[0001] This invention relates to a circular loom for continuously producing a double tubular
material for double-layered bags by continuously weaving a tubular and simultaneously
inserting a separately fabric prepared tubular film into the tubular fabric.
[0002] Bags formed from woven fabrics of a plain weave structure utilizing tapes of synthetic
resins, such as polypropylene and polyethylene resins, or synthetic fiber strands,
such as multifilament yarns or cords, as warps and wefts have been widely utilized
for transportation and storage of bulk items such as grain, sugar, fertilizer, and
synthetic resin pellets. This is because these bags are strong and light in weight.
These bags can be made from a tubular fabric produced by using an ordinary power loom.
There has been an increasing tendency, however, to use circular looms having a high
weaving efficiency. Therefore, various developments for the use of circular looms
have been made in Japan and other industrially advanced countries. Representative
examples of such developments are the circular loom disclosed in U.S. Patent No. 3,871,413
and the circular loom manufactured and sold by the British Company, Fairbairn Lawson
Machinery, Ltd.
[0003] Improved bags with inner bags of non-porous materials such as plastic film inserted
inside to form double-layered bags are suitable for accommodating hygroscopic fertilizers,
volatile chemicals, or small size granules. In a conventional process for making such
double-layered bags, a tubular fabric woven by circular loom is cut into individual
pieces having a predetermined length. Each individual piece is sewn or bonded at one
end thereof to form a first bag. A separate tubular film prepared by blown film extrusion
is cut into individual pieces having the same predetermined length. Each individual
piece is sealed at one end to form a second bag. Next, the second bag is manually
inserted inside the first bag.
[0004] In a conventional circular loom, for example, as disclosed in Figure 3 of the U.S.
Patent No. 3,871,413, the central portion of the loom in which an open end of the
tubular fabric on loom resides is substantially blocked off from access due to the
installation of a mounting means for a cam drum and a driving means. Therefore, there
is no space for inserting another material into the tubular fabric. Accordingly, the
conventional process for making double layered bags is a very inefficient one which
needs much labor and time.
[0005] Circular looms are known, however, which can continuously provide a double tubular
material by continuously weaving a tubular fabric and simultaneously inserting a separately
prepared tubular film into the tubular fabric. For example, reference should be made
to West German Patent No. 29 25 553 and Belgian Patent No. 503 229. However, it is
important when inserting the film into the tubular fabric to ensure that the film
is inserted at the same rate as the production of the material without twists and
that the double thickness issuing from the loom is drawn off flat without creasing
or wrinkling of the interior film.
[0006] To this end, it is an object of the present invention to provide a circular loom
which can continuously produce a double tubular material by continuously weaving a
tubular fabric and simultaneously inserting a separately prepared tubular film, characterised
in that guiding means are provided for the tubular film as it is inserted into the
tubular material to ensure that the film is inserted without wrinkles and to constrain
the cross-sectional shape of the film to change from circular to flat as the double
material is drawn off from the loom.
[0007] According to the present invention there is provided a circular loom for producing
double tubular material, in which a plurality of warps are inwardly introduced into
the gap between a pair of outer and inner gauge rings through a plurality of healds
circularly arranged along a periphery of the gauge rings and alternately raised and
lowered to form at least a shed around the gauge rings by shedding motions of the
healds, the shedding motions being derived from rotation of a cam drum supported coaxially
relative to the healds and the gauge rings by means of a supporting mechanism, and
in which a shuttle loaded with a weft runs through the shed, whereby a tubular fabric
is woven from the warps and the weft is drawn out through the gap by means of a drawing-off
mechanism the gauge rings, cam drum and supporting mechanism being of annular shape
whereby a space is formed through the central portion of the circular loom, and an
inner bag material feeding mechanism being provided for continuously inserting a tubular
material utilized as an inner bag into the tubular fabric through the central space,
the circular loom being characterised in that the inner bag feeding mechanism comprises
a guiding means for inner bag material including a circular shaped guiding disc supported
by a plurality of rollers arranged in a circle in such a manner that the supporting
rollers are engageable with a circumference of the guiding disc, and a pair of guide
wheels spaced from the guide disc in the feeding direction of the tubular material,
and both the guiding disc and the guide wheels being connected to a supporting rod
which is provided with a pair of swing arms symmetrically pivoted adjacent the bottom
thereof, the swing arms being connected to each other by a length-adjustable stay
and each carrying one of the guide wheels, the swing arms, the length-adjustable stay
and the guide wheels serving to constrain the cross-sectional shape of the tubular
material from circular at the guiding disc to flat at the drawing-off mechanism.
[0008] The present invention will now be described by way of example, with reference to
the accompanying drawings, in which:
[0009] Figure 1 is a sectional side view illustrating the major parts of a circular loom
according to the present invention; and Figure 2 is a front view illustrating a part
of a guiding means for an inner bag material.
[0010] In Figure 1, a circular loom is depicted comprising a loom body A, for weaving a
tubular fabric utilized for an outer bag material and an inner bag feeding mechanism
B, for supplying a tubular film utilized for an inner bag material. The loom further
comprises creels (not shown), for supplying a plurality of warps to the loom body
A, and a taking-up mechanism for winding up a resultant double tubular material (not
shown).
[0011] The loom body A is provided with a pair of inner and outer gauge rings (1), (2) and
a cam drum (4) with a cam rail (3) on the circumference thereof. Warps (5) are introduced
to the gauge rings (1), (2) from the outer side.
[0012] The cam drum (4) is rotatably supported around an axis (7) of the gauge rings (1),
(2) by means of a supporting mechanism (6). The gauge rings (1), (2), the cam drum
(4), and the supporting mechanism (6) all comprise an annular shape. The supporting
mechanism (6) is provided with a sleeve (8) arranged coaxially to the axis (7) and
a thrust bearing (9) rotatably fitted in an annular groove on the upper surface of
the sleeve (8). An inwardly projected flange (10) provided on the cam drum (4) is
engaged with the aforesaid bearing (9), thereby the cam drum (4) is supported with
the bearing (9) and the flange (10). Further, a plurality of holding rollers (12),
each of which is rotatably mounted at an upper end of supporting rods (11), are engaged
with the flange (10). The bottom ends of the sleeve (8) and of the supporting rods
(11) are fixed on an annular base (14) secured to a table (13).
[0013] The outer gauge ring (2) is supported by connection to uppermost ends of a plurality
of supporting posts (15). The bottom end of supporting posts (15) is secured to the
base (14). The inner gauge ring (1) is also stationarily supported on the base (14)
by connection to a plurality of brackets (16).
[0014] The warps are drawn into a plurality of healds (17), (18) and shed by up-and-down
motion thereof. Each of the healds (17) and (18) is coaxially arranged on a circle
having a predetermined radius around the axis (7). A plurality of cam followers (19)
are engaged to the cam rail (3) of the cam drum (4), and the healds (17) which face
and mate with the corresponding healds (18) are connected to the corresponding cam
followers (19). The cam follower (19) is guided to be displaceable along the up-down
direction by means of a corresponding guide rod (20). The one heald (18) is connected
to the other heald (17) and the cam follower (19) through a belt (22) engaged to a
pulley (21). Accordingly, the healds (17) and (18) are reversely displacable from
one another in the up-down direction.
[0015] Such healds and the up-and-down mechanism thereof are described in detail in the
aforementioned U.S. Patent No. 3,871,413 and in the International Patent Application
PCT/JP 79/00138 (WO 80/01173).
[0016] Wefts are unwound from a plurality of shuttles (23). The shuttles (23) are held between
the shedding warps (5) in a runnable conditions along the outer circumference of the
gauge rings (1) and (2). The shuttles (23) run by thrust of pushing rollers (24) as
hereinafter described. The pushing rollers (24) are rotatably pivoted on brackets
(25) which are equidistantly secured on the upper surface of the cam drum (4).
[0017] Such a shuttle and driving mechanism thereof are described in detail in the afore-mentioned
International Patent Application PCT/JP 79/00138 (WO 80/01173).
[0018] The cam drum (4) is driven by a motor (26). A driving shaft of the motor (26) is
connected to a rotational shaft (29) by means of a pulley (27) and a belt (28). The
rotational shaft (29) is installed parallel to the axis (7) of the gauge rings (1),
(2), and a pinion (30) secured on an upper end of the rotational shaft (29) is intermeshed
with an external ring gear (31) provided on the circumference of the cam drum (4).
[0019] It is a feature of the present invention, as described hereinbefore, that the motor,
shafts and gears are all arranged in a region remote from the axis of the cam drum
and, thereby, a space is provided through the central portion of the loom body A.
[0020] In the present embodiment, the inner bag feeding mechanism B is installed above the
loom body A, in which a roll (32) of a tubular plasticfilm (34) prepared by a blown
film extrusion system is supported by brackets (33) and in which the film (34) unwound
from the roll (32) is guided by a guide roller (35) onto the gauge rings (1) and (2).
[0021] Thereafter, a resultant double tubular material (100) is downwardly dragged by a
delivery roller (37) disposed under the loom body A through a gap between the gauge
rings (1) and (2) to a take- up mechanism (not shown).
[0022] Next, the operation of the above-mentioned apparatus according to the present invention
will be explained.
[0023] The rotation of the driving shaft of the motor (26) is transmitted to the cam drum
(4) through the belt (28), the pinion (30), and the ring gear (31
[0024] The cam drum (4) thereby rotates around the axis (7) of the gauge rings (1) and (2).
The thrust bearing (9) also rotates along the annular groove on the sleeve (8) together
with the rotation of the cam drum (4). The holding roller (12) rotates according to
the rotation of the cam drum (4), thereby the flange (10) is pressed onto the bearing
(9) and is held stably.
[0025] The cam drum (4) causes the cam followers (19) to be alternately displaced in the
up-and-down direction due to the rotation thereof and results in the shedding motion
of the warps (5).
[0026] The pushing rollers (24) rotate together with the cam drum (4) and the brackets (25).
The shuttles (23) thereby run through the shedding warps (5) along the circumference
of the gauge rings (1) and (2) to feed the wefts.
[0027] As a result, a tubular fabric (36) for the outer bag is woven from the warps (5)
and the wefts and is continuously taken out through the gap between the gauge rings
(1) and (2) in the downward direction.
[0028] During the taking-out operation, the tubular film (34) from the guide roller (35)
is inserted into the tubular fabric (36) passing through the interior of the gauge
rings (1), (2) the cam drum (4), and the supporting mechanism (6). The tubular film
(34) thus inserted is drawn out together with the tubular fabric (36) by the delivery
roller (37).
[0029] A point which must be watched during the insertion of the tubular film (34) into
the tubular fabric (36) is that the two tubular material must be advanced at an equal
rate without slippage therebetween and neither of the materials must be wrinkled.
Clearly, the tubular fabric (36) is of a cylindrical shape immediately after being
drawn out from the gap between the gauge rings due to the shape of the gap, but is
gradually flattened in the passage to the delivery roller (37) and increases in width
thereof. Because of this fact, the tubular film (34) to be inserted into the tubular
fabric (36) preferably should undergo a corresponding transformation. According to
the embodiment shown in Figure 1, the above-mentioned transformation is carried out
by means of a guiding means C for the inner bag material provided in the mid-portion
of the feeding passage of the tubular film (34). The guiding means C comprises a guiding
disc (38), which is to be positioned inside of the tubular film (34) above the gauge
rings (1) and (2), and two guide wheels (39) symmetrically arranged at a predetermined
distance at an outer end of a supporting rod (41) extending downwardly from a center
of the disc (38). The disc (38) is formed with the same diameter as that of the tubular
film (34) when stretched out in a tubular form. The two guide wheels (39) are adjusted
to have a maximum distance therebetween corresponding to the width of the tubular
film (34) when lapped flatly. The tubular film (34) unwound from the roll (32) is
advanced downwardly from the guide roller (35) in a flat condition. It is then opened
up into a cylindrical form by means of the guiding disc (38). As it proceeds lower,
it is then gradually widened by the guide wheels (39), and, in the widened condition,
is inserted into the tubular fabric (36), transformed in the same manner. Due to this
process, a double tubular material can be produced having less slippage as well as
less wrinkles in both of the tubular materials.
[0030] In order to maintain the guiding disc (38) stably at a predetermined position, a
plurality of supporting rollers (40) are arranged around the predetermined position
in the mid-portion of the passage of the tubularfilm. The supporting rollers (40)
contact a periphery of the guiding disc (38) and are supported by stands (46) secured
on the stationary part of the loom.
[0031] Figure 2 illustrates the detailed construction of the mounting of the guide wheels
(39). The supporting rod (41) is a hollow tube.
[0032] A shaft (42) is slidably inserted into the interior of the rod (41). At a bottom
portion of the supporting rod (41) are symmetrically pivoted two swing arms (43),
each of which is rotatably provided with the aforesaid respective guide wheel (39)
at one end thereof. Further, perpendicular to the bottom end of the shaft (42) is
fixed a midportion of a stay (44). The ends of the stay (44) are threaded in opposite
directions to each other. From the midportion of the swing arms (43) are projected
bolts (45) with threads of reverse direction to that of the corresponding threads
on the stay (44). The swing arm (43) and the stay (44) are connected together by means
of two known turn-buckles (46), each of which is engaged to the corresponding threads
on the swing arms (43) and the stay (44). Due to such a construction, the two guide
wheels (39) are held at a constant distance therebetween. When changing the distance
between the guide wheels (39) corresponding to a new size of the utilized tubular
film (34), the turn-buckles (46) should be rotated manually in the suitable direction.
[0033] In addition to the above-mentioned construction, the loom according to the present
invention may comprise other mechanisms already adopted in a known circular loom,
such as a dancing lever (47) for adjusting warp tension.
[0034] As described above, according to the present invention, since the gauge rings, the
cam drum, and the supporting mechanism thereof are formed in an annular shape, the
tubular film for the inner bag can be inserted into the tubular fabric for the outer
bag through the space formed in the central portion of the loom body, and thus the
double tubular material can be obtained continuously in one process.
[0035] Further, due to the guiding means, the tubular film for the inner bag can be layered
to the tubular fabric while being changed in shape in a similar manner, thereby allowing
a high quality resultant product to be obtained.
[0036] In the above-mentioned embodiment, the tubular film for the inner bag is supplied
from the top and the product is taken out from the bottom of the loom. However, it
is possible without exceeding the scope of the present invention that the tubular
film is supplied from the bottom and the product is taken out from the top of the
loom. Further, the material for inner bag may be a tubular fabric prepared by another
circular loom or a knitted fabric prepared by a circular knitting machine.
A circular loom for producing double tubular material, in which a plurality of warps
(5) are inwardly introduced into a gap between a pair of outer and inner gauge rings
(1, 2) through a plurality of healds (17, 18) circularly arranged along a periphery
of the gauge rings (1, 2) and alternately raised and lowered to form at least a shed
around the gauge rings (1, 2) by sheeding motions of the healds (17, 18) the shedding
motions being derived from rotation of a cam drum (4) supported coaxially relative
to the healds (17, 18) and the gauge rings (1, 2) by means of a supporting mechanism
(6), ahd in which a shuttle (23) loaded with a weft runs through the shed, whereby
a tubular fabric is woven from the warps (5) and the weft and is drawn out through
the gap by means of a drawing-off mechanism (37) the gauge rings (1, 2), cam drum
(4) and supporting mechanism (6) being of annular shape whereby a space is formed
through the central portion of the circular loom, and an inner bag material feeding
mechanism (35) being provided for continuously inserting a tubular material (34) utilized
as an inner bag into the tubular fabric through the central space, the circular loom
being characterised in that the inner bag feeding mechanism comprises a guiding means
for inner bag material (34) including a circular shaped guiding disc (38) supported
by a plurality of rollers (40) arranged in a circle in such a manner that the supporting
rollers (40) are engageable with a circumference of the guiding disc (38), and a pair
of guide wheels (39) spaced from the guide disc (38) in the feeding direction of the
tubular material (34), and both the guiding disc (38) and the guide wheels (39) being
connected to a supporting rod (41) which is provided with a pair of swing arms (43)
symmetrically pivoted adjacent the bottom thereof, the swing arms- (43) being connected
to each other by a length-adjustable stay (44) and each carrying one of the guide
wheels (39), the swing arms (43), the length-adjustable stay (44) and the guide wheels
(39) serving to constrain the cross-sectional shape of the tubular material from circular
at the guiding disc (38) to flat at the drawing-off mechanism (37).
Rundwebstuhl zur Herstellung von Doppelschlauchmaterial, bei dem eine Vielzahl von
Kettfäden (5) nach innen in einen Spalt zwischen einem Paar von äußeren und inneren
Paßringen (1, 2) durch eine Vielzahl von Schäften (17, 18) eingeführt werden, die
kreisförmig entlang eines Randes der Paßringe (1, 2) angeordnet sind und abwechselnd
angehoben und abgesenkt werden, um wenigstens ein Fach um die Paßringe (1, 2) durch
Fachbildungsbewegungen der Schäfte (17, 18) zu bilden, wobei die Fachbildungsbewegungen
von der Rotation einer Steuertrommel (4) erzeugt werden, die koaxial bezüglich der
Schäfte (17, 18) und der Paßringe (1, 2) mittels einer Lagerungsanordung (6) gelagert
ist, und bei dem ein Schützen (23), der mit einem Schußfaden versehen ist, durch das
Fach läuft, wobei ein Schlauchgewebe aus Kettfäden (5) und Schußfäden gewebt wird
und durch einen Spalt mittels einer Abzugsvorrichtung (37) ausgeführt wird, bei dem
die Paßringe (1, 2), Steuertrommel (4) und die Lagerungsanordnung (6) ringförmig ausgebildet
sind, wobei ein Raum durch den Mittelbereich des Rundwebstuhls gebildet wird, und
bei dem eine Vorrichtung (35) zur Zuführung des Innensackmaterials vorgesehen ist,
die für das kontinuierliche Einsetzen durch den Mittelraum eines Schlauchmaterials
(34), das als Innensack verwendet wird, in das Schlauchgewebe ausgebildet ist, dadurch
gekennzeichnet, daß die Vorrichtung zur Zuführung des Innensackmaterials Führungsmittel
für das Innensackmaterial (34) besitzt, die mit einer kreisförmigen Führungsscheibe
(38), die auf einer Vielzahl von Rollen (40) gelagert ist, die auf einem Kreis derart
angeordnet sind, daß die abstütztenden Rollen (40) am Umfang der Führungsscheibe (38)
anliegen, wobei ein Paar Führungsräder (39) in Zuführrichtung des Schlauchmaterials
(34) mit Abstand von der Führungsscheibe (38) angeordnet sind und die Führunsscheibe
(38) und die Führungsräder (39) mit einer Haltestange (41) verbunden sind, die mit
einem Paar von Schwenkarmen (43) ausgebildet ist, die symmetrisch dem Boden gegenüberliegend
drehbar hieran gelagert sind, wobei die Schwenkarme (43) miteinander durch eine längenverstellbare
Stütze (44) verbunden sind und jeder eines der Führungsräder (39) trägt und wobei
die Schwenkarme (43), die längsverstellbare Stütze (44) und die Führungsräder (39)
dazu dienen, eine Änderung der Querschnittsform des Schlauchmaterials von einer kreisrunden
Form an der Führungsscheibe (38) zu einer ebenen Form an der Abzugsvorrichtung (37)
zu erzeugen.
Métier circulaire destiné à la fabrication d'une matière tubulaire double, dans lequel
plusieurs chaînes (5) sont introduites vers l'intérieure dans un espace délimité entre
deux anneaux (1, 2) externe et interne d'écartement par l'intermédiaire de plusieurs
lisses (17, 18) disposées circulairement à la périphérie des anneaux d'écartement
(1, 2) et levées et baissées en alternance afin qu'elles formant au moins une foule
autour des anneaux d'écartement (1, 2) lors des mouvements de formation de foule des
lisses (17, 18), les mouvements de formation de foule étant obtenus par rotation d'un
tambour (4) de came supporté coaxialement aux lisses (17, 18) et aux anneaux d'écartement
(1, 2) par un mécanisme de support (6) et dans lequel une navette (23) chargée d'un
trame se déplace dans la foule, si bien qu'un étoffe tubulaire est déplace dans la
foule, si bien qu'une étoffe tubulaire est tissée à l'aide des chaînes (5) et de la
trame et est retirée par l'intermédiaire dudit espace à l'aide d'un mécha- nisme d'extraction
(37), es anneaux d'écartment (1, 2), le tambour de came (4) et le mécanisme de support
(6) ayant une forme annulaire si bien qu'un espace est formé dans la partie centrale
du métier circulaire, et un mécanisme d'avance d'une matière se sac interne (35) est
disposé afin qu'il introduise constamment une matière tubulaire (34) utilisée comme
sac interne dans l'étoffe tubulaire (34) utilisée comme sac interne dans l'étoffe
tubulaire par l'intermédiaire de l'espace central, le métier circulaire étant caractérisé
en ce que le mécanisme d'avance de sac interne comporte un dispositif de guidage de
la matière (34) de sac interne, comprenant un disque (38) de guidage de forme circulaire
supporté par plusieurs galets (40) disposés en cercle de manière que les galets de
support (40) puissent coopérer avec la circonférence du disque de guidage (38) et
deux roues de guidage (39) placées à distance du disque de guidage (38) dans la direction
d'avance de la matière tubulaire (34), le disque de guidage (38) et les roues de guidage
(39) étant raccordées à une tige de support (41) qui porte deux bras pivotants (43)
articulés symétriquement à proximité de son extrémité inférieure, les bras pivotants
(43) étant raccordés l'un à l'autre par une entretoise (44) de longueur réglable et
portant chacun l'une des roues de guidage (39), les bras pivotants (43), l'entretois
(44) de longueur réglable et les roues de guideage (39) ayant pour rôle d'obliger
le passage de la configuration de la section de la matière tubulaire d'une forme circulaire
au niveau du disque de guidage (38) à une forme aplatie au niveau du mécanisme d'extraction
(37).