FR3126430A1 - Tuck-in system for warp yarn spool support creel and corresponding tuck-in method - Google Patents

Abstract

The invention relates to a drawing-in system for a warp yarn support creel, comprising a holding system (82) and a multiple guide (84) intended to be arranged on either side of a guide plate (72) creel, the holding system (82) being shaped to hold a plurality of warp threads (30) opposite the guide eyes (70) made in the guide plate so that the held warp threads extend in a plane substantially parallel to the guide plate, each opposite an eyelet, the multiple guide comprising a support of a plurality of hooks (98) parallel to each other and shaped for the simultaneous insertion of the hooks into the guide eyelets so as to grip the warp threads held by the holding system and to tuck the wires simultaneously through the guide eyes. Figure for abstract: Figure 6

Description

Tuck-in system for warp yarn spool support creel and corresponding tuck-in method

The technical field of the present invention is that of the manufacture of composite material parts for turbomachines, and more particularly the production by three-dimensional or multilayer weaving using a Jacquard-type loom of fibrous reinforcement structures for such parts obtained.

The invention relates to a drawing-in device for a creel supporting warp yarn bobbins and a drawing-in method using such a device.

Composite materials make it possible to produce structural parts with fibrous reinforcement and densified by a matrix having a lower overall mass than these same parts when they are made of metallic material.

The 3D or multi-layer weaving of fibrous structures intended to constitute the fibrous reinforcement of a composite material part is carried out in a Jacquard-type weaving loom, for example to produce turbojet parts such as fan blades, a retention and straighteners.

There schematically illustrates such a loom 10 of the Jacquard type used for producing fibrous structures or fabrics obtained by multilayer weaving between a plurality of layers of warp threads 30 and a plurality of layers of weft threads 31.

In known manner, the weaving loom 10 is equipped with a Jacquard machine 11 supported by a superstructure not shown on the . The loom 10 also comprises a harness 20 consisting of a stuffing board 21 and control wires or heddles 22, each heddle 22 being connected at one end to a control hook 12 of the Jacquard machine 11 and at the other end to one of the return springs 13 fixed to the frame 14 of the loom 10.

Each heald 22 comprises an eyelet 23 through which a warp thread 30 passes. The healds 22 and their associated eyelet 23 are driven by a substantially vertical oscillating movement represented by the double arrow F under the tensile forces exerted respectively by the hooks 12 and the return springs 13. The healds 22 make it possible to lift certain warp threads 30 and thus create a shed 15 allowing the introduction of weft threads 31. Each heald is actuated and controlled individually which makes it possible to raise or lower each warp thread. It thus becomes possible to achieve the spacing of the warp threads necessary for the passage of a lance which carries the weft thread and to weave complex patterns and to pass the warp threads from one layer to another allowing the creation of a three-dimensional fibrous architecture. After each pass of weft thread, a beating reed 40 compacts the fabric that comes out of the loom.

The healds 22 are distributed spatially according to the position of the holes 210 of the topping board 21, that is to say along a plurality of columns 211 and rows 212. The density of the holes 210 in the board of padding corresponds to the density of the fabric to be produced, that is to say that there is in the padding board a spacing between each column of holes equivalent to that present between each column of warp in the fabric to be produced.

It is customary to equip a Jacquard loom with a numerical control and to weave in an automated way shapes with variations in thickness, variations in width and unbindings.

Certain fibrous structures, such as for example those intended to form reinforcements for blades made of composite material of aeronautical engines, require a very dense weave with a texture in particular of a relatively tight warp in order to confer good mechanical strength on the part. The warp thread count is the number of warp threads per unit length.

The production of 3D woven preforms, such as fan blades or casings, requires a very large number of warp threads, for example 6500 threads for the production of a fan blade.

The warp threads 30 are drawn from spools 50 arranged on a creel 60 upstream of the Jacquard mechanism 11 of the loom 10. The illustrates such a creel 60 comprising multiple supports 62. Each support 62 of the creel is fixed to a frame of the creel and supports several coils 50 of warp threads 30.

Each reel 50 is rotatable around an axis so as to be able to unwind its warp yarn.

The coils are distributed over the different supports 62. For each support 62, they are distributed spatially into two parallel arrangements, each arrangement comprising a plurality of rows and columns according to the example of the .

Given the large number of coils 50 of warp threads 30 necessary for the production of composite material parts for turbomachines, the coils are more or less distant from the Jacquard mechanism 11 of the loom 10.

In order to limit the threads from tangling, each warp thread 30 can pass through guide eyelets 70 of guide plates 72 and then through a hole 74 of a collecting board 76 similar to the stuffing board 21 , and finally crosses the eyelet 23 of a heddle 22.

The further the coil of a warp yarn is from the loom, the more the warp yarn 30 passes through successive guide plates 72, for example between 2 and 6 guide plates for coils spaced between 5 and 20 m from the loom. to weave.

When preparing weaving machines for the manufacture of 3D woven preforms, such as fan blades or casings, it is necessary to tuck in a very large number of yarns from the end of the creels to the loom. The drawing-in operation consists of passing each warp thread one by one through the guide eyelets of one or more successive guide plates once the coils of warp threads have been installed on the supports of the creel.

Currently, this operation is manual. Thus, the drawing in of approximately 6500 warp threads for the production of a fan blade requires two operators, one to present a warp thread in front of a guide eyelet of a guide plate and the other to grasp the warp thread using a hook type tool and pull it through the guide eyelet. This drawing-in operation, preliminary to weaving, is not very ergonomic and very long, about two weeks of work under current conditions. The operation being only manual, the risk of error is therefore significant. The most frequent error is the passage of a thread in the wrong eyelet which almost always generates a shift, certainly easily detectable, but which forces everything to be removed and then re-entered.

Based on these observations, one objective of the invention is therefore to overcome the aforementioned drawbacks.

To this end, the invention relates to a tucking-in system for a creel for supporting reels of warp threads, the creel comprising at least one plate for guiding the warp threads to a loom, each warp thread being configured to pass through guide eyelets formed in the guide plate, the re-entry system comprising a holding system and a multiple pass intended to be arranged on either side of the guide plate,

the holding system being shaped to hold a plurality of warp threads opposite the guide eyelets so that the held warp threads extend in a plane substantially parallel to the guide plate, each opposite an eyelet,

the multiple guide comprising a support for a plurality of gripping means parallel to each other and shaped for the simultaneous insertion of the gripping means into the guide eyelets so as to grip the warp threads held by the holding system and to tuck the wires simultaneously through the guide eyes.

Thus, the invention proposes a tool allowing a single operator to carry out the drawing-in operation more quickly than at present by simultaneously drawing in several warp threads at the same time.

Indeed, by processing several warp threads simultaneously and no longer one by one, the time required for the entry of the warp threads into the guide plates is greatly reduced.

In addition, the invention makes it possible to carry out by a single operator the steps of presenting and receiving the warp yarn at the level of a guide eyelet, where currently the presence of two operators is necessary.

In addition, work ergonomics are improved by the invention, resulting in greater control of the operation and reducing the risk of entry error. The drawing-in operation is thus streamlined and the time saving for this drawing-in operation is maximized and estimated at approximately 75%.

The retracting system according to the invention may comprise one or more of the following characteristics, taken separately from each other or in combination with each other:

• the holding system comprises a rectangular frame formed of a first longitudinal bar intended to support the warp threads, of a clamping device extending parallel to the first longitudinal bar and intended to hold the warp threads and of two bars opposite sides joining the first longitudinal bar to the clamping system;
• the clamping device comprises an upstream longitudinal flange and a downstream longitudinal flange held together by clamping;
• the upstream longitudinal flange and the downstream longitudinal flange comprise at least one part intended to be in contact with the warp threads when the clamping device is tightened, and in which the at least one part is covered with a layer of a material adapted to protect the warp yarns while maintaining them during the drawing-in operation and to allow them to slide under the action of an operator in order to release them from the clamping device, preferably the material is felt;
• the first longitudinal bar comprises a warp yarn guide means configured to separate the warp yarns held by the holding system;
• the guide means comprises notches configured to separate the warp threads held by the holding system;
• the gripping means are arranged in line;
• the multiple pass comprises at least 10 gripping means, preferably at least 22 gripping means;
• the tuck-in system comprises another holding system shaped to hold the warp threads that have passed through the guide eyelets;
• each gripping means comprises a shaped hook to grip a warp yarn held by the holding system and retain it.

The invention also relates to a method of drawing in warp threads through guide eyelets of a guide plate using a drawing-in system as described previously, the method comprising:

- hold the warp threads in the holding system separately and parallel to each other;

- place the holding system upstream of the guide plate so that the warp threads held extend in a plane substantially parallel to the guide plate, each facing a guide eyelet;

- simultaneously insert the gripping means of the multiple guide through the guide eyelets up to the plane in which the warp threads extend, the multiple guide being arranged upstream of the guide plate;

- Seize each warp thread held by the holding system by means of gripping by translation of the holding system in a direction perpendicular to the warp threads held and parallel to the guide plate;

- Simultaneously pass the warp yarns seized by the gripping means through the guide eyelets; And

- Release the warp threads from the holding system arranged upstream of the guide plate.

Advantageously, the method also comprises a step of holding the warp threads after having passed through the guide plate by a holding system separately and parallel to each other.

Another object of the invention relates to a method for supplying warp yarns to a loom from a support creel for the warp yarn bobbins, the creel comprising guide plates for the warp yarns up to the weaving loom, each warp thread being configured to pass through guide eyelets of at least one guide plate, a plurality of warp threads being simultaneously tucked into the guide eyelets of a plate according to the tuck-in method such as described above, the process being repeated for each guide plate to be traversed by the plurality of warp threads.

The present invention will be better understood and other details, characteristics and advantages of the present invention will appear more clearly on reading the description of a non-limiting example which follows, with reference to the appended drawings in which:

there , already described, is a schematic perspective view of a Jacquard-type loom according to the prior art,

there , already described, schematically illustrates a perspective view of a creel arranged upstream of the weaving loom of the ,

there is a very schematic view of a weaving installation comprising a loom and a creel,

there schematically represents a perspective view of a system for holding a retracting system according to the invention during the step of positioning the holding system in front of a guide plate,

there schematically illustrates a perspective view of the tuck-in system during the step of inserting the hooks through the guide eyelets,

there is the same perspective view as the during the step of gripping the warp threads by the hooks, and

there is the same perspective view as the during the step of crossing the guide eyelets by the warp threads thanks to the hooks.

In the various figures, similar elements are designated by identical references. In addition, the various elements are not necessarily represented to scale in order to present a view making it easier to understand the invention.

Claims (11)

Drawing-in system (80) for a creel for supporting reels of warp threads (30), the creel comprising at least one guide plate (72) for the warp threads up to a loom (10), each thread of chain (30) being configured to pass through guide eyelets formed in the guide plate, the drawing-in system comprising a holding system (82) and a multiple guide (84) intended to be arranged on either side guide plate,
the holding system (82) being shaped to hold a plurality of warp threads (30) facing the guide eyes (70) so that the held warp threads extend in a plane substantially parallel to the guide plate (72), each opposite an eyelet (70),
the multiple pass (84) comprising a support (97) of a plurality of gripping means (98) parallel to each other and shaped for the simultaneous insertion of the gripping means into the guide eyelets (70) so as to grasping the warp threads (30) held by the holding system (82) and entering the threads (30) simultaneously through the guide eyes (70). Drawing-in system according to Claim 1, in which the holding system (82) comprises a rectangular frame (85) formed by a first longitudinal bar (86) intended to support the warp threads (30), a clamp (87) extending parallel to the first longitudinal bar and intended to hold the warp threads and two opposite side bars (88, 89) joining the first longitudinal bar to the clamping system. A tuck-in system according to claim 2, in which the clamping device (87) comprises an upstream longitudinal flange (91) and a downstream longitudinal flange (92) held together by clamping. Drawing-in system according to Claim 3, in which the upstream longitudinal flange (91) and the downstream longitudinal flange (92) comprise at least one part intended to be in contact with the warp threads (30) during tightening of the clamping device , and wherein the at least a portion is covered with a layer of felt. A tuck-in system according to any of claims 2 to 4, wherein the first longitudinal bar (86) has notches (95) configured to separate the warp threads held by the holding system. A tuck-in system according to any one of claims 1 to 5, wherein the gripper means (98) are arranged in line. Drawing-in system according to any one of Claims 1 to 6, in which the multiple pass (84) comprises at least 10 gripping means, preferably at least 22 gripping means. Drawing-in system according to any one of Claims 1 to 7, comprising another holding system shaped to hold the warp threads having passed through the guide eyelets. Drawing-in system according to any one of Claims 1 to 8, in which each gripping means (98) comprises a shaped hook to grip a warp yarn held by the holding system and retain it. Method of drawing in warp threads (30) through guide eyes (70) of a guide plate (72) using a drawing-in system (80) according to one of the preceding claims, the method comprising:
- maintain the warp son (30) in the holding system (82) separately and parallel to each other;
- placing the holding system (82) upstream of the guide plate (72) so that the warp threads (30) held extend in a plane substantially parallel to the guide plate, each facing a guide eyelet (70);
- simultaneously insert the gripping means (98) of the multiple guide (84) through the guide eyelets (70) up to the plane in which the warp threads extend, the multiple guide being arranged downstream of the plate guidance;
- Seize each warp yarn (30) held by the holding system (82) by a gripping means (98) by translation of the holding system in a direction perpendicular to the warp yarns held and parallel to the guide plate;
- simultaneously pass the warp yarns (30) seized by the gripping means (98) through the guide eyelets (70); And
- releasing the warp threads (70) from the holding system (82) arranged upstream of the guide plate (72). Drawing-in method according to claim 10, comprising a step of holding the warp threads after having passed through the guide plate by a holding system separately and parallel to each other.