[0001] The present invention relates to an improved rack, or creel, for supplying bundles
of ribbon-like fibres to textile machines such as drawing frames, lapping machines
and any similar machine.
[0002] In racks of a known type for supplying bundles of ribbon-like fibres, from container
boxes, various problems often arise which create torsional stress and lengthening
of the ribbons of fibres and, therefore, a worsening of the quality of the finished
product. The said irregularities are extremely damaging particularly in tops, as experts
in the field well know. As the bundles of ribbon-like fibres are conveyed to the entry
of the work unit they are completely exposed to the dusty environment, which is typical
of the preparation for spinning and thus their final textile properties are negatively
affected by such exposure.
[0003] In racks of a known type, for example those for supplying the drawing rolls of vertical,
or horizontal, drawing frames, the bundles of ribbon-like fibres, from the various
boxes placed side by side, one to the other, are made to pass through the supply pulleys
of the idler rollers and drive rollers, which are driven by the machine head. The
said organs are mounted on a frame for lifting and transferring the bundle of fibres,
which changes the direction of conveyance several times passing from a horizontal
to an oblique direction, or to a vertical direction and vice versa, until entering
the drawing rolls of the drawing frame.
[0004] Despite all the possible mechanical arrangements, the following problems arise:
- on the way from the storage box to the rolls, the bundle of ribbon-like fibres undergoes,
due to stress, various distortions, which may alter the quality of the finished product;
furthermore, as stated, it is completely exposed to the dusty environment;
- great difficulties are encountered in the unfortunately frequent case of ribbons with
a high humidity. In such a case the bundle of fibres often breaks during its movement.
Some boxes, especially those near the rack, are accessed with difficulty by the service
operator who must restore the continuity of the ribbon.
[0005] Machine stoppages which last too long and are too numerous result, thus giving rise
to loss of production; besides this the bundle of fibres is faulty due to the presence
of joins which cause irregularities in the quality of the thread as a final product.
[0006] According to a more improved technique, applied especially in the racks of drawing
frames and lapping-machines, the bundles of fibres are supported, during their journey,
by stationary boards; i.e. by fixed surfaces.
[0007] While some of the above-listed problems may be regarded as overcome, the substantial
problem remains whereby the bundles of ribbon-like fibres, along the said boards,
which lead to the machine, undergo various stresses as a result of friction and, therefore,
undergo appreciable distortions. In order to eliminate, or substantially reduce, the
above-mentioned problems the present invention proposes an improved rack used in textile
machines for supplying bundles of ribbon-like fibres, extracted from collection boxes,
in which the said rack has at least one lifting and transfer track comprising endless
flexible belts moved, one above the other, in the same direction and with the same
value of motion and the said flexible belts are far enough apart to receive, with
suitable compression, the bundle of ribbon-like fibres in order to convey it without
any alteration to the rotating comb head or in any event to the entry of the work
unit.
[0008] The present invention also proposes that the endless flexible belt track, for lifting
and moving the bundle of ribbon-like fibres, has its bottom conveyor branch deformed
in an essentially concave shape, due to the effect of the compression action of the
bundle of fibres, which forces the section of flexible belt below onto a rigid fixed
support below of an essentially concave shape in order sufficiently to envelop the
bundle of fibres, guiding the latter in a perfect sideways position towards the entry
to the rotating comb head. Furthermore, the endless flexible belts of the improved
rack covered by the present invention have a roughness suited to the type of fibre
being supplied and, moreover, the circumferential surface of the drive rollers, which
operate the flexible belts, have sufficient roughness to prevent even the slightest
slipping of the flexible belts as they are driven round.
[0009] With reference to the above, the attached drawings show a preferred embodiment, which
is neither binding nor limiting as regards the reciprocal position of the components
and as regards the consequent simplifications which could arise therefrom; the said
embodiment shall be described below with reference to the following Figures:
- Fig. 1 is a schematic side overall view of a vertical drawing frame including a pre-drawing
module with the supply of bundles of ribbon-like fibres extracted from collection
boxes and where the said bundles of fibre, joined and pre-drawn, are conveyed in a
lifting and transfer track to the comb head, by means of several endless flexible
belts appropriately positioned and moved, as is schematically illustrated in the Figure
together with the collection box below;
- Figure 2 is a schematic side overall view of a vertical drawing frame including a
self-regulator of the bundle of fibres joined with several bundles of fibres extracted
from collection boxes and where the said bundle of fibres is conveyed in a lifting
and transfer track to the comb head by means of several flexible endless belts advantageously
positioned and moved, as is schematically illustrated in the Figure together with
the collection box below;
- Fig. 3 is a cross-sectional schematic view along Line A-A of Figs. 1 and 2 of the
flexible-belt lifting track with the bundle of fibres present and sufficiently compressed
between the facing branches of the said flexible belts, and whose bottom conveyor
branch is deformed in an essentially concave shape to guide the bundle of fibres in
a perfect sideways position to the entry of the rotating comb head.
[0010] In the Figures the same elements, or elements which have the same or equivalent functions,
bear the same reference numbers. In the Figures:
1 is the bundle of fibres positioned and sufficiently compressed between the branches
of the flexible belts, to convey it and transfer it to rotating comb head 7 with the
precise aim of not subjecting it to even the slightest lengthening, or to stress which
causes distortions which affect the quality of the finished product; 2 is the collection
box of the bundle of fibres below distributor plate 4; 3 is the bundle of fibres extracted
from box 5 below and the said bundle of fibres 3, joined with the other bundles of
fibres extracted from the other boxes, supplies the drawing frame; 6 is the top inclined
flexible belt for vertically lifting the bundle of fibres 1, which must be conveyed
from above to rotating comb head 7; 8 is the drive roller which entrains the flexible
belt and the said roller 8 is operated by motor 20; 9 is the horizontal position top
flexible belt; 10 is the creel, or top part of the rack for pulling up the ribbons
by means of a series of unwinding pulleys and drive cylinders, which are driven by
head 18; 12 is the bottom flexible belt with one section in vertical elevation and
one section in a horizontal position. The passage from one position to another occurs
by means of transmission rollers 15; 14 is a pre-drawing module which helps to make
the bundles of fibres 3 joined together uniform and homogeneous; 16 is the self-regulator
device usually present in first-passage drawing frames; 21 is the rigid fixed support
below the flexible branch of the endless belt, and the said fixed support 21 has an
essentially concave shape.
[0011] The operation of the device covered by the present invention, illustrated in the
attached Figures, is easily understood.
[0012] The bundles of fibres 3 extracted from container boxes 5 are joined together to produce
a uniform, homogeneous bundle of fibres with the fibres properly extended and essentially
parallel.
[0013] Once joined together, the bundles of fibres 3 pass through pre-drawing module 14,
or through self-regulator device 16, to be conveyed as a single bundle of fibres 1
to the entry of the drawing unit and rotating comb head 7. Entrainment of the bundle
of fibres 1 should present no so-called "false drawing" to which bundles of fibres
may be subjected. Incidentally, "false drawing" is that lengthening which materials
that are easily deformed undergo, during their transfer onto textile machines, due
to the effect of excessive tension or friction. The important arrangement of the present
invention enables the bundle of fibres 1, once introduced between the facing branches
of flexible belts 6, 12 and 9, to be accompanied, with sufficient pressure and perfectly
guided sideways, to the vertical work unit without being subjected to lengthening
distortion between the point of entry and the point of exit from the said flexible
branches.
[0014] Clearly, variants, modifications and additions may be made by experts within the
field to the constructional details without going beyond the general concept of the
present invention.
1. An improved textile machinery rack for supplying bundles of ribbon-like fibres, extracted
from collection boxes, characterised in that they have at least one lifting and transfer
track comprising endless flexible belts, moved, one above the other, in the same direction
and with the same value of motion and the said flexible belts are far enough apart
to receive, with suitable compression, the bundle of ribbon-like fibres in order to
convey it, without any alteration, to the rotating comb head or in any event to the
entry of the work unit.
2. An improved textile machinery rack, according to Claim 1, characterised in that the
endless flexible belt track, has its bottom conveyor branch deformed in an essentially
concave shape, due to the effect of the compression action of the bundle of fibres,
which forces the section of flexible belt below onto a rigid fixed support below of
an essentially concave shape in order sufficiently to envelop the bundle of fibres,
guiding the latter in a perfect sideways position towards the entry to the rotating
comb head.
3. An improved machine textile rack according to Claim 1, characterised in that the endless
flexible belts, which convey and guide the bundle of ribbon-like fibres, have surfaces
with a roughness suited to the type of fibres being supplied.
4. An improved machine textile rack, according to Claim 1, characterised in that the
circumferential surface of the front rollers, which operates the individual flexible
belt, is roughened.