JPH03295740A - Seat belt stretching device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention A0 Object of the Invention (1) Industrial Application Field The present invention relates to a seat belt tensioning device mainly used in automobiles, and in particular, to a seat belt tensioning device for tightening a buckle to which a seat belt is connected. A driving member is guided by the frame so as to be movable from a relaxed position in a tensioning direction and is connected to a support member via a cable, and a driving force generating device that provides driving force to the driving member is used to tow the cable in an emergency. Regarding improvements to the frame.

(2) Conventional seat belt tensioning devices include, for example, Japanese Patent Application Laid-open No. 1-111
This is already known as disclosed in Japanese Patent No. 9455.

(3) Problems to be Solved by the Invention In the seat belt tensioning device disclosed in the above publication, the buckle supporting member, the driving member, and the driving force generating device are
Since they are arranged in a letter-shaped relationship, the frame that supports them also forms an L-shape, so the frame has a large amount of horizontal overhang, and when installed on the floorboard inside the vehicle,
There is a problem that it easily interferes with other objects.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a compact seat belt tensioning device with a small amount of horizontal overhang of the frame.

B0 Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a frame with a sheath-like part with an open upper end that guides a support member, and a sheath-like part with an open upper end that guides a support member, and It is composed of a box-shaped part that overhangs and an inverted letter shape,
A driving member and a driving force generating device are disposed in the box-shaped portion so as to cross the axis of the sheath-shaped portion.

In addition, the "route" in the present invention refers to wires, cables,
A generic term for non-stretchable and flexible items such as belts and lobes. Further, the angle formed by the sheath-like part and the box-like part of the frame is determined as appropriate depending on the mounting position of the frame, the direction of the buckle, and the like.

(2) Effect According to the above structure, the drive member and the drive force generating device can be compactly housed in the box-shaped portion that projects approximately evenly forward and backward from the lower end of the sheath-like frame in the inverted-shape frame. The amount of overhang of the shaped portion in each direction can be halved compared to the conventional L-shaped frame.

(3) Examples Embodiments of the present invention will be described below with reference to the drawings.

1 to 7 show a first embodiment in which the present invention is applied to a seat belt tensioning device for an automobile. In the description, the terms "front and rear" and "left and right" refer to the front and rear directions and the left and right directions of the vehicle in which the present device is installed.

First, in FIGS. 1 and 3, a buckle 1 for connecting a seatbelt connection fitting (not shown) is fixed to the upper end of a flexible support rod 2 serving as a support member.

The support rod 2 is a metal cable covered with a synthetic resin tube, and the support plate 1-
2a is fixed. This support plate 2a is inserted into the frame 3 so as to be movable up and down, and when the support plate 2a is lowered, it tensions the seat belt connected to the buckle 1.

The frame 3 includes a sheath-like part 3a with an entrance 4 at its upper end, and a flat box-like part 3b extending forward and backward from the lower end of this sheath-like part 3a.
The box-like part 3b has ears 5, 5 protruding from both front and rear ends, which are fixed to anchors (not shown) provided on the floorboard or seat of the passenger compartment with bolts 6.6. be done. This frame 3 is covered with a cover 7 made of synthetic resin.

The support plate 2a of the support rod 2 is accommodated in the sheath 3a. Further, the support rod 2 has an enlarged portion 2 directly above the support plate 2a.
b, and this enlarged part 2b is provided with an entrance 4 of the sheath-like part 3a.
Lightly press-fitted into the This light press-fit keeps the buckle 1 at its upper limit, and as long as it is not subjected to a downward load exceeding a predetermined value,
It is designed to maintain its position.

In order to guide the lifting and lowering of the support plate 2a, a guide pin 8 protruding from one side of the support plate 2a is connected to the sheath-shaped portion 3a.
It is slidably engaged with a vertically long guide groove 9 formed on one side wall of the holder.

Inside the box-shaped part 3b of the frame 3, there are a pair of drive pulleys 11, 12, which are driving members that can pull the support plate 2a downward via wires 10, which are cables, and a pair of drive pulleys 11. A driving force generating device 13 that provides driving force to these drive pulleys 11 and 12 is housed.

The driving force generation device 13 includes a force storage spring 14 disposed in the center of the box-shaped portion 3b and with both ends facing forward and backward, and this force storage spring 1
The drive pulley 11.12 is supported by a shaft 17.18 on these brackets 15.16.

The brackets 15 and 16 are movable in the longitudinal direction of the vehicle together with the corresponding drive pulleys 11 and 12, and in order to guide the movement, the brackets 15 and 16 are perforated in the left and right side walls of the box-shaped portion 3b. A guide groove 19 extending in the longitudinal direction of
, 20 are slidably engaged with protrusions 21 and 22 protruding from both left and right side surfaces of the brackets 15 and 16 and shafts 17 and 18 of the drive pulleys 11 and 12, respectively.

A pair of guide pulleys 23° 24 adjacent to each other in the front and rear directions directly above the force storage spring 14 are pivotally supported on the left and right side walls of the box-shaped portion 3b, and a loop-shaped pulley is connected to the support plate 2a via the guide pin 8. The wire 10 is passed to the drive boots IJII and 12 via guide pulleys 23 and 24.

That is, two wires 10 are stacked and descend from the support plate 2a, are spread back and forth by the guide pulleys 23, 24, and go around the drive pulleys 11, 12 to form a loop.

As shown in FIGS. 3 to 5, two pairs of wire 10° guide pulleys 23, 24 and drive pulleys 11, 12 are provided on the left and right sides, but one set may be used as long as the wire 10 has sufficient strength.

In Figs. 2 to 5, the brackets 15 and 16 are equipped with a mechanism that locks both brackets 15 and 16 in a state in which the force storage spring 14 is compressed during normal times, and locks the brackets 15 and 16 when a deceleration of the vehicle exceeding a predetermined value is detected. A sensor 25 is connected to release the .

This sensor 25 is connected to the box-shaped part 3b via a pivot 26.27.
A pair of front and rear bell cranks 28.2 supported on one side wall of the
9 and one pendulum 31 supported via a pivot 30 on the outer wall of the box-shaped portion 3b. bell crank 28.2
9 is a first arm 2 extending downward from each pivot 26, 27;
8a, 29a, and second arms 28b, 29b extending diagonally upward from the pivot 26.27. First arm 28a.

29a are connected to the shafts 17.18 of the drive boots 1711 and 12 through elongated holes 32 and 33 provided therein, respectively, and the distal ends of the second arms 28b and 29b are connected to the box-shaped portion 3.
It is placed outside the box-shaped part 3b through window holes 34 and 35 in one side wall of the box part 3b. The interlocking pin 36 fixed to the tip of the second arm 28a at the front is slidably engaged with the elongated hole 37 of the second arm 28b at the rear.
．． 29 are interlocked and connected to each other. A roller 38 is attached to one end of the interlocking bin 36.

The pendulum 31 is supported by the pivot 30 so as to be able to swing back and forth in an inverted state. An L-shaped engagement surface 39 capable of supporting the roller 38 is formed at the upper end of the pendulum 31, and in a state in which the roller 38 is supported, the pendulum 31 is only allowed to swing forward. It has become. The horizontal portion of the L-shaped retaining surface 39 is an arcuate surface centered on the pivot 30.

When the roller 38 is supported on the engagement surface 39, the front and rear brackets 15, 16 come closest to each other to hold the force storage spring 14 in a compressed state, that is, a force storage state.

Also, the pendulum 31 is moved backward by the return spring 40, that is, the roller 3
8, and swings forward only when the vehicle experiences deceleration of a certain value or more due to sudden braking, collision, etc.

In FIG. 3, a one-way movement prevention device 41 is provided between the support plate 2a and the sheath-shaped portion 3a, which allows the support plate 2a to descend but prevents it from rising. This device 4
1 is a support plate) 2a, and a large number of locking teeth 43, 43, . and a spring 44 that urges the swing claw 42 in the direction of engagement with these locking teeth.

The locking teeth 43, 43, . . . are formed into a sawtooth shape with the tooth tips facing downward by partially cutting and raising the side wall of the sheath-shaped portion 3a. Therefore, when the swinging pawl 42 comes into contact with the tip of each locking tooth 43, the support plate 2a is prevented from rising, and as the swinging pawl 42 slides on the slope of each locking tooth 43, the support plate 2a is lowered. is allowed.

In FIG. 1, reference numeral 45 is a stopper for regulating the lower limit of the support plate 2a, and is formed by cutting and raising from the side wall of the frame 3.

Next, the operation of this embodiment will be explained.

FIG. 1 shows the normal state in which the support rod 2 of the buckle 1 has been pulled up to its upper limit. In this state, the support rod 2 has its enlarged portion 2b as the narrowed entrance of the sheath-like portion 3a as described above. 4
It is held by being lightly press-fitted into the Also the second arm 28
b, 29b so that the bell crank 28.29 is facing upward.
By rotating the roller 38 of the interlocking bin 36 to support the engaging surface 39 of the pendulum 31, the force storage spring 14 is maintained in the force storage state.

Therefore, even when the passenger inserts and connects the seatbelt connecting fitting pulled out from the retractor into the buckle 1 in order to put on the seatbelt when driving the vehicle, the buckle 1 remains at the upper limit position.

While driving a vehicle, if the vehicle decelerates above a certain value due to sudden braking or a collision, as shown in Figure 6,
The pendulum 31 swings forward against the force of the return spring 40, releasing the roller 38 from the engagement surface 39.

As a result, as shown in FIG. 7, the front and rear brackets 15, 16 move away from each other along with the drive pulleys 11, 12 due to the elastic force of the force storage spring 14, and the loop portion of the wire 10 is moved away from each other. As it unfolds, the wire 10 is pulled at twice the speed of movement of each drive pulley 11, 12, rapidly drawing the support rod 2 of the buckle 1 into the sheath 3a.

At the same time, the retractor becomes locked by a known action and prevents the seat belt from being pulled out, which applies tension to the seat belt, stretches the belt itself, and removes slack in the belt due to tightening by the tractor. Seat belts immediately exert a strong restraining force on occupants.

On the other hand, for bell crank 28.29, drive pulley 1
In conjunction with the movement of 1.12, the first arms 28a, 29a
are rotated in the direction of separation by the shafts 17 and 18, and therefore the second arms 28b and 29b are rotated downward so as to increase the weight of each other, and the interlocking pin 36 slides in the elongated hole 37.
The bell cranks 28, 29 do not impede the movement of the drive pulley 11, 12 in any way.

Also, when the support plate 2a is lowered, the one-way movement prevention device f
At f141, the swing claw 42 slides down the slope of each locking tooth 43 and descends together with the support plate 2a, but then when the buckle 1 is about to be pulled up due to the forward movement load of the occupant being applied to the seat belt, Swing claw 42
At that time, the locking teeth 43 engage with the tips of the opposing locking teeth 43 to restrain the buckle 1 from being pulled up, thereby maintaining the tensioned state of the seatbelt.

To pull up the buckle 1 to its upper limit again, remove the cover 7 from the frame 3, use a suitable tool such as a screwdriver to disengage the swing claws 42 from the locking teeth 43, 43, etc., and in this state, tighten the buckle. 1 strongly, the ampulla 2
b is inserted into the entrance 4 of the sheath-shaped part 3a. By pulling up the buckle 1 in this way, the wire 10 is moved to the support plate 2a.
Since the drive boots 1711 and 12, together with the brackets 15 and 16, are pulled upward by the bracket 15, 16 and are pulled toward each other while squeezing the loop portion, the force storage spring 14 can be compressed again.

Then, when the two drive boos Ull, 12 approach each other, the second arms 28b, 29b of both bell cranks 28, 29 rotate upward, and the roller 38 reaches its initial raised position (then the pendulum 31 returns to its original position). Since the force of the spring 40 swings backward and brings the engagement surface 39 to the supporting position of the roller 38, the force storage spring 14
The bell crank 28.29 will now be locked when the power is stored.

By the way, in such a seat belt tensioning device,
The support rod 2 can be retracted into the sheath-like part 3a of the inverted letter-shaped frame 3, and the drive pulley 11 is installed in the box-like part 3b of the frame 3.
．． 12 and the driving force generating device 13 are arranged so as to cross the axis of the sheath-like part 3a, so that the box-like part 3b from the sheath-like part 3a
The amount of front and rear overhang of the frame 3 can be reduced by half compared to a conventional L-shaped frame, and the frame 3 can be made more compact.

In addition, the inverted T-shaped frame 3 is supported by anchors on the vehicle body at two points, the ears 5.5 at both ends of the box-shaped portion 3b. The lifting load applied from the support rod 2 to the sheath-shaped portion 3a of the frame 3 is approximately evenly distributed to the two points, thereby suppressing deformation of the reframe 3 as much as possible.

8 and 8A show a second embodiment of the present invention, in which explosives are used as the driving force source of the driving force generating device 13. FIG. That is, this driving force generating device 13 includes a cylinder 46 fixed to the center of the box-shaped portion 3b of the frame 3 with both ends open in the front and rear, and a front and rear pair slidably fitted in the cylinder 46. pistons 47, 48, and drive pulleys 11.
Brackets 15, 16 that pivotally support 12 are fixed.

Both pistons 47,48 define an expansion chamber 49 between them. This expansion chamber 49 communicates with an explosive chamber 51 in a cylindrical portion 50 protruding from an example of the cylinder 46 through a through hole 52 . A filament 55 for igniting the gunpowder 54 loaded in the gunpowder chamber 51 is attached to a stopper 53 that closes the open end of the cylindrical part 50. It is designed to be energized by the signal it outputs when it senses.

The rest of the structure is substantially the same as that of the previous embodiment, and in the drawings, parts corresponding to those of the previous embodiment are given the same reference numerals.

Therefore, the filament 5 is activated by the output signal of the G sensor 56.
5 is energized and the gunpowder 51 is detonated, the generated gas blows out from the through hole 52 and increases the pressure in the fat expansion chamber 49, so the pistons 47 and 48 move away from each other and drive the drive pulleys 11 and 12. Extrude each back and forth, wire 1
0, the support rod 2 can be pulled downward to apply tension to the seat belt. In this case, the retraction speed of the support rod 2 is twice the moving speed of each piston 47, 48.

FIG. 9 shows a third embodiment of the present invention, in which an end wire is used instead of the loop wire in the first embodiment of FIG.
0 is used. That is, one end of the wire 10 is connected to the support plate 2a, and the other end is fixed to the locking part 57 of the box-shaped part 3b below the driving force generating device 13. In this embodiment, a guide pulley 2 that regulates the movement path of the wire 10 is used.
3 and the drive pulley 11 are sufficient, and the driving force generating device 13 is compressed between one bracket 15 and a support plate 58 fixed to the box-shaped portion 3b. The other configurations are substantially the same as the first embodiment.

FIG. 10 shows a fourth embodiment of the present invention, in which an explosive type driving force generating device 13 is used in place of the spring type driving force generating device 13 in the third embodiment shown in FIG. This driving force generating device 13 includes a bottomed cylinder 46 fixed to the box-shaped portion 3b, and a piston 47 that fits into the cylinder 46 and defines a powder chamber 51 between it and the bottom wall. A bracket 15 that pivotally supports the drive boob IJ 11 is fixed to this piston 47. Since the other configuration of the driving force generating device 13 is the same as that shown in FIG. 8, the same reference numerals are given to the parts corresponding to those in FIG. 8 in the figure.

C0 Effects of the Invention As described above, according to the present invention, the frame is formed into an inverted T-shape by a sheath-like part with an open upper end that guides the support member, and a box-like part that extends forward and backward from the lower end of this sheath-like part. The drive member and the driving force generating device are disposed in the box-shaped part so as to cross the axis of the sheath-shaped part, so that the box-shaped part extends approximately evenly forward and backward from the lower end of the sheath-shaped part of the frame. The driving member and the driving force generating device can be housed in a compact manner. Therefore, the frame can be configured to be compact with a small amount of overhang of the box-shaped portion, and interference with the other frame can be easily avoided when installed on the floorboard in the vehicle interior.

[Brief explanation of the drawing]

1 to 7 show a first embodiment of the present invention, in which FIG. 1 is a vertical sectional side view of an automobile seat belt tensioning device (cross-sectional view taken along line I-1 in FIG. 3), and FIG. is ■−■ in Figure 3.
The line sectional views, Figures 3 and 4, are the lines ■-■ and I in Figure 2.
5 is an exploded perspective view of the main parts, FIGS. 6 and 7 are explanatory diagrams of operation, and FIG. 8 is a vertical sectional side view showing the main parts of the second embodiment of the present invention, FIG. 8A is a sectional view taken along the line A--A in FIG. 8, and FIGS. It is a longitudinal side view which shows the main part of 4th Example, respectively. 1... Buckle, 2... Support member (support rod), 3...
... Frame, 3a... Sheath-shaped part, 3b... Box-shaped part,
lO... Cable (wire), 11.12... Drive member (drive pulley), 13... Driving force generator Hi I

Claims (1)

[Claims] The support member of the buckle (1) to which the seat belt is connected (
2) is guided by the frame (3) so as to be movable from the relaxed position of the seat belt in the direction of tightening the seat belt, and the support member (2) is guided by the cable (
The driving members (11, 12) are connected to each other via the cables (10) and the driving members (11, 12) are connected to each other to pull the cable (10) in an emergency.
) A seatbelt tensioning device in which a frame (3) is provided with a driving force generating device (13) that provides a driving force to ) and a box-like part (3b) that protrudes forward and backward from the lower end of this sheath-like part (3a), forming an inverted T-shape. The driving members (11, 12) and the driving force generating device (
13) A seatbelt tensioning device characterized by being provided with.