阅读说明：本技术 流动优化叶片泵 (Flow optimized vane pump ) 是由 塞巴斯蒂安·西德尔 于 2018-11-15 设计创作，主要内容包括：本发明涉及一种用于输送液体(尤其是粘稠的油)叶片泵,包括：转子(2),其具有其中容纳可滑动叶片(3)的滑动槽(23)并且可相对于转子半径(r)缩进；泵壳体(1),其具有容纳转子(2)的泵室(10)；及入口(5)和出口(6),所述入口(5)和出口(6)至少朝向转子(2)的端侧开放而进入泵室(10)；其中围绕转子(2)的圆周,朝向滑动槽(23)突出的径向抬升部(21)形成达到可缩进叶片(3)的任一侧的转子半径(r),并且在径向抬升部(21)、径向凹部(20)相对于转子半径(r)发生凹陷。在径向抬升部(21)内,在入口(5)和出口(6)向其开放的转子(2)的至少一个端侧,形成有凹部(4),该凹部(4)提供用于减小叶片室中的压力峰值的旋转伺服控制几何形状。(The invention relates to a vane pump for conveying liquids, in particular viscous oils, comprising: a rotor (2) having a sliding groove (23) in which the slidable vane (3) is accommodated and being retractable with respect to a rotor radius (r); a pump housing (1) having a pump chamber (10) that houses a rotor (2); and an inlet (5) and an outlet (6), the inlet (5) and the outlet (6) opening into the pump chamber (10) at least toward the end side of the rotor (2); wherein a radial lift (21) projecting toward the sliding groove (23) forms a rotor radius (r) up to either side of the retractable blade (3) around the circumference of the rotor (2), and a recess (20) is formed in the radial lift (21) with respect to the rotor radius (r). In the radial lift (21), at least one end side of the rotor (2) to which the inlet (5) and the outlet (6) open, a recess (4) is formed, which recess (4) provides a rotary servo control geometry for reducing pressure peaks in the blade chamber.)

1. A vane pump for conveying liquids, in particular viscous oils, comprising:

a rotor (2) having a sliding groove (23) in which a slidable vane (3) is accommodated, and the slidable vane (3) being retractable with respect to a rotor radius (r);

a pump housing (1) having a pump chamber (10) surrounding the rotor (2), the inner contour (12) of which comprises a hollow cylinder which is eccentric to the rotor radius (r) or has a radial elevation relative to the rotor radius (r) at least in the direction of rotation of the rotor (2); thereby making it possible to

The vane chambers (30), which respectively occupy the rotating local volume of the pump chamber (10) located between two adjacent vanes (3), undergo an increase in volume and a decrease in volume as a function of the radially inner contour (12) of the pump chamber (10); and

an inlet (5) in the rotation angle range of the volume increase and an outlet (6) in the rotation angle range of the volume decrease, the inlet (5) and the outlet (6) opening into the pump chamber (10) at least towards an end side of the rotor (2); wherein

On the circumference of the rotor (2), radial elevations (21) projecting towards the sliding groove (23) form a rotor radius (r) on either side of the slidable vane (3), and between the radial elevations (21) a radial recess (20) is recessed with respect to the rotor radius (r);

the method is characterized in that:

a recess (4) is formed in the radial raised portion (21) on at least one end side of the rotor (2) to which the inlet (5) and the outlet (6) are open.

2. A vane pump as claimed in claim 1 wherein

The recess (4) comprises at least two adjacent radial portions (41, 42) in the radial direction of the rotor (2), the radial portions (41, 42) differing from each other in the depth (d) of the recess relative to the end-side surface of the rotor (2).

3. A vane pump according to claim 1 or 2, wherein

The radial portion (41) of the recess (4) located more radially inwards of the rotor (2) comprises a greater depth (d1), and the adjacent radial portion (42) of the recess (4) located more radially outwards of the rotor (2) comprises a lesser depth (d 2).

4. A vane pump according to any one of claims 1 to 3 wherein

The contour of the recess (4) or a radial portion (41, 42) of the recess (4) is constant in the circumferential direction of the rotor (2).

5. A vane pump according to any one of claims 1 to 4, wherein the recess (4) or radial portions (41, 42) of the recess (4) form a groove having a rectangular, V-shaped or U-shaped profile.

6. A vane pump according to any of claims 1 to 5, wherein the distance (c) between the mouth of the inlet (5) and the mouth of the outlet (6) into the pump chamber (10) substantially corresponds to the distance between two vanes (3).

7. A hydraulic pump for generating a constant pressure for a hydraulic actuator or driver, comprising a vane pump according to any one of claims 1 to 6.

8. The hydraulic pump of claim 7, further comprising:

variable displacement pump geometry, wherein the distance between the rotor radius (r) and the inner contour (12) of an eccentric hollow cylinder or a radial lift of the pump chamber (10) can be set by means of an actuator (7).

9. Use of the hydraulic pump according to any one of claims 7 or 8 as a driving source in a hydraulic power steering system for a vehicle.

Technical Field

The invention relates to a flow-optimized vane pump with reduced pressure pulsations in the vane chamber.

Background

In contrast to centrifugal pumps, rotary positive displacement pumps (e.g. vane pumps) in principle generate pressure pulsations which arise from the sequence of feed and discharge cycles during one revolution of the pump shaft. The pulsation is related to the initial pressure of the pump during load changes and flow characteristics of the flow being delivered from the inlet into the vane chamber and from the vane chamber to the outlet, and also to the internal pressure of the simultaneously closed vanes. In general, pulsating pressure in a closed space or circuit of a hydraulic system causes problems such as a decrease in durability of a sealing point or generation of noise with a sensible resonance.

Disclosure of Invention

It is an object of the present invention to provide an alternative optimization of the pump geometry, which also results in a reduction of pulsations inside the vane chamber of the vane pump.

This object is achieved by a vane pump having the features of claim 1.

The vane pump for conveying liquids, in particular viscous oils, comprises: a rotor having a sliding groove in which a slidable vane is accommodated and the vane is retractable with respect to a radius of the rotor; a pump housing having a pump chamber surrounding a rotor, the inner contour of the pump chamber comprising a hollow cylinder which is eccentric to the rotor radius and/or has a radial elevation relative to the rotor radius at least in the rotational direction of the rotor; causing vanes which respectively occupy a rotary part volume of the pump chamber between two adjacent vanes to undergo a volume increase and a volume decrease based on a radial inner contour of the pump chamber; and an inlet in a rotation angle range in which the volume increases, and an outlet in a rotation angle range in which the volume decreases, the inlet and the outlet opening into the pump chamber at least toward an end side of the rotor;

wherein on the outer circumference of the rotor, a plurality of radial raised portions projecting toward the sliding groove form a rotor radius on either side of the retractable vanes, and between the radial raised portions, a radial recessed portion is recessed with respect to the rotor radius.

The vane pump is particularly characterized in that: at least one end side of the rotor, towards which the inlet and the outlet open, a recess is formed in the radial elevation.

According to the invention, for the first time a dynamic servo control geometry is applied in a vane pump, which geometry is achieved by modifying the rotary control plate at the vane pump rotor, as explained below.

The recess on the end side of the rotor radial lift forms a relatively large communication cross section of the space of the vane chamber which is extended in time, initially open to the outlet opening and subsequently to the inlet opening, over the range of the angle of rotation between the outlet opening and the inlet opening, in which the rotating vanes move past the pump chamber in a sealed manner. Thus, the fully enclosed volume displacement (i.e. in particular the enclosed volume change) is shortened or omitted, thereby effectively reducing the generation of short term high pressure peaks in the rotating vane chambers.

Even if the distance between the inlet and the outlet is selected on the basis of the size of the vane chamber located between the inlet and the outlet so as to minimize the effective distance of the enclosed volume displacement or volume change of the vane chamber, there is still a small cross section limiting the pressure increase within the vane chamber at the point in time of the optionally simultaneous volume closure and volume opening of the end-side vane chamber in the rotor.

At the same time, based on the specified viscosity of the medium and the size of the recess, a sufficient sealing effect is obtained at a small section of the recess, thereby preventing a hydraulic short circuit between the inlet and the outlet during crossing of the vane chamber and suppressing a decrease in volumetric efficiency.

Advantageous developments of the vane pump according to the invention are the subject matter of the dependent claims.

According to an aspect of the invention, the recess comprises in the radial direction at least two adjacent radial portions, which differ from each other in the depth of the recess with respect to the rotor end side surface. Thus, different functional or flow effective areas can be formed in the recess, in particular with regard to the sealing distance of the vane cell from the inlet and outlet openings.

According to one aspect of the invention, the radial portion of the recess located more inwardly in the radial direction of the rotor comprises a greater depth and the adjacent radial portion of the recess located more outwardly in the radial direction of the rotor comprises a lesser depth. As will be explained later, the portion with the greater depth may have the function of a pressure limiting equalization channel, and the portion with the smaller depth may have the function of a flow resistance that determines the lower threshold value of the pressure equalization.

According to an aspect of the invention, the profile of the recess or the radial portion of the recess may be constant in the circumferential direction of the rotor. Therefore, the condition of the flow effective function of the end-side concave portion is neutral with respect to the rotation angle of the rotor.

According to one aspect of the invention, the recess or the radial portion of the recess may form a groove having a rectangular, V-shaped or U-shaped profile. Such a profile in the rotationally symmetrical configuration of the recess contributes to simplifying the manufacture of the rotor, for example by machining the recess in a rotating workpiece. In the case of production by means of a sintering process, the cross-sectional profile recess ensures that the mould without undercuts can be separated from the unmachined component profile of the rotor. In particular, however, by selecting the cross-sectional profile of the recess, the flow characteristics can be influenced geometrically and thus adapted to, for example, the viscosity of the medium.

According to one aspect of the invention, the distance between the mouth of the inlet and the mouth of the outlet into the pump chamber substantially corresponds to the distance between the two vanes. Thus, the distance traveled by the enclosed space of the vane cell is minimized and the effective working distance of the vane cell is maximized. As a result, the duration of the change in the enclosed volume is minimized, so that the point in time when the space is closed and the volume is open substantially coincide with each other. In such an arrangement of the mouths of the inlet and outlet, pressure peaks can be suppressed by the additional pressure equalization effect of the recess according to the invention during the substantially simultaneous volume closure and volume opening.

According to one aspect of the invention, a hydraulic pump for generating a constant pressure for a hydraulic actuator or driver may comprise a vane pump according to the invention. As explained above, the recess effects a reduction of pressure pulsations in the blade chamber, which itself occurs in connection with a medium having a higher viscosity than water (e.g. hydraulic oil), and effects a sound damping in the closed circuit (e.g. hydraulic system).

According to one aspect of the invention, such a hydraulic pump for generating a constant pressure can have a variable volume pump geometry, wherein the distance between the rotor radius and the inner contour of the eccentric hollow cylinder or the radial lift of the pump chamber can be set by means of an actuator. In various types of variable displacement pumps, the pulsating pressure inside the vane chamber has an adverse effect on the service life, since the pressure pulsations can be transmitted directly to the actuator via the adjustable pump chamber wall in order to perform a volume adjustment of the pump. Thus, the pulsation imposes a constant vibratory load against the driving force during pump operation, causing the bearings and actuators of the adjustable pump geometry to experience vibration themselves. Because the respective kinematics are subject to stringent sealing requirements and close more rapidly with vibrations than with rigid geometries, the variable volume vane pump benefits to a certain extent from the inventive improvements for reducing pressure pulsations in the vane chambers.

According to an aspect of the present invention, such a hydraulic pump may be used as a driving source in a hydraulic power steering system for a vehicle.

Drawings

The invention will be described hereinafter by way of exemplary embodiments and with reference to the accompanying drawings, in which:

fig. 1 shows an open plan view of a variable volume vane pump according to a first embodiment of the invention;

fig. 2 shows a perspective view of a rotor with recesses according to a first embodiment of the invention;

FIG. 3 shows a perspective view of a rotor with end side recesses according to a second embodiment of the invention;

FIG. 4 shows a virtual view of a simulation of the course of a normalized pressure in a pumping chamber during the volume confinement of the vane chamber between an outlet and an inlet;

FIG. 5 shows a virtual view of a simulation resulting in a normalized flow process according to the pressure process of FIG. 6;

fig. 6 shows a graph of normalized initial pump pressure based on the rotation angles of the rotors of the vane pump according to the present invention and the conventional vane pump.

Detailed Description

The structure of the vane pump according to the present invention will be described hereinafter with reference to fig. 1 to 3.

Fig. 1 shows a view of an open pump housing 1 of a variable volume vane pump from which the pump cover has been removed. In order to be able to set the delivered volume flow independently of the rotational speed of the pump, the pump has a variable pump geometry which is adjusted by the displacement between the two housing parts.

The housing portion 1a constitutes an integral part of the pump housing 1 and houses the inlet 5, the outlet 6 and the actuator 7 with the return spring 70 therein. Furthermore, the rotor 2 is rotatably mounted in the housing part 1a, so that the rotor 2 and the housing part 1a define a fixed part with respect to the adjusting movement of the variable pump geometry. The lifting ring 1b comprising the pump chamber 10 is accommodated in a displaceable manner as an inner housing part in the outer housing part 1a together with a guide ring 13 arranged coaxially therewith, thus forming a movable part in connection with the adjusting movement of the variable pump geometry.

The lifting ring 1b forms the chamber wall of the pump chamber 10 in the form of a hollow cylinder. The inner contour 12 of the cylindrical pump chamber 10 extends eccentrically with respect to the rotor 2, wherein the magnitude of the eccentricity or the distance of the center point of the pump chamber 10 and the center point of the rotor 2 is set on the basis of the linear displacement of the lifting ring 1b with respect to the outer housing part 1 a. The adjustment movement is carried out by driving an actuator 7, which actuator 7 (not further illustrated) generates a driving force along the adjustment path and thus pretensions the return spring 70 for a reversible driving movement.

The guide rings 13 are arranged on both sides with respect to the axial end of the rotor 2 and concentrically with respect to the inner contour 12 of the pump chamber 10. The guide ring 13 is fixedly connected to the lifting ring 1b so that it always has the same eccentricity as the pump chamber 10 with respect to the rotor 2 at any position of the adjustment path. A guide ring 13 is likewise arranged on the opposite axial side of the rotor 2, which is not shown. .

The rotor 2 has a sliding groove 23, in which the radially oriented blocking vanes 3 are accommodated in a displaceably mounted manner. The radial extension of the blocking vanes 3 corresponds to the distance between the guide ring 13 and the inner contour 12 of the pump chamber 10, so that the inner ends of the blocking vanes 3 slide on the guide ring 13 and the outer ends of the blocking vanes 3 slide in the inner contour 12 of the pump chamber 10 while guiding the blocking vanes 3 on a circular path through the pump chamber 10 by means of the rotating rotor 2. Furthermore, since the guide ring 13 and the inner contour 12 extend eccentrically with respect to the rotor 2, the blocking vanes 3 also slide in the radial direction into and out of the sliding grooves 23. The blocking vane 3 can be completely retracted into the sliding groove 23 relative to the rotor radius r.

The maximum flow delivered by the pump is obtained if the lifting ring 1b together with the guide ring 13 is displaced to the maximum eccentricity with respect to the rotor 2, whereby the inner contour 12 is almost in contact with the rotor radius r of the rotor 2. In this position, the maximum volume change of the vane chamber between the blocking vanes 3 is achieved during a 180 ° rotation of the rotor in the pump chamber 10. In contrast to this, a minimum flow delivered by the pump is obtained if a position is taken along the adjustment path in which there is substantially no eccentricity anymore, i.e. the centre point of the rotor 2 is arranged concentrically with the centre point of the guide ring 13 and therefore the rotation of the vane chambers inside the pump chamber 10 does not undergo any volume change.

In the upper region of fig. 1, in each case at both axial ends of the rotor 2, a crescent-shaped depression which forms the mouth of the outlet 6 into the pump chamber 10 extends in the end side chamber wall of the pump chamber 10. Substantially symmetrical to its axial symmetry, in the lower region of fig. 1, the crescent-shaped recesses which constitute the mouths of the inlets 5 into the pump chambers 10 likewise extend at both axial ends of the rotor 2 in each case. In conjunction with the indicated counter-clockwise direction of rotation of the rotor 2, the volume of the vane chamber decreases in the upper range of rotation angles and increases in the lower range of rotation angles, whereby a displacement and feed sequence is achieved between the vane chamber and the outlet 6 or the inlet 5.

There is a distance c relative to the direction of rotation between the end of the opening contour of the crescent-shaped mouth of the outlet 6 and the end of the opening contour of the crescent-shaped mouth of the inlet 5. Within the rotational distance of the distance c, the front side chamber wall is in sliding contact with the blocking vane 3 and the end surface 22 of the rotor 2.

Furthermore, the rotor 2 has a radial elevation 21 on the circumference, which elevation 21 tapers towards the sliding groove 23 and defines a rotor radius r of the rotor 2 at the sliding groove 23. Between the radial elevations 21, the radial recesses 20 are recessed within the rotor radius r and form a clearance volume which contributes to the flow behavior and to the closing of the effective working volume in the vane chamber outside the rotor radius r.

If the rotor 2 rotates and the vane chambers between the blocking vanes 3 are guided in a rotating manner through the pump chamber 10, the volume of the vane chambers increases within the rotational angle range of the crescent-shaped mouth of the inlet 5, so that the medium or hydraulic oil being conveyed is sucked into the pump chamber 10 as long as there is a communication between the vane chambers and the inlet 5. In the range of the angle of rotation of the crescent-shaped mouth of the subsequent outlet 6, the volume of the vane chamber decreases, so that hydraulic oil is discharged or pushed out as long as there is a communication between the vane chamber and the outlet 6. In the angle of rotation of the distance c between the mouth of the outlet 6 and the mouth of the inlet 5, the volume of the vane chamber is closed off, since there is no communication with the inlet 5 or the outlet 6 during this time.

If the leading blocking vane 3 of a vane chamber passes the distance c and the trailing blocking vane 3 of this vane chamber moves towards the end of the opening contour of the crescent of the outlet 6, the circumferential slope of the respective radial elevation 21 initially reaches in the end side chamber wall of the pump chamber 10 at the edge of the end of the opening contour of the crescent of the outlet 6. At this point in time, if the set position of the pump chamber is at an end position on the adjustment path with respect to the rotor radius r, the connecting section through which the volume of the vane chamber at a position upstream of the trailing barrier vane 3, which reduces the volume, is pushed from the pump chamber 10 to the outlet 6 is greatly reduced or already substantially closed. Subsequently, the blocking vane 3 exceeds the end of the opening contour of the crescent-shaped mouth of the outlet 6 and completely closes the communication between the vane chamber and the outlet 6. Shortly thereafter or substantially simultaneously, the leading blocking vane 3 passes beyond the edge at the beginning of the opening profile of the crescent of the end side chamber wall inlet 5 of the pump chamber 10 and then the closed space of the vane chamber is opened with respect to the inlet 5. The short-term containment of the volume of the vane chamber ensures a constant barrier between the crescent-shaped mouths of the inlet 5 and outlet 6, thus eliminating the hydraulic short circuit between the inlet 5 and outlet 6.

Fig. 2 shows a recess 4 according to a first embodiment of the invention. The recess 4 extends on the end side of the rotor 2 above the radially projecting cross section of the radial elevation 21, which begins at the radial recess 20. The recess 4 is subdivided into a radially outer section 40 and a radially inner section 41, which differ from each other with regard to the different depths of the recess 4. The end side surfaces of both the inner 41 and outer 40 portions of the recess 4 are recessed with respect to the end surface 22 of the rotor 2 located further radially inward.

If the blocking vane 3 is moved towards the edge of the end of the opening profile of the crescent-shaped mouth of the outlet opening 6, in which the blocking vane is inserted or retracted into the sliding groove 23 and the upstream circumferential slope of the radial lift 21 has already passed the edge at the end of the opening profile, there is substantially no opening cross section for the transported medium or hydraulic oil to escape during the further volume reduction, still remaining at the circumference of the rotor 2. However, since the concavity of the recess 4 faces the chamber wall of the pump chamber 10, a small opening cross section remains on the end side, whereby the hydraulic oil can escape at a later stage before the leading barrier vane 3 exceeds the edge of the opening contour of the crescent-shaped mouth of the outlet 6 and finally the communication between the vane chamber and the outlet 6 is interrupted. Thus, the recess 4 in the end surface of the rotor 2 allows a delayed equalizing flow, which limits or reduces the pressure increase in the vane chamber, immediately before the volume sealing of the vane chamber takes place.

In the recess 4, the inner portion 41 with the greater depth assumes the function of providing a passage for the hydraulic oil from the clearance volume of the radial recess 20. The outer portion 40 having a smaller depth generates a prescribed flow resistance by reducing the size of the flow cross section in the radial discharge direction. The flow resistance can therefore be selected based on the depth of the outer part 40 and the geometry of the recess 4 to prevent potential leakage flows which occur for a short time through the vane chamber due to the shortest possible distance c and the pressure difference between the inlet 5 and the outlet 6.

Fig. 3 shows a recess 4 according to a second embodiment of the invention. The second embodiment differs from the first embodiment in the interior 42 of the recess 4. Unlike the rectangular or U-shaped profile of the interior 41 of the recess 4 of the first embodiment, the interior 42 of the recess 4 of the second embodiment has a V-shaped profile. Thus, the recess 4 of the second embodiment forms a flatter gradient between the inner portion 42 and the outer portion 40 and therefore a greater flow resistance. The gradient and depth of the recesses 4 according to the first or second embodiment can be selected in a suitable manner, for example on the basis of the viscosity of the specified medium or hydraulic oil to be delivered.

Fig. 4 shows the course of the pressure of the vane chamber in the pump chamber 10 as a result of a virtual simulation of the pump operation with reference to different specified regions.

In the left diagram in fig. 4, the pump geometry is simulated without the recess 4. The illustrated volumes of the vane chambers correspond to the same rotational angular position of the rotor 2, as shown in fig. 1 and 2, with respect to the crescent-shaped mouth of the opening contour, inlet 5 and outlet 6 depicted thereon. It can be seen from the simulation that there is a pressure peak through the vane chamber in the bottom left position, traveling a distance from the mouth of the inlet 5 to the mouth of the outlet 6, while the space of the vane chamber is closed. If the vane chamber is moved further in the counter-clockwise direction, it enters the range of rotation angles of the inlet 5, in which the negative pressure prevails in the vane chamber until the increase in volume ends up in a position opposite to the pressure peak region. Subsequently, due to the volume reduction, a pressure increase starts in the vane cell immediately before the volume closure in the described pressure peak.

In the right drawing of fig. 4, the simulation shows a pump geometry according to the invention with a recess 4 at the end side of the radial lift 21 of the rotor 2. As can be seen in the chamber of the perspective view of the pump chamber 10, the volume of the vane chamber fills the free space of the recesses 4 on the end side which block the vanes 3 on both sides. During the course of the rotor rotation over time, the free space filled, together with the opening profile of the crescent-shaped mouth opening the inlet 5 and the outlet 6, represents an extension of the opening cross section for equalizing the flow. As shown in this illustration, a virtual simulation of the pump geometry with the recess 4 shown on the right results in a pressure peak that is greatly reduced to a level substantially comparable to the displacement phase that has previously passed, and in which there is a complete opening to the mouth of the outlet 6.

Fig. 5 shows the distribution of the pressure equalization flow from the vane cell immediately before the volume is closed, wherein the angular position of rotation again corresponds to that of fig. 1 and 4. The size and length of the illustrated vector arrows correspond to the flow rate or volume flow per unit area of the flow cross-section.

In the left figure, which relates to the pump geometry without recess 4, the vector arrow at the centre of the view, which appears at the edge of the opening profile of the mouth of outlet 6, is much larger than the vector arrow at the upper region of the view, which represents the flow during the subsequent vane chamber cleaning phase. This high flow is caused by a small opening cross-section which remains where the radial elevations 21 overlap with the opening profile of the mouth of the outlet 6.

In contrast, the right drawing of the pump geometry with the recess 4 illustrates a larger remaining opening cross section between the vane chamber and the outlet 6 after the radial lift 21 has partly passed the opening contour of the mouth of the outlet 6. The vector arrows pointing upwards indicate that the flow rate in the critical range is still larger than in the following vane cell displacement phase. However, when comparing the left and right diagrams, it can be said that a reduction in the increase in the flow rate is achieved with the recess 4.

Fig. 6 shows a graph of the delivery pressure on the output side of the pump based on the rotation angle of the rotor 2. The dashed line represents the pressure course of the pump geometry without the recess 4 and the solid line represents the pressure course of the pump geometry according to the invention with the recess 4. The pressure course and the resulting flow rate distribution, which have been described with reference to fig. 4 and 5, propagate to the outlet 6 of the pump, thus generating fluctuations in the delivery pressure on the output side of the pump. In contrast to the delivery pressure, which is normalized to the mean value and is 1.00 < - > as shown in fig. 6, a pressure pulsation with a difference of 0.23 < - > occurs with the conventional rotor 2 every time a vane chamber passes, whereas the inventive pump geometry with the recess 4 reduces the pressure pulsation to a pressure pulsation with a difference of 0.19 < - >.

Apart from the embodiments shown and described, the vane pump used in the invention can likewise have a different pump housing 1. For example, the pump housing 1 may be volumetrically adjusted with different kinematics, where a pivoting motion between the inner profile of the pump chamber 10 and the rotor 2 is employed rather than a linear displacement as known from other types of variable displacement pumps. Further, the pump chamber 10 may have an inner contour 12 instead of the inner contour of an eccentric hollow cylinder. For example, the inner contour 12 of the pump chamber 10 can have at least one cam-shaped elevation relative to the rotor radius r.