JPH0451607Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a tongue plate that is used in a seat belt device and is engaged with a buckle, and is particularly applicable to a three-point seat belt device in which the webbing is continuous. The present invention relates to a preferred tongue plate for a seat belt device.

[Prior Art] In a three-point seat belt device in which the webbing is continuous, the tongue plate that is engaged with the buckle is provided with a through hole that penetrates in the plate thickness direction, and the middle part of the webbing is inserted into this through hole. It is becoming more and more common.

As shown in FIG. 9, in the tongue plate 12 in which two through holes 11 are formed and the webbing 10 is routed as shown, a large frictional force is generated between the webbing 10 and the tongue plate 12. . Therefore, the tongue plate 12 does not slide down along the webbing 10, and the webbing 10 can be stored in the retracted state without any special operation as shown in FIG. ) is located near the lip joint 14, so it has the advantage of excellent operability when attaching the webbing 10.

By the way, the part of the webbing 10 that has been wound around the tongue plate 12 when the webbing 10 is attached moves to a position beyond the slip joint 14 when the webbing 10 is stored, so the tongue moves with the webbing 10 due to frictional force. Before winding of the webbing 10 is completed, the plate 12 comes into contact with the slip joint 14 as shown in FIG. 10. When the tongue plate 12 comes into contact with the slip joint 14, the frictional force generated between the webbing 10 and the tongue plate 12 acts as a braking force against the webbing winding force generated by the winding device.

Therefore, in order to make it possible to store the webbing 10, it is necessary to set a large webbing take-up force, which increases the tension generated in the webbing, presses the passenger, and impairs the comfort of wearing the webbing 10. There's a problem.

In the embodiment of the tongue plate filed in Japanese Patent Application No. 61-181632, as shown in FIG. Reduces frictional force. The tongue plate 12 also has a latch hole 16 into which a buckle locking member is latched.
A continuous enlarged hole 18 is provided to prevent the tongue plate 12 from interfering with the operator when the tongue plate 12 is engaged and disengaged, and to reduce the weight.

As a result, even if the frictional force between the tongue plate 12 and the webbing 10 is reduced, the weight of the tongue plate 12 is reduced. Does not impair storability.

However, since the frictional force is proportional to the tension of the webbing 10, that is, the webbing winding force of the winding device, the tongue plate 12
Since the frictional force between the webbing 10 and the passenger seat is reduced, when driving with the webbing 10 on the passenger seat etc. retracted, the frictional force along the webbing 10 is reduced, especially when vibrations occur in the vehicle due to the influence of the road surface. It becomes easy to slip off.

Furthermore, as shown in FIG. 12 in Japanese Patent Application Laid-Open No. 48-81226, the tongue plate 12 is guided to the slip joint 14 as shown, and the tongue plate 12 abuts against the slip joint 14. After that, the frictional force generated between the webbing 10 and the webbing 10 can be reduced.

However, if the webbing winding force decreases due to deterioration of the spring during use, the tongue plate 12 cannot be guided as shown in FIG. 12, and the webbing 10 will not be fully stored.

[Problems to be solved by the invention] In view of the above, the present invention provides a tongue for a seat belt device that does not impair webbing retractability even when the webbing winding force is reduced, and does not slip down along the webbing. The purpose is to provide plates.

[Means for Solving the Problems] The tongue plate for a seat belt device according to the present invention includes a main body that is provided with an engagement portion with a buckle and a through hole that penetrates the engagement portion in the thickness direction. a webbing wrapping part that is movably supported by the main body in the thickness direction of the main body and forms two through holes; and a biasing means for urging the webbing wrapping part in the thickness direction of the main body. It is configured with the following.

[Function] In the present invention having the above configuration, when tension is generated in the webbing, the webbing winding part is moved in the thickness direction of the main body part against the biasing force of the biasing means, and the part of the tongue plate is moved by the tension of the webbing. The posture of the webbing becomes straight. In this state, the frictional force due to the tension of the webbing decreases, but since the frictional force due to the biasing force of the biasing means is generated, the tongue plate is supported by the webbing without slipping down.

When the tension of the webbing decreases, the webbing winding part is urged by the urging means to move and strengthen the bending state of the webbing at the tongue plate, so that the tongue plate is supported by the webbing by the frictional force generated by its own weight. Ru.

[Embodiment] FIGS. 1 to 7 show a first embodiment of a tongue plate for a seat belt device according to the present invention.

As shown in FIGS. 1 and 2, in the tongue plate 20 of this embodiment, the main body portion 22 has an engaging portion 24 with a buckle (not shown) formed of a thick steel plate, and a portion of this engaging portion 24 is formed of a thick steel plate. is embedded in the extension part 26 made of resin and is integrally connected to the extension part 26.
The engaging portion 24 is formed with a latch hole 28 into which a lock member provided on the buckle is latched, and the extension portion 26 is formed with a rectangular through hole 30 that passes through the engaging portion 24 in the thickness direction. has been done.

In addition, as shown in FIGS. 1B and 3, in the extension part 26, rectangular parallelepiped-shaped recesses 32 are formed in the inner circumferential wall 30A of the through hole 30 so as to face each other in the width direction of the engaging part 24. has been done. In the recessed portion 32, slits 34 are formed in inner circumferential walls 32A facing each other. Both ends of a leaf spring 36 bent into a substantially hat-shaped cross section as shown in FIG. 4 are movably inserted into the slit 34, and the leaf spring 36 is disposed in the recess 32.

On the other hand, the webbing winding part 38 of this embodiment is constructed by embedding a middle part of a strength part 40 made of a rectangular thick steel plate in an exterior part 42 made of resin and joining them together. This webbing wrapping portion 38 is a strength portion 4 protruding from both ends of the exterior portion 42.
0 is inserted into the recess 32, and is supported by the extension 26 while being held between the leaf spring 36 and the inner circumferential wall 32B of the recess 32, as shown in FIG. 1B. As a result, the through hole 30 is divided into two by the webbing wrapping portion 38, and two through holes 44 and 46 are formed in the extension portion 26.

When no external force is applied to the webbing wrapping portion 38, the exterior portion 42 is flush with the extension portion 26, but both ends of the strength portion 40 are connected to the inner peripheral wall 32C of the recess 32 [see Fig. 1B]. ] When an external force is applied to push the plate spring 36 toward the same direction, the leaf spring 36 is elastically deformed and moves in the same direction.

As shown in FIG. 5, this tongue plate 20 has a webbing 49 that has been pulled out from a webbing retractor (not shown) against the retracting force of a full spring and then wrapped around a slip joint 47 and folded back. The intermediate portion is inserted into through holes 44 and 46. The webbing 49 in the tongue plate 20 is arranged so that when tension is applied to the webbing 49, the webbing winding portion 38 elastically deforms the leaf spring 36 and can move. passes through the upper surface of the exterior part 42.

In addition, in order to further increase the rigidity of the extension part 26 that supports the winding part 38, a pair of rigid plates or the like may be insert-molded inside the extension part 26 above and below the recessed part 32.

Next, the operation of this embodiment will be explained.

When the passenger wears the webbing 49, the tongue plate 20 is engaged with a buckle (not shown), and in this state, the webbing 49 is wrapped around the webbing winding part 38 and folded back.

When the tongue plate 20 is disengaged from the buckle (not shown), the webbing 49 is biased by the full spring to the webbing take-up device and wound up into a stored state.

At this time, at the initial stage of winding the webbing 49, the through hole 4
Webbing 49 of the part inserted through 4 and 46
No large tension is generated. Therefore, the large tension of the webbing 49 does not act on the webbing winding portion 38, so the exterior portion 42 is substantially flush with the extension portion 26, and the webbing 49 is largely bent at the tongue plate 20. . As a result, the tongue plate 20 moves together with the webbing 49 without changing its position relative to the webbing 49 due to the frictional force generated between the tongue plate 20 and the webbing 49 due to its own weight, so that the tongue plate 20 descends along the webbing 49. There is no need to put it away.

When tension is generated in the portions of the webbing 49 inserted through the through holes 44 and 46, the webbing wrapping portion 38 is moved against the urging force of the leaf spring 36 depending on the strength of the tension. As a result, as shown in FIG. 6, the webbing 49 is gently bent at the tongue plate 20, and the frictional force generated between the webbing 49 and the webbing 49 due to the shape of the tongue plate 20 is reduced. However, in this state, the leaf spring 36 is elastically deformed.
Since the shape restoring force is added to the tension of the webbing 49, in other words, the frictional force generated by the shape restoring force of the leaf spring 36 is added, so the tongue plate 20 falls along the webbing 49 under its own weight. Never.

In this embodiment, the frictional force generated between the tongue plate 20 and the webbing 49 is set to be constant by tuning the urging force of the leaf spring 36. This frictional force is such that even when acceleration is applied to the tongue plate 20 due to vibration of the vehicle, the tongue plate 20 is
9, and smaller than the frictional force generated between the tongue plate 12 and the webbing 10 under tension, as shown in FIG. 9 and explained in the previous section. .

Therefore, even if the winding force of the webbing winding device is reduced compared to the conventional one, the retractability of the webbing 49 is not impaired, and the tongue plate 20 is prevented from sliding down along the webbing 49 when the webbing 49 is in the retracted state. do not have.

Furthermore, even if the tension generated in the webbing 49 decreases or no longer occurs in the webbing 49 when the webbing 49 is in the retracted state due to deterioration in the winding force of the webbing retractor during use, the webbing can be unwound. The portion 38 is biased by the leaf spring 36 and returns to its original position (the completely returned state is shown in FIG. 7), keeping the frictional force generated between the webbing 49 and the tongue plate 20 constant. Therefore, even in such a case, the tongue plate 20 will not slide down along the webbing 49.

Place the stored webbing 49 on the tongue plate 2.
0 and pulls it out from a webbing take-up device (not shown) against the biasing force of the full spring, and engages the tongue plate 20 with a buckle (not shown), so that the occupant is placed in the webbing 49 described above. When pulling out the webbing 49,
Since tension is generated in the webbing 49 and the webbing winding part 38 is moved against the biasing force of the leaf spring 36, the tongue plate 20 slides on the webbing 49 more smoothly than before. Therefore, the webbing 49 can be smoothly pulled out, and the operability of attaching the webbing 49 is also improved.

In this way, in this embodiment, the frictional force generated between the webbing 49 and the tongue plate 20 can be kept constant at all times, so that the setting of the winding force of the webbing winding device can be easily designed.

FIG. 8 shows a second embodiment of the present invention corresponding to FIG. 1B. In this embodiment, the leaf spring 36
The leaf spring 36 of the above embodiment was elastically deformed by being pulled by the webbing wrapping portion 38, but the webbing wrapping portion 3
The only difference is that it is elastically deformed when pressed by 8, and the basic functions and effects are the same.

[Effects of the invention] As explained above, the tongue plate for a seat belt device according to the invention does not impair webbing retractability even when the webbing take-up force is reduced, and does not slide down along the webbing. have an effect.

[Brief explanation of the drawing]

1A is a plan view showing a first embodiment of the tongue plate for a seat belt device according to the present invention, FIG. 1B is a sectional view taken along line B-B of FIG. 1A, and FIG. Fig. 3 is a partially enlarged exploded perspective view of Fig. 2, Fig. 4 is a perspective view of the leaf spring taken out from Fig. 3, and Fig. 5 shows the tongue plate of the embodiment assembled to the webbing. FIG. 6A is a perspective view showing a state in which tension is generated in the webbing in FIG. 5, and FIG.
FIG. 7A is a perspective view showing a state in which no tension is generated in the webbing in FIG. 5;
Fig. 7B is a side sectional view of Fig. 7A, and Fig. 8 is a side sectional view of Fig. 1.
A sectional view of the second embodiment of the present invention shown corresponding to FIG. B, FIG. 9A is a perspective view showing a conventional general tongue plate, FIG. 9B is a side sectional view of FIG. 9A,
FIG. 10 is a perspective view showing the state in which the webbing with the tongue plate of FIG. 9 assembled is in the middle of being stored;
FIG. 11A is a perspective view of a tongue plate that can alleviate the problem of the tongue plate in FIG. 9, FIG. 11B is a side sectional view of FIG. 11A, and FIG. 1 is a side view of a seat belt device that can alleviate the problem; FIG. 20...Tongue plate, 22...Main body, 2
4... Engagement part with buckle, 30... Through hole, 3
6...Plate spring, 38...Webbing winding part, 49
...Webbing.

Claims (1)

[Scope of utility model registration request] A tongue plate that is used in a seat belt device and is engaged with a buckle, the main body being provided with an engagement portion with the buckle and a through hole passing through the engagement portion in the thickness direction; A webbing winding part that is movably supported by the main body in the thickness direction of the main body and has two through holes, and a biasing means that biases the webbing winding part in the thickness direction of the main body. A tongue plate for a seat belt device.