WO2006094967A1

WO2006094967A1 - Large-surface secondary part of a direct drive and process for producing the same

Info

Publication number: WO2006094967A1
Application number: PCT/EP2006/060498
Authority: WO
Inventors: Jürgen Weyh; Wolfgang Heinrich; Martin Hotop
Original assignee: Ina Drives & Mechatronics Gmbh & Co. Ohg
Priority date: 2005-03-08
Filing date: 2006-03-06
Publication date: 2006-09-14
Also published as: DE102005011067A1

Abstract

A process is disclosed for producing a secondary part of a direct drive. According to the invention, once a support (4) is produced, a homogeneous layer (6) of a permanently magnetisable material is applied and forms, at least after its application step is concluded, a solid surface as running surface (3) for a primary part (1) of the direct drive. This homogeneous layer is then magnetised section by section so as to form numerous magnetic poles in the running direction of the primary part. Also disclosed is a secondary part (2) of a direct drive in which the running surface (3) comprises an integrally formed, permanently magnetised material layer (6).

Description

Large area secondary part of a direct drive and method for its production

The present invention relates to a large-scale ^secondary part of a direct drive and a suitable method for its preparation.

Direct drives in the sense of the present invention are understood to mean various motors which are characterized in that a primary part, in which electrical coils are provided for generating an electromagnetic field, interacts with a secondary part, which in turn has an air gap surface (running surface) for the primary part provides. The secondary part has numerous magnetic poles, the alignment of which alternates in the direction of travel. Such direct drives can be designed, for example, as linear motors or planar motors. In principle, it does not matter whether the direct drive works or not

The primary part or the secondary part are built to be fixed to the frame. In many applications, particularly when large motion ^¬ stretch are required, but the secondary part is fixed to the machine frame and the primary part is moved without contact via the air gap area.

In special embodiments of direct drives, the secondary part can be cylindrical or prism-shaped, wherein the running surface can be provided both on the outer and on the inner surface of a hollow cylinder or hollow prism. With these designs, rotary or linear movements can be generated. For producing high drive forces the tread Derar ^¬ term direct drives is composed of numerous permanent magnets. Such permanent magnets are usually made from special sintered materials and subjected to a magnetization process. In the magnetized state, the permanent magnets are attached to a carrier of the secondary part. This production method requires precise assembly ^¬ devices and has a substantial increase in costs.

The object of the present invention is therefore to provide an improved secondary part of a direct drive, in which the assembly costs can be drastically reduced, particularly in the case of large running surfaces. Furthermore, the invention is intended to provide a method for producing such a large-area secondary part.

According to the invention, the object is achieved by applying a homogeneous layer of permanently magnetizable material to a large-area support to be produced beforehand, which layer provides a solid surface as a running surface after the application step has been completed. After this homogeneous layer has been produced, the homogeneous material layer is magnetized in sections, so that numerous alternating magnetic poles are formed in the running direction of the secondary part. The running surface of the secondary part produced in this way is thus formed in one piece.

A major advantage is that the magnetic tread can be produced in a few automated manufacturing steps. The time-consuming positioning and fastening of numerous individual permanent magnets on the No carrier material. In addition, high precisions can the position of the individual poles are also achieved through large stretches respect by the nachträg ^¬ Liche magnetisation of the individual magnetic poles.

It is advantageous if the magnetizable material layer is produced from a sinter powder and is formed in a surface recess in the carrier. During the development herstel ^¬ a powdery or pasty mass can be introduced into this recess and harden there with corresponding process steps. For example, the sinter powder can be mixed with a synthetic resin, which provides a permanently stable running surface after curing.

In order to compensate for different coefficients of thermal expansion, it is expedient to form expansion joints between the magnetizable material layer and the carrier. These expansion joints can be filled with a permanently elastic mass. In addition, it can be advantageous to couple the magnetizable material layer to the carrier via a permanently elastic connecting layer, so that a slight displacement of the magnetized material layer remains permanently possible. In this way, the impulses that occur during operation of the direct drive can be partially compensated, thereby increasing the smoothness of operation. With large driving forces, the tread shifts slightly and in this way absorbs some of the unwanted impulses that would otherwise be transmitted completely to the machine ^frame . The rigidity of the machine frame can thus be designed to be lower. -A-

A preferred embodiment of the secondary part comprises at least one material measure wei ^¬ terhin, via which the position of the primary part of the direct drive with the aid ent ^¬ speaking sensors can be determined. The Material measure can advantageously also made numerous magnetic ^¬-Nazi Poland exist that are formed in the magnetic material layer. In order to increase the measuring accuracy, the step size of these measuring poles will usually be significantly smaller than the step size of the poles formed in the running surface. Of course, other material measures can also be used, for example a glass scale attached to the carrier.

Further advantages, details and further developments result from the following description of preferred embodiments of the invention, with reference to the drawings. Show it:

Fig. 1 is a simplified perspective view of a

Direct drive with a first embodiment of a secondary part according to the invention;

Fig. 2 is a simplified cross-sectional view through a second embodiment of the invention

Secondary part;

Fig. 3 is a plan view of a third embodiment of the

Secondary part with a material measure;

Fig. 4 is a simplified perspective view of a fourth embodiment of the secondary part, which is cylindrical. Fig. 1 shows a simplified perspective view of a direct drive. The direct drive comprises a ^primary part and a secondary part 1 2, which provides a surface 3 for the primary part. The primary part 1 contains elec tric ^¬ drive coils (not shown), the flow at current generating an electromagnetic field to the drive ^¬ forces to provide. The primary part 1 is supplied with energy via cable feeds which have not been shown in FIG. 1. The storage of the primary part is not shown for reasons of simplification.

The secondary part 2 has a support 4 which can be secured over Fixed To ^¬ supply elements 5 on a machine frame. In modified embodiments, but also the primary part could be designed stationary while the ^secondary part 2 is movable. To produce the secondary part, a homogeneous layer 6 made of magnetizable material is produced on the carrier 4. The homogeneous layer 6 is then located in one piece on the support 4. The layer 6 is at ^¬ play, of a mixture of magnetizable sintered powder and synthetic resin. Such a material layer could be applied to the carrier 4 in a pasty state, in order to then be combined there under increased pressure and / or elevated temperature and / or UV light radiation

To be subjected to curing step. However, it is also conceivable for the homogeneous layer 6 to be produced outside the carrier 4 and to be glued thereon as a film or otherwise connected to the carrier.

In the subsequent process step, the homogeneous layer 6 is permanently magnetized by impressing appropriate magnetic fields. Magnetization takes place in sections, so that numerous magnetic poles are formed in the homogeneous layer 6 along the desired running direction for the primary part 1. For this, a entspre ^¬ accordingly dimensioned magnetizing coil is for example performed gradually over the layer. 6 In contrast, the material of the carrier 4 should preferably be selected so that no permanent magnetization takes place. The carrier may ^¬ example, consist of soft iron or other ferromagnetic or paramagnetic materials to provide for the poles of the magnetic yoke layer 6 ready.

After completion of the secondary part, the layer 6 is wei ^¬ terhin one piece, but with varying according to the poles formed magnetic properties and field strengths inside the layer. Among other things, this offers the advantage that there are no gaps between the individual poles on the tread 3, which is formed on the top of the homogeneous layer 6, in which dirt could be deposited. For further surface treatment, the tread 3 can be used before or after magnetizing the homogeneous

Layer 6 ground, polished or otherwise finished ^¬ the. If, for example, an air bearing is to be built up between primary part 1 and running surface 3 during operation, a high level of planarity of the running surface is required. Mechanical protection of the tread 3 different non-magnetic outer layers may serve as the ver from Sinterpul ^¬ homogeneous layer produced exhibits 6 often only comparatively ^¬ as low surface hardness. A DLC layer (Diamond-Like Carbon), for example, is particularly advantageous because it shows a very high hardness with the smallest thickness. 2 shows a cross-sectional view of a detail of a modified embodiment of the secondary part. In this case, the carrier 4 has a trough-like surface recess 8 in which the homogeneous layer 6 is embedded. Between the homogeneous layer 6 and the

In this embodiment, the bottom of the surface recess 8 has a connecting layer 9, by means of which the homogeneous layer 6 is attached to the carrier 4. When Ver ^¬ bonding layer 9 may be layer is a permanently elastic adhesive, which allows to a certain extent relative movements between the homogeneous layer 6 and the support. 4 Thus for example different tempe ^¬ duced length changes can be compensated. So that it does not come in these cases to undesirable material stresses, further between the support 4 and the homogeneous layer 6 is hen 10 vorgese ^¬ at the side edges, an expansion joint, into which elastic material is filled joints. This joint material should preferably be non-magnetic in order to avoid an undesired magnetic flux between adjacent magnetic poles of the layer 6. In this context, it is also understandable that the expansion joint also brings about a magnetic separation between the side edges of the poles and the carrier 4, which is in any case expedient if the carrier consists of a magnetically conductive material.

In order to allow rapid removal of the heat generated in the layer 6 in the case of high power requirements, 4 heat-conducting elements 11 can be arranged in the carrier, in which, for example, a coolant is guided. In addition, it is conceivable that the carrier 4 has a certain profile in order to increase the bending stiffness. It is also conceivable to use the material of the homogeneous layer 6 and / or To provide connecting layer 9 with suitable additives which allow the coefficients of thermal expansion to be adapted to the material of the carrier 4 and / or ensure good heat transport.

Fig. 3 shows a third embodiment of the secondary part in a view from above. In turn, the homogeneous layer 6 is embedded in the carrier 4, in which numerous adjacent magnetic poles are formed. The running direction of the primary part, not shown in this embodiment, is shown by a double arrow. So that the position of the primary part can be determined, a first material measure 12 is arranged on the secondary part, which is designed, for example, as a glass scale and is attached to the carrier 4.

Simultaneously or alternatively, a second material measure 13 can be produced as a component of the homogeneous layer 6. If a magnetic sensor is arranged on the primary part, the second material measure 13 is also formed as a sequence of alternating magnetic poles. To increase the measuring accuracy, the pole pitch in the second material measure 13 is selected to be significantly smaller than in the homogeneous layer 6, as is symbolized by the dashed lines. In order to prevent excessive magnetic interference between the poles of the running surface 3 and the poles of the second material measure 13, a groove 14 can be introduced between these two sections of the homogeneous layer 6 and filled with a filler material. As was also indicated by dashed lines in the right section of the homogeneous layer 6, magnetic poles or field lines extending obliquely to the running direction can also be formed if this appears expedient to improve the running properties of the primary part. This is another important advantage of the secondary part according to the invention. Since the homogeneous layer 6 is magnetized only at a late stage in the manufacturing process of ren ^¬, can produce different effective magnetic secondary parts with the same mechanical components. It is even possible to change the pole directions or field strengths in the homogeneous layer 6 in different sections of the same secondary part, in order thereby to provide special solutions for direct drives.

If the homogeneous layer 6 is rigid in itself, but is connected to the carrier 4 by means of a permanently elastic connecting layer, the expansion joints 10 permit slight relative movements between the homogeneous layer 6 and the carrier 4. This can be used for effective pulse ^decoupling . Due to the impressed driving forces the tread of the secondary part is moved low ^¬ fügig while acting on the support 4 only decreased impulses. In this way there is an effective decoupling from the machine frame, so that unwanted vibrations and running noise are reduced.

A fourth embodiment of the secondary part is shown in FIG. 4 to illustrate the various possibilities of using the present invention. In this case the secondary component is in the form of a hollow cylinder, wherein the homogeneous layer 6 is applied on the outside of the gene zylinderförmi ^¬ carrier. 4 Especially when building Rota- tion engines, which use the principle of the direct drive, the relatively free design brings the course of magneti ^¬ rule poles in the layer 6 many advantages. The inside of the carrier 4 can be used for guidance purposes.

Changing geometries of the support and the course of the magnetic poles ^¬ tables are conceivable. For example, the carrier can be prism-shaped.

Reference symbol list

1 - primary part

2 - secondary part

3 - tread

4 - straps

5 - fasteners 6 - homogeneous layer

8 - surface recess

9 - connection layer 10 - expansion joint 11 - heat conducting elements

12 - first measuring standard

13 - second measuring standard

14 - groove

Claims

1. A method for producing a secondary part (2)

Direct drive, comprising the following steps: - providing a carrier (4);

- Applying a homogeneous layer (6) made of permanently magnetizable material, which provides a solid surface as a running surface (3) for a primary part (1) of the direct drive at least after the application step has been completed;

- are formed so that (1) number ^¬ rich magnetic poles in the running direction of the primary part portion-wise magnetisation of the homogeneous layer (6).

2. The method according to claim 1, characterized in that the homogeneous layer (6) is applied in one piece to the entire running surface (3) of the secondary part (2).

3. The method according to claim 1 or 2, characterized in that the tread (3) before or after the application of the homogeneous layer (6) is divided into several tread sections.

4. The method according to any one of claims 1 to 3, characterized in that the homogeneous layer (6) comprises a sintered ^¬ powder which is sintered onto the support (4).

5. The method according to any one of claims 1 to 4, characterized in that the homogeneous layer (6) selbsttra ^¬ constricting properties and that the support (4) after curing of the magnetizable layer (6) is removed again.

6. The method according to any one of claims 1 to 5, characterized in that a Oberflächenaus ^¬ saving is introduced (8) in the support (4), which extends in the region of the tread (3) and in which the magnetizable material for applying the homogeneous layer (6) is filled.

7. The method according to claim 6, characterized in that expansion joints (10) are introduced on the side edges between the carrier (4) and the magnetizable material (6).

8. The method according to claim 7, characterized in that an elastic non-magnetic ^¬ joint material is introduced into the expansion joints (10).

9. The method according to any one of claims 1 to 8, characterized in that the homogeneous layer (6) is ground and / or polished at least in the region of the tread (3) before or after magnetization.

10. The method according to any one of claims 1 to 9, characterized in that the homogeneous layer (6) before or after the magnetization is coated at least in the region of the tread (3) with a surface coating, in particular a hard carbon layer.

11 secondary part has a direct drive with a carrier (4) and a tread (3), the numerous, alternating in the direction of magnetic poles labeled in characterized ^¬ characterized in that the running surface (3) consists of an integral, permanently magnetized material layer (6) consists.

12. Abutment according to claim 11, characterized is that the magnetised material layer (6) in an upper surface recess ^¬ (8) incorporated in the support (4).

13. Secondary part according to claim 12, characterized in that at least in the running direction between the carrier

(4) and the magnetic material layer (6) ^¬ strain joints (10) are introduced.

14. Secondary part according to one of claims 11 to 13, characterized in that between the carrier (4) and the magnetized material layer (6) a connection ^¬ layer (9) is arranged, which consists in particular of a permanently elastic adhesive material.

15. Abutment according to one of claims 11 to 14, characterized in that the magnetic flux lines in the magnetic ^¬ tables poles of the tread (3) extending perpendicular or at an angle to the running direction of the primary part (1) of the direct drive.

16. Secondary part according to one of claims 11 to 15, characterized in that the carrier (4) consists of a magnetically conductive material and provides the magnetic inference for the poles of the tread (3).

17. Secondary part according to one of claims 11 to 16, characterized in that a material measure (12, 13) is also provided, via which the position of the primary part (1) can be determined by a sensor attached to the primary part (1) of the direct drive.

18. Abutment according to claim 17, characterized in that the measuring scale (13) alternately formed magnetic Maßpole is formed in the magnetized layer of material (6) in the running direction old ^¬, wherein the pitch of the Maßpole significantly smaller than the step width of the tread (3) forming poles.

19. Secondary part according to one of claims 11 to 18, characterized in that the tread (3) along the direction of ^{travel ¬} against a restoring force against the carrier (4) is displaceable.

20, abutment after to claim 17 or 18 back claim related ^¬ NEN claim 19, characterized in that a first measuring scale (12) is fixed immovably on the support (4), and that a second measuring scale (13) fixedly connected to the tread (3) wherein the second measuring scale (13) is used for correction of the commutation is connected to the surface by the displacement of the running ^¬ (3) occurs relative to the carrier (4).

21. Secondary part according to one of claims 11 to 20, characterized in that the tread (3) was produced by a method according to one of claims 1 to 10.