Receiver device for a rotary encoder

Abstract

Receiver device, in particular light receiver device, for a rotary encoder (10), which has at least two receiving elements (18a-b) in a series arrangement adapted to a first measuring track (16) of the rotary encoder (10) with code elements on a first circle with a first radius r1 at a first angular distance ϕ1 and thus enables the scanning of the first measuring track (16), characterized in that the arrangement of the receiving elements (18a-b) for two different radii (r1, r) 2) is optimized of dimensional tracks (16) and thus also enables scanning of a second dimensional track (16) of a rotary encoder (10) with code elements on a second circle with a second radius r2 at a second angular distance ϕ2.

Description

[0001] The invention relates to a receiver device for a rotary encoder, a rotary encoder device and a method for determining an arrangement of receiving elements according to the preamble of claims 1, 11 and 12.

[0002] A rotary encoder, also known as an angle sensor or rotary encoder, is used to detect the angle of rotation or angular position of, for example, a shaft in a drive element. An important application is in motor feedback systems, where the encoder in a servo motor reports the actual rotational speed back to the control system. Various physical measurement principles are employed. Often, an optical measurement principle is used, where a light source illuminates or passes through a modulator with a measuring scale, and this light is detected in a receiver.

[0003] The modulator, for example, is a code disk rotating relative to the light source and receiver. This disk serves as a measure of transmission, featuring optically transparent and opaque areas for transmitted light and reflective and absorbing areas for incident light. These areas, or code elements, can be apertures, reflective or diffractive structures, prisms, structures varying in shade of gray or color, and other optically distinguishable elements. Together, the code elements form a measurement track, thereby generating an illumination pattern and, through rotation, a local modulation of the light incident on the receiver.

[0004] The corresponding modulated received signal from the receiver is evaluated to obtain the desired angular information. Sine / cosine encoders are particularly common; these generate a sine and a cosine signal each using two receiving elements with a 90° phase shift. However, systems with more receiving elements also exist, for example, to obtain differential signals with additional negative sine and cosine signals, other phase differences such as 120°, or other non-sinusoidal modulations. Often, there is more than one sampled measurement track, for example, an absolute and an incremental track.

[0005] Fig. Figure 10 shows a conventional optical receiver device 100 with, by way of example, six photodiodes 102. The scale 104, consisting of a multitude of code elements 106, typically forms a concentric arrangement around the axis of rotation, whereby tolerances result in a certain eccentricity, which is only mentioned here and not considered further. The scale 104 therefore exhibits a curvature corresponding to its radius. Fig. However, for the sake of simplicity, no curvature is shown in Figure 10. The photodiodes 102 are arranged for ideal scanning such that they lie on the radius of the scale track 104, their orientation follows the curvature, and their tangential mutual spacing is matched to the spacing of the code elements 106. Therefore, the photodiodes 102 are intuitively located in Fig. 10 each at the same relative position to the assigned code element 106. This achieves a maximum mechanical tolerance against displacement and rotation between receiver device 100 and measuring track 104.

[0006] The conventional receiver device 100 is thus optimized for exactly one radius and one angular distance of a scale track 104. Fig. Figure 11 shows the situation if the receiver device were now used in a different radial position for a measuring track 104 with a different radius and angular spacing. It is clearly visible that the photodiodes 102 are now located in different positions relative to their respective code elements 106. In a favorable case, this reduces the tolerance for displacements and rotations. However, the additional phase differences per photodiode 102 caused by the mismatch can impair the angle measurement, regardless of mechanical tolerances, or it may even make angle measurement impossible. Furthermore, mismatch does not refer to an offset occurring uniformly across all photodiodes 102 that could be corrected by calibration, but rather to an individual additional phase difference or offset between adjacent photodiodes 102, as also shown in [reference missing]. Fig. 11 shown.

[0007] The in Fig. The mismatch shown in Figure 11 prevents the use of the same receiver device for multiple encoder or motor feedback system types with two different diameters and thus two significantly different track radii. In any case, this results in a significant loss of robustness against mechanical tolerances or additional measurement errors.

[0008] Optical rotary encoders often use an opto-ASIC (Application-Specific Integrated Circuit) as the receiver. It is not easy to adapt the arrangement of its photodiodes 102 for a specific scale 104. Instead, a second opto-ASIC must be developed, or two different photodiode arrangements must be accommodated. Both options require significant development and manufacturing costs and also reduce the respective production volumes. However, even with discrete photodiodes, adapting the receiver is a complex process.

[0009] DE 10 2018 212 788 A1 discloses an optical position measuring device with three concentric optical codings, namely two incremental tracks and one absolute track, each of which is assigned a sensor unit. One incremental track has twice the resolution of the other incremental track.

[0010] A similar rotary position measuring device is known from US 6 170 162 B1, in which no optical measuring principle is used, the absolute track is divided into a coarse and fine track, and the resolution of the incremental measuring system is not described in more detail.

[0011] It is therefore the object of the invention to improve a generic receiver device.

[0012] This problem is solved by a receiver device according to claim 1, a rotary encoder device according to claim 11, and a method for defining an arrangement of receiving elements according to claim 12. The receiver device has at least two receiving elements. The rotary encoder preferably operates on an optical principle and is generally described as such here, but non-optical measuring principles are also conceivable. In that case, the receiver device is a light receiver device, and the receiving elements are, for example, photodiodes.

[0013] The receiving elements form a specific arrangement to scan a first measurement track with code elements. The code elements lie on a first circle with radius r1, with each code element having a tangential distance from the others, expressed by a first angular distance ϕ1. All previously mentioned and otherwise known configurations are conceivable for the code elements. The first measurement track can be an incremental track, meaning that another identical code element follows each angular step ϕ1. More complex measurement tracks are also possible, in particular absolute coding.

[0014] The arrangement of the receiving elements is therefore adapted to the first gauge, as exemplified in the introduction by way of the Fig. As explained in section 10, the arrangement is generally a series, but this does not necessarily have to be straight, particularly due to the optimization according to the invention that follows. The arrangement is determined, for example, by the mutual distances of the receiving elements in a radial and / or tangential direction.

[0015] The invention is based on the fundamental idea of ​​optimizing the arrangement of the receiving elements for two different radii. This also makes it possible to scan a second measuring track, whereby the Fig. The mismatch described in section 11 is avoided or at least mitigated. The code elements of the second scale track lie on a second circle with a second radius r2 at a second angular distance ϕ2, where r1 ≠ r2 and / or ϕ1 ≠ ϕ2. The same principles apply to the possible configurations of the second scale track as to the first, although the radius r2 and the angular distance ϕ2 are now the basis for consideration. The rotary encoder with the first scale track is preferably a different device than the rotary encoder with the second scale track. If both scale tracks are scanned in the same device, a way must be provided to separate the modulations from each other, for example, by activating a light source for only one code track using different modes or by means of multiplexing.

[0016] The invention offers the advantage that different scale radii or device diameters can be implemented with the same receiver device. The scales on the different radii may have different resolutions, i.e., angular distances between their code elements. The permissible mechanical tolerances for both radii are optimized. Depending on the design, the optimal state can be maintained for one of the two radii, or the error can be selectively distributed between them. This flexibility reduces manufacturing and development costs and simplifies component management. Furthermore, this does not have to come at the expense of performance compared to receiver arrangements specifically developed for only one variant.

[0017] The receiving elements are preferably arranged relative to each other at the first angular distance ϕ1 with respect to the first circle and at the second angular distance ϕ2 with respect to the second circle. The receiving arrangement is therefore not merely designed to detect the code elements at the respective angular distances ϕ1 with respect to r1 and ϕ2 with respect to r2; it physically replicates these angular distances itself. A radial offset to r1 or r2, and, depending on the embodiment, also a certain tangential offset to ϕ1 and ϕ2, may remain. An offset of at least one of these dimensions is necessary; otherwise, the arrangement would not be optimized for two radii. This is preferably one radius, as will be explained later.

[0018] At least one receiving element preferably has a predetermined phase shift relative to the first angular spacing ϕ1 and the second angular spacing ϕ2. This clarifies what is meant by an arrangement at the respective angular spacing ϕ1, ϕ2. The angular grid of the receiving elements need not be constant; a deliberate individual deviation is permissible, namely by very specific, predetermined fractions of an angular spacing ϕ1, ϕ2 for a particular measurement method. These fractions, or phases, ensure that the receiving elements generate received signals with a mutual phase shift. In this context, a phase of 360° corresponds to an angular spacing ϕ1 or ϕ2. Typical deliberate phases are multiples of 90°, for example, for generating sine / cosine signals using two receiving elements with additional phases of 0° and 90°, or four receiving elements with additional phases of 0°, 90°, 180°, and 270°.Another example is three receiving elements with additional phases of 0°, 120°, and 240°. There can be even more receiving elements with identical additional phases for redundant sampling. These additional phases are, unlike those in... Fig. 11 illustrated fitting errors, with respect to both angular distances ϕ1, ϕ2 being equal.

[0019] The arrangement is preferably optimally designed for the first or second scale. In this embodiment, the starting point of the arrangement according to the invention is a conventional receiver device, which, as is conventional and in Fig. Figure 10 illustrates that the receiver is designed for only one scale track or one radius, which, in the following explanation without loss of generality, refers to the first scale track. For the first scale track, the receiver performs just as well as a conventional receiver. Simultaneously, the scanning of the second scale track is significantly improved. In other words, measurement deviations with respect to the second scale track are minimized without affecting the optimal state with respect to the first scale track. This can be applied to all common arrangements of receiver elements for a single scale track, especially photodiode arrangements, in known rotary encoders or rotary angle sensors.

[0020] The arrangement is preferably optimally designed for the first and second scale tracks with respect to the angular spacing ϕ1, ϕ2. This further ensures that there is no additional matching error when scanning both scale tracks. In this respect, no compromises are necessary; the matching with respect to the angular spacing ϕ1, ϕ2 is just as perfect as in the conventional case for only one scale track. Unavoidable manufacturing tolerances, eccentricities, and the like remain possible, just as in conventional methods. It should be noted that there may still be effects with regard to other parameters, such as the orientation of the individual receiving elements to the code elements or the required extent of the receiving elements and / or code elements. This can be optimized for one scale track, as described in the preceding paragraph, or any residual mismatch can be distributed across both scale tracks.

[0021] The arrangement is preferably described geometrically as follows: - the first circle with radius r1 around a center point M1 and the second circle with radius r2 around a center point M2 touch each other at a point of tangency P0 corresponding to the position of a receiving element, - on the first circle, a position P1 lies at a multiple of the first angular distance ϕ1 to the point of tangency P0, - on the second circle lies a position P2 at a multiple of the second angular distance ϕ2 to the point of tangency P0, and - the radii M1P1¯ and M2P2¯ They intersect at a point of intersection S.

[0022] This is a geometric approach to finding and defining an advantageous arrangement of receiving elements. The arrangement of the two circles with tangential contact initially contradicts intuition, as the measurement marks are much more readily conceived as concentric, and the circles would therefore be more likely arranged with matching centers. However, the aforementioned arrangement with one receiving element at the point of contact is always possible, since all translational degrees of freedom are available with respect to a single receiving element. Only with a second receiving element does the physical arrangement of the receiving elements in the receiver configuration impose boundary conditions. On the first and second circles, positions P1 and P2 are located at multiples of the respective angular distances ϕ1 and ϕ2 to the point of contact P0.This is simultaneously the position of the next code element and the position of the adjacent receiving element of a respective conventional receiver device designed for only one scale. For simplification, the nearest adjacent receiving element is often considered, while multiples of the angular distance take into account the i-th neighbor instead. An additional phase, if desired, is possible, but here, without loss of generality, it is set to 0°. The radii. M1P1¯ and M2P2¯ They intersect at a point of intersection S.

[0023] A receiving element is preferably located at the point of contact P0, and another receiving element is arranged in triangle P1SP2, offset from P1 and P2 in the direction S. The receiving element at the point of contact P0 is the starting point for the geometric considerations and, as already explained, does not impose any restrictions on the arrangement. The other receiving element, however, is not located at P1 or P2 as usual, but is offset in the direction S. The additional condition applies that triangle P1SP2 is not left. This preferably applies to all receiving elements with their respective points P1, P2, and triangles P1SP2.

[0024] The next receiving element is preferably located on the first radius. M1P1¯ or the second radius M2P2¯ The additional receiving element is arranged as follows: It is preferably offset from point P1, P2 only as far as point S and no further, thereby fulfilling and tightening the aforementioned triangle condition. By shifting only along one leg of the triangle, one angular distance ϕ1, ϕ2 is precisely maintained, while the mismatch caused by the offset is reduced for the other angular distance ϕ2, ϕ1. The closer the offset brings the additional receiving element to the intersection point S, the longer the code elements and / or the receiving elements must be in the radial direction.

[0025] The additional receiving element is preferably arranged at the intersection point S. This ensures that the angular distance ϕ1, ϕ2 is precisely maintained for both radii r1, r2. However, the code elements and / or receiving elements must also have a radial extent in which they still overlap sufficiently.

[0026] One of the radii r1, r2 preferably approaches infinity. In the limit, a measuring track then forms a straight line, so that the receiver device can even be used for a rotary encoder on the one hand and a translational system or length measuring system on the other.

[0027] The receiver device is preferably designed as an integrated circuit, in particular as an opto-ASIC (application-specific integrated circuit) with receiving elements configured as light receivers. The considerable effort required for the development and manufacture of an integrated circuit is only incurred once due to the flexibility of its use for two radii r1, r2 of the measuring tracks according to the invention. Alternatively, a discrete design is conceivable, since even then it would be costly to create two different arrangements for two measuring tracks with different radii r1, r2.

[0028] The encoder device according to the invention determines a kinematic quantity of a relative movement of a first object to a second object, wherein a scale is connectable to the first object and a scanning unit for generating a scanning signal by detecting the scale track is connected to the second object. The scale has a first scale track with code elements on a first circle with a first radius r1 at a first angular interval ϕ1 and / or a second scale track with code elements on a second circle with a second radius r2 at a second angular interval ϕ2. A control and evaluation unit determines the kinematic quantity from the scanning signals, in particular an angular position or a quantity derived therefrom such as an angular velocity or angular acceleration.These scanning signals are generated by a receiver device of the scanning unit according to the invention, wherein the receiver device as a whole and the receiving elements therein are as described above for various embodiments. The relative movement is preferably a rotary movement and the encoder device is therefore a rotary encoder, encoder or motor feedback system, but if a radius r1, r2 is set in the limit towards infinity, it can also be a translational or length measuring system.

[0029] The method according to the invention defines or designs an arrangement of receiving elements for two specific dimensional tracks with two radii r1, r2 or angular distances ϕ1, ϕ2. In particular, this provides the configuration for one of the embodiments of a receiving device described above.

[0030] Preferably, the starting point for the configuration is an arrangement of receiving elements optimized for a first measurement track with code elements on a first circle with a first radius r1 at a first angular distance ϕ1, or for a second measurement track with code elements on a second circle with a second radius r2 at a second angular distance ϕ2. This starting point is therefore a conventional arrangement for only one measurement track, although both possibilities are mentioned for the sake of completeness. As seen, the intersection point S provides a way to find an optimum with respect to the angular distance for both measurement tracks without residual errors. However, other parameters, such as the orientation of individual receiving elements or the extent of receiving elements and / or code elements, are optimized for one of the two measurement tracks in this embodiment and therefore remain not entirely optimal for the other measurement track.In this case, the more sensitive or critical scale can be chosen as the starting point, for example the one with the smaller radius r1, r2.

[0031] The method according to the invention can be further developed in a similar manner and exhibits similar advantages. Such advantageous features are described by way of example, but not exhaustively, in the dependent claims following the independent claims.

[0032] The invention is further explained below with regard to additional features and advantages by way of example embodiments and with reference to the accompanying drawing. The illustrations in the drawing show: Fig. 1 a schematic representation of a sensor device with a first diameter; Fig. 2 a schematic representation of another sensor device with a second, here smaller, diameter; Fig. 3 a geometric sketch to illustrate an angular distance with respect to a radius; Fig. 4. A geometric sketch to illustrate an optimization for two radii and angular distances towards the smaller radius; Fig. 5 a representation of a receiving element and its displacement according to the optimization according to Fig. 4; Fig. 6 a representation of a receiver device with several receiving elements, the arrangement of which according to Fig. 4 and Fig. 5 is optimized; Fig. 7. A geometric sketch to illustrate an optimization for two radii and angular distances, now towards the larger radius; Fig. 8 a representation of a receiving element and its displacement according to the optimization according to Fig. 7; Fig. 9 a representation of a receiver device with several receiving elements, the arrangement of which according to Fig. 7 and Fig. 8 is optimized; Fig. 10 a representation of a conventional receiver device relative to a scale for which the receiver device is designed; and Fig. 11 a representation of the conventional receiver device now relative to a scale for which the receiver device is not designed, resulting in a mismatch.

[0033] Fig. Figure 1 shows a schematic representation of a encoder device 10, which is designed as a rotary encoder. Although the invention is described here using the example of an optical encoder device 10, other technologies are also conceivable. The encoder device 10 has a code disk rotating with the shaft 12 as a scale 14, and a code track or scale 16 is located on the scale 14. The scale 16 can be an incremental code track or a more complex code track, for example, for absolute positioning.

[0034] A scanning unit 18 with several light-receiving elements or photodiodes (not shown individually here) scans the scale track 16 during the rotational movement. The light-receiving elements are preferably integrated on an opto-ASIC (application-specific integrated circuit) and receive the light from a light source 20 that penetrates the scale track 16. The scale track 16 acts as a modulator.

[0035] A control and evaluation unit 22 assesses the appropriately modulated sampling signals from the light receiving elements in order to determine the angular velocity and, depending on the embodiment, other kinematic quantities. These output quantities, or quantities derived from them, can be made available at an output.

[0036] The representation of the encoder device 10 in Fig. Figure 1 is very schematic. Therefore, the design of the scanning unit 18 is in Fig. 1 is kept very simple, which, for example, could also operate using transmitted light instead of reflected light. Particularly with regard to the dimensions and specific positions of the components, the encoder device 10 can vary considerably in practice. Fig. 1. In practice, instead of the single scale track 16 shown, two or more scale tracks are usually scanned simultaneously. In this case, an arrangement of light-receiving elements is found multiple times on correspondingly different radii, independently and next to each other. The shape as well as the area of ​​the light-receiving elements or photodiodes on the different radii usually varies.

[0037] Fig. Figure 2 shows another embodiment of a encoder device 10, which differs from that of the figure by a smaller device diameter and a smaller radius of the measuring track 16. Conventionally, this requires a different scanning unit 18 with an arrangement of the light-receiving elements designed for this smaller radius. It is then explained how, according to the invention, one and the same arrangement of light-receiving elements can be used for two different radii. In contrast to the illustration in the Fig. 1 and Fig. 2 However, preferably the scanning unit 18 is not moved as a whole to a different radius, but is arranged in such a way that the same position is suitable for scanning measurement traces in two different radii.

[0038] While the Fig. 1 and Fig. Figure 2 shows encoder devices 10 for a rotary movement; however, an embodiment with a linear movement, i.e., a translational system or length measuring system, is also conceivable. For this purpose, a straight line is considered as a circle with an infinite radius. The measuring body 14 is then elongated, and the scanning unit moves translationally relative to it in the direction of its longitudinal extension.

[0039] To prepare for the explanation of the optimization according to the invention, Fig. 3. A sketch with a circle of radius r around a center point M. This circle is divided into equal sectors with angular spacing ϕ by the code elements. Here, in Fig. In 3 and all subsequent geometric sketches, the angular distance ϕ is chosen to be unrealistically large. While this is not impermissible, and the invention also functions under these conditions, particularly within an angular range of -90° to +90°, large angles do not correspond to the common geometries of a sensor device 10.

[0040] According to this, after each angular step ϕ, the next code element is found; the scale 16 is tangentially subdivided into equidistant sections or increments. Therefore, the surface center P of a light-receiving element is conventionally offset from a first light-receiving element, which here is located at twelve o'clock in position O, by precisely this angular distance ϕ. The position in the tangential direction or the angular distance ϕ of each light-receiving element, preferably represented by the surface center, thus optimally matches the scale. The light-receiving elements are also tangentially equidistant from each other by the angular distance ϕ with radius r. This corresponds to the situation described in the introduction. Fig. 10. However, if this arrangement of light-receiving elements is used for a gauge 16 with a larger or smaller radius, it is only possible with a very limited mechanical tolerance or not at all, since the arrangement of light-receiving elements and code elements is incompatible. This corresponds to the unfavorable situation described in the introduction. Fig. 11.

[0041] Fig. Figure 4 shows another geometric sketch illustrating an optimization of the arrangement of light-receiving elements for use with 16 different radii r1, r2. Here, a first circle and a second circle are similar to the single circle of the Fig. The diagram shows three superimposed elements with radii r1 and r2, respectively, and centers M1 and M2. They touch each other tangentially at a point P0. A light-receiving element can be conceptually located at this point. This is always possible because the entire arrangement of light-receiving elements can be shifted accordingly. In two conventional arrangements of light-receiving elements for radii r1 and r2, the next light-receiving element would be positioned at an angular distance ϕ1 at P1 and at an angular distance ϕ2 at P2, respectively. In the diagram, r1 / r2 ≠ ϕ1 / ϕ2. Conventionally, one would have to choose one of the positions and thus one of the dimension lines 16, since the same light-receiving element cannot be located at both P1 and P2. The direction is considered clockwise without loss of generality.

[0042] In the illustrated embodiment, positions P1 and P2 are merely a starting point. In principle, an arrangement of light-receiving elements could be used as the starting point, one that does not match either the first scale track corresponding to the first circle or the second scale track corresponding to the second circle. Preferably, however, a conventional arrangement for one of the two scale tracks forms the starting point. This is preferably the second scale track with radius r2 and angular spacing ϕ2, and the arrangement is then additionally optimized for the first, larger scale track with radius r1 and angular spacing ϕ1. The reverse approach would also be possible; however, a smaller circle is more challenging to optimize in a rotary encoder 10, so adhering to its optimization is advantageous.

[0043] In Fig. 4 The light receiving element, virtually located at position P1, is moved along the vector v on the radius M1P1¯ in the direction of the intersection point S of the two radii M1P1¯ and M2P2¯ shifted. This improves the adaptation to the angular distance ϕ2, without already having to adjust it initially and everywhere. M1P1¯ to change the ideal phase angle ϕ1. Provided the intersection point S exists and is not too far from P1 and P2, it can be shifted to that point.

[0044] The intersection point S represents an optimum for both radii r1, r2 and angular distances ϕ1, ϕ2. A light-receiving element positioned there fulfills its function with the largest available mechanical tolerance. This is because the radius M1P1¯ only points at angular intervals ϕ1 and the radius M2P2¯ If the system only has points at angular intervals ϕ2, then both conditions are met at intersection point S. If no intersection point S exists, or if the distance between them is too great, the optimization can still be performed. However, the ideal position will not be reached. The optimization is performed analogously if the initial situation is referenced to the other scale and shifted from P2 towards S.

[0045] Depending on the embodiment, however, the line is not deliberately cut all the way to the intersection point S, but only a section along the radius. M1P1¯ or M2P2¯ The angular distance ϕ1, ϕ2 is not necessarily the only optimization criterion. For example, the orientation of the individual light-receiving elements also depends on the radius, and the radial extent of the code elements and / or light-receiving elements must be large enough for them to overlap: a point-like light-receiving element at intersection S would not detect a point-like code element at point P1 or P2, but it would if one and / or the other had sufficient radial extent. These additional optimization criteria may outweigh a residual error in the angular distance ϕ1, ϕ2, which then depends on the individual design.

[0046] Following a similar line of reasoning, it is not only the radii that are considered. M1P1¯ or M2P2¯ shifted, but more generally in triangle P1SP2.

[0047] This allows the angular errors to be weighed against the aforementioned further optimization criteria and specifically distributed across ϕ1 and ϕ2.

[0048] Fig. Figure 5 shows the application of the described optimization for a single light-receiving element, where dashed lines represent a light-receiving element 18a for reading the first scale mark and solid lines represent a light-receiving element 18b for reading the second scale mark. The center point of each light-receiving element 18a-b is also shown, representative of its position, both in its initial position P1 and in the optimized position S after a shift by v.

[0049] Fig. Figure 6 shows the shift and the resulting optimized arrangement for an arrangement with, as an example, six light-receiving elements 18a-b. Each light-receiving element is individually adjusted according to the Fig. The procedure outlined in section 4 has been postponed.

[0050] If, as preferably intended, a conventional configuration is used that is optimized for one of the measuring tracks, the procedure according to the invention is explicitly not a compromise between two radii r1, r2 or angular distances ϕ1, ϕ2 of measuring tracks. The optimization of the initial configuration for one measuring track is retained. At the same time, an additional improvement is achieved for the other measuring track. If the intersection point S is reached, this improvement is even ideal, at least with respect to the radii r1, r2 and the angular distances ϕ1, ϕ2.

[0051] The Fig. 7 to 9 correspond to the Fig. 4 to 6, with the difference that the shift is now in the direction of the larger radius. This is therefore equally possible according to the invention. As already mentioned, it is advantageous if the starting point is an arrangement optimized for the scale gauge 16 with the smaller radius.

[0052] Finally, some parameters or degrees of freedom with respect to which the invention is not limited should be explicitly mentioned. For example, the difference between the two radii r1 and r2, as well as between the two phase angles φ1 and ϕ2, can in principle be arbitrary, although not all configurations have the same practical relevance. The number, shape, and area of ​​the light-receiving elements can vary, with identical shapes and areas being preferred. Multiple arrangements of light-receiving elements on the same radius can be provided to create redundancy, for example, for safety functions. Likewise, additional measuring tracks can be provided on multiple radii, with the associated light-receiving elements also integrated on the same opto-ASIC and their arrangement optimized for their respective measuring tracks.Each arrangement preferably covers two different measuring tracks, thus supporting multi-track devices of varying diameters. Rotated installation is also possible. As briefly mentioned above, the optimization also works for the limiting case r2→∞, enabling flexible use in a rotary encoder device with a first measuring track corresponding to r1 and in a linear encoder device with a second measuring track corresponding to r2.

Claims

[1] Receiver device, in particular light receiver device, for a rotary encoder (10) which has at least two receiving elements (18a-b) in a series arrangement which is adapted to a first measuring track (16) of the rotary encoder (10) with code elements on a first circle with a first radius r1 at a first angular distance ϕ1 and thus enables the scanning of the first measuring track (16), characterized by , that the arrangement of the receiving elements (18a-b) for two different radii (r1, r 2) is optimized of dimensional tracks (16) and thus also enables scanning of a second dimensional track (16) of a rotary encoder (10) with code elements on a second circle with a second radius r2 at a second angular distance ϕ2. [2] Receiver device according to claim 1, wherein the receiving elements (18a-b) are arranged relative to each other at the first angular distance ϕ1 with respect to the first circle and at the second angular distance ϕ2 with respect to the second circle. [3] Receiver device according to claim 2, wherein at least one receiving element (18a-b) has a predetermined phase offset to the first angular distance ϕ1 and the second angular distance ϕ2. [4] Receiver device according to one of the preceding claims, wherein the series arrangement for the first measuring track (16) and the second measuring track (16) is optimally designed with respect to the angular distance ϕ1, ϕ2. [5] Receiver device according to one of the preceding claims, wherein the series arrangement is geometrically described as follows: - the first circle with radius r1 around a center M1 and the second circle with radius r2 around a center M2 touch each other at a point of contact P0 corresponding to the position of a receiving element (18a-b), - on the first circle, a position P1 lies at a multiple of the first angular distance ϕ1 to the point of tangency P0, - on the second circle lies a position P2 at a multiple of the second angular distance ϕ2 to the point of tangency P0, and - the radii M1P1¯ and M2P2¯ They intersect at a point of intersection S. [6] Receiver device according to claim 5, wherein a receiving element (18a-b) is arranged at the contact point P0 and a further receiving element (18a-b) is arranged in the triangle P1SP2 with an offset to P1 and P2 in the direction S. [7] Receiver device according to claim 5 or 6, wherein the further receiving element (18a-b) is located on the first radius M1P1¯ or the second radius M2P2¯ is arranged. [8] Receiver device according to one of claims 5 to 7, wherein the further receiving element (18a-b) is arranged at the intersection point S. [9] Receiver device according to one of claims 1 to 4, wherein one of the radii r1, r2 goes to infinity. [10] Receiver device according to one of the preceding claims, which is designed as an integrated circuit, in particular as an opto-ASIC with receiving elements designed as light receiving elements (18a-b). [11] Encoder device (10) for determining a kinematic quantity of a relative motion of a first object to a second object, wherein the encoder device (10) comprises a measuring body (14) connectable to the first object with a measuring track (16) and a scanning unit (18) connectable to the second object for generating a scanning signal by detecting the measuring track (16) as well as a control and evaluation unit (22) configured to determine the kinematic quantity from the scanning signal, characterized by , that the scanning unit (18) comprises a receiver device according to one of the preceding claims. [12] Method for determining an arrangement of receiving elements in a receiver device for a rotary encoder (10), in particular a receiver device according to one of the preceding claims, characterized by , that a receiving element (18a-b) is arranged at a point of tangency P0 of a first circle with radius r1 around a center M1 and of a second circle with radius r2 around a center M2, and another receiving element (18a-b) is arranged in a triangle P1SP2 with an offset relative to P1 and P2 in the direction S, in particular on the first radius M1P1¯ or the second radius M2P2¯ or on the vertex S, where the vertex P1 on the first circle lies at a multiple of a first angular distance ϕ1 to the point of tangency P0 and the vertex P2 on the second circle lies at a multiple of a second angular distance ϕ2 to the point of tangency P0, and the vertex S is the intersection point of the radii M1P1¯ and M2P2¯ is. [13] Method according to claim 12, wherein the starting point of the determination is an arrangement of receiving elements (18a-b) that is optimized for a first measuring track (16) with code elements on a first circle with a first radius r1 at a first angular distance ϕ1 or for a second measuring track (16) with code elements on a second circle with a second radius r2 at a second angular distance ϕ2.

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