EP1354135B1 - Miniature precision bearings for minisystems or microsystems and method for assembling such systems - Google Patents

Abstract

The aim of the invention is to obtain a cost-effective solution for providing a microsystem with bearings, which have sufficiently high precision and long-term stress resistance. The invention proposes a method for manufacturing, adapting or adjusting a bearing portion in a fluidal microcomponent (M) comprising a stator (30) and a rotor (40,2). Said rotor is rotatably supported on the at least one bearing portion (L10,L11) relative to said stator. Said rotor (40,2) is rotatably supported by a sleeve (10, 11) inserted into said stator (30), for forming said bearing portion, the at least one sleeve being inserted in said stator as a bearing sleeve and comprising an inner surface and an outer surface (10i, 10a; 11i, 11a). Before being inserted in said stator, said bearing sleeve (10, 11) is a separate bearing component comprising an inner surface (10i, 11i) as an inner bearing surface, which is mechanically micro-finished before being inserted into said stator (30). The outer surface (10a, 11a) of said bearing component (10, 11) is mechanically permanently connected with said stator (30).

Description

The invention relates to a microsystem and a method for manufacturing, adjusting or adjusting a bearing in a miniature to microsystem.

Such a microsystem is described in WO-A 97/12147 (Fraunhofer) as, for example, a micropump or micromotor. To promote a fluid or to be driven by a fluid is the operation of the pump or the motor. Bearings exist there and must be designed appropriately or become.

Due to the small nominal dimensions for the microsystems, to which reference is made, for example, to the true to scale drawing of Figure 1, there is an increased requirement for the storage of external wheels, internal wheels or shafts, which are collectively referred to as "rotors". Especially when passing (conveying or driving) non-lubricating media, there is a need to use very hard and at the same time corrosion-resistant materials, e.g. Ceramic or carbide. The use of these materials makes sense in all tribologically stressed functional components of the microsystem in order to avoid the use of soft or corrosive materials with a constant or greater wear. Especially with small and smallest dimensions in the millimeter range (Minibis microsystem) wear in the storage area quickly leads to failure of the entire system.

Added to this is the manufacturing side, which brings with such low nominal dimensions difficulties, to comply with the high accuracy required dimensions permanently. These dimensional accuracies are in the micrometer range, with required accuracies being in the range of 1 to 2 μm. Especially the use of eccentrically operating microsystems, consisting of two intermeshing rotors, so-called. Internally toothed micropumps according to the gerotor principle, requires the highly accurate compliance with the eccentricity, which is achieved by two eccentrically arranged bearings. The bearing thus having a radial offset also have an axial offset, but are axially close to each other. The axes of the two sleeves are inherently offset from one another eccentrically. This eccentricity requires an accuracy in the micrometer range, which is complicated to manufacturing technology with the use of cutting manufacturing processes with conventional housing construction consuming.

The object of the invention is accordingly to propose a cost-effective solution in order to provide a microsystem of the type shown in FIG. 1, for example, with bearings which have the required highest accuracy as well as a long-term strength, in particular when operating with non-lubricating fluids.

This object is achieved with a microsystem according to claim 1 or a manufacturing method, fitting method or setting method according to claim 7 for producing at least one bearing point of said microsystem.

According to the invention, a mechanically precise overall system of simple precise bodies (sleeves) and a "inaccurate" manufactured housing (stator) by connecting technology (soldering, gluing, press-fitting) constructed inexpensively, especially in connection with two axially spaced bearings or bearings and in an order of magnitude of the "rotors" to be stored in a diameter range of less than 15 mm, although larger versions should not be ruled out, but the smaller diameters should receive increased attention.

In the context of the explanation of the invention, reference is made both to the microsystem, as well as to the method for producing the bearing of the microsystem, in which process variant the microsystem is described negatively in the sense that spaces and bearings are created, in which this microsystem then can be used positively. If the microsystem itself affected, the finished state is described, in which the manufacturing process is only indirectly recognizable, as can be seen from the following explanation in support of the claims.

It must be predicated on claims 1 and 7 that the terms of a "hard" bearing material be compared with those of a "soft" stator material. The terms should be understood to mean that the hard bearing material is, for example, ceramic or cemented carbide to ensure long term strength and long term accuracy of the at least one bearing. Compared to these hard materials, the easier to be machined to be machined softer stator materials meant that are cheaper to obtain and can be easily processed manufacturing technology. They accommodate the essentially small bearing components, which provide accuracy and abrasion resistance to solve the problem (claim 1).

The stator has at least one section made of a material that is easier to machine with a cutting edge and that receives at least one bearing body made of the hard material. In the bearing body, preferably a sleeve, the rotor is mounted either as a shaft or as an outer rotor or inner rotor.

Between the hard material and the stator material, there is a region which establishes the mechanically strong connection, which can be obtained in three ways. If a part of the housing material is displaced in the bearing area with a mechanical pressing operation, an immediate mechanically strong connection leads to the holding of the bearing component in the sense that after insertion a mechanically fixed connection of the bearing component to the stator exists and the bearing component is precisely aligned (claim 6) ).

An alternative variant for the production of the mechanically strong connection consists in the temporally proceeding curing of a filler material which is inserted into a gap which exists between the bearing component and the slightly larger inner dimension of the receiving portion of the stator (claim 5). This gap can be in the range between 20 μm and 70 μm, in particular below 100 μm. After curing, there is a composite of materials that is mechanically stable, durable and durable. In addition, the realization of the thus formed at least one bearing point is inexpensive.

A third variant lies in the combination of the two methods described above, when two axially spaced bearings are provided (claim 3). Then, for press-fitting in a mechanical pressing operation with direct mechanical fixed connection for holding the first bearing component, hardening of a filler material between the second bearing component and the stator can be used.

First, the first bearing is pressed mechanically displacing the soft material (claim 8). Subsequently, the second bearing is first loosely inserted into the stator, supported by the already mechanically fixed bearing whose center is axially spaced. A subsequent position positioning of the second bearing relative to the first bearing and thus also the absolute positioning of the second bearing relative to the stator follows and a hardening filler ensures after introduction between the second bearing and the stator for the temporally going to hardening and fixing (claim 9) , The adhesion action forms in a gap which is left between the second bearing and the stator, as described above.

Preferably, the first bearing point which is mechanically positioned by displacement of a surface portion of the stator, that of a shaft, wherein the outer diameter of the bearing forming the sleeve has a smaller diameter than the sleeve which forms the subsequently defined second bearing point by curing a Filling material is accurately positioned (claim 4 or 11 or 12).

The displacement or filling with a hardening material is the area which is to be described as "non-conformity" (feature (a), claim 7). The mismatch becomes a fit during the manufacturing process. Either the mismatch is achieved by a mechanical displacement of a part of the stator material (claim 5,6), or the mismatch becomes a mechanically strong connection by providing a hardening intermediate material which reaches the mechanically strong connection as filler material (claim 9).

When pressing in, the bearing body is guided with high precision during the entire pressing process in order to ensure a positionally accurate recording in the stator. During mechanical guiding and during the displacement process, at least the surface of the stator section which receives the bearing component is changed, in particular more than the surface, or a radial piece is displaced (claim 6).

Without displacement, the curing of the filler works (claim 5.9), wherein the bearing member is held accurately during curing in order to make the mechanically strong connection to a precise positional precise connection.

The at least one bearing body which was a separate bearing body made of a different material before completion of the production, is machined by a mechanical fine machining of the inner surface, such as grinding, honing or lapping, that a suitable bearing surface for the shaft or the outer rotor arises. Particularly rotationally symmetrical bearing body are suitable for grinding operations, such as centerless grinding, and comparatively inexpensive to produce the necessary precision. The grinding also allows the machining of hard materials without restriction, whereby the choice of materials is not limited. After the high-precision production of the bearing surfaces, the mechanical connection is made with the stator, wherein the introduction of the bearing sleeves and their mutual alignment, in particular by gluing or pressing, done with a separate device, which Location and orientation of the one, preferably defined by two eccentric bearings (claim 2,14) and achieved the necessary tolerances with relatively little effort.

Before curing of, for example, solder or adhesive as a curable material, the adjustment carried out the sleeves can be made to each other, so that they initially move floating in the filled gap with curable material and align.

With a holding device, the layer is stabilized and secured during the progressive hardening of the solder or adhesive.

The manufacturing method advantageously restricts the variety of parts in a modular system with different rotor sizes of the gerotor pump, since with different gears - defined by an eccentricity and the toothing parameters - the same bearing body can be used.

When pressing is carried out with a slight interference fit, in which the manufacturing tolerance of a "not sufficiently precise", for example, machined (under chip formation) produced stator defines the excess of the fit. Since the tolerance of the position of the negative mold in the housing usually does not correspond to the predetermined position of the corresponding bearing body, the material is displaced during the pressing process (claim 8). This process is asymmetric in most cases and is made possible by the roughness or a defined low contact ratio of the surface of the negative mold. The roughness of the surface to be produced is adjusted so that tips of the surface carrying the bearing body to be pressed in can be displaced relatively easily. Alternatively, the surface is also made possible by a defined axial or radial structure (comparable to a wooden dowel). The radial offset to be compensated can amount to approximately 10 μm to 20 μm between the bearing body and the section of the stator receiving it.

The principle of storage can be transferred to other mechanical systems with defined bearings, such as external gear pumps, etc., so that not necessarily only eccentric axes with two bearing points are affected by the invention (claim 2).

The rough specification of the position of the bearing body is inexpensively by cutting processes (turning, milling or the like) or urformend (eg by injection molding), deforming or predetermined in other manufacturing processes. The recesses (the negative forms) have only limited accuracy, so they can have greater tolerances than directly introduced bearings. Already here shares of manufacturing costs are saved to then achieve the precise and accurate position of the bearing body to each other by means of the mounting device, the highly accurate placed the hard bearing body in the comparatively soft stator and sets micrometer accurate against each other in position and orientation.

A separately essential mounting device, which is also described below, has a decisive influence on all assembly operations. It defines the eccentric position of the two sleeve axes to each other by their mikrometerexakte geometry and stabilizes this position during the assembly process, either during pressing, or during the holding time during curing of the joining material.

The execution of a storage corresponds to a so-called. Flying (one-sided) storage. The one-sided bearing is closer to the drive, as the remote part of the storage, which is occupied by the microsystem. With one-sided storage, the number of bearings requiring accuracy is reduced. Thus, by the use of a rotor (outer rotor, inner rotor or shaft) receiving bearing sleeve, the radial bearing of the rotating functional element can be ensured. If two bearings are provided, which are arranged eccentrically to one another, the bearing body serves for the formation of the shaft bearing as an axial support for the outer rotor of the microsystem. For this purpose, the inner diameter of the bearing body for the shaft is smaller than the inner diameter of the bearing body for the outer rotor of the microsystem. The fact that the outer diameter of the bearing body for the shaft is larger than the inner diameter of the bearing body for the outer rotor, creates an axial bearing surface. The outer rotor (and also the inner rotor) are thus on the axial end face of the smallest inner diameter having bearing member. It forms between the two bearing components, a strip which has no constant width in the circumferential direction due to the eccentricity.

The eccentric sleeves abut one another along their entire circumference (on at least one inner surface) and are in particular attached to an axial end section, that is to say on an end face of the stator. At the other end of the stator, a coupling device is provided which creates a connection to a motor device in the sense of a drive.

When talking about a radially offset bearing and an axially offset bearing, reference may be made to the respective centers. In the radial displacement, the axes are offset from each other, for which the parameter "dr" stands. An axial offset corresponds to a distance of the centers of the bearings, wherein the distance is denoted by dL. However, the two bearings themselves have a finite axial length, and they are closely adjacent, especially immediately adjacent to each other.

The limited spatial dimension of the bearings also allows the use of highly specific and expensive materials for the bearings without unduly increasing the cost of the overall system.

In the mechanical finishing, based on the separate bearing component, which has a suitable inner bearing surface before insertion, a perpendicularity of this inner bearing surface relative to an end face of the bearing component can be observed. A perpendicularity is advantageous for an additional auxiliary bearing in the sense of a mechanical support point during assembly of the bearing points (claim 14).

A further adjustment possibility is provided in the axial direction when it can already be assumed that the first bearing point is a finished first support point (claims 11 to 13). The height (measured in the axial direction) of the bearing for receiving the rotor, so the second bearing point, while manufacturing technology can be adjusted exactly opposite the stator so that a defined frontal play can be achieved. The front play refers to the rotor used later, which is rotatably mounted in the second bearing. With the front play friction and fluidic storage can be specified. The inner opening of the stator, in which the at least one bearing point, preferably two axially spaced bearing points are used, has two sections, which each form an inwardly facing surface. These surfaces are not yet suitable for storage surface sections on which by gluing, pressing or a combination of these joining techniques, the bearings are mounted by the manufacturing technology more accurate bearing sleeves. These two surface portions of the stock are already aligned eccentrically to each other to form a respective axis having a center distance in the radial direction of "dr".

The inner receptacle thus has two functional sections, for receiving two functionally different bearing points with respective bearing body. A Compensation function by pressing or gluing then acts in a very small range, with an eccentricity is gear-dependent, for example, 180 microns, in which example, an adhesive gap has a magnitude of not more than 70 microns and a pressure then has about 10 microns oversize.

Figur 1

veranschaulicht in Originalgröße mit einem Maßstab 1:1 das vollständige Mikrosystem 1, bestehend aus einen Fluidanschluß F, der eigentlichen fluiddurchsetzten Mikrokomponente M, z.B. als Pumpe mit motorischem Antrieb A, oder als fluidischer Motor M mit Antriebsobjekt A.

Figur 1a

veranschaulicht in starker Vergrößerung eine Explosionsdarstellung der Figur 1 mit allen im folgenden näher zu beschreibenden Komponenten, wobei die Mikrokomponente M aus einem Innenrotor 3 und einem Außenrotor 2 besteht, welcher Innenrotor auf einer Welle 40 aufgesetzt ist. Diese Mikrokomponente ist in der eingangs beschriebenen WO-Schrift näher erläutert und soll daher im folgenden als Gerotor-System bzw. als innenverzahntes Zahnringsystem mit miteinander kämmenden Zähnen bei der Drehbewegung bezeichnet werden.

Figur 2

ist eine Schnittdarstellung entlang der Hauptachse der Figur 1a und veranschaulicht den Zusammenbau des Zahnringsystems mit allen Komponenten.

Figur 3

veranschaulicht einen Schnitt entlang der Mittelachse des in den vorigen Figuren bezeichneten Systems, wobei nur der Stator 30 als Gehäuse schematisch dargestellt ist, zur Veranschaulichung der hier eingesetzten Hülsen 10,11 als Lagerstellen.

Figur 3a

veranschaulicht die Oberflächen 30i und 10a von Lagerhülse 10 und Stator 30 vor und nach dem Einsetzen der Hülse.

Figur 4

veranschaulicht ein Stütz- und Positioniersystem 50 für die Einbringung der Hülsen 10,11 von Figur 3.

Figur 5

veranschaulicht perspektivisch die Figur 3 mit dem Stator und davon noch beabstandet, also vor dem Einsetzen das erste Hülsenteil 10 und das zweite Hülsenteil 11 zur Aufnahme der Welle 40 im Wellenraum W und des Außenrotors des Mikrosystems im Rotorraum R. Beide Teile werden in Richtung s in den dafür vorgesehenen Innenraum 31 des Stators eingesetzt.

Figur 6

veranschaulicht eine alternative Justage und Befestigung der Hülsen 10,11 von Figur 5, verglichen mit Figur 3a.

Figur 7

veranschaulicht eine Aufsicht in Achsrichtung auf die Figur 3, noch ohne eingesetzten Rotor und ohne eingesetzte Welle 40, zur Veranschaulichung der axialen Lager- und Stützfläche 10b.

Exemplary embodiments explain and supplement the claimed invention.

FIG. 1

illustrates in full scale scale 1: 1 the complete microsystem 1, consisting of a fluid port F, the actual fluid-penetrated micro-component M, eg as a pump with motor drive A, or as a fluid motor M with drive object A.

FIG. 1a

FIG. 1 is an enlarged exploded view of FIG. 1 with all the components to be described in more detail below, wherein the microcomponent M consists of an inner rotor 3 and an outer rotor 2, which inner rotor is mounted on a shaft 40. This microcomponent is explained in more detail in the WO document described above and is therefore to be referred to below as a gerotor system or as an internally toothed ring gear system with intermeshing teeth in the rotary motion.

FIG. 2

is a sectional view along the main axis of Figure 1a and illustrates the assembly of the toothed ring system with all components.

FIG. 3

illustrates a section along the central axis of the system referred to in the previous figures, wherein only the stator 30 is shown as a housing schematically, to illustrate the sleeves used here 10,11 as bearings.

FIG. 3a

illustrates the surfaces 30i and 10a of bearing sleeve 10 and stator 30 before and after insertion of the sleeve.

FIG. 4

FIG. 3 illustrates a support and positioning system 50 for the insertion of the sleeves 10, 11 of FIG. 3.

FIG. 5

3 illustrates in perspective the figure 3 with the stator and still spaced apart, ie before insertion, the first sleeve part 10 and the second sleeve part 11 for receiving the shaft 40 in the shaft space W and the outer rotor of the microsystem in the rotor space R. Both parts are in direction s in used for the designated interior 31 of the stator.

FIG. 6

FIG. 3 illustrates an alternative adjustment and attachment of the sleeves 10, 11 of FIG. 5, compared with FIG. 3a.

FIG. 7

illustrates an axial view of the figure 3, still with no rotor inserted and without inserted shaft 40, for illustrating the axial bearing and support surface 10b.

The microsystem of Figure 1 in its original size shows the requirements for miniaturization and the need to manufacture bearings provided in this system with high precision and to ensure their durability and abrasion resistance.

FIGS. 1a and 2 shall be described together in order to obtain an insight into the microsystem illustrated in FIG.

The largest section is occupied by a drive system A, which is coupled to the microcomponent via a flange area. A shaft of the motor is coupled via a coupling 23 to the shaft 40 of the microcomponent torsionally rigid or rotationally fixed. The designated interior 32 is bounded by a sleeve 21 which extends axially longer than the coupling 23 has in length. In the region of the shaft 40, a first hat-shaped seal 24 is provided with a collar-shaped projecting thin flange portion, which seal 24 has an opening for the passage of the shaft 40. The seal is seated in an axial interior 31, in which also a first bearing sleeve 10 is placed, which also has an inner opening, in which the shaft 40 is suitably mounted for its rotation.

Above the first sleeve 10, a second, from the outer diameter ago larger sleeve 11 is provided, which has a larger inner opening for receiving the rotor or the rotors 2, 3 of the microsystem M, one of which rotatably placed on the shaft 40 via a pin 40a is.

Upon rotation of the shaft, both internally toothed rotors also rotate, for which purpose the outer bearing of the outer toothed ring is provided on the second sleeve 11.

The second sleeve 11 has an axially much shorter extension, but a larger radial inner recess, while the first sleeve 10 has a suitable for the shaft small bore, but on an axially greater length.

The microcomponent described is generally designated M, but consists of the two internally toothed rotors 2 and 3 shown in FIG. 1a.

Said sleeves 10, 11, seal 24 and shaft 40 are received in a stator 30, which may be considered as a portion of the housing. He has a long-extending flange portion 30 b, which extends over the Distance sleeve 21 extends on the outside and the edge of the drive A for fixing engages, and a further upper portion 30a, in which the storage of the Mikrosytems M and the shaft 40 takes place. The stator 30 is bolted directly to the engine. Electric small motors have a uniform thread or connection holes, which are usually attached to the engine transmission otherwise.

The inner opening of the second sleeve 11 for receiving the microsystem M is arranged in the stator at its end face. The sleeve can be mounted flush with the end face of the stator 30. Preferably, a small projection can be provided to achieve a better sealing effect on the rotors when the overlying portion 29 29 ', which contains the fluid guide to the terminals F, with a greater pressure via a screw 28 to the stator 30 with intermediate Sealing ring 25 and a kidney plate 25 a is pressed. For this purpose, a left-hand thread is preferably provided between the screw flange 28 and the stator 30, which is arranged on the outside. The screwing is done with a special claw key, which engages in a lateral bore. This can prevent unauthorized opening. The section 29 29 'contains the fluidic control contours (inlet opening and outlet opening) and is aligned with its lower portion 29' via a cylindrical pin 22 for engagement in a fitting opening 22a in the stator 30 and possibly a collar on the stator 30 exactly (radially and circumferentially) ,

The described flush bearing of the lower portion 29 'of the fluid guide portion 29, 29' with its drive-oriented surface on the rotors of the fluid system M is improved when a balancing ring 27 is provided between the clamping assembly 28 and the fluid guide portion 29 annular. This compensating ring 27 is made of a soft material, such as aluminum, copper or plastic and ensures that the portion 29 'is flush and flush with the likewise provided with an O-shaped seal 25 or an additional disc 25a with fluid-carrying kidney stator, in particular also on the outwardly facing end faces of the rotors in order to achieve a better sealing effect here. Due to the higher surface pressure (the richer concern) of the fluid guide portion 29 'against the second sleeve 11, the better sealing effect is achieved, which is favored by the soft balance ring 27.

From the above description, three structural sections can be seen. The fluid guide section F with the likewise to be regarded as a stator components 28,29,29 '. The actual stator 30 in the portion 30a for receiving the Microsystem with subsequent coupling portion 23 of the shaft 40 in section 30b. The drive area A adjoins this area.

It should be emphasized that a separation of the fluid-guiding section 28, 29, 29 ', F, provided by the assembly, takes place in the stator from the microsystem and this separation is located on the side of the rotors of the microsystem remote from the bearing side. In other words, the stator 30 is constructed so that the storage is placed flush with the facing away from the drive A end face, so that a placement of the fluid guide portion 29,29 'immediately adjacent to the fluidic microcomponent and with a proposed fluid guide structure of kidneys and Holes a passage and the functional operation of the micro-component M ensures.

The overview given above is intended to increase the empathy, as a microsystem of Figure 1 is constructed constructively. In the following, details are explained, which describe in particular the attachment and assembly of the first and second sleeves 10, 11 from FIG. 2, for which reference is made to FIG.

Figure 3 is a section through the axis of the system of Figure 2 showing two staggered axes 100 and 101. The axle offset is denoted by dr. The axis 100 is that axis of the first sleeve 10 which has a length L10. The sleeve is made of a hard material, such as carbide or ceramic. It is initially not inserted into the stator 30, which has an elongated opening 31 for its receptacle, the lower portion has an inner surface 30i. This inner surface can be seen schematically in FIG. 3a (in the lower field). It has a large roughness, which can arise during a cutting process. It does not have to have any particular accuracy and can even be made larger, as can be seen from FIG.

In the same way, another, axially above receiving portion in the stator 30 is provided as part of the opening 31, for receiving the second sleeve 11, which may also be made of a hard material such as ceramic or hard metal. She too is not used at first.

The use of hard materials, compared to the "soft" materials of the stator 30 secures the bearing sleeves against abrasion. They are spatially of a small extent, so that even expensive materials can be used. The Bearing sleeves are designed primarily as a hollow cylinder and have a respective interior, for receiving the respective "rotor".

The first sleeve 10 has an inner space with an inner surface 10i for receiving the shaft 40. The inner space is designated W and has a longitudinal extent corresponding to the sleeve length L10.

The axially adjoining second sleeve 11 is provided for receiving and supporting the outer rotor 2. It has for this purpose a rotor mount R whose diameter d11i is greater than the diameter d10i of the shaft space W. The inner surface 11i is designed so that a bearing of the rotor is possible. The inner surface 10i of the first sleeve part 10 is also designed so that a bearing of the shaft 40 is possible

Both surfaces are highly accurate and designed for their respective bearing function by grinding, eroding, honing or lapping.

The insertion of the two bearing sleeves in the corresponding axial portion of the opening 31 of the stator 30 with the inner surface 30i and the radially larger inner surface 30i 'is made with the insertion device of Figure 4 .

Here, the two sleeves 10,11 by spacers 53,52 spatially aligned with each other geometrically, which ensures the high precision. Both placeholders 52, 53 are spatially fixed relative to a support plate 51. The placeholder 52 for the outer rotor takes on the second sleeve 11, wherein the placeholder fills the rotor geometry of the rotor space R. The second placeholder 53 for the shaft 40 is axially longer. He takes over the filling of the shaft space W and places the first sleeve 10 spatially geometrically so that the two spaced axes 100,101 is obtained for the eccentric mounting of the existing of two rotors microsystem M. An unillustrated pin on the support plate 51 allows its absolute location fixation relative to the stator 30, for engagement in the recess 22a.

After the sleeves 10,11 are placed on the inserter 50 and its two radially displaced placeholders 52,53 "dr", the inserter with a mechanical arrangement (not shown) is geometrically and massively precise, even highly precise the intended opening 31 of the stator 30 is inserted axially. The thrust path s or thrust direction s produced in this case is shown in FIGS. 5 and 3a. Due to the dimensioning and the Surface structure of the two sleeves 10,11 and the inner surfaces 30i 'and 30i of the stator, a change takes place at least the inner surfaces of the stator 30, which can be seen from Figure 3a before insertion and after insertion of the sleeve part 10. The rough surface of the non-high-precision manufactured inner surfaces is leveled or even removed or displaced, wherein the soft material is changed on the surface, but at the same time applies mechanical forces for the spatial geometric fixation of the indented sleeves 10,11, which serve as bearing pieces.

The inner surfaces 11i, 10i of the two sleeves are high-precision, by insertion then also geometrically determined to meet their bearing function.

The outer surfaces 10a and 11a of the two sleeves make a mechanical connection with the inner surfaces 30i 'and 30i of the stator when the inserter 50 is pushed axially by pressure.

An alternative determination can be made by a hardening substance 12, if the inner surfaces 30i 'and / or 30i are made slightly larger in their spatial geometry, than the outer surfaces 11a and / or 10a of the sleeves 10 and / or 11, as Figure 6 illustrated. The insertion device then assumes the assignment of the eccentrically offset axes 100,101 of the two sleeves and placed them so long in the interior 31 with the two eccentric portions 30i, 30i 'of the stator 30 until an introduced hardening substance 12 fills the gap 13 fixing and the sleeves mechanically determined.

As a hardening substance, a solder or an adhesive can be used; the first hardens by lowering the temperature, the second by a chemical reaction.

The insertion once has the task to take over the mechanical assignment during the axial pressing. In the variant of the definition with a curable substance in the gap 13 (also as an irregular space), which has a size of between 20μm and 70μm, it assumes the geometric definition of the sleeves during curing, so it needs no additional mechanical when inserting in the direction s To apply force.

The second sleeve 11 is axially shorter and has an axial length L11. The entire stator length is L. After the stator 30 has the axial length L, the sum of the two sleeve lengths L11 and L10 is still shorter than the stator length. Of the Distance of the centers of the two sleeves is dL, which represents an axial offset, but with the end faces of the two sleeves 10,11 abut each other. This system of the two end faces will be explained with reference to FIG.

Figure 7 illustrates a top view in the axial direction 100,101 from above (seen from Figure 3 or Figure 6), the interiors R and W for the outer rotor and shaft are still open, so no wave 40 and no rotor 2 or 3 of the microsystem M used is. In this case, an end-face bearing surface 10b can be seen, which is also shown in FIG. 3 and in FIG. It has a width b, which is not constant circumferentially, which is due to the offset dr or Δr of the two axes 100,101, and also by the choice of the two diameters of the sleeves, here the outer diameter d10a of the longer sleeve 10 and the inner diameter d11i the shorter Sleeve 11. The diameter or the associated radii as respective half-diameter, as well as the radial offset (eccentricity) are chosen so that one of the hard bearing components 10,11 forms a lying outside the surface 10b annular axial support surface 10c, which also circumferentially entirely is continuous and on the other hard bearing component 11 rests.

Taking into account the radial offset dr, the outer diameter d10a of the sleeve 10 is greater than the inner diameter d11i of the sleeve 11, that at no circumferential point of the soft material of the stator 30 as part of the support surface 10b for the rotor 2 of Figure 1a and possibly also the inner rotor 3 of Figure 1a - viewed in the axial direction - comes to light or carrying. The rotor or rotors are then axially securely supported, inserted axially into the rotor space R, and have a good seal on the surface 10b, while the ring portion 10c, which supports the sleeves 10 and 11 to each other and aligns orthogonally, no longer visible from the outside.

The inner surfaces 11i and 10i form bearing surfaces for the shaft 40 and the outer rotor of the fluidic microcomponent M to serve as sliding bearings. The annular surfaces 10c and 10b together form the axially facing end face of the entire bearing component 10, which is provided for the shaft. The inner portion 10b is for supporting and aligning the microsystem, and the outer portion 10c lying around it on the same plane serves to align and support the second bearing member 11.

The plan view in FIG. 7 also illustrates the gap 13 from FIG. 6, which is already filled with an adhesive or a solder 12, around the gap Sleeve 11 set against the softer material of the stator 30. Before the solder or the adhesive cures, the sleeve 11 has been aligned with the outer annular surface 10c of the lower sleeve 10 by abutment, so that its axis 101 is aligned exactly parallel to the axis 100. The exact alignment results from a highly accurate production of the end faces, which run exactly perpendicular to the axes and thus can indirectly influence the positioning and positional accuracy. In one embodiment of specific dimensions, but not by way of limitation, the sleeve 10 was made to have an outer diameter of 5mm and an inner diameter of 1.2mm. The outer rotor 2 had an outer dimension of 3.8 mm and is thus - even taking into account the selected eccentricity of the two axes 100,101 within the outer dimension of 5.0 mm of him axially for providing a pivot bearing supporting sleeve 10. From this measure is also the inner dimension d11i see the second sleeve 11, according to the external dimension of the rotor to support him radially with a ring bearing in this respect. Both perpendicular to each other bearing, the inner wall surface 11i and the axially facing support surface of the sleeve 10 ensure accurate alignment and precise storage of the rotor component. 2

The gap 13 shown in Figure 7 in an excess for clarification results from the difference between the radius of the inner surface 30i 'of the stator 30, see Figure 3, and the outer dimension of the outer surface 11 a of the hard bearing sleeve 11. His measure is for a bond preferably between 50μm and 70μm, which would not be true to scale in the representation of Figure 7, if it had not been shown significantly enlarged.

FIG. 5 shows a perspective view when inserting the two bearing sleeves 10, 11, used in the case of an assembly and adjustment of the sleeves provided with an adhesive substance. The adhesive substance 12 is introduced into the gap 13, which is between 20 μm and 70 μm, based on the respective inner diameter of the stator 30 on the surfaces 30i and 30i '. The interior 31 for receiving the first sleeve 10 is longer than the bearing sleeve 10. The corresponding difference is - as shown in Figure 2 - from the radial shaft seal 24, which is set against the motor A through the spacer sleeve 21, taken. A Einsetzweg s of the two bearing sleeves 10,11, supported by the insertion device 50 of Figure 4 leads to the exact placement. After filling the adhesive substance 12, which may also be placed on the inner surfaces according to Figure 5 prior to insertion, the spatial geometric assignment and absolute placement of the sleeves 10,11 at least for a duration of curing the adhesive substance or the solder until the mechanical solidification occurs.

Also visible in Figure 5, the receptacle 22a, in which the positioning pin 22 of Figure 2 when placing the fluid guide portion 28,29,29 'engages. A stepped bore 22b radially offset therefrom, in each case on the inner side of the surface 30i 'and 30i of the stator 30, is predetermined. It circumferentially spaced from the receptacle 22a provides a way to use the fluid in a small amount after inserting and attaching the bearing sleeves 10,11 in the operation of the system M as a sliding bearing lubrication or in the ring flow. The bore 22b has a minimum depth L10 + L11. The stepped bore 22b, which can also be seen in FIG. 1a, lies with a portion of its bore depth in the surface region 30i '(cf., FIG. 3) and with a further portion in the surface region 30i. With it, the ring flow is achieved for the fluid flowing through the shaft bearing. Through the stepped bore a derivation of the located between the seal and shaft bearing fluid is achieved to the suction side of a microsystem, which is formed in this example as a pump. The fluid from the stepped bore 22b, which in this respect functions as a channel for the fluid, is taken up again in the fluid guide section 28, 29, 29 ', here in the microsystem facing section 29' by covering the channel and returned to the microsystem 2, 3.

It should be noted that the spatially geometrically highly accurate storage takes place only on one side, with respect to the shaft W but also a second bearing may be provided in the fluid guide member 29, but need not have such precision as the first storage in the sleeve 10, the also effective on an axially longer length L10.

The bearing parts can be made rotationally symmetrical simple as sleeves. You may also have a different outer diameter in the geometry, only its inner diameter and its inner surface must be aligned so that the rotors 40,2 (shafts and outer rotor of the microsystem) can be geometrically accurate and resistant to abrasion.

The described types of insertion and positioning can also be combined.

There may be a less strong mechanical connection when inserted by pressing in the sleeves 10, 11, determined by the corresponding adaptation of the Diameter geometries of inner and outer diameter of the sleeves. After the pressing process can be done via an additional device alignment and then bonding, so that both methods can also be used in combination.

The combined type of insertion can also take place in succession. The first receptacle with the inner surface 30i in the first section of the opening 31 of the stator can be connected to a mechanical press-in operation, in which the sleeve 10 is positioned exactly in position, as shown in FIG. 3a. With respect to the thus-defined first sleeve, which can then serve as an auxiliary bearing or an auxiliary device, the second bearing point (here with the sleeve 11) can be positioned in the section L11 with the arrangement according to FIG. 4, wherein a gap 13 shown in FIG Circumference between the outer surface 11a and the inner surface 30i 'filled with an adhesive substance 12. With a tight fit of the first sleeve 10, the second sleeve can be positioned and glued relative thereto and thus also relative to the stator. As an alternative to gluing, a pressing process can also take place during the second process, which corresponds to the variant described above, only in succession. The device according to FIG. 4 can be used for all these variants.

The combination of pressing and gluing has proven to be particularly accurate. First, the first sleeve 10 is pressed into the stator 30, wherein the two opening portions 30i, 30i 'are provided as two eccentrically arranged portions of the overall recess 31. After pressing in, the second bearing 11 is then formed, in which the highly accurately manufactured bearing sleeve is inserted into the housing, wherein it rests flat on the first sleeve, on the end face portion 10c. Subsequently, the position of the second sleeve relative to the first sleeve is defined, for which purpose the device according to FIG. 4 can be used. Subsequently, an adhesive 12 is allowed to enter the gap 13 on the outer surface 11a of the second sleeve and hardened to define this bearing point, that is to be firmly connected to the stator 30.

The squareness of the previous mechanical finishing of the sleeve 11 and the sleeve 10 can ensure that two auxiliary bearings help in positioning and fixing. An axial support surface 10c and the circumferential inner surface 10i, which indirectly via the device of Figure 4 can also influence the positional accuracy of the second inserted sleeve 11.

The two sleeves 10 and 11 can also be reversed in the order of attachment. First, the larger diameter sleeve 11, then - axially supported on the support surface portion 10c - the longer sleeve 10 for the shaft 40. The second sleeve 10 is then inserted from the clutch chamber 32 ago in the lower receiving portion of the recess 31.

It should be noted that the mechanically accurate positioning in terms of spatial geometric definition relates to two significant dimensions. Once the amount of the eccentricity vector "dr" as a radial offset. On the other hand, the correct absolute positioning of the two bearing sleeves 10,11 in the stator 30, so their position / location to the housing. This position is ensured by a pin which is inserted into the plate 51 of the device 50 of Figure 4 and engages in the housing instead of the pin 22a during assembly of the bearing sleeves 10,11. This pin is not shown in Figure 4, but it opens up from the context and the spatial / geometric arrangement of the receptacle 22a of Figure 2, in which the final assembly accepting pin 22 is located. It takes over the peripheral determination of the fluid guide portion 28,29,29 'relative to the housing 30, which is referred to as a stator.

Claims (14)

1. A microsystem for a fluid throughput, which microsystem has a first section for the inlet or outlet of fluid (F) and, in a second section, is provided with at least one bearing point (10, 11), wherein
   a rotor (40, 2) is rotationally mounted with respect to a stator (30) via at least one or two bearing bodies (10, 11), which bearing bodies are premanufactured from a hard material, characterised in that
   the stator (30), which comprises of a material which is softer than the one or two bearing body or bodies has one or two inner surface sections (30i, 30i') receiving the bearing body or bodies (10, 11).
2. A microsystem according to claim 1, wherein the two bearing bodies are arranged radially offset with respect to one another in the stator in such a way that the centre lines (100, 101) of the bearing bodies (10, 11) have a radial spacing from one another (dr).
3. A microsystem according to claim 1, comprising two axially offset (dL) but closely adjacent bearing points as separate bearing bodies (10, 11) in the stator (30).
4. A microsystem according to claim 1, wherein the stator (30) has a receiver (30i', 30i), as the inner section, initially not suitable for the at least one bearing body (10, 11).
5. A microsystem according to claim 4, wherein the initially not suitable inner section and the at least one bearing body (10, 11) form a gap with a size greater than zero during an insertion of the bearing body into the not suitable section and a hardening joining material is introduced into the gap (13) for fixing the bearing body relative to the stator after hardening of the joining material (12), especially as a solder or adhesive substance.
6. A microsystem according to claim 4, wherein the initially not suitable inner section is an underdimension of the receiver (30i', 30i) of the stator, into which a bearing body (10, 11), which is radially greater than the receiver, is pressed in mechanically, wherein the bearing body, which is harder with respect to the material, displaces a part of the receiving section of the stator (30), but at least changes it with respect to its surface structure.
7. A method for producing, adapting and/or adjusting at least one bearing point in a fluidic mini to microsystem (M), which system has a stator (30) and at least one rotor (40, 2), the rotor being rotatably mounted at the at least one bearing point (L10, L11) with respect to
   the stator, characterised in that the stator, prior to the insertion of at least one separate bearing body, has a section (30i, 30i') which is not suited for mounting, made of a softer material than the bearing body (10, 11); and in that
   the not suited section, by insertion, especially pressing in or bonding in, of the bearing body made of a material which is harder than the material of the stator, becomes a mechanical mounting and adjustment point, in order to fix the inner surface (11i, 10i) defined by the bearing body, highly precisely spatially/geometrically, as a bearing face for the rotational mounting of the rotor (40, 2).
8. A method according to claim 7, wherein the pressing in takes place with displacement, but at least with deformation of an inner surface (30i) of the not suited section.
9. A method according to claim 7 or claim 8, wherein a hardenable material (12) is introduced into a gap or, following the mechanical displacement, into remaining interstices, in order to obtain a mechanical fixing and spatial/geometric positioning of the bearing body as a bearing point after hardening of the filler (12).
10. A method according to any one of claims 7 to 9, wherein the bearing component (10, 11) has an external diameter of less than 15 mm, especially less than 10 mm and/or an internal diameter of less than 5 mm, especially less than 2 mm, for mounting the outer rotor (2) especially a shaft (40).
11. A method according to claim 7, wherein two bearing points (L10, L11), are fixed successively with respect to time, one by pressing in (10a, 10i) and a further one by soldering, bonding in (11a, 11i) or pressing in.
12. A method according to claim 11, wherein, firstly, pressing in and then bonding in take place.
13. A method according to claim 11 or claim 12, wherein the pressed-in first bearing point is used as an auxiliary bearing point which is fixed relative to the stator (30), in order to position the second bearing point (L11) spatially/geometrically, before it is fixed by the hardening material (12).
14. A method according to claim 11 or claim 13, wherein the second bearing point (11; 11a, 11i) is positioned in the axial (10b) and/or radial (10i, 11i) direction, supported from the first bearing point (10).

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