FR2688805A1 - Device for the twisting of stricks (handfuls) of flax - Google Patents

Abstract

Machine for the twisting of stricks of flax (6), characterised in that it comprises a twisting device (4) comprising at least one twisting element (23) driven in a movement of rotation about itself by means (38 to 45) and equipped with an engaging (taking) opening (34) via which a bundle of non-twisted fibres is introduced and in that it comprises means (17, 18) for holding the bundle of fibres (3) engaged in this twisting element (23) at a non-zero distance in such a way that this twisting element produces a twist in the bundle of fibres.

Description

Flax is a field crop that has the distinction of being harvested in two stages: when ripe, it is first uprooted and deposited on the ground in a succession of parallel stems called "swath". The alternation of hot and humid weather makes it possible to biologically degrade the connections between the fibers contained inside and at the periphery of the stems: this operation is called "retting".

When the degree of retting is satisfactory and the material is dry enough to be preserved, the flax is picked up in round or rectangular bales.

After storage, the extraction of the fibers from the stems is carried out following a succession of mechanical operations called "scutching": the flax is thus successively ginned to remove the seeds, crushed to break the wood of the stems, then eaten to remove the particles of wood, called "anas", which still remain attached to the fibers. Barking consists in vigorously scraping the fibers by steel blades mounted on a rotor.

After this cleaning, the flax fibers, called "dyed flax", leave the turbine either folded in a U on a bar, or spread on a strip. Before * being marketed, the fibers are sorted manually, and packaged in packages of a few hundred grams: the worker twists this package, which is then called a "handle". The handles are grouped together to form a set or pack of handles of approximately 15 to 20 kilograms, which are manually tied with strings. The sets are then pressed hard to obtain a 100 kilogram bale. It is in this form that flax is marketed.

The originality of this packaging finds its explanation in the following operation, called "combing", which consists in mechanically refining the material using increasingly fine combs, to finally achieve a continuous ribbon obtained by orientation of fibers in the longitudinal direction.

To feed the combing machine, the worker takes up the handles which have remained well individualized thanks to the twist. Without this operation, the recovery of a precise quantity of fibers would be very difficult.

 Until now, this twisting operation is done manually.

The object of the invention proposed here is to provide a machine capable of performing this twisting operation mechanically.

For this purpose, this machine contains a twisting device comprising at least one twisting element animated by a rotational movement on itself by means and provided with a gripping opening through which a bundle of non-twisted fibers is introduced and in what it includes means for holding the bundle of fibers caught in this twisting element at a non-zero distance so that this twisting element twists the bundle of fibers.

This device is powered by bundles of fibers formed manually or mechanically.

Advantageously, the device can also contain an automatic separation system of the sheet which supplies the device with bundles of fibers.

The invention may also include means for stabilizing the twisted handle consisting of pressure elements.

After the action of the twisting device, the twisted part of the bundle of fibers can be maintained by new holding means in addition to or replacing the holding means of the handle described above, which transport the material to elements of pressure which effect this compression action at least on the twisted part to avoid untwisting of the twisted handle.

For the practical execution of the invention, the twisting element is constituted by a pinion comprising a recess in its central part opening onto a portion of its circumference which is called "gripping opening".

The device comprises means for holding and transporting sets of non-twisted fibers. The twisting element is animated by transmission means which allow it simultaneously to turn on itself and to follow the path of the bundle of fibers held by the means described above.

To ensure the twisting of the fibers during the rotation of the twisting element, the gripping opening comprises an element which holds the bundle of fibers to force it to rotate on itself.

The features and advantages of the invention are illustrated below by the description of a device for twisting the handles of textile fibers, without limiting the invention. The following figures illustrate this device.

Figure 1 shows a side view of the transfer of dyed linen comprising a twisting device for the handle.

Figure 2 shows a top view of the same device shown in Figure 1.

Figure 3 details the twisting device of Figure 2, seen from above.

Figure 4 is a section along line IV-IV of Figure 3.

Figure 5 is a section along the line V-V of Figure 2, with an enlarged scale.

Figures 1 & 2 show the downstream part * a linen tiller (1), a device (2) for the formation of bundles of untwisted fibers (3), a twisting device (4), a transport device (5 ) twisted handles (6) to a pack of handles (7), as well as a binding device (8) of this pack (7), of which only the front part is shown.

The flax tiller (1) is a known machine which extracts and cleans the fiber contained in the stems. The fibers are delivered by a transport device (11) in the form of a sheet (9), folded in half on a bar (10) which extends the seamer (1). This sheet (9) is pushed further towards a zone (12) called "sorting", where the fibers of lower quality are extracted manually.

Then, the sheet (9) is transported to the device (2) by a means of transport (13). This means (13) has 4 wheels (63), arranged in a square, one of which is rotated.

A belt (64) is tensioned in contact with the other wheels (63) so as to ensure their synchronization. Two forks (65) are fixed on two superimposed wheels (63) by means of two free axes in rotation and offset from the center of the wheels.

The device (2) comprises two parallel endless belts (66), stretched between two pulleys (67) and (68) and driven.

Between these belts (66) is mounted at least one comb (69), the trajectory of which allows a handful of non-twisted fibers to be moved from the ply (9) to the horizontal bar (10). This device (2) is triggered by a weighing device (14), mounted under the upstream end of this device (2), on a movable part of the bar (10).

The device (13) gradually pushes a quantity of fibers onto the weighing device (14): when the desired weight is reached, the weighing device (14) gives a signal to the motor, not shown, which actuates the belts (66). This start-up allows * to drive this determined bundle of fibers (3) downstream by the action of the comb (69).

Simultaneously, the device (13) is inactivated so as to no longer bring fibers to the weighing device (14).

The ply (9) is also retained upstream of the weighing device (14) by a folded sheet (15) which is raised when the device (2) is stopped.

Under the downstream end of the device (2), a horizontal sheet of triangular shape (16) is placed point upstream and base downstream so as to cause the bundle of fibers (3) to lay flat, initially folded in half on the bar (10), maintaining a perpendicular orientation of the fibers in the direction of advancement.

The action of the device (2) stops when the bundles of fibers (3) are taken up at their ends by two pairs of holding and transport belts (17) and (18). Each pair of belts is made up of an upper belt stretched between an upstream unshielded pulley (19) and a downstream drive pulley (20) and an identically mounted lower belt. On this trajectory, each of these belts is also in contact with a pressure roller (21), horizontal and perpendicular to the belt, in which a groove is machined corresponding to the shape of the belt (17 or 18). A pushing means makes it possible to exert a force of one roller on the other.

The twisting device (4) is installed in the interval between these two pairs of belts (17) and (18) and upstream of the two pressure rollers (21). As shown in FIGS. 3 and 4, this twisting device comprises a rotary chassis (22), two twisting elements (23), eccentric, arranged symmetrically with respect to the axis of the chassis (22) and integrated into it ci, as well as transmission elements (24), of the gear type, the ratios of which print at least one full rotation or an entire number of turns to the twisting elements (23) each rotation of the chassis (22).

The frame (22) has two parallel walls (25), of oblong shape, held at a distance by spacers (26). One of the walls (25) is fixed on one end of a horizontal axis (27), perpendicular to the wall (25), while the other end of the axis (27) is held in a bearing (28 ), carried by a support (29). This axis (27) is therefore perpendicular with respect to the device for transporting flax packs (3), the direction of transport of which is indicated by the arrow
(30) in Figures 1 & 2. A chain sprocket (31) is fixed to the end of the axle (27): a chain (32) is wrapped around this sprocket.

The oblong walls (25) are provided with two notches (33) arranged symmetrically with respect to the axis (27) which end by widening towards the end of the walls (25).

The two twisting elements (23) are hollow gears (34) provided with a "gripping" opening the size of a handful of fibers (3). Each of these twisting elements (23) has on its two flanks a concentric shoulder (35) interrupted at the level of the "gripping" opening. The shoulders (35) of a twisting element (23) are embedded in the sides inside the walls (25) in larger circular housings (36), also interrupted at the notches (33) which serve as guides in the rotation of the twisting elements (23): it follows that the twisting elements (23) are embedded in the chassis (22).

In each twisting element (23), the holding element of the bundle of fibers consists of a point (37) arranged radially and oriented towards the middle of the gripping opening. This point prevents the twisting element (23) from sliding around the bundle of fibers (3).

The transmission (24) which actuates the twisting elements (23) comprises four pinions (38) placed on axes perpendicular (39) to the walls (25) and mesh simultaneously in pairs on one side with the twisting element (23 ) and on the other side, with the central pinion (40). The four pinions (38) are therefore meshed on a single central pinion (40), fixed on an axis (41) which is housed inside and outside the chassis in bearings (42). These bearings are located in a tube (43), which is fixed on the support (29) above and passes freely through the wall (25). The axis (41) carries on its outer end a chain sprocket (44) over which passes a chain (45).

The chains (32) and (45) are driven by chain sprockets actuated by a motor not shown so that a half rotation of the chassis (22) in the direction indicated by the arrow (46) in FIG. 4 is synchronized with a double rotation of the central pinion (40).

The set of pinions (38) and (40) as well as the twisting elements (23) having the same number of teeth, these twisting elements (23) also perform a double rotation.

Twisting takes place as follows:
In the initial position, shown in Figures 3 and 4, the frame (22) is oriented so that a notch (33) is placed upstream and the other downstream on the path of the bundle of fibers. The twisting elements (23) are in a position which places their gripping opening (34) in the notches (33) of the walls (25).

A bundle of fibers (3), brought by the conveyor belts (17) and (18) and held by these same belts at its ends, penetrates through the notches (33) of the walls (25) in the gripping opening (34) of the twisting element (23) located upstream.

While the frame (22) rotates 180, the bundle of fibers follows this trajectory and simultaneously undergoes by the twisting elements (23) a rotation on itself which gives it a twist. Once this half rotation is complete, the twisting element (23) is located downstream with its gripping opening (34) in the notch (33) and the now twisted handle (6) can continue its path downstream in the belts (17) and (18) leaving the twisting element (23) through the gripping opening (34).

To maintain the ends of the handle (3) in the belts (17) and (18) during the half rotation of the chassis (22), a path which passes through the two strands in contact with the belts (17) and (18) first below a roller (47) located substantially at the height of the twisting element (23) in its upstream position, then on a roller (48) whose axis is concentric with the axis of rotation of the chassis and whose radius equals the distance between the center of rotation of the chassis and the center of the twisting element (23) Finally, the two strands pass under a roller (49) located at the height of the twisting element in position The rollers (47) and (49) are advantageously mounted on a system with tensioner not shown.

To avoid partial or total untwisting of the twist, two other pairs of conveyor belts (50) and (51), located between the two pairs of belts (17) and (18), hold the twisted part of the handle ( 6) as soon as it leaves one of the twisting elements (23): these belts are stretched respectively upstream between the rollers (52) and (53), and downstream between the rollers (55) and (56). The two strands in contact with these belts (50) and (51) also pass between the pressure rollers (21), in grooves.

At the downstream end of the belts (17), (18), (50) and (51), the twisted handle (6) is taken up in two places between two pairs of belts (57), which pass over wheels (58 ), (59) and (60).

The three wheels (58), (59) and (60) in contact with the belts (57) are arranged so that the wheel (59) is substantially at a higher position than the other two wheels (58) and (60 ). The wheel (60), animated by a pendular movement controlled according to the arrows 61 of FIG. 1, gives an identical movement to the downstream part of the belts (57) which thus juxtapose the twisted handles (6) in several superimposed layers to form a package (7) in a compartment (62) of the endless transport device (5). The means for actuating the ends of the belts (57), as well as the drive of the wheels (58), (59) and (60 ) are known and are not shown in the figure for simplicity.

Downstream of the rollers (21), the belts (50) and (51) transport the twisted handles (6) while the pressure exerted by the rollers (21) ensures the stabilization of the twist.

As soon as a compartment (62) is full, the transport device is switched on so that the bundle of twisted handles (7) is linked by the tying device (8), the known construction of which is not described here. . The packages (7) are optionally pressed together or separately, before or after the binding is carried out.

The device described above is * a simple construction; it allows quick and mechanical twisting * a bundle of fibers to obtain a twisted handle as durable as a manually twisted handle. The route shown in Figures 1 and 2 allows you to quickly condition a linen tablecloth in twisted handles with a minimum of staff.

The invention is in no way limited to the embodiment described above. Within the framework of the invention, several changes can be added to the described embodiment, inter alia, as regards the shape, arrangement and number of parts which are used for the realization of the invention.

In particular, the number of twisting elements is not limited: there may be one or more than two. At least one is required.

The twisting elements are not necessarily mounted on a rotating chassis. They can for example be moved by an endless transport device which accompanies the handles during twisting.

The separation of the sheet into a bundle of fibers is not necessarily carried out mechanically, nor necessarily carried out as described. A worm can also be used.

The number of rotations of the twisting element per half-turn of the rotary chassis is given above only as an example: only one rotation is sufficient or more than two depending on the number of turns that we want to give to the handful of fibers.

In particular, the twisting element does not necessarily have to take the bundle of fibers between the two held ends of the handle. For example, the twisting element can work on one end of the bundle of fibers while the other end is held by a set of belts.

The device for forming a bundle of fibers is not necessarily produced using belts carrying combs: a screw system, for example, can also be used.

The formation of twisted handle packages is not necessarily carried out using conveyor belts driven by a pendulum movement: a device of fixed belts and animated conveyor belts makes it possible to carry out the same work.

If necessary, movable forks and forks can be mounted downstream of the rotating frame to force the twisted handles out of the twisting element through the gripping opening.

Claims (15)

1. Machine for twisting linen handles (6), characterized in that it comprises a twisting device (4) comprising at least one twisting element (23) driven in a rotational movement on itself by means (38 to 45) and provided with a gripping opening (34) through which a bundle of untwisted fibers is introduced and in that it comprises means (17,18) for holding the bundle of fibers (3) taken in this twisting element (23) at a non-zero distance so that this twisting element twists the bundle of fibers. 2. Machine according to the preceding claim, characterized in that the twisting element (23) provided * a gripping opening (34) is a pinion comprising a recess in its central part opening over a portion of its circumference. 3. Machine according to one of the preceding claims, characterized in that the twisting element (23) has a point (37) arranged radially and oriented towards the middle of the gripping opening (34) 4. Machine according to one of the preceding claims, characterized in that the twisting device (4) comprises a rotary frame (22) in which the twisting element (23) is mounted eccentrically and comprises a transmission (24) which ensures the rotation of the twisting element (23) on itself by an integer number of turns per half turn of the chassis. 5. Machine according to one of the preceding claims, characterized in that the twisting device (4) comprises two twisting elements (23) placed symmetrically with respect to the axis of the chassis. 6. Machine according to the preceding claims, characterized in that the transmission (24) of the twisting device comprises a central pinion (40) placed concentrically with the axis of rotation of the chassis and means (41-45) for driving this central pinion and in that it comprises at least two pinions (38) per twisting element (23) which mesh simultaneously on one side with the central pinion (40) and on the other with the twisting element (23). 7. Machine according to one of the preceding claims, characterized in that it comprises a means of transport (17 to 20) of the twisted handles so as to accompany the movement of the bundles of fibers during their twisting in the twisting element. and on the trajectory of it. 8. Machine according to claim 1, characterized in that it comprises means (21 and / or 50,51) to avoid untwisting of the twisted handle. 9. Machine according to the preceding claim, characterized in that the means (21 and / or 50.51) for preventing the twisting of the twisted handle comprise means (50.51) for holding the twisted part of the handles (6) in at least two places. 10. Machine according to the preceding claim, characterized in that the means (50,51) for holding the twisted part of the handles (6) in at least two places comprise two pairs of endless conveyor belts (50,51) acting together and placed one above the other. 11. Machine according to claim 8, characterized in that the means (21 and / or 50,51) for preventing the twisting of the twisted handle comprise pressure elements (21) which exert pressure at least on the twisted part of the handles. 12. Machine according to claim 1, characterized in that it comprises at least two transport devices (17 to 20 and 49 to 56), the first (17 to 20) for bringing the bundles of non-twisted fibers (3) into the twisting device (4) and the second to take the twisted handles (6). 13. Machine according to one of the preceding claims, characterized in that it comprises an automatic packaging device (5) of the twisted handles comprising a transport device (57 to 60) for bringing the handles (6) to a juxtaposition device in several superimposed layers. 14. Machine according to the preceding claim, characterized in that the juxtaposition device in several superimposed layers comprises an endless transport element on which the packets (7) of handles are formed and a binding device (8) for placing a link on the previously formed package. 15. Machine according to claim 1, characterized in that it simultaneously comprises a device (2) for mechanically separating a tablecloth of dyed linen (9) in a bundle of untwisted fibers (3).