Structure for position measurement

Abstract

To provide a structure for position measurement having a simple and cost-effective structure, and enabling accurate position measurement.SOLUTION: A structure has a support (10) composed of a plurality of portions, and a scale (12) arranged on the support (10). The scale (12) extends in a longitudinal direction (X), and is used for at least position measurement in the longitudinal direction (X). A first stator and a second stator (10.1, 10.5) are configured such that these stators allow movement of first and second edge parts (12.11, 12.21) of the scale (12) perpendicular to a reference axis (S) relative to the support (10), which are arranged so as to face each other in a transverse direction (y), at first and second positions (P1, P2), respectively. The reference axis (S) extends parallel to the longitudinal direction (X).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a structure according to the preamble of claim 1. [Background technology]

[0002] Patent Document 1 discloses a structure having a support and a scale arranged on the support. The scale extends in the longitudinal direction. The scale has measurement graduations arranged on a measurement graduation surface for measuring position in at least the longitudinal direction. The support has a plurality of individual segments. Each of the individual segments of the support is configured as a stator that fixes the scale to the support. Each of these stators has a stator configured from multiple parts (multiple sections).

[0003] Further structures with multiple stators are known from US Pat. No. 5,623,299, US Pat. No. 5,623,299 and US Pat. No. 5,623,299. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] European Patent Application Publication No. 3892962 [Patent Document 2] German Patent Application Publication No. 102005027025 [Patent Document 3] European Patent Application Publication No. 3026389 [Patent Document 4] European Patent Application Publication No. 3705850 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a structure for position measurement that has a simple and cost-effective structure and enables accurate position measurement. [Means for solving the problem]

[0006] This problem is solved according to the invention by a structure having the features of claim 1.

[0007] A structure constructed according to the present invention includes a support and a scale arranged on the support. The scale extends in a longitudinal direction. The scale has measurement graduations arranged on a measurement graduation surface for measuring at least a longitudinal position. The support includes a plurality of individual segments. Each of the individual segments of the support is configured as a stator for fixing the scale to the support. The support includes a first stator and a second stator. The first stator is configured to hold a first cross-sectional portion of the scale at a first position so that it can move freely in the longitudinal direction relative to the support, and to firmly hold the first cross-sectional portion to the support in a lateral direction extending perpendicular to the longitudinal direction. The second stator is configured to firmly hold a second cross-sectional portion of the scale at a second position different from the first position so that it can move longitudinally and lateral directions. The first stator and the second stator are configured to allow movement of first and second edges of the scale, which are arranged at laterally opposing positions, perpendicular to a reference axis relative to the support at the first and second positions, respectively. The reference axis extends parallel to the longitudinal direction.

[0008] Holding a cross section of a scale against or on a support, and allowing an edge of the scale to move against the support, means holding or allowing, when the support is connected, to be based on the part of the support that is firmly (immovably) connected to the base. When the support is connected, holding or allowing is performed not only based on the part of the support that is firmly connected, but also based on the base (reference body).

[0009] The reference axis is preferably the axis of symmetry of the scale.

[0010] Advantageously, the first stator and the second stator are configured such that, when in the first position and the second position, respectively, the stators allow movement of the first edge and the second edge of the scale towards or away from the reference axis relative to the support.

[0011] Furthermore, it is advantageous if the first stator and the second stator are configured such that, in the first position and the second position, respectively, the stators allow symmetrical movement of the first edge and the second edge of the scale with respect to a reference axis relative to the support.

[0012] For example, symmetrical movement of the first edge or the second edge may be affected by thermal expansion or contraction of the scale relative to the support, which may also be caused by differences in the thermal expansion coefficients of the scale material and the support material.

[0013] It is preferable that the first stator and the second stator are each integrally (i.e., not made up of multiple parts) constructed (so-called monolithic structure).

[0014] Preferably, the first stator, the first cross-section of the scale, the second stator, and the second cross-section of the scale are directly connected to each other, for example by a first or second material-bonding connection, preferably a hardened connection. Direct connection to each other means that the respective elements are connected to each other directly, i.e., without one or more intermediate elements (e.g., intermediate supports).

[0015] Advantageously, the individual segments of the support are arranged separated from one another in the longitudinal direction.

[0016] Furthermore, it is advantageous if the individual segments of the support are distributed in the longitudinal direction, for example evenly spaced.

[0017] The first stator is preferably configured to hold the first cross-sectional portion of the scale firmly to the support in the height direction (degree of freedom Z) in the first position, and the second stator is preferably configured to hold the second cross-sectional portion of the scale firmly to the support in the height direction (degree of freedom Z) in the second position.

[0018] Preferably, the measuring scale is used for position measurement in the in-plane degrees of freedom (i.e., degrees of freedom X, Y, R and Z). Additionally, the measuring scale may be used for position measurement in further degrees of freedom (e.g., degrees of freedom Z, RX, RY).

[0019] For example, the measuring graduation is an incremental graduation. Alternatively, the measuring graduation may be an absolute graduation, for example configured as a pseudo-random code.

[0020] The present invention allows, on the one hand, a simple and cost-effective construction and, on the other hand, a highly accurate position measurement. For this purpose, in particular, a multi-part support (i.e., individual segments of the support) is provided for connecting the support to a substrate (e.g., a machine bed). Furthermore, the individual segments of the support form a plurality of stators. The stators are used, on the one hand, for (local) fixed fixation of the scale cross-section relative to the support (hereinafter referred to as external local fixed fixation) and, on the other hand, for (respectively local) decoupling of the scale cross-section relative to the support (hereinafter referred to as external local decoupling). The external local fixed fixation is performed at least with respect to the X and Y degrees of freedom. Furthermore, the external local decoupling is performed in the X degree of freedom. In order to achieve the external local decoupling, in particular, a first stator (hereinafter referred to as a flex element) is provided. Furthermore, a second stator (hereinafter referred to as a fixed point element) is provided to achieve the external local fixed fixation. The flex element and the fixed point element further provide a (respectively local) decoupling of the edge of the scale from the support (hereinafter referred to as internal local decoupling), where the internal local decoupling is performed in the degree of freedom Y. Due to the external local decoupling as well as the internal local decoupling, effects caused by temperature changes (e.g. binding forces between the support and the scale) are avoided or at least reduced, which allows for a generally accurate position measurement.

[0021] Advantageous embodiments of the invention emerge from the dependent claims.

[0022] Further details and advantages of the invention will be explained on the basis of the following description of an embodiment of the invention in conjunction with the drawings. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view of an exemplary structure. [Figure 2] FIG. 2 is a plan view of the structure of FIG. 1. [Figure 3a]FIG. 2 is a perspective view of a first portion of the structure of FIG. 1. [Figure 3b] FIG. 3b is a plan view of the first portion of FIG. 3a. [Figure 4a] FIG. 2 is a perspective view of a second portion of the structure of FIG. 1. [Figure 4b] FIG. 4b is a plan view of the second portion of FIG. 4a. [Figure 5a] FIG. 3b is a perspective view of the first stator of the first section of FIG. 3a; [Figure 5b] FIG. 5b is a plan view of the first stator of FIG. 5a; [Figure 5c] FIG. 5b is a bottom view of the first stator of FIG. 5a. [Figure 5d] FIG. 10 is a perspective view of an exemplary alternative first stator. [Figure 6a] FIG. 4b is a perspective view of the second stator of the second part of FIG. 4a. [Figure 6b] FIG. 6b is a plan view of the second stator of FIG. 6a. [Figure 6c] FIG. 6b is a bottom view of the second stator of FIG. 6a. [Figure 6d] FIG. 10 is a perspective view of an exemplary alternative second stator. [Figure 7a] 5b is a perspective view of the first stator of FIG. 5a in a first bent state. [Figure 7b] FIG. 5b is a perspective view of the first stator of FIG. 5a in a second bent state. [Figure 8] FIG. 6b is a perspective view of the second stator of FIG. 6a in a flexed state. [Figure 9a] FIG. 3b is a cross-sectional view taken along section line AA of FIG. [Figure 9b] FIG. 4b is a cross-sectional view taken along section line BB of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0024] Identical or functionally identical elements are given the same reference numerals in the figures.

[0025] An embodiment of the present invention will be described below with reference to Figures 1 and 2. This exemplary structure comprises a support 10 and a scale 12 arranged on the support 10. The scale 12 extends in a longitudinal direction (main measuring direction) X and has measuring graduations 14 arranged on a measuring graduation plane A1 (i.e., see Figure 9a or 9b, X / Y plane). The measuring graduation 14 is configured as an incremental graduation capable of photoelectric scanning for high-precision position measurement in the longitudinal direction X as well as in a second transverse direction Y extending perpendicular thereto. The scale 12 has a negligibly small thermal expansion coefficient, in particular a thermal expansion coefficient α of 1.5 x 10 in the temperature range from 0°C to 50°C. -6 K -1 Smaller than 0.1 x 10 -6 K -1 Preferably, the material is a glass or glass ceramic (e.g., Zerodur) or a metal, such as Invar.

[0026] The support 10 has a thermal expansion coefficient of approximately 10.5×10 -6 K -1 It is preferable that the steel be made of

[0027] The support 10 includes a plurality of individual plate-shaped segments 10.1 to 10.9. Each of the individual segments 10.1 to 10.9 of the support 10 is configured as a stator that fixes a scale 12 to the support 10. The scale 12 is configured in the shape of a rectangular parallelepiped (see FIG. 1).

[0028] The support 10 comprises a first stator (segment 10.1) and a second stator (segment 10.5). The first stator 10.1 is sometimes called a flex member. The second stator 10.5 is sometimes called a fixed point member.

[0029] The structure shown in Figure 1 is placed on a base 1 (e.g. a machine bed or other carrier). To fix the structure to the base 1, screws 2 are provided. The screws 2 extend through the individual segments 10.1 to 10.9 into the base 1. The base 1 consists, for example, of a material (e.g. granite or aluminum) whose thermal expansion coefficient differs from that of the scale 12 and / or the support 10.

[0030] The first stator 10.1 is configured to hold a first cross-sectional portion 12.1 (see FIG. 9a) of the scale 12 at a first position P1 (see FIG. 3b) so as to be freely movable in the longitudinal direction X relative to the support 10, and to hold it firmly to the support 10 in the lateral direction Y. The second stator 10.5 is configured to hold a second cross-sectional portion 12.2 (see FIG. 9b) of the scale 12 at a second position P2 (see FIG. 4b) different from the first position P1 so as to hold it firmly to the support 10 in both the longitudinal direction X and the lateral direction Y.

[0031] Therefore, the first stator 10.1 allows, so to speak, the first position P1 to be disconnected / fixed in position with respect to the degrees of freedom: X_external release, Y_external constraint. Therefore, the second stator 10.5 allows, so to speak, the second position P2 to be fixed in position with respect to the degrees of freedom: X_external constraint, Y_external constraint.

[0032] The first stator 10.1 and the second stator 10.5 are configured such that the stators allow movement of two first edges 12.11 (see FIG. 9a) and two second edges 12.21 (see FIG. 9b) of the scale 12, which are positioned opposite each other in the transverse direction Y, in a direction perpendicular to a reference axis S (see FIG. 2) relative to the support 10, at a first position P1 and a second position P2, respectively. As shown in FIG. 2, the reference axis S extends parallel to the longitudinal direction X.

[0033] The first stator 10.1 and the second stator 10.5 therefore allow, so to speak, decoupling with respect to the degree of freedom: Y_internal release in the first position P1 or in the second position P2.

[0034] Referring to FIG. 2, the reference axis S is the axis of symmetry (ie, the central axis) of the scale 12 .

[0035] The first stator 10.1 and the second stator 10.5 are configured to allow movement of the first edge 12.11 and the second edge 12.21 of the scale 12 relative to the support 10 toward or away from the reference axis S when the stators are in a first position P1 and a second position P2, respectively. Movement toward the reference axis S refers to movement of the first edge 12.11 or the second edge 12.21 inward in opposite directions, i.e., toward the central axis of the scale 12. Movement away from the reference axis S refers to movement of the first edge 12.11 or the second edge 12.21 inward in opposite directions, i.e., away from the central axis of the scale 12.

[0036] The first stator 10.1 and the second stator 10.5 allow symmetrical movement of the first edge 12.11 and the second edge 12.21 of the scale 12 in the first position P1 and the second position P2, respectively, about the reference axis S relative to the support 10. Symmetrical movement is understood here to mean that the first edge 12.11 or the second edge 12.21 moves equally in terms of magnitude and / or direction of movement.

[0037] Figure 3a shows a perspective view of a first portion of the structure of Figure 1. The first portion of Figure 3a has a first stator 10.1 (flex member). Figure 4a shows a perspective view of a second portion of the structure of Figure 1. The second portion of Figure 4a has a second stator 10.5 (fixed point member). A more detailed description of the first stator 10.1 and the second stator 10.5 follows.

[0038] It should be noted that the other stators (ie, the individual segments 10.2-10.4 and 10.6-10.9 in FIG. 1) are each constructed similarly to the first stator 10.1.

[0039] Figures 5a-5c show the first stator 10.1 from various perspectives, and Figure 5d shows a perspective view of an exemplary alternative first stator 10.1a that can be part of the structure of Figure 1 in place of the first stator 10.1.

[0040] As shown in FIG. 5a, the first stator 10.1 includes a first segment 16.1 that secures the first stator 10.1 to the base 1, a second segment 16.2 that holds the scale 12 and is connected to the first segment 16.1, and a third segment 16.3 and a fourth segment 16.4 that secure a first edge 12.11 of the scale 12 to the first stator 10.1 and are connected to the second segment 16.2. The first stator 10.1 includes a first pair of flexure joints 18.1 that are configured to allow movement of the second segment 16.2 in the longitudinal direction X relative to the first segment 16.1. The first stator 10.1 includes a second pair of flexure joints 18.2. The second pair of flexure joints 18.2 are configured such that they allow movement of the third segment 16.3 and the fourth segment 16.4 in the lateral direction Y relative to the second segment 16.2.

[0041] According to Figure 5a, the first segment 16.1 and the second segment 16.2 are connected to each other via a first pair of flexure joints 18.1, and according to Figure 5a, the third segment 16.3 and the fourth segment 16.4 are connected to the second segment 16.2 via a second pair of flexure joints 18.2.

[0042] As can be seen in FIG. 5b, the first pair of flexure joints 18.1 includes two first leaf springs 18.11, 18.12 arranged opposite each other in the longitudinal direction X. The first leaf springs 18.11, 18.12 are oriented perpendicular to the reference axis S. As can be seen in FIG. 5b, the second pair of flexure joints 18.2 includes two second leaf springs 18.21, 18.22 arranged opposite each other in the transverse direction Y. The second leaf springs 18.21, 18.22 are oriented parallel to the reference axis S. Referring to FIG. 5a, the first leaf springs 18.11, 18.12 and the second leaf springs 18.21, 18.22 each extend in a height direction Z. The height direction Z extends perpendicular to the measuring graduation surface A1 (see FIG. 9a or 9b).

[0043] 5a and 9a, the third segment 16.3 and the fourth segment 16.4 are fixed to at least the underside C of the scale 12 (i.e., the side facing the substrate 1) by a first material-bonding connection 20.1. This results in a first fixation of the underside of the scale 12 at the first position P1. The first material-bonding connection 20.1 is preferably a hardened adhesive connection. The adhesive surfaces of the third segment 16.3 and the fourth segment 16.4 for this adhesive connection (i.e., the first material-bonding connection 20.1) are indicated by hatching in FIG. 5a. The first material-bonding connection 20.1 has two adhesive ridges (see FIG. 9a) adjacent to the two lateral surfaces of the scale 12 facing each other in the transverse direction Y. As shown in FIG. 9a, the lateral surfaces of the scale 12 each extend in the longitudinal direction X.

[0044] As shown in Figure 5a, the first stator 10.1 is provided with a first adhesive means 22.1. The first adhesive means 22.1 is an elastically deformable material. The first adhesive means 22.1 is arranged on the upper surface 16.21 of the second segment 16.2 (i.e., the surface facing the scale 12) and in the transverse direction Y between the third segment 16.3 and the fourth segment 16.4. The first adhesive means 22.1 is in particular a sliding adhesive tape (first alternative) or a double-sided adhesive tape (second alternative).

[0045] If the first attachment means 22.1 is a double-sided adhesive tape, the adhesive tape serves to further secure the scale 12 to the first stator 10.1.

[0046] In the first alternative, the first attachment means 22.1 forms a mounting surface for the scale 12. The sliding adhesive tape consists, for example, of a resin layer and an adhesive layer. This adhesive layer secures the sliding adhesive tape to the first stator 10.1. Furthermore, this adhesive layer acts as a compensating element during shrinkage of the first material-bonding connection 20.1 (i.e., the preferably cured adhesive connection). This substantially prevents deformation of the scale 12, which improves the accuracy of the position measurement. In the first alternative, the first attachment means 22.1 also allows the scale 12 to be moved after it has been mounted on the first stator 10.1. This is advantageous when adjusting the position of the scale 12.

[0047] In the second alternative, the first attachment means 22.1 also forms a resting surface for the scale 12. As in the first alternative, the double-sided adhesive tape serves as an advantageous compensation element during shrinkage of the first material-bonding connection 20.1. In the second alternative, the first attachment means 22.1 also allows the scale 12 to be fixed in position immediately after being placed on the first stator 10.1. This allows for flexible assembly positions, in particular the so-called overhead assembly (Ueber-Kopf-Mountage).

[0048] As can be seen from the bottom view of Fig. 5c, the first stator 10.1 is provided with second attachment means 22.2 for fixing the first stator 10.1 to the base 1. The second attachment means 22.2 is a vibration-damping means. The second attachment means 22.2 is arranged on the underside (i.e., the side facing away from the scale 12) surface 16.22 of the second segment 16.2 and in the transverse direction Y between the third segment 16.3 and the fourth segment 16.4. The second attachment means 22.2 is in particular a double-sided adhesive tape.

[0049] For example, the second attachment means 22.2 functions as a spring-damper system, which has frequency-dependent properties. At slow motions, the system produces a relatively low stiffness, which does not affect the desired mechanical decoupling. At high excitation frequencies, which are likely to occur in highly dynamic applications, the system acts like a highly restoring damper, allowing relatively high natural frequencies in both the X and RX degrees of freedom.

[0050] Referring to Figure 5d, an alternative first stator 10.1a is configured similarly to the first stator 10.1. However, in contrast to the first stator 10.1, the alternative first stator 10.1a does not have the first attachment means (hereafter referred to as the third alternative). Furthermore, in contrast to the first stator 10.1, the upper surface 16.21a of the second segment 16.2a of the alternative first stator 10.1a is configured to be higher than the first pair of flexure joints 18.1a.

[0051] In a third alternative, the alternative first stator 10.1a itself (or the second segment 16.2a) forms the resting surface for the scale 12. This alternative first stator 10.1a is preferably made of steel.

[0052] Figures 6a-6c show the second stator 10.5 from various perspectives, and Figure 6d shows a perspective view of an exemplary alternative second stator 10.5a that can be part of the structure of Figure 1 in place of the second stator 10.5.

[0053] 6a and 9b, the second stator 10.5 includes a fifth segment 16.5 that secures the second stator 10.5 to the base 1, and sixth and seventh segments 16.6 and 16.7 that are connected to the fifth segment 16.5 and secure the second edge 12.21 of the scale 12 to the second stator 10.5. As shown in FIG. 6a, the second stator 10.5 includes a third pair of flexure joints 18.3 that are configured to allow movement of the sixth and seventh segments 16.6 and 16.7 in the lateral direction Y relative to the fifth segment 16.5.

[0054] As can be seen in Figure 6b, the third pair of flexure joints 18.3 includes two third leaf springs 18.31, 18.32 arranged opposite each other in the lateral direction Y. The third leaf springs 18.31, 18.32 are oriented parallel to the reference axis S. The third leaf springs 18.31, 18.32 each extend in the height direction Z (see Figure 6a).

[0055] 6a and 9b, the sixth segment 16.6 and the seventh segment 16.7 are fixed to at least the underside C of the scale 12 by a second material-bonding connection 20.2. This results in a second fixation of the underside of the scale 12 at the second position P2. The second material-bonding connection 20.2 is preferably a hardened adhesive connection. The adhesive surfaces of the sixth segment 16.6 and the seventh segment 16.7 for this adhesive connection (i.e., the second material-bonding connection 20.2) are shown hatched in FIG. 6a. The second material-bonding connection 20.2 comprises two adhesive ridges adjacent to the lateral surfaces of the scale 12 (see FIG. 9b).

[0056] As shown in Figure 6a, the second stator 10.5 is provided with a third adhesive means 22.3. The third adhesive means 22.3 is an elastically deformable material. The third adhesive means 22.3 is arranged on the upper surface 16.51 of the fifth segment 16.5 (i.e., the surface facing the scale 12) and in the transverse direction Y between the sixth segment 16.6 and the seventh segment 16.7. The third adhesive means 22.3 is in particular a sliding adhesive tape (fourth alternative) or a double-sided adhesive tape (fifth alternative).

[0057] If the third attachment means 22.3 is a double-sided adhesive tape, the adhesive tape serves to further secure the scale 12 to the second stator 10.5.

[0058] In a fourth alternative, the third attachment means 22.3 forms a mounting surface for the scale 12. The sliding adhesive tape consists, for example, of a resin layer and an adhesive layer. This adhesive layer secures the sliding adhesive tape to the second stator 10.5. Furthermore, this adhesive layer acts as a compensating element during shrinkage of the second material-bonding connection 20.2 (i.e., the preferably cured adhesive connection). This substantially prevents deformation of the scale 12, which improves the accuracy of the position measurement. In the fourth alternative, the third attachment means 22.3 also allows the scale 12 to be moved after it has been mounted on the second stator 10.5. This is advantageous when adjusting the position of the scale 12.

[0059] In the fifth alternative, the third attachment means 22.3 also forms a resting surface for the scale 12. As in the fourth alternative, the double-sided adhesive tape serves as an advantageous compensation element during shrinkage of the second material-bonding connection 20.2. In the fifth alternative, the third attachment means 22.3 also allows the scale 12 to be fixed in position immediately after being placed on the second stator 10.5. This allows for flexible assembly positions, in particular so-called overhead assembly.

[0060] Referring to Figure 6d, the alternative second stator 10.5a is configured similarly to the second stator 10.5. However, in contrast to the second stator 10.5, the alternative second stator 10.5a does not have the third attachment means (hereinafter, the sixth alternative). Furthermore, in contrast to the second stator 10.5, the upper surface 16.51a of the fifth segment 16.5a of the alternative second stator 10.5a is configured to be higher than the fifth segment 16.5a (see Figure 6d).

[0061] In a sixth alternative, the alternative second stator 10.5a itself (or the fifth segment 16.5a) forms the resting surface for the scale 12. This alternative second stator 10.5a is preferably made of steel.

[0062] The first to sixth alternatives provide a defined bonding gap for the first materially bonding connection 20.1 or the second materially bonding connection 20.2, respectively (see FIGS. 9a and 9b).

[0063] As shown in Figures 9a and 9b, the first stator 10.1 forms a first resting surface D1 for the first material-bonding connection 20.1, and the second stator 10.5 forms a second resting surface D2 for the second material-bonding connection 20.2. The first resting surface D1 and the second resting surface D2, together with the lateral surfaces of the scale 12, each function as a metering aid for the metering needle. This metering aid facilitates the application / metering of the adhesive.

[0064] As shown in Figure 9a, the lower surface C of the scale 12 is arranged above the first mounting surface D1 in the height direction (Z). Here, the height (Z position) of the lower surface C is set by the first attachment means 22.1 (or its thickness). A first gap is formed between the first mounting surface D1 and the lower surface C.

[0065] As shown in Figure 9b, the lower surface C of the scale 12 is disposed above the second mounting surface D2 in the height direction (Z). Here, the height (Z position) of the lower surface C is set by the third attachment means 22.3 (or its thickness). A second gap is formed between the second mounting surface D2 and the lower surface C.

[0066] The first gap and the second gap respectively form the defined bond gap described above (first alternative, second alternative, fourth alternative and fifth alternative).

[0067] In the third and sixth alternatives, as in the first, second, fourth and fifth alternatives, the height (Z position) of the lower surface C for forming each gap is set by the (higher configured) upper surface 16.21a (see Figure 5d) or surface 16.51a (see Figure 6d).

[0068] The first to third pairs of flexure joints 18.1 to 18.3 result in the bending states of the first stator 10.1 and the second stator 10.5 shown in FIGS. 7a, 7b, and 8. The previously shaded elements (glue surfaces and the first attachment means 22.1 or the third attachment means 22.3) have been omitted in FIGS. 7a, 7b, and 8. In FIG. 7a, the first stator 10.1 is shown in a first bending state, which corresponds to a decoupling in the degree of freedom: X_external release. In FIG. 7b, the first stator 10.1 is shown in a second bending state, which corresponds to a decoupling in the degree of freedom: Y_internal release. In FIG. 8, the second stator 10.5 is shown in a bending state, which corresponds to a decoupling in the degree of freedom: Y_internal release.

[0069] The first pair of flexure joints 18.1 has a first stiffness. The second pair of flexure joints 18.2 has a second stiffness. The second stiffness is preferably greater than the first stiffness, for example, 100 times greater. The third pair of flexure joints 18.3 has a third stiffness. The first and third stiffnesses are preferably the same magnitude.

[0070] The present invention has the following advantages, among others: The monolithic structure of the first stator 10.1 and the second stator 10.5, on the one hand, results in relatively low manufacturing costs, and, on the other hand, relatively simple adjustment / assembly of the structure. Furthermore, the monolithic structure results in a relatively high intrinsic stiffness of the structure. The symmetrical structure and positioning of the scale 12 with respect to the symmetry axis S allows for a symmetrical drift characteristic or symmetrical decoupling in the degree of freedom Y_internal, i.e., preferably a symmetrical movement of the first edge 12.11 or the second edge 12.21. Despite this symmetrical decoupling, a relatively high natural frequency (i.e., a substantially stationary fixation) is achieved in the degree of freedom Y_external. Furthermore, the present invention allows for decoupling in the degree of freedom X_external, at least at the first position P1. On the one hand, this allows for the entire structure to be as immune to temperature changes as possible. On the other hand, this allows for a relatively high intrinsic stiffness of the structure.

[0071] The present invention avoids stresses in the adhesive forming the first and second material-bonding connections 20.1, 20.2 caused by different thermal expansion coefficients and / or changes in ambient temperature. To this end, the shape, location, and number of adhesive surfaces (i.e., adhesive surfaces of the third and fourth segments 16.3, 16.4 or 16.3a, 16.4a and adhesive surfaces of the sixth and seventh segments 16.6, 16.7 or 16.6a, 16.7a) for the adhesive connections (i.e., first and second material-bonding connections 20.1, 20.2) are determined as shown in Figures 5a, 5b, 5d and 6a, 6b, 6d. This avoids failure of the adhesive connections (e.g., due to their rupture).

[0072] The invention is not limited to the photoelectric scanning principle: the measuring graduation 14 can in particular also be designed to be magnetically or inductively scannable.

Claims

1. A support (10); and a scale (12) arranged on the support (10), the scale (12) extending in the longitudinal direction (X), and the scale (12) having a measuring scale (14) arranged on a measuring scale surface (A1) for measuring a position in at least the longitudinal direction (X). A structure comprising: the support (10) comprises a plurality of individual segments (10.1 to 10.9), each of the individual segments (10.1 to 10.9) of the support (10) being configured as a stator for fixing the scale (12) to the support (10); The support (10) comprises a first stator (10.1) and a second stator (10.5), the first stator (10.1) being configured to hold a first cross-sectional portion (12.1) of the scale (12) at a first position (P1) so as to be freely movable in a longitudinal direction (X) relative to the support (10) and to hold the first cross-sectional portion (12.1) of the scale (12) rigidly to the support (10) in a lateral direction (Y) extending perpendicular to the longitudinal direction (X), and the second stator (10.5) being configured to hold a second cross-sectional portion (12.2) of the scale (12) at a second position (P2) different from the first position (P1) rigidly to the support (10) in both the longitudinal direction (X) and the lateral direction (Y). In the structure, The first and second stators (10.1, 10.5) allow the movement of the first and second edges (12.11, 12.21) of the scale (12), which are arranged at positions opposite each other in the transverse direction (Y), relative to the support (10) perpendicular to a reference axis (S), which extends parallel to the longitudinal direction (X), at the first and second positions (P1, P2), respectively. A structure characterized by being configured as follows.

2. 2. A structure according to claim 1, wherein said reference axis (S) is the axis of symmetry of said scale (12).

3. 3. A structure according to claim 1 or 2, wherein the first stator and the second stator (10.1, 10.5) are configured such that, in the first position and the second position (P1, P2), respectively, the first edge and the second edge (12.11, 12.21) of the scale (12) are allowed to move relative to the support (10) towards or away from the reference axis (S).

4. 2. The structure according to claim 1, wherein the first stator and the second stator (10.1, 10.5) are configured to allow symmetrical movement of the first edge and the second edge (12.11, 12.21) of the scale (12) about the reference axis (S) relative to the support (10) in the first position and the second position (P1, P2), respectively.

5. The first stator (10.1) has a first segment (16.1) for fixing the first stator (10.1) to the base (1), a second segment (16.2) connected to the first segment (16.1) for holding the scale (12), and third and fourth segments (16.3, 16.4) connected to the second segment (16.2) for fixing the first edge (12.11) of the scale (12) to the first stator (10.1). The first stator (10.1) has a first pair of flexure joints (18.1), and the first pair of flexure joints 2. The structure of claim 1, wherein the first stator (10.1) comprises a second pair of flexure joints (18.2) configured such that the flexure joints allow movement of the second segment (16.2) relative to the first segment (16.1) in a longitudinal direction (X), and the first stator (10.1) comprises a second pair of flexure joints (18.2) configured such that the flexure joints allow movement of the third and fourth segments (16.3, 16.4) relative to the second segment (16.2) in a transverse direction (Y).

6. 6. The structure according to claim 5, wherein the first pair of flexure joints (18.1) comprises two first leaf springs (18.11, 18.12) arranged opposite each other in a longitudinal direction (X), the first leaf springs (18.11, 18.12) being oriented perpendicular to the reference axis (S), and the second pair of flexure joints (18.2) comprises two second leaf springs (18.21, 18.22) arranged opposite each other in a transverse direction (Y), the second leaf springs (18.21, 18.22) being oriented parallel to the reference axis (S), the first and second leaf springs (18.11, 18.12; 18.21, 18.22) each extending in a height direction (Z) perpendicular to the measuring graduation surface (A1).

7. 7. A structure according to claim 5 or 6, wherein the third and fourth segments (16.3, 16.4) are fixed to at least the lower surface (C) of the scale (12) by first materially bonded connections (20.1).

8. 6. The structure according to claim 5, wherein the first stator (10.1) comprises first attachment means (22.1), which are elastically deformable means, and which are arranged on an upper surface of the second segment (16.2) and in the transverse direction (Y) between the third segment (16.3) and the fourth segment (16.4).

9. 6. The structure according to claim 5, wherein the first stator (10.1) comprises second attachment means (22.2) for fixing the first stator (10.1) to the base (1), the second attachment means (22.2) being vibration-damping means, the second attachment means (22.2) being arranged on the lower surface (16.22) of the second segment (16.2) and in the transverse direction (Y) between the third segment (16.3) and the fourth segment (16.4).

10. The second stator (10.5) has a fifth segment (16.5) that secures the second stator (10.5) to the base (1), and sixth and seventh segments (16.6, 16.7) that are connected to the fifth segment (16.5) and secure the second edge (12.21) of the scale (12) to the second stator (10.5). The second stator (10.5) has a third pair of flexure joints (18.3) that allow movement of the sixth and seventh segments (16.6, 16.7) in the lateral direction (Y) relative to the fifth segment (16.5).

2. The structure of claim 1, wherein the structure is configured as follows:

11. 11. The structure according to claim 10, wherein the third pair of flexure joints (18.3) comprises two third leaf springs (18.31, 18.32) arranged opposite each other in a transverse direction (Y), the third leaf springs (18.31, 18.32) being oriented parallel to the reference axis (S) and each of the third leaf springs (18.31, 18.32) extending in a height direction (Z) perpendicular to the measuring graduation surface (A1).

12. 12. The structure according to claim 10 or 11, wherein the sixth and seventh segments (16.6, 16.7) are fixed to at least the lower surface (C) of the scale (12) by second materially bonded connections (20.2).

13. 11. The structure according to claim 10, wherein the second stator (10.5) comprises third attachment means (22.3), the third attachment means (22.3) being elastically deformable means, the third attachment means (22.3) being arranged on an upper surface (16.51) of the fifth segment (16.5) and in the transverse direction (Y) between the sixth segment (16.6) and the seventh segment (16.7).

14. 2. A structure according to claim 1, wherein said first stator and said second stator (10.1, 10.5) are each integrally constructed.

15. 2. The structure of claim 1, wherein the first stator (10.1), the first cross-sectional portion (12.1) of the scale (12), the second stator (10.5), and the second cross-sectional portion (12.2) of the scale (12) are directly connected to each other.

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