FR2505805A1 - Stop device for moving fabric web - where defined transverse line coincides with fixed reference line - Google Patents

Abstract

A moving web of fabric is stopped in a certain position when a defined transverse line on the fabric coincides with a fixed reference line, which is generally at right angles to the fabric movement. Where the defined line does not coincide with the reference line, the fabric is allowed to run on. Where separate fabric elements intended for cutting are marked in a continuous run by absence of the weft yarn, surveillance is kept for places where the warp yarns remaining coincide with the fixed reference line, so that a cut is not made in the wrong place. Similarly, where a colour change takes place in the run, or a metallised thread is inserted as a marker, concurrence of the fixed reference line is monitored.

Description

 Method for stopping a strip of fabric in position and installations for implementing the method.

 The invention relates to a method for stopping a strip in position.

 Cutting or making operations, which must be practical on strips of fabric, require very great precision, often difficult to obtain due to the deformability of certain fabrics (especially knitted fabrics).

 The object of the invention is to be able to stop a strip which runs so as to cause a defined transverse line on the strip to coincide with a fixed reference line; the latter being generally a straight line.

 This object is achieved according to the invention, because> i monitors a plurality of longitudi najas sections of the strip which passes, and, when, in a given section, the transverse line defined on the strip coincides with the line fixed reference, immobilize the section give, while continuing to scroll ~ the sections for which the transverse line is not yet in coincidence with the reference line.

 Although it is possible to immobilize a section of the strip of fabric by means of pressure, for example, it is preferred, according to the invention, to immobilize a section of the strip by immobilizing elements, in the form of needles, fingers, or combs, for example, which pass through the fabric.

 This is particularly advantageous in the case where the fabric strip is composed of upstream downstream of at least a first and a second fabric element separated by an intermediate zone of flesh yarns without weft yarns, the downstream edge of the first element constituting the transverse line defined on the strip, because then, we use, both to monitor and immobilize each longitudinal section of the strip, a comb applied to the strip in movement so that it rests and slides on the surface of the second element when the latter passes in front of the comb, and crosses the fabric when the intermediate zone passes in front of the comb, whereby the downstream edge of the first element abuts against the comb which immobilizes the corresponding section. 'is to say that the method of the invention applies in particular to the cutting of the pillows ser in a band with mops.

 But of course, the invention is not limited to this particular aspect of the process. This is how the transverse line defined on the strip can mark the separation between two regions of different colors t one detects the arrival and coincidence, in a given longitudinal section of the transverse line and the reference line pir an optical detector associated with each section, which detection leads to the immobilization of the corresponding section by penetration of a comb into the fabric or any other blocking means. Instead of different colors, wires with metallic fibers can be used, detected by electromagnetic detectors.

 The reference line on which the transverse line defined on the fabric strip must stop is not necessarily a straight line: the stop combs (or the other locking elements provided) can be mounted so that they form a curve of determined profile, which makes it possible to stop in a controlled position elements of fabric separated by a curved line, corresponding to the determined profile.

 The invention also relates to an installation for driving a strip implementing the method of the invention in the case where the strip of fabric is made upstream downstream of at least a first and a second elements of fabric separated by an intermediate zone of warp threads without weft threads, the downstream edge of the first element constituting the transverse line defined on the strip. This installation is characterized in that it comprises a) a stop device consisting of a plurality of combs aligned on the reference line: b) means for adjusting the respective arrangement of the combs and of the strip so that, when the second element passes in front of a comb, the latter slides on the surface of the second element by leaning on it, and when the intermediate zone passes in front of the comb, it crosses the fabric; and c) means for driving the strip capable of driving, when one or more longitudinal sections of strip are immobilized by the other sections.

 This particularity required for the drive means is satisfied if the means comprise, downstream of the combs, a friction drive or, a plurality of drive devices independent of each other controlling the individual drive of each section and controlled penetration of the combs.

 In order to be able to repeat the operation with another intermediate zone, means are provided for releasing all of the combs from the fabric, which makes it possible to advance the strip again.

 According to a first embodiment, the installation comprises means for guiding the strip in a plane in the region of the combs, the stop device consists of a plurality of combs capable of pivoting independently around a same transverse axis and angularly recalled so that each comb presses by sliding on the surface of the second element of fabric when the latter passes in front of the comb and crosses the fabric when the intermediate zone scrolls, taking an angular position of immobilization limited by a stop.

 According to a second embodiment, the installation comprises means for guiding the strip in a plane in the region of the combs, and the stop device consists of a plurality of combs mounted on bent levers articulated on axes parallel to the direction of movement of the strip and angularly recalled so that each comb presses by sliding on the surface of the second fabric element when the latter passes in front of the comb and crosses the fabric when the intermediate zone scrolls taking a position angular immobilization limited by a stop.

 According to a third embodiment, the installation comprises means for guiding the strip consisting of two parallel deflection rollers on the one hand, and combs of the stop device on the other which are fixed on a transverse bar between the two rollers and protrude on one side of the plane of the rollers so that the second element scrolls over the combs at an angle, whereby, when the second element of the fabric scrolls past a comb, the latter presses by sliding on the surface of the element, and when the intermediate zone scrolls past a comb, it enters the fabric.

The invention will be better understood from the description which will be given thereof, with reference to the appended drawings in which
FIG. 1 represents a portion of a strip of fabric used in the exemplary embodiments of the invention which will be described,
FIG. 2 is a perspective view of the device for stopping a first embodiment of an installation according to the invention,
FIG. 3 represents a partial section of the installation of FIG. 2,
FIGS. 4A, 4B, 4C are similar to FIG. 3 and represent three stages in the operation of the installation,
FIGS. SA, SB, 5C, 5D show in plan the installation of FIGS. 3 and 4 at four successive stages of its operation,
FIGS. 6 and 6A represent, in perspective and in schematic section, a second embodiment of an installation according to the invention,
- Figure 7 shows, in schematic perspective, a third embodiment of an installation according to the invention.

 Figure I shows a strip of fabric 1 traveling in the direction 2 and composed of upstream downstream of a first fabric element 3 and a second fabric element 4 separated by an intermediate zone 5 of yarns of caTn b without weft thread 7.

 We try to stop the strip 1 which runs, so that the downstream edge 8 of the first element 3 stops precisely along a reference line (generally a straight line) whatever the deformation of this edge 8. The deformation is not shown in FIG. 1 but is shown, however, in an exaggerated manner in FIGS. 5, 6 and 7.

 According to a first embodiment (FIGS. 2 to 5) the stop device 100 consists of a plurality of combs 101 each fixed on a socket 102 which can pivot independently around an axis 103 arranged transversely in the direction 2 of tape scrolling 1.

 These combs 101 are formed by thin fingers 104, the end 105 of which can be rounded as shown in FIG. 2; the fingers 104 may also have the shape of the fingers which will be described for the other embodiments. The shape of this end is such that the comb cannot penetrate into the fabric 4 under the effect of moderate pressure but on the contrary slides therein, and that it easily penetrates into the intermediate zone 5.

 The combs 101 are angularly recalled to the vertical position by a torsion spring 106 (FIG. 2); each comb can be locked in the vertical position by a finger 107 elastically pushed so as to be able to reengage in a locking groove 108 of the sleeve 102 (FIGS. 3 and 4).

 The strip of fabric 1 moves in a plane on the fingers 104 of the combs 101, driven by means comprising, downstream of the stop device, a drive of the friction type or sectional drive.

In the latter case, the sectional drive is slaved to the penetration of the combs so that certain sections of the fabric can be immobilized as soon as they are hooked in a comb, while others are still called up that they themselves are hooked.

 In practice, the installation can include a training mat on which the fabric rests. Its coefficient of friction is such that it causes the fluff by overcoming the friction forces arising on the comb; but when an intermediate zone 5 is hooked in the comb, the fabric is immobilized and the mat no longer communicates with the fabric other than a certain tension which is insufficient to unhook the fabric from the comb or to damage it. The threads of the fabric constituting the zone 5 thus remain stretched which can be useful to facilitate the planned operation, such as a cut.

 When the strip 1 begins to run, the end of the combs 101 bears on the underside of the element 4 of the fabric strip (FIG. 4A).

 When the intermediate zone 5 is above a comb 101, the latter straightens (FIG. 4B) and the downstream edge 8 of the element 3 abuts against the comb 101 locked in the vertical position by the finger of blocking 107 (figure 3).

Element 3 possibly continues to be supplied, and in this case accumulates at the rear of the comb
101 by forming folds (Figure 4C). If these folds are
considered annoying, one can provide for the positive drive means of the strip, upstream of the combs, a sectional drive controlled by the penetration of the combs. But, when the local accumulation of folds is not a problem, it is easier to plan a positive training by means of a couple
mat and pressure roller.

 A detection device, known per se, controls the movement of the fabric.

The fact that the combs 101 pivot independently of each other makes it possible to correct the edge aw 8 i of the element 3, as illustrated in the areas 5A to 5D. there it is represented in plan the band
1 advancing in direction 2 below the stop device which, for example, comprises eight combs
101a to 101h, aligned on a reference line corresponding to the axis 103.

When the second fabric element 4 scrolls above the combs, they are all in the position indicated in FIG. 4A. As soon as the most downstream part of the deformed intermediate zone 5 (on the left in FIG. 5) comes to pass over one or more combs, these are raised: thus in FIG. SA, the combs 101a and 101b have been able to get up first; the comb 101a already retains the downstream edge 8 of the element 3, that is to say the comb l01a immobilizes a sec
longitudinal length of the strip. During this time, the other longitudinal sections 1b, 1c, etc., continue to advance, the section 1b to be immobilized soon in turn.

 Gradually, the combs 10lc and 101g can straighten (Figure 5B) and maintain or will maintain the edge 8 of the element 3.

 The element 4 continuing to be called, the longitudinal sections of the strip not yet immobilized by the combs continue to advance; thus in Figure SC, all of the combs except 101e pass through the fabric.

The edge 8 therefore progressively aligns with the line formed by the combs, this alignment is achieved completely when all the combs are lifted
(Figures 5D).

 The positive supply of the fabric, if it was not of the sectional type controlled by the straightening of the combs, can then be interrupted. Folds 110 may have formed upstream of the straightened combs first, but these, which are moreover minimal in 3 cases of the current deformations of the medial areas, markedly less accentuated than in the drawing, do not interfere with the majority of the operations planned on elements 3 and 4 after their immobilization.

When the fabric is immobilized, the axis 103 is pivoted in the opposite direction to the advance of the fabric
(arrow F, figure 3). Rings 111 (Figure 2) fixed on this axis 103 drive through a finger 112, the combs which have not been lifted.

This control of the position of the combs, which is in principle unnecessary, is carried out as a safety measure when a tool must pass near the combs.

 After having carried out the planned operation, such as a cutting or making operation, in order to be able to resume movement of the fabric, it is necessary to tilt all of the combs below the level of the fabric.

This tilting is obtained by the descent of a bar 113 which carries the locking rights 107 (Figure 2). This bar 113 carries a bent sheet 114 which in turn comes into contact with a finger 115 carried by the combs 101.

The bar 113 continuing its downward movement, the sheet 114 rotates the combs 101 in the direction of movement of the fabric (opposite direction of the arrow F) simultaneously the shaft 103 pivots to return to its initial position. When the element 3 is located above the area of action of the combs, the bar 113 rises to its rest position and the fingers 104 press again on the fabric. A new cycle is started to rectify a new intermediate zone.

 The stop device has been described placed under the fabric, but it is also possible to arrange it above the fabric strip, the fingers 104 of the combs resting on the upper face of the fabric.

 it has been shown for this first mode of ~ llination eight combs. It is however understood that the number of combs depends on the width of the strip, their spacing being a function of the deformability of the latter, and that the combs can have one or more fingers.

 According to a second embodiment represented in FIGS. 6 and 6A, the strip 1 also moves in a plane in the vicinity of the stop device 200, by means of known separate guide means or forming part of the means for driving the strip .

 The stop device consists of a series of combs or simple fingers 201 mounted on bent levers 202 articulated on axes -203 parallel to the direction of movement 2 of the fabric and mounted on a fixed frame 204. When the zone intermediate 5 separating the two elements 3, 4 passes under the fingers 201, these penetrate into this zone and block the progression of the front edge 8 of the element 3. The process of rectification of the deformed zone 5 is the same as that described with the first embodiment.

 After carrying out the operation reviewed on the elements 3, 4, the fingers 201 are raised by moving a bar 205 transversely carrying arms 206 which act on the bent part of the lever 202. When the strip progresses for a new rectification operation, the control bar 205 is brought back into place.

The fingers 201 can also be arranged below the fabric, in which case the fingers are applied to the fabric by means of a spring.

 A third embodiment is distinguished by its simplicity. As shown in FIG. 7, the installation comprises, apart from drive means not shown, guide means constituted in particular by two idle rollers 301 and 302, parallel, which cooperate with the stop device 300 so that the strip 1 or at least the fabric elements 4 (then 3) of the strip, pass over the combs or the fingers 303 at an obtuse angle. The fingers 303 (or the combs) are fixedly mounted on a control rod 304, itself fixed during the actual stopping process. Due to the tension of the strip due to its call by the downstream drive means, the fingers 303 press on the element 4 which scrolls with a certain force.

 This force of application of the comb on the strip means that, when the most downstream part of the intermediate zone 5 arrives at one or more fingers 303, these immediately pass through the fabric and then block the downstream edge 8 of element 3, thereby immobilizing the corresponding longitudinal section or sections. The rest of the operations are analogous to those described for the first two embodiments.

 it should be noted that the efficiency of the system is verified experimentally despite its great simplicity, for the usual deformations observed on the fabric strips (the intermediate zone 5 having a maximum deformation in the direction of the length of the strip which can be about 4 cm for a width of one meter).

 Provision may be made, if the need arises for deformations of more accentuated intermediate zones, to mount the fingers 303 elastically on the bar 304, which facilitates their penetration into the tissue.

 As has been said, the bar 304 remains fixed during the grinding operation and the cutting or making operation which follows. Once this has been completed, the bar 304 can be retracted to release the fabric and then replaced (arrow 305) when the strip restarts for the next correction.

 The fingers 303 are terminated by a filament element 306 arched in a plane and orientates in the direction 2 of arrangement of the strip 1 so as to slide easily m3r.t on the solid fabric (elements 4, 3) which passes over the fingers , and to be inserted between the warp threads of the intermediate zone 5 to cross and immobilize the strip of fabric.

Claims (11)

1. Method for stopping a moving strip of fabric, for stopping the strip in a manner a. making a transverse line defined on the strip coincide with a fixed reference line, characterized in that a plurality of longitudinal sections (la, ..., lh) of the strip (1) which is running is monitored, and , when, in a given section, the transverse line (2) defined on the strip arrives in coincidence with the fixed reference line, the given section (la, ..., lh) is immobilized, while continuing to do scroll the sections for which the transverse line is not yet coincident with the reference line. 2. Method according to claim 1, characterized in that immobilizes a given section by immobilizing e-elements passing through the fabric. 3. Method according to claim 2, in the case where the fabric strip is composed of upstream downstream of at least a first (3) and a second (4) fabric elements separated by an intermediate zone (5) of warp threads without weft threads, the downstream edge of the first element constituting the transverse line (8) defined on the strip, characterized in that one uses both to monitor and immobilize each longitudinal section (la, ... , lh) of the strip a comb (101,201,303) applies to the strip in movement so that it rests and slides on the surface of the second element (4) when the latter passes in front of the comb, and crosses the fabric when the intermediate zone (5) passes in front of the comb, whereby the downstream edge (8) of the first element (3) abuts against the comb which immobilizes the corresponding section (la, ..., lh). 4. Installation for driving a strip of detof fe implementing the stopping method according to claim 3, characterized in that it comprises a) a stopping device (100,200,300) consisting of a plurality of combs (101,201,303) lines on the reference line; b) means for adjusting the respective arrangement of the combs (101,201,303) and of the strip (i) so that, when the second element (4) passes in front of a comb, the latter slides on the surface of the second element (4 ) by leaning on it, and when the intermediate zone (5) scrolls past the comb, it crosses the fabric; and c) drive means; drive of the strip capable of causing, when one or more longitudinal sections of strip are immobilized, the other sections. 5. Installation according to claim 4, characterized in that the drive means comprise, downstream of the combs, a friction drive device.  6. The installation according to claim 4, characterized in that the drive means comprise, er zips of the combs, and their corresponding, a plurality of drive devices independent of each other respectively slaved to the penetration of the corresponding combs. 7. Installation according to any one of claims 4 to 6, characterized in that the stop device -comprises means (114,205,305) for disengaging all of the combs from the fabric. 8. Installation according to any one of claims 4 to 7, characterized in that it comprises means for guiding the strip in a plane in the region of the combs, in that the stop device  (100) consists of a plurality of combs (101) capable of pivoting independently around the same transverse axis (103), and angularly recalled so that each comb (101) presses by sliding on the surface of the second element (4) of fabric when the latter passes in front of the comb and passes through the fabric when the intermediate zone (5) passes, taking an angular position of immobilization limited by a stop. 9. Installation according to any one of claims 4 to 7, characterized in that it comprises means for guiding the strip in a plane in the region of the combs, and in that the stop device  (200) consists of a plurality of combs (201) mounted on bent levers (202) articulated on axes (203) parallel to the direction of movement 12) of the strip and angularly recalled so that each comb (201 ) presses by sliding on the surface of the second element (4) of fabric when the latter passes in front of the comb and crosses the fabric when the intermediate zone (5) passes by taking an angular position of immobilization limited by a stop. 10. Installation according to any one of claims 4 to 7, characterized in that it comprises means for guiding the strip consisting of two deflection rollers (301,302) parallel on the one hand, and combs (303) of the stop device (300) on the other hand, which are fixed on a transverse bar (304) between the two rollers (301,302) and protrude from one side of the plane of the rollers so that the second element (4) runs on the combs (303) at an angle, whereby, when the second element of the fabric (4) passes in front of a comb, the latter presses by sliding on the surface of the element, and when the intermediate zone (5) scrolls past a comb, it enters the fabric. 11. Installation according to any one of claims 4 to 10, characterized in that each comb comprises one or more fingers (104,201,303) terminated by an element (306) filiform arcuate plane, oriented in the direction (2) of advancement of the band.