US3373073A - Elastically extensible band - Google Patents

Description

March 12, 1968 c. H. TURCKSIN ELASTICALLY EXTENSIBLE BAND 2 Sheets-Sheet Filed March 18, 1964 A TYS.

March 12, 1968 C. H. TURCKSIN 3,373,073

ELASTIGALLY EXTENSIBLE BAND Filed March 18, 1964 2 Sheets-Sheet 2 Jnrenfar:

CHRIST/AN H 7ZJEK$IN ATTYJ'.

United States Patent Office 3,373,073 Patented Mar. 12, 1968 3,373,073 ELASTICALLY EXTENSIBLE BAND Christian Heinrich Turclrsin, 27 Saganer Strasse, Detmold Lippe, Germany Filed Mar. 18, 1964, Ser. No. 352,874 Claims priority, application Austria, May 31, 1963, A 4,438/63 Claims. (Cl. 161144) ABSTRACT OF THE DISCLOSURE A band of high elasticity, which is extensible in both the longitudinal and transverse directions, is produced in an extremely simple manner by juxtaposing highly elastic longitudinal threads in side'by-side relationship and connecting them by means of an elastic material so as to form a fiat band. Each of the elastic longitudinal threads consists of an elastically extensible core thread with textile threads Wrapped around the core thread.

This invention relates to an elastic band, a belt or the like, which is extensible both in longitudinal and in transverse direction, and to a method of producing same.

Bands of rubber which are extensible in longitudinal and transverse direction are known. Such bands are only of small elasticity when they have a sufiicient loading strength, specially tensile strength. Moreover, such bands easily tear at their fastening or connecting edges. By incorporating fabric inserts by vulcanizing such bands can be strengthened; but their elasticity becomes still smaller thereby.

It is further known to weave belts of elastically extensible warp threads made of rubber, latex or the like and of weft threads not elastically extensible and consisting of cotton, jute or the like. In this case it is also known to wrap or cover the rubber or latex threads as elastically extensible core threads for protection and for reinforcement without substantially impairing their elasticity. Such belts show at good elasticity and remarkable tensile strength, however, the essential disadvantage that the moving warp and weft threads constantly rub against one another and thus the service life of such belts is considerably reduced owing to the occurring wear.

It is the object of the invention to provide a band or the like which is elastically extensible both in transverse direction and especially in longitudinal direction and permits in comparison with hitherto known elastic bands a substantially simplified production and working and a long service life at a high elasticity.

According to the invention, a band elastically extensible in longitudinal and transverse direction comprises longitudinal threads of a number corresponding to the width of the band and arranged in flat juxtaposed relation and each comprising at least one elastically extensible core thread and textile threads wrapped around said core thread, and an elastically extensible film connecting said longitudinal threads.

The core threads may consist of raw caoutchouc, rubber or the like, and the elastically extensible film may consist of latex, rubber or the like.

Thus, it is not the question of a band of fabric, but of a band which only consists of longitudinal threads known per se and connected in juxtaposed relation by means of an elastically extensible layer, a film or the like of elastic material to form a fiat band. These juxtaposed longitudinal threads show a high elasticity owing to their intimate connection. By means of the elastic material of the extensible layer such a band also shows an advantageous elasticity in transverse direction.

Particular significance must be attached to the wrapped core threads as longitudinal threads. Before wrapping the core threads which expediently consist of raw caoutchouc, they are tensioned to their greatest extensibility, for example 1:6, and then wrapped by several textile threads, such as cotton threads. It may be advantageous to wrap e.g. four textile threads in one direction and e.g. two textile threads in the opposite direction. Through this wrapping the greatest extensibility of the longitudinal threads is indeed reduced, but these longitudinal threads show a surprisingly high elasticity and thus impart a high elasticity in longitudinal direction to the band which is produced by immersing these threads in adhesive liquid, for example, on the basis of latex. The vulcanized adhesive liquid, on the one hand, holds together the juxtaposed longitudinal threads, but on the other hand, provides an advantageous elasticity in transverse direction of the band.

A preferred embodiment of the invention will now be' described by way of example and with reference to the accompanying drawings, in which:

FIG. 1 is a top plan view of a portion of a band according to the invention; 1

FIG. 2 is a cross section through the band of FIG. 1, and

FIG. 3 is a diagrammatic representation of an arrangement for producing the bands from longitudinal threads.

Referring to FIGS. 1 and 2, a band as proposed by the invention consists of a plurality of juxtaposed longitudinal threads 10 each having a core of one or more round or angular raw caoutchouc threads 11 made of latex. These raw caoutchouc threads 11 have, for example, an extensibility of 1:4 to 1:7, preferably 1:5 to 1:6, and are covered under tension (up to the utmost elongation) by textile threads, such as cotton threads, wrapped in opposite directions, e.g. four threads 12 wrapped in one direction and two threads 13 wrapped in the other direction.

' Through this wrapping with non-extensible threads the extensibility of each individual longitudinal thread 10 is adjusted to about the half, for example, to about 1:3.

For producing a band a plurality of longitudinal threads 10 are arranged side by side in accordance with the desired width of the band. The longitudinal threads 10 are uniformly pre-tensioned, for example, to double their length before being immersed for their connection in a liquid adhesive having a high elasticity in the finished state.

When these pre-tensioned longitudinal threads 10 pass through one or preferably several baths, are Wetted or impregnated during this process with an adhesive, for example, an adhesive on the basis of latex, which is elastically extensible in the finished state, and subsequently vulcanized and dried, a band of high elasticity is obtained which is extensible not only in longitudinal direction but within certain limits also in transverse direction.

The production of a band proposed by the invention and only provided with elastically extensible longitudinal threads 10 will now be described in detail with reference to FIG. 3.

Fixedly mounted on a driven shaft or running freely on an axle are a plurality of narrow spools or bobbins 15 around each of which an aforedescribed longitudinal thread 10 with a raw caoutchouc core is wound without pre-tension. The number of these bobbins 15 corresponding to the cross section of the longitudinal thread is determined by the number of closely juxtaposed longitudinal threads 10 necessary for the desired Width of the band.

The longitudinal threads 11 with raw caoutchouc core are pulled off from the bobbins 15 under a certain tension, e.g. 1:2, and subsequently pass through a so-called comb 16 into which passage holes or grooves are worked at a spacing corresponding to the desired spacing of the longitudinal threads 10 located side by side in the finished hand. These passage holes or grooves are thus located at such a small distance from one another as is to be provided forthe longitudinal threads in the finished band. The longitudinal threads pulled off from the bobbins under like pre-tension and aligned by the comb 16 pass through a preliminary bath 17 in which they are treated witha wetting liquid and an adhesive liquid. In this preliminary bath 17 the longitudinal threads are coated with a film of the adhesive liquid and, after leaving this bath, the thinly coated longitudinal threads having their wrapping threads at least considerably wetted, if not even penetrated or impregnated with the adhesive liquid, are dried so that the film of adhesive liquid formed around the longitudinal threads and in their intermediate spaces becomes viscous and thereby already holds the longitudinal threads together.

After such partial connection and coating and preliminary drying of the longitudinal threads the band so formed is guided over a roll 18 provided with grooves or the like and passes through a main bath 19 in which takes place-a further final coating with an adhesive liquid, e.g. on the basis of latex which is especially advantageous. The band coated with a film of adhesive liquid 14 (FIG. 2) is guided over a further roll 20 and then dried in a drying channel 21 following the roll, for which purpose a hot air current of 80 to 120 may be provided. At about 120 vulcanization of the film of adhesive liquid 14 is completed, and the band of longitudinal threads with highly elastic core, which is elastic both in longitudinal and transverse direction, is finished.

The bands produced according to the aforedescribed method may have a width of up to 600 mm. and more. Also several widths may be produced, which together have a final width of 600 mm. or more. For this purpose.

it is necessary to separate the longitudinal threads before they enter the preliminary bath, i.e. to omit one or more longitudinal threads between the individual desired widths of the band. In each of the preliminary and main baths then only one string of the band is coated coherently. Changes in the Width of the band can be made while the device or machine is running without interrupting its operation or even stopping it.

Bands provided with such longitudinal threads show a high elasticity reserve in that by the pre-tension before the wrapping and the further pre-tension of the longitudinal threads before the introduction into the baths, the limit of elasticity is not exceeded, but rather not reached so that the longitudinal threads and thus the bands show an elasticity which does not substantially change during use.

Such bands have special significance as covering belts for the furniture industry. They show a surprisingly long service life and can be cut to length in a simple manner and fastened without tearing out at their fastenings.

It may be expedient to improve the adhesive. liquids preferably consisting of latex in a manner known per se by additions to accelerate the vulcanization or to improve the aging properties of the vulcanized rubber, for example.

The method of producing .such bands may also be modified. Thus, the bobbins can be optionally adapted to different cross sections of the longitudinal threads. The spacing of the grooves in the so-called comb may likewise correspond to different cross sections of the threads. The drying may be carried out in drying chambers which are separate from vulcanization chambers following them. Before drying, it is often advantageous to strip off surplus amounts of the e.g. pasty adhesiveliquid from the coated longitudinal threads which owing to the coating join in a band, and to equalize penetrated adhesive liquid. Ac-

' cording to the desired purpose and the material used, the

transit time of the longitudinal threads in the preliminary bath and the main bath is determined by the thickness of the desired coating which not only adheres to the surface of the wrapping threads, but also cross-links in an advantageous manner with the wrapping threads so that an intimate connection is formed.

I claim:

1. A band elastically extensible in longitudinal and transverse direction composed of longitudinal threads of a number corresponding to the width of the band and arranged in fiat juxtaposed relation and each comprising at least one elastically extensible core thread and textile threads wrapped around said core thread, each of said longitudinal threads having a high elasticity thereby imparting a high elasticity to the band in the longitudinal direction across the entire transverse cross section, and an elastically extensible film connecting said longitudinal threads to thereby provide transverse elasticity.

2. A band as claimed in claim 1 wherein the core threads are composed of material from the group consisting of raw caoutchouc and rubber.

3. A band as claimed in claim 1 wherein the elastically extensible film is composed of material from the group consisting of latex and rubber.

4. A band as claimed in claim 1 wherein the core threads are in a state of tension.

5. A band as claimed in claim 4 wherein a plurality of textile threads are wrapped in opposite directions with respect to each other around each of the core threads.

References Cited UNITED STATES PATENTS 2,013,211 9/1935 Herkenberg 156161 2,380,373 7/ 1945 Alderfer l61175 2,593,284 4/1952 Ewell I6l144 3,032,963 5/1962 Fenner '161144 3,042,569 7/1962 Paul 156-480 3,126,312 3/1964 Nickerson 161-144 MORRIS SUSSMAN, Primary Examiner,

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