Device and Method for Thermosetting a Knitted Fabric

20200040502 ยท 2020-02-06

    Inventors

    Cpc classification

    International classification

    Abstract

    A device for thermosetting a knitted fabric includes a first tool half and a second tool half. The first tool half and the second tool half in a closed position enclose a cavity in which the knitted fabric is receivable. Each of the first tool half and the second tool half have a respective shape-imparting effective surface by way of which an external form of the knitted fabric is determinable. The device further includes a heating installation where thermal energy is introducible into the knitted fabric via the heating installation.

    Claims

    1. A device for thermosetting a knitted fabric, comprising: a first tool half; a second tool half; wherein the first tool half and the second tool half in a closed position enclose a cavity in which the knitted fabric is receivable; wherein each of the first tool half and the second tool half have a respective shape-imparting effective surface by way of which an external form of the knitted fabric is determinable; and a heating installation, wherein thermal energy is introducible into the knitted fabric via the heating installation.

    2. The device according to claim 1, wherein the heating installation is a temperature-controllable medium, wherein at least one of the first tool half and the second tool half has an infeed duct, and wherein the temperature-controllable medium is introducible into the knitted fabric via the infeed duct.

    3. The device according to claim 2, wherein at least one of the first tool half and the second tool half has a discharge duct and wherein the temperature-controllable medium is dischargeable from the knitted fabric via the discharge duct.

    4. The device according to claim 2, wherein the temperature-controllable medium is air and/or steam.

    5. The device according to claim 1, wherein the heating installation is a radiator array.

    6. The device according to claim 5, wherein the radiator array is an infrared radiator or an electric radiator.

    7. A method for thermosetting a knitted fabric, comprising the steps of: disposing the knitted fabric on an effective surface of a first tool half of a tool; impinging the knitted fabric via temperature; closing the tool such that a cavity in which the knitted fabric is disposed is generated between the first tool half and a second tool half; opening the tool; and demolding the knitted fabric from the first tool half.

    8. The method according to claim 7, wherein the step of impinging occurs before the step of closing.

    9. The method according to claim 7, wherein the steps of closing and opening occur before the step of impinging.

    10. The method according to claim 7, wherein the step of impinging occurs after the step of closing and while the tool is closed.

    11. The method according to claim 7, wherein the step of impinging comprises flowing a temperature-controlled medium by the knitted fabric.

    12. The method according to claim 11, wherein the temperature-controlled medium is air or steam.

    13. The method according to claim 11, wherein the temperature-controlled medium has a temperature in a range from 90 C. to 170 C.

    14. The method according to claim 7 further comprising the step of actively cooling the knitted fabric once the knitted fabric has reached a predetermined temperature.

    15. The method according to claim 7 further comprising the step of cooling the knitted fabric by introducing a temperature-controlled medium into the cavity via an infeed duct in at least one of the first tool half and the second tool half.

    16. A method for producing a knitted fabric, comprising the steps of: generating a knitted fabric; cleaning the knitted fabric; and thermosetting the knitted fabric by the method according to claim 7.

    17. The method according to claim 16, wherein the knitted fabric is a 3D knitted fabric.

    18. The method according to claim 16, wherein the step of cleaning comprises cleaning by washing in a liquid.

    19. The method according to claim 16 further comprising the step of introducing a compressible intermediate tier between an effective surface of the first tool half or the second tool half and a surface of the knitted fabric.

    20. The method according to claim 16, wherein the knitted fabric includes eyelets knitted into the knitted fabric.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0033] FIG. 1 in an exemplary manner shows a carrier structure;

    [0034] FIG. 2 shows a knitted fabric in the non-shaped state;

    [0035] FIG. 3 shows a thermosetting tool having a knitted fabric disposed therein;

    [0036] FIG. 4 shows a knitted fabric in the shaped state; and

    [0037] FIG. 5 shows a thermosetting tool according to an alternative embodiment.

    DETAILED DESCRIPTION OF THE DRAWINGS

    [0038] FIG. 1 shows in an exemplary manner an instrument panel support 10 which is to serve as the carrier structure 10 in order for the method to be explained. Alternatively to the I-panel support illustrated, all of the cladding parts found in the vehicle interior such as glove boxes, central arm rests, visors, arm rests in the door trim, roof liners, etc., can also serve as a carrier structure 10. The instrument panel support 10 has a surface 10o which is to be laminated with the aid of a textile surface structure. As illustrated in FIG. 1, the surface can relate to only a portion such as, for example, the upper surface of the binnacle of the so-called combination instrument. The surface 10o to be laminated can however also be that part of the surface of the carrier structure 10 that would be visible to a vehicle occupant in the interior of the vehicle. Furthermore alternatively, the surface 10o can also comprise the entire surface of the carrier structure 10, wherein in this instance regions of the carrier structure 10 that are not visible to a vehicle occupant would be laminated.

    [0039] A lateral view of a knitted fabric 11, or of a textile material, respectively, is shown in FIG. 2. The knitted fabric 11, or textile material, respectively, in an exemplary manner is illustrated as a two-dimensional, i.e., flat, web material in a state after the washing of the knitted fabric. Alternatively thereto, the knitted fabric 11 can also be pre-shaped in a three-dimensional manner or be creased.

    [0040] The knitted fabric from FIG. 2 is introduced into a calibration tool which is configured from tool halves 12, 13. The two tool halves 12, 13 conjointly enclose a defined cavity. The knitted fabric 11 is first placed onto the lower tool half 13 and hereby is pulled to the desired shaped. The tool is subsequently closed and the knitted fabric 11 situated therein is brought to a desired temperature. An upper tool half 12, illustrated here as a press ram 12, is applied to the textile knitted structure 11 and the latter is pressed or kept in a desired shape, respectively, on account thereof. The effective face of the upper tool half 12 in this closed position of the tool presses the textile knitted structure 11 against an effective surface of the lower tool half 13. A surface of the textile knitted structure 11 that faces the tool half 12 herein comes into physical contact with the effective face such that the effective face is shape-imparting to the textile knitted structure 11.

    [0041] In order for the knitted fabric 11 to be temperature controlled, hot air is blown into the cavity by way of infeed ducts 14 which are configured, for example, as nozzle bores in the upper tool half 12, and the knitted fabric material is heated to the desired temperature. Instead of hot air, hot steam from a hot-steam generator can also be introduced into the closed tool and the material be heated to the desired temperature. The hot steam has a positive effect on the required thermosetting reactions in the textile. The knitted fabric herein is configured from one or a plurality of yarns which are knitted in a three-dimensional manner. Each of the yarns is configured from a plurality of filaments, wherein at least one of the filament is configured from a plastics material which is capable of melting and which, when impinged by way of temperature, is capable of being transformed to a viscous or doughy state, respectively. The knitted fabric 11 when thermosetting is thus transformed to a desired external shape. The knitted fabric 11 is subsequently impinged by way of the temperature-controlled medium. The filament capable of melting, also referred to as hot-melt adhesive yarn, is fused herein and connected to neighboring filaments of the yarn or else to other yarns. Alternatively to the hot-melt adhesive yarn, other materials such as, for example, fusible films, materials capable of adhesive bonding, and solutions such as acrylate, can also be used for thermosetting the primary yarn. Once the temperature in the knitted fabric is lowered, the material of the yarn originally capable of melting solidifies and thus sets the surrounding filaments such that the knitted fabric memorizes this shape. The knitted fabric after the thermosetting is dimensionally stable to the extent that the knitted fabric restores the shape after any deformation. The shape of the knitted fabric 11 after the thermosetting preferably corresponds to the shape of the surface 10o of the carrier structure 10 onto which the knitted fabric is to be laminated. The medium is discharged again from the knitted fabric 11 by way of discharge ducts 15 in the lower tool half 13, so that a fluid flow of the temperature-controllable medium from the infeed ducts 14 through the cavity into the discharge ducts 15 results.

    [0042] The textile is actively cooled with the aid of cooling nozzles in the upper or the lower tool half and thus remains in the desired shape which is shown in FIG. 4. The cooling medium can be introduced into the cavity by way of the same infeed ducts 14 as the temperature-controllable medium. Alternatively, separate cooling nozzles by way of which the cooling medium is introduced into the cavity in a dedicated manner can also be provided.

    [0043] Different variants are possible in terms of temperature controlling. FIG. 5 shows the process step of heating in an alternative embodiment of the method. Instead of a hot medium, a radiator array 16 is moved into the open cavity above the 3D knitted fabric 11 and heats the material to the desired temperature by way of radiation heat. The tool then closes, wherein the tool halves 12, 13 therebetween enclose the cavity.

    [0044] In a further embodiment (not illustrated) of the device for thermosetting, the cavity enclosed between the tool halves 12, 13 can be configured so as to open on the periphery. The medium introduced by way of the infeed ducts 15 can thus be discharged by way of the peripheral gap.

    [0045] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.