EP2948262A1

EP2948262A1 - Method for producing a vane for a rotary vane pump, vane for a rotary vane pump and rotary vane pump

Info

Publication number: EP2948262A1
Application number: EP14705702.0A
Authority: EP
Inventors: Arno Steiner; Alessandro DE NICOLÒ; Philipp NEUNHÄUSERER; Thomas OBERLEITER
Original assignee: GKN Sinter Metals Engineering GmbH
Current assignee: GKN Powder Metallurgy Engineering GmbH
Priority date: 2013-01-25
Filing date: 2014-01-24
Publication date: 2015-12-02
Anticipated expiration: 2034-01-24
Also published as: EP2948262B1; US20150352638A1; CN105102161B; DE102013001246A1; CN105102161A; US9855604B2; WO2014114461A1; BR112015017659A2; JP6367235B2; JP2016511327A

Abstract

The invention relates to a method for producing a net-shape vane for a rotary vane pump, which vane is preferably open-pored and consists of a metal sinter material. The vane has at least one first front face and one second front face which is preferably oriented parallel to the first front face, and a first lateral surface and second lateral surface that is oriented parallel to the first lateral surface. Furthermore, the vane comprises a first contour surface and a second contour surface. The method for producing the vane comprises at least the following steps: pressing (20) a powder mixture to a green body by means of a powder press, sintering (21) the green body inside a sintering furnace to a sintering element having an austenitic structure, quenching the sintering element inside the sintering furnace to a temperature below the martensitic start temperature for hardening (22), tempering (23) the sintering element preferably inside the sintering furnace, removing (24) the sintering element as net-shape vane, preferably as removal from the sintering furnace. After removing the sintering element, deburring (25) can optionally be made. The invention further relates to a vane and a rotary vane pump.

Description

Method for producing a wing for a vane pump, wings for a vane pump and vane pump

The invention relates to a method for producing a wing for a

Vane pump. Furthermore, a wing for a vane pump

proposed. Further, a vane pump is proposed.

US 2009/0114046 A1 describes a vane pump with an iron-based sintered rotor and blades made of tool steel. Wings made of SKH 51 tool steel are used as material for the blades of the vane pump.

WO 2006/123502 A1 describes a method for producing a blade from a sintered material. The wings include functionally essential radii and contours that are applied by post-processing.

The invention is based on the object to simplify the production of a vane pump.

The object is achieved with a method for producing a metallic sintered material net-shape wing for a vane pump with the features of claim 1 as well as with a wing for a vane pump according to the features of claim 10, and further with a

Vane pump solved according to the features of claim 15. Further advantageous embodiments and developments will become apparent from the following description. One or more features of the claims, the description, as well as the figures may be provided with one or more features thereof

Embodiments of the invention are linked. In particular, one or more features of the independent claims may be replaced by a plurality of other features of the description and / or figures. The

The proposed claims are to be construed as a draft only, without, however, limiting the scope of the subject matter.

A method is proposed for producing a net shape wing made of a metallic sintered material for a vane pump. The method is preferably a method for producing an open-pored net-shape wing. The wing has in this case at least a first end face and a second end face and a first side face and a parallel to this oriented second side surface up. Preferably, the second end face is parallel to the first

Face oriented. Furthermore, the wing has a first contour surface and a second contour surface. The method of manufacturing the wing comprises at least the following steps:

Pressing a powder mixture into a green compact by means of a powder press,

■ sintering of the green body within a sintering furnace to a sintered part with

austenitic structure,

■ Quenching the sintered part within the sintering furnace to a temperature

below a martensite start temperature of the sintered body for hardening the sintered body,

^■ tempering of the sintered part,

^■ Removal of the sintered part as a net-shape wing.

The term metallic sintered material refers to a material having a predominantly metallic bonding component which has been sintered. In this case, the metallic sintered material may in particular have, for example, a sintered bronze, a sintered iron or any sintered steel. However, the term metallic sintered material does not exclude that other constituents, such as ceramics, are also at least partially present in the metallic sintered material.

The term of the wing refers to a wing, in particular for a

Vane pump, usable plate. However, the term platelet does not exclude that the shape of the blade deviates from a flat, planar shape.

In this case, the wing formed as a platelet preferably has one of one

Parallelepiped with six faces at least derived form. In this case, it is possible, for example, to deviate from the shape of a parallelepiped in that two opposing surfaces of the parallelepiped are not oriented parallel to one another but enclose an angle. It can also be provided that one or more surfaces of the wing are not formed as a plane.

Preferably, both the first side surface and the side surface oriented parallel thereto are designed as flat surfaces. This results in the advantage that the wing can be inserted into a slot-shaped guide with correspondingly suitable dimensions, and then stored the wing in the slot-shaped guide is, but this is only in one or at most in two dimensions of the room is movable.

In a specific embodiment, not only the side surfaces are oriented parallel to each other, but also the first end face is arranged to the second end face in a parallel orientation.

Preferably, both the first end face and the second end face are formed as flat surfaces. A design of the first and the second end face as flat surfaces has the advantage that a dimensioning of the vane pump can be made such that the entire first end face and the entire second

End face on mutually parallel inner surfaces of a vane pump are oriented at least almost fitting, so that a perpendicular to the end face, along a so-called stimulus movement avoided or at least largely avoided.

In addition to the end faces and the side surfaces, a first contour surface and a second contour surface of the wing should also be included. The first contour surface and the second contour surface are characterized in particular in that the contour surface, for example for use of the wing in a vane pump, can be designed such that the contour surface can be optimized for passing on an inner side of a wall of the vane cell pump. Since the wing is typically guided past an inner wall of the vane pump by means of a rotational movement of a rotor of the vane pump, and the inner wall from the perspective of the wing represents an inwardly curved surface, in particular a contoured surface outwardly curved can be provided.

The contour surface can in this case be designed such that two opposite edges of the contour surface are curved. In a preferred embodiment of

Contour surface can be provided, for example, that one or both contour surfaces have a configuration of a curved rectangle.

It may be provided, for example, that the first contour surface and the second contour surface have the same surface area and both contour surfaces have the same curvature, wherein the shortest edges of the wing are curved edges. Furthermore, it can be provided that the first contour surface and the second

Contour surface are oriented parallel to each other. This results in an embodiment in which the first contour surface of the wing is curved outward and the second contour surface of the wing is curved inward or vice versa.

It may also be possible that the first contour surface is oriented in plane mirroring to the second contour surface. In this case, the first contour surface is preferably mirrored on a plane whose normal vector is oriented parallel to each of the two side surfaces as well as to each of the two end surfaces.

The preferred embodiments of the embodiments resulting from the above

Described outlined, is an embodiment of the wing as a body, which has starting from a cuboid shape, the two contour surfaces each curved with the same radius of curvature either outwardly or curved inward, with an outwardly oriented curvature of both contour surfaces is the preferred embodiment.

For example, it may be possible that the first contour surface and / or the second contour surface is adapted to an inner transformation, for example a vane pump, and that the first contour surface is oriented in area mirroring to the second contour surface. Such a design of a wing has the advantage that, due to the high symmetry of the wing in an insertion of the wing in guides provided for this purpose in a rotor of a vane pump errors in the orientation of the wing can be avoided to the inner wall of the vane pump.

It can also be provided that the first contour surface is adapted to an internal transformation, for example a vane pump, while the second contour surface has any, for example, in general a planar configuration. In a special embodiment, the wing one of a as a cuboid

trained parallelepiped derived embodiment. In this special

Embodiment, the wing 12 edges, with three different edge lengths are each four times. The cuboid hereby has edge lengths of axbxc, where a is the shortest edge with an edge length between 1 mm and 2 mm, c the longest edge with an edge length between 25 mm and 30 mm and b the medium-length edge with an edge length between 7 and 13 mm , The wing is formed in this particular embodiment in that the first contour surface and the second contour surface are bowed outwards by the shortest edge, a, is correspondingly curved and the curvature for each of the shortest edges a is identical and directed outwards, that is, away from the body, so that when viewed on the body, the curvature represents as a concave curvature.

The term net-shape refers to a perturbing design of the wing, that after removal of the wing from the furnace, in which the last

Heat treatment was made, no machining of the wing to form the tolerances of the wing is more necessary. With the concept of

Tolerances are here in particular the functionally essential Maß- and

Designated form tolerances. On the other hand, the term net-shape should not exclude, in particular, that a deburring of the blade takes place after the removal of the sintered part, in particular also in order to carry out the removal of protruding ridges which

for example, may have arisen during the pressing.

In a preferred embodiment of the method takes place after quenching of

Sintered parts within the sintering furnace, the annealing of the sintered part also within the sintering furnace. The removal of the sintered part as a net-shaped wing is also carried out in this preferred embodiment after the annealing of the sintered part

Sintering furnace, which may still be waiting for a cooling of the sintered part.

The term powder mixture includes, for example, a mixture of elemental powders or a mixture of compound powders, also denoted as alloy powders, or a mixture of elemental and / or compound powders.

The term green compact designates in the sequence of the method for the production of the wing that intermediate product which is produced by pressing, but which has not yet undergone a targeted heat treatment and, in particular, has not yet been fed into the process of sintering.

It can further be provided that the sintering of the green body within a

Sinter furnace is carried out to a sintered part with austenitic structure at a constant during the entire process step of the sintering temperature, which is then the sintering temperature. Furthermore, it can also be provided that the sintering at different temperatures, for example, in a sequential discrete sequence of sintering temperatures or in a continuous temperature profile or even a combination of a discrete and / or continuous temperature course takes place. However, a sequence of several periods of sintering of the sintered part may also be provided, which is interrupted by other periods at lower temperatures which are not yet sufficient for sintering of the sintered part.

The sintering of the green compact within the sintering furnace into a austenitic sintered compact may be accomplished, for example, by placing a temperature in a stationary phase diagram in an austenitic region immediately prior to quenching the sintered sintered sinter within the sintering furnace at that elemental composition of the elemental composition of the powder mixture which was used for the production of the compact.

In particular, it may be provided that this temperature reached immediately before the quenching of the sintered part and / or one or more within the same austenitic region in the stationary phase diagram in the

Element composition, which corresponds to the elemental composition of the powder mixture, is held for a sufficiently long time to achieve a predominantly austenitic structure of the incorporated as a green compact in the sintering furnace sintered part. Achieving a predominantly austenitic structure refers to setting of an austenitic structure in at least 50% of the volume of the sintered part.

For example, it can preferably be provided that at least 90% of the volume of the sintered part has an austenitic structure immediately before quenching of the sintered part.

In a particularly advantageous embodiment of the method can be provided, for example, that immediately before the quenching of the part almost 100% of the volume of the sintered part have an austenitic structure. In such an embodiment of the wing, in which almost 100% of the part to be sintered have an austenitic structure, almost no retained austenite is present after quenching of the sintered part. The advantage of not having a retained austenite is that there are no variations in tolerance, as a result of which an embodiment of the wing as a net-shape wing can be achieved in a particularly simple manner without any further need for reworking.

However, it may also be provided in another embodiment of the method, that a removal of the wing takes place as a net-shape wing and the tempering of the Wing without further targeted heat treatment takes place. Instead, depending on the material used, it may already be sufficient to start the wing already at ambient temperature. This may for example be the case with wings with a high proportion of light metal or light alloys.

In another embodiment of the method, the pressing of the wing takes place by the first contour surface is formed by means of at least one lower punch of the powder press and the second contour surface by means of at least one upper punch of the powder press under pressure, and the first end face, the second end face, the first side face and the second side surface are formed by at least one die of the powder press.

In an embodiment of the wing, in which the first contour surface and / or the second contour surface is that surface which is bounded by the shortest and the longest edge of the wing, this leads to a pertinent orientation of the wing that the pressure exerted by the stamp acting on the contour surfaces and arise here due to play between the upper punch and the lower punch and the dies burrs on the edges. These burrs can be removed after sintering the blade by another deburring step. Advantage of such deburring is in particular a rounding of the edges.

In a further embodiment of the method, it is provided that the pressing of the blade takes place by forming at least the first contour surface and the second contour surface by means of a die of the powder press. In this embodiment of the method, it is further provided that one or more of the first side surface, the second side surface, the first end surface and the second end surface are formed under pressure by means of a lower punch and an upper punch of the powder press. In one embodiment of the net-shape wing, in which the first contour surface and / or the second contour surface is that surface which are bounded by the shortest and the longest edge of the wing, this leads to a pertinent orientation of the wing, that of the Stamp exerted pressure primarily acting on the faces. A design of the contour surfaces takes place here by the matrices. This makes it possible that an almost arbitrarily complex design of one or both contour surfaces can be provided. Furthermore, due to the then not present game deburring is not mandatory. Furthermore, an embodiment of the method is provided in the context of which sintering takes place within a temperature range from 1050 ° C. to 1300 ° C. It can be provided that during the entire period of sintering, a stationary temperature within the temperature range of 1050 ° C to 1300 ° C is present. Furthermore, it can be provided that during the entire duration of sintering, a temperature profile is present, which takes place within the temperature price of 1050 ° C to 1300 ° C. Likewise, however, it may be provided that only

in sections during the period of sintering a stationary temperature and / or a temperature profile is present, which is between 1050 ° C and 1300 ° C, and that before and / or after and / or during sintering at least partially lower and / or higher temperatures be achieved. In a targeted change in temperature, this can be adjusted in a continuous or discrete manner.

In a preferred embodiment of the method, the sintering takes place within a temperature range of 1100 ° C to 1150 ° C. A sintering in this temperature range can be provided in particular for such alloys, in which Mo as

Alloying element with the highest or second highest concentration after Fe and C, if the concentration is considered as a proportion in wt .-%.

In another preferred embodiment of the method, the sintering takes place within a temperature range of 1250 ° C to 1300 ° C. A sintering in this

Temperature range can be provided in particular for those alloys in which Cr is present as alloying element with the highest or second highest concentration according to Fe and C, if the concentration is considered as a proportion in wt .-%.

In a further embodiment of the method can be provided that the

Quenching to a temperature within a temperature range of 100 ° C to 300 ° C takes place.

In a preferred embodiment of the method it is provided that the

Quenching takes place by means of a direct Luftanblasung. Advantage of quenching by means of a direct Luftanblasung is that a particularly simple embodiment of a quenching can take place. In particular, another advantage of a

Quenching by air blowing so that quenching can be performed inside the sintering furnace. Quenching the sintered part to a temperature below a

Martensite start temperature of the sintered part takes place here to harden the sintered part. The martensite start temperature for many of the described powder mixtures is approximately in a range between 300 ° C and 400 ° C.

Preferably, quenching should occur at a cooling rate within a range of 0.85 ° C / second and 5.0 ° C / second. In a particularly preferred embodiment, the quenching should occur at a cooling rate within a range of 0.85 ° C / second and 2.0 ° C / second.

As further possibilities of quenching, for example, a quenching in water and / or an oil can be provided. Also, for example, it may be intended to perform various types of quenching, such as direct air blowing, quenching in water, and / or quenching with oil in sequential order. This can also be done

be provided that one or more of these mentioned methods, for example, also be carried out at different temperatures and recurring.

In one embodiment of the method, it may be provided that the tempering of the sintered part takes place within a temperature range of 150.degree. C. to 300.degree.

A preferred variant of the method provides that the tempering of the sintered part takes place within a temperature range of 180 ° C to 240 ° C.

The actual temperature and time chosen for tempering, during which tempering takes place, depends in particular also on the composition of the material.

In a further embodiment of the method, it can be provided that after the removal of the sintered part as a net-shape wing, a deburring of the net-shape wing takes place. In this case, deburring may be necessary, in particular, in that embodiment of the method in which a play of the tool is present during the pressing. In this case, a play of the tool may in particular be present in these cases, in which the first and / or the second contour surface are produced by means of a lower punch or upper punch. The deburring can be done, for example, by brushing, filing, grinding, milling, vibratory grinding, thermal deburring, electrochemical deburring,

Hochdruckwasserstrahlentgraten, pressure flow, hydroerosives grinding and / or cutting done.

In one embodiment of the method it can be provided that the powder mixture comprises the following constituents: Cu 0-5.0 wt .-%;

Mo 0.2-1.0 wt%;

Ni 0-6.0 wt%;

Cr 0-3.0 wt%;

Si 0-2.0 wt%;

Mn 0-1.0% by weight;

C 0.2-3.0 wt .-% and the remainder Fe. In a further embodiment of the method, it can be provided, for example, that the powder mixture comprises the following constituents:

Mo 0.2-4.0 wt%;

Cu 0-5.0% by weight;

Ni 0-6.0 wt%;

C .0.2-2.0 wt .-% and the remainder Fe. In a particularly preferred embodiment of the method, it can be provided, for example, that the powder mixture comprises the following constituents:

Mo 1, 2-1, 8% by weight;

Cu 1, 0-3.0 wt .-%;

C 0.4-1.0% by weight; as well as the remainder Fe. In a further preferred embodiment, it can be provided, for example, that the powder mixture comprises the following constituents:

Cr 0-3.0 wt%;

Ni 0-3.0 wt%;

Si 0-2.0 wt%;

C 0.2-3.0 wt%;

Mo 0.2-2.0 wt%; as well as the remainder Fe.

In a further preferred embodiment, it can be provided, for example, that the powder mixture comprises the following constituents:

Cr 0.8-1.2% by weight;

Ni 0.5-2.5% by weight;

Si 0.4-0.8 wt%;

C 0.4-1.0% by weight;

Mo 0.4-1.5% by weight; as well as the remainder Fe.

In a further variant of the method, it can be provided, for example, that the powder mixture comprises the following constituents:

Cu 1, 0-3.0% by weight;

Mo 1, 0-2.0% by weight;

C is 0.4-0.8% by weight;

0-2.0 wt .-% of one or more elements from the amount of {Ni, Cr, Si, Mn} and the remainder Fe.

The composition of a powder mixture of constituents with a remainder Fe is to be understood as meaning that, apart from small amounts of unavoidable impurities and / or compound constituents, no further elements and / or Compounds are present as the specified in the powder mixture, so that Fe fills the 100 wt .-% missing shares.

Furthermore, it can be provided that before pressing the powder mixture

Pressing aids are added. Such pressing aids can, for example

Lubricant, binder and / or plasticizer. These are additions to the powder mixture which, for example, facilitate the pressing of the powder mixture, facilitate the ejection of the compact from the press tool and / or other advantageous behaviors of the powder mixture during

mechanical and / or thermal impact result. In the above-mentioned compositions of the powder mixtures, these pressing aids are not taken into account. The quantitative values listed in the abovementioned compositions of the powder mixtures are therefore mentioned without consideration of any pressing aids which may be present, but do not exclude that before pressing the powder mixture in addition to the said compositions

Pressing aids are added.

In a further embodiment of the method can be provided that after pressing and before sintering as a further step, a thermal

Treatment of the green body is carried out with the aim of possibly existing

Remove pressing aids from the component. This is a process that can also be called dewaxing. In this case, it can be provided, for example, that the dewaxing of the green compact takes place within the same sintering furnace, in which the sintering of the green compact takes place. However, it may also be provided that the dewaxing is carried out in a furnace other than the sintering furnace.

In one embodiment of the method, it can be provided that the setting of the continuous and / or discrete temperature profile for dewaxing and / or sintering takes place in one or more stages.

As a way to make multiple or, preferably, all, the

Process steps of dewaxing and / or sintering and quenching and tempering in a same furnace can be provided, for example, that the entire temperature profile is set in a sintering furnace. It can also be provided that, in addition to the step of dewaxing and / or sintering as well as the quenching step, the annealing step is also carried out in the same furnace as the previous method steps. Again, one way to realize this is to set the entire sequence of sequential process steps

Implementation of the aforementioned process steps in a sintering belt furnace. It can be provided that the entire temperature profile is set along a running direction of the components to be sintered. Likewise, however, it can also be provided that individual steps of the temperature profile are adjusted position-independently as a function of time. A combination of these two may be provided.

Another aspect of the invention, which can be used depending as well as independently of the method described above, relates to a wing for a

Vane pump.

The vane for a vane pump has at least a first end face and a second end face oriented parallel thereto, a first side face and a second side face oriented parallel thereto and a first contour face and a second contour face. The wing here consists of a metallic sintered material. The surface of the wing is further open porous at least partially.

An at least partial presence of an open-pored surface of the wing is to be understood that at least on one of the six surfaces of the wing, that is, at least one of the first end face, the second end face, the first side face, the second side face, the first contour surface and the second

Contour surface is at least partially porous. Open - pore areas of the

Surface here are characterized in that the surface is not completely closed, but that in one of the usual dimensions of metallic sintered material on the surface pores are open.

In particular, the term "open-pored surface" may refer, for example, to an open-pore surface according to DIN 30910 part 3.

The advantage of a region with a surface that is not completely closed and therefore open-pored is in particular that the open-pored regions of the surface

For example, can serve as a lubricant film reservoir. As a result, for example, when using the wing in a vane pump, a transport of lubricating oil means serving as a lubricating film reservoir open-pored areas. Provided

At least the contour surface, which is provided for a frictional contact with an inner wall of the vane pump, has open-pore regions, the lubricant contact that is present through this can lead to improved lubrication over the region of the inner wall, whereby in particular reduced wear can be achieved.

In a particularly preferred embodiment of the wing, at least the surfaces provided for frictional contact with an inner wall of the vane cells and both end faces are open-pored at least in regions. In such a

Design of the wing can be an improved lubricant transport means of the open-pore areas of the surface of the wing in the interior of the

Vane pump done. The surface of the wing is preferably largely porous. Under a largely open-pored design of the surface of the wing is to be understood that at least 50 percent of the surface of the wing are porous.

In a particularly preferred embodiment of the wing, the entire surface, that is, the surface of all lateral surfaces of the wing, completely open-pored.

In one embodiment of the wing can be provided that the surface of the wing is at least partially free of abrasive marks. For example, sanding marks are caused by targeted sanding of the surface as part of a process

Post-processing of the wing to adjust the tolerances. Other possible reasons for grinding, for example, a surface treatment for setting a corresponding desired surface property, so that depending on the selected method of grinding and the abrasive, for example, a certain surface roughness of the component can be adjusted. In the presence of a net-shaped component, which already has the necessary for a use of the component without further post-processing, such a grinding is not necessary if the surface finish achieved makes the component suitable for the application. In the proposed wing in the described embodiment as trained without grinding marks wing results in addition to the unnecessary grinding through the resulting savings of effort and thus costs the further advantage that possibly open-pore areas of the wing their property of the open porosity not by any necessary grinding lose for a post-processing. Preferably, the surface of the wing is largely free of abrasive marks. The notion of a surface of the blade which is largely free from abrasion marks is to be understood as meaning that at least 50% of the surface of the blade is free of abrasive marks.

In a particularly preferred embodiment it can be provided that the

Surface of the wing is completely free of sanding marks.

In a preferred embodiment of the wing can be provided that the wing has a structure which is martensitic at least to a depth of 0.2 mm below the surface. The surface of the wing here denotes the

The totality of all surfaces of the wing, so that over the entire mantle of the wing of the wing has a martensitic structure. Preferred embodiments of the wing have a structure that is martensitic at least to a depth of 0.5 mm below the surface.

In particularly preferred embodiments of the wing can be provided that the wing has a martensitic structure over its entire volume, so that the wing is completely martensitic.

In a further embodiment of the wing can be provided that the martensitic structure of the wing is predominantly cubic martensitic. In this special embodiment of the martensitic microstructure there is the advantage that the cubic martensitic microstructure, as a special case of a martensitic microstructure, has internal tensions only to a comparatively small extent. This results in advantages for the dimensional accuracy of the wing; In particular, the likelihood of changes resulting from a reduction in internal stress is the

Dimensional accuracy reduced.

Particularly preferred may be provided a design of the wing, in which the martensitic structure of the wing is formed completely cubic martensitic. Especially in a formation of the martensitic microstructure as a completely cubic martensitic microstructure fluctuations of the tolerances are avoided as much as possible by a reduction of internal stresses. In a further embodiment of the wing it can be provided that the wing has a surface hardness with a value within a hardness range of 550 HV0.2 to 800 HV0.2. In particular, due to the formation of the martensitic structure, the surface hardness results in a value lying between these values, which is comparatively high. The advantage of these comparatively high hardness values is that usually a high degree of hardness is associated with a reduction in the wear during frictional contact. This can be achieved that an exchange of the wings is much less often necessary. The combination of the high hardness and the improved through the open-pore areas of the wing lubrication due to an improved distribution of lubricant can thus be achieved in the best case even a

Replacement of the blades during the entire life of the vane pump is not necessary.

Another aspect of the invention, which may be applied depending on the method and / or wing described above, relates to a vane pump having a control ring and a rotor eccentrically mounted in an interior of the control ring to the control ring. The rotor has in this case at least one slot-shaped guide, wherein the slot-shaped guide is preferably arranged in the radial direction. Here, an open-pore net-shaped wing is introduced in the slot-shaped guide. The wing is in this case movably mounted in the slot-shaped guide, so that the wing is pressed during rotation of the rotor against an inner wall of the control ring.

In one embodiment of the vane pump can be provided that in the interior of the control ring lubricant present with open-pore areas of

Surface of the wing come into contact, and these open-pore areas act as subsystems of a capillary system, which contributes to a distribution of the lubricant within the control ring. Another aspect of the invention provides for use of an open-pored net-shape wing in a vane pump. This is preferably a vane pump in a refinement of a lubricating oil pump of a motor vehicle engine or of a motor vehicle transmission. As a special embodiment of such a lubricating oil pump and as more

For example, an open-pored net-shape wing can be used: - in engine lubricating oil pumps for combustion engines, - in lubricating pumps for electric motors,

- in cooling pumps for electric motors,

- in lubrication pumps for hybrid drives,

- in cooling pumps for hybrid drives,

in actuation pumps for converter automatic transmissions,

- in lubrication pumps for converter automatic transmissions,

in cooling pumps for converter automatic transmissions,

in actuation pumps for dual-clutch automatic transmissions,

- in lubrication pumps for dual-clutch automatic transmissions,

- in cooling pumps for dual-clutch automatic transmissions,

- in actuation pumps for transfer cases,

- in lubrication pumps for transfer cases,

- in cooling pumps for transfer cases,

- in compressors for air conditioners.

Furthermore, it can be provided that an open-pore net-shape wing, for example, generally in pumps and / or compressors for other purposes

can be provided. The described method for producing a metal porous sintered material, preferably open-pored, net-shape wings can also for

Production of a metal porous sintered material, preferably open-pore, net-shape component can be provided, wherein any components can be produced by this method. All described embodiments of the method should therefore also be claimed for a completely independent of an embodiment of the component as a wing in a general manner.

Further advantageous embodiments and developments will become apparent from the following figures. However, the details and features of the figures are not limited to these. Rather, one or more features having one or more features from the above description may be linked to new designs. In particular, the following statements do not serve as a limitation of the respective scope, but explain individual features as well as their possible interaction with each other.

Show it: 1 shows a representation of a method for producing a wing made of a metallic sintered material for a vane pump according to the prior art; FIG. 2 shows another embodiment of a method for producing a wing made of a metallic sintered material for a

Vane pump according to the prior art;

Fig. 3: Method for producing a metallic sintered material

existing net-shape wing;

4 shows a further embodiment of a method for producing one of a

metallic sintered material existing net-shape wing for one

Vane pump;

Fig. 5: wing for a vane pump in an end view;

6 shows a method step of pressing another embodiment of a wing;

7 shows a further embodiment of a wing for a vane pump, representation in a perspective view;

Fig. 8: Representation of a process step of the pressing in another

design;

9 shows an illustration of a further embodiment of the flight j for a

Vane pump, shown in a perspective side view; Fig. 10: microsection of the wing for a vane pump;

Fig. 11: a vane pump for exemplifying a possible

Use of the wing for a vane pump.

Fig. 1 is an exemplary illustration of a possible method for producing a wing for a vane pump, as can be carried out according to the prior art. For example, wings for an oil pump on the market 8-speed automatic transmission manufactured in such a way. According to the method known from the prior art, in a first step punching 1 of a blank from a metal sheet takes place. This blank is a cuboid in the case of a wing for a vane pump. Following punching of the blank, milling 2 takes place, which is provided to form a contour surface on one, two or more side surfaces of the blank. After milling 2 of the wing to produce the final shape of the wing, hardening 3 takes place in a next step, followed by tempering 4 of the wing. As a result, there is a wing after tempering 4 and further cooling, if any. Due to the production-related tolerance fluctuations, the wing after tempering does not yet have the tolerances which are necessary for use of the wing in a vane pump. Instead, according to the prior art technique shown, it is usual to plan the manufacture of the wing so that after starting the wing 4, the dimensions of the wing are greater than those required for the application, in order to achieve a final finish to allow the use of necessary tolerances. For the

Post-processing is carried out in the embodiment of Fig. 1 to be taken, the prior art, the process after removal 5 of the wing from the furnace in which the tempering 4 was carried out, a fine grinding 6 of the wing. In order to remove possibly existing burrs, takes place in accordance with the

Technique generally still a post-processing of the surface, for example by deburring 7, as is the case in the illustrated representation of the exemplary embodiment of the method. A further embodiment of a method for producing a wing is shown in FIG. 2. The method illustrated in FIG. 2 is a method for producing a prior art wing made of a metallic sintered material, as described in WO 2006/123502 A1. Fig. 2 differs from Fig. 1 in that not a blank is punched from a sheet, but that instead the wing is made of a metallic sintered material. For this purpose, in a first step, a pressing 8, in the connection of which the geometry of the wing already exists, as it is desired for the use of the wing. After the pressing 8, the wing is then sintered as a so-called compact in a sintering furnace by means of a sintering 9 process step. On the sintering 9 towards a removal 10 of the wing from the used for sintering 9 of the wing sintering furnace takes place. This is followed by hardening 11 in a furnace provided for this purpose and tempering 12 following hardening 11 in general For example, the dimensions of the sash, even after manufacture by this prior art method, are too large for use in a vane pump. Therefore, according to the prior art, the process steps fine grinding 13 and deburring 14 are absolutely necessary, which the starting 12 and a subsequent this

Cooling are downstream.

3 shows an embodiment of a method as a method for producing a wing made of a metallic sintered material. According to the embodiment of such a method shown in FIG. 3, in a first step, pressing 15 of a powder mixture into a green compact takes place by means of a powder press. In a second

Step sintering 16 of the green compact within a sintering furnace to a sintered part with austenitic structure. Immediately following this process step of sintering 16 is hardening 17, which is carried out within the sintering furnace. For this purpose, it is necessary in a first step that the sintered part is largely or preferably completely austenitized. The Austenitisierung takes place by heating in a

Temperature range in which the powder mixture or the sintered part is present in an austenitic structure or converts into such. During the heating, it is provided that sintering 16 and austenitizing occur at least partially during sintering 16 in the same process, that is, sintering of the component to be sintered takes place at a temperature at which an austenitic structure is established or an existing one austenitic structure remains stable. Following austenitizing, the sintered article is cured by quenching the sintered article to a temperature below the martensite start temperature of the metallic sintered material. In this case, a sufficiently high quenching rate is brought about to result in a martensitic transformation of the austenitic structure. For this purpose, in a preferred embodiment, a quenching to a temperature within a temperature range of 100 ° C to 300 ° C take place, and this quenching preferably by means of a direct Luftanblasung done. After hardening 17, tempering takes place, the tempering 18 in the embodiment shown in FIG. 3 likewise taking place within the sintering furnace. Annealing 18 is followed by quenching subsequent heating, which must be done at a temperature which does not result in complete or even partial phase transformation of the blade. As a result of the tempering 18 takes place, after any intervening cooling, as a last step, a removal 19 of the wing, the wing is removed as a net-shape wing, that has its intended tolerances immediately after removal. The possibility of removing the wing as a net-shape wing, as it surprisingly in the featured and Developments described here is a significant innovation over the prior art.

FIG. 4 shows a further embodiment of a method for producing a wing made of a metallic sintered material. The method shown in Fig. 4 differs from the method shown in Fig. 3 in particular in that after a pressing 20, a sintering 21 and a still performed in the sintering furnace hardening 22 and tempering 23 with the subsequent removal 24 of the wing as additional process step yet a final deburring 25 takes place.

FIG. 5 shows an embodiment of the wing for a vane pump. The wing 26 is shown in the illustration shown in the plan view of a first end face 27. In each case at an angle of 90 ° to this first end face 27 and parallel to each other are at the first end face 27, a first side surface 30 and in parallel to this orientation, a second side surface 31 at. As fourth and fifth lateral surface of the body of the wing 26, the wing 26 further has a first

Contour surface 28 and a second contour surface 29. The first contour surface 28 and the second contour surface 29 are each arched in the embodiment shown outwardly, wherein the curvature is caused by a curvature of the edges, which the first end face 27 and the second end face, not shown with the first

Contour surface 28 and the second contour surface 29 have in common. Of the

The radius of curvature of these edges is the same here for the first contour surface 28 and the second contour surface 29 and furthermore for the edges common to both end surfaces. With a targeted adjustment of the radius of curvature, for example, when using the blade 26 in a vane pump that of the first contour surface 28 and the second contour surface 29, which is provided for movement in contact with an inner surface of the vane pump, be optimized for such a touch. Such an optimization can be carried out, for example, to the effect that with a centrifugal force-based pressing of the first

Contour surface 28 or the second contour surface 29 to the inner surface of the

Vane pump as close as possible to complete the two separated by the wing spaces is possible. To form the radius of curvature of the first contour surface 28 and / or the second contour surface 29, different embodiments of the method for producing a wing made of a metallic sintered material are possible. A method step of the pressing during the method for producing a wing made of a metallic sintered material, for example according to the sequence of operations depicted in FIG. 4, is shown in FIG. The method step shown here is an exemplary embodiment for the press 20 shown in FIG. 4

Procedural step. The wing 32 is placed vertically in a press, so that the first contour surface 33 in the arrangement shown in FIG

Tool concept is formed by a lower punch 36, while the second

Contour surface 34 is formed by a punch 37. Making the first one

Contour surface 33 and the second contour surface 34 takes place here by a force exerted by means of the lower punch 36 and the upper punch 37 pressure. At the same time, the first side surface and the second side surface of the wing are formed by the first side surface and the second side surface, as not visible here, the first

End face and visible in plan view of the image plane second end face are formed by the die 35. As a result of the orientation of the blade shown in FIG. 6 and the exertion of pressure by means of the lower punch 36 and the upper punch 37 on the first contour surface 33 and the second contour surface 34, the result is that deburring is necessary in many cases. The reason for this is in particular that the tool used, ie in particular lower punch 36, punch 37 and die 35, have a game against each other, so a relative mobility of the individual tools to each other is possible. Such deburring is shown as deburring 25, for example, in the process sequence shown in FIG.

FIG. 7 shows a further embodiment of a wing 38. The wing 38 is in this case similar to the wing shown in FIG. 6 and has in common with the wing shown in FIG. 6 in common that the first contour surface 39 and the second contour surface 40 common edges with the first side surface 42 and the non-visible second Have side surface, and that these contact edges are the longest contact edges of the wing 38. The shortest contact edges, however, are the contact edges of the first contour surface 39 with the first end face 41 and the non-visible end face and the contact edges of the second contour surface 40 with the first end face 41 and the second end face not visible. In this ratio of the tolerances of the edges and the orientation of the wing to the upper pressing direction, which is represented by the arrow 43, and to the lower pressing direction, which is represented by the lower arrow 44, is a deburring, as for example in the embodiment of 4 is shown as deburring 25, in many cases necessary. In Fig. 8 is another embodiment of a method step of pressing the

Manufacturing a made of a metallic sintered material wing 45 shown. The wing 45 is oriented in the illustration of Fig. 8 such that the first side surface 48 is visible in the plan. In the embodiment shown, during the

Process step of pressing the first end face 51 by means of the upper punch 50 and the second end face 52 formed by means of the lower punch 49. In this embodiment of the method step of the pressing as part of the method for producing a net-shaped wing made of a metallic sintered material, the first contour surface 46 as well as the second contour surface 47 is formed by the die 53. The pressing direction in this case runs in the axial direction along the longitudinal axis, which is oriented parallel to the pressing direction formed by the upper punch 50 and the lower punch 49. The embodiment of the method step of the pressing shown in FIG. 8 aims in particular at an immediate pressure effect on the

Long side of the wing 45, wherein the longitudinal side is the longest side of the wing 45 and in the embodiment shown as edge surfaces between the side surfaces 48 and the non-visible side surface with the contour surfaces 46, 47 to understand. In such an approach, it is possible to also form much more complex contours in the first contour surface 46 and / or the second contour surface 47. A further advantage of this embodiment of the method step of pressing is that in many cases deburring is not necessary, so that in the embodiment of the pressing method step shown in FIG. 8, in many cases, a method for producing a metallic sintered material is provided. shape wing without a after removal of the sintered part as a net-shape wing deburring deburring is possible. The method step illustrated in FIG. 8 is comparable, for example, as a pressing step according to the embodiment of the method for producing a wing shown in FIG. 3.

In another embodiment of the wing 54, the upper pressing direction is represented by the arrow 58 and the lower pressing direction by the arrow 59 in a perspective side view. The upper pressing direction here indicates the direction in which pressure is applied to the first end face 56, while the lower pressing direction indicates the direction in which pressure is exerted on the second end face, not shown.

Fig. 10 is an example of a microsection of the net-shape wing shown in Fig. 9, so after its removal, to be taken in longitudinal section. The structure is martensitic, with the martensitic structure being completely cubic. FIG. 11 shows an exemplary embodiment of a vane pump. The vane pump has a rotor 60 which is disposed within a control ring 61. Within the control ring a number of seven wings is arranged in slot-shaped guides, for example wings 62, which is arranged in a slot-shaped guide such that the first end face 63 lies in the plane of the paper, and the first contour surface 64 of the wing 62 on an inner wall of the control ring and thus an inner wall of the vane pump is positioned adjacent. Due to the movable mounting of the wings in the slot-like guides of the rotor, a seal of the space between the first contour surface 64 and the inner wall of the vane pump is effected upon rotation of the rotor and thereby acting on the wings centrifugal force.

Claims

claims

A method of making a metallic sintered material

existing, preferably open-pore, net-shape wing (26, 32, 38, 45, 54, 62) for a vane pump, wherein the wing (26, 32, 38, 45, 54, 62) at least a first end face (27, 41 , 51, 56, 63) and a second end face (52), preferably oriented parallel to the first end face, and a first side face (30, 42, 48, 57) and a second side face (31) oriented parallel thereto, and also further, the wing (26, 32, 38, 45, 54, 62) a first

Contour surface (28, 33, 39, 46, 55) and a second contour surface (29, 34, 40, 47), and wherein the method for producing the wing (26, 32, 38, 45, 54, 62) at least the following steps include:

^■ pressing (8, 15, 20) of a powder mixture into a green body by means of a powder press,

^■ sintering (9, 16, 21) of the green compact within a sintering furnace into one

Sintered part with austenitic structure,

^■ quenching the sintered compact within the sintering furnace to a temperature below a martensite start temperature of the sintered compact for curing (3, 1 1, 17, 22) of the sintered compact,

^■ tempering (4, 11, 18, 23) of the sintered part, preferably within the

Sintering furnace,

Removal (5, 10, 19, 24) of the sintered part as a net-shape wing (26, 32, 38, 45, 54, 62), preferably as a removal (5, 10, 19, 24) from the sintering furnace.

A method according to claim 1, characterized in that the pressing (8, 15, 20) of the wing takes place by the first contour surface (28, 33, 39, 46, 55) by means of at least one lower punch (36, 49) of the powder press and the second

Contour surface (29, 34, 40, 47) by means of at least one upper punch (37,50) of the powder press is formed under pressure and the first end face (27, 41, 51, 56, 63), the second end face (52), the first Side surface (30, 42, 48, 57) and the second side surface (31) are formed by at least one die (35, 53) of the powder press. 3. The method according to claim 1, characterized in that the pressing (8, 15, 20) of the wing (26, 32, 38, 45, 54, 62) takes place by at least the first Contour surface (28, 33, 39, 46, 55) and the second contour surface (29, 34, 40, 47) are formed by a die (35, 53) of the powder press and further one or more of the first side surface (30, 42, 48, 57), the second

Side surface (31), the first end face (27, 41, 51, 56, 63) and the second end face (52) by means of a lower punch (36, 49) and an upper punch (37,50) of the powder press are formed under pressure.

4. The method according to any one of the preceding claims, characterized in that the sintering (9, 16, 21) within a temperature range of 1050 ° C to 1300 ° C, preferably from 1100 ° C to 1150 ° C, takes place.

5. The method according to any one of the preceding claims, characterized in that the quenching to a temperature within a temperature range of 100 ° C to 300 ° C, preferably by means of a direct Luftanblasung.

6. The method according to any one of the preceding claims, characterized in that the tempering (4, 11, 18, 23) of the sintered part within a

Temperature range of 150 ° C to 300 ° C, preferably within one

Temperature range from 180 ° C to 240 ° C, takes place.

7. The method according to any one of the preceding claims, characterized in that after the removal (5, 10, 19, 24) of the sintered part as a net-shape wings (26, 32, 38, 45, 54, 62) a deburring (7, 14, 25) of the net-shape wing (26, 32, 38, 45, 54, 62) takes place.

8. The method according to any one of the preceding claims, characterized in that the powder mixture comprises the following components:

Cu 0-5.0% by weight;

Mo 0.2-4.0 wt%;

Ni 0-6.0 wt%;

Cr 0-3.0 wt%;

Si 0-2.0 wt%;

Mn 0-1.0% by weight;

C 0.2-3.0% by weight as well as the remainder Fe.

A method according to claim 8, characterized in that the powder mixture comprises the following constituents:

Cu 1, 0-3.0 wt .-%;

Mo 1, 0-2.0% by weight;

C is 0.4-0.8% by weight;

Vane (26, 32, 38, 45, 54, 62) for a vane pump, comprising at least a first end face (27, 41, 51, 56, 63) and a second end face (52) oriented parallel thereto, a first side face (12) 30, 42, 48, 57) and a second side surface (31) oriented parallel thereto and a first contour surface (28, 33, 39, 46, 55) and a second contour surface (29, 34, 40, 47), wherein the Wing (26, 32, 38, 45, 54, 62) consists of a metallic sintered material, and wherein a surface of the wing (26, 32, 38, 45, 54, 62) at least partially, preferably largely, particularly preferably completely, open-pored is.

Wing (26, 32, 38, 45, 54, 62) according to claim 10, characterized in that the surface of the wing (26, 32, 38, 45, 54, 62) at least partially, preferably for the most part, more preferably completely free of grinding marks is.

Wing (26, 32, 38, 45, 54, 62) according to claim 10 or claim 1 1, characterized in that the wing (26, 32, 38, 45, 54, 62) has a structure which extends at least up to a depth of 0.2 mm below the surface, preferably to a depth of 0.5 mm below the surface, most preferably completely, is martensitic.

13. wing (26, 32, 38, 45, 54, 62) according to claim 12, characterized in that the martensitic structure is formed predominantly, preferably completely, cubic martensitic.

14. wing (26, 32, 38, 45, 54, 62) according to any one of claims 10 to 13, characterized in that the wing (26, 32, 38, 45, 54, 62) has a surface hardness with a value within a Hardness range of 550 HV0.2 to 800 HV0,2 has.

15. vane pump with a control ring (61) and in an interior of the control ring (61) to the control ring (61) eccentrically mounted rotor (60), wherein the rotor (60) has at least one, preferably arranged in the radial direction, slot-shaped guide and wherein an open-pored net-shape wing (26, 32, 38, 45, 54, 62) according to any one of claims 10 to 14 is incorporated in the slot-shaped guide, wherein the wing (26, 32, 38, 45, 54, 62) is movably mounted in the slot-shaped guide, so that the wing (26, 32, 38, 45, 54, 62) is pressed against an inner wall of the control ring (61) during rotation of the rotor (60).

16. vane pump according to claim 15, characterized in that in the

Inside the control ring (61) existing open-pore lubricant

Areas of the surface of the wing (26, 32, 38, 45, 54, 62) come into contact, and these open-pore areas act as subsystems of a capillary system, which contributes to a distribution of the lubricant within the control ring (61).

17. Use of an open-pore net-shape wing (26, 32, 38, 45, 54, 62) in a vane pump, preferably a vane pump in a refinement of a lubricating oil pump of a motor vehicle engine or a motor vehicle transmission.