JPH0971219A - Slip guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the take-up performance when a webbing is taken up and the feeling of operation when the webbing is drawn out by forming a contact part with the webbing out of a mixed resin of a resin material with high mechanical strength and one with small coefficient of friction and also making a mixing rate of the resin material with small coefficient of friction in the mixed resin into a specific weight percent. SOLUTION: A ring-shaped reinforced member 3 forms a belt slot 5 through which a webbing is inserted and an outer surface thereof is covered with a resin coverture 4 molded integrally. The resin coverture 4 consists of a mixed resin where such a resin material with small coefficient of friction and good sliding performance as polyolefin resins, such as a polyethylene, is mixed by 25 to 40 weight percent with a base material of polyamide, such as a polyamide 6 with high mechanical strength. Therefore, a lower end part 6 of the belt slot 5 is covered with the resin coverture 4 with small coefficient of friction so that the sliding movement in a webbing turnaround part of the belt slot 5 is allowed to be smooth, resulting in the good operativity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved slip guide that changes the direction of a webbing to guide the webbing to a predetermined position.

[0002]

2. Description of the Related Art Conventionally, as a seat belt device for holding a vehicle occupant or the like safely in a seat, there is a three-point seat belt device using continuous webbing. In this type of seat belt device, as shown in FIG. 7, one end of the webbing 10 is locked to the retractor (winding device) 20, and the other end passes through the through anchor 21 and the lower end of the center pillar 22. Anchor plate 27 pivotally supported by
The seat belt 24 is engaged with a buckle 25 that is erected in a substantially central portion of the vehicle body, by engaging a slouting 24 that is disposed in the webbing intermediate portion between the anchor plate 27 and the through anchor 21 with the buckle 25 that is erected in the substantially central portion of the vehicle body. I am restrained to 26.

[0003] In addition to the through-anchor 21 and the sluting 24, the three-point seat belt device has a belt guide, a through-belt (not shown), or a retractor outlet at the outlet of the retractor. Webbing 10 like webbing guide
There are many slip guides that change the direction of the webbing 10 to guide the webbing 10 to a predetermined position.

A webbing 1 is used for such a slip guide.
0 is provided, and the webbing 10 inserted into the elongated hole directly contacts and slides. Therefore, in order to improve the winding performance when winding the webbing and the operation feeling when pulling out the webbing, it is necessary to suppress the frictional resistance at least at the contact portion of the slip guide with the webbing as low as possible. The surface shape is smoothed or surface treated by. Further, some of the slip guides must bear a load when the vehicle collides, and it is necessary to have sufficient mechanical strength so as not to be deformed when a load is applied.

However, generally, a resin material having high mechanical strength does not have good slidability, and a low-friction material having a small friction coefficient and good slidability tends to have low strength, so that mechanical strength is not deteriorated. It was difficult to improve slidability. Therefore, for example, as in the seat belt supporting device disclosed in Japanese Patent Laid-Open No. 52-62821, a material having a low frictional resistance such as a fluororesin is formed into a sheet and wound around a sliding portion, or a material having a low frictional resistance. There is a structure in which the sliding portion is coated to reduce the frictional resistance of the contact portion with the webbing.

[0006]

However, as described above, a slip guide is constructed by forming a material having a low frictional resistance into a sheet and winding it around a sliding portion, or coating a material having a low frictional resistance on the sliding portion. In that case, additional processing such as fixing of these sheet materials or coating of a low friction material occurs.

Further, in order to keep the fixing strength of the sheet material fixed to the sliding portion of the slip guide and the adhesion strength of the coating film to the sliding portion of the slip guide, which is the base material, above a certain required level. However, it is necessary to manage the work fairly carefully. Therefore, the slip guide as described above
There is a problem in that the number of complicated processing operations increases and the manufacturing cost increases as compared with a slip guide that is simply formed by molding a resin material.

That is, an object of the present invention is to solve the above-mentioned problems, and by applying a resin coating having good slidability of the webbing and high mechanical strength, the windability at the time of winding the webbing and the webbing extraction It is an object of the present invention to provide an inexpensive seat belt through anchor with improved feeling of operation at the time.

[0009]

Means for Solving the Problems As a result of intensive studies by the inventors of the present application, the mixing ratio and mechanical ratio of a resin material (low friction material) having a small friction coefficient to be mixed with a resin material having a high mechanical strength as a base material Since the relationship of characteristic changes differs depending on the type of mechanical characteristics, it was found that it is possible to obtain a convenient mixed resin according to the purpose of use by utilizing this phenomenon.

That is, the mechanical strength and slipperiness as the basic characteristics required for the slip guide change substantially in proportion to the mixing ratio of the low friction material mixed with the resin material having high mechanical strength. On the other hand, the change in the slipperiness has a remarkable effect even when the mixing ratio of the low friction material is small, and the effect is remarkable in the mixing ratio within a certain specific range. Also,
The thermal cycle cracking resistance is a change tendency with respect to the mixing ratio of the low friction material, and an intermediate change between the change in mechanical strength and the change in slipperiness is recognized.

In view of the above, an object of the present invention is to provide a slip guide that changes the direction of the webbing in order to guide the webbing to a predetermined position. At least a contact portion with the webbing has a resin material having high mechanical strength and a small friction coefficient. It is made of a mixed resin with a resin material, and the mixing ratio of the resin material having a small friction coefficient in the mixed resin is 25 to 40.
Achieved by a slip guide characterized by a weight percentage.

The mixing ratio of the resin material having a small friction coefficient in the mixed resin is more preferably 30 to 35% by weight. In addition, the resin material having high mechanical strength in the present invention is a resin material having a bending strength of 600 kg / cm ² or more, and preferably a polyamide-based material such as polyamide 6, a resin in which a reinforcing material is added to polyacetal, or polypropylene, Polycarbonate or the like is used. Further, the resin material having a small friction coefficient and good slidability in the present invention means
A resin material having a dynamic friction coefficient of 0.15 or less, preferably a polyolefin resin such as polyethylene and polypropylene or a tetrafluororesin is used.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a slip guide of the present invention will be described in detail below with reference to the accompanying drawings. The through anchor 1 for a seat belt shown in FIGS. 1 and 2 is a mounting bracket 2 formed by pressing a steel plate or the like.
And a ring-shaped strength member 3 formed by bending a round bar made of steel into a flat ring shape. The mounting metal fitting 2 is folded and held to hold the ring-shaped strength material 3 and at the upper end of the mounting metal fitting 2. Has a through hole 7 through which the mounting bolt penetrates. The ring-shaped strength member 3 forms a belt slot 5 into which the webbing 10 is inserted,
The outer surface thereof is covered with a resin coating 4 which is integrally molded.

The resin coating 4 is made of a polyamide material such as polyamide 6 which is a resin material having high mechanical strength, a resin in which a reinforcing material is added to polyacetal and polypropylene, a base material such as polycarbonate, and a polyolefin resin such as polyethylene and polypropylene. 25-40% by weight of a resin material with a small friction coefficient and good slidability, such as
It is preferably composed of a mixed resin mixed in an amount of 30 to 35% by weight, and has a high mechanical strength and a low friction coefficient.

The webbing 10 inserted into the belt slot 5 of the through anchor 1 used in the three-point seat belt device for restraining the occupant to the seat as in the conventional case.
Is folded back by the belt slot 5 and slides longitudinally along the lower edge 6 of the belt slot 5,
Since the lower edge portion 6 is covered with the resin coating 4 having a small coefficient of friction, it is possible to smoothly slide the belt slot 5 at the folded portion of the webbing so as to improve the operability when pulling out the webbing and winding the webbing. You can

Further, even when a tension is generated in the webbing 10 and a load is applied to the lower edge portion 6 of the belt slot 5 in an emergency such as a vehicle, the resin coating 4 has high mechanical strength and high heat cycle crack resistance. Since it has, the load acting on the lower edge portion 6 can be supported without being deformed. Further, since the resin coating 4 is formed by coating the belt slot 5 with a desired mixed resin which has been adjusted in advance by integral molding, a complicated processing operation is not required and an increase in manufacturing cost is prevented. You can

Therefore, the through anchor 1 is inexpensively provided with the resin coating 4 having good slidability of the webbing 10 and having sufficient mechanical strength, and the windability at the time of winding the webbing and the operation at the time of pulling out the webbing are obtained. The through-anchor for seat belts has a good feeling. In the seat belt through anchor 1 in the above-described embodiment,
The lower end surface of the mounting member 2 and the entire surface of the ring-shaped strength member 3 are covered with the resin coating 4. However, according to the gist of the present invention, in the through anchor in which only the peripheral portion of the belt slot 5 is resin coated. Is also applicable.

The slip guide of the present invention is not limited to the through anchor for a seat belt as described above, and it goes without saying that various forms such as a belt guide and a through belt can be adopted. For example, although the retractor 31 shown in FIG. 3 is attached to the vehicle body panel by fastening means such as bolts, the webbing 10 is provided at the retractor outlet so as not to inadvertently come into contact with other members due to restrictions of the vehicle body structure and attachment position. It is inserted through the webbing guide 33 arranged in.

As shown in FIG. 4, the webbing guide 33 has an insertion opening 35 through which the webbing 10 is inserted, and a holding portion 36 extending outward from the peripheral edge of the insertion opening 35. It is a slip guide integrally formed of the same mixed resin as the resin coating 4 of the through anchor 1, and has a high mechanical strength and a low friction coefficient. Therefore, the base back plate 31a of the retractor 31
The webbing guide 33 fitted in the webbing guide hole 34 formed in the upper stay 32 fixed to
It is possible to prevent the edge of the webbing 10 from hitting the webbing guide hole 34, to ensure good sliding of the inserted webbing 10, and also to deform the webbing 10 when tension is generated in an emergency such as a vehicle. Can support the load without.

Further, the mixed resin according to the present invention is not limited to the slip guide as described above, and is applied to various mechanical materials (engineering plastics) which require a resin material having good slidability and high mechanical strength. Of course you can.

[0021]

[Experimental Example] Next, an experimental example of the characteristic change of the mixed resin in the present invention is shown to clarify the effect of the present invention. [Experimental Example 1] First, in comparison with polyamide 6 (trade name: UBE nylon), which is a resin material having high mechanical strength, polyethylene (trade name: Lübmer), which is a resin material having a small friction coefficient and good slidability, is used. In order to investigate the relationship between the slip characteristics and the heat cycle crack resistance when the mixing ratio is changed,
The dynamic friction coefficient and the number of heat cycle cycles were measured for each sample made of a mixed resin formed by changing the mixing ratio of polyethylene to the base material polyamide 6 to 0, 20, 30, 40, and 100% by weight. The results are shown in Fig. 5.

(Measurement conditions) -Measuring device: Surface property measuring and testing device "HEIDON" (manufactured by Shinto Kagaku Co., Ltd.)-Sample size: forming square plate (thickness 2 mm x length 100 mm x)
Horizontal 100 mm) ・ Mating material: webbing (material: polyester) ・ Load: 1000 (g) ・ Speed: 5 (m / min) ・ Measuring environment: dry, room temperature (measuring method) Specimen and mating material have a specified surface pressure. Relative sliding motion was performed under speed, and the dynamic friction coefficient was measured from the sliding resistance at that time.

[Experimental Example 2] Next, the mixing ratio of polyethylene to the base material polyamide 6 was set to 20, 30, 4
The flexural strength and flexural modulus were measured for each sample made of the mixed resin formed by changing it to 0, 50, 70, 100% by weight, and the results are shown in FIG.

(Measurement conditions and measurement method) The flexural strength and flexural modulus of each sample were measured according to the standard ASTM D790 of the American Society for Testing Materials. The bending speed is 5mm
/ Min, the distance between spans was 48 mm.

That is, as is apparent from the results shown in FIG. 5, the coefficient of dynamic friction is significantly reduced when the mixing ratio of polyethylene is 25 to 40% by weight. In addition, the number of times of heat-resistant cycle durability is conspicuously reduced when the mixing ratio of polyethylene is 20 to 50% by weight, but it is not as large as that of the dynamic friction coefficient. On the other hand, as is clear from the results of FIG. 6, the flexural strength and flexural modulus decrease uniformly and uniformly as the mixing ratio of polyethylene increases, and there is no remarkable inflection point as in the case of the dynamic friction coefficient. .

Therefore, in order to satisfy the sliding property which is the basic property for the slip guide, while satisfying the mechanical strength and the heat cycle cracking resistance, from the experimental results of FIG. 5 and FIG. It is understood that the polyamide 6 may be mixed in a weight% range, preferably 30 to 35 weight%.

[0027]

According to the slip guide of the present invention, at least the contact portion with the webbing is mechanically mixed at a mixing ratio within a specific range so as to satisfy not only sliding characteristics but also mechanical strength and heat cycle cracking resistance. It is made of a mixed resin of a resin material having high strength and a resin material having a small friction coefficient.

Therefore, the webbing contact portion of the slip guide can be integrally formed of the mixed resin,
Unlike conventional products, there is no need for additional work such as fixing work of sheet materials with low frictional resistance or coating of low friction materials. Therefore, it is possible to provide an inexpensive seat belt through anchor that improves the winding performance when winding the webbing and the operation feeling when pulling out the webbing.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of a through anchor for a seat belt according to an embodiment of the present invention.

[FIG. 2] A of the through anchor for a seat belt shown in FIG.
FIG.

FIG. 3 is a side view of a retractor including a webbing guide according to another embodiment of the present invention.

4 (a) is a front view of the webbing guide shown in FIG. 3, and FIG. 4 (b) is a cross-sectional view taken along the line BB of FIG.

FIG. 5 is a graph showing the relationship between the mixing ratio of polyethylene to polyamide 6, the dynamic friction coefficient, and the number of heat cycle endurance cycles.

FIG. 6 is a graph showing the relationship between the mixing ratio of polyethylene to polyamide 6 and the bending strength and bending elastic modulus.

FIG. 7 is an explanatory diagram showing a configuration of a three-point seat belt device.

[Explanation of symbols]

 1 Seat Belt Through Anchor 2 Attachment 3 Ring Strength Member 4 Resin Coating 5 Belt Slot 6 Lower Edge 7 Through Hole 10 Webbing

Claims (1)

[Claims] 1. A slip guide for changing the direction of a webbing to guide the webbing to a predetermined position, wherein at least a contact portion with the webbing is made of a mixed resin of a resin material having a high mechanical strength and a resin material having a small friction coefficient. The slip guide is characterized in that the mixing ratio of the resin material having a small friction coefficient in the mixed resin is 25 to 40% by weight.