AT502908B1 - HYDRAULIC GEARBOX - Google Patents

Description

1 1 2 AT 502 908 B1

The invention relates to a hydraulic transmission with harmonious transition of the pressure medium between two trained as a cell rotor displacement machines, with a radially displaceable first displacement body having first impeller and a radially displaceable second displacement body having second impeller, wherein the first impeller 5 is disposed within the second impeller and the first displacement body of the first impeller along a cylindrical tread of the surrounding second impeller are guided and between the two wheels at least a first working space and a second working space between the second impeller and a surrounding guide body is formed, wherein the second impeller at least one radial connection channel to Strö -io mungsverbindung the first and the second working spaces has.

From US 2,434,546 A, a hydraulic transmission with two vane-cell machines is known. Between an inner vane wheel and an eccentric rotor first displacement chambers are formed, wherein pressure is built up by the inner vane wheel impeller. Second displacement chambers are formed between the outer surface of the rotor and a cylindrical housing, wherein the housing has on its inside radially displaceable blades, which are run over by the eccentrically mounted rotor. Via connecting slots in the rotor, the first displacement chambers communicate with the second displacement chambers. As a result, pressure differences in the two-20 th displacement chambers can be built, which generate a torque on the rotor. The axis of the rotor is displaceably arranged with respect to the inner Flügelzellenlaufrades and the outer housing, wherein the rotational direction of the rotor can be reversed by adjusting the axis of rotation of the rotor from a first position in a respect to the axis of rotation of the Flügelzellenlaufrades diametrically opposite second position. The disadvantage is that 25 large imbalances caused by the eccentric rotor, which balance weights are required. This increases the production cost and increases the volume and weight of the transmission. A similar hydraulic transmission is also known from DE 196 26 13 A. From GB 400 862 B a hydraulic transmission with roller cell machines is known which utilizes an externally driven roller cell pump which drives another roller cell machine arranged adjacent thereto. The rollers are in each case arranged in radial recesses of the wheels and radially displaceable, so that displacement spaces arise with different pressures upon rotation of the wheels. The disadvantage is that the device 35 has a relatively high volume.

US 4,793,138 A discloses a hydrostatic transmission with two roller-cell machines with an inner impeller and an outer impeller, wherein a rotatable control ring is arranged between the two impellers. At the inner or outer circumferential surface of the control-40 ring run the cell rollers of the inner and outer impeller to. The control ring has different thickness and opposite eccentricities, so that by rotation of the ring, the displacement of the displacement chambers of the two roller cell machines can be changed. With this gear, the speed and the direction of rotation of the driven impeller can be changed. A torque control is not provided. 45

From JP 06-280967 A, a hydraulic transmission of the type mentioned is known in which by adjusting the guide body, the speed of the motor operated as an outer impeller can be varied only to a small extent at a constant flow rate of the pump formed by the inner impeller. A change in the direction of rotation of the motor so with constant drive of the pump under load could - if at all - be achieved only under strong efficiency losses. Furthermore, it is disadvantageous that the absorption volume of the pump rotor can not be changed. This means that regardless of the power flow, all the hydraulic fluid must be pumped, which also contributes to poor efficiency. 55 3 AT 502 908 B1

From GB 205 815 A, it is known in a hydraulic transmission, an impeller and a guide body rotatably connected to each other perform, with displacement bodies on the outside of the impeller pivotally and on the inside of the guide body both radially displaceable, and pivotally guided. 5

The object of the invention is to avoid the disadvantages mentioned, and to provide a hydraulic transmission of the type mentioned, which is replaceable in a wide operating range with good efficiency. According to the invention this is achieved in that the second impeller and the guide body are rotatably connected to each other and that the second displacement body are guided on the outside of the second impeller and / or on the inside of the guide body radially displaceable and / or pivotable. The rotary connection between the second impeller and the guide body takes place, for example, via a journal slot connection between the second impeller and the guide body, wherein a plurality of pins are preferably arranged on the rim of the second impeller, which engage in corresponding oblong holes of the guide body. The fact that the second impeller is rotationally connected to the guide body, friction losses can be reduced and the efficiency can be increased.

It is preferably provided that each second displacement body is arranged at one end both radially displaceable, and pivotable in a radial recess of the second impeller 25 or the guide body and at the other end immovable but pivotable in a radial recess of the guide body and the second impeller.

Each second displacement body may have at a first end a first cylindrical thickening, via which the displacement body is pivotably mounted in a preferably cylindrical recess of the guide body or the second impeller.

According to one embodiment variant of the invention, it can be provided that the second displacement body also has at least one second end a preferably cylindrical second thickening over which the second displacement body in a recess 35 of the second impeller or the guide body both radially displaceable, as well as pivotable is stored. Alternatively, it is also possible that the second displacement body is mounted on at least one end radially displaceable in at least one preferably cylindrical rotary member, which rotary member is pivotally mounted in a cylindrical recess of the second impeller or the guide body. 40

To be able to compensate for pressure differences between the recesses and the work spaces, it is advantageous if at least one flow connection is formed between the second displacement bodies and the recesses, which at least in a position of the second displacement body penetration of the pressure medium in the recess 45 and / or allowed outflow of the pressure medium from the recess. The flow connection is preferably formed by at least one overflow channel in the first and / or second thickening and / or in the rotary member. It is particularly advantageous if the overflow is separated by at least one control edge in at least two areas, wherein the control edge in at least one position of the second displacement body-50 pers prevents the incoming or outflow of the pressure medium into or out of the recess. In this way, the flow connection is made possible only in predetermined positions of the displacement body.

To vary with the least possible effort speed and / or torque of the driven barrel rades, it is particularly advantageous if the absorption capacity of the first AT 502 908 B1 and / or second impeller preferably independently variable by at least one first and / or second adjusting member are. The sip ratio can be further modified by the volume ratio of the pressure and suction side of the transmission and / or the pressure angle of the second impeller via at least a third adjusting member is variable. 5 This allows the transmission to be replaceable with high efficiency over a wide operating range. In particular, the pressure angle of the second impeller is changed. The working range of a vane machine is due to the Verdrängergeometrie approximately 180 °. This is rotated with respect to the top and bottom dead center of the wing stroke to the pressure angle, which can be changed by the third adjustment. 10

In a particularly preferred embodiment of the invention it is provided that the distance of the axis of rotation of the first and second impeller relative to each other by the first adjusting member is substantially adjustable in a normal to the axis of rotation of the second impeller first adjustment. The second impeller may be mounted in a pivotally connected to the housing 15 supporting body. It is advantageous if the guide body and the support body are adjustable, preferably pivotable, essentially in the first adjustment direction by the first adjustment member. Alternatively or additionally, it may be provided that the guide body is adjustable, preferably pivotable, essentially in the first adjustment direction by the second adjustment member. This makes it possible to adjust the rotational speed 20 and the direction of rotation of the second impeller by the first adjusting member and to vary the torque on the second impeller by adjusting the second adjusting member. This is achieved above all by the fact that the axis of rotation of the first impeller in a central position coaxial with the second impeller is alignable, said middle position corresponds to a speed equal to zero on the second impeller and the axis of rotation of the first impeller in at least two with respect to the center position diametrically opposite operating positions can be brought, wherein the operating positions are assigned different directions of rotation of the second impeller.

The guide body can be formed as a ring and mounted on roller bearings in a rotationally fixed frame or housing, wherein the adjustment frame can be pivotally mounted in the housing.

In order to change the volume ratio between the pressure and suction sides of the entire system, it can further be provided that the guide body is adjustably mounted by the third adjusting member 35 substantially in a second adjustment direction normal to the axis of the second impeller and to the first adjustment direction.

In a very simple embodiment, it is provided that the actuation of the first adjusting member and / or the second adjusting member and / or the third adjusting member via each one eccentric takes place. The eccentrics themselves can be actuated in a mechanical, hydraulic, pneumatic or electromagnetic manner.

In principle, the first, as well as the second impeller can be used as a drive or as a driven wheel. With regard to a simple control of the torque 45 and the rotational speed of the output rotor, it is advantageous, however, if the first impeller is connected to a drive train and the second impeller is connected to a drive train.

The first displacement body formed for example by blades are applied to the running surfaces, wherein the contact points form sealing lines. The connecting channels thus form on the inside of the second impeller each have a sealing edge. Thus, an exact sealing of the displacement chambers in the region of the transition from the pressure to the suction side can be achieved. It is also advantageous if the distance of the sealing lines of two adjacent first displacement body in at least one operating position, that is, depending on the position of the first impeller, - measured along the tread - is smaller than the smallest distance of the sealing edges of two adjacent in the circumferential direction of the connecting channels 5 AT 502 908 B1 of the second impeller. Furthermore, it is advantageous if the displacement space of each impeller faces independently of the angle of rotation a siping space of approximately the same geometry. This avoids a pulsating pressure curve. In order to be able to compensate for leakage losses, the invention further provides for the first impeller to have at least one radial first control channel, which is preferably arranged between two adjacent first displacement bodies, and which corresponds to at least one axial first control channel within the impeller shaft of the first impeller , Furthermore, it can be provided that the first impeller has at least one radia-io len second control channel, which is preferably arranged between two adjacent first displacement bodies, and which corresponds to at least one axial second control channel within the impeller shaft of the first impeller. The control channels are formed by a substantially cylindrical, axially inserted into a cavity of the impeller shaft control shaft. By rotating or shifting the control shaft 15, radial and axial first and second control channels can be fluidly connected to each other. The radial first and second control channels are preferably spaced apart in the direction of the axis of the control shaft. This allows easy loading by the axial control channels. Turning the control shaft changes the absorption capacity and pressure angle of the first impeller. 20

At least one axial control channel can be connected to a container for the pressure medium via a check valve which opens in the direction of the first working chamber. Furthermore, the axial control channels can be used for pressure monitoring of the work spaces. In order to avoid the removal of unwanted vibrations, it is advantageous if the first impeller and / or the inner running surface of the surrounding second impeller are conical. Due to the slightly tapered shape of the first and / or second impeller, a defined lateral position is achieved as a result of the axial component of the force resulting from the pressures and prevents reciprocation of the wheels. 30

An effective lateral seal with minimal manufacturing effort can be achieved if the second impeller frontally, preferably connected by screws, each with sealing end elements. The invention will be explained in more detail below with reference to the figures.

2 shows the transmission in a longitudinal section along the line II-II in FIG. 3 or 6, FIG. 3 shows the transmission in a cross section according to the line III-III in FIG 4 shows a 40 displacement body from FIG. 3 in an oblique view, FIG. 5 shows the displacement body in a front view, FIG. 6 shows the transmission in a cross section analogous to FIG. 3 in a second embodiment, FIG 8 shows the displacement body in a front view, FIG. 9 shows a second adjustment member in a section analogous to FIG. 3 or 6, FIG. 10 shows the detail X from FIG. 9 in a first adjustment position FIG. 11 shows the detail X from FIG. 5 in a second adjusting position of the third adjusting element, FIG. 12 shows an adjusting element of the third adjusting element in a side view, FIG. 13 this adjusting element in a plan view, Fig. 14 shows an impeller shaft of the first impeller with inserted control shaft and Fig. 15 schematically shows the transmission when adjusted by the third adjusting member. 50

The hydraulic transmission 1 has a housing 2, in which a first impeller 3 and a second impeller 4 are arranged. Both wheels 3, 4 are designed as displacement machines forming roller cell runners. The first impeller 3 has radial first recesses 5, in which the first displacement bodies 6 designed as wings are arranged so as to be radially displaceable 55. Analogously, the second impeller 4, second radial recesses 7, 6 AT 502 908 B1 in which second displacement body 8 are arranged displaceably.

Between the first impeller 3 and an inner circumferential surface of the second impeller 4, a first working space 10 functioning as a displacement and swallowing space is formed. The first 5 adjusting members 6 run along the first running surface 9 formed by a cylindrical or slightly conical inner circumferential surface of the second running wheel 4.

The second impeller 4 is connected by screws with end elements 51, 52, which seal the working spaces 10,13 frontally. The end elements 51, 52 have substantially planar end faces 51a, 52a. About the termination elements 51, 52, the second impeller 4 is rotatably mounted in a support body 50.

Between the second impeller 4 and a rotatably mounted on a roller bearing 12 guide body 11 acting as a swallowing and displacement space second working space 13 15 is formed. 11a is a rotationally fixed support ring.

For the flow connection between the first working chamber 10 and the second working chamber 13, the second impeller 4 evenly distributed around the circumference radial connecting channels 15, wherein in each case between two adjacent second radial recesses 7, an Ver-20 binding channel 15 is arranged. The distance between the sealing edges 6a of two adjacent first adjusting members 6 is smaller than the distance between two connecting channels 15. About the pin slot connection 60, the second impeller 4 is rotatably connected to the guide body 11. At the rim 4a of the second impeller 4 while pins 61 are arranged, wel-25 che engage in slots 62 of the guide body 11 and rotate it.

The second displacement body 8 are pivotally arranged in second recesses 7 of the second impeller 4 and in third recesses 44 of the guide body 11. FIGS. 3 to 5 and 5 to 8 show two different configurations of displacement bodies 8. 30

In the embodiment variant shown in FIGS. 3 to 5, the displacement body 8 has a substantially club-like cross section with thickened portions 8a, 8b with a cylindrical surface at both ends. The first thickening 8a is arranged pivotably but immovably in the third recess 44 of the guide body 11. The second displacement body 8 are laterally inserted into the groove-shaped third recess 44 and are thus positively connected to the guide body 11.

The second thickenings 8b of the displacement body 8 are arranged in second radial recesses 7 of the second impeller 4, wherein the second displacement body 8 in the 40 second recesses 7 both radially displaceable, as are pivotable. For pressure equalization, the second recesses 7 can be fluidly connected to the second working space 13. For this purpose, the second thickening 8b formed overflow channels 8c, so that the pressure medium in certain positions of the displacement body 8 can flow into or out of the second recesses 7. However, a pressure compensation 45 is desired and provided only at extreme inclinations of the displacement body 8. In order to prevent in the approximately central working position of the displacement body 8, the flow connection to the bottom of each second recess 7, the overflow channels 8c are interrupted by sealing edges 8d. Thus, in the embodiment variant illustrated in FIGS. 6 to 8, each displacement body 8 is mounted in each case in a substantially cylindrical rotary element 8e. Each rotary element 8e has a substantially cylindrical shape and is rotatably and captively disposed in a cylindrical portion of the second recess 7. The rotary elements 8e are laterally inserted into the groove-shaped second recesses 7. Again, overflow channels 8c are provided for pressure equalization. 7 AT 502 908 B1

As can be seen in particular from FIG. 2, the first impeller 5 and the running surface 9 of the second impeller 4 are conical. This results in a defined position of the wheels 3, 4 due to the resulting axial force components. In this way, unwanted vibration events can be avoided. 5

In the present case, sitting on a rotor shaft 19 first impeller 3 via the impeller shaft 19 with a drive train, not shown, and the second impeller 4 via a traction mechanism 20 and an output shaft 39 is connected to a power take not shown. 10

The impeller shaft 19 of the first impeller 3 is rotatably supported in the housing 2 via rolling bearings 21. To control the speed, direction of rotation and the torque of the output train following adjustment mechanisms are provided: 15 A first adjusting 30 is formed in that the first impeller 3 in a first radial direction Ri normal to the axis of rotation 4a of the second impeller 4 is variable.

The adjustment is effected by a first eccentric 22, which is arranged in a slot 23 of the guide body 11 receiving adjusting frame 24. By rotating 20 of the first eccentric 22 by means of the first actuating member 25, the position of the axes of rotation 3a, 4a of the first impeller 3 and the second impeller 4 is changed relative to each other. The adjustment takes place substantially in a normal plane to the axes of rotation 3a, 4a in a first adjustment direction Ri by pivoting of the second impeller 4 rotatably receiving support body 50 which is pivotally connected to the housing 2. This causes a 25 change in the rotational speed of the second impeller 4. If the first impeller 3 is positioned concentrically to the second impeller 4, the second impeller 4 comes to a standstill, since no pressure difference between adjacent cells longer arises. When changing the axis of rotation 3a of the first impeller 3 with zero crossing and the direction of rotation of the second impeller 4 can be changed. 30

A second adjusting member 31 is formed in that the guide body 11 can be changed in relation to the second impeller 4 in the first adjustment direction Ri normal to the axis of rotation 4a of the impeller 4. The guide body 11 is pivotally mounted in the housing 2 via a third eccentric 41 or an axis. The adjustment of the adjusting frame 24 relative to the second impeller 4 35 via a rotatable in the bore 28 of the adjusting frame 24 second eccentric 26 by pivoting the guide body 11. This adjustment is much lower and finer than the adjustment by the first adjusting member 30, wherein a zero crossing is not allowed. In this way, the torque of the second impeller 4 can be changed. 40

Furthermore, a third adjusting member 40 is provided, with which the volume ratio between the pressure and suction side of the entire system can be changed. The adjustment takes place via the third eccentric 41, which acts diametrically on the first eccentric 22 in a second adjustment direction R2 on the adjustment frame 24, as shown in FIGS. 9 to 13. If the third eccentric 41 in the bore 43 of the adjusting frame 24 is rotated via the actuating member 42, then the location of the smallest approach W1 is displaced, as shown in FIGS. 10 and 11. Thus, the pressure angle ß is changed. The contact angle β is the angle by which the work area of a vane machine which is approximately 180 ° wide is rotated in relation to the top and bottom dead center of the vane stroke. 50

The acting as a pump first impeller 3 and acting as a machine second impeller 4 form a substantially closed hydraulic circuit. However, leakage losses are hard to avoid. In order to compensate for the leakage oil losses, special measures are required, which are shown in Fig. 14. The first impeller 3 has evenly distributed around the circumference radial first and second control channels 33, 34, which two axial 8 AT 502 908 B1 first and second control channels 33a, 34a are fluidly connected within the impeller shaft 19 upon rotation of the impeller 3. The axial control channels 33a, 34a are arranged in a separate stationary control shaft 35 which is inserted into a cavity 36 of the impeller shaft 19. As the first impeller 3 rotates, the radial first and second control passages 33, 34 spaced in the direction of the 5 axis of the control shaft 35 sweep the apertures 33b, 34b of the axial control passages 33a, 34a. By turning the control shaft 35 thus the rotation angle can be adjusted, in which the radial with the axial control channels 33, 34; 33a, 34a are connected. This allows both the pressure in the working space, as well as the contact pressure of the blades are controlled on the treads. This io makes it possible to influence the working range of the first impeller 3 by changing the pressure angle α. The maximum contact angle α results from the displacement geometry of the system and is 360 / (2 * z), where z is the number of displacement bodies. If a displacement body enters the pressure range, pressure can only be built up from this angle. In order to avoid a drop in efficiency, the underside of the Ver-15 is urängungskörper the first impeller 3 up to the opposite side on the bottom dead center of the Flügelhubes beyond the radial second control channels 34 and the first recesses 5 pressurized. While in conventional pumps, the pressure angle is fixed and can not be changed, it is variable in the present transmission. 20

The apparent from Fig. 6 pressure angle ß of the inner system surrounding the outer system is essentially determined by the inner system and the radial connection channels 15. It must be ensured that the pressure of the inner system does not fill a working space of the outer system whose volume is reduced by the rotational movement of the second impeller 4. This is done by turning the upper and lower dead center of the outer system in relation to the inner system. If the first impeller 3 changes its direction of conveyance by pivoting the axis 3a, the pressure angle β of the outer system also shifts by approximately 180 ° and, in order to obtain a good efficiency, can be adapted to these new flow conditions. Even in the case that changes the direction of rotation of the first impeller 3, the pressurization of the wing underside via the first recess 5 and the radial second control channels 34 and thus the contact angle α of the first impeller 3 can be adjusted by about 180 °. Again, the outer system must be tuned to the inner system. The same fine tunings can also be performed when the second impeller 4 is to operate as a pump and the first impeller 3 as a motor, for example, when braking a vehicle via a transmission-motor unit when going downhill.

The control shaft 35 thus forms a fourth adjusting member 70 to control speed and torque of the hydraulic transmission. The control shaft 35 also allows 40 other functions.

If there is not enough pressure medium on the suction side to fill all the cells, then the missing pressure medium via one of the two axial control channels 33a, 34a from a container, not shown, for the pressure medium, 45 for example from a radial control channels 33, 34 Oil tank within the housing 2, sucked. The respective other control channel 34a, 33a communicates with the pressure side, wherein a non-illustrated check valve prevents the flow of the pressure medium into the container. If the pressure and suction sides are reversed, the control channel 33a is automatically blocked by the associated non-return valve and the missing oil can be sucked in via the control channel 34a. Basically, the control shaft 35 is such that it prevents overflow of the pressure medium from the pressure to the suction side of the first impeller 3. The control shaft 35 can also assume a safety function. If the pressure in the system becomes too high for some reason, rotation of the control shaft 35, e.g. by 90 °, an overflow of the pressure medium through the openings 33b, 34b are made possible. As a result, the control shaft 35 can also assume the function of an overpressure safety device. In this case are

Claims (28)

9 AT 502 908 B1 flexible cables are an advantage. Furthermore, it is possible to carry out pressure monitoring of the pressure and / or suction side of the system by means of pressure sensors connected to the axial control channels. FIG. 15 schematically shows the transmission 1 during an adjustment process by the third adjusting member 40. The displacement or swallowing spaces V1, V2 of the first working chamber 10 remain the same. The displacement or displacement spaces V3, V4 of the second working space 13 change approximately by the volume of V5. Since the spaces 10, 13 are in operative connection through the connecting channels 15 in the second impeller 4, the volume ratio between the pressure and suction side of the entire system can be changed by turning the third io eccentric 41. By contrast, nothing changes in the inner system. By the described hydraulic transmission 1, a harmonious transition between the drive train and the output shaft can be achieved and within the design range every 15 changes in speed are made possible. 1. Hydraulic transmission (1) with harmonic transition of the pressure medium between two trained as a cell rotor displacement machines, with a radially displaceable first displacement body (6) having first impeller (3) and a radially displaceable second displacement body (8) having the second impeller (4 ), wherein the first impeller (3) within the second impeller (4) is arranged and the first Verprängungskörper (6) of the first impeller (3) along a cylindrical running surface (9) of the surrounding second impeller (4) are guided and between the two wheels (3, 4) at least a first working space (10) and a second working space (13) between the second impeller (4) and a surrounding guide body (11) is formed, wherein the second impeller (4) at least a radial connection channel (15) for 30 flow connection of the first and the second working spaces (10, 13), characterized gekennzeic hnet that the second impeller (4) and the guide body (11), as known per se, are rotatably connected to each other and that the second displacement body (8) on the outside of the second impeller (4) and / or on the inside of the guide body ( 11) are radially displaceable and / or pivotally guided. 35 2. Transmission (1) according to claim 1, characterized in that the rotary connection between the second impeller and the guide body, as known per se, via at least one pin slot connection (60) between the second impeller (4) and the guide body (11). takes place, preferably at the rim (4a) of the second impeller (4) 40 a plurality of pins (61) are arranged, which engage in corresponding slots (62) of the Füh approximately body (11). 3. Transmission (1) according to claim 1 or 2, characterized in that each second displacement body (8), as is known, at one end both radially displaceable, and pivotally 45 in a radial recess (7) of the second impeller ( 4) or the guide body (11) and at the other end immovably, but pivotally in a radial recess (44, 7) of the guide body (11) and the second impeller (4) is arranged. 4. Gear (1) according to one of claims 1 to 3, characterized in that the second displacement body (8), as known per se, at one end a cylindrical first thickening (8a), via which the second displacement body (8 ) is pivotally mounted in a preferably cylindrical recess (44, 7) of the guide body (11) or the second impeller (4). 55 1 0 AT 502 908 B1 5. Transmission (1) according to one of claims 1 to 4, characterized in that the second displacement body (8) has at least one second end a preferably cylindrical second thickening (8b), via which the second displacement body (8) in a recess (7, 44) of the second impeller (4) and the guide body (11) both ra- 5 dial displaced, and is stored. 6. gearbox (1) according to one of claims 1 to 5, characterized in that the second displacement body (8), as known per se, at least one end radially displaceable in at least one preferably cylindrical rotary member (8e) is mounted, which io Rotary element (8e) in a cylindrical recess (7, 44) of the second impeller (4) and the guide body (11) is pivotally mounted. 7. Transmission (1) according to one of claims 3 to 6, characterized in that between the second displacement body (8) and the recess (7) in each case at least one flow connection (16) is formed, which at least in one position of the second displacement body (8) allows penetration of the pressure medium into the recess (7) and / or outflow of the pressure medium from the recess (7). 8. transmission (1) according to claim 7, characterized in that the flow connection 20 (16) by at least one overflow channel (8c) in the first and / or second verdi ckung (8a, 8b) and / or in the rotary member (8e) is. 9. gearbox (1) according to claim 8, characterized in that the overflow channel (8c) is separated by at least one control edge (8d) in at least two areas, said 25 control edge (8d) in at least one position of the second displacement body (8) the inflow or outflow of the pressure medium in or out of the overflow (8c) prevents. 10. gear (1) according to one of claims 1 to 9, characterized in that the 30 swallowing capacity of the first and / or second impeller (3, 4), preferably independently, by at least one first and / or second adjusting member (30, 31) are changeable. 11. Transmission (1) according to one of claims 1 to 9, characterized in that the volume ratio of the pressure and suction side of the transmission (1) and / or the pressure angle (ß) of the second impeller (4) via at least one third adjusting member (40) is variable. 12. Transmission (1) according to claims 10 or 11, characterized in that the distance of the rotation axis (3a, 4a) of the first and second impeller (3, 4) relative to each other by the first adjusting member (30) substantially in one of Rotary axis (4a) of the second impeller (4) normal first adjustment (R ^ is adjustable. 13. Transmission (1) according to any one of claims 12, characterized in that the axes of rotation (3a, 4a) of the wheels (3, 4) in a central position coaxially aligned with each other, 45 at this middle position of a speed equal to zero at the aborted Impeller (4) corresponds. 14. Transmission (1) according to claim 13, characterized in that the axis of rotation (3a, 4a) of the first impeller (3) and / or the second impeller (3, 4) can be brought into at least two with respect to the central position diametrically opposite operating positions, wherein the so operating positions different directions of rotation of the aborted impeller (4) are arranged to. 15. Transmission (1) according to any one of claims 10 to 14, characterized in that the rotational speed and the direction of rotation of the abraded impeller (4) by the first adjusting member 55 (30) is adjustable. 1 1 AT 502 908 B1 16. Transmission (1) according to one of claims 1 to 15, characterized in that the second impeller (4) in a pivotally connected to the housing (2) supporting body (50) is mounted. 17. Transmission (1) according to one of claims 10 to 16, characterized in that the guide body (11) and the support body (50) by the first adjusting member (30) substantially in the first adjustment direction (Ri) is adjustable, preferably pivotable , 18. Transmission (1) according to any one of claims 10 to 17, characterized in that the io guide body (11) by the second adjusting member (31) substantially in the first adjustment direction (R ^ adjustable, preferably is pivotable. 19. Transmission (1) according to one of claims 10 to 18, characterized in that the torque on the driven impeller (4) by adjusting the second adjusting member 15 (31) is variable. 20. Transmission (1) according to one of claims 10 to 19, characterized in that the guide body (11) by the third adjusting member (40) substantially in one to the axis (4a) of the second impeller (4) and the first adjustment ( Ri) normal second Ver 20 adjustment direction (R2) is adjustably mounted. 21. Transmission (1) according to any one of claims 10 to 20, characterized in that the actuation of the first adjusting member (30) and / or the second adjusting member (31) and / or third adjusting member (40) via in each case an eccentric (22, 26, 41) takes place. 25 22. Transmission (1) according to one of claims 10 to 21, characterized in that the guide body (11) in an adjustment frame (24), preferably roller bearings, is rotatably arranged, wherein the adjustment frame (24) particularly preferably via the eccentric (41 ) of the third adjusting member (40) is pivotally mounted in the housing (2). 30 23 transmission (1) according to one of claims 1 to 22, characterized in that the first impeller (3) has at least one radial first control channel (33), which is preferably arranged between two adjacent first displacement body (6) which at least an axial first control channel (33a) within the impeller shaft (19) of the first impeller (3) corresponds. 24. Transmission (1) according to one of claims 1 to 23, characterized in that the first impeller (3) has at least one radial second control channel (34) which is arranged in the region of a first displacement body (6) and preferably in the region of 40 first recesses (5) for the first displacement body (6) opens, wherein the second control channel (34) with at least one axial second control channel (34a) within the impeller shaft (19) of the first impeller (3) corresponds. 25. Transmission (1) according to claim 23 or 24, characterized in that at least one 45 axial control channel (33a, 34a) is formed by a substantially cylindrical, axially into a cavity of the impeller shaft (19) inserted control shaft (35) by rotation and / or displacement of the control shaft (35) radial and axial control channels (33, 33a, 34, 34a) of the same name are fluidly connected to one another. 26 gear (1) according to one of claims 23 to 25, characterized in that the control shaft (35) forms a fourth adjusting member (70), wherein the pressure angle (a) of the first impeller (3) by twisting and / or shifting of the control shaft (35) is variable. 27 transmission (1) according to one of claims 23 to 26, characterized in that at least one axial control channel (33a, 34a) is preferably connected via a check valve with a container for the pressure medium. 28 transmission (1) according to any one of claims 23 to 27, characterized in that at least 5 an axial control channel (33a, 34a) is in communication with a pressure sensor. 29. Transmission (1) according to one of claims 1 to 27, characterized in that the first impeller (3) and / or the inner running surface (9) of the surrounding second impeller (4) are conical. 10 30. Transmission (1) according to one of claims 1 to 27, characterized in that the second impeller (4) at the end, preferably via screws (53), in each case with sealing end elements (51, 52) is connected. 15 For this purpose 6 sheets Drawings 20 25 30 35 40 45 50 55