JP3184111B2 - Automotive seat belt shock absorber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat for reducing the impact applied to an occupant by extending the seat belt by a predetermined length to loosen the seat belt when an excessive tensile force is applied to the seat belt at the time of a collision of the vehicle. The present invention relates to a shock absorber for a belt.

[0002]

2. Description of the Related Art As a safety measure for an automobile seat belt, a shock absorber (For) that absorbs an impact with an airbag at the time of a collision and slightly relaxes the seat belt to reduce the impact on the chest at the time of a collision.
ceLimiter) is known, an example of which is shown in FIG.
The following is referred to. The shock absorber (1) shown in the figure is a seat belt ELR (Emergency Locking).
In the figure, (2) is a seat belt retractor (retractor),
(3) is a seat belt, and (4) is a load generating unit.

The winding device (2) is rotatably held by an outer frame (holding body) (6) housed in a housing (5), and winds a seat belt (3). A claw (7) is provided on the winding device (2) so as to protrude and retract, and a gear (8) meshing with the claw (7) has an outer frame (6).
Is formed on the inner peripheral surface of the. In normal times, the pawl (7) retreats and the winding device (2) rotates freely with respect to the outer frame (6), while an excessive pulling force is applied to the seat belt (3) at the time of a collision or the like. Then, the pawl (7) pops out and meshes with the gear (8), so that the winding device (2) is fixed to the outer frame (6). The load generating part (4) has a wire (10) wound around the shaft (9) with a constant frictional force, and fixes the outer frame (6) by the wire (10) so as not to rotate.

In the above configuration, the pawl (7) is normally retracted, and the winding device (2) freely rotates with respect to the outer frame (6) to wind up the seat belt (3). On the other hand, if an excessive pulling force is applied to the seat belt (3) at the time of a collision or the like, the pawl (7) jumps out of the winding device (2), meshes with the gear (8) of the outer frame (6), and the winding device. The rotation of (2) stops. At the same time, the wire (10) is pulled out from the wound shaft (9) by applying an excessive tensile force to the seat belt (3), so that the outer frame (6) rotates, and as a result, the winding device (2) rotates and the seat belt (3) is paid out. The pulling force is determined by a frictional force between the wire (10) and a path through which the wire (10) passes.

[0005] Next, as a load generated by the load generating section (4), there is a type that uses a rotational load instead of a frictional force. One example is shown in FIGS. 5 (a) to 5 (d). Show. As shown in FIG. 5 (a), the load generating portion (11) includes a buffer plate (1) along a hollow inner peripheral surface of a hollow spool (13) rotating about a fixed shaft (12).
4) is partially folded and assembled, the folded side end is fixed to the shaft (12), and the spool (13) is
Is attached to the holding outer frame (6) of the winding device (2), and the outer frame (6) is temporarily fixed by the rotational load (about 500 N) of the buffer plate (14).

According to the above construction, the outer frame (6) of the winding device (2) is temporarily fixed by the rotational load of the buffer plate (14), and the spool (13) stops together with the outer frame (6) in normal times. are doing. On the other hand, when an excessive tensile force equal to or more than the rotational load is applied to the seat belt (3) at the time of a collision, the rotation of the winding device (2) with respect to the outer frame (6) stops as described above. At the same time, when an excessive pulling force is applied to the seat belt (3), as shown in FIGS. 5 (a) to 5 (d), the buffer plate (14) is deformed and the spool (1) is deformed.
3) rotates counterclockwise against the rotational load to rotate the outer frame (6), and the seat belt (3) is extended by a predetermined length. At this time, 180 °, 360 °, and 450 °
Figure 5 (b) shows the spool position at each rotation.
As shown in (c) and (d), the maximum rotation angle of the spool (13) is 486 °, which is the maximum feeding position of the seat belt (13).

[0007]

The cushioning device for an automobile seat belt is required to be compact and easy to obtain an equal load. For example, the cushioning device (1) shown in FIG. 4 has a wire (10) connected to a shaft (9). , The load is generated by the frictional force between the two, so the mechanism is slightly complicated and it is difficult to obtain an equal load, the working stroke cannot be large, the restraining force is constant and it can not be set stepwise, etc. The shock absorber having the rotation load generating portion (11) shown in FIG. 5 is compact, but has a complicated mechanism and a rotation of 450.
° (less than one and a half times), there is a problem that it is difficult to obtain an equal load due to the limited amount of seat belt extension.

There is also known a torsion bar system in which the shaft is thinned and the shaft itself is twisted and cushioned when an excessive pulling force is applied to the seat belt. In addition, load control cannot be performed, and there is a problem that load characteristics increase in accordance with rotation and the impact applied to the occupant increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automobile seat belt cushioning device which is compact, can easily obtain an equal load, can control the load in a stepwise manner, and can arbitrarily adjust a seat belt feeding amount. is there.

[0010]

SUMMARY OF THE INVENTION The present invention provides a tubular reel for winding a seat belt for an automobile, and a tubular hole of the reel.
And an excessive tensile load is applied to the seat belt.
Shaft and multiple resistors
When the reel is temporarily fixed to the shaft by the contact load of
The excessive tension load applied to the seat belt
When the ft is locked, the pulling force of the seat belt
A predetermined number of reels against the contact load of each resistor
Comprising a load generating unit to rotate, the load generating unit,
Connected and fixed to the shaft and inside the reel cylinder hole
Fits into one of a plurality of grooves formed over the entire circumference
A resistance portion that generates contact resistance is formed on the outer peripheral surface,
A disk base having an engaging portion formed on the shaft; and a disk mounted on the shaft.
A predetermined number of discs that are loosely fitted coaxially next to the base
And fitted to the other grooves above on the outer peripheral surface of each disc body.
A resistance portion that generates contact resistance is formed, and
Discs with engaging portions for contacting discs formed on the sides of each disc
Composed of a body group and a shaft with excessive pulling force
When the lock is fixed, the tensile force of the disk
The seat belt is extended by a predetermined amount by rotating the reel a predetermined number of times, sequentially and sequentially against each resistance load by each resistance portion of the disk group, starting from the abutting portion .

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cushioning device for an automobile seat belt according to the present invention will be described below with reference to FIGS. 1 (a), 1 (b), 2 and 3. FIG. 1A and 1B are a front sectional view and a side sectional view of a shock absorber (15) according to the present invention.
2 and 3 are perspective views of the disk base and the disk group of the load generating section according to the present invention. In the figure, (16) is a cylindrical reel for winding up an automobile seat belt, (17) is a shaft, and (18) is a load generating unit.

The reel (16) has flanges (1) at both ends.
6a), the automobile seat belt is wound around the outer peripheral surface (16b). The shaft (17) is inserted through the reel cylinder hole (16c), and is locked and fixed when an excessive tensile force is applied to the seat belt at the time of a collision or the like.

The load generating section (18) includes a shaft (17)
A disk base (20) connected and fixed to the key with a key (19);
A predetermined number (three in the illustrated example) of disk bodies (2) which are coaxially loosely fitted to the shaft (17) sequentially from the side of the disk base (20).
1) A disk body group (24) composed of (22) and (23).

The disk base (20) is shown in FIG.
As shown in FIG. 2B and FIG. 2, a cutting blade (resisting portion) (25) having a blade end protruding from the outer peripheral surface, and a torque transmitting engaging convex portion (26) formed near the peripheral edge of the side surface. The blade end of the cutting blade (25) has four grooves (2) formed at a predetermined pitch over the entire inner peripheral surface of the reel cylinder hole (16c).
7) Fitting into the groove (27) in (30) and biting into the inner peripheral surface of the groove to generate contact resistance.

The disk bodies (21), (22) and (23) have cutting blades (31), (32) and (3) each having a protruding blade end on each outer peripheral surface.
3) and each of the engaging projections (34) and (35) formed near the periphery of both side surfaces {shown only in the disk (21) in FIG. 2}.
And each of the blade ends of the cutting blades (31), (32) and (33) has another groove (28) (29) (30) in the cylindrical hole of the reel.
And generate contact resistance by engaging with the inner peripheral surface of the groove.

The operation of the present invention based on the above configuration will now be described. First, in normal times, the shaft (17) is in a rotating state, and the groove (2) on the inner peripheral surface of the reel cylinder hole (16c) is formed.
7) to (30), the cutting blade (25) of the load generating part (18)
(31) Each of the blade ends of (32) and (33) is engaged. The reel (16) is temporarily fixed to the shaft (17) by a cutting blade (25) of a disk base (20) connected and fixed to the shaft (17). In this state, the seat belt is attached to the reel (17). And used normally.

Next, an excessive pulling force (approximately 5
(N) (1000-1000N) is applied to the seat belt, and then the shaft (17) is locked and fixed. On the other hand, the reel (17) rotates together with the disk group (24) against the contact resistance due to the engagement of the cutting blade (25) due to the excessive pulling force applied to the seat belt, and at the same time, the groove is formed by the cutting blade (25). The inner peripheral surface of (27) is scraped over the entire circumference.
Then, when the reel (17) makes one rotation against the cutting resistance (contact resistance) by a predetermined angle {for example, 360 ° minus an angle obtained by subtracting half of the central angle (30 °) of the engagement projection (26)}. As shown in FIG. 2, for example, the (A) surface of the engaging projection (26) is one of the engaging projections (3) of the adjacent disc (21).
The disc (21) is then fixed stationary by engaging with the (B) surface of (4). The cutting resistance can be adjusted by the biting amount and width of the cutting edge of the cutting blade (25) in the radial direction, and disappears after the cutting is completed.

Therefore, similarly to the disk base (20), the cutting blade (31) of the disk body (21) continuously rotates the reel (16) against the cutting resistance while shaving the inside of the groove (28). I do.
Then, the reel (16) moves to the second rotation by a predetermined angle.
Rotates, the other engaging projection (35) engages with one engaging projection (36) of the adjacent disc body (22), and the disc body (22) Stationarily fixed.

In this manner, the inside of the groove portion (29) is continuously cut by the cutting blade (32) of the adjacent disk body (22), and the reel (16) keeps rotating against the cutting resistance. . Furthermore, the groove (30) is taken over by the disk (23).
When the inside is cut off and the reel (16) rotates about three and a half times in the illustrated example and the seat belt is extended by a predetermined length, the reel rotation stops.

The amount of rotation of the reel is determined by the disk (21) (2)
2) Since it is determined by the number of (23), the number of discs can be adjusted and the number of rotations and the amount of feeding out the seat belt can be arbitrarily set stepwise within the allowable range of the reel width. Also, a constant load can be easily obtained by the cutting resistance, and the cutting blade (25)
(31) The cutting amount is adjusted by adjusting the biting amount and width of the blade end in the radial direction of (32) and (33), whereby the cutting load (contact load) can be freely and strongly controlled. Further, by the control, after the moment of the collision, the pulling force applied to the seat belt is gradually reduced, and the impact applied to the occupant can be adjusted and reduced as appropriate. In addition, since it is a rotary type, it takes up little space, is compact, and can be easily incorporated into an existing seat belt device.

Further, as shown in FIG.
8) Cutting blade (25) (31) (32) as resistance part
Deformable solid spheres instead of (33) (40) (41)
It is also possible to use a disc body (20) and a disc body (21).
(22) (23) {However, only the disk body (21) is shown in the drawing}, and the disk base (20) within a range smaller than the sphere radius.
And, it protrudes partially from the outer peripheral surface of the discs (21), (22) and (23). The substantially hemispherical projecting portion is fitted into a substantially semicircular groove having a cross section slightly smaller than the diameter of the sphere, and the reel (16) is rotated while crushing the sphere instead of cutting, thereby generating a predetermined load by crushing. Is also good.

[0022]

[0023]

According to the present invention, there is provided a load generating portion comprising a resistive base and a resistive element group which are engaged with each other on a shaft inserted into a tubular reel for winding up a seat belt, so that the shaft is locked and fixed in a collision or the like. Then, the seat belt is extended by a predetermined length to loosen by successively resisting the respective contact loads of the resistance bases provided in the load generating portion and the resistors of the resistor group in order. Equal load is obtained,
Further, the number of resistors can be adjusted to arbitrarily control the amount of feeding of the seat belt, and the load can be freely controlled by easily adjusting the contact resistance according to the resistor size. Furthermore, it is compact and can be easily incorporated into existing seat belt devices.

[Brief description of the drawings]

FIG. 1A is a front sectional view showing an embodiment of a shock absorber for an automobile seat belt according to the present invention. (B) is a sectional side view showing an embodiment of a shock absorber for an automobile seat belt according to the present invention.

FIG. 2 is a perspective view of an essential part showing an example of a load generating unit of the shock absorbing device for an automobile seat belt according to the present invention.

FIG. 3 is a perspective view of an essential part showing another example of the load generating portion of the shock absorbing device for an automobile seat belt according to the present invention.

FIG. 4 is a schematic side view showing one example of a conventional automobile seat belt shock absorber.

FIG. 5 (a) is a side view of a main part showing another example of a conventional automobile seat belt shock absorber. (B), (c) and (d) show FIG.
The principal part side view at the time of each rotation of 180 degrees, 360 degrees, and 450 degrees of the shock absorber of (a).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 16 Reel 16a Reel cylinder hole 17 Shaft 18 Load generating part 20 Disc base 21-23 Disc body 24 Disc body group 25 Cutting blade 31-33 Cutting blade 26, 35 Engaging part

Claims (3)

(57) [Claims] 1. A cylindrical reel for winding a seat belt for an automobile, and an excessively-slung member inserted into a cylindrical hole of the reel.
Locked when tension load is applied to the seat belt
The reel by the contact load of the shaft and multiple resistors.
While temporarily fixing to the shaft, excessive tensile load
When the shaft is locked and fixed to the belt,
The contact load of each of the above resistor elements is determined by the pulling force of the seat belt.
And a load generating part for rotating the reel a predetermined number of times against the weight.
The load generator is connected and fixed to the shaft.
And formed all around the inner peripheral surface of the reel cylinder hole.
Resistance that generates contact resistance by fitting into one of multiple grooves
Disk with a portion formed on the outer peripheral surface and an engaging portion formed on the side surface
The base and the shaft are coaxially arranged in order from the side next to the disk base.
It consists of a predetermined number of discs that are loosely fitted, and
Generates contact resistance by fitting in each of the other grooves
A resistance portion is formed, and an engagement portion with an adjacent disc is formed.
It is composed of a disk group formed on the side of each disk,
When the shaft lock is fixed by a strong pulling force,
Group of discs starting from the resistive part of the disc base
A seat belt is extended by a predetermined amount by rotating a reel a predetermined number of times against a resistance load of each resistance part in sequence. 2. The reel of claim 2, wherein the resistance portion of the load generating portion is a reel cylinder hole.
The cushioning device for an automobile seat belt according to claim 1 , wherein the cutting blade is a cutting blade that is engaged in a groove formed in an inner peripheral surface . Resistance unit according to claim 3 wherein said load generating section, fitted on the reel cylinder bore inner peripheral surface which is formed in cross-section substantially semicircular arcuate groove portion groove
2. The cushioning device for an automobile seat belt according to claim 1 , wherein the cushioning device is made of a deformable solid hemisphere having a diameter slightly larger than a diameter .