EP0306808A1

EP0306808A1 - Reel for sewing threads with axially movable flange to retain the free end of the thread

Info

Publication number: EP0306808A1
Application number: EP88114123A
Authority: EP
Inventors: Angelo Radice
Original assignee: CUCIRINI TRE STELLE MANIFATTURA DI SETTALA SpA
Current assignee: CUCIRINI TRE STELLE MANIFATTURA DI SETTALA SpA
Priority date: 1987-09-11
Filing date: 1988-08-30
Publication date: 1989-03-15
Also published as: IT8721879A0; IT1222640B

Abstract

The present invention concerns a reel for sewing threads, of the type comprising a cylindrical body (1) having at one end a widened base (2) and a flange collar (3) close to said base. The widened base has an inner rim (2a) surrounding the cylindrical body, to which it is fixed through a plurality of breakable staples (4). Once the thread has been wound, some turns are wound between the flange and the widened base, this latter is then pressed towards the flange causing the breakage of the staples (4) and the fitting of the base into a saw-toothed rib (5) provided on the cylindrical body (1). In this way, the widened base remains in close contact with the flange and guarantees, thanks to the resiliency of this latter, a reliable means of thread retention during the automatic packaging of the reel and during use thereof.

Description

The object of the present invention is a reel for yarns, and particularly for sewing threads, which comprises a structure particularly suited to retain the free end of the thread in a firm and reliable manner.
There are already known to be reels for threads provided with means for retaining the end of the thread. Such retention means are designed to allow a reliable engagement of the thread end, so as to prevent an accidental unwinding of said end during the reel packaging operations. Said requirement is particularly felt, as known, in the field of yarns partly formed with synthetic fibres, having a certain stiffness and elasticity of their own which favours the tendency of the yarn end to unwind.
Reels provided with means for retaining the thread end are known, for example, from the Italian Utility Model No. 156.815 of 3.3.1972, and from the European Patent application No. 85106273.7 of 22.5.1985, both in the name of the same Applicant. These retention means comprise - in association to at least one of the ends of the cylindrical body forming the reel - a widened base and an annular collar, shortly spaced one from the other, between these two elements there being formed a groove, having a wedge-shaped cross section, suited to retain an end of the thread. Preferably, moreover, said groove between the base and the collar comprises opposed radial ribs, apt to improve even further the thread retention effect.
In spite of these improvements, the known retention means of reels are still not fully satisfactory. In particular, it has been found that said retention means are not apt to positively check the free end of the thread, during handling of the wound reels and especially during the banding, cartoning and packaging operations in general, of the reels, with automatic machines. In such machines, it is in fact sufficient for a few reels to have the thread end not correctly checked, to compromise the good result of the automatic packaging operations, and to anyhow require the constant supervision of the plant by costly labour.
The object of the present invention is therefore to realize a reel for yarns, apt to solve this problem and to thus provide for a perfect retention of the thread end, both during use of the reel and, above all, during packaging thereof with automatic machines. This result is obtained by means of a reel for yarns, particularly sewing threads, of the type comprising a cylindrical body, onto which the thread is wound and, at least at one end thereof, a widened base and a flange collar close to said base, between the base and the collar there being formed a groove for housing and retaining the thread end, characterized in that said widened base comprises an inner rim surrounding the cylindrical body at a short distance, in that at least one breakable staple is provided between said inner rim of the base and said cylindrical body, forming an element of connection between the base and the cylindrical body, and in that, onto the surface of said body there is formed, between said base and said collar, an annular rib with toothed profile, the outer radius of which is wider than that of said inner rim.
Further characteristics and advantages of the reel structure according to the invention will anyhow be more evident from the following detailed description of a preferred embodiment thereof, illustrated by way of example on the accompanying drawings, in which:

Fig. 1 is an axial section view of the reel according to the invention, before its use,
Fig. 2 is a similar axial section view of the reel, after its use in an automatic winding machine, and
Fig. 3 is a plan view, from the bottom, of the same reel in the position of figure 1.

As clearly shown in the drawings, the reel according to the invention is formed of a main cylindrical body 1, onto which is wound the thread. At least at one of its ends the body 1 comprises a widened base 2 and a flange collar 3. The thread is wound onto the body 1 for a thickness corresponding to the radial dimension of the collar 3 and of the base 2, as indicated by the dashed and dotted line F in figure 2.
According to the invention, the base 2 has a central hole delimited by an inner rim 2a, which surrounds the body 1 at a short distance. Between the body 1 and the rim 2a there are provided radial tip-shaped staples 4 - shown more clearly in figure 3 - which form an element connecting the base 2 with the body 1. The staples 4 have a small cross section, so as to be easily breakable.
Always according to the invention, onto the cylindrical surface of the body 1, in a position interposed between the base 2 and the collar 3, there is formed an annular rib 5 with a saw-toothed profile, the outer radius of which is wider than the radius of the inner rim 2a. The saw-toothed profile faces with its beveled surface the rim 2a of the base 2.
The reel according to the invention is used in the following manner: once the thread has been wound - during production, for example on automatic winding machines - the free terminal end of the thread is positioned between the base 2 and the collar 3, whereon the thread is wound for a few more turns. Then, a presser of the winding machine - marked by line P in figure 2 - is released by pressure against the base 2. The pressure S of the presser P is sufficient to break the staples 4; the base 2 thus moves towards the collar 3, against which it presses.
During this movement, and also thanks to the flexure of the collar 3, which is made of sufficiently thin plastic material as to be elastic, the base 2 moves beyond the rib 5, by sliding of the rim 2a over the beveled surface of the saw-toothed profile. The opposed portion of said saw-toothed profile then forms an abutment to stop and retain said rim 2a, so that the base 2 is firmly held against the collar 3.
Thus, between the base and the collar, also the previously interposed free terminal end of the thread is held in a perfectly firm manner, so that the automatic packaging operations can be carried out without the slightest hindrance and without requiring any supervising labour.
Moreover, during use, the thread can be removed with no particular difficulties from this position of retention which, furthermore, can continue to be benefited by during normal use of the reel thread.
It is anyhow understood that the invention should not be considered as limited to the particular embodiment described and illustrated, but that there may be other variants differing from the same, particularly for what concerns the number, shape and positioning of the breakable staples, as well as the profile of the saw-toothed rib, and the shape of the base and of the collar, without thereby departing from the scope of the invention itself.

Claims

1) Reel for yarns, particularly sewing threads, of the type comprising a cylindrical body, onto which the thread is wound and, at least at one end thereof, a widened base and a flange collar close to said base, between the base and the collar there being formed a groove for housing and retaining the thread end, characterized in that said widened base comprises an inner rim surrounding the cylindrical body at a short distance, in that at least one breakable staple is provided between said inner rim of the base and said cylindrical body, forming an element of connection between the base and the cylindrical body, and in that, onto the surface of said body there is formed, between said base and said collar, an annular rib with toothed profile, the outer radius of which is wider than that of said inner rim.

2) Reel as in claim 1), providing for a plurality of breakable staples, evenly distributed along the contour of said inner rim of the base.

3) Reel as in claim 1), wherein said annular rib has a saw-toothed profile, the beveled surface of which faces towards said base, and the straight surface of which forms a radial abutment for the inner rim of said base, when this latter is moved to a position of use by breaking the breakable staples.

4) Reel as in claim 3), wherein the axial distance between said radial abutment and said collar is substantially equal to the thickness of said inner rim of the base.