DE102017108792A1 - Working head with two axes of rotation - Google Patents

Abstract

Disclosed is a working head having two axes of rotation for a five controlled axis machining center wherein a first axis of rotation is rotated by a radial flux motor and a second axis of rotation is rotated by an axial flux motor comprising a rotor ring carrying permanent magnets and between two stator rings which carry the electrical windings, wherein the rotor ring is fixedly connected to an electrospindle assembly.

Description

Background of the invention

The invention relates to a working head with two axes of rotation, in particular a working head comprising at least one electric spindle, for example, for various machining processes (milling, drilling, cutting, flanging, profiling, turning, polishing, etc.) of objects made of any workable material (For example, wood, wood materials, resins, composites, aluminum, PVC, steel, light alloys, etc.) is suitable.

In particular, but not exclusively, the invention may usefully be used in the field of a numerical control machining center, particularly in a five controlled axis machining center, in which a working head with two axes of rotation contains the two axes of rotation of the machine carrying the electric spindle.

The prior art includes the publication of the patent WO 2009/034030 , which describes a working head with two axes of rotation and with a fork which rotates about a first axis, an electric spindle which lies between the two arms of the fork and which rotates about a second axis, a first electric motor with direct drive for the rotation the fork about the first axis, two second direct drive electric motors for rotating the electric spindle about the second axis, the rotor of the first motor being flanged directly to the fork, and the stator of each of the second motors being housed in a housing attached to the outsides of the fork.

The prior art is in need of improvement in view of some aspects. First, it is desirable to provide a working head with two axes of rotation in a relatively small size. It is also desirable to increase the efficiency of the drives for the working head with two axes of rotation. Another aspect that should be improved is the simplicity of the construction of the working head.

Summary of the invention

One purpose of the invention is to overcome one or more of the above limitations and disadvantages of the prior art.

One advantage is that a working head with two axes of rotation is created in relatively small dimensions.

One advantage is that a working head with two axes of rotation, which are provided with relatively high efficiency drives, is equipped.

One advantage is that a working head with two axes of rotation, which are relatively simple constructed, is produced.

One advantage is that it creates a working head suitable for a five-axis machining center.

These purposes and advantages and others are all achieved with the working head according to one or more of the claims listed below.

In one example, a working head having two axes of rotation includes a first axis of rotation that is rotated by a radial flux motor and a second axis of rotation that is rotated by an axial flux motor that includes at least one rotor ring that carries permanent magnets and is sandwiched between two stator rings carrying the electromagnetic coils, the rotor ring being fixedly connected to an electrospindle assembly.

Brief description of the drawings

The invention may be better understood and appreciated with reference to the accompanying drawings, which illustrate some examples without limitation of the applications.

The Figure 11 is an elevational view of an example of a working head made in accordance with the present invention.

The shows a side view of the working head ,

shows the cross section III-III of ,

The shows a cross section of a torque motor, which acts as a direct drive for the second axis (axis A) of the working head is used.

shows an outline of the engine in cross section.

The shows a cross section of a torque motor, the direct drive for the first axis (axis C) of the working head on is used.

The shows a cross section of another example of a torque motor, as direct drive for at least one axis of the working head is used.

Detailed description

With reference to the above pictures was with 1 a working head for a numerically controlled machining center (not shown) in its entirety, in particular a working head for machining workpieces made of wood, wood-based materials, aluminum, plastics, composites, etc. The numerically controlled machining center can, for example, a center with five controlled machining axes X, Y, Z, C, A, wherein the three axes X, Y, Z are assigned to the part of the machining center which is the working head 1 holds, while the other two (rotary) axes C and A the working head 1 are assigned.

The working head 1 can in particular holding means 2 include, which are intended for mounting on a moving part (not shown) of the machining center. This movable part may offer the possibility of controlled movement along the three (orthogonal) axes X, Y, Z. The retaining means 2 may comprise, as in this case, at least one housing with attachment means for the (detachable) connection to the moving part of the machining center.

The working head 1 in particular, a holder 3 comprising an electrospindle assembly 4 wearing. The electrospindle holder 3 may in turn be from holding means 2 being held. The holder 3 can with respect to their position to the support means 2 be adjustable to at least a first axis of rotation C.

As I said, the working head 1 an electrospindle tool carrier assembly 4 include that of an electrospindle holder 3 will be carried. The electrospindle tool carrier assembly 4 may in particular comprise a spindle axis for rotation of the tool carrier spindle. The spindle axis can be at least by the regulation about the first axis of rotation C and / or about a second axis of rotation A, which is transverse to the first axis of rotation C, pivotable.

The retaining means 2 can first drive means (for example, a first electric motor 5 include) which are mounted to regulate the electrospindle holder 3 can drive about the first axis of rotation C. The electrospindle holder 3 can second drive means (for example, a second electric motor 6 comprise) for driving the rotation of the electrospindle assembly 4 wear around the second axis of rotation A.

The second drive means (second motor 6 or motor axis A) may in particular comprise a torque motor. As is known, a torque motor (torque motor) usually comprises a special brushless synchronous motor with permanent magnets (with direct drive). The second drive means (second motor 6 or motor axis A) can in particular stator means 7 include (fixed) with the electrospindle holder 3 are connected. The statuary means 7 can do so on the bracket 3 be appropriate that they are together with the bracket 3 turn around the first axis C.

The second drive means (second motor 6 or motor axis A) can in particular rotor means 8th include (fixed) with the electrospindle assembly 4 are connected. The rotor means 8th can do so on the electrospindle assembly 4 be appropriate that they are together with the electrospindle assembly 4 turn around the second axis A. The rotor means 8th In particular, at least one rotor lying coaxially to a second axis A may comprise (fixedly) with the electrospindle assembly 4 connected is.

The second drive means (drive axis A) can in particular electromagnetic winding means 9 include, on the Statements 7 attached (mounted) are. The second drive means (drive axis A) can in particular permanent magnet means 10 include that on the rotor means 8th attached (mounted) are.

The statuary means 7 and the rotor means 8th can like on the . . and be configured so that the magnetic flux substantially in a direction parallel to the second axis A extending direction (axial flow) flows from one to the other.

The statuary means 7 in particular, at least one first stator ring 11 include the (fixed) with the bracket 3 connected is. The electromagnetic winding means 9 like in the example on the - Windings include those on the first stator ring 11 are attached.

The rotor means 8th can a slice 12 comprise, in turn, at least a first, the first stator ring 11 facing side includes. The permanent magnet means 10 In particular, at least one first array of magnets may be on the first side of the disk 12 include.

The statuary means 7 In particular, as in the example on the - at least one second stator ring 13 include (fixed) with the bracket 3 connected is. The second stator ring 13 can from the first stator ring 11 be spaced in a direction parallel to the second axis A extending direction. The electromagnetic winding means 9 may include windings on the second stator ring 13 are attached.

The disc 12 can, as in this example, between the first stator ring 11 and the second stator ring 13 to be appropriate. The disc 12 in particular, at least one second, the second stator ring 13 facing side. The second side of the disc 12 may be on the opposite side of the first page.

The permanent magnet means 10 In particular, at least one second array of magnets may be on the second side of the disc 12 include.

The statuary means 7 For example, as in these examples, they may comprise at least one annular, for example substantially toroidal, stator element (for example of rectangular cross-section). On at least one side of the stator element, one or more grooves for receiving the electromagnetic winding means can be achieved. The grooves can be arranged radially. The grooves can be slightly inclined to reduce the cogging torque.

The permanent magnet means 10 may in particular comprise a plurality of (magnetized in the axial direction) permanent magnets which are in grooves on the two opposite sides of the (for example made of non-magnetic material) disc 12 are housed and on both sides of the disc 12 protrude.

The working head 1 can in particular angle position sensor (for example, an encoder) for detecting at least one angular position of the rotor means 8th include. The working head 1 In particular, it may include programmable electronic control means equipped with computer program instructions and configured to control the position of the second axis A based on at least one signal output by the angular position sensors.

The first drive means (first motor 5 or motor axis C) may in particular comprise a second torque motor. The first drive means (first motor 5 or motor axis C) can in particular second stator means 14 Include (fixed) with the brackets 2 are connected. The first drive means (first motor 5 or motor axis C) can in particular second rotor means 15 Include (fixed) with the bracket 3 are connected.

The first drive means (drive axis C) can in particular second electromagnetic winding means 16 include, on the second stator means 14 are attached. The first drive means (drive axis C) can in particular second permanent magnet means 17 comprise, on the second rotor means 15 are attached. The second rotor means 15 In particular, at least one rotor coaxial with a first axis C may comprise. The second stator means 14 For example, an annular, with respect to the second rotor means 15 external part. In particular, the annular external part may be coaxial with the second rotor means 15 be. The second stator means 14 can be configured and with regard to the second rotor means 15 be arranged so that the magnetic flux substantially in the radial direction with respect to the first axis C flows from one to the other (radial flow).

The electrospindle assembly 4 can without the use of transfer agents directly with the rotor means 8th of the second engine 6 (Motor axis A) to be connected. Therefore, the second axis A is controlled with a direct drive.

The second drive means (drive the second axis A) can for the rotatable coupling of the second axis A with the holder 3 be connected with roll-holding means (rolling bearings).

The second drive means (second axis drive A) may be operatively connected to the sensor means (encoders) used to feedback control the angular position of the second axis A.

In the example on the - comprise the second drive means (second motor 6 or Drive Axis A) a multi-stage axial flux motor, which in this case has two stator elements (the first and the second stator ring 11 and 13 comprise) and a rotor element (which the disc 12 includes). The use of several stator and / or rotor elements makes it possible to increase the effective area for torque generation (increasing the torque density) with the same volume. In other words, the structure with two stator elements (with the same diameter) can achieve two effective areas for generating torque, which leads to a corresponding increase in the torque density.

On An example of a single-stage axial flow motor (only one stator element and one rotor element) can be seen, which can be used in non-illustrated examples as a first torque motor (drive C axis) and / or as a second torque motor (drive axis A). In other examples, not shown, one can Axialflussmotor with two stator elements, in particular as in the example on the - used as the second torque motor (drive A), as the first torque motor (drive C axis). In other examples, not shown, a radial flux motor, in particular as on the as in the example on the - used as the first torque motor (drive C axis), as a second torque motor (drive axis A).

As in other examples, not shown, all possible combinations of various torque motors (radial flux motor, single-stage axial flow motor, multi-stage axial flow motor, etc.) can be used as the first torque motor (drive C axis) and as the second torque motor (drive A axis).

The permanent magnet means of the examples cited in this specification may comprise magnets which are coated with an electrically insulating material (in particular ferromagnetic material, for example ferrite) to protect the magnets from the danger of possible demagnetization, for example in field weakening operations. The coating of the magnets (for example with ferromagnetic material) allows effective field weakening of the motor with existing demagnetizing stator currents since alternative paths are provided for the flux generated by the magnets.

The torque motors described herein may include coolant (eg, liquid coolant).

The axis (second axis A), directly the electrospindle assembly 4 carries is driven (with direct drive) via a torque motor, in particular a Axialflussmotor, in particular a multi-stage Axialflussmotor (for example, comprises a rotor element between the two stator elements). This construction, with which an effective drive of the electrospindle assembly 4 is possible (for cutting material processing), is housed in an appropriate space, which is available in the context of a working head with two axes of rotation.

The direct drive also allows a high dynamic response to the rotation regulation of the electrospindle assembly (about axis C and / or about axis A), avoiding hysteresis due to backlash and yield of a possible mechanical transmission system. By using at least one three-phase motor, moreover, the rotational speed of the electrospindle assembly can be uniformly and regularly modulated.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2009/034030 [0003]

Claims (9)

Working head ( 1 ) with two controlled axes (C; A), comprising: - a holder rotatable about a first axis (C) (C) 3 ); - a first engine ( 5 ) as a drive for the rotation of the holder ( 3 ) about the first axis (C); An electrospindle assembly ( 4 ) coming from the bracket ( 3 ) and is rotatable about a second axis (A); A second motor ( 6 ) as a drive for the rotation of the electrospindle assembly ( 4 ) about the second axis (A); the second motor ( 6 ) a torque motor with stator means ( 7 ), Rotor agents ( 8th ), electromagnetic winding means ( 9 ), which are based on the 7 ), and permanent magnet means ( 19 ) on the rotor means ( 8th ), the stator means ( 7 ) with the bracket ( 3 ) and the rotor means ( 8th ) with the electrospindle assembly ( 4 ) are connected. Working head according to claim 1, wherein the stator means ( 7 ) on the bracket ( 3 ) are mounted or fastened and / or wherein the rotor means ( 8th ) on the electrospindle assembly ( 4 ) are mounted or attached. Working head according to claim 1 or 2, wherein the stator means ( 7 ) and the rotor means ( 8th ) are configured such that the magnetic flux substantially flows in a direction parallel to the second axis (A) from one to the other. Working head according to any of the above claims, wherein: - the stator means ( 7 ) at least one first stator ring ( 11 ) connected to the holder ( 3 ) connected is; The electromagnetic winding means ( 9 ) comprise at least first winding means, which on the first stator ring ( 11 ) are attached; - the rotor means ( 8th ) a disk ( 12 ) comprising at least a first, the first stator ring ( 11 ) facing side comprises. The permanent magnet means ( 10 ) at least a first arrangement of magnets on the first side of the disc ( 12 ). Working head according to claim 4, wherein: - the stator means ( 7 ) at least one second stator ring ( 13 ) connected to the holder ( 3 ) and from the first stator ring ( 11 ) is spaced in a direction parallel to the second axis (A) extending direction. The electromagnetic winding means ( 9 ) comprise at least second winding means, which on the second stator ring ( 13 ) are attached; - the disc ( 12 ) between the first stator ring ( 11 ) and the second stator ring ( 13 ) and at least one second side, which is opposite to the first side and the second stator ring ( 13 ) is facing. The permanent magnet means ( 10 ) at least a second arrangement of magnets on the second side of the disc ( 12 ). Working head according to any one of the preceding claims, wherein the first motor ( 5 ) comprises a second torque motor, the second stator means ( 14 ), second rotor means ( 15 ), second electromagnetic, on the second stator means ( 14 ) mounted winding means ( 16 ) and second, on the second rotor means ( 15 ) mounted permanent magnet means ( 17 ), wherein the second rotor means ( 15 ) with the bracket ( 3 ) and comprise a coaxial with the first axis (C) lying rotor. Working head according to claim 6, wherein the second stator means ( 14 ) comprise at least one annular external part which is coaxial with the second rotor means ( 15 ) so that the magnetic flux flows substantially radially with respect to the first axis (C) from one to the other. Working head according to any one of the preceding claims, wherein the rotor means ( 8th ) comprise a rotor coaxial with the second axis (A). A working head according to claim 8, comprising angular position sensors for determining the angular position of the rotor and programmable electronic control means equipped with computer program instructions and configured to control the position of the second axis (A) based on at least one signal output by the angular position sensors.

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