DE974232C - Hydraulic displacement device, pump or motor, especially for gearboxes - Google Patents

Description

Hydraulic displacement device, pump or motor, in particular for transmission The invention relates to a hydraulic displacement device, pump or motor, especially for gearboxes, with a reversing device through which the displacement chambers switched from the suction to the pressure side and vice versa and with a device by means of which the pressure in the displacement chambers, while these are closed off from the suction and pressure side, in addition to its size to the changes in the displacement spaces due to the design of the facility pressure changes caused is influenced.

It is known that with hydrostatic transmissions, especially when these devices operate at high operating pressures and also at high speeds run around, annoying noises and unwanted vibrations occur that one has sought to attenuate or reduce it by arranging throttle slots. By choosing a different size overlap and relocating it from the Dead center position, it is possible to reduce noise and reduce vibrations to reach.

It has also been proposed in a press oil transmission, which Cylinder spaces closed during the transition from the pressure side to the suction side are to carry out a pilot control by means of an additional movement given to the piston, either with eccentric piston gears through one of the central axis of the reversing bars offset arrangement of the crank pin or, in the case of drive flange gears, by a Inclination of the swivel axis of the swivel frame from the gear axis out towards the print side.

In all of these embodiments, however, at high operating pressures and high speeds do not eliminate the noises and vibrations that occur will.

So one has z. B. in a capsule pump engine, the two in one Housing eccentrically arranged, provided with vane pistons, as a pump element or has runners acting as the drive element of the oil motor and their displacement spaces by a common hollow shaft, which in the axial direction into a suction channel and a pressure channel is subdivided, and by radial bores provided in the rotors are in communication with each other and in which between the radial bores each a runner facing openings of the pressure channel and the suction channel special Reversing webs are left standing when the runner passes through its dead center position close the displacement chambers and thus a connection of the suction side with the Prevent pressure side to eliminate the difficulty in the displacement spaces a different pressure prevails than in the pressure channel or in the suction channel, as a result of which a pressure equalization causing annoying noises takes place as soon as the displacement spaces can be connected again to one of the two channels, which is determined by the dimensions and arrangement the reversing bars caused reversal times of the displacement spaces so compared to the The dead center position of the runners shifted so that the volumes of the during the Reversing closed displacement spaces due to the eccentric arrangement of the Runners change in their housings and thereby an alignment of the ones prevailing in them Pressures is brought about by the pressures prevailing in the pressure channel or the suction channel.

This type of influencing the prevailing in the displacement spaces Pressures due to a shift in the reversing times is, however, due to the special Dimensions and arrangement of the reversing bars only for very specific ones, in which Pressure channel or pressure conditions prevailing in the suction channel are suitable. Should However, if these pressure conditions experience a change, the reversing bars must can be exchanged for those with different dimensions that change the Changeover time and thus a corresponding adjustment in the displacement spaces allow the prevailing pressures to the new pressure conditions.

Attempts have also been made to reduce the pressure in the individual cylinders or Displacement spaces, while this is from the suction side as well as from the pressure side are locked, to be influenced by the fact that they are through holes with a piston valve type Brings valves in connection, the pressure in the displacement chambers during the Should influence reversing times accordingly.

The time periods available for this, which are Fractions of a second act, however, are so short that these means, viz Piston slide type valves or rotating rotary slide valves, due to the effects of the mass these agents, are unable to provide adequate noise attenuation or attenuation of causing vibrations. At very high speeds and at relatively high speeds The force impulses that reach the control slide are sufficient for high working pressures is no longer sufficient to effect a proper steering movement of the control element.

The invention solves the known problem of eliminating Noises and vibrations even at high speeds and high performance an additional influencing of the pressure curve free of mass effects Withdrawal or introduction of oil flows from the cylinders or into the same with the aid low-mass valves or special oil pumping stations or oil motors.

This will cause a significant decrease in the controls occurring acceleration forces achieved, which in turn a perfect reversal in the gearbox even at high operating speeds and operating pressures.

By withdrawing or introducing streams of oil from the cylinders or in the same with the help of low-mass valves, which only require a small stroke, can also be used in the short periods of time that only count to thousandths of a second, within which in a high-speed transmission the displacement spaces both can be blocked from the suction as well as from the pressure side, an influence of the pressure in the displacement spaces so that disruptive pressure peaks or disruptive pressure reductions can be avoided.

When arranging one or more pumps that have a similar set up Introduce bores pressure oil into the displacement chambers or lead them out of them, In the event of a discharge, the oil pump acts as an energy recovery unit Oil engine, which is, however, insignificant for the effect, so that here in the following par excellence One speaks of »pumps«, although some of these are oil engines can. With this measure, too, one cannot be delayed by mass effects and by changing the pump delivery variable influencing of the pressure development achieve in the displacer cells, as is essential for the invention.

Another means with which also delayed on the print development in the displacement cells during their transition from the suction to the pressure side, and vice versa, can be acted on, is the arrangement of a rotatable reversing device. This allows the phase position of the piston stroke movement at the times of transition Influence each displacement cell from the suction to the pressure side and vice versa and thus also the development of pressure in these, with every disturbance being caused by mass action is avoided.

The implementation of the invention requires that absolutely during the displacement cells, albeit a small angular amount of the rotation of the gear shaft are shut off from both the suction and the pressure side. Gear types, in which for some reason this angular amount is zero or even negative is, therefore, are for the Application of the invention unsuitable. Such Gear types are z. B. those - not more general, but only in older ones Descriptions of the known - kind, in which you can twist the control pin, for example, in a radial piston gear, trying to influence the delivery rate Has. If the latter is to succeed, the coverage must be almost zero or negative, because here the control pin to enable the required strong reduction the delivery rate rotated out of the dead center of the piston movement by large angular amounts must become. In this case the pistons have high speeds during the reversal, so that any overlap can lead to hard blows or to the destruction of the gear unit would, d. that is, it is then not at all accessible, the displacer cells, even if only a short time to shut off both from the suction side and from the pressure side.

The execution of a twistable reversing device is also From a purely structural point of view, it is almost impossible to implement, especially for an appropriate pressure control Large twists in the displacement cells to be reversed with a small useful stroke the reversal would be necessary, which is hardly related to the task of the pressure oil supply and discharge can connect. According to the invention is therefore for this type of pressure influencing in the displacement cells, the reversing device set up so that they except in the usual direction used to adjust the stroke is also shifted perpendicular to it or can be rotated, whereby the phase position of the piston movement to the reversing device can be changed so that the pressure influencing according to the invention in the reversed Displacement cells can be made unaffected by mass action.

Fig. I shows an embodiment of the invention, namely in the View of the control surface of an axial piston transmission, although the invention in exactly the same way for all types of the usual slide reversal, so too for ripple control, as shown by most radial piston gears, can be used is. I and 2 are the well-known, sausage-shaped control slots of an axial piston gear, where I z. B. the pressure side and 2 means the suction side. By known means like twisting the control, each cylinder can be made which with its control opening, which is assumed to be round in Fig. I and shown in dotted lines 3 is involved in the reversal during the period in which this opening 3 is not connected to either the pressure side i or the suction side 2, a compression or expansion is subjected. Is in Fig. I the direction of rotation indicated by the arrow left, the cylinder opening 3 must be in the upper part of the picture at the transition from 2 on I are subjected to a compression process. So now this about for the maximum load or the maximum air content of the oil coordinated compression process does not go too far at part load or with low-air oil, the control surface is between the pressure and suction slots I and 2 provided an opening 4, which is approximately from the Cylinder opening 3 at an appropriate moment, some time after seeing the suction slot 2 has left, is touched upon. The opening 4 is now, as can be seen in Fig. 2 is, which is about a section A-B through Fig. I, with one with smaller Mass executed check or safety valve 5 in connection, which is about consists of a spring-loaded plate and is shown in Fig. 3 on a larger scale is. This valve opens a connection between the cylinder opening 3 and the Pressure slot I as soon as a higher pressure in the cylinder 3 than in the pressure slot I occurs, the preload of the spring still has to be overcome. By execution of the valve with the smallest possible mass - for example as a light plate 6 in Fig. 3 -, Arrangement of a moderately stiff spring 7 in Fig. 3 and a recess 8 in the plate 6, which has a sufficiently extensive spread of the through the opening 4 entering pressure up to the sealing edge zones of the plate 6 allows ensure that this valve works with the required speed, so that no disturbing noises occur even when such a transmission is idling, even if there is sufficient compression for full load and possibly aerated oil having.

Similar to that described for the compression in the upper half of Fig. I, An expansion that goes too far can also be seen in the lower half of Fig. I eliminate when the opening 4 'provided there is connected to a suitable valve that allows oil to flow into the cylinder from the suction side as soon as it is in this too far expansion occurs. For this purpose an arrangement would have to be about one Plate valve similar to Fig. 3, but with the plate closing direction in the opposite direction, to get voted. Instead, you can limit yourself to that, for example in the Place two 4 "openings in the middle of the reversing valve, which can be accessed via non-return valves so with the suction line of the gearbox, for example with the feed pressure line, which is below the pressure of a filling or feed pump, connects that here at least always the feed or filling pressure prevails and thus an expansion that goes too far or a vacuum build-up in the cylinders is prevented, even if it goes too far Expansion movement of the piston should occur. The openings 4 and 4 'in Fig. I for a primary part with alternating suction and pressure side I and 2, in which case only for a corresponding and sufficient compression movement the piston needs to be taken care of. A refill via the openings 4 "from the feed pressure line is obviously compatible with the invention shown in Fig. i without further ado Decompression valve, so that no further additions are necessary if does not also change the direction of rotation.

For a changing direction of rotation, the design according to Fig. Q now results. an appropriate arrangement of the decompression valves. The openings q. are here initially, as can be seen in more detail in Fig. 5, by means of a spring-loaded valve plate 6, similar to Fig. I and 2 explained, locked. However, this valve opens not a path to a specific one Side of the transmission circuit, but to a transverse channel g, which has a simple switching device, for example the ball Io rolling in it, in each case the connection to that side I or 2 of the gearbox that has the higher pressure. This becomes a automatic switching of the decompression valve according to the invention to the side of higher pressure achieved.

The valve arrangements described here in some exemplary embodiments can be selected so that they have a correct setting for all operating states the compression or expansion, provided that the total corresponding movements of the piston are sufficiently large to the operating fluid compress or expand, including the necessary additional movements, which linkage play, greater air content of the oil or flexibility of the components of the relevant transmission part. To, for example, change the direction of rotation to achieve a sufficiently large piston movement during the reversing time is it only needs to be the overlap, d. H. the difference in the width of the sealing reversing web to choose between the pressure and suction slot I and 2 sufficiently large. For a primary part (Oil pump) then always perfect conditions result, if one on the one hand ensures that there is no lower pressure in any cylinder during the reversal than atmospheric pressure or, if there is an increased pressure on suction side 2, the so-called feed pressure prevails, a lower pressure than this feed pressure occurs can, for which a corresponding non-return or filling valve 4 "(Fig. I) in each Reversing bar is sufficient. But besides that, it is still necessary to make sure that too no higher pressure than the high pressure in the gearbox during such a cylinder the reversal can arise, and if one considers this condition independent of the Wants to maintain the direction of rotation or, in other words, seeks an arrangement, which results in the correct proportions for each direction of rotation of a primary part the valve arrangement according to Fig. 5 is given for this.

Similar valves can also be cited for such transmission parts, which are used as an oil motor. Provided that with these the size of the stroke may be adjustable, but never the adjustment of the Stroke goes so far that the stroke direction is reversed, is for such a Oil motor on the side of the reversing which corresponds to the smallest piston strokes, a valve according to Fig. 5 required to limit the maximum pressure, while on the other reversing bar, which corresponds to the largest piston strokes, a refill valve or suction valve is necessary, which ensures that the smallest feed pressure is never here is fallen below. In addition, there are at least at least for each reversing bar alternating direction of rotation two controlled by slots similar to 4 and 4 'in Fig. I. Valves required, namely two filling valves on the side of the smallest stroke, which prevent lower pressures on the side in question than in the neighboring one Pressure or suction slit occur while, conversely, on the side of the largest Stroke two drain valves controlled in the same way are necessary for this ensure that there never are higher pressures than in the neighboring suction or pressure slot may occur.

Numerous other valve arrangements can be devised, which somehow completely or semi-automatically influence the compression or expansion. The details of the valve arrangements are immaterial to the invention. Essential is rather the basic idea for the present embodiment of the invention the addition of the actual slide reversals intended for large amounts of liquid through simple and fast-acting, practically mass-free valve arrangements that more or less automatically or maybe even under the influence of the hand or any other kind of controlled influence, but unaffected by disruptive ones Mass effects, the pressure development in the displacer cells to be reversed, individually for each displacer cell to be redirected in the correct manner.

In the illustrated embodiments of the invention, the additional Valves housed in the reversing area. Of course, similar ones are also possible To accommodate valves in the mostly rotating cylinder body. Usually is However, this is less advantageous, since then for each of the usually numerous cylinders a hydraulic transmission, the corresponding valve arrangements are necessary while in the illustrated embodiment of the invention, the arrangement of the required Valves only at the two reversing points is sufficient.

Influencing the pressure in the displacer cells to be reversed can also be achieved by in the cylinders to be reversed are usually variable with the help of a pumping station introduces the oil flow to be set or, conversely, withdraws it therefrom, with then the pump may work as an oil motor.

In Fig. 6, for example, the corresponding device is now shown Invention shown for an axial piston transmission, mainly in the view of the usually fixed control surface of an axial piston transmission. This has the usually sausage-shaped control slots 2 and i, the each in connection with the suction or pressure line of the hydraulic transmission system standing, but changing roles frequently.

The individual cylinders, for example seven, grind with the In Fig. 6, for the sake of simplicity, circular dotted openings represent the control slots 2 and i and when reversing the fixed reversing webs located between these i2 and 13- In Fig. 7 the same device is again in longitudinal section the center of the mostly rotating cylinder body is shown, with only the body = q. the non-rotating reversing surface is shown in cross section as well as the The cylinder body 15, while the piston 16 and the rest of the engine are connected to the connecting rod 17 hanging on the drive shaft 18, are only shown in. Outlines, especially since the details of these parts are immaterial to the invention. In the reversing area 14th the openings are now appropriately approximately in the middle of the reversing webs 12 and 13 4 attached. In this z. B. from the main oil tank via the pumps Io and 2o an oil flow introduced when a compression process is to be achieved, or returned to the oil reservoir when expansion is to take place. The properties A good pump, which is also tight enough for high pressures, guarantees a not disturbed by the action of the mass and arbitrary when using variable pumping stations adjustable influencing of the pressure development in the displacement cells to be reversed. Instead of the pumps I9 and 2o, only a single pump or the like can also be used find that sucks about operating fluid from one opening 4 and into the other Opening 4 conveyed in (see. Fig. 7).

Fig. 8 now shows a special arrangement of a pumping station, which is suitable in itself, the disruptive movements of the gear piston 16 during to compensate the changeover time and at the same time the desired oil quantities for the Influencing the compression or expansion or to achieve these processes to be introduced into the openings 4. The pump I9, 2o consists of a pump piston, which hangs on a crank mechanism 23. This crank drive is for example with a 7-cylinder gearbox through a spur gear ratio in the ratio 7: 1 driven by the drive shaft I8. If one then selects the relative position of the crank 23 so that when the cylinder 15 to be reversed with its cylinder opening, for example I5a, has reached its dead center, which is the case with untwisted control, if it is in the middle of the associated reversing web 12 or 13, so a complete compensation of the disruptive movement of the gear piston is achieved 16 if the total stroke volume of the pump piston I9 or 2o is a forty-ninth of the currently selected or present stroke volume of the gear cylinder 15 is. It is thus possible to reverse the direction using a single auxiliary pump I9 to accomplish on a reversing web for all cylinders and this still run relatively small. You need one for the other reversing bridge Similar pump 2o, or the auxiliary pump according to Fig. 8 would have to be double-acting to introduce oil on the one reversing bar for this compression to be able to take oil from the other for the expansion. Completely unrestricted However, this only applies to gearboxes with an even number of cylinders, which are generally made other reasons are not common, so that two pumps I9 and 2o are usually necessary when accurate compensation for the natural movement of the gear piston 16 should be reached. Finally, it is also possible to use a pump, which alternately supplies one and the other opening 4, including some switching device would be applicable.

The same pumps I9 and 2o can also be used usefully for the required compression or expansion, for which one only needs to unscrew the crank 23 from the previously specified angular position with respect to the drive shaft of the transmission part at the dead center position of a piston. In Fig. 8 this is achieved, for example, in that the spur gears which connect the drive shaft 18 to the crank 23 are helically toothed, so that a longitudinal movement, for example of the pinion on the crankshaft 23 by means of the linkage 25, the desired setting of the phase position of the crank 23 permitted. In addition, of course, an adjustment of the stroke size of the crank 23 is also necessary if the main transmission part has variable piston strokes or the operating pressure changes significantly. The setting of this crank can be done with known means, for example by using a drive with longitudinally displaceable inclined cams instead of the simple crank mechanism with a fixed cylinder and rotating crankshaft, or the known arrangement of the radial or axial piston engines of the hydraulic gears with rotating cylinders and fixed crank. In this case, of course, the single rotating cylinder does not have to be equipped with a reversing device 14 as shown in FIGS.

That of course the pump cylinders 19 and 20 with liquid must be filled, appropriately also with pre-stressed liquid, is here just mentioned. In Fig. 8 only the check valve 26 is on a small one for this purpose Oil reservoir indicated, although usually a connection to a pressurized one upright feed pressure line via a similar check valve will be. The details of the reversing device and in particular the pumps I9, 2o can still be changed in very different ways without this the basic idea of the invention suffers adversity. It is essential for the design of the present invention, the arrangement of inflow and outflow openings in the reversing member the hydraulic gears and the connection between these inlet and outlet openings, those with fast-acting, almost mass-free valves or with the Oil flows from special pumping stations that are not subject to the effects of mass in connection to be brought.

Instead of feeding and discharging the liquid through openings 4 on the reversing element, as shown in FIG. 6, these oil flows can of course also be introduced elsewhere. In Fig. 7, for example, a sliding ring 22 is provided which passes over individual openings of the cylinder and allows the individual bores to achieve approximately the same effects as the openings 4 in the reversing web 14. Outlet openings in particular can be arranged in the form of small valves operated by a cam ring 22, with the further advantage that such valves can remove the foreign bodies ejected by centrifugal force from the compression chamber of the transmission. Of course, other types of connection between the pumps zg, 20 and the individual cylinders 15 can also be implemented without changing the essence of the invention. It is also possible to use the pumps zg, 2o in the form of individual plungers in the control bodies 14 of Fig. 7, since these are only structural measures that mainly achieve the same thing as the embodiment shown schematically in Fig. B.

Another embodiment of the invention, which the influencing of the pressure in the cylinders to be reversed, unaffected by the action of the mass, results, as already mentioned at the beginning, by twisting the reversing device, this measure of course also with the measures already described the arrangement of floating, fast-acting valves can be combined.

The implementation of a reversing surface that can also be twisted during operation with axial piston gears or a twistable pin with radial piston gears or a twistable housing in a capsule pump type gearbox but is usually quite difficult to build, especially because of small useful piston strokes quite large amounts of twist are necessary. Twisting becomes particularly uncomfortable and reversal when the useful piston strokes are very small or almost zero should, because then obviously a twisting of the control of almost 9o degrees of angle what is required is a simple design of the oil supply and drainage hardly tolerated. If the direction of rotation or pressure changes, the twisting must as a rule be made in the opposite sense, which increases the difficulty of making the Fluid supply and discharge to the control surface increases even further.

In particular in the case of a compression or expansion process a special embodiment of the invention is found in the case of small usable piston strokes as very advantageous, instead of the twistable control surface with or without additional compensating valves results in a particularly simple arrangement that up to to a certain extent it even comes to the same thing as a very far-reaching one and twisting of the reversal that automatically adapts to the stroke size. this will according to the invention achieved in that one in transmissions in which the adjustment the stroke sizes of the working pistons through a longitudinal movement in a certain direction takes place, the control is adjusted additionally and perpendicular to this direction. This is the case, for example, in radial piston gears of the usual design, in which there is usually a cylindrical reversing pin and a drum or circular path guide for the pistons, which can be adjusted relative to one another in a certain direction, that the useful strokes of the pistons change. The sledge that this mostly in a straight line Direction of progressive adjustment - in some versions this adjustment takes place even on an arc of a relatively large diameter - accomplished, is now set up according to the invention so that it is also perpendicular to this direction of adjustment can be pushed out of the symmetrical central position. This results in a movement of the pistons whose phase is 90 degrees to the actual useful movement is shifted and that too, as long as the transverse shift remains unchanged remains unchanged. The resulting situation of the change of direction decreases then an angular position which, depending on the size of the stroke, is close to the actual one The working stroke adjustment direction is or, in the case of small strokes, perpendicular to it.

In the case of the axial piston transmission, kinematically the same can be done as here with reference on the radial piston gear described, can be achieved when one of the pivoting the cylinder or the drive ring makes about an axis that is opposite to the usual Pivot direction is inclined, approximately at a right angle. With the axial piston gear this leads in particular to the measure which can also be carried out structurally very easily the pivoting about an auxiliary pivot axis perpendicular to the main pivot axis, to which Purpose of a cardanic or spherically movable mounting of the movable gear part, So the movable drive ring or the pivotable cylinder body, appropriately is when one is not with a fixed, unchangeable lead or lag can be satisfied with what z. B. at constant operating pressure is often sufficient, as this is under these operating conditions the correct reversal for all stroke sizes including Zero stroke and reverse running or transition from pump operation to oil motor operation, and vice versa, can be achieved. You can often use the swiveling one in the simplest way Keep part of the gearbox in a spherical surface, which makes it possible to create all the desired Adjustments of the reversal, including one that may also be desired To accomplish twisting the reversal.

The invention is applicable to both axial piston drives with pivotable Cylinders and a fixed drive shaft or tiltable, rotating around the fixed drive shaft Drive ring applicable.

Fig. G shows an embodiment of the invention for the known Axial piston gear with swiveling cylinders. 28 is the drive shaft which is in front the drive flange 29 carries in a known manner. These are with the usual ball joints the piston rods and pistons 16 are attached to the rotating cylinder block 15 work. Instead of using the rotating cylinder block 15 in the usual way the associated, non-rotating control surface 3o in a around a certain axis to store pivotable frame, a ball-movable in a manner according to the invention Frame 31 applied. This frame can move spherically with both his Outside on any connected with the housing or the drive shaft bearing Parts can be hung, or it can, as shown for example in Fig. G, in the manner of a hemispherical shell, which only has a matching, mostly slit-shaped opening for the shaft 28 leaves free, the drive flange 2g and a drive flange bearing enclose comprehensive hemisphere 32.

In this way it is evidently possible to bend the control surface 39 about any pivot axis, since the hemisphere 32 allows mobility in all directions. In addition, however, it is also possible to twist the control surface 3o about the longitudinal axis of the cylinder 15, because this mobility is apparently also made possible by the hemispherical bearing 32, in contrast to the simple pivot pin bearing. The described spherical mounting of the drive shaft in the frame 3I initially allows the main mobility of the transmission, in particular the twisting of the control and its bending about an axis twisted to the usual pivot axis. In contrast, it is initially less important how the mechanical structure, consisting of the swivel frame 3I with the drive shaft 28 guided in a ball, is otherwise suspended or held. For example, one can think of giving the frame 3I about two pivot pins 33 which, if necessary, serve simultaneously for the oil supply and drainage. In this case, the required pivot angle setting using the hemispherical bearing 3I can only be effective if the drive shaft 28 is set up so that its left end is movable accordingly; pivoting about an axis perpendicular to the pivot pin means 33 can, for. B. can be achieved by providing the shaft 28 on the left with a movable coupling and making the frame 3I of Fig. 9 longitudinally displaceable up or down in the direction of the pivot axis 33, that is, in the plane of the drawing. Instead, it is also possible to introduce a spherical mobility or a cardanic mobility for the pivot pin 33. For this purpose, for example, the pivot pins 33 are initially mounted in the cardan ring 34, and this is then mounted again perpendicular to the plane of the drawing in a second pair of pivot pins 35 (cf. the side elevation of the arrangement according to Fig. Io). This creates an arrangement in which the crank mechanism determining the piston movement of the axial piston transmission can be bent in any angular direction relative to the control surface 30 , so that any advance can be set, including a pivoting of the drive mechanism about a direction perpendicular to the main pivot axis. It is useful for this purpose, for example, to guide the right end of the swivel frame 3I by means of the reversing pin 38 in the desired manner, for example by means of a stone in a backdrop that can be given any height and any inclination. In Fig. Io, for example, the obliquely inclined gate 36 can be seen. If the gimbal ring 34 is replaced by a spherical surface in Fig. 9 and Io, another precaution must be used to transmit certain torques, e.g. a locking pin in the spherical surface, some other bracket on the swivel frame or a non-rotatable, correspondingly long stone in a correspondingly long backdrop 36.

As in the rest of the oil transfer to the swivel body goes on, is not essential to the invention. It can do this, for. B. a somewhat movable Pipe gland 37 in Fig. Io may serve or some other known means. In some cases it is also possible to arrange the frame 3I in a fixed manner and thus avoiding the need for moving pipelines. Fig. II shows, for example, a device such as that used in particular for motor vehicle drives suitable is. On the internal combustion engine flywheel z. B. the cardan joint 4o attached, which: drives the cardan joint 41 via a second shaft, which in turn first drives the transmission shaft 28 drives. This is similar to the version according to Fig. 9 mounted in a spherically movable manner in the gear housing 42, so that the universal joints are used 40 and 41 achieved any desired stroke setting of the primary part 43 of the transmission can be. The secondary part 47, which for the sake of simplicity has a common, control surface used on both sides, overdrives in a similar manner the cardan joints 44 and 45 to the rear axle 46 of the motor vehicle, with also here a spherical mobility allows any stroke adjustment. It will be advantageous the arrangement made so that for normal driving position only slight inflections of the various universal joints are required. How to do it in an inventive manner the holder of the shaft 28 can run on the primary or secondary part is in the oblique plan projection of Fig. I2 can be seen in more detail. For example one notices here two frame brackets 48 which support the shafts 28 with a self-aligning bearing lead and which in turn are held on the outer pivot pin 33. By having this frame 48 in the axial direction of the pivot pin 33, so Moves in the plane of the drawing in Fig. I2, can be made using the universal joints a flexion of the crank mechanism, at least to the required small extent, to achieve a perpendicular to the main pivot axis 33 and thus the required Influence of the advance etc. of the crank mechanism.

In many cases there is the possibility of an even further simplified one Version in which the trunnions in Fig. 9 are completely omitted. Fig. 13 shows the corresponding device in which the drive shaft 28 initially fixed and is immovably mounted in the housing, for example by two adjacent Radial bearing. The rest of the equipment corresponds to the design according to Fig. 9 and io, however, the outer trunnions and the outer gimbal are unnecessary, and in its place a simple, easily movable and designed for low forces is sufficient Holder with a pin 49, which is guided in a stone or a pan in the housing will. In the illustrated overall device of the engine, the main except for the described change in the shaft bearing of the design according to Fig. 9 is the same and as it is indicated there, the useful torque arises directly due to the play of forces between the drive shaft and its bearing in the hemisphere 32, so that the stud 38, which is used to adjust the stroke of the transmission and to influence its reversal serves, in the main is sufficient for the operation. To incidental To transmit forces, for example, one of the pipes provided with movable ones Stuffing boxes 37 through the pin 49 and a stone in a lid about only out in the drawing plane of Fig. 13.

This design allows a completely fixed mounting of the drive shaft 28 in two radial bearings, so that they can be moved so far apart to between them a precisely adjusted gear drive accommodate. One of the radial bearings can also be replaced by the one always in any one Form existing radial bearing of the drive shaft 28 in the hemisphere 32, for which about a connection of the hemisphere 32 with the outer body by a drive shaft 28 tube-like comprehensive and attached to the housing bearing sleeve 5o required is.

Instead of the link guide shown, similar-acting Handlebar arrangements kick. On the other hand, instead of the gimbal-like suspension according to Fig. g a holder of the swivel body on pegs with stones or rollers and appropriate scenes can be selected, as shown for example and schematically can be seen in the plan of Fig. I4. Here the swivel frame 31 is on three Out pins 52, which are guided in slideway-like slides or roller tracks. The scenes can become a single, easily adjustable frame frame in the housing 53, which can be equipped with appropriate precautions in order to Adjust the gearbox control settings as required while the gear is in motion can.

In all cases in which the operating pressure of the gearbox is not is subject to extensive fluctuations or the elimination of the noise and vibrations in a certain operating state, perhaps in medium Operating pressure, suffices, it is of course possible in place of the spherical or cardanic suspension achieved adjustability of the advance or the compression only a fixed flexion around the transverse axis with an axial piston gear or one Fixed displacement of the control pin perpendicular to the usual stroke adjustment device to be carried out for radial piston gears. These precautions, in particular for the radial piston gear will be described later in the designs according to Fig. I9 and 2o are of course only given a corresponding operating pressure for a certain operating pressure Compression or expansion of the resource. But in connection with a suitable one Choice of the angle setting of the control surface and the overlap carried out In many cases this is a significant improvement over this achieve the known design of such a transmission, in which simply the changeover times to certain angular positions of the main engine or, more precisely, to certain Angular distances from the dead center of the crank mechanism that drives the pistons, are bound and about the well-known procrastination of pressurization or discharge the piston is provided by throttle slots. The particular one described here Adjustment of the crank mechanism in the axial piston transmission, i.e. the pivoting or tilting around one to the actual pivot axis, which is the stroke adjustment serves, vertical axis, in the case of radial piston gears, the displacement of the control perpendicular to the usual stroke adjustment direction, results in a shift automatically the changeover times to the dead center of the crank drive, the very many operational requirements to some extent corresponds and at the same time is unsurpassed simple, since it as long as no adjustment of the transverse edge or transverse displacement required during operation is, only on an inclined assembly of the swivel frame or swivel body with axial piston gear or a lateral shift of the control pin with Radial piston gear comes out. This new type of gear arrangement does the trick automatically what happens with a gear that is not set according to this type could be achieved in that one of the reversing surface in the axial piston transmission or the reversing pin in the radial piston gear using a special device twisted so that this twist always with increasing reduction of the useful stroke becomes larger and assumes a value of 90 ° at zero effective stroke.

Such a twisting of the reversal is, however, as already in mentioned in the introduction, structurally very difficult to carry out, and the one given here particularly simple type of adjustment of the changeover times in dependence of the stroke size is accordingly a particularly expedient embodiment of the present invention.

The spherical mobility of the drive shaft or the drive ring can of course can also be replaced by a cardanic mobility, possibly under replacement of a fixed pin pair by means of an adjustable link arrangement in the direction of rotation. In the embodiment according to Fig. G, z. B. also the bearing of the drive shaft 28 can be fully assembled to the fixed housing 55, and then the guide the hemisphere 32 in the frame 31 are omitted and replaced by an outer one Ball mobility or gimbal mobility in the illustrated gimbal 34. This would then, in the simplest form, be a swivel device that can be moved in any direction found for an axial piston transmission, which have the advantages listed in the introduction the noiseless and low-loss work with any facility of the Axial piston transmission, also with an external frame suspension, would offer.

The arrangement can also be made so that for the main pivoting movement the actual trunnions remain and only for the mostly lower setting the lifting movement about an auxiliary pivot axis perpendicular to the usual pivot axis spherical mobility is provided. Fig. 15 shows a corresponding embodiment of the invention for external frame suspension. 28 is the drive shaft to which piston rods and pistons 16 that work in the cylinder block 15 are articulated. The cylinder block 15 is mounted in a frame 31, which is the usual external frame suspension has approximately in the tabs 56 which engage around the pivot pin 33. Instead of now the To fasten tabs 56 directly to the outer body of the associated radial bearing 57, the tabs are attached to an intermediate piece 58, which spherically supports the radial bearing carrier 57 includes. In this way, a stroke adjustment becomes perpendicular to the main pivot axis 33 allows, provided that the pipe stuffing box 37 accordingly something executed movably or the oil is passed through the spherical surface will. In this way, it is possible to use the usual swing frame 31 with the to make channels indicated by the arrow direction so far that the necessary correction of the reversal to achieve low-noise gear and avoidance unnecessary losses is allowed, even if the frame does not have internal suspension is carried out according to Fig. 13. Like the mounting of the frame within the spherical surface, for example with the help of an adjusting pin 38 and a backdrop, what is going on can also be provided for torque transmission is for Invention insignificant. Even if that forms the main object of the invention Adjustability of compression or expansion on the test field or their adjustability During operation, depending on the load conditions, in many cases more satisfactorily Way can be done by hand, it is an automatic adjustment with the pressure, possibly also with the stroke. The designs according to Fig. 13 and 15 are now particularly suitable for such an automatic setting to achieve, namely that you have the backdrop in which the guide pin 38 slides, making it adjustable accordingly. Fig. 16 shows a view of one appropriately furnished backdrop. The backdrop 6o is here on the right and left guided in elongated holes 61, for example on the shaft of a screw or a pin slide up and down. There is now a powerful adjustment cylinder on both sides 62 is present, which is actuated by the oil pressure of a transmission side through the pipeline 63 and its setting from the powerful, possibly also pre-tensioned Spring 64 depends. A stroke limiter 65, for example in the form of a screw, ensures that that even in the oil pressure-free state, the backdrop is not too loose, but for example there is only as much play as the air content of the operating fluid, the linkage play and similar influences, which cause an almost invariable compression or expansion require, corresponds.

By arranging such adjusting cylinders 62 on both sides one can Now achieve that the backdrop is appropriate depending on the meaning and the level of the oil pressure Carries out lateral shifts and also assumes inclinations and thereby any arbitrary Dependence of the compression on the stroke and the oil pressure including the direction of the oil pressure, so that a very complete automatic adjustment of the Compression or expansion to the changing operating conditions is achieved.

So far, the embodiment of the invention has been described for adjustable Gear parts, in particular adjustable primary parts. Of course it is also possible to use exactly the same facilities for gear parts in which a fixed or non-adjustable usable stroke is required. In this case the adjustability compression or expansion, for example in radial piston gears, through lateral displacement of the control pin perpendicular to its actual fixed eccentricity in front of you go or with the axial piston gear by swiveling the cylinder axis of rotation vertically to the fixed incline, which here causes the fixed useful stroke, similar to the Radial piston gear does this the fixed eccentricity. In these cases then also in place of the simultaneous adjustment of the useful stroke and the compression or expansion appropriately gimbaled or spherically movable execution of the Shaft bearing or the swivel frame bearing a simple cylindrical or journal bearing be set.

The transmission parts shown, for example, cardanic or spherically movable can of course also be hung up for two in a joint Arrange the housing in such a way that a complete gear set is created in which the the basic idea of the invention forming automatic or arbitrary adjustment the compression or expansion is carried out individually in both parts. the Gear parts can sometimes be put together in such a way that a common, A frame that can be tilted around an auxiliary pivot axis for both gear parts with sufficient Approximation results in the required adjustment of the compression or expansion. When radial piston transmission can, for. B. a common center pin, perpendicular to the usual eccentricity, the required compression or expansion influence effect, whereby it is also possible to carry out the main actuating movement of the transmission a particularly adjustable organ such. B. an eccentric adjustable to the center pin Drum or track. It is common with this type of gearbox the adjustment of the two adjustment movements, namely the stroke adjustment to one side-shifting drum or track and the compression or expansion setting on one or two laterally displaceable central pins, very advantageous because the latter Adjustment movement requires only small amounts and therefore usually already from the compensating couplings, which are required anyway, which connect the to cylinder stars or other gear parts mounted on the central journal with the or output shafts can be used. It corresponds to this already mentioned embodiment of an axial piston transmission, in which the stroke adjustment by pivoting the cylinder, the compression influence by a small Pivoting the drive shaft can be achieved.

Figs. 17 and 18 show, for example, a radial piston gear with a common compression and expansion setting for the primary and secondary parts. It consists of a central pin 72 common to both gear parts, on which a cylinder star 73 rides in a known manner on the right and left. The pistons of the transmission are driven in the known manner, for. B. via the wheel sets 74, which are eccentrically guided in the drum 75 to the center pin in order to achieve the required useful stroke movement. This is done, for example, in that the drums 75 are guided in the drum bearing support 76 so that they can be shifted laterally approximately in the plane of the drawing, the same device in the usual gears with common center pins on the right and left for the primary and secondary part in a similar manner Way is executed. To realize the variable setting of compression and expansion, which forms the basic idea of the present invention, namely a common adjustment for the primary and secondary part, the central pin 72 with the central pin carrier 78 is not completely fixed in the actual gear housing 77, but it is z. B. laterally displaceable approximately perpendicular to the plane of the drawing of Fig. 17, in that it can slide back and forth on the support surface 8o by small amounts, as shown again in Fig. 18 in a view of the center pin. A spindle 81 with traveling nut 82 is used, for example, to adjust the compression, with the handwheel 83 extending outwards enabling this lateral shift and convenient adjustment of the compression and expansion during operation. This is then a handwheel, which is to be arranged in a similar position to the handwheels 84 and 85, which are used in a known manner to adjust the drum bearing supports 76, but taking into account the fact that the main directions of displacement are perpendicular to each other. If one therefore wants to move all adjustment movements to the horizontal, one will resort to the means of not having the traveling nut 82 of the handwheel 83 engage directly on the central journal support 78, but on a wedge 86 on which the central journal support 78 rests and its back. and reciprocation provides the desired small up and down movement of the center pivot bracket. Or one or more screws or screw spindles are used which are somehow brought into the desired connection with the compression or expansion setting handwheel 83. In this way, it is possible to achieve a common and extremely simple implementation of the adjustability of compression and expansion according to the invention, in particular also during the gear, by means of automatic organs actuated by oil pressure, stroke or other operating variables in the radial piston transmission. Instead, it is often even easier to make the support of the drums 75 adjustable within the gear circle perpendicular to the direction of the useful stroke displacement of the drum.

Common adjustability can also often be achieved in the case of the axial piston transmission achieve compression and expansion in an extremely simple manner. Fig. I9 and 20 show, for example, such an axial piston transmission in plan and plan with two adjacent pivotable gear parts 88 and 89. This in the usual way with rotary stuffing boxes 9o equipped gear parts hang in a common auxiliary pivot frame 9I, the edge of which has a common compression setting causes the adjacent gear parts. Would you like this mostly is required to arrange the gear parts in the outer housing so that a stub shaft on the right, the other on the left leaves the housing, as shown in Fig. I9 and 2o is, it would however result that with the usual type of connection the side by side or rotary stuffing boxes lying in one plane go for the one gear part Correct compression and expansion influence for the second transmission part would be flawed. The pipe connections 92 must therefore be interchanged in such a way that that an overhead rotary stuffing box of one gear part with the lower rotary stuffing box the other is connected. Then it turns out that the at least in terms of correct compression influence comes about, and the approximately required different size of the same for the primary and secondary parts can be through the other known auxiliary measures, such as twisting, additional Special setting of the individual parts within the frame, for example in scenes 93 related to the frame, or one of the many special ones described here Measures to achieve without further ado. Here, too, the common compression can be influenced a handwheel 9q., which sets the common auxiliary swivel frame 9I, feed, so that, in addition to the actual stroke adjustment precautions, a handwheel is also used here for the compression or expansion setting or for the »blind stroke setting«, namely a common one for both parts.

Adjusting devices, which in this sense the compression setting, be it for several transmission parts together or for each separately, actuate, condition Strokes of the two pistons, which are at a right angle in their phase position to the Useful stroke movement are twisted. By analogy with known electrical devices and phenomena, this stroke setting can therefore, as already noted above, aptly may be referred to as a blind stroke adjustment, and this blind stroke adjustment or Influencing is one of the embodiments of the invention which deals with the arbitrary or automatic influencing of the expansion or compression processes concerned, in addition to the execution of the also possible and another embodiment the arrangement of auxiliary valves in or on the reversing device representing the invention, which cause a change in compression or expansion, or in principle equally executable mutable twisting of the reversal that is closely related with the blind stroke setting.

In the case of secondary shafts (so-called oil motors), this can also be done there advantageous influencing of the pressure in the displacement cells to be reversed the same tools can be achieved, namely with floating valves or with special pumping stations or with canting or transverse shifting, for example, provided here Stroke adjustment devices, such a stroke adjustment device under Circumstances only influencing the pressure in the displacement cells to be reversed can serve.

The details of carrying out the invention as presented here at numerous Examples are described are not essential to the invention itself. Essential is a device that influences the pressure in the displacement cells to be controlled, unaffected through mass effects, for example with the help of lighter, fast-acting valves, special pumping stations or a stroke adjustment of the transmission part perpendicular to the usual adjustment device.

Claims (7)

PATENT CLAIMS: I. Hydraulic displacement device, pump or motor, in particular for gearboxes, with a reversing device through which the displacement spaces are switched from the suction to the pressure side and vice versa, and with a device by means of which the pressure in the displacement spaces, While these are closed off from the suction and pressure side, their size is influenced in addition to the pressure changes caused by the changes in the displacement spaces caused by the design of the device, characterized by an additional influence of the pressure curve free of mass effects by the extraction or introduction of oil flows the cylinders or in the same with the help of low-mass valves or special oil pumping stations or oil motors. 2. Device according to claim I, characterized by pumping stations or oil motors, which are accelerated by according to the number of cylinders the gear parts are driven and t, by appropriate angle adjustment allow the compensation of the main movement of the gear pistons and also after Enable a selectable pressure control as required. 3. Device according to claim I, characterized by an adjustability of the lifting mechanism perpendicular to the direction the movement for influencing the stroke by means of an adjustable shift of the reversal perpendicular to the effective stroke adjustment direction for radial piston gears or by a adjustable tilt of the pivotable or pivoted part perpendicular to the Effective stroke swivel axis in the axial piston transmission. 4. Device according to claim 3, in particular for axial piston gears, characterized by ball mobility or cardanic Mobility of the engine part used to adjust the lift (3I in Fig. G). 5. Device according to Claim 4, characterized by a suspension that is movable in all directions of the swivel body of a gearbox with a fixed shaft (28 in Fig. g) and tiltable Cylinders (I15 in Fig. G) inside the housing. 6. Device according to claim 4, characterized by the fixed bearing of the drive shaft (28 in Fig. I15) and on all sides movable setting of the swing frame body which determines the cylinder inclination (3I in Fig. I5). 7. Device according to claim 3, characterized by switching elements (94 in Fig. I9 or 83 in Fig. I8) for joint actuation of the compression or expansion movements for several gear parts. B. Device according to claim 7 for radial piston gears, characterized by a switching element (83 in Fig. I8) for adjusting the central pivot (72 in Fig. I7) or the common central pivot a double gear perpendicular or inclined to the direction of the eccentric adjustable Piston raceway or piston guide drum. G. Device according to claim 7 for axial piston gears, characterized by a common frame (g3 in Fig. 2o) or a common Housing for joint actuation of the compression or expansion processes for several gear parts. Io. Device, especially for axial piston gears, according to Claim 3, characterized by a laterally movable in the direction of the pivot axis Gear housing (42 in Fig. II) in connection with a movable shaft coupling (q.1 and qq. in Fig. ii) to influence the pressure development in the displacement spaces without delay due to mass action, while this is from the suction and pressure side Are completed. Publications considered: Swiss patents No. 44 448, 226 o85; U.S. Patent No. 2,288,768.