DE102011008294B4 - pump - Google Patents

Abstract

The present invention relates to a pump unit comprising a pump housing with a cylindrical receiving space for receiving a pump and a motor housing, wherein the motor housing for receiving a motor for driving a pumping device is used and the pump has a substantially cup-shaped housing (12) having a cylindrical side wall portion and a bottom portion and which receives the pumping device with at least one pumping chamber. Through the pump chamber flows during operation of the pump to be pumped fluid. A cover defining the pump chamber is connected to the side wall portion of the housing.

Description

The present invention relates to a pump unit which comprises a pump housing with a cylindrical receiving space for receiving a pump and a motor housing as used, for example, in automotive engineering.

Pumps are needed in many areas, for example to transport fluids, to provide pressure for a hydraulic system, or to create a vacuum or vacuum. In principle, fluids can be any gaseous or liquid substances.

In many cases, it is necessary that such pumps are constructed compact, so that they can be easily integrated into the usually tight space of a device or a vehicle. In addition, due to ever-increasing cost pressure, the production costs of a pump play an essential role. However, lower production costs must not be at the expense of reliability. From the DE 2700855 A1 is known a pump whose parts are held together by a sheet metal housing. It has a cylindrical receiving space for a pump and a section for a motor. This prior art shows a design that is elaborate. From the publication DE 2844908 A1 is a pump with cup-shaped housing is known, but also shows no integrated mounting of a motor in the pump unit. From the DE 8115163 is known a rotary vane pump, the working space is enclosed in parts by a housing, but no robust solution with integration of pump and motor in a pump unit is done. It is therefore an object of the invention to provide a reliable pump which is compact and robust and which is inexpensive to manufacture.

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

The pump unit according to the invention comprises a pump housing with a cylindrical receiving space for receiving a pump and a motor housing; the pump has a substantially cup-shaped housing, which comprises a cylindrical side wall portion and a bottom portion and which receives a pumping device with at least one pumping chamber. Through the pump chamber flows during operation of the pump to be pumped fluid. A cover defining the pump chamber is connected to the side wall portion of the housing.

In other words, the pumping action of the pump generating pump means is disposed in the cup-shaped housing. The housing is closed by a lid by being connected to the side wall portion. The lid, which is particularly - but not necessarily - integrally formed, however, not only serves to seal the housing, but he also limits the pump chamber. Ie. the lid is in contact with the fluid to be delivered.

The housing and the cover may be made of metal or plastic. Preferably, the housing is made of a thin sheet metal or a metal tube.

The use of a cup-shaped housing allows a compact construction of the pump. In addition, a good shielding of the pumping device is ensured. By the double function of the lid as a pump chamber boundary and as a closure of the housing also components can be saved, which has an advantageous effect on the component costs and installation costs of the pump.

Further embodiments of the invention are given in the description, the drawings and the claims.

The sidewall portion may include integral centering aids to facilitate insertion of the pumping device and to ensure proper positioning thereof within the housing.

A simple and at the same time robust connection of the cover to the side wall portion can be realized in one embodiment of the pump, the housing has at least one flange portion which projects radially inwardly from the cylindrical side wall portion and which engages over the lid. The flange portion may for example be a circumferential ring or comprise one or more tabs, which are spaced apart, for example, in the circumferential direction and which have a ring-segment-shaped configuration.

The connection of the lid with the side wall portion is realized with a plastic cold forming compound, in particular a crimp / crimp or a thermoplastic compound.

A further component reduction is achieved when the side wall portion and the bottom portion of the housing are integrally formed. In principle, it is also possible that the side wall portion and the bottom portion are separate components, for example, by one of aforementioned compounds are interconnected.

In one embodiment of the invention, the pumping means between the lid and the bottom portion is axially fixed in the housing. In other words, the pump device is ultimately held in the region of the cylindrical side wall section by the flange section securing the cover in at least one axial direction and the bottom section.

It can be provided an elastic element which exerts on the pumping means a biasing force which presses the pumping means in an assembled state of the pump against the lid and / or the bottom portion. By a suitable embodiment of the elastic element ensures that the pumping device is reliably held in the housing. The biasing force can also be used to fix the functional components of the pumping device relative to each other so that no further components are required by which the components of the pumping device are kept in a functional bond.

According to one embodiment, the elastic element is formed on the lid and / or on the bottom portion. It is structurally simple and effective at the same time when the elastic element is formed integrally with the lid and / or the bottom section. In particular, the elastic element is formed by a formed in the lid or in the bottom portion portion with a curved or corrugated in cross-section.

Alternatively, the elastic element may be a separate spring element, in particular a plate spring. It is also possible, if necessary, to combine a separate spring element with an elastic element formed on the cover and / or on the bottom section.

Between the bottom portion and the side facing away from the lid of the pump chamber, an intermediate floor may be arranged. Thus, for example, causes the bottom portion is not directly in contact with the pump chamber. If necessary, the intermediate floor can be integrated into the floor section.

A correct assembly of the pump and in particular the pumping device can be ensured by an annular spacer which defines a distance between the bottom portion and the intermediate bottom on the one hand and the lid on the other. The spacer may be formed so as to limit the pump chamber in the circumferential direction. If necessary, the spacer can be integrated in the side wall section.

It can be provided that the bottom portion has an opening through which a drive shaft of the pumping device is guided into the interior of the housing, wherein the opening in particular receives a bearing for supporting the drive shaft. The bearing can be any type of bearing, such as a rolling bearing or a plain bearing.

The pumping device is in particular a positive displacement pump, for example a vane cell pump. In principle, however, it is also possible to use a pumping device based on a different functional principle, if necessary.

The invention thus relates to a pump unit comprising a pump section or a pump housing with a cylindrical receiving space for receiving a pump according to one of the embodiments described above and a motor section having a motor housing for receiving a motor for driving the pumping device. The engine is for example an electric motor.

The pump unit according to the invention is a compact module which comprises the actual pump and its drive. One advantage of such modules is, among other things, that they can be easily integrated into existing systems.

The pump section may have a bottom forming a partition between the motor and the pump to shield them from each other. In particular, the floor simultaneously acts as a brush holder of the engine if it is an electric motor.

The receiving space of the pump section can be dimensioned such that in the assembled state between the radial outer wall of the pump and the radial inner wall of the pump section at least partially an annular space is formed, through which during operation of the pump unit, a fluid conveyed by the pumping device flows. The annular space may communicate with at least one recess which acts as a dirt trap and is in particular annular, which extends in the axial direction of the pump section. The debris trapping function of the recess is optimized when positioned at a location where a substantially axial flow of the delivered fluid is converted to a substantially radial flow.

In principle, alternatively or additionally, a dirt trap connected to the annular space may be provided, which extends in the radial direction of the pump section, wherein the dirt trap is positioned in particular at a point at which a substantially radial flow of the conveyed fluid into an in Substantial axial flow is converted.

Hereinafter, the present invention will be explained purely by way of example with reference to advantageous embodiments with reference to the accompanying drawings. Show it:

1 an exploded view of an embodiment of the pump according to the invention,

2a and 2 B Perspective views of an embodiment of the pump according to the invention for explaining the connection between the side wall portion and the lid,

3 a cross section through an embodiment of the pump according to the invention,

4 an exploded view of an embodiment of the pump unit according to the invention and

5 a cross section through the pump unit of 4 ,

1 shows the components of a pump 10 , The pump 10 includes a housing 12 , which is based on the principle of operation of a vane pump pumping device 14 receives. The pot-shaped housing 12 includes a cylinder section 29 and a cylinder portion 29 in the axial direction unilaterally final floor 30 ,

The pumping device 14 has a rotor 16 on, for the storage of wings 18 with correspondingly shaped recesses 20 is provided. On the periphery, the pumping device 14 through a ring 22 limited. In the axial direction form a lid 24 and an intermediate floor 26 the limitation of the pumping device 14 ,

The ring 22 as well as the lid 24 and the intermediate floor 26 are the static components of the pumping device 14 , During operation of the pumping device 14 Fluid enters through an opening 28 of the lid 24 in the interior of the pumping device 14 one. Two adjacent wings 18 and a corresponding portion of a radial outside of the rotor 16 and a corresponding portion of the inner surface of the ring 22 each form a work cell or pump chamber. Due to a symmetry or central axis of the ring 22 offset rotational axis of the rotor 16 (or a non-circular cross section of the rotor 16 ) is caused by a rotational movement of the rotor 16 relative to the ring 22 causes a reduction in the volume of the pump chambers, which ultimately has an increase in the fluid pressure result. Through an opening 28 ' in the intermediate floor 26 and a corresponding opening 28 '' in the ground 30 of the housing 12 the compressed fluid is expelled again. For example, when using the pump 10 as a vacuum pump air through the opening 28 sucked and inside the pumping device 14 compressed before they pump 10 through the openings 28 ' . 28 '' leaves again.

It is understood that the fluid in principle also in the reverse direction through the pump 10 can be promoted.

From the foregoing, it can be seen that the pumping device 14 includes only a few components and therefore is inexpensive and easy to assemble. The cylinder section 29 of the housing 12 protects the components of the pumping device 14 in assembled state of the pump 10 in the circumferential direction, while the ground 30 one of the axial openings of the cylinder portion 29 closes. The other side of the cylinder section 29 is through the lid 24 closed, with the cylinder section 29 is firmly connected. The lid 24 thus fulfills a dual function: On the one hand, it limits the pump chambers in the pump direction 14 in the axial direction, on the other hand, it serves for reliable closure of the housing 12 ,

The floor 30 has a drive opening 32 on, through which a pumping device 14 driving shaft of a motor, not shown in the interior of the pump 10 can be performed. The shaft is through a warehouse 34 in one of the drive opening 32 associated cylindrical extension 32a stored.

2a shows the components of the pumping device 14 in assembled condition. To the assembly of the pump 10 To complete, one is in the axial direction on an outside 36 of the lid 24 projecting portion of the cylinder portion 29 bent so that a radially inwardly extending flange portion 38 arises, the pumping device 14 inside the case 12 assures, as in 2 B you can see. In other words, the cylinder portion 29 and the lid 24 firmly connected by a crimp or Crimpverbindung.

3 shows a partial view of a cross section through the pump 10 before making the crimped connection. It can be seen that the ground 30 a bulge 40 which has a transition area between the ground 30 and the cylinder section 29 forms. The bulge 40 represents an elastic element that provides an elastic connection between the ground 30 and the cylinder portion 29 manufactures. As a result, component tolerances can be compensated so that the components of the pumping device 14 always aligned correctly with each other. It also gets through the bulge 40 generates a biasing force, the defined clamping action in the axial direction of the components of the pumping device 14 also after preparation of the crimp connection described above. In other words, the lid 24 and the intermediate floor 26 , their correct distance through the width of the ring 22 is set, with a predefined force compressed, which are the components of the pumping device 14 holds together.

Instead of the bulge 40 For example, another geometric configuration can be selected which produces the desired elastic effect. It is also possible, alternatively or additionally, a separate elastic element in the housing 12 to position to provide the described biasing force. Such an elastic element may be for example an annular spring or a plate spring.

4 shows a pump unit 42 with a motor section 42a and a pump section 42b ,

The engine section 42a has a housing 44a on, a motor, not shown, for driving the pumping device 14 the pump 10 receives. A drive shaft 46 of the engine protrudes into a through a cylindrical pump housing 44b formed receiving space, the pump 10 receives. The pump housing 44b is after inserting the pump 10 in the receiving space and a connection of the rotor 16 the pumping device 14 with the drive shaft 46 through a closure lid 48 with a connection 50 closed to the supply or removal of fluid. The connection 50 stands with the opening 28 in fluid communication.

5 shows a cross section through a part of the pump unit 42 , It can be seen that the engine case 44a and the pump housing 44b are separate components which are interconnected by a crimp connection. The pump housing 44b includes a bottom section 52 that the engine and the pump 10 spatially separated from each other. The bottom section 52 has an annular stop 54 on, the extension 32a absorbs and thus a correct positioning of the pump 10 - In both the axial and in the radial direction - in the receiving space of the pump housing 44b ensures. The bottom section 52 can also act as a brush holder of the engine, if this is an electric motor.

Between the cylinder section 29 and the inner wall of the pump housing 44b is an annulus 55 formed through which a compressed fluid flows from the pump 10 aspirated and subsequently ejected compressed. The fluid flows through an opening 56 in the bottom section 52 from the inside of the pump housing 44b in the motor housing 44a to cool the engine there. To prevent dirt particles from the pump housing 44b in the motor housing 44a penetrate, is an annular dirt trap 58 provided in the axial direction of the pump section 42b extends. The dirt trap 58 is located in a radial outer region of the interior of the pump housing 44b and stands with the annulus 55 in connection. At least part of it through the pump 10 ejected fluid changes its direction of flow in this area. Due to the forces acting on the particles of inertia inertial forces they are in the flow direction change in the dirt trap 58 crowded and remain there. If necessary, additional filter elements may be provided to prevent the entry of contaminants into the motor housing 44a to minimize.

LIST OF REFERENCE NUMBERS

10

pump

12

casing

14

pumping device

16

rotor

18

wing

20

recess

22

ring

24

cover

26

false floor

28, 28 ', 28' '

opening

29

cylinder section

30

ground

32

drive opening

32a

extension

34

camp

36

Cover outside

38

flange

40

derecognition

42

pump unit

42a

motor section

42b

pump section

44a

motor housing

44b

pump housing

46

drive shaft

48

cap

50

connection

52

bottom section

54

attack

55

annulus

56

opening

58

dirt trap

Claims (15)

Pump unit comprising a pump housing ( 44b ) with a cylindrical receiving space for receiving a pump and a motor housing ( 44a ), wherein the motor housing ( 44a ) for receiving a motor for driving a pump device ( 14 ) and the pump is a substantially pot-shaped housing ( 12 ) has a cylindrical side wall portion ( 29 ) and a bottom section ( 30 ) and that the pumping device ( 14 ) receives at least one pumping chamber, through which a fluid to be conveyed flows during operation of the pump, wherein a cover limiting the pump chamber ( 24 ) with the side wall portion ( 29 ) of the housing ( 12 ) by a plastic cold forming compound, in particular a flared connection with the side wall portion ( 29 ) connected is. Pump unit according to claim 1, characterized in that the housing ( 12 ) at least one flange portion ( 38 ) extending from the cylindrical side wall portion (FIG. 29 ) projects radially inwards and the lid ( 24 ) overlaps. Pump unit according to at least one of the preceding claims, characterized in that the side wall section ( 29 ) and the bottom section ( 30 ) are integrally formed. Pump unit according to at least one of the preceding claims, characterized in that the pumping device ( 14 ) between the lid ( 24 ) and the bottom section ( 30 ) in the housing ( 12 ) is axially fixed. Pump unit according to at least one of the preceding claims, characterized in that an elastic element ( 40 ) is provided, which on the pumping device ( 14 ) exerts a biasing force that the pumping device ( 14 ) in the assembled state of the pump against the lid ( 24 ) and / or the bottom section ( 30 ) presses. Pump unit according to claim 5, characterized in that the elastic element ( 40 ) on the lid ( 24 ) and / or the bottom section ( 30 ) is trained. Pump unit according to claim 6, characterized in that the elastic element ( 40 ) in one piece with the lid ( 24 ) and / or the bottom section ( 30 ) is formed, wherein the elastic element in particular by a in the lid ( 24 ) or in the bottom section ( 30 ) shaped section ( 40 ) is formed with a curved or corrugated profile in cross-section. Pump unit according to claim 5, characterized in that the elastic element ( 40 ) is a separate spring element, in particular a plate spring. Pump unit according to at least one of the preceding claims, characterized in that between the bottom section ( 30 ) and the lid ( 24 ) facing away from the pump chamber an intermediate bottom ( 26 ) is arranged. Pump unit according to at least one of the preceding claims, characterized in that a distance between the bottom portion ( 30 ) or the intermediate floor ( 26 ) on the one hand and the lid ( 24 ) on the other hand by an annular spacer ( 22 ) is defined, which limits in particular the pump chamber in the circumferential direction. Pump unit according to at least one of the preceding claims, characterized in that the bottom section ( 30 ) an opening ( 32 ), by which a drive shaft ( 46 ) of the pumping device into the interior of the housing ( 12 ), wherein the opening ( 32 ) in particular a warehouse ( 34 ) for supporting the drive shaft ( 46 ). Pump unit according to at least one of the preceding claims, characterized in that the pumping device ( 14 ) is a positive displacement pump, in particular a vane pump. Pump unit according to claim 1, characterized in that the pump housing ( 44b ) a floor ( 52 ), which forms a partition wall between the engine and the pump. Pump unit according to claim 1 or 13, characterized in that the receiving space is dimensioned such that in the assembled state between the radial outer wall of the pump and the radial inner wall of the pump housing ( 44b ) at least in sections an annular space ( 55 ) is formed, by the in operation of the pump unit by the pumping device ( 14 ) conveyed fluid flows. Pump unit according to claim 14, characterized in that the annular space ( 55 ) with at least one recess acting as a dirt trap and in particular a ring-shaped recess (US Pat. 58 ) in the axial direction of the pump housing ( 44b ), wherein the recess ( 58 ) is in particular positioned at a position at which a substantially axial flow of pumped fluid is converted into a substantially radial flow.

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