Device for measuring forces and / or torques

Abstract

To provide an improved device for measuring force and / or torque applied to a six axis force torque sensor in particular, which does not need to be replaced as a whole in the case of overload in particular.SOLUTION: A first anchoring element 11, a second anchoring element 12 and a longitudinal element 15, wherein a force acting on the deformable body 10 or a torque acting on the deformable body 10 causes a deformation of the longitudinal element 15. In this case, a drive-side inlet 21 of the mechanical booster 20 is fixed to the deformation body 10 via a coupling element 30, a measurement object is arranged at an output-side outlet 22 of the mechanical booster 20, and deformation of the longitudinal element 15 causes movement of the measurement object. The movement of the measurement object can be detected by the sensing element, and the device is provided with an evaluation unit formed so as to evaluate a signal detected by at least one sensing element to calculate the force and / or torque acting between the two fixing elements 11, 12.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a device for measuring forces and / or torques according to the preamble of claim 1 . [Background technology]

[0002] Six-axis force-torque sensors are widely used in automation technology to determine acting forces and torques in all directions. For example, such sensors are used during automated joining or assembly of workpieces, during deburring, polishing, or grinding, during tactile measurement, and other applications. These sensors measure forces (F, or Fx, Fy, Fz) and torques (M, or Mx, My, Mz) acting in and around three coordinates (x, y, z). On the one hand, such sensors must be designed to be as rigid as possible so that they are not deformed by forces or torques. On the other hand, the resolution of the measurement signal must be as high as possible, which is usually not possible with rigid measurement systems, which only achieve small deformations due to their rigidity. Known sensors use, for example, strain gauges to determine forces and torques, which allow very small material strains to be measured. However, strain gauges are expensive. Furthermore, strain gauges require large signal amplification, which significantly increases the cost of such six-axis force-torque sensors. If the strain gauge is overloaded, the entire six-axis force torque sensor must be replaced, which also increases costs.

[0003] Patent document 1 discloses a device for measuring changes in length, the device comprising a first fixing element, a second fixing element, and at least one longitudinal element arranged between the two fixing elements, the at least one longitudinal element having a first end, a second end, and a length along a longitudinal direction, wherein a force acting parallel to the longitudinal direction causes a change in length of the longitudinal element; and a lever element having a first end, a second end, and a rotation point arranged transversely to the longitudinal direction, the lever element The device has a first lever arm having a first length between a rotation point and a first lever arm end, and a second lever arm having a second length between the rotation point and a second lever arm end, the second length being greater than the first length, a longitudinal element having a first end pivotably disposed on the first lever arm end of the first lever arm, and the second lever arm end of the second lever arm being connected to a measuring entity whose movement can be detected by a sensing element. This device also has the disadvantage that the entire device must be replaced in the event of an overload. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent Application Publication No. 102019135732 Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to provide an improved device for measuring forces and / or torques, in particular as applied to six-axis force-torque sensors, which device does not have to be replaced in its entirety, in particular in the case of overload. [Means for solving the problem]

[0006] This problem is solved according to the invention by a device for measuring forces and / or torques having the features of claim 1 of the appended claims. Advantageous embodiments and developments of the invention are set forth in the dependent claims.

[0007] A device for measuring forces and / or torques according to the present invention comprises a deformation body, the deformation body including a first fixing element, a second fixing element arranged at a distance from the first fixing element in one direction, and at least one longitudinal element arranged between the first fixing element and the second fixing element, the longitudinal element having a first end, a second end, and a length along a longitudinal direction, wherein a force or a torque acting on the deformation body causes a deformation of the longitudinal element, wherein a drive-side inlet of a mechanical booster is fixed to the deformation body via a coupling element, and a measurement embodiment is arranged at an output-side outlet of the mechanical booster, wherein the deformation of the longitudinal element causes a movement of the measurement embodiment, the movement of the measurement embodiment being detectable by a sensing element, and the device comprises an evaluation unit configured to evaluate a signal detected by the at least one sensing element and thereby calculate the force and / or torque acting between the two fixing elements.

[0008] The invention is based on the idea that if the deformable body absorbing the applied force or torque is separated by a coupling element from the component measuring the deformation, in particular from a mechanical booster that at least partially absorbs the deformation of the deformable body and increases it for detection by a sensing element, it is not necessary to replace the entire device damaged by an overload. This can reduce or avoid the effects of deformation on the components involved in measuring the deformation themselves. The modularization of the device 1 can minimize wear and breakdown of the individual components.

[0009] The coupling element allows only a portion of the force and / or a portion of the torque acting on the deformation body to be extracted, in particular in a direction approximately transverse to said one direction, and transmitted to the mechanical booster, so that the mechanical booster can be reliably protected against overload.

[0010] Preferably, the coupling element can be removably fixed, in particular to the deformation body and / or the mechanical booster. Such a structure makes it possible to separate the mechanical booster from the deformation body and fasten it to a new deformation body if the deformation body is damaged by overload. This allows replacement of the defective component and avoids the need to replace the entire device.

[0011] Advantageously, the connecting elements are formed as screws, pushable fastening pins, glued fastening pins or adhesive means, which can be manufactured, installed and replaced easily and at low cost.

[0012] In a particularly preferred embodiment of the invention, the mechanical booster is configured as a solid mechanism, which means a single part that is particularly flexible at certain points and, as a result, is able to perform movements without the presence of a typical joint. The flexible points are called solid joints.

[0013] Preferably, the solid mechanism is formed as one piece and has at least one solid joint, preferably several solid joints. The flexible point can be realized, for example, by a void in the material.

[0014] Advantageously, the solid mechanism is made of metal, preferably aluminium or steel. Preferably, the first fixing element has a disk or disk-ring shape with a first flat surface, and the second fixing element has a disk or disk-ring shape with a second flat surface, the first and second flat surfaces being parallel to each other. The disk-shaped structure of the fixing elements allows them to be easily fixed to relatively movable components for measuring forces and torques occurring between the components.

[0015] In a preferred embodiment of the present invention, the longitudinal direction of the longitudinal elements is arranged at an angle of 5° to 85°, preferably at an angle of 10° to 80°, preferably at an angle of 20° to 50°, particularly preferably at an angle of about 35°, relative to the direction Z. Such longitudinal elements arranged obliquely relative to the fixing element can increase the rigidity of the deformable body, and in so doing can absorb forces and / or torques more effectively than longitudinal elements arranged perpendicular to the fixing element.

[0016] In a particularly preferred embodiment, a plurality of longitudinal elements, in particular at least six, for example exactly six, are arranged between the first and second fixing elements, which allows the forces and torques acting between the two fixing elements to be determined in and around three axes and thereby allows the creation of a six-axis force-torque sensor.

[0017] Preferably, the deformation body is rotationally symmetric about a rotation angle of 120°. The symmetrical form contributes to improving the signal quality of the device. Particularly preferably, two longitudinal elements are arranged between the first and second fixed elements, each of which is assigned a mechanical booster, and the two mechanical boosters are realized by a single solid-state mechanism with two drive-side inlets and two output-side outlets. This arrangement is realized particularly by spatial proximity. The use of a solid-state mechanism realizing the two mechanical boosters improves the precision of the device.

[0018] In a particularly advantageous embodiment of the invention, the two longitudinal elements are arranged mirror-symmetrically, in particular with respect to an axis perpendicular to the two planes of the two fixing elements, and a mirror-symmetric composite solid-state mechanism is formed, comprising two mechanical boosters for the two longitudinal elements. The composite solid-state mechanism thus formed allows for sensitive displacement of the output outlet, while at the same time allowing for minimal parasitic movements along and around other spatial axes. This makes it possible to suppress dependencies between determining quantities, in particular forces and / or torques in different spatial directions.

[0019] Particularly preferably, two longitudinal elements and one composite solid-state mechanism form a group, with three such groups arranged between the first and second fixing elements, and the three groups being arranged, in particular, at an angular interval of 120° from each other. The use of three such groups, and thus six longitudinal elements and six mechanical multipliers, allows the force and torque acting between two fixing elements to be determined in three axial directions and around three axes. This allows the construction of a six-axis force-torque sensor in which the dependencies between the determined quantities, in particular the dependencies between the forces and / or torques in different spatial directions, are minimized as much as possible. The symmetrical configuration, on the one hand, can be manufactured in a simple manner, and, on the other hand, simplifies the evaluation of the determined signals.

[0020] Preferably, the sensing element and the evaluation unit are arranged on a circuit board, which is arranged in a recess of the first fixing element, in particular approximately parallel to the plane of the first fixing element. On the one hand, this arrangement allows for a compact design. On the other hand, if the deformation body is overloaded, for example if irreversible deformation occurs, the circuit board can be removed from the deformation body and installed in a new deformation body, provided that it is not damaged.

[0021] The sensing element is preferably configured as an optical, capacitive, inductive or magnetic sensing sensor, optical sensors in particular being particularly robust and capable of high-resolution sensing. Devices for measuring forces and / or torques based on measuring the deformation or length change of longitudinal elements are significantly affected by temperature changes, for example, when the material of the longitudinal elements expands at high temperatures. Advantageously, the device is equipped with at least one temperature sensor, preferably at least three temperature sensors, and particularly preferably six or eight temperature sensors, in order to take temperature changes into account when measuring the force and / or torque. The use of multiple temperature sensors, when they are distributed throughout the device, allows for more accurate temperature determination, for example, by averaging the temperatures measured by multiple temperature sensors. Preferably, the evaluation unit is configured to correct the force and / or torque acting between the two fixing elements as a function of temperature.

[0022] The present invention will now be described in detail with reference to the following drawings. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a perspective view of an embodiment of a device for measuring force and / or torque according to the invention, the device comprising a case, a deformable body with three composite solid-state mechanisms and an integrated circuit board, the case being removed in this view. [Figure 2] FIG. 2 is another perspective view of the device shown in FIG. [Figure 3] FIG. 2 is a perspective view of a variant of the device shown in FIG. 1; [Figure 4] FIG. 4 is a side view of the deformed body shown in FIG. 3. [Figure 5] 4 is another side view of the deformable body shown in FIG. 3. FIG. [Figure 6] FIG. 2 is a perspective view of the device shown in FIG. 1 without the case and with the two composite solid state mechanisms laterally removed. [Figure 7]2 is a perspective view of the device shown in FIG. 1 without the case, with one composite solid-state mechanism removed to the side and the other composite solid-state mechanism fixed. FIG. [Figure 8] 2 is a perspective view of a modified version of the device shown in FIG. 1, with the circuit board viewed obliquely from below, in partial cross section. FIG. [Figure 9] 2 is a perspective view, partly in section, of a variant of the device shown in FIG. 1, with the circuit board viewed obliquely from above. FIG. [Figure 10] FIG. 2 is a side view of one composite solid feature of the device shown in FIG. 1. [Figure 11] FIG. 11 is a perspective view of the output side outlet portion of the composite solid mechanism shown in FIG. 10. DETAILED DESCRIPTION OF THE INVENTION

[0024] 1 to 11 show various aspects of a first embodiment of a device 1 of the present invention for measuring a force F and / or a torque M, and components of this device 1. The same reference numbers indicate identical or functionally identical parts. In order to simplify the illustrations, not all reference numbers are used in all figures.

[0025] The device 1 includes a deformable body 10 shown separately in Figures 3 to 5. The deformable body 10 has a first fixing element 11 and a second fixing element arranged at a distance A from the first fixing element 11 in one direction Z. The first fixing element 11 may be formed in a disk shape or a disk-like ring shape having a first plane E1, and the second fixing element 12 may be formed in a disk shape or a disk-like ring shape having a second plane E2. In this case, the first plane E1 and the second plane E2 are arranged parallel to each other.

[0026] Between the first and second fixing elements 11, 12, at least one longitudinal element 15 having a first end 15a, a second end 15b and a length L is arranged along a longitudinal direction R. The first end 15a is in particular arranged on the first fixing element 11, and the second end 15b is arranged on the second fixing element 12. Each longitudinal element 15 in particular has its own longitudinal direction R. This means, in particular, that if there are several longitudinal elements 15, the longitudinal elements 15 do not necessarily have to be arranged entirely parallel to one another. The longitudinal direction R of the longitudinal elements 15 is arranged at an angle α of between 5° and 85°, preferably between 10° and 80°, more preferably between 20° and 50°, and particularly preferably at an angle α of about 35°, relative to the direction Z.

[0027] Between the first and second fixing elements 11, 12, preferably a number of longitudinal elements 15, six in this example, are arranged. The deformation body 10 can be formed rotationally symmetrically, in particular around a rotation angle of 120°.

[0028] The device 1 comprises at least one mechanical booster 20, which has a drive-side inlet 21 and an output-side outlet 22. The drive-side inlet 21 is arranged on the deformation body 10 via a coupling element 30, preferably in the vicinity of the longitudinal element 15 or on the longitudinal element 15 itself, while a measurement embodiment 25 is arranged on the output-side outlet 22.

[0029] The coupling element 30 can be removably fixed to either the deformation body 10 or the mechanical booster 20, or to both the deformation body 10 and the mechanical booster 20. The coupling element 30 can be formed as a screw, a pushable fastening pin, a glued fastening pin, or an adhesive. In this embodiment, the coupling element 30 is formed as a fastening pin, one end of which is inserted into the hole 15c of the deformation body 10. The hole 15c is arranged in a direction transverse to the direction Z of the deformation body 10 and can be arranged, for example, in the axial protrusion 11c of the first fixing element 11. The other end of the fastening pin is arranged in the mechanical booster 20, in particular, inserted into the hole 20c forming the drive-side inlet 21. The fastening pin can be pushed or glued into the two holes 15c, 20c, or, if the holes 15c, 20c have an appropriate internal thread, can be screwed in.

[0030] The mechanical booster 20 is particularly formed as a solid mechanism 50. The solid mechanism 50 is formed as a single part and has at least one solid joint, preferably several solid joints. The solid joints can be formed by suitable cavities in the material. The solid mechanism 50 is particularly made of metal, for example aluminum or steel.

[0031] The drive-side inlet 21 can also be formed in the solid-state device 50 by a hole 20c into which the coupling element 30 engages. The output-side outlet 22 has a measurement embodiment that can be arranged, for example, on a flat dish. In this case, the solid-state device 50 is arranged on the deformation body 10, in particular so that it is located between the first fixing element 11 and the second fixing element 12. In this case, the output-side outlet 21, in particular the measurement embodiment 25, faces towards the first fixing element 11.

[0032] As mentioned above, a plurality of longitudinal elements 15 (six in this embodiment) can be arranged between the first and second fixing elements 11, 12. Furthermore, a plurality of mechanical boosters 20 (six in this embodiment) can be arranged between the first and second fixing elements 11, 12. Each longitudinal element 15 is assigned a mechanical booster 20, which is achieved in particular by spatial proximity.

[0033] In this embodiment, the two mechanical boosters 20, designated 20-1 and 20-2 in FIG. 10 for ease of distinction, are realized by a single composite solid mechanism 60. This mechanism has two drive-side inlet sections 21-1 and 21-2 and two output-side outlet sections 22-1 and 22-2. The composite solid mechanism 60 is formed mirror-symmetrically with respect to the axis S, with one half forming the mechanical booster 20-1 and the other half forming the mechanical booster 20-2. Similarly, the two associated longitudinal elements 15, designated 15-1 and 15-2 in FIG. 6 for ease of explanation, are also arranged mirror-symmetrically with respect to the axis S. The axis S is arranged perpendicular to the planes E1 and D2 when the composite solid mechanism 60 is fixed to the deformable body 10. The two longitudinal elements 15-1, 15-2 and the composite solid-state mechanism 60 (including the two mechanical boosters 20-1, 20-2) form a group G. Preferably, the six longitudinal elements 15 and the six mechanical boosters 20 of the device 1 are grouped into three such groups G, with the groups G being arranged, in particular with their axes S, at an angular interval of 120° from each other.

[0034] Therefore, the deformable body 10 including the three composite solid mechanisms 60 is also formed rotationally symmetrically, particularly at a rotation angle of 120°. The movement of the measurement embodiment 25 is detectable by the sensing element 40. The sensing element 40 may be formed as an optical, capacitive, inductive, or magnetic detection sensor.

[0035] The device 1 comprises an evaluation unit 70, which is configured to evaluate the signal detected by the at least one sensing element 40 and to calculate therefrom the force F and / or torque M acting between the two fixing elements. By using six longitudinal elements 15 and six mechanical multipliers 20, it is possible in particular to form a six-axis force-torque sensor. To this end, the signals detected by the six sensing elements 40 are supplied to the evaluation unit 70, from which the forces Fx, Fy, Fz and torques Mx, My, Mz acting between the two fixing elements 11, 12 can be calculated by appropriate calibration.

[0036] The sensing element 40 and the evaluation unit 70 can be arranged on a circuit board 80, which is arranged in the recess 11a of the first fixing element 11, in particular approximately parallel to the plane E1 of the first fixing element 11. In this case, the sensing element 40 is arranged in particular on the side of the circuit board 80 facing the second fixing element 12. In particular, the first fixing element 11 has a cutout 11b through which the sensing element 40 can see the measurement embodiment 25 of the mechanical booster 20 (see Figures 8 and 9). Arranging the circuit board 80 in the recess 11a of the first fixing element 11 allows for a protected and compact arrangement.

[0037] The deformable body 10 can be placed in a pot-shaped case 100 such that the first fixing element 11 is fixed in the case 100, while the second fixing element 12 blocks the opening of the case 100. The case 100 can provide mechanical protection from damage and contamination, as well as protection from the ingress of foreign matter that may prevent the sensing element 40 from measuring.

[0038] The device 1 can be equipped with at least one temperature sensor 90, preferably at least three temperature sensors 90, particularly preferably six or eight temperature sensors 90. The temperature sensors 90 are arranged in particular distributed, preferably evenly distributed, on the device 1. The evaluation unit 70 detects and evaluates the temperature signals of the temperature sensors 90 and can, for example, calculate an average temperature from all temperature signals. Preferably, the evaluation unit 70 is configured to correct the force F and / or torque M acting between the fixing elements 11, 12 as a function of temperature.

[0039] A force F acting on the deformable body 10 or a torque M acting on the deformable body 10, due to the mechanical stiffness of the deformable body 10, causes an elastic deformation of the deformable body 10, in particular of one or more longitudinal elements 15. The mechanical coupling between the deformable body 10 and the mechanical booster 20 or the composite solid-state mechanism 60 by the coupling element 30 induces a displacement at the drive-side inlet 21 of the composite solid-state mechanism 60, which, taking into account the structure of the composite solid-state mechanism 60, is transferred to a displacement at the output-side outlet 22, thereby causing a movement of the measurement embodiment 25. In this case, the coupling element 30 particularly selectively transfers only the component of the force F acting on the deformable body 10 and / or the torque M acting on the deformable body 10, in particular in a direction substantially transverse to the one direction Z. In this case, the force flow is mainly transmitted via the deformable body 10, and the composite solid-state mechanism 60 is not involved in this. When the device 1 is overloaded, the deformable body 10 is primarily affected first, while all other components remain intact until the device 1 is completely damaged. The mechanical stiffness of the deformable body 10 determines the overall measuring range of the device 1, while the structure of the composite solid-state mechanism 60 determines the sensitivity and absolute displacement of the output outlet 22. However, parasitic movements along or around other spatial axes can be largely avoided. [Explanation of symbols]

[0040] 1 device 10 Transformation 11 First fixing element 11a Recessed part 11b Punching section 12 Secondary Fixing Element 15 Longitudinal elements 15-1 Longitudinal elements 15-2 Longitudinal elements 15a first end 15b second end 15c hole 20 Mechanical booster 20-1 Mechanical booster 20-2 Mechanical booster 20c hole 21 Drive side inlet 21-1 Drive side inlet 21-2 Drive side inlet 22 Output side outlet 22-1 Output side outlet 22-2 Output side outlet 25 Measurement Realization 30 Bonding Elements 40 Sensing element 50 Solid Mechanism 60 Composite Solid Mechanism 70 evaluation units 80 Circuit Board 90 Temperature Sensor 100 cases L length R Longitudinal direction Z one direction F force M Torque E1 First plane E2 Second plane A. Distance α angle S-axis G Group

Claims

1. A device (10) for measuring force (F) and / or torque (M), comprising: A deformable body (10) is provided, The deformable body (10) includes a first fixing element (11), a second fixing element (12) arranged spaced apart from the first fixing element (11) in one direction (Z), and at least one longitudinal element (15) arranged between the first fixing element (11) and the second fixing element (12), the longitudinal element (15) having a first end (15a), a second end (15b), and a length (L) along a longitudinal direction (R); A device (1) in which a force (F) acting on the deformable body (10) or a torque (M) acting on the deformable body (10) causes a deformation of the longitudinal element (15), A drive-side inlet (21) of a mechanical booster (20) is fixed to the deformation body (10) via a coupling element (30), and a measurement embodiment (25) is arranged at an output-side outlet (22) of the mechanical booster (20); a deformation of the longitudinal element (15) causes a movement of the measurement embodiment (25), the movement of the measurement embodiment (25) being detectable by a sensing element (40); The device (1) comprises an evaluation unit (70) configured to evaluate the signal detected by at least one of the sensing elements (40) and thereby calculate the force (F) and / or torque (M) acting between the two fixing elements (11, 12).

2. 2. The device (1) according to claim 1, characterized in that the coupling element (30) extracts only a portion of the force (F) acting on the deformation body (10) and / or only a portion of the torque (M) acting on the deformation body (10), in particular in a direction approximately transverse to the one direction (Z).

3. 3. Device (1) according to claim 1 or 2, characterized in that the coupling element (30) is releasably fixable.

4. Device (1) according to any one of claims 1 to 3, characterized in that the connecting element (30) is formed as a screw, a pushable fastening pin, a glued fastening pin or an adhesive means.

5. The device (1) according to any one of claims 1 to 4, characterized in that the mechanical booster (20) is formed as a solid-state mechanism (50).

6. 6. Device (1) according to claim 5, characterized in that the solid mechanism (50) is made in one piece and has at least one solid joint, preferably several solid joints.

7. 7. Device (1) according to claim 5 or 6, characterized in that the solid mechanism (50) is made of metal, preferably aluminum or steel.

8. The first fixing element (11) has a first flat surface (E1) and is formed in a disk shape or a disk-annular shape, The second fixing element (12) has a second flat surface (E2) and is formed in a disk shape or a disk-annular shape, The device (1) according to any one of claims 1 to 7, characterized in that the first plane (E1) and the second plane (E2) are arranged parallel to each other.

9. Device (1) according to any one of claims 1 to 8, characterized in that the longitudinal direction (R) of the longitudinal element (15) is arranged relative to the one direction (Z) at an angle (α) between 5° and 85°, preferably at an angle (α) between 10° and 80°, preferably at an angle (α) between 20° and 50°, particularly preferably at an angle (α) of about 35°.

10. The device (1) according to any one of claims 1 to 9, characterized in that a plurality of, in particular six, longitudinal elements (15) are arranged between the first fixing element (11) and the second fixing element (12).

11. two longitudinal elements (15-1, 15-2) are arranged between the first fixed element (11) and the second fixed element (12), each longitudinal element (15-1, 15-2) being assigned a mechanical booster (20-1, 20-2); The device (1) according to any one of claims 1 to 10, characterized in that the two mechanical boosters (20-1, 20-2) are realized together by a single composite solid mechanism (60), which has two drive-side inlet sections (21-1, 21-2) and two output-side outlet sections (22-1, 22-2).

12. the two longitudinal elements (15-1, 15-2) are arranged in mirror symmetry with respect to an axis (S) arranged perpendicular to the two planes (E1, E2), 12. The device (1) according to claim 11, characterized in that the composite solid mechanism (60) comprises the two mechanical multipliers (20-1, 20-2) for the two longitudinal elements (15-1, 15-2) and is formed mirror-symmetrically.

13. The two longitudinal elements (15-1, 15-2) and one composite solid mechanism (60) form one group (G), Three such groups (G) are arranged between the first fixing element (11) and the second fixing element (12), 13. Device (1) according to claim 11 or 12, characterized in that the three groups (G) are in particular arranged at angular intervals of 120° from each other.

14. The device (1) according to any one of claims 1 to 13, characterized in that the sensing element (40) and the evaluation unit (70) are arranged on a circuit board (80), which is arranged in a recess (11a) of the first fixing element (11), in particular approximately parallel to a plane (E1) of the first fixing element (11).

15. Device (1) according to any one of claims 1 to 14, characterized in that the sensing element (40) is formed as an optical, capacitive, inductive or magnetic sensing sensor.

16. The device (1) according to any one of claims 1 to 15, characterized in that the device (1) comprises at least one temperature sensor (90), preferably at least three temperature sensors (90), particularly preferably six or eight temperature sensors (90).

17. 17. The device (1) according to claim 1, wherein the evaluation unit (70) is configured to correct the force (F) and / or torque (M) acting between the two fixing elements (11, 12) as a function of temperature.

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