DE1528941A1 - Capsule pump or motor - Google Patents

Description

The invention relates to a capsule pump with a hydraulic device for controlling the blades, which are generally referred to in the art as "three-area" capsule pumps (vane pumps of the "three-area" type) and relates to a device by means of which damage to the device constituting the third surface is caused by Impacts or knocks during operation are prevented.

A capsule pump comprises a rotor with several radial movable vanes which are arranged in slots that are equiangularly spaced around the circumference of the rotor are distributed; ^ These wings are related to the cam surface of a The stationary stator or I-cam ring surrounding the rotor in

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With the wing control principle acting on surfaces, a certain force is obtained for pushing or moving outwards the wing.

The liquid pressures acting on two of the surfaces assigned to each wing are essentially the same, but act in opposite directions, and the forces resulting from these pressures consequently have a tendency to work against each other. The first surface includes a surface at the radially outer end of each wing and is a Exposed to pressure that dangles the wing inwards in its slot. The second wing surface includes a surface on the radial inner end of the wing, which is subjected to the same pressure as the first surface, but which is in the opposite direction Direction acts and pushes the wing outwards in its slot.

A third surface associated with each wing is also exposed to a liquid pressure which the wing pushes outwards. Apart from the centrifugal force, this pressure acting on the third surface forms the control · »· force that pushes the wing outwards, regardless of irregularities in the profile or the curvature of the surface

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of the cam ring to effect a fluid seal between the outer end of the vane and the cam ring and keep it upright.

The present invention relates to improvements in capsule pumps of the "three-surface" type as disclosed in US Pat. No. 2,832,293 dated April 29, 1958 and in application 296,017 filed July 18, 1963.

Capsule pumps of the "three-surface" type, on which the invention relates to comprise a rotor having an internal pressure chamber and a pressure differential associated with each wing actuated pin or piston, each slidably mounted in a bore that defines the pressure chamber cuts and leads to the wing. The pressure prevailing in the chamber and acting on the piston forms that on the Third force acting on the surface that holds the wings outward. Whenever the pressure in the chamber affects you If the value threatens to drop below the pressure prevailing in a high-pressure zone, this chamber is channeled from the High pressure zone of the pump supplied with pressure.

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The device forming the third Fleche can, for. B. be a full piston according to patent 2,832,293 or preferably comprise a piston which is provided with an axial bore which is connected to the inner end of the corresponding Wing forms a check valve to the DruckflÜssigkeitsströ flow from the pressure port of the pump into the pressure chamber connecting the inner ends of all pistons regulate. Whenever the external pressure acting on a piston follows the pressure prevailing in the internal chamber and the piston exceeds the outside pressure, liquid flows from the slot through the longitudinal bore in the piston into the chamber, until a pressure equalization is essentially achieved. This pressure acts equally on all pistons and the wings, to keep the wings in engagement with the cam surface.

Although "three-surface ⁿ -capsule pumps of the type mentioned above have brought about a significant improvement in operating performance, these devices sometimes suffered internal damage during operation. in particular a "mushroom-like" deformation of the inner ends of the pistons and sometimes the rupture of the wall opposite the piston and forming the pressure line in the runner. Probably occurs

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this damage occurs when, when setting up the pressure in the pressure port of the pump all of a sudden increases.

So far, no satisfactory way is known to mitigate the impact of the pistons on the bottom of the bores or slow down. It is therefore an object of the invention to provide a device by means of which this source of damage can be canceled for the piston or the pressure chamber wall.

The invention is based on the knowledge that the deleterious effect of a sudden, steep increase in pressure can be bypassed in the pressure port of the pump by having a valve device for each piston forming the third surface assigned, so that when the external pressure rises by the gradual closing of the valve device the movement of the piston towards the pressure chamber is slowed down. It has also been shown that particularly advantageous

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Results are obtained when the piston bore The amount of liquid flowing into the pressure chamber is progressively reduced as the piston approaches the component, which limits its movement in the bore.

The invention is explained in more detail below with reference to drawings of a preferred embodiment.

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Fig. 1 is an Axialsclinitt through a vane pump of "Three-face" type with a preferred device according to the invention;

Fig. 2 is a section in the radial or transverse direction along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged view of a single wing shown in FIG. 2.

The Kapselbzw shown in the drawings as an example. Vane pump comprises a housing of a casting 1 with a generally cylindrical inner chamber and a End cap 2 is formed which has a cylindrical extension 3 which extends into the end of the body and is sealed by an O-ring 4 therein.

The end wall 5 of the body opposite the end cap 2 is provided with a bore through which the actuating shaft 6 of the pump extends. The shaft 6 is in this bore rotatably supported by a bearing (not shown), the bearing being fixed in the bore for axial movement. The socket 6 extends from the body 1 into the end cap 2

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in and is in it by one within a middle Boiming in the end cap mounted needle bearing 7 rotatable supported.

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and is in duroh one within a center hole Needle bearing 7 mounted in the end cap is rotatably supported.

The cylindrical extension 3 of the end cap is machined in such a way that a flat inner surface or contact plate is formed which is in contact with a side surface or a radial surface 8 of a cam ring or a cam drum 9 is clamped. At this point it should be pointed out that the cam drum itself or the housing with the cam drum together are sometimes referred to as the stator.

A liquid inlet 10 extends radially into the Body 1 and stands with a pair of inner ring channels 11, 12 in connection that surround the interior cavity within the body. These annular channels 11, 12 distribute liquid from Inlet 10 to suction openings described below.

in
The Nookentrommel 9 is / radial direction by a

supported annular rib 13, which is formed in the body 1 between the annular channels 11, 12 _: . The cam drum 9 surrounds a rotor 34 which is fastened on the shaft 6 by a wedge 15, which enables the correct running alignment between the rotor 14, the flat surface of the cylindrical extension 3 and a Baokenplatte 16 * The rotor H has several

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rere radial Schiit «« 17, in each of which a plugel 18 is appropriate "

The hook drum 9 has a Hookenfläohe 19, whose Profile is designed in such a way that a balanced construction is created, that is, diametrically opposed to each other- '· Lying low-pressure or suction zones 20, liquid transition zones 21, high-pressure or discharge zones 22 and detachment zones 23 are formed between the look area and the runner 14 (see 71g 2) from a first pair of bows with the same baths that extend over the transition zones 21 extend, and partly from a second pair of arches, the baths of which are smaller than those of the first Pair of arches and which extend over the abioht zones 23 'These pairs of arches are tied together by squatting surfaces, which spread over the low pressure or high pressure zones20 or achieve. '

You Baoken plate 16 is processed so that a smooth flat radial surface formed on that side which is applied to the Noekentroffline 1 9. In addition, the Jaw plate has a central bore 24 on the τοη a cylindrical projection 25 is surrounded, which look into the bore

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in the wall 5 of the body 1 extends and is duroh therein an O-bing 26 sealed. The outer cylindrical surface of the jaw plate 16 is opposite to the body 1 duroh an O-bing 27 sealed.

You cheek plate 16 is in body 1 in the axial direction movlioh and is duroh liquid pressure, which from the Hoohdruokzone 22 duroh passages 28 and 29 in a pressure chamber 30 is transmitted between the body and the outer surface 31 of the jaw plate, checked against the rotor 14. The baking plate acts like an axially movable, non-rotatable piston which is exposed to the pressure that is present in the chamber 30 Liquid to keep the piston in singular engagement with the crouching drum 9

The inlet 10 stands above the ring channels 11, 12 surrounding the Noekentroamel 9 with suction and inlet openings in communication 180 ° apart. Two suction ports, one of which is shown at 50 in FIG is, are formed in the jaw plate 16 and are rom

Channel 12 is supplied, while two more, not shown suction

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openings are formed in the end cap 2 and from the channel are supplied · These suction openings in the end cap or in the Baoken plate are identical in shape and are in axial alignment with the suction zones 20 between the runner

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and the squatting surface 19. Each suction opening has a branch; the opening of one of these branches is shown at 51, across which the suction opening with the inner ends 32 of the slots 17 in the rotor 14 as well as with the inlet zones 20 in connection stands"

As shown in Fig. 1, the end cap 2 comprises two each other diametrically opposite, crescent-shaped discharge or pressure openings 52, 52, which are essentially 90 ° from the Suction openings are remote · Similarly, pressure openings 56, 56 are formed in the jaw plate 16 which are axially with the pressure zones 22 and the openings 52 in the end cap cursing. Each pressure port 52 and 56 has branches 54 with the inner ends 32 of the slots 17 in the runner in connection when these slots move past the openings will. The pressure openings 52 are via a channel 35 in the End cap 2 connected to a liquid outlet 34.

In the direction of the rotor movement (by the arrow in Fig. 2 shown) the squatting surface 19 gradually recedes from the circumferential surface of the runner 14 over the suction zones 20. In the transition zones 2t, the cam surface 19 has a substantially constant radial distance from the rotor, and over Approaching the delivery zones 22, see the Nookenf pool al 1-

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gradually back to the runner 14 and comes in the sealing zones 23 in the immediate vicinity of the circumferential surface of the runner 14 between successive wings cells are formed to transport the fluid, and when these cells are in the Increase movement of the wings 18 through the suction zones 20, the liquid coming from the suction openings 50 will enter these cells sucked in. The liquid is inevitably from the Displaced cells when their volume is reduced when moving the wings through the pressure zone 22, so that a pumping action is caused.

Each wing 18 is provided with grooves 36 in its Outer edge and are formed in opposite side edges. One or more channels or bores 37 are also present in each wing and provide a connection between the outer groove 36 of the wing and the inner one End 32 of the slot. The grooves 36 and channels 37 ensure that the fluid pressure acting on the first surface or on the outer end surface or tip of each wing at any time through the on the second surface or on the inner one The pressure acting on the end face of the wing is essentially balanced.

When the pump work with great efficiency should, it is necessary regardless of the changes in the

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Curvature of the cam surface constantly sealing engagement to get lined up between the wing tips or «, the outer end surfaces and the Uockenflache 19. To this end one or more radial bores or cylinders 38 are formed in the rotor 14, each extending from the inner end of the slots 17 extend inward. The bores 38 are connected to an annular pressure chamber 39 at their inner ends in connection, which is partly provided by an in the runner

educated
Groove b @ gaxeamte · Liquid can only flow into the pressure chamber and out of it through the radial bores 38 · As FIG a fraction of the diameter of the bore 38. The groove in the runner, which partially defines the chamber 39, is closed by a sleeve 40 which is fitted with a close fit in an axial recess in the runner and is sealed therein. This annular chamber or conduit 39 connects the inner ends of the radial bore 38 with one another.

A generally cylindrical pin or piston valve member 41 is received in each radial bore 38.

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An axial bore 42 is provided in each piston 41, and the pistons are slidably but closely fitted in their bores 38 so that the exit of liquid is longitudinal

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the outer wall of the pistons is negligible or minimal · The outer end of each piston 41 is conically tapered at 43 and together with the flat inner edge 44 of each plug 1Θ forms a valve. The application of fluid to the radial bore 38 is regulated by the balance of forces between the pressure of the fluid acting inwardly on the conical bevel 43, which tends to open the valve, and that pressure force which results from the pressure in the K _a mmer 39 which together with the centrifugal force and strives to close the valve. The length of the piston 41 is so selected that the pistons can move independently of the position of the sash in the associated slot in and out of engagement with the flat inner edge 44 of the blade 18 "The cuff 40 forms a wall that the inwardly Can limit movement of the piston in the corresponding bores. As FIG. 3 shows, the slot ends 32 are preferably arranged in the radial direction in such a way that they limit the inward movement of the vanes before a vane can press the corresponding piston 41 against the sleeve 40.

As a piston moves inward and approaches the sleeve 40, the inner end 45 of the piston forms a valve with the entrance 46 of the chamber 39 to the bore 38. It is

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It can also be seen that the lower end surface of each piston is preferably chamfered as shown at 47. When calibrated As the piston approaches the cuff 40 very closely, the inner end of the piston 41 acts with the cuff 40 and the bore 38 together in such a way that a chamber is formed below the piston 41 from which the liquid is only relatively limited Amount can escape

During operation of the device according to the invention, the valve 41 »44 at the outer end of the piston acts like a check valve. When the pressure acting on the conical bevel 43 of the piston 41 at the inner end 32 of a slot exceeds the centrifugal force acting on the piston and the pressure force prevailing in the chamber 39, the piston is moved inwards in its bore 38, and the valve 41, 44 opens calibrated - The liquid located in the inner end 32 of the slot 17 flows inwards through the bore 42 to the chamber 39 and, depending on the situation, restores the pressure in the chamber, maintains it or increases it to compensate for the pressure the joins in the sense of opening of the valves 41, 44 acts · this operation, when the slit _f 17 passes through the pressure zone because the pressure in this zone 22 pressure is

higher

usually a little bit s3Äftd «digea% A wing 18 passes through a suction zone 20, βο exceeds the pressure prevailing in chamber 39

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the one in the opposite direction on the end 43 of the piston acting pressure, and the piston is held in contact with the inner edge 44 of the plügelB to close the valve 41,44.

As already mentioned, it has been found that if the pump delivery flow is suddenly blocked, a steep rise in pressure occurs which is transmitted back into the pump through the outlet 34 and from there into the pressure zones 22 and the slots 17. It is assumed that under these circumstances the pressure of the hydraulic fluid far exceeds the pressure in the chamber! the valves 41 _t 44 open very rapidly. The liquid under high pressure in the slits strives to flow rapidly through the bore 42 into the chamber 39 bu in order to compensate for the pressure prevailing there. Obviously, if no design according to the invention is provided, the rapidly flowing liquid will drag the pistons 41 radially inwardly and cause the pistons to impact the collar 40 or other abutment wall, thereby damaging both the collar or wall and the pistons.

In a pump having the features according to the invention, this harmful effect is avoided. If the Piston 41 of the cuff 40 or other wall forming the bottom of the bore 38 approaches: it forms with the narrow inlet

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a valve 45, 46 in the chamber 39. The flow of the liquid into the chamber 39 is thereby throttled. The area of the opening 46 gradually decreases when si oh the piston approaches the cuff until the valve 45 »46 is almost closed · This reduces the force causing the movement of the piston 41 and stops it before the piston hits the Cuff 40 meets “In addition, the one below the End surface 47 of the piston 41 οincluded® liquid & oil Shock absorber and thereby slows down the movement of the piston even more and prevents damage has a braking effect that prevents a sudden Rise in the outside pressure the piston 41 or the cuff or other wall fixtures damaged

While the pistons of the devices that do not have the improvement according to the invention are sometimes attached to their interior Ends are deformed mushroom-shaped and / or punch holes in the cuff, it has been shown that these effects are practically excluded by the device provided according to the invention.

It is clear to the Jaehmann that the invention also applies to other embodiments of vane pumps or rotary lobe pumps.

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Motors such as those described in U.S. Patent 2,832,293, inventor Adams et al., can be used are by providing a valve device which restricts the flow of liquid from the bottom of the piston and interrupts when the piston approaches the wall device forming the end.

As already mentioned at the beginning, the improved hydraulic fluid transmission devices can according to the description can also be used as motors. If they are working as a motor, there may be no fluid pressure when they start operating present that operates the door control device, if the wings are not in contact with the cam ring from the start. For this reason springs can be provided be to create a light initial force holding the wings outward.

Claims

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Claims (2)

DR.IHG. F. WtFESTHOFF 8 MUNICH ΘΟ DEJPJUIHXf. β. PIJXS SOHWEIGERSTRASSE S TELEKOM SS.OB Bl PItOTBOTPATKKT 1A-32 262 Claims (1 Λ capsule pump or motor with a radial slot for the rotor having blades, which is housed in a chamber, which low pressure and high pressure ports and includes each peripheral wall, each wing in sealing contact with the peripheral wall, and each first surface which is exposed to hydraulic pressure which urges the vane radially inward in its slot, and also has a second surface exposed to hydraulic pressure which the wing in its Slot pushes radially outward, and with a device for. Equalizing the on the first and second surfaces each Wing acting fluid pressures and each wing also having a third, the first surface opposite Comprises surface area, each of which is assigned a hydraulically actuated device, around the corresponding Wing at least when he is at the depression opening is moved past to urge radially outward in its slot and with a pressure chamber all these hydraulically actuated devices via individual branches connects with each other, and with a device by means of the Pressure fluid from the high pressure port to the pressure chamber is 90983770620. is directed, characterized in that the respective hydraulically "actuated devices (41) are assigned to pressure-responsive valves (45, 46), which with the corresponding individual branches interact in such a way that that the connection between the hydraulically operated devices and the pressure chamber (39) is always progressive is throttled when the pressure prevailing in the pressure chamber drops significantly below the pressure that acts on the hydraulically operated devices and tries to push the wing outwards. 2. Rotor arrangement for a hydraulic vane pump, characterized by a rotor with vanes, which are reciprocally mounted in vane slots, one within the rotor assembly forming a pressure chamber Device by means of which a compressive force is exerted on all wings in order to push the wings outwards in the slots, a bore assigned to each wing, through which pressure fluid is fed into the pressure chamber, a pressure-actuated Valve with a movable valve element mounted in each bore opening to allow liquid to enter the chamber can flow, and being through the movable valve element 909837/0620 a longitudinal channel extends through which the liquid flows when it moves towards the chamber with the valve open, and by a stop which inevitably limits the opening movement of the movable valve element, and by a shock-absorbing device which reduces the speed of opening movement of the movable valve element as it approaches to the stop gradually reduced, so that the possibility of damage to the stop and the movable valve element, which would enter when the valve opened rapidly, is reduced becomes β 3 impeller arrangement for a hydraulic vane pump, marked by a runner with wings that are mounted so that they can move back and forth in wing slots, a piston associated with each wing, each in a radial bore in the rotor is slidably mounted, one within the. Rotor assembly forming a pressure chamber device, whose prevailing pressure in it cooperates with the piston in such a way that a force is exerted on the wings that the Presses wings in the slots outwards, a passage device for supplying pressure fluid into the pressure chamber, means limiting the inward movement of each piston in its bore, and by a valve which -of and between each piston and which delimit the pressure chamber- - 4 909837/0620 zenden device is formed, the valve by the inward movement of the piston gradually closed as it approaches the limiting device will. 4 «rotor arrangement for a hydraulic © vane pump, characterized by a runner with wings which are arranged to be movable to and fro in wing sole seats are, a piston assigned to each wing, each slidably mounted in a radial bore in the rotor is, a transversely extending annular pressure chamber within the rotor assembly, bores extending from the corresponding wing strands radially inwards. stretch and angularly intersect the chamber, a spigot valve element slidably mounted in each bore by pressure fluid in the chamber from the chamber is pushed away, each valve element having a longitudinal bore through which the pressure fluid as it moves must flow towards the chamber, one wall of the chamber corresponding to the movement of the corresponding valve element the flow of fluid through the bore is inevitably limited, and duroh a valve that goes from and between the end of the valve element and the bore through which the liquid must flow in order to get into the chamber is formed, where- - 5 909 8 37/0620 When the valve element moves in accordance with the flow, the hole may gradually close the valve when the valve element approaches the wall 5 e rotor arrangement for a hydraulisch® flying hedgehog pumps, characterized by a mu.fer.with .wings, which are attached to and fro in winged sleeves, a piston assigned to each wing, d © r;} e «» while slidingly mounted in a radial bore in the rotor, "an annular bruekkaffiffi" ·? within the array running it, bores inwardly extend VMA the chamber in Wink @ labständ © n Toneinander sehneidtn, a slidably mounted in each bore nozzle element _s which is radially from the corresponding Flügelsehlitzen by pressure fluid in the sammer the chamber ~ τοη pushed away , each valve element having a longitudinal bore through which the liquid must flow during its movement in the Eichtujig sur chamber, a wall of the chamber inevitably limiting the movement of the corresponding valve element and the flow through the bore. by a Yentil which elements and between the end of the Tenti! and the bore through which the liquid must flow _s to reach the cashier, wirdj formed, wherein the movement of the valve member according to the flow through the bore of the 909837/06 2 0 Valve as the valve approaches the wall gradually closes, and through a facility that. forms a shock absorber within the bore, which resists the rapid movement of the piston towards the wall « 6c vaned hydraulic fluid transfer device with a rotor with several blades, which are mounted in blade slots so that they can move relatively radially a post having a cam surface with which the outer ends of the vanes can engage, and with radially movable, pressure actuated, hollow piston valve elements associated with each wing for acting on the wings apply a force which they move outwardly into engagement with the cam surface, characterized in that, that each piston is assigned a pressure inhibiting device, by means of which the speed of the valve opening movement gradually slowed down in response to a large pressure differential on opposite sides of the piston will 7 rotor arrangement for a hydraulic vane pump, g e k e η η ζ e leaned by a rotor with vanes, which are mounted so that they can move back and forth in wing slots, one extending from each wing part inwards to the axis of the - 7 -909837/0620 Runner extending radial bore, one in each radial Piston slidably received and provided with a longitudinal bore, an annular chamber provided in the rotor, which intersects the bores, the pistons with the corresponding wings forming valves that allow the inflow of Hydraulic fluid from the wing sole strands through the longitudinal bores in the annular chamber control a device that controls the movement of each piston according to the flow through it the bore in the direction of the chamber necessarily limited, each piston cooperating with the chamber in such a way that a valve is formed through which the flow coming through the bore must flow in order from the bore in the piston in to enter the chamber, the valve being approached by the movement of the piston in accordance with the flow through the bore of the piston to the limiting device • is gradually closed, with the chamber at its intersection with the holes has an axial dimension that is smaller than the Durohmesser of the hole. 8 rotor arrangement for a hydraulic vane pump, characterized by a runner with wings that can be moved back and forth in wing slots are, a radial bore extending inwardly from each vane slot toward the axis of the rotor, one slidably received in each radial bore, with a - 8 909837/0620 piston provided with a longitudinal bore, a piston provided in the rotor, ring-shaped chamber that surrounds the bores, whereby the Pistons with the corresponding wings form valves that the Inflow of pressure fluid from the wing slots through the It controls longitudinal bores in the annular chamber, a device that controls the movement of the piston in accordance with the flow inevitably limited by the bore in the sight of the chamber, each piston interacting with the chamber in such a way that a valve is formed through which the fluid flowing through the bore must flow in order to be removed from the bore in the piston to get into the chamber »whereby the valve is activated by the movement of the piston in accordance with the flow through the bore Approaching the piston to the limiting device is gradually closed, and with the chamber at its point of intersection with the bores having an axial dimension smaller than the diameter of the bore, and each piston having a having inner end surface which forms a valve opening with the chamber, the surface being abeohraped and with the Limiting device cooperates in such a way that a shock absorber is formed when the end face approaches the limiting device. 9 · Rotor arrangement for a hydraulic vane pump ·, I mark η e t with a rotor - 9 -909837/0620 Wings that are movably attached in wing sole seats are, a device which forms a double valve element associated with each wing and in a radial Bore is slidably mounted in the rotor, a device forming a pressure chamber within the rotor assembly, by means of which a pressure force is exerted on all wings, which presses the wings outwards in the slots, one for each wing associated, valve-provided bore, by means of which pressure fluid is conveyed into the pressure chamber, each Bore a longitudinal channel in the corresponding double valve element comprises, through which the pressure fluid flows upon entry into the chamber, a device forming a stop, the movement of each double valve element according to the Flow through the bore provided therein inevitably limited, and a Ventileinriohtung that from and between the Double valve element and the runner is formed, through which the liquid must flow in order from the channel to the chamber arrive, the valve device by the movement of the ■ '..' - iJ- v '.: · ■ ·, ι' ■ ■: ■ - - ■ .....- ■■■ .- ■. - '■ ■. '' ■ ■. Double valve element corresponding to the flow through the channel when the double valve element approaches the limiting device is gradually closed » '■' S 10 · Rotor arrangement for a hydraulic vane pump, g e k β η η ζ e i c h η β t by a rotor with - 10 -909837/0620 15 2 8 9 - w- ]? lie In, which are mounted to move back and forth in wing slots, a piston assigned to each wing, which is movable in a radial bore extending inward from the wing slot in the runner, a device forming a pressure chamber by means of which a compressive force is applied to all piston is exerted that presses the pistons outwardly into contact with the vanes, said chamber connects all the radial bores in the rotor within the piston with each other, and by a plurality of Yentileinrichtungen, which are each formed by and between the rotor and the respective piston, the flow between each bore and the chamber goes through the corresponding valve device, which is gradually closed by the inward movement of the piston in its bore in the direction of the chamber 909837/0620