FR3105270A1 - Velvet loom - Google Patents

Abstract

Weaving loom (1) for velvet allowing, on the one hand, the alternative weaving of two layers (2, 3) of superposed fabric each composed of warp threads (4) and weft threads and linked one to the other. the other by pile yarns (5) and, on the other hand, the separation of the two layers (2, 3) by a razor (33) moved laterally between the two layers (2, 3) to cut the pile yarns (5). According to the invention, the weaving loom (1) comprises, for the insertion of a weft thread into a shed formed by the warp threads (4) of a sheet, a mechanism comprising a single lance (13) with alternating movements. Figure for the abstract: Fig. 4

Description

Velvet loom

The invention relates to the field of velvet weaving looms, and relates more particularly to a so-called double-ply weaving loom.

Prior art

In the state of the art, there is known a loom for weaving velvet, double layers, that is to say allowing on the one hand, the simultaneous weaving of two superimposed layers of fabric each composed of warp threads and of weft threads and linked to each other by pile threads and, on the other hand, the separation of the two layers by a razor moved laterally between the two layers to cut the pile threads.

When the two sheets of fabric are separated, the pile threads form the velvet of each of them.

For the insertion of the weft threads in the sheds formed by the warp threads, it is known to make back and forth movements of a wooden shuttle comprising two metal points at the ends, and a reel of thread weft called bobbin.

This old technique has limited reliability and efficiency.

It is also known to use a pair of lances, with each lance moving in the direction of the other to meet halfway across the width of the web. A first lance grabs the weft yarn on one side of the ply and moves it inside the shed of a ply to transfer it to the other lance which pulls the weft yarn to the other side of the tablecloth.

As for obtaining the velvet pile, the high ply takes off from the flap by 3 to 5 millimeters, it is difficult to catch the weft thread at the change because the lances are raised and the exchange of weft thread in the middle does not take place at all or not correctly.

This solution has increased reliability and efficiency compared to the shuttle technique, but can still be improved.

One of the aims of the invention is therefore to propose a loom for weaving velvet, double layers, whose reliability and performance are improved.

To this end, a velvet weaving loom has been developed allowing, on the one hand, the alternative weaving of two superimposed layers of fabric, each composed of warp and weft threads and linked one to the other. on the other by hair yarns and, on the other hand, the separation of the two sheets by a razor moved laterally between the two sheets to cut the hair yarns.

According to the invention, the loom comprises, for the insertion of a weft thread into a shed formed by the warp threads of a sheet, a mechanism comprising a single reciprocating lance.

In this way, the use of a single lance makes it possible to increase the reliability of the loom, and to increase its production yield.

In order to further improve the reliability of the loom, the razor is moved by a pneumatic control system. This system is fast and reliable.

Preferably, so that the loom can produce a so-called shaped weave, that is to say, selected according to a particular pattern, the pile yarns are controlled by a Jacquard mechanism, preferably electronic, associated with a return system mechanical angle to control the Jacquard mechanism.

In a known way, the Jacquard mechanism works with a system of creels of bobbins of pile yarn. Thus, according to another characteristic of the invention, the loom is associated with a system of creels of hair yarn reels positioned on a platform mounted above the loom. This characteristic makes it possible to optimize the land use of the loom, and to increase the length of the pile threads.

Advantageously, each coil of pile yarn is subject to an individual tensioner positioned in front of each coil, the tensioned yarns of the same level of creel are sent into a reed, in particular before plunging into the warp yarns. This characteristic makes it possible to perfectly control the tension of the pile threads.

According to a particular embodiment, each pile yarn spool comprises a hollow mandrel around which the pile yarn is wound and one end of which is flared into a cone so as to form a support for the base of the pile yarn, and each bobbin of hair yarn is surrounded by an elastic sleeve. This type of coil is known to those skilled in the art by the English name "Kingspool". This feature avoids the rewinding of pile yarns, the yarns are directly unwound from the Kingspool bobbins. Furthermore, the elastic sleeve makes it possible to maintain the stability of the bobbins of hair yarn, further increasing the reliability of the loom according to the invention.

According to a particular embodiment, the pile yarns coming from the creels plunge through the warp yarns to a return system, and then go up again crossing the warp yarns from above; the return system is subject to means of vertical displacement making it possible to tension and unwind the coils of pile yarn.

These characteristics make it possible to effectively adjust the tension of the bristle threads and to have spools containing 8 to 10 times more thread than an ordinary rewound spool.

Preferably, the displacement means are in the form of a tension bar positioned to press on the return system, and controlled by a pneumatic cylinder.

Advantageously and in order to participate in the reliability of the loom according to the invention, said loom comprises a stop motor adapted to block the loom, in particular with a safety brake, to prevent its reverse return in the event of a power cut. 'electricity.

Other characteristics and advantages of the invention will emerge clearly from the description which is made of it below, by way of indication and in no way limiting, with reference to the appended figures, in which:

Figure 1 is a front view of the loom according to the invention, in front of which is positioned a platform.

Figure 2 is a side view of the loom.

Figure 3 is a rear view of the loom.

FIG. 4 is a side perspective view illustrating the leaf with the games of healds and the rod of the lance.

FIG. 5 is a perspective view illustrating the rod and the gripper of the spear, inserted into a host of warp threads.

FIG. 6 is a perspective view illustrating the electronic Jacquard mechanism and the stopper motor, positioned on the platform above the loom.

FIG. 7 is a perspective view of the pile yarn spool creels, positioned on the platform above the loom.

FIG. 8 is a perspective detail view of the coils of surrounded pile yarn, of the elastic sleeves, and of the individual tensioners positioned in front of the coils.

FIG. 9 is a perspective view illustrating the pile yarn return system and its vertical displacement means making it possible to tension and unwind the bobbins of pile yarn.

FIG. 10 is a perspective view illustrating the rolls for winding up the woven velor sheets and the pneumatic razor for separating the sheets.

Figure 11 is a view similar to that of Figure 10, seen from the other side of the rollers, illustrating in detail the arrangement of the pneumatic razor.

Detailed description of the invention

With reference to Figures 1 to 11, the invention relates to a weaving loom (1) for double-ply velvet (2, 3).

In general, the layers (2, 3) of fabric consist of warp threads (4) and weft threads. The warp threads (4) are parallel and run along the length of the ply, and determine the length and width of the ply. The weft threads are perpendicular to the warp threads (4) and cross them or are inserted between them.

In a known way, the expression "double layers" means that the loom (1) allows the alternative weaving of two layers (2, 3) of independent fabric, one above the other, linked initially to each other by pile threads (5) which, after separation, form the velvet of each of them.

Referring to Figures 1 to 3, and generally and well known to those skilled in the art, the weaving loom (1) the velvet comprises a frame (6), unwinding rolls (7) of the threads of warp (4), and weft unwinding rollers.

The loom (1) also comprises a structure (9) equipped with two sets of healds (10), a first set associated with an upper sheet (2) of warp threads (4), and a second set associated with a lower ply (3) of warp threads (4). The sets of healds (10) move vertically with to-and-fro movements to form the different sheds in which a weft yarn is intended to be inserted.

Referring to Figures 4 and 5, the weaving loom (1) comprises a reed (11) driven with an alternating tilting movement to comb the weft yarn inserted in the shed and tighten the weft, and also comprises means for cutting the combed weft yarn (not shown).

The loom (1) comprises in its upper part, a Jacquard mechanism (18), known to those skilled in the art, which controls the insertion of the pile threads (5). The pile threads (5) are for example polyester threads, covered with a metallic layer, of the type of those for example marketed under the name Lurex®.

For the insertion of the weft threads into the sheds of warp threads (4), the loom (1) comprises a mechanism comprising a single lance (13), for example mechanical, provided on one side of the loom ( 1). Referring to Figures 4 and 5, the lance (13) comprises, in the manner of a cylinder, an outer barrel (14) in which a rod (15) mounted to slide so as to be able to be driven in a va- back and forth by pressurizing the front or rear parts of the outer barrel (14). The rod (15) of the lance (13) is guided by sliding in the barrel (14) and therefore moves freely in the shed, relying neither on the warp threads (4) nor on the threads of hair (5), nor against the comb (11). This characteristic then makes it possible to eliminate the problem of weft thread exchange in the middle.

In a known way, the lance (13) comprises at its end a gripper (16) intended to grasp the weft yarn, supplied by a yarn presentation device positioned on one side of the loom (1).

As indicated, the lance (13) is moved back and forth during which the gripper (16) seizes the weft yarn presented by the presentation device, and brings it to the other side of the fabric in passing through the warp yarn crowds (4).

For this purpose and in a known manner, the heddles make it possible to lift part of the warp threads (4) so as to create crowds, between the lifted warp threads (4) and the warp threads which are not. The insertion of the weft threads is carried out by the to-and-fro movement of the lance (13) which then positions a weft thread at each pass.

The loom (1) also comprises other elements necessary for its operation, well known to those skilled in the art, so that they will not be described in detail.

The weft thread is inserted to alternately weave the upper ply (2) and the lower ply (3), connected to each other by pile threads (5).

The Jacquard mechanism (18), well known to those skilled in the art, has been adapted here to weave custom-made velvet. The loom (1) according to the invention comprises a platform (17) surmounting said loom (1), like a superstructure.

The platform (17) comprises for example uprights supporting the platform (17) at a height of 2 m for example. Referring to Figure 6, a bevel gear system (35) for mechanically controlling the Jacquard mechanism control shaft (18). The electronic Jacquard (18) mechanism makes it possible to eliminate the paper design. Furthermore, a stop motor (19) is also positioned on the platform (17), and is secured. The stop motor (19) is adapted to block the loom (1) to prevent it from rolling back in the event of a power cut.

Referring to Figures 6 to 8, creels (20) of coils (21) of pile yarn are also arranged in height, on the platform (17). Each creel (20) has a plurality of spools (21) of pile yarn which are positioned side by side by ten, and one above the other in shelving, also by ten. This new arrangement of the creels (20) makes it possible to have 10 to 12 times more length of pile yarn (5) on each coil (21) of pile yarn for the same grip on the ground, and to control the tension for a perfect unfolding.

Referring to Figure 8, the spools (21) of pile yarn are arranged substantially horizontally and each spool of pile yarn comprises a hollow mandrel (22) around which the pile yarn (5) is wound and of which one end is flared into a cone so as to form a support for the base of the pile yarn (5). This type of coil (21) is well known by the English name “Kingspool”.

In order to ensure the stability of the spools (21) of pile yarn, each spool is surrounded by an elastic sleeve (23), for example made of polyester which has preferably been pleated to allow the tracking of the cone when it decreases in volume. .

Each reel (21) is attached to an individual tensioner (24) positioned in front of each reel (21). Pile threads (5) stretched from the same level of creel are sent into a reed (26), see figure 7, before plunging between the warp threads (4).

Referring to Figure 9, the pile yarns (5) coming from the creels (20) plunge through the warp yarns (4) as far as a return system (27), and then rise again crossing the yarns chain (4) from above.

The return system (27) includes a back and forth to press the dancers and bring the pile threads to obtain the velvet

In order to tension and unwind the bobbins (21) of pile yarn, the return system (27) is subject to vertical displacement means (28) intended to create a to-and-fro movement of the dismissal (27).

For example, the means of vertical displacement (28) are in the form of a tension bar (29) positioned to press on the return system (27), for example connected, via a mechanism of return bars (30) and pivoting axis (31), to a pneumatic cylinder (not shown) which, when actuated, moves the tension bar (29) vertically.

In a conventional manner, the pile yarns (5) emerge from the warp at the top and enter a harness (32) of the Jacquard machine (18), controlled by the bevel transmission system (35), to coming to bind the lower and upper layers (2, 3) of warp threads (4).

Finally, with reference to Figures 10 and 11, at the exit of the loom (1), when the sheets (2, 3) have been joined by the pile yarns (5) and woven with weft yarns, the sheets ( 2, 3) are separated from each other by a razor (33) moved laterally between the two layers (2, 3) to cut the pile threads (5). According to the invention, the razor (33) is moved by a pneumatic control system.

The separate layers (2, 3) are then each wound around a roller (34).

It emerges from the foregoing that the invention provides a loom for weaving velvet, double layers, whose reliability and efficiency are improved. The loom according to the invention rotates faster and does not stop. It has a yield about 3 times higher than an ordinary shuttle loom for velvet.

Claims (10)

Velvet weaving loom (1) allowing, on the one hand, the alternative weaving of two layers (2, 3) of superposed fabric each composed of warp threads (4) and weft threads and linked one to the other. the other by pile yarns (5) and, on the other hand, the separation of the two layers (2, 3) by a razor (33) moved laterally between the two layers (2, 3) to cut the pile yarns (5), characterized in that it comprises, for the insertion of a weft thread into a shed formed by the warp threads (4) of a ply, a mechanism comprising a single lance (13) with alternatives. Weaving loom (1) according to Claim 1, characterized in that the razor (33) is moved by a pneumatic control system. Weaving loom (1) according to Claim 1, characterized in that the pile threads (5) are controlled by an electronic Jacquard mechanism (18). Weaving loom (1) according to Claim 3, characterized in that the Jacquard mechanism (18) is associated with a mechanical angle transmission system (35). Weaving loom (1) according to Claim 3, characterized in that it is associated with a system of creels (20) of bobbins (21) of pile yarn positioned on a platform (17) mounted above the loom. weave (1). Weaving loom (1) according to Claim 5, characterized in that each bobbin (21) of pile yarn is fastened to an individual tensioner (24) positioned in front of each bobbin (21), the pile yarns (5) stretched same level of creel are sent into a reed (26). Weaving loom (1) for velvet according to Claim 1, characterized in that each bobbin (21) of pile yarn comprises a hollow mandrel (22) around which the pile yarn (5) is wound and one end of which is flared in a cone so as to form a support for the base of the pile yarn (5), and each bobbin (21) of pile yarn is surrounded by an elastic sleeve (23). Pile weaving machine (1) according to Claim 5, characterized in that the pile threads (5) coming from the creels (20) plunge through the warp threads (4) to a return system (27) , and then go up again crossing the warp threads (4) from above; the return system (27) is subject to vertical displacement means (28) making it possible to tension and unwind the bobbins (21) of pile yarn. Weaving loom (1) according to Claim 8, characterized in that the displacement means (28) take the form of a tension bar (29) positioned to press on the return system (27), controlled by a pneumatic cylinder. Velvet weaving loom (1) according to Claim 4, characterized in that it comprises a stop motor (19) suitable for blocking the loom to prevent it from rolling back in the event of a power failure.