Open-end spinning machine having a plurality of spinning units and a movable servicing apparatus

An open-end spinning machine is provided having a servicing apparatus that can be moved along a series of spinning units, each unit containing one spinning rotor assembly comprising a shaft and a rotor. It is provided that in the individual spinning units, the shafts of the spinning rotor assemblies are disposed in wedge-shaped gaps formed by pairs of supporting disks and the shafts are driven by a tangential belt. The servicing apparatus contains a brake that can be applied to the rotor when servicing of a unit is required. The rotor is stopped while, at the same time, the drive of the tangential belt is interrupted via a bracket pulley that can be moved away from its operating position. In addition, members are provided for securing the spinning rotor in its operating position during the braking.

BACKGROUND AND SUMMARY OF THE INVENTION 
This invention relates to an open-end spinning machine having a plurality 
of spinning units that are arranged next to one another and each 
containing a spinning rotor connected to a shaft. The shaft is radially 
disposed in a wedge-shaped gap formed by a pair of supporting disks and is 
driven by means of a tangential belt. The belt is biased in the direction 
of the shaft by means of a pressure pulley arranged on a movable arm that 
is biased by a spring. The machine has at least one movable servicing 
apparatus that can be applied to each spinning unit. The servicing 
apparatus contains means for exposing the spinning rotor and means for 
moving the arm with the pressure pulley into an inoperative position. 
An open-end spinning machine of the general type is disclosed in German 
DE-PS No. 23 60 296. The shafts of the spinning rotors of the spinning 
units are disposed in normal radial bearings. For stopping the spinning 
rotor, the movable servicing apparatus operates a lever bar system via 
which the arm with with the pressure pulley is moved to an inoperative 
position. At the same time, a brake present in each spinning unit is 
applied to the rotor shaft. In the case of open-end spinning machines used 
in practice, the rotor shafts, deviating from the construction disclosed 
in DE-PS No. 23 60 296, are disposed in wedge-shaped gaps formed by 
supporting disks. In these open-end spinning machines, the brake of the 
individual spinning units is designed in such a way that it is applied to 
the rotor shaft from the same side as the tangential belt when the 
tangential belt is lifted off for the purpose of interrupting the drive. 
The brake will then take over the securing of the rotor shaft and thus of 
the whole spinning rotor in its operating position. The brake is applied 
to the shaft of the spinning rotor next to the tangential belt. Because of 
the relatively small diameter of the shafts of the spinning rotors, 
relatively high braking forces must be applied in order to achieve 
effective braking. These relatively high braking forces result in 
increased wear of the brake linings. In addition, the diameter of the 
shaft cannot be decreased which would be desirable in the case of 
transition to significantly higher speeds. The brake that is applied to 
the shaft in the axial direction of the shaft also requires a certain 
space, such that the length of the shaft cannot be decreased at all or 
cannot be decreased significantly which would be desirable for very high 
speeds. 
An objective of the present invention is the provision of an open-end 
spinning machine wherein constructive limitations in the area of the 
bearings of the spinning rotors are decreased. This objective is achieved 
by providing the servicing apparatus with a brake that can be applied to 
the rotor and by providing means that secure the spinning rotor in the 
operating position when the pressure pulley is moved away. 
Since the braking of the spinning rotor no longer takes place at the rotor 
shaft, the space requirements are decreased. Accordingly, the supporting 
disks can be moved closer together while the rotor shaft, at the same 
time, can be designed to be shorter. Since relatively high braking forces 
no longer affect the shaft, it may have a smaller diameter without the 
danger of unacceptable heating and/or deformation. The braking at the 
rotor has the advantage that the application of the brake takes place at a 
relatively large circumference so that the necessary braking force can be 
lowered. In addition, the brake that is susceptible to wear is part of the 
servicing apparatus. In the construction, checking or regular maintenance 
can be carried out much more easily. Means need only be provided for 
securing the operating position of the spinning rotor which in most cases 
are not subjected to significant wear. 
In an advantageous development of the present invention, the means for 
securing the spinning rotor in its operating position are part of the 
servicing apparatus which can be applied to the exposed rotor. These means 
therefore do not have to be provided for each spinning unit but only for 
the servicing apparatus. In this development, it is especially easy from a 
constructive point of view, when the means for the securing of the 
spinning rotor in its operating position and the brake are designed as a 
structural component that can be applied to the rotor jointly. 
In another advantageous development of the invention, it is provided that 
the brake contains tong-type grippers which can be applied to the rotor in 
the radial direction by means of brake shoes. These tong-type grippers may 
take over the securing of the spinning rotor in its operating position. It 
is advantageous that the brake shoes have profiling and reach around the 
profiling of the rotor from the outside. This results in axial as well as 
in radial securing. 
In a further development of the invention, the brake can be applied in an 
axial direction toward the rotor and the shaft of the spinning rotor is 
supported by a stop in the axial direction. In this embodiment, the 
spinning rotor is clamped between the brake and the axial stop so that it 
is secured in its position. In this case, it is advantageous when the 
brake, by means of a conically expanding brake lining, in the axial 
direction, can be applied to the exterior side of the rotor having at 
least approximately the same conical contour. 
In a further development of the invention, the brake is provided with 
centering elements which in the case of the axial application to the rotor 
of a spinning unit, engage in counterparts, which are arranged at the 
spinning unit in a position that is aligned precisely with the rotor 
plate. By means of this measure, in the case of an application of the 
brake, an alignment with respect to the rotor is achieved so that this 
rotor is gripped precisely in its operating position and can be held 
there. 
In a further development of the invention, each spinning unit is equipped 
with means for fixing the operating position. These means are applied to 
the shaft of the spinning rotor. In this case, the brake of the servicing 
apparatus generally must contribute nothing to securing of the spinning 
rotor in its operating position, even if this is possible as a support. in 
the case of a simple embodiment of the invention, it is provided that each 
spinning unit is equipped with at least one stationary stop which is 
located at a small distance opposite the shaft on the side that faces away 
from the wedge-shaped gap. In the case of another embodiment of the 
invention, it is provided that each spinning unit is equipped with a 
supporting disk that can be applied to the shaft by the servicing 
apparatus. This disk then takes over the load by means of which the shaft 
of the spinning rotor is pressed into the wedge-shaped gap when the 
pressure pulley and the tangential belt for the interruption of the drive 
are moved away from the shaft of the spinning rotor. 
In order to keep the cost as low as possible in this case, it is 
advantageous when the supporting disk be mounted on holding elements 
carrying the pressure pulley in such a way that when the means for moving 
away of the pressure pulley are operated, the supporting disk can be 
applied to the shaft. 
Other objects, advantages and novel features of the present invention will 
become apparent from the following detailed description of the invention 
when considered in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE DRAWINGS 
Referring now to FIGS. 1 to 3, the spinning rotor 1 exhibits a rotor 2 and 
a shaft 3. 
The rotor 2 is pressed onto the shaft 3 by means of a ring collar and has a 
hollow interior that is open on the side facing away from the shaft 3. The 
shape of the inside space corresponds approximately to the outside contour 
of the rotor plate. On the open side, a sliding wall starts for the fed 
fibers which subsequently changes into a fiber collecting groove which is 
located in the area of the largest diameter of the rotor 2. 
The shaft 3 of the spinning rotor assembly 1 is disposed radially in 
wedge-shaped gaps 10 formed by two pairs 4 and 5 of supporting disks. The 
pairs 4 and 5 of supporting disks each consist of two supporting disks 6, 
7 and 8 and 9 which each have a metallic disk-shaped basic form 17 which, 
at its circumference, is equipped with a fitting 18 consisting of a 
plastic ring. The circumference of the ring forms the bearing surface for 
the shaft 3. The supporting disks 6, 8 and 7, 9 which are located on 
separate sides of the shaft 3 are arranged on joint shafts 19 and 20 
which, by means of roller bearings, are disposed in bearing housings 21 
and 22. The bearing housings 21 and 22 are arranged in arcuate receiving 
means of a joint bearing block 23 in which they are secured by holding 
means 24 designed as spring clips. The shafts 19 and 20, as shown in a top 
view in FIG. 3, are located in planes that are parallel to one another. In 
transverse direction to this plane, i.e., in the longitudinal direction of 
a tangential belt 11 driving the shaft 3, these shafts are angularly 
separated by an angle of about 1.degree., relative to axis 29 extending 
approximately in the center between the pairs 4 and 5 of supporting disks. 
The setting angle is built into the arcuate receiving means of the bearing 
block 23 so that the shafts 19 and 20, when their bearing housings 21 and 
22 are placed in the bearing block 23, are aligned correspondingly. 
The tangential belt 11 extending approximately in the center between the 
pairs 4 and 5 of supporting disks, moves along directly against the shaft 
3 and secures it in the wedge-shaped gap 10 of the pairs 4 and 5 of 
supporting disks. The tangential belt 11 is biased with a pressure pulley 
12 which biases the tangential belt 11 in the direction of the shaft 3 and 
deflects it slightly with respect to the shaft. The returning end 13 of 
the tangential belt 11 is returned on top on the pressure pulley 12. Axle 
30 of the pressure pulley 12 is disposed rotatably on an arm 14 that can 
be swivelled around a stationary axis 15. The arm 14 is loaded with a 
loading spring 16 in the direction of the tangential belt 11 and the rotor 
shaft 3. 
By means of the setting of the shafts 19 and 20 in connection with the 
moving direction A of the tangential belt 11 as well as in connection with 
the resulting rotating directions C and D of the pairs 4 and 5 of 
supporting disks, the supporting disks 6, 7, 8 and 9, subject the shaft 3 
of the spinning rotor assembly 1 to an axial force away from the rotor 2 
in the direction of the Arrow B. The shaft 3, in the axial direction, is 
supported against this axial force by a step bearing ball 27 which itself, 
is supported by a bolt 28 that is essentially resilient in the radial 
direction with respect to the shaft 3. 
In the case of the embodiment according to FIGS. 1 to 3, the rotor shaft 3 
has a decreased diameter in the area between the two pairs 4 and 5 of 
supporting disks, while the areas that contact the pairs 4 and 5 of 
supporting disks are designed as enlarged ring collars 25 and 26 which 
move on the fittings 18 of the pairs 4 and 5 of supporting disks. The ring 
collar 25 is extended up to the rotor 2 so that the rotor 2, with its ring 
collar, is pressed onto the ring collar 25. In order to protect the rotor 
shaft 3 from wear, it is provided with a coating consisting of silicon 
carbide or containing silicon carbide particles placed in a metallic 
matrix. It would actually be sufficient to coat only the area of the ring 
collars 25 and 26 but the application of the layer is simpler when the 
rotor shaft 3 as a whole is coated. 
In order to disengage the drive of the shaft 3 of the spinning rotor 
assembly 1, the arm 14 with the pressure roller 12 arranged laterally next 
to the shaft 3 is lifted against the spring 16. The tangential belt 11, by 
means of guide pulleys (not shown) is guided in such a way that, when the 
pressure pulley 12 is moved away, it disengages itself from the shaft 3 of 
the spinning rotor assembly 1. The arm 14 is provided with an extension 31 
at which an adjusting lever 33 is applied via a joint 32. The adjusting 
lever 33, via another joint 34, is connected with an operating lever 35 
that is pivotable around a stationary shaft 36 of holding means 37. The 
operating lever 35 protrudes from the operating side of the spinning unit 
with one arm 38. A thrust piece 39 forms the end of the arm 38. An 
operating member 40 of a movable servicing apparatus is applied to the 
thrust piece 39. For the purpose of being swivelled in the direction of 
the Arrow F, member 40 is connected to a drive that is not shown. The 
movable servicing apparatus (see also FIGS. 11 and 12) can be moved along 
the open-end spinning machine and can be selectively applied to the 
individual spinning units. 
The movable servicing apparatus also has a brake 41 which can be applied to 
the rotor 2 in the axial direction. The brake 41 has a brake lining 41' 
that is adapted to the conical outside contour of the rotor 2. This brake 
lining 41' is mounted on a bell-shaped component 42, which in the 
direction of the Arrow E can be applied axially to the rotor 2 by the 
servicing apparatus. The bell-shaped component 42 is extended via pipe 43 
through which a cleaning device that is not shown can be applied to the 
rotor 2. If required, the bell-shaped component 42 can be connected to a 
vacuum source via the pipe 43, for the removal of the detached dirt 
particles. The rotor brake 41, by means of the brake lining 41' clamping 
onto the rotor 2 on the outside, presses the spinning rotor assembly 1 
with its shaft 3 against the step bearing ball 27. This step bearing ball 
27, during the braking, is clamped between the brake lining 41' and the 
step bearing ball 27. Accordingly, it is secured axially in the operating 
position even when the tangential belt 11 and the pressure pulley 12 are 
lifted off. 
In the following developments of the present invention, the same reference 
numbers are used as were used in the embodiment according to FIGS. 1 to 3 
to the extent that these refer to components which at least in their 
function correspond to components that have been described. 
In the case of the development according to FIG. 4 and 5, the spinning 
rotor assembly 1 and its bearing as well as its drive are shown in 
operating condition in FIG. 4. In FIG. 5, the drive of the spinning rotor 
assembly 1 is interrupted. The shaft 3 of the spinning rotor assembly 1 
disposed in the pairs 4 and 5 of supporting disks is driven by a 
tangential belt 11 which, by means of a pressure pulley 12 slightly 
deflecting the tangential belt 11 next to the shaft, is pressed against 
the shaft 3. The pressure pulley 12 by means of shaft 30 is disposed on 
arm 14 that can be swivelled around a stationary axle 15 and is biased by 
a spring 16 in the direction of the tangential belt 11. At the shaft 30, 
another arm 46 is linked that has a pressure disk 45 that can be rotated 
around a shaft 47. This pressure disk 45 is applied to the shaft 3 of the 
spinning rotor assembly 1 in such a way that it holds the shaft 3 in the 
wedge-shaped gap 10 between the pairs 4 and 5 of supporting disks when the 
pressure pulley 12 and the tangential belt 11 are lifted off. A tension 
spring 48 is arranged between the arm 14 and the arm 46. A connecting rod 
49 is applied to the free end of the arm 46. The connecting rod 49 in the 
direction of the arrow G, i.e., in the direction toward the tangential 
belt 11 and the shaft 3, is operable in a manner that is not shown in 
detail by the movable servicing apparatus. During the operation, the 
pressure disk 45 is applied to the shaft 3. In the case of a further 
movement of arm 46, via the connecting rod 49, the contact point of 
pressure disk 45 on the shaft 3 forms an axis of rotation around which the 
arms 14 and 46 can then be swivelled jointly moving the pressure pulley 
12, against the effect of the spring 16, away from the tangential belt 11. 
When the connecting rod 49 is released again, the pressure disk 45, 
because of the effect of the tension spring 48, moves away from the shaft 
3 while at the same time, the pressure pulley 12, because of the effect of 
the spring 16, is again applied to the tangential belt 11. 
The pressure disk 45 of the development according to FIG. 4 and 5 causes a 
clear securing of the position of the shaft 3 of the spinning rotor 1, so 
that the spinning rotor 1, also after the interruption of the drive, is 
held in an exactly defined position. It is then possible, as shown in FIG. 
4, to apply a brake 41 to the rotor 2 on one side without the spinning 
rotor having to carry out a tilting movement by means of which it may, for 
example, run against an opening of the housing 44. The brake 41 is part of 
a movable servicing apparatus which is applied to the corresponding 
spinning unit. It has a guiding part 52 that can be applied to the 
spinning rotor assembly 1 in the axial direction corresponding to the 
Arrow E. It also has a lever arm 50 mounted at the guide part 52 and able 
to be swivelled around an arbor 51. The lever arm 50 carries a brake 
lining 41' that engages with the outside of the rotor 2. 
In the development according to FIG. 6, the operating position of the shaft 
3 is secured by a stationary stop 58 designed as a guiding sleeve which 
surrounds the shaft 3 with a small amount of radial play. The guiding 
sleeve 58 which advantageously has a slideway lining for the shaft 3 is 
part of a housing in which the step bearing ball 27 and the bolt 28 are 
housed. 
The brake 41 of the development according to FIG. 6 has grippers 53 and 54 
that can be swivelled around a shaft 55 in a tong-type manner. The 
grippers 53 and 54, at their ends, carry brake linings 41' which clamp the 
rotor 2 between them. The brake linings 41' have a conically sloped 
interior surface 61 that is adapted to the outside contour of the rotor 2. 
The tong-type grippers 53 and 54 are arranged within a tube-shaped guiding 
part 57 and are supported against its inside wall by means of elastic 
rings 56. When the brake linings 41' are applied to the rotor 2, they can 
adjust themselves to a certain extent with respect to the rotor 2. The 
applying motion taking place axially with respect to the spinning rotor 
assembly 1 during which the brake linings 41' come to rest against the 
rotor 2, is sufficient for the braking. In addition, the tong-type 
grippers 53 and 54 are tightened by additional elements by means of a 
guide ring which within the tube-shaped guide part 47 can be applied to 
the outside areas of the tong-type grippers 53 and 54. 
In deviation from the development according to FIG. 6, it is provided in 
another development that the brake linings 41' have a profiling that is 
adapted to the outside contour of the rotor 2 and during the application 
reach around the rotor 2 in the area of its largest diameter from the 
outside and engage the rotor 2 there. In this case, the tong-type grippers 
are sufficient for fixing the rotor 2 and thus also the shaft 3 of the 
spinning rotor assembly in its operating position during braking when the 
drive is disengaged. 
In the development of FIG. 6, it is also provided that the brake 41, when 
it is applied to the rotor 2, is centered precisely with respect to the 
rotor 2. For this purpose, a centering bolt 59, via a holding means, is 
mounted at the guide part 57. The centering bolt 59, when guide part 57 is 
applied axially to the spinning rotor assembly 1, moves into a centering 
piece 60 having a funnel-shaped entrance opening 60'. The centering piece 
60 is arranged in a stationary manner at the spinning unit at a distance 
from the rotor 2 that is exactly defined. Advantageously, at least two 
such centering devices are provided which cause a centering of the guide 
part 57 and thus of the brake 41 in two planes extending at a right angle 
to one another. 
In practice, it is useful to provide more than two tong-type grippers 53 
and 54. Preferably, corresponding to FIG. 7, three such grippers having 
brake linings 41' are used at uniform angular distances of 120.degree. 
each. 
In the case of the development according to FIG. 8, a brake 41 provided 
with brake linings 41' is applied axially to the rotor 2 of a spinning 
rotor assembly 1 of a spinning unit. The said brake linings 41' having a 
brake surface 61 that is complementary to the outside contour of the rotor 
2. The holding means 62 which each carry a segment of a brake lining 41' 
are subdivided by axial slots 63 so that they are elastically flexible in 
the radial direction to the rotor 2. It is advantageous to provide more 
than two segments for the brake linings 41' and more than two holding 
means 62, especially three holding means 62 corresponding to the 
embodiment according to FIG. 7 that are arranged at an angular distance of 
120.degree.. 
In the case of the development according to FIG. 9 and 10, a pressure 
pulley 12 is combined with two pressure disks 68 and 69 that can be 
applied to the shaft 3 of a spinning rotor assembly 1. The pressure pulley 
12 with one shaft 47 is disposed on an arm 46. One end of arm 46, via a 
shaft 30, is linked to an arm 14 that can be swivelled around a stationary 
shaft 15. The arm 14 is biased with a leaf spring 16, one end of which is 
fastened via a holding means 64 in a stationary manner, and the other end 
of which rests against a thrust piece 65 of the arm 14. The end of the arm 
46 that is returned to the area of the stationary arbor 15 is linked to a 
tension rod 49. In the direction of the Arrow G, i.e., in the direction of 
the tangential belt 11, the rod 49 can be moved by a movable servicing 
apparatus in a manner that is not shown in detail. The pressure pulley 12 
has a smaller diameter than the two pressure disks 68 and 69 arranged 
laterally to it. In an area next to the shaft, pulley 12 rests against the 
tangential belt 11 in the operating condition, the pressure disks 68 and 
69 being at a short distance to the shaft 3. By a pulling on the tension 
rod 49 in the direction of the Arrow G, the pressure pulley 12 together 
with the disks 68 and 69 is swivelled. As soon as the disks 68 and 69 come 
to rest against the shaft 3, this contact point, when the tension rod 49 
and the arm 46 are moved further, forms a point of rotation for the lever 
system consisting of the arms 14 and 46. The arm 14 will then swivel 
around the stationary shaft 15 away from the tangential belt 11, the disks 
68 and 69 moving toward the center of the wedge-shaped gap 10. In the 
process, the pressure pulley 12 moves away from the tangential belt 11 so 
that the drive is disengaged. When the tension rod is released again, the 
arms 14 and 46, because of the effect of the leaf spring 16, move back 
into the operating position shown in FIG. 9, in which the disks 68 and 69 
come free of the shaft 3 again while the pressure pulley 12 again biases 
the tangential belt 11. The arm 46 will then rest against stop 66 of the 
arm 14. 
The pressure disks 68 and 69 are advantageously provided with a plastic 
coating. There is, for example, a coating of the material that is known 
under the tradename of "Vulkolan," so that they are applied to the shaft 3 
in a manner that is similar to that of the pairs 4 and 5 of supporting 
disks. 
In a simple development, the disks 68 and 69 are mounted as ring collars on 
the pressure pulley 12. If, however, for constructive reasons, the 
diameter differences between the pressure pulley 12 and the disks 68 and 
69 and thus the difference in their circumferential speeds should become 
larger, it is advantageous to arrange the disks 68 and 69 so that they are 
freely rotatable. 
FIGS. 11 and 12 show an open-end spinning machine 70, having a movable 
servicing apparatus 71, equipped with the bearings and drives for the 
spinning rotor assemblies 1 explained in FIGS. 1 to 10 and the braking 
devices. The open-end spinning machine 70 is provided with driving rails 
73 extending in its longitudinal direction, on which the servicing 
apparatus 71 can be moved by means of running wheels 72. The servicing 
apparatus 71 which may be especially intended for carrying out a piecing 
process after a yarn breakage (in a manner that is not shown in detail) is 
provided with a travelling mechanism which is designed in such a way that 
when servicing is required, the servicing apparatus 71 is applied to the 
spinning unit 74 in need of servicing. The open-end spinning machine 70 
has a plurality of spinning units 74 that are arranged next to one another 
and are identical to one another. A sliver 76 is fed to each spinning unit 
74 from a can 75 which in the spinning unit 74 is spun into a yarn 77 
which is withdrawn via a withdrawal device 78 and is wound onto a spool 79 
which is driven by a drive shaft extending in the longitudinal direction 
of the machine. 
As shown in FIG. 12, each spinning unit 74 is equipped with a partial 
housing 82 that can be swivelled around a shaft 81. The partial housing 
82, in the case of a maintenance requirement, is swivelled away for 
exposing the spinning rotor assembly 1. For this purpose, the servicing 
apparatus 71 has an opening device 83 that can be pivoted around a shaft 
84 and with an opening head 85 is applied to the partial housing 82. The 
servicing apparatus 71 also contains an extending device 86 that can be 
pivoted around a shaft 87 for a head 88. This head 88 contains a brake 
corresponding to the above-described developments, by means of which the 
rotor 2 of the spinning rotor assembly 1 is stopped. In a manner that is 
not shown in detail, the servicing apparatus 71 also contains the 
operating member 40 (see FIG. 2) by means of which the drive of the 
spinning rotor assembly 1 of the concerned spinning unit is interrupted 
and by means of which a pressure disk is applied to the rotor shaft 3. 
Although the invention has been described and illustrated in detail, it is 
to be clearly understood that the above is to be taken by way of 
illustration and example only and not by way of limitation. The spirit and 
scope of the invention are to be limited only by the terms of the appended 
claims.