SPOOL MADE OF A THERMOPLASTIC MATERIAL FOR THE WINDING OF WINDING MATERIAL, AS WELL AS TO A METHOD FOR MANUFACTURING THE SAME

Abstract

A spool for winding strand-shaped material having flange discs (22, 24) with an outer flange surface and an inner flange surface (21, 23) as well as a method for manufacturing the spool. The discs have a central through bore (30) that is surrounded by an annular recess (25) with an annular wall (26) positioned in the inner flange surface. A tubular spool core (10) has front surfaces which are connected in a materially bonded manner to the annular wall (26) inside the annular recess (25) of the flange discs (22, 24), wherein at least one channel (32) is provided next to the annular wall (26) inside the annular recess (25) for receiving liquefied connection material. The spool core (10) has approximately the same diameter as the annular wall (26) inside the annular recess (25).

Claims

1. A spool for winding strand-shaped material, comprising flange discs having an outer flange surface and an inner flange surface, each of which has a central through bore that is surrounded by an annular recess with an annular wall inside the inner flange surface, and a tubular spool core, wherein the spool core comprises a tube, the front surfaces of which are connected in a materially bonded manner to the annular wall inside the annular recess of the flange discs, wherein at least one channel is provided adjacent to the annular wall in the annular recess for receiving liquefied connection material, and wherein the spool core has approximately the same diameter as the annular wall in the annular recess.

2. The spool according to claim 1, wherein the materially bonded connection of the spool core to the annular wall has been formed by means of welding or adhesive bonding.

3. The spool according to claim 1, wherein the spool core is an extruded plastic tube.

4. The spool according to claim 1, wherein the spool core is 150-700 mm long.

5. The spool according to claim 1, wherein the diameter of the spool core is 110 to 500 mm.

6. The spool according to claim 1, wherein the central opening of the flange discs has a diameter of between 55 and 130 mm.

7. A method for manufacturing a constructed spool for winding strand-shaped material made of thermoplastic material comprising: a) providing two flange discs having an outer flange surface and an inner flange surface, each of the discs having a centrally arranged central through bore that is surrounded by an annular recess in the inner flange surface, wherein an annular wall extends inside the annular recess, with at least one channel being formed inside the annular recess adjacent to the annular wall, and with a spool core having approximately the same diameter as the annular wall; b) pressing the spool core onto the annular wall inside the annular recess of the inner flange surface; and c) providing liquefied material in a contact area between the spool core tube and the annular elevation, the liquefied material flowing into the at least one channel, and solidifying the material so as to establish a materially bonded connection between the annular wall and the spool core.

8. The method according to claim 7, wherein temporary liquefying of the material in the contact area is realized by means of welding or solvents.

9. The method according to claim 7, wherein the spool is made of a metal or plastic material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG. 1 shows a perspective exploded view of individual components of a spool;

[0042] FIG. 2 shows a perspective view of an assembled spool;

[0043] FIG. 2A shows a detail of FIG. 2 with a centering notch and winding material passage openings;

[0044] FIG. 3 shows a detail of the inner flange surface with a spool core tube prior to the connection to an annular wall on the annular recess, and an outer channel;

[0045] FIG. 3A shows a detail of a further embodiment of the inner flange surface with the spool core tube prior to the connection to an annular wall on the annular recess, and an outer and an inner channel.

[0046] FIG. 4 shows the detail of FIGS. 3 and 3A after the flange and the core have been welded together;

[0047] FIG. 5 shows an entry opening for winding material inside the spool core tube for fully automated winding systems;

[0048] FIG. 6 shows, in a schematic manner, the starting product of a spool in the longitudinal section;

[0049] FIG. 7 shows, in a schematic manner, the finished spool in the longitudinal section; and

[0050] FIG. 8a-8e show a method for manufacturing a plastic spool according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0051] In the following, exemplary embodiments of the invention are described based on a plastic spool. Of course, the disclosed embodiments are only indicated by way of example and can take on alternative forms. The figures are not necessarily to scale; therefore, some features may be exaggerated or minimized in order to clarify details of individual components. Therefore, specific structural and functional details disclosed herein are not to be interpreted in a limiting manner, but rather merely as a representative basis for instructing a person skilled in the art so that they may apply the invention in different ways. As will be understood by a person skilled in the art, features that are shown and described in any figure can be combined with features that are shown in at least one other figure in order to create exemplary embodiments that are not explicitly shown or described. The shown combinations of features are representative exemplary embodiments for typical applications, and may be desirable for certain applications or implementations.

[0052] In the following, the invention is described in more detail based on the example of a plastic spool. However, it may be realized with any thermoplastic material.

[0053] FIG. 1 shows a perspective view of individual parts of a plastic spool according to the invention, comprising a cylindrical spool core 10, with a flange disc 22 being arranged at its end. As can be seen, the spool core 10 is a tube. This is schematically shown in FIG. 6. The flange disc 22 has a central bore 30 and an annular recess 25 on the flange inner side, having a diameter that substantially corresponds to the spool core-tube.

[0054] FIG. 2 shows an embodiment of a completely assembled spool according to the invention. Winding material passage holes 33such as are shown in the detail drawing of FIG. 2Aas well as, where necessary, a centering notch 27 can be formed in the flange discs 22, 23.

[0055] As is schematically shown in detail in FIG. 3, with respect to the spool core 10, the flange disc 22 is arranged in such a manner with an annular wall 26 inside the annular recess 25 that the spool core front surface rests on the annular wall 26 inside the annular recess 25. In this embodiment, a channel 32 is formed externally adjacent to the annular wall 26, with excess material produced during the welding/boding, such as weld beads, running into this channel 32. In the embodiment of FIG. 3A, channels 32 are formed for the same purpose adjacent to the annular wall 26 inside as well as outside. As shown in detail in FIG. 4, in this embodiment, the annular wall 26 is welded together with the spool core front surfaces, as it is also indicated by the wavy lines in FIG. 7. Here, the welding together was carried out by means of hot plate welding, which is a very reliable and commonly used method. The plastic material that is discharged in the course of this process as weld bead is received in the at least one channel 32 inside the annular recess 25 in the flange 22 adjacent to the annular wall 26. In this manner, the formation of weld beads having a negative effect on the spool function is avoided on the spool core 10. In this manner, an entry opening 31 for winding material (see FIG. 5), for example, for cables, inside of which the beginning of the strand is affixed, is not clogged or narrowed in an uncontrolled way, but remains passable in a barrier-free manner even after the welding/bonding.

[0056] The spool components 22, 24, 10 can be made of plastic material in their entirety. In that case, the annular wall 26 for the spool core 10 can, for example, be formed directly at the flange discs 22, 24, which may for example be realized by means of injection molding.

[0057] The tubular spool cores 10 can be manufactured in the desired length by separating sections of conventional plastic tubes, and can then be connectedpreferably weldedto the annular walls 26 at their front surfaces.

[0058] The spool core 10 that forms the winding core for the winding material can have perforations through which the winding material can be treated from the inner side of the spool core. In this manner, heated air for drying the winding material may be passed through the perforations, for example. A treatment by means of gasses or liquids is also possible.

[0059] Likewise, the flanges 22, 24 can be formed with perforations and thinner sections for the purpose of reducing weight and saving material, as may be seen in FIG. 2. Here, a finished plastic spool is shown in a perspective view, wherein reinforcing ribs and slits in the flanges that serve for weight and material reduction may be clearly seen.

[0060] If the application conditions render it necessary, such spools can also be constructed from metal. In that case, the process steps are to be correspondingly selected and adjusted, as is known to the person skilled in the art.

[0061] A method for manufacturing a welded plastic spool is shown in a schematic manner in FIGS. 8a to 8e. FIG. 8a shows, in a perspective and schematic rendering in longitudinal section, the plastic tube for the spool core 10 and a flange 22 with an annular recess 25 and an annular wall 26 extending therein. In FIG. 8b, the two structural components are pressed onto each other so as to be aligned in such a manner that the annular wall 26 and the spool core tube front surface lie on top of each other, and are subsequently heated until the plastic material begins to flow (FIG. 8d) and is finally liquefied (FIG. 8e), and the flange wall 26 and the plastic tube 10 are welded together in a materially bonded manner, with a solidified material flow/weld bead being formed in the channels 32 of the annular recess 25. As a result of the annular recess 25, the weld bead is substantially flush with the flange surface and does not form an obstruction in the winding space. In this manner, it is possible to create smooth and unobstructed windings up to the flange surface. What is obtained as a result of the materially bonded connection is a connection of the flanges at the spool core having a high tensile strength and loadability.

[0062] Although the invention has been explained in more detail based on exemplary embodiments with plastic parts, the person skilled in the art will be familiar with many variations on these embodiments as a part of their expert knowledge. Thus, the description of the invention is provided merely by way of example, and variations such as they are familiar to a person skilled in the art also fall within the scope of the invention as it is defined by the claims.