Actuator device and method

Abstract

The invention relates to an actuator device and a method for industrial automation, in particular a pneumatic pivot drive or a pneumatic gripper, comprising a magnetic field sensor device and a drive device for carrying out a drive movement, the drive device having a rotational movement part comprising a first magnetic element, the drive device comprises a rotary motion part, a linear motion part which is coupled with the rotary motion part in motion and is provided with a second magnetic element, and the rotary position of the linear motion part relative to the magnetic field sensor device is changed in a rotary position-angle range of more than one circle in a driving motion process. The actuator device has a first magnetic element and a second magnetic element, and a linear movement relative to the magnetic field sensor device during a drive movement, the magnetic field sensor device being configured to detect a magnetic field of the first and second magnetic elements, and an evaluation unit, the evaluation unit is configured to determine a single and unambiguous rotational position of the rotational moving part with respect to the rotational position-angle range on the basis of the detected magnetic field.

Description

Technical Field

[0001] This invention relates to an actuator device for industrial automation, particularly a pneumatic pivot drive or pneumatic gripper, comprising a magnetic field sensor device and a drive device for performing a drive motion, wherein the drive device has a rotary motion component including a first magnetic element and changing its rotational position relative to the magnetic field sensor device within a rotational position-angle range of more than one revolution during the drive motion, wherein the drive device further comprises a linear motion component kinematically coupled to the rotary motion component. Background Technology

[0002] For example, the linear motion component is a pneumatically actuated piston assembly, which, together with the rotary motion component, forms a rack and pinion drive, particularly a pinion drive. Actuators with a rotational position-angle range exceeding one revolution can also be called multi-turn actuators. Summary of the Invention

[0003] The object of the present invention is to determine a single, definite rotational position of a rotating motion component with respect to a rotational position-angle range, that is, relative to an angular range that includes more than one revolution (i.e., more than 360 degrees).

[0004] This objective is achieved by the actuator device according to claim 1. The actuator device has a second magnetic element that moves linearly relative to a magnetic field sensor device during driven motion, wherein the magnetic field sensor device is configured to detect the magnetic fields of the first and second magnetic elements, and the actuator device further has an evaluation unit configured to determine a single, definite rotational position of the rotating motion component with respect to a rotational position-angle range based on the detected magnetic field.

[0005] "The magnetic field sensor device detects the magnetic field of the first magnetic element and the second magnetic element" specifically means that the magnetic field of the first magnetic element and the magnetic field of the second magnetic element are included in the magnetic field detection performed by the magnetic field sensor device, that is, for example, the magnetic field sensor device detects the total magnetic field generated by the superposition of the magnetic fields of the first magnetic element and the second magnetic element.

[0006] The linear motion of the second magnetic element relative to the magnetic field sensor device causes a change in the magnetic field detected by the second magnetic element at the location of the magnetic field sensor device. Since the rotating and linear motion components are kinematically coupled, and the linear motion of the linear motion component is thus related to the rotational motion of the rotating motion component, the rotational motion component's current revolution can be identified based on the magnetic field detected by the second magnetic element. Therefore, a single, definite rotational position of the rotating motion component with respect to the rotational position-angle range can be determined.

[0007] Therefore, preferably, the first magnetic element rotates, and the second magnetic element moves linearly accordingly, wherein the magnetic fields of the two magnetic elements are superimposed and, in particular, detected by a single sensor element, thereby achieving a clear correlation between the sensor signal of the sensor element and the system state of the drive device throughout the entire range of motion—that is, particularly the entire range of rotational position-angle. In this manner, the evaluation unit is preferably able to directly determine a single, definite rotational position when the actuator device is turned on, thus achieving true power-on of the multi-turn actuator mechanism.

[0008] Advantageous improvements are the subject of the dependent claims.

[0009] The present invention also relates to a method for operating an actuator device, comprising the following steps:

[0010] - Execute driving motion;

[0011] – Detecting the magnetic fields of the first and second magnetic elements using a magnetic field sensor device; and

[0012] -Based on the detected magnetic field, the single, specific rotational position is determined using an evaluation unit. Attached Figure Description

[0013] Other exemplary details and exemplary embodiments will be described below with reference to the accompanying drawings.

[0014] Figure 1 A schematic diagram of the actuator device is shown;

[0015] Figure 2 The graphs showing the first and second magnetic field values ​​are shown.

[0016] Figure 3 Another graph showing the first and second magnetic field values ​​is presented; and

[0017] Figure 4 Another graph showing the first and second magnetic field values ​​is presented. Detailed Implementation

[0018] Figure 1 An exemplary design of an actuator device 1 for industrial automation is shown. Purely exemplary, the actuator device 1 is designed as a pneumatic actuator device.

[0019] The actuator device 1 includes a drive mechanism for performing the drive motion 3. The drive mechanism includes a rotary motion component 4 and at least one linear motion component 6 that is motionally coupled to the rotary motion component 4. The linear motion component 6 is motionally coupled to the rotary motion component 4 such that the rotary motion component 4 performs a rotary motion while the linear motion component 6 performs a linear motion. The drive motion 3 is, for example, the linear motion of the linear motion component 6. Alternatively, the drive motion can be the rotational motion of the rotary motion component 4 or other motions.

[0020] Linear motion, for example, occurs along the x-direction. Rotational motion, for example, occurs about an axis of rotation, particularly along the z-direction. The z-direction is perpendicular to the plane of the drawing. The y-direction will also be mentioned below. The x, y, and z directions are orthogonal to each other.

[0021] For example, the drive unit is designed as a rack and pinion drive, particularly a pinion drive. The rotary motion component 4 includes a gear 17, and the linear motion component 6 includes a rack 8 that meshes with the gear 17.

[0022] Preferably, the drive device is designed as a pneumatic drive device. The linear motion component 6 is designed, for example, as a piston assembly. The actuator device 1 includes at least one pressure chamber 9 that pneumatically acts on the linear motion component 6 and causes a driving motion through its pneumatic actuation, thereby causing linear motion and / or rotational motion. For example, the actuator device 1 has two pressure chambers 9 that pneumatically act on the linear motion component 6.

[0023] Purely by way of example, the drive unit has another linear motion component 10, which is suitably also designed as a piston assembly and has another rack 11 that meshes with the gear 17. This other linear motion component 10 may be driven, for example, by means of at least one other pressure chamber 12, and in particular by means of two other pressure chambers 12.

[0024] For example, actuator device 1 has one or more wall structures 13, which limit one or more pressure chambers 9, 12.

[0025] Actuator device 1 includes magnetic field sensor device 2, such as Figure 1 As shown by the dashed line. This magnetic field sensor device is preferably designed as a magnetic field sensor element, particularly a three-dimensional Hall sensor. The magnetic field sensor device 2 is disposed within (or on) the actuator device 1, making it fixed relative to the rotating motion component 4 and / or relative to the linear motion component 6. Therefore, the magnetic field sensor device 2 does not move during the rotational motion of the rotating motion component 4 or the linear motion of the linear motion component 6.

[0026] The rotating component 4 includes a first magnetic element 5, which is designed, for example, as a ring magnet. The first magnetic element 5 is a permanent magnet. The ring magnet is oriented particularly coaxially with the axis of rotation of the rotating component 4. The first magnetic element 5 is particularly magnetized radially. For example, the magnetization direction of the first magnetic element 5 is perpendicular to the axis of rotation of the rotating component 4, and therefore lies particularly in the xy plane.

[0027] During the driving motion 3, the rotating motion component 4 (and thus the first magnetic element 5) changes its rotational position relative to the magnetic field sensor device 2 within a rotational position-angle range of more than one revolution. Therefore, the rotational position-angle range extends from 0 degrees to more than 360 degrees, for example from 0 degrees to 720 degrees, or it could be larger. Adjacent sub-ranges of the rotational position-angle range (each sub-range being exactly 360 degrees) should also be referred to as "revolutions" and identified by consecutive revolution numbering, where the first sub-range (i.e., the range from 0 degrees to 360 degrees) is numbered "0". The last sub-range can also be less than 360 degrees, especially when the rotational position-angle range is not an integer multiple of 360 degrees.

[0028] The linear motion component 6 has a second magnetic element 7. The second magnetic element 7 is a permanent magnet. During the driving motion, the linear motion component 6 (and consequently the second magnetic element 7) moves linearly relative to the magnetic field sensor device 2. The second magnetic element 7 can be designed as a ring magnet, for example, and its ring axis is preferably oriented along the axial direction of the linear motion. Preferably, the second magnetic element 7 is axially magnetized. In particular, the magnetization direction of the second magnetic element 7 is the x-direction. Preferably, the magnetization direction of the second magnetic element 7 is orthogonal to the magnetization direction of the first magnetic element 4.

[0029] As described above, the actuator device 1 can be designed, for example, as a pneumatic pivot actuator or a pneumatic gripper. When designed as a pneumatic pivot actuator, it is suitable to drive the shaft by means of a rotary motion component 4, or to design the rotary motion component 4 as a driven shaft. Pneumatic rotary actuators are used, for example, to actuate valves, particularly process valves. Preferably, an assembly including a valve and an actuator device 1 is provided, wherein the actuator device 1 is used to actuate the valve by a driving motion. When designed as a pneumatic gripper, a gripping section, particularly a gripping finger, is provided on the linear motion element 6, which can perform a gripping motion by a driving motion.

[0030] The magnetic field sensor device 2 is designed to detect the magnetic fields of a first magnetic element 5 and a second magnetic element 7. The magnetic field of the first magnetic element 5 is also referred to as the first magnetic field, and the magnetic field of the second magnetic element 7 is also referred to as the second magnetic field. These two magnetic fields are superimposed in the magnetic field sensor device 2, particularly within the magnetic field sensor element. Preferably, the magnetic field sensor element is configured to measure the magnetic field strength of the superimposed magnetic field of the first magnetic element 5 and the second magnetic element 7 (within the magnetic field sensor element), particularly in multiple spatial directions, for example, in three spatial directions, particularly orthogonal to each other. In this way, the magnetic fields of the magnetic elements 5 and 6 can be detected.

[0031] The actuator device has an evaluation unit 14, which is designed, for example, as a computer unit, particularly a microcontroller. The evaluation unit 14 is communicatively connected to the magnetic field sensor device 2 and receives one or more magnetic field sensor signals from the magnetic field sensor device 2. According to alternative designs, the evaluation unit may be integrated into the magnetic field sensor device, or the magnetic field sensor device may be integrated into the evaluation unit.

[0032] Evaluation unit 14 is configured to determine a single, defined rotational position of the rotating motion component 4 with respect to a rotational position-angle range based on the detected magnetic field. A single, defined rotational position refers to a rotational position that corresponds to only one unique angle within the rotational position-angle range. As mentioned above, the rotational position-angle range extends beyond one full rotation, i.e., more than 360 degrees. A single, defined rotational position can also be referred to as an absolute rotational angle.

[0033] Evaluation unit 14 suitably provides rotational position information, such as a numerical value, that includes a single, defined rotational position. Evaluation unit 14 may optionally output the rotational position information, such as an output signal.

[0034] The term "direction of rotation" refers to the angle of rotation of the rotating moving part 4 within one revolution, that is, the angle of rotation within the range of 0 to 360 degrees. For each revolution, the direction of rotation begins at 0 degrees and ends at 360 degrees. The direction of rotation relative to the rotational position-angle range (including multiple revolutions) is not fixed, because the same direction of rotation may exist in different revolutions.

[0035] Preferably, the evaluation unit 14 is configured to provide (in particular determine) a first magnetic field value and a second magnetic field value using the magnetic field sensor device 2. The first magnetic field value depends on the rotation direction of the first magnetic element 5. For example, the first magnetic field value indicates the rotation direction of the first magnetic element 5. Specifically, the magnetic field sensor device 2 measures the magnetic field strength in the x-direction and the magnetic field strength in the y-direction, and the evaluation unit 14 calculates the rotation direction of the first magnetic element 5 (about a rotation axis extending along the z-direction) based on these magnetic field strengths.

[0036] The second magnetic field value depends on the distance between the second magnetic element 7 and the magnetic field sensor device 2. Optionally, the second magnetic field value indicates the distance between the second magnetic element 7 and the magnetic field sensor device 2. For example, the second magnetic field value is the magnetic field strength, particularly in the z-direction.

[0037] Preferably, the first magnetic field value is based on (especially only) a first magnetic field component (measured by the magnetic field sensor device 2), such as the magnetic field strength in the x-direction, and a second magnetic field component (measured by the magnetic field sensor device 2), such as the magnetic field strength in the y-direction. Preferably, the second magnetic field value is based on (especially only) a third magnetic field component (measured by the magnetic field sensor device 2), such as the magnetic field strength in the z-direction. The first, second, and third magnetic field components are preferably orthogonal to each other. This specifically means that the spatial directions in which these magnetic field components are measured are orthogonal to each other. Preferably, the first and second magnetic field components are perpendicular to the rotation axis of the rotating motion component 4 (i.e., perpendicular to the z-direction), and / or the third magnetic field component is oriented axially along the rotation axis of the rotating motion component (i.e., along the z-direction).

[0038] Preferably, the evaluation unit 14 is configured to determine a single, definite rotational position of the rotating motion component 4 based on a first magnetic field value and a second magnetic field value.

[0039] For example, evaluation unit 14 is configured to provide (in particular determine) the rotation direction of the rotating motion component 4 based on a detected first magnetic field value, and to determine the number of revolutions of the rotating motion component 4 based on a detected second magnetic field value. The number of revolutions indicates which revolution within the rotational position-angle range the rotating motion component 4 is located on. Evaluation unit 14 is configured to determine a single, specific rotational position based on the rotation direction and the number of revolutions.

[0040] refer to Figure 2 The view shown will explain an exemplary practice for determining a single, specific rotational position.

[0041] The rotational position-angle range is plotted on the horizontal axis, comprising, for example, approximately 2.5 revolutions: a first revolution U0, a second revolution U1, and a third revolution U2. A first curve 15 representing the first magnetic field value (e.g., the direction of rotation) and a second curve 16 representing the second magnetic field value are plotted on the vertical axis. The first curve 15 repeats periodically for each (complete) revolution, particularly from 0 degrees to 360 degrees. The second curve 16 increases monotonically throughout the rotational position-angle range. Suitably, the second magnetic field value primarily represents the magnetic field strength provided by the second magnetic element 7. For example, as the rotational position of the rotating motion element 4 increases, the second magnetic element 7 moves (particularly monotonically) toward the magnetic field sensor device 2, preferably, throughout the rotational position-angle range.

[0042] Evaluation unit 14 suitably has corresponding transition thresholds S1, S2 for each transition from one circle to the next, the thresholds corresponding to the corresponding second magnetic field value when the transition occurs.

[0043] The transition from one lap to the next is also called a lap-transition.

[0044] The evaluation unit 14 compares the second magnetic field value with one (or more) transition thresholds S1 and S2 to determine which revolution the rotating component 4 is in and provides the corresponding number of revolutions. If the second magnetic field value is less than the first transition threshold S1, the evaluation unit 14 provides a number of revolutions of "0". If the second magnetic field value is greater than the first transition threshold S1 and less than the second transition threshold S2, the evaluation unit 14 provides a number of revolutions of "1". If the second magnetic field value is greater than the second transition threshold S2, the evaluation unit 14 provides a number of revolutions of "2".

[0045] Evaluation unit 14 multiplies the provided number of rotations by 360 degrees and adds the direction of rotation (in degrees) to the result in order to calculate a single, specific rotational position.

[0046] According to the preferred design, the third magnetic field component is smaller, and particularly significantly smaller, than the first and second magnetic field components. This reduces the potential interference of the second magnetic element 7 on the rotation direction measurement. If the third magnetic field component is too small, noise may appear in the detected third magnetic field component. (Reference) Figure 2 The following section will explain a scheme, in particular, to avoid such noise from causing errors in the determination of a specific rotational position.

[0047] Preferably, the evaluation unit 14 is configured to determine the number of revolutions while taking into account the first magnetic field value. For example, the evaluation unit 14 is configured to determine two successive candidate values ​​for the number of revolutions based on the detected second magnetic field value, and to select one of the two candidate values ​​as the number of revolutions based on the detected first magnetic field value.

[0048] For example, in evaluation unit 14, one or more transition ranges B1, B2 are defined for the second magnetic field value, wherein each transition range B1, B2 contains a corresponding second magnetic field value at which a transition from one loop to the next occurs. For example, the first transition range B1 contains the second magnetic field value that generates the transition from the first loop U0 to the second loop U1, and the second transition range B2 contains the second magnetic field value that generates the transition from the second loop U1 to the third loop U2.

[0049] Each transition range B1, B2 contains a corresponding consecutive numerical interval. Transition ranges B1, B2 are spaced apart from each other. For example, each transition range B1, B2 contains the values ​​that the noisy second magnetic field value might take during the corresponding transition from one loop to the next.

[0050] In response to the second magnetic field value being below the first transition range B1, the evaluation unit 14 infers the number of rotations to be 0. The evaluation unit 14 multiplies the number of rotations by 360 degrees and adds the rotation direction to the result in order to calculate a single, definite rotation position.

[0051] In response to the second magnetic field value being within the first transition range B1, evaluation unit 14 calculates the numbers "0" and "1" as candidate values ​​for the number of rotations. Evaluation unit 14 uses the rotation direction to determine which of the two candidate values ​​is correct. For example, evaluation unit 14 compares the rotation direction with a rotation direction threshold (specifically 180 degrees). In response to the rotation direction being greater than the rotation direction threshold, evaluation unit 14 selects the smaller of the two candidate values ​​as the number of rotations, which is "0" in this example. In response to the rotation direction being less than the rotation direction threshold, evaluation unit 14 selects the larger of the two candidate values ​​as the number of rotations, which is "1" in this example. Evaluation unit 14 multiplies the selected number of rotations by 360 degrees and adds the rotation direction to the result to calculate a single, defined rotation position.

[0052] Evaluation unit 14 handles other possible cases in a similar manner. If the second magnetic field value is between the transition ranges B1 and B2, evaluation unit 14 infers the number of rotations to be "1". If the second magnetic field value is within the second transition range B2, evaluation unit 14 determines whether the number of rotations is "1" or "2" based on the direction of rotation. If the second magnetic field value is above the second transition range B2, evaluation unit 14 infers the number of rotations to be "2". In each case, evaluation unit 14 multiplies the determined number of rotations by 360 degrees and adds the direction of rotation to the result to calculate a single, definite rotational position.

[0053] refer to Figure 3 The following will discuss a design in which the second magnetic element 7 can move past the magnetic field sensor device 2. In this case, in particular, the sign of the third magnetic field component or the second magnetic field value may change.

[0054] exist Figure 3 In the view, the rotational position-angle range is plotted on the horizontal axis, which here includes two cycles U0 and U1. On the vertical axis, a first curve 15 for the first magnetic field value and a second curve 16 for the second magnetic field value are plotted.

[0055] During the drive motion 3, the second magnetic element 7 moves through the magnetic field sensor device 2 within the transition segment A of the rotational position-angle range. Within the transition segment A, there is a transition 18 from one revolution U0 of the rotating motion component 4 to the next revolution U1. The evaluation unit 14 is configured to determine the number of revolutions within the transition segment A, taking into account the first magnetic field value.

[0056] For example, a transition range B for the second magnetic field value is defined in evaluation unit 14. The transition range B includes the second magnetic field value at the transition 18 from loop U0 to the next loop U1. In particular, the transition range B includes the possible values ​​of the second magnetic field value that may take at the transition 18 from loop U0 to the next loop U1, even if there is noise.

[0057] In response to the detected second magnetic field value being outside the transition range B and being negative, the evaluation unit 14 infers that the number of rotations is 0. The evaluation unit 14 then determines this rotation direction as a single, definite rotation position.

[0058] In response to the detected second magnetic field value being within the transition range B, evaluation unit 14 calculates the numbers "0" and "1" as candidate values ​​for the number of rotations. Evaluation unit 14 uses the rotation direction to determine which of the two candidate values ​​is correct. For example, evaluation unit 14 compares the rotation direction with a rotation direction threshold (specifically 180 degrees). In response to the rotation direction being greater than the rotation direction threshold, evaluation unit 14 selects the smaller of the two candidate values ​​as the number of rotations, which is "0" in this example. In response to the rotation direction being less than the rotation direction threshold, evaluation unit 14 selects the larger of the two candidate values ​​as the number of rotations, which is "1" in this example. Evaluation unit 14 multiplies the selected number of rotations by 360 degrees and adds the rotation direction to the result to calculate a single, definitive rotation position.

[0059] In response to the detected second magnetic field value being outside the transition range B and being positive, evaluation unit 14 infers the number of rotations as "1". Evaluation unit 14 adds the rotation direction to 360 degrees to calculate a single, definite rotation position.

[0060] Optionally, the evaluation unit 14 is configured to linearize and / or temperature compensate for the first magnetic field value and / or the second magnetic field value.

[0061] The following will refer to Figure 4 This section introduces an alternative solution, particularly useful when the rotational position-angle range exceeds two revolutions.

[0062] exist Figure 4 In the view, the rotational position-angle range is plotted on the horizontal axis, which here includes three cycles U0, U1, and U2. On the vertical axis, a first curve 15 for the first magnetic field value and a second curve 16 for the second magnetic field value are plotted.

[0063] Preferably, the evaluation unit 14 has a look-up table containing multiple value pairs (consisting of corresponding first magnetic field values ​​and second magnetic field values) and multiple rotational position values, wherein each value pair is assigned a corresponding rotational position value. Each rotational position value corresponds to a single, specific rotational position. The evaluation unit 14 is configured to determine this single, specific rotational position using the look-up table.

[0064] The value pairs (first magnetic field value and second magnetic field value) stored in the lookup table can also be referred to as "stored value pairs", "stored first magnetic field value", and "stored second magnetic field value". The value pairs (composed of first magnetic field value and second magnetic field value) detected by the magnetic sensor mechanism 2, the first magnetic field value and the second magnetic field value can also be referred to as "detected value pairs", "detected first magnetic field value", and "detected second magnetic field value".

[0065] Lookup tables can be created, for example, by calculation or simulation, or by iteratively approximating a reference point and performing corresponding measurements.

[0066] Preferably, within the range of the jump position of the curve that generates the first magnetic field value, i.e. especially at the transition from one circle to the next, the lookup table has a finer gradation than in other areas (especially relative to the rotation position value).

[0067] The lookup table is stored, for example, in the memory of the evaluation unit 14.

[0068] Appropriately, the second magnetic field value is temperature compensated.

[0069] Suitablely, if the detected value pair consisting of the first magnetic field value and the second magnetic field value is located between two pairs of values ​​stored in a lookup table, the evaluation unit 14 performs interpolation (e.g., linear interpolation or spline interpolation).

[0070] Preferably, the evaluation unit 14 uses the least squares method to search the lookup table for suitable value pairs to determine a single, definite rotation position.

[0071] As described above, the first magnetic field value is, for example, the rotation direction of the rotating motion element 4, and the second magnetic field value is, for example, the detected z-direction magnetic field component.

[0072] For example, for a detected first magnetic field value and a detected second magnetic field value, the evaluation unit 14 selects a stored value pair such that the deviation between the detected first magnetic field value and the stored first magnetic field value, and the deviation between the detected second magnetic field value and the stored second magnetic field value, are minimized. Based on this selected stored value pair and directly adjacent value pairs, the evaluation unit 14 then interpolates the rotational position values ​​assigned to these value pairs to calculate a single, definite rotational position.

[0073] The following describes a situation where, at the transition from one revolution to the next, where the curve of the rotation direction jumps from 360 degrees to 0 degrees, an intermediate value is erroneously detected as the first magnetic field value (i.e., the rotation direction), particularly a value less than 360 degrees (preferably less than 350 degrees) and greater than 0 degrees (preferably greater than 10 degrees). This situation is called the intermediate value case. When an analog sensor element is used as the magnetic field sensor device 2, the detected signal (representing the rotation direction) can only rise or fall at a finite rate, and this intermediate value is particularly prone to occur.

[0074] In the case of an intermediate value, where an intermediate value is (erroneously) detected for the first magnetic field value at the loop-transition point, the evaluation unit 14 is designed to identify that the value pair consisting of the detected first magnetic field value and the detected second magnetic field value does not match any stored value pair. To this end, the evaluation unit 14 is designed, for example, to check whether the deviation between the detected value pair and the stored value pairs (particularly all stored value pairs or selected stored value pairs) exceeds a predetermined limit. For example, for each stored value pair whose first magnetic field value is equal to the detected first magnetic field value (or within the error range of the detected first magnetic field value), the evaluation unit 14 checks whether the deviation between the detected second magnetic field value and the stored second magnetic field value exceeds a predetermined limit. If the deviation exceeds the limit, the evaluation unit 14 infers the existence of an intermediate value.

[0075] In response to the identification of an intermediate value, evaluation unit 14 identifies the loop-transition that best matches the detected second magnetic field value, for example, using a lookup table. Specifically, evaluation unit 14 identifies loop-transitions whose associated (stored) second magnetic field value is closest to the detected second magnetic field value. In particular, entries in the lookup table suitable as loop-transitions have a rotation position value of 360 degrees or an integer multiple of 360 degrees.

[0076] Evaluation unit 14 is configured to provide the identified rotational position value of the loop-transition as a single, definite rotational position.

[0077] Optionally, the evaluation unit 14 is configured to correct the detected rotation direction to 0 degrees in response to an intermediate value less than 180 degrees, and to select the larger of the two circle values ​​associated with the identified circle-transition in order to determine a single, definite rotation position. Furthermore, the evaluation unit 14 is configured to correct the detected rotation direction to 360 degrees in response to an intermediate value greater than 180 degrees, and to select the smaller of the two circle values ​​associated with the identified circle-transition in order to determine a single, definite rotation position. The evaluation unit 14 then multiplies the selected circle number by 360 degrees and adds the corrected rotation direction to the result.

Claims

1. An actuator device (1) for industrial automation, particularly a pneumatic pivot actuator or pneumatic gripper, comprising a magnetic field sensor device (2) and a drive device for performing a drive motion (3), wherein, The drive device has a rotary motion component (4) that includes a first magnetic element (5) and changes its rotational position relative to the magnetic field sensor device (2) within a rotational position-angle range of more than one revolution during the drive motion (3). The drive device also includes a linear motion component (6) that is kinematically coupled to the rotary motion component (4), the linear motion component having a second magnetic element (7) and moving linearly relative to the magnetic field sensor device (2) during the drive motion. The magnetic field sensor device (2) is configured to detect the magnetic fields of the first magnetic element (5) and the second magnetic element (7). The actuator device (1) also has an evaluation unit (14) configured to determine a single, definite rotational position of the rotary motion component (4) with respect to the rotational position-angle range based on the detected magnetic field.

2. The actuator device (1) according to claim 1, wherein, The evaluation unit (14) is configured to provide a first magnetic field value and a second magnetic field value using the magnetic field sensor device (2), wherein the first magnetic field value depends on the rotation direction of the first magnetic element (5), the second magnetic field value depends on the distance between the second magnetic element (7) and the magnetic field sensor device (2), and to determine the single definite rotation position based on the first magnetic field value and the second magnetic field value.

3. The actuator device (1) according to claim 2, wherein, The evaluation unit (14) is configured to provide the rotation direction of the rotating motion component (4) based on a detected first magnetic field value, and to determine the number of revolutions of the rotating motion component (4) based on a detected second magnetic field value, wherein the number of revolutions indicates which revolution (U0, U1, U2) the rotating motion component (4) is located in within the rotation position-angle range, and the evaluation unit (14) is configured to determine the single definite rotation position based on the rotation direction and the number of revolutions.

4. The actuator device (1) according to claim 3, wherein, The evaluation unit (14) is configured to determine the number of revolutions while taking into account the first magnetic field value.

5. The actuator device (1) according to claim 4, wherein, The evaluation unit (14) is configured to determine two successive candidate values ​​for the number of revolutions based on the detected second magnetic field value, and to select one of the two candidate values ​​for the number of revolutions as the number of revolutions based on the detected first magnetic field value.

6. The actuator device (1) according to any one of claims 3 to 5, wherein, During the driving motion (3), the second magnetic element (7) is able to move through the magnetic field sensor device within the transition segment (A) of the rotational position-angle range, wherein within the transition segment (A), there is a transition (18) from one revolution (U0) to the next revolution (U1) of the rotating motion component (4), and the evaluation unit (14) is configured to determine the number of revolutions within the transition segment (A) while taking into account the first magnetic field value.

7. The actuator device (1) according to any one of claims 2 to 6, wherein, The evaluation unit has a lookup table containing multiple value pairs and multiple rotation position values, the multiple value pairs consisting of a corresponding first magnetic field value and a corresponding second magnetic field value, wherein a corresponding rotation position value is assigned to each value pair, wherein the evaluation unit (14) is configured to determine the single definite rotation position by using the lookup table.

8. The actuator device (1) according to any one of the preceding claims, wherein, The first magnetic field value is based on a first magnetic field component and a second magnetic field component, and the second magnetic field value is based on a third magnetic field component, wherein the first magnetic field component, the second magnetic field component, and the third magnetic field component are orthogonally oriented to each other.

9. The actuator device (1) according to claim 8, wherein, The first magnetic field component and the second magnetic field component are orthogonally oriented to the rotation axis of the rotating motion component (4), and / or the third magnetic field component is oriented along the axial direction of the rotation axis of the rotating motion component (4).

10. The actuator device (1) according to any one of the preceding claims, wherein, The magnetic field sensor device is configured as a magnetic field sensor element, particularly a 3D Hall sensor.

11. The actuator device (1) according to any one of the preceding claims, wherein, The drive device is designed as a rack and pinion drive, the rotary motion component (4) includes a gear (17), and the linear motion component (6) includes a rack (8) that meshes with the gear (17).

12. A method for operating an actuator device according to any one of the preceding claims, comprising the steps of: - Execute driving motion; - Detect the magnetic fields of the first magnetic element and the second magnetic element using a magnetic field sensor device; as well as -Based on the detected magnetic field, the evaluation unit determines the single, specific rotational position.

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