FR2488626A1 - ONE-TORON METAL CABLE FOR ARMING ELASTOMERIC PRODUCTS - Google Patents

Abstract

THE INVENTION RELATES TO A SINGLE STRAND METAL CABLE SUITABLE FOR ARMING ELASTOMERIC PRODUCTS, IN PARTICULAR, VEHICLE TIRE BANDAGES, PRESSURE PIPES AND CONVEYOR BELTS. THREE STEEL WIRES 1, 2, 3 ARRANGED PARALLEL TO ONE TO THE OTHER AND GENERALLY LOCATED IN A PLANE, FORM A NON-TWISTED STRAND AROUND WHICH A FOURTH STEEL WIRE IS WOUND 4.

Description

The present invention relates to a single-strand wire rope capable of

  to be used for arming elastomeric products, in particular motor vehicle tires, pressure hoses,

conveyor belts and others.

  It is known to use metal strands to arm and reinforce deformable rubber products. These metal strands consist of several (normally three, four or five) twisted individual metal strands, these metal strands preferably having a

  brass coating to increase the adhesion strength between the metal strand

  and the rubbery material. During the manufacture of these strands, one starts with very thin steel wires generally having a diameter lying between 0.10 and 0.40 mm. These threads are joined together in strands of the type described above.

  by means of a single twisting device.

  The conditions imposed on these metal strands relate to tensile stresses, bending stresses and axial compressions, but

  lower wear, corrosion, fatigue and other

tions.

  Due to the constant progress made mainly in the construction

  pneumatic tires of motor vehicles, as well as due to various factors that promote corrosion in road traffic, for example, salt on icy roads, and also

  general economic factors involved in the cost price, manufacturers

  cants are forced to look for new types of strands. In fact, one of the desired properties in the new types of strands is the total impregnation capacity of the steel of these strands by the elastomeric material. In order to achieve this property, as described in the German patent application DE-OS 26 19 086, it has been sought to give the strands a structure as open as possible. Therefore, the advantage of these metal strands is based on the principle of a structure as open as possible, thus increasing the impregnation ability, the strength of the metal son integrated into the structure to be involved in a measurement also

as high as possible.

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  The cable described in the aforementioned patent application of the Federal Republic of Germany consists of spirally arranged wires, as well as one or more individual wire-wrapping wires which are twisted on two or more individual center cables of steel. but which are not twisted around each other. These central wires are of the same helical shape. They are placed next to each other and against each other so that each of the central wires comes into linear contact with at least one other central wire, the nip extending in parallel

  to the direction of these central threads, while the yarns of wrapping are dis-

placed in a helix.

  The present invention aims to propose a reinforcing cable in front of

  be made with a light structure, whose strands have a complete shape

  open and in which the strength of all the wires used

  for the construction of this cable usually occurs at its maximum.

  This object is produced by means of the metal cable according to the invention which is characterized in that three steel wires arranged parallel to one another and generally situated in a plane form a non-twisted strand which is wrapped by a fourth wire a cable pitch calculated in such a manner that the length of this fourth steel wire exceeds the total length of the cable by at most 3%, at least two of the three parallel steel wires being crossed at least once on one maximum distance of 15 cm, while

  all the steel wires are preformed and pressed into one another.

  Preferably, the three parallel steel wires, as well as the fourth steel wire, have identical diameters generally between 0.1

and 0.4 mm.

  Since, according to the invention, the three parallel steel wires are juxtaposed and the fourth steel wire which surrounds them, has a step of

  important wiring, this is a structure that is practically open to

  and which satisfies the conditions imposed with regard to the

studied at the impregnation.

  The three parallel steel wires touch each other because of the shape imparted to the structure according to the invention essentially on

linear contact surfaces.

  Moreover, thanks to the shape imparted to the structure of the metal strand followed by

  In the invention in which all steel wires provide their intervention, compared to known structures, there is a lower loss of tensile strength, thus contributing to increase the endurance limit resistance, while the modulus of elasticity is not strongly modified

  compared to previously known structures.

  When relaxed, the metal strand thus produced is free of torsion (balanced) and rectilinear, which is an ideal condition, by

  example, in the manufacture of calendered layers for

  truction of pneumatic tires of motor vehicles.

  This absence of torsion and this straightness result from the combination of the following measures adopted during manufacture: the three parallel steel wires situated in a plane are exchanged with each other after certain lengths, thus compensating also at the same time the differences in length and quality; - the steel wrapping wire is pressed firmly on the parallel wires

  and it is subject to prior formatting with these.

  By realizing in this way the metal strand having the following structure

  the invention, this strand acquires a very high mechanical stability.

  Other advantages and features will emerge from the description below.

  after given with reference to the accompanying drawings in which: - Figures 1, 2 and 3 are cross sections of conventional strands of metal son; FIG. 4 is a front view of the structure illustrated in FIG. 2;

  FIG. 5 is a cross-section of the metal cable according to FIG.

vention; while

  - Figure 6 is a front view of the same cable.

  As regards the metal strands previously known and illustrated

  FIGS. 1, 2, 3 and 4 show three, four or five metal wires tor-

  saddled together form a strand. These wires all have a center forming a space

  free and giving rise to the disadvantages described.

  In contrast to this known embodiment, in its cross section illustrated in FIG. 5, the metal strand according to the invention has a completely open structure resulting from the parallel strands (1-2-3) situated in a plane

  and to which the wrapping strand 4 imparts mechanical stability.

  FIG. 6 illustrates this covering, the wiring pitch and the phase being chosen so that there is no buckling in the strand at the points.

  crossing the three parallel steel wires.

  As can be seen, unlike twisted strands, the structure

  of the strand according to the invention illustrated in FIGS. 5 and 6 is complete.

  open and allows, during the calendering, to ensure a thorough impregnation

  plete, by the rubbery material, all the co-operating metallic threads

  In this matter; there is no central hollow space.

  The rubbery material can ensure an impregnation of all parts and thus, the metallic threads are permanently protected against corrosion,

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  while preventing them from adhering to the rubbery material, which would have

  the effect of significantly altering these wires.

  Since the parallel and impregnated metal wires are

  only have a linear contact, the wear resistance is reduced and, as already indicated, since the various treated metal wires generally contribute fully, by their strength, to ensure the quality of the strand, thus obtaining a strand of a diameter as small as possible, thus favorably influencing the cost price of the calendered material. The manufacture of the strand takes place easily by fully satisfying the

  conditions imposed with regard to the economic factor.

  Of course, the present invention is not limited to the modes of

  described and illustrated embodiments; it is capable of many

  rants accessible to those skilled in the art, depending on the intended applications

  and without departing from the spirit of the invention.

Claims (7)

  1.- Single-strand wire rope suitable for arming elastomeric products, in particular pneumatic tires for vehicles, pressure pipes and conveyor belts, characterized in that three steel wires (1, 2, 3) arranged parallel to each other and generally located in a plane, form a non-twisted strand around which is wound a fourth wire (4) of steel.   2.- steel cable according to claim 1, characterized in that the length of the fourth wire (-4) out of steel exceeds 3% maximum total length cable.   3. Steel cable according to any one of claims 1 and 2,   characterized in that at least two of the three parallel steel wires (1, 2, 3)   intersect at least once for a maximum distance of 15 cm.   4. Steel cable according to any one of claims 1 to 3,   characterized in that all the wires (1, 2, 3, 4) are preformed and pressed into each other.   5. Steel cable according to any one of claims 1 to 4,   characterized in that the three parallel wires (1, 2, 3) of steel, likewise   that the fourth wire (4) have, preferably, identical diameters.   6. Steel cable according to any one of claims 1 to 5,   characterized in that the diameter of the steel wires is between 0.1 and 0.4 mm.   7.- steel cable according to any one of claims 1 to 6,   characterized in that the wiring pitch and the phase of the fourth steel wire (4) extend between the crossing points of the three wires (1, 2, 3) parallel steel.