HK1191071B - Dobby loom and corresponding weaving method - Google Patents

Description

Rapier weaving machine and corresponding weaving method

Technical Field

The invention relates to a rapier weaving machine, in particular a tape weaving machine, having a shedding device with a rapier weaving device and heald frames, wherein the heald frames are connected to linear motors, respectively, and by means of the control thereof, a movement of the heald frames from an upper maximum position to a lower maximum position and a reversing movement can be carried out, and wherein the weaving machine has a weft insertion device for introducing one or optionally a plurality of weft threads into a warp shed. The invention also relates to a corresponding textile method.

Technical Field

Shedding devices for weaving machines with rapier devices and heald frames are known from a large number of documents. From WO-A-98/24955A weaving machine is known in which A pick-up element of the weaving machine, which has for example A heald frame, for picking up warp threads is clamped between two springs. The pick-up element is pivoted and the fixing device can hold this pivoting for a certain time and thus form a shed during the weft insertion. The shed-forming device is further improved in WO2008/037106a 1.

Such a shed-forming device has proven to be entirely advantageous, in particular for operation at high rotational speeds, that is to say at high weaving speeds, in particular in order to limit the energy required.

Such a shed forming device is of course limited in its flexibility. On the one hand-apart from the optional middle shed position, only the lower shed position and the upper shed position, i.e. the stops of the fixing means, are possible. Furthermore, the movement takes place only once when the shed-forming device is activated as a result of the heald frames being released from the stationary magnets, more or less predetermined, that is to say without great possibility of detailed control movements.

Disclosure of Invention

The invention is based on the object of flexibly influencing the weft insertion in a rapier weaving machine by means of a device connected to the rapier. For example, a weft color alternating device regularly or irregularly spaced on the tape edge or a device for producing loops of weft of different sizes. The invention is based on the object of providing an advantageous weaving method which is advantageous for corresponding use.

This object is achieved according to a first aspect of the invention by a rapier weaving machine according to claim 1. The inventive measures result in an unexpectedly high flexibility in the first place. By configuring the control device for controlling the linear motor such that a predefined position of the heald frames between an upper maximum position and a lower maximum position can be controlled at a predefined time, it is possible to use the heald frames more flexibly than in WO2008/037106a1, for example. In order to increase the weaving speed, the shed can be made smaller, i.e. the difference between the upper and lower shed is smaller than the maximum difference, for example. The control means are, in principle, capable of very quickly "completely" constructing the shed and then possibly remaining for a certain time. The weft insertion device is therefore more likely to introduce the weft thread, preferably by means of a weft needle, alternatively also by means of a clamping device or a pneumatic device. Furthermore, unlike the conventional case, the upper shed position or the lower shed position of a warp thread can be moved in different "middle shed positions", so that different weft threads should be introduced simultaneously — independently of whether a weft thread alternation is still present. The "middle shed positions" do not necessarily all have to be identical, but can-programmably-differ from each other, for example in relation to whether they are occupied by an upper shed or a lower shed position. This brings certain advantages: for example, to protect the warp yarns. By continuously determining the position of the individual heald frames, the control device is designed such that it essentially controls the moment of the movement of the heald frames, preferably the start of the movement individually. It is particularly advantageous if the linear motors in each case require the greatest power consumption at the start of movement, since the moment of movement start can be separated and at least not all linear motors simultaneously require the highest energy input.

By being able to control the heddle frame at a predetermined moment in time at a predetermined position between a maximum position above and a maximum position below, completely different new possibilities exist. According to claim 2, it can also be provided that the weft insertion device is operatively connected to a plurality of heald frames of the rapier device. In this case, one of the color control devices is preferably assigned to each heald frame. The selective introduction of the respective weft thread can thus be controlled by the movement of the heddle frame. This measure is particularly advantageous, therefore, if the weft insertion device has a plurality of actively controlled weft thread feeding means, by means of which a predetermined quantity of the respective weft thread can be fed when the corresponding color control means is selected for the insertion of a weft thread.

Another possibility is obtained for controlling the heddle frame at any position between the upper maximum position and the lower maximum position at a given time: creating loops of weft yarn on the belt edge that are freely selectable in size and distance. The weft thread is here placed around conically shaped "forks" which are respectively operated by the rapier and are used at the appropriate time. By means of the different strengths of the immersion of the fork in relation to its conical design, loops of weft thread of different sizes can be produced.

Advantageously, the control device has a regulating device, preferably a PID controller, by means of which the instantaneous setpoint position for the movement of the individual heald frames is determined. The pulling deviation, i.e. the difference between the instantaneous actual position and the instantaneous target position of the individual heald frames of the rapier device, can then be adjusted. The adjusting device is preferably designed such that the pulling deviation can be substantially eliminated at the time, i.e. at the predefined position, in order to reach the predefined position at the predefined time.

According to a second aspect of the invention, the object is accordingly achieved by a method as claimed in claim 5. Advantageous embodiments of the method according to the invention are given in claims 6 to 8.

The dimensions, shape design, material use and technical solutions of the components used according to the invention, which were mentioned above and claimed and described in the following examples, are not subject to any special exceptions, so that the selection criteria known in the respective field of application can be applied without limitations.

Drawings

Embodiments of the invention are further described below with reference to the accompanying schematic drawings in which:

fig. 1 is a principal construction of an application of the invention with a weft insertion device, in which color control devices are respectively assigned to heald frames and the selective insertion of corresponding weft yarns is controlled by the movement of the heald frames;

FIG. 2 is a movement curve of a textile element corresponding to the use according to FIG. 1 in this case, in which a first weft thread color is introduced into the shed and a second weft thread color is incorporated into the selvedge;

FIG. 3 is a graph of the movement of a textile element in the case of color alternation, corresponding to the application according to FIG. 1, wherein a first weft color is picked and a second weft color is fed;

FIG. 4a shows the introduction of a first weft yarn color;

FIG. 4b shows a state shortly before the second weft yarn color is fed;

FIG. 4c shows the weft needle at the left turn;

figure 4d shows the weft needle shortly before re-entry into the shed,

fig. 4e shows the introduction of a second weft yarn color.

Detailed Description

A particularly advantageous embodiment of the invention is shown in fig. 1. Fig. 1 shows the essential elements of a rapier weaving machine with weft insertion devices, wherein the individual color control means, in the embodiment shown, a weft selection device 18 for a first color and a weft selection device 20 for a second color are assigned to the heald frames 4 and 6 in each case, and the movement of the heald frames 4 controls the selective insertion of the corresponding weft thread. The further heddle frames 8 and 10 correspond here customary to the structure of the shed. The other elements of the rapier weaving machine, i.e. the reed 28 and the fabric 26 being stopped and the warp yarns in the upper shed 22 and the warp yarns in the lower shed 24 represent here other conventional elements of known rapier weaving machines. This is possible only if the weaving machine has a control device for controlling the linear motor of the rapier, which is designed in such a way that a predefined position of the heald frame between a maximum position above and a maximum position below can be controlled at predefined times. In this embodiment, the rapier weaving machine comprises sensor means by means of which the position of each heddle frame 4, 6, 8, 10 can be continuously detected.

In the present exemplary embodiment, the weft insertion device is also associated with a plurality of actively controlled weft thread supply means 30, 32, by means of which a predetermined quantity of the respective weft thread 40, 42 can be supplied when the respective color control means 18, 20 is selected for the insertion of the weft thread 40, 42.

The control device has an adjusting device, preferably a PID controller, by means of which the instantaneous setpoint position for the movement of the individual heald frames 4, 6, 8, 10 can be determined and the drag deviation, i.e. the difference between the instantaneous actual position and the instantaneous setpoint position of the individual heald frames of the rapier device, can be adjusted. The adjusting device is in this embodiment configured such that the pulling deviation substantially disappears at the time, i.e. at the predefined position.

Fig. 2 shows a phase profile corresponding to the use according to fig. 1, i.e. a movement profile of the textile element in one case as a function of the angle of rotation (phase angle) of the main axis, wherein a first weft yarn color is introduced into the shed 22, 24 and a second weft yarn color is incorporated into the selvedge of the fabric 26. In the figure, the main phase points are indicated, namely phase point a "reed stop" and phase point B "weft needle entry into the shed".

In fig. 3, the phase curve corresponding to the application according to fig. 1 is shown, i.e. the movement curve of the textile element in one case as a function of the angle of rotation (phase angle) of the main shaft, wherein weft threads of a first weft thread color are fed in and weft threads of a second weft thread color are picked out. The main phase points, i.e. phase point a "reed stop", phase point B "weft needle into shed", phase point C "weft of the first weft color is fed" and phase point D "weft of the second weft color is picked" are indicated in the figure.

The process of alternating weft insertion and weft in figures 4a to 4e is illustrated below: fig. 4a shows the introduction of a first weft yarn color. The weft yarn 40 of the first weft yarn color is picked up through the hole at the tip of the weft needle 14. The weft yarn 42 of the second weft yarn color is not picked up by the weft needle 14 but remains in the region of the left side band edge. FIG. 4b shows the condition shortly before weft yarn 42 of the second weft yarn color is fed. The weft needle 14 is moved away from the shed. The color control needle 20 of the second weft color is placed in its upper position, the weft yarn 42 of the second weft color contacts the weft needle 14 from below and jumps into the hole at the tip of the weft needle 14 at the next moment. Fig. 4c shows the weft needle 14 at its turn to the left. The weft yarns of both weft yarn colors 40, 42 are located in the holes at the tips of the weft needles 14. Fig. 4d shows the weft needle 14 shortly before re-entering the shed. The color control needle 18 of the first weft color is placed in a position below it, whereby the weft thread 40 of the first weft color jumps out of the hole at the tip of the weft thread needle 14. The weft yarn 42 of the second weft yarn color remains in the hole at the tip of the weft needle 14 because the associated color control needle 20 remains in a position above it. Fig. 4e shows the introduction of weft yarn 42 of the second weft yarn color. The weft yarn 42 is picked up through a hole at the tip of the weft needle 14. The weft thread 40 of the first weft thread color is not taken up by the weft thread needles 14 but remains in the region of the left side band edge.

This embodiment has the advantage that, by moving the heald frames of substantially identical shape and controlling a specific control process of the rapier weaving machine (apart from the shedding), the weaving process can be carried out according to the invention by means of a control device for controlling the linear motors in such a way that at predetermined times predetermined positions of the heald frames between an upper maximum position and a lower maximum position are controlled and the position of the heald frames is continuously detected by means of sensor devices.

List of reference numerals

4 heald frame for a first colour

6 heald frame for a second colour

8 heald frame for shed formation

10 heald frame for shed formation

14 weft needle

18 color control device for a first color

20 color control device for a second color

22 warp yarns in the upper shed

24 warp yarns in the lower shed

26 Fabric

28 loom reed

30 active first color yarn feeding device

32 active yarn feeding device for second color

40 weft yarns of the color of the first weft yarn

42 weft of the second weft color

Reed stop phase point

B phase point of weft needle entering shed

C feeding phase points of weft yarns of the first weft yarn colour

D picking out the phase point of the weft yarn of the second weft yarn color

Claims (7)

1. Weaving machine with a shedding device for forming a warp shed, having a rapier device and a plurality of heald frames (4, 6, 8, 10), wherein the heald frames (4, 6, 8, 10) are connected with linear motors, respectively, by means of the control of which movements of the heald frames (4, 6, 8, 10) from an upper maximum position to a lower maximum position and vice versa can be carried out, and having a weft insertion device for inserting one or optionally a plurality of weft threads into the warp shed (22, 24),

wherein the weaving machine has a control device for controlling the linear motors, which control device is designed to enable the heddle frames (4, 6, 8, 10) to be controlled at predetermined times in predetermined positions between the upper maximum position and the lower maximum position,

wherein the control device has a sensor device by means of which the position of each heald frame (4, 6, 8, 10) can be continuously detected,

characterized in that the weft insertion device with a plurality of color control devices (18, 20) is operatively connected to a plurality of heald frames (4, 6) of the rapier device for the selective insertion of weft threads, each color control device (18, 20) being assigned to the heald frame (4, 6) for the selective insertion of weft threads in each case and being able to control the selective insertion of the corresponding weft thread (40, 42) by means of the movement of the heald frame (4, 6) for the selective insertion of weft threads.

2. Weaving machine according to claim 1, characterized in that the weft insertion device has a plurality of actively controlled weft feeding means (30, 32), by means of which weft feeding means (30, 32) a predetermined amount of a respective weft thread (40, 42) can be fed when the corresponding color control means (18, 20) is selected for weft insertion.

3. Weaving machine according to claim 1 or 2, characterized in that the control device has an adjusting device, by means of which the instantaneous setpoint position for the movement of the individual heald frames (4, 6, 8, 10) is determined and a traction deviation, that is to say the difference between the instantaneous actual position of the individual heald frames (4, 6, 8, 10) of the rapier device and the instantaneous setpoint position, can be adjusted, wherein the adjusting device is set up such that the traction deviation substantially disappears at the time, that is to say at the predefined position.

4. Weaving machine according to claim 3, characterized in that the regulating device is a PID controller.

5. Weaving method with the aid of a weaving machine according to one of claims 1 to 4, wherein the weaving machine has a shed-forming device for forming a warp shed (22, 24) with a rapier device and a plurality of heald frames (4, 6, 8, 10), wherein the heald frames (4, 6, 8, 10) are connected in each case with a linear motor, the movement of the heald frames (4, 6, 8, 10) from an upper maximum position to a lower maximum position and vice versa being able to be carried out by control of the linear motors, and a weft insertion device for introducing one or optionally a plurality of weft threads (40, 42) into the warp shed,

wherein the weaving process is carried out by means of a control device for controlling the linear motor in such a way that the heald frames (4, 6, 8, 10) are controlled at predetermined times at predetermined positions between the upper maximum position and the lower maximum position,

wherein the position of each heald frame (4, 6, 8, 10) is continuously detected by means of a sensor device,

characterized in that the movement of one of the heald frames (4, 6) for the selective weft insertion is controlled in order to selectively insert the corresponding weft thread (40, 42), wherein the weft insertion device is operatively connected to a plurality of heald frames (4, 6) for the selective weft insertion of the rapier device in such a way that each of the color control means (18, 20) is assigned to a respective heald frame (4, 6) for the selective weft insertion.

6. Weaving method according to claim 5, characterized in that a predetermined amount of the respective weft thread (40, 42) is actively fed when the corresponding color control means (18, 20) selects for the introduction of a weft thread (40, 42).

7. Weaving method according to claim 5 or 6, characterized in that in the control device, by means of a PID controller, an instantaneous setpoint position for the movement of the individual heald frames (4, 6, 8, 10) is determined and a traction deviation, that is to say the difference between the instantaneous actual position and the instantaneous setpoint position of the individual heald frames (4, 6, 8, 10) of the rapier device, is set, wherein at the time, that is to say at the predefined position, the traction deviation is substantially eliminated.