U.S. patent application number 14/536420 was filed with the patent office on 2015-05-07 for hydrostatic axial piston machine.
The applicant listed for this patent is Robert Bosch GmbH. Invention is credited to Dieter Amesoeder, Lutz Bellmann, Michael Gaumnitz, Arnold Gente, Corinna Hager, Marcus Herrmann, Bernd Huehn, Andreas Illmann, Marian Kacmar, Tim Maier, Steffen Sies, Juergen Vdovak.
Application Number | 20150122115 14/536420 |
Document ID | / |
Family ID | 52829789 |
Filed Date | 2015-05-07 |
United States Patent
Application |
20150122115 |
Kind Code |
A1 |
Herrmann; Marcus ; et
al. |
May 7, 2015 |
Hydrostatic Axial Piston Machine
Abstract
A hydrostatic axial piston machine includes a drive shaft and a
plurality of cylinder sleeves in which a spherical or ball-shaped
section and a spherical or ball-shaped piston are inserted to
delimit a respective displacer chamber. The sections are secured on
a rotor, while the pistons are secured on a piston disk or piston
drum. The piston disk is configured to be tilted at different
pivoting angles relative to the rotor in a variable-displacement
machine, or the piston disk is tilted continuously relative to the
rotor in a constant-displacement machine. The rotor and the piston
disk are coupled to one another for conjoint rotation by a driving
device. The rotor and the piston disk can also be coupled
indirectly by a drive shaft of the machine. A sliding joint axial
with respect to a drive shaft is arranged between the rotor and the
piston disk.
Inventors: |
Herrmann; Marcus;
(Elchingen, DE) ; Bellmann; Lutz; (Ceske
Budejovice, CZ) ; Gente; Arnold; (Stuttgart, DE)
; Gaumnitz; Michael; (Horb, DE) ; Maier; Tim;
(Aichwald, DE) ; Amesoeder; Dieter; (Ludwigsburg,
DE) ; Illmann; Andreas; (Weil Der Stadt, DE) ;
Sies; Steffen; (Stuttgart, DE) ; Huehn; Bernd;
(Elchingen, DE) ; Hager; Corinna; (Stuttgart,
DE) ; Vdovak; Juergen; (Malmsheim, DE) ;
Kacmar; Marian; (Stuttgart, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Robert Bosch GmbH |
Stuttgart |
|
DE |
|
|
Family ID: |
52829789 |
Appl. No.: |
14/536420 |
Filed: |
November 7, 2014 |
Current U.S.
Class: |
92/12.2 |
Current CPC
Class: |
F04B 1/2035 20130101;
F01B 3/0035 20130101; F04B 1/124 20130101; F03C 1/0665 20130101;
F03C 1/0652 20130101; F04B 1/2071 20130101; F03C 1/0605
20130101 |
Class at
Publication: |
92/12.2 |
International
Class: |
F01B 3/00 20060101
F01B003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 7, 2013 |
DE |
10 2013 222 602.0 |
Claims
1. A hydrostatic axial piston machine, comprising: a drive shaft; a
rotor having a plurality of spherical or ball-shaped sections
arranged thereon; a piston disk having a plurality of pistons
arranged thereon, the piston disk being configured to be tilted
relative to the rotor or the rotor being configured to be tilted
relative to the piston disk; a plurality of cylinder sleeves with
each cylinder sleeve having a respective section of the rotor and a
respective piston of the piston disk inserted therein to define a
respective displacer chamber; and a driving device configured to
couple the piston disk and the rotor for conjoint rotation, wherein
an axial sliding joint is arranged between the rotor and the piston
disk.
2. The hydrostatic axial piston machine according to claim 1,
wherein the rotor is arranged perpendicularly to the drive shaft
and is one of connected to the drive shaft for conjoint rotation or
formed integrally therewith, and wherein the piston disk is
configured to be tilted relative to the drive shaft.
3. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has a joint having a transverse axis,
wherein two journals are arranged along the transverse axis, the
journals being inserted into two mutually opposite axial slotted
holes or grooves, or wherein a pin is arranged along the transverse
axis, the pin being inserted into two mutually opposite axial
slotted holes or grooves.
4. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has two joints having respective
transverse axes, and wherein the two transverse axes are set at 90
degrees to one another, and wherein two journals are arranged along
each transverse axis, the journals being inserted into two mutually
opposite axial slotted holes or grooves, or wherein a continuous
pin is arranged along each transverse axis, the pin being inserted
into two mutually opposite axial slotted holes or grooves.
5. The hydrostatic axial piston machine according to claim 3,
wherein laterally flattened sliding blocks are placed on end
sections of the journals or on the pin or pins, the sliding blocks
being pivotable about the transverse axis and being inserted into
the slotted holes or grooves in a sliding manner.
6. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has at least one Cardan joint, the
Cardan joint having a central part with two transverse axes, along
each of which two journals inserted into holes extend.
7. The hydrostatic axial piston machine according to claim 6,
wherein the central part is an intermediate sleeve arranged between
an outer circumference of the drive shaft or the rotor and an inner
circumference of the piston disk or an extension thereof.
8. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has a central bushing that is
articulated on the drive shaft or on the rotor and that is
articulated on the piston disk or an extension thereof.
9. The hydrostatic axial piston machine according to claim 8,
wherein the central bushing is articulated on the drive shaft or on
the rotor by two rotary-sliding connectors and is articulated on
the piston disk or an extension thereof by two rotary-sliding
connectors offset by 90 degrees relative to the rotary-sliding
connectors, wherein the rotary-sliding connectors each have a
sliding block that is guided in an axial slotted hole or an axial
groove, and wherein the rotary-sliding connectors each have a
journal that is inserted into a hole.
10. The hydrostatic axial piston machine according to claim 1,
wherein the driving device is formed by a plurality of radially
inward-directed projections, the radially inward-directed
projections each being arranged on a cylinder sleeve and being
configured to be engaged in axial grooves of the piston disk or of
an extension thereof.
11. The hydrostatic axial piston machine according to claim 1,
wherein the driving device is a constant velocity joint having a
plurality of balls, and wherein each ball is guided in a first
groove and a second groove.
12. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has at least two balls or spherical
segments that are each guided along a first track set obliquely to
the drive shaft and along a second track set obliquely to a
longitudinal axis of the piston disk.
13. The hydrostatic axial piston machine according to claim 12,
further comprising a pin extending along the first track.
14. The hydrostatic axial piston machine according to claim 12,
wherein each ball is guided along the first track and along the
second track by two grooves, respectively.
15. The hydrostatic axial piston machine according to claim 1,
wherein the driving device is a tripot joint having three spherical
segments, which are each guided so as to be movable on one of three
radial journals of the drive shaft or of the rotor, the radial
journals being distributed uniformly over the circumference, and
which are each guided so as to be movable in two axial grooves of
the piston disk.
16. The hydrostatic axial piston machine according to claim 1,
wherein the driving device is formed by the spherical or
ball-shaped sections and by the cylinder sleeves and by necks of
the pistons.
17. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has a plurality of recesses into which
corresponding pins are configured to be engaged.
18. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has a curved toothing on the drive shaft
or on the rotor and on the piston disk.
19. The hydrostatic axial piston machine according to claim 1,
wherein the driving device has a flexible element.
Description
[0001] This application claims priority under 35 U.S.C. .sctn.119
to patent application no. DE 10 2013 222 602.0, filed on Nov. 7,
2013 in Germany, the disclosure of which is incorporated herein by
reference in its entirety.
BACKGROUND
[0002] The disclosure relates to a hydrostatic axial piston
machine.
[0003] The known types of hydrostatic axial piston machines include
not only the classic type of machine with an integral rotating
cylinder drum but also a type of machine in which the cylinders are
arranged in revolving cylinder sleeves. The different displacer
chambers are therefore formed in individual cylinder sleeves, which
are articulated on a common rotor via respective ball joints, on
the one hand, and into which respective spherical or ball-shaped
pistons are inserted, on the other hand, said pistons being secured
on a common piston disk. By setting the piston disk obliquely to
the rotor or setting the rotor obliquely to the piston disk, the
desired stroke motion of the pistons in the cylinder sleeves is
produced as the cylinder sleeves revolve with the rotor and with
the piston disk. In this case, the rotor or the piston disk is
secured on a drive shaft or is formed integrally therewith, wherein
the drive shaft serves as an output shaft in the case of an axial
piston motor and as an input shaft in the case of an axial piston
pump. Axial piston machines of this kind require a driving device
in order to synchronize the rotary motion of the rotor and of the
piston disk despite the fact of their being set obliquely to one
another.
[0004] Printed publication DE 10 2007 011 441 A1 discloses a double
hydrostatic axial piston machine having two groups of individual
cylinder sleeves, in which toothing, a torsionally stiff bellows
and a constant velocity rolling bearing clutch are shown as a
driving device.
[0005] Printed publication DE 10 2012 222 850 A1 shows a
hydrostatic axial piston machine with individual cylinder sleeves,
wherein a driving pin inserted transversely into the drive shaft is
proposed as a driving device, said pin engaging in slots in a
collar on an obliquely set rotor disk. A Cardan joint and a
constant velocity joint are furthermore proposed as a driving
device.
[0006] In DE 10 2012 222 743 A1, a hydrostatic axial piston machine
is disclosed with individual cylinder sleeves, the obliquely set
cylinder end of which is articulated by means of a Cardan joint on
the drive shaft.
[0007] The disadvantage with hydrostatic axial piston machines of
this kind is that there is a rigid coupling between the rotor and
the piston disk in the direction of the drive shaft, and therefore
these components cannot be pushed apart by a mechanical force (e.g.
by a preloading spring).
[0008] Given this situation, it is the underlying object of the
disclosure to provide a hydrostatic axial piston machine having
individual cylinder sleeves, in which this disadvantage is
eliminated.
SUMMARY
[0009] The object is achieved by a hydrostatic axial piston machine
having the features of the disclosure.
[0010] The hydrostatic axial piston machine has a drive shaft and a
plurality of cylinder sleeves, in which a spherical or ball-shaped
section, on the one hand, and a spherical or ball-shaped piston, on
the other hand, are inserted in order to delimit a respective
displacer chamber. The sections are secured on a rotor, while the
pistons are secured on a piston disk or piston drum. Depending on
the embodiment, the piston disk and the rotor can be tilted
relative to one another in a variable-displacement machine, or the
piston disk and the rotor are tilted relative to one another in a
constant-displacement machine. The rotor and the piston disk are
furthermore coupled to one another for conjoint rotation by means
of a driving device. This coupling can also be implemented
indirectly by means of a drive shaft of the machine. According to
the disclosure, a sliding joint axial with respect to a drive shaft
is arranged between the rotor and the piston disk. This ensures
decoupling and axial mobility of the piston disk relative to the
rotor.
[0011] The axial sliding joint can have a key and a groove or
toothing, for example.
[0012] The driving device can be arranged inside or outside a pitch
circle of the sections and pistons. At the outer circumference of
the pitch circle, the circumferential forces to be transmitted are
lower, and therefore the driving device can have comparatively
small individual elements (e.g. journals). In this case, the drive
shaft can be continuous.
[0013] To support an axial preloading force, which is required
between the piston disk and the rotor, a pressure sleeve can be
arranged on (e.g. pushed onto) the outer circumference of the drive
shaft, said sleeve having on its outer circumference a spherical
shape against which the piston disk or the rotor rests.
[0014] In a preferred principle of the axial piston machine
according to the disclosure, the rotor is arranged perpendicularly
to the drive shaft and is connected to the latter for conjoint
rotation or is formed integrally therewith, while the piston disk
can be tilted or is tilted relative to the drive shaft.
[0015] The piston disk can be provided with a bushing-type
extension, which is part of the driving device or which is used to
articulate the driving device thereon.
[0016] In an illustrative embodiment which is simple in terms of
device design, the driving device has a joint having just one
transverse axis. According to a first variant, two journals are
arranged along the transverse axis, said journals being inserted
into two mutually opposite axial slotted holes or grooves in such a
way as to be pivotable and slidable. According to a second variant,
a continuous pin is arranged along the transverse axis, said pin
being inserted into two mutually opposite axial slotted holes or
grooves in such a way as to be pivotable and slidable.
[0017] In a Cardan-like illustrative embodiment, the driving device
has two joints having respective transverse axes, wherein the two
transverse axes are set at 90 degrees to one another. According to
a first variant, two journals are in this case arranged along each
transverse axis, said journals being inserted into two mutually
opposite axial slotted holes or grooves in such a way as to be
pivotable and slidable. In this case, the two transverse axes can
intersect, i.e. form a cross. According to a second variant, a
continuous pin is arranged along each transverse axis, said pin
being inserted into two mutually opposite axial slotted holes or
grooves.
[0018] To reduce frictional losses, laterally flattened sliding
blocks or sliding bushings can be placed on end sections of the two
or four journals or on the pin or pins, said sliding blocks being
pivotable or rotatable relative to the journal or to the pin or
pins about the transverse axis and being inserted in a sliding
manner into the slotted holes or grooves.
[0019] In another illustrative embodiment, the driving device has
at least one Cardan joint known per se from the prior art, the
central part of which has two transverse axes, which intersect and
are perpendicular to one another and along each of which two
journals inserted pivotably into holes extend.
[0020] In a development of the Cardan joint, the central part
thereof can be an intermediate sleeve which is annular, for
example, which is arranged between an outer circumference of the
drive shaft of or the rotor and an inner circumference of the
piston disk or the bushing-type extension thereof. In this case,
the intermediate sleeve can be connected in an articulated manner
to the rotor by means of two mutually opposite inner journals and
can be connected in an articulated manner to the piston disk by
means of two mutually opposite outer journals, for example.
[0021] Particularly in the case of relatively large tilting angles
of the piston disk, it is preferred if the driving device has a
central bushing, which, on the one hand, is articulated on the
drive shaft or on the rotor and, on the other hand, is articulated
on the piston disk or the bushing-type extension thereof. This
enables the central bushing to adopt a tilt relative to the drive
shaft corresponding to half the tilt of the piston disk.
[0022] In this arrangement, the two articulations can be embodied
by respective Cardan joints with intermediate sleeves as described
above, for example.
[0023] The central bushing can also be articulated on the drive
shaft or on the rotor by means of two rotary-sliding connectors and
can be articulated on the piston disk or the extension thereof by
means of two rotary-sliding connectors offset by 90 degrees
relative to said rotary-sliding connectors. The rotary-sliding
connectors each have a sliding block which is guided in an axial
slotted hole or an axial groove, and they each have a journal which
is inserted pivotably into a hole.
[0024] In another preferred illustrative embodiment, the driving
device is formed by a plurality of radially inward-directed
projections, e.g. webs, which are each arranged on a cylinder
sleeve and which remain engaged in axial grooves of the piston disk
or of the extension thereof during revolution or can be engaged
therein during revolution in order in this way to transmit the
torque. In this illustrative embodiment, no additional components
are required for the driving device.
[0025] In another preferred illustrative embodiment, the driving
device has a constant velocity joint or homokinetic joint, which
has a plurality of balls, wherein each ball is guided in a first
and a second groove.
[0026] In this case, the balls can be guided in a cage, thereby
making possible pairs of grooves which are not capable alone of
determining the position of the common ball thereof.
[0027] In another preferred illustrative embodiment, the driving
device has at least two balls or spherical segments distributed
over the circumference, which are each guided along a first
straight track set obliquely to the drive shaft (or to the rotor)
and along a second straight track set obliquely to a longitudinal
axis of the piston disk. In an embodiment as a bipot joint, two
mutually opposite balls or spherical segments are provided.
[0028] In this case, a pin can be provided, which extends along the
first track. According to a first variant, the ball or spherical
segment is secured on the pin, and the pin can be moved along the
first track. According to a second variant, the pin is secured on
the drive shaft or on the rotor, while the ball or spherical
segment can be moved along the pin and hence along the first
track.
[0029] As an alternative, it is also possible for each ball to be
guided along the first track and along the second track by two
grooves in each case.
[0030] The driving device can be a tripot joint having three
spherical segments, which are each guided so as to be movable on
one of three radial journals of the drive shaft or of the rotor,
said radial journals being distributed uniformly over the
circumference, and which are each guided so as to be movable in two
mutually opposite axial grooves of the piston disk.
[0031] It is also possible to provide two tripot joints of this
kind, of which a first tripot joint connects the drive shaft or the
rotor in an articulated manner to the central bushing, and wherein
the second tripot joint connects the central bushing in an
articulated manner to the piston disk.
[0032] In another preferred illustrative embodiment which is simple
in terms of device design, the driving device is formed by the
spherical or ball-shaped sections inserted in the cylinder sleeves
and by the cylinder sleeves and by necks of the pistons. The necks
are preferably of tapered shape for this purpose.
[0033] In another illustrative embodiment, the driving device has a
plurality of recesses, which are distributed over the circumference
of the rotor, for example, and into which corresponding pins, which
are secured on the piston disk, for example, engage during
revolution.
[0034] In another illustrative embodiment, the driving device has a
curved toothing, which is formed on the drive shaft or on the
rotor, on the one hand, and on the piston disk, on the other hand.
In the case of a constant-displacement machine, the toothing can be
of tapered configuration.
[0035] The driving device can also have a flexible element or an
element which can be bent according to the tilt of the drum disk.
This element can be a bellows, for example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Various illustrative embodiments of a hydrostatic axial
piston machine according to the disclosure are described in detail
below with reference to the figures.
[0037] In the drawings:
[0038] FIG. 1 shows essential parts of a first illustrative
embodiment in a schematic longitudinal section,
[0039] FIG. 2 shows a detail of a second illustrative embodiment in
a transparent perspective view,
[0040] FIG. 3 shows a detail of a third illustrative embodiment in
a longitudinal section,
[0041] FIG. 4 shows a detail of a fourth illustrative embodiment in
a longitudinal section,
[0042] FIG. 5 shows a detail of a fifth illustrative embodiment in
a longitudinal section,
[0043] FIG. 6 shows a detail of a sixth illustrative embodiment in
a longitudinal section,
[0044] FIG. 7 shows a detail of a seventh illustrative embodiment
in a transparent perspective view,
[0045] FIG. 8 shows a detail of an eighth illustrative embodiment
in a perspective view,
[0046] FIG. 9 shows a detail of a ninth illustrative embodiment in
a longitudinal section,
[0047] FIG. 10 shows essential parts of a tenth illustrative
embodiment in a longitudinal section,
[0048] FIG. 11 shows a detail of an eleventh illustrative
embodiment in a transparent perspective view,
[0049] FIG. 12 shows a detail of a twelfth illustrative embodiment
in a transparent perspective view,
[0050] FIG. 13 shows a detail of a thirteenth illustrative
embodiment in a transparent perspective view, and
[0051] FIG. 14 shows a detail of a fourteenth illustrative
embodiment in a perspective view.
DETAILED DESCRIPTION
[0052] FIG. 1 shows the essential parts of a first illustrative
embodiment of a hydrostatic axial piston machine according to the
disclosure. It has a drive shaft 1, to which a disk-shaped rotor 2
is coupled for conjoint rotation. Uniformly distributed spherical
segments 4 are secured on the circumference thereof, onto each of
which segments a cylinder sleeve 6 is pushed in such a way that
they jointly form a ball joint. A spherical piston 8 is furthermore
inserted into each cylinder sleeve 6, with the result that the
spherical segment 4 delimits a displacer chamber 10 together with
the piston 8. Each piston 8 is secured by means of a neck 12 on a
piston disk 14, which is set at an angle to the rotor 2 and hence
to the drive shaft 1.
[0053] During revolution of the drive shaft 1 with the rotor 2, the
piston disk 14 and with the cylinder sleeves 6, the pistons 8
perform a stroke motion relative to the respective cylinder sleeve
6. In this case, the spherical pistons 8 are inserted pivotably in
the respective cylinder sleeves 6. The piston disk 14 is pushed in
the direction of the rotor 2 (to the left in FIG. 1) against an
annular pressure sleeve 15, which is mounted on the drive shaft 1
and is supported there on a radial shoulder (not shown).
[0054] By means of an axial sliding joint according to the
disclosure, which is designed as a groove-key arrangement 16
between the rotor 2 and the drive shaft 1 in the first illustrative
embodiment according to FIG. 1, the axial decoupling of the rotor 2
from the piston disk 14 is achieved.
[0055] Driving is accomplished by means of the displacer unit
having the three contact partners: spherical segment 4, cylinder
sleeve 6 and neck 12. In this case, the necks 12 are configured in
such a way that, at one of the pistons 8, there is always surface
contact between the neck 12 thereof and the associated cylinder
sleeve 6, via which the torque is transmitted. The driving piston 8
changes during one revolution of the illustrative embodiment shown
in FIG. 1.
[0056] FIG. 2 shows a detail of a second illustrative embodiment of
the axial piston machine according to the disclosure in a
transparent perspective view. The rotor (not shown in FIG. 2) is
supported on the drive shaft 1 by means of toothing 116. The piston
disk 114 is developed to give a piston drum, which has a
bushing-type extension 120. Two mutually opposite slotted holes 122
are introduced into said extension. A pin 124 is inserted
transversely into the drive shaft 1, respective sliding blocks 126
being secured rotatably on each of the end sections of said pin
which project from the drive shaft 1. The sliding blocks 126 are
secured on the pin 124 by means of wire rings 128.
[0057] The piston disk 114 is driven by means of flattened outer
regions of the sliding blocks 126, which are in contact with one of
two contact surfaces of the slotted holes 122. As an alternative,
the pin can also be secured in the rotor instead of in the drive
shaft. Moreover, the pin can be introduced into the piston disk or
into the extension and the contact surfaces can be introduced into
the rotor. As a supplement to the second illustrative embodiment
according to FIG. 2, it is also possible for two pins 124 with a
total of four sliding blocks 126 to be provided, wherein the two
pins 124 are arranged crosswise relative to one another. To
transmit the axial preloading force, there is furthermore a need
for a spherical cap, which is positioned between the pressure
sleeve 15 and the piston disk 114, for example.
[0058] FIG. 3 shows a third illustrative embodiment according to
the principle of a Cardan joint, wherein only a short section of
the drive shaft 1 and only an end section of the extension 120 of
the piston disk 114 are shown. A sleeve-shaped section of the rotor
102 is shown on the drive shaft 1. An annular intermediate sleeve
130 is provided between said section and the extension 120. With
the rotor 102, this forms a first axis of rotation (situated in the
plane of the drawing) and, with the extension 120, it forms a
second axis of rotation perpendicular thereto (arranged
perpendicularly to the plane of the drawing). For this purpose,
four pins (not shown in FIG. 3) are provided, being inserted into
corresponding holes.
[0059] FIG. 4 shows a fourth illustrative embodiment, in which two
Cardan joints based on the principle of the illustrative embodiment
shown in FIG. 3 and also a central bushing 132 associated therewith
are provided. The two intermediate sleeves 130 are pinned to the
central bushing 132 perpendicularly to the plane of the drawing,
thus allowing rotation about the pin axis. A similar rotary
connection, which is perpendicular thereto in each case, is
established between the rotor 102 and one intermediate sleeve 130
and between the piston disk 114 and the other intermediate sleeve
130.
[0060] In the third illustrative embodiment and in the fourth
illustrative embodiment, axial decoupling is ensured by introducing
a groove-key arrangement 16 according to FIG. 1.
[0061] FIG. 5 shows a fifth illustrative embodiment, in which the
driving device is formed by a ball-type constant velocity joint.
This has a plurality of balls 234, which are guided in straight
axial ball races. To be more precise, each ball 234 has a first
groove 236 formed in the rotor 202 and a second groove 237 formed
in the extension 220 of the piston disk. All the grooves 236, 237
extend axially with respect to the respective component 202, 220,
in which they are arranged. As an alternative to the grooves 236,
237 shown in FIG. 5, said grooves can also be curved.
[0062] Since the shape of the grooves 236, 237 does not
unambiguously determine the position of the associated balls 234 in
the fifth illustrative embodiment according to FIG. 5, a cage 238
is used for definite guidance of the balls 234. The cage 238 is
configured in such a way that the rotation of the rotor 202 and of
the piston disk take place synchronously. The pressure sleeve 15 is
provided for transmission of the axial force, being clamped between
the rotor 202 and the cage 238.
[0063] According to another basic variant, the driving device is
formed by a plurality of pots, the balls 244 of which each run on
two obliquely set straight tracks.
[0064] FIG. 6 shows an illustrative embodiment in which a plurality
of spherical segments 240 are guided in such a way as to be movable
along a respective pin 241 secured on the rotor 202 and set
obliquely to the latter. Each spherical segment 240 is furthermore
guided along a track 242 set obliquely to a longitudinal axis of
the piston disk 214. As an alternative, the spherical segment can
be secured on the pin, which is then supported in an axially
movable manner in the rotor. The rotor and the piston disk can
furthermore be exchanged.
[0065] FIG. 7 shows a seventh illustrative embodiment, in which a
ball 244 is, on the one hand, guided along a track set obliquely to
the longitudinal axis of the rotor 202 by means of two mutually
opposite grooves 245. On the other hand, the ball 244 is guided
along the track set obliquely to the longitudinal axis of the
piston disk 214, likewise by means of two mutually opposite grooves
246. The pairs of grooves 245, 246 are formed in respective pairs
of guide rails, which are inserted into the rotor 202 and into the
piston disk 214. A pressure sleeve 15 (not shown in FIG. 7) is used
to transmit the axial force. The axial sliding joint is formed by
the toothing 116.
[0066] FIG. 8 shows an eighth illustrative embodiment, in which the
driving device is designed as a tripot joint. In this case, three
radial journals 248 uniformly distributed over the circumference
are secured on the rotor 202, on each of which a spherical segment
240, e.g. an annular spherical segment, is rotatably supported. The
extension 220 of the piston disk 214 has three axial slotted holes,
in which pairs of mutually facing grooves 245, 246, 247 are
arranged. These pairs of grooves 245, 246, 247 each guide one
spherical segment 240. A pressure sleeve 15 (not shown in FIG. 8)
is used to transmit the axial force. It is also possible to provide
a double tripot joint between the drive shaft 1 and the piston disk
214 or the extension 220 thereof, said joint consisting of two
tripot joints according to FIG. 8.
[0067] FIG. 9 shows a detail of a ninth example, in which the
driving device between the rotor 202 and the extension 220 of the
piston disk has two or more pins 250, which extended radially
inward from the inner circumference of the extension 220. The pins
250 project into corresponding recesses 252 in the rotor 202.
Driving is in each case accomplished by means of those pins 250
which are in contact with the rotor 202. As an alternative, it is
also possible for the pins to be provided in the rotor and for the
recesses to be provided in the piston drum or in the extension
thereof. The axial forces are transmitted by a separate component
similar to the pressure sleeve 15 from FIG. 2.
[0068] FIG. 10 shows a tenth illustrative embodiment of the axial
piston machine according to the disclosure. The rotor 302 thereof
is connected for conjoint rotation to the drive shaft 1 by means of
the toothing 116. Circular-cylindrical necks 312, on which the
pistons 8 are formed, are inserted into the piston disk 314, which
is tilted relative to said shaft. Between the rotor 302 and the
piston disk 314 there are two individual Cardan joints. The
intermediate sleeves 330 thereof are both pinned to a central
bushing 332, allowing rotation about the pin axis. A similar rotary
connection is established between the rotor 302 and the associated
intermediate sleeve 330 and between the piston disk 314 and the
associated intermediate sleeve 330. The axial preloading force can
be transmitted by means of a spring (not shown) between an axially
movable component 354 and the piston disk 314, for example.
[0069] FIG. 11 shows a detail of an eleventh illustrative
embodiment having a driving device, in which a sleeve-type
extension of the rotor 302 engages around an extension 220 of the
piston disk. An individual Cardan joint having two joint
connections is situated between them. On the one hand, there is a
rotary-sliding connection with two partners and a rotary-sliding
connection offset by 90.degree. thereto in the direction of
rotation, likewise with two partners. FIG. 11 shows a solution by
means of four flattened pins 356, wherein a main section of a
journal 356 and a foot section of another journal 356 are shown in
FIG. 11. Each journal 356 is guided on one side in a bore and on
the other side in a slotted hole 122. To transmit the axial
preloading force, there is furthermore a need for a spherical cap,
which is positioned between the drive shaft and the piston drum,
for example.
[0070] In the illustrative embodiment according to FIG. 12, two
individual Cardan joints according to FIG. 11 and a central bushing
432 are provided as a driving device. The uniform torque
transmission of the rotor 402 to the piston drum, of which only the
extension 220 is shown in FIG. 12, is ensured by the fact that a
central axis of the central bushing 432 assumes the same angle in
each case to the axis of the rotor 402, on the one hand, and to the
axis of the extension 220 and hence of the piston disk, on the
other hand.
[0071] FIG. 13 shows a thirteenth illustrative embodiment, in which
the driving device is formed by a double Cardan of compact
construction. Between the rotor 402 and the extension 220 of the
piston disk there is a central bushing 532, which is connected to
the rotor 402 by means of two rotary-sliding connectors 558, on the
one hand, and to the extension 220 by means of rotary-sliding
connectors 558 arranged offset by 90.degree. thereto, on the other
hand. Each rotary-sliding connector 558 has a journal, by means of
which it is inserted into a corresponding hole, and a sliding
block, which is inserted into a corresponding slotted hole 122.
This arrangement makes it possible to introduce the slotted holes
122 in the central bushing 532 offset by 90.degree. relative to the
holes, enabling the central bushing 532 to be of compact
configuration without sacrificing rigidity. The angular position of
the central bushing 532 and hence the uniform torque transmission
and the transmission of the axial preloading force are ensured as
in the twelfth illustrative embodiment according to FIG. 12.
[0072] FIG. 14 shows a fourteenth illustrative embodiment of the
axial piston machine according to the disclosure, wherein only one
cylinder sleeve 606 is shown between the piston disk 314 and the
rotor 402 for the sake of clarity. On its side facing the extension
620 of the piston disk 314, each cylinder sleeve 606 has a radially
inward-directed projection 660, which extends approximately along
the cylinder sleeve 606. Corresponding axial grooves 662 are
introduced on the outer circumference of the extension 620, wherein
the projection 660 of the associated cylinder sleeve 606 engages in
the groove 662, depending on its rotational position. In this case,
the driving device is formed by the projections 660 and the grooves
662 without the need to provide special components for driving.
[0073] A disclosure is made of a hydrostatic axial piston machine
having a drive shaft and having a plurality of cylinder sleeves, in
which a spherical or ball-shaped section, on the one hand, and a
spherical or ball-shaped piston, on the other hand, are inserted in
order to delimit a respective displacer chamber. The sections are
secured on a rotor, while the pistons are secured on a piston disk
or piston drum. Depending on the embodiment, the piston disk can be
tilted at different pivoting angles relative to the rotor in a
variable-displacement machine, or the piston disk is tilted
continuously relative to the rotor in a constant-displacement
machine. The rotor and the piston disk are coupled to one another
for conjoint rotation by means of a driving device. This coupling
can also be implemented indirectly by means of a drive shaft of the
machine. A sliding joint axial with respect to a drive shaft is
arranged between the rotor and the piston disk.
LIST OF REFERENCE SIGNS
[0074] 1 drive shaft [0075] 2; 102; 202; 302; 402 rotor [0076] 4
spherical segment [0077] 6; 606 cylinder sleeve [0078] 8 spherical
piston [0079] 10 displacer chamber [0080] 12; 312 neck [0081] 14;
114; 214; 314 piston disk [0082] 15 pressure sleeve [0083] 16
groove-key arrangement [0084] 116 toothing [0085] 120; 220; 620
extension [0086] 122 slotted hole [0087] 124 pin [0088] 126 sliding
block [0089] 128 wire ring [0090] 130; 330 intermediate sleeve
[0091] 132; 332; 432; 532 central bushing [0092] 234 ball [0093]
236 first groove [0094] 237 second groove [0095] 238 cage [0096]
240 spherical segment [0097] 241 pin [0098] 242 track [0099] 244
ball [0100] 245, 246, 247 groove [0101] 248 radial journal [0102]
250 pin [0103] 252 recess [0104] 354 axially movable component
[0105] 356 journal [0106] 558 rotary-sliding connector [0107] 660
projection [0108] 662 groove
* * * * *