SYSTEM FOR CONTROLLING THE HEALD FRAMES OF DOUBLE-BEAM VERTICAL LOOMS

Abstract: A system for controlling the horizontal or near- horizontal head frames (4) of vertical weaving looms, of the type operated by an external weave forming machine (A) provided with control levers (18) acting in vertical planes, comprises a plurality of superimposed horizontal bars (17) extending over the entire width of the loom, each of which is connected to one of said control levers (18) so as to be made to perform an alternating rectilinear movement along its longitudinal axis. Each of said bars (17) has connected to it at least one heald frame (4) by means of a lever mechanism (21, 22) designed to convert said alternating rectilinear movement of the bar (17) in the direction of its longitudinal axis, into an alternating rectilinear movement of the heald frame (4) in a direction perpendicular to said axis.

Description: SYSTEM FOR CONTROLLING THE HEALD FRAMES OF DOUBLE-BEAM VERTICAL LOOMS O # O*O *O The present invention relates to a system for controlling the heald frames of double-beam vertical looms and in particular relates to a system of hinged lever mechanisms designed to transfer the control movements of an external weave machine to the two opposite sets of heald frames present in double-beam vertical looms. For a general description of vertically arranged double-beam weaving looms, reference should be made to the associated Italian patent application No. MI91 A002079 in the name of the same Applicant, the contents of which are understood as being incorporated here for the sake of reference. Below reference will be made to only some aspects of the vertical loom which are of particular relevance for the present invention, with a brief illustration being provided of the remainder of such a loom, useful for better understanding of the description given below. The general structure of the novel double-beam loom incorporating the heald frame control system according to the present invention is illustrated schematically in Figs. 1 and 2. In brief, the novel loom extends in the vertical direction and has a main body consisting of a central frame 1 having mounted on either side of it the devices forming two complete weaving lines which are arranged opposite one another and perfectly symmetrical with respect to a central vertical plane. Starting from the bottom zone of the loom, each weaving line comprises a warp beam 2, a drive bar 3 which arranges the warp yarns on a substantially horizontal plane, a warp stop device 1 2, a yarn-pulling bar 1 1 , a set of heald frames 4, a sley with a reed 5, a take-up cylinder 7 for the newly formed fabric 6 and, finally, a cloth winding beam 8 operated and supported by driving rollers 9 and 10. The loom also comprises a drive mechanism consisting of a single control CPU (not shown), a single main motor/clutch unit M, two twin transmission units T, which are both connected to the motor/clutch unit and are apt to transmit the movement thereof to a respective sley. One of said transmission unit is also apt to transmit the movement of the motor/clutch unit M to the weave forming machine A (hereinafter simply called weave machine) which operates the system of the present invention. The advantages of such an arrangement are fully described in the aforementioned patent application, to which reference should be made for better understanding also of the present invention. In the art, even though they have never been effectively used on an industrial level, it is known of single-beam vertical looms in which the problem exists of moving the frames by means of an extemal weave machine, said problem - not easily resolvable - also existing in double- beam vertical looms. In a vertically arranged loom, in fact, the heald frames lie substantially horizontally and it is therefore fairly problematic transferring to them the control movement of an external weave machine, in view of the fact that all the weave machines present on the market are designed to function in a vertical plane, in which plane the control lever mechanisms emerging from the machine itself lie. Leaving aside, therefore, for obvious cost-related reasons, the possibility of designing special-purpose weave machines with horizontally positioned control devices, the only remaining possibility is that of providing devices designed to transfer the control movements of a weave machine in a plane inclined at about 90° with respect to the normal vertical operating plane of the machine itself. These devices have hereto proved to be fairly complex and somewhat unreliable, so much so that it may be regarded as one of the reasons for the failure of this type of loom to be used on an industrial level. The object of the present invention is therefore that of providing a heald frame control system which can be operated by a normal commercially available weave machine without the need for any adaptation of the latter and which is designed to cause symmetrical movements of the pairs of corresponding heald frames on the two opposite weaving lines of a double-beam vertical loom, so as to allow the weaving of identical fabrics on both one side and the opposite side of the loom, as in fact is provided by the typical operation of this loom. Another object of the present invention is to provide a system for controlling the heald frames of a vertically arranged weaving loom which, although being specifically designed for a double-beam loom, may also be successfully applied to single-beam looms. A further object of the invention is to provide a control system of the aforementioned type which has a simple and strong structure and at the same time is particularly compact so that it may be housed without particular problems inside the frame of a doubie-beam vertical ioom. All these objects are achieved, according to the present invention, by means of a system for controlling the horizontal or near-horizontal heald frames of vertically arranged weaving looms - of the type operated by an external weave machine provided with a plurality of toggle-joint control levers lying in adjacent vertical planes - comprising a plurality of bars arranged above one another, lying in horizontal planes and extending over the entire width of the loom, each of which is connected to one respective lever of said toggle-joint levers so as to be made to perform an alternating rectilinear movement along its longitudinal axis, each of said bars having connected to it, moreover, at least one heald frame by means of a lever mechanism designed to convert said alternating rectilinear movement of the bar in the direction of its longitudinal axis, into an alternating rectilinear movement of the heald frame in a direction perpendicular to said axis. The invention will be better understood, however, from the following detailed description of a preferred embodiment thereof illustrated in the accompanying drawings, in which: Fig. 1 is a cross-sectional schematic view of a double-beam vertical loom incorporating the control system according to the invention; Fig. 2 is a front schematic view of the loom illustrated in Fig.1 ; Fig. 3 is a schematic perspective view of the control system according to the invention, showing, for the sake of simplicity, only one pair of heald frames; Fig. is a schematic front view, on an enlarged scale, of a part (i.e. the stacked longitudinal bars 21 and associated eyelets 25) of the control system according to the invention; Fig. 5 is a schematic side view of the control system according to the invention; and Fig.6 is a schematic, partially sectioned, plan view of the control system according to the invention. As briefly stated in the introduction, the problem faced by the inventor of the present invention has been that of transferring in an effective manner the control movements of an external weave machine, which lie in a plurality of adjacent vertical planes, to a double system of heald frames which must move alternatively in horizontal or near- horizontal planes. The problem is complicated by the fact that the frames to be operated for each weaving line of the double-beam loom are obviously greater than one in number, for example four as indicated in the drawings, and also by the fact that the control levers which emerge from the weave machine are located very close to one another, at a distance identical to the mutual distance separating the heald frames in normal horizontal looms. This problem has been solved with the control system according to the present invention, which consists of a system of hinged levers with a simple, compact and strong structure, such as to be particularly suitable for withstanding the extremely rapid alternating movement imparted to it by the weave machine. In the embodiment illustrated in the accompanying drawings and in the following detailed description, exclusive reference will be made to a double-beam loom comprising four heald frames for each weaving line. The control system according to the present invention, however, may advantageously be used also with a larger number of heald frames, as well as in single-beam looms, with the same effectiveness. This system comprises, as its essential parts, a number of longitudinal bars 1 7 which receive the movement from respective toggle-joint levers 18 of a weave machine A, preferably through transmission levers 19 and link rods 20. The toggle-joint levers 1 8 are provided, in a manner known per se, with a travel adjuster, as clearly illustrated in Fig. 3. Each longitudinal bar 1 7 then transmits the movement to a pair of heald frames 4 arranged, respectively, on the right-hand side and left-hand side thereof through at least two right- angled levers 21 for each of said heald frames 4, which are pivotably hinged, by means of pairs of link rods 22, on the side of the longitudinal bars 17 and on the base of the frames 4. Considering in more detail the constructional features of the control system according to the present invention, it may be noted that the longitudinal bars 17 have a rectangular cross-section, extend over the entire width of the loom and are of a number corresponding to the maximum number of frames provided on each weaving line of the loom. The bars 1 7 are arranged stacked one on top of the other in the central part of the loom, and rest on respective supports 23 suitable for guiding the travel movement thereof in the direction of their longitudinal axis, while at the same time keeping them at the required distance in the vertical direction, said distance being related, depending on the angle of inclination of the heald frames 4 with respect to the horizontal, to the interaxial distance between the superimposed frames 4 of a same weaving line. Preferably the supports 23 consist of blocks of wear- resistant material with a low coefficient of friction, such as, for example, a composite material formed of bakelized fabric and carbon fibers, or similar products. The longitudinal alternating movement is transmitted to the bars 17 by the toggle-joint levers 18 of the weave machine A. The free end of each toggle-lever 1 8, only one of each is shown in Fig. 3 for greater clarity, is hinged with the bottom end of a transmission lever 19, the other end of which is hinged with the fixed structure of the loom. A link rod 20 is then hinged with one end in a position between the fulcrum and the end eyelet of the lever 1 9. The other end of the link rod 20, finally, is hinged with an eyelet 24 welded to the front end of the bar 17. It should be pointed out at this point that the distance between the individual toggle-joint levers 1 8 of the weave machine A is fixed and corresponds to the normal distance existing between the heald frames of horizontal looms. Since the eyelets 24 must comply with the same said distance, problems of space arise on their sides as regards connection of the link rods 20 thereto. These problems have been solved by adopting, for the eyelets 24, the staggered arrangement shown in Fig. 4, whereby the eyelets 24 with respect to a horizontal plane are staggered at the same distance as the toggle-joint levers 1 8, while with respect to a vertical plane they are staggered so that at least one side of each eyelet is clear of the adjacent eyelets. For example, in the embodiment illustrated herein and comprising four longitudinal bars 17, this result is achieved by arranging, on the front ends of said bars, the eyelets of the upper and Iower bars in the central positions and the eyelets of the central bars in the lateral positions. In this way it is possible to house, without interference, the hinging heads of the link rods 20 on the right of the eyelets 24 of bars I and II ( 1 7) and on the left of the eyelets 24 of bars III and IV (1 7), thus avoiding any modification in the distance between the toggle-joint levers 18 of the weave machine A. In order to allow transmission of the movement from the bars 1 7 to the heald frames 4, at the same time ensuring the change in direction of the movement itself from a longitudinal alternating movement (that of the bars 1 7) to a transverse alternating movement (that of the frames 4), provision is made, as already mentioned, for right-angled levers 21 , which are at least two in number for each heald frame. The levers 21 are hinged with the structure of the loom by means of their central eyelet 21 a which cooperates with pivots (not shown), fixed to the loom and each carrying a number of levers 21 equal to the number of heald frames 4 of each weaving line (four in the embodiment illustrated). The right-angled ends of the levers 21 are then hinged, via link rods 22, with lugs 25 projecting from the sides of the bars 17 and respectively from the bottom cross-piece of the heald frames 4. The lever mechanisms operating the heald frames 4 described hereto are reproduced in a perfectly symmetrical manner on both sides of the bars 17, thus obtaining the desired movement - identical in terms of magnitude and velocity and symmetrical in terms of direction - of the two sets of heald frames 4 forming part of the two opposite weaving lines of the double-beam loom which incorporates the control system according to the present invention. It is obvious, however, that said control system may, without any problems, be used also for single-beam vertical looms by merely eliminating the lever mechanisms operating the heald frames 4 on one of the two sides of the bars 1 7. The heald frame control system according to the present invention has been described with reference to a particular embodiment thereof, but it is obvious that numerous modifications and adaptations may be made to the invention by a person skilled in the art, without thereby departing from the scope thereof as defined in the accompanying claims.

Claims: Claims 1 . System for controlling the horizontal or near-horizontal heald frames (4) of vertically arranged weaving looms - of the type operated by an external weave forming machine (A) provided with a plurality of toggle-joint control levers ( 18) lying in adjacent vertical planes - characterized in that it comprises a plurality of bars (1 7) arranged above one another, lying in horizontal planes and extending over the entire width of the loom, each of which is connected to one respective lever of said toggle-joint levers ( 18) so as to be made to perform an alternating rectilinear movement along its longitudinal axis, each of said bars having connected to it, moreover, at least one heald frame (4) by means of a lever mechanism (21 ,22) designed to convert said alternating rectilinear movement of the bar (1 7) in the direction of its longitudinal axis, into alternating rectilinear movement of the heald frame (4) in a direction perpendicular to said axis. 2. Control system as claimed in claim 1 , wherein each of said bars ( 1 7) is connected to a respective toggle-joint lever (18) by means of an eyelet (24) fixed to one of its ends and lying in a vertical plane. 3. Control system as claimed in claim 2, wherein, with respect to a horizontal plane, said eyelets (24) are mutually staggered by a distance identical to that existing between the control levers (18) of the weave machine (A). 4. Control system as claimed in claim 3, wherein, with respect to a vertical plane, said eyelets (24) are staggered so that at least one side of each eyelet is clear of adjacent eyelets. 5. Control system as claimed in claims 3 and 4 comprising at least four bars ( 1 7), wherein said eyelets (24) are fixed onto the front ends of respective bars in such a way that, with respect to a horizontal plane, the eyelets (I, IV) of the upper and Iower bars are arranged in the central positions and the eyelets (II, III) of the central bars are arranged in the lateral positions. 6. Control system as claimed in any one of claims 2 to 5, wherein each of said bars (1 7) is connected to one respective toggle-joint lever ( 18) by means of a link rod (20) and a transmission lever ( 19), the link rod (20) being hinged with said eyelet (24) and with an intermediate point on the transmission lever (1 9) and the latter being hinged with the end of the toggle-joint lever (18) and with a fixed point of the loom. 7. Control system as claimed in claim 1 , wherein said bars ( 17) are supported by blocks of wear-resistant material with a low coefficient of friction, which guide the axial travel movement thereof and keep the distance between them at a predetermined value which is related, depending on the angle of inclination of the heald frames (4) with respect to the horizontal, to the distance between the superimposed heald frames (4). 8. Control system as claimed in claim 1 , wherein said lever mechanism comprises at least one pair of right-angled levers (21 ) for each heald frame (4), said levers (21 ) being hinged, in a central position (21 a) thereof, with the loom and, in two end positions thereof, with the bottom cross-piece of the heald frame (4), and respectively with the side of said bar (1 7), through respective link rods (22). 9. Control system as claimed in claim 8, wherein said right-angled levers (21 ) are arranged in groups, each group comprising a lever for each heald frame (4) of a weaving line, the levers of each group being hinged, in their central position (21 a), with a single pivot fixed to the loom.

Inventors: GENDELMAN MIKHAIL, GENDELMAN, MIKHAIL
Applicants: GENDELMAN MIKHAIL, SOMET SOCIETA MECCANICA TESSSI, GENDELMAN, MIKHAIL, SOMET SOCIETA' MECCANICA TESSSILE P.A.
Application year: 1996
Main classification: D03D41
IPC codes: D03C1, D03C5, D03D41