[0001] The present invention relates to an automatic, self-centering straightening machine
for a continuous fabric, in particular suitable for being combined in line with textile
finishing machines, or with a printing machine.
[0002] Coupling in line with a fabric finishing machine or printing machine, a weft straightener
aligned according to the axis of the finishing or printing machine, wherein the fabric
unrolled from a feed fabric roll is treated in order to have the picks positioned
perpendicularly to the warp threads, or to verify the alignment of the loops, is known.
[0003] These correction actions determine the side shifting of the fabric inside the finishing
or printing machine which cannot be easily controlled, and involve such an error of
treatment or of printing, as to transversely invade, e.g., during the printing process,
the selvedges of the same fabric, in a direction, or in the other.
[0004] The presently feasible correction interventions allow an adjustment, or registering,
of such errors to be achieved only after a certain time period, with a considerable
waste of fabric, and not always do they reach the prefixed aim, because the corrections
which can be carried out show a poor precision.
[0005] A purpose of the present invention is to provide an automatic, self-centering straightening
machine for a continuous fabric suitable for being coupled in line either with a textile
finishing machine, or with a printing machine, and makes it possible both to rapidly
carry out the correct positioning, controlled instant by instant, of the fabric, maintaining
it in line with the finishing or with the printing, and a correct operating of the
straightening unit.
[0006] A further purpose is to be able to operate on a wide range of fabric widths, without
being obliged to replace the straightening machine, or to operate and carry out mechanical
adjustments of the various components of the straightening unit before beginning the
processing, also as a function of the fact that most times it is necessary to process
the fabric on the finishing machines, and, above all, on the printing machines, in
a out-of-centre position relatively to the axis of the same machines, e.g., to print
a trade name on the selvedges.
[0007] These and other purposes according to the present invention are achieved by providing
an automatic, self-centering straightening machine for a continuous fabric, in particular
suitable for being coupled in line either with textile finishing machines, or with
a printing machine of the type comprising a framework wherein a set of corrector rollers
are located, which correct the diagonal, curved or combined deformations of said continuous
fabric, driven by driving means operatively connected with a plurality of detection
means, for the detection of the position of the picks and/or of the alignment of the
loops, characterized in that said machine is provided with means for the transversal
translation of the framework relatively to the direction of fabric feed, which are
operatively controlled by a computer respectively connected with further detection
means for the detection of opposite positions of the ends of the width of the straightened
and centered fabric which leaves said set of corrector cylinders, said further detection
means being located on opposite sides relatively to a processing axis essentially
corresponding to the axis of said machine framework, so that, by means of said translation
means, said processing axis is set and positioned on command by said computer in a
out-of-centre position relatively to the stationary axis of the textile finishing
or printing machine as a function of the width of said fabric, and said further detection
means act continuously to keep the fabric centered in this new out-of-centre position.
[0008] The structural and functional characteristics and the advantages of an automatic,
self-centering straightening machine according to the present invention shall be better
understood from the following exemplifying, non-limitative disclosure, referred to
the hereto attached drawings, wherein:
Figure 1 is a schematic, longitudinal, sectional elevation view of an automatic machine
according to the invention, positioned upstream the inlet of a partially shown printing
machine;
Figure 2 is a side elevation view of the bottom portion of the machine of Figure 1;
and
Figure 3 is a top plan view of the machine of Figure 1.
[0009] Referring to the figures, a self-centering straightening machine according to the
present invention is generally indicated by the reference numeral 10, and is arranged
to receive a continuous fabric 11, e.g., being unrolled from a roll 12, supported
on a fabric roll holder car 47, and to feed it, through return rollers 13, to a printing
machine 14, or to another textile finishing machine, such as a raising machine, and
so forth, partially shown in Figures 1 and 3.
[0010] The continuous fabric 11, by unrolling from roll 12, comes to the true straightening
machine, which comprises a frame 15, above which a first return roller 16 is located,
said first return roller 16 being supported inside an entry gantry 24, which feeds
the same fabric in a vertical direction, towards an underlying centering device or
means 17.
[0011] The centering device 17 is constituted by three rollers 18 on board of swinging side
support rods or shoulders 19, the one of which is hinged in 20 onto the frame 15,
and the other one of which is rotatably constrained to the stem of a hydraulic cylinder
21, so to act on the lateral shift on the vertical plane, and to be used for aligning
the fabric 11.
[0012] The fabric 11 enters then a straightening unit, generally indicated by the reference
number 22, wherein, besides return rollers 9, provided are, e.g., three corrector
rollers for the diagonal deformations 23, on board of a swinging frame 25 motor-driven
in 26, and two further corrector rollers for the curved deformations 27, individually
motor-driven in 28.
[0013] A plurality of optical reading heads 29, and of relevant projectors 30, as detector
means for the position of the picks, and/or for the alignment of the loops, act on
the fabric two by two, from opposite sides, detecting the deformations thereof relatively
to the correct positions of the picks, or of the loops.
[0014] The fabric 11, then, by passing into an outlet calender 31, comes in correspondence
of further detector means 32 and 33, detecting the opposite positions of the ends
of the width of the straightened fabric 11 under processing which leaves said straightening
unit, which opposite end positions indicate the relative position of the fabric relatively
to a processing axis 35 corresponding to the axis of the framework 15.
[0015] Said processing axis 35 is independent from the fabric 11 being processed, and exactly
as a function of the height, or width, of the fabric, it is located in an out-of-centre
position relatively to a central fixed axis 34 of the printing machine 14. For the
purpose of varying the relative position of the processing axis 35, as referred to
the fixed machine axis 34, the framework 15 is mounted on wheels 36 running along
tracks 37, said tracks 37 being also located transversely relatively to the fabric
feed direction 11, and being constrained to a baseplate, or to the floor, indicated
by the reference numeral 38; the framework 15 interacts with, and is moved by a translational
drive means 39, such as a hydraulic cylinder.
[0016] The straightening machine 10 can hence be shifted relatively to the printing machine
14, in relation to the width of the fabric 11 which is being processed.
[0017] A central computer 40 is equipped with a control keyboard 41, and is operatively
connected with a related display screen 42. Said central computer 40 results furthermore
to be operatively connected, through a set of connection leads, with said hydraulic
translational drive means 39, which is provided with a shift control element 43, such
as an encoder, interacting relatively to a starting stop 44, in correspondence of
which the machine according to the invention processes a fabric having the maximum
width.
[0018] In the hereto figures, a machine according to the invention is shown, during the
automatic processing of an intermediate-width fabric.
[0019] Furthermore, with said central computer 40 a microprocessor 45 is connected, which
is associated with the reading heads 29, and with the drive means 26 and 28 of the
corrector rollers 23 and 27. Furthermore, third detection means 46, similar to those
indicated by the reference numerals 32 and 33, are located in correspondence of the
centering means 17, so to detect the alignment of the fabric 11 and transmit such
information to the central computer 40, so that it can consequently actuate the hydraulic
cylinder 21, determining the correction.
[0020] In this way, with a machine according to the invention, once that a roll 12 of fabric
to be processed 11, having a determined width, is installed on the fabric roll holder
47, according to predetermined fixed positions 48 previously defined exactly as a
function of the various fabric widths, through the keyboard 41, the computer 40 and
the translational drive means 39, the shift is caused of the framework 15, so to position
the processing axis 35, which is also the fabric axis 11, out-of-centre relatively
to the stationary axis 34 of the printing machine 14.
[0021] The fabric 11 is thus located out-of-center inside the printing machine 14, and is
positioned with an edge thereof nearly in correspondence with the side edge of the
same machine. In this position, the further third detection means 46 associated with
the centering device 17 detect, and act according to commands coming from the computer
40 to line-up the fabric 11.
[0022] Advantageously, also the further detection means 32 and 33 detect the opposite transversal
ends of the fabric 11 as said fabric is processed, and can act, always through the
computer 40, to modify the position of the framework 15 by means of the hydraulic
actuator 39.
[0023] Of course, coupled with said detection means 32, 33 and 46, the means act, which
detect the position of the picks and/of the alignment of the loops 29-30, and the
relevant microprocessor 45.
[0024] Thus, above all at the relatively low speeds at which the printing is carried out,
an automatic, out-of-centre control is achieved of the alignment of the fabric inside
the same printing machine.
[0025] Thus, it is possible to print, with an extremely high precision, on the selvedge
located in correspondence of the side edge of the printing machine. Then, it is furthermore
possible, e.g., on the display screen 42, to continuously identify all of the parameters
relating to the fabric being processed, and act, through the control keyboard 41,
to correct any possible faulty parameters.
[0026] According to a preferred, but not limitative, form of practical embodiment of the
present invention, also the fabric roll holder 47 runs on further tracks, and is rigidly
connected with the framework 15, so to be always perfectly aligned, eliminating any
further initial adjustment and positioning of the fabric roll holder 47 relatively
to the fixed positions 48.
1. Automatic, self-centering straightening machine for a continuous fabric, in particular
suitable for being coupled in line either with textile finishing machines, or with
a printing machine of the type comprising a framework wherein a set of corrector rollers
are located, which correct the diagonal, curved or combined deformations of said continuous
fabric, driven by driving means operatively connected with a plurality of detection
means, for the detection of the position of the picks and/or of the alignment of the
loops, characterized in that said machine is provided with means for the transversal
translation of the framework relatively to the direction of fabric feed, which are
operatively controlled by a computer respectively connected with further detection
means for the detection of opposite positions of the end of the width of the straightened
and centered fabric which leaves said set of corrector cylinders, said further detection
means being located on opposite sides relatively to a processing axis essentially
corresponding to the axis of said framework of the machine, so that, by means of said
translation means, said processing axis is set and positioned on command by said computer
in a out-of-centre position relatively to the stationary axis of the textile finishing
or printing machine as a function of the width of said fabric, and said further detection
means act continuously to keep the fabric centered in this new out-of-centre position.
2. Automatic achine according to claim 1, characterized in that furthermore a centering
means, for centering said fabric relatively to said processing axis is provided, said
centering means too being connected with said computer.
3. Automatic machine according to claim 1, characterized in that said drive means
controlling the translation of said framework are respectively tracks transversely
constrained to the inlet of said textile finishing machines, or of a printing machine,
wheels located on, and constrained to, the basis of said framework, and an actuator
means, operatively interacting between said tracks and said framework, so to move
the one relatively to the others, responding to a command given by said computer as
a function of the width of said fabric.
4. Automatic machine according to claim 2, characterized in that said fabric centering
means too is located on said framework, and is equipped with further third detector
means, which act to align and center the fabric in said out-of-centre position, controlling
at least a shift means, which carries out the shifting of said centering means.
5. Automatic machine according to claim 1, characterized in that said drive means
operatively connected with said plurality of means detecting the position of the picks
and/or the alignment of the loops are connected to a microprocessor, it too connected
to said computer.
6. Automatic machine according to claim 1, characterized in that a centering means
is furthermore provided, which carries out the centering of said fabric relatively
to said processing axis, which is also connected with said computer, and is located
on said framework equipped with third detection means, which act to align and center
the fabric in said out-of-centre position, controlling at least a shift means, which
carries out the shifting of said centering means, in that said translational drive
means controlling the translation of said framework are respectively transversely
constrained tracks at the inlet of said textile finishing machines or of a printing
machine, wheels located on, and constrained to, the basis of said framework, and an
actuator operatively interacting between said tracks and said framework, so to move
the one relatively to the others, responding to a command given by said computer as
a function of said width of said fabric, and that said driving means operatively connected
with said plurality of detection means detecting the position of the picks and/or
the alignment of the loops are connected with a microprocessor, it too connected with
said computer.
7. Automatic machine according to claim 6 , characterized in that said central computer
is connected to a control keyboard and is operatively connected with a relevant display
screen.