DE102004005429A1 - Faserleitkanal for an open-end spinning device and method for producing a Faserleitkanals - Google Patents

Abstract

The invention relates to a fiber guide channel for an open-end spinning device and to a method for producing such a fiber guide channel. DOLLAR A Such per se known Faserleitkanäle are used for the pneumatic transport of individual fibers, which are combed from a rotating in an opening roller housing opening roller from a master fiber tape, to a spinning rotor, which rotates at high speed in a rotor housing unterdruckbeaufschlagbaren. DOLLAR A According to the invention it is provided that the Faserleitkanal (13) is formed as a hollow body whose light cross-section towards its mouth (26) decreases towards DOLLAR A wherein the Faserleitkanal (13) is produced by a manufacturing process in which a mixture From a sinterable material and a binder by injection molding first a first excessive raw form is created, which is converted by debinding in a porous intermediate form and brought by sintering in a nachbearbeitungsarme final shape.

Description

The The invention relates to a Faserleitkanal according to the preamble of the claim 1 and a method for producing a Faserleitkanals according to the preamble of claim 4.

Faserleitkanäle are in the context of open-end spinning devices, in particular with open-end rotor spinning devices, has long been known and described in numerous patent applications.

At execution such fiber guide channels, in which a pneumatic transport of individual fibers takes place, are particularly in terms of geometric design and the surface quality high Requirements made.

The is called, the flow conditions within such Faserleitkanals must ensure that the fibers while the transport remain largely stretched or stretched become.

In addition, must the surface of these components throughout be smooth so that during the pneumatic transport of the fibers does not constitute fibers can. In particular, it should be avoided that in the boundary layer region of Fiber guide harmful Air vortex can form.

Regarding the Production of such fiber guide channels have also been known for a long time various manufacturing methods.

In the DE-AS 23 64 261 , of the DE-OS 28 00 795 or the DE 195 11 084 A1 Fiber guide channels are described, for example, which are wholly or partially made of sheet steel parts.

According to DE 28 00 795 A1 For example, it is provided that in a first step of a steel sheet initially a Faserleitkanaleinrichtung is made.

This prefabricated component is then placed in a die-casting tool with, for example, liquid Cast aluminum.

This Manufacturing process, however, has no entry into practice found because the problems encountered are not satisfactory too were solved.

It For example, it had turned out to be made of sheet steel prefabricated Faserleitkanaleinrichtung in die casting deformed due to the high pressure and therefore be supported consuming got to.

There is also in this manufacturing process constantly the risk that liquid casting material penetrates into the fiber channel, which has a very negative effect on its surface quality.

The Faserleitkanaleinrichtung according to DE 195 11 084 A1 is also designed as a cold-formed sheet steel part. In this device, however, the sheet steel part is interchangeable in a corresponding receiving bore of a prefabricated opening roller housing fixed and sealed relative to the opening roller housing by a voltage applied to the outer circumference of the Faserleitkanaleinrichtung O-ring seal.

Opposite the Duct plate is this known Faserleitkanaleinrichtung means a special hose nozzle sealed.

In However, in practice, it has been found that in such steel sheet constructions Sealing problems can occur the proper spinning operation do not allow.

Furthermore, for example in the DE 197 12 881 A1 , Faserleitkanäle described, which are designed as Druckgußteile.

These known Faserleitkanäle have a foot part with a centering device and an annular groove for receiving a Sealing ring on and can about this footboard fixed in an accurate and airtight manner in a corresponding bore of the opening roller housing become.

Of the Fiber guide opens in the area of a central channel plate adapter receptacle in a bore, being this area over a corresponding seal is also hermetically sealed.

The Faserleitkanäle according to DE 197 12 881 A1 are also provided with wear protection, for example by immersion in a nickel dispersion bath.

The prescribed fiber guide channels have proven themselves in practice in principle and are in large numbers in open-end rotor spinning devices in use.

Indeed is the production of such Faserleitkanäle as zinc or aluminum die-casting quite expensive and leads to permanent high tooling costs.

Besides that is in this manufacturing method the reject rate, in particular due to the high quality requirements to the surface quality of the fiber guide channels, relative high.

outgoing From the aforementioned prior art, the invention is the task underlying, a Faserleitkanal and a method for manufacturing of fiber guide channels to develop a cost-effective, this means, preferably low-reject production of fiber guide channels allows wherein also in terms of the shape of the fiber guide channels no to be set to tight limits.

These The object is achieved by a Fiber guide channel solved, as described in claim 1.

One preferred method for producing such a Faserleitkanals is described in claim 4.

advantageous Embodiments of the method according to the invention are the subject the claims 5-9.

The have Faserleitkanäle inventive In particular, the advantage that they are in terms of their outdoor and Internal shape of procedural restrictions as far as possible are free. This means, the fiber guide channels are in terms of their shape also in the field of their light Cross section hardly restrictions subjected and can in a simple way with a flow-optimized Channel profile are provided.

There In addition, the reject rate is extremely low in the proposed manufacturing process is, is also a cost effective Production of such Faserleitkanäle possible.

The After sintering resulting end body can almost without further After-treatment in subsequent finishing processes almost all conceivable heat treatment and surface treatment methods be subjected.

The is called, in that fiber guides, which are manufactured according to the above-described manufacturing method, a big part the usual, Relatively expensive rework is eliminated and the reject rate is very low the Faserleitkanäle invention process stage and thus cost-effective as well as with high quality be made.

One corresponding method is also called MIM or PIM technology (Metal Injection Molding = MIM or (Powder Injection Molding = PIM).

to Production of fiber guide channels according to the MIM or PIM technology will be first an organic binder with a sinterable substance, for example a very fine (<20 μm), mostly spherical Metal powder or an oxide ceramic powder to a homogeneous Mass mixed or processed into so-called pellets.

Of the Volume fraction of the metal powder or the oxide-ceramic powder in this homogeneous mass usually over 50%.

The the mass obtained is subsequently handled analogously to plastic processing on injection molding machines. The is called, by means of an injection molding machine become raw bodies from this mass which already has all the typical geometric features of the have manufacturing Faserleitkanals, but still one to the binder content increased volume have.

Then be in a so-called debinding process the organic binder from the green bodies away.

The remaining porous intermediate body are then sintered under different inert gases or vacuum to fiber guide channels with the final dimensions compacted.

The Occurring shrinkage can reach final densities greater than 96% to lead.

Basically exists when using the MIM or PIM technology also the possibility For example, by targeted mass concentration, the inner contour or to influence the clear width of Faserleitkanäle.

The is called, through reinforced, external mass attachment in certain areas of the Faserleitkanals the shrinkage behavior of the raw body controlled and thus, for example, the resulting in the production of the green body drafts counteracted.

By the material of the sinterable material e.g. Metal powder or oxide-ceramic Powder, the grain size of the sinterable Material as well as the selection of debinding and / or sintering parameters can be targeted Influence on the surface structure of the Faserleitkanals be taken. That is, for further processing or heat treatment best surface structure can already be determined in advance.

at the application of the above-described method is of course the Possibility, the fiber guide channels either one-piece or multi-part form.

In a multi-part design, it is advantageous if at least one insert arranged in the region of the inlet opening of the fiber guide channel piece, which forms the Faserabrißkante and is thus exposed to a high load, according to the MIM or PIM technology is produced, since an insert thus produced is already very wear-resistant and can be easily further improved by appropriate post-treatments.

The is called, with fiber guide channels that according to the MIM or PIM technology are produced, the so-called egg shell effect (= hard Shell but soft core) avoided. Show the created components continuously a high wear resistance on.

The in contact with the fibers coming surfaces can additionally improved in a relatively simple manner, for example by chromium plating become.

Also with one-piece fiber guide channels in particular, the surface quality of the fiber guide channel by chromium plating or the like. Optimized in a relatively simple manner become.

The is called, by a suitable coating can be a very smooth surface of the Fiber guide channels are created, which is very positive on the flow conditions within the Faserleitkanals and thus in total on the spin result of entire facility.

The manufactured according to the invention fiber guide channels or the inserts can advantageously also another known heat treatment, For example, nitriding, boriding, etc., be subjected.

Such heat-treated Components are also characterized by a long service life.

The Invention is described below with reference to an illustrated in the drawings embodiment explained in more detail.

It shows:

1 schematically in side view an open-end rotor spinning device with a switched between opening cylinder housing and spinning rotor, the invention Faserleitkanal,

2 1 is a front view of an opening roller housing with a first embodiment of a one-piece fiber guide channel manufactured according to the MIM or PIM technology,

3 the in 2 represented Faserleitkanal in side view,

4 a second embodiment of a one-piece Faserleitkanals made according to the MIM or the PIM technology,

5 a multi-part Faserleitkanal with a manufactured according to the MIM or PIM technology insert.

In the 1 illustrated open-end rotor spinning device 1 has, as is known, a rotor housing 2 in which a spinning rotor 3 revolves at high speed.

The spinning rotor 3 is with his rotor shaft 4 in the gusset of a support disk bearing 5 supported by a machine-length tangential belt 6 that by a pressure roller 7 employed, charged.

The rotor housing, which in itself is open towards the front 2 is during operation by a pivotally mounted lid member 8th that a channel plate 37 with a seal 9 has, closed and via a corresponding pneumatic line 10 to a vacuum source 11 connected in the rotor housing 2 necessary spin negative pressure generated.

In a receiving opening, not shown, of the channel plate 37 is a preferably replaceable channel plate extension, a so-called channel plate adapter 12 arranged, the one thread withdrawal nozzle and the mouth region of a Faserleitkanals 13 having.

On the cover element 8th that is about a pivot axis 16 is limited rotatably mounted, is an opening roller housing 17 established. The cover element 8th also has rear bearing brackets 19 . 20 for storage of an opening roller 21 or a sliver draw-in cylinder 22 on. The opening roller 21 is in the range of their whorl 23 by a circumferential, machine-long tangential belt 24 driven while driving the sliver feed cylinder 22 preferably via a (not shown) worm gear arrangement, which is based on a machine-length drive shaft 25 is switched.

The 2 shows the opening roller housing 17 in front view, partly in section.

In a connection hole 31 of the opening roller housing 17 is a one-piece fiber guide channel 13 positioned according to MIM or PIM technology.

As shown, has the connection hole 31 a stop step 32 on which the Faserleitkanal 13 supported in the installed state.

The connection hole 31 furthermore has a lateral recess 33 , in the one on Faserleitkanal 13 arranged Lagefixiereinrichtung 34 intervenes.

The fiber guide channel 13 is opposite the connection hole 31 of the opening roller housing 17 through an O-ring seal 35 sealed in a corresponding groove 36 is positioned in the Faserleitkanalfuß 44 is arranged.

The sealing of the fiber guide channel 13 opposite the channel plate 37 takes place for example via a hose nozzle 38 , attached to a contact shoulder 41 at the fiber guide channel 13 supported.

In 3 is the in 2 shown in front view, manufactured according to the MIM or PIM technology Faserleitkanal 13 shown in side view.

The fiber guide channel 13 preferably, as already mentioned above, seen in plan view, in cross-section circular foot 44 , a partially conical middle section 45 as well as a cylindrical mouth area 46 on.

In the foot part 44 is a groove 36 for receiving an O-ring seal 35 arranged. In addition, the foot part 44 one to the opening roller 21 adapted concave rounding 47 on.

The rounding 47 extends from a Faserabrisskante 50 in the direction of rotation of the opening roller 21 , The fiber guide channel 13 points in the area of the fiber tear-off edge 50 that is, in its entry area 18 a clear channel cross-section with a width / height ratio of about 3: 1 and runs, based on its width B, at its mouth 26 towards, preferably at an angle α, conical to.

How out 2 it can be seen, on the other hand, the height H of the Faserleitkanals remains 13 from its entry area 18 to its mouth 26 essentially constant.

The 4 shows a further embodiment of a one-piece Faserleitkanals 13 ,

As indicated, the fiber guide channel 13 in the area of its entrance opening 18 a bottleneck 15 on, the clear cross section of the fiber guide channel 13 in terms of height H limits.

With such an embodiment a Faserleitkanals leaves the flow velocity the transport air flow in the area of the entrance opening increase.

Such an increase in the flow velocity of the transport air flow in the region of the inlet opening can also be achieved by the use of an in 5 shown multi-part Faserleitkanals 13 achieve.

In such an embodiment is in the region of the inlet opening 18 of the fiber guide channel 13 replaceable one insert 27 arranged.

At least the insert 27 is manufactured according to MIM or PIM technology.

The exchangeable insert 27 that is the clear cross section of the fiber guide channel 13 significantly reduced in this area, relies on the stop level when installed 32 the receiving bore 31 of the opening roller housing 17 from.

Through the insert 27 it comes, as indicated above, to a reduction of the inlet opening 18 of the fiber guide channel 13 and thus to an acceleration in the Faserleitkanal 13 entering, due to the negative pressure in the rotor housing effective transport air flow.

In a further embodiment (not shown), the insert piece 27 Of course, be designed so that the clear cross section of the fiber guide channel 13 not narrowed.

Even with such a multi-part fiber guide channel 13 is at least the insert 27 manufactured according to MIM or PIM technology.

Claims (9)

Faserleitkanal for an open-end spinning device for the pneumatic transport of individual fibers, which are combed from a rotating in an opening roller housing opening roller from a master fiber ribbon, to a spinning rotor, which rotates at high speed in a rotor housing unterdruckbeaufschlagbaren, characterized in that the Faserleitkanal ( 13 ) is formed as a hollow body whose light cross section in the direction of its mouth ( 26 ) decreases, wherein the Faserleitkanal ( 13 ) is produced by a manufacturing method in which a mixture of a sinterable substance and a binder by injection molding first a first oversize raw form is created, which is converted by debinding in a porous intermediate form and brought by sintering in a post-processing end shape. Fiber guide channel according to claim 1, characterized that a metal powder is used as the sinterable substance. Fiber guide channel according to claim 1, characterized in that an oxygen-ceramic powder is used as the sinterable substance which is processed into pellets with the binder. A process for producing a fiber guide channel for an open-end spinning device, for the pneumatic transport of individual fibers, which are combed from a feed roller rotating in an opening roller housing from a master fiber tape, to a spinning rotor, which rotates at high speed in a rotor housing unterdruckbeaufschlagbaren, characterized in that the Fiber guide channel ( 13 ) is produced by means of the following process steps, producing a mixture of a sinterable substance and a binder, producing a green body from this mixture by powder injection molding, freeing the green body of its binder constituents and solidifying the porous green body by sintering to its final shape. Method according to claim 4, characterized in that that the inner contour of the Faserleitkanals by targeted mass concentration on the outer circumference can be influenced. Method according to claim 4, characterized in that that the surface texture the Faserleitkanals by the material of the sinterable material, the Grain size of the material and the debindering and sintering parameters are influenced can. A method according to claim 4, characterized in that at least one in the region of an inlet opening ( 18 ) of the fiber guide channel arranged insert ( 27 ) is manufactured according to the above method steps. Method according to claim 4, characterized in that the fiber guide channel ( 13 ) can be subjected to a heat treatment (for example, nitriding, boriding, etc.). Method according to one of the preceding claims, characterized in that the coming into contact with the individual fibers surface of the fiber guide channel ( 13 ) is coated.