CS203219B1 - Spinning rotor shaft mounting in open-end spinning unit - Google Patents

Description

The invention relates to the bearing of a rotor shaft in an open-end spinning unit by means of bearings, one of which is a disk-shaped aerodynamic thrust bearing, one half of which is fixed to the shaft, while the other half of the disk is fixed and forms a foot bearing.

Spinning chamber bearing units are known in open-end spinning devices at spinning chamber speeds above 40,000 rpm, in which the functions of radial and axial bearings are separated. In these bearing units, the radial bearings only accommodate radial loads, while an axial bearing is additionally provided to accommodate the axial forces. In known constructions, e.g.

061 462, Pat. cl. D 01 H 7/12, the end of the spinning chamber shaft bears at its end on an annular disk which is arranged in the oil bath, is eccentrically positioned relative to the axis of the spinning chamber shaft and is rotated.

The drawback of this construction is the intensive wear on the contacting surfaces of the shaft end and the annular disk and the sealing of the oil bath very difficult. In addition, in this construction, axial attachment of the shaft is complicated with the vertical and oppositely directed arrangement of the spinning chamber.

Λ

Furthermore, open-end spinning devices are known in which bearings of air cushions are used as radial and axial bearings, for example according to GB-A-1 375 546, Pat. cl. D 02 B 16, and German Patent No. 2,412,174.

In the construction of the British patent, a plastic lining disc is mounted at the end of the shaft facing away from the spinning chamber, the bearing surface of which has spiral grooves. This disk is in a chamber whose base plate forms the second bearing surface of the aerodynamic thrust bearing. When the spinning chamber shaft is rotated, the spiral groove disk also rotates, by means of which the air is forced into the foot bearing, thereby creating an air cushion.

The drawback of this thrust bearing is that it only retains a slight axial load, since it generates only a small airflow power.

Another major drawback of this design is the impossibility of using it as a radial bearing for the shaft of the support discs, which at present have found wide application, since they are used to increase the speed of the spinning chambers strongly.

In the bearing unit for the spinning chamber of the device according to German Patent No. 2,412,174, there is arranged a shaft which at its end does not have a spinning chamber which is supported by bearings in a housing, wherein one of the bearings constituting an aerodynamic thrust bearing is disc shaped. the half is fixedly mounted on the shaft while the other half is stationary and represents a foot bearing, with at least one of the disc halves having a spiral groove on its bearing surface. This bearing can operate in an aerodynamic state, i.e. without supplying compressed air from a foreign source . If necessary, that is, if its load capacity is insufficient, it can also function as an aerodynamic bearing, i.e. with the supply of compressed air from a foreign source to the gap between the bearing surfaces.

This design of the spinning chamber bearing unit has the following drawbacks.

When operating the bearing in aerodynamic operating condition, a foreign source of compressed air is required, which complicates the design.

When the bearing is operated in an aerodynamic operating condition, an air cushion is formed in the bearing because the helical grooves push the air towards the center of the bearing as the shaft rotates, increasing the maximum pressure at its center while decreasing the pressure towards the periphery of the bearing.

In addition, the bearing surfaces inevitably come into contact when starting and stopping. As a result, high precision manufacturing operations and assembly work are required to ensure reliable bearing operation in an aerodynamic operating state. In particular, high demands are placed on maintaining the parallelism of the bearing surfaces both during production and during operation. A flat bearing surface with spiral grooves must be machined with very high precision. The small angular points of the bearing bearing surfaces result in a reduction in bearing capacity, contact between the bearing surfaces, heating and wear.

When using plastic-lined bearing discs as radial bearings of the spinning chamber and when driving the spinning chamber shaft with a flat belt, the necessary stable parallelism between the bearing surfaces of the foot journal and the foot bearing cannot be achieved. In doing so, the approach of the bearing surfaces is caused by slight radial strikes of the bearing disks, the flexibility of their plastic lining and the vibrations of the drive belt. This approach occurs mostly in the peripheral sections of the bearing surfaces where the air cushion has a minimum overpressure, which reduces the bearing capacity of the thrust bearing.

The purpose of the invention is to provide a rotor shaft bearing in an open-end spinning unit by means of bearings, one of which is an aerodynamic disk-shaped thrust bearing, one half of which is fixed to the shaft, while the other half is fixed and forms a foot bearing.

This object is achieved in accordance with the invention in that the first disk half, which is fixed to the shaft, has holes on its front face directed towards the second disk half and diverging towards one another.

When using the support rolls as a radial bearing for the spinning chamber and arranging the spinning chamber at the bottom of the spinning device, the second fixed half of the disc is between the first half of the apertured disc and between the spinning chamber.

A further development of the invention is characterized in that the first half of the disc with holes is provided between the second fixed half of the disc and the spinning chamber.

A final feature of the invention is that the first half of the disc with holes is in one piece with the spinning chamber and its holes are formed in the body of the spinning chamber.

The advantage of the solution according to the invention is that due to the inclined openings provided in the first half of the disc, mounted on the shaft, the air generates a pressure at high speeds by centrifugal forces as it exits the openings, thereby creating an air cushion between the load caused by the rotating spinning chamber. This results in a maximum overpressure of the air flow at the circumference of the bearing surfaces of the two wheel halves.

At the time of spinning chamber shaft start and stop, the thrust bearing operates with dry friction, but due to the low friction value between the half of the aperture disc and the fixed graphite-based disc half, only slight wear of the bearing bearing surfaces occurs.

As a result of the improvements according to the invention, an increase in functional reliability during start-up and operation is ensured and simple and inexpensive production of the components is ensured.

When using the support disks as a radial bearing for the spinning chamber and arranging the spinning chamber in the lower part of the spinning device, the advantage of the invention is that the spinning chamber and the gap between the chamber and the other solid half of the disk are stable. In this case, a very close position of the two wheel halves relative to the spinning chamber and a good holding of the axial force is achieved.

Likewise, a stable position of the spinning chamber in the axial direction when arranged at the top of the spinning device is ensured. In this case, the axial force is retained by the second, fixed half of the disc.

The invention will be explained in more detail below with reference to specific embodiments and the accompanying drawings.

Fig. 1 shows the principal bearing arrangement of the rotor shaft for an open-end spinning unit as viewed from the front;

The position of the spinning chamber in Fig. 3 is the same as in Fig. 2, but viewed from the side, in Fig. 3.

shows a further variant of the rotor shaft bearing arrangement of the open-end spinning unit according to the invention in the upper position of the spinning chamber and on. FIG. 5 shows another variant of the rotor shaft bearing in an open-end spinning unit according to the invention.

The rotor shaft arrangement of the open-end spinning unit comprises, for example, radial bearings 1 in the form of gas cushions (Figs. 1, 4, 5) or in the form of rolling) disks 2, 3 which are provided on axes 4, 5 (Figs. 2, 3). and on which a shaft 6 with a spinning chamber 7 is arranged and the first disk half 8, which has a bearing surface 9 and is provided with openings 10, is fixedly fixed. The axes of these openings 10 form an acute angle with the axis of rotation of the shaft 8 and diverg in the direction The second, fixed disc half 11 is coaxial with the first disc half 8 and has a bearing surface 13. The drive of the shaft 6 with the spinning and the first disc half 8 is carried out by the drive mechanism 14.

The first disk half 8 and the second, fixed disk half 11 form an aerodynamic bearing which can be arranged differently with respect to the spinning chamber and the radial bearing. It can be mounted at the end of the shaft 8 (FIG. 1j facing away from the spinning chamber 7 or between the spinning chamber 7 and the rolling disks 2, 3 (FIGS. 2, 3) or a radial bearing 1 (FIG. 4).

The first disk half 8 can be made in one piece with the spinning chamber 7 (FIG. 5) and its openings 10 are formed in the body of the chamber.

Claims (4)

1. Rotor shaft support for an open-end spinning unit by means of bearings, one of which is an aerodynamic disk-shaped thrust bearing, one half of which is mounted on the shaft, while the other half of the disk is fixed and forms a heel bearing. The disc 8j mounted on the shaft (6) has openings (10) on its face facing the second, fixed disc half (11) and diverging towards each other. Rotor shaft arrangement in an open-end spinning unit according to claim 1, characterized in that the second, fixed disc half (11) is between the first disc half (8) with the direction of the axial force P and according to the design features of the chamber direction diverging space may take place either ports 10 to chamber ¹ (Fig. 1, 2, 3) or the chambers (fig. 4, 5), but in each case the second, fixed half 11 of the disc. The rotor shaft bearing of the open-end spinning unit operates as follows. When the rotation of the shaft S with the spinning chamber 7 and the first half 8 of the disc is started by means of the drive mechanism 14, an axial force P starts on the shaft S. At the same time suction of air into the apertures 10 starts of the first half 8 of the disc. This creates an air cushion between the support surface 9 of the first disk half 8 and the support surface 13 of the second, fixed disk half 11. The formed air cushion compensates for the axial force P. Since the formation of the air cushion is possible at a certain minimum shaft speed S, before the air cushion is formed during acceleration of the shaft 6 and after disappearing during braking of the shaft 6 the bearing operates in its dry friction state. Therefore, at least one of the bearing surfaces must have sliding properties. The bearing of the spinning chamber shaft in the open-end spinning device according to the invention has a simple construction, relatively low demands on machining and assembly accuracy, its operation is simple and has high working reliability at different spinning chamber positions in the high-speed space. They can be used in the manufacture of yarns of different fibers in length and type. BACKGROUND OF THE INVENTION and between the spinning chamber (7), wherein there is a gap between the second, fixed disc half (11) and the spinning chamber (7). 3. The rotor shaft bearing of the open-end spinning unit according to claim 1, characterized in that the first disc half (8) with openings (10) is arranged between the second, fixed disc half (111) and the spinning chamber (7). 4. The rotor shaft bearing of the open-end spinning unit according to claim 1, characterized in that the first half (8) of the disc with holes (10) is integrally formed with the spinning chamber (7) and its holes (10) are formed in the spinning body. the chamber (7).