Note: Descriptions are shown in the official language in which they were submitted.
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Hydrodynamic axial bearing
DESCRIPTION
Field of the Invention
The invention relates to the field of hydrodynamic axial mounting of rotating
shafts, as
are used, for instance, in turbomachines, in particular in exhaust gas
turbochargers.
Prior Art
If rapidly rotating rotors are loaded with axial shearing forces, load-bearing
axial
bearings are used. For example in the case of turbomachines, such as exhaust
gas
turbochargers, hydrodynamic axial bearings are used to absorb axial forces
which are
high as a result of the flow and to guide the shaft in the axial direction. In
order to
improve the oblique position compensation capability and the wear behavior in
applications of this type, disks which float freely in the lubricating oil,
what are known as
floating disks, can be used in hydrodynamic axial bearings between a bearing
comb
which rotates at the shaft rotational speed and a non-rotating axial stop on
the bearing
housing. The lubricating gaps between a rotating bearing comb and the floating
disk
and between the floating disk and the stationary axial stop on the bearing
housing are
advantageously delimited in each case by a profiled circular ring face and a
plane
sliding face which lies opposite the profiled circular ring face. The profiled
circular ring
face serves to optimize the pressure build-up in the lubricating gap, which
pressure
build-up is decisive for the load-bearing force of the axial bearing. In order
to distribute
the lubricating oil which is supplied in the radially inner region of the
profiled circular ring
face, there are lubricating oil grooves which lead radially to the outside.
Wedge faces
which constrict the lubricating gap in the circumferential direction and via
which the
lubricating oil which is introduced into the lubricating oil grooves exits are
formed
adjacently with respect to the lubricating oil grooves. Here, the lubricating
oil is guided
into the wedge face as far as possible over the entire radial height of the
lubricating oil
grooves. The pressure build-up which is necessary for the load-bearing
capability of the
axial bearing takes place substantially in the region of the wedge faces. Rest
faces
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which comprise a planar face and are provided by the load-bearing face of the
profiled
circular ring face are formed adjacently with respect to the wedge faces in
the
circumferential direction.
Examples of axial bearings of this type are found, inter alia, in GB 1095999,
EP0840027, EP1199486, EP1644647 and EP2042753. The radial guidance of the
floating disk takes place either on the rotating body, that is to say on the
shaft or on the
bearing comb by way of a radial bearing which is integrated into the floating
disk, as is
disclosed, for example, in EP0840027, or else on a stationary bearing collar
which
surrounds the rotating body concentrically, as is disclosed, for example, in
EP1199486.
The lubrication of a hydrodynamic axial bearing of this type takes place as a
rule by
means of lubricating oil from a dedicated lubricating oil system or, in the
case of exhaust
gas turbochargers, via the lubricating oil system of an internal combustion
engine which
is connected to the exhaust gas turbocharger.
In the cold state, at a standstill, all the load-bearing faces of conventional
axial
mountings lie perpendicularly with respect to the rotational axis of the rotor
or else at
least parallel to one another. During operation, the load-bearing faces can be
deformed
on account of temperature gradients, centrifugal, shearing and other forces. A
deformation of this type of the bearing load-bearing faces can impair the load-
bearing
force of the mounting. Temperature gradients over the comb of the comb bearing
can
have particularly great effects. The comb which protrudes radially with
respect to the
shaft is deformed in an umbrella-shaped manner on account of the temperature
difference between the load-bearing face and the rear side. This deformation
can lead
to rubbing of the comb bearing on the floating disk, particularly in the case
of a low oil
supply pressure. The deformation on account of the temperature gradient is
particularly
critical in a conventional comb bearing construction, since said deformation
causes a
lubricating gap which widens to the outside. This constellation firstly
reduces the load-
bearing capability for geometric reasons and secondly reduces the centrifugal
force-
induced pressure build-up in the radial direction, since the outflow
resistance for the
lubricating oil radially to the outside is reduced.
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Brief Summary of the Invention
It is therefore an object of the present invention to improve the load-bearing
capability of
a hydrodynamic axial bearing for mounting a shaft which is mounted rotatably
in a
bearing housing.
If the gap which is formed between the load-bearing faces of the axial bearing
is
configured so as to be constricted to the outside in the radial direction, by
the load-
bearing faces being arranged obliquely relative to one another at least in the
radially
outer region, a reduction in the relative oblique position of the load-bearing
faces results
during operation on account of the abovementioned deformation of the rotating
load-
bearing face. The constriction in the radially outer region is reduced, with
the result that
the load-bearing faces rest more uniformly on one another during operation.
If, for instance, the bearing comb is manufactured with a conical load-bearing
face, that
is to say a load-bearing face which is inclined toward the load-bearing face
which lies
opposite it, the temperature deformation in the comb bearing can be
compensated for.
During the compensation, the deformations on account of centrifugal, shearing
and
further forces likewise have to be taken into consideration.
Since the comb bearing deformations are dependent on the operating point, the
lubricating gap becomes smaller in the radial direction under certain
operating
conditions. This situation is more favorable than the current one with a
widened
lubricating gap, since the load-bearing capability is reduced to a lesser
extent and the
centrifugal force-induced pressure build-up in the radial direction is aided.
The compensation on account of load-bearing face deformations as a result of
temperature gradients, centrifugal, shearing and further forces can also take
place at
the floating disk, or at the axial stop of the bearing housing in the case of
an axial
bearing without floating disk. Any temperature-induced deformations which
occur in the
region of the axial stop on the bearing housing can be carried out in a
similar way as on
the comb bearing.
If a floating disk which is conical on both sides or a very thin floating disk
which is
adapted to changing geometric conditions during operation is used, the comb
bearing
deformation can also be compensated for by way of a conical configuration of
the axial
stop on the bearing housing.
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Thanks to the compensation for the deformation, the axial mounting becomes
more
robust at the adjacent bearing parts with respect to rubbing of the floating
disk or the
bearing comb, or, in the case of an axial bearing without floating disk, of
the axial
bearing. The turbocharger becomes more operationally reliable and wear-induced
costs
can be reduced.
Brief Description of the Drawings
In the following text, exemplary embodiments of the invention will be
explained in detail
using drawings, in which:
fig. 1 shows, in the right-hand part, a section which is guided along
the rotational
axis through an embodiment (configured according to the prior art) of an axial
sliding bearing with a rotating bearing comb, a stationary axial stop and a
floating disk, and shows, in the left-hand part, a frontal view in the axial
direction of the corresponding floating disk with a profiled circular ring
face,
fig. 2 shows a diagrammatically illustrated axial sliding bearing
according to fig. 1,
the bearing comb being shown in each case in the cold state in this figure
and in all following figures, and additionally the deformation of the bearing
comb in the operating state on account of the heating and the rapid rotation
and the resulting lubricating gap being indicated by way of dashed lines,
fig. 3 shows a diagrammatically illustrated axial sliding bearing
according to a first
embodiment according to the invention, with a conically shaped bearing
comb and a lubricating gap which results therefrom and tapers radially
toward the outside,
fig. 4 shows a diagrammatically illustrated axial sliding bearing
according to a
second embodiment according to the invention with a floating disk which is
shaped conically on the bearing comb side and a lubricating gap which
results therefrom and tapers radially toward the outside,
fig. 5 shows a diagrammatically illustrated axial sliding bearing
according to a third
embodiment according to the invention, with a conically shaped axial bearing
and conically shaped bearing comb, and two lubricating gaps which result
therefrom and taper radially toward the outside,
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fig. 6
shows a diagrammatically illustrated axial sliding bearing according to a
fourth embodiment according to the invention with a conically shaped axial
bearing and a floating disk which is shaped conically on the bearing comb
side, and two lubricating gaps which result therefrom and taper radially
5 toward the outside,
fig. 7
shows a diagrammatically illustrated axial sliding bearing according to a
fifth
embodiment according to the invention with a floating disk which is shaped
conically on both sides, and two lubricating gaps which result therefrom and
taper radially toward the outside,
fig. 8 shows a diagrammatically illustrated axial sliding bearing according
to a sixth
embodiment according to the invention with a conically shaped bearing comb
and a floating disk which is shaped conically on the axial bearing side, and
two lubricating gaps which result therefrom and taper radially toward the
outside,
fig. 9 shows a diagrammatically illustrated axial sliding bearing according
to a
seventh embodiment according to the invention, without a floating disk, with a
conically shaped bearing comb, and a lubricating gap which results therefrom
and tapers radially toward the outside, and
fig. 10
shows a diagrammatically illustrated axial sliding bearing according to an
eighth embodiment according to the invention, once again without a floating
disk, with a conically shaped axial stop, and a lubricating gap which results
therefrom and tapers radially toward the outside.
Way of Implementing the Invention
Fig. 1 shows by way of example a hydrodynamic axial bearing according to the
prior art,
the three essential components of the axial bearing being made visible in the
right-hand
part of the figure in a section which is guided axially along the rotational
shaft. The
bearing comb 10 is placed on the rotating shaft 40, or is optionally connected
in a
material-to-material manner to the shaft or is produced with the shaft from
one piece,
and rotates with the shaft. A floating disk 30 is arranged axially between an
axial stop
21 on the bearing housing 20 and the bearing comb. In each case one
lubricating gap is
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formed firstly between the axial stop and the floating disk and secondly
between the
floating disk and the bearing comb, in which lubricating gap a thin
lubricating oil layer is
situated between the load-bearing faces. In the embodiment which is shown, the
load-
bearing face 22 on the axial stop and the load-bearing face 11 on the bearing
comb in
15 an embodiment without floating disk, the profiled circular ring face would
correspondingly be arranged on the rotating bearing comb and the planar
sliding face
would be arranged on the axial stop of the bearing housing or at any rate vice
versa,
that is to say the planar sliding face on the rotating bearing comb and the
profiled
circular ring face on the axial stop of the bearing housing.
fig. 1, in which the floating disk is rotated by 90 , with the result that one
of the end
sides of the floating disk can be seen in a plan view.
The profiled circular ring face serves to optimize the pressure build-up in
the lubricating
gap between the load-bearing faces, which pressure build-up is decisive for
the load-
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thick arrows. Here, the lubricating oil is guided into the wedge face 34 as
far as possible
over the entire radial height of the lubricating oil grooves 33. The pressure
build-up
which is necessary for the load-bearing capability of the axial bearing takes
place
substantially in the region of the wedge faces. Rest faces 35 are formed
adjacently with
respect to the wedge faces 34 in the circumferential direction, which rest
faces 35
comprise a planar face which is at the smallest spacing from the corresponding
contact,
as the above-described sliding face. The axial extent (thickness) of the
lubricating gap
can therefore be described as the spacing between the rest faces 35 and the
sliding
face which lies opposite. In order to optimize the pressure build-up in the
radial direction
in the lubricating oil groove and over the wedge faces, the lubricating oil
groove and
wedge face can be closed radially to the outside by way of a web which
constricts the
lubricating gap. Here, the web typically comes to lie as far as the height of
the rest face,
with the result that the rest face and web lie in one plane.
The configuration of the lubricating oil groove and the wedge face is
disregarded for the
embodiments which are described in the following text. Accordingly, the
expressions of
the profiled circular ring face and the sliding face are no longer used in the
following
text. For the practical implementation, however, reference is made to the fact
that the
lubricating gaps, as described above, are advantageously delimited in each
case by a
profiled circular ring face and a planar sliding face. The expression used in
the following
text of the active load-bearing face means that region of the profiled
circular ring face
which is generally called rest face. The rest faces are typically situated so
as to adjoin
the wedge faces as viewed in the flow direction of the lubricating oil.
As indicated in fig. 1 and in the detail which is shown on an enlarged scale
according to
fig. 2, in the cold state, that is to say at a standstill of the rotor, the
load-bearing faces of
the axial mountings are configured perpendicularly with respect to the
rotational axis of
the rotor or else at least parallel to one another. During operation, the load-
bearing face
in the bearing comb can be deformed on account of temperature gradients,
centrifugal,
shearing and further forces. The comb which protrudes radially with respect to
the shaft
is deformed in an umbrella-shaped manner on account of the temperature
difference
between the load-bearing face which is relevant for the axial bearing and the
rear side
which faces away from said load-bearing face. This deformation (indicated in
fig. 2 by
way of dashed lines) can lead to rubbing of the comb bearing on the floating
disk in the
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radially inner region, since the load-bearing force of the lubricating gap
diminishes on
account of the radially outwardly diverging load-bearing faces 31 and 11' of
the axial
bearing and the associated unimpeded escape of the lubricating oil, in
particular in the
case of a low oil supply pressure, at which sufficient lubricating oil cannot
be
replenished.
Fig. 3 shows a diagrammatically illustrated hydrodynamic axial sliding bearing
according
to a first embodiment according to the invention. Here, the active load-
bearing face 31
on that side of the floating disk 30 which faces the bearing comb is oriented
strictly
radially, that is to say perpendicularly with respect to the rotational axis
of the shaft 40.
In contrast, the load-bearing face 11 of the bearing comb is shaped so as to
be inclined
toward the floating disk 30, which results in a constriction in the axial
direction in the
radially outer region of the lubricating gap 52. In this embodiment, just as
in the further
embodiments which will be described in the following text, the inclination of
the load-
bearing face 11 of the bearing comb can be realized by way of a uniform,
straight
inclination or by way of a curved inclination. In the figures, the
deformations of the
rotating components and the constrictions of the lubricating gaps are
illustrated in a
greatly exaggerated manner. In fact, the inclination angles which are provided
according
to the invention move over the entire radius of the inclined component in the
range of a
few hundredths of a degree, which results in a constriction of the lubricating
gap at the
radially outer edge of a few hundredths of a millimeter in the case of a disk
with a
diameter of 200 mm. During operation, a deformation of the bearing comb which
is once
again indicated by way of dashed lines results on account of the above-
described
heating of the bearing comb and as a result of the action of the stated
forces. According
to the invention, the load-bearing face 11, which is inclined towards the
floating disk in
the cold state, of the bearing comb stretches in such a way that the angle of
the
constriction of the lubricating gap 52' is reduced during nominal operation
and the two
load-bearing faces 31 and 11' of the bearing run parallel to one another or,
while
maintaining a lubricating gap constriction which is less pronounced than in
the cold
state, run at least virtually parallel to one another. The fact that, in the
cold state, that is
to say at a standstill and also at small rotational speeds, the configuration
according to
the invention of the axial sliding bearing leads to a constriction of the
lubricating gap in
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the radial outer region is not a problem, since the accumulated lubricating
oil ensures an
additional pressure build-up.
Fig. 4 shows a diagrammatically illustrated hydrodynamic axial sliding bearing
according
to a second embodiment according to the invention. Here, the load-bearing face
11 of
the bearing comb is oriented strictly radially, that is to say perpendicularly
with respect
to the rotational axis of the shaft 40. For this purpose, the load-bearing
face 31 on that
side of the floating disk 30 which faces the bearing comb is configured so as
to be
inclined toward the bearing comb 10 in this embodiment, which results once
again in the
constriction in the axial direction in the radially outer region of the
lubricating gap 52.
The floating disk is therefore of conical configuration on the side which
faces the
bearing comb, whereas it is oriented perpendicularly with respect to the
rotational axis
of the shaft 40 on the other side which faces the axial stop on the bearing
housing.
During operation, a deformation of the bearing comb which is once again
indicated by
way of dashed lines results on account of the above-described heating of the
bearing
comb and as a result of the action of the stated forces. According to the
invention, the
load-bearing face 11, which is oriented perpendicularly with respect to the
rotational
axis of the shaft 40 in the cold state, of the bearing comb is bent in such a
way that,
during nominal operation, the angle of the constriction of the lubricating gap
52' is
reduced and the two load-bearing faces 31 and 11' of the bearing run parallel
or virtually
parallel to one another.
In the embodiments according to figs. 5 to 8, in addition to the lubricating
gap 52
between the floating disk 30 and the bearing comb 10, the lubricating gap 51
between
the axial stop 21 and the floating disk 30 is also configured with a
constriction in the
axial direction in the radially outer region.
Fig. 5 shows a diagrammatically illustrated hydrodynamic axial sliding bearing
according
to a third embodiment according to the invention. Here, the load-bearing face
31 is
oriented strictly radially on that side of the floating disk 30 which faces
the bearing
comb, that is to say perpendicularly with respect to the rotational axis of
the shaft 40. In
contrast, the load-bearing face 11 of the bearing comb is shaped such that it
is inclined
toward the floating disk 30, which results in a constriction in the axial
direction in the
radially outer region of the lubricating gap 52. The second lubricating gap
which is
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likewise provided with a constriction in the axial direction in the radially
outer region
extends between the load-bearing face 32 which is oriented strictly radially,
that is to
say perpendicularly with respect to the rotational axis of the shaft 40, on
that side of the
floating disk 30 which faces the axial stop and the load-bearing face 22 of
the axial stop
5 21 on the bearing housing, which load-bearing face 22 is inclined toward
the floating
disk 30. The floating disk is therefore provided with two sides which run
parallel to one
another and are oriented perpendicularly with respect to the rotational axis
of the shaft
40. During operation, a deformation of the bearing comb 10 which is once again
indicated by way of dashed lines results on account of the above-described
heating of
10 the bearing comb and as a result of the action of the stated forces.
According to the
invention, the load-bearing face 11, which is inclined toward the floating
disk in the cold
state, of the bearing comb stretches in such a way that, during nominal
operation, the
angle of the constriction of the lubricating gap 52' is reduced and the two
load-bearing
faces 31 and 11' of the bearing run parallel to one another or virtually
parallel to one
another.
Fig. 6 shows a diagrammatically illustrated hydrodynamic axial sliding bearing
according
to a fourth embodiment according to the invention, which hydrodynamic axial
sliding
bearing differs from the preceding one in that the load-bearing face 11 of the
bearing
comb is oriented strictly radially, that is to say perpendicularly with
respect to the
rotational axis of the shaft 40, and, for this purpose, the load-bearing face
31 is
configured so as to be inclined toward the bearing comb 10 on that side of the
floating
disk 30 which faces the bearing comb. The second lubricating gap which is
likewise
provided with a constriction in the axial direction in the radially outer
region once again
extends between the load-bearing face 32 which is oriented strictly radially,
that is to
say perpendicularly with respect to the rotational axis of the shaft 40, on
that side of the
floating disk which faces the axial stop and the load-bearing face 22 of the
axial stop 21
on the bearing housing, which load-bearing face 22 is inclined toward the
floating disk
30. The floating disk is therefore of conical configuration on the side which
faces the
bearing comb, whereas it is oriented perpendicularly with respect to the
rotational axis
of the shaft 40 on the other side which faces the axial stop on the bearing
housing.
During operation, a deformation of the bearing comb which is once again
indicated by
way of dashed lines results on account of the above-described heating of the
bearing
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comb and as a result of the action of the stated forces. According to the
invention, the
load-bearing face 11, which is oriented perpendicularly with respect to the
rotational
axis of the shaft 40 in the cold state, of the bearing comb bends in such a
way that,
during nominal operation, the angle of the constriction of the lubricating gap
52' is
reduced and the two load-bearing faces 31 and 11' of the bearing run parallel
to one
another or virtually parallel to one another.
Fig. 7 shows a diagrammatically illustrated hydrodynamic axial sliding bearing
according
to a fifth embodiment according to the invention. Here, the load-bearing face
11 of the
bearing comb is oriented strictly radially, that is to say perpendicularly
with respect to
the rotational axis of the shaft 40. In contrast, on that side of the floating
disk 30 which
faces the bearing comb, the load-bearing face 31 is configured so as to be
inclined
toward the bearing comb 10, which results in a constriction in the axial
direction in the
radially outer region of the lubricating gap 52. The second lubricating gap
which is
likewise provided with a constriction in the axial direction in the radially
outer region
extends between the load-bearing face, which is oriented strictly radially,
that is to say
perpendicularly with respect to the rotational axis of the shaft 40, of the
axial stop 21 on
the bearing housing and the load-bearing face 32 which is inclined toward the
axial stop
on that side of the floating disk which faces the axial stop. The floating
disk 30 is
therefore configured so as to be conical on both sides. During operation, a
deformation
of the bearing comb 10 which is once again indicated by way of dashed lines
results on
account of the above-described heating of the bearing comb and as a result of
the
action of the stated forces. According to the invention, the load-bearing face
11, which is
oriented perpendicularly with respect to the rotational axis of the shaft 40
in the cold
state, of the bearing comb bends in such a way that, during nominal operation,
the
angle of the constriction of the lubricating gap 52' is reduced and the two
load-bearing
faces 31 and 11' of the bearing run parallel to one another or virtually
parallel to one
another.
Fig. 8 shows a diagrammatically illustrated hydrodynamic axial sliding bearing
according
to a sixth embodiment according to the invention, which hydrodynamic axial
sliding
bearing differs from the preceding one in that the load-bearing face 31 on
that side of
the floating disk 30 which faces the bearing comb is oriented strictly
radially, that is to
say perpendicularly with respect to the rotational axis of the shaft 40, and,
for this
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purpose, the load-bearing face 11 of the bearing comb is shaped so as to be
inclined
toward the floating disk 30, which results once again in a constriction in the
axial
direction in the radially outer region of the lubricating gap 52. The second
lubricating
gap which is likewise provided with a constriction in the axial direction in
the radially
outer region once again extends between the load-bearing face 22, which is
oriented
strictly radially, that is to say perpendicularly with respect to the
rotational axis of the
shaft 40, of the axial stop 21 on the bearing housing and the load-bearing
face 32 which
is inclined toward the axial stop on that side of the floating disk which
faces the axial
stop. The floating disk is therefore of conical configuration on the side
which faces the
axial stop on the bearing housing, whereas it is oriented perpendicularly with
respect to
the rotational axis of the shaft 40 on the other side which faces the bearing
comb.
During operation, a deformation of the bearing comb which is once again
indicated by
way of dashed lines results on account of the above-described heating of the
bearing
comb and as a result of the action of the stated forces. According to the
invention, the
load-bearing face 11, which is inclined toward the floating disk in the cold
state, of the
bearing comb stretches in such a way that, during nominal operation, the angle
of the
constriction of the lubricating gap 52' is reduced and the two load-bearing
faces 31 and
11' of the bearing run parallel to one another or virtually parallel to one
another.
The two last figures in each case show a hydrodynamic axial sliding bearing
without a
floating disk, in which a load-bearing face 12 is arranged on the rotating
bearing comb
10 and a load-bearing face 22 is arranged on the axial stop 21 of the bearing
housing
20. According to the invention, the lubricating gap 53 which results between
them is
once again configured so as to converge radially to the outside, that is to
say the
lubricating gap tapers in the radially outer region.
The seventh embodiment according to the invention (shown in fig. 9) of a
hydrodynamic
axial sliding bearing has a load-bearing face 12 of the bearing comb 10, which
load-
bearing face 12 is shaped so as to be inclined toward the axial stop 21 of the
bearing
housing 20, which results in the constriction in the axial direction in the
radially outer
region of the lubricating gap 53. The load-bearing face 22 of the axial stop
21 of the
bearing housing 20 is oriented strictly radially, that is to say
perpendicularly with respect
to the rotational axis of the shaft 40, in this embodiment. During operation,
once again a
deformation of the bearing comb which is once again indicated by way of dashed
lines
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results on account of the above-described heating of the bearing comb and as a
result
of the action of the stated forces. According to the invention, the load-
bearing face 12,
which is inclined toward the load-bearing face of the axial stop 21 in the
cold state, of
the bearing comb stretches in such a way that, during nominal operation, the
angle of
the constriction of the lubricating gap 53' is reduced and the two load-
bearing faces 12'
and 22 of the bearing run parallel to one another or virtually parallel to one
another.
The eighth embodiment according to the invention (shown in fig. 10) of a
hydrodynamic
axial sliding bearing has a load-bearing face 12 of the bearing comb 10, which
load-
bearing face 12 is oriented strictly radially, that is to say perpendicularly
with respect to
the rotational axis of the shaft 40. For this purpose, in this embodiment, the
load-bearing
face 22 of the axial stop 21 on the bearing housing 20 is configured so as to
be inclined
toward the bearing comb 10, which results once again in the constriction in
the axial
direction in the radially outer region of the lubricating gap 53. The axial
stop is therefore
of conical configuration on the side which faces the bearing comb. During
operation,
once again a deformation of the bearing comb which is once again indicated by
way of
dashed lines results on account of the above-described heating of the bearing
comb
and as a result of the action of the stated forces. According to the
invention, the load-
bearing face 12, which is oriented perpendicularly with respect to the
rotational axis of
the shaft 40 in the cold state, of the bearing comb 10 bends in such a way
that, during
nominal operation, the angle of the constriction of the lubricating gap 53' is
reduced and
the two load-bearing faces 12' and 22 of the bearing run parallel to one
another or
virtually parallel to one another.
In all the embodiments, in each case one of the load-bearing faces is
described as
deviating from the plane which is oriented perpendicularly with respect to the
rotational
axis of the shaft and the other load-bearing face is described as running
strictly radially,
that is to say along precisely this plane which is oriented perpendicularly
with respect to
the rotational axis of the shaft. According to the invention, the narrowing
lubricating
gaps can also be realized by the respective load-bearing faces both deviating
from
respective planes which are oriented perpendicularly with respect to the
rotational axis
of the shaft, but being at an angle with respect to one another. For example,
in the
embodiment with a floating disk, both the load-bearing face on that side of
the floating
disk which faces the bearing comb and the load-bearing face on the bearing
comb can
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run so as to be inclined toward the lubricating gap in comparison with the
plane which is
oriented perpendicularly with respect to the rotational axis of the shaft, and
can thus
delimit the narrowing lubricating gap.
Even if in each case only load-bearing faces were mentioned in all the
abovementioned
embodiments, it is to be noted once again here that, if one or both of the
components
which delimit a respective lubricating gap have a profiled surface with a
lubricating oil
groove, wedge faces and rest faces, the expression load-bearing face means in
each
case that region of the profiled surface which is called rest face. In the
absence of a rest
face, the load-bearing face extends along the maximum elevation of the wedge
faces in
the transition region to the respectively next lubricating oil groove.
CA 02852164 2014-04-14
15 CH-11 135-WO
List of Designations
Bearing comb
11, 12 Load-bearing face on the bearing comb
11', 12' Load-bearing face on the bearing comb (in the operating state)
Bearing housing
21 Axial stop
22 Sliding face
Floating disk
31, 32 Load-bearing face of the floating disk
33 Lubricating oil groove
34 Wedge face
Rest face
Shaft
51 Lubricating gap between the axial stop and the floating disk
52 Lubricating gap between the floating disk and the bearing comb
52' Lubricating gap between the floating disk and the bearing comb (in
the
operating state)
53 Lubricating gap between the axial stop and the bearing comb
53' Lubricating gap between the axial stop and the bearing comb (in the
operating
state)
