WO2009121470A1

WO2009121470A1 - Pump, particularly vane pump

Info

Publication number: WO2009121470A1
Application number: PCT/EP2009/001756
Authority: WO
Inventors: Johannes Maas
Original assignee: Ixetic Bad Homburg Gmbh
Priority date: 2008-04-04
Filing date: 2009-03-12
Publication date: 2009-10-08
Also published as: DE112009000553A5; EP2268899A1; EP2268899B1

Abstract

The invention relates to a pump, particularly a vane pump, having a rotor comprising radial vane slots, which are provided for guiding vanes that can be extended from the vane slots radially to the outside in the direction of a stroke contour in order to effect suction in at least one suction region, which is connected to a pump inlet, and in order to effect pressurization of a working medium in at least one pressure region, which is connected to a pressure outlet, and further having a plurality of bottom vane supply regions. The invention is characterized in that a start bottom vane extension section is arranged and designed such that during startup of the pump exactly one vane, which is moving through the start bottom vane extension section with the radial inner end thereof, is extended.

Description

Pump, in particular vane pump

The invention relates to a pump, in particular a vane pump, having a rotor having radially extending vane slots, which serve to guide wings, which are extendable radially outward from the vane slots in the direction of a stroke contour, in at least one suction region, with a Pump inlet communicates, a suction and in at least one pressure area, which is in communication with a pump outlet to cause a pressurization of a working medium, and with several under-wing supply areas.

The wings project radially inward into the underfloor supply regions, in which a medium, preferably the working medium, is pressurized in order to bring about an extension of the vanes or to keep the vanes in the extended state.

The object of the invention is the startup behavior of a pump, in particular a vane pump, with a rotor having radially extending vane slots, which serve to guide wings, which are extendable radially outward from the vane slots in the direction of a stroke contour to at least one Suction area, which communicates with a pump inlet, a suction and in at least one pressure area, which is in communication with a pump outlet, to effect a pressurization of a working medium, and to improve with several under wing supply areas.

The object is in a pump, in particular a vane pump, with a rotor having radially extending vane slots, which serve to guide wings, which are extendable radially outward from the vane slots in the direction of a stroke contour, in at least one suction region with a pump inlet, suction and in at least one pressure area, which is in communication with a pump outlet to effect pressurization of a working medium, and having a plurality of underfloor supply areas, achieved in that a Startunterflügelausfahrabschnitt is arranged and formed so that Starting the pump exactly one wing, which moves with its radially inner end by the Startunterflaugausfahrabschnitt is extended. One wing is sufficient to separate the pressure area from the suction area. Through the targeted Extending only one wing can save pressure energy when starting the pump.

A preferred embodiment of the pump is characterized in that the Startunterflügelausfahrabschnitt in the installed state of the pump, based on the Erdschwerkraft, in an upper half of the pump or the Hubkontur is arranged. In the upper half of the pump, in particular in a separation region between the suction and the pressure region, it can happen that the blades fall or retract when the pump is at a standstill due to the earth's gravity. The inventive arrangement of the Startunterflaugausfahrabschnitts a quick extension of the wings, especially in the separation area, ensured.

A further preferred exemplary embodiment of the pump is characterized in that the start lower vane discharge section is arranged radially inwardly and in the circumferential direction partially overlapping the suction region. The stroke contour runs in the suction area so that the wings can move out of their retracted state to the outside.

A further preferred embodiment of the pump is characterized in that the start lower vane discharge section extends into a separation region which is arranged in the circumferential direction between the suction region and the pressure region. The separation region is preferably arranged in a great circle of the stroke contour.

A further preferred embodiment of the pump is characterized in that the Startunterflügelausfahrabschnitt with a Unterflügeldruckabschnitt is in communication, which is disposed radially inwardly and circumferentially partially overlapping to a pressure range in which the Hubkontur runs so that the wings stroke contour in operation of the pump their extended state are moved radially inward. It displaces existing working fluid in the wing slots. The displaced working medium volume is used in accordance with an essential aspect of the invention to extend only a single wing in the take-off lower-wing outfeed section.

Another preferred embodiment of the pump is characterized in that the take-off downlift travel section together with the underfloor pressure section has a closed volume as long as the wing is in the take-off downlift travel section not yet extended. In the radial direction between the rotor and stroke contour and in the axial direction between two delivery chamber boundary surfaces, at least one delivery chamber is formed which comprises a suction region and a pressure region. Closed volume in this context means, in particular, that the take-off down-take-out section and the under-wing pressure section do not communicate with the pressure outlet of the pump as in conventional pumps. The enclosed volume prevents working fluid from escaping from the starting underfloor exhaust section or the underfloor pressure section when the pump is started.

A further preferred embodiment of the pump is characterized in that the start lower vane Ausfahrabschnitt is connected via a connecting channel with the lower vane pressure section in connection. The connecting channel is preferably designed as a connecting groove. Alternatively, the connecting channel, at least partially, be designed as a bore.

A further preferred embodiment of the pump is characterized in that the connecting channel is arranged radially inside of the radially inner wing ends in their retracted state. This ensures that the retracted wings do not dip into the connection channel. The connection channel may also be arranged in another plane such as the takeoff lower flight out section and the under wing pressure section. Thus, the connecting channel can also lie radially outside, if it is arranged, for example, on the back of the plate.

A further preferred exemplary embodiment of the pump is characterized in that the starting underfloor outlet section can be connected via a valve channel to a connection underfloor supply region which communicates with the pump outlet, which is also referred to as a pressure outlet. The valve passage may originate from the takeoff underrun outfeed section.

A further preferred embodiment of the pump is characterized in that the valve channel is spaced in the radial direction of the Startunterflügelausfahrabschnitt. Preferably, both the valve channel and the starting underfloor exit section extend in the circumferential direction. - A -

A further preferred embodiment of the pump is characterized in that the valve channel is arranged in the circumferential direction overlapping to the Startunterflügelausfahrabschnitt. Preferably, both valve channel and the Startunterflügelausfahrab- section radially inwardly and circumferentially partially overlapping to the suction region.

Another preferred embodiment of the pump is characterized in that the overlap in the circumferential direction is greater than the extension of a wing slot in the same direction. The connection via the wing slot is only released when a wing arranged in the wing slot is extended by a predetermined distance.

A further preferred embodiment of the pump is characterized in that the valve passage is connectable to the take-off lower flight out section via precisely one wing slot, which is overlapped with the valve passage and the take-off down-flight exit section. The vane in the vane slot practically constitutes a valve body. As soon as the vane is extended by a certain distance, the connection between the starting vane outfeed section and the valve port is released. Then, the starting underflough exit section is connected to the pressure outlet or pump outlet via the vane slot, the valve channel and the underfloor supply area.

A further preferred embodiment of the pump is characterized in that the valve channel emanates from the connection underfloor supply region. The valve channel is connected to the pressure outlet of the pump via the connection underfloor supply area.

Another preferred embodiment of the pump is characterized in that the valve channel is designed as a valve groove. The valve groove has substantially the shape of a circular arc.

A further preferred exemplary embodiment of the pump is characterized in that the dimensions of the valve channel are matched to the dimensions of the wings, the wing slots and the stroke contour such that, during extension of the wing in the starting underfloor ejection section via exactly one wing slot, a fluid connection between the start and Unterflügelausfahrabschnitt and the valve channel is released. Then the volumes of the take-off lower flight section and the under-flight pressure section are no longer completed, but communicate with the pressure outlet of the pump through the valve passage and the underride supply area.

A further preferred embodiment of the pump is characterized in that the fluid connection between the Startunterflügelausfahrabschnitt and the valve channel is released as soon as the wing in the region of the valve channel of the stroke contour comes close or reaches the stroke contour. Then, the take-off down-wing discharge section is supplied with working fluid, which is pressurized, through the valve port and the under-puff supply area from the pressure outlet of the pump.

Another preferred embodiment of the pump is characterized in that the connection underfloor supply region is disposed radially outward of the connection channel connecting the take-off downlift travel section to the underfloor pressure section. Preferably, the connection underfloor supply region is arranged in the radial direction partly between the connection channel and the suction region.

A further preferred embodiment of the pump is characterized in that the connection underfloor supply region and the valve channel extend over the entire suction region. Preferably, the connection underrun supply area and the valve passage extend circumferentially beyond the suction area.

A further preferred embodiment of the pump is characterized in that arranged in the circumferential direction between the lower wing sections and / or areas webs are designed slightly narrower than the wing slot width. This ensures that the wing bottoms, that is, the radially inner ends of the wings are always supplied in these areas with pressurized working fluid. Alternatively, the webs can also be made wider, if they each contain at least one notch, via which the wing bottoms are supplied with pressurized working medium.

A further preferred embodiment of the pump is characterized in that between the Startunterflügelausfahrabschnitt and one or the Unterflügeldruckabschnitt a throttle or bottleneck is formed. The throttle or bottleneck is used to increase the pressure in the underfloor pressure section. Alternatively, this can also be the throttle effect of the connection channel can be used.

A further preferred embodiment of the pump is characterized in that the pump comprises two delivery chambers each having a suction region and a pressure region. Such a pump is also referred to as a double-flow pump.

A further preferred embodiment of the pump is characterized in that the start underwing outfeed section is arranged in front of a great circle separation area in the upper pump half. The one extended wing ensures that in the separation area the pressure area is separated from the suction area to allow a pump delivery.

A further preferred exemplary embodiment of the pump is characterized in that the starting lower-wing discharge section extends in the circumferential direction over substantially one cell division. A cell division corresponds to the distance between two adjacent wings or wing slots in the circumferential direction. This ensures that when starting the pump specifically only the extension of a single wing is supported.

A further preferred embodiment of the pump is characterized in that the start lower wing extension section ends in the circumferential direction shortly after the suction region. This ensures that the separation of pressure and suction at the end of the suction area is completed.

Further advantages, features and details of the invention will become apparent from the following description in which, with reference to the drawings, various embodiments are described in detail. Show it:

Figure 1 shows a vane pump in longitudinal section;

FIG. 2 is a simplified illustration of a cross-section of a vane pump with a take-off lower run-out section and a connection under-run supply area according to an exemplary embodiment of the invention and FIG Figure 3 is a similar view as in Figure 2 according to another embodiment of the invention.

In Figure 1, a vane pump 1 is greatly simplified in longitudinal section reproduced. It has a base housing 3, which is penetrated by a drive shaft 5, which engages in a rotor 7. The rotor 7 is provided on its peripheral surface with radially extending slots in which wings are arranged displaceably. The rotor 7 is surrounded by a contoured ring 9 with a stroke contour, which is designed so that at least one, preferably two sickle-shaped delivery chambers are formed. These are passed through by the wings, wherein two pump sections are realized, each with a suction and a pressure range.

The rotor 7 and the contour ring 9 with the stroke contour are sealingly against a sealing surface of the base housing 3. On the other side of these two parts, a pressure plate 11 is provided, through which the pumped by the vane pump 1 fluid from the pressure side of the pump is passed into a pressure chamber 13, which is part of a leading from the pressure side to a consumer fluid path. For this purpose, the pressure plate 1 1 is traversed by pressure channels 15, which open on the one hand to the pressure region of the pump sections and on the other hand to the pressure chamber 13.

The opening into the pressure chamber 13 conveying openings of the pressure channels 15, in particular in conventional vane pumps, closed by a designated here as cold start plate 17 and trained sealing element, which is pressed by a pressure spring 19, for example, a plate spring with a biasing force to the pressure plate 11.

From the pressure chamber 13, the pumped by the vane pump 1 fluid, preferably oil, reaches a consumer, for example to a steering aid or to a transmission. The invention shown in the following figures can be realized with or without cold start plate.

In FIGS. 2 and 3, a vane pump 21 is shown; 71 simplified in cross section. To denote the same parts, the same reference numerals are used in Figures 2 and 3. First, the general structure of the vane cell pumps 21; 71 described. In the cross sections of Figures 2 and 3, a base housing 23 is indicated in each case, in which a drive shaft 25 is rotatable about a rotation axis 24. The drive shaft 25 drives a (not shown) rotor, which has radially extending wing slots, in which wings 26, 27, 28 are slidably received.

The wings 26 to 28 are shown in Figure 3 above in their retracted state. When extending the wings 26 to 28, based on the axis of rotation 24, move radially outwards until they come with their radially outer ends to a lifting contour 29 for abutment or strike.

The vane pumps 21 shown in FIGS. 2 and 3; 71 comprise a total of ten wings, which are evenly distributed over the circumference of the rotor. The operating direction of rotation of the vane pumps is indicated by an arrow 30. In operation, the rotors of the vane pumps 21; 71 with the associated wings 26 to 28 in a clockwise direction.

The stroke contour 29 comprises two diametrically arranged sections of a great circle 31 and two further diametrically arranged sections of a small circle 32. In their retracted state, the radially outer wing ends are spaced from the great circle 31. In its extended state, the radially outer wing tips abut the great circle 31. The circumference of the radially outer wing ends in the retracted state is indicated in Figure 3 by a dashed circle 34. In Figure 2, the stroke difference is indicated by 34, when all wings have underwing pressure.

The design of the stroke contour 29 with the great circle 31 and the small circle 32 results in two substantially crescent-shaped delivery chambers, each having a suction region 36; 38 and a printing area 37; 39 include. The suction regions 36; 38 are each via a hydraulic line 41; 42 in communication with a pump inlet 43, which in turn communicates with a tank 44 (shown only in FIG. 3), from which a working medium enters the vane pump 21; 71 is sucked. The working medium is preferably hydraulic oil.

The hydraulic line 41, 42 (shown only in Figure 3), as well as other hydraulic lines still described below, be designed as a hydraulic channel, in the Base housing 23 and a pressure plate in the base housing 23 is recessed. The pressure areas 37, 39 are connected via further hydraulic lines 45; 46 with a pump outlet 48, which is also referred to as a pressure outlet, in connection, via which the vane pump 21; 71 funded working fluid, in particular hydraulic oil, is conveyed to a consumer.

In FIGS. 2 and 3, a delivery chamber boundary surface arranged in the plane of the drawing can be seen, which can be provided on a housing part or on a pressure plate (11 in FIG. 1). Between the delivery chamber boundary surface and another (not visible) delivery chamber boundary surface of the rotor with the wings 26 to 28 is rotatably arranged. The rotor, the stroke contour 29 and the delivery chamber boundary surfaces bound together with the wings vane cells, which are also referred to as Verdrängerräume. The volume of the displacement chambers changes as the rotor rotates. Then it comes in the suction areas 36; 38 to an increase in volume, which causes suction of the working medium. At the same time there is a decrease in volume in the pressure areas 37, 39, which causes a pumping of the working medium to the pump outlet 48.

A promotion of working fluid of a working medium, in particular oil, filled vane pump can take place only when the oil inlet or pump inlet is safely separated from the oil outlet or pump outlet in the working space. In a non-rotating, parked pump fall the upper wing due to their gravity in the associated slots, so that they no longer rest with their radially outer ends of the stroke contour. The lower wings also fall due to their gravity from their slots, so that they rest with their radially outer ends of the stroke contour.

FIGS. 2 and 3 each show a two-stroke vane pump 21, 71 with two suction regions 36, 38 and two pressure regions 37, 39. In the installed position of the vane pumps, the stroke contour 29 is on the great circle 31. In this installation position is in the lower half of the oil inlet or pump inlet 43 by at least one wing 49, which rests even at a standstill of the vane pump with its radially outer end to the Hubkontur 29 , separated from the oil outlet or pump outlet 48. This ensures that a lower wing pump, which includes the suction region 36 and the pressure region 37, promotes oil. However, since the wings have slipped in, this oil passes inside the pump via the oil outlet 48 and the hydraulic line 46 and the pressure region 39 to the suction region 38 of an upper wing pump which comprises the suction region 38 and the pressure region 39. Since in a separation region 68; 108 between the suction region 38 and the pressure region 39 of the upper wing pump at pump standstill (not shown) no wing with its radially outer end abuts the Hubkontur 29, it comes in the separation region of the upper wing pump to a short circuit between oil inlet and oil outlet. As a result, the start of the vane pump is difficult or prevented.

By means of the present invention, a possibility is created in a simple manner of hydraulically extending precisely against the stroke contour 29 a vane of the upper pump half that has fallen or retracted into the associated vane slot within the first revolution. As soon as, in addition to the lower separation region, the upper separation region 68; 108 is separated by the one wing in the upper pump half, the vane pump begins to promote.

When the rotor of the vane pump begins to rotate, then the wings in the lower half of the wing in the area of decreasing contour, so in the pressure area 37, mechanically pressed into the slots. During this movement, oil under the vanes, ie radially inward, is pressed into the underfloor geometry. The displaced oil is used in accordance with one aspect of the invention to exactly one in Großkreistrennbereich 68; Press 108 into the slot sunken wing in the upper pump half of the associated slot against the stroke contour 29 to separate oil inlet and oil outlet of the upper pump half of each other and set the wing pump in motion.

The vane pump 21 shown in Figure 2 includes a main underfloor supply area 50 which is disposed in the right pump half and extends slightly above into the left pump half. The main underfloor supply portion 50 includes an underfoil pressure portion 51 disposed radially inwardly and circumferentially partially overlapping with the pressure portion 39. The underfoil pressure portion 51 communicates with a lower wing suction portion 52 that is disposed radially inward and circumferentially partially overlapping with the suction portion 36. In a connection area connecting the underfloor pressure section 51 with the lower wing suction section 52, there is a bottleneck 53 provided. The lower wing suction section 52 communicates with the pump outlet 48 via a hydraulic line 54.

In the left half of the pump, a connection underfloor supply region 67 is arranged, which is also connected to the pump outlet 48 via a hydraulic line 69. In addition, in the left pump half, there is arranged a take-off underrun supply area 60 including an underfoil pressure portion 61 arranged radially inward and circumferentially partially overlapping with the pressure area 37. The under-wing pressing portion 61 communicates with a take-off lower-flight-out portion 62 via a connecting portion 64. The take-off lower run out section 62 is disposed radially inward and circumferentially overlapping with the suction area 38.

The underrun supply region 67 is disposed radially inward and circumferentially partially overlapping with the suction region 38. At the same time, the under-wing supply portion 67 is circumferentially disposed between the under-wing pressing portion 61 and the starting lower-leaking portion 62 and radially outward of the connecting portion 64. Radially outward from the connection underfloor supply region 67, a valve channel 65 in the form of a valve groove closed at its free end emerges.

The valve channel 65 extends into a separating region 68, which is arranged between the suction region 38 and the pressure region 39. By a double arrow 70, the extent of the start underwing Ausfahrabschnitts 62 is indicated in the circumferential direction.

In the exemplary embodiments illustrated in FIGS. 2 and 3, in the region of the take-off lower run-out section 62; 102 targeted only a single wing extended. With retracted upper wings, the take-off underrun supply area 60 forms a closed volume with the underwing pressure section 61, the take-off downlift travel section 62 and the connection section 64. When the rotor of the vane pump 21 starts to rotate in the operating direction 30, all of the vanes in the underwing pressure section 61 are retracted, with oil being displaced from the underwing pressure section 61 via the connecting section 64 into the starting lower vane discharge section 62. The extent 70 of the take-off lower run-out section 62 in the circumferential direction approximately corresponds to a cell division, so that only a single wing, in FIG. 2, the wing 28, is extended in the take-off lower-wing outfeed section 62. This makes it possible that the separation process is particularly rapid, that is, at a low angle of rotation, comes about. When or before the vane 28 reaches the stroke contour 29, the radially inner lower edge of the vane 28 releases a connection between the starting vane outlet section 62 and the valve channel 65 via the associated rotor slot. Thus, the vane 28 together with the associated vane slot performs a valve function.

During normal operation of the vane pump 21, a portion of the working medium is conducted via the released connection of the rotor slot to the valve channel 65 and the connection bottom supply area 67 in order to extend all wings in the suction area 38. In normal operation, the start underfloor supply area 60 is connected to the pump outlet 48 via the connection underfloor supply area 67 and the valve channel 65 as well as the hydraulic line 69.

The connecting portion 64 which connects the underfoil pressure portion 61 with the take-off underfinger extension portion 62 may, for example, be implemented as a further groove on the rotor side of the associated pressure plate, as a bore or channel within the pressure plate or housing, or as a groove on the back of the pressure plate.

The connection portion 64 between the underfoil pressure portion 61 and the takeoff underfoil outfeed portion 62 may be configured as a bottleneck, so that there is higher pressure in operation in the underfoil pressure portion 61 than in the takeoff downflight discharge portion 62. This avoids lifting the wings under operating pressure.

The exemplary embodiments illustrated in FIGS. 2 and 3 can also be used for single-stroke pumps with a delivery chamber, that is to say with only one suction region and only one pressure region.

The vane pump 21 shown in Figure 2 allows the separation of the working space of the upper vane pump in the separation area 68 with a rotation of the pump rotor by less than a quarter turn. Optionally, with an optimum angular position of the rotor, a rotation around a cell division may be sufficient. At the beginning of the rotational movement of the rotor, the wings in the lower pump half in the region of the decreasing contour, ie in the pressure range 37, mechanically retracted into the rotor slots. In the process, the working medium present in the slots, in particular oil, is displaced into the underfoil pressure section 61. The displaced oil volume is used according to an essential aspect of the invention to extend the vane 28, which is viewed in the direction of rotation 30 in front of the great circle separation region 68 of the upper wing pump, from the associated rotor slot.

In Figure 2, the wing 28 is shown in its extended condition, in which the pressure area 39 is separated from the suction area 38 by the wing 28 in the separation area 68. As a result, a short circuit in the upper pump half between the suction region 38 and the pressure region 39 is prevented and the delivery of the pump 21 is made possible.

Regardless of the position of the rotor displace upon rotation of the rotor to a cell division, the incoming wings in the pressure region 37 of the lower wing pump at least or just as much oil as a wing in the Startunterflügelausfahr- section 62 needed for extension. According to another aspect of the invention, the underfoil pressing portion 61 communicates with the take-off lower-flight-out portion 62 via the connecting portion or connecting portion 64. Thus, the oil displaced in the underfoil pressure section 61 by the retracting vane passes into the rotor slot of the vane 28, which is located in the region of the takeoff lower vane exit section 62. As a result, the wing 28 is extended in this rotor slot.

The region or the angular extent 70 of the start underfoil extension section 62 extends over approximately one cell division and ends shortly after the end of the suction region 38 of the upper wing pump. This ensures that there is always only a single wing in the area of the lower tail discharge section 62 and that the separation of the pressure and suction areas of the upper wing pump at the end of the suction area 38 is completed.

When extending the wing 28, which is located in the area of the Startunterflügelausfahrabschnitts 62, creates a connection to the radially further outward valve channel 65 which is connected directly to the connection underfloor supply area 67 above the rotor slot. In normal operation of the pump, in which all wings 26 to 28 on the stroke contour 29 on The underfoil pressure section 61 is in communication with the valve channel 65 and the underrun supply area 67 via the connection channel 64 and the start wing outlet section 62 as well as the rotor slot of the wing 28. The oil delivered by the underfloor pump in the lower half of the wing thus reaches all the wings in the suction area 38 of the upper wing pump. Similarly, the upper underfloor pump supplies all wings in the suction region 36 of the lower wing pump.

The connection underfloor supply region 67 and the valve channel 65 extend over the entire suction region 38 of the upper wing pump. The lower wing suction section 52 extends over the suction area 36 of the lower wing pump. The underfoil pressure portion 51 extends over the pressure area 39 of the upper wing pump.

Depending on the rotor position, there may be a difference between the conveyance of the underfloor pumps and the oil requirement of all extending blades of the wing pumps. This differential flow is compensated via the hydraulic lines or hydraulic channels or connecting channels 69 and 54, which are connected to the pump inlet 48.

Thus, the wings in the pressure areas 37, 39 of the wing pumps safely abut the Hubkontur 29, the pressure in the Unterflügeldruckabschnitten 51, 61 are accumulated. In the underfloor supply region 50 this is made possible by the constriction or restriction 53, which comprises a cross-sectional constriction. The increase in pressure in the starting underfloor supply region 60 can be realized by a throttling action of the connecting duct 64 or by an additional throttling point in the connecting duct 64.

The underrun supply area 67 and the lower air intake portion 52 in the suction areas 38, 36 of the wing pumps are connected to the pump outlet 48 via the hydraulic lines 69 and 54. In the two suction regions 38, 36, the wings are therefore pressed only with the non-accumulated pump pressure to the stroke contour 29.

The webs, that is, in the circumferential direction between the lower wing portion 67 and the lower wing portions 61, 62 and between the Unterflügelabschnitten 61, 62 and the Unterflügelabschnitten 51, 52 remaining material thicknesses should be performed substantially not smaller than the slot widths in the rotor, so over the wing slot no unexpected desired short circuit between the lower wing portions 61, 62 and the lower wing portion 67 is generated.

The connection channel or connection region 64 can be embodied as a groove on the rotor side of the plate visible in FIG. 2, as a bore or channel in the plate or as a groove on the rear side of the plate. When designed as a groove on the back of the plate, this channel must be covered either by housing components or by an additional component.

For pumps using a cold start plate, as indicated at 17 in Figure 1, this plate can be used as a channel cover. The cold start plate may then contain openings for the hydraulic lines or hydraulic channels or pressure channels 69, 54. According to a further aspect, the cold start behavior of the vane pump 21 is optimized by the present invention. As a result, throttling of the entire delivery flow of the vane pump 21 through the cold start plate can be dispensed with. Therefore, the vane pump according to the invention has a lower power consumption than pumps with a cold start plate.

Another advantage of the invention is that the wing in the region of the Startunterflügelausfahr- section 62 with parked vane pump initially only to the inner edge of the valve channel 65 occurs. From then on, the volume of oil is trapped in the take-off downlift section 62, in the connecting duct 64 and in the underfoil pressure section 61, so that further collapse of the vanes due to gravity is initially hindered. If the vane pump is restarted a short time later, that is, before the vane has completely collapsed, for example, on vehicles with start / stop function, then the promotion of the vane pump starts even at lower speeds.

According to a further aspect of the invention, all of the vanes of the lower underfloor pump initially convey their oil into the starting underflough discharge section 62 during the starting process. The effective area of the vanes between the rotor and the lifting contour 29 is referred to as the underfloor pump. As an underfloor pump, the effective range of the wing undersides, that is, the radially inner wing ends, referred to. According to a further aspect of the invention, the lower-mounted underfoot pump of the vane pump 21 supplies the wings in the suction region 38 of the overhead wing pump. Similarly, the overhead under wing pump supplies the wings in the suction region 36 of the underlying underfloor pump. By the invention, both the cold start and the warm start behavior of the vane pump 21 can be improved.

The vane pump 71 shown in FIG. 3 is similar to the vane pump 21 shown in FIG. 2. The vane pump 71 includes a main underfloor supply section 80 which is disposed in the right pump half and extends slightly up into the left pump half. The main undersupply area 80 includes an underfoil pressure portion 81 disposed radially inward and circumferentially partially overlapping with the pressure area 39. The underfoil pressure portion 81 communicates with a lower wing suction portion 82 which is disposed radially inward and circumferentially partially overlapping with the suction portion 36. In a connection portion connecting the underfloor pressure portion 81 to the lower wing suction portion 82, a constriction 83 is provided. The lower wing suction section 82 communicates with the pump outlet 48 via a hydraulic line 84.

Arranged in the left pump half is a connection underfloor supply region 90, which is also connected to the pump outlet 48 via a hydraulic line 94. Moreover, in the left pump half, there is disposed a take-off underrun supply area 100 including an underfoil pressure section 101 disposed radially inward and circumferentially partially overlapping with the pressure area 37. The underfloor pressing portion 101 communicates with a take-off lower-flight-out portion 102 via a connecting portion or connecting passage 103. The take-off lower run out section 102 is disposed radially inwardly and circumferentially overlapping with the suction area 38.

The underrun supply area 90 is also disposed radially inwardly and circumferentially partially overlapping the suction area 38. At the same time, the underrun supply area 90 is arranged circumferentially between the lower wing pressure portion 101 and the lower start-up run-off portion 102 and radially outward of the connecting portion 103. Radially outward from the connection underfloor supply region 90, a valve channel 105 in the form of a valve groove closed at its free end emerges. The valve channel 105 extends into a separation area 108 which is arranged between the suction area 38 and the pressure area 39. By a double arrow 111, the extension of the start underwing Ausfahrabschnitts 102 is indicated in the circumferential direction. By a double arrow 112, the distance between the free end of the valve channel 105 and the Startunterflügelausfahrabschnitt 102 and the pressure region 39 is designated in the circumferential direction. By further arrows 113, 1 14, it is indicated how far the valve channel 105 and the start lower vane outlet section 102 extend in the circumferential direction beyond the suction region 38 into the separating region 108.

In the exemplary embodiment illustrated in FIG. 3, only a single wing is intentionally extended in the great-circle separation region. When the upper wings are retracted, the take-off wing supply area 100 forms a closed volume with the underwing pressure section 101, the take-off under-run extending section 102 and the connecting section 103. When the rotor of the vane pump 71 starts to rotate in the operating direction 30, all of the vanes in the underfloor pressure section 101 are retracted, with oil being displaced from the underfloor pressure section 101 via the connection section 103 into the takeoff lower flight out section 102.

The extent 111 of the take-off underrun out section 102 in the circumferential direction approximately corresponds to a cell division so that initially only a single vane, in FIG. 3, of the vane 28 is extended in the takeoff vane outfeed section 102. This makes it possible that the separation process is particularly rapid, that is, at a low angle of rotation, comes about. When or before the vane 28 reaches the stroke contour 29, then the radially inner lower edge of the vane 28 releases a connection between the Startunterflügelausfahrabschnitt 102 and the valve channel 105 via the associated rotor slot. Thus, the vane 28 together with the associated vane slot performs a valve function.

During normal operation of the vane pump 71, a portion of the working medium is passed via the released connection to the valve channel 105 and the under wing supply area 90 in order to extend all wings in the suction area 38. In normal operation, the start-up wing supply region 100 is connected to the pump outlet 48 via the connection underfloor supply region 90 and the valve channel 105 as well as the hydraulic line 94. The connection portion 103 connecting the underfloor pressure portion 101 to the start underfloor discharge portion 102 may be performed, for example, as another groove on the running side of the associated housing plate, as a bore, or as a channel within the housing plate.

In FIG. 3, in contrast to FIG. 2, the wings in the upper pump half are shown in the retracted state.

LIST OF REFERENCES

Claims

claims

1. pump, in particular vane pump, with a rotor (7) having radially extending vane slots, which serve to guide wings (26-28,49), which are extendable from the vane slots radially outward in the direction of a stroke contour (29) for pressurizing in at least one suction region (36, 38) in communication with a pump inlet (43) and pressurizing in at least one pressure region (37, 39) associated with a pump outlet (48) Working medium and with a plurality of underfloor supply areas, characterized in that a start underfill supply area (60; 100) is arranged and designed so that when starting the pump exactly one wing (28), with its radially inner end by the start - Wing Ausfahrabschnitt (62, 102) moves, is extended.

2. Pump according to claim 1, characterized in that the starting underfloor extending portion (62; 102) in the installed state of the pump (21; 71), based on the Erdschwerkraft, in an upper half of the pump (21; 71) or the Hubkontur (29) is arranged.

3. Pump according to one of the preceding claims, characterized in that the Startunterflügelausfahrabschnitt (62; 102) is arranged radially inwardly and in the circumferential direction partially overlapping to the suction region (38).

A pump as claimed in any one of the preceding claims, characterized in that the start lower vane exhaust section (62; 102) extends into a separation region (68; 108) disposed circumferentially between the suction region (38) and the pressure region (39).

A pump as claimed in any one of the preceding claims, characterized in that said take-off downlift travel portion (62; 102) communicates with an underfoil pressure section (61; 101) disposed radially inwardly and circumferentially partially overlapping with a pressure region (37) which the stroke contour (29) extends so that the wings are moved hubkonturbedingt from its extended state radially inward during operation of the pump.

6. A pump according to claim 5, characterized in that said take-off down-wing extension portion (62; 102) has a closed volume together with said under-wing pressure portion (61; 101) as long as said wing in said take-off down-hill discharge portion (62; 102) has not yet been extended.

7. A pump according to claim 6, characterized in that the starting underfloor extending portion (62; 102) communicates with the underfloor pressure portion (61; 101) via a connecting passage (64; 103).

8. Pump according to claim 7, characterized in that the connecting channel

(64; 103) is arranged radially inwardly of the radially inner wing ends in their retracted state.

9. Pump according to one of the preceding claims, characterized in that the Startunterflügelausfahrabschnitt (62; 102) via a valve channel (65; 105) with a connection Unterflügelversorgungsbereich (67; 90) is connectable to the pump outlet (48) in conjunction stands.

A pump as claimed in claim 9, characterized in that the valve channel (65; 105) is radially spaced from the start lower vane exhaust section (62; 102).

11. A pump according to claim 9 or 10, characterized in that the valve channel (65; 105) is arranged circumferentially overlapping the Startunterflügelausfahrabschnitt (62; 102).

12. A pump according to claim 11, characterized in that the overlap in the circumferential direction is greater than the extension of a wing slot in the same direction.

A pump as claimed in any one of claims 9 to 12, characterized in that the valve passage (65; 105) is arranged over exactly one vane slot overlapping the valve passage (65; 105) and the takeoff lower flight exhaust section (62; 102) Take-off underfoot Ausfahrabschnitt (62, 102) is connectable.

14. A pump according to any one of claims 9 to 13, characterized in that the valve channel (65; 105) extends from the connection underfloor supply region (67; 90).

15. Pump according to one of claims 9 to 14, characterized in that the valve channel (65; 105) is designed as a valve groove.

16. Pump according to one of claims 9 to 15, characterized in that the dimensions of the valve channel (65; 105) are so matched to the dimensions of the wings (26-28,49), the wing slots and the stroke contour (29) that upon deployment of the wing (28) in the take-off downlift travel section (62; 102), fluid communication between the takeoff downlift travel section (62; 102) and the valve port (65; 105) is released via exactly one wing slot.

17. A pump according to claim 16, characterized in that the fluid connection between the Startunterflügelausfahrabschnitt (62; 102) and the valve channel (65; 105) is released as soon as the wing in the region of the valve channel (65; 105) of the stroke contour (29) close comes or reaches the stroke contour (29).

18. A pump according to any one of claims 9 to 17, characterized in that the connection underfloor supply portion (67; 90) is disposed radially outward of the connection channel (64; 103) which connects the take-off downlift extension portion (62; 102) with the underfloor pressure portion (61; 101) connects.

19. Pump according to one of claims 9 to 18, characterized in that the connection underfloor supply region (67; 90) and the valve channel (65; 105) extend over the entire suction region (38).

20. Pump according to one of claims 9 to 19, characterized in that in the circumferential direction between the lower wing sections (61,62; 101, 102) and / or areas (67; 90) arranged webs are designed slightly narrower than the wing slot width ,

21. Pump according to one of the preceding claims, characterized in that between the Startunterflügelausfahrabschnitt (62; 102) and one or the lower wing pressure portion (61; 101) is formed a throttle or bottleneck.

22. Pump according to one of the preceding claims, characterized in that the pump comprises two delivery chambers each having a suction region (36,38) and a pressure region (37,39).

23. Pump according to one of the preceding claims, characterized in that the Startunterflügelausfahrabschnitt (62; 102) in front of a great circle separation region (68; 108) is arranged in the upper pump half.

24. Pump according to one of the preceding claims, characterized in that the Startunterflügelausfahrabschnitt (62; 102) extends in the circumferential direction over substantially a cell division.

25. Pump according to one of the preceding claims, characterized in that the Startunterflügelausfahrabschnitt (62; 102) ends in the circumferential direction shortly after the suction region (38).