WO2012136645A1

WO2012136645A1 - Optical rotary transmitter and method and apparatus for the production thereof

Info

Publication number: WO2012136645A1
Application number: PCT/EP2012/056049
Authority: WO
Inventors: Stephan Ott; Robert RAUM; Harry Schilling; Matthias Rank
Original assignee: GAT Gesellschaft für Antriebstechnik mbH
Priority date: 2011-04-04
Filing date: 2012-04-03
Publication date: 2012-10-11
Also published as: DE112012001561A5

Abstract

The present invention relates to an optical rotary transmitter for directly transmitting an optical signal between a stationary and a rotating machine part, having a rotor (10), which has a bearing portion (15) with a first bearing seat (17) defining a first bearing axis (16), wherein a first optical component (13) having a first optical axis (14) is received in a first hole in the rotor, and having a stator (20), which has a second bearing portion (25) with a second bearing seat (27) defining a second bearing axis (26), wherein an optical component (23) with a second optical axis (24) is arranged in a second central hole (21) in the stator (20), wherein a sleeve of the optical component or the first hole receiving the sleeve with a good fit defines a first axis (12) which does not coincide with the first optical axis, and wherein the first and second optical axes are aligned with the rotation axis of the rotor. In order to provide an optical rotary transmitter with the features mentioned at the outset and to provide a corresponding apparatus and a method for the production thereof, which make it possible to drastically reduce the error tolerances for the alignment of the optical axis relative to the rotation axis of the transmitter and render them considerably more stable in the long term, the invention proposes that the contact faces of the rotor, which determine the position and orientation of the optical axis, are processed outside the first hole such that the first axis (12) is misaligned relative to the first bearing axis (16) while the first optical axis (14) coincides with the first bearing axis (16).

Description

Optical rotary transformer and method and apparatus for its production

The present invention relates to an optical rotary transformer for the direct transmission of an optical signal between a stationary and a rotating machine part, comprising a rotor having a central first bore and a first optical component received therein with a first optical axis and a first bearing seat a first bearing axis defined, and having a stator having a second central bore and an optical component received therein with a second optical axis and a second bearing seat defining a second bearing axis, wherein a sleeve of the component or the sleeve fitting receiving first bore in the rotor defines a first axis that does not coincide with the first optical axis, and wherein the first and second optical axes are aligned with the axis of rotation of the rotor.

Likewise, the present invention also relates to a corresponding method for producing and adjusting a rotary optical transformer of the aforementioned type.

Corresponding optical rotary joints are required when optical signals are directly, i. without intermediate conversion into electrical signals, to be transmitted contactlessly from a stationary to a rotating element, wherein both elements can also be rotatable around the common axis in space. In particular, this involves contactless optical data transmission from a stationary to a rotating machine part or vice versa.

For a corresponding non-contact optical data transmission optical components are often used, which could also be referred to as (optical) "signal element" or "optical transmission element, and which typically consist of an elongated cylindrical sleeve, in which opens and ends of an optical fiber fixed substantially coaxially with the sleeve, optical signals emerging from the free end of this optical fiber and collimated by an imaging optic provided at the other end of the sleeve, for example a collimator lens, to converge on the opposite end Part in a similar manner and vice versa coupled back into an optical fiber too become. Optionally, the collimated by the collimator optical signal can also be redirected by a deflection mirror.

Of course, one tries to such components, d. H . However, in practice it turns out that the bundled light beam emanating from the collimator lens does not coincide exactly with the axis of the sleeve, which in turn typically coincides with the production of the units consisting of an optical fiber, a sleeve and a collimator lens is arranged in a matching bore whose axis is also referred to here as "first axis". The first axis is therefore at the same time the geometric axis of the sleeve or the sleeve receiving this bore. The light beam emerging from the signal or the optical axis defined by the light beam is accordingly opposite the axis of the bore or the outer cylindrical sleeve, here referred to as "first axis", wherein the sleeve and the bore also have a square or other polygonal cross section However, they could in any case define a first axis, more or less offset and tilted. The optical axis thus does not run along the first axis of the bore of the receiving element receiving the component (with random exceptions).

To compensate for this, in some rotors or rotary bearings according to the prior art, a larger bore or a larger cavity for receiving the collimator sleeve is provided, which ensures sufficient clearance for the collimator sleeve, so that it can initially with the aid of a suitable device is adjusted to the cavity so that the axis of rotation of the rotor (which coincides generally with the axis of the sleeve-receiving cavity) coincides with the optical axis of the collimator. In this adjusted and provisionally fixed position, the remaining cavity is then filled with a filling material or adhesive and the collimator sleeve is glued and fixed in the cavity of the rotor or rotary bearing.

However, this method is too inaccurate for demanding applications, since the necessarily thick, relatively thick filler or adhesive layer is distributed asymmetrically around the sleeve after the corresponding adjustment, so that due to external influences, such as moisture or temperature change and mechanical action (eg B. centrifugal force), the optical axis is unstable and thus receiver and transmitter of the optical transmission units are no longer aligned correctly with each other. This can lead to considerable attenuation and also to complete loss of the optical signal transmission. In particular, when using "single mode" or "multimode" fibers with a relatively small core diameter (typically in the order of up to 100 μηη and sometimes down to <10 μηη) is an exact alignment of the optical components indispensable. The maximum allowable errors in axial displacement or tilt of the optical axes of respective optical components are 60 μηη or less for axial displacement and 0.05 ° or less for tilting, if damping of more than 2.5 dB is avoided want. These error tolerances can not be met with the conventional methods and devices in the rule.

According to other methods, adjusting elements and in particular adjusting screws are provided, with the help of which the sleeve female receiving element with respect to the bearing axis in the rotor or stator can be moved and tilted to compensate for the misalignment between the optical axis and the bearing axis, because of the punctual loading of Justierflächen By adjusting screws, however, such device are not long-term stability and often need to be readjusted. At greater mechanical load, such as at higher speeds, the adjustment of such devices is lost very quickly. Since the rotor and the first optical component rotating therewith are generally subjected to stronger vibrations and forces than the stator fixed to the stationary machine part, the present invention concentrates primarily on the adjustment and fixing of the first optical axis with respect to the rotor , Preferably, however, analogous measures are also to be applied to the adjustment and fixation of the second optical axis with respect to the stator. Compared to the aforementioned prior art, the present invention is therefore based on the object to provide an optical rotary transformer with the features mentioned above and a method for its production, which allow, in particular the error tolerances for the alignment of the optical axis relative to the axis of rotation drastically reduce the rotor and make it much more stable over time. In particular, the process for the preparation should be as simple and safe. This makes it possible to also use the high-quality optical fibers required for high data rates, which have relatively small core cross-sections and their use is possible only if very close fault tolerances are maintained. Of course, the present invention is also applicable when using optical fibers having substantially larger cross-sections and are more tolerant to fault, whereby the use of such optical fibers, the possibly occurring attenuation during transmission is significantly reduced.

With regard to the rotary transmitter itself, the object underlying the invention is achieved in that the surfaces of the rotor determining the position and orientation of the optical axis outside the first bore are machined such that the first axis (12) faces the first bearing axis (16). is misaligned while the first optical axis (14) coincides with the first bearing axis (16). In other words, no adjustments are made in the bearing area on the rotor during assembly with the stator and there are no adjustment means such as special screws or the like provided, but the first optical axis alone by processing the corresponding surfaces, which is the position of the first axis Define to the bearing seat, from the outset, more precisely after the fixation of the component in the rotor, by the geometry of the first bearing seat defined first bearing axis coincides.

Accordingly, the basic principle of the present invention is that all components of the rotary transformer are firmly and uniquely positioned against each other and have no play, in particular no adjustment play and no intermediate adjustment devices, with any contiguous surfaces of parts of the rotor and / or the bearing seat of the rotor so are configured so that the optical axis coincides with the first bearing axis (which is also the axis of rotation of the rotor,), which in turn has the consequence that the first bearing axis and the first axis of the sleeve of the optical component no longer coincide. The unique positioning can be achieved by surface contact of preferably rounded or angled surfaces or by a three-point system non-collinear points, which in turn are not adjustable.

In one embodiment, at least one receiving element is provided between the optical component or its sleeve and a bearing portion of the rotor having the bearing seat. In this case, the contact surfaces between this receiving element and the bearing portion can be edited so that the receiving element on the bearing portion so offset and tilted rests that the optical axis of the component with respect to the bearing seat on the rotor has the desired orientation.

In another embodiment, in which the bearing portion is integrally connected to the receiving element and thus receives the optical component directly in a central bore of the rotor, the bearing seat itself, d. H. the bearing surfaces of the rotor, designed so that it defines a bearing axis, which coincides with the optical axis.

In the first-mentioned variant with a separate from the rotor receiving element, of course, both the contact surfaces between receiving element and rotor and the surfaces of the bearing seat of the rotor to be adjusted accordingly, it being preferable to take only one of these measures, as far as possible.

In this case, the variant in which the component is arranged directly in a bore of a compact rotor, preferred because it manages with fewer components and the production is relatively simple. Concretely, this means that a rotor having a central bore for receiving the optical component and with respect to this central bore has a centrally symmetrical bearing seat, after inserting and fixing the component in the central bore and determining the corresponding optical axis, at its bearing seating surfaces is post-processed, so that they are now centrally symmetrical with respect to the optical axis. It is assumed that precision bearings are used between the rotor and the stator, so that one can definitely expect a precise concentricity of the corresponding bearing. Optionally, however, even certain inaccuracies of a bearing can be compensated by appropriate machining of the bearing seat on the rotor or on the stator.

The unique positioning of the optical axis is then ensured by the seat of the bearing on or in the respective bearing seat.

The term centrally symmetric is to be understood here as a generalization of rotationally symmetrical and includes embodiments with contact points or surfaces which each have the same distance from a common center, without this having to be a closed surface. An example would be one of a splined shaft.

Advantageously, both the first bearing seat and the second bearing seat are nevertheless formed by first or second rotationally symmetrical bearing surfaces. The rotationally symmetric surfaces may in principle be conical surfaces or surfaces of an ellipsoid of revolution, but in the preferred variant cylindrical surfaces, and especially because for cylindrical surfaces corresponding precision rolling bearings are easier to obtain and are much cheaper than specially manufactured for other surfaces bearing.

In this case, according to one embodiment of the invention, the stator has the basic shape of a hollow cylinder which is open at one end and substantially closed at the other end, wherein the closed end face, however, has a central bore, which is referred to here as a "second central bore".

The rotor or its bearing portion has correspondingly the shape of a cylinder or pin with a cylindrical outer surface and is also provided at its one end with a flange-like extension. In addition, axially outside the cylindrical bearing seat surfaces still stepped recesses, tapers or extensions may be provided on the stator or rotor, for example, to accommodate retaining rings for bearings and / or seals therein. Between the bearing seat of the rotor and the bearing seat of the stator is preferably at least one, in particular two, roller bearings arranged, which are preferably precision bearings and have a very low concentricity tolerance.

The inner radius of the bearing seat of the stator is therefore larger by the radial thickness of the rolling bearing than the outer radius of the rotor, these dimensions are of course only for the state of the bearing seat surfaces after appropriate adjustment of the optical components and post-processing of the corresponding bearing seat surfaces apply, which were previously made with allowance ..

In the initial state, therefore, the bearing seat surfaces of the rotor and the stator are preferably made with a certain allowance, that is, it is provided from the outset that of these surfaces still a certain layer must be removed, but not symmetrical about the original axis of the bearing seat surfaces distributed. Rather, the layer thickness to be removed can vary both in the circumferential direction and in the axial direction. In practice, for example, you can proceed as follows:

After an optical component is arranged and fixed in the second central bore, the stator is received in an adjusting or measuring device and rotated about the axis of the adjusting or measuring device, which is also the axis of the bearing seat of the stator in the context of receiving tolerances , In this case, a light signal is emitted via the optical component, which is detected by a detector opposite the second bore. If the optical axis is not aligned with respect to the bearing seat surface of the stator, the light beam emanating from the component on the detector surface describes a more or less offset circle or an ellipse. If this is carried out at two different distances of the detector from the component, then one can determine from the position and the diameter of the circle or the half-axes of the ellipse on the detector surface, the inclination angle and also the radial offset of the optical axis relative to the geometric axis of the bearing seat ,

From the direction of the offset and the angle of inclination, it then follows how much material is to be removed at which axial and circumferential positions of the oversized bearing seat surface, so that the cylindrical inner surface of the stator produced by asymmetric ablation concentric with the optical axis of the built-in optical Component lies. The same process is then repeated with the rotor, that is, first the optical component is received in a bore of the rotor and fixed. Subsequently, the rotor is received in an adjusting or measuring device. By turning the rotor in the adjusting device, in turn, the image or trace of the light beam of the optical component is detected under rotation at two different distances on a sensor located opposite the bore of the rotor. From the position and the radii of the track of the light signal can in turn be determined with which asymmetric distribution in the circumferential direction and axial direction material is removed from the rotor, so that again the result is a cylindrical bearing seat surface, the diameter of the inner diameter of the then corresponds to the rolling bearing and which is centrally symmetrical with respect to the optical axis of the first optical component.

Subsequently, rotor and stator are mounted under arrangement of the corresponding rolling bearing between the bearing seats.

Since the risk of an unstable adjustment of the optical axis in the case of a stator is slightly lower, it would also be possible to limit the measures according to the invention to the rotor and to adjust the optical axis of the stator in a conventional manner. Conveniently, both the bearing seat of the rotor and the bearing seat of the stator have a sufficient axial length to accommodate two bearings between these two parts with sufficient distance can.

The bearings can be axially fixed by corresponding bearing rings both on the rotor and on the stator and moreover at least one or two seals can also be provided axially in front of the roller bearings in order to protect them against contamination. The seals are in particular sliding seals.

If, according to a further embodiment of the invention, an additional receiving element is provided for mounting the first optical element on the rotor, which has a central bore for receiving the optical component and moreover has contact surfaces with which it bears against the rotor and fixed is expediently provided that instead of the bearing seat of the rotor (and possibly also of the stator), the corresponding contact surfaces on the receiving element and / or on the rotor are machined in such a way that when the receiving element is fixed to the rotor, the optical axis with the Rotation axis coincides, even if the receiving element in total then with respect to the optical axis is not (more) centrally symmetrical. The contact surfaces after finishing ment preferably axially parallel and perpendicular thereto radial contact surfaces with respect to the optical axis and the axis of rotation.

The abutment surfaces may also be rotationally symmetric surfaces having axial and radial components. Thus, even if the contact surfaces themselves are not aligned with respect to the optical axis and the axis of rotation, the optical axis and axis of rotation can still coincide within the achievable tolerances.

Axial abutment surfaces are those surfaces which extend axially, ie extend parallel to a corresponding axis, while radial abutment surfaces extend perpendicular to a corresponding axis.

The receiving element is therefore in turn mounted on preferably axially and radially bearing surfaces or on only rotationally symmetrical contact surfaces on the bearing portion of the rotor or stator. The fact that now these contact surfaces are in turn adapted so that the first axis of the receiving element (axis of the receiving bore and the sleeve) and the optical component relative to the axis of rotation of the bearing portion and the associated rotor or stator is offset and tilted in the correct manner, can It can be achieved that the tilting and the offset between the optical axis and the first axis of the receiving element is compensated by the further misalignment between the first axis and the bearing axis or axis of rotation (which is produced by post-processing of the contact surfaces), so that the optical axis and the axis of rotation coincide. This is achieved by appropriate geometrical adaptation of the axial and radial or rotationally symmetrical contact surfaces between receiving element and bearing section, which ensure a uniquely determined surface contact. Since the cavity for the optical component is also adapted to the housing or the sleeve of the first optical component and the optical component thus has no or only slight play in the cavity, the adjustment of the optical axis relative to the axis of rotation will be effected solely by the application of rigid surfaces achieved by adjusting or clamping elements movable surfaces without using thicker adhesive layers and is therefore stable.

In addition, the contact surfaces can be machined with sufficient mechanical precision to be able to meet the required narrow error tolerances which can not or can not be achieved permanently with the conventional technique by adjustment in a filling material and / or adhesive layer.

Preferably, the contact surfaces of the receiving element are machined so that they are aligned with respect to the optical axis, while the contact surfaces of the bearing section so machined. tet or remain so that they are aligned with respect to the axis of rotation. The reverse case, namely alignment of the contact surfaces of the receiving element with respect to the axis of rotation and alignment of the bearing surfaces of the bearing portion with respect to the optical axis but would lead to the same result. In addition, of course, the radial distance of the radial contact surfaces to the corresponding axes with respect to which they are aligned must always be the same, so that finally the optical axis and the axis of rotation coincide.

By "aligned with respect to an axis" is to be understood that, for example, axial abutment surfaces parallel to this axis and radial abutment surfaces with respect to this axis are perpendicular, while rotationally symmetric surfaces are rotationally symmetrical with respect to just this axis. It is understood that axial and radial contact surfaces can also be rotationally symmetrical surfaces at the same time, but need not be rotationally symmetrical.

As already mentioned by way of example, the at least one first optical component should be an optical fiber and at least one collimator lens, for. As a so-called. GRIN lens or a lens combination, which are fixed in a common housing and aligned with each other. By the collimator lens, a parallel, possibly also a waisted beam or light beam is generated. Conveniently, a second optical component, which is arranged on the respective opposite of the rotor or rotary bearing parts, the same structure as the first optical component.

Alternatively, however, at least one of the two optical components may also be a deflection element, such as a mirror, a prism, or an optical grating, for example, only along the optical axis, i. H. must be arranged in the emanating from the first optical component beam of electromagnetic waves or light, in which case, however, the signal from the deflection element in turn must be directed to a further correspondingly aligned optical component having a collimator lens and a fiber or equivalent means.

If, in fact, the rotor or stator in turn has axial and radial abutment surfaces which are not correctly aligned parallel or perpendicular with respect to the axis of rotation, this error can additionally be achieved by reworking the abutment surfaces of the receiving element or, preferably, the rotor or stator, be compensated. In this case, for example, the contact surfaces on the rotor or stator are subsequently processed so that they are correctly aligned with respect to the optical axis. Ultimately, it is a question of manufacturing rationalization, if only the contact surfaces of the receiving element, only that of the rotor or stator, or both, to result in matching the optical axis with the axis of rotation, while geometrical axes of symmetry of the bearing portion and / or receiver generally do not coincide with the axis of rotation. Instead of the axial and radial abutment surfaces (which, of course, in turn may also be rotationally symmetric), only rotationally symmetrical contact surfaces, each having axial and radial components, such as conical surfaces may be provided, wherein at least one of these conical contact surfaces, ie either on the bearing section or on the receiving element is machined so that its associated cone axis is misaligned with respect to the axis of rotation and the optical axis in exactly the way that the error between the optical axis and axis of rotation is balanced except for the inevitable tolerance deviations. Such conical surfaces are also suitable for unambiguously fixing the radial position and the angular orientation of the receiving element relative to the bearing section. It goes without saying that all the measures which have been described above for the production and machining of axial and radial abutment surfaces can be transferred in an analogous manner to the abovementioned rotationally symmetrical abutment surfaces (eg conical surfaces). In the case of conical abutment surfaces, however, it may be more expedient not to carry out the post-processing in such a way that the conical surfaces are rotationally symmetrical with respect to the optical axis and axis of rotation.

In the original state, therefore, the receiving element and rotor (or stator) may have mutually matching conical bearing surfaces, which are aligned concentrically with respect to the axis of rotation and the geometric axis of the receiving element. Ideally, the geometric axis and the axis of rotation also coincide in this initial state. However, since after arranging the optical component in the receiving element, the optical axis and the geometric axis and thus also the optical axis and the axis of rotation no longer coincide, the geometric axis of at least one of the parts (receiving element and bearing portion) with respect to the axis of rotation is so offset and tilted in that the optical axis and the axis of rotation coincide again. For this purpose, the conical surface designed as an inner cone can expediently be reworked accordingly, the conical surface of the rotor preferably being designed as an inner cone. However, this usually means that none of the conical surfaces is more rotationally symmetrical with respect to the optical axis or axis of rotation.

The (post-) processing of the contact surfaces can be done for example by machining or grinding.

At least the first optical component may comprise an optical fiber, which in one embodiment of the invention is a "singlemode" or "multimode" fiber. While single mode fibers may have a fiber core diameter in the range of 3 to 12 μηη, preferably in the range of 5 to 1 μηι μηι, the corresponding diameter of multimode fibers is more in the range of 50 to 60 μηη possibly up to 100 μηη or above, requires but also a precise alignment and bundling of the electromagnetic waves on the fiber core. More preferably, a singlemode fiber has a fiber core diameter of about 9 μm.

According to one embodiment of the invention, the alignment of the optical axis with respect to the axis of rotation takes place with a maximum radial offset and / or angular error, which is a damping during the signal transmission from the one optical component to the other optical component of less than or equal to 3 dB, preferably of less or less than 2.5 dB.

In particular, according to one embodiment of the invention, the optical axis should be tilted relative to the axis of rotation at a relative angle of less than 0.1 °.

Conveniently, the imaging figure is detected at two different distances between the optical component and the detector, so that the position and angular orientation of the optical component can be calculated even better (for example using the radiation set). Otherwise, the position of the axis of rotation with respect to the detector system must be known in order to be able to derive displacement and angular tilting of the optical axis from only one imaging figure generated on the detector by the optical component during rotation with the alignment shaft. Further advantages, features and possible applications of the present invention will become apparent from the following description of a preferred embodiment and the associated figures. Show it:

1 shows a first embodiment of a rotary transformer according to the invention,

FIG. 2 shows the rotor according to the first embodiment,

3 shows the stator and a retaining ring,

Figure 4 shows a variant of an optical rotary transformer with receiving elements before

Correction of contact surfaces,

5 is a schematic representation of the surfaces to be removed on a receiving element of a rotor, FIG.

Figure 6 shows the final seat of the receiving element in the rotor after machining

Contact surface and

Figure 7 shows another variant with conical contact surfaces. One recognizes in FIG. 1 a rotary transformer according to the invention which is designated as a whole by 100 and essentially consists of a rotor 10 and a stator 20 as well as a retaining ring 40 and two roller bearings 31, 32.

First, the rotor will be described according to FIG.

The rotor 10 consists of a bearing portion 15 in the form of a cylindrical pin with a flange 18 at one end and a stepped transition from the bearing portion 15 to the flange 18, which forms an abutment collar 33. An optical component 13 is suitably received in a central bore 1 1. The optical device 13 has an optical axis 14, which is shown in phantom and which deviates recognizably from the first axis 12, which is the geometric axis of the central bore 1 1 and which is also the axis of the cylindrical bearing seat 17 in an initial state, which is still referred to as the first bearing axis 16 to distinguish it from the axis 12 and is not shown separately in Figure 2, since it coincides with the axis 12. The rotor consists essentially of a single piece (apart from a bearing ring 36), so that it can not be distinguished between a receiving element and Lagerabschbitt here. FIG. 3 shows a stator 20 in the left partial image. The stator 20 is a substantially hollow-cylindrical component, with an open end side 28 and a closed end side 28, wherein the closed front side 28 has a central bore 21 in which an optical component 23 is fittingly received. Here again, the first axis 22 of the central bore 21 (which coincides with the geometrical axis 26 of the cylindrical bearing seat surface 27 before corresponding machining) deviates from the geometrical axis 24 of the optical component 23.

Expediently, the bores 11 and 21 have a diameter matched to the outer diameter of the sleeves of the optical components 13 and 23, so that the components 13, 23 sit essentially free of play in their bores 11 and 21 and in addition to the example by a thin adhesive layer can be fixed, which has no effect on the long-term stability of the position of the optical axis.

FIG. 1 shows the assembled state of rotor 10 and stator 20, which, however, can only take place after machining of the bearing seats 17 and 27. Once the bearing seats 17 and 27 are revised so that their axes 16 and 26 now with the optical axes 14th or 24 coincide and their diameter to the inner and outer diameters of the rolling bearings 31, 32 correspond.

However, before the rotor and stator can be assembled in this way, the bearing seats 17 and 27 have been reworked with respect to the initial situation shown in Figures 2 and 3, so that their axes 16 and 26 now no longer with the axis 12 and 22, but coincide with the axes 14 and 24 respectively. In this case, the axes 14 and 24 are aligned accordingly.

It is understood that for this purpose, both the cylindrical inner surface of the stator 20 and the cylindrical outer surface 17 of the rotor are first made with a certain excess, in order then ablate sufficient material according to the radial offset and the tilting of the optical axes 14 and 24 respectively so that the final surfaces 17, 27 are rotationally symmetric with respect to the axles 14, 24, respectively, and at the same time have the proper diameter for the roller bearings 31, 32.

The result is a rotary transformer on which the positions of all axes are fixed to one another unambiguously and immovably and even in prolonged use, by wear, vibration, etc. remain virtually unchanged, as long as the bearings 31, 32 are knocked out. However, there are neither thick layers of adhesive nor any adjustment elements that could move or tilt the optical axes 14, 24 over time and with vibrations or forces occurring. This makes it possible to transmit optical signals directly from the rotor to the stator or vice versa with very high quality.

FIG. 4 is an alternative embodiment of the present invention in which separate receiving elements 2, 45 are provided by the bearing section 15 / flange 18 and the stator body 25 '.

Again, it can be seen that the optical axis 14 of a component 13 deviates from the geometric axis 12 of the bore of the receiving element 2, as well as the optical axis 24 deviates from the geometric axis 22 of the receiving element 45 and its bore. In addition, here the axis 16 is located, which is the axis of rotation of a (not shown) pair of rolling bearings between the rotor 10 'and stator 20'. In the illustrated arrangement, the axis of rotation 16 coincides with the axes 12 and 22 of the receiving elements 2 and 45, respectively. Figure 5 shows an image of a partially assembled rotary transformer according to Figure 4, wherein on the receiving element 2 by an additional narrow hatching the areas are indicated, which must be removed from the surfaces 6 and 7 of the flange of the receiving element 2, so that the optical axis 14th the desired orientation along the axis of rotation

16 receives.

It should be noted, however, that the construction state indicated in FIG. 5 does not actually exist in the preferred variant, since here too the flange of the receiving element 2 is made with an allowance and would not fit into the cylindrical recess in the flange 18 of the rotor 10 'with this allowance , In a measuring and adjusting device, however, the offset of the optical axis 14 and its tilt relative to the axis 12 of the receiving element 2 can be determined and the surfaces 6, 7 of the flange of the receiving element are then processed in a corresponding manner, so that the surface 6 perpendicular to optical axis 14 runs and the peripheral surface 7 of the flange concentric and parallel to the axis 14, wherein the outer diameter of the flange on the receiving element 2 then coincides with the inner diameter of the corresponding recess on the flange 18 of the rotor, so that receiving element 2 and rotor 10 'can be assembled in the manner shown in Figure 6. In this case, the surfaces 6, 7 on the corresponding surfaces 6 ', 7' of the recess of the rotor flange 18 at.

The corresponding contact surfaces 7 'and 6' of the recess of the flange 18 (see Figure 4) are in turn concentric or perpendicular to the axis of rotation 18, through the bearing seat

17 of the bearing section 15 is determined.

Basically, it would of course also possible to make the flange of the receiving element 2 from the outset suitable for the recess in the flange 18 of the rotor 10 'and instead of the contact surfaces 6, 7 in this embodiment to edit the bearing seat 17 so that the optical axis 14 with the Rotation and bearing axis 16 coincides.

Figure 7 shows yet another embodiment in which instead of the mutually perpendicular surfaces 6 and 7 conical contact surfaces 8 are provided, which allow, as can be seen from the upper part of Figure 7, receiving element 2 'and rotor 10 "first in order to measure the deviations of the axis 14 from the axis 12, and then subsequently to work the conical surfaces 8 so that the receiving element is correspondingly tilted and radially offset so that the axis 14 coincides with the bearing axis. It is understood that the deviations and corrections, as indicated in Figures 5, 6 and 7, in reality, significantly weaker, since the deviations of the axes 14 and 12 from each other and analogous to the axes 24 and 22 from each other significantly lower are, as indicated in the figures and thus also to be made to the contact surfaces 6, 7 and possibly also to the bearing seats 17, 27 corrections are much weaker than indicated in the figures.

For purposes of the original disclosure, it is to be understood that all such features as will become apparent to those skilled in the art from the present description, drawings and dependent claims, even though they have been specifically described only in connection with certain further features, both individually and can be combined in any combination with other features or feature groups disclosed herein, unless this has been expressly excluded or technical conditions make such combinations impossible or pointless. On the comprehensive, explicit representation of all conceivable combinations of features and the emphasis on the independence of the individual characteristics of each other is omitted here only for the sake of brevity and readability of the description.

Claims

P a n t a n s p r e c h e

Optical rotary transformer for the direct transmission of an optical signal between a stationary and a rotating machine part, with

a rotor (10) having a bearing portion (15) with a first bearing seat (17) defining a first bearing axis (16), wherein a first optical component (13) having a first optical axis (14) in a first bore is received in the rotor, and

a stator (20) having a second bearing portion (25) with a second bearing seat (27) defining a second bearing axis (26), one optical component (23) having a second optical axis (24) in a second central axis Bore (21) in the stator (20) is arranged, wherein a sleeve of the optical component or the sleeve fittingly receiving the first bore defines a first axis (12) which does not coincide with the first optical axis and wherein the first and second optical Axes aligned with the axis of rotation of the rotor are characterized in that the position and orientation of the optical axis defining contact surfaces of the rotor outside the first bore are machined such that the first axis (12) relative to the first bearing axis (16) is misaligned while the first optical axis (14) coincides with the first bearing axis (16).

Optical rotary joint according to claim 1, characterized in that the bearing section is integrally formed with the part having the first central bore and the bearing seat (17) is machined such that the first axis (12) is misaligned with respect to the first bearing axis (16). while the first optical axis (14) coincides with the first bearing axis (16).

Optical rotary joint according to claim 1 or 2, characterized in that the first and second bearing axes (16, 26) are so misaligned with respect to the first and second axes (12, 22) that the first optical axis (14) with the first bearing axis (16) and the second optical axis (24) coincides with the second bearing axis (26) by the position and orientation of the optical axis defining contact surfaces of the rotor and the bearing outside of the first and the second bore machined so that at a rotor (20) assembled with the stator (10) via the aligned first and second bearing seats (17, 27) also coincide with the first and second optical axes (14, 24). Optical rotary transformer according to one of the preceding claims, characterized in that the first and second bearing seats (17, 27) are produced by reworking previously produced with oversize bearing seats.

Optical rotary transformer according to claim 1, characterized in that the rotor has a separate from the bearing portion receiving element, in which the first bore is arranged with the optical component, said receiving element and bearing portion having mating contact surfaces, which when abutting each other, the position of the first optical Set axis and the first axis, wherein the abutment surfaces with respect to the first optical axis are centrally symmetrical and misaligned with respect to the axis of the first bore.

Optical rotary transformer according to claim 5, characterized in that the contact surfaces each comprise a planar and a perpendicular cylindrical surface.

Optical rotary transformer according to claim 5, characterized in that the contact surfaces each comprise a conical surface.

Optical rotary transformer according to one of the preceding claims, characterized in that the first bearing seat (17) and / or the second bearing seat (25) by first and second rotationally symmetrical bearing surfaces (17, 27) are formed.

Optical rotary transformer according to one of the preceding claims, characterized in that between the first and the second bearing seat at least one rolling bearing (31, 32) is arranged.

Optical rotary transformer according to one of the preceding claims, characterized in that the stator has the basic shape of a hollow cylinder open at one end face, wherein a closed end face has the second central bore.

Optical rotary joint according to one of the preceding claims, characterized in that the rotor (20) has the shape of a cylindrical pin (18) with a flange-like extension at one end.

Optical rotary transformer according to one of the preceding claims, characterized in that a respective bearing ring (19, 29) is provided at the open end of the stator and at the free end of the rotor pin for axially fixing the at least one rolling bearing.

13. Optical rotary joint according to one of the preceding claims, characterized in that the area between the first and the second bearing seat is sealed against the external environment.

14. Optical rotary joint according to one of the preceding claims, characterized in that at least one of the bearing rings has a recess for receiving a sliding seal. 15. A method for producing a rotary optical feedthrough for the direct passage of an optical signal between a stationary and a rotating machine part, with

a stator (20) having a second bearing portion (25) with a second bearing seat (27) defining a second bearing axis (26), one optical component (23) having a second optical axis (24) in a second central axis Bore (21) is arranged in the stator (20), wherein the component receiving the first bore defines a first axis (12) which does not coincide with the first optical axis and wherein the first and second optical axes are aligned with the axis of rotation of the rotor characterized in that, for alignment of the first and second optical axes, the bearing surfaces of the rotor defining the position and orientation of the first optical axis are machined outside the first bore such that the first axis (12) is misaligned with respect to the first bearing axis (16), while the first optical axis (14) coincides with the first bearing axis (16).

16. A method for producing an optical rotary feedthrough according to claim 15, characterized in that the position and orientation of the optical axis defining contact surfaces of the rotor outside of the first bore are first prepared with an abradable the oversize, whereupon the misalignment of the first and / or second optical axis is detected and measured with respect to the first and second axes, respectively, and depending on the degree of misalignment, the oversized bearing surfaces are reworked such that the post-processed surfaces after the Assembly of the rotary transformer with respect to the first and second optical axis (s) are centrally symmetrical and misaligned with respect to the first and second axes.

A method for producing an optical rotary feedthrough according to claim 15 or 16, characterized in that the bearing portion is formed integrally with a receiving the first bore and the first optical component receiving element.

Method for producing an optical rotary feedthrough according to one of Claims 15-17, characterized in that the surfaces previously produced with oversize are the first and / or second bearing seats.

A method for producing an optical rotary feedthrough according to claim 15-18, characterized in that the first bearing seat and / or the second bearing seat are produced as the first and second rotationally symmetrical bearing surfaces.

A method for producing an optical rotary feedthrough according to one of claims 15-19, characterized in that a separate from the bearing portion receiving member is provided, which are assembled with mating contact surfaces, wherein the contact surfaces at least partially as a flat and a perpendicular thereto cylindrical surface become.

Method for producing an optical rotary leadthrough according to one of Claims 15 to 20, characterized in that prior to assembly, the stator and / or the rotor are each clamped in an adjusting device rotatable about an adjusting axis and aligned such that the optical axis (14, 24 ) coincides with the alignment axis, whereupon the position of the optical axis (14, 24) determining surfaces on the rotor are machined outside the first bore to final dimension and on a concentric with respect to the optical axis shape.

22. A method for producing an optical rotary feedthrough according to any one of claims 15 - 21, characterized in that between the first and the second bearing seat at least one rolling bearing is arranged.

23. A method for producing an optical rotary feedthrough according to claim 22, characterized in that the at least one rolling bearing is axially fixed by a respective bearing ring at one end of the rotor and at one end of the stator. A method for producing an optical rotary feedthrough according to claim 23, characterized in that the bearing rings and rotor and stator each have threads and are bolted directly to one another via these threads