EP2690252A1 - Pompe à engrenages internes trochoïdes - Google Patents

Abstract

The machine has a filler (4) that is designed such that in the filler is formed inside the rotor side. The filler is formed integrally with the primary wall (11). The axial length of the primary wall in the axial direction parallel to the axes in portion is greater than the width (B) of the external rotor (2) and the inner rotor (3). The protruding portion (14) is formed axially into the recess which extends axially in the opposite secondary wall (16) of filler.

Description

The invention relates to a trochoid internal gear machine for operating as a hydraulic pump or hydraulic motor according to the preamble of claim 1.

Such trochoid internal gear machines are characterized by an advantageous centric design with a relatively small number of teeth difference between the outer rotor and the inner rotor, by a cheap, elongated tooth engagement line and thus by a low-noise running of the gear transmission. In the case of using this machine as a hydraulic pump or as a hydraulic motor, there are further advantages, namely small delivery and thus small pressure pulsations. Such trochoid internal gear machines are the quietest known hydraulic gear machines.

Known hydrostatic gear machines according to the preamble have a Trochoidenverzahnung having internally toothed external rotor, also called ring gear, preferably nine to fifteen teeth whose tooth root width is preferably about twice the tooth space width at the root circle and wherein the distance of the mutually facing flanks of adjacent teeth of the ring gear on the Partial circle measured measured the distance of the tooth flanks of a tooth of the ring gear on the pitch circle is preferably about the same, with a preferably two or three teeth less than the ring gear having externally toothed internal rotor, also called pinion, which meshes with the ring gear. The effective tooth profile of the one wheel, so the ring gear or pinion, is equal to the determined by rolling this wheel on the other wheel profile. In the place of deepest tooth engagement opposite free space between the Head circles of the gears, a filler is arranged, on which the Zahnkopeflächen the gears slide sealingly along. The term "Trochiodenverzahnung" should not only denote a Trochoid gearing in the strict sense, but also one in which at least one wheel has a Zykloidenverzahnung or a circular arc gearing, since in the latter the tooth flank profile is very similar to a Trochoidenverzahnung in the strict sense. Furthermore, in the present invention, the trochoidal shape of the tooth flanks can also be replaced by other similar curves, since it depends less on a trochoidal shape of the tooth flanks than on the "approximate" tooth shape which usually arises in trochoid toothing. Such a trochoid internal gear machine, on which the present invention is based, is known from Austrian patents no. AT 330 582 B and AT 358 932 B known.

The versions published there have a number of teeth difference of preferably two or possibly also three teeth between the outer rotor or the ring gear and the inner rotor or the pinion. In the case of a tooth number difference of two, the free space between the tooth tip circles at the point compared to the deepest tooth engagement is very narrow, so that there arranged filler is very thin. Moreover, the number of sealing points along the filler piece is only between two and three on the inner rotor and between three and four on the outer rotor due to the teeth of the inner rotor and the outer rotor sliding along there.

The filler must sit exactly and immovably in the housing. From the AT 330 582 B an attachment of the filler is known, wherein the filler near its two located in the circumferential direction of the gear machine ends axial projections or, in other words, in its central region has two notches. The lying on both sides of the notches projections are pressed into two exactly complementary shaped openings of the two pumping chamber of the pump in the axial direction limiting flat end faces of the end plates. The projections on both sides of the notches can also be glued or soldered into the recesses. The filler is preferably made of a well-tempered steel but sliding softer material, such as a corresponding sliding bronze.

If this machine is operated with high working pressures, the attachment of the filler left and right in the housing walls in both the radial and in the circumferential direction is exposed to high loads. Because of the radial pressure differences between the existing there tooth chambers of the inner rotor within the filler and the tooth chambers of the outer rotor outside the filler, the filler must be made of a high-strength plain bearing alloy to endure the bending oscillations permanently. Like in the FIG. 4 the Austrian patents no. AT 330 582 B recognizable, the design of the filler and especially the anchoring of it in the side walls is very complex and expensive.

In practice, a difference in number of teeth of two in combination with the described attachment method of the filler has been found to be advantageous because the filler in this case has a smaller thickness, is subjected to lower loads and in the AT 330 582 B described attachment of the projections of the filler in the recesses in the housing is thus protected against knocking.

The object of the invention is to improve the known from the prior art trochoid internal gear such that it is characterized by a simpler structure, a lower production cost, a reduced noise level, increased volumetric efficiency and increased pressure performance.

This object is achieved by the realization of the features of the independent claim. Features which further develop the invention in an alternative or advantageous manner can be found in the dependent claims.

The invention is based on the recognition that an increase in the number of teeth difference between the number of teeth of the internal teeth of the external rotor and the number of teeth of the external teeth of the internal rotor brings from two to three significant advantages.

Such a tooth number difference causes the pressure increase along the filler is much smaller, the line of action is more favorable due to larger tooth flank circles and reduces the tooth flank pressure on the meshing. This results in an extremely low noise level during operation of the machine.

Due to twice as many points of intent along the filler in the circumferential direction and smaller axial volumetric losses towards the shaft in the axial gap increases the volumetric efficiency considerably. In addition, the filler is much more stable.

Compared with a conventional trochoid internal gear machine with a number of teeth difference of two and a gear ratio of 11: 9 between outer rotor and inner rotor has a machine with the number of teeth difference of three and a gear ratio of 12: 9 a 16% lower speed of the ring gear, since the square of (9:12) x (11: 9 ) equal to 0.8403. As a result, the friction loss is significantly reduced, so that the mechanical efficiency is improved.

Due to smaller specific pressure on the shaft bearings, twice as many sealing points along the filler, a much smaller Striebeck'schen pressure on the tooth flanks in the tooth engagement, a smaller shaft deflection and thus less edge stress in the shaft bearings, it is possible to increase the pressure performance of Trochoiden- Internal gear machine to increase up to 200 to 250 bar.

In the art, such a trochoid internal gear machine with one of two to three increased number of teeth difference has been considered virtually impossible to produce. The attachment of the filler to the housing is already a significant challenge in a machine with a number of teeth difference of two. As in the AT 330 582 B represented the filler must sit exactly and immovably in the housing. The in the AT 330 582 B described attachment is suitable for a relatively narrow and lower loads exposed filler. Since the filler is significantly narrower at a tooth number difference of two than a tooth number difference of three and the attachment of the filler is already a big challenge with a tooth number difference of two, which is associated with high manufacturing and assembly costs, applies a durable trochoidal internal gear machine with three teeth difference in the Series production since the revelation in the AT 330 582 B and the AT 358 932 B described invention towards the end of the 70s still as unworkable.

Between the outer rotor and the inner rotor axially limited tooth spaces are formed by a first wall and a second wall.

According to the invention, the filler is formed integrally with the first wall. In other words, the filler according to the invention is not a separate part which must be connected to the first wall firmly and immovably, but the filler is itself part of the first wall. Preferably, the first wall in turn forms a part of the housing, so that the filler piece is integrally connected to the first housing wall and thus a part of the housing of the trochoidal internal gear machine.

Due to the one-piece connection of the filler to one of the walls, in particular to one of the housing walls, eliminating an anchoring of which in the circumferential direction in contrast to the previously known machine. Experiences from the past show a notch effect on the transition of the filler into the housing wall. In order to avoid a notch effect in the transition of the filler into the housing wall, it is advantageous that the filler ends in the circumferential direction with a sufficient radius pass into the housing wall.

Because of the above-mentioned bending vibrations on the filler, it is for the operation of the machine as a high-pressure machine of great advantage if the filler is formed slightly longer in the axial direction than the width of the moving set, so that it supports for its free end in a recess in the opposite wall, in particular, the opposite housing wall, can protrude. It is advantageous if the immediately adjacent to the moving set housing wall consists of a relatively thinner dimensioned steel plate, which is provided on the running side with a sliding bearing running layer. Inexpensive, this overlay is made as one of an aluminum-tin layer bonded by atomic bonding to the steel plate in the roll-plating process. In this intermediate plate, a recess can now be punched, which can take the free end of the filler fit, so that it is extremely stable against radial vibrations. This stampable intermediate plate also has the advantage that dimensionally accurate suction and pressure kidneys for the filling and emptying of the conveyor cells of the moving set can be produced inexpensively.

In the following the invention will be described generally.

The trochoid internal gear machine according to the invention, hereinafter also referred to as machine for short, is suitable both as a hydraulic pump, the shaft of the machine being driven to generate a hydraulic flow, and as a hydraulic motor, wherein the machine is subjected to a hydraulic pressure in order to drive the shaft ,

The machine has a housing in which an internally toothed external rotor with a trochoid toothing is rotatably mounted about a first geometric axis. The outer rotor is formed by a ring gear with an internal toothing having a number of teeth of nine to fifteen teeth. The internal teeth or the external rotor have a width B in the direction parallel to the first geometric axis. The housing encloses the Outrunner all around. The housing is preferably composed of a plurality of coupled housing sections.

Also in the housing is eccentrically to the outer rotor an externally toothed inner rotor rotatably mounted about a second axis. The second axis is spaced parallel to the first axis. The inner rotor is rotationally fixed on a led out of the housing shaft, which serves as a hydraulic drive in the case of operation of the machine as a drive shaft and in the case of operation as a hydraulic motor as an output shaft. The external teeth of the inner rotor, which is formed by a pinion on the shaft, meshes in a section with the internal teeth of the outer rotor. The internal gear or the inner rotor have the width B in the direction parallel to the first and to the second geometric axis. Thus, the outer rotor and the inner rotor have the same width B. The toothing geometries of the inner teeth of the outer rotor and the outer teeth of the inner rotor correspond to each other so that they can interlock, but they have a tooth number difference of three. In other words, the inner rotor has three teeth less than the outer rotor. The number of teeth of the outer rotor and the number of teeth of the inner rotor are divisible by 3, so that the possible number of teeth ratios 12:15, 9:12 and 6: 9 result between the inner rotor and the outer rotor.

The tooth flank profile of the external rotor is formed by a number of geometric flat circles with the same radii corresponding to the number of teeth of the internal teeth of the external rotor. The centers of these flat circles lie on a common, concentric to the outer rotor circle whose center lies on the first axis. Each of the flat circles spans one out of every three adjacent teeth imaginary group of teeth of the internal teeth of the outer rotor, wherein the flat circle each defines the opposite tooth flanks of the two outer teeth of the tooth group, so that the internal toothing is formed by a circular arc toothing.

The exact shape of the tooth flank of the inner rotor results from the mathematical calculation of the engagement points between the two tooth flanks of the outer rotor and the inner rotor by a virtual rolling according to the kinematics during the rotation of the moving set. As a parameter serves the angular position of the eccentric axis to the gears.

Due to the larger number of teeth difference, the tooth flank radii are considerably larger, so that the Striebeck flank pressure is greatly reduced. The maintenance of a lubricating film between the loaded tooth flanks allows higher working pressures.

Since the teeth of the outer rotor and the inner rotor have different diameters, resulting geometric free tooth spaces between the outer rotor and the inner rotor outside the range of the deepest meshing of the internal teeth and the external teeth. These free tooth spaces are bounded radially by the internal teeth of the external rotor and the external teeth of the internal rotor, as well as axially by a first wall and a second wall extending parallel to the first wall. The walls extend on planes to which the first axis and the second axis each form a geometric normal, and have a width of the inner and outer rotor corresponding distance to each other. The rotatable inner and outer rotor are passed so close to the walls, that there is a sealing contact between the walls and the inner and outer rotor.

One of the two walls is formed integrally with a part of the housing and thus constitutes a housing wall.

Opposite the region of the deepest tooth engagement of the outer rotor and the inner rotor is a free space between the Zahnkopfkreiszylinderfläche the inner rotor and the Zahnkopfkreiszylinderfläche the outer rotor opposite. To understand under the Zahnkopfkreiszylinderflächen in the imaginary geometric circular cylindrical surface, which passes tangentially to the tooth tips of the teeth of the teeth. This free space between the two circular cylinder jacket surfaces of the teeth has a crescent shape or, in other words, a crescent shape or sickle shape in cross section, to which the axes form geometric normals.

In this crescent-shaped free space an approximately crescent-shaped filling piece is arranged, which fills this free space over most of its length in the circumferential direction. Under approximately crescent-shaped is to be understood that the filler has the basic shape of a crescent, in other words a crescent moon or a sickle, but the tips of the crescent are rounded or cut off. Therefore, the filler does not completely fill this crescent-shaped free space along its length in the circumferential direction, but for the most part. In other words, the vast majority of the free area is filled with the filler. The filler is immovably coupled to the housing and stands still during rotation of the inner rotor and the outer rotor. The filler is designed such that on the filler inside the rotor side Zahnkopfkreiszylinderflächen the outer teeth of the inner rotor and the outer rotor side of the Zahnkopfkreiszylinderfläche the internal teeth of the outer rotor seals slide along. Thus, the filler divides the tooth space, which is formed due to the different numbers of teeth between the outer rotor and the inner rotor, in a first tooth space and a sealingly separated from this second tooth space. The first tooth space is connected to a first hydraulic connection via a particularly kidney-shaped first opening in one of the walls. The second tooth space, sealingly separated therefrom, is connected to a second hydraulic connection via a particularly kidney-shaped second opening in one of the walls. The kidney-shaped openings are also called suction and pressure kidneys.

According to the invention, the filler piece is formed integrally with the first wall, ie with one of the two walls of the tooth space. This means that the wall and the filler piece are a single part, in particular a forged part, e.g. from an aluminum alloy, a cast part or a milled part. Thus, the first wall and the filler are made of the same material.

The axial extent of the filler piece from the first wall in the axial direction parallel to the axes is greater than the width of the outer rotor and the inner rotor at least in one section. In other words, the axial extent of the filler piece from the first wall, at least in a portion of the filler, for example in an extension extension, greater than the width of the outer rotor and the inner rotor, so that at least a portion of the filler protrudes beyond the geometric plane of the second wall , This across the width of the outer rotor and the inner rotor and thus the geometric plane of the second wall in the axial direction protruding portion of the filler, for example, the extension extension projects axially into a recess which is formed axially in the opposite second wall into it. This recess in the second wall is formed such that the filler is fixed in the radial direction and / or in the circumferential direction with respect to the axes. Preferably, the recess in the second wall has a shape such that the protruding into it portion of the filler is accommodated in the radial direction accurately in the recess, so that the filler is stably supported against radial vibrations.

Preferably, the filler rooted to the first wall passes in its ends in a radius which prevents a sharp corner and thus a fatigue-affecting notch in the first wall in both circumferential directions, whereby a fatigue break at the location of the transition of the filler in the housing wall is avoided.

In a further development of the invention, the circumferential extent, ie the circumferential length of the portion of the filler, which protrudes into the recess accurately seen in the circumferential direction is so less than the circumferential extent of the remaining filler that the minimum radial thickness of the portion of the filler in the radial direction at least 50% to 70% of its maximum radial thickness. In other words, the partial section protruding into the recess is at least 50% to 70% thick in its edge region, relative to its geometrically defined tooth head circle cylindrical surfaces, at its thickest point, which lies opposite the point of maximum tooth engagement of the toothings. alternative the subsection formed in particular as an extension extension comprises only about 50% to 70% of the circumferential length, ie the circumferential extent of the filler. Thus, the recess in the second wall does not have to be made as thin by far as in the above-mentioned, known as the prior art machine. The remaining left and right of the extension extension rest of the circumferential length of the filler serves to hold down or supporting the second wall, so that it does not stand out in this area of the terminal housing, if this is to be prevented.

In an advantageous development of the invention, the second wall, in which, in particular, the recess for the partial section of the filler piece is formed, or alternatively the first wall, which is formed integrally with the filler piece, is formed by an intermediate plate. In the first case, this intermediate plate preferably has a flat, thin, plate-like shape and consists in particular of a machined and, in particular, coated sheet metal part, eg a sheet steel. In a variant of the invention, the intermediate plate on the tooth spaces and thus the outer and inner rotor side facing a, in particular applied to a steel sheet, running layer. This running layer consists, for example, of an aluminum-tin layer rolled in the roll-plating process, in particular AlSn6. The recess for receiving the partial section of the filler piece, the suction and pressure kidneys connected to the hydraulic connections for supplying and disposing the tooth spaces with hydraulic working fluid and screw through-holes for screws which hold the housing together, can be inexpensively formed in the intermediate plate as a punching die. or laser cutting recesses be formed, as the Machining a simple sheet metal part is associated with very low production costs.

Alternatively, however, there is also the possibility that the intermediate plate forms the first wall and thus is formed integrally with the filler. In this case, the filler is, for example, a forged part, a machined casting or a milled part, which has a plate-like basic shape and from which the filler protrudes vertically.

A further aspect of the invention comprises that the housing has a front housing in which the shaft is mounted, an intermediate housing which radially encloses the outer rotor and the inner rotor and in which the outer rotor is mounted, and a connection housing in which the shaft is mounted and which includes the hydraulic connections for supply and disposal of the tooth spaces with working fluid comprises. The intermediate plate, on which the second wall is located, axially adjacent to the intermediate housing and is thus located either between the intermediate housing and the connection housing, in which case the first wall and the filler are formed integrally with the front housing, or between the intermediate housing and the front housing, in which case the first wall and the filler are integrally formed with terminal housing. The front housing, the intermediate housing, the intermediate plate and the connection housing are sealingly sandwiched axially in the radial direction, in particular by means of axially extending screws.

In a further development of the invention, the front housing is formed integrally with the first wall and the filler, wherein the intermediate plate axially between the intermediate housing and the terminal housing is disposed and separates the intermediate housing and the terminal housing from each other.

The terminal housing consists for example of a cast iron alloy containing iron, the front housing consists in particular of a forged aluminum alloy, or vice versa. In one possible embodiment, the intermediate housing consists of a pearlitic iron alloy produced in a powder metallurgical process.

To increase the surface pressure for a better Reibschuss between the intermediate housing and the adjacent walls of the intermediate plate and the front housing or the connection housing, it is possible to provide the intermediate housing on its axial sides with recesses.

For supporting the shaft, in a variant of the invention in the axial direction to the left and right of the outer rotor and the inner rotor shaft bearings can be arranged, which are formed as a ternary 3-material bearing bushes. If the trochoid internal gear machine is to be operated as a hydraulic motor, it is advantageous if needle bearings are arranged to the left and to the right of the outer rotor and the inner rotor.

The trochoid internal gear machine according to the invention is described in more detail below purely by way of example with reference to a concrete embodiment shown schematically in the drawings in the form of several sections and views, wherein further advantages of the invention will be discussed.

Figur 1

einen senkrecht zu den Achsen geführten Querschnitt durch die Trochoiden-Innenzahnradmaschine, wobei der Aussen- und Innenläufer mit dem quergeschnittenen Füllstück sichtbar sind,

Figur 2

einen Längsschnitt durch die Maschine entlang der Schnittlinie A-A der Figur 1,

Figur 3

eine Darstellung des an aus der ersten Wand herausragenden Füllstücks mit seinem in die gegenüberliegende zweite Wand hineinragenden Teilabschnitts in Form eines Verlängerungsfortsatzes, der in Unfangsrichtung kürzer ausgebildet ist als die gesamte Füllstückslänge,

Figur 4

eine Draufsicht auf die Ausnehmung in der gegenüberliegende zweiten Wand, in die der Verlängerungsfortsatzes des Füllstücks passgenau eingeführt werden kann,

Figur 5

eine Detailansicht auf einen Zahnkopf des Innenläufers mit einer Schabekante,

Figur 6

einen Längsschnitt durch die Maschine entlang der Schnittlinie B - B der Figur 1 mit Hydraulikanschlüssen als Saug- und Druckanschlüsse,

Figur 7

eine Draufsicht auf die Maschine,

Figur 8

eine Seitenansicht auf einen der Hydraulikanschlüsse der Maschine und

Figur 9

einen senkrecht zu den Achsen geführten Detailquerschnitt durch die Trochoiden-Innenzahnradmaschine in Form eines Detailansicht der Figur 1.

Show in detail

FIG. 1

a cross-section taken perpendicular to the axes through the trochoidal internal gear machine, wherein the outer and inner rotor are visible with the cross-cut filler,

FIG. 2

a longitudinal section through the machine along the section line AA of FIG. 1 .

FIG. 3

3 shows a representation of the filler piece protruding from the first wall with its partial extension projecting into the opposite second wall in the form of an extension extension which is shorter in the circumferential direction than the entire filler length;

FIG. 4

a plan view of the recess in the opposite second wall into which the extension extension of the filler can be accurately inserted,

FIG. 5

a detailed view of a tooth head of the inner rotor with a scraping edge,

FIG. 6

a longitudinal section through the machine along the section line B - B of FIG. 1 with hydraulic connections as suction and pressure connections,

FIG. 7

a top view of the machine,

FIG. 8

a side view of one of the hydraulic connections of the machine and

FIG. 9

a guided perpendicular to the axes detail cross section through the trochoidal internal gear machine in the form of a detailed view of FIG. 1 ,

The following are the FIGS. 1 to 9 , which show the same embodiment from different views and in different degrees of detail, describe together, wherein in the explanation of the individual figures in part to the above already explained features and reference numerals will not be discussed again.

As in the Figures 2 . 6 and 8th 1, the trochoidal internal gear machine for operating as a hydraulic pump or hydraulic motor has a housing 1 which consists of a front housing 49, in which a shaft 30 is mounted in a shaft bearing 25, an intermediate housing 27, which has an external rotor 2 and one on the shaft 30 shrunk-in inner rotor 3 radially encloses and in which the outer rotor 2 is rotatably mounted, and a connection housing 26, in which the shaft 30 is also mounted in a shaft bearing 24 and which hydraulic connections 33, 34, composed.

The internally toothed external rotor 2 rotatably mounted in the housing 1 about a first axis 44 has a trochoidal internal toothing with twelve teeth which have a width B, as in FIG FIG. 2 shown.

The also in the housing 1 eccentrically to the outer rotor 2 rotatably mounted about a second axis 45, with the outer rotor 2 meshing inner rotor 3 is externally toothed and has the same width B as the outer rotor 2. The inner rotor has nine teeth, so three teeth less than of the Outrunner, the numbers of teeth are each divisible by three. The external toothing of the inner rotor 3 communicates with the internal toothing of the external rotor 2 in the upper section in a force-transmitting manner. Between the outer rotor 2 and the inner rotor 3 tooth spaces 41 and 42 are formed, as in the FIGS. 1 and 9 shown. These tooth spaces 41 and 42 are axially bounded by a first wall 11 integrally formed with the front housing 49, in other words part of the front housing 49, and one of the first wall 11 spaced axially parallel second wall 16, as in FIG FIG. 2 shown.

As in the FIGS. 1 and 9 2, the tooth flank profile of the external rotor 2 is defined by a number of geometric flat circles 10 corresponding to the number of teeth of the external rotor 2. In FIG. 1 one of the twelve flat circles 10 is shown with the common radius r. In the FIG. 9 two flat circles 10 and 10 'are shown for illustration. The geometric centers 39 and 39 'of these flat circles 10 and 10' are uniformly distributed on a common, concentric to the outer rotor 2 circle 37, also called pitch circle, in the FIGS. 1 and 9 is shown in dashed lines and the center lies on the first axis 44. Each of the total of twelve flat circles 10, 10 'each spans one of three adjacent teeth 46, 47 and 48 existing tooth group 38 of the external rotor 2. So a total of twelve tooth groups 38 of twelve flat circles 10, 10' spans. Each of the twelve flat circles defines each of the opposing tooth flanks 7 and 8 of the two outer teeth 46 and 48 of the respective tooth group 38, as in FIGS FIGS. 1 and 9 illustrated. By these large tooth flank radii of the tooth flanks 8 and 9 is calculated for the Striebeck specific tooth flank pressure very low values for a good formation of a sufficient lubricating film between the loaded tooth flanks.

Since in relation to the overall size of the machine, the tooth tip diameter of the inner rotor 3 is much smaller compared to the known machine, the specific load of the shaft bearings 24 and 25 according to the FIG. 2 lower. This allows a significant increase in the printing performance of the machine.

As also in the FIGS. 1 and 9 recognizable, the deepest tooth engagement of the outer rotor 2 and the inner rotor 3 takes place above. Opposite this place of the deepest tooth engagement, so down in the FIGS. 1 and 9 , a free space between the Zahnkopfkreiszylinderfläche 5 of the inner rotor 3 and the Zahnkopfkreiszylinderfläche 6 of the outer rotor 2 is clamped. In this free space between the Zahnkopfkreiszylinderflächen 5 and 6, an approximately crescent-shaped filler 4 is arranged, which is formed integrally with the front housing 49 and with the first wall 11. Thus, this filler 4 is immobile coupled to the housing 1.

This in FIG. 1 and 2 shown, hatched from top left to bottom right filler 4 fills to a large extent the space between the Zahnkopfkreiszylinderflächen 5 and 6, which slide with the smallest possible running clearance on the filler 4 along. The filler 4 is thus designed such that on the filler 4 inside rotor side the Zahnkopfkreiszylinderflächen 5 of the inner rotor 3 and the outer rotor side, the Zahnkopfkreiszylinderfläche 6 of the outer rotor 2 seals slide along. The tooth spaces are thus in one with a first hydraulic port 33, FIGS. 6 and 7 , connected first tooth space 41, FIGS. 1 and 9 , and one of them sealingly separated, with a second hydraulic port 34, FIGS. 6, 7 and 8th Subdivide, connected second tooth space 42. As can be seen, the inner rotor 3 between three and four teeth, the outer rotor 2 between four and five teeth for sealing between the tooth spaces 41 and 42 along the filler 4 are available. This is of great importance for high printing performance. At the same time, the pressure rise along the filler 4 is correspondingly gentle, so that the hydraulic pressure pulsations and thus their noise development are advantageously small.

Likewise in FIG. 2 is the filler 4 as part of the drive-side wall 11 of the front housing 49 at its radially largest point 20, FIG. 3 , shown in longitudinal section. As in FIG. 2 shown is the axial extent of the filler 4 of the first wall 11 in the axial direction parallel to the axes 44 and 45 greater than the width B of the outer rotor 2 and the inner rotor 3, so that over the width B of the outer rotor 2 and the inner rotor. 3 axially projecting in the axial direction portion 14 of the filler 4 axially in a recess 15 which is axially formed in the opposite second wall 16, protrudes accurately. This formed as an extension extension 14 section protrudes into the right second wall 16 with a tight fit, so that extreme bending deflections in the radial direction are not possible. In other words, the recess 15 in the second wall 16 has a shape such that the protruding into it portion 14 of the filler 4 is received in the radial direction accurately in the recess 15, so that the filler 4 is stably supported against radial vibrations.

Thus, the connection housing 26, in the FIG. 2 shown on the right, can be made of a high-strength cast alloy, between the outer and inner rotor 2 and 3 and the cast-iron terminal housing 26, an intermediate plate 17, for example, a machined steel sheet, arranged with a run-side side run layer 18. The running layer 18 may consist of an aluminum-tin layer, in particular AlSn6, rolled by the roll-plating method. The intermediate plate 17 can then inexpensively receive the required recess 15 for the extension extension 14 of the filler 4. Thus, this intermediate plate 17 also forms the second wall 16. A recess 15 to be machined in the connection housing 26, as required in the known machine, is thus saved. Likewise, a recess 15 to be machined is saved in the drive-side first wall 11 of the front housing, because the filler 4 is turned there in one piece, for example, by turning by means of an eccentric chuck, as is practiced today in large numbers. The recess 15 for receiving the extension extension 14 of the filler 4, with the hydraulic connections 33 and 34 connected suction and pressure kidneys 21 and 22, FIGS. 1 and 9 for the supply and disposal of the tooth spaces 41 and 42 with hydraulic working fluid, and screw through-holes 23, FIG. 2 , can be produced inexpensively in the intermediate plate 17 by means of punching or by means of laser cutting.

As in the Figures 2 . 6 and 8th shown, the front housing 49, the intermediate housing 27, the intermediate plate 17 and the terminal housing 26 in the radial direction sealing sandwiched axially by means of bolts 43 braced together. The front housing 49 is formed integrally with the first wall 11 and the filler 4. The intermediate plate 17 is disposed axially between the intermediate housing 27 and the terminal housing 26 and separates the intermediate housing 27 and the terminal housing 26 from each other.

The FIG. 3 shows the filler 4 in perspective with its extension extension 14, which detects only about 60% of the circumferential length of the filler. Thus, the recess 15 in the second wall 16 in the intermediate plate 17 does not have to be made as thin as in the known machine mentioned above. The left and right in the FIG. 3 shown rest of the Füllstückslänge 35 and 36 in the circumferential direction serves to hold down the intermediate plate 17 so that it does not stand out in this area of the terminal housing 26. In addition, the circumferential extent of the portion 14 of the filler 4, which projects into the recess 15, as seen in the circumferential direction is less than the circumferential extent of the remaining filler 4, that the minimum radial thickness 19 of the portion 14 of the filler 4 in the radial direction over 50% 70% of its maximum radial thickness is 20, as in FIGS. 3 and 4 illustrated. The rooted to the first wall 11 filler 4 goes in both circumferential directions at its ends 12 in a radius 13 in the first wall 11 in order to avoid a notch effect in the transition of the filler 4 in the first wall 11.

In the FIG. 4 the shape of the recess 15 in the second wall 16 of the intermediate plate 17 can be seen, in which the extension extension 14 of the filler 4 can be introduced.

The tooth tips of the inner rotor 3 are provided in a known manner, each with a scraping edge 29, see FIG. 5 which are able to withstand the relatively soft surface of the inner inner cylindrical surface 5 of the filler 4 to produce a very small chip processing to compensate for the manufacturing tolerances when editing this surface. For this purpose, the fully assembled machine is driven, for example, as an extremely low speed pump under high working pressure. Under these operating conditions, the shaft 30 shifts in the shaft bearings 24 and 25 according to the course of Gümbel'schen semicircle of the sliding bearing theory on the surface of the shaft bearings 24 and 25, ie in the extreme eccentric displacement of the shaft 30 and thus also the inner rotor 3. Due to the low rotational speed of the inner rotor 3 in this process called the "lane", the scraping edges 29 of the teeth of the inner rotor 3 optimally work the inner cylindrical surface 5 of the filler 4 for the smallest possible clearance. In this case, a highly viscous oil is used, whereby the resulting machining chips are filtered out. If the machine later works in high-speed operation, the shaft 30 moves away from the bearing surface in accordance with the sliding bearing theory, so that no high, unacceptable friction power can arise between the tooth tips of the inner rotor 3 and its inner cylinder surface 5, but at the same time optimally small Leckölspalt between the tooth tips and the filler 4.

In the FIG. 6 It is shown that the bearing blocks 31 and 32 are resiliently designed for the shaft bearings 24 and 25, so that at a given deflection of the shaft 30 under high load at high working pressure no inadmissible edge support arise at the bearing edges. In the case of the application of the machine as a hydraulic pump so-called ternary ternary bearing bushes with a galvanically applied lead-tin-copper overlay, which provide a high adaptability to the Wave deformation and especially have an excellent Schmerbeinbettungsfähigkeit. In the case of the application of the machine as a hydraulic motor, it is necessary that the shaft plain bearings are replaced by rolling bearings, for example by needle bearings, so that the engine can be easily approached even under load. When using plain bearings, the engine would be under self-locking condition at zero speed.

As in FIG. 2 shown, the intermediate housing 27 is provided on its axial sides with recesses 28 to increase the surface pressure for a better Reibschuss between the intermediate housing 27 and the adjacent walls of the front housing 49 and the intermediate plate 17.

The invention is not limited to the embodiment shown schematically and illustrated in the drawings. For example, it is possible that the filler 4 is not formed in the wall of the front housing 49, but in the wall of the terminal housing 26. In addition, it is possible to form the filler 4 in one piece with the intermediate plate 17.

Claims (14)

Trochoid internal gear machine for operation as hydraulic pump or hydraulic motor with An internally toothed external rotor (2) rotatably mounted in a housing (1) about a first axis (44) and having a trochoidal toothing having nine to fifteen teeth with a width (B), A externally toothed internal rotor (3) with the width (FIG. 2), which is rotatably mounted about a second axis (45) eccentrically to the outer rotor (2), meshing with the outer rotor (2) and connected to a shaft (30); B), wherein formed between the outer rotor (2) and the inner rotor (3) by a first wall (11), in particular with a part of the housing (1) integrally formed first housing wall, and a second wall (16) axially limited tooth spaces are, An approximately half-moon-shaped filler piece (4), which is immovably coupled to the housing (1) and which is located in a free space between the tooth tip circle cylinder surface (5) of the inner rotor (3) opposite the deepest tooth engagement of the outer rotor (2) and the inner rotor (3) ) and the Zahnkopfkreiszylinderfläche (6) of the outer rotor (2) is arranged and fills this free space over most of its length in the circumferential direction,
in which The filling piece (4) is designed in such a way that on the inside of the rotor the tooth-head circle surfaces (5) of the internal rotor (3) and on the outside rotor side slide the tooth-head circular surface (6) of the external rotor (2) in a sealed manner, The tooth spaces are subdivided into a first tooth space (41) connected to a first hydraulic connection (33) and a second tooth space (42) sealingly separated therefrom and connected to a second hydraulic connection (34), The difference of the numbers of teeth between the outer rotor (2) and the inner rotor (3) is equal to three, • the number of teeth of the external rotor (2) and the number of teeth of the internal rotor (3) is divisible by 3 and The tooth flank profile of the external rotor (2) of a number of geometric flat circles (10) corresponding to the number of teeth of the external rotor (2), the centers (39) of which lie on a common circle (37) concentric with the outer rotor (2) about the first axis (44), - Each span one of three adjacent teeth (46, 47, 48) existing tooth group (38) of the outer rotor (2) and each of which defines the mutually remote tooth flanks (7, 8) of the two outer teeth (46, 48) of the tooth group (38),
is formed, characterized in that The filler piece (4) is formed integrally with the first wall (11), The axial extension of the filler (4) from the first wall (11) in the axial direction parallel to the axes (44, 45) is greater than the width (B) of the outer rotor (2) and the inner rotor (3) at least in one section ) and • an over the width (B) of the outer rotor (2) and the inner rotor (3) in the axial direction protruding portion (14) of the filler (4) axially in one Recess (15), which is formed axially in the opposite second wall (16) protrudes fitting exactly. Trochoid internal gear machine according to claim 1,
characterized in that
the filling piece (4) rooted to the first wall (11) in both circumferential directions at its ends (12) in a radius (13) which prevents a sharp corner and thus a fatigue-affecting notch in the first wall (11) passes. Trochoid internal gear machine according to claim 1 or 2, characterized in that
the circumferential extent of the section (14) of the filler (4) projecting into the recess (15) is smaller in the circumferential direction than the circumferential extension of the remaining filler (4) such that the minimum radial thickness (19) of the section (14 ) of the filler (4) in the radial direction is at least 50% to 70% of its maximum radial thickness (20). Trochoid internal gear machine according to one of claims 1 to 3,
characterized in that
the recess (15) in the second wall (16) has a shape such that the partial section (14) of the filler piece (4) protruding into it is received in a precise fit in the recess (15) in the radial direction, so that the filler piece (4 ) is stably supported against radial vibrations. Trochoid internal gear machine according to one of claims 1 to 4,
characterized in that
the first wall (11) or the second wall (16) is formed by an intermediate plate (17). Trochoid internal gear machine according to claim 5,
characterized in that
the intermediate plate (17) on the tooth spaces (41, 42) facing side, in particular applied to a steel sheet, running layer (18). Trochoid internal gear machine according to claim 6,
characterized in that
the running layer (18) applied to the intermediate plate (17) consists of an aluminum-tin layer, in particular AlSn6, rolled by the roll-plating method. Trochoid internal gear machine according to one of claims 5 to 7,
characterized in that The second wall (16) is formed by the intermediate plate (17), The recess (15) for receiving the section (14) of the filler (4), • with the hydraulic connections (33, 34) connected suction and pressure kidneys (21, 22) for supply and disposal of the tooth spaces (41, 42) with hydraulic working fluid and • Screw through holes (23) in the intermediate plate (17) are formed as punching or laser cutting recesses. Trochoid internal gear machine according to one of claims 5 to 8,
characterized in that
the housing (1) A front housing (49) in which the shaft (30) is mounted, An intermediate housing (27) radially enclosing the outer rotor (2) and the inner rotor (3), and A connection housing (26), in which the shaft (30) is mounted and which has the hydraulic connections (33, 34) for the supply and disposal of the tooth spaces (41, 42) with working fluid, comprising The second wall (16) is formed by the intermediate plate (17), The intermediate plate (17) is axially adjacent to the intermediate housing (27), • the front housing (49), the intermediate housing (27), the intermediate plate (17) and the terminal housing (26) in the radial direction sealingly sandwiched axially with each other, in particular by means of axially extending screws (43) are braced. Trochoid internal gear machine according to claim 9,
characterized in that The front housing (49) is formed integrally with the first wall (11) and the filling piece (4), • the intermediate plate (17) is arranged axially between the intermediate housing (27) and the connection housing (26) and • the intermediate plate (17) the intermediate housing (27) and the connection housing (26) separated from each other. Trochoid internal gear machine according to claim 10,
characterized in that • The terminal housing (26) consists of a ferrous cast alloy and / or • the front housing (49) consists of a forged aluminum alloy. Trochoid internal gear machine according to one of claims 9 to 11,
characterized in that
the intermediate housing (27) consists of a pearlitic iron alloy produced in a powder metallurgical process. Trochoid internal gear machine according to one of claims 9 to 12,
characterized in that
the intermediate housing (27) is provided on its axial sides with recesses (28) for increasing the surface pressure for a better friction fit between it and the adjacent walls. Trochoid internal gear machine according to one of claims 1 to 13,
characterized in that • In the axial direction to the left and right of the outer rotor (2) and the inner rotor (3) shaft bearings (24, 25) are arranged, which are formed as a ternary 3-material bushings, or • To use the trochoidal internal gear machine as a hydraulic motor to the left and right of the outer rotor (2) and the inner rotor (3) needle roller bearings are arranged.

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