U.S. patent application number 10/439726 was filed with the patent office on 2004-01-29 for sliver delivery and opening device.
This patent application is currently assigned to W. Schlafhorst AG & Co.. Invention is credited to Dressen, Jochen, Haaken, Dieter, Rademacher, Wolfgang, Schelter, Detlef, Spitzer, Michael, Welters, Norbert.
Application Number | 20040016224 10/439726 |
Document ID | / |
Family ID | 29265369 |
Filed Date | 2004-01-29 |
United States Patent
Application |
20040016224 |
Kind Code |
A1 |
Haaken, Dieter ; et
al. |
January 29, 2004 |
Sliver delivery and opening device
Abstract
A sliver delivery and opening device having a pivotably seated
sliver intake cylinder driven by a worm gear arrangement comprising
a worm wheel connected to the sliver intake cylinder that meshes
with a worm affixed to a drive shaft. The worm includes thread
windings conforming to a superimposed profile that axially offsets
the worm relative to the worm wheel, thus preventing placement of a
tooth of the worm wheel on a thread head of the worm when the worm
wheel pivotally engages the worm. The amount of offset is measured
between a plane of symmetry intersecting the superimposed profile
of the worm thread windings and a pivot plane intersecting a center
axis of the worm wheel. A positioning device, comprising at least
one magnet and a ferromagnetic positioning element, prepositions
the worm wheel relative to the pivot plane for pivotal engagement
of the worm wheel and the worm.
Inventors: |
Haaken, Dieter; (Erkelenz,
DE) ; Spitzer, Michael; (Korschenbroich, DE) ;
Schelter, Detlef; (Herzogenrath, DE) ; Rademacher,
Wolfgang; (Wegberg, DE) ; Welters, Norbert;
(Monchengladbach, DE) ; Dressen, Jochen;
(Schwalmtal, DE) |
Correspondence
Address: |
KENNEDY COVINGTON LOBDELL & HICKMAN, LLP
214 N. TRYON STREET
HEARST TOWER, 47TH FLOOR
CHARLOTTE
NC
28202
US
|
Assignee: |
W. Schlafhorst AG & Co.
Monchengladbach
DE
|
Family ID: |
29265369 |
Appl. No.: |
10/439726 |
Filed: |
May 16, 2003 |
Current U.S.
Class: |
57/408 |
Current CPC
Class: |
D01H 4/42 20130101; D01H
4/32 20130101 |
Class at
Publication: |
57/408 |
International
Class: |
D01H 004/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 18, 2002 |
DE |
102 22 291.6 |
Claims
What is claimed is:
1. A sliver delivery and opening device for an open-end spinning
machine, the sliver deliver and opening device comprising: a
pivotable sliver intake cylinder; a worm gear arrangement having a
worm wheel connected to the sliver intake cylinder and a worm
mountable on a fixedly supported rotatable shaft extending along
the machine, the worm wheel having a plurality of teeth and the
worm having thread windings with a threading contour conforming to
a superimposed profile for preventing placement of a tooth of the
worm wheel on a thread head of the worm, the worm being fixable on
the rotatable shaft to present a plane of symmetry that is offset
in an axial direction of the rotatable shaft with respect to a
pivot plane of a center axis of the worm wheel, is perpendicular
relative to the rotatable shaft, and intersects a valley of the
superimposed profile centered between two adjacent threads of the
worm; and a positioning device for prepositioning the worm wheel as
a function of the offset of, the worm to facilitate the pivoting of
the teeth of the worm wheel into the worm.
2. A sliver delivery and opening device according to claim 1,
characterized in that one tooth of the plurality of teeth of the
worm wheel is positioned such that the centerline of the one tooth
lies at a predetermined positioning angle .phi. relative to the
pivot plane of the worm wheel, wherein the positioning angle .phi.
is a function of the offset of the worm measured between the plane
of symmetry and the pivot plane.
3. A sliver delivery and opening device according to claim 2,
wherein the positioning angle .phi. is calculated by an equation:
.phi.=72* sin(X/2), where X is the offset of the worm.
4. A sliver delivery and opening device according to claim 1,
characterized in that the positioning device comprises at least one
magnet fixed in place on a bearing housing of an electromagnetic
coupling attached to a shaft of the sliver intake cylinder, and a
ferromagnetic positioning element that is connected, and fixed
against relative rotation, to the worm wheel.
5. A sliver delivery and opening device according to claim 4,
wherein the at least one magnet of the positioning device comprises
at least one permanent magnet.
6. A sliver delivery and opening device according to claim 4,
wherein the positioning element comprises a positioning disk having
a number of radially protruding ferromagnetic positioning shoulders
disposed thereon.
7. A sliver delivery and opening device according to claim 6,
wherein the number of ferromagnetic positioning shoulders
corresponds to a total number of teeth that comprise the plurality
of teeth of the worm wheel.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of German Patent
Application No. 10222291.6, filed May 18, 2002, hereby incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a sliver delivery and
opening device for an open-end spinning machine having a sliver
intake cylinder selectively operable by a worm gear
arrangement.
[0003] Sliver delivery and opening devices for open-end spinning
machines are part of the prior art. During spinning operations, the
open-end spinning devices are closed by a pivotably seated cover
element that has attached to it the sliver delivery and opening
device. These cover elements generally have a bearing bracket for a
sliver opening roller and a bearing bracket for a sliver intake
cylinder. A worm wheel, which along with a worm constitutes the
worm gear arrangement, is affixed to an end of a rotatable shaft
supporting the sliver intake cylinder and selectively engages the
worm by means of an electromagnetic coupling that is also disposed
on the shaft of the sliver intake cylinder. With the open-end
spinning device closed, the worm wheel meshes with the worm, which
is fixed on a drive shaft of the rotor spinning machine that
extends over the length of the machine and is continuously
rotating. When the open-end spinning device is open, the worm wheel
and the worm are spaced apart, thus disengaging the worm wheel from
the worm.
[0004] The above disclosed driving of a sliver intake cylinder has
been successful, in principle, in actual use. However, difficulties
can occasionally arise in the course of repositioning the worm
wheel in the worm during engagement of the worm wheel with the
worm. Such difficulties are evidenced by an increased wear of the
worm wheel.
[0005] Overcoming such difficulties has been attempted. For
example, in an open-end spinning device, described in German Patent
Publication DE-AS 23 14 229, a pivot housing having a sliver intake
cylinder and a sliver opening roller attached thereto, is seated on
a separate pivot shaft spatially separated from the drive shaft
extending over the length of the machine. The sliver intake
cylinder, whose axis of rotation is parallel to the center axis of
the drive shaft extending over the length of the machine, is
connected to the drive shaft extending over the length of the
machine by a special intermediate shaft that has a gear wheel on
each of its ends. Upon opening the open-end spinning device, one of
the gear wheels of the intermediate shaft slides out of a
corresponding gear wheel fixedly installed on the drive shaft
extending over the length of the machine. In order to minimize
meshing and friction resistance occurring between the gear wheels
when the open-end spinning device is closed, the pivot shaft, the
drive shaft extending over the length of the machine, and the
intermediate shaft are arranged such that while closing the
open-end spinning device, an approximately tangential sliding of
the gear wheel on the intermediate shaft onto the gear wheel of the
drive shaft extending over the length of the machine takes
place.
[0006] However, the above disclosed open-end spinning device, which
is relatively complicated in its structure, has not proven itself
in actual use and, hence, has not gained acceptance in the textile
industry.
[0007] An open-end spinning device, having a pivotably seated cover
element into which a sliver intake cylinder and a sliver opening
roller are integrated and whose pivot shaft is arranged spaced
apart from a drive shaft extending over the length of the machine,
is also described in European Patent Publication EP 0 672 767 A1.
With this known open-end spinning device, the sliver intake
cylinder is driven by a worm wheel meshing with a worm that is
fixed in place on a constantly rotating drive shaft extending over
the length of the machine. With the open-end spinning device
closed, the worm wheel of the sliver intake cylinder engages the
corresponding worm, and with the open-end spinning device opened
the worm wheel is spaced apart from the worm. In order to assure
the correct operation of the sliver intake cylinder, the worm wheel
and the worm commonly have the same pitch. In particular, the pitch
of the worm wheel at the reference diameter relevant for the drive
corresponds exactly to the pitch of the worm thread windings.
[0008] However, the disclosed arrangement results in the pitch of
the worm wheel at the tip diameter being greater than the pitch of
the worm thread so that, when the worm wheel is pivoted into and
engages the worm, it is possible for two teeth of the worm wheel to
simultaneously extend over two thread windings of the worm, thus
preventing any further pivoting engagement of the worm wheel with
the worm.
[0009] To overcome this disadvantage, and to ease the pivotal
engagement of the worm wheel into the worm when the open-end
spinning device is closed, it is provided in accordance with
European Patent Publication EP 0 672 767 A1 to equip the worm
thread windings with a special threading contour and to arrange the
worm on the drive shaft such that a plane of symmetry of the
worm--established by the threading contour--exactly corresponds to
the pivot plane of the center axis of the worm wheel. In
particular, the worm thread is given a superimposed profile, whose
pitch exactly corresponds to the pitch of the worm wheel at the tip
circle and which is laid out and arranged in such a way that the
thread windings of the worm always end in a tip. The disclosed
configuration assures that one of the teeth of the worm wheel
enmeshes between two thread windings of the worm when the worm
wheel pivotally engages and meshes with the worm.
[0010] However, actual use has shown that, although the correct
enmeshing of the worm wheel into the worm is assured by worm gear
arrangements designed and arranged in the disclosed configuration,
such worm gear arrangements no longer have an optimal bearing
behavior because of the reduction of the effective contact surfaces
in the area of the thread windings of the worm. In particular, the
worm wheel of such designed configured worm gear arrangements no
longer rotates uniformly. Furthermore, the individual teeth of the
worm wheel are subjected to more stresses than with conventional
worm gear arrangements. The uneven rotation of the worm wheel leads
to fluctuations in the sliver intake, while the great stress on the
worm wheel teeth leads to increased wear of the worm wheel.
SUMMARY OF THE INVENTION
[0011] The present invention addresses the above discussed
disadvantages by providing a sliver intake cylinder that is
selectively operable by a worm gear arrangement in which a plane of
symmetry intersecting a superimposed profile of the worm thread
windings is axially offset from a pivot plane intersecting the
center axis of the worm wheel, and a positioning device that
positions the worm wheel as a function of the amount of offset of
the plane of symmetry relative to the pivot plane prior to pivotal
engagement of the worm.
[0012] The present invention has the particular advantage of
providing a uniform rotation of the sliver intake cylinder and
increasing the service life of the worm wheel while assuring that
the worm wheel pivotally engages and meshes with the rotating worm
during the closing of the open-end spinning device. Notably, the
present invention improves the bearing behavior of the worm gear
arrangement by means of the axial offset of the worm provided with
a superimposed profile on its drive shaft, i.e. by displacing the
worm orthogonally in relation to the pivot plane of the worm wheel,
which has a positive effect on the rotation of the sliver intake
cylinder, as well as on the service life of the worm wheel.
[0013] To assure the correct pivotal engagement of the worm wheel
into the offset worm, a positioning device is provided to
consistently preposition the worm wheel relative to the worm such
that two teeth of the worm wheel are prevented from simultaneously
covering two adjacent thread windings of the worm.
[0014] In a preferred embodiment, the positioning device locates
the centerline of one of the teeth of the worm wheel at a preset
positioning angle relative to the pivot plane of the center axis of
the worm wheel. In particular, the positioning angle is a function
of the amount of the offset of the worm and is calculated such that
the worm wheel pivotally engages the worm in a consistent
manner.
[0015] The angularly correct alignment of the teeth of the worm
gear arrangement assures that no seizing or similar interference
between the worm wheel and the worm occur when the worm wheel
pivotally engages the worm. In particular, as already explained
above, the propositioning dependably prevents two teeth of the worm
wheel from being simultaneously placed over two adjoining thread
windings of the worm.
[0016] In a preferred embodiment, the positioning device comprises
at least one magnet that is affixed on the bearing housing of the
electromagnetic coupling, and a ferromagnetic positioning element
that is connected, and fixed against relative rotation thereof, to
the worm wheel of the worm gear arrangement; the positioning
element being decoupled from, and freely rotatable relative
thereto, the sliver intake cylinder when the open-end spinning
device is opened. Preferably, the at least one magnet of the
positioning device comprises at least one permanent magnet. Such a
permanent magnet does not require any additional energy supply,
while providing the correct dependable alignment of the positioning
element, and therefore a dependable setting of the angular position
of the teeth of the worm wheel.
[0017] In a preferred embodiment, the positioning element of the
present invention comprises a positioning disk having a plurality
of radially protruding positioning shoulders, each of which is
acted upon by the magnetic force of the at least one magnet of the
positioning device. Thus, when the worm wheel pivotally engages the
worm, the positioning shoulders cooperating with the at least one
magnet consistently provides a preset, angularly correct alignment
of the teeth of the worm wheel. The number of centering shoulders
of the positioning disk preferably corresponds to the number of
teeth of the worm wheel. Such correspondence ensures that one of
the positioning shoulders is constantly located within the
effective range of the magnet and is pivoted by it into the desired
position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Further features, embodiments, and advantages of the present
invention will become apparent from the following detailed
description with reference to the drawings, wherein:
[0019] FIG. 1 is a schematic of an open-end spinning device with a
pivotably seated cover element having an integral sliver delivery
and opening device in a closed, operating configuration;
[0020] FIG. 2 is a schematic of an open-end spinning device similar
to that of FIG. 1, the open-end spinning device in an opened,
non-operating configuration;
[0021] FIG. 3 is a partial cutaway view of the worm gear
arrangement operating the sliver intake cylinder, illustrating the
positioning device of the present invention that provides an
angularly correct alignment of the teeth of the worm wheel, the
worm wheel being spaced apart and disengaged from the worm; and
[0022] FIG. 4 is an elevational view of the worm gear arrangement
similar to that of FIG. 3, illustrating the worm gear arrangement
in a operating configuration, the worm wheel being in pivotal
engagement with the worm.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Referring now to FIGS. 1 and 2, an open-end spinning device
1 in a rotor spinning machine comprises a spinning box housing 2
fixed in place on a base frame of the rotor spinning machine (not
shown in detail), by fastening means 3. Typically, a bracket 4
fastened on the spinning box housing 2 supports a support ring
bearing 5, an axial bearing 6, and a rotor housing 7. The rotor
housing 7 is connected via a pneumatic line 8 to a vacuum source 9
for establishing a vacuum within the rotor housing 7.
[0024] A spinning rotor 10 located inside the rotor housing 7
rotates at high speed during the operation of spinning. Spinning
rotor 10 is supported by rotor shaft 11 seated in wedge gaps of the
support ring bearing 5. The spinning rotor 10 is typically driven
by a tangential belt 12 applied to the rotor shaft 11 by a tension
pulley 13.
[0025] The rotor housing 7 is open toward a front of the open-end
spinning device 1. During operation, the rotor housing 7 is closed
by a fiber conduit plate 15 attached to a cover element 14. When
covering the rotor housing 7, the cover element 14 rests against
the front of the rotor housing 7. The cover element 14 rotates
about a pivot shaft 19 to move away from the open end of the rotor
housing 7, thus opening the rotor housing 7. The fiber conduit
plate 15 preferably has an exchangeable fiber conduit plate adapter
16, attached thereto. A yarn withdrawal nozzle 17 and a mouth of a
fiber guide conduit 18, are arranged in the fiber conduit plate
adapter 16.
[0026] The open-end spinning device 1 also includes a sliver
delivery and opening device 20 integral to the cover element 14.
The sliver delivery and opening device 20 comprises a sliver intake
cylinder 21 and a sliver opening roller 26. The sliver intake
cylinder 21 is connected via a worm gear arrangement, comprising a
worm wheel 22 and a worm 23, with a constantly rotating drive shaft
24 extending over the length of the machine. In particular, the
worm wheel 22 is fastened at an end of shaft 36 of the sliver
intake cylinder 21 and meshes with the worm 23 attached to the
rotatable drive shaft 24. A magnetic coupling 25 connected to the
shaft 36 selectively separates the worm wheel 22 from the sliver
intake cylinder 21 when required. As shown in FIGS. 1 and 2, the
sliver opening roller 26 is driven by a continuously rotating
tangential belt 28 applied to a driving wharve 27 that is affixed
to a back of the sliver opening roller 26.
[0027] FIG. 1 shows the open-end spinning device 1 during the
spinning operation wherein the rotor housing 7 is closed by the
cover element 14. In this operating state, the worm wheel 22 of the
sliver intake cylinder 21 is enmeshed with the worm 23 which is
connected with the rotating drive shaft 24, and the driving wharve
27 of the sliver opening roller 26 rests against the rotating
tangential belt 28.
[0028] FIG. 2 shows the corresponding open-end spinning device 1
when not in operation. As illustrated in FIG. 2, the cover element
14 of the open-end spinning device 1 is pivoted around the pivot
shaft 19 in the direction of the arrow A, thus opening the rotor
housing 7. With the rotor housing 7 opened in this manner, the
rotor housing 7 is easily accessible, for example for cleaning the
spinning rotor 10.
[0029] When the cover element 14 is pivoted away from the rotor
housing 7, the driving wharve 27 of the sliver opening roller 26 is
lifted off the tangential belt 28, and the worm wheel 22 of the
sliver intake cylinder 21 is disengaged and spaced apart from the
worm 23 on the fixedly arranged drive shaft 24. A path followed by
the worm wheel 22 during the opening of the open-end spinning
device 1 is shown by dashed line S in FIG. 2.
[0030] The worm gear arrangement, i.e., the worm wheel 22 and the
worm 23, is illustrated in FIGS. 3 and 4. In particular, FIG. 3
shows the worm wheel 22 slightly spaced apart from the worm 23,
which would be the configuration just before the worm wheel 22
pivotally engages and meshes with the worm 23 as the rotor housing
7 is being closed by the cover element 14. FIG. 4 shows the worm
wheel 22 fully enmeshed with the worm 23, which would be the
configuration during spinning operations.
[0031] As shown in FIGS. 3 and 4, the worm wheel 22 is affixed to
an end of the shaft 36 of the sliver intake cylinder 21. The worm
wheel 22 comprises a plurality of teeth 32 at spaced intervals
along a circumference of the worm wheel 22, the plurality of the
teeth 32 projecting outwardly from a center axis 44 of the worm
wheel 22. A reference circle 39 provides a pitch t and a tooth tip
circle 38 provides a pitch T for the plurality of teeth 32 of the
worm wheel 22. A pivot plane 43 perpendicular to the rotating drive
shaft 24 upon which the worm 23 is affixed intersects the center
axis 44 of the worm wheel 22.
[0032] The worm 23 is affixed on the rotating drive shaft 24 that
extends over the length of the machine. The worm has thread
windings 41 that have a trapezoidal cross-section with pitch t. A
profile 40 is superimposed over a contour of the thread windings,
41, the superimposed profile 40 having a defined shape with a
plurality of alternating peaks and valleys. The superimposed
profile 40 has a pitch T corresponding to the pitch T measured at
the tooth tip circle 38 of the worm wheel 22. The superimposed
profile 40 is laid over the thread windings 41 such that each of
the thread windings 41 terminates in a clearance lip. A plane of
symmetry 42 perpendicular to the rotating drive shaft 24 intersects
one valley of the alternating peaks and valleys of the superimposed
profile 40 that is centered between two adjacent thread windings
41.
[0033] In the present invention, as shown in FIG. 3, as the worm
wheel 22 is pivoted toward engagement of the worm 23, a centerline
33 of one tooth of the plurality of teeth 32 of the worm wheel 22
is constantly held at a positioning angle .phi. relative to the
pivot plane of the worm wheel 22. The positioning angle .phi. is a
function of an amount of offset X of the worm 23 wherein the amount
of offset X is the distance between the plane of symmetry 42 of the
worm 23 and the pivot plane 43 of the worm wheel 22, as shown in
FIG. 3. Preferably, the positioning angle .phi. is calculated by
the equation:
.phi.=72* sin(X/2)
[0034] To maintain the centerline 33 of the one tooth at
positioning angle p during pivotal engagement of the worm wheel 22
with the worm 23, the present invention employs a positioning
device 30. The positioning device 30 comprising a magnet 37,
preferably a permanent magnet, that is affixed, for example, on a
bearing housing 31 of the electromagnetic coupling 25, and
ferromagnetic positioning element 34 that is connected to the worm
wheel 22 such that the positioning element 34 is fixed against
rotation relative to the worm wheel 22.
[0035] In a preferred embodiment, the positioning element 34 is a
disk having radially protruding positioning shoulders 35 thereon.
The magnet 37 is situated relative to the positioning shoulders 35
such that the magnet 37 acts upon the positioning shoulders 35 to
maintain the plurality of teeth 32 of the worm wheel 22 at a
desired position relative to the worm 23. In particular, the
positioning device 30 maintains the centerline 33 of one tooth of
the plurality of teeth 32 of the worm wheel 22 at the positioning
angle .phi., as shown in FIG. 3.
[0036] The worm gear arrangement of the present invention, having
the worm 23 axially offset relative to the worm wheel 22 by the
amount of offset X, exhibits uniform rotation of the worm wheel 22
upon the worm 23, resulting in an even operation of the sliver
intake cylinder 21 and subsequently a smooth sliver intake.
Further, use of the positioning device 30 to position the worm
wheel 22 relative to the worm 23 during pivotal engagement of the
worm wheel 22 prevents two teeth of the plurality of teeth 32 of
the worm wheel 22 from simultaneously extending over two adjacent
thread windings 41 of the worm 23. This precludes any resultant
interference with closing the rotor housing 7 of the open-end
spinning device 1 and minimizes wear of the worm wheel 22.
[0037] It will therefore be readily understood by those persons
skilled in the art that the present invention is susceptible of
broad utility and application. Many embodiments and adaptations of
the present invention other than those herein described, as well as
many variations, modifications and equivalent arrangements, will be
apparent from or reasonably suggested by the present invention and
the foregoing description thereof, without departing from the
substance or scope of the present invention. Accordingly, while the
present invention has been described herein in detail in relation
to its preferred embodiment, it is to be understood that this
disclosure is only illustrative and exemplary of the present
invention and is made merely for purposes of providing a fill and
enabling disclosure of the invention. The foregoing disclosure is
not intended or to be construed to limit the present invention or
otherwise to exclude any such other embodiments, adaptations,
variations, modifications and equivalent arrangements, the present
invention being limited only by the claims appended hereto and the
equivalents thereof.
* * * * *