WO2008062023A1

WO2008062023A1 - Rotary displacement machine

Info

Publication number: WO2008062023A1
Application number: PCT/EP2007/062657
Authority: WO
Inventors: Johann Sagawe; Gottfried Sagawe
Original assignee: Johann Sagawe; Gottfried Sagawe
Priority date: 2006-11-21
Filing date: 2007-11-21
Publication date: 2008-05-29
Also published as: EP1925823A1; EP1925823B1

Abstract

A rotary displacement machine is described having a housing (1) and a first gearwheel pair (40) which has external toothing, is arranged in a working chamber (2) of the housing (1) and is formed from a working gearwheel (3) and a first conveying gearwheel (4), wherein the first conveying gearwheel (4) has a first meshing region (41) with the working gearwheel (3), wherein a first feed channel (42) for a working fluid opens into the working chamber (2) in the first meshing region (41), wherein, on that side of the first meshing region (41) which lies opposite the first feed channel (42), a first outflow channel (43) for the working fluid opens into the working chamber (2) in a region near the first meshing region (41), wherein, away from the first meshing region (41), a second conveying gearwheel (5) which has external toothing is arranged in the working chamber (2), which second conveying gearwheel (5) forms a second gearwheel pair (50), which has external toothing and a common second meshing region (51), with the working gearwheel (3), wherein, in the second meshing region (51), a second feed channel (52) for the working fluid opens into the working chamber (2), wherein, on that side of the second meshing region (51) which lies opposite the second feed channel (52), a second outflow channel (53) for the working fluid opens into the working chamber (2) in a region near the second meshing region (51), and wherein the first feed channel (42) communicates with the second outflow channel (53) in such a way that a part of the working fluid which flows into the working chamber (2) through the first feed channel (42) is transported to the second outflow channel (53) by the working gearwheel (3).

Description

description

rotary displacement

The invention relates to a Umlaufverdrängermaschine, in particular a hydraulic Außenenzahnradmotor and a hydraulic external gear pump, wherein a central Abtriebsbzw. Drive gear is provided along the circumference of a plurality of conveyor gears are arranged. The circulation displacement machine preferably has a modular construction, wherein the individual modules can be switched on as needed.

Displacement machines are hydraulic machines (pumps, motors) in which a hydrostatic power conversion takes place according to the displacement principle. In a special type of displacement machines, the rotary displacement machines, the conveying process takes place in the circumferential direction. In this case, at least two intermeshing toothed wheels are typically driven by a pressurized pressure medium (usually a fluid or working fluid) (hydraulic gear motor) or driven by an external drive (hydraulic toothed wheel pump) for delivery of the fluid.

The performance of a recirculating displacement machine, in addition to its design-related operation, in particular also determined by the pressure difference between the high-pressure and the low-pressure zone of the machine. By increasing the pressure or the torque, the performance of the respective application can be adjusted. However, the maximum power of a gear machine is limited primarily by the load capacity of the machine parts involved. Excessive load on these parts can destroy the machine. Since it is not possible in the example operated as a gear motor conventional Umlaufverdrängermaschine, the performance through Increasing the fluid pressure to increase arbitrarily, the machine must be sized accordingly large to achieve a higher performance.

The object of the invention is to provide a circulation displacement machine with a high performance. It is another object of the invention to provide a Umlaufverdrängermaschine that allows flexible use. This object is achieved by a circulation displacement machine according to claim 1. Furthermore, the invention is achieved by a housing according to claim 19 and an external gear according to claim 21. Further advantageous embodiments of the invention are specified in the dependent claims.

According to the invention, there is provided a recirculating displacement machine having a housing and a first external gear pair disposed in a working chamber of the housing, the gear pair being formed of a work gear and a first feed gear. The first conveying gear has a first combing area together with the working gear. Furthermore, a first supply channel for a working fluid is provided, which opens into the working chamber in a region near the first combing region. On the side of the first combing area opposite the first inlet channel, a first outlet channel for the working fluid also opens into the working chamber in a region near the first combing area. It is envisaged that, apart from the first combing area, a second externally toothed conveying gear wheel is arranged in the working chamber, which with the work gear forms a second externally toothed gear pair with a common second combing area. In this case, a second inlet channel for the working fluid opens into the working chamber in a region near the second combing region, while a second outlet channel for the working fluid opens into the working chamber in a region near the second combing region on the side of the second combing region opposite the second inlet channel. The first inflow channel and the second inflow channel are fluidly connected in this way. connected to each other that a part of the flowing through the first inlet channel in the working chamber working fluid is transported from the working gear to the second outlet channel in the intended operation of the rotary displacement. In this particular arrangement of the gears, the two pairs of gears each formed from a conveyor gear and the working gear form two hydraulic machines interacting with each other. The use of a common drive gear allows the hydraulic machines to be coupled, thereby increasing the performance of the entire recirculating displacement machine. Furthermore, the use of a common drive gear also leads to material savings and weight reduction, since only a single work gear and a single housing is necessary. Since only one drive or output shaft also has to be led out of the housing, this arrangement also requires only an elaborate seal for the corresponding shaft.

In an advantageous embodiment of the invention, it is provided that a third externally toothed conveyor gear is arranged in the working chamber, which forms with the work gear a third gear pair with a common third combing area. In this case, a third inlet channel for the working fluid in the combing area opens into the working chamber, while a third outlet channel for the working fluid opens into the working chamber on the side of the third combing area opposite the third inlet channel. The second inlet channel and the third outlet channel communicate fluidically with one another in such a way that a portion of the working fluid flowing into the working chamber through the second inlet channel is transported from the working gear to the third outlet channel. By the third conveyor gear, the performance of Umlaufverdrängermaschine can be further increased.

In a further advantageous embodiment of the invention, the work gear is formed as a central gear, along the circumference at least three conveyor gears ange- which mesh with the working gear. In particular, by a uniform distribution of the conveyor gears along the circumference of the drive gear uniform loading of the drive gear and the drive shaft can be achieved. This has a positive effect on the service life of the machine.

In a further advantageous embodiment of the invention it is provided that the working gear has a same or a smaller diameter than the conveyor gears. In particular, by using conveyor gears with relatively large diameters, the speed of these gears can be reduced. This results in a quieter run. Furthermore, the larger conveyor gears can also produce greater torque.

A further advantageous embodiment of the invention provides that the working gear has a substantially larger diameter than the conveyor gears. On the one hand, this allows a plurality of conveyor gears along the circumference of the drive gear can be arranged, whereby a relatively high performance can be achieved. On the other hand, this allows a better sealing of the drive shaft, since this shaft is located farther away from the high-pressure regions formed in the mouth regions of the inlet channels of the individual toothed wheel pairs due to the relatively large diameter of the working toothed wheel.

In a further advantageous embodiment of the invention, it is provided that the feed channel assigned to a gear pair opens onto the combing area of the respective gear pair and opens into the working chamber. As a result, a favorable supply of the working fluid is achieved in the working chamber. It is further provided that the mouth opening of the feed pair associated with a gear pair is arranged in the bottom surface of the working chamber. Due to the different arrangement of the inlet and the drain channels, the Conveyor gears are placed close to each other without their inlet and outlet channels interfere with each other. The arrangement of the flow channel in the bottom surface of the working chamber immediately at the edge of the combing area proves to be favorable for the flow of the working fluid.

Furthermore, a particularly advantageous embodiment of the invention provides that a screen element is arranged on the side of a combing region facing the inlet channel. This shielding element makes it possible to shield the combing area from the working fluid flowing into the working chamber. As a result, disturbing turbulence can be avoided, which typically arise due to the rotation of the gears in the flowing fluid.

In a further advantageous embodiment of the invention, it is provided that the shielding element has a vertical impact surface for the working fluid. The use of such a baffle surface allows advantageous guidance of the flowing working fluid.

A particularly advantageous embodiment of the invention provides that the shield element has a wedge-shaped region which engages between the feed gear and the working gear wheel. As a result, the associated combing area can be shielded particularly effectively from the incoming working fluid. The working fluid only reaches the interdental spaces of the rotating toothed wheels in the regions not covered by the shielding element. This avoids turbulence and favors the flow of the working fluid. In particular, by reducing turbulence, the efficiency of the machine can be improved.

In a further advantageous embodiment of the invention it is provided that the teeth of the conveyor gears have a reduced compared to the teeth of the working gear in the operation of the machine as a motor height, which by the ge Genendes engagement of the teeth of the feed gear and the work gear in the interdental spaces of the work gear residual volume formed is increased. The increased residual volume makes it possible to return part of the working fluid from the discharge channel via the combing area to the inlet channel. As a result, the fluid consumption of the gear motor can be reduced. Furthermore, the speed of the engine can be increased in this way.

Furthermore, it is provided in an advantageous embodiment of the invention that in the interdental spaces of a conveyor gear each have a depression in the tooth bottom is formed. As a result, the residual volume remaining in the tooth spaces of the work gear due to the mutual engagement of the teeth of the feed gear and the work gear is increased. As a result, the fluid consumption of the gear motor can be further reduced. Furthermore, the speed of the engine can be increased with constant working fluid consumption. This advantageous effect can be further enhanced even if the teeth of the conveyor gears have a recess in their head areas.

In a further advantageous embodiment of the invention it is provided that the housing is modular, wherein a module comprises a conveyor gear, which forms a pair of gears with a common Kämmbereich together with the working gear. The modular design allows flexible use of the machine. As needed, more or less modules can be provided whereby the performance of the machine can be adapted to the particular application.

Finally, a further advantageous embodiment of the invention provides that a module of the rotary displacement machine can be switched on and off separately in order to set a desired power. As a result, the performance of the machine can be adapted without modification of the respective application. In the following the invention will be explained in more detail with reference to drawings. Show it:

Figure 1 shows a Umlaufverdrängermaschine invention with a central working gear and three arranged along the circumference of the work gear conveyor gears.

FIG. 2 shows a housing of the rotary displacement machine according to the invention with an inner working chamber; FIG.

3 shows an inventive conveyor gear for a rotary displacement machine;

4A and 4B show two variants of a further embodiment of the rotary displacement machine according to the invention with four symmetrically arranged around a central drive gear conveyor gears and a modular housing.

Fig. 5 shows a further embodiment of the rotary displacement machine according to the invention with three symmetrically arranged around a small drive gear conveyor gears; and

6 is a perspective view of a conveyor gear according to the invention for a rotary displacement machine.

FIG. 1 shows by way of example the structure of a rotary displacement machine according to the invention. Such a rotary displacement machine, such as a hydraulic gear motor or a hydraulic gear pump, has a housing 1. Inside the housing 1, a working chamber 2 for receiving a plurality of external gears is formed. The working chamber 2 forms a closed fluid space which is decoupled from the environment by the housing wall. It is formed by cylindrical recesses in the housing 1, which serve as sub-chambers for receiving a respective gear. In the present embodiment of the invention are in the working chamber 2 four intermeshing external gears 3,4,5,6 arranged. These are preferably by means of appropriate bearings, such as sliding or rolling bearings, rotatably mounted in the housing 1 of the machine. A first external gear 3 forms a central working gear, which is connected to a shaft 31. The preferably guided by the housing 1 to the outside shaft 31 serves to transmit the torque between the hydraulic machine and the environment. In the machine operated as a gear motor, the torque generated by the fluid pressure in the hydraulic machine is tapped off via this shaft 31 serving as the output shaft. On the other hand, in the rotary displacement machine operated as a gear pump, the internal external gears 3, 4, 5, 6 are driven via this shaft 31, which serves as the drive shaft, in order to achieve delivery of the working fluid.

The three other housed in the working chamber 2 outer gears 4,5,6 are arranged along the circumference of the working gear 3. They serve as conveyor gears which, together with the working gear 3, each form a gear pair 40, 50, 60. Each of the pairs of gears formed by a feed gear 4,5,6 and the drive gear 3 is an independent motor or pump unit. For this purpose, each of the three externally toothed conveyor gears 4,5,6 a common combing 41,51,61 with the central working gear 3 on. The combing area of two external gears is that region in which the teeth of the involved gears come into mutual engagement. It essentially corresponds to the overlapping area of the head circles of the involved gears.

The working gear 3 and the three conveyor gears 4,5,6 are each arranged individually rotatably mounted in the sub-chambers 23,24,25,26 of the working chamber 2. To see a leakage between the side wall of a sub-chamber 23,24,25,26 and the

To prevent teeth of the associated external gear 3,4,5,6, which adversely affect the efficiency of the Umlaufverdrängerma- machine, the diameters of the preferably circular subchambers are essentially adapted to the tip circle diameters of the respective toothed wheels. Preferably, each external gear 3,4,5,6 is tightly enclosed by a part of the housing inner wall over a substantial part of its circumference.

Each pair of gears 40,50,60 has its own inlet channel 42,52,62 and a separate outlet channel 43,53,63, which open respectively on opposite sides of the respective combing 41,51,61 in the working chamber 2. In the case of the machine operated as a gear motor, the working fluid under high pressure is fed into the working chamber 2 via the high-pressure-side inlet channel 42, 52, 62. On the other hand, the working fluid transported by the respective conveyor gear and the working gear 3 to the mouth region of the respective discharge channel 43, 53, 63 leaves the working chamber 2 via the low-pressure-side discharge channel 43, 53, 63. The inlet channel 42, 52, 62 is preferably arranged on the front side of the toothed wheels, so that its mouth is formed in the side wall of the working chamber 2. As shown in FIG. 1, an inlet channel 42, 52, 62 is directed toward the associated combing area 41, 51, 61. In contrast to this, the mouth of the associated outflow channel 43, 53, 63 arranged on the side of the combing region 41, 51, 61 opposite the inlet channel 42, 52, 62 is formed in a bottom surface of the working chamber 2. As a result of this arrangement of the discharge channel 43, 53, 63, the side wall in the transition between the first sub-chamber 23 and the conveying gear sub-chambers 24, 25, 26 can be made particularly streamlined. A corresponding rounding of this part of the side wall is shown in FIG. Moreover, it is advantageous if the Ablaufka- nalmündung arranged directly on the edge of Kämmbereichs 41,51,61 or even partially protrudes into the Kämmbereich 41,51,61, since this by the mutual engagement of the teeth of the respective gear pair 40,50 , 60 from the tooth Interspaces displaced working fluid can flow directly into the respective outlet channel 43,53,63.

The arrangement of the channels 42,43,52,53,62,63 shown in Figure 1 allows a relatively small mutual distance of the conveyor gears 4,5,6 along the circumference of the working gear 3, since the drain and the inlet channels 42, 43,52,53,62,63 of adjacent conveyor gears 4,5,6 do not interfere with each other. This makes it possible to arrange a relatively high number of conveyor gears along the circumference of the working gear 3. Furthermore, a close arrangement of the conveyor gears allows 4,5,6 on only one side of the working gear 3, a relatively compact machine housing 1 produce.

Each channel 42,43,52,53,62,63 is preferably connected to its own arranged on the outside of the housing 1 connection. The serving as inputs or outputs for the working fluid connections are usually designed to be connected to special hydraulic lines. However, several of the running in the housing 1 Zulaufbzw. Flow channels 42,43,52,53,62,63 also share a common input and output. As a result, the number of connections required on the machine housing 1 can be reduced.

As shown in FIG. 1, the three conveying gears 4, 5, 6, 6 are preferably arranged substantially uniformly along the circumference of the external gear 3. This uniform arrangement of the conveyor gear wheels 4, 5, 6 enables a more uniform loading of the bearings of the external gear 3, whereby advantageously a calmer and easier running of the external gear 3 and a lesser wear of the loaded parts can be achieved. However, a uniform distribution of the conveyor gears 4,5,6 along the Außenzahnradumfangs is not absolutely necessary. In order to obtain a more compact machine housing 1, it may be useful to have the conveyor gears 4, 5, 6 only on one side of the outer tooth. Rads 3 as close to each other to arrange. Advantageously, by relatively simple conversion measures, in particular by the installation or removal of individual conveyor gears 4,5,6, the number and the distribution of the conveyor gears 4,5,6 along the circumference of the working gear 3 are adapted to the respective needs.

The size or diameter of the gears used may vary. In a machine having a relatively large work gear 3, it is possible to arrange a larger number of relatively small feed gears 4, 5, 6 along the outer circumference of the work gear 3. By contrast, by using relatively large conveyor gears 4, 5, 6 and a working gear 3 having a relatively small diameter, the power of the individual conveyor gears 4, 5, 6 can be increased.

By providing the same size gears 3,4,5,6 turn the manufacturing cost of the machine can be reduced.

The conveyor gears 4, 5, 6 of the circulatory displacement machine shown in FIG. 1 are preferably mounted on a non-rotating shaft 45, 55, 65 by means of an inner bearing. By the e.g. formed as part of the housing 1 shaft 45,55,65 a particularly simple and quick installation of the conveyor gears 4,5,6 allows. This is particularly advantageous if the recirculating displacement machine is converted for a special application and at least one feed gear 4,5,6 is to be inserted into an already existing sub-chamber 24,25,26 or removed from the corresponding sub-chamber 24,25,26 , However, assembly of the conveyor gears 4, 5, 6 is also possible with a rotating shaft fixedly connected to the respective conveyor gear 4, 5, 6 (not shown here).

Since the drive gear 3 preferably has a relatively large diameter, the drive shaft 31 connected to the axis of the work gear 3 is relatively far away from the high pressure areas arranged on its outer circumference. In particular, with relatively small gaps between the drive gear 3 and the housing inner wall, an additional decoupling of the drive shaft 31 can be achieved by the high pressure areas. Thus, the working fluid with the full inlet pressure is prevented from acting on the seal of the drive shaft 31.

The conveyor gears 4, 5, 6 of the rotary displacement machine shown in FIG. 1 have teeth with a reduced height. By means of such half-gears it is necessary to reduce the fluid consumption of the rotary displacement machine operated as a geared motor. In the mutual engagement of the teeth of the working gear 3 and the respective conveyor gear 4,5,6 not the entire existing in the interdental spaces of the work gear 3 working fluid is displaced. Through the use of half teeth thus remaining in the interdental spaces of the working gear 3 residual volume is increased. The working fluid remaining in this residual volume is transported back to the respective inlet channel 42, 52, 62 via the respective combing area 41, 51, 61. Compared to a full-circumferential rotary displacement machine, by using the half teeth at the same speed, the necessary flow rate of the working fluid can be reduced.

The circulation displacement machine according to the invention can also be operated as an external gear pump. Here, the two externally toothed gears of a gear pair each form an independent pump unit. As a result of the rotation of the gearwheels, the pressure medium on the pressure side (outflow side) is pressed out of the tooth spaces, while the suction pressure (on the supply side) results in the vacuum necessary to draw in the working fluid. However, it makes sense to operate the circulation displacement machine shown in the figure 1 preferably only as a gear motor. Due to the increased return volume over the combing areas 41, 51, 61 of the three gear pairs 40, 50, 60, this machine can be used as a gear pump in operation. achieve a low efficiency. In order to operate the recirculating displacement machine according to the invention as a gear pump, provided with full teeth conveyor gears is to be used. Here, the working fluid is almost completely displaced from the interdental spaces of the work gear during mutual meshing of the gears involved. This alternative Umlaufverdrängermaschine is not shown in the figures.

The circulation displacement machine according to the invention can be modular. In this case, a typical module preferably in each case comprises a conveyor gear wheel. In principle, the modules can also comprise a plurality of conveyor gears. Furthermore, it is also possible to provide modules which have no conveyor gears and corresponding sub-chambers. Such replacement modules can replace unneeded modules with conveyor gears. Preferably, a replacement module is designed so that the work gear is tightly enclosed by the housing wall in this area. The replacement modules can prevent turbulence and thus achieve higher efficiencies.

By exchanging and combining the various modules, any configuration of a machine can be produced. In particular, this allows the number, distribution and

Change the size of the conveyor gears of the machine. This makes it possible to build the machine to the respective power requirements. This allows a flexible use of Umlaufverdrängermaschine invention.

The performance of the rotary displacement machine can also be adjusted as required during operation by selectively switching off and on the individual conveyor gears or modules. The shutdown of a conveyor gear can for example take place in that the inlet and the outlet channel of the respective conveyor gear are decoupled from the hydraulic circuit and short-circuited with each other. This is NEN inlet channel of an adjacent conveyor gear in the working chamber 2 supplied and transported from the drive gear 3 to the shut-off conveyor gear working fluid is transported in this case only partially along the circumference of the co-rotating conveyor gear. The other part of the working fluid is forwarded via the newly created bypass connection between the drainage channel and the inlet channel of the respective conveyor gearwheel, without the respective conveyor gear wheel being driven in or being conveyed by this conveyor gearwheel. The selective connection and disconnection of the conveyor gears can in principle also be realized in a rotary displacement machine which has a modular design. In this case, entire modules can be bridged via corresponding bypass lines.

FIG. 2 shows the housing 1 of the rotary displacement machine according to the invention. Preferably made of a metal such as e.g. Aluminum, or a metal alloy existing housing block 1 is usually composed of plates together. Inside the housing block 1, the trained for receiving the gears working chamber 2 is arranged. It is completely isolated from the environment by the housing 1. As shown in FIG. 2, the working chamber 2 comprises four contiguous sub-chambers 23, 24, 25, 26, which are preferably designed as cylindrical recesses with circular base surfaces. Each sub-chamber 23,24,25,26 is formed for receiving a respective gear 3,4,5,6. The central recess forms a first sub-chamber 23, which is provided for receiving the central working gear 3. It has a relatively large diameter. Along the circumference of this sub-chamber 23, three further sub-chambers 24,25,26 are arranged with a smaller diameter, which are provided for receiving a conveyor gear. Each of the three further sub-chambers 24, 25, 26 has its own overlap area 241, 251, 261 with the first sub-chamber 23, which in FIG

Essentially due to the mutual dentition handle of the associated gears formed combing 41,51,61 corresponds.

To rotatably support the work gear 3 in the first sub-chamber 23, a first bore 231 is provided in the center of the bottom surface of the first sub-chamber 23. This bore 231 is designed to receive the axis of the working gear 3 and preferably dimensioned so that they can also accommodate an associated ball bearing in addition to the actual axis. In the opposite bottom surface of the first sub-chamber 23, a second bore corresponding to the first bore 231 is provided, which is likewise designed to receive the axis of the working gear 3 (this bore is not shown here). While the first bore 231 is preferably formed as a continuous bore and serves to lead out the connected to the axis of the working gear 3 shaft 31 out of the housing 1, the second bore is preferably formed as a blind hole. If the shaft 31 is to be executed on one side only from the housing block 1, the sealing of the shaft 31 can thus be simplified.

In the housing block 1 special holes 42,43,52,53,62,63 are provided, which serve as inlet or outlet channels for the working fluid. The mouth openings of these channels

42, 43, 52, 53, 62, 63 are arranged directly in the vicinity of the overlapping regions 241, 251, 261 of the subcompartments 23, 24, 25, 26, the inlet channels 42, 52, 62 being arranged on the respective flow channels 43, 53, 63 opposite side of the associated overlap region 241,251,261 open into the working chamber 2. The channels 42,43,52,53,62,63 lead out of the housing block 1 and are preferably connected to inputs and outputs for the working fluid. The inputs and outputs are formed as attached to the outside of the housing block 1 connections, which are preferably provided for the connection of special hydraulic lines. The channels 42, 52, 62, 43, 53, 63 preferably run in the housing block 1 in such a way that the inlet channel 42, 52, 62 assigned to a specific conveyor gear part chamber 24, 25, 26 and the immediately adjacent outlet channel 43, 53, 63 of a neighboring Förderzahnradteilkammer 26,24,25 do not interfere with each other. As shown in FIG. 2, each inlet channel 42, 52, 62 extends laterally out of the housing block 1, while the corresponding outlet channel 43, 53, 63 runs preferably obliquely in the housing block 1, at least in its first section.

In order to prevent disturbing turbulences and thus to favorably influence the flow of the working fluid in the mouth region of a feed channel 42, 52, 62, shielding elements 44, 54, 64 can be provided, which provide the associated combing region

41.51,61 of the respective inlet channel 42,52,62 shield. Such a screen element 44,54,64 preferably has a vertical baffle 441,541,641 for the working fluid. Furthermore, the shield element 44, 54, 64 preferably has a wedge-shaped region 442, 542, 622, which engages between the corresponding subchambers 23, 24, 25, 26 and may extend as far as the intersecting region 241, 251, 261 of these subchambers 23, 24, 25, 26. In order to achieve a better sealing of the combing area in relation to the inlet channel 42, 52, 62, the wedge-shaped area 442, 542, 622 is preferably adapted to the contour of the respective partial chambers 23, 24, 25, 26.

In order to reduce the fluid consumption of the circulatory displacement machine operated as a geared motor, the residual volume remaining in the interdental spaces when the teeth of a gearwheel pair engage each other can be increased by suitable measures. 3 shows a specially designed external gear 8 with half teeth, with the aid of which a corresponding circulation displacement machine can be realized with a higher return volume. Such a half gear is preferably used as a feed gear 4,5,6 in the rotary displacement machine shown in Figure 1. The Half gear 8 has special recesses 81 in the bottom surfaces of the interdental spaces, which are preferably cone-shaped or wedge-shaped. By means of these recesses 81, the remaining volume remaining in the inter-engagement of the teeth of the feed gear and the work gear in the interdental spaces of the feed gear can be significantly increased. On the other hand, an increase in the residual volume formed in the mutual engagement of the teeth in the interdental spaces of the working gear 3 can be increased by means of special depressions 82 in the head regions of the conveying gear 4, 5, 6. Both types of depressions 81, 82 can be realized both jointly and individually. In order to avoid material damage, the recesses 81, 82 should always be designed in such a way that the teeth still have sufficient load capacity.

FIGS. 4A and 4B show further exemplary embodiments of the rotary displacement machine according to the invention. In this case, the machine shown schematically in FIG. 4A has four conveyor gears 4, 5, 6, 7, which are arranged symmetrically about the central work gear 3. The symmetrical arrangement of the conveyor gears 4,5,6,7 allows a particularly uniform loading of the working gear 3 and the associated bearings. Each of the four conveyor gears 4,5,6,7 forms with the central working gear 3 has its own combing, each associated with an inlet and an outlet channel.

In the present example, the housing 1 of the machine has a contour essentially predetermined by the inner working chamber 3. The resulting housing 1 has a substantially square shape with rounded corners. This form proves to be particularly space-saving. Basically, however, since housing can have any shape.

Furthermore, the housing 1 of the rotary displacement machine shown in FIG. 4A has a modular construction. there is in the lower part of the machine, a base module 90 is provided that includes two conveyor gears 5.6 and the associated sub-chambers. In the upper part of the machine, however, two individual modules 91,92, each with a conveyor gear 3,7 and the associated sub-chamber are provided. Within the individual modules 90,91,92 preferably also the channels are provided, which are assigned to the respective conveyor gears 4,5,6,7. The working gear 3 and the associated sub-chamber can be part of the base module 90. Due to the modular construction, it is possible to change the configuration of the machine, and in particular the number and distribution of the feed gears along the circumference of the work gear 3.

Such a changed configuration of the machine is shown in FIG. 4B. In this case, a single module 92, which contains a conveyor gear 7 and the corresponding sub-chamber, was replaced by a new module 93 without a feed gear and the associated sub-chamber. The new module 93 is preferably designed so that it closely encloses the work gear 3. As a result, turbulence can be prevented, which can be caused by the fact that a conveyor gear only removed from its sub-chamber for the purpose of configuration of the machine, or e.g. is bypassed by means of a bypass.

FIG. 5 shows, on the basis of a further exemplary embodiment, the interior of a rotary displacement machine which has three conveyor gears 4, 5, 6 arranged symmetrically about a central drive gear 3. The central drive gear 3 in this case has a smaller diameter than the three outer conveyor gears 4,5,6. As a result, a favorable transmission ratio can be achieved, in particular during operation as a motor. Further, in motor operation by using half-gear wheels remaining in the interdental spaces of the work gear 3 remaining volume can be increased. A further increase in the residual volume can also be through appropriate depressions in the interdental spaces and in the tooth tips the individual conveyor gears are 4,5,6 increased. For simplicity, these recesses are shown in Figure 5 only a few teeth of the conveyor gears 4,5,6. Through the recesses in the interdental spaces and in the tooth tip regions of the conveyor gears 4,5,6 and a larger work area is reached, which is the pressure medium as a target surface available. As a result, a larger torque, a greater power transmission and thus an improved efficiency of the engine can be achieved.

Also, between the individual teeth of the drive gear 3 corresponding recesses may be provided by which both the residual volume and the pressure medium available attack surface can be increased. To simplify a corresponding depression is shown in the figure 5 only between the two teeth of the drive gear 3, which are currently in engagement with the teeth of the first conveyor gear 4.

Arrows indicate the liquid flow in FIG. 5. As can be seen, the fluid is distributed by the arranged at each of the inflow screen element to the corresponding gears. The screen elements likewise shown in FIG. 5 cause a reduction of turbulences and thus a better liquid distribution. This makes it easier to start the engine.

6 shows a meshing with a drive gear 3 conveyor gear 8. While the teeth of the drive gear 3, full height, the teeth of the conveyor gear 8 are formed as half-teeth. This is indicated by corresponding pitch circle diameter. As can be seen in FIG. 6, the conical or wedge-shaped depressions 81, 82 in the head region of a semi-tooth and in the spaces between the teeth each form a groove extending over the entire width of the conveyor gearwheel 8. For better illustration of these grooves 81,82 two half-teeth are shown in a perspective view. It can also be seen here that additional working surfaces 83, 84, which serve as a contact surface for the pressure medium, were created by the depressions 81, 82. As can be seen in FIG. 6, the two meshing gears 3, 8 can be designed such that two dense surfaces are formed. As a result, the radial seal can be improved, resulting in less leakage.

Claims

claims

1. Circulating displacement machine comprising a housing (1) and a first externally toothed gear pair (40) arranged in a working chamber (2) of the housing (1), comprising a work gear (3) and a first combing area with the work gear (3) (41) having first conveying gear (4) is formed, wherein in the first combing region (41) a first inlet channel (42) for a working fluid in the working chamber (2) opens, and wherein on the first inlet channel (42) opposite side of the first Combination area (41) a first discharge passage (43) for the working fluid in the working chamber (2) opens, characterized in that a second external geared Förderzahnrad (5) in the working chamber (2) is arranged, with the working gear (3) a second gear pair (50) with a common second combing area (51), wherein a second feed channel (52) for the working fluid in the second combing area (51) opens into the working chamber (2), wherein au f of the second inlet channel (52) opposite side of the second Kämmbereichs (51), a second outlet channel (53) for the working fluid in the working chamber (2) opens, and wherein the first inlet channel (42) in such a way with the second drain channel (53 ) fluidically communicates that a part of the working fluid flowing through the first inlet channel (42) into the working chamber (2) is transported from the working gear (3) to the second outlet channel (53).

2. rotary displacement machine according to claim 1, characterized in that a third external toothed conveyor gear (6) in the working chamber (2) is arranged, with the working gear (3) a third gear pair (60) with a common third Kämmbereich (61) forms, wherein in the third Kämmbereich (61) a third feed channel (62) for the working fluid in the working chamber (2) opens, wherein a third outlet channel (63) for the working fluid opens into the working chamber (2) on the side of the third combing area (61) opposite the third inlet channel (62), and wherein the second inlet channel (52) is connected to the third outlet channel (51). 63) communicates fluidically that a part of the working fluid flowing into the working chamber (2) through the second inlet channel (52) is transported from the working gear (3) to the third outlet channel (63).

3. rotary displacement machine according to claim 1 or 2, d a d u r c h e c e n e c e s in that the work gear (3) is designed as a central gear along the circumference at least three conveyor gears (4,5,6) are arranged, which mesh with the working gear (3).

4. A rotary displacement machine according to one of the preceding claims, characterized in that the working gear (3) has the same or a smaller diameter than the conveyor gears (4,5,6).

5. A rotary displacement machine according to one of the preceding claims, characterized in that the working gear (3) has a substantially larger diameter than the conveyor gears (4,5,6).

6. Umlaufverdrängermaschine according to any one of the preceding arrival claims, characterized in that the gear pair (40,50,60) associated with inlet channel (42,52,62) on the combing (41,51,61) of the gear pair (40,50, 60) directed into the working chamber (2) opens.

7. circulation displacement machine according to claim 6, characterized in that the mouth of the inlet channel (42, 52, 62) associated with a gear pair (40, 50, 60) is formed in the bottom surface of the working chamber (2).

8. circulating displacement machine according to claim 6 or 7, d a d u r c h e c e n e c e s in that a screen element (44,54,64) is arranged on the inlet channel (42,52,62) facing side of a combing area (41,51,61).

9. Circulating displacement machine according to claim 8, characterized in that the screen element (44, 54, 64) has a vertical baffle surface

(441.541.641) for the working fluid.

10. Circulating displacement machine according to claim 8 or 9, characterized in that the screen element (44, 54, 64) has a wedge-shaped area

(442.542.642) which engages between the feed gear (4, 5, 6) and the drive gear (3).

11. The rotary displacement machine according to claim 1, wherein the rotary displacement machine is designed so that a conveyor gear can be separately switched on and off to set a desired power.

12. A rotary displacement machine according to one of the preceding claims, characterized in that the circulation displacement machine operates as a gear pump.

13. Umlaufverdrängermaschine according to any one of the preceding claims, characterized in that the Umlaufverdrängermaschine works as a gear motor.

14. rotary displacement machine according to claim 13, characterized in that the teeth of the conveyor gears (4,5,6) have a relation to the teeth of the working gear (3) reduced height, wherein the by the mutual engagement of the teeth of the conveyor gear (4,5, 6) and the working gear (3) in the interdental spaces of the working gear (3) residual volume formed is increased.

15. Circulating displacement machine according to one of claims 13 or 14, characterized in that in the interdental spaces of a conveyor gear (4,5,6) each have a recess in the tooth bottom is provided, through which the mutual engagement of the teeth of the conveyor gear (4,5,6 ) and the working gear (3) in the interdental spaces of the conveyor gear (4,5,6) formed residual volume is increased.

16. A rotary displacement machine according to one of claims 13 to 15, characterized in that the teeth of the conveyor gears (4,5,6) in their Kopfbe- rich () have a recess through which in the mutual engagement of the teeth of the conveyor gear (4,5 , 6) and the working gear (3) in the interdental spaces of the working gear (3) residual volume formed is increased.

17. Circulating displacement machine according to one of the preceding claims, characterized in that the housing (1) is modular, wherein a module comprises a conveyor gear (4,5,6), which together with the work gear (3) a pair of gears (40, 50,60) with a common combing area (41,51,61) forms.

18. A rotary displacement machine according to claim 17, wherein a module of the rotary displacement machine can be separately switched on and off in order to set a desired power.

19. Housing for a rotary displacement machine, comprising a working chamber (2) with a first sub-chamber (23) which is adapted to receive an externally toothed working gear (3), and a second sub-chamber (24) for receiving a first externally toothed conveying gear ( 4), wherein the first and the second sub-chamber (23,24) have a common first intersection region (241), wherein the first sub-chamber (23) has a through bore for receiving a shaft (31) connected to the work gear (3). and wherein in the first overlap region (241) a first feed channel (42) for a working fluid opens into the working chamber (2), and wherein on the first feed channel (42) opposite side of the first overlap region (241), a first discharge channel (43 ) for the working fluid into the working chamber (2), characterized in that the working chamber (2) has at least one further sub-chamber (25,26) t, which is designed to receive a further externally toothed conveying gear (5, 6), wherein the first and the further subchambers (23, 25, 26) together have a further overlapping area (251, 261), wherein in the further overlapping area (251, 261) another feed channel (52, 62) for a working fluid opens into the working chamber (2), and wherein on the side of the further overlapping region (251, 261) opposite the further feed channel (52, 62) another outlet channel (53, 63) for the working fluid opens into the working chamber (2).

20. Housing according to claim 19, characterized in that the partial chambers (24, 25, 26) provided for receiving the conveyor gear wheels (4, 5, 6) are arranged substantially uniformly along the circumference of the first sub-chamber (23).

21 external gear for a Umlaufverdrängerkaschine, characterized in that the teeth of the external gear (8) have a reduced height, wherein in the interdental spaces of the external gear (8) each have a recess (81) is provided in the tooth base through which the mutual engagement of the teeth the external gear (8) and a further external gear (8) in the interdental spaces of the external gear (8) formed residual volume is increased.

22, external gear according to claim 21, characterized in that the teeth of the external gear (8) in their head regions () have a recess (82) through which in the mutual engagement of the teeth of the external gear (8) and the further external gear (8) in the interdental spaces of the further external gear (8) formed residual volume is increased.