Assembly for position measurement

Abstract

The invention relates to an assembly for position measurement. The assembly comprises a support (10), a scale (12) arranged on the support (10) and a plurality of fixing elements (16) for fixing the scale (12) at the support (10). The scale (12) extends in a longitudinal direction (X). The scale (12) has a measurement scale (14) for position measurement at least in the longitudinal direction (X). The support (10) has a plurality of individual sections (10.1-10.7). The fixing elements (16) are arranged on the individual sections (10.1-10.7) of the support (10).

Description

Technical Field

[0001] This invention relates to a component according to the present invention. Background Technology

[0002] Document WO 2006 / 133753 A1 discloses an assembly for position measurement, comprising a support body and a plurality of fixing elements arranged along a scale and on both sides of the scale. Correspondingly arranged between the support body and the fixing elements are Festkoerpergelenk joints, which rotatably connect the fixing elements and thus the scale to the support body in the measurement direction X.

[0003] A known drawback of measurement assemblies is that the support body is constructed as a single piece. This results in relatively high manufacturing costs for both the support body and the measurement assembly. Furthermore, achieving thermal decoupling between the support body (or measurement assembly) and the substrate (e.g., the frame) is relatively complex, typically requiring structural measures such as the application of additional solid hinges. Thermal decoupling is a prerequisite for high accuracy in position measurements. Summary of the Invention

[0004] The purpose of this invention is to describe a component for position measurement that has a simple and cost-effective construction and is used to achieve accurate position measurement.

[0005] According to the invention, this objective is achieved by components according to the invention.

[0006] The component constructed according to the invention includes a support, a scale arranged on the support, and a plurality of fixing elements for securing the scale to the support. The scale extends longitudinally. The scale has measuring graduations for positional measurement, at least longitudinally. The support has a plurality of individual segments. The fixing elements are arranged on the individual segments of the support.

[0007] Preferably, a single section of the support is associated with one of the plurality of fixing elements or a pair of fixing elements arranged opposite each other in the transverse direction (which extends perpendicularly to the longitudinal direction).

[0008] It is advantageous if the individual sections of the support are arranged separately from each other in the longitudinal direction.

[0009] Furthermore, it is advantageous if the individual segments of the support are distributed longitudinally, for example, arranged at equal intervals.

[0010] Alternatively, the individual segments of the support can be arranged non-equidistantly. For example, the spacing between individual segments of the support near the fixed point (that is, the location where the scale is fixed) is greater than the spacing between individual segments of the support at the two free ends of the scale.

[0011] The fixing element preferably has multiple flexible hinges for (partial) thermal decoupling hinges between the bracket and the scale.

[0012] To fix the scale relative to the bracket position, the fixing element can be set in the form of an adhesive channel (Kleberaupe).

[0013] Individual sections of the support can also be referred to as discrete plates.

[0014] The measuring scale is preferably used for position measurement in the longitudinal direction (i.e., degree of freedom X) and in the transverse direction (i.e., degree of freedom Y). Alternatively, the measuring scale (associated with the corresponding probe unit) can be configured to enable position measurement in 6 degrees of freedom (i.e., degrees of freedom X, Y, Z, RX, RY, RZ).

[0015] The measurement scale can be, for example, an incremental scale (Inkrementalteilung). Alternatively, the measurement scale can be an absolute scale, for example, constructed as a pseudo-random code.

[0016] This invention achieves high repeatability of the linearity of the scale. This is particularly advantageous if the scale has measuring graduations for positional measurements in both the longitudinal and transverse directions. For this purpose, the measuring graduations comprise a plurality of graduation structures periodically arranged along a first measuring direction (the main measuring direction or the X direction) and a plurality of graduation structures periodically arranged along a second measuring direction (the Y direction). The first and second measuring directions extend perpendicularly to each other. The graduation structures specifically include graduation lines.

[0017] Advantageous construction options of the present invention are available from the specification. Attached Figure Description

[0018] Details and advantages of the components according to the invention will become apparent from the following description of embodiments with reference to the accompanying drawings. Wherein:

[0019] Figure 1 A perspective view of an assembly constructed according to the present invention is shown, which includes a support, a scale arranged on the support, and a plurality of fixing elements.

[0020] Figure 2 It shows the basis Figure 1 A top view of the components;

[0021] Figure 3a A perspective view of a single segment of the bracket is shown, with a first fixing element and a second fixing element.

[0022] Figure 3bIt shows the basis Figure 3a A top view of a single section of the support frame;

[0023] Figure 4a A perspective view of another individual section of the bracket is shown, featuring a third and a fourth fixing element; and

[0024] Figure 4b It shows the basis Figure 4a A top view of another individual section of the support. Detailed Implementation

[0025] Components that are identical or have the same function are given the same reference numerals in the figure.

[0026] An embodiment of the present invention will be described below. Figure 1 and Figure 2 The following describes the components constructed according to the invention. The components include a support 10, a scale 12 arranged on the support 10, and a plurality of fixing elements 16. The scale 12 extends in the longitudinal direction (main measurement direction) X and has measuring graduations 14 arranged in a measuring scale plane (i.e., the X / Y plane). The measuring graduations 14 are configured as photodetectable incremental graduations for high-precision position measurement in the longitudinal direction X and additionally in a second transverse direction Y perpendicular to this extension. The scale 12 is preferably constructed with a negligible coefficient of thermal expansion (especially less than 1.5 × 10⁻⁶ in the temperature range of 0°–50°C). -6 K -1 However, especially less than 0.1×10 -6 K -1 Materials with a coefficient of thermal expansion (α) are used. Such materials are glass or glass-ceramics (e.g., glass-ceramics (Zerodur)) or metals such as Invar alloys.

[0027] The support 10 is preferably made of a material with a diameter of approximately 10.5 × 10. -6 K -1 The steel has a high coefficient of thermal expansion.

[0028] The support 10 has multiple individual plate-shaped sections 10.1-10.7. The scale 12 has a rectangular cross-section with two opposing side surfaces (which extend accordingly in the longitudinal X direction) 18.1, 18.2 (see reference). Figure 2 ).

[0029] The fixing element 16 is used to fix the scale 12 to the bracket 10. The fixing element 16 includes a first set of fixing elements 16.11-16.71 and a second set of fixing elements 16.12-16.72. The fixing elements 16.11-16.71 and 16.12-16.72 are arranged at two opposing side surfaces 18.1 and 18.2 of the scale 12 (see reference). Figure 2 ). For example in Figure 1 As shown, the fixing element 16 is arranged on a single section 10.1-10.7 of the bracket 10.

[0030] exist Figure 1 The components shown are arranged on a base 1 (e.g., a frame). Bolts 2 are provided to secure the components to the base 1. Bolts 2 extend through individual sections 10.1-10.7 until they enter the base 1. The base 1 is, for example, made of granite.

[0031] The multi-piece support structure (i.e., support 10) is achieved using the components according to the invention. This multi-piece construction is advantageous compared to the single-piece construction according to the prior art, making the manufacture of the support structure and thus the components relatively cost-effective. Furthermore, the multi-piece construction has the advantage of enabling thermal decoupling between the support 10 and the base 1 in a simple manner. In particular, additional structural measures, such as the application of additional flexural joints, can be omitted here.

[0032] Advantageously, the individual segments (discrete plates) 10.1-10.7 of the support 10 are relatively small and can be easily moved with the base 1 at approximately any location (i.e., locally at the corresponding X position). Thus, compared with the prior art, the aforementioned thermal decoupling is achieved without the application of additional structural measures.

[0033] Between the individual sections 10.1-10.7 of the bracket 10, there are additional sections 11.1-11.6 (so-called intermediate sections) of the bracket 10. The intermediate sections 11.1-11.6 are fixed to the base 1 by bolts 4 and are used to support the scale 12 in the height direction (i.e., the Z direction). In this regard, the intermediate sections 11.1-11.6 are configured to rigidly bear the scale 12 at the bracket 10 in the height direction Z via attachment devices (Haftmittel) at an intermediate position (i.e., between the individual sections 10.1-10.7 of the bracket 10) and are thus rigidly connected to the base 1. The intermediate sections 11.1-11.6 may also be omitted.

[0034] about Figure 1 Each segment 10.1-10.7 of the bracket 10 is associated with a pair of fixing elements 16.11, 16.12-16.71, 16.72 arranged opposite to each other in the transverse Y direction among the plurality of fixing elements 16. In particular, the pair of fixing elements 16.11, 16.12-16.71, 16.72 are arranged on the corresponding individual segment 10.1-10.7 of the bracket 10.

[0035] Alternatively, a single segment 10.1-10.7 of the bracket 10 may be associated with only one of the plurality of fixing elements 16 (e.g., fixing elements 16.11-16.71 or fixing elements 16.12-16.72).

[0036] As in Figure 1 As shown, the individual segments 10.1-10.7 of the support 10 are arranged separately from each other in the longitudinal direction X. Furthermore, the individual segments 10.1-10.7 of the support 10 are distributed, particularly equidistant, in the longitudinal direction X. Here, the spacing between the individual segments 10.1-10.7 of the support 10 is, for example, 100 mm.

[0037] exist Figure 1 The fixing element 16 shown has a first fixing element 16.11 disposed on a first side surface 18.1 of the scale 12 and a second fixing element 16.12 disposed on a second side surface 18.2 of the scale 12. The first fixing element 16.11 and the second fixing element 16.12 are arranged opposite to each other in the transverse Y direction. The following embodiments are similarly applicable to the paired fixing elements 16.21, 16.22-16.71, 16.72 (except for 16.41, 16.42).

[0038] The first fixing element 16.11 is configured at position P1 (refer to...) Figure 3b The scale 12 is freely movable relative to the support 10 in the longitudinal direction X. Furthermore, the first fixing element 16.11 is configured to rigidly support the scale 12 at the support 10 in the transverse direction Y. In this regard, the first fixing element 16.11 is specifically configured as a flexural hinge.

[0039] about Figure 3b The first fixing element 16.11 has a first section 20.1 fixed to the first side surface 18.1 of the scale 12 by a material-fit connection. Furthermore, the first fixing element 16.11 has a second section 20.2 fixed to the upper surface 22 of the section 10.1 associated with the first fixing element 16.11 in the bracket 10, specifically in sections 10.1-10.7, by a material-fit connection (see reference). Figure 3a and Figure 3b The connection of materials, especially adhesive bonding.

[0040] The second fixing element 16.12 is configured to support the scale 12 in the longitudinal direction X relative to the bracket 10 at the first position P1. Furthermore, the second fixing element 16.12 is configured to rigidly support the scale 12 at the bracket 10 in the transverse direction Y. In this regard, the second fixing element 16.12 is specifically configured as a flexural hinge.

[0041] The second fixing element 16.12 is similar to the first fixing element 16.11 and is connected to the scale 12 and the section 10.1 of the bracket 10.

[0042] about Figure 3a The assembly has a first attachment device 24.1 for securing the scale 12 to the bracket 10. The first attachment device 24.1 is disposed on the upper surface 22 of a section 10.1 of the bracket 10 on one side and between the first fixing element 16.11 and the second fixing element 16.12 on the other side. The first attachment device 24.1 is constructed in a strip shape and extends generally in the transverse Y direction. For example, the first attachment device 24.1 has a strip of double-sided tape, especially transfer tape.

[0043] The first attachment device 24.1 is correspondingly arranged on each of the sections 10.1-10.7 of the bracket 10 (except for 10.4).

[0044] exist Figure 1 The fixing element 16 shown in the figure also has a third fixing element 16.41 arranged on the first side surface 18.1 of the scale 12 and a fourth fixing element 16.42 arranged on the second side surface 18.2 of the scale 12. The third fixing element 16.41 and the fourth fixing element 16.42 are arranged opposite to each other in the transverse Y direction. The paired fixing elements 16.41 and 16.42 are associated with or arranged on the section 10.4 of the bracket 10.

[0045] The third fixing element 16.41 is configured to be in a second position P2, different from the first position P1 (see reference). Figure 4b The scale 12 is rigidly supported at the support 10 in the longitudinal direction (X) and the transverse direction (Y). The fourth fixing element 16.42 is configured to rigidly support the scale 12 at the support 10 in the longitudinal direction (X) and the transverse direction (Y) at the second position (P2). For example, the third fixing element 16.41 and the fourth fixing element 16.42 respectively have adhesive channels, especially fillet welds, for connecting the scale 12 to the section 10.4 of the support 10.

[0046] about Figure 4aThe component further includes a second attachment device 24.2 and a third attachment device 24.3 for fixing the scale 12 to the bracket 10. The second attachment device 24.2 and the third attachment device 24.3 are arranged on the upper surface of section 10.4 of the bracket 10 on one side and between the third fixing element 16.41 and the fourth fixing element 16.42 on the other. The second attachment device 24.2 and the third attachment device 24.3 are respectively constructed in a strip shape and extend generally in the longitudinal direction X. For example, the second attachment device 24.2 and the third attachment device 24.3 respectively have strips of double-sided adhesive tape, especially adjustable adhesive tape.

[0047] The first to third attachment devices 24.1-24.3 are used to support the fixation of the scale 12 by the first to fourth fixing elements 16.11, 16.12, 16.41, 16.42. This achieves a particularly stable and reliable construction of the assembly.

[0048] In addition, the first to third attachment devices 24.1-24.3 are used to decouple the scale 12 from the bracket 10 to prevent frictional effects (or the generation of limited shear force).

[0049] For example, the first to third attachment devices 24.1-24.3 respectively have strips with double-sided adhesive tape of 10 mm width.

[0050] Instead of the aforementioned mixing tape, very soft adhesives or liquid mixing tapes with mixing balls can also be used.

[0051] The third and fourth fixing elements 16.41 and 16.42 may alternatively be configured such that they, at the second position P2, rigidly in the longitudinal direction X but flexibly (softly) in the transverse direction Y, carry or connect to the scale 12 at the bracket 10. Such a connection is disclosed in particular in document EP 3 026 389 A1.

[0052] The advantage of this invention is that the scale 12 is connected to the base 1 in the Y direction without significant lateral movement and flexural deformation under lateral force (e.g., lateral acceleration) via the fixing element 16. This is particularly advantageous for measuring the position of the scale 14 in both the longitudinal (degree of freedom X) and lateral (degree of freedom Y) directions.

[0053] The substrate 1 is preferably made of a material with a smaller coefficient of thermal expansion than that of the support 10.

[0054] This invention is not limited to the principle of photoelectric detection. The measuring scale 14 can also be constructed in a magnetically or inductively detectable manner.

Claims

1. A component for position measurement, comprising: Frame (10), A scale (12) is arranged on the bracket (10), wherein, The scale (12) extends in the longitudinal direction (X), and wherein the scale (12) has measuring graduations (14) for position measurement at least in the longitudinal direction (X), and Multiple fixing elements (16) are used to fix the scale (12) to the bracket (10). The bracket (10) has multiple individual sections (10.1-10.7) configured as separate plates, wherein the fixing element (16) is arranged on the individual sections (10.1-10.7) of the bracket (10), and wherein an intermediate section (11.1-11.6) of the bracket (10) without the fixing element (16) is arranged between the individual sections (10.1-10.7) of the bracket (10), the intermediate section (11.1-11.6) being used to support the scale (12) in the height direction.

2. The component according to claim 1, wherein, Each segment (10.1-10.7) of the bracket (10) is associated with one of the plurality of fixing elements (16) or a pair of fixing elements (16.11, 16.12-16.71, 16.72) arranged opposite each other in the transverse (Y) direction perpendicular to the longitudinal (X) direction.

3. The component according to claim 1, wherein, The individual sections (10.1-10.7) of the support (10) are arranged in a longitudinal (X) direction.

4. The component according to claim 3, wherein, The individual sections (10.1-10.7) of the support (10) are arranged equidistantly in the longitudinal direction (X).

5. The component according to any one of claims 1-4, wherein, The fixing element (16) has at least one first fixing element (16.11) arranged on the first side surface (18.1) extending in the longitudinal (X) direction of the scale (12).

6. The component according to claim 5, wherein, The first fixing element (16.11) is configured to carry the scale (12) in the longitudinal (X) direction at a first position (P1) relative to the bracket (10).

7. The component according to claim 5, wherein, The first fixing element (16.11) is configured to rigidly carry the scale (12) at the bracket (10) in a transverse (Y) direction that extends perpendicular to the longitudinal direction (X).

8. The component according to claim 5, wherein, The first fixing element (16.11) has a first section (20.1) fixed to the first side surface (18.1) of the scale (12) by a material fit connection.

9. The component according to claim 5, wherein, The first fixing element (16.11) has a second section (20.2), wherein the second section (20.2) is fixed to the upper surface (22) of the section (10.1) of the individual sections (10.1-10.7) of the bracket (10) by a material-fit connection.

10. The component according to claim 8 or 9, wherein, The connection between the materials is an adhesive connection.

11. The component according to claim 5, wherein, The fixing element (16) has a second fixing element (16.12) disposed on a second side surface (18.2) extending in the longitudinal direction (X) of the scale (12), wherein the first fixing element (16.11) and the second fixing element (16.12) are disposed opposite to each other in the transverse direction (Y) extending perpendicular to the longitudinal direction (X).

12. The component of claim 11, wherein, The first fixing element (16.11) and the second fixing element (16.12) respectively have a flexural hinge portion.

13. The component according to claim 11 or 12, wherein, The component has at least one first attachment device (24.1) for securing the scale (12) to the bracket (10), wherein the first attachment device (24.1) is disposed on the upper surface (22) of the segment (10.1) associated with the first fixing element (16.11) and the second fixing element (16.12) in a single segment (10.1-10.7) of the bracket (10) and between the first fixing element (16.11) and the second fixing element (16.12).

14. The component of claim 13, wherein, The first attachment device (24.1) is constructed in a strip shape and extends in a transverse (Y) direction perpendicular to the longitudinal direction (X).

15. The component according to claim 6, wherein, The fixing element (16) has at least one third fixing element (16.41) disposed on a first side surface (18.1) of the scale (12), wherein the third fixing element (16.41) is configured to rigidly carry the scale (12) at the bracket (10) in the longitudinal direction (X) and in the transverse direction (Y) extending perpendicular to the longitudinal direction (X) at a second position (P2) different from the first position (P1).

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