[0001] The present invention relates to a weaving loom with a shuttle having an improved
transport system. More particularly, the invention relates to a weaving loom in which
shuttle transport is optimized from the point of view of speed and reliability.
[0002] It is known that weaving looms have suitable shuttles which are meant to carry the
weft thread from one end of the beater of the loom to the other, in order to insert
it between the warp threads so as to allow to weave a fabric.
[0003] This weft thread transport occurs, as mentioned, by means of so-called shuttles,
which are constituted by elongated elements which internally accommodate a bobbin
of thread which unwinds out of the elongated element.
[0004] In order to convey the weft thread from one end of the beater of the loom to the
other, the shuttles must be propelled by means of a suitable mechanism from one end
of the beater to the other. At said ends there are provided suitable drop boxes which
have a plurality of compartments for independently accommodating a plurality of shuttles.
[0005] In practice, the shuttles are propelled, one at a time, from one end of the beater
to the other and are accommodated, in each instance, in different compartments of
the drop boxes.
[0006] In order to move a different shuttle every time, the drop boxes are conveniently
moved vertically with respect to the longitudinal extension of the loom, so that a
different shuttle is placed in front of the reed of the loom each time and is then
accommodated in the corresponding compartment provided in the drop box arranged at
the opposite end with respect to the one from which the shuttle set off.
[0007] In this manner, by using a plurality of shuttles it is possible to carry a plurality
of weft threads from one end of the beater to the other, achieving fast and effective
weaving.
[0008] However, the critical aspect of this solution lies in appropriately moving the different
shuttles from one end of the beater to the other.
[0009] Transport is currently obtained mainly by means of two systems.
[0010] In a first case, the shuttles are propelled from one end of the loom to the other
by means of a suitable lever cam. The cam has an accurately designed profile and is
suitable to strike, during its movement, a lever which trips a second lever which
allows to propel the shuttle from one end of the loom to the other, i.e., from one
drop box to the opposite drop box.
[0011] However, this solution has speed restrictions due to mechanical limitations of the
cam-lever system, in addition to the fact that both the cam and the levers are subject
to intense mechanical wear, consequently reducing the reliability of the entire transport
mechanism.
[0012] Moreover, the shuttles propelled from one end of the beater to the other, through
the warp threads, enter the drop boxes at high speed and the impact inside the drop
box can damage the shuttle itself.
[0013] A second system currently used to transport the shuttles is of the pneumatic type,
in which there is a first piston meant to compress a second nitrogen-driven piston
which, once compressed and following a movement of the first piston, is capable of
releasing the stored energy, pushing the shuttle from one end of the beater of the
loom to the other.
[0014] Also in this case, however, although an improvement in noise terms is achieved with
respect to the cam-and-lever system (said cam-and-lever system is in fact plagued
by a noise problem which sometimes exceeds the maximum allowed threshold), an ideal
solution is still not achieved, since the transport of the shuttles, and therefore
the speed that said shuttles can reach, is limited by the presence of the two actuation
pistons. Moreover, as in the preceding case, it is not easy to control the stroke
of the shuttles.
[0015] Moreover, the drop boxes used in conventional weaving looms must, as mentioned, be
moved vertically with respect to the longitudinal extension of the loom, and this
translatory motion is provided by means of a pair of pistons, accordingly providing
a mixed hydraulic and pneumatic solution.
[0016] This entails drawbacks from the point of view of the travel speed of the drop boxes,
in addition to constructive complexity of the transport mechanism.
[0017] The aim of the present invention is to provide a weaving loom with shuttles having
an improved transport system, in which the shuttles are propelled from one end of
the beater of the loom to the other end with the possibility to accurately adjust
their stroke and at a higher speed than in known solutions.
[0018] Within the scope of this aim, an object of the present invention is to provide a
weaving loom with shuttles having an improved transport system, in which the shuttle
transport mechanism is simpler than conventional mechanisms.
[0019] Another object of the present invention is to provide a weaving loom with shuttles
having an improved transport system, in which the dimensions of the transport mechanism
are reduced considerably with respect to known solutions.
[0020] Another object of the present invention is to provide a weaving loom with shuttles
having an improved transport system, in which the obtainable weaving speed is substantially
higher than the speeds that can be obtained in conventional looms.
[0021] Another object of the present invention is to provide a weaving loom with shuttles
having an improved transport system, in which the life of the transport mechanism
is longer than the life of conventional transport mechanisms.
[0022] Another object of the present invention is to provide a weaving loom with shuttles
having an improved transport system, which is highly reliable, relatively easy to
manufacture and at competitive costs.
[0023] This aim, these objects and others which will become apparent hereinafter are achieved
by a weaving loom with shuttles having an improved transport system, characterized
in that it comprises at least one shuttle which is suitable to perform a translatory
motion through the warp threads of said loom, said at least one shuttle being actuated
with a propelling motion by motorized means which allow to propel the shuttle from
one end of said loom to the other, in order to successively accommodate said shuttle
from a drop box located at one end of said loom to a drop box located at the opposite
end.
[0024] Further characteristics and advantages of the present invention will become apparent
from the following detailed description of a preferred but not exclusive embodiment
of the weaving loom according to the present invention, illustrated only by way of
non-limitative example in the accompanying drawings, wherein:
Figure 1 is a schematic front view of a weaving loom with shuttles having an improved
transport system, according to the present invention;
Figure 2 is a top plan view of the weaving loom of Figure 1; and
Figure 3 is a schematic side view of the weaving loom according to the invention,
shown in Figures 1 and 2.
[0025] With reference to the above figures, the weaving loom according to the present invention,
generally designated by the reference numeral 1, comprises, as known, a beater 2 which
is suitable to perform a pivoting motion about a point 3, in order to open out the
warp threads 4, so as to allow the passage of the shuttles that carry the weft thread
from one end of the beater 2 to the other.
[0026] In Figures 1, 2 and 3, the reference numeral 5 designates the reed of the loom. Figure
1 is a front view of drop boxes 6 which are arranged at the ends of the beater 2 of
the loom and have a plurality of compartments 7 for accommodating a matching number
of shuttles, designated by the reference numeral 8.
[0027] Each shuttle, as explained above, contains a bobbin or spool of weft thread.
[0028] The particularity of the invention consists of the fact that it has, for the transport
of the shuttles 8, motorized means which are conveniently constituted by a linear
motor 9 which is rigidly coupled to the structure of the loom and allows to propel
a shuttle 8 from one end of the beater 2 to the other.
[0029] In particular, a respective linear motor 9 is provided for each one of the drop boxes
6.
[0030] In practice, therefore, the movement of the drop boxes 6 transversely to the stroke
of the shuttles 8 places the respective shuttles 8, accommodated within the compartments
7 of the drop boxes 6, at the linear motor 9, whose slider 10 propels the shuttle
8 from one end of the beater to the other, until the shuttle is accommodated in the
respective compartment 7 provided in the opposite drop box 6.
[0031] The provision of a linear motor 9 to propel the shuttles allows to achieve a much
higher transport speed than known solutions, in addition to the fact of being able
to precisely adjust the stroke of the individual shuttles 8.
[0032] Moreover, the provision of two linear motors which face each other at the opposite
ends of the beater 2 entails that when one of the shuttles 8 is propelled by one linear
motor 9 and arrives at the drop box 6 arranged at the opposite end, the linear motor
9 that is present at such end acts as a braking system, by means of its corresponding
slider 10, and therefore substantially smoothly guides the shuttle 8 into its compartment
7, preventing its violent impact inside the compartment. This is achieved by providing
for a movement of the slider 10 of the linear motor 9 that is opposite with respect
to the linear motor that propels a shuttle.
[0033] In this manner, the slider 10 of the opposite linear motor substantially smoothly
guides the arrival of the shuttle 8 inside the corresponding compartment.
[0034] Each linear motor is constituted by a bar which contains windings through which current
flows; a slider slides on the bar and has magnets arranged on it.
[0035] As shown by Figures 1 to 3, the linear motors 9 are arranged laterally with respect
to the drop boxes and are rigidly coupled to the structure of the loom, while the
drop boxes 6 are provided with suitable movement means which allow them to move vertically
with respect to the longitudinal extension of the loom.
[0036] The movement means of the drop boxes 6 consist of suitable servomotors 12 which are
adapted to actuate a ballscrew 13, which allows the vertical translatory motion of
said drop boxes 6.
[0037] Respective servomotors for the two drop boxes 6 are further provided.
[0038] The vertical translatory motion of the drop boxes 6 thus provided allows to precisely
place the different compartments 7 at the position of the linear motor 9 and therefore
to position the corresponding shuttles 8 at the slider 10 of each linear motor 9.
[0039] In a second preferred embodiment of the invention, the sliders of the linear motors
are constituted by the shuttles themselves. In this manner, optimum movement of the
shuttles is achieved and their stroke is cushioned gently. In this case the shuttles
themselves, which act as sliders, are provided with magnets. The stroke of the shuttles
is braked by way of the Hall effect by the linear motor that lies opposite the one
that propelled the shuttle (slider).
[0040] In summary, therefore, the invention uses at least one linear motor (with a conventional
slider or with a shuttle acting as a slider); preferably, there are two linear motors
arranged at the ends of the loom.
[0041] In another preferred embodiment of the invention, it is possible to provide a number
of linear motors which is equal to the number of the shuttles, which act as their
sliders. In this case, a linear motor is associated with each shuttle (slider) and
moves vertically with the shuttle associated therewith in order to move into the position
for propelling the shuttle (slider).
[0042] In practice it has been observed that the weaving loom according to the invention
fully achieves the intended aim and objects, since it allows to have an optimum transport
of the shuttles with a speed which is higher than obtainable with conventional transport
systems.
[0043] Moreover, the presence of linear motors for propelling the shuttles allows not only
to increase their travel speed but also to accurately control the position of said
shuttles and therefore their stroke.
[0044] The weaving loom thus conceived is susceptible of numerous modifications and variations,
all of which are within the scope of the inventive concept; all the details may furthermore
be replaced with other technically equivalent elements.
[0045] In practice, the materials employed, so long as they are compatible with the specific
use, as well as the dimensions, may be any according to requirements and to the state
of the art.
[0046] The disclosures in Italian Patent Application No. M199A000186 from which this application
claims priority are incorporated herein by reference.
[0047] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A weaving loom with shuttles having an improved transport system, characterized in
that it comprises at least one shuttle which is suitable to perform a translatory
motion through the warp threads of said loom, said at least one shuttle being actuated
with a propelling motion by motorized means which allow to propel the shuttle from
one end of said loom to the other, in order to successively accommodate said shuttle
from a drop box located at one end of said loom to a drop box located at the opposite
end.
2. The weaving loom according to claim 1, characterized in that said motorized means
comprise at least one linear motor provided with a slider.
3. The weaving loom according to claim 2, characterized in that said at least one shuttle
constitutes the slider of said linear motor.
4. The weaving loom according to claim 1, characterized in that it comprises respective
motor means which are arranged laterally to each one of said drop boxes arranged at
opposite ends of said loom.
5. The weaving loom according to claim 2, characterized in that it comprises a plurality
of shuttles and a matching number of linear motors rigidly coupled thereto, said shuttles
constituting the sliders of said linear motors.
6. The weaving loom according to claim 1, characterized in that said motorized means
are rigidly coupled to the structure of said loom.
7. The weaving loom according to claim 1, characterized in that said drop boxes are actuated
by movement means which allow them to perform a vertical translatory motion with respect
to the longitudinal extension of said loom.
8. The weaving loom according to claim 7, characterized in that said means for moving
said drop boxes comprise, for each drop box, a servomotor which is suitable to actuate
a ballscrew.
9. The weaving loom according to claim 8, characterized in that said ballscrew is suitable
to engage said drop box in order to move, in each instance, the shuttles accommodated
in said drop box at said motorized means, in order to propel the corresponding shuffle
from said drop box to the drop box that lies opposite thereto.
10. The weaving loom according to claim 7, characterized in that said movement means for
actuating said drop boxes are rigidly coupled to the structure of said loom.