WO2002014692A1

WO2002014692A1 - Vane-cell pump

Info

Publication number: WO2002014692A1
Application number: PCT/EP2001/008341
Authority: WO
Inventors: Willi Schneider
Original assignee: Joma-Hydromechanic Gmbh
Priority date: 2000-08-17
Filing date: 2001-07-19
Publication date: 2002-02-21
Also published as: DE10040711C2; DE10040711A1

Abstract

The invention relates to a vane-cell pump (10) comprising a pump rotor (22), a drive shaft (18) linked with said pump rotor (22), and a plurality of radially displaceable rotor blades (16). A central element (14) is disposed radially within the rotor (22) and fixes the rotor blades (16) radially outwards. A rotor compartment is configured in a housing (12), and the pump rotor (22), the drive shaft (18), the central element (14) and the rotor blades (16) are disposed in said compartment. During rotation of the rotor (22), outer displacement volumes (36) are produced between the rotor (22), the housing (12) and adjacent rotor blades (16). These displacement volumes are linked with an intake or a discharge in the housing (12). In order to increase the pump capacity and reduce its size, inner displacement volumes (38) are produced between the central element (14) and the rotor (22) and are also linked with the discharge or the intake of the housing (12).

Description

Vane pump

description

The invention relates to a vane pump, with a pump rotor, with a drive shaft connected to the pump rotor, with a plurality of radially displaceable rotor blades, with a central part arranged radially inside the rotor, which essentially fixes the rotor blades radially outward and with one formed in a housing Rotor chamber, in which the pump rotor, drive shaft, central part and rotor blades are arranged, whereby external displacement volumes of variable size can be formed when the rotor rotates between the rotor, housing and adjacent rotor blades, and larger external displacement volumes with an inflow and smaller external displacement volumes with an outflow are connected in the housing.

A vane pump of the type mentioned is known from the market. It is based on the principle that, if the axis of the rotor chamber does not coincide with the axis of the rotor, displacement volumes of variable size are formed between the rotor blades when the rotor is rotating. Increasing displacement volumes lead to the suction of fluid, whereas decreasing displacement volumes cause the fluid to be conveyed. The central part provided in the known vane pump is circular there and ensures that the rotor blades are essentially radially fixed between the inner wall of the housing and the outer wall of the central part. This prevents the rotor blades from moving radially inward when the pump is at a standstill, and fluid is only conveyed at a certain speed at which the rotor blades are caused the centrifugal force is pressed outwards against the inner wall of the housing.

Vane pumps of this type are used primarily to deliver lubricants in internal combustion engines of motor vehicles. Since more and more units are to be accommodated in the engine compartments of today's motor vehicles, but the available space is limited, the corresponding units, including the vane pumps used, have to be as small as possible.

It is therefore the object of the present invention to further develop a vane pump of the type mentioned at the outset such that it builds smaller with the same delivery rate or can deliver more fluid with the same size.

In a vane pump of the type mentioned at the outset, this object is achieved in that internal displacement volumes of variable size can be formed between the central part and the rotor, and increasing internal displacement volumes are connected to the inflow and decreasing internal displacement volumes are connected to the outflow in the housing.

The solution according to the invention is as simple as it is effective: According to the invention, it was recognized that the distances between the rotor and the central part also change during operation of the known vane pump. Through the invention, the spaces formed between the rotor, adjacent rotor blades and the central part are also used as displacement volumes, which are connected to the inflow or outflow in the rotor chamber. In this way, with the same size compared to the prior art, the delivery rate can be increased considerably, since in addition to the outer displacement volumes, the inner displacement volumes are available and Promoting fluid. It goes without saying that the internal displacement volumes are overall smaller than the external displacement volumes, the delivery capacity of the vane pump according to the invention is therefore not exactly doubled by the measure according to the invention. With the same delivery rate and the same diameter of the vane pump, however, the axial overall height can be reduced by approximately 30% compared to a vane pump from the prior art.

Advantageous developments of the invention are specified in the subclaims.

It is designed so that the housing can be adjusted in the radial and / or axial direction with respect to the drive shaft. The volume flow can be varied in such a vane pump. It is particularly preferred if the quantity and the pressure of the medium to be conveyed, for example lubricating oil for pressure circulation lubrication, meet the requirements and the respective condition of a unit to be lubricated, e.g. of an internal combustion engine, can be adjusted automatically. Such devices are known in the art, e.g. known from DE 195 33 686.

Another development of the vane pump according to the invention is characterized in that the housing has at least one end face outer and inner, approximately kidney-shaped flow spaces through which the outer and inner displacement volumes can be connected to the inflow and the outflow. The kidney shape results from the path of the increasing or decreasing displacement volumes.

It is particularly preferred if the inner kidney-shaped flow spaces over the outer Flow spaces are arranged mirror-inverted. This ensures, among other things, that the distances between the flow spaces are constant and that no sealing problems can arise between adjacent flow spaces.

It is furthermore particularly preferred if the inner kidney-shaped flow spaces have essentially the same angular extent as the outer flow spaces. The suction phases of the outer displacement volumes thus overlap with the delivery phases of the inner displacement volumes, and vice versa. This reduces the pressure fluctuations or fluctuations in the flow rate.

Furthermore, the rotor can be connected to the drive shaft via at least one essentially disk-shaped element. It applies that the thinner the disk-shaped element, the larger the internal displacement spaces can be designed. Ultimately, the design criterion for the disk-shaped element is the safe transmission of power from the drive shaft to the rotor.

On the one hand, there is the possibility that the disk-shaped element is axially spaced from the end faces of the rotor, such that internal displacement volumes can be formed on both sides of the disk-shaped element. As a result, a relatively large delivery capacity can be achieved, the individual displacement volumes being relatively small. This has fluidic advantages. In addition, the forces in the vane pump become more homogeneous.

In order to equalize the pressure between mutually opposite inner displacement volumes, passages can also be present in the disk-shaped element, via which corresponding inner displacement volumes can be found on both sides of the disk-shaped element are connected.

As an alternative to this, the disk-shaped element can also be arranged at an axial end of the rotor, in such a way that displacement volumes are formed only on one side of the disk-shaped element. This has among other things the advantage that, depending on the installation situation, the drive shaft does not have to be passed through the central part. The central part does not have to be ring-shaped or tubular, but can consist of a solid material.

Exemplary embodiments of the present invention are explained in detail below with reference to the accompanying drawing. The drawing shows:

Figure 1 ^'is an axial plan view of a first

Embodiment of a vane pump in a B. operating position;

Figure 2 shows the vane pump of Figure 1 in a different operating position;

Figure 3 is a partially sectioned view taken along the line III-III of Figure 1;

Figure 4 is a partially sectioned view similar to Figure 3 of a second exemplary embodiment of a vane pump;

Figure 5 is a partially sectioned view taken along the line IV-IV of Figure 2; and

Figure 6 is a partially sectioned view similar to Figure 5 of the second embodiment of a vane pump. In all the figures, a vane pump has the overall reference number 10. It comprises a tubular, circular-cylindrical housing 12 and an annular or tubular central part 14 arranged coaxially with the housing 12. A total of nine plate-like rotor blades are distributed between the central part 14 and the housing 12 16 arranged, which extend in the axial direction approximately over the length of the housing 12 (see FIG. 3) and in the radial direction from the outer wall of the central part 14 to the inner wall of the housing 12.

The vane pump 10 further comprises a drive shaft 18, the longitudinal axis 19 of which is parallel to the longitudinal axis 21 of the housing 12, but is radially offset from it, that is to say arranged eccentrically. A disc-shaped element 20 (see FIG. 3), on which a rotor 22 is molded, sits on the drive shaft 18 in a press fit. The rotor 22 is also a tubular part, the longitudinal axis of which extends parallel to the longitudinal axis of the housing 12, but coaxially with the eccentric drive shaft 18.

As can be seen in particular from FIGS. 3 and 5, the drive shaft 18 passes through the housing 12 over its entire longitudinal direction and the disk-shaped element 20 is placed on the drive shaft 18 approximately in its axial center. Correspondingly, the rotor 22 extends on both sides of the disk-shaped element 20 to the axial ends of the housing 12. In the rotor 22 there are a total of nine slot-like and radially extending openings 24 distributed over the circumference, in which the rotor blades 16 are radially displaceable, but in Are essentially fluid-tight.

It should be pointed out at this point that FIGS. 1 and 2 differ only by the angular position of the drive shaft 18 and thereby also of the rotor 22 and Differentiate wings 16.

The housing 12 is closed at its axial end faces by a cover which is transparent in FIGS. 1 and 2 for better illustration, but is not shown in FIGS. 3 and 4. The lid itself has no reference numerals in FIGS. 1 and 2. In the upper cover visible in FIGS. 1 and 2 there are kidney-shaped flow spaces which extend essentially in the circumferential direction. The radially outer and left flow space in FIGS. 1 and 2 is used as the outer suction kidney 26, the corresponding flow space on the right side as the outer pressure kidney 28, the radially inner flow space arranged on the left side as the inner pressure kidney 30 and the corresponding radially inner right one Flow space referred to as inner suction kidney 32. "Inside" and "outside" is to be understood radially.

The kidney-shaped flow spaces extend in the circumferential direction over an angular extent of approximately 135 ° in each case. The outer kidney-shaped flow spaces 26 and 28 become wider from bottom to top in FIGS. 1 and 2, whereas the inner kidney-shaped flow spaces 30 and 32 are widened mirror-inverted from top to bottom. The shape of the flow spaces and their radial position results from the path and size of the corresponding spaces formed between the vanes 16. The suction kidneys 26 and 32 are connected to an inflow (not shown) present in the housing 12, whereas the pressure kidneys 28 and 30 are connected to an outflow (not shown) also present in the housing 12.

The vane pump 10 shown in FIGS. 1 and 2 operates as follows:

By rotating the drive shaft 18 clockwise (Arrow 34 in FIGS. 1 and 2), the rotor 22 is also rotated via the disk-shaped element 20. As a result, the rotor blades 16 are also moved in the circumferential direction of the housing 12 or of the central part 14. Since the rotor 22 is arranged eccentrically with respect to the housing 12, in the course of the rotational movement between adjacent rotor blades 16, the radially outer wall of the rotor 22 and the radially inner wall of the housing 12, outer displacement volumes 36 are formed, which, as viewed in the direction of rotation, widening the gap between rotor 22 and housing 12 become larger and become smaller as the gap becomes smaller. These outer displacement volumes 26 reach the maximum size in the upper area of the vane pump 10 in FIGS. 1 and 2. Such a maximum outer displacement volume 36 is shown cross-hatched in FIG.

The increasing outer displacement volumes 36 are connected to the inflow in the housing 12 via the outer suction kidney 26 and can thus be filled with a corresponding fluid. The fluid can be gas or a liquid. If the vane pump is used as a lubricant pump for an internal combustion engine in a motor vehicle, the fluid is lubricating oil. Outer displacement volumes 36, which become smaller, are connected to the outlet in the housing 12 via the outer pressure kidney 28. The lubricant is thus conveyed from the decreasing displacement volume 36 into the outer pressure kidney 28 and from there to the outlet.

As can be seen from FIGS. 1 and 2 and also from FIGS. 3 and 5, in the course of the rotational movement 34, internal displacement volumes 38 are also formed between the rotor 22, adjacent rotor blades 16 and the central part 14. The greatest internal displacement volume is in the lowest area of the vane pump 10 in FIGS. 1 and 2 reached; it is also shown cross-hatched in FIG. Increasing inner displacement volumes 38 are also connected to the inflow in the housing 12 via the inner suction cardioid 32, so that they also fill with lubricant in the course of the rotational movement. Smaller internal displacement volumes are also connected to the drain in the housing 12 via the inner pressure kidney 33, so that they likewise convey lubricants into the drain.

In this way, lubricant is not only conveyed through the outer displacement volumes 36, but also through the inner displacement volumes 38, whereby the delivery capacity of the vane pump 10 is significantly increased with the same size. Conversely, the overall size of the vane pump 10 can be reduced in order to achieve a specific delivery rate.

In the exemplary embodiment shown in FIGS. 1, 2, 3 and 5, the disk-shaped element 20 lies approximately centrally on the drive shaft 18. Thus, internal displacement volumes 38a and 38b are formed on both sides of the disk-shaped element. In this case, corresponding flow spaces which are connected to the inflow or outflow are required on each end face of the housing 12. Possibly. The respectively opposite upper and lower inner displacement volumes 38a and 38b can be connected to one another by recesses in the disk-shaped element 20. In this case, corresponding flow spaces could also be provided only on one axial end face.

The advantage of such a central arrangement of the disc-shaped element 20 is that the forces within the vane pump 10 are distributed more evenly. Are the displacement volumes on both sides of the disc-shaped element 20 fluidically separated from one another, different fluid circuits could also be conveyed by one and the same vane pump 10.

In contrast to the exemplary embodiment shown in FIGS. 1, 2, 3 and 5, in the exemplary embodiment shown in FIGS. 4 and 6 the disc-shaped element 20 is arranged in the region of the upper axial end of the housing 12 in the figures (it should be pointed out that such elements in FIGS. 4 and 6, which are functionally equivalent to elements of FIGS. 3 and 5, have the same reference numerals and are not explained again in detail). In this way, as seen in the axial direction of the vane pump 10, there are not separate internal displacement volumes 38, but only one continuous internal displacement volume 38. In an exemplary embodiment not shown, in such a case the drive shaft 18 could also be axially guided only up to the disk-shaped element 20 such that there is no drive shaft 18 within the vane pump 10.

In a further exemplary embodiment, not shown, the extent of the eccentricity of the drive shaft 18 relative to the housing 12 can be set. The adjustment range preferably extends up to a coaxial arrangement of the drive shaft 18 to the housing 12. In the case of a coaxial drive shaft 18 to the housing 12, the displacement volumes 36 and 38 have a constant size over their movement path, so that fluid is no longer conveyed. With such an adjustability, the delivery capacity of the vane pump can be adjusted or adapted to changing external requirements. In the same direction there is an axial adjustability of the housing relative to the shaft or the rotor, which can be provided as an alternative or in addition to the radial adjustment can.

In a further embodiment, also not shown, the central part 14 is made in one piece with the housing 12. The one-piece design can e.g. be produced by an axial housing cover also provided in one piece with central part 14 and housing 12. This further simplifies the manufacture of the vane pump 10 and reduces costs. Analogously to this, the drive shaft 18, the disk-shaped element 20 and the rotor 22 could also be molded onto one another. This would also lead to a reduction in the number of separate parts and a simplification even when the vane pump was installed.

Claims

claims

1. Vane pump, with a pump rotor (22), with a drive shaft (18) connected to the pump rotor (22), with a plurality of radially displaceable rotor blades

(16), with a central part (14) arranged radially inside the rotor (22), which essentially fixes the rotor blades (16) radially outwards, and with a rotor chamber formed in a housing (12), in the pump rotor (22) , Drive shaft (18), central part (14) and rotor blades (16) are arranged, wherein when the rotor (22) rotates between the rotor (22), housing (12) and adjacent rotor blades (16), external displacement volumes (36) of variable size can be formed and increasing external displacement volumes (36) with an inflow and decreasing external displacement volumes (36) with an outflow in the housing (12), characterized in that between the central part (14) and the rotor (22) internal displacement volumes ( 38) of variable size, and increasing internal displacement volumes (38) with the inflow and decreasing internal displacement volumes (38) with the outflow i m housing (12) are connected.

2. Vane pump according to claim 1, characterized in that the housing is adjustable relative to the drive shaft in the radial and / or axial direction.

3. Vane pump according to one of claims 1 or 2, characterized in that the housing (12) on at least one end face has outer and inner approximately kidney-shaped flow spaces (26, 28, 30, 32) through which the outer and the inner Displacement volumes (36, 38) can be connected to the inflow and outflow.

4. Vane pump according to claim 3, characterized in that the inner kidney-shaped flow spaces (30, 32) are arranged mirror-inverted with respect to the outer kidney-shaped flow spaces (26, 28).

5. Vane pump according to one of claims 3 or 4, characterized in that the inner kidney-shaped flow spaces (30, 32) have essentially the same angular extent as the outer flow spaces (26, 28).

6. Vane pump according to one of the preceding claims, characterized in that the rotor (22) via at least one substantially disc-shaped element (20) is connected to the drive shaft (18).

7. Vane pump according to claim 6, characterized in that the disc-shaped element (20) is axially spaced from the end faces of the rotor (22), such that inner displacement volumes (38a, 38b) are formed on both sides of the disc-shaped element (20) can.

8. Vane pump according to claim 7, characterized in that passages are present in the disc-shaped element, via which corresponding internal displacement volumes are connected to each other on both sides of the disc-shaped element.

9. Vane pump according to claim 6, characterized in that the disc-shaped element (20) is arranged at an axial end of the rotor (22), such that internal displacement volumes (38) are formed only on one side of the disk-shaped element (20).