U.S. patent application number 10/155635 was filed with the patent office on 2002-12-12 for sliding ring for a radial piston pump, and device for the installation thereof.
Invention is credited to Herrmann, Michael.
Application Number | 20020185002 10/155635 |
Document ID | / |
Family ID | 7686527 |
Filed Date | 2002-12-12 |
United States Patent
Application |
20020185002 |
Kind Code |
A1 |
Herrmann, Michael |
December 12, 2002 |
Sliding ring for a radial piston pump, and device for the
installation thereof
Abstract
The sliding ring (1) for a radial piston pump has an inner ring
(2) and a coaxial outer ring (3) between which a spring/damping
element (5) is arranged. The spring/damping element (5) is in one
piece and comprises on both sides an annular rim bead (8). The rim
beads rest at the side rim of the inner ring (2) against the
latter's outer circumference and at the rim of the outer ring (3)
against the latter's inner circumference. Provided between the rim
beads (8) is a connecting structure (9) that is constituted, for
example, by at least one further damping ring (10) that is
connected via webs (11) to the rim beads (8). By way of a
corresponding configuration of the spring/damping element (5),
chambers (32) into which a liquid can be introduced can
additionally be formed between the inner ring (2) and outer ring
(3) so that the stiffness of the sliding ring (1) can be variably
configured.
Inventors: |
Herrmann, Michael; (Lebach,
DE) |
Correspondence
Address: |
DAVIS & BUJOLD, P.L.L.C.
500 NORTH COMMERCIAL STREET
FOURTH FLOOR
MANCHESTER
NH
03101
US
|
Family ID: |
7686527 |
Appl. No.: |
10/155635 |
Filed: |
May 23, 2002 |
Current U.S.
Class: |
92/129 ;
92/72 |
Current CPC
Class: |
F04B 53/22 20130101;
F04B 53/001 20130101; F04B 1/0413 20130101; F04B 9/045
20130101 |
Class at
Publication: |
92/129 ;
92/72 |
International
Class: |
F01B 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 30, 2001 |
DE |
101 26 151.9 |
Claims
1. A sliding ring (1) for a radial piston pump, having an inner
ring (2) and a coaxial outer ring (3) between which a
spring/damping element (5) is arranged, wherein the spring/damping
element (5) is in one piece and comprises on both sides a
respective annular rim bead (8) that rests at the side rim of the
inner ring (2) against the latter's outer circumference and at the
rim of the outer ring (3) against the latter's inner circumference;
and a connecting structure (9) is provided between the rim beads
(8).
2. The sliding ring as defined in claim 1, wherein the connecting
structure (9) comprises at least one further bead (10), resting
against the outer circumference of the inner ring (2) and the inner
circumference of the outer ring (3), that is connected to the rim
beads (8).
3. The sliding ring as defined in claim 1 or 2, wherein the sliding
ring (1) is substantially an arrangement made up of multiple
parallel beads (8,10) located next to one another and connected to
one another.
4. The sliding ring as defined in one of the foregoing claims,
wherein the beads (8,10) are connected to one another by webs
(11).
5. The sliding ring as defined in claim 4, wherein the webs (11)
extend substantially along the entire lateral circumference of the
beads (8,10).
6. The sliding ring as defined in claim 4, wherein the webs (11)
extend along only a portion of the lateral circumference of the
beads (8,10).
7. The sliding ring as defined in one of claims 4 through 6,
wherein the webs (11) are configured as preset breaking points that
break during operation of the sliding ring.
8. The sliding ring as defined in one of the foregoing claims,
wherein the beads (8,10) are damping rings having a circular cross
section.
9. The sliding ring as defined in one of claims 1 through 7,
wherein the beads (8,10) comprise a basic body and sealing lips,
continuous therewith, that rest against the outer ring (3) and/or
inner ring (2).
10. The sliding ring as defined in claim 1, wherein the rim beads
(8) rest in liquid-tight fashion against the inner ring (2) and
outer ring (3), and are connected to one another via transverse
webs (31) that rest against the inner ring (2) and/or outer ring
(3), so that along the outer circumference of the spring/damping
element (5) between the rim beads (8), a plurality of chambers (32)
separated by the transverse webs (31) are created between the inner
ring (2) and outer ring (3).
11. The damping ring as defined in claim 10, wherein the chambers
(32) each have at least one inflow opening (33,38) for a liquid;
and at least one of said inflow openings (33) is provided in the
circumferential wall of the inner ring (2).
12. The damping ring as defined in claim 10 or 11, wherein the
transverse webs (31) are equipped with passthrough openings (38) so
that each two adjacent chambers (32) are thereby connected.
13. The sliding ring as defined in claim 11 or 12, wherein the
inflow openings (33) in the wall of the inner ring (2) can be
connected to a liquid source.
14. The sliding ring as defined in one of claims 10 through 13,
wherein the transverse webs (31) are configured as bulkheads that
are arranged on the inner ring (2) and/or outer ring (3).
15. The sliding ring as defined in one of claims 10 through 14,
wherein the transverse webs can be retracted into and/or extended
out of the inner ring (2) and/or outer ring (3).
16. A device for placing an annular spring/damping element onto an
inner ring (2) of a sliding ring, the inner ring having on its side
rims circumferential shoulders (4) that hold the spring/damping
element (5) in place, characterized by the following features: a
cylindrical tube (22) that has an outside diameter approximately
corresponding to that of the inner ring (2) and onto which the
spring/damping element (5) can be slid; an installation taper (23)
that is continuous with the cylindrical tube (22), widens
conically, and can be placed onto a shoulder (4) of the inner ring
(2); a separate pusher tube (25) that can be slid flush onto the
cylindrical tube (22) and that at the end facing toward the
cylindrical tube (22) has a plurality of slots in the longitudinal
direction over at least a portion of its length over the entire
circumference, thus creating a plurality of leaves (27), separated
by slots (26), that can be elastically deflected and each have at
their front, free end a radially outwardly directed flange (28)
that can be brought into contact against the spring/damping element
(5) slid onto the cylindrical tube (22) and with which the
spring/damping element (5) can be slid, while spreading the leaves
(27), over the conical installation taper (23) onto the
circumference of the inner ring (2).
17. The device as defined in claim 16, wherein the diameter of the
cylindrical tube (22) is smaller than that of the inner ring
(2).
18. The device as defined in claim 16 or 17, wherein the pusher
tube (25) is equipped, at its end opposite the flange (28), with a
handle (29).
Description
[0001] The invention refers to a sliding ring for a radial piston
pump as defined in the preamble of claim 1, and to a device for the
installation thereof.
[0002] Sliding rings of this kind comprise an inner ring and a
coaxial outer ring, between which a spring/damping element is
arranged. The sliding ring fits around an eccentric and a sliding
bushing placed thereon, and acts with its external surface on
spring-braced pistons arranged in star-shaped fashion in a pump
housing, the piston chambers being connected to a consumption point
via outlet valves. Radial piston pumps of this kind are used, for
example, as fuel pumps in diesel trucks.
[0003] As existing art, reference may be made to DE-C2-43 36 673,
which describes a radial piston pump in which the sliding ring is
equipped with a spring/damping element, e.g., in the form of a
slotted spring washer, that can additionally be embedded in
plastic; this document also mentions the use, as the spring/damping
element, of a rubber ring vulcanized on either side onto the inner
ring and outer ring.
[0004] The operating noise of a radial piston pump can be reduced
by way of an elastic spring/damping element of this kind.
[0005] In order to reduce this noise further, it has been proposed
to arrange several rubber rings, e.g., conventional O-rings, next
to one another between the inner and outer ring. Usually three to
four O-rings are placed onto the inner ring between two lateral
shoulders. Both the manufacture and the installation of these
separate O-rings are relatively complex.
[0006] The spring/damping properties can be improved with these
known elements, but cannot be optimally adapted to the operation of
the sliding ring.
[0007] In addition, fundamental problems exist in radial piston
pumps having elastic sliding rings of this kind when taking in very
cold oil, e.g., at temperatures of about -20.degree. C. This has to
do with the increase in the oil's viscosity at lower temperatures,
and the associated greater difficulty in taking in said oil. In
order to improve the intake behavior of the radial piston pump, it
has therefore been proposed to lengthen the piston stroke in order
to give the oil more time to flow into the piston chamber. This is
made possible by a greater eccentricity of the pump eccentric, but
this action changes the volume flow characteristic curve of the
pump. This is not additionally prejudicial during the cold oil
intake phase--since what is most important then is that the pump
simply operate--but in normal operation such a change in the volume
flow characteristic curve cannot be accepted.
[0008] In the context of the aforementioned elastic sliding rings
having either several separate O-rings or other spring/damping
elements, it has been found that the elasticity of the sliding ring
causes a decrease in piston stroke and thus also volume flow. In
the operating phase during intake of cold oil, it would thus be
desirable to reduce the elasticity of the sliding ring and make it,
so to speak, harder. This is not possible, however, with the
aforementioned conventional sliding rings.
[0009] It is the object of the invention to describe a sliding ring
having a spring/damping element which is relatively simple to
manufacture and install; whose damping properties can be optimally
adapted, by way of the geometry of the spring/damping element, to
the particular function of the radial piston pump; and in which, by
way of a modification, the elasticity properties of the sliding
ring also can be modified, in particular the damping ring can be
set for harder elasticity, in order also to optimize the intake
behavior of the pump when the liquid to be taken in is at a low
temperature.
[0010] These objects are achieved, according to the invention, by
the features of claim 1.
[0011] The spring damping element accordingly is of one-piece
configuration and comprises on both circumferential sides a
respective annular bead that rests at the rim of the inner ring
against the latter's outer circumference and at the rim of the
outer ring against the latter's inner circumference, a connecting
structure being provided between said rim beads.
[0012] By means of the two rim beads, this basic structure of the
spring damping element forms, so to speak, the basis for numerous
modifications of the sliding ring, which can be adapted and
optimized for the particular function of the sliding ring and of
the radial piston pump by way of the connecting structure located
between the rim beads.
[0013] Since the spring damping element is in one piece, its
manufacture and of course its installation as well are less complex
than the manufacture and installation of multiple separate O-rings;
manufacture is also less complex than in the case of the
aforementioned composite designs.
[0014] Spring and damping properties as good as or even better than
with separate O-rings can be achieved if the connecting structure
comprises at least one further bead, resting against the outer
circumference of the inner ring and the inner circumference of the
outer ring, that is connected to the rim beads. The shape of the
spring/damping elements can preferably be selected in such a way
that said element is substantially an arrangement made up of
multiple parallel beads located next to one another, connected to
one another e.g., by webs.
[0015] The individual beads can have multifarious configurations in
a basic structure of this kind, for example can be circular or oval
in cross section. Also conceivable is a structure made up of a
basic body and sealing lips that protrude out from it on both sides
and rest against the inner and outer ring. This multifariously
modifiable geometry of the spring/damping element according to the
invention makes possible an optimization in terms of the function
of the sliding ring and of the respective radial piston pump.
[0016] The aforementioned webs for connecting the rim beads and
optional beads located therebetween extend substantially along the
entire lateral circumference of the beads, but can also extend only
along a portion of the lateral circumference. The latter
possibility, in particular, can advantageously be used if it should
be necessary to use individual beads or O-rings on the sliding
ring. In this case the webs between the beads can be configured as
preset breaking points that break during operation of the radial
piston pump. Since the spring/damping element is nevertheless
initially in one piece, the aforementioned advantages in the
context of manufacture and installation are retained.
[0017] By appropriate configuration of the connecting structure,
the elasticity of a sliding ring according to the invention can
also be made variable. For that purpose, provision is made for the
rim beads to rest in liquid-tight fashion against the inner and
outer ring, and to be connected to one another via transverse webs
that rest against the inner and/or outer ring, so that along the
outer circumference of the spring/damping element between the rim
beads, a plurality of chambers separated by the transverse webs are
created between the inner and outer ring. The individual chambers
each have at least one inflow opening for the liquid to be taken in
(e.g., oil), at least some of said inflow openings being provided
in the circumferential wall of the inner ring; when the pump is in
operation, they open into a groove of the eccentric through which
the chambers can be filled with liquid.
[0018] When at oil at low temperature needs to be taken in, the
elasticity of the sliding ring can thus be decreased by filling its
chambers, so that the piston stroke determined by the eccentricity
of the eccentric is no longer influenced, or is influenced to only
a small degree, by the elasticity of the sliding ring.
[0019] If no oil is introduced into the chambers of the sliding
ring, the sliding ring then functions as before as a spring/damping
element, with the deformation correspondingly adapted to the
operation of the radial piston pump and with the reduction in
piston stroke associated therewith. If the chambers are filled with
oil, however, there will not be much change if the oil is warm;
this change in function of course depends on the oil pressure,
since the relatively low-viscosity oil can escape very easily from
the orifices in the chambers. If the oil is cold and therefore
viscous, however, this can no longer occur so quickly because the
inflow openings are designed as throttle orifices, and the
elasticity of the sliding ring is thus reduced. The piston stroke
is thereby increased and the pump can deliver more volume, which
means better intake behavior with cold oil.
[0020] It is possible to modify the piston stroke, with no change
in the eccentricity of the eccentric, by specifically controlling
the oil pressure at which the chambers are filled and by allowing
oil to flow in controlled fashion into and out of the chambers. If
the oil pressure is increased, for example, the sliding ring
becomes stiffer, so that at maximum sliding ring stiffness the
piston stroke largely corresponds to the eccentricity of the
eccentric. Operating at low oil pressure, on the other hand, makes
the sliding ring softer, so that the piston stroke correspondingly
becomes less than the eccentricity of the eccentric. The volume
flow characteristic curve of the radial piston pump can, in this
fashion, be influenced during operation.
[0021] This kind of control of the volume flow can also be utilized
to improve pump functioning at high pump pressures. The reason is
that conventional radial piston pumps exhibit a sharp dip in volume
flow at high pump pressures, because the large forces acting on the
sliding ring at the high pump pressures deform it correspondingly
severely, and the piston stroke and thus also the volume flow of
the pump decrease accordingly.
[0022] With a controllable sliding ring according to the invention,
i.e., when the oil pressure in the chambers of the sliding ring and
the inflow and outflow of the oil present in the chambers are
controlled, the aforementioned effect can be counteracted. At a
high pump pressure the oil pressure in the sliding ring should thus
be elevated so that the sliding ring becomes stiffer and there is
little or no decrease in the piston stroke. The volume flow thus
remains the same even at high pump pressures.
[0023] According to a preferred embodiment of the invention, each
chamber of a controllable sliding ring of this kind is sealed off
in liquid-tight fashion with respect to the adjacent chambers, an
inflow opening through the wall of the inner ring then being
provided for each chamber.
[0024] Alternatively, it is possible to connect adjacent chambers
with one another through an opening; that opening extends, for
example, through the webs separating the chambers. It is also
possible to provide, in the outer circumference of the inner ring
or in the inner circumference of the outer ring, a groove by way of
which the chambers are then connected to one another. It would also
be possible to decrease the depth of the webs so that they no
longer rest against the inner and/or outer ring; as a result, a gap
remains there, through which oil can flow between the chambers.
With a design of this kind, an opening through the wall of the
inner ring does not need to be provided for each chamber; instead,
just a few inflow openings are sufficient here.
[0025] This kind of configuration of the sliding ring is
advantageous particularly for the intake of cold oil, since as a
result of the connection of the individual chambers, the oil can be
displaced internally in the sliding ring. The sliding ring thus
essentially retains its favorable damping properties. When the oil
is cold, the viscous oil can no longer distribute itself so easily
in the sliding ring, since it can no longer flow substantially
without significant resistance through the connections (configured
as throttles) between the chambers, resulting in an overall
stiffening of the sliding ring. The stiffness of the sliding ring
therefore depends on the viscosity of the oil and thus also on its
temperature.
[0026] If operation always occurs with a filled sliding ring, the
inflow openings through the wall of the inner ring essentially
serve to compensate for oil leakage and, if applicable, to control
the oil pressure in the sliding ring. In this context, it would be
conceivable to incorporate a check valve into the oil inlet, e.g.,
in a central conduit of the eccentric, so that oil can flow only
into the ring but not out of it. If the oil pressure in the sliding
ring is to be controlled, a modified valve must then of course be
provided in the delivery line.
[0027] In order to control the oil pressure in the sliding ring and
the oil flow between the individual chambers, it is conceivable to
provide webs, functioning as bulkheads, between the chambers, as a
result of which the sliding ring automatically becomes stiffer at a
higher oil viscosity. These bulkheads can be configured, for
example, as fixed webs on the inner and outer ring or, for example,
as movable webs that are mounted on the inner wall of the inner
ring and can be retracted and extended by means of a corresponding
oil flow between the individual chambers.
[0028] Further embodiments of the invention are evident from the
dependent claims. The invention is explained in further detail, in
several exemplary embodiments, with reference to the drawings in
which:
[0029] FIG. 1 is a side view of a sliding ring for a radial piston
pump with a spring/damping element according to the invention;
[0030] FIGS. 2 to 4 are sections through the sliding ring in 1
along line A-A, to explain different configurations of the
spring/damping element;
[0031] FIG. 5 is a plan view of a sliding ring having a
spring/damping element made up of three damping rings arranged next
to one another and connected to one another by webs;
[0032] FIG. 6 shows a partially sectioned device for installing a
spring/damping element on the inner ring of the sliding ring;
[0033] FIG. 7 is a sectioned depiction of a sliding ring with a
spring/damping element according to the invention whose elasticity
is adjustable;
[0034] FIG. 8 is a plan view of the spring/damping element of FIG.
7;
[0035] FIG. 9 shows a modified embodiment of a spring/damping
element according to the invention with adjustable stiffness;
[0036] FIG. 10 shows a further modified embodiment of a
spring/damping element according to the invention, indicating the
oil flow in the context of the forces of the eccentric and the
piston of the radial piston pump acting in opposite directions on
the upper side of the element; and
[0037] FIG. 11 shows the spring/damping element of FIG. 10,
indicating the oil flow in the context of the forces of the
eccentric and the piston of the radial piston pump acting in
opposite directions on the lower side of the element.
[0038] FIG. 1 depicts a sliding ring 1 for a radial piston pump 1
that has an inner ring 2 and an outer ring 3. The inner ring has on
both sides shoulders 4 that face toward the outer ring and hold a
spring/damping element 5 in place between the inner and outer ring.
Sliding ring 1 is slid in precisely fitting fashion onto an
eccentric 6 that rests flush against the inner circumference of
inner ring 2. The eccentric is driven by an eccentrically mounted
drive shaft 7. A sliding bushing (not depicted here) can also be
provided, if applicable, between eccentric 6 and inner ring 2.
[0039] As drive shaft 7 turns and eccentric 6 rotates,
spring-braced pistons arranged in star-shaped fashion in a housing
of the radial piston pump are displaced, so that oil is
correspondingly taken in and delivered to a consumption point.
Regarding function, the reader is referred to the aforementioned
German Patent DE-C2-43 36 673.
[0040] As shown in FIG. 2, spring/damping element 5 comprises two
elastic rim beads 8 that are configured, for example, as O-rings
and rest against the outer circumference of the inner ring and the
inner circumference of outer ring 3. The two rim beads 8 are
connected to one another via a connecting structure 9 that in this
case is constituted by a further damping ring 10 located in the
center of spring/damping element 5 and by webs 11 projecting out on
either side of said damping ring 10. Webs 11 thus each connect a
rim bead 8 to the central damping ring 10, so that a one-piece
spring/damping element 5 is present. Webs 11 extend around the
entire lateral circumference of beads 8 and damping ring 10.
[0041] In the present case, damping ring 10 also touches the outer
circumference of inner ring 2 and the inner circumference of outer
ring 3, so that the elastic properties of the spring/damping
element are determined substantially by the material properties of
all three rings and by the geometry of the spring/damping
element.
[0042] FIG. 3 depicts a spring/damping element that again comprises
two rim beads 8 and a central damping ring 10, which in this case
are identically configured and have a cross section in the form of
a square set on its vertices, resting with oppositely located
vertices against the outer circumference of inner ring 2 and the
inner circumference of outer ring 3. Beads 8 and damping ring 10
are once again connected to each other via webs 11, yielding a
one-piece spring/damping element.
[0043] Spring/damping element 5 shown in FIG. 4 again comprises two
rim beads 8 in the form of damping rings with an oval or circular
cross section, and a central damping ring 10 that in this case
takes the form of a rectangle and rests with the two narrow sides
of the rectangle against inner ring 2 and outer ring 3. Webs 11 are
once again provided in order to connect the individual rings.
[0044] FIG. 5 shows a spring/damping element 5 in plan view, the
upper half of outer ring 3 being omitted. This spring/damping
element comprises three damping rings arranged next to one another,
i.e., two rings 8 located at the rims and a central damping ring
10, which are connected to one another via small webs 11. Webs 11
are, for example, arranged at angular spacings of 90.degree. and
are configured such that upon operation of the radial piston pump,
these webs 11 act as preset breaking points. The spring/damping
element manufactured in one piece thus breaks apart, upon operation
of the pump, into three damping rings separated from and lying next
to one another.
[0045] FIG. 6 depicts a device 21 for installation of an annular
spring/damping element 5 as described above, i.e., for placing the
one-piece spring/damping element onto the outer circumference of
inner ring 2 between its shoulders 4. This device 21 comprises a
cylindrical tube 22 which has a diameter such that spring/damping
element 5 can easily be slid on. The diameter of this cylindrical
tube 22 is slightly smaller than the diameter of inner ring 2.
Continuous with this cylindrical tube is an installation taper 23
that widens conically and can be placed onto a shoulder 4 of inner
ring 2, and has at its enlarged end a thin circumferential flange
24 that is slid onto the outer circumference of a shoulder 4.
Device 21 furthermore has a separate pusher tube 25 that can be
mounted flush onto cylindrical tube 22. At its end facing toward
the cylindrical tube, the pusher tube has multiple slots in the
longitudinal direction over at least a portion of its length and
over the entire circumference, thus creating here a plurality of
leaves 27 separated by slots 26. These leaves 27 can be elastically
deflected and are each equipped at their front, free end with a
radially outwardly directed flange 28. At the opposite, closed end,
pusher tube 25 is equipped with a handle 29.
[0046] In order to install spring/damping element 5, the latter is
placed onto cylindrical tube 22; the pusher tube is then slipped
over the cylindrical tube until flange 28 is resting against the
back side of spring/damping element 5. The pusher tube is then
pushed toward the inner ring, thus pushing the spring/damping
element over installation taper 23 and elastically deflecting
leaves 27. As a result, the spring/damping element travels from the
first position (labeled A) on the cylindrical tube to the end of
installation taper 25, labeled as position B. As pusher tube 25 is
advanced further, spring/damping element 5 slides into the space
between shoulders 4 of inner ring 2. The entire device is then
pulled off shoulder 4 of inner ring 2.
[0047] FIG. 7 depicts a modified sliding ring 1. It too has an
inner ring 2 and an outer ring 3, between which is placed a
spring/damping element 5 that is held in place by shoulders 4 of
inner ring 2. The annular one-piece spring/damping element has two
rim beads 8 and a connecting structure 9 between the rim beads 8
that is constituted in this case by transverse webs 31.
[0048] Rim beads 8 are again made of elastic material, and rest in
liquid-tight fashion against the outer circumference of inner ring
2 and the inner circumference of outer ring 3. Transverse webs 31
also rest in more or less liquid-tight fashion in inner ring 2 and
on outer ring 3. The result is that a chamber 32 is formed between
each two webs. An inflow opening 33, penetrating through the wall
of inner ring 2 and configured as a throttle opening, is provided
for each chamber. Eccentric 6 has a central groove 34, running
around the entire circumference, that communicates with inflow
openings 33. Provided in drive shaft 7 is a central inflow orifice
35 at whose end a transverse orifice 36, which opens into groove 34
of the eccentric, branches off. A valve 37 (merely indicated here),
e.g., a check valve, can additionally be inserted into inflow
opening 25.
[0049] Inflow orifice 35 is connected to a source (not depicted
here) of a hydraulic fluid, e.g., oil. Each chamber 32 of the
sliding ring can thereby be filled with oil through inflow orifice
35, transverse orifice 36, groove 34, and inflow openings 33.
[0050] During normal operation of sliding ring 1, the latter can be
operated without oil in the individual chambers 32, so that the
elasticity and stiffness of sliding ring 1 are determined
substantially by the material properties and dimensions of
spring/damping element 5. If oil is introduced into chambers 32 and
held at a specific pressure, sliding ring 1 is thus made "stiffer,"
so that the elasticity of sliding ring 1 is determined additionally
or substantially by the oil pressure. As explained above, the
piston stroke of the individual pistons of the radial piston pump
can thereby be increased, which is advantageous in particular when
taking in cold oil.
[0051] FIG. 9 depicts a modification of the sliding ring shown in
FIGS. 7 and 8. The configuration of spring/damping element 5 is
similar to that in FIG. 8, but transverse webs 31 are each
penetrated by passthrough openings 38 that are configured as
throttle openings and each connect two adjacent chambers 32 to one
another. As a result, it is possible to provide only a smaller
number of inflow openings 33 in the wall of the inner ring; in the
example depicted, there are two inflow openings that once again
communicate with groove 34 in the eccentric (not depicted here).
This kind of configuration of the sliding ring allows the oil in
the respective chambers 32 to flow to adjacent chambers,
specifically from the region in which inner ring 2 lies close to
outer ring 3 into a region in which that distance is greater. A
modified sliding ring as shown in FIGS. 7 and 9 can also be slid
onto the inner ring using the installation device described
above.
[0052] In another embodiment of a sliding ring 1 according to the
present invention, it is proposed to arrange transverse webs 31 on
inner ring 2 and on outer ring 3 so that they act as bulkheads and
in that way influence the flow of oil in sliding ring 1. The
stiffness of sliding ring 1 is thereby increased, especially when
the oil's viscosity is higher. An embodiment of this kind, and its
manner of operation, are depicted in FIGS. 10 and 11, transverse
webs 31 between inner ring 2 and the outer ring being arranged
alternatingly on the inner ring and outer ring. Transverse webs 31
do not extend all the way to the respective opposite ring, so that
passthrough openings 38 are created here between adjacent chambers
32.
[0053] In FIG. 10, force K_e of the eccentric and force K_k of the
piston of the radial pump act in opposite directions on the upper
side of the spring/damping element. The sliding ring is then
compressed at the upper side so that oil is displaced there. The
indicated oil flow F then flows from the upper side in two opposite
directions toward the lower side of the sliding ring.
[0054] In FIG. 11, the two forces K_e and K_k act in opposite
directions on the lower side of sliding ring 1, so that it is
compressed there. The indicated oil flow F then flows from this
lower side in both directions toward the upper side of the sliding
ring.
[0055] As a further embodiment, provision can also be made to mount
these bulkheads movably, for example, in the inner ring, in such a
way that they are retracted and extended as a function of the oil
flow between the individual chambers.
[0056] In another embodiment, provision can also be made to
configure sliding ring 1, having transverse webs 31 acting as
bulkheads, as a sealed hydraulic damping element, i.e., without
inflow openings. This yields an additional degree of design
freedom, since the type of oil in the sealed sliding ring 1 is
independent of the type of oil in the pump. For example, silicone
oil can be used as the damping oil in the sealed sliding ring
1.
1 Reference characters 1 sliding ring 2 inner ring 3 outer ring 4
shoulder 5 spring/damping element 6 eccentric 7 drive shaft 8 rim
bead 9 connecting structure 10 damping ring 11 webs 21 installation
device 22 cylindrical tube 23 installation taper 24 flange 25
pusher tube 26 slots 27 leaves 28 flange 29 handle 31 transverse
webs 32 chambers 33 inflow openings 34 groove 35 inflow orifice 36
transverse orifice 37 valve 38 passthrough openings F oil flow in
sliding ring K_e force of eccentric K_k Force of piston
[0057]
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