Abstract: The hollow interior of an open-end spinning rotor is defined by an inner contour, which comprises a fiber sliding surface and a fiber collecting groove. The front surface of the open-end spinning rotor may have an opening width of between 19 and 23 mm, the fiber sliding surface may have a tapering of a maximum of 10°, and while the diameter of the fiber collecting groove may measure less than 30 mm.

Abstract: A combing ring for an opening roller of an open-end spinning arrangement is provided with at least two surface coatings, one applied on top of the other. Of these two coatings, the bottom one is a wear-resistant, harder PVD coating, while the upper one is a less hard, but fiber-friendly coating having a maximum thickness of 5 ?m, preferably a chemical nickel coating. The bottom PVD coating comprises in a known way so-called droplets, whereby the thickness of the top coating is at least equal to the height of the droplets.

Abstract: An exchangeable adapter is provided for reducing the size of a trash removal opening of an opening roller housing in open-end spinning arrangements. The said adapter comprises two semi-spherical supporting surfaces at a distance to one another for positioning the adapter on corresponding rounded countersurfaces. The adapter comprises further a curved fiber guiding surface corresponding to the curve of an opening roller as well as a boundary wall for reducing the size of the trash removal opening arranged directly upstream of the fiber guiding surface. The adapter is made from profiled bars and cut to the required effective width. The fiber guiding surface can be provided with a recess which is connected with the external atmosphere and which permits the entry of air into the opening roller housing.

Abstract: A rotor shaft of an open-end spinning rotor is provided with a peg-like shaft end having a reduced diameter. The shaft end has a front-end supporting surface which can be arranged to a step bearing, said supporting surface being provided with a wear-resistant insert. The reduced diameter of the peg-like shaft end is at least 0.68 times the diameter of the rotor shaft. In addition, the reduced diameter of the shaft end measures at least 0.82 times the length of the peg-like shaft end.

Abstract: A rotor shaft of an open-end spinning rotor is provided with a peg-like shaft end having a reduced diameter. The shaft end has a front-end supporting surface which can be arranged to a step bearing, said supporting surface being provided with a wear-resistant insert. The reduced diameter of the peg-like shaft end is at least 0.68 times the diameter of the rotor shaft. In addition, the reduced diameter of the shaft end measures at least 0.82 times the length of the peg-like shaft end.

Abstract: An open-end spinning rotor has its thinnest wall thickness in the area of its fiber collecting groove. The lateral wall of the open-end spinning rotor comprises an outer contour, which—in axial section—is at least partly convex-shaped.

Abstract: A combing ring for an opening roller of an open-end spinning arrangement is provided with at least two surface coatings, one applied on top of the other. Of these two coatings, the bottom one is a wear-resistant, harder PVD coating, while the upper one is a less hard, but fiber-friendly coating having a maximum thickness of 5 &mgr;m, preferably a chemical nickel coating. The bottom PVD coating comprises in a known way so-called droplets, whereby the thickness of the top coating is at least equal to the height of the droplets.

Abstract: A brake block for a brake of an open-end spinning rotor includes a take-up for releasable affixing to a brake block support. The brake block has at least two braking surfaces, whereby one braking surface in relation to the supporting surface of the open-end spinning rotor is, in comparison to the other braking surface, set back a certain distance. The result is that, during the first operational application of the brake block, only one braking surface touches the open-end spinning rotor, while the other braking surface comes into effect only after a predetermined amount of wear of the first braking surface.

Abstract: A bobbin plate is described which is provided with yarn catching slits, with whose aid a yarn reserve winding is formed on a rotating empty bobbin tube. The bobbin plate comprises a base body as well as a nipping ring which can be pressed onto the base body and which nipping ring is flexible at its front side. The base body as well as the nipping ring are each provided with yarn catching slits in such a way that the caught thread can be nipped between the base body and the nipping ring. The supporting surface, on which the bobbin tube is disposed on the nipping ring, is so designed that a relative motion between the bobbin plate and bobbin tube is prevented.

Abstract: A brake block for a brake of an open-end spinning rotor includes a take-up for releasable affixing to a brake block support. The brake block has at least two braking surfaces, whereby one braking surface in relation to the supporting surface of the open-end spinning rotor is, in comparison to the other braking surface, set back a certain distance. The result is that, during the first operational application of the brake block, only one braking surface touches the open-end spinning rotor, while the other braking surface comes into effect only after a predetermined amount of wear of the first braking surface.

Abstract: For the purpose of cleaning an open-end spinning rotor, the fiber feed is usually interrupted and the open-end spinning rotor slowed down. Subsequently, in the case of many embodiments, after a cover is removed from the vacuum chamber, cleaning elements are inserted into the exposed rotor cup. According to the present invention, it is provided that before the open-end spinning rotor is actually uncovered, namely before it comes to a standstill, the cover is moved just a short distance away from the vacuum chamber and thereafter, that the vacuum chamber is again closed over momentarily. In this way, a fiber ring present in the inside of the rotor cup can be more easily removed before the actual cleaning of the open-end spinning rotor.

Abstract: A damping device is provided for damping the oscillations of a winding bobbin in spinning, twisting or winding machines. A bobbin holder, which can be swivelled around a swivel axle affixed to the machine, supports the rotatably supported winding bobbin, which is pressed against a drive roller. Damping elements act in swivel directions of the bobbin holder, the effect of the damping elements being greater in the swivel direction of the winding bobbin when it is raised from the drive roller than in the swivel direction when the winding bobbin is pressed against the drive roller. A friction jaw is provided for damping, which, with its pressing surface is pressed by resilient forces against a friction surface in the form of a cylinder surface. The axis of the cylinder surface is the swivel axle of the bobbin holder. The resilient force which loads the pressing surface exerts a moment on the bobbin holder, which tends to lift the winding bobbin from the drive roller.