WO2013076154A1

WO2013076154A1 - Garden hose with woven reinforcement

Info

Publication number: WO2013076154A1
Application number: PCT/EP2012/073256
Authority: WO
Inventors: Edmond Wenzel; Timo Grossmann
Original assignee: Gardena Manufacturing Gmbh
Priority date: 2011-11-21
Filing date: 2012-11-21
Publication date: 2013-05-30

Abstract

The invention relates to a garden hose comprising at least two radially superimposed and interconnected cover layers (M1, M2) and a woven reinforcement produced of high-tensile yarn (G1), which woven reinforcement is arranged between a first (M1) and a second (M2) cover layer, the yarn consisting of a yarn material different from that of the cover layers. The yarn (G1) is connected to at least one of the two cover layers (M1, M2) by means of a fixing material (HD).

Description

Garden hose with fabric insert.

The invention relates to a garden hose with fabric insert. For garden hoses, a hose construction of an inner jacket layer and an outer jacket layer and a fabric insert arranged between them is common. Such a structure allows the production of hoses with sufficient for garden applications bursting pressure between 10 bar and 20 bar with high flexibility of the hose at low cost, which is essential for garden hoses as a commodity. First and second cladding layers are usually made of PVC, wherein the materials for the two cladding layers may have different Shore hardnesses. The tubing is produced by the extrusion process, wherein first the inner shell layer is extruded and wound on this or the fabric insert is knitted. In addition, the second cladding layer is extruded, which has contact surfaces with the first cladding layer through the meshes provided in the fabric inlay and forms a close and stable material connection to the first cladding layer at these contact surfaces.

It turns out that such hoses tend to deform after some time, in particular due to frequent pressure load changes and / or longer lasting high water pressures. Especially at elevated service temperature such. B. in prolonged sunlight and the burst pressure threshold can fall sharply. The present invention has for its object to improve the shape stability and bursting over a long period of use in a low-cost garden hose with fabric insert. The invention is described in the independent claim. The dependent claims contain advantageous refinements and developments of the invention.

Surprisingly, the simple measure of the use of a fixing material between the yarn of the fabric insert and at least one of the two cladding layers provides a significant improvement in the dimensional stability of the hose after changing and sustained high pressure loads even at elevated temperatures, including above all temperatures up to about 60 ° C understood , A permanent torsional deformation of the hose can be largely avoided and the expansion of the hose at high pressures is greatly reduced. In addition, surprisingly shows a significant improvement in the clamping connection of the hose end with a connection part, which typically takes place by attaching the inner circumferential surface to a nozzle of the connecting part and radial pressing of retaining claws in the outer surface of the hose. The effect of the fixing material provided according to the invention is likely to be based on an improved fixation of the yarn of the fabric relative to at least one of the two sheath layers and the improved mutual fixation of intersecting sections of the yarn of the fabric, in particular in a preferred embodiment of the fabric insert at least partially as a mesh fabric By fixing the yarn in connection with the points of intersection of the stitches, a particularly permanent fixation of the yarn course in the original position and a high protection against longitudinal displacement of the yarn in its longitudinal course within the fabric are obtained. weave structure. This is especially important at the end of the hose, where the improved fixing of the yarn by the fixing material prevents in particular pulling yarn ends away from the hose end and thereby the fabric structure persists even to the end of the hose and receives the stability of the hose end and its holding force in the connection part ,

A fixing material is generally understood to mean a material which increases the fixing of the yarn of the fabric insert relative to at least one of the two sheath layers. In particular, it is not necessarily presupposed that the fixing material forms a higher surface adhesion of smooth surfaces of yarn material and material of the first or second cladding layer. The improved adhesion of the yarn of the fabric to a cladding layer can also be effected by an improved embedding of the yarn in the fixing material and its firm connection with the material of the cladding layer.

In a first advantageous embodiment, the fixing material may be provided as a surface coating on the yarn of the fabric insert, so that the yarn is already applied to the outer surface of the first layer when applied to the yarn

Sheath layer is completely surrounded by the fixing material. The

Surface coating can be produced, for example, by spraying on the yarn or by soaking the yarn passing through a bath. In another advantageous embodiment, fixing material may be present as an admixture with the material of the yarn. The fixing material may be added in a further advantageous embodiment, the material of the first and / or the second cladding layer.

In another, preferred embodiment, the fixing material can be inserted as at least one planar intermediate layer between the fabric insert and one of the jacket layers. Since, as a rule, the fabric insert between the yarn runs forms openings through the fabric layer, the area fraction of these openings typically occupying the by far largest portion of the surface of the fabric layer, the first and second jacket layers are also directly or optionally interposing a flat intermediate layer via these openings from the fixing material connected to each other.

In a preferred embodiment of the fabric insert in the form of two fabric layers applied radially one above the other, a planar intermediate layer of the fixing material is preferably provided between the two fabric layers. The intermediate layer then forms, with the exception of the punctiform intersections of yarn strands of the first fabric layer with the second fabric layer, both an intermediate layer between the first fabric layer and the second jacket layer and an intermediate layer between the second fabric layer and the first jacket layer and at the same time an intermediate layer in the overlapping regions directly between the first and second cladding layers. Advantageously, a plurality of intermediate layers may be provided from one or different fixing materials, in which case advantageously two radially successive intermediate layers of fixing material enclose a fabric layer between them. A flat intermediate layer can in particular be produced as a further extrusion layer or applied as a band spiral around the underlying fabric layer. Preferably, both the first and second cladding layers consist at least predominantly of inexpensively available PVC (polyvinyl chloride). Advantageously, the fixing material may also consist of PVC. PVC is available in a wide range of Shore hardness, with typically higher Shore hardness material also having a higher softening temperature. In the first advantageous embodiment, a material having a greater Shore hardness than for the first cladding layer can be provided for the second cladding layer. Preferably, the first cladding layer has a higher, in particular by 5-15 Shore hardness higher Shore hardness than the material of the second cladding layer. In a preferred embodiment, the material of the first cladding layer has a hardness of between 75 and 85 Shore and the material of the second cladding layer has a hardness of between 65 and 75 Shore. The fixing material advantageously has a lower softening temperature and thus typically a lower Shore hardness than the first and the second skin layer.

The Shore hardness of the first shell material is advantageously at least 70 Shore. The Shore hardness of the fixing material is advantageously softer by at least 5 degrees of hardness, in particular at least 10 degrees of Shore hardness, than the material of the first and second sheath layers.

The invention is illustrated below with reference to preferred embodiments with reference to the figures still in detail. Showing:

1 a hose cross section,

2 a knitted tubular fabric, 3 is an enlarged surface section of Fig. 1st

4 shows an embodiment with two fixing layers. FIG. 5 shows an embodiment with a double fabric layer and three

Fusing layers.

In Fig. 1 shows a cross section through a hose SC. For the tube is assumed in a conventional manner a circular cross-section. The thickness of the individual layers is not to scale.

The tube contains in a conventional manner a first cladding layer M1, which forms an inner tube around the inner space IR containing during operation. On the outwardly facing side of the first cladding layer M1, a fabric insert made of a tensile yarn GA is arranged, which counteracts an expansion of the inner tube formed by the first cladding layer M1 during operation under pressurized interior IR. The fabric insert is in turn surrounded by a second outer layer forming a second jacket M2, which protects the fabric insert against external damaging influences and which also forms the outer tube surface in the example outlined. The tube SC may also contain, over the jacket layer M2, another liner layer forming the outer surface of the tube or inserts of a different material within the second jacket layer M2.

In the example according to FIG. 2, it is further assumed that between the outwardly facing surface of the first cladding layer M1 and the inner surface of the cladding layer M2 facing the cladding layer M1, an intermediate layer ZS is formed from a fixing material. FIG. 2 shows a simple example of a fabric knitted in helical turns about the longitudinal axis LA of the tube with a continuous yarn thread GA, the illustration being viewed as a development of the layer of the fabric insert into a plane. The stitches of the knitted fabric form openings MO in the fabric layer whose transverse dimensions are typically large in relation to the diameter of the yarn thread GA. In the crossovers of the different stitches attributable sections of the yarn thread GA, the yarn thread undergoes a strong deflection. The knitting direction is inclined by the coiled knitting operation against the longitudinal axis LA. Common fabric layers, which are typically designed as so-called knitted or knitted tricot fabrics, show more complex mesh structures and tighter, sometimes also multiple overlaps and wraps of yarn thread sections.

Fig. 3 shows in various stages of the production of the hose a section of the outside of the inner cladding layer M1 with subsequent components. In Fig. 3 (A), on the outside of the first cladding layer M1, a fabric having one or more yarn yarns G1 is applied, of which yarn yarns only the end surfaces of yarn yarns lying in the sectional plane are shown. The yarn threads are typically slightly pressed into the surface of the first jacket material M1 by the process of winding or knitting this first fabric layer. Mesh openings of the first fabric layer are designated MO1. The yarn threads are shown for simplicity with a circular cross section without dividing into filaments and usually rather flattened. The diameter of the yarn threads in free tension is typically about 0.1 mm. In the tense on the first coat layer applied position yarn threads are further flattened, so that even at thread overlaps the cumulative thicknesses are usually smaller than 0.3 mm. In a next step, a planar intermediate layer of a fixing material HM is deposited by extrusion via the first fabric layer formed by the yarn threads G1. The still plastically soft fixing material HM emerging from the associated extrusion nozzle settles on and around the yarn threads G1 and in the stitch openings MO1 directly onto the outside of the first jacket layer M1. In this case, the material of the fixing layer HM and the material of the first cladding layer M1 are selected such that, upon direct contact of the fixing material HM with the first cladding layer M1, a boundary layer which firmly melts the two materials together is formed. Preferably, the first cladding layer M1 and the fixing layer HM are made of PVC, wherein the PVC material of the fixing layer HM has a lower Shore hardness and a lower softening temperature than the material of the first cladding layer M1. Such differences in the otherwise chemically same material PVC can be predetermined by different average chain lengths in the polymerization or by additions to the PVC material in a conventional manner.

In the next step, a further fabric layer with yarn threads G2 is applied to the outer surface of the fixing layer HM, the first and the second fabric layers preferably being in the form of coiled knit fabrics with mutually opposed helical ends. From the second fabric layer again only the lying in the sectional plane faces of the yarn threads G2 are shown. The mesh openings of the second fabric layer are designated M02. In a next step, the second cladding layer M2 is applied to the second fabric layer by extrusion from a further extrusion die. In the mesh openings MO2, the material of the second cladding layer is applied directly to the fixing material.

The material of the second cladding layer M2 preferably has a higher hardness and a higher softening temperature than the fixing material HM. In this way, it can advantageously be achieved that the fixing material again sufficiently softens and the yarn threads G2 of the second fabric layer are embedded in the fixing material HM and largely enclosed by the latter, whereby the outer surface of the fixing material HM also smoothes and the fixing material forms an intermediate layer ZS between the first Cladding layer M1 and the second cladding layer M2 forms with approximately constant thickness. The mean layer thickness of the intermediate layer ZS is advantageously between 0.5 times and 2 times the diameter of the yarn threads G1, G2. The layer thickness of the intermediate layer ZS is typically in the range between 0.2 mm and 0.6 mm.

Due to the close enclosure of the yarn threads G1, G2 by the fixing material HM in the intermediate layer ZS and the mechanically strong connection between the fixing material HM and the materials of the first cladding layer M1 and the second cladding layer M2 at the respective boundary surfaces, a strong fixation of the yarn threads G1 results , G2 within the intermediate layer ZS also for the case that no strong connection of the different materials takes place at the interfaces between fixing material HM and yarn threads G1, G2. In particular, at the overlapping points of yarn threads with strong deflection of the yarn course, which are mentioned in the description of FIG. 2, a stable anchoring of the yarn yarns results from the close embedding into the fixing material of the intermediate layer ZS. webelage or the fabric layers predetermined and maintained during the hose extrusion.

FIG. 4 shows an exemplary embodiment in which a first layer H1 of a fixing material is deposited on the first cladding layer made of the first material M1 as a layer running around the first cladding layer M1, preferably by extrusion. This layer has a lower softening temperature or lower Shore hardness than the cladding layer M1.

In the next step, a fabric insert G1 is applied to this first fixing layer H1, which burrows deeply into the material of the first fixing layer due to the low hardness of the possibly doughy first fixing layer H1 and thus already largely enclosed by this first fixing layer to a considerable extent or even already can be. Thereafter, a second fixing layer HD is applied to the first fixing layer H1 with the fabric layer G1 as a cover layer, which leads to an additional complete enclosure of the yarn threads of the fabric. The softening temperature or Shore hardness of this second fixing layer HD may be the same as or slightly higher than that of the first fixing layer H1. However, the material of the second fixing layer HD is

advantageously so soft that a complete close enclosure of the yarn threads is ensured. The second fixing layer HD is advantageously so thick together with the first fixing layer H1 that the outwardly facing surface of the second fixing layer HD essentially forms again a smooth lateral surface. As a result, the outer surface of the second fixing layer HD can advantageously be used for receiving an optical structure by printing on the outer surface of the second fixing layer HD or by laminating structured film parts, in particular in strip form. The second cladding layer M2 is then on the second M2 is then deposited on the second fixing layer HD, optionally with the interposition of an optical structure, in a new extrusion step. FIG. 5 shows a further embodiment with a double fabric insert, which combines the procedures according to FIGS. 3 and 4. On the first cladding layer M1, a first fixing layer H1 is applied by extrusion and on this the first fabric layer G1 is applied, which digs deep as described in FIG. 4 in the first fixing layer. A second fixing layer H2 is extruded onto this first fabric layer and the first fixing layer H1, via which layer thereafter the second fabric layer is applied, which burrows into the material of the second fixing layer. Via the second fabric layer, a further fixing layer is extruded analogously to the fixing layer HD as a cover layer, which in turn can form a smooth outer surface to the second jacket layer to be extruded thereafter.

Due to the plurality of fixing layers results in a particularly intimate embedding of the two fabric layers and thus a particularly strong fixation of the yarn threads of the fabric layers.

The features of the various layer structures can also be realized with one another in variants other than those described, wherein, in particular, the fixing layer HD can be dispensed with if a smooth outer surface to the second jacket layer is not required. The production of a fabric layer on a low-hardness fixing layer advantageously already leads to a strong embedding of the yarn threads into the respective fixing layer during the production of the fabric. The features indicated above and in the claims, as well as the features which can be seen in the figures, can be implemented advantageously both individually and in various combinations. The invention is not limited to the exemplary embodiments described, but can be modified in many ways within the scope of expert knowledge.

Claims

claims:

1 . Garden hose (SC) with one of at least two radially successively arranged and interconnected cladding layers (M1, M2) and between a first (M1) and a second (M2) the two cladding layers arranged fabric insert of tensile yarn (GA), from a yarn material different from the cladding layers, characterized in that the yarn (GA, G1, G2) is connected to at least one of the two cladding layers (M1, M2) via a fixing material (HM).

2. Garden hose according to claim 1, characterized in that the first (M1) and the second (M2) cladding layer and the fixing material (HM) at least predominantly consist of a material of the same chemical composition, the fixing material (HM) but one with respect to first (M1) and second (M2) cladding layer has lower softening temperature.

3. garden hose according to claim 2, characterized in that first

(M1) and second (M2) cladding layer and fixing material at least predominantly, preferably completely made of PVC.

4. garden hose according to one of claims 1 to 3, characterized in that the yarn (GA, G1, G2) consists of polyester.

5. garden hose according to one of claims 1 to 4, characterized in that the fixing material is given by a surface coating of the yarn (GA).

6. garden hose according to one of claims 1 to 5, characterized in that the fixing material is added as an admixture in the material of the yarn (GA) of the fabric insert.

7. garden hose according to one of claims 1 to 6, characterized in that the fixing material (HM) by at least one planar intermediate layer (ZS) between the fabric insert (G1, G2) and at least one of the two cladding layers (M1, M2) is given.

8. garden hose according to claim 7, characterized in that the fabric insert formed by two fabric layers (G1, G2) and an intermediate layer (ZS) of the fixing material (HM) is arranged between the two fabric layers.

9. garden hose according to claim 7 or 8, characterized in that the average thickness of the intermediate layer is less than 1 mm, in particular less than 0.5 mm.

10. garden hose according to claim 1 to 9, characterized in that the Shore hardness of the second cladding layer (M2) is higher than the Shore hardness of the first cladding layer (M1).

1 1. Garden hose according to one of claims 1 to 10, characterized in that the Shore hardness of the first cladding layer (M1) is at least 70 Shore.

12. garden hose according to one of claims 1 to 1 1, characterized in that the Shore hardness of the fixing material (HM) by at least 5 Shore hardness levels is less than the Shore hardness of the first cladding layer (M1).

13. garden hose according to one of claims 1 to 12, characterized in that the fabric insert is at least partially formed as a mesh fabric with mesh openings (MO).