DE1729790B1 - Process for renewing the rough tread of worn tires for earthmoving machines and heavy off-road vehicles - Google Patents

Description

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worn studs approaches largely removed, the one made of one of the materials to be connected will. Grinding is done by letting the tire pass.

10 rotatable on a rack 14 (Fig. 1) adjacent to the strip 20, although it is preferred

the vulcanized rubber carcass of the tire 10 is buffed by a motor 13 driven 15 is stored. It is essential that the 5 tack while at near extrusion temperature Has circumferential surface for the further steps of the method, it has been shown that the large area of the rens is carefully prepared so that it cleans the interface between the strip 20 and the and is free from dirt, grease or oil. Carcass 10 allows a binding of in the w

In order to avoid that the characteristics of the tires achieve essentially the same strength, even if construction which was originally able to cool from the tire con io of the strips 20, provided that structure chosen, are lost, and to which certain treatment modalities are followed. Around Useful life of the retreaded tire to establish a solid bond between a proportionate longer, it is advantageous that the side walls and cold strips 20 and a vulcanized rubber beads of the tire are not abraded. To preserve this carcass and to avoid having a is in contrast to common practice where 15 layers of low strength are found in the renewed tire entire jacket surface, which is the outer circumference, are the surfaces to be connected with a surface and the side walls includes, is processed. Smeared rubber solvent and then with a To maximize contact area between thin layer of rubber solution covered. To the vulcanized rubber of the carcass of the tire, the solvent of the rubber solution evaporates 10 and the vulcanizable, for the construction of a Pro-20, the strip 20 is arranged so that it the Karins Ensuring serving rubber compound, cash register surrounds and pinned in the right position, the prepared circumferential surface is then covered with around the cleats for the construction of the profile of the

a sub-layer of a strip 20 enclosed. Creating tire 10 is similarly vul-der Strip 20 is extruded from vulcanizable rubber into a strand 30 (FIG. 3). nisable rubber extruded into a flat strip, which forms a trapezoidal cross-section, the width of which is essentially the width of the section and the thickness of which is approximately half prepared circumferential surface of the tire 10 corresponds to its greatest width. Preferably corresponds to and its thickness is significantly less than the cross-sectional shape of the strand 30 (as in FIG whose width is. The word »Kau- F i g. 5) in the shape of an isosceles Tschuk «refers to all elastomers, which for 30 trapezoid to ensure that the gaps the production or renewal of large Ge between the approaches of the formed profile in the country tires, especially for earthmoving machinery, are self-cleaning, The strand 30 is made into a plurality of cleats 31

table elastomers or mixtures thereof. Pre-cut, the length of which corresponds to the width of the parts becomes a section, the length of which corresponds to the circumferential surface of the tire 10 and with the essentially corresponds to the scope of the pre-treated special formation of the tunnels, The area of the tire 10 is immediately after which it is reached when the tire is renewed Extrusion of the strip is intended to be separated from this. Each section of strand 30 is then on and arranged so that the prepared circumferential to the tire 10 in a predetermined direction area of the tire 10 completely surrounds. Applied through a 4 ° circumferential surface and in one forward application the strip 20 is attached by pressure. or temporarily on the vulcanized rubber net to create the desired profile shape, The carcass of the tire 10 is attached (Fig. 2). If the cleats 31 on or near the strand

For the extrusion of the strip 20, the pre-compression temperature will be when it is on the backing preferably an extruder is used, which staples it onto the circumferential surface of the tire 10 allows the mouthpiece to be changed and strips, they can be easily deformed to suit any the required width for different to desired direction transversely to the circumferential surface of the working sizes can be extruded without further ado. Accept tire 10, thereby proceeding with the procedure In addition, such extrusion permits any of the tread designs selected for large tires to be at a faster rate Separating the required section from the 50 gene can be customized. In this compressed place Strand immediately after exiting the slope, it should be noted that the in F i g. 1 dar extrusion press as well as attaching the section to provided special profile training only one the circumferential surface, while the separated shows a certain type of profile formation in which cut essentially still extrusion temperature the process can be used. Additionally having. This is at least 65.5 ° C and is normally 55 for easier deformability of the cleats 31 at about 76.5 ° C, and that at about accomplish the immediate separation and attachment of the Adhesion taking place at this temperature causes cleats 31 to bind them to the substrate below more uniform and firmer adhesive bond most favorable conditions, since the bond between between the vulcanized and the vulcanized- two revenges of freshly extruded, vulcanizable Rubber, as it occurs with lower upper δο barem rubber. Has such a bond surface temperatures would be reached. Because of the essentially the same after vulcanization higher temperature, the more advantageous intrinsic strength such as the cleats 31 themselves and therefore holds shafts of freshly extruded rubber and easily withstood the stresses that the is subject to renewed tires available for the binding in operation. area, the bond achieved is essential 65 The possibility of deforming the near or on stronger than a stud 31 obtained by the use of upholstery extrusion temperature, the rubber binding achieved with a binding plate and its adaptation to some special profile training allowed to fertilize to the strength of a single block, but can be done when using a

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Power-operated tacking device too difficult - special advantages in an open steam container

lead. In this case, the attachment project and increased profile durability of the renewed

direction leads to an undesirable deformation of the studs of the tire. When vulcanizing in an open

31 cause and to distort the desired steam container acts a temperature of about

Lead profile shape. Accordingly, if 5 126.5 ^C C on the renewed profile, it will be

a tread pattern is used, which like a comfort from inside the carcass to the outside

forming the lugs 31 is not required, or in cases, from the profile surface inward. This is in the

in which a labor saving through power-operated, in contrast to the vulcanization practice with compression molds,

Automatic tackers are achieved at a temperature of about 146 ^: C only

should, preferably, the studs 31 only act after they have moved inward from the profile surface. at

to apply cool, analogous to the above application of this last-mentioned method

described procedure for applying the changed the reaching of vulcanization temperatures

Strip 20 is to be traversed. As for applying the superposed surfaces of vulcanized

the cleat 31 is concerned, this takes place the adhesive rubber and vulcanizable rubber that the

bond between two bodies of vulcanizing tires for a much longer period of time

rubber and therefore has a much higher temperature is kept what

higher strength per surface unit than one that often leads to the tread of the tread in

Bond between vulcanized rubber and vulcanized undesirable extent is over-vulcanized. An in

canisable rubber. an open steam container of vulcanized tires

Subsequent to the attachment of the studs 31 to 20 shows a satisfactory vulcanization and is the strips 20 are built on the tire 10 for a shorter period of time on a low one Lugs 31 vulcanized by being kept during rigeren temperature, so that the tread surface retains greater elasticity for a sufficient period of time in an open container, including an erfrei be heated. The required vulcanization time is added to the increased service life. Additionally allowed and temperature depend on the thickness of the 25 the use of an open steam container that deten strips 20 and the studs 31 used with the built-up and attached profile. It has been found, however, that satisfactory appearance tires are vulcanized without distortion Results can be achieved if you can choose a tire by comparing the tire with the Verforrend a period of 6 to 7 hours of tempering, which in some cases was necessary to temperature of 126.5 ° C. 30 to the tire for vulcanization in the mold

It is assumed that the vulcanization of the pressing takes place in an essentially relaxed

the tire 10 built up coarse tread can remain.

1 sheet of drawings

Claims (5)

1 2 The use of a vulcanizable intermediate patent claims: layer is known in a further process for the retreading of vehicle tires (German training 1. Procedure for renewing the coarse code 1219 218). There, a previously professional tread worn tire for earth-covered, vulcanized treads is laid on the intermediate machines and heavy off-road vehicles, and the parts to be connected, from which the worn studs are removed, are placed in an elastic, airtight cover in the tire's tread essentially vulcanized in an autoclave. This known smoothing, driving new lugs from a vulcanization is also complicated and the adhesion of the rubber mixture to the smoothed ₁₀ lugs on the tire is insufficient. Tread are applied, with between Finally a tread renewal process is the lugs and the tread a lower layer ren known, in which the connection between the is introduced, and the tire is then made up of several layers of running to vulcanize the rubber freely heated strip and the tire with the help of a very thin is, characterized in that the 15 layer of rubber adhesive or a solution Introducing the lower layer, which is made entirely of upholstery rubber (Swiss Stripes covering the tread on patent specification 403 289). This is same vulcanizable rubber compound, renewing the cover of vehicle tires, is not from which the studs are made and before but about, with very large tires from Erdbewedem applying the studs to the smoothed ₂₀ transmission machines or heavy off-road vehicles Tread is applied. The studs need to be renewed individually. The ^ 2. The method according to claim 1, thereby problems are caused by the known Laufflächen- ^ indicates that the application of the strip does not affect tire renewal procedures. in a hot, sticky state, preferably with almost extrusion temperature takes place. 25 simple and cheap retreading process to 3. The method according to claim 1 or 2, characterized in that a secure adhesion of the studs to the characterized in that the application of the studs tire surface is guaranteed. This is the case with the takes place in a hot state. initially specified method according to the invention 4. The method according to claim 1 or 2, characterized in that a for introducing the lower layer characterized in that the application of the cleats 30 covering the entire tread from strips is carried out on the strip in the cooled state. the "same vulcanizable rubber compound, 5. The method as claimed in claim 4, characterized in that the studs consist of, and before the indicates that the studs are applied to the smoothed running surface before the studs are applied on the strip which is applied for mutual contact. Coming surfaces of the studs and the strip 35 In the method according to the invention it is cleaned and expediently with a thin rubber solution, the strips in a hot, sticky layer be provided. was preferably at near extrusion temperature to raise. It can be advantageous for the application of the studs 40 should also be applied in a hot state, but in other cases it will be applied in The invention relates to a method for renewing the cool state. The the grobstolligen tread of worn tires for adhesion of the stud is enhanced when prior to the up Λ earthmoving and heavy off-road bring the lugs on the strip which in the worn cleats 45 are removed side contact surfaces coming of the lugs for up tools, , the tread of the tire is essentially cleaned and the tread of the strip smoothed with a thin, new studs made of a vulcanizable rubber solution layer are provided.
Rubber mixture on the smoothed running surface. In the following, the invention is illustrated by hand be brought, with between the studs and the matic drawings of exemplary embodiments Tread an underlayer is introduced, and 50 explained in more detail. It shows the tire is then used to vulcanize the FIG. 1 is a perspective view of a tire Rubber is freely heated. carcass on which a shoulder profile according to the In a known method of this type driving is built up, (German Patent 843 161) the studs with Fig. 2 are a section along the line 2-2 in provided with lateral flanges, which with a lot of hand- 55 Fig. 1, work and under high pressure on the surface F i g. 3 a strand in a perspective view the tire body must be fixed. For cutting into individual studs,
is a cushion made of a soft, Fig. 4 is a section along the line 4-4 of the insert provided with pins on the underside of FIG. 1, Stollen applied, which then on the with adhesive 60 F i g. 5 is a section along line 5-5 of FIG fitted tread of the tire body F i g. 4th and with this z. B. adhered by hammering. The tire 10 comprises side walls 11 and 12, is bound. This process is costly and it goes into the tire foot and requires one special technical facilities for the intermediate outer circumferential surface (Fig. 2, generation of the required pressure (German patent 65 4, 5). The first step in the process is to writing 914319), it also results in only a very un- that the circumferential surface of the tire 10 is smooth perfect adhesion of the studs on the abraded surface is given, which is preferably achieved by renen tread. a grinding process is achieved in which