THERMOPLASTIC HOSE, AND A DEVICE AND A METHOD FOR PRODUCING SUCH A HOSE

Abstract

The present invention relates to a thermoplastic hose, consisting of a flexible hose body (12; 212; 312; 612) and at least one reinforcing element (14; 214; 314; 614), which is arranged helically on the external face of the hose body (12; 212; 312; 612), wherein the at least one reinforcing element (14; 214; 314; 614) is made of an extruded material and is rigidly joined to the external face of the hose body (12; 212; 312; 612) by means of a fusion bond, wherein the hose body (12; 212; 312; 612) is an extruded hose body (12; 212; 312; 612). The invention also relates to a device and a method for producing such a hose.

Claims

1. Hose, comprising a flexible hose body (12; 212; 312; 612) and at least one reinforcing element (14; 214; 314; 614), which is arranged helically on the external face of the hose body (12; 212; 312; 612), wherein the at least one reinforcing element (14; 214; 314; 614) is made of an extruded material and is rigidly joined to the external face of the hose body (12; 212; 312; 612) by means of a fusion bond, characterized in that the hose body (12; 212; 312; 612) is an extruded hose body (12; 212; 312; 612).

2. Hose according to claim 1, characterized in that the inner wall of the hose body (12; 212; 312; 612) is smooth.

3. Hose according to claim 1 or 2, characterized in that the extruded inner hose has a target inner diameter which, in the longitudinal direction of the hose body, exhibits fluctuations in relation to the target diameter which are less than 5%, preferably less than 3%.

4. Hose according to any of the preceding claims, characterized in that the inner wall of the hose body has a corrugation having an irregular wavelength and/or a long-wave wave in the longitudinal direction of the hose.

5. Hose according to any of the preceding claims, characterized in that the inner wall of the hose body has a corrugation having elevations and indentations in the longitudinal direction of the hose, wherein the distance between two adjacent indentations of the hose is greater than the pitch of two coils of the reinforcing element, preferably greater than the pitch of five coils of the reinforcing element.

6. Hose according to any of the preceding claims, characterized in that the at least one reinforcing element (14; 214; 314; 614) has at least one strip-like or thread-like helical element (18; 218; 318).

7. Hose according to any of the preceding claims, characterized in that the at least one reinforcing element (14; 214; 314; 614) has at least two helical elements (18; 218; 318) that are arranged at a distance from one another and are each helically attached to the external face of the hose body (12; 212; 312; 612).

8. Hose according to any of the preceding claims, characterized in that the at least one reinforcing element (14; 214; 314; 614) has a higher rigidity than the hose body (12; 212; 312; 612).

9. Hose according to any of the preceding claims, characterized in that a cover layer (16, 216; 316; 616) is provided, which is provided on the external face of the hose body (12; 212; 312; 612) and covers the hose body and the at least one reinforcing element (14; 214; 314; 614) at least in portions.

10. Hose according to claim 9, characterized in that the cover layer (16, 216; 316; 616) is an extruded material, wherein the cover layer (16, 216; 316; 616) is preferably an extruded hose element or is made of a strip-like material.

11. Hose according to any of the preceding claims, characterized in that at least the hose body (12; 212; 312; 612) and the reinforcing element (14; 214; 314; 614) are each made of a thermoplastic material, in particular of at least one of the materials PVC, TPE, or PP.

12. Device for producing a hose (10; 210; 310; 610) according to any of the preceding claims, characterized in that the device comprises a system unit that can be operated in a continuous process, wherein the system unit has a first extrusion unit for producing a hose body (12; 212; 312; 612) and a second extrusion unit for producing at least one reinforcing element (14; 214; 314; 614), and wherein the second extrusion unit is arranged behind the first extrusion unit in the discharge direction of the hose and has a nozzle rotating about the hose body.

13. Device according to claim 12, characterized in that the second extrusion unit has a stationary extruder and a rotating forming tool having a nozzle or a forming tool having a rotating nozzle.

14. Device according to claim 12 or 13, characterized in that a third extrusion unit is provided, which is arranged behind the second extrusion unit in the discharge direction of the hose (10; 210; 310; 610), wherein the third extrusion unit preferably comprises a hose nozzle or a wide slot nozzle.

15. Device according to claim 13 or 14, characterized in that a heating device is provided, which is arranged behind the third extrusion unit in the discharge direction of the hose (10; 210; 310; 610).

16. Method for producing a hose (10; 210; 310; 610) according to any of the preceding claims, characterized by the following steps: extruding a hose body (12; 212; 312; 612) that does not rotate about its longitudinal axis; extruding at least one strip-like or thread-like reinforcing element (14; 214; 314; 614); helically applying the reinforcing element (14; 214; 314; 614) in the melted state onto the hose body (12; 212; 312; 612).

17. Method according to claim 16, characterized in that the steps of extruding the hose body (12; 212; 312; 612), extruding the at least one strip-like reinforcing element (14; 214; 314; 614), and helically applying the reinforcing element (14; 214; 314; 614) onto the hose body (12; 212; 312; 612) take place in a continuous process.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Preferred embodiments are explained in more detail with reference to the accompanying drawings, in which:

[0043] FIG. 1a-d are a first embodiment of a hose,

[0044] FIG. 2 is a scheme showing the method for producing a hose,

[0045] FIG. 3a-d are a second embodiment of a hose,

[0046] FIG. 4a-d are a third embodiment of a hose,

[0047] FIG. 5 is a cross section through a helical thread according to a first alternative embodiment,

[0048] FIG. 6 is a cross section through a helical thread according to a second alternative embodiment, and

[0049] FIG. 7a-c are a fourth embodiment of a hose.

[0050] Ways to carry out the invention and industrial applicability:

[0051] In FIG. 1a to 1d, a hose 10 is shown according to a first embodiment.

[0052] FIG. 1a is a side view of the different layers of the hose 10. FIGS. 1b and 1c each show a longitudinal section through the hose 10. FIG. 1d shows a cross section through a hose.

[0053] The hose 10 comprises a flexible hose body 12, a helical reinforcing element 14, and a cover layer 16. The diameter of the hose 10 ranges from 2 mm to 70 mm.

[0054] The hose body 12 is an extruded hose body 12 having a predetermined first rigidity. The inner wall and the outer wall of the hose body 12 are smooth and have no seams or joints.

[0055] The hose 10 and in particular the hose body 12 each have a predetermined target inner diameter, with the fluctuations in the inner diameter of the hose body 12 compared to the target diameter in the longitudinal direction of the hose body 12 being less than 5%, preferably less than 3%. Due to the extrusion, these are long-wave fluctuations in the target inner diameter in the longitudinal direction of the hose body. The wavelength of the fluctuations in the target inner diameter is many times larger than the pitch of the coils of the helical reinforcing element 12. While the wavelengths of the fluctuations in the target inner diameter are around 0.5 m to 1.5 m, the pitch of the coils is in the range of around 1 mm to 100 mm.

[0056] The helical reinforcing element 14 consists of four helical threads 18 arranged parallel to one another, the coils of which have a predetermined inclination with respect to the longitudinal axis of the hose 10. The helical reinforcing elements 14 are materially connected to the extruded hose body 12. In particular, the helical threads 18 are connected to the hose body 12 by means of a fusion bond.

[0057] The four helical threads 18 arranged parallel to one another are each arranged at the same distance from one another, so that, as can be seen in FIG. 1d, the helical threads 18 are positioned equidistantly along the circumference of the hose body 12 on the external face of the hose body 12.

[0058] The cross section of each helical thread 18 has an oval basic shape (see FIG. 1c), the helical thread 18 being adapted to the geometry of the hose body 12 at the contact surface with the hose body 12. The helical thread 18 is an extruded, solid helical thread 18.

[0059] The helical reinforcing element 14 has a predetermined second rigidity.

[0060] The rigidity of the reinforcing element 14 is greater than the rigidity of the hose body 12. The rigidity of the reinforcing element 14 is a parameter with the aid of which the kink rigidity or kink resistance of the finished hose 10 can be influenced.

[0061] The cover layer 16 is an extruded hose element, the helical threads 18 being embedded in the cover layer 16. The cover layer 16 has a predetermined third rigidity. The cover layer 16 is connected to the hose body 12 and the reinforcing element by means of a material bond, in particular by means of a fusion bond. The cover layer 16 has a rigidity that is at least less than the rigidity of the helical thread 18.

[0062] The hose body 12, the reinforcing element 14, and the cover layer 16 are made of thermoplastic materials such as TPE, PP, or PVC.

[0063] FIG. 2 shows the basic method steps for producing a hose, such as the hose 10 shown in FIGS. 1a to 1d.

[0064] First of all, the hose body 12 is made in a first extrusion step 100 by means of a first extrusion unit. For this purpose, a hose nozzle is used as a forming tool, so that the hose body can be discharged in a straight line, i.e., without rotating about its own axis, in the discharge direction. The hose body 12 is then cooled in a known manner using a water bath. In a second extrusion step 110, the reinforcing element 14 is applied onto the still warm or not completely cooled hose body 12 using a second extrusion unit. For this purpose, the thermoplastic material of the reinforcing element 14 is melted in the second extrusion unit and, while still in the melted state, reaches the hose body 12 as a thread-like or strip-like material moving in the production direction or discharge direction. In order to achieve a helical coil of the reinforcing element 18 on the hose body 12 that does not rotate about its axis, the second extrusion unit comprises a rotating nozzle that rotates about the hose body 12.

[0065] In a third extrusion step 120, the hose body 12 around which a reinforcing element 14 is coiled reaches a third extrusion unit. This third extrusion unit applies a cover layer 16 onto the hose body 12 and the reinforcing element 14. The hose emerging from the third extrusion unit is pre-assembled, i.e., cut at the required points.

[0066] In the method shown in FIG. 2, the three extrusion steps 100, 110, 120 take place continuously in a system for producing a hose. In other words, there is no type of assembly between the individual extrusion steps 100, 110, 120 in which the hose 10 is severed.

[0067] The system for implementing the method shown in FIG. 2 comprises three extrusion units, each extrusion unit having an extruder having an extruder screw and a forming tool.

[0068] In detail, the system for implementing the method shown in FIG. 2 comprises a first extrusion unit having a nozzle for producing a hose-shaped element, namely a nozzle for producing the hose body, a conveying section, preferably with water cooling, a second extrusion unit, a further conveying section, and a third extrusion unit.

[0069] The second extrusion unit for producing the reinforcing element comprises a stationary extruder and a rotating nozzle, wherein either the nozzle itself rotates about the hose body or the forming tool in which the nozzle is installed rotates about the hose body. The third extrusion unit is an extrusion unit for producing a hose-shaped element. In this case, the hose body provided with the reinforcing element extends through the third extrusion unit.

[0070] As indicated above, in the second extrusion step, an extrusion unit is provided which has a rotating nozzle. The nozzle can have one or more outlets. In the hose shown in FIG. 1a to 1d, a four-outlet nozzle was used to produce the four helical strips arranged parallel to one another.

[0071] After the third extrusion unit in the third extrusion step, a further conveying section can also be provided, which leads to an assembling unit, in particular to a separating device. Optionally, a heating device can also be provided after the third extrusion unit and before the assembling unit, in order to form, for example, an improved fusion bond between the cover layer and the hose body provided with the reinforcing element.

[0072] In an embodiment (not shown) of the method for producing hoses, it is provided that only the first and second extrusion steps 100, 110 take place continuously.

[0073] The corresponding system thus comprises only a first extrusion unit having a nozzle for producing a hose-shaped element such as the hose body, a conveyor line, preferably having water cooling, a second extrusion unit, and preferably a further conveying section, which leads, for example, to an assembling unit, in particular to a separating device.

[0074] This method is particularly suitable for the production of hoses that do not require a cover layer. However, it does not exclude the application of a cover layer.

[0075] In a device corresponding to this method, the third extrusion unit, which provides the preassembled hose body with a cover layer, is located in an additional system separate from the system having the first and second extrusion unit.

[0076] In one embodiment, the third extrusion unit in the separate system can be an extrusion unit that extrudes a hose-shaped element and applies it onto the preassembled hose body. Alternatively, the extrusion unit can comprise a wide slot nozzle and produce a strip of material that is coiled onto the preassembled hose body rotating about the longitudinal axis. In both cases, after the application of the cover layer, a thermal method step can be provided, by means of which the cover layer is connected to the hose body and the reinforcing element by means of a fusion bond.

[0077] The materials should preferably be selected in such a way that, due to the fusion bond, there is a high adhesive strength between the hose body and the reinforcing element and/or the cover layer. If the selected materials do not achieve this adhesive strength, a step for applying an adhesion promoter can be provided both before the second extrusion step 110 and before the third extrusion step 120.

[0078] FIGS. 3a to 3d and 4a to 4d respectively show a second and third embodiment of a hose 210; 310.

[0079] In particular, FIGS. 3a to 3d and 4a to 4d show two different hoses 210; 310 that have eight helical threads 218; 318 instead of four helical threads 18 arranged next to one another shown in the embodiment in FIGS. 1a to 1d.

[0080] The structure of the hose body 212; 312 and the cover layer 216; 316 and the production of the hose 210; 310 do not differ in the embodiments shown in FIGS. 3a to 3d and 4a to 4d from the embodiment shown in FIGS. 1a to 1d.

[0081] The hoses 210; 310 shown in FIGS. 3a to 3d and 4a to 4d thus have eight helical threads 218; 318 that are arranged equidistantly in a cross-sectional plane around the outer circumference of the hose body 212 or 312. The kink resistance of the hoses shown in FIGS. 3a to 3d and 4a to 4d is therefore higher than in the hose 10 shown in FIGS. 1a to 1d due to the higher number of helical threads in a cross-sectional plane.

[0082] The hoses 210; 310 shown in FIGS. 3a to 3d and 4a to 4d differ in each case by the angle of inclination of the helical threads 218; 318 on the hose body 212; 312.

[0083] The distance and inclination of the helical threads 218; 318 can be adjusted via the process parameters such as the extraction or rotation speed of the rotating nozzle.

[0084] The distance and inclination of the helical threads 18; 218; 318 have an influence on the kink resistance or kink resistance of the finished hose 10; 210; 310.

[0085] The geometry of the cross section of the helical threads 18; 218; 318 can be chosen arbitrarily by means of the geometry of the nozzle of the forming tool. Helical threads 18; 218; 318 can thus be provided with a round or square cross section. In addition, the cross section can exhibit both rounded and angular portions.

[0086] FIGS. 5 and 6 show two different geometries of a cross section of a helical thread by way of example.

[0087] The cross section of a helical thread 418 shown in FIG. 5 is triangular. The cross section of the helical thread 518 shown in FIG. 6 is trapezoidal. Otherwise, the hoses shown in FIGS. 5 and 6 do not differ from the hoses 10; 210; 310 previously shown.

[0088] In summary, the flexibility and kink resistance required by the hose 10; 210; 310 can be adjusted by a suitable selection of the rigidity of the individual components such as hose body 12; 212; 312, reinforcing element 14; 214; 314, and cover layer 16; 216; 316.

[0089] The flexibility of the hose body 12; 212; 312 and the flexibility of the cover layer 16; 216; 316 can be adjusted primarily through the choice of material and the determination of the wall thickness of the hose body 12; 212; 312 or the cover layer 16; 216; 316. The thicker the wall thickness of the hose body 112; 212; 312 or the cover layer 16; 216; 316, the stiffer the hose will be.

[0090] The rigidity of the reinforcing element 114; 214; 314 can also be influenced by the choice of material. In addition, the rigidity of the reinforcing element 14; 214; 314 can be set via the number of helical threads, the size and cross-sectional shape of the helical thread, the distance between the helical threads, and the inclination relative to the longitudinal axis of the hose.

[0091] Within the scope of the invention, the reinforcing element can have one or more helical threads. A plurality of helical threads can have the same distance between each other. However, the distance between more than two helical threads can also vary.

[0092] If more than one helical thread is provided, these helical threads can all have the same properties. In an alternative embodiment, the properties of the helical thread, such as mechanical and/or geometric properties, may differ.

[0093] Instead of a thread-like helical element, the use of strip-like helical elements is also provided within the scope of the invention.

[0094] The thermoplastic materials specified above, such as PVC, TPE, or PP, are suitable as the material for the hose. However, the use of other extrudable materials is also conceivable.

[0095] In the embodiment shown in FIGS. 1a to 1d, 3a to 3d and 4a to 4d, the reinforcing elements 14; 214; 314 are embedded in the cover layer 16, 216; 316.

[0096] FIGS. 7a to 7c show an alternative, fourth embodiment of a hose 610.

[0097] In the hose 610 shown in FIGS. 7a to 7c, the cover layer 616 lies on the reinforcing element 614, so that the hose 610 has a corrugated profile on its external face. In this hose 610 as well, the cover layer 616 is materially bonded to the hose body 612 and the reinforcing element 614.

[0098] Although not shown, the cover layer can also be omitted from the hoses described.

[0099] The hoses described are suitable for use as water hoses. Of course, they can also be used to convey any other fluids (liquids and gases).

[0100] It goes without saying that features that have been described within the scope of one embodiment can also be combined with other embodiments.