DE102004021216B4 - High-pressure internal gear machine with multiple hydrostatic bearings per ring gear - Google Patents

Abstract

High-pressure internal gear machine, in particular internal gear pump (10), with a housing (11), an externally toothed pinion (12) rotatably mounted in the housing (11) and a rotating with the pinion (12) and rotating in the housing (11) mounted, with the pinion (12) meshing, internally toothed ring gear (13), wherein in a radially outwardly facing peripheral surface (14) of the ring gear (13) opposite housing part (15) and / or bearing part, several, to the ring gear (13) Pressure pockets (18.1, 18.2) which are open towards and delimited by sealing webs (17.1 to 17.8) are provided for hydrostatic mounting of the one-piece and / or one-piece ring gear (13), characterized in that the sealing webs (17.1 to 17.8) are provided with relief grooves (23.1, 23.2, 23.3, 23.4) which are open towards the ring gear (13) and which extend in a common relief channel which extends in the axial direction (19) and is open towards the ring gear (13) l (24) flow out.

Description

The invention relates to a high-pressure internal gear machine (pump or motor) according to the preamble of claim 1.

Such internal gear machines have become common knowledge for many years. In the case of internal gear pumps, efforts are often made to realize the highest possible pump pressures and delivery volumes with the smallest possible outside dimensions of the pump and the simplest possible, cost-effective design.

From the DE 41 04 397 A1 is a sickle-free internal gear pump with a one-piece pinion has become known, which is according to a first embodiment variant with a single internally toothed ring gear in engagement, which is rotatably mounted in a housing part. This has an axial extension which corresponds to the width of the toothing of the ring gear and the pinion. Between the tooth tips of pinion and ring gear, a radially movable sealing element is provided in each of the tooth tips of one of the two gears in order to improve the sealing effect. This design is complicated and the resulting flow rates are limited due to manufacturing technology with respect to a simple broadening of the ring gear limits regarding the precision and the surface quality of the teeth.

In order to promote higher volumes of fluid at the same outside diameter of the pump was, according to a second embodiment of the DE 41 04 397 A1 proposed to equip the pump with two or more coaxially arranged ring gears, which are commonly engaged with a one-piece pinion and which bear against each other at axial contact surfaces, which are thus arranged in a single, common pump chamber. In this construction, however, these axial contact surfaces are not stabilized, so that due to the forming during operation of the internal gear pump force and torque ratios, the ring gears are hydraulically pressed apart at their axial contact surfaces and inclined relative to each other, so be tilted, with the result of a correspondingly high wear.

To solve this problem was in accordance with the DE 41 35 725 A1 proposed, in the region of the axial contact surfaces of the adjacent ring gears viewed from the side of the pressure port of the housing part forth, provide a counter or abutment. This is intended to ensure that the two ring gears are pressed against one another at their axial contact surfaces during pump operation and that there is no rotation or canting of the two ring gears relative to each other. In this construction, each ring gear is assigned in each case one pressure pocket which extends over a circumferential region of the respective ring gear and opens into a pressure port. In that regard, this construction corresponds to the technical teaching according to the aforementioned first embodiment of the DE 41 04 397 A1 while in there treated and also mentioned above second embodiment, two or more ring gears associated with such a pressure pocket.

From the DE 27 44 730 A1 is a high-pressure gear machine (pump or motor) with a driven external gear, a revolving internally toothed ring gear and a sickle-shaped or semi-sickle-shaped sealing element carrier between pinion and ring gear, which are received in a tubular housing part. In the inner wall of the tubular housing part, a pressure-side pocket for forming a hydrostatic bearing for the ring gear is provided.

However, all these constructions have the disadvantage that in a broadening of one or more of the ring gears for the purpose of a corresponding increase in the achievable delivery volumes and / or at higher pump pressures, as a result of adjusting during pump operation different pressure conditions, a corresponding deflection and tilting each of the Ring gears is unavoidable. As a result, there is a correspondingly increased wear of the respective ring gear and / or the housing part which supports this, up to a total failure of the pump due to so-called edge eaters.

From the US Pat. No. 1,624,099 A is a gear pump with the features of the preamble of claim 1 become known. In this gear pump, the internally toothed ring gear is rotatably mounted in a receiving this lantern ring relative to this, which in turn is rotatably mounted in the housing. The lantern ring has at regular circumferential angles to each other in the circumferential direction offset openings, which are arranged in two offset from one another in the axial direction circumferentially arranged rows. Each two axially adjacent openings of the openings are arranged in an axial row. The openings are separated by web-shaped ring parts of the lantern ring. By means of these ring parts can only achieve a limited seal. During operation of this gear pump, uneven force or pressure conditions may occur. This can lead to malfunctions and increased wear.

It is therefore an object of the invention to provide a high-pressure internal gear machine of the type mentioned above, with the simple and inexpensive construction and high delivery volumes higher pressures of the fluid medium at a low-wear and trouble-free operation over a long time can be realized.

This object is solved by the features of claim 1.

The fact that in a radially outwardly facing peripheral surfaces or lateral surfaces of the ring gear opposite housing part and / or bearing part, which is supported directly or indirectly on this housing part or in the housing, several, open to the ring gear and limited by sealing webs pressure pockets for hydrostatic bearing of the one-piece and / or integrally formed ring gear are provided, it is achieved that the introduction of force between the ring gear and this part stored evenly, d. H. the deformation of the ring gear and the housing part and / or bearing part is significantly reduced at the high pressures acting. In other words, the core is to hydrostatically store a single ring gear several times by using several pressure pockets. This makes it possible, for example, based on a ring gear of a certain width, drive significantly higher pressures than before, without causing increased wear or even a total failure of the system. When using a single, comparatively wide ring gear per delivery chamber, sufficiently high delivery volumes can be achieved at elevated pressures in a particularly simple and cost-effective design.

The fact that the pressure pockets delimiting sealing webs are provided with relief gear open to the ring, which open into a common, extending in the axial direction and the ring gear open discharge channel, can be an improvement of the seal and a homogenization of forming during operation of the internal gear machine Achieve force or pressure conditions.

The bearing part can preferably be a bearing ring or a bearing bush. The bearing part can be supported directly on an inner wall of the housing. But it can also be supported on a compensation ring or a bearing ring received therein or a bearing bush, for example a so-called annular pump.

Advantageous embodiments of the invention will become apparent from the dependent claims.

According to a preferred embodiment it can be provided that the sealing webs delimiting the pressure pockets are interrupted to form a pressure channel connecting the pressure pockets and open towards the ring gear. As a result, a particularly simple and cost-effective production of a common pressure channel opening into the respective pressure pockets is possible.

According to a particularly advantageous embodiment, the above object is also achieved in that the ring gear and / or the ring gear circumferentially bearing housing part and / or bearing part, preferably which is supported directly or indirectly on this housing part or in the housing, at its peripheral or lateral surface or is designed concavely rounded at its opposite circumferential or lateral surfaces in the axial direction or are. The ring gear and / or this bearing housing part is or are therefore preferably designed crowned.

In this case, one makes use of the knowledge that viewed in the pressure range and in the axial direction along the ring gear and the opposite housing part an uneven pressure or force distribution with a force or pressure maximum and respectively falling to the axial sides of the ring gear down forces or pressures occurs , The result is the already mentioned deflections of the ring gear and this bearing housing part. As a result of these comparatively simple measures, it is thus likewise possible to achieve a more even or even more uniform introduction of force between the ring gear and the housing part which supports this. As a result, higher pressures are mobile, without it would lead to increased wear or total failure of the internal gear machine.

Further advantages, features and aspects of the invention can be taken from the following description part, in which several preferred embodiments of the invention are described with reference to the figures.

Show it:

1 a cross section through an internal gear designed as an internal gear pump internal gear machine with a crescent-shaped filler;

2 a partial longitudinal section of the internal gear machine along the section lines 2-2 in 1 ;

3 a cross section through the housing of the internal gear machine according to 1 along the section lines 3-3 in 4 or in 6 ;

4 a longitudinal section through the housing of an internal gear machine according to a first embodiment;

5 a partial longitudinal section of one opposite 4 90 degree rotated cutting plane in the region of a pressure channel of the internal gear machine;

6 a longitudinal section through the housing of the internal gear machine according to 1 according to a second embodiment;

7 a partial longitudinal section in a opposite

6 90 degree rotated cutting plane in the region of a pressure channel of the internal gear machine.

In the 1 and 2 is one as internal gear pump 10 designed high-pressure internal gear machine shown. This includes a housing 11 , one in the case 11 rotatably mounted, externally toothed pinion 12 and one with the pinion 12 accompanying and in the housing 11 circulating, with the pinion 12 meshing, that is in meshing internally toothed ring gear 13 respectively. 43 ,

The pinion 12 is non-rotatable with a drive shaft 29 connected and is about a in the axial direction 19 extending axis of rotation 39 in the direction of rotation 35 rotatable. The ring gear 13 respectively. 43 is rotatable about an axis of rotation which is eccentric to the axis of rotation 39 of the pinion 12 is arranged.

In the crescent-shaped gap 40 between the teeth of the pinion 12 and the corresponding teeth of the ring gear 13 respectively. 43 Here is a crescent-shaped filler 20 arranged, which is designed to be divided longitudinally in the embodiment shown.

The housing 11 has a suction inlet channel 33 on, which is arranged in a zone in which upon rotation of the pinion 12 in the direction of rotation 35 the teeth of the pinion 12 or the teeth of the ring gear 13 respectively. 43 disengaged. To the suction inlet channel 33 closes one to the ring gear 13 respectively. 43 open and in the circumferential direction 21 extending suction bag 36 extending over a portion of the radially outwardly facing peripheral surface 14 . 45 or lateral surface of the ring gear 13 respectively. 43 extends. In a zone where under a rotation of the pinion 12 in the direction of rotation 35 the teeth of the pinion 12 or the ring gear 13 respectively. 43 here is one opposite the suction inlet channel 33 in the direction of rotation 35 offset by 270 degrees arranged pressure outlet channel 34 in the case 11 intended. This extends from the over a peripheral region of the ring gear 13 extending pressure pockets 18.1 . 18.2 or on the ring gear 43 extending pressure pocket 48 also related to the pinion 12 radially outward.

The pressure pockets 18.1 . 18.2 or the pressure pocket 48 are to the ring gear 13 respectively. 43 opened. The inflow of the fluid to be pumped or pressure medium, preferably oil, from the suction inlet channel 33 to the interior of the internal gear pump 10 ie to the tooth gaps between the pinion 12 and the ring gear 13 respectively. 43 , whereby the promotion of the fluid is effected via radial openings 37.1 . 37.2 in the ring gear 13 respectively. 43 , These breakthroughs 37.1 . 37.2 are arranged in pairs axially spaced from each other and each go from the lateral surface or peripheral surface 14 . 45 of the ring gear 13 respectively. 43 out and open in the tooth base of the ring gear 13 respectively. 43 ,

At the toothing 30 from pinion 12 and ring gear 13 respectively. 43 lies on the front side to both axial sides in each case an axial disc 25.1 . 25.2 sealingly. Each of the two axial discs 25.1 and 25.2 points to their toothing 30 facing surface on a not shown in detail pressure field. In the wall of the axial disc 25.1 adjacent housing part 41 and in the wall of the axial disc 25.2 adjacent housing part 42 is each a pressure field 38 provided by the respective axial disc 25.1 and 25.2 from the outside against the action of the inner pressure field can be acted upon such that the respective axial disc 25.1 and 25.2 in all operating states of the internal gear pump 10 a sufficient sealing contact with the pinion 12 and the ring gear 13 respectively. 43 maintains. The design and operation of the pressure fields on axial discs and their structural design are known in the art and therefore require no further explanation at this point.

The gears 30 of the pinion 12 and the ring gear 13 respectively. 43 each have an axial width 31 on, which is smaller than the axial extent or axial width 32 of the housing part 15 respectively. 44 in the area between the two axially arranged housing parts 41 and 42 , The ratio of diameter and width 31 of the ring gear 13 respectively. 43 is preferably greater than 0.5, in particular greater than 0.57.

According to the preferred embodiment variants of the invention shown in the figures, the ring gear that is the only one piece as well as one piece and one piece is here 13 a plurality of here two axially spaced pressure pockets 18.1 and 18.2 assigned. These are in the direction of circulation 21 extending grooves 22.1 . 22.2 designed, which are substantially parallel to each other. The pressure pockets 18.1 and 18.2 are of a plurality of sealing webs 17.1 to 17.8 limited, on the one hand during operation of the internal gear pump 10 a good, ie lossless seal between the ring gear 13 and this bearing housing part 15 and by the other hand, under the formation of pressure pockets 18.1 . 18.2 a plurality of here two hydrostatic bearings for the ring gear 13 are formed. This means that when operating the pump as good as possible and low-loss sealing of the pressure pockets 18.1 . 18.2 through the respective sealing webs 17.1 to 17.8 realized to the suction side, to a sufficient hydrostatic bearing of the ring gear 13 forming a minimum lubricating film between the ring gear 13 and this circumferentially overlying housing part 15 to reach.

According to the particular in the 1 . 2 . 4 and 5 shown first embodiment is each pressure pocket 18.1 and 18.2 in each case completely from sealing webs 17.1 to 17.4 limited. Each is as a groove 22.1 . 22.2 designed printing bag 18.1 . 18.2 here by four sealing webs, namely two each in the direction of rotation 21 parallel sealing webs extending 17.1 and 17.4 axially bounded and further by two each to be substantially perpendicular, ie in the axial direction 19 extending sealing webs 17.2 and 17.3 in the circumferential direction 21 limited. They run in the circumferential direction 21 extending sealing webs 17.1 and 17.4 essentially parallel to each other and also in the axial direction 19 extending sealing webs 17.2 and 17.3 are essentially parallel to each other. The two between the pressure pockets 18.1 and 18.2 extending sealing webs 17.4 are parts of the printed bags 18.1 and 18.2 Separating sealing web 17.5 ,

To improve the seal on the one hand and to equalize the forming during operation of the internal gear pump force or pressure conditions are the sealing webs 17.1 and 17.5 each with a ring gear 13 open relief groove 23.1 . 23.2 . 23.3 Mistake. These relief grooves 23.1 . 23.2 . 23.3 each extend in the direction of rotation 21 essentially parallel to each other. They lead into a common, in the axial direction 19 extending and the ring gear 13 open discharge channel 24 which in turn is in the suction inlet channel 33 empties.

In the pressure pockets 18.1 and 18.2 each opens a pressure channel 26.1 . 26.2 ( 5 ). Each of these pressure channels 26.1 and 26.2 the other ends inside the housing 11 , here within the ring gear 13 bearing housing part 15 into a common pressure main channel 27 , These, in the pressure pockets 18.1 and 18.2 opening pressure channels 26.1 . 26.2 may preferably be designed as inclined bores, which are not shown in detail in the drawings.

According to an alternative embodiment of the invention, which in the 1 . 6 and 7 is shown, it can be provided that the pressure pockets 18.1 and 18.2 limiting sealing webs 17.1 . 17.2 . 17.3 . 17.6 . 17.7 . 17.8 under training a the pressure bags 18.1 and 18.2 connecting and to the ring gear 13 towards open pressure channel 28 are interrupted. In the 6 and 7 are the same parts with the same reference numerals designed as in the aforementioned first embodiment. In this case, preferably the pressure pockets 18.1 and 18.2 connecting pressure channel 28 in the axial direction 19 , This one, the printing bags 18.1 and 18.2 connecting, to the ring gear 13 open pressure channel 28 in turn flows into a main pressure channel 27 , which here the pressure outlet channel 34 formed.

As in 6 it can be seen, so every pocket 18.1 . 18.2 axially bounded by the in the circumferential direction 21 parallel sealing webs extending 17.1 . 17.6 and 17.7 and is in the circumferential direction 21 limited by two perpendicular and again substantially parallel sealing webs 17.2 and 17.3 , The pressure pockets 18.1 and 18.2 connecting and to the ring gear 13 open pressure channel 28 is in the circumferential direction 21 bounded on both sides by mutually parallel sealing webs 17.8 , in turn, parallel to the sealing webs 17.2 and 17.3 are arranged. The sealing webs 17.8 go in the respective, in the circumferential direction 21 extending sealing webs 17.6 and 17.7 over which the two pressure pockets 18.1 and 18.2 axially delimiting on their opposite sides. Likewise, as in the first embodiment, in the second embodiment, the pressure pockets 18.1 and 18.2 limiting sealing webs 17.1 . 17.6 and 17.7 with the ring gear 13 towards open relief grooves 23.1 . 23.3 and 23.4 provided, extending in the direction of rotation 21 extend substantially parallel to each other. In contrast to the first embodiment variant is in the second embodiment, the between the adjacent pressure pockets 18.1 and 18.2 provided relief groove 23.4 unlike all other relief grooves 23.1 . 23.2 . 23.3 not designed fully closed, but ends, limited by the spaced apart in a circumferential distance sealing webs 17.8 ,

It is understood that the invention not only in connection with internal gear machines with filler 20 , But also useful in connection with filler or sickle-free internal gear machines. It is further understood that the invention can be used meaningfully only or also in connection with internal gear machines with axial promotion. In addition, it should be understood that the invention is not limited to axial plates in conjunction with axial compensation 25.1 . 25.2 , but also without axial plates is usable.

Finally, it is understood that the invention also without radial openings 37.1 . 37.2 in the ring gear 13 respectively. 43 is useful.

LIST OF REFERENCE NUMBERS

10

Internal gear pump

11

casing

12

pinion

13

ring gear

14

Peripheral surface of 13

15

housing part

16

Peripheral surface of 15

17

sealing land

17.1

to

17.8

sealing land

18

Printed bag

18.1

Printed bag

19.2

Printed bag

19

axially

20

filling

21

direction of rotation

22.1

groove

22.2

groove

23.1

relief

23.2

relief

23.3

relief

23.4

relief

24

relief channel

25.1

thrust washer

25.2

thrust washer

26.1

pressure channel

26.2

pressure channel

27

Merge main channel

28

pressure channel

29

drive shaft

30

gearing

31

axial width of 30

32

Axial width of 15

33

Suction inlet channel

34

Pressure outlet channel

35

direction of rotation

36

inlet box

37

radial breakthrough

37.1

radial breakthrough

37.2

radial breakthrough

38

pressure field

39

Rotation axis of 12

40

sickle-shaped gap

41

housing part

42

housing part

43

ring gear

44

housing part

45

Peripheral surface of 43

47

Peripheral surface of 44

48

Printed bag

50

Pressure outlet channel

Claims (15)

High-pressure internal gear machine, in particular internal gear pump ( 10 ), with a housing ( 11 ), one in the housing ( 11 ) rotatably mounted, externally toothed pinion ( 12 ) and one with the pinion ( 12 ) and in the housing ( 11 ) mounted circumferentially, with the pinion ( 12 ) meshing, internally toothed ring gear ( 13 ), wherein in a radially outwardly facing peripheral surface ( 14 ) of the ring gear ( 13 ) opposite housing part ( 15 ) and / or bearing part more, to the ring gear ( 13 ) and through sealing webs ( 17.1 to 17.8 ) limited printing bags ( 18.1 . 18.2 ) for the hydrostatic bearing of the one-piece and / or integral ring gear ( 13 ) are provided, characterized in that the pressure pockets ( 18.1 . 18.2 ) limiting sealing webs ( 17.1 to 17.8 ) with the ring gear ( 13 ) open relief grooves ( 23.1 . 23.2 . 23.3 . 23.4 ), which are in a common, in the axial direction ( 19 ) extending and the ring gear ( 13 ) open discharge channel ( 24 ). High-pressure internal gear machine according to claim 1, characterized in that the pressure pockets ( 18.1 . 18.2 ) are arranged axially spaced. High-pressure internal gear machine according to one of claims 1 or 2, characterized in that the pressure pockets ( 18.1 . 18.2 ) in the direction of rotation ( 21 ) extending grooves ( 22.1 . 22.2 ) are designed. High-pressure internal gear machine according to claim 3, characterized in that the grooves ( 22.1 . 22.2 ) are substantially parallel. High-pressure internal gear machine according to one of claims 1 to 4, characterized in that the pressure pockets ( 18.1 . 18.2 ) in the direction of rotation ( 21 ) extending sealing webs ( 17.1 . 17.4 . 17.5 . 17.6 . 17.7 ) are axially limited. High-pressure internal gear machine according to claim 5, characterized in that the pressure pockets ( 18.1 . 18.2 ) axially delimiting sealing webs ( 17.1 . 17.4 . 17.5 . 17.6 . 17.7 ) are substantially parallel. High-pressure internal gear machine according to one of the preceding claims, characterized in that the relief grooves ( 23.1 . 23.2 . 23.3 . 23.4 ) in the direction of rotation ( 21 ). High-pressure internal gear machine according to one of the preceding claims, characterized in that the relief grooves ( 23.1 . 23.2 . 23.3 . 23.4 ) are substantially parallel. High-pressure internal gear machine according to one of the preceding claims, characterized in that the pressure pockets ( 18.1 . 18.2 ) in each case completely from sealing webs ( 17.1 to 17.5 ) are limited. High-pressure internal gear machine according to claim 9, characterized in that in the pressure pockets ( 18.1 . 18.2 ) one or more pressure channels ( 26.1 . 26.2 ) at one end, the other end within the housing ( 11 ) into a common main pressure channel ( 27 ). High-pressure internal gear machine according to claim 10, characterized in that in the pressure pockets ( 18.1 . 18.2 ) pressure channels are designed as inclined bores. High-pressure internal gear machine according to one of claims 1 to 8, characterized in that the pressure pockets ( 18.1 . 18.2 ) limiting sealing webs ( 17.1 . 17.2 . 17.3 . 17.6 . 17.7 . 17.8 ) to form a pressure pockets ( 18.1 . 18.2 ), to the ring gear ( 13 ) open pressure channel ( 28 ) are interrupted. High-pressure internal gear machine according to one of claims 1 to 8 or 12, characterized in that a two adjacent pressure pockets ( 18.1 . 18.2 ) axially limiting sealing web ( 17.6 . 17.7 ) or that the neighboring pressure pockets ( 18.1 . 18.2 ) axially delimiting sealing webs to form a pressure pockets ( 18.1 . 18.2 ), to the ring gear ( 13 ) open pressure channel ( 28 ) is interrupted or are. High-pressure internal gear machine according to one of claims 12 or 13, characterized in that the pressure pockets ( 18.1 . 18.2 ) connecting pressure channel ( 28 ) in the axial direction ( 19 ). High-pressure internal gear machine according to one of the preceding claims, characterized in that the ring gear and / or the ring gear circumferentially bearing housing part and / or bearing part is designed concavely rounded at its peripheral surface or at their opposite peripheral surfaces in the axial direction or are.

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