JP2000355265A - Seat belt device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate delay in occupant restraint (protection) due to winding and tightening of a webbing winding device. SOLUTION: This seat belt device consists of a webbing winding device (winding device) 100 with a clamp mechanism and a buckle pretensioner 600 arranged in a side part of a seat. When a vehicle collides, pulling in of a webbing 70 is done in the vicinity of a waist part of an occupant by the buckle pretensioner 600. When it is attempted to pull out the webbing 70 in the winding device 100 via a through tongue 508 due to the operation of the buckle pretensioner 600, the clamp mechanism operates to suppress reeling out by winding and tightening amount. Consequently, loosening of the webbing 70 is quickly removed to restrain (protect) the occupant on a seat 501.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seatbelt device, and more particularly to a seatbelt device with a pretensioner for restraining an occupant in a seat except for slack of a webbing (belt) in a collision to secure the occupant. Regarding improvement.

[0002]

2. Description of the Related Art A seat belt device is provided to reduce occupant injuries by suppressing the movement of an occupant in the event of a vehicle collision and to prevent a secondary collision with a vehicle interior structure (a steering wheel, a vehicle interior panel, etc.). Is used. Seat belt devices include:
A webbing take-up device (ELR) having a function of locking the webbing in order to prevent the webbing from being pulled out in the event of a collision, and a pre-winding device for taking up slack of the webbing and actively restraining the occupant to the seat in the event of a collision. A winding device with a tensioner (belt tensioning device) or the like is used.

[0003]

The safety of the occupant against a vehicle collision is required not only for a head-on collision of the vehicle but also for an offset collision. Safety measures against an offset collision are taken from the structural design of the vehicle body. First, the collision energy is absorbed by the crushable zone. However, in the offset collision, the impact absorption zone is narrower than in the case of the head-on collision, so that it is difficult to sufficiently absorb the impact. Therefore, the rigidity of the vehicle body is increased to minimize the deformation of the cabin (cabin) so as to secure a living space for the occupants.

As a result, in a vehicle body in which a required living space is ensured even in an offset collision, a vehicle body having a rigid structure tends to be changed from a vehicle body having a flexible structure suitable for absorbing shock. For this reason, the transmission of the deceleration applied to the occupant at the time of the collision becomes faster than in the case of a flexible-structured vehicle body that emphasizes a frontal collision, and the occupant starts to move forward (turn forward, move to the waist) earlier than in the case of a flexible-structured vehicle body. Also, the deceleration applied to the occupant increases.

In this case, the operation of the seat belt device is relatively delayed, and the degree of injury (damage) to the occupant at the time of a collision is increased.
Can also increase.

However, in a conventional seat belt device with an ELR, the bobbin around which the webbing is wound is locked at the time of a collision, so that the webbing is fed out by an amount corresponding to the tightening of the webbing, and the occupant is moved forward by that amount. there is a possibility. Here, "winding tightness" means that the webbing loosely wound around the bobbin is tightened (tightened) by the relative movement between the webbing and the bobbin.

Further, the seat belt device with the ELR having the clamp mechanism has a mechanism for holding the webbing in the event of a collision, so that the webbing can be prevented from being extended. However, the occupant cannot move forward due to the slack existing in the mounted webbing. Could be moved to

In the winding device with a pretensioner,
In the event of a collision, the pretensioner operates, rotates the bobbin in the winding direction, forcibly pulls the webbing into the winding device, restrains the occupant, but for tightening the webbing wound around the bobbin, The onset of the webbing is delayed by the tightening of the winding. The allowable range of this delay is extremely narrow in a vehicle body in which the propagation of a collision impact is fast.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a seat belt device that starts retracting webbing earlier to restrain (protect) an occupant when a vehicle collision is determined.

It is another object of the present invention to provide a seat belt device which can eliminate a delay in restraining (protecting) an occupant due to tightening of a webbing take-up device.

Another object of the present invention is to provide a seatbelt device suitable for a vehicle having a fast deceleration propagation such as a rigid structure vehicle in consideration of an offset collision.

Another object of the present invention is to provide a seat belt device capable of more sufficiently restraining the occupant's waist at the time of a vehicle collision.

[0013]

According to the present invention, there is provided a seat belt device for restraining an occupant to a vehicle seat by webbing so as to secure the occupant in a collision or the like. A buckle portion arranged near the waist of the occupant and engaged with the tongue plate having the webbing inserted therein, a buckle emergency retracting device (buckle pretensioner) for retracting the buckle portion, and detecting the collision of the vehicle with the buckle; A control unit that operates an emergency retraction device, a winding device (retractor) that has a clamp mechanism that winds the webbing and clamps the webbing to prevent the webbing from being pulled out when the vehicle is rapidly decelerated or suddenly pulled out, Is provided.

With this configuration, when the vehicle collides and the buckle emergency retraction device operates, the webbing is immediately retracted since the buckle pretensioner has no portion (bobbin) around which the webbing is wound. At the same time, the clamping mechanism of the winding device with the clamp is operated to directly clamp the webbing, thereby preventing the webbing from being pulled out from the winding device. As a result, the occupant is quickly restrained by the seat from the waist, and the degree of injury (damage) in an offset collision with a large impact can be reduced.

Preferably, the clamp mechanism operates in conjunction with a lock mechanism of the take-up device with the ELR, and the lock mechanism operates in response to sudden withdrawal of the webbing or detection of a large deceleration (or acceleration). I do.

Preferably, the buckle emergency retraction device is a gas-generating (eg, explosive) pretensioner. Thereby, a quick reaction and a large retraction force are obtained.

Preferably, the control unit includes a collision determination circuit composed of an acceleration (deceleration) sensor and an electric circuit (ECU) for determining a collision based on the output of the acceleration sensor. Perform collision determination with fewer errors.

Preferably, the winding device is in a state in which the webbing is prevented from being pulled out (clamp mechanism operation, ELR operation).
In the above, when a withdrawal load equal to or more than a predetermined value is applied to the webbing, the webbing can be pulled out and the impact on the chest of the occupant is reduced.

Preferably, the winding device includes an energy absorbing mechanism that allows the webbing to be pulled out at a portion where the load on the webbing exceeds a reference value.

Preferably, the control unit simultaneously activates the buckle emergency retracting device and a clamp mechanism of a winding device having a clamp mechanism.

[0021]

Embodiments of the present invention will be described below. First, the seat belt device of the present invention includes a buckle pretensioner and a winding device with a clamp mechanism. In the event of a collision, the buckle pretensioner starts retracting the occupant's waist immediately after actuation. In addition, the winding device with the clamp mechanism holds the webbing at the exit portion of the winding device and prevents the webbing from being pulled out from the winding device. Thereby, the slack of the webbing between the winding device and the buckle and the slack of the webbing between the buckle and the anchor bolt described later are simultaneously removed, and the waist and the upper body of the occupant are restrained by the seat. Since the slack of the webbing is removed at the waist, the waist is restrained quickly. The large deceleration acts to move the occupant forward, and when the load on the webbing exceeds a predetermined value, the energy absorbing mechanism (Energ
y Absorption) pulls the webbing forward, reducing damage to occupants.

FIG. 1 shows an embodiment of the seat belt device of the present invention. FIG. 1A is a front view of the seat belt device, and FIG. 1B is a side view thereof.

In the figure, a seat 501 is provided on a vehicle body 5.
02 is slidably mounted in the front-rear direction of the vehicle. A buckle pretensioner 600 is disposed at a lower left portion of the seat 501, and a webbing take-up device 100 is disposed at a lower right portion of the seat 501 (lower B pillar of the vehicle). An electric collision diagnosis circuit (EC) for activating the buckle pretensioner 600 is provided below the seat 501.
U) 510 is arranged. Electrical collision diagnosis circuit 510
Consists of a deceleration sensor (or acceleration sensor) and an electric circuit (computer system) for discriminating the output. The electrical diagnostic circuit removes noise from the deceleration output of the deceleration sensor by using a noise filter, for example.
Is converted into a speed signal by the integrating circuit of (1). This speed signal is converted into a displacement signal by a second integrating circuit, and the level of the displacement signal is compared with a comparison reference value by a level comparator. When the deceleration output exceeds a specified deceleration, an ignition signal is generated by the drive circuit, and this is transmitted to the buckle pretensioner 600.
Give to. As will be described later, a drive signal corresponding to an ignition signal may be generated in order to operate the electrically operated clamp mechanism of the winding device. In an emergency such as a vehicle collision, the buckle pretensioner 600 instantaneously retracts the webbing (seat belt) 70 that restrains the occupant 503 to the seat 501, loosens the webbing 70, and restrains the occupant 503 to the seat 501. Webbing take-up device 100 takes up and stores extra webbing 70. The webbing take-up device 100 includes a clamp mechanism to be described later, and suppresses the webbing 70 from being pulled out by directly sandwiching the webbing 70 at the time of sudden deceleration, thereby enhancing the slack removal effect of the buckle pretensioner 600.

One end of the webbing 70 is attached to a bobbin (not shown) of a webbing winding device (winding device) 100 and wound. The other end side of the webbing 70 is located above the shoulder of the occupant 503 and passes through a through portion (upper slip guide) 508 attached to the upper portion of the B pillar of the vehicle. An anchor plate (lower attachment portion) disposed below the B pillar. 509. Through part 50
A tongue plate 505 that is movable through the webbing 70 is provided between the webbing 70 and the anchor plate 509.

After the occupant 503 sits on the seat 501,
The webbing 70 is pulled out, the tongue plate 505 is inserted into the buckle 506, and the seat belt is fastened. Thereby, the webbing 70 reaches the right waist from the right shoulder opening of the occupant 503 through the left waist, and restrains the occupant 503 to the seat 501.

FIG. 2 shows a configuration example of the buckle pretensioner 600. The pretensioner 600 includes a case 601, a cylinder 602, a base 603, a gas generator 6
04, cap 605, pulley 608, wire 609,
It is constituted by a piston 612 and the like.

The case 601 has a storage section 601a for storing the gas generator 604 and a cylindrical gas combustion chamber 601b. The gas generator 604 generates an inflation gas by burning an explosive according to an ignition signal, for example. After inserting the gas generator 604 into the storage portion 601a of the case 601,
The cap 605 is screwed onto a screw thread 601f formed on the outer periphery of the opening 601e of the storage section 601a, and
Attach to The left end of the combustion chamber 601b formed in the case 601 and having a tubular shape in the lateral direction is open.
A thread groove is formed on the inner periphery of 01c. Further, a through hole 601d through which a cable 609 described later passes is opened at the center of the right side wall (bottom of the cylinder) of the combustion chamber 601b. The through hole 601d is provided with a step formed in a concentric circle, and a seal member 607 such as an O-ring for preventing gas leakage is provided at the step.

A thread is formed on the outer periphery of the right end of the cylindrical cylinder 602. This screw thread is screwed into the screw groove of the opening 601c of the combustion chamber 601b, and the cylinder 602 is connected to and attached to the combustion chamber 601b of the case 601. A piston 612 is arranged inside the cylinder 602. The piston 612 includes, from the right side, a cylindrical portion 612a that comes into contact with the cylinder, a truncated cone-shaped inclined surface portion 612b, and a cylindrical stopper portion 612c. An annular groove is formed in the outer periphery of the cylindrical portion 612a, and an O-ring (seal member) 612d is provided in the groove so as to be in close contact with the inner wall of the cylinder to prevent gas leakage. A plurality of steel balls 612e are arranged in a space between the cylinder inner wall and the inclined surface portion 612b. The ball 612e functions as a clutch that allows the piston to move only to the left in the drawing, as described later.

A base 60 is provided on the right side wall of the combustion chamber 601b.
3 is screwed by a bolt. A rotatable pulley 608 is provided on the base 603. The wire (wire rope) 609 includes a cylinder 602 and a piston 61
2. Arranged in a substantially J-shape through the combustion chamber 601b, the base 603, and the pulley 608, and the direction of movement is changed by the pulley 608. A buckle caulking ball 611 is attached to the upper end of the wire 609. The caulking ball 611 connects one end of the wire 609 to the buckle 506. Wire 6
The other end of 09 passes through the piston 612 and is exposed inside the cylinder. The caulking member 610 is attached to this exposed portion. An end portion of the caulking member 610 abuts on a left truncated cone-shaped inclined surface of the piston 612. Thus, when the piston moves to the left, the wire 609 also moves to the left, and the buckle 506 is retracted.

The operation of the buckle pretensioner configured as described above will be described.

First, when a sudden collision occurs due to a collision of a vehicle, this is detected by a deceleration (or acceleration) sensor. When the deceleration is given to the vehicle-mounted computer, the collision is determined, and an ignition signal is supplied to the gas generator 604. The gas generator 604 ignites the explosive, and combustion gas is instantaneously generated. The generation of gas is not limited to explosives, and various methods can be applied. Combustion chamber 601
The gas expanded at b increases the pressure and pushes the piston 612 to the left in the figure. The piston 612 includes a caulking member 6
Since 10 is locked, the wire 609 also moves to the left. The wire 609 is connected to the buckle 50 via the pulley 608.
6, the buckle 506, and thus the tongue plate 505, which engages the webbing 70, is pulled downward to loosen the webbing and restrain the occupant to the seat.

When the piston 612 moves to the left, the clutch mechanism provided on the piston 612
Since 2e moves to the right so as to go down the inclined surface of the piston, the ball freely rotates between the inclined surface and the inner wall of the cylinder, and does not hinder the movement of the piston 612. On the other hand, when the piston 612 moves to the right, the ball 612e
It is bitten between the inclined surface 612b and the inner wall of the cylinder while climbing up the cylinder 12b. The piston is locked by the wedge effect,
The return of the piston 612, that is, the rightward movement in the figure is prevented. As a result, it acts so that the restraint of the occupant to the seat is maintained.

Next, the webbing retractor 100 with a clamp mechanism will be described. Webbing take-up devices with a clamp mechanism are disclosed in, for example, JP-A-10-6922 and JP-A-7-285416.

In these devices, in the event of a vehicle emergency, an emergency lock mechanism that locks the rotation of the take-up shaft around which the webbing is wound in the webbing withdrawal direction by a lock means, and is movable in conjunction with the emergency lock mechanism. When the clamp member prevents the webbing from extending from the winding device by sandwiching the drawn-out portion of the webbing wound around the winding shaft of the winding device, and when a load equal to or more than a predetermined value is applied to the webbing. When the load acting on the webbing is greater than or equal to a predetermined value, the winding mechanism is interposed between the clamp mechanism configured to release the webbing sandwiching and the winding shaft and the locking means, and is wound around the shaft. And a torsion bar for rotating the take-up shaft in the webbing extension direction. The clamp mechanism and the torsion bar constitute an energy absorbing mechanism.

FIGS. 3 to 14 are explanatory views for explaining an example of a webbing retractor having a clamp mechanism.

3 and 4 are exploded perspective views of the winding device 100 with a clamp according to the present invention, and FIG. 5 is an enlarged perspective view of the latch plate 25 shown in FIG. 4, and FIGS.
FIG. 4 is a front vertical sectional view and a partially cutaway side view of the winding device with clamp 100 shown in FIGS. 3 and 4.

The winding device 100 with a clamp comprises a pair of opposed base side plates 1a, 1b and the base side plates 1a, 1b.
b, a take-up device base 1 made of a metal plate having a base back plate 1c for connecting the base plates b to each other; a latch plate 2 rotatably attached to the take-up device base 1 and at least one end thereof.
5 is a torsion bar 28 to which a torsion bar is attached.
An emergency lock mechanism 300 for preventing rotation of the latch plate 25 in the webbing pull-out direction in the event of a vehicle emergency; and a cylindrical winding on which the webbing 70 is wound and which is attached to the other end of the torsion bar 28 so as to rotate integrally therewith. A bobbin 2 serving as a take-up shaft, a rotation restricting means 30 disposed at a portion opposing the latch plate 25 and the bobbin 2 to prevent the bobbin 2 from rotating in a webbing extending direction beyond a predetermined angle,
A known take-up spring device 5 is connected to the other end of the torsion bar 28 and constantly urges the bobbin 2 in the webbing take-up direction (see FIG. 6).

The bobbin 2 constitutes an energy absorbing mechanism together with the torsion bar 28, has a substantially cylindrical shape obtained by combining an aluminum alloy or steel and a resin, and has a body around which the webbing 70 is wound. Is provided with a slit opening 2a that penetrates in the radial direction in order to insert and hold the end portion. At both ends of the bobbin 2 in the axial direction, a fitting hole 34 and a loose fitting hole 35 are formed to penetrate. Further, the take-up spring device 5 in which the fitting hole 34 is formed.
A sleeve 3 inserted into a shaft through hole of the base side plate 1a is mounted on an end of the bobbin 2 on the side.

Further, a recess formed at the end of the bobbin 2 on the side of the emergency lock mechanism 300 in which the loose fitting hole 35 is formed,
A shear pin 32 and a pivot pin 33 protrude, and together with a stopper 31 and an annular cam ring 20, constitute a rotation restricting means 30. The stopper 31 has the through hole 3
1b is pivotally supported by a pivot pin 33 passing therethrough. Then, the locking portion 31a on the swinging end side engages with the stopper engaging portion 29a (see FIG. 5) of the boss portion 29 protruding from the inner surface of the latch plate 25, so that the stopper 31 is The rotation of the bobbin 2 with respect to the latch plate 25 in the webbing extension direction at a predetermined angle or more can be prevented.

An engagement projection 31c protruding from the swinging end side of the stopper 31 is engaged with a cam groove 22 of the cam ring 20, which will be described later.
As a result, it is swung in the direction to engage with the stopper engaging portion 29a. A cam groove 22 having a bottomed groove along the inner peripheral edge thereof is engraved on the inner surface of the cam ring 20, and a C-shaped bottomed groove is formed on the outer surface along the circumferential direction. A groove 21 is engraved. Then, the cam ring 20
Are rotatably arranged around the boss 29.

The guide groove 21 is set so that the distance from the initial end 21A to the end 21B of the guide groove 21 is approximately one half of the outer peripheral distance of the cam ring 20.
The set distance of the guide groove 21 can be appropriately selected (see FIG. 12). On the inner surface of the latch plate 25 facing the cam ring 20 in which the guide groove 21 is engraved, a locking projection 26 slidable along the inner wall surface of the guide groove 21 as shown in FIG. It is protruding.

Therefore, the locking projection 26 is movable relative to the cam ring 20 over the entire area of the guide groove 21. That is, the cam ring 20 is approximately 1
It can rotate relative to 80 degrees. The shear pin 32 is fitted in a locking hole 27 formed in the boss 29 of the latch plate 25, and regulates the relative rotation of the latch plate 25 with respect to the bobbin 2. When a predetermined or more torsional force acts between the bobbin 2 and the latch plate 25, the shear pin 32 is sheared, and the bobbin 2 can be rotated relative to the latch plate 25.

At both ends in the axial direction of the torsion bar 28,
A prismatic portion 28a set to a size that can be press-fitted into the square hole 25b of the latch plate 25;
4 and a prismatic portion 28b set to a size that can be press-fitted into the square hole 3a of the sleeve 3. Both ends of the torsion bar 28 are rotatably supported by a shaft support 61a of a sensor cover 61 and a sleeve 3 inserted into a shaft through hole of the base side plate 1a, respectively, which will be described later. The sleeve 3 is supported by a ring-shaped bearing bush 55 inserted between the sleeve 3 and the base side plate 1a. The end of the torsion bar 28 on the base side plate 1b side is supported by a shaft support pin 36. Be pivoted. In the present embodiment, the prismatic portions 28a, 28b and the square holes 25b, 3
Although a and 34 have a hexagonal shape, they are not limited thereto.

Outside the latch plate 25, a latch cup 40 as a lock operating means for operating the emergency lock mechanism 300 in the event of a vehicle emergency is provided so as to be rotatable relative to the latch plate 25. That is, bobbin 2
Between the bobbin 2 and the latch plate 25 in a state where the webbing is prevented from being pulled out by the emergency lock mechanism 300, the energy absorbing mechanism 200 mainly including the torsion bar 28 is formed between the bobbin 2 and the latch plate 25. When a load (direction for rotating the bobbin 2) is applied to the torsion bar 28, the torsion bar 28 is twisted around its own axis to rotate the bobbin 2 under a predetermined torque. Because the emergency lock mechanism 300 prevents the latch plate 25 from rotating in the webbing withdrawal direction,
A predetermined amount of webbing can be withdrawn under a predetermined webbing tension, and collision energy acting on the occupant's body can be absorbed as deformation work.

As understood from FIG. 6, the torsion bar 28, the latch plate 25, the bobbin 2, the cam ring 2
In a state where the sleeve 0 and the sleeve 3 are assembled to the winding device base 1, the prismatic portions 28a and 28b at both axial ends of the torsion bar 28 are connected to the square holes 25b,
The bobbin 2 rotates integrally with the latch plate 25 in a normal use state because the bobbin 2 is press-fitted to each of 3a and 34. Note that the latch plate 25 may be configured integrally with the torsion bar 28 in advance.

The emergency locking mechanism 300 includes a locking means comprising a latch plate 25 and a pawl 11 for engaging the engaging teeth 25a to prevent the latch plate 25 from rotating in the webbing pulling-out direction (the direction of arrow X1 in FIG. 5). Having. Then, on one end side of the torsion bar 28,
Known locking operation means for operating the locking means in the event of a vehicle emergency is provided. The locking portion 11 a of the pawl 11 is engaged with the engagement teeth 25 a of the latch plate 25 in the event of a vehicle emergency.

The tension plate 9 having the through hole 9c inserted therein and the latch cup 40 having the internal teeth 40a are loosely fitted to a part of the torsion bar 28 protruding outward from the latch plate 25. The latch cup 40
The return spring 41 is mounted on the spring hanger 40b formed on the tension plate 9 and the spring hanger 9a formed on the tension plate 9, and a biasing force that rotates the latch cup 40 in the direction of arrow X2 is applied (see FIG. 7). ).

The torsion bar 28 located outside the latch cup 40 is provided with a lock member 51 and an inertia member 52 constituting the above-mentioned lock operating means, and tension is applied to the webbing 70 in an emergency such as a collision. When the bobbin 2 is subjected to a shocking rotational force in the direction of pulling out the webbing that is equal to or more than a predetermined value (direction of arrow X1), the latch cup 40 is rotated in the direction of arrow X1 against the urging force of the return spring 41.

The pole 11 is supported by the outside of the base side plate 1b via the pole pin 10 so as to be detachable from the latch plate 25. The pole pin 10 is provided with a through hole 45 and a long hole 46 formed in the opposing base side plates 1a and 1b.
And the outer end side shaft portion 10a is swingable about an engagement portion with the through hole 45.

The outer end side shaft portion 10 of the pole pin
A through hole 9b formed at the swinging end of the tension plate 9 is inserted into a. Therefore, the pole 11 can displace the swing rotation center along the elongated hole 46. The pole 11 is provided with a pole guide protrusion 11b, and the pole guide protrusion 11b is inserted into a pole guide hole 40c formed on the outer periphery of the latch cup 40.

Further, the base side plate 1b covering the emergency lock mechanism 300 comprising these lock means and lock operating means.
The sensor cover 61 is provided with a shaft support 34b at the center thereof for rotatably supporting the torsion bar 2 via a shaft support pin 36. The bottom surface of the shaft support 34b is a torsion bar. 2, and a positioning surface in the axial direction. A vehicle body acceleration sensing means 60 is provided below the base side plate 1b.

Above the inside of the winding device base 1, there is provided a clamp mechanism 400 for directly holding the webbing 70 to prevent the webbing from being pulled out.
The clamp mechanism 400 includes a lower plate 4 fixedly provided at a fixed position on the base back plate 1c of the winding device base 1.
A clamp member 6 having a large number of locking projections 6c pressed against the webbing 70; a clamp lever 7 for holding the clamp member 6 and moving the clamp member 6 in an emergency; The upper plate 12 and the guide plate 14, which are clamp regulating members for regulating the moving position of the clamp member 6 so that the clamp member 6 properly clamps the webbing 70 when moving, and the upper plate 12 is connected to the winding device base 1.
The upper stay 13 is a holding means fixed to the base side plates 1a and 1b.

The clamp member 6 has locking projections 6c arranged on a pressing surface pressed against the webbing 70, and has a shaft portion 6a supported by the clamp lever 7 and a guide plate 14 on the rear end side. And an engaging portion 6e guided by the guide portion 14a. The clamp lever 7 includes a pair of base side plates 1a,
It is supported so as to be able to swing around a shaft 17 provided between the shafts 1b, and a shaft portion 6a of the clamp member 6 is held at a tip portion 7a. The clamp lever 7 operates in conjunction with the emergency lock mechanism 300 described above. In an emergency where the emergency lock mechanism 300 prevents the bobbin 2 from rotating in the webbing pull-out direction, the tension plate 9 is used.
By swinging in the direction of arrow Y in FIG. 7 via the lever member 8 and the lever member 8, the clamp member 6 is pressed against the webbing 70 to prevent the webbing 70 from extending. The clamp lever 7 is normally urged in a direction opposite to the arrow Y by a return spring 15 disposed on the back surface 12d side of the upper plate 12 so that the clamp member 6 does not contact the webbing 70. I have.

The upper plate 12 is supported by a guide groove 71 formed in the base side plates 1a and 1b of the winding device base 1 so as to be movable in the pulling-out direction of the webbing 70. On the other hand, the upper stay 13 is formed into a predetermined shape by bending a metal plate, and is fixed to the base side plates 1a and 1b by screws.
3a, a plastic deformation plate portion 13b that is continuous with the side wall portion 13a and has a U-shaped curved vertical cross section, and a screw is formed on the upper plate 12 at one end of the plastic deformation plate portion 13b. And a plate supporting portion 13c to be stopped.

The plate portion 13b for plastic deformation is
When the load acting on the plate support portion 13c via the clamp member 6 and the upper plate 12 reaches a predetermined value due to an increase in the tension acting on the webbing, the plastic deformation is generated by the load in the webbing pull-out direction at that time. The shape, size, and material such as the radius of curvature of the U-shaped curved portion are selected.

Next, the operation of the winding device with clamp 100 will be described. First, during normal use, the emergency lock mechanism 300 is in an inactive state, and the winding device 1
Reference numeral 00 indicates that the webbing 70 can be wound by the urging force of the winding spring device 5 and the webbing 70
Can be pulled out freely. As shown in FIGS. 7 and 8, the clamp member 6 is kept separated from the webbing 70 by the spring force of the return spring 15 or the like.

However, in an emergency where a sudden deceleration occurs due to a vehicle collision or the like, the output of the acceleration sensor is used to control the ECU.
An ignition signal is provided from 510 to buckle pretensioner 600, and buckle pretensioner 600 operates.
The buckle 506 and the tongue plate 505 engaged with the buckle 506 are retracted, so that the slack of the webbing 70 inserted into the tongue plate 505 is removed and the webbing 70 is quickly pulled out of the winding device 100. . As a result, the emergency lock mechanism 300 for restricting the rotation of the bobbin 2 operates, and the locking portion 1 of the pawl 11
1a is engaged with the engaging teeth 25a of the latch plate 25 to prevent the latch plate 25 from rotating in the webbing pull-out direction. In this state, when tension is further applied to the webbing 70 in the pull-out direction, the tension plate 9 through which the pole pin 10 supporting the pole 11 penetrates,
It starts to rotate in the X1 direction in FIG. By this rotation, the lever member 8 engaged with the tension plate 9 is moved in the Y direction, and the clamp lever 7 similarly engaged with the projection 8a of the lever member 8 through the hole 7c is also moved around the shaft 17 in the arrow Y direction. And pushes out the clamp member 6 along the sliding contact surface 12a of the upper plate 12, and as shown in FIG.
The clamping mechanism 400 that presses the locking projections 6c of the clamp member 6 against the webbing 70 to pinch the webbing 70 and that prevents the webbing 70 from extending due to tightening is activated.

As a result, since the webbing is prevented from being pulled out by the tightening of the webbing, and the buckle 506 is retracted by the operation of the buckle pretensioner 600, the slack of the webbing 70 is removed, and the occupant is restrained by the seat.

Next, the occupant starts to move forward, and the moving load acts to pull out the webbing 70. Webbing withdrawal (extension) by the above webbing clamp
, The tension acting on the webbing 70 gradually increases, and when the load acting on the upper stay 13 reaches the above-described predetermined value, the plastic deformation plate portion 13b Bending (plastic deformation) occurs in the vicinity of the U-shaped curved portion of (a), the plate supporting portion 13c can be moved in the webbing extending direction.

The deformed position of the plastic deformation plate portion 13b near the curved portion is displaced on the plastic deformation plate portion 13b in accordance with the movement of the plate support portion 13c, and as a result, as shown in FIG. The plate support portion 13b is allowed to move in the webbing extension direction in a manner as if the curved portion gradually moved. The movement of the plate supporting portion 13b in the webbing extending direction is the movement of the upper plate 12 and the clamp member 6 in the webbing extending direction,
Thereby, the extension of the webbing 70 is realized,
The kinetic energy acting on the webbing 70 is absorbed by the plastic deformation plate portion 13b in accordance with the amount of extension, and the impact or the like acting on the occupant's body from the webbing is reduced.

Then, as shown in FIG. 10, when the plastic deformation of the upper stay 13 is completed, the locking projection 6c of the clamp member 6 is connected to the webbing 70 by the belt relief recess 4a provided on the lower plate 4. Is disengaged. After the webbing is released from being clamped by the clamp member 6, the webbing 7 from the winding device is released.
0 starts to extend, and a tension acts on the bobbin 2 in the webbing withdrawal direction. Then, the bobbin 2 to which one end of the webbing 70 is locked starts to rotate, and the latch plate 2
When a load equal to or more than 5 is applied, the torsion bar 28 whose one end is connected to the rotation-locked latch plate 25 is twisted around its own axis after the shear pin 32 is sheared. Bobbin 2 under given torque
Is rotated, so that the torsion bar 2 can further absorb kinetic energy by being twisted around its own axis.
More desirably, for example, by setting the strength so that the webbing tension during torsional deformation is kept substantially constant,
More effective kinetic energy can be consumed during the torsional deformation process.

Accordingly, the tension acting on the webbing 70 in the winding device with clamp 100 exhibits a smooth fluctuation characteristic. That is, the upper plate 1
By repeating the effective absorption of kinetic energy stepwise and over a longer period of time by the plastic deformation of the torsion bar 2 and the plastic deformation of the torsion bar 2, a greater amount of exercise can be performed without increasing the damage to the occupant's body. Energy can be quickly absorbed by the seat belt retractor, and the increase or decrease in the tension acting on the webbing 70 after the webbing is clamped can be suppressed gently, and the fluctuation range of the tension can be reduced. It is possible to effectively and greatly reduce the impact acting on the occupant from the webbing 70 at the time or the like.

Further, since the energy absorption after the webbing is released by the clamp member 6 is released by the torsion bar 2 twisting around the axis, the amount of movement of the clamp member 6 until the torsion bar 2 starts torsional deformation. (The amount of movement in the webbing extension direction while plastically deforming the plastic deformation plate portion 13b) can be reduced, and the winding device base 1 can be downsized accordingly. Also, torsion bar 2
Is connected to the bobbin 2 via the shear pin 32, so that the timing at which the torsion bar 2 starts torsional deformation can be advanced.

Further, since the rotation of the bobbin 2 in the webbing extending direction beyond a predetermined angle is prevented by the rotation restricting means 30, a load that twists the torsion bar 2 more than necessary in a vehicle emergency or the like is applied. In this case, the amount of extension of the webbing 70 is regulated to an appropriate amount, so that the safety of the winding device is improved.

Here, the operation of the rotation restricting means 30 will be described with reference to FIGS.

As shown in FIG. 12, in the initial position after the webbing is released, the shearing pin 32 protruding from the bobbin 2 is fitted into the locking hole 27 formed in the boss 29 of the latch plate 25. The rotation of the bobbin 2 relative to the latch plate 25 is restricted. The locking projection 26 of the latch plate 25 is located at the initial end 21A of the guide groove 21.

When a predetermined load or more is applied between the bobbin 2 and the latch plate 25 and the shear pin 32 is sheared, the torsion bar 2 is torsionally deformed, and the length (1 2 rotation), the bobbin 2 is rotated relative to the latch plate 25 in the direction of arrow X1 in the figure, and the locking projection 26 slides in the guide groove 21 to relatively move in the direction of arrow X2. Moving. Therefore, as shown in FIG.
Reach B.

When the bobbin 2 is further rotated in the direction of arrow X1 in the figure, the cam ring 20 urged by pressing the end portion 21B by the locking projection 26 rotates in the direction of arrow X2 together with the locking projection 26. . When the cam ring 20 rotates relative to the bobbin 2 in the direction of arrow X2, the stopper 31 in which the engagement protrusion 31c is engaged with the cam groove 22 of the cam ring 20 is locked as shown in FIG. Part 3
1a is swung in the direction of engagement with the stopper engaging portion 29a of the boss portion 29.

When the stopper 31 pivotally supported by the pivot pin 33 protruding from the bobbin 2 is engaged with the stopper engaging portion 29a, the bobbin 2 is moved beyond the latch plate 25 by a predetermined angle in the webbing extending direction. Rotation is prevented. That is, the rotation restricting means 30 includes the guide groove 2
The rotation restricting angle of the bobbin 2 in the webbing extension direction is set in accordance with the length of the bobbin 2, so that, for example, the type of the vehicle and the running performance of an ordinary passenger car, a large vehicle, etc. It is easy to set a proper rotation restriction angle, and more accurate vehicle safety can be ensured.

The configurations of the winding shaft and the torsion bar in the above embodiment are not limited to those of the embodiment, and various changes can be made.

Further, the clamp mechanism is not limited to the configuration of the winding device with clamp of the above embodiment, and the shape and number of components such as the upper plate 12 and the upper stay 13 can be variously changed. Of course, for example, the tensile load of the webbing when the clamp mechanism is released as described above and the tensile load after the release,
It can be set as appropriate by changing the shape of the plastic deformation plate portion 13b of the upper stay 13 or changing the rigidity of the plastic deformation portion. Further, the present invention is also effective for a clamp mechanism using a rotary holding member in place of the wedge-shaped clamp member. The clamp release mechanism is not limited to the belt relief concave portion 4a provided on the lower plate 4, but may be a known clamp release mechanism. Can be used.

An electric control circuit (ECU) for determining a collision based on the output of a deceleration sensor is a clamp mechanism in which a clamp member is moved by an urging force of a solenoid.
The control by 510 may be adopted. In this case,
Both the buckle pretensioner 600 and the clamp mechanism 400 of the webbing take-up device 100 can be forcibly operated substantially simultaneously, and a responsive operation can be expected. By setting the supply timing of the operation signal in consideration of the response characteristics of both devices, it is also possible to accurately synchronize the operations of both devices.

Further, the present invention is not limited to the configuration of the emergency lock mechanism 300 as in the above embodiment, but can be applied to a winding device with a clamp having an emergency lock mechanism provided with other lock means and lock operating means. It is.

As described above, according to the embodiment of the present invention, when the vehicle collides, a rapid deceleration occurs, and the buckle pretensioner 600 operates. This allows
The buckle 506 and the tongue plate 505 engaged with the buckle 506 are retracted. Therefore, the webbing 70 inserted into the tongue plate 505 is retracted, and the slack of the webbing 70 is removed. Further, the webbing 70 is suddenly tightened by the operation of the acceleration sensing device 60 or the buckle pretensioner 600, that is, the emergency locking mechanism 300 is also activated by suddenly pulling out the webbing 70 from the webbing winding device 100. When the emergency lock mechanism 300 operates, the clamp member 6 moves and bites the webbing 70. As a result, the webbing 70 is directly pinched, and the tightness of the webbing 70 is prevented from being pulled out. In this way, pulling out of the webbing from the webbing winding device 100 is prevented, and
By retracting the buckle 506, the slack of the webbing is removed, and the occupant is restrained (protected) by the seat 501 (FIG. 9).

Next, when a sudden deceleration is applied to the occupant, a force for moving the occupant forward acts on the webbing 70. With the clamp member 6 biting into the webbing 70, the webbing 7 is moved by the force to move the occupant forward.
When a large tension is applied to 0, the plastic deformation plate 13b is deformed, and the clamp member 6 moves in the direction of the arrow along with the webbing 70 (FIG. 10).

When the teeth of the clamp member 6 move to the cutouts of the lower plate 4, the teeth of the clamp member 6 are broken by the tension of the webbing 70. Then, the tension of the webbing 70 is transmitted to the bobbin 2 side. When the shaft 28 is twisted with a predetermined load, the webbing 70 extends (FIG. 11).

The above-described clamping operation improves the initial restraint of the occupant, and allows the webbing 70 to extend while maintaining a predetermined load. By allowing the webbing 70 to be pulled out, the belt load does not increase above a certain level, so that the chest injury value of the occupant restrained by the webbing 70 can be reduced.

The winding device 100 with a clamp employs a method in which the webbing 70 is directly clamped near the exit of the winding device and the amount of extension of the webbing 70 is almost zero, so that the webbing 70 is assembled with the buckle pretensioner. In this case, the "tightening time" specific to the pretensioner when installed on the retractor side can be ignored. Although the stroke required until the clamp mechanism 400 operates and completely clamps the webbing 70 exists slightly, the clamp mechanism 400 has a low load (100 N).
The lock is completed immediately after the operation of the buckle pretensioner 600 is started.

According to the embodiment described above, there are the following advantages as compared with other conceivable configurations.

(1) Comparison between a winding device with a pretensioner and a combination of a buckle pretensioner Two gas generators, one for the winding device and one for the buckle, are required per seat. On the other hand, the system of the present invention requires only one buckle, so that the existing ECU system can be used. The number of expensive gas generators does not increase. Since the winding device with the clamp mechanism is cheaper than the winding device with the pretensioner mechanism, the cost of the device can be reduced.

As described above, since only one gas generator is required, the pollution of the atmosphere in the vehicle interior due to the gas ejected from the gas generator in the event of an accident is reduced.

Since the weight of the entire seatbelt device is reduced, the weight can be reduced.

(2) Comparison between the combination of an emergency lock type wind-up device (ELR) and a buckle pretensioner In the case of a general wind-up device, the above-mentioned tightening amount has a great effect, and the belt is not affected by the buckle retraction. The tightening amount is pulled out from the winding shaft (bobbin). Load (belt tension) at which the clamp starts clamping the webbing is 100N
On the other hand, in the case of the general winding device, a belt tension of about 2000 N is required until the tightening amount is removed.

Therefore, it is considered difficult to generate a tension equivalent to 2000 N by the buckle pretensioner to remove all the tightening.

[0085]

As described above, the seat belt device according to the present invention has a quick response to the retraction of the webbing, and can quickly restrain the occupant. It is possible to avoid a relative delay in the operation of the seat belt device when the vehicle is used for a vehicle having a vehicle body with a fast deceleration propagation at the time of a collision. It is preferable because it is easy to comprehensively secure occupant safety in combination with a vehicle body, an airbag, or the like that considers an offset collision.

Further, since the slack of the webbing at the occupant's waist is quickly removed, it is effective to prevent the waist from moving when the deceleration is large.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory views illustrating the configuration of a seatbelt device according to the present invention. FIG. 1A is a front view, and FIG.
Is a side view.

FIG. 2 is an explanatory diagram illustrating a configuration of a buckle pretensioner in a partial cross section.

FIG. 3 is a part of an exploded perspective view of the winding device with a clamp according to the present invention.

FIG. 4 is an exploded perspective view of a remaining portion of the winding device with a clamp shown in FIG. 3;

FIG. 5 is an enlarged perspective view of a latch plate 25 shown in FIG. 4;

FIG. 6 is a front vertical sectional view of the winding device with a clamp shown in FIGS. 3 and 4;

FIG. 7 is a partially cutaway side view of the winding device with a clamp shown in FIGS. 3 and 4;

FIG. 8 is an enlarged view of a main part for explaining the operation of the clamp mechanism shown in FIG. 3;

FIG. 9 is an enlarged view of a main part for explaining the operation of the clamp mechanism shown in FIG. 3;

FIG. 10 is an enlarged view of a main part for explaining the operation of the clamp mechanism shown in FIG. 3;

FIG. 11 is an enlarged view of a main part for explaining the operation of the clamp mechanism shown in FIG. 3;

FIG. 12 is a sectional view of an essential part for describing the operation of the rotation restricting means shown in FIG. 4;

FIG. 13 is a sectional view of an essential part for describing the operation of the rotation regulating means shown in FIG. 4;

FIG. 14 is a sectional view of an essential part for describing an operation of the rotation regulating means shown in FIG. 4;

[Description of Signs] 60 Mechanical acceleration detection device 70 Webbing 100 Webbing take-up device (retractor) with clamp mechanism 501 Seat 502 Body 510 Collision diagnosis circuit (ECU) 600 Buckle pretensioner 400 Clamp mechanism 300 Emergency lock mechanism (ELR)

Claims (1)

[Claims] 1. A seat belt device for restraining an occupant by a webbing on a seat of a vehicle to secure the occupant in the event of a collision or the like, wherein the tongue plate is disposed near a waist of the occupant and has a webbing inserted therethrough. A buckle portion that engages with the buckle portion, a buckle emergency retraction device that retracts the buckle portion, a control unit that detects the collision of the vehicle and activates the buckle emergency retraction device, and winds up the webbing and rapidly decelerates the vehicle. Or a winding device having a clamp mechanism for holding the webbing and preventing the webbing when the webbing is suddenly pulled out.