JPS60124505A - Flap for automobile tire - Google Patents

Abstract

PURPOSE:To aim at the promotion of lightweightiness in a flap, by installing a reinforcement rib, which heightens deformability force in an axial direction of the flap, inplural spots on the outer circumferential surface, in case of the flap being attached to a space between an inner tube of a tubed tire and a rim. CONSTITUTION:A flap 1 is made up of installing two reinforcement ribs 9 in a position where an outer circumferential surface of the flap 1 is trisected, besides installing a valve pad reinfroced part 3 in the vicinity of a valve hole 2 as in the past. These of the reinforced part 3 and the reinforcement ribs are formed into almost uniform uniform thickness at a central part of the outer circumferential surface of the flap 1, while at both sides of the flap 1 beubg expanded in tis diameter little by little, it is formed as decreasing its thickness in proportion as being approached to the side edge. According to the flap 1 like this, deformability in an axial direction is improvable over almost the whole circumference of the flap 1 and, what is more, the promotion of tinness in other parts can be set forward.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to reducing the weight of a flap installed between a tube and a rim of an automobile tire to protect the tube.

(2) Field of Application of the Present Invention The present invention is utilized in tube tires for automobiles, which are often used in large vehicles such as trucks and buses.

(3) Background of the Invention Conventionally, as shown in FIGS. 1 and 2, an automobile tire flap l has a valve pad on the outer surface side (tire inner surface side) near the valve hole 2 for passing the pulp of the tube. It has a reinforcing part 3. This valve pad reinforcing part 3 is pushed by the air pressure filled into the tube from the rim hole formed in the rim to allow the valve passed through the vacuum rev hole 2 of the flap l to protrude outside.
This is provided to prevent the object from flying out. That is, the valve pad reinforcing portion 3 is for partially increasing the deformation resistance of the flap 1 in the circumferential direction. In view of the purpose of providing the valve pad reinforcing part 3, the valve pad reinforcing part 3 is provided only at one location in the vicinity of the valve hole 2 for each flap 1.

On the other hand, in order to meet the recent demand for reducing the weight around tires, it is conceivable to reduce the weight of the flap l.

Especially considering the purpose of the flap 1 to protect the tube, the parts other than the valve pad reinforcing part 3 can be made much thinner and lighter than the current situation.

However, if the parts of the current flap l other than the valve pad reinforcing part 3 are significantly thinned, the flap l will easily deform in its axial direction, and as shown in FIG. flap l when setting
is pushed out in a direction opposite to the pushing direction of the tire 5 due to the frictional force with the rim 4, resulting in being sandwiched between the rim 4 and the bead 6 of the tire 5. This impedes the work of setting the tire 5 onto the rim 4. In addition, this phenomenon is noticeable when the flap l has low rigidity and is soft, such as when the wall thickness of the flap l is thin or when the hardness is low, but if the flap l is made thin and has high rigidity, the flap l becomes There is a risk that it will become brittle and break when pushed into the rim 4, or the tightening force of the flap l will be weakened and it will not be able to be firmly attached to the rim 4, and that it will not be able to fulfill its original purpose of protecting the tube 7. arise. In addition, in FIG. 3, 8 is a valve.

(4) Purpose of the present invention The present invention aims to reduce the weight around the tire by making the flap thinner and lighter without impairing the purpose of the flap flap, which is to protect the tube, and the workability of loading the tire onto the rim. The purpose is to respond to

(5) Overview of the present invention The second feature of the configuration of the present invention for achieving the second object is that, in a flap installed between the tube and rim of a tube-filled automobile tire, the flap The main feature is that the flap lamp for automobile tires is provided with reinforcing ribs that increase the deformation resistance in the axial direction.

According to the above-mentioned Kibatsu IJI, the reinforcing ribs provide a hula.

Since the deformation resistance of the rim in the axial direction is maintained, even if other parts are significantly thinned, the reinforcing ribs prevent large deformation in the axial direction when being pushed into the rim.

(6) Embodiment FIGS. 4 to 6 are views showing an embodiment of the present invention, in which two rectangular reinforcing ribs 9 are formed on one surface in the axial direction on the outer peripheral surface of the flap 1. Also, a valve pad reinforcing portion 3 is formed near the valve hole 2 on the outer peripheral surface side. This valve pad reinforcing portion 3 also has the same shape as the reinforcing rib 9 and is provided in the axial direction of the flap 1, and both improve the deformation resistance of the flap 1 in the axial direction. The two reinforcing ribs 9 and the valve pad reinforcing portion 3 are
Each flap is located at a position that divides the flap l into thirds in the circumferential direction.

The reinforcing ribs 9 and the valve band reinforcing portions 3 have a substantially uniform thickness at the center of the circumferential surface of the first row of flaps, but on both sides of the flap 1 whose diameter is gradually expanded, the thickness increases as they approach the side edges. The thickness is gradually reduced. this is,
This is to prevent the stiffness of both sides of the flap 1 from becoming too strong and making the work difficult when installing the flap 1 into the tire from between the tire beats.

In the flap 1 according to this embodiment, the reinforcing ribs 9 and the valve pad reinforcing portion 3 are made of the same material as the cylindrical portion of the flap l. The reinforcing ribs 9 work together with the valve pad reinforcing part 3 to improve the deformation force in the axial direction over almost the entire circumference of the flap 1, so that when the tire is mounted on the rim, the flap This prevents the tire from being pushed out in the opposite direction to the pushing direction due to large deformation in the direction.

When the reinforcing rib 9 and the valve band reinforcing part 3 are made of the same material as the cylindrical part of the flap 1 as in this embodiment, the flap l
Four parts corresponding to the reinforcing rib 9 and the valve pad reinforcing part 3 are provided in advance in the mold for vulcanization molding, and the flap l
It would be better if it was molded integrally with. However, the reinforcing rib 9 or the valve pad reinforcing part 3 does not necessarily have to be made of the same material as the cylindrical part of the flap l, and is free from the purpose of imparting deforming force in the axial direction to the flap l. You can choose the material. For example, the cylindrical portion of the flap l may be made of hard rubber or may have a reinforcing cloth built into it. In particular, when the reinforcing ribs 9 and the valve pad reinforcing part 3 are made of a different material from the cylindrical part of the flap l, they may be molded separately from the cylindrical part of the flap l and then bonded together later. .

In addition, in this embodiment, not only the reinforcing rib 9 but also the valve pad reinforcing portion 3 is utilized to impart a deformation resistance force 4=J in the axial direction to the flap l. Since the valve pad reinforcing portion 3 is required to function as explained in the “Background of the Invention” section, it is not necessary that the valve pad reinforcing portion 3 and the reinforcing rib 9 have the same shape and thickness.

FIG. 7 shows another embodiment in which reinforcing ribs 9 are provided, in which a large number of reinforcing ribs 9 each having a semicircular cross section are provided at equal intervals on the outer peripheral surface of the flap l.

By providing the reinforcing ribs 9 in this manner, the deformation resistance in the axial direction can be increased almost uniformly over the entire circumference of the flap l. In addition, the adjustment of the axial deformation resistance force to be applied is relatively easy, and there is an advantage that the valve pad reinforcement part 3 does not have to be actively used in the axial deformation resistance direction of the flap 1. be. That is, the valve pad reinforcing portion 3 can be provided from the viewpoint of providing the flap 1 with deformation resistance in the circumferential direction, which is its original purpose.

Furthermore, the cross-sectional shape of the reinforcing ribs 9 may be square, semi-elliptical, or the like.

Next, a specific example will be shown in which reinforcing ribs as explained in FIGS. 4 to 6 are provided on the flaps of size 10.00-20, and the wall thickness of the flap cylindrical portion is reduced to reduce the weight.

The weight of the flap according to the present invention and the conventional flap as explained in FIGS. 1 and 2 was compared in terms of the size and wall thickness of each part as shown in the table below. Further, when tires were set on rims using the flap according to the present invention and the conventional flap, the workability was the same. In the table below, t and T are the wall thicknesses of the flap cylinder portion and the reinforcing rib shown in FIG. 6, respectively, and both of the wall thicknesses are the wall thicknesses at the central portion in the axial direction. W is the circumferential length of the reinforcing rib shown in FIG.

(The following is a blank space) (7) Effects of the present invention According to the present invention, the reinforcing ribs maintain the deformation resistance of the flap in the axial direction, so even if the wall thickness of the flap cylinder portion is significantly thinned, the tire When set on the rim, the flap is pushed out in the opposite direction to the direction in which the tire is pushed in due to the frictional force with the rim, and there is no chance of the flap being caught between the rim and the bead of the tire. Therefore, the wall thickness of the flap tube portion can be made significantly thinner without interfering with the work of setting the tire onto the rim, thereby making it possible to significantly reduce the weight of the flap. Furthermore, by reducing the weight of this flap, it is possible to meet the recent demand for reducing the weight around tires.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional flap, Fig. 2 is a circumferential cross-sectional view thereof, Fig. 3 is an explanatory diagram of problems when trying to reduce weight with a conventional flap, and Fig. 4 is a diagram of a conventional flap according to the present invention. FIG. 5 is a perspective view of the flap, FIG. 5 is a circumferential cross-sectional view thereof, and FIG. 6 is a W-Vl cross-sectional view in FIG. 5. FIG. 7 is a cross-sectional view showing other embodiments in which reinforcing ribs are provided. . 1″: Flap, 2: Valve hole, 3: Valve pad reinforcement part, 9: Reinforcement rib. Applicant Yokohama Rubber Co., Ltd. Agent Yutaka 1) Shan Xiong Fan 3 Figure Fan 4 District Figure 5 Oni Figure 6

Claims (1)

[Claims] 1) A flap for an automobile tire, which is attached between the tube and the rim of a tube-filled automobile tire, and is characterized in that reinforcing ribs are provided at multiple locations on the outer peripheral surface of the flap to increase resistance to deformation in the axial direction of the flap.