METHOD FOR PRODUCING A CLADDING FOR ELONGATED MATERIAL

Abstract

The present invention relates to a method for the production of a cladding for elongated material (2), in particular a sheath for cable sets. In this method, an adhesive tape (3, 4) consisting of a carrier (4) and a first adhesive coating (3) which substantially fully covers the front side of the carrier (4) is combined with an adhesive-free carrier tape (5) such as to form a laminate (3, 4, 5). This is carried out such that the adhesive tape (3, 4) is applied to the carrier tape (5) with its first adhesive coating (3) in such a way that a first projection (U.sub.1) is defined along at least one of the two longitudinal edges of said adhesive tape. According to the invention, the carrier (4) of the adhesive tape (3, 4) is additionally provided with a further second adhesive coating (7) substantially in parts of its rear side.

Claims

1. A method of making a wrap for an elongated object comprising the steps of: providing an adhesive tape consisting of a longitudinally extending base strip and having an inner face, an opposite outer face, and two longitudinally extending and transversely spaced edges, the outer face being substantially completely covered by a first adhesive coating; applying an adhesive-free overlay strip to the adhesive coating on the outer face transversely inward of one outer longitudinal edge thereof to form a laminate while leaving a first exposed edge band at the one of the longitudinal edges; and applying a second adhesive coating to the inner face of the adhesive tape over only it's the area of the inner face.

2. The method according to claim 1, wherein the adhesive tape with its first adhesive coating is applied to the overlay strip, so as to define a second exposed edge band on along the other of the longitudinal edges.

3. The method according to claim 2, wherein the first and second exposed edge bands have a width ratio of 1:1 to 1:5.

4. The method according to claim 2, wherein the adhesive coating is exposed outward on both of it's the first and second exposed edge bands.

5. The method according to claim 1, wherein the adhesive tape has a width that exceeds a width of the overlay strip by at least a width of the exposed edge band.

6. The method according to any one of claim 1, wherein the second adhesive coating is offset toward the first exposed edge band on the inner face of the base strip from a central longitudinally extending plane.

7. The method according to claim 2, wherein the second adhesive coating has a width corresponding approximately to a width of the second exposed edge band.

8. The method according to claim 1, wherein the exposed edge band has a width of 5% to 30% of a width of the adhesive tape.

9. The method according to further comprising the steps of: aligning the laminate with its first exposed edge band; parallel to the elongated object sticking the laminate by the first adhesive coating to the elongated object; wrapping the laminate around the object; and finally bonding the laminate wrapped around the object to itself with the second adhesive coating to form the a longitudinally extending wrap around the object.

10. A sheath for making a wrap for an elongated object having an adhesive tape consisting of a base strip and a first adhesive coating that substantially completely covers the base strip on its outer face essentially, and having an adhesive-free overlay strip adhered to the first adhesive coating so as to leave a first exposed edge band on at least one of two longitudinal edges of the tape, the base strip of the adhesive tape also being provided with another second adhesive coating over part of its area.

Description

[0033] The invention is described in greater detail below with reference to drawings showing a single illustrated embodiment, wherein

[0034] FIGS. 1A to 1C show a method of making a wrap for an elongated object in various method steps, and

[0035] FIG. 2 shows the sheath applied to the elongated object.

[0036] The figures illustrate a wrap 1 for an elongated object 2. The elongated object 2 in this illustrated embodiment, which is not restrictive, includes several cable strands, cable sets, etc., that are combined for use in a motor vehicle. With the help of the sheath 1, the elongated object 2 and/or the individual strands is/are sheathed over their longitudinal extent. Consequently, the sheath 1 corresponds to a longitudinal wrap as a sheath, as shown in FIG. 2, and the production of which is illustrated in detail in FIGS. 1A to 1C, where one can see the sheath 1 and the individual production steps in a stretched-out state.

[0037] In production of the sheath 1, first an adhesive tape 3, 4 provided with an adhesive coating 3 is made available. The adhesive coating 3 covers a base strip 4 of the adhesive tape 3, 4 on its outer face essentially over the full area, as shown clearly in FIG. 1A. The adhesive tape 3, 4 has a width B as a whole.

[0038] The base strip 4 of the adhesive tape 3, 4 may be made of a woven or knit fabric. A PET (polyethylene terephthalate) woven fabric or a polyamide [nylon] woven fabric is used in most cases. In general, however, the base strip 4 may also be designed as a velour base strip or knit base strip. In general, the base strip 4 may be a textile base strip 4 that may basically be designed as a nonwoven.

[0039] The base strip 4 of the adhesive tape 3, 4 may also assume other functions in addition to its basic function of providing an application surface for the adhesive coating 3. It is thus conceivable for the base strip 4 to be provided with a lacquer coating, a film coating, etc. on its surface opposite the adhesive coating 3 in order to protect the cable strands sheathed in this way and/or the elongated object 2 from moisture, for example, splashed water after the sheath has been applied. In this context the base strip 4 may basically also be embodied as a film. The invention here is based on the fundamental finding that, when the sheath 1 is applied to the elongated object 2, the surface of the adhesive tape 3, 4 opposite the adhesive coating 3 is facing outward, and consequently, it can assume the additional function that has been described in a particularly advantageous manner.

[0040] Furthermore, the base strip 4 may function as a heat shield or thermal shield if the sheath 1 is to be applied in the area of hot engine parts, in particular for sheath cables in the engine space of a motor vehicle. In this case, the base strip 4 may be designed as a metal foil. However, it is also conceivable to furnish a textile base strip with a metal foil on its surface opposite the adhesive coating 3 to reflect thermal radiation in particular. Then the metal foil facing outward also functions as a heat shield at the same time.

[0041] The adhesive tape 3, 4 has a width B in the range of about 80 mm to 600 mm. The width B is preferably in the range of 80 mm to 300 mm. The weight of the adhesive tape 3, 4 per unit of area is in the range of 40 g/m.sup.2 to 800 g/m.sup.2 and preferably between 100 g/m.sup.2 and 500 g/m.sup.2. Its thickness may be in the range between 0.1 mm and 5 mm, preferably in the range between 0.2 mm and 1 mm.

[0042] The adhesive coating 3 is an adhesive compound based on natural or synthetic rubber. In most cases, an acrylate adhesive and in particular a hot-melt adhesive is used. Basically adhesive compounds based on silicone, polyurethane or polyether may also be used. The invention recommends values in the range between about 20 g/m.sup.2 and 300 g/m.sup.2 for the application weights of the adhesive coating 3.

[0043] The adhesive tape 3, 4 provided with the adhesive coating 3 on one face is combined with a overlay strip 5 to form a laminate 3, 4, 5. For this purpose, the one (single) adhesive tape 3, 4 is applied to the overlay strip 5 in the longitudinal extent, defining a first exposed edge band U.sub.1 on at least one of its two longitudinal edges, as shown clearly in the transition from FIG. 1B to FIG. 1C.

[0044] In this operation, the overlay strip 5 that is formed without an adhesive coating, is bonded to the adhesive coating 3 of the adhesive tape 3, 4. This is done in such a way that the single adhesive tape 3, 4 that is coated on one face, is arranged on the outer face 5a of the overlay strip 5 in this example and/or is bonded to the outer face 5a. FIG. 1B then shows the inner face 5b of the overlay strip 5. At any rate, the overlay strip 5 is pressed with its outer face 5a directly on the adhesive coating 3 of the adhesive tape 3, 4 and then adheres to the adhesive coating 3.

[0045] After the overlay strip 5 has been combined with the adhesive tape 3, 4 to form the laminate 3, 4, 5, then according to the invention, the base strip 4 of the adhesive tape 3, 4 is provided with another second adhesive coating 7 on its inner face, i.e., on the face facing away from the overlay strip 5 and/or the adhesive coating 3. Thus, while the overlay strip 5 is provided and arranged on the outer face of the adhesive tape 3, 4, the second adhesive coating 7 is placed on the inner face of the adhesive tape 3, 4.

[0046] It can be seen here that the additional second adhesive coating 7—in addition to the first adhesive coating 3 on the adhesive tape 3, 4—is provided over only a portion of the area of the inner face of the adhesive tape 3, 4.

[0047] To implement this partial-area finishing of the inner face of the base strip 4 of the adhesive tape 3, 4 in detail, the adhesive used on this face can be applied by spraying it onto the inner face, taking into account a mask on the inner face of the base strip 4. In this illustrated embodiment, the additional second adhesive coating 7 is illustrated as being much thicker than the first adhesive coating 3. This deviation in the form of representation serves only to illustrate clearly the production process on the arrangement of the additional second adhesive coating 7. The two adhesive coatings 3, 7 are in fact usually applied to the base strip 4 with comparable application weights per unit of area and/or masses per unit of area. This application weight per unit of area and/or mass per unit of area is usually in the range of 30 g/m.sup.2 to 300 g/m.sup.2.

[0048] As an alternative to this, it is also possible for the adhesive coating 7 to be applied to a transfer film (not shown) and then applied to the inner face of the base strip 4 with the help of the transfer film. Other procedures for applying the adhesive coating 7 to the inner face of the base strip 4 are also covered by the invention, for example, a so-called “kiss coating” or a “curtain coating.” In addition, the adhesive coating 7 can be applied to the inner face of the base strip 4 with the help of the spray coating method mentioned above.

[0049] In a topological sense, the design is such that, on the whole, the adhesive tape 3, 4 with its first adhesive coating 3 is applied to the overlay strip 5 in such way as to define a exposed edge band U.sub.1, U.sub.2 on its two longitudinal edges. In doing so, the orientation is such that the adhesive tape 3, 4 is aligned with the adhesive coating 3 facing outward at the two exposed edge bands U.sub.1 and U.sub.2. The first exposed edge band U.sub.1 is the fixation strip already mentioned in the introduction. However, the second U.sub.2 functions as a closure strip as will be explained in greater detail below.

[0050] On the basis of FIG. 1B in particular, one can see that the two exposed edge bands U.sub.1 and U.sub.2 there have approximately the same widths. In fact, however, the procedure here is usually such that a width ratio of 1:1 to 1:5 prevails between the exposed edge bands U.sub.1 and U.sub.2. In other words, the exposed edge band U.sub.1 and/or the fixation strip corresponding to it is/are definitely narrower than the exposed edge band U.sub.2 and the closure strip belonging to it.

[0051] Furthermore, the adhesive tape 3, 4 on the whole is provided with the width B mentioned above that exceeds the width C of the base strip 5 by an amount equal to the two exposed edge bands U.sub.1, U.sub.2. In other words, within the scope of this illustrated embodiment, the following equation holds:

B=C+U.sub.1+U.sub.2.

[0052] On the basis of FIGS. 1B and 1C, it can be seen that the second adhesive coating 7 is offset toward the first exposed edge band U.sub.1 on the inner face of the base strip 4 with respect to a central plane Z. This offset takes into account the fact that in applying the sheath according to the diagram in FIG. 2, the laminate 3, 4, 5 forms a sheath on the elongated object 2, taking into account more than one revolution, so that no uncovered areas of the elongated object 2 can be observed and the cables enclosed thereby are optimally protected from mechanical influences.

[0053] The second adhesive coating 7 has a width D that corresponds approximately to the width of the second exposed edge band U.sub.2 and/or the closure strip and/or exceeds the width of the exposed edge band U.sub.2 in question. The exposed edge band U.sub.1, U.sub.2 in turn has a width that is designed to be much smaller in comparison with the width B of the adhesive tape. In fact, widths of the exposed edge bands U.sub.1, U.sub.2 that are within the range of 5% to 30% of the width of the adhesive tape are observed here. In other words, the equation is

U.sub.1, U.sub.2≅0.05 to 0.3 B.

[0054] Due to the fact that the adhesive tape 3, 4 is oriented with the adhesive coating 3 facing outward on its two exposed edge bands U.sub.1, U.sub.2, the laminate 3, 4, 5 can be wrapped longitudinally around the elongated object 2 in a particularly simple manner. To this end, the laminate 3, 4, 5 is first secured with the adhesive coating 3 on the first exposed edge band U.sub.1 and/or with the fixation strip on the elongated object 2.

[0055] The sheath is next wrapped longitudinally around the elongated object 2 according to the diagram in FIGS. 1C and/or 2. Finally, the additional second exposed edge band U.sub.2, the fixation strip, is adhesively bonded to the longitudinal wrap produced in this way. In addition, the adhesive coating 3 on the second exposed edge band U.sub.2 comes in contact with the second adhesive coating 7. In this way, a particularly intense bonding is observed because the two adhesive coatings 3, 7 are bonded to one another (cf. FIG. 2).

[0056] FIG. 2 shows how the sheath is wrapped around the elongated object 2, taking into account an almost double longitudinal wrap. This is of course not obligatory. In other words, the scope of the invention includes not only multiple sheaths, as shown here, but also the elongated object 2 may be provided with only a single sheath, for example. However, that is not shown in detail here.

[0057] It is obvious that different total widths of the laminate 3, 4, 5 and also different positions and sizes of the fixation strip and the closure strip can be implemented, depending on the variation in the widths B, C, D and the variation in the exposed edge bands U.sub.1 and U.sub.2. On the whole, total widths of the laminate 3, 4, 5 in the range of about 80 mm to 600 mm can be implemented, so that elongated objects 2 of widely varying diameters can be wrapped in this way. These are of course only examples and are nonrestrictive estimates.