JPS5973347A - Seat belt taking-up apparatus - Google Patents

Abstract

PURPOSE:To eliminate the oppressive feeling in installation of a seat belt by controlling a belt taking-up motor by a slick sensor for detecting the movement of a slip joint which is caused by the slack of the belt and a buckle installation sensor. CONSTITUTION:A motor is installed ontoa retractor of a seat belt 12, which is taken-up by the drive of the motor. A slip joint 40 through which the belt 12 is passed is made rotatable by a bolt 44, and a coil spring 60 operates to return the slip joint 40 to the position shown in the figure. At the position shown in the figure where a belt tension does not act, contacts 71 and 72 are bought into conduction to constitute a slick sensor 70. An installation sensor 52 is installed onto a buckle 50, and the motor is controlled by the both sensors. When a slack is generated on the belt, the motor is driven to take-up the belt. Therefore, a drive is free from oppressive feeling, and the protection performance is not reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle seat belt retractor.

2. Description of the Related Art Seatbelt retracting devices that are installed in a vehicle together with a seatbelt and that fully automatically retract the seatbelt when the seatbelt is used by an occupant and when the seatbelt is removed from the occupant have been widely known. A mainspring spring is generally used as a driving means for this winding device. One end of the mainspring spring is fixed to the main body of the winding device 9 attached to the car body, and the other end is fixed to the winding section 9 of the seat belt retractor. Belt winding force is constantly applied.

When attaching a seat belt to an occupant using such a conventional retractor, a large amount of force is required to pull out the seat belt against the force of the main spring, and the seat belt is A drawback is that the force required to pull out the seat belt increases as the belt is pulled out.

In addition, when the seat belt is worn, the winding force of the spring is acting on the seat belt, so
This has the disadvantage that it gives a feeling of pressure to the seatbelt wearer.

In view of the above-mentioned drawbacks of the conventional device, the present invention is capable of retracting the seat belt only when the seat belt is worn, when the seat belt loosens when the seat belt is worn, and when the seat belt is removed from the occupant. Moreover, it is an object of the present invention to provide a seat belt retractor which can perform a retracting operation when the seat belt is loosened sensitively and without generating any abnormal noise with a simple configuration.

In order to achieve the above object, the present invention includes a drive means for winding up a seat belt supported via a slip joint, an optical film sensor for detecting whether the seat belt is attached to or detached from an occupant, and a seat belt. Based on signals from a slack sensor that detects slack, the attachment/detachment sensor, and the slack sensor, the drive is performed only when the seatbelt is loosened when the seatbelt is fastened, when the seatbelt is fastened, and when the seatbelt is removed from the occupant. Looking down at the drive control means for driving the slack sensor, there is a base terminal fixed to the vehicle body side, and a movable contact terminal integrally formed on the spring that assists the movement of the slip joint as the seat belt becomes slack. The present invention provides a seat belt retracting device having a feature of t%.

Embodiment 'ff' of the present invention will be described below with reference to the drawings.

In Figures 1 and 2, 10 is the retractor body;
This retractor main body 10 is fixed to the vehicle body by a bolt (not shown) inserted through the hole 10A. The retractor main body 10 rotatably supports a belt winding shaft 11 having a recess J')-r 11A and a shell passer 11B.

A loop portion 12A is sewn to one end side of the seat belt 12 for the three-point seat belt system, and the loop portion 12A is sewn into the recess 11A of the belt winding shaft 11.
By inserting the rod 13 into A, the seat belt 12 is prevented from coming off from the belt winding piece 111.

A motor 20 is attached to the retractor body 10 as a driving means for retracting the seat belt.
Here, the output shaft 21 of 0 is directly operatively engaged with the belt winding shaft 11.

The belt winding shaft 11 is rotated counterclockwise in FIG. 2 by driving the motor 20. On the other hand, when the first seat belt 12 is pulled out from the retractor main body 10, the output shaft 21 of the motor 20 idles due to the pulling force, and the belt winds!
The shaft 11 rotates in the clockwise direction in FIG.

A vibrator 31 is swingably supported on a bracket 30 fixed to the retractor main body 10.

This pendulum 31 swings and pushes up the pawl 32 when a shock occurs due to a vehicle collision or the like. This p, I? Gear 3 in which protrusion 32A of Raul 2 is fixed to belt winding 9 shaft 11
3, and the belt winding shaft 110 rotations are locked.

Seat belt 12 pulled out from retractor body 10
As shown in FIG. 3, the retractor body 10 is inserted into and supported by a slip joint 40 provided above the retractor body 10, and is further connected to an unillustrated anchor attached to one side of the passenger seating portion through a tongue plate 50. The tongue plate 50 is removably attached to a buckle 51 connected to the other side of the passenger seating portion 9, and by connecting the tongue plate 50 to the nokkle 51, the seat belt 12 is fastened to the passenger. The buckle 51 has a built-in buckle sensor 52 that detects whether the tongue plate 50 and the buckle 51 are connected. It consists of

The slip joint 40 has a ring part 41 having a hole 41At through which the seat belt 12 passes, and a plate part 42 attached to the ring part 41. The plate part 42 is also shown in FIG. As shown, it has a hole 42Ai. The hole 42A of the plate portion 42 is rotatably fitted into a bolt 44, which is a pivot attached to the vehicle body frame 43. Shito 4
It is freely rotatable around 4. The bolt 44 is covered with a collar 45, and the collar 45 is attached to the bolt 44.
It is clamped and fixed between a stepped portion 44A formed in the body frame 43 and the vehicle body frame 43. The outer periphery of the collar 45 has the collar 4
An insulating collar 46 that wraps around 5 is fixed. A flange portion 46A extending radially outward of the insulating collar 46 is integrally formed.

A coil spring 60 having a larger inner coil diameter than the outer circumference of the insulating collar 46 is disposed on the outside of the insulating collar 46 substantially concentrically with the insulating collar 46 . The fixed end 60A of the coil spring 60 is fixed to the flange portion 46A of the insulating collar 46, and the movable end 60B of the coil spring 60 is fixed to the cylindrical protective cover 61 fixed to the plate portion 42 of the slip joint 40 with a screw. It is attached to the hole 61A. The coil spring 60 moves from the position shown in FIG. 5 to the position shown in FIG.
It plays a role in assisting the movement to the state shown in the figure. Therefore, when the seat belt 12 becomes slack, the slip joint 40 is quickly returned to the position shown in FIG. 3 by its own weight and the assisting force of the coil spring 60.

A base terminal 71 made of a conductor is provided on the outer peripheral surface of the insulating collar 46 by means of adhesion, plating, etc., and a movable contact terminal 72 for the base terminal 71 is integrally provided near the movable end 60B of the coil spring 60. is formed. The base terminal 71 and the 0T moving contact terminal 72 constitute a slack sensor 70 that detects slack in the seat heald 12.

In FIG. 1, a motor 20 serving as a seatbelt retractor drive means is driven by current supplied from a battery 80, and the supplied current is controlled by a controller 81. The controller 81 receives the signal from the buckle sensor, that is, the detachable sensor 52, and the signal No. 41 from the slack sensor 70.
The controller 81 is configured to drive the motor 20 based on the signals from these sensors 52, 70 only when the seat belt 12 becomes slack when the seat belt is worn and when the seat belt 12 is released from the occupant. There is.

Next, the operation of the seatbelt retractor having the above structure will be explained in detail in relation to the state of use of the seatbelt.

The drive of the motor 20 is controlled by a controller 81 as shown in the control table below.

In other words, the motor 20 is driven when the buckle connection signal (OFF→ON) from the buckle sensor 52 is input to the controller 81, that is, when the belt is attached. When the signal from the buckle sensor 52 is ON, that is, when the belt is fastened, the seatbelt slack detection signal (OF) generated from the slack sensor 70 when the occupant moves is
The motor 20 is driven only when the signal (F→ON) is input to the controller 81. Furthermore, the motor 20 receives a buckle release signal (ON→OFF) from the buckle sensor 52.
) is input to the controller 81, it is driven. The motor 20 is driven only in the above three states, and is not driven in any other state.

When the motor 20 is driven 1, the output 111 of the motor 20
121, the belt winding shaft 11 rotates counterclockwise in FIG. 2 to wind up the seat belt 12.

The drive of the motor 20 is stopped when a set time has elapsed by a set timer (not shown).

To explain the operation of the slack sensor 70 in more detail, when no tension is applied to the seat belt 12, the slip joint 40 is kept in the position shown in FIG. 3 by its own weight, and at this time, the movable contact terminal 72 is The slack sensor 70 is turned on by contacting the terminal 71.

When the occupant wears the seat belt 12, the seat belt 12
The shoulder belt portion 12B moves to the position shown in FIG. Move to the position shown in the diagram. Therefore, the movable contact terminal 72 formed on the coil spring 60 separates from the base terminal 71 formed on the outer peripheral surface of the insulating collar 46, and the slack sensor 70 is turned off.

When an occupant is wearing a seatbelt, if the occupant pulls out the seatbelt 12 by moving on the seat and attempts to return to the initial position, the shoulder belt portion 1 of the seatbelt 12
2B becomes slack, and the shoulder belt portion 12B becomes in the state shown by the dotted chain line in FIG. 3. At this time, the seat belt 12 loses its tension, so the slip joint 40 rotates around the bolt 440 times due to its own weight and the spring force of the coil spring 60! Rotate ll and return to the position shown in FIG. At this time, as the movable contact terminal 72 contacts the base terminal 71, the slack detection signal (OFF→ON) from the slack sensor 70 is transmitted to the controller 81.
is sent to the motor 20 according to a command from the controller 81.
is driven.

As a result, the seat belt 12 is wound around the belt winding shaft 11, and the slack in the seat belt 12 is eliminated. Then, the driving of the motor 20 is stopped by the set timer.

Note that when the seat belt 12 is pulled out, the output shaft 21 of the motor 20 rotates idly together with the belt winding shaft 11 with a slight resistance against the main body of the motor 20, so the seat belt 12 has a small amount of tension when the seat belt 12 is pulled out. It takes.

Therefore, the seat belt 12 will not be pulled out when unnecessary. In addition, when the seat belt is fastened), the slack detection signal (OF
Since the motor 20 is not driven unless the state (F→ON) is obtained, the occupant is unlikely to feel pressured by the seatbelt 12. On the other hand, when the slack of the seat belt 12 exceeds a predetermined value, the slack sensor 70 operates, and the seat belt 12 is quickly retracted by driving the motor 20 according to the command from the controller 81, thereby eliminating the slack of the seat belt 12. removed. Therefore, the occupant retention performance of the seat belt 12 does not deteriorate.

Figure 6 shows the relationship between the seatbelt tension and the seatbelt pull-out stroke. In the figure, the solid line indicates the characteristics of the above-mentioned example device, and the broken line indicates the conventional spring-type seatbelt retractor. Indicates the characteristics of the device. Further, the arrow in the figure indicates the direction in which the seat belt is pulled out. This sixth
From the figure, it is possible to understand the superiority of the above embodiment device over the conventional type seat belt retractor.
In the embodiments described above, the driving of the motor is stopped by a set timer, but the tension of the seat belt may be detected and the driving of the motor may be stopped based on the detected signal.

As described above, according to the present invention, the belt winding force υ is reduced to zero when attaching and detaching the seat belt, so that the seat belt attaching and detaching work can be easily performed.

Also, when wearing a seatbelt, the seatbelt is retracted only when the seatbelt is loosened beyond a certain level, so it is possible that the occupant is wearing a seatbelt. When the seat belt is not pulled out most of the time, such as when the passenger is exercising at a seat, the belt winding force is zero, and the occupant feels no pressure. Therefore, a comfortable seatbelt feeling can be obtained. On the other hand, when the seatbelt becomes slack by a predetermined amount or more, the seatbelt is quickly wound up and the slack in the seatbelt is removed, so that the ability of the seatbelt to retain the occupant does not deteriorate.

In particular, the slack sensor in the device of the present invention is
, ll, and a movable contact terminal integrally formed with a spring that assists the movement of the slip joint as the seatbelt slackens. The movement of the slip joint can be quickly performed by the spring action, thereby making it possible to quickly start the winding operation of the seat belt. Moreover, since the movable contact terminal is integrally formed with the blade, the number of parts is reduced to nine parts in a compact four-conductor structure.

[Brief explanation of the drawing]

Figure 1 shows an embodiment of the seat belt retractor according to the present invention. Figure 2 is a schematic sectional view taken along line r-1 in Figure 2 near the tractor body. Figure 2 is the IJ shown in Figure 1. 3 is a sectional view taken along line II-n in FIG. 1 near the tractor main body, and FIG. 3 is a sectional view taken along line l1l-1[1tQ in FIG. Figure 4 shows \N# in Figure 3 near the slip joint shown in Figure 3.
? 5 is a sectional view showing the operating state of the slip joint and slack sensor when the seatbelt is pulled out, and FIG. 6 is a sectional view showing the seatbelt tension and seatbelt tension of the seatbelt retractor according to the present invention when the seatbelt is pulled out. FIG. 3 is a characteristic diagram showing the relationship with the stroke in comparison with the prior art. In the figure, 12 is a seat belt, 20 is a motor as a H&lJ means, 40 is a snail, 52 is a buckle sensor as an attachment/detachment sensor, 70 is a slack sensor, 71 is a base terminal 172 is a movable contact terminal, and 81 is a controller. Each is shown below. Japan Motor Vehicle Parts General Research Institute Patent Attorney Patent Attorney Akira Aoki Patent Attorney Kazuyuki Nishidate Patent Attorney Kuni Nishioka Akira Yamaguchi Figure 1 Figure 2 74- Figure 4 ■ Funeral Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1. A drive means for winding up a seat belt supported via a slip joint, an attachment/detachment sensor for detecting whether the seat belt is attached to or detached from the occupant, and a sensor for detecting slack in the seat belt. Based on the signals from the slack sensor, the attaching/detaching sensor, and the slack sensor, the 1M moving means tj is activated only when the seat belt is fastened, when the seat belt loosens when the seat belt is fastened, and when the seat belt is released from the seat belt by the occupant. comprising drive control means for pivoting;
The slack sensor is characterized by comprising a base terminal fixed to the vehicle body side and a movable contact terminal integrally formed with a spring that assists the movement of the slip joint as the seat belt becomes slack. Seatbelt retractor. 2. In the seatbelt winding device according to claim 1, the spring is a coil spring wound around a shaft that pivots on the slit joint relative to the vehicle body; One end of the spring is secured to a vehicle body and the other end is secured to a slip joint, and a portion of the coil spring near the locking end on the slip joint side constitutes a movable contact terminal. Removal device.