JP3508880B2 - Pull-out prevention device for vehicle seat belt - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for restraining a seat belt for restraining an occupant who is seated in a vehicle when the seat belt receives a force in the pulling direction in an emergency.

[0002]

2. Description of the Related Art In an emergency such as a collision, in order to restrain an occupant against a large forward forward inertial force associated with a sudden deceleration, a seat belt having a front end of the occupant bridged and one end locked to a vehicle body is reeled. In the case of an emergency, the reel can be wound up or pulled out from the reel, and when a large pulling-out acceleration is applied to the seat belt, the reel is fixed with a claw to lock the pull-out of the seat belt. The lock retractor has been conventionally used.

In such a conventional emergency locking retractor, in order to enhance restraint of the seat belt in an emergency, the explosive force of the explosive is used to forcefully retract the seat belt. Although there was a pretensioner, it was difficult to use it repeatedly because the powder had to be loaded after the emergency operation.

There has been a device using an electric motor as a drive source so that it can be repeatedly used (see Japanese Patent Application Laid-Open No. 4-314651).

[0005]

[Patent Document 1] Japanese Unexamined Patent Publication No. 4-314651 discloses a conventional emergency locking retractor which works after the completion of winding of a seat belt by an electric motor to lock the seat belt pulled out. Because,
After the seat belt is locked, the seat belt wound around the reel is further tightened by the tension in the pull-out direction and pulled out for a certain length, and as a result, the winding effect is significantly reduced.

In particular, an electric motor has a remarkably small output per unit weight and unit volume as compared with an explosive type pretensioner. Therefore, increasing the size of the electric motor to increase the output of the electric motor poses a problem in mounting on a vehicle. The increase was inevitable.

[0007]

SUMMARY OF THE INVENTION The present invention relates to an improvement of a vehicle seat belt withdrawal prevention device which overcomes the above problems, and is connected to one end of a seat belt for restraining an occupant in a vehicle. The reel that has been mounted, the clamp means that is located on the side where the seat belt is pulled out from the reel and that clamps the seat belt and regulates the pulling out of the seat belt, the shaft of the reel and the motor rotating shaft are connected, and the seat An electric motor that winds and pulls out a belt, and an electric motor casing is rotatably supported around a frame that pivotally supports the reel shaft about the motor rotation shaft, and a seat belt is wound on the reel. Torque bearing means for bearing the winding torque acting on the casing of the electric motor, and the clamp hand by the operation of the torque bearing means. It is characterized in that a driving means for operating.

Since the present invention is configured as described above, in an emergency, when the electric motor operates so as to wind the seat belt tensioned in the pull-out direction onto the reel, the casing of the electric motor is wound. A torque in a direction opposite to the take-up direction is received, the torque is carried by the torque carrying means, the casing of the electric motor rotates in a direction opposite to the take-up direction, and the drive means is provided by the reverse rotation of the electric motor casing. The clamp means operates in accordance with the above operation, and the pulling tension of the seat belt that tries to tighten the seat belt wound on the reel is borne by the clamp means, and the seat belt on the reel is tightened. The withdrawal of the seat belt is blocked in advance.

As described above, in the present invention, the large pulling force acting on the seat belt in an emergency is borne by the clamp means, and the large pulling force does not act on the reel, so that the seat belt wound around the reel is prevented. The seat belt is prevented from being pulled out by tightening, and the seat belt restraint performance is high.

Further, according to the present invention, since the pulling load acting on the seat belt is borne by the torque bearing means and the clamping means is operated by utilizing the bearing force, the structure is simplified and the number of parts is reduced. It is possible to reduce the cost, and it is possible to greatly reduce the cost and reduce the weight.

Further, by constructing the present invention as set forth in claim 2, the torque bearing means and the driving means can be simplified, and further cost reduction and weight reduction can be promoted.

[0012]

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in FIGS. 1 to 6 will be described below.

As shown in FIGS. 1 and 2, holes 2a and 3a (hole 3a is not shown) are formed in one side wall portion 2 and center side wall portion 3 of a frame 1 having a Y-shaped cross section. In the state where the reel 7 is loosely fitted between the one side wall portion 2 and the central side wall portion 3, the bush 8 is fitted into the hole 2a of the one side wall portion 2, and the reel shaft 9 is attached to the bush 8 and the reel 7. Is inserted and rotatably supported on the central side wall portion 3 via a bearing 10.

An electric motor 11 is interposed between the central side wall portion 3 and the other side wall portion 4 of the frame 1, and a motor rotating shaft 12 of the electric motor 11 is connected to the reel shaft 9 by a joint (not shown) or the like.
A casing short cylindrical portion concentric with the motor rotating shaft 12 is directly connected to the other side portion of the motor casing 13 of the electric motor 11.
14 is formed, and the casing short cylindrical portion 14 has a bearing 15
The electric motor 11 is rotatably and rotatably supported by the other side wall portion 4 via the electric motor 11 by a current controlled by a seat belt control device (not shown), so that the traveling speed of the vehicle, the brake pedal force, the gear stage, etc. The seat belt 24 is wound around the reel 7 with the tension set accordingly.

Further, a motor arm 17 is provided on the motor casing 13 so as to project in a direction away from the bottom wall portion 6 of the frame 1, and a compression coil spring 20 is interposed between the motor arm 17 and the bottom wall portion 6 of the frame 1. The motor casing 13 is urged to rotate in the A direction by the spring force of the compression coil spring 20.

Further, a clamp shaft 21 is rotatably pivoted on the upper part of the one side wall part 2 and the central side wall part 3, and the clamp shaft 21 is rotatably attached.
The clamp arm 22 is spline-fitted to the 21 (key fitting is also possible), and the clamp receiving piece 23 is integrally mounted on the back wall portion 5 opposite to the clamp arm 22 with the seat belt 24 interposed therebetween.
A base end of a clamp arm 18 is integrally fitted to the clamp shaft 21, and both ends of a connecting rod 19 are rotatably pivotally attached to a tip end of the clamp arm 18 and a tip end of a motor arm 17, respectively. The link means 16 is constituted by the arm 18 and the connecting rod 19.

An emergency locking mechanism is arranged on the one side wall portion 2 on the left side of FIG. 1, and the emergency locking mechanism is constructed as follows.

In FIG. 2, a ratchet 25 is integrally provided at one end of the reel shaft 9, and a shaft end 9a protruding outward from the ratchet 25 has a center hole 26a of a tie plate 26.
, The center hole 27a of the clutch body 27 and the center hole 28a of the retainer 28 are sequentially fitted, the inertia mass 29 and the flywheel 30 are sequentially fitted to the outer periphery of the retainer 28, and the flywheel 30 is frictionally engaged. The tie plate 26, the clutch main body, and the screw 32, which is applied with the stop plate 31, penetrates the friction locking plate 31, and is screwed to the shaft end portion 9a of the reel shaft 9.
27, retainer 28, inertia mass 29, flywheel 30
A friction locking plate 31 is attached to the shaft end 9a of the reel shaft 9.

The hole 26b at the end of the tie plate 26 and the hole 33a of the pawl 33 are fitted to the pin 34 fitted to the one side wall portion 2, so that the tie plate 26 is fixed and the pawl is fixed.
The pin 33 swings around the pin 34, and is engaged with the ratchet 25 so as to be disengageable.

Further, both ends of the clutch return spring 35 are locked in the locking portion 26c of the tie plate 26 and the locking hole 27b of the clutch body 27, and the spring force of the clutch return spring 35 causes the clutch body 27 to move to the position shown in FIG. 2 and FIG. 5, it is biased in the A direction.

Furthermore, a compression coil spring 36 is interposed between the spring receiving protrusion 28b of the retainer 28 and the inner surface of the outer peripheral portion 29a of the inertia mass 29. The spring force of the compression coil spring 36 causes the inertia mass 29 to move to D Biased in the direction.

Further, the inertia mass 29 is provided with a protrusion 29b which can be engaged with the engagement hole 31a of the friction engagement plate 31, and is engaged with the protrusions 28c and 28d of the retainer 28 in the C and D directions. A movable notch 29c and a square hole 29d are formed, and an outer peripheral portion 29a is formed with a locking claw 29e which can be removably fitted with a locking tooth 27b of the clutch body 27.

Further, a projection 33b is formed on the pawl 33, and the projection 33b is engaged with an engagement hole 27c of the clutch body 27. When the clutch body 27 rotates in the B direction, the tip claw 33c of the pawl 33 is ratcheted. 25 can be engaged.

Further, the lock activation mechanism 37 includes a base piece 38 integrally mounted on the one side wall portion 2, a pendulum 39 capable of tilting on the base piece 38 by detecting an acceleration in the longitudinal direction of the vehicle. pendulum
The ratchet 25 and the tie plate 26 or the locking claws 40 are sealed with a cover 41 (see FIG. 1). The locking claws 40 can be engaged with the locking teeth 30a of the flywheel 30 when the tilting of the flywheel 30 occurs. There is.

Since the embodiment shown in FIGS. 1 to 6 is configured as described above, the lock actuating mechanism 37 does not start in a state where a large acceleration in the front-rear direction is not generated, so that the emergency locking mechanism is activated. Does not operate and pull-out tension is applied to the seat belt 24, the reel 7 rotates in the B direction, and the seat belt 24 wound around the reel 7 is pulled out.

When the occupant wears the seat belt 24 and runs the vehicle, the seat belt control device supplies a current to the electric motor 11 according to the running speed of the vehicle, the brake pedal force, the gear position, and the like. The seat belt 24 is wound around the reel 7 by the torque generated in the electric motor 11 in accordance with the above condition.

In the state where the seat belt 24 is wound around the reel 7 with a certain tension (see FIG. 3) in this way, when an emergency occurs and a large pulling tension is applied to the seat belt 24, the above-mentioned emergency occurs. The locking mechanism operates as described in detail below, but with current controlled by the seat belt controller at the same time or prior to this, as illustrated in FIG. A large torque is generated in the electric motor 11 to rotate the motor rotating shaft 12 in the A direction, and the motor rotating shaft 12 directly connected to the reel 7 and the reel shaft 9 is greatly pulled by the pulling tension of the seat belt 24. Motor casing as a result of not being able to rotate in any direction
By its reaction, 13 overcomes the spring force of the compression coil spring 20 and rotates in the B direction, and this movement is transmitted to the clamp arm 22 via the link means 16, and from the state shown in FIG. 3 to FIG. As shown, the clamp arm 22 is B
The seat belt 24 is swung in the direction and clamps the seat belt 24 in cooperation with the clamp receiving piece 23, and the seat belt 24 is fixed so as not to be pulled out upward.

When a large pulling tension is applied to the seat belt 24, as shown in FIG. 5, the flywheel 30
Stops due to its inertia, the rotational force in the B direction applied to the reel 7 is transmitted to the reel shaft 9 and the retainer 28, and the inertia mass 29 tries to rotate in the B direction around the protrusion 29b, so that the compression coil spring 36 Moves in the C direction by overcoming the spring force, and engages the locking claw 29e of the inertia mass 29.
Engages with the locking teeth 27d of the clutch body 27,
27 is also rotated in the B direction, and by the rotation of the clutch main body 27 in the B direction, the projection 33b of the pawl 33 engaged with the engagement hole 27c of the clutch main body 27 swings in the A direction, and the tip claw of the pawl 33 is rotated.
33c engages with the ratchet 25, and the reel 7 is locked so as not to rotate.

Then, a large pulling tension acts on the seat belt 24, and the seat belt 24 wound around the reel 7
If the emergency lock mechanism is activated or at the same time as the clamp arm
22 swings in the B direction, the seat belt 24 is strongly clamped between the clamp arm 22 and the clamp receiving piece 23, and the seat belt 24
24 withdrawals are blocked.

Even if the emergency lock mechanism operates before the clamp arm 22 swings, torque is generated in the electric motor 11 to rotate the reel 7 and the motor rotation shaft 12 in the A direction. Therefore, the clamp arm 22 swings in the B direction by this torque, and the seat belt 24 is strongly clamped between the clamp arm 22 and the clamp receiving piece 23, and as a result, the seat belt 24 can be prevented from being pulled out. It will be possible.

Further, when a large acceleration is generated due to a collision or the like, as shown in FIG. 6, the pendulum 39 is tilted and the locking claws 40 are engaged with the outer peripheral locking teeth 30a of the flywheel 30 to fly. Although the wheel 30 is locked, the pulling tension acts on the seat belt 24 due to the large acceleration described above, and the reel 7, the reel shaft 9 and the retainer 28 try to rotate in the B direction. Attempt to rotate in the B direction around 29b as a result overcomes the spring force of the compression coil spring 36 and moves in the C direction, and the locking claw 29e of the inertia mass 29 causes the locking teeth of the clutch body 27 to move.
The clutch main body 27 is also rotated in the B direction by engaging with 27d, and the rotation of the clutch main body 27 in the B direction causes the projection 33b of the pawl 33 engaged with the engaging hole 27c of the clutch main body 27 to swing in the A direction. The pawl 33 is moved, the tip claw 33c of the pawl 33 is engaged with the ratchet 25, and the reel 7 is locked so as not to rotate.

When such a large acceleration occurs and the emergency locking mechanism operates, the seat belt control device (not shown) causes the electric motor 11 to move the seat belt.
A current flows to rotate the motor 24 in the winding direction, and the motor casing 13 rotates with a torque in the direction opposite to the rotation direction A of the motor rotating shaft 12, and the clamp arm 22 is rotated as described above.
Swings in the B direction and seat belt 24 is clamped
Since it is sandwiched between 22 and the clamp receiving piece 23, the withdrawal of the seat belt 24 due to the tightening is also prevented.

In the embodiment shown in FIGS. 1 to 6, when a large pulling tension is applied to the seat belt 24 in an emergency, the tip claw 33c of the pawl 33 engages with the ratchet 25 and the emergency locking mechanism is provided. Is locked, but before and after this,
A torque that causes the seat belt 24 to be wound around the reel 7 is generated in the electric motor 11, and the clamp arm 22 is swung in the B direction due to the reaction force thereof. As shown in FIG. Since the seat belt 24 is sandwiched between the seat belt 24 and the clamp receiving piece 23 and the tension in the pulling direction applied to the seat belt 24 is borne, the seat belt 24 wound around the reel 7 is tightened. The withdrawal is blocked in advance, and the restraint performance of the seat belt 24 is extremely high.

When the electric current for winding the seat belt 24 around the reel 7 stops flowing to the electric motor 11, the torque for swinging the clamp arm 22 in the B direction disappears.
As shown in FIG. 3, the clamp arm 22 swings in the direction A by the spring force of the compression coil spring 20, and the seat belt 24 formed by the clamp arm 22 and the clamp receiving piece 23.
The seat belt 24 can be pulled out and the vehicle can be easily removed from the vehicle.

In the embodiment shown in FIGS. 1 to 6, the reaction force of the winding torque acting on the electric motor 11 is transmitted to the clamp receiving piece 23 via the link means 16, and the clamp receiving piece 23 is swung in the B direction. However, as shown in FIGS. 7 to 8, the upper end of the piston rod 43 of the hydraulic cylinder 42 having the compression coil spring is pivotally attached to the end of the motor arm 17 integrated with the motor casing 13. Connecting pipe with the hydraulic cylinder 42
The upper end of the piston rod 46 of the hydraulic cylinder 45 connected via 44 may be pivotally attached to the clamp arm 18 integrated with the clamp arm 22, and in such an embodiment, the torque in the B direction is applied to the motor casing 13 as well. When working, the oil in the hydraulic cylinder 42 is supplied to the hydraulic cylinder 45 via the connecting pipe 44, and the upward extension of the piston rod 46 causes the clamp arm 22 to move to the B position.
By swinging the seat belt 24 in the same direction, the seat belt 24 can be prevented from being pulled out similarly to the above-described embodiment.

In this embodiment, since the positional relationship between the hydraulic cylinder 42 and the hydraulic cylinder 45 can be freely set, the clamp arm 22 and the clamp receiving piece 23 can be arranged at a position apart from the electric motor 11.

Further, in the embodiment shown in FIGS. 1 to 6, a limit switch is arranged near the compression coil spring 20, the movable piece of the solenoid is connected to the clamp arm 18, and the motor casing 13 swings in the B direction. If you do, turn on the limit switch to operate the solenoid,
The clamp arm 22 may be configured to swing in the B direction.

[Brief description of drawings]

FIG. 1 is a schematic perspective view illustrating an embodiment of a vehicle seat belt withdrawal prevention device according to the present invention.

FIG. 2 is an exploded perspective view of FIG.

FIG. 3 is a side view showing the state before the operation of the drawer blocking device.

FIG. 4 is a side view illustrating a state after the operation of the drawer blocking device is illustrated.

FIG. 5 is a side view illustrating an operating state of the emergency locking mechanism according to the embodiment when the seat belt is pulled out with a large pulling tension.

FIG. 6 is a side view illustrating a state in which the emergency lock mechanism operates when a large acceleration occurs in the embodiment.

FIG. 7 is a side view illustrating the operation of the drawer blocking device according to another embodiment of the present invention.

FIG. 8 is a side view showing the state after the operation of the drawer blocking device in the embodiment of FIG. 7;

[Explanation of symbols]

1 ... Frame, 2 ... One side wall part, 3 ... Central side wall part, 4 ... Other side wall part, 5 ... Back wall part, 6 ... Bottom wall part, 7 ... Reel, 8 ... Bushing, 9 ... Reel shaft, 10 ... Bearing , 11 ... Electric motor, 12 ... Motor rotating shaft, 13 ... Motor casing, 14 ... Casing short cylindrical portion, 15 ... Bearing, 16 ... Link means,
17 ... Motor arm, 18 ... Clamp arm, 19 ... Link rod, 20
… Compression coil spring, 21… Clamping shaft, 22… Clamping arm, 23… Clamp receiving piece, 24… Seat belt, 25…
Ratchet, 26 ... tie plate, 27 ... Clutch body, 28
... Retainer, 29 ... Inertia mass, 30 ... Flywheel, 31 ... Friction locking plate, 32 ... Screw, 33 ... Paul, 34 ... Pin, 35 ... Clutch return spring, 36 ... Compression coil spring, 37 ... Lock starting mechanism, 38 ... Base piece, 39 ... Pendulum, 40 ... Locking claw, 41 ... Cover, 42 ... Hydraulic cylinder, 43 ...
Piston rod, 44 ... connecting pipe, 45 ... hydraulic cylinder, 46 ... piston rod.

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-4-314651 (JP, A) JP-A-5-254391 (JP, A) JP-A-5-254392 (JP, A) JP-A-5- 254393 (JP, A) JP-A-5-201310 (JP, A) Actual development 1-123759 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B60R 22/00-22 / 46

Claims (2)

(57) [Claims] 1. A reel connected to one end of a seat belt for restraining an occupant who is seated in a vehicle, and a seat belt which is located on the pull-out side of the seat belt from the reel and holds the seat belt to regulate the pull-out of the seat belt. And a shaft of the reel and a motor rotating shaft are connected to wind and pull out the seat belt and an electric motor casing rotates about the motor rotating shaft with respect to a frame that pivotally supports the reel shaft. A pivotally supported electric motor, a torque bearing means for bearing a winding torque acting on a casing of the electric motor when the seat belt is wound around the reel, and the clamp means operated by the operation of the torque bearing means. A seat belt withdrawal prevention device for a vehicle, comprising: 2. The torque bearing means and the driving means,
2. The vehicle seat belt withdrawal prevention device according to claim 1, wherein the device is a spring and a link means, respectively.