EP3139391B1 - Actuator for textile guide-needles - Google Patents

Description

The invention relates to an actuator arrangement for adjusting a laying needle of a textile machine or for moving another adjustment object with at least two actuators, which are arranged on opposite sides for coupling to the adjustment object and can be actuated by electrical control. Furthermore, the invention relates to a method for moving or adjusting a laying needle of a textile machine or another adjustment object, in particular using the actuator arrangement mentioned, two actuators being arranged on both sides of the adjustment object and being operatively connected to the latter by means of respective electrical control. The adjustment or movement of the laying needle or the other adjustment object within the scope of the invention includes both rotational movements such as pivoting about an axis or bending movements around an attachment point as well as linear or other translatory movements, for example sliding movements predetermined by a guide.

Textile machines in the form of warp knitting machines with jacquard control are known, in which several laying needles are divided into laying bars and, based on electrical control commands, can be shifted or adjusted individually and selectively by at least one knitting needle pitch ( EP 0 583 631 B1 ). In order to simplify the Jaquard control, it is proposed to adjust the laying needles by means of piezoelectric transducers arranged on the laying bar and assigned to each laying needle, for which purpose a control voltage is applied to the piezoelectric transducers. Since piezoelectric transducers are comparatively small components, a space-saving installation which takes into account the narrow knitting needle pitch can be achieved for the bending or positioning transducers thus realized, an adjustment path corresponding to the knitting needle pitch being achieved. Another advantage is the low power loss with which piezoelectric transducers can work.

A disadvantage of piezoelectric transducers is the low actuating force that can be applied with them (compare EP 2 053 149 A2 , Column 2, lines 46 and 47). This can lead to so-called "bounce" or rebound effects when the laying needle hits a stop, which serves to limit the laying needle adjustment stroke. In order to reduce such vibrations when the laying needle hits the stop, it is according to the above EP 0 583 631 B1 deemed expedient to provide the laying needle stop with a permanent magnet.

In order to meet the high demands placed on positioning dynamics in Jaquard devices and to avoid the disadvantages mentioned with piezoelectric transducers, in EP 2 053 149 A2 proposed to provide an electropneumatic-mechanical actuating device which is operatively connected to an actuator for moving the laying needles and guiding them. However, the constructive implementation of the electropneumatic-mechanical concept, in view of the very limited space available for the individual components of the actuator, leads to a complex design with a large number of structural components, which in turn impairs the technical reliability. Further is over GB 1436219 another electromagnetic multiple actuator for yarn guide rods disclosed.

The object underlying the invention is to create an actuator device for textile machine laying needles or other adjustment objects that is improved compared to the disadvantages in the prior art. To solve this, the actuator arrangement specified in claim 1 and the movement or adjustment method for laying needles or other adjustment objects specified in the independent claim 13 are proposed. Optional, expedient invention training result from the dependent claims. In the following, "electromagnetic transducer" always means a PCB coil, as set out in claim 1.

According to the invention, a magnetic field generator for forming a magnetic tensile force, in particular an electric pull magnet, is used on both sides of the adjustment object, in particular the textile machine laying needle, in order to provide the adjustment object or the laying needle with linear and / or rotary, in particular bending-like, lifting movements within predetermined dead centers or to make attacks. One actuator arrangement with two electromagnetic transducers is provided for each adjustment object. On the basis of the electromagnetic, The adjustment movements can be carried out as PCB coils with the necessary force and Execute dynamics. In this regard, an embodiment of the adjustment object with ferromagnetic or magnetizable material and its arrangement between the two electromagnetic actuators is functional, wherein a magnetic air gap is formed between the actuator and each of the electronically controlled and / or electrically actuated actuators, and that of the respective electromagnetic actuator generated magnetic field is oriented to exert a tensile force on the adjustment object.

By means of the actuator arrangement according to the invention as a basic unit, a module can also be realized with several laying needles lying next to one another, each of which can be adjusted by an actuator base unit according to the invention.

The available space for the individual components of the actuator arrangement is very limited or narrow, especially in connection with textile machine laying needles. This is taken into account by the formation of the invention, according to which the electromagnetic actuating converter comprises a printed circuit with a coil, in particular a non-conductive carrier material or substrate (for example a plastic circuit board) with conductor tracks, which is referred to below as "PCB coil". In this case, one or more conductor tracks, in particular copper tracks, are formed on one or more printed circuit boards, the course of which corresponds to a coil for generating a magnetic field with magnetic tensile force.

In order to achieve high tensile forces and the associated high dynamic range, the invention provides for the PCB coil to be constructed using multilayer technology. The coil extends over several levels arranged one above the other and carrying conductor tracks. The advantage achieved in this way is, above all, the feasibility of higher numbers of turns for the PCB coil, which is accompanied by a corresponding increase in the magnetic tensile force. Practical design calculations show that for a circuit board with 2 copper layers a number of turns of the PCB coil of 10 and for a circuit board with 4 copper layers one Number of turns of the PCB coil of 20 is possible. With a laying needle width of 9 mm, a number of turns of 20 or 40 and with a laying needle width of 12 mm, a number of turns of 30 or 60 is conceivable.

In order to prevent the function of an electromagnetic transducer with its magnetic stray flux from affecting an adjacent laying needle assigned to another or neighboring electromagnetic transducer in the case of a module with several adjacent laying needles, the PCB coil or the other electromagnetic one is according to an optional inventive training Actuators with an iron or otherwise ferromagnetic body for magnetic inference put into operative connection. The advantage is the targeted bundling and guidance of the magnetic field lines, which means that there is little wastage. The yoke body can be made with sheet metal, for example. According to an expedient exemplary embodiment, the PCB coil is placed in a preferably flat system and fastened there, in order to prevent repercussions on neighboring laying needles or adjacent, other adjustment objects, over their entire width or at least with one complete side on the inference body. The attachment can be done for example by gluing.

The stray magnetic flux, which could possibly impermissibly spread to adjacent adjustment objects, can be reduced even further if the PCB coil is surrounded or surrounded by the yoke body, preferably as far as possible, or is embedded in it, with the proviso that magnetic tensile forces are still present the adjustment object can be exercised to the required extent. This can be achieved in that the PCB coil not only bears on the yoke body with its long, wide or rear side, but also with its front or thick sides. The targeted conduction of magnetic field lines while avoiding leakage flux is thereby further improved, and the magnetic tensile force on the adjustment object is further increased. The latter also serves as an example of inventive training, according to which one or more printed circuit boards of the PCB coil have a recess or one Have breakthrough, which or which is filled or penetrated by material of the ferromagnetic yoke body.

To achieve higher tensile forces, an optional inventive design is also used, according to which the yoke body is designed with a groove, groove or other depression on its surface, in which a PCB coil can be inserted. For this purpose, the course of the depression can be adapted to the contour of the PCB coil, in particular overlap with the PCB coil. It is expedient if the ferromagnetic yoke body, which possibly carries a PCB coil on each of its two opposite sides in a laying bar module with a plurality of laying needles, is made thicker by or according to the thickness of a PCB board. A groove can then be embossed into the surface of the yoke body, the depth of which corresponds to or corresponds to the board thickness of the PCB coil. This further increases the ferromagnetic yoke volume and further reduces the occurrence of magnetic leakage losses.

The mechanical stabilization is used if optionally a support device made of non-ferromagnetic, non-magnetizable or at least negligibly magnetizable but heat-conducting material is used, to which the electromagnetic actuator, i.e. the PCB coil, and / or possibly the ferromagnetic yoke body is attached are. In this way, dissipation of power loss or heat can also be achieved or promoted, in particular if the components mentioned lie flat against the support device. In order to achieve negligible magnetizability and thermal conductivity, aluminum and / or zinc, for example, is suitable as the production material for the support device or its parts.

In the context of embodiments according to the invention, the structuring of the support device into a base plate, on which the electromagnetic transducers or PCB coils and / or the yoke body or bodies are placed or applied with one side, and in a module carrier strip on which the PCB Spools or electromagnetic transducer and / or the yoke body (s) are attached and / or supported with another side. In particular, this embodiment has the advantage that the textile machine laying needle can be detachably held on the above-mentioned support device, in particular its module carrier strip. Thus, the actuator arrangement according to the invention could first be delivered to the operator of the textile machine without a laying needle and installed on the textile machine; the laying needles could then only be attached to the module carrier strip by the operator, for example detachably, after the actuator arrangement has been installed.

One advantage that can be achieved with the heat-conducting base plate or module carrier strip is that the ferromagnetic yoke body can be attached, in particular, attached or attached, over a large area of its total length, preferably in a snug manner. In addition to the improved heat dissipation, mechanical stiffening is also achieved, in particular if the base plate and the module carrier strip are firmly connected to one another or are formed in one piece.

To control the energization of the electromagnetic transducer, in particular the PCB coil, and also to control its consumption of electrical power, the use of at least one electrical switching element in the coil circuit is expedient. This also creates a simple possibility for timely actuation of the converter. The switching element can be accommodated in a space-saving manner on or within the supporting device, in particular within the base plate or module carrier strip.

An optional embodiment of the procedure according to the invention consists in that the adjustment object is given a stroke or a movement or adjustment up to a stop by energizing one of the electromagnetic actuating converters with a higher current intensity; In order to hold the adjustment object firmly at the stop in the event of vibrations, an energization with a lower current strength is then sufficient. This results, among other things, from the minimally small air gap when the system stops at the stop, and the larger one at the stop Tightening forces are possible. In the context of the invention, it is expedient to alternately carry out the electrical actuation of the plurality of electromagnetic actuating converters or the generation of their magnetic tensile forces so that a defined adjustment can be carried out by one of the transducers alone, without influence by the other transducer, with the highest possible dynamics.

Further details, features, combinations of features, advantages and effects based on the invention result from the following description of a preferred embodiment of the invention and the drawings. These show in:

Figure 1 a perspective representation of a schematic diagram of a laying needle module with a plurality of laying needles arranged next to each other with respectively assigned pairs of electromagnetic transducers, and

Figure 2 a simplified sectional view along line AA in Figure 1 .

Reference list

1 -

Module carrier bar

2 -

Laying needle

3 -

Iron trailing edge

4 -

Module carrier base plate

5 -

PCB coil

6 -

Copper railway

7 -

counter

8th -

inner recess of the PCB coil

a -

distance

L -

Air gap

9 -

Stop body

10 -

Groove in the iron yoke body

According to Figure 1 are attached to a module carrier strip 1, projecting parallel to one another, several textile machine laying needles 2 with their respective ends. At their other, free ends, the laying needles 2 are provided with thread guide elements (not shown) and can be moved from one stop body to another stop body (see Figure 2 ) move when a respective electromagnetic transducer exerts a magnetically generated tensile force on them. This leads to bending movements of the laying needle 2 fixed at one end.

Ferromagnetic iron yoke strips 3, each opposite one laying needle 2, are arranged in a mutually parallel arrangement on a heat-conducting, non-ferromagnetic module carrier base plate 4 in a heat-transferring manner over their entire length and are physically or thermally conductively connected with their one end face to the module carrier strip 1, in accordance with exemplary drawing, the module support bar 1 is placed vertically on the base plate 4. Between each two iron yoke strips 3, the respective laying needle 2 is arranged so that it can be bent back and forth, running parallel to them. The combination of carrier strip 1 and base plate 4 comprising support device 1.4 together with the associated parallel laying needles 2 and iron yoke strips 3 represents a laying needle module.

To adjust the laying needles 2, such as bending elements, the iron yoke strips 3 are each provided with a PCB coil 5 on their sides facing the laying needles, so that the iron yoke bars 3 each have a PCB coil 5 on each of the inner ones. Of the latter, only the multilayered ones (to simplify the drawing) (according to the example in Figure 1 two-layered) copper conductors 6 running in turns, forming an inductor or coil, are drawn schematically. A two-layer or multi-layer circuit board forms the PCB coil 5 together with the copper tracks 6 running in turns. Switches 7 assigned to each PCB coil 5 can be used to switch the associated copper tracks 6 or turns in a currentless or current-carrying manner. In the current-carrying state, the PCB coil 5 that is just switched on goes directly to the assigned one opposite laying needle 2 aligned magnetic field, resulting in a tensile force exerted on the ferromagnetic laying needle 2 results. The latter adjusts or swivels the laying needle 2 like a bending beam firmly clamped at the end, with its free, thread-guiding end in the direction of a stop (see Figure 2 ) is adjusted. According to the laying needle module Figure 1 the individual laying needles 2 can be adjusted independently of one another since the respectively assigned PCB coils 5 can be actuated independently of one another by means of the switches 7.

In the sectional view according to Figure 2 of the PCB coils 5, only the respective two- or multi-layer boards are schematically drawn. They each have an inner recess 8 which is filled with material of the respective iron yoke strip 3 to further strengthen the magnetic field generated by the coil turns. To isolate the copper tracks from the iron yoke strips 3, masking lacquer can be applied to the respective PCB coil 5. The respective PCB coil 5 is preferably attached with its circuit board body to the adjacent iron yoke strip 3 by gluing.

According to the present sectional view of the Figure 2 the PCB coils 5 are encompassed or framed by the iron yoke strip 3 over most of their inner and / or outer circumference, in the example shown on at least three sides. It is desirable that the respective PCB coil is embedded or embedded in the iron yoke strip in such a way that only its side assigned to the laying needle 2 or the adjustment object remains free, so as not to impair the application of the magnetic tensile force on the laying needle 2. This can be achieved, for example, with a groove 10 which is formed in the iron yoke strip 3 in the surface of the side thereof facing the laying needle 2. For this purpose, it is expedient if the iron yoke strip 3 has a correspondingly greater thickness, for example by adding one or both sides to the thickness of the PCB coil 5. The magnetic stray flux and thus the effect on neighboring PCB coils and laying needles can be noticeably reduced. This effect is further promoted by the fact that a certain distance a from an outside of the PCB coil 5 is created to a closest outer edge of the iron yoke. Accordingly, the PCB coil 5 is positioned inwards in the respective iron yoke strip 3.

According to Figure 2 there is an air gap L (which can be adjusted) between the iron yoke strip 3 or the PCB coil 5 on the one hand and the laying needle 2 on the other. The air gap L is given its minimum width when the free end of the laying needle 2, which has a thread guide elements, is brought into contact with a stop body 9 by a tensile force exerted by a PCB coil 5. The latter can be arranged, for example, at a distance from the closest PCB coil 5 or iron yoke strip 3.

With the actuator arrangement according to the invention, in particular with the according to in Figure 1 and 2 The illustrated embodiment can achieve magnetic tensile forces that allow very dynamic movements with the advantage that when the laying needle 2 is in contact with the stop body 9, as a result of the then smaller, minimized air gap L, larger tightening forces are possible which secure the system despite any vibration of the laying needle module . The inductance and the ohmic resistance of the PCB coils 5 result in time constants in the microsecond range for the dynamics of the current. After the brief lifting movement of the laying needle 2 until it abuts the stop body 9, the current requirement can be reduced. This is because the magnetic tensile force is inversely proportional to the air gap, so that the current requirement for holding the laying needle 2 on the stop body 9 is reduced.

If the current is controlled accordingly, the average power requirement per actuator or actuator can be reduced. The actuators or PCB coils 5 are operated with direct current.

Claims (14)

1. An actuator arrangement for adjusting a guide-needle (2) of a textile machine or for moving any object to be adjusted, with at least two position converters which are arranged on opposite sides for coupling to the object to be adjusted, and can be actuated by electrical control,
   wherein the position converters are each designed as electromagnetic position converters and arranged to generate a magnetic field aligned in such a manner that, when electrically controlled, a magnetic tensile force can be exerted on the object to be adjusted, characterised in that the at least two electromagnetic position converters each have a printed circuit board with at least one coil designed with multilayer technology - subsequently called "PCB coil" (5),
   wherein one or more circuit paths (6) are designed on one or more printed circuit boards, the course of the paths being designed to form a coil generating the magnetic field, wherein the coil extends over several planes arranged one over the other and bearing circuit paths.
2. The actuator arrangement according to claim 1,
   wherein a PCB coil (5) with an iron or otherwise ferromagnetic return body (3) is placed in active connection for magnetic return.
3. The actuator arrangement according to claim 2,
   wherein a PCB coil (5) is covered by, surrounded by or embedded in the return body (3) providing that magnetic tensile forces can still be exerted on the object to be adjusted (2).
4. The actuator arrangement according to claim 2 or 3,
   wherein the one or more printed circuit boards of a PCB coil (5) have a recess (8) which is filled out with material of the ferromagnetic return body (3) or is penetrated by same.
5. The actuator arrangement according to one of claims 2-4,
   wherein the return body (3) has a groove (10), slot or any other type of recess, wherein a PCB coil (5) is or can be introduced.
6. The actuator arrangement according to one of the preceding claims, with a supporting apparatus (1, 4) made of non-ferromagnetic, non-magnetisable or at least only insignificantly magnetisable, but heat-conductive, material, on which a PCB coil (5) and/or optionally the return body (3) are attached.
7. The actuator arrangement according to claim 6,
   wherein the supporting apparatus (1, 4) comprises a base plate (4), on which the PCB coils (5) and/or the return body (bodies) (3) is (are) arranged on one side, and/or a module-supporting bar (4), on which the PCB coils (5) and/or the return body (bodies) (3) is (are) attached and/or held on a different side.
8. The actuator arrangement according to claim 7,
   wherein the ferromagnetic return body (3) is fixed to the heat-conductive base plate (4) and/or module-supporting bar (1) over at least the majority of its overall length.
9. The actuator arrangement according to one of the preceding claims,
   wherein a PCB coil (5) is provided with an electrical switching element (7) for current feed.
10. The actuator arrangement according to claim 9 and one of claims 8-10,
    wherein the switching element (7) of a PCB coil (5) is arranged on or inside the supporting apparatus (1, 4).
11. The actuator arrangement according to one of the preceding claims,
    wherein the guide-needle (2) or the other object to be adjusted is formed with ferromagnetic material and arranged between the at least two electromagnetic position converters which have PCB coils,
    wherein a magnetic air gap (L) is formed between the object to be adjusted (2) and each of the electrically actuated position converters (5).
12. The actuator arrangement according to claim 11 and one of claims 6-8,
    wherein the guide-needle (2) or the other object to be adjusted is designed as a flexural element and fixed with one end to the supporting apparatus (1, 4), optionally the module-supporting bar (1).
13. A method for moving a guide-needle (2) of a textile machine or any other object to be adjusted, using an actuator arrangement according to one of the preceding claims,
    wherein two position converters are arranged on both sides of the object to be adjusted and are placed in active connection with same by respective electrical control,
    wherein an electromagnetic position converter (5) is used, characterised in that the electromagnetic position converter has a printed circuit board with a coil designed with multilayer technology - hereinafter called "PCB coil" (5) - and is controlled to create a magnetic field,
    wherein one or more circuit paths (6) are designed on one or more printed circuit boards, the course of the paths being designed to form a coil generating the magnetic field,
    wherein the coil extends over several planes arranged one above the other and bearing circuit paths, and
    wherein the magnetic field is aligned to exert a tensile force on the object to be adjusted (2).
14. The method according to claim 13,
    wherein, by having an electromagnetic position converter (5) designed as PCB coil flow through it, the object to be adjusted (2) with a higher current is given a swing, and then the flow through of current is reduced to a lower current to hold the object to be adjusted (2) at a stop (9).

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