Title of Invention	SPINNING JET HOUSING FOR AN AIR JET SPINNING ARRANGEMENT.
Abstract	A spinning jet housing for an airjet spinning arrangement for producing a spun thread from a staple fibre strand comprises a flow channel which is enclosed by a tube-like walls. The walls are penetrated in turn by injector channels. The spinning jet housing, including the flow channel and the injector channels, is a one-piece component formed without cutting action.

Full Text

BACKGROUND AND SUMMARY OF THE INVENTION Spinning jet housing for an airjet spinning arrangement T he present invention relates to a spinning jet housing for an airjet spinning arrangement for producing a spun thread from a staple fibre strand, comprising a flow channel which is enclosed by a tube-like wall, which in turn is penetrated by injector channels having a closed cross section. A spinning jet housing of this type is prior art in, for example, US patent 44 80 435 or in German published patent application 37 32 708. The injector channels provided herefore have a very small cross section and must be exactly positioned so that a vortex current provided for the spinning process can be generated. In the spinning jet housing in US patent 44 80 435, the injector channels are drilled, whereby, in order to keep the bore hole as short as possible, an insert is applied to the area of the injector channels, which permits the drilling of particularly small diameters. The spinning jet housing in German published patent application 37 32 708, in contrast, is designed as a two-part component, whereby in one part-housing an injector slit is worked in, which is open on one side and subsequently completes the closed injector channel by means of using the other part-housing as a cover. In common with both varieties is that the injector channels are applied subsequently to the spinning jet housing, which naturally leads to difficulties in reproducing the exactness of the positioning. It is an object of the present invention to manufacture the injector channels of the spinning jet housing in a simple and cost-effective way and in particular to ensure exact reproducibility. This object is achieved according to the present invention in that the spinning jet housing, including the flow channel and the injector channels, is a one-piece component formed without cutting action. Spinning airjet housing of the type according to the present invention can, in principle, be manufactured using all possible types of pressure diecasting and injection moulding processes. It is however, expedient to manufacture the spinning jet housing from oxide ceramics as this is a part subject to wear. By means of correspondingly formed core inserts, the necessary hollow spaces, first and foremost the flow channel and the injector channels, can be formed in the known way at the stage of manufacture. As all the spinning jet housings are made from one and the same tool, the exactness of the dimensions and thus the reproducibility thereof is ensured for mass production, in particular in the case of the injector channels. The manufacture of the spinning jet housing as a one-piece component formed without cutting action permits a variety of designs of the injector channels for different airjet spinning arrangements. For example, injector channels can be arranged inclined in running direction of the staple fibre strand, while alternatively the injector channels can, of course, lie in a radial plane in relation to the running direction of the staple fibre strand. In the latter case it is advantageous when the mouthpieces of the injector channels are aligned towards a conical ring surface surrounding the staple fibre strand, said conical ring surface being inclined in running direction of the staple fibres strand and being formed in one piece with the spinning jet housing. This causes the compressed air currents, which generate the vortex airflow, to be deflected from the radial direction to the running direction of the staple fibre strand. Not only the necessary channels can be inserted, but also further important, functional components can be directly formed into the spinning jet housing according to the present invention. It is thus possible that the flow channel for the staple fibre strand comprises a feed channel, which is bordered eccentrically on one longitudinal side by a fibre guiding surface which is formed in one piece with the spinning jet housing. A fibre guiding surface of this type can comprise a known way a deflecting edge which acts as a twist block. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS These and further objects, features and advantages of the present invention will become more readily apparent from the following detailed description thereof when taken in conjunction with the accompanying drawings wherein. Figure 1 is a greatly enlarged depiction of an axial intersection of an airjet spinning arrangement comprising a spinning jet housing. Figure 2 is a section along the intersectional surface II-II of Figure 1 of the spinning jet housing only. Figure 3 is an intersection of a spinning jet housing similar to Figure 1 whereby the injector channels have a different design. Figure 1 shows an airjet spinning arrangement, with which a staple fibre strand 2 fed in running direction A through a feed channel 1 is imparted a twist in a vortex chamber 3, so that a spun thread 4 is formed, which is then withdrawn through a yarn withdrawal channel 5 in withdrawal direction B. The staple fibre strand 2 can come from a drafting unit or another drafting aggregate. A fluid device generates a vortex current in the vortex chamber 3 by means of blowing in compressed air through injector channels 6 which project with their mouthpieces tangentially into the vortex chamber 3. The compressed air exiting out of the mouthpieces 7 of the injector channels 6 is drawn off by an air evacuation channel 8, whereby this has a ring-shaped cross section arranged around a spindle-shaped stationary component 9 surrounding the yarn withdrawal channel 5. The feed channel 1 forms, together with the air evacuation channel 8, a flow channel which is surrounded by a tube-shaped wall 10, which is in turn penetrated by the injector channels 6. Downstream of the exit opening 11 of the feed channel 1, a twist block in the form of a deflecting edge 12 of a fibre guiding surface 13 is arranged, which is arranged to a longitudinal side of the feed channel 1 eccentrically to the yarn withdrawal channel 5. The deflecting edge 12 is located directly upstream of the entry opening 14 of the yarn withdrawal channel 5. In the airjet spinning arrangement, the fibres to be spun are held on the one hand in the staple fibre strand and in this form are fed from the exit opening 11 of the feed channel 1 essentially without any spinning twist into the yarn withdrawal channel 5. On the other hand the fibres are subject to the effect of the vortex current in the area between the feed channel 1 and the yarn withdrawal channel 5, which vortex current drives the fibres, or at least their end areas, radially away from the entry opening 14 of the yarn withdrawal channel 5. The threads 4 produced in the above described process have therefore a core with fibres without any significant twist extending essentially in thread longitudinal direction, and an outer area, in which the fibres or the fibre areas are wound around the core. Based on an idealized process for the purposes of greater clarity, the thread structure comes about in that the front ends of fibres, in particular those, whose following-on areas are still held upstream in the feed channel 1, land essentially directly in the yarn withdrawal channel 5, while, however, following-on fibre areas, in particular when they are no longer held in the entry area of the feed channel 1, are pulled out of the staple fibre strand 2 by the vortex formation, and wound around the forming thread 4. In any case, fibres are simultaneously bound in the forming thread 4, whereby they are pulled through the yarn withdrawal channel 5, and are also subject to the vortex current which accelerates the fibres centrifugally, that is, away from the entry opening 14 of the yarn withdrawal channel 5, and pulls them into the air evacuation channel 8. The fibre areas pulled out of the staple fibre strand 2 by the vortex current form a fibre vortex which runs into the entry opening 14 of the yarn withdrawal channel 5, the longer parts of said fibre vortex winding themselves spiral-like around the outside of the spindle-like component 9 and being pulled in this spiral form against the forces of the current in the air evacuation channel 8 towards the entry opening 14 of the yarn withdrawal channel 5. With the aid of Figure 2 in addition to Figure 1, the injector channels 6 are described in more detail below. According to the embodiment shown in the above mentioned Figures, there are four injector channels 6 overall per airjet spinning arrangement, each of which is provided with a mouthpiece 7, which is, as can best be seen in Figure 2, tangentially directed in the vortex chamber 3. These injector channels 6 are arranged in a spinning jet housing 15 in a way described below, said injector channels 6 having a closed cross section. The injector channels 6 extend in a plane radial to the running direction A of the staple fibre strand 2. An annular space 16 radially surrounding the spinning jet housing 15 is connected to a vacuum source in a way not shown. The compressed air gets from the annular space 16 to the individual injector channels 6 via axial recesses 17 provided in the outer contour of the spinning jet housing 15. The annular space 16 is sealed off from the outside by a wall of a housing 18. Directly downstream of the mouthpieces 7 of the injector channels 6 a conical ring surface 19 inclined in the running direction A of the staple fibre strand 2 is provided. Although the injector channels 6 lie in a radial plane, the compressed air existing out of the mouthpieces 7 is deflected by the ring surface 19 in running direction A of the staple fibre strand 2. The conical ring surface 19 surrounds the staple fibre strand 2, whereby the mouthpieces 7 are aligned tangentially towards the ring surface 19. In order to be able to manufacture the individual functional elements very exactly and repeatedly, in particular the injector channels 6 with their small cross sections, it is provided according to the present invention that the spinning jet housing 15, including the flow channel 1, 8 and the injector channels 6, is a one-piece component formed without cutting action in addition, the conical ring surface 19 and the fibre guiding surface 13 with the deflecting edge 12 are also formed in one piece. Because of the danger of wear, the spinning jet housing is made from oxide ceramics, for example, aluminium oxide. The embodiment shown in Figure 3 has a- somewhat differently designed air jet spinning arrangement, whereby those components which are identical to those in Figures 1 and 2, are provided with the same reference numbers. A repeat description can therefore be omitted. Deviating from the embodiment shown in Figures 1 and 2, injector channels 20 are provided in the embodiment according to Figure 3 which are inclined in the running direction A of the staple fibre strand 2. The mouthpieces 21 of the injector channels 20 are again directed tangentially in the vortex chamber 3. In this embodiment a spinning jet housing 22 is also provided which is a one-piece component formed without cutting action. The injector channels 20 begin again in an annular space 23, which is connected to a source for compressed air (not shown) and from which the compressed air is fed via recesses 24 to the injector channels 20. The annular space 23 is covered on the outside by a housing 25. WE CLAIM: 1. Spinning jet housing for an airjet spinning arrangement for producing a spun thread from a staple fibre strand, comprising a flow channel which is enclosed by a tube-like wall, which in turn is penetrated by injector channels having a closed cross section, characterized in that the spinning jet housing (15; 22), including the flow channel (1,8) and the injector channels (6; 20), is a one- piece component formed without cutting action. 2. Spinning jet housing as claimed in claim 1, wherein it consists of oxide ceramics. 3. Spinning jet housing as claimed in claim 1 or 2, wherein the injector channels (20) are inclined in the running direction (A) of the staple fibre strand (2). 4. Spinning jet housing as claimed in claim 1 or 2, wherein the injector channels (6) lie in a radial plane in relation to the running direction (A) of the stable fibre strand (2). 5. Spinning jet housing as claimed in claim 4, wherein the mouth- pieces (7) of the injector channels (6) are aligned towards a conical ring surface (19) surrounding the staple fibre strand (2), said conical ring surface (19) being inclined in running direction (A) of the staple fibres strand (2) and being formed in one piece with the spinning jet housing (15). 6. A spinning jet housing as claimed in any one of the claims 1 to 5, wherein the flow channel (1, 8) for the staple fibre strand (2) comprises a feed channel (1), which is bordered eccentrically on one longitudinal side by a fibre guiding surface (13), which is formed in one piece with the spinning jet housing (15;22). 7. A spinning jet housing as claimed in claim 6, wherein the fibre guiding surface (13) comprises a deflecting edge (12) which functions as a twist block. A spinning jet housing for an airjet spinning arrangement for producing a spun thread from a staple fibre strand comprises a flow channel which is enclosed by a tube-like walls. The walls are penetrated in turn by injector channels. The spinning jet housing, including the flow channel and the injector channels, is a one-piece component formed without cutting action.

Documents:

1185-kolnp-2005-granted-abstract.pdf

1185-kolnp-2005-granted-assignment.pdf

1185-kolnp-2005-granted-claims.pdf

1185-kolnp-2005-granted-correspondence.pdf

1185-kolnp-2005-granted-description (complete).pdf

1185-kolnp-2005-granted-drawings.pdf

1185-kolnp-2005-granted-examination report.pdf

1185-kolnp-2005-granted-form 1.pdf

1185-kolnp-2005-granted-form 18.pdf

1185-kolnp-2005-granted-form 2.pdf

1185-kolnp-2005-granted-form 3.pdf

1185-kolnp-2005-granted-form 5.pdf

1185-kolnp-2005-granted-letter patent.pdf

1185-kolnp-2005-granted-pa.pdf

1185-kolnp-2005-granted-reply to examination report.pdf

1185-kolnp-2005-granted-specification.pdf

1185-kolnp-2005-granted-translated copy of priority document.pdf