force is inhibited, which causes a large gap to be formed between the occupant and the webbing when the occupant assumes an actual running position. These conventional problems are caused by the inability to properly detect the state in which the occupant is wearing the webbing, and the conventional detection means uses a planetary gear mechanism to decelerate the rotation of the take-up shaft and then slows down the rotation of the take-up shaft. Although the structure is complicated, it is impossible to accurately detect the rotational position of the winding shaft.

[Purpose of invention]

The present invention provides a webbing take-up force suppressing device that can reliably and easily detect when the occupant is in the normal driving position, and can minimize the gap between the webbing and the occupant. It is a purpose.

[Summary of the idea]

In the webbing take-up force suppressing device according to the present invention,
The wire is wound around a connecting shaft that rotates in accordance with the rotation of the winding shaft, and the webbing is drawn out.The length of the winding of the wire is changed in accordance with the winding, and this change in length is detected by a detection means to operate the holding mechanism. This holding mechanism prevents the take-up shaft biasing elastic body from applying elastic force to the take-up shaft.

[Example of idea]

1 to 3 show a webbing retractor 10 to which a webbing retractor force suppressing device according to the present embodiment is applied.

In this webbing retractor 10, the frame 12
is fixed to the vehicle body 16 with mounting bolts 14.

Leg plates 18 and 20 that are bent at right angles from both sides of the frame 12 and extended parallel to each other support the vicinity of both ends of a winding shaft 22, and a passenger is restrained at the center of the winding shaft 22. The base end of the webbing 24 is fixed. A tongue plate 25 is attached to the tip of the webbing 24 (see FIG. 4), and the space between the tongue plate 25 and the winding shaft 22 serves as a mounting portion for an occupant (not shown).

A sheet 26 is fixed to the outside of the leg plate 20, and a connecting shaft 30 is inserted through a circular hole 28 formed in this sheet 26.
is connected to the end of the winding shaft 22 to rotate the connecting shaft 30 integrally with the winding shaft 22. The winding shaft 22 and the connecting shaft 30 may be formed integrally.

The connecting shaft 30 is made of an insulating material, and has a helical shaft 32 and a flat shaft 34 in the middle thereof, and a small diameter shaft 36 is formed at the tip of the flat shaft 34.

A rectangular hole 40 formed in the shaft core of the gear wheel 38 is fitted into the flat shaft 34, so that the gear wheel 38 is connected to the winding shaft 22 via the connecting shaft 30.
It is designed to rotate integrally with the A ratchet gear 42 is carved on the outer periphery of the gear wheel 38, and a boss portion 44 formed coaxially with the ratchet gear 42 has a slit 4 tangentially formed therein.
6 is bored and the inner end of the mainspring spring 48 is inserted. The outer end of this mainspring spring 48 is connected to the leg plate 2.
It is locked to a cover 50 attached to the outside of 0. Therefore, this main spring 48 is connected to the winding shaft 2.
When the rotation of this gear wheel 38 is stopped, the winding shaft 22
The webbing winding force becomes inhibited.

An intermediate portion of a conductive wire 52 is wound around a helical groove formed in the helical shaft 32 of the connecting shaft 30 . One end of this wire 52 is fixed to the outer periphery of the helical shaft 32, and the helical shaft 32 and gear wheel 38
It is adapted to come into contact with a slip ring 54 which is held between. This slip ring 54 is always pressed against one end of the wire 52 by the biasing force of the rubber material 55 to maintain electrical contact. A wire 56 connected to the slip ring 54 is connected to a vehicle power source (not shown).

On the other hand, the other end of the wire 52 is unwound from the helical shaft 32, wound around contact rings 59A and 59B which are pivotally supported on the sheet 26 by a bracket 58, and then wound onto the winding shaft 60.
It is wound up. The wire rod 52 is wound around the winding shaft 60 by the biasing force of a torsion coil spring 61. Therefore, the wire 52 is wound onto the helical shaft 32 and drawn out in accordance with the rotation of the winding shaft 22, and the contact position with the contact rings 59A, 59B changes.

This contact ring 59A is made of metal, and one end of a wire rod 62 is connected thereto. This wire 62 is the ammeter 6
3 to the vehicle power supply. Therefore, this ammeter 63 detects a change in current according to the rotation of the winding shaft 22, and serves as a webbing extraction amount detection means for detecting the amount of the webbing 24 unreeled.

On the other hand, the seat 26 has a pin 66 that connects the rocker arm 6.
8 is pivoted. A pawl 70 is pivotally supported at one end of the rocker arm 68 by a pin 72.
This pawl 70 is urged in a direction toward the ratchet gear 42 by the urging force of a torsion coil spring 74.

A suction plate 76 provided at the other end of the rocker arm 68 corresponds to a solenoid 78 fixed to the cover 50. When this suction plate 76 is attracted by a solenoid 78, the rocker arm 68 engages the pawl 70 with the ratchet gear 42.

In this meshed state, the ratchet gear 42 stops rotating in the webbing take-up direction, so the biasing force of the mainspring spring 48 does not act on the take-up shaft 22, and the webbing take-up force is suppressed.
Since the pawl 70 is rotatable with the locker arm 68, the attachment error of the locker arm 68 is absorbed and the pawl 70 is reliably engaged with the ratchet gear 42.

The rocker arm 68 urges the pawl 70 in a direction away from the ratchet gear 42 by the urging force of a torsion coil spring 80. Further, the solenoid 78 constitutes a holding mechanism together with the ratchet gear 42 and the pawl 70, and forms a state in which the winding force of the winding shaft is inhibited.

The solenoid 78 is driven by the control device 64 and the suction plate 7 of the rocker arm 68 is driven by the vehicle power supply.
Aspirate 6.

The control device 64 controls the state in which the webbing is attached, that is, the state in which the webbing 24 is buckled up by the occupant (webbing pull-out length t=0 in FIG. 5).
is detected by the ammeter 63, and the maximum unwinding position of the winding shaft during a predetermined time _t0 (for example, about 10 seconds) from this state is memorized, that is, the minimum withdrawal amount _l0 , and this After an elapsed time t _{0 ,} the solenoid 78 is sucked when the take-up shaft reaches the webbing maximum unwinding position l ₀ or a length of the webbing pull-out position l ₀ +Δl that exceeds l ₀ .

Further, as shown in FIG. 4, the control device 64 is connected to a buckle switch 84 in a buckle device 82 with which the tongue plate 25 is engaged, so that the tongue plate 25 engages with the buckle 82 and the passenger can attach the webbing 24. When the state is reached, it closes and sends a signal to the control device 64.

The operation of this embodiment configured in this way will be explained.

When the occupant is not wearing the webbing, the webbing 24 is wound onto the take-up shaft 22 by the maximum amount, and from this state the occupant pulls out the webbing 24 and attaches it.

When the occupant pulls out the webbing 24 after the buckle and tongue are latched, the ammeter ₆₃ detects the amount of pullout, and as shown in _FIG . 24, the tongue plate 25 attached to a part of the webbing is engaged with a buckle device 82 attached to the vehicle body. When the driving position is entered after the back-up state, the amount of webbing pulled out becomes the minimum). 64 remembers. The occupant enters the driving position after putting on the webbing, but it is preferable that a predetermined time _t0 elapses immediately before the occupant assumes the driving position, and after the elapse of the predetermined time _t0 , when the webbing is in the maximum retraction state or After that, if the occupant pulls out the webbing 24 by more than a certain amount (△l) due to movement due to abdominal breathing, etc., during the subsequent retraction operation, l ₀ +
At the position Δl, the control device 64 operates the solenoid 78, so the pawl 70 engages with the ratchet gear 42, and the rotation of the take-up shaft 22 in the webbing take-up direction is stopped, resulting in a webbing take-up force inhibited state.

As a result, the winding force of the mainspring spring 48 is not applied to the occupant, so that the occupant can enjoy a comfortable driving condition. Furthermore, when the occupant moves his or her upper body significantly to operate the instruments in front of the passenger seat while the vehicle is running, the ammeter 63 detects the rotation of the take-up shaft and de-energizes the solenoid 78. As a result, the occupant can move his or her upper body using the biasing force of the mainspring spring 48 in the same way as in a normal retracting device, and when the occupant returns to the original driving position, the webbing will be pulled out to the position l ₀ + △l. The solenoid 78 is energized and the webbing take-up force is inhibited.

When the occupant releases the webbing, the buckle switch 84 opens, which causes the control device 64 to de-energize the solenoid 78 and turn the take-up shaft 2
The biasing force of the mainspring spring 48 acts on the webbing 24 due to the biasing force of the mainspring spring 48.
The maximum amount of can be wound onto the winding shaft 22, resulting in a fully wound state.

In the above embodiment, the control device 64 is configured to memorize the maximum unwinding position within the time t ₀ after the webbing 24 is pulled out from the fully wound state, but the maximum unwinding position within the time t 0 after the tongue plate 25 is engaged with the buckle device 82 is stored. The configuration may be such that the maximum rewind position within ₀ hours is stored, or the configuration may be such that the maximum rewind position of the webbing is stored within a predetermined time after the webbing is pulled out when the webbing is attached. In addition, to detect changes in the length of the wire 52 wound around the helical shaft 32, it is possible to use not only an ammeter as described above but also a change in capacitance, etc.
The material is not limited to conductive material, and may have a structure in which a magnetic material is attached to a non-conductive material.

[Effect of idea]

As explained above, in the present invention, the webbing pull-out length is detected by detecting the change in the length of the wire wrapped around the connecting shaft, so that the normal driving posture of the occupant can be accurately detected with a simple structure.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a webbing retractor to which an embodiment of the webbing retracting force suppressing device according to the present invention is applied, FIG. 2 is a sectional view taken along the line -- in FIG. 1, and FIG. Figure 4 is an explanatory diagram showing the relationship between the tongue plate and the buckle device, Figure 5 is an exploded perspective view of
The figure is a diagram showing the correspondence between webbing pull-out length and elapsed time. DESCRIPTION OF SYMBOLS 10... Webbing winding device, 22... Winding shaft, 24... Webbing, 42... Ratchet gear, 48... Mainspring spring, 52... Conductive wire material.

Claims (1)

[Claims for Utility Model Registration] (1) A winding shaft that winds up occupant restraint webbing, an elastic body that biases this winding shaft in the webbing winding direction, and a rotation of the winding shaft that is transmitted. a connecting shaft; a wire wound around the connecting shaft, the length of which is wound around the connecting shaft changes as the connecting shaft rotates;
A webbing pull-out amount detection means detects a change in the winding length of the wire rod to detect the webbing pull-out amount, and the biasing force of the elastic body is suppressed when the passenger is driving by receiving an output from the webbing pull-out amount detection means. A webbing take-up force suppressing device comprising: a holding mechanism for holding a webbing; (2) The holding mechanism stores the maximum unwinding position of the webbing within a predetermined time after the webbing is pulled out when the occupant is wearing the webbing, and after the predetermined time elapses, the holding mechanism stores the webbing by a predetermined amount corresponding to the appropriate slack amount after the predetermined time has elapsed. The webbing take-up force according to claim 1 of the utility model registration claim, characterized in that the webbing has a drive means for suppressing the biasing force of the elastic body in a state where the webbing is further pulled out from the webbing maximum unwinding position. Deterrent device.