EP0367046B1 - Hydrostatic rotary piston machine - Google Patents

Hydrostatic rotary piston machine Download PDF

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Publication number
EP0367046B1
EP0367046B1 EP19890119514 EP89119514A EP0367046B1 EP 0367046 B1 EP0367046 B1 EP 0367046B1 EP 19890119514 EP19890119514 EP 19890119514 EP 89119514 A EP89119514 A EP 89119514A EP 0367046 B1 EP0367046 B1 EP 0367046B1
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EP
European Patent Office
Prior art keywords
tooth
rotary piston
teeth
rotary
piston machine
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19890119514
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German (de)
French (fr)
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EP0367046A1 (en
Inventor
Siegfried Dipl.-Ing. Eisenmann
Hermann Härle
Original Assignee
Eisenmann, Siegfried A., Dipl.-Ing.
Hermann Härle
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Publication date
Priority to CH3943/88 priority Critical
Priority to CH394388A priority patent/CH679062A5/de
Application filed by Eisenmann, Siegfried A., Dipl.-Ing., Hermann Härle filed Critical Eisenmann, Siegfried A., Dipl.-Ing.
Publication of EP0367046A1 publication Critical patent/EP0367046A1/en
Application granted granted Critical
Publication of EP0367046B1 publication Critical patent/EP0367046B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00Rotary-piston machines or pumps
    • F04C2/08Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/10Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member
    • F04C2/103Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member one member having simultaneously a rotational movement about its own axis and an orbital movement

Description

  • The invention relates to a hydrostatic rotary piston machine of the type specified in the preamble of claim 1. These hydrostatic machines can be used both as a hydraulic pump, but preferably as a hydraulic motor, and are particularly popular as slow-running "torque motors". Liquids and gases are understood as working fluids. Their main advantage is a relatively large swallowing volume per revolution and thus a relatively high output torque. Designs according to the generic term have the advantage that the shaft to the left and right of the displacer part and the control part can be stored in large-sized roller bearings, so that not only is there a shaft bearing that is precise for the hydraulic part, but also a large bearing distance is realized, which is based on the type - or output shaft end - due to the large leverage effect of the shaft - allows large radial forces. This makes it possible not only to allow large belt and tooth forces for torque introduction and dissipation in these machines, but these machines can also be used as drive hubs for hydrostatic wheel drives.
  • A known machine of this type (DE-A-1.703.573) has a so-called gerotor toothing between the fixed housing and the outer toothing of the rotary piston. This toothing works there as a displacement part. The circular piston also has gerotor teeth in its inner area, its inner rotor being connected in one piece to the input or output shaft in a rotationally fixed manner. In this machine, attempts are made to ensure the supply and disposal of the positive toothing via control slots which are arranged on the rotary piston itself. For design and gear kinematic reasons, it is necessary that the eccentricities of both gerotor gears must be the same. Thus, the tooth height of the positive toothing depends on the tooth height of the much smaller toothing on the shaft, so that the conveying surface, that is specific volume per revolution of the positive toothing is still relatively small. The flow cross sections that can be achieved by the commutator control provided there are also unfavorable, so that high throttle losses occur.
  • Rotary piston machines have also become known which have generic differences, for example US Pat. No. 3,288,078, which shows an output shaft mounted on one side. Such solutions are ruled out for high power transmissions, since the shaft in question or its bearings, in particular the relatively fine toothing between the rotor and drive shaft, is hardly suitable for transmitting sufficient forces. From US-A-3,658,449 a hydrostatic rotary piston machine has become known, which also dispenses with a double-sided central shaft and instead has a driving wobble shaft with a numbered wave profile as the force transmission member. Such arrangements have the disadvantage that they have to be small in diameter, and therefore can only transmit relatively small forces and are subject to high wear, especially since the tooth profiles of the wobble shaft are only partially in engagement with the opposing tooth profiles.
  • The invention has for its object to provide a hydrostatic rotary piston machine of the type specified, in which the disadvantages mentioned above do not occur. In particular, the swallowing volume is to be increased and a hydrostatic rotary piston machine is proposed in which as many parts as possible can be produced using highly efficient processes, e.g. in the sintering process. The number of parts required should also be as small as possible. The axially moldable parts, e.g. the control housing 38. This is achieved according to the invention by the combination of the features of claim 1.
  • Appropriate embodiments are defined by the features of the subclaims.
  • According to the invention, namely in the displacement toothing, which is referred to below as the first inner or outer toothing, with a tooth number difference of 1, double the tooth height is obtained if the toothing provided between the rotary piston and the shaft, which is referred to as the second inner and external toothing, has a higher difference in the number of teeth than 1. This much larger swallowing volume of the displacement toothing, however, requires time-consuming control (in cm2 / sec) of the inflow and outflow for the working medium, which is why a separate rotary commutator must be provided. Since the rotary piston transfers its torque to the shaft via very large tooth forces, this shaft must be made very stable. Since this thick shaft must be passed through the rotary commutator, a new path must be taken to drive it through the rotary piston. This should also be the reason why the professional world has so far not considered a higher number of teeth difference than possible.
  • This object is now achieved in an extremely advantageous manner in that the second internal and external toothing has a difference in the number of teeth of at least 2, and in that the rotary commutator of the control part is coupled to the rotary piston via a circular gear with a transmission ratio of 1: 1. The rotary commutator can be freely rotated in relation to the shaft.
  • As a possible tooth shape between the rotary piston and the shaft, an internal toothing with concave tooth flanks is suitable, which have a circular arc shape and determine the shape of the tooth flanks of the second external toothing on the input or output shaft by rolling on the second internal toothing of the rotary piston. Such internal teeth have particularly small sliding components, due to a very small pressure angle.
  • The efficiency of the internal gear between the rotary piston and the shaft can be further improved by the second internal toothing (of the rotary piston) having convexly circular tooth flanks, the shape of the tooth flanks of the second external toothing (the shaft) being determined by rolling on the second internal toothing and thus has a concave tooth shape. As a result, the notch-free cross-section of the rotary lobe is also larger than in the variant with concave flanks on the second internal toothing, which results in greater stability or a narrower design.
  • A perfect rotary commutator control for the supply and disposal of the displacement part has the condition, as is generally known in such machines, that the rotary commutator executes exactly the same speed as the rotary piston around its own axis. Since the rotary piston does not 'only perform a rotary movement, but also an eccentric movement, this 1: 1 ratio causes constructional difficulties. In the rotary piston machine according to the invention, this becomes 1: 1 ratio achieved in that the rotary commutator has gear extensions directed towards the displacement part, which mesh directly with the second internal toothing of the rotary piston. The 1: 1 ratio arises from the fact that between the rotary commutator and the rotary piston there is a circular gear with the ratio 1: 1, in which the gear extensions protruding from the rotary commutator are designed as teeth with circular tooth flanks - evenly distributed along a circumference of the partial circle - and in circular arcs Engage the teeth of the rotary piston as a second internal toothing, the radius of which is smaller by the eccentricity of the rotary piston machine than the radius of the circular tooth flanks of the gear extensions or vice versa. High performance is not transferred.
  • Conversely, the teeth between the rotary piston and the output shaft must be designed as rolling teeth with the smallest sliding components to minimize losses. However, since the rotary commutator works practically torque-free, a gear with a relatively high proportion of sliding can be used to drive it, as is the case with the circular-arc gear. For example, a coupling can be provided as in the cyclo transmission. Within the scope of the invention, the content of the CH patent application "circular arc transmission" from the same filing date is also disclosed. When the second internal toothing is designed with concave teeth, the 1: 1 drive of the rotary commutator is provided by the fact that the gear extensions of the rotary commutator, which are evenly distributed over the circumference, protrude directly into the second internal toothing of the rotary piston with concave circular tooth flanks and the number of extensions is the same is the number of teeth of the second internal toothing, the shape of the extensions being determined according to the guidelines for a circular arc transmission according to claim 7 and having convex tooth flanks. A sufficient degree of coverage can be achieved for the constant rotation angle ratio 1: 1 from the rotary piston to the rotary commutator.
  • If the rotary piston has teeth with convex tooth flanks as the second internal toothing, the rotary commutator is then driven by the fact that the gear extensions of the rotary commutator, which are evenly distributed on the circumference, also protrude directly into the second internal toothing of the rotary piston provided with convex circular tooth flanks and the number of extensions is equal to that Is the number of teeth of the second internal toothing, the extensions are in turn defined according to the guidelines for a circular arc transmission according to claim 6 and have concave tooth flanks.
  • In similar rotary piston machines, which do not belong to this class, it is known that the rotary commutator is driven by the rotary piston via a wobbling cardan shaft. However, this solution cannot be adopted in the machine according to the invention, since the drive shaft is guided through the rotary commutator in the central region of the machine. There is indeed the possibility that a wobbling hollow shaft is provided in the area between the rotary commutator of the control part, which is provided at both ends with a third or fourth external toothing, one end with the second internal toothing of the rotary piston and the other end with a third internal toothing of the rotary commutator combs. However, this possibility is practically out of the question, since the input or output shaft that is carried out would have to be made much weaker in this area, as a result of which inadmissible deflections of the gear shaft could occur with the same dimensions.
  • The embodiment of the displacement teeth, in this case the first inner or. External gearing has a significant influence on the efficiency of the machine. One of the sources of loss is the normal force with which the tooth heads of the first external toothing are moved against one another on the tooth heads of the associated internal toothing. This head tooth force is smaller, the smaller the pressure angle of the toothing. Since these tooth heads slide on each other, there are friction losses which can also lead to wear and tear at the same time. A design which has been tried and tested many times in practice is characterized in that this first internal or external toothing is a trochoid toothing, the teeth of the first internal toothing being described as described in another context (see EP-PS 43899, which is considered to be disclosed in the context of this description) have approximately trapezoidal shape with convexly curved flanks and heads, and that the pitch circle of the first internal toothing extends outside the circle around the center of the first internal toothing through the lower third of the tooth height of the first internal toothing.
  • At high speeds of these hydrostatic rotary piston machines, an embodiment has also proven itself in which the teeth of the first internal toothing are formed by rollers rotatably mounted in the housing. These are stored in the housing with a certain plain bearing clearance so that a hydrodynamic plain bearing is created between the roller and the housing due to the working fluid.
  • In the type of rotary piston machines on which the invention is based, the rotary piston has an annular shape. The hydrostatic force acts on half of its outer circumference and tends to deform this annular body into an oval. This deformation must not be greater than the backlash of the first internal toothing permits if the rotary piston is to rotate freely in the internal toothing of the housing. If this oval deformation becomes too large, the rotary piston jams, resulting in poor efficiency and high wear on the machine. For this reason, the deformation rigidity of the rotary piston must be optimized. This is achieved if the internal toothing of the rotary piston has the same number of teeth as its external toothing and if the rotary piston is made of a material with a large modulus of elasticity.
  • Further advantageous design options for efficient production of the machine according to the invention are described in the subclaims.
  • The invention is explained in more detail below on the basis of exemplary embodiments with reference to the accompanying schematic drawings. Show it:
  • Fig. 1
    a longitudinal section through an embodiment of a hydrostatic rotary piston machine, only the longitudinal pinning, but not the longitudinal screw connection, being shown for better clarity;
    Fig. 2
    a cross section along the section line AA of Figure 1, wherein the internal teeth of the rotary piston has concave tooth flanks;
    Fig. 3
    the same cross section, the internal toothing of the rotary piston having a convex tooth flank shape;
    Fig. 4
    a cross section along the section line BB of Figure 1, wherein the internal toothing of the rotary piston has concave tooth flanks as in Figure 2;
    Fig. 5
    the same cross section, the internal toothing of the rotary piston having a convex tooth flank shape;
    Fig. 6
    a cross section along the section line AA of Figure 1, wherein the internal toothing of the positive toothing in the housing is formed by cylindrical rollers;
    Fig. 7
    a cross section along the section line CC of Figure 1, and
    Fig. 8
    a variant with a central control section.
  • The rotary piston machine 101 shown in the figures has, in addition to the longitudinal screw connection, not shown in the longitudinal section, an input or output shaft 9 which is stably supported in two tapered roller bearings 10 to the left and right of the hydraulic part. The machine is leak-free sealed to the outside by a shaft sealing ring 50, the leak oil lines and leak oil return lines serving to relieve the pressure of the seal in the low pressure range are not shown for the sake of clarity. The shaft 9 is provided with strong external toothing 8 (8a with convex and 8b with concave tooth flanks 28a and 28b), which transmits the input and output torque, the internal toothing 7 (7a with concave and 7b with convex tooth flanks 29a and 29b) the rotary piston 5 combs. This circles with the eccentricity e around the shaft 9 and, since the shaft is mounted coaxially to the housing internal toothing 4, also inside the housing 3. The design requirement must therefore be met that the center distance of the internal gear transmission between shaft 9 and rotary piston 5 is equal to that The center distance of the internal gear between the rotary piston 5 and the housing 3 must be. The machine also has a drum-shaped rotary commutator 11 which is mounted in the control part 2 in a pressure-tight manner but with running play. It has radially outwardly open control slots 12 and 13 which are alternately axially offset and evenly distributed on the circumference. The control slots are connected to the connections 19 and 20 for the pumped medium both via circumferential grooves 15 and 16 and also via inner grooves 17 and 18. The mode of operation of such a rotary commutator for controlling, for example, a generic rotary piston machine is known to the person skilled in the art (cf. OMM hydraulic motor from Danfoss) and therefore need not be explained in more detail. The rotary commutator supplies and disposes of the displacer part 1 via the radial control channels 21 and 22 and via the axial channels 23 with pressure media.
  • As can be seen from FIGS. 2 to 6, the channels 23 open into the tooth spaces 26 of the housing internal teeth 4, which together with the associated external teeth 6 of the rotary piston 5 form the working spaces of the hydrostatic machine in a known manner. The mode of operation of these known internal gear pumps or motors is also known to the person skilled in the art and need not be explained further. With correct control of the inflow and outflow of the working medium from the working spaces 26a and 26b by the rotary commander 11, for example, all the working spaces 26a to the left of the center line 40 are with the inlet 19, all to the right thereof lying working spaces 26b with the drain 20 in connection. If, as in the case of a hydraulic motor, the inlet 19 is under high pump pressure, the outlet 20 is approximately under atmospheric pressure, then the rotary piston 5 is rotated clockwise with a high torque around the engagement point 27 of the housing teeth 4 in the example of FIGS . The size and uniformity of this torque depends crucially on the number of teeth and the pitch circle diameter of the external toothing of the rotary piston. This leads to a linear relationship between the absorption volume of the machine per revolution of the rotary piston around its own axis and its torque. Large number of teeth and large eccentricity e result in high machine performance in a given installation space.
  • The rotary piston 5 now outputs its torque in the form of a large tooth force at the point of engagement 44 between its internal toothing 7 and the external toothing 8 of the shaft on the output shaft 9.
  • The efficiency of this power transmission between the rotary piston and the shaft is influenced by the pressure angle of the engaged gears. The toothing according to FIG. 3 is superior to that of FIG. 2 by approx. 4%, provided that it is optimized in terms of construction. This optimization must be carried out on the drawing board and at the same time computationally, which need not be explained in detail here and is known to a person skilled in the art.
  • A bending-resistant shaft 9 is important for the successful operation of such a rotary piston machine, which is why it must be striven for that the external toothing 8 preferably placed on it in one piece has the largest possible diameter. At the same time, however, the rotary piston 5 should also be as rigid as possible. It can be seen in particular from FIG. 6 that it is advantageous if the internal teeth of the rotary piston 5 have the same number of teeth as the external teeth 6 thereof.
  • As can be seen in particular in FIG. 1, little space remains for the 1: 1 drive of the rotary commutator 11 by the rotary piston 5. In the rotary piston machine according to the invention, a completely new path has been taken to solve this task, as can be seen particularly clearly in FIG. If a circular arc shape is selected for the inner tooth flanks 29a of the rotary piston 5, then a suitable circular arc tooth 30 (with a convex tooth flank 30a) can also be found for a 1: 1 ratio between rotary piston 5 and rotary commutator 11. The active intervention points are designated with the numbers 31 and 32. The regulation for the calculation and construction of this 1: 1 toothing can be found in the patent specification (CH patent application "circular arc transmission" from the same filing date) or the features of claim 5. The projections 14, which are designed as teeth and have the arc-shaped tooth flank 30a, can be produced in one piece with the rotary commutator 11, for example using the sintering process. Since the rotary commutator does not consume any power, the tooth load is practically zero.
  • 5 shows such a circular toothing between the rotary piston 5 and the rotary commutator 11, in which the tooth shape 29b is convex. The rules for designing and calculating the counter tooth flank 30b are the same. Much more stable tooth-shaped extensions 14b are obtained on the rotary commutator 11.
  • A machine with a very high and proven wear resistance is shown in FIG. 6, in which the internal toothing 4 of the housing is produced from rotatable, hardened and ground rollers 34. Here there is the possibility that the rollers 34 are supported hydrodynamically on an oil film in the gap 35 between the roller and the housing, so that the efficiency of this displacement toothing is improved. The manufacturing effort is of course correspondingly higher, since the lubricating film may only be a few micrometers thick, so that the inside shape of the housing must be correspondingly precise.
  • 7 shows the arrangement of the radial slots 12 and 13 of the rotary commutator 11, as well as the arrangement of the channels 21 and 22 and the cylindrical channels 23 in cross section. Here you can also see the screws 36 for the longitudinal screwing of the machine and the screws 37 for separately screwing the control housing 38 to the connection housing 39.
  • The variant shown in section in FIG. 8 shows the control part 2a with the connections 19a, 20a closer to the output end of the shaft 9 than in the variant according to FIG. This enables a radial feed, and the radial bearing forces for the bearings 10 are even better distributed. This also results in less flow restriction losses at high speed, because there are no large curvatures; longer sealing distances "L" on the commutator and therefore better volumetric efficiency with the same overall length as Fig.1; Easier to install and a more market-compliant arrangement of the connections. The other components correspond to those of the other figures and are therefore not described in detail.
  • The embodiments shown in the drawing are only intended to give examples of a rotary piston machine according to the invention. It is also conceivable that the rotary commutator cannot be flowed through radially, but axially, as is preferred in some cases. Likewise, the inflow and outflow connections - as often preferred - can be arranged radially rather than axially.

Claims (11)

  1. A hydrostatic rotary piston machine having a displacement part, acting as a driven part or output part, and an adjacent control part which serves for supplying the displacement part with operating fluid and removing the latter from the said displacement part, the displacement part having a first rigid housing with a first inner tooth system which interacts with a rotatable, eccentrically arranged rotary piston having a first outer tooth system, which rotary piston has a second inner tooth system which intermeshes with a second outer tooth system on a centrally mounted shaft which also passes at least through the control part and is mounted at both ends, the difference between the number of teeth of the first inner tooth system and outer tooth system being 1, wherein the second inner tooth system and outer tooth system have a difference of at least two in the number of teeth - the outer tooth system in each case being that with the smaller number of teeth - and a rotary commutator of the control part being coupled to the rotary piston via an arc gear having a transmission ratio of 1 : 1.
  2. A hydrostatic rotary piston machine as claimed in claim 1, wherein the second inner tooth system has concave tooth flanks which are in particular round, and the shape of the tooth flanks of the second outer tooth system on the driven shaft or output shaft is determined for rolling on the second inner tooth system of the rotary piston. (Fig. 2)
  3. A hydrostatic rotary piston machine as claimed in claim 1, wherein the second inner tooth system has convex, in particular round, tooth flanks, and the shape of the tooth flanks of the second outer tooth system of the shaft is determined for rolling on the second inner tooth system. (Fig. 3)
  4. A hydrostatic rotary piston machine as claimed in any of claims 1 to 3, wherein the rotary commutator has gear extensions which point toward the displacement part and intermesh directly with the second inner tooth system of the rotary piston. (Fig. 1, 4)
  5. A hydrostatic rotary piston machine as claimed in any of claims 2 to 4, wherein the gear extensions projecting from the rotary commutator are in the form of teeth which are distributed uniformly along an arc, have round tooth flanks and engage the second inner tooth system, the radius of which is smaller, by a factor corresponding to the eccentricity of the rotary piston machine, than the radius of the preferably round tooth flanks of the gear extensions, or vice versa. (Fig. 4,5)
  6. A hydrostatic rotary piston machine as claimed in claim 2 or 5, wherein the number of gear extensions is equal to the number of teeth of the second inner tooth system, the gear extensions having concave tooth flanks. (Fig. 4)
  7. A hydrostatic rotary piston machine as claimed in claim 3 or 5, wherein the number of gear extensions is equal to the number of teeth of the second inner tooth system, the gear extensions having convex tooth flanks. (Fig. 5)
  8. A hydrostatic rotary piston machine as claimed in any of claims 1 to 7, wherein the first inner or outer tooth system is a trochoidal tooth system, each tooth of the first inner tooth system having an approximately trapezoidal shape with convex flanks and tips, and the pitch circle of the first inner tooth system runs outside the circle about the arc centerpoint of the first inner tooth system through the lower third of its tooth height. (Fig. 2)
  9. A hydrostatic rotary piston machine as claimed in any of the preceding claims, which comprises one or more of the following features:
    a) The rotary piston, but preferably also the first housing holding this piston, and the rotary commutator and, if required, the control disk and the second housing are made of a sintered metal and/or ceramic powder;
    b) the inner tooth system of the rotary piston has the same number of teeth as its outer tooth system, and
    c) the teeth of the first inner tooth system are formed by rollers rotatably mounted in the housing.
  10. A hydrostatic rotary piston machine as claimed in any of the preceding claims, wherein, in the region of the rotary commutator, the control part is divided coaxially into a control housing and a connection housing and has a pressure-tight screw union, the connection housing preferably holding a bearing for the shaft.
  11. A hydrostatic rotary piston machine as claimed in any of the preceding claims, wherein the shaft input or output transmitting the power is closer to the displacement part than to the control part. (Fig. 8)
EP19890119514 1988-10-24 1989-10-20 Hydrostatic rotary piston machine Expired - Lifetime EP0367046B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CH3943/88 1988-10-24
CH394388A CH679062A5 (en) 1988-10-24 1988-10-24

Publications (2)

Publication Number Publication Date
EP0367046A1 EP0367046A1 (en) 1990-05-09
EP0367046B1 true EP0367046B1 (en) 1993-09-15

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890119514 Expired - Lifetime EP0367046B1 (en) 1988-10-24 1989-10-20 Hydrostatic rotary piston machine

Country Status (6)

Country Link
US (1) US5056994A (en)
EP (1) EP0367046B1 (en)
JP (1) JP2820290B2 (en)
CH (1) CH679062A5 (en)
DE (2) DE58905616D1 (en)
HK (1) HK58394A (en)

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US5228846A (en) * 1991-11-25 1993-07-20 Eaton Corporation Spline reduction extension for auxilliary drive component
EP0761968A1 (en) * 1995-09-08 1997-03-12 Siegfried A. Dipl.-Ing. Eisenmann Valve for a gerotor motor with hydrostatic bearing
DE19536060C2 (en) * 1995-09-28 1998-06-18 Danfoss As Hydraulic machine
GB2313411B (en) * 1996-05-25 1999-10-13 Concentric Pumps Ltd Improvements in drive systems
US5860884A (en) * 1996-10-28 1999-01-19 Tecumseh Products Company Variable speed transmission and transaxle
US6019584A (en) * 1997-05-23 2000-02-01 Eaton Corporation Coupling for use with a gerotor device
EP1074740B1 (en) * 1999-08-03 2001-12-19 Siegfried A. Dipl.-Ing. Eisenmann Hydrostatic rotary piston machine
EP1074739A1 (en) * 1999-08-03 2001-02-07 Siegfried A. Dipl.-Ing. Eisenmann Hydrostatic rotary piston machine
DE19961401C2 (en) * 1999-12-20 2002-06-27 Sauer Danfoss Nordborg As Nord Hydraulic machine
US6524087B1 (en) 2000-08-03 2003-02-25 Siegfried A. Eisenmann Hydrostatic planetary rotation machine having an orbiting rotary valve
US20030070429A1 (en) * 2001-08-21 2003-04-17 Jolliff Norman E. Hydrostatic transmission
CH701073B1 (en) * 2004-07-22 2010-11-30 Siegfried A Dipl-Ing Eisenmann Hydrostatic rotary engine.
US7395665B2 (en) * 2006-02-07 2008-07-08 White Drive Products, Inc. Hydraulic transaxle for garden care vehicle
JP5916078B2 (en) * 2011-12-07 2016-05-11 株式会社ジェイテクト Inscribed gear pump
DE102011122027B3 (en) * 2011-12-22 2013-04-11 Böhm + Wiedemann Feinmechanik AG Hydrostatic rotary piston motor used as hydraulic motor, has rotor which is dimensioned such that center of diameter of rollers comprises eccentricity to arc center of roller seat, by contact of rollers with rotor external toothing
WO2013133641A1 (en) * 2012-03-07 2013-09-12 Kim Woo Kyun Two-stage compressor unit and compressor system having same
CN102900665A (en) * 2012-10-16 2013-01-30 李庆中 Inside engaged gear pump or gear motor device with multilayer structure
DE102014015809A1 (en) 2014-10-24 2016-04-28 Man Truck & Bus Ag Hydraulic wheel drive for a motor vehicle and method for its operation
DE102015001235A1 (en) * 2015-02-03 2016-08-04 Man Truck & Bus Ag Method for operating a gear pump and gear pump
EP3441613A1 (en) 2017-08-07 2019-02-13 Siegfried A. Eisenmann Hydrostatic gearwheel rotary piston machine

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US3288078A (en) * 1964-08-25 1966-11-29 Trw Inc Hydraulic device
US3456559A (en) * 1967-07-21 1969-07-22 Reliance Electric & Eng Co Rotary device
US3658449A (en) * 1970-10-16 1972-04-25 George V Woodling Orbital fluid pressure device for exerting a force
US3784336A (en) * 1971-12-10 1974-01-08 Sperry Rand Corp Power transmission
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DE3026222C2 (en) 1980-07-10 1987-10-01 Siegfried Alexander Dipl.-Ing. 7960 Aulendorf De Eisenmann
US4411606A (en) * 1980-12-15 1983-10-25 Trw, Inc. Gerotor gear set device with integral rotor and commutator
US4741681A (en) * 1986-05-01 1988-05-03 Bernstrom Marvin L Gerotor motor with valving in gerotor star
DE3632155A1 (en) * 1986-09-22 1988-03-31 Johann Langmaier Engine or machine

Also Published As

Publication number Publication date
HK58394A (en) 1994-06-17
JPH02245485A (en) 1990-10-01
EP0367046A1 (en) 1990-05-09
US5056994A (en) 1991-10-15
DE58905616D1 (en) 1993-10-21
CH679062A5 (en) 1991-12-13
DE8912593U1 (en) 1990-01-25
JP2820290B2 (en) 1998-11-05

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