EP0763613B1 - Device to select and feed weft yarns for a loom - Google Patents

Description

Device for selecting and delivering weft threads to one Entry organ for a weaving machine with at least one a weft feeder associated with a own drive motor connected to a control unit movable between a rest position and a delivery position is.

In known devices of the type mentioned (EP-A 0 362 089, EP-A 0 478 986, EP-A 0 461 524) become the feeders transferred to the delivery position if the one you are guiding Thread should be entered as a weft. They remain in this delivery position until the end of the weft entry, after which they are returned to the resting position, in which they remain until the one they lead Thread should be entered again as a weft.

The invention has for its object the stress of weft threads to reduce weft insertion.

This object is achieved in that the control unit means contains to the feeder while entering a weft thread guided by him from the delivery position in at least one between the delivery position and the rest position to transfer the intermediate position.

The invention is based on the knowledge that the stress of a weft thread reduced during the weft insertion can be if the deflection of the weft in the area the thread guide of the thread feeder is low. This will in the area of the thread guide, the friction is lower, so that the Risk of weft breakage is reduced. The least an intermediate position is therefore chosen so that the weft while entering in the area of the feeder concerned undergoes the least possible deflection.

Fig. 1

zeigt eine Ansicht einer schematisch dargestellten erfindungsgemäßen Vorrichtung,

Fig. 2

eine Ansicht der Vorrichtung in Richtung des Pfeiles F2 der Fig. 1,

Fig. 3 und 4

Ansichten entsprechend Fig. 1 mit anderen Positionen des Zubringers,

Fig. 5

eine teilweise geschnittene Ansicht ähnlich Fig. 2 einer spiegelsymmetrischen Anordnung von Moduln einer erfindungsgemäßen Vorrichtung,

Fig. 6

einen Schnitt entlang der Linie VI-VI der Fig. 5 und

Fig. 7

die Einzelheit F7 der Fig. 6 in größerem Maßstab.

Further features and advantages of the invention result from the following description of the exemplary embodiments shown in the drawing.

Fig. 1

shows a view of a schematically illustrated device according to the invention,

Fig. 2

2 shows a view of the device in the direction of arrow F2 in FIG. 1,

3 and 4

1 with other positions of the feeder,

Fig. 5

2 shows a mirror-symmetrical arrangement of modules of a device according to the invention,

Fig. 6

a section along the line VI-VI of Fig. 5 and

Fig. 7

the detail F7 of Fig. 6 on a larger scale.

1 to 4 is a single module (1) of a device for selecting and delivering weft threads that are shown a large number of similar modules (1) exist. Every module (1) contains a thread feeder (3), the end of which with a Eye (21) is provided, in which a weft thread (30) is guided is.

Each module (1) contains a drive motor (4) for the thread feeder (3). The drive motor (4) is directly via an eccentric drive (6) with that designed as a round rod or needle (11) Thread guide (3) connected. On the shaft (5) of the drive motor (4) which is transverse to the longitudinal axis of the thread feeder (3) is aligned, is parallel to the thread feeder (3) Crank (9) arranged non-rotatably. The crank (9) is with one Provide crank pin (10) on which the eye (21) opposite end of the thread feeder (3) is mounted. The rod or needle (11) of the thread feeder (3) is in one Guide (12) guided, which has a longitudinal bore (13). This The guide (12) is as close as possible to the one with the eye (21) End of the thread feeder (3) and arranged around one to the shaft (5) parallel axis (14) rotatable.

Each module (1) has a plate (16) as a supporting structure, on the back of the drive motor by means of only indicated Screws (22) is attached. The plate (16) is in the area of the eccentric drive (6) with a recess (17). The thread feeder (3) and its guide (12) are on the side of the plate opposite the drive motor (4) (16). The guide (12) is with its axis (14) through the plate (16) pushed through and on the opposite side secured with a securing element, for example one Clips (23). As can be seen from Fig. 1, 3 and 4, the Plate (16) has a trapezoidal base, which is from the area of the drive motor (4) to the area of the guide (12) tapered.

The masses of the parts to be moved by the drive motor (4), namely the crank (9) and the thread feeder (3) and the Guide (12) are relatively small, so that correspondingly low Mass inertia forces for adjusting the thread feeder (3) are to be overcome. This will result in higher working speeds and / or the use of relatively low-power drive motors (4) possible.

The maximum angle of rotation of the motor shaft is by means of stops (25, 26) limited. These attacks exist in the illustrated Embodiment of projections (25, 26) of the recess (17), the maximum angle of rotation of the crank (9) and thus also limit the shaft (5) of the drive motor (4). The tabs (25, 26) are arranged such that in the rest position (Fig. 1) and in the delivery position (Fig. 3) the crank (9) and the rod or needle (11) of the thread feeder (3) with each other align, i.e. the shaft (5) and the crank pin (10) in a through the axis of the rod or needle (11) Level.

In a modified embodiment, adjustable stops provided, for example in the form of set screws, which are attached to the plate (16) and which the angle of rotation limit the crank (9).

The drive motors (4) of the individual modules (1) are connected to one electronic control unit (20) connected which determines when and how, i.e. at what speed, the thread feeder (3) from the rest position (Fig. 1) to the delivery position (Fig. 3) and possibly to an intermediate position (Fig. 4) are moved. The control unit (20) can feed the thread (3) at any time and regardless of the position of others Weaving machine parts, such as the comb shutter drive, the shaft drive or other drives, in the desired position bring. This makes it possible to move the thread feeder (3) Depending on the type of weft, for example to choose or cancel a weft entry or the thread feeder (3) during a stop or during a loom downtime in any position bring to.

In a preferred embodiment it is provided that the Drive motors (4) are designed as stepper motors, which from the control unit (20) for the desired movement suitable pulse sequence or number of pulses is supplied. This Pulse sequence can be chosen so that the crank (9) in the Rest position to the stop (25) and in the delivery position the stop (26) is pressed so that two stable positions can be obtained for the thread feeder (3). However, preference is given provided that the pulse sequence is designed so that the crank (9) is not at the stop in the respective end positions (25 or 26) is present. This is due to the number of Steps possible with which the drive motor is rotated. The Thread feeder (3) can be in an adjustable rest position or delivery position can be held by the drive motor (4) a so-called holding current is applied. This holding current is chosen in such a way that the positioning of the thread feeder (3) not from vibrations of the weaving machine or influenced by forces of the weft thread exerted on it becomes. If the crank (9) and the rod or needle (11) of the thread feeder (3) in the rest position and / or in the delivery position is at least approximately aligned with one another, from a weft thread (30) onto the thread feeder (3) forces practically not transferred to the crank (9), so that only a relatively low holding current is required is.

Because the eccentric drive (6) at the beginning of its movement from the rest position, i.e. in the direction of arrow (P1) of FIG. 1, as well as from the infeed movement, i.e. Arrow direction (Q) in Fig. 3, only a relatively small movement component in the longitudinal direction of the thread feeder (3) results in a relatively gentle start of the movement of the feeder (3), so that the weft thread (30) is spared and the risk of weft breakage is reduced. To reinforce this effect can be provided that the control unit (20) the pulse sequence with a variable frequency to the drive motor (4) emits, so that a slow start of the drive motor (4) is obtained.

When the thread feeder (3) is in its rest position, after a certain time or for example provided after a certain number of strokes of the sley be that the crank (9) with the stop (25) to the system is brought so that a reference position for the control unit (20) the motor shaft (5) is determined. Such Reference position can also be obtained with the help of a detector be, for example with the help of a proximity switch.

In another embodiment it is provided that the Provide the shaft (5) of the drive motor (4) with an angle detector is connected to the control unit (20). The Control unit (20) can then control the controllable drive motor (4), which in this case need not be a stepper motor, until it has reached the specified angular position. Also in this case it is possible to use a drive motor (4) variable speed so that each starting at a reduced speed. The drive motor (4) can be operated by the control unit (20). be supplied with a current of variable frequency.

In the rest position (Fig. 1), the thread feeder (3) steers one between a stationary thread guide, for example one stationary eye (33), and a shed (34) extending Weft thread (30) such that it is outside the range of motion an entry element (31), in particular one Gripper (32), as shown schematically in Fig. 1. In the infeed position (Fig. 3) the thread feeder (3) is such adjusted that the weft thread (30) then in one area runs in which it is gripped by the entry member (31) is, for example the gripper (32). After the weft (30) has been taken by the entry member (31), the Thread feeder (3) can be returned to its rest position. In the invention shown in Fig. 4 However, it is provided that the thread feeder (3) brought into an intermediate position during the shot entry in which the weft thread (30) in the area of the eye (21) of the thread feeder (3) is deflected as little as possible. Thereby the friction is reduced in the area of the thread eye (21), so that the risk of weft breakage is reduced. Here can also be provided that the thread feeder (3) with a steady movement is shifted so that the friction in the thread eye (21) is as small as possible, the thread feeder (3) can change its position for this purpose. Also this constant adjustment is due to an appropriate interpretation the control unit (20) can be implemented. The start of the Intermediate position also has an advantage if the following Weft entry of the same weft thread entered again shall be. In this case the thread feeder (3) needs only a short way to his delivery position to cover.

In the event of a weft break, it is advisable to use the thread feeder (3) to move to a position where threading a weft is simplified. For this purpose it is provided that each module (1) is assigned a switch (48) which is connected to the Control unit (20) is connected. By operating the switch (48) a signal is given to the control unit (20) on the basis of the control unit (20) of which the associated thread feeder (3) by turning the drive motor (4) accordingly brings the threading position. The control unit (20) delivers for this threading position a corresponding holding current to the Drive motor (4) if this is a stepper motor. Means operating the switch (48) again Thread feeder (3) is in its original position brought.

As already mentioned, there is a device for Selection and delivery of weft threads from a variety of Modules, as shown in Fig. 5 to 7. For reasons For clarity only five such modules (1A to 1E), which is of course an essential in practice larger number of modules can be provided. Every single one these modules (1A to 1E) correspond to those described above Embodiment designed, i.e. he owns a drive motor (4A to 4E) and an eccentric drive for a thread feeder (3A to 3E), each in a guide (12A to 12E) by means of a rod or needle (11A to 11E) is. These elements are arranged on plates (16A to 16E) as was explained with reference to FIGS. 1 to 4. The Thread feeders (3A to 3E) lie in a common plane. Around the individual thread feeders (3A to 3E) as close together as possible to be able to arrange the modules (1A to 1E) in two rows (40, 41) with respect to the common plane of the thread feeders (3A to 3E) mirror images of each other and offset arranged to each other. The common plane can be flat or be spatially curved (arched). Your plates (16A to 16E) are arranged between two holding plates (42, 43), to which they are attached with screws (46). This Plates (42, 43) are connected to one another by transverse webs (44) (Fig. 6). The plate (43) is by means of screws (47) Machine frame (45) held.

In the exemplary embodiment, the thread feeders (3A to 3E) between their rest position and their delivery position an arcuate movement (27), as shown in Fig. 7 is. To ensure that the thread feeder (3A to 3E) not hindering each other despite their dense succession, it is provided that the arcuate movements (27) all thread feeders (3A to 3E) run parallel to each other. For this purpose it is provided that the direction of rotation on one side arranged drive motors (4C, 4E) opposite to the direction of rotation the drive motors arranged on the other side (4A, 4B, 4D). The recesses (17A, 17B, 17D) mirror-symmetrical to the opposite recesses (17C and 17E). Of course you can same plates (16) are used, only then the arrangement of the drive motors (4) and the longitudinal guides (12) is interchanged on the bases of the plates (16).

The individual modules (1A.) Attached to the plates (42, 43) to 1C) can individually on the plates (42, 43) in each other different positions can be attached aligned. It is also possible to attach the plates (42, 43) to the machine frame (45) aligned and aligned in a common Position on the machine frame (45). Since the device consists of a large number of individual modules, it is possible to use the device quickly and easily with additional or fewer modules (1) accordingly enlarge or reduce the application. In addition, a single module can easily be damaged be exchanged in total. Because the drive motors (4) too in the opposite arrangement (Fig. 5) on the outside are arranged, they are easily accessible and therefore easily replaceable in the event of a defect.

As shown in FIGS. 6 and 7, the thread feeders are located (3A to 3E) in the delivery position in adjacent positions. It is of course possible to do the individual modules to be aligned so that all thread feeders (3A to 3E) have one essentially lying on the same axis or even in take delivery position located at the same point.

Because the movement of the thread feeder (3) is independent of the movement other loom drives, the advantage is given that, for example, after a thread break the one in question Thread feeder (3) are brought into the infeed position again can with other machine drives without this movement synchronize, i.e. other machine drives forward or to move back. Above all, there is the advantage that only relatively small moving masses are available, so that high working speeds and thus a high weaving machine speed is feasible.

By a suitable control of the drive motors (4) is also given the advantage that the rest position of the thread feeder (3) can be changed without mechanical adjustments must be made. A corresponding setting can be done via the control unit (20), for example is provided with an input unit.

In the illustrated embodiments, the thread feeders are (3) with thread eyes (21). Another one Embodiment provides that the thread feeder (3) with Thread clamps are provided, as also by the State of the art is known.

In a modified embodiment, the guides (12) the thread feeder (3) held with rubber-elastic bearings, see above that the axis (14) is omitted. In another execution provided that the thread feeder (3) is elastic in the transverse direction are supported.

In addition, it is possible to use a thread feeder (3) rectilinear movement between the rest position and the delivery position to move if provided by other means is that the transverse movement of the eccentric drive with respect to back and forth movement of the thread feeder (3) compensated becomes. This can happen, for example, that the Thread feeder (3) consists of two parts, which are connected by a joint are interconnected, one parallel to the motor shaft (5) Has axis of rotation.

Claims (2)

1. A device for selecting and feeding weft threads (30) to an insertion element (31) for a loom, having associated with a weft thread at least one feeder (3), which is movable between a rest position and a feed position by means of its own drive motor (4) connected to a control unit (20), characterised in that the control unit (20) contains means for moving the feeder (3) out of the feed position into at least one intermediate position between the feed position and the rest position during insertion of a weft thread (30) guided by the feeder.
2. A device according to claim 1, characterised in that the control unit (20) contains means for continuously shifting the position of the feeder (3) in a direction from the feed position to the rest position to adapt to a changing running direction of the weft thread (30).

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