DE3346519A1 - Positive displacement machine, in particular lobed rotor machine - Google Patents

Abstract

A lobed rotor machine has an inner gear wheel (7), an outer gear wheel (9) which interacts with the inner gear wheel, is arranged eccentrically thereto and which, seen in an axial direction, has arc-shaped bearing locations (29), and further has a casing part (2), which alternately supports the outer gear wheel on its radially outer face and which, seen in an axial direction, has arc-shaped support locations (30), of a multipart casing (1 to 3) held together by fastening means (25), the bearing locations of the outer gear wheel, also seen in an axial direction, matching the support locations of the casing part. In order to provide a lobed rotor machine, in which, seen in an axial direction in each case, the bearing locations and the support locations have arcs with a relatively large diameter, the bearing location of the outer gear wheel are arranged on radially outward-projecting teeth (33), and the support locations of the casing part are arranged in troughs (34) between the teeth. At least the external regions, seen in a peripheral direction, of the teeth of the outer gear wheel and of the troughs between the teeth of the casing part roll off one another (Figure 2). According to a further embodiment of the invention, in a positive displacement machine the commutator is arranged in a torsion-proof manner in the flange casing. <IMAGE>

Description

Displacement machine, in particular a rotary piston machine

The invention relates accordingly to a rotary piston machine the preamble of claim L In a rotary piston machine of the aforementioned Art are the circular arc-shaped bearings on the outside as seen in the axial direction of the external gear is formed in the shape of a muldetfötmig and also seen in the axial direction Arc-shaped support points on the inside of the outer gear surrounding the Used parts as roles. The bearing points and the support points show strong differences in their curvatures, which is why when the support points engage in the bearing points with low damping a high pressing force with loud running noise occurs. Det The space requirement of a rotary piston machine designed in this way is comparatively large (DE-OS 30 15 551).

The present invention is based on the object of a rotary piston machine to create the bearing points and the support points in each case seen in the axial direction Have arches with a relatively large diameter. This task is carried out by the features in the characterizing part of claim 1 solved according to the invention. Practical Tests have shown that the bearing points and the support points each only their outsides meet and that it is enough only to overfibrate Form places with arcs, in particular circular arcs, as large a diameter as possible.

As a result, teeth of the external gear hit the tooth cavities when they engage of Housing part radii very small differences in curvature on each other, which is why almost Surface contact occurs. It can also be between the bearing point and the support point each with a large diameter keep a lubricating film longer than with smaller diameters, whereby a relatively high damping and a considerable smoothness achieved will. Because when curved surfaces lie against each other with force, there is a large diameter the pressure is relatively low, the life of the rotary piston machine increases. Such a machine can also have a space-saving design.

The features of claim 2 are based on a preferred development directed.

The features of claim 3 contribute to reducing the space requirement the rotary piston machine.

An increase in the service life of the rotary piston machine can be achieved by the Features of claim 4 can be achieved.

The features of claim 7 enable the training to be sufficient wider teeth on the housing.

In a further aspect, the invention relates generally on a displacement machine and in particular on a hydraulic motor of the type Planetary gear motor.

A planetary gear motor of the type to which the invention relates is described in DE-OS 31 19 807.4.

The applicant's advertising document RD 14325 / 12.80 also shows a hydraulic motor, to which the present invention relates.

These known hydraulic motors consist essentially of one Control housing with a fixed commutator, a flange housing, a shaft, a Intermediate housing, a displacement set with rotor, a ring gear, inner rollers and External rollers as well as from a control disk.

The pressure medium supply and discharge takes place via corresponding connections, wherein the pressure medium reaches the commutator via ring channels in the control housing. Through the interaction of the control openings of the commutator fixed to the housing and the with the shaft rotating control disk, the pressure medium is in the displacement chambers or passed out of the displacement chambers. The number of displacement chambers corresponds to the number of inner rollers.

About half of the surrounding chambers are under pressure and cause it a torque generating force on the rotor. The rotor performs a slow one Rotational movement around the shaft axis, while the ring gear makes a fast circular movement describes around the shaft axis.

This results in a large number of displacement processes per Shaft rotation. The number of displacement chambers per shaft revolution is the product from the number of inner rollers and from the number of cycloid teeth of the ring gear. The outer rollers support and guide the ring gear.

Although this known rotary piston machine, especially in the Form of a hydraulic motor that works extremely satisfactorily exists a disadvantage of the same is that it is relatively large and thus in cramped conditions Space cannot be used without further ado. In particular is disadvantageous that the control housing with the commutator requires a large amount of space power.

When operating the known machine, the reaction torque that occurs are received in the intermediate housing, the intermediate housing in turn this Deformation forces via the fastening screws (which control housing, intermediate housing and flange housing) on the control housing and thus on the position accuracy of the commutator transmits. This means because of the required precision of the Commutator has a deteriorated control geometry and thus also a deteriorated one Efficiency and a less favorable noise behavior of the known machine.

The invention is based on the disadvantages of the prior art the technology to avoid, and in particular that in the known hydraulic motor occurring disadvantages outlined above.

To solve this problem, the invention provides in the known hydraulic motor, and generally also in a positive displacement or rotary piston machine of the above Kind, before that the commutator is not in the known Way in the control housing, but rather is housed in the flange housing. This has the advantage that the deformation or bending of the intermediate housing and the screws now can no longer be transferred to the commutator fixed to the flange housing. The steering- or the closure housing can be used when accommodating the commutator according to the invention in the flange housing then a simple and compact one, preferably with a shaft bearing be formed plate. Due to the construction according to the invention, the overall length and the cost of materials for the machine is also considerably reduced.

The flange housing is used to attach the hydraulic motor or the Machine and is therefore designed with a greater strength anyway, so that at Placing the commutator in the flange housing does not impair the positional accuracy of the commutator can be caused by the reaction torque.

It should be noted that further preferred embodiments of the invention, in particular, can also be found in the subclaims. Special it should also be noted that in dqm designed according to the invention, the output shaft side Bearing that is subject to higher loads due to external radial forces in many applications is as the counter bearing in the control housing, can be designed so that it over the axial length of the commutator goes beyond. This results in a high bearing force absorption.

Another advantage of the engine designed according to the invention is that due to the rigidity of the flange housing, the commutator is flat sealing without the use of additional seals against the bottom of the flange housing can be pressed in.

According to a preferred embodiment of the invention, it is also provided that an axially shaft-fixed securing element for absorbing axial shaft forces is attached between the control slide and rotor. The securing element is preferably a so-called Seegerring. This achieves in a simple manner that the axial forces either from the control disk to the flange housing or else are transferred from the rotor to the control or termination housing.

Further advantages result from the usual claims and the description and the drawing; In the drawing: FIG. 1 shows a longitudinal section of a rotary piston pump along line I-I in FIG. 2, FIG. 2 shows a cross section along line II-II in FIG. 1, FIG. 3 shows a cross section corresponding to FIG. 2 with a different design of parts.

4 schematically shows a longitudinal section through one according to the invention trained engine; 5 shows a section along line IV - IV in FIG. 4, the rotary piston pump has a housing end part 1, a housing middle part 2 and a cover 3 formed housing 1 to 3. The housing end part 1 is shell-shaped, the housing middle part 2 ring-shaped and the .Did 3 disc-shaped. Basically of the housing end part 1 is a bearing bush 4 in a through hole and in the cover 3 a bearing bush 5 in a blind hole. In the two bearing bushes 4 and 5, a rotor shaft 6 protruding beyond the housing end part 1 is rotatably mounted, with an internal gear 7 by means of a serration in the area of the housing middle part 2 twist is firmly connected. The rotor shaft 6 and the internal gear seated on it 7 can be driven by means of a motor, not shown.

On the circumference of the internal gear 7 are at equal circumferential intervals seven teeth 8 each formed by a roller are arranged, which over the circumference radially protrude. The internal gear 7 is surrounded by an external gear 9 which is corrugated is formed and which will be described in detail below. The external gear 9 and the internal gear 7 form a displacement unit. The teeth 8 are permanent on the external gear 9 and form with this displacement chambers 10 to 16 (FIG 2). The teeth 8 can be rotated in corresponding recesses in the internal gear 7 stored.

Between the displacer unit 7, 9 on the one hand and the housing end part 1 on the other side a control disk 17 is arranged and with the rotor shaft 6 rotatably connected, so that the internal gear 7 and the control disk 17 with the same Rotate the speed The control disk 17 limits the displacement chambers 10 to 16 on the side of the housing end part 1, while on the other side by the Lid are covered on the side. The control disk 17 each has one between the teeth 8 of the internal gear 7 and thus into the displacement chambers 10 to 16.

opening inlet bore 18. These inlet holes are on the The circumference of the control disk 17 is arranged evenly distributed. Your number equals the number of displacement chambers 10 to 16. In the housing end part 1 is a connecting body 19 used non-rotatably, which alternately each have a longitudinal bore 20 to the outside led out transverse channel 21 and on its side adjacent to the control disk 17 each has a corner channel 22.

The longitudinal bore 20 and the corner channel 22 therefore open alternately the side of the connecting body 19 facing the control disk 17. The number of the longitudinal bores 20 and the number of Eckkanile 22 is each around the number 1 is greater than the number of seven displacement chambers 10 to 16 Thus, respectively eight longitudinal bores 20 and eight Eckkanãle 22 available, which alternate on the circumference are arranged evenly distributed. The transverse channel 21 is provided with an annular channel 23 and the corner channel 22 is connected to an annular channel 24. The transverse channel 21 is up connected to a storage container (not shown) and the annular channel 24 with a pressure medium under pressure, also not shown Druckmlttelkreis.

The bearing bush 4, which is firmly inserted into the housing end part 1, passes through it the connecting body 19. The housing end part 1, the housing middle part 2, the cover 3 are connected to one another by means of screws 25.

You external gear 9 has on its inside 8 inwardly protruding, seen in Figure 2 circular arc-shaped projections 26, between which. each, likewise seen in Figure 2, circular arc-shaped recesses 27 each for the engagement of a of the teeth 8 is provided, the radius of the recess 27 being smaller than that of the Projection 26 is. The external gear 9 has casing sections on its outside 28 of a circular cylinder with the diameter Di. In between are seen in FIG Circular teeth 33 are arranged, which are each circular arc-shaped tn their feet Have bearing points 29, which each on the the recesses 27 opposite one another on the opposite side. The radius of the bearing points 29 is denoted by r.

The center of the circle of the bearing points 29 is between the circle determined by the jacket sections 28 on the one hand and the through the radially outermost points of the recesses 27 determined circle on the other hand. In the exemplary embodiment, the ratio r / Di is between 0.155 and 0.145.

The external gear 9 is eccentric to the shaft 6 and by the amount e to the housing 1 to 3 arranged. The housing middle part 2 has on its inside arranged on the side edges of tooth hollows 34, the bearing points 29 of the external gear 9 adapted, also circular arc-shaped support points 30 seen in the axial direction, whose radius R is the sum of the radius r and twice the eccentric distance e is. Inwardly protruding teeth 31 are provided between the tooth recesses 34. Of the Tooth 31 protrudes so far over the bottom of the tooth recess 34 that, as in FIG 2 shown above, between two Teeth 33 fits. in the area of everyone the teeth 31 is a screw 25. The tooth 31 is fully formed and has a tooth tip surface, 32, which is part of a cylindrical casing section is.

The mode of operation of the rotary piston pump corresponds to that according to DE-OS 30 15551.

In the exemplary embodiment according to FIG. 3, only those are the bearing points 29 having teeth 33a of the external gear 9a and the supporting points 30 having Tooth troughs 34a of the housing middle part 2a different from the first exemplary embodiment educated. The teeth 33a are cut off at their radially outer ends and the bottom of the tooth recess 34a is shallower than the bottom of the tooth recess 34. The bearing points 29, which are arranged on both sides, have remained at the foot of the tooth 33a with the radius r on a common arc and on both sides of the tooth recess 33a Support points 30 with the radius R viewed in the axial direction. The height h des Tooth 33a is about 3/4 of the radius r. Seen in the axial direction on a Circumferential head surface of the tooth 33a is supported during operation not on the one also lying on a circumferential circle when viewed in the axial direction The bottom of the tooth recess 34a. The same also applies to the first exemplary embodiment.

In both embodiments it has been shown that the tooth 33, 33a only in the area of its tooth base on the side edges of the tooth cavity 34 or the tooth recess 34a is supported. The cooperating, in the axial direction Seen circular arc-shaped points protrude with bearing point 29 at the external gear 9 or 9a and designated with support point 30 in the housing middle part 2 or 2a. They form a steep pressure angle.

The support point 30, 30a in the middle part of the housing can be provided with a bearing shell be made of a wear-resistant, hardened material.

The bearing point 29 and the Stfitzstelle 30 protrude in the axial direction seen as a circular arc. The circular arc shape results from the fact that the external gear 9 has a circular movement about the axis of the Rotor shaft 6 executes without rotating movement. The number of teeth 33, 33a and the number the teeth 31 are therefore always the same. However, you do not need the number of recesses 27 correspond in the external gear 9.

In Figures 4 and 5 is a rotary or rotary piston machine (sometimes referred to as a displacement machine), namely in the Form of a hydraulic motor 650. The use of the rotary piston machine as a hydraulic motor is preferred, which is why in the following index description also always of a hydraulic motor.

650 is spoken, although this is not to be understood in a limiting sense target.

The hydraulic motor 650 has a preferably composed of three components Housing on, namely the housing consists of a flange housing 66, an intermediate housing 65and a closing case67. These three housing components are held in place by several fastening screws 621 held together, dXe through holes in the closure housing and intermediate housing run and screwed into threaded holes in flange housing 66 are. The bores or intermediate housings are denoted by the reference numeral 620 Wt. A shaft 61 is arranged on the longitudinal axis 625 of the motor 650, namely rotatably mounted by means of a bearing 610a in the flange housing 66 and by means of a Bearing 61Ob in the final housing 67 with the shaft 61 is on the one hand an internal gear or rotor62 and also a control disk6 connected in a rotationally fixed manner. The control disk 64 is connected to the shaft 61 by the toothing arranged at 623 non-rotatably connected and the rotor 62 is through the toothing indicated at 622 rotatably connected to the shaft 61.

The teeth 622,623 would still have an axial movement of Allow rotor 62 and control disk 64, i.e. the shaft 61 could occur if be pulled out of the motor housing by axial forces. To prevent this, a securing element 626 in the form of a circlip is attached to the shaft 61 and protrudes in the radial direction into a recess 627 in the control disk 64. At the same time, the securing element 626 lies on the inwardly facing end face 628 of the rotor 62.

A commutator 68 indispensable to the operation of the motor 650 is in a Circular bore 629 provided in the flange housing 66 pressed in such a way that the commutator 68 is flat on the side sealingly rests against the bottom 630 of the flange housing bore 629, so that additional seals are not required.

In the flange housing 66, there are also two adjacent to the commutator 68 Ring grooves 618 and 619 are formed, which are used for

Discharge of pressurized fluid are used depending on whether engine or Pump operation is desired. The commutator 68 is designed in a known manner, for example, as with the hydraulic motor that is described in the advertising brochure RD 14325 / 12.80 is described by the applicant.

The commutator 68 also takes care of it in a known manner the control disk, also known from the advertising literature mentioned, for the fact that depending on the rotation of the shaft 61 pressure medium between the rotor 62 and a displacement chambers 631 formed around the rotor 62 surrounding the ring gear 63 or is discharged from these chambers 631.

In a known manner, the rotor 62 and thus the shaft is set in rotation. To make this possible, the essentially carries heptagonal rotor on its outer circumference at each of its corners a roller 611 which cooperate with the inner circumference of the ring gear (external gear) 63. The ring gear63 has eight circular arcs of approximately the same size on its outer circumference Recesses612 and is formed in a wave-like manner on its inside that it is always in contact with all of the rollers611 attached to the rotor62. The intermediate neck 65 carries on its inner circumference eight concentric to the rotor 62 with the same distance arranged support rollers 13.

Each of these support rollers 613 works with one of the recesses 612 on the outside of the ring gear 63, the latter being eccentric with respect to the axis 625 is arranged. In the illustrated embodiment limit the rotor 62 and its rollers611 on the one hand and the ring gear63 on the other hand seven displacement chambers631 In each of which a control channel of the control disk64 opens.

As already mentioned, the basic structure and operation the commutator and the control disk64 to activate the rotor62 and the ring gear63 known from the prior art, which is why a detailed description is not given here It is important to note, however, that according to the invention, different than in the prior art the commutator, whatever shape it is in detail may have, is arranged in the flange housing66, i.e. in the housing part on the output shaft side is arranged. The housing part opposite to the flange housing63 can therefore be relatively flat in the shape of the bleeder housing 67, which only the bearing mob for the inner end of the shaft61 accommodates.

The bearing 6i0a for the output shaft side preferably extends the shaft61 not only in the area of the commutator 68, but goes furthermore (to the left in the drawing) into the flange housing 66. This is advantageous in that it results in a high bearing force absorption.

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Claims (1)

Claims 1. Rotary piston machine with an internal gear (7), with an external gear that cooperates with the internal gear and is arranged eccentrically therefrom (9), which, viewed in the axial direction, has arched bearing points (29), and with an alternately supporting the external gear on its radial outside, Seen in the axial direction 1 arcuate support points (30) having housing part (2) a multi-part housing held together by means of fastening means (25) (1 to 3), also seen in the axial direction, the bearing points of the external gear are adapted to the support points of the housing part, thereby g e k e n n z e 1 c h n e t that the bearing points of the external gear protruding radially outward Teeth (33) and the support points of the housing part are arranged in tooth recesses (34) are and that at least the outer areas of the seen in the circumferential direction Teeth of the external gear and the tooth recesses of the housing part on each other abwilzero 2. Rotary piston machine according to claim 1, characterized in that g e k e n n z e i c h -n e t that the outwardly projecting teeth (33) of the bearing points (29) External gear (9) on the outside, recesses projecting radially outward (27) for the engagement of the Innenzalinrades (7) are opposite on the inside. 3. Rotary piston machine according to one of the preceding claims, characterized characterized in that the housing (1 to 3) holding together fastening means (25) between the tooth recesses (34) having the support points (30) in which the external gear (9) surrounding housing part (2) are provided. 4. Rotary piston machine according to one of the preceding claims, characterized it is noted that the support points (30) in the housing part (2) with bearing shells are provided. 5. Rotary piston machine according to claim 4, characterized in that g e k e n n z e i c h -n e t that the bearing shell consists of a hardened material. 6. Rotary piston machine according to one of the preceding claims, characterized it is noted that, viewed in the axial direction, the support points (30) having tooth recesses (34) in the housing part (2) and bearing points (29) Teeth (33) on the outside of the external gear (9) in the shape of a circular arc over its entire circumference are trained. 7. Rotary piston machine according to one of the preceding claims, characterized it is not noted that the tooth roots of two adjacent ones, the bearing points (29) having teeth (33) on the external gear (9) arranged at a distance from one another are. 8. Displacement machine, in particular hydraulic motor with one in one Housing-mounted shaft on which a rotor and a control disc are non-rotatably arranged that work together with a ring gear and a commutator fixed to the housing, to a relative movement between the rotor corresponding to a pressure medium supply and discharge and to produce ring gear, and wherein the housing comprises flange housing means, d a d u r c h g e k e n n n z e i c h n e t that the commutator (68) rotatably in the Flange housing means is housed. 9. displacement machine, characterized in that the housing is made of a flange housing (66), an intermediate neck (65) and an end housing (67) is constructed, wherein the commutator (68) in the flange housing (66) rotatably arranged is. 10. Displacement machine according to claim 8 or 9, characterized in that that the commutator (68) is pressed into an axial bore (629) of the flange housing (66) is and on the flat side sealingly rests on the bottom (630) of the bore (629). 11. Displacement machine, characterized in that the housing parts (65,66,67klurch axially extending fastening screws (621) are connected to one another. 12. Displacement machine according to one or more of the preceding Addresses, characterized in that the mounting flange-side bearing (610a) for the shaft (fit) in the area of the commutator (68) and beyond extends into the flange housing. 13. Displacement machine according to one or more of the preceding Claims, characterized in that a securing element (626) fixed on the axial shaft is attached between control disc (64) and rotor (62). 14. Displacement machine according to claim 13, characterized in that the securing element (626) lies in a recess (627) in the control disk (64) and on the other hand rests against the flange-side end face (628) of the rotor (62). 15. Displacement machine according to one or more of the preceding Claims, characterized in that with the pressure medium inflow or the pressure medium outflow associated annular grooves 6618, 619) in the flange housing (66) adjacent to the commutator (68) are formed. 16. Displacement machine according to one or more of the preceding Claims, characterized in that the control disc (64) and rotor (62) each through Toothings (623,622) are non-rotatably connected to the shaft (61).