Tape Winding Apparatus

1. Field of the Invention

The present invention relates to an apparatus for winding a tape spirally on a core for insulation or other purposes in the manufacture of an electric wire or cable.

2. Description of the Prior Art

A conventional apparatus for winding two tapes on a core is shown in FIGS. 1 and 2. The apparatus includes a spindle 1 having an axial bore defining a core passage, and supported rotatably on a stand 3 by bearings 2, 2'. A pulley 12 is attached to the spindle, while another pulley 14 is connected to the output shaft of a motor 13. A belt 15 extends between the pulleys to transmit the rotation of the motor to the spindle. A pair of holding shafts 5, 5' are provided symmetrically on the opposite sides of the spindle. A pair of tape reels 4, 4' are rotatably supported on the holding shafts, respectively, by a pair of springs 6, 6' which apply a braking force to the reels, and a pair of nuts 7, 7' holding the springs. The spindle is provided with guide rollers 9, 10 for a tape 8. A core 11 is passed through the axial bore of the spindle. The tape reel 4 carrying a supply of tape 16 is mounted on the holding shaft 5, and the tape is passed around the guide rollers and fastened to the core. If the spindle is rotated and the core is advanced in the direction of an arrow in FIG. 1, the tape is unwound from the supply of tape and wound on the core. The winding mechanism on the opposite side of the spindle is used in the same way.

In the apparatus hereinabove described, the tape reel is rotated about the core to wind the tape spirally on the core. If its rotating speed is increased, a centrifugal force and a wind pressure cause the failure of the tape to be fed smoothly and wound properly on the core. The wind pressure creates a particularly great amount of trouble. As the tape reel is relatively large and constitutes a large resistance to the air, it agitates the ambient air and creates a strong wind if it is rotated at a high speed. This wind renders the movement of the tape unstable, and even causes it to come off the guide rollers if the tape tension is insufficient.

It is an object of this invention to provide an improved tape winding apparatus which can maintain stability in the travel of tape even if it is rotated at a high speed.

The apparatus of this invention essentially comprises a device provided between a tape reel and a core for changing the tension of a tape in such a manner that its tension may be higher in an area close to the tape reel than in an area close to the core, and a wind barrier provided between those two areas. In the area close to the tape reel where a high wind pressure is created, the travel of tape is stabilized by its higher tension. In the area close to the core where the tape has a lower tension, the wind barrier shields the high wind pressure and ensures stability in the travel of the tape so that its tension may be sufficiently low when it is wound on the core.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings.

FIG. 1 is a top plan view, partly in section, of a conventional tape winding apparatus.

FIG. 2 is a front elevational view, partly in section, of the apparatus shown in FIG. 1.

FIG. 3 is a top plan view, partly in section of an apparatus embodying this invention.

FIG. 4 is a front elevational view, partly in section of the apparatus shown in FIG. 3.

FIG. 5 is a side elevational view of the apparatus shown in FIG. 4.

Referring to FIGS. 3 to 5 of the drawings, an apparatus embodying this invention includes various parts which are essentially identical to their counterparts in the conventional appatratus. Those parts, for example, a spindle, tape reels and a mechanism for rotating them, are shown in FIGS. 3 to 5 by the same numerals as in FIGS. 1 and 2.

According to this invention, a disk shaped wind barrier 35 is provided between the tape reels 4 and 4' and that portion of the core 11 at which the tape 8 is wound thereon. The wind barrier 35 is provided with a driven tape takeup roller 20 associated with a pinch roller 37. A belt wheel 21 is connected to the takeup roller 20, and a belt 23 extends between the belt wheel 21 and a belt wheel 22 to drive the takeup roller 20. A block 50 is secured to the spindle 1, and an internally toothed gear ring 27 is rotatably supported about the block 50 by bearings 28. A gear 25 is engaged with the gear 27. A shaft 24 has one end connected to the gear 25 and extends through the wind barrier 35, while the other end of the shaft 24 is connected to the belt wheel 22. A variable speed motor 29 has an output connected by a differential gear box 30, a belt wheel 31 and a belt 32 to a belt wheel formed on the outer periphery of the internally toothed gear ring 27. A belt wheel 53 is secured to the spindle 1 and connected by a belt 34 to a correction shaft drive pulley on the differential gear box 30. The differential gear box 30 maintains constant the difference in rotating speed between the spindle 1 and the gear ring 27, i.e., the ratio between the rotating speed of the gear ring 27 relative to the spindle 1 and the rotating speed of the motor 29. Therefore, it is possible to control the rotating speed of the takeup roller 20 if the rotating speed of the motor 29 is controlled.

The wind barrier 35 is provided with guide rollers 36, 39, 41 and 42. A tension control arm 44 is supported by a bearing ring 45 on the spindle 1, and rotatable in the directions of arrows in FIG. 5. Guide rollers 38 and 40 are secured to the arm 44, and a spring 54 urges the arm 44 in one direction. A gear is formed on the outer periphery of the bearing ring 45, and engaged with a gear 47 to rotate it upon rotation of the arm 44. The gear 47 is connected by a shaft 55 to a displacement detector 46 secured to the spindle 1.

Guide rollers 43 and 48 are provided at the end of the spindle 1, and are adjustable to wind the tape 8 on the core at an appropriate angle.

In operation, the tape 8 is unwound from the tape supply 16, and passed about a guide roller 51 secured to the spindle 1, through a hole in the block 50 and a hole 49 in the wind barrier 35, about a guide roller 36 by which the tape is bent at right angles, and about the takeup roller 20. The tape 8 is firmly held between the takeup roller 20 and the pinch roller 37. The tape 8 extends between the guide rollers 38 and 40 on the tension control arm 44 and the guide rollers 39 and 41 on the wind barrier 35, and about the guide rollers 42, 43, and 48, and is fastened to the core 11. If the spindle 1 is rotated, the tape 8 is wound on the core 11. The output signal of the displacement detector 46 is transmitted through a slip ring 52 to a controller not shown to control the rotating speed of the motor 29 to thereby adjust the rotation of the takeup roller 20.

The apparatus shown in the drawings is so designed as to wind two tapes on the core. The other tape can be wound on the core in a similar way by the mechanisms shown by the same numerals carrying the apostrophes, for example, the tape reel 4'.

In the apparatus described above, the tension of the tape 8 in the area between the tape supply 16 and the takeup roller 20 can be controlled independently of its tension in the area between the takeup roller 20 and the core 11 on which it is wound. In the former area, the braking force applied by the spring 6 to the tape supply 16 maintains a high tension which is, however, lower than the level at which the tape is likely to break. In the latter area, the spring 54 fastened to the control arm 44 maintains a relatively low tension which is required to enable the tape to be wound properly on the core 11.

The high tension of the tape in the area between the tape pad 16 and the takeup roller 20 protects the tape against any influence by a strong wind created by the fast rotation of the tape reel 4 when the spindle 1 is rotated at a high speed. The wind barrier 35 disposed between the tape reel 4 and the takeup roller 20 deflects the strong wind created by the tape reel 4 radially outwardly so that it may not reach the takeup roller 20. The wind created by the tape reel 4 does not exert any influence on the tape in the area between the takeup roll 20 and the core 11 where its tension is low. Thus, the apparatus ensures stability in tape travel and its proper winding on the core at a satisfactorily low tension, even if the spindle is rotated at a high speed.

Although the invention has been described with reference to a preferred embodiment thereof, it is to be understood that modifications or variations may be easily made by anybody of ordinary skill in the art without departing from the scope of this invention which is defined by the appended claims. For example, it would be possible to consider an apparatus for winding a single tape, or three or more tapes. It would be possible to consider a greater number of areas in which the tension of the tape is varied. Moreover, the wind barrier may be of any other shape, for example, cylindrical. The influence of the wind created by the tape reel can also be reduced if the takeup roller is placed at a greater distance from the tape reel.