FR2520013A1 - WEAVING MACHINE WITHOUT HIGH SPEED SHUTTLE - Google Patents

Abstract

WEAVING MACHINE WITHOUT SHUTTLE, WITH WEFT PASSAGE DEVICE, ESPECIALLY WITH RIGID NEEDLES. THE DISTANCE A BETWEEN THE FIRST HALF FRAME C, AND THE DISTANCE B BETWEEN THIS FIRST FRAME C AND THE REAR WIRE HOLDER 6, ARE SUCH THAT THE DISTANCE A IS EQUAL OR LESS THAN 75 MM, AND THAT THE RATIO BA IS INCLUDED BETWEEN 12 AND 15, THE THICKNESS OF FRAMES C, C ... BEING EQUAL OR LESS THAN 7MM. THE INVENTION ALLOWS THE MACHINE TO OPERATE AT A MUCH HIGHER RATE THAN CONVENTIONAL MACHINES.

Description

High Speed Shuttleless Weaving Machine The present invention

  relates to the textile industry and, more particularly, to non-shuttle weaving machines in which the weft yarn is inserted into the shed by means of a weft collar consisting of one or two rigid needles (usually two animated needles). opposite reciprocating movements that exchange the wire substantially in the middle of the width), or by a projectile, or by any other devices allowing the weft thread to pass through the crowd The invention is more particularly directed to wide-width weaving machines, weaving at least

cm wide.

  For several years, manufacturers have sought to manufacture machines of this type flying more and more.

quickly, to increase production.

  But we are quickly limited in the increase of the cadences, because the number of stops of the machine per hour, in particular for breaking of thread, increases very quickly when one increases the cadence, which can lead in fact, to a

decreased productivity.

  Chain yarn breaks are partly due to yarn fatigue (alternating elongations, number of elongation cycles undergone by each point of the yarn, wear of the yarns by circulation in the stringers, percussion between the yarns of the two layers forming the crowd at the time of crisscrossing webs) and, for another part, the impact of a moving member, for example a weft insertion needle, against a warp yarn when the crowd is badly opened and that two sons remained hooked one to

  the other at the cross (formation of Y).

  Another cause of incident during high speed weaving is the poor exchange of the weft yarn, to

  the middle of the width, between the needle and the needle

guille of draw.

  We will now recall the essential elements

  a weaving machine of the aforementioned type.

  The warp threads run from the beam, pass on a rear wire roll, then through the eyelets then

  of smooth worn by several frames and / through the peg J 9 ne.

  The weft yarn is inserted into the shed in front of the comb, by the weft passers actuated by their drive mechanism, then the weft yarn thus deposited is packed by the comb against the line of deformation of the already formed fabric.

  So far, all the classic jobs with

  they have a relative arrangement of the control organs of the substantially identical chain, which is derived from that of the shuttle looms. Thus, if we call the distance between the seam line and the first frame, and b the distance between this first frame and the rear wire holder (the distance a + b being the total "depth" of the trade), we see that for all these trades, the ratio is between 5 and 9 approximately, with a depth of -l in the order of 1200 to 1500 mm Conventionally, the distance a between the frame and the first frame is

  between 120 and 250 mm, while the total angle of

  crowd width is usually around 250

  (2 x 120 5) without exceeding 300 (2 x 150), so as not to

  chain warp of elongations 'excessive alternatives'

  sive. These choice of characteristics and dimensions were considered the most advantageous and gave satisfactory results for the typing rates usual so far, for example from about 240 to

300 rounds a minute.

  But as mentioned above, attempts to substantially increase the Q strike rates on such machines led to operational incidents, forcing the machine to stop and reducing or even canceling the expected production benefits. in more detail in what follows on the phenomena that can cause breaks in wire and,

  more generally, operating incidents.

  The invention aims to overcome these disadvantages of conventional weaving machines and to allow them to operate at a rate much higher than until now, for example 400 to 500 strokes / minute, without increasing the average hourly frequency stops, this

  result is obtained, mainly, by means of a

  new relative position of the control organs of the chain.

  The subject of the invention is a shuttle-free weaving machine, in which the warp threads running from the beam pass over a rear tail, then through the eyelets of the rails carried by several frames, then through the teeth of the comb to finally reach the forming line where the fabric is formed, said machine being characterized in that the first frame is disposed at a distance a from the seam and at a distance b from the rear thread carrier such that the ratio b is equal to or greater than 1 O. Preferably, the ratio b mentioned above is of the order

from 12 to 15.

  The depth (a + b) of looms without a turnip

  with rigid needles being approximately fixed by

  construction requirements, as previously indicated.

  It follows that, on a trade in accordance with the

  The depth of the crowd between the line of the cut and the first frame (distance a) is about 2 to 2.5 times shorter than on a conventional needle loom.

and does not exceed about 75 mm.

  The plaintiff arrived at this conclusion

  whereas, thanks to this new relative provision of the control elements of the chain, the fatigue of the warp threads was reduced to a considerable extent at the same time as the other causes of breakage of the threads or

stopping the machine.

  In addition, this new provision makes it

  a wider crowd opening angle than by

  the past, for example between 300 and 350 (2 x 15 to 2 x 17.5).

  It will also be seen in the following that this provision

  The new design makes it possible to reduce the amplitude of the reciprocating displacements and the weight of certain control elements of the chain compared to conventional looms, thanks to which the mechanisms of the loom can function without inconvenience at much higher rates than on the conventional looms. . It has been found that all these isolated advantageous results have a cumulative effect, so that it has become possible, on a loom according to the invention, to make full use of the performances authorized by improved mechanisms for actuating the needles, in particular Such a mechanism has been described in the French patent No. 2,477,586 in the name of the Applicant. Thanks to this cumulative effect, it has been possible to reach the striking rates of approximately 450 to 600 strokes. / minute, instead of 240 to 300 with the machines known so far. The invention will be better understood on reading the

  detailed description that follows and upon reviewing the drawings

  annexed which represent, by way of non-limiting example,

  an embodiment of the invention.

  FIG. 1 is a schematic view showing the main control members of the warp yarns on a needleless shuttle weaving loom. FIG. 2 shows the relative arrangement of these members and the geometry of the warp in a loom according to FIG.

The invention.

  FIG. 3 shows, on the same scale as FIG. 2, the relative disposition of these members and the geometry of the

chain in a classic craft.

  Fig 4 is a diagram showing the elongation of the wires

  chain when the crowd is open.

  FIG. 5 shows the curves of the rate of elongation of the warp yarns as a function of the opening angle of the crowd for different ratios. FIGS. 6 and 7 illustrate the formation of the "Y" respectively on a conventional loom and on a loom according to the invention. Figs 8 and 9 show the layout of the frames respectively on a conventional craft and on a trade

according to the invention.

  Fig. 10 is a front view of an embodiment of

  invention of a craft according to the invention, with insertion of

frame by two rigid needles.

  Figure 11 is a diagram of a functioning cycle

machine.

  FIG. 12 is a schematic view of the control of

  comb in a machine according to the invention.

  FIG. 13 is a schematic partial view of a loom according to the invention, with weft insertion by a

inertial frame pass device.

  In the diagrammatic representation of FIG. 1, we see the chain 2 which runs from the beam 4, passes on the rear wire holder 6, passes through the eyelets 8-8 'carried by the frames C1-C 2, then The weft yarn 12 is deposited in the shed F by a needle 13 and is then compacted by the comb against the seam line 14 from which the formed fabric 16 is wound on a web.

cloth roll holder 18.

  It should be noted that, for the sake of clarity, FIG. 1 is not to scale in the horizontal and vertical directions and only the first frame C 1 and the second frame C 2 which divide chain in two layers -20 ', while the number of frames is usually

much bigger.

  The distance a is that measured between the forming line 14 and the first frame Ci, while the distance

  b is that measured between this first frame C 1 and the holder

rear wire 6.

  FIG. 2 shows, in scale, in the vertical and horizontal direction, the relative arrangement of the control members of the chain in a loom according to the invention in which the ratio a is greater than 10 ab (ratio = 15, in FIG. 2) and in which the angle θ <

  crowd opening is about 35.

  FIG. 3 shows, on the same scale, the arrangement of the same members in a trade known hitherto in which the ratio b is between 5 and 9 (ratio b = 6 in FIG. 3)

  the opening angle 2 D of the shed being about 250.

  In both figures, the depth a + b or a '+ b' of

job is the same.

  By simply examining these two figures, we can see how different the "geometry" of the crowd is, despite the opening angles of the neighboring crowd, and even larger in the

  case of fig 2 This is particularly true if we consider

  dere part of the crowd (indicated hatched) between the shackle and the first frame which is much more "reduced" in fig 2 that in fig 3 Therefore, in what follows, we will use the denomination "reduced crowd" to designate the particular crowd provided for on a craft according to the invention and the name "classical crowd"

  for trades used so far.

  We will now examine the benefits provided by

this crowd reduced.

  One of the causes of breakage of a warp is the fatigue of the thread caused by the alternate elongations that it undergoes because of the movement of rise and fall of the frames. If we call rate of elongation E the ratio between

  length AB of the wire (fig 4) in the middle position (at the cross

  sure) and the length AC + CB when the crowd is at full aperture, it is evident that E depends on, <and on the ratio.

  elongation in the first frame according to the angle of

  The curves 1-2-3 relate to conventional looms having respective ratios b of a, 7 and 9. Curves 4-5-6-7 relate to looms according to the invention respectively having b-ratios. from a

11, 13, 15 and 17.

  So far, in traditional trades, we accept

  The elongation rate was reduced by about 0.40% in the first frame (for example 0.39% with a = 9 and c, (15).

  between 0.20 and 0.30% for the same angle O <(for example

  ple 0.23 with b = 15) or 41% reduction in the elon-

  In this way, a considerable reduction in the fatigue of the warp yarns is achieved. With an angle increased to 1705, the fatigue rate becomes 0.32, which is a further reduction of the o despite an appreciable increase in the opening angle of the yarn. crowd, which is very favorable, as will be seen later, in the case of sons who do not fit well, but who, in the classical

  can not be applied since it increases the elon-

tion (see fig 4).

  Another cause of fatigue is the wear caused by the movement of the wire 20 in the loop eyelet 8-8 'at each movement of the frames Ci, C 2 ** O Indeed, when the wire is undergoing elongation in position crowd, some of this elongation may be offset by a

  lateral flexion of the slats, but if elongation is important

  aunt it is the thread that ends up moving in the eyelet of smooth and this friction produces a wear of the wire, source

a break.

  The elongation and therefore the fatigue of the warp yarns being reduced by virtue of the invention, the wear is thus also reduced by the circulation of the yarn, all the more so as the friction point on the eyelets is closer to one. fixed point (the seam line), so that a point of the wire in contact with a smooth eyelet moves less than in

a classic job.

  These two advantageous results (reduction of the elongation rate and reduction of wear by circulation of the

  lead) have a cumulative effect, not just add-

  because the wire works in more distant conditions

  of his critical fatigue conditions.

  As mentioned in the introduction to the preface

  In other words, another cause of breakage of a warp thread or incomplete insertion of a weft thread is the impact of one of the needles against a thread when the crowd is not "clean". that is to say when some son do not separate, and remain attached to each other, when opening the crowd There is then formation of "Y", as shown in Figures 6 and 7 This phenomenon of formation of Y is accentuated by the presence of several threads in a tooth of the comb and by the use of threads

irregulars that uncross badly.

  FIG. 6 shows the two plies of warp yarns 20-20 ', the cut line 14, the eyelets 8-8' of the slats carried by the first two frames C-02 and the bisector AB of the shed Si two warp threads 21-21 'remain hung together, at the crossing, at the point D, distant from y' of the cut, they form a "Y" (ADC) of maximum angle @ 8 The crowd is not completely loose and the insertion of the weft thread may not be normal, especially if it is made in the DA area of

  the crowd, or in the vicinity of, this one.

  It will be considered that FIG. 6 represents the formation of a "Y" of maximum angle e on a conventional loom with a normal shed (for example where a is of the order of 130 mm) and is shown same scale, in FIG 7 the formation of a "Y" of the same maximum angle e on a loom "reduced crowd" according to the invention (for example where I is of the order of 65 mm with opening of the crowd 2 c <It is understood that, in both cases, Y angles smaller than Q can also be formed, closer to the shaping, in the zone DA, but these Y are less harmful since more distant from the line o is deposited the frame.The two figures 6 and 7 being homothetic (in the ratio 2 to 1) all the triangles are similar on the two figures and we will have

M '= Y

  These theoretical schemes would therefore tend to show that,

  for the same angle 2 c D of opening of the crowd, the phenomenon

  leads to the formation of Y, their maximum opening angle and their number would be identical with a reduced crowd (fig 7) and with a normal crowd (fig 6)

  However, the plaintiff was able to observe this surprising result.

  In practice, the ratio was smaller than the ratio y, that is to say that a crowd reduced to the formation of the Y's is less frequent than with a crowd.

  normal and that the maximum angle e of Y was smaller.

  This surprising observation can come from the fact that the homothety in the ratio 2 to 1 of Figs 6 and 7 indicated above is not perfect because we considered 5 the same wire in both cases, while the wire on the fig 6 should have a diameter double that of fig 7

  and would therefore cling more with his neighbor, since the

  The warp threads are the same in both cases.

  The plaintiff again made another observation

  who can provide an explanation for this surprising result.

  In fact, if one elongates by pulling a length 1 of a given thread, it starts to turn, a part in one direction, a part in the other, if it is irregular; if we reduce this length, it turns much less At a certain moment, it does not turn any more. When the threads turn when they are stretched at the moment of the tilting of the frames, this rotation is all the more important as the crowd is longer It is during this rotation that the yarns cling and form Y This is another reason which proves that a reduced crowd according to the invention (not exceeding about 75 mm for the dimension a ), will be more "clean" and give less birth to Y, than

  classical crowd (for example from 120 to 200 mm).

  Again, this beneficial result has a cumulative effect

  with the advantageous results reported previously.

  the above described phenomenon of "Y" formation, assuming that the crowd opening angles were

  identical in both cases (Figs 6 and 7).

  However, we have seen that it is possible, thanks to the reduced crowd, to increase the opening angle of the crowd, while maintaining a yarn elongation rate much lower than that applied to a classic occupation It is obvious that increasing the opening angle of the crowd will make the formation of Y more difficult and reduce

so still their number.

  So far, reference has only been made to the first heald frame and, in the figures, only for the sake of clarity have the first two frames C 1 C 2 been included, but, as is known, for the embodiment the largest number of contextson needs frames in greater numbers, usually about ten frames,

sometimes 12 to 16.

  On the classic trades, the frames, which are subjected to alternating movements of amplitude quite large,

  have sufficiently large heights, so that to be suf-

  fisely rigid, they always have a thickness

  between 10 and 16 mm, the most common thickness being 12 mm.

  FIG. 8 schematically shows a conventional loom with a normal shed (for example a '= 150 mm) equipped

  a harness with ten frames of 12 mm C -C 2 -C 3 C 9 -C 10.

  1 2 3 "9 l it 2520013 total The entry 2 ve / h of the stacking of the ten frames is therefore 108 mm If we consider the elongation applied to the wire of

  chain 201 o by the tenth C 10 framework (and no longer the elongation

  tion applied to the warp 20 'by the first frame Cl, as so far), we see that for the same angle 2 e $

  crowd, the rate of elongation is more important than

  so, since the distance to 150 mm has become

  a "= a '+ h = 258 mm, because of the thickness of the harness.

  FIG. 9 shows diagrammatically, on the same scale as FIG. 8, a loom according to the invention with 10 frames also, the reduced mass of which can be measured

for example 65 mm.

  The amplitude of the displacements of the frames and the height of the frames being reduced on a loom according to the invention,

  the thickness of the frames can be reduced without inconvenience.

  According to one characteristic of the invention, the frames have a thickness e which does not exceed 7 mm total. In the case of FIG. 9, the center distance / h of the stacking

  of the ten frames is only 63 mm, so that

  The distance between the forming line 14 and the tenth frame 10 is only: a "= a + h = 65 = 63 = 128 mm, instead of 258 mm for the conventional loom shown in Fig. B. Referring to the curves of FIG. 5, for the same same depth of loom (a + b), and for a / angle 2 o <, the elongation rate of the warp yarn at the tenth frame is

  reduced by about 40% compared to a conventional craft.

  Another cause of fatigue and breakage of warp threads is the number of alternating cycles of elongation that every thread's point undergoes, from the moment it leaves

  the beam until it reaches the line of deformation.

  To reduce this fatigue, it is therefore desirable to

reduce this number of cycles.

  In the foregoing, to simplify the comparisons

  Between a conventional loom and a reduced loom machine according to the invention, it has always been assumed that the depth (a + b) of the loom was the same (see FIGS. 2 and 3). , illustrated by

  FIGS. 3 and 8, where a = 150 mm and 9, = 9, the depth

  In a loom according to the invention, it has been seen that the distance a is less than 75 mm (a dimension "" b

  advantageous being 70 mm) and that the ratio a is advantageously

15.

  In this case the depth a + b of the job conforming to

  the invention would be 120 mm, a reduction of 25.3%.

  As a result, the number of alternating cycles of elongation experienced by a point of the thread before being woven is reduced in the case indicated above also by 25.3% compared to what happens on a conventional loom, which further distances the thread from its critical rate of fatigue and reduces the number of breaks There is again an accumulation of

  advantageous results and, preferably, the choice of

  foundry between 900 and 1200 m = n so as to get the best

  compromise between the benefits obtained.

  It could be said that, in a classical profession, it suffices

  to reduce the depth to obtain the same result.

  tat But it is not because in this case, we would increase the rate of elongation suffered by the warp son and we would not reduce the phenomenon of formation of Y We would not find the beneficial results provided by the invention in a loom according to the invention, the opposite alter v native movement of the two pass-through hands can be produced

  by any known mechanism, for example by a conventional mechanism

  said "diamond", but according to a preferred embodiment, which will be described with reference to FIG. 11, using a so-called "balanced cardan circle" mechanism, such as

  that described in French Patent No. 2,477,586.

  The machine of large width (for example equal to or greater than 1 meter 40) shown diagrammatically in FIG. 10 includes a frame 31 which supports a beam 4 of which

  unrolls in any known way the warp threads 2

  flexible is shown at the top of the machine, but it can occupy any other well-known position of

the skilled person.

  The weft threads 12 are unwound from one or more rolls such as 32 placed outside the machine. The weft threads are inserted, in a known manner, into

  two needles 13-13 ', each running a movement

  alternatively the maximum elongation leads the clamps 33-33 'substantially in the middle of the width The weft thread brought by the needle 13 is then taken by the needle

  13 'which makes him go through the second half of the crowd.

  When the two needles 13 and 13 'have come out

  laughter of the crowd, the comb 10 driven by the swinging 34 cup the newly inserted pick against the line of

  forming the fabric 16 which wraps around the roll 18.

  The movement of each of the needles 13-13 'is

  mandé by a mechanism 35-35 'describing a gimbal circle and communicating with the corresponding needle a sinusoidal movement. Such a mechanism, when it is made according to the above-mentioned patent, makes it possible to actuate the needles, with secure exchange of the weft thread, at a rate of approximately 450 to 600 strokes.

  But in the classical professions, the mass and the am-

  movement of moving parts (especially the comb, leaf and frames) prevents

  correct operation at such rates.

  On the contrary, in a weaving machine according to the invention, as seen above, the frames have a reduced stroke of about half (see Figs 8 and 9) and their weight is much lower, since their thickness does not exceed 7 mm instead of 12 mm on average on a traditional loom. In addition, it is possible to use

shorter, therefore less heavy.

  N The height of the comb, therefore its weight, is also reduced by about half and its stroke, at the bisector of the crowd, does not exceed about 50 mm (44 mm for a distance of 65 mm) instead of 100 mm

about a classic craft.

  It is therefore clear that all the moving parts

  alternatively the machine can operate at a

  rate much higher than conventional machines.

  FIG. 11 shows the different phases of a weaving cycle during which the mechanism -35 'for actuating the needles describes the circumference Y, as it is known in E, the clamps 33-33' '.

  needles 13-13 'exchange the frame in the middle of the width.

  Between E and F, the needles 13-13 'emerge in such a way that in F the clamps 33-33' have reached the edges of the width, then continue to retreat to G Then they start in the opposite direction and the Needle 13 grasps the yarn 12 at about H just before entering the crowd, and transports it to the middle of the width where the gripper 33 reaches E. In the FGH sector, the needles are completely,

  out of the crowd and it is during this period that

  combs and at least part of the movement.

  elements to change the crowd, so that the

  crowd is fully open when the needles enter

  trent again in the crowd (point H).

  On the classic needle looms, the FGH bow

  approximately 1200 (1/3 of the cycle) because the inertia of the

  The comb and the flapper, as well as that of the frames, prevent the duration of the strike being reduced. Therefore, only 2/3 of the cycle can be devoted to the useful stroke of the needles inside the crowd (240 However, in a loom according to the invention, the inertia of the reciprocating members (comb, flapping frames) is much lower and it is possible to operate these organs on a much smaller arc of cycle of the machine, for example 900 or 1000 only for

the movement of the wing.

  This reduction provides many additional benefits.

  According to the invention, if it is assumed, as shown in FIG. 11, that the duration of the striking is reduced to the arc F'GH '(about 9 OW), the clamps 33-33' will be able to reach the edges of the width at F 'and the recoil of the needles will continue only during the arc F'G Thus the needles will stop to turn back to a weaker distance from the edge of the width, which will diminish the overall width of the

  machine (the IG segment is reduced to G).

  In addition, the speed of the gripper 33 animated by a movement

  The sinusoidal is proportional to the sine of the angle -

  This speed is therefore greater in H than in HI If the setting of weft yarn 12 by the gripper 33 is made in H ', the shock received by the yarn 12 will be smaller, so the

risk of breakage will be reduced.

  Finally, needles 13-13 'will benefit from an increased cycle time (260 to 270 instead of 240) for the portion

useful of their race in the crowd.

  Of course, such a modification of the fabric cycle

  wise causes a change in the control of the movements of the leaf If this command is performed by cam (and against-cam), as shown schematically in FIG 12, the boss 38 of the cam 40 of the control comb 10 will extend over an arc less than or equal to 100, by

example 90

162520013

  In the foregoing, mention has especially been made of weaving machines in which the weft device

  consists of rigid needles animated by a

alternatively.

  But the invention also applies to machines in which the frame is inserted by other types of

  devices, for example projectile or "inertia".

  FIG. 13 shows schematically a part of a loom according to the invention in which the frame is inserted by means of a so-called "inertia" system, for example of the type described in the French patent.

No. 2,477,587.

  It suffices to recall that, in such a system, the pick to be inserted forms a loop of which one strand is held and the other free This is accelerated to a speed

  data which communicates to the wire a proportional kinetic energy

  This kinetic energy is used to propel

  close the loop through the crowd; the loop is moving

  gressively until: the end of the free end has

  reaches the edge opposite to the launch side.

  In FIG. 13, only the two warp yarns 20-20 ', the shed F, the seam line 14 and the produced fabric 16 have been shown. The inertial launching system can essentially comprise: a delivery device 41 the pick 12 in an accumulation member 42; insertion rollers 43; a turntable 44 provided with

pliers 45-46; and a knife 47.

  The duet is launched, in a loop, in the crowd F,

by the throwing rollers 43.

Claims (5)

  1 shuttle-free weaving machine with pass-on device   weft, in which the warp threads (2) passing from the beam 4 pass on a rear thread carrier (6), then through the eyelets (8, 8 ') of the rails carried by several frames Ci, C 2 then through the teeth of the comb (10) to finally reach the forming line (4) where the fabric 16 is formed, said machine being characterized in that: the first frame C 1 is disposed at a distance a from the shaping line (% 4) and at a distance b from the rear wire holder (6) such that the distance a is equal to or less than 75 mm, and the ratio b / a is between 12 and 15; and in that the thickness of the frames Ci, C 2, is equal to or less at 7 mm.   Machine according to Claim 1, characterized   in that the width of the width is at least 140 cm.   Machine according to one of claims 1 or 2,   characterized in that the weft device comprises two needles (13-13 '), each of which is actuated, according to a sinusoidal reciprocating movement, by a mechanism   (35-35 ') to balanced Cardan circle.   4 Machine according to one of claims 1 to 3,   characterized in that the depth a + b of the machine is between 900 and 1200 mm.   Machine according to one of Claims 1 to 4,   characterized in that the cams (40) controlling the movements of the flapper of the comb 10 have a profile such that their boss (38) extends over an angle less than or equal to 100 .   Machine according to one of claims 1 or 2,   characterized in that the raster device is a   so-called "inertia" system (41-42-43-44-45-46).