Actuator with motor

Abstract

The invention relates to an actuator (1) of automation technology, which is provided for actuating a control element, such as a valve, said actuator comprising a force measuring device (70), which is provided for measuring a mechanical propulsion force that causes a movement of an output element when a spring-mounted device is deflected from a rest position, wherein the electronic operating circuit is designed to determine the drive efficiency of the actuator as a function of a force measurement of the movement of the output and a measurement of the mechanical motor force derived from the motor current and / or the motor voltage.

Description

Technical Field

[0001] The present invention relates to an actuator with an electric motor for operating a control element in automation technology. Such an actuator is also used in automation technology to operate a control element, such as a valve. For example, DE 10 2019 134 805 A1 discloses an actuator that uses motor current to determine motor temperature. Background Art

[0002] In actuators with electric motors, the actuator's drive system is subject to heavy loads over time, so wear and tear can reduce the actuator's efficiency. Summary of the Invention

[0003] The object of the present invention is to provide an actuator capable of measuring the efficiency of the actuator.

[0004] This object is achieved by an actuator according to independent claim 1 .

[0005] The actuator designed for operating a control element such as a valve according to the automation technology of the present invention comprises:

[0006] a housing having a housing wall;

[0007] electric motor;

[0008] electronic operating circuits for operating electric motors;

[0009] an output member having an output spindle or an output shaft, the output member being configured to operate a control member through axial or rotational movement of the output spindle or the output shaft;

[0010] a transmission configured to transmit a force or torque to an output member, wherein the transmission comprises a plurality of meshing components, such as gears or worms, which are mounted via a meshing component support, such as a transmission spindle or a transmission shaft;

[0011] The motor, transmission and electronic operating circuit are arranged in the housing.

[0012] wherein the electric motor is designed to drive the output member linearly or rotationally via a transmission device,

[0013] wherein the actuator has a device which is spring-mounted in the housing via a spring device, the spring-mounted device being formed by the output element, the engagement element, or the engagement element support,

[0014] in

[0015] The actuator has a force measuring device configured to measure a mechanical propulsion force that causes the output member to move when the spring-mounted device is deflected from a rest position.

[0016] Wherein, the electronic operating circuit is configured as follows:

[0017] The drive efficiency of the actuator is determined from a force measurement of the output element movement and a measurement of the mechanical motor force resulting from the motor current and / or the motor voltage.

[0018] By comparing the propulsion force required to move the output member (independent of the actuator's efficiency) with the motor force applied or generated by the motor, the actuator's drive efficiency can be determined. Actuator wear can be determined by measuring drive efficiency, particularly by observing changes in drive efficiency over time. If wear or long-term changes in efficiency are detected, electronic operating circuits can be configured to, for example, issue a warning message. For example, if system maintenance can be scheduled without significant inconvenience, system operators can replace the affected actuator. This can prevent costly emergency shutdowns or system failures.

[0019] In one embodiment, the force measuring device is designed to convert the deflection of the spring-mounted device from the rest position relative to the spring device into a measurement signal of an electronic measured variable that is dependent on the deflection, such as an inductance, a capacitance, a current or a voltage.

[0020] Therein, the force measuring device or the electronic operating circuit is designed to derive or calculate a measured value of the propulsion force from the measurement signal.

[0021] In one embodiment, the force measuring device has a sensor for generating a measurement signal, for example using a coil, a capacitor or a capacitor plate or a photodiode,

[0022] Therein, the force measuring device has a tapping arm which is designed to be moved by an axial or rotational movement of a spring-mounted device, thereby causing a change in the measurement signal of the electronic measured variable.

[0023] In one embodiment, the force measuring device comprises a lever device having a lever bearing and a first end and an opposite second end relative to the lever bearing,

[0024] wherein the measuring arm forms the first end and the second end is configured to influence the measured value of the electronic measured variable in a position-dependent manner,

[0025] Therein, the lever length at the first end is particularly smaller than the lever length at the second end.

[0026] By using a smaller lever length at the first end, small deflections of the spring-mounted device can be converted into larger changes in the measurement signal.

[0027] In one embodiment, the sensor has an end face, wherein the second end is designed to at least partially cover the end face, wherein the coverage ratio depends on the urging force acting on the spring device,

[0028] wherein the sensor comprises a coil, wherein the second end is permanently magnetic and / or electrically conductive, wherein the second end is configured to influence the inductance of the coil and the second end,

[0029] or wherein the sensor comprises a capacitor plate, wherein the second end is conductive, wherein the second end is configured to affect the capacitance of the capacitor plate and the second end,

[0030] Or wherein the sensor comprises a photodiode, wherein the second end is configured to attenuate or block incident light, such as attenuate or block incident light from an LED.

[0031] In one embodiment, the second end is disc-shaped.

[0032] In one embodiment, the measured value of the measurement signal occupies a value range having a maximum value and a minimum value, wherein in the power-free state of the output element the measured value of the measurement signal takes a value that is less than 30% of the difference between the maximum value and the minimum value and the average value of the value range, in particular less than 25% thereof, and preferably less than 20% thereof.

[0033] In this way, deflections of the spring-mounted device in both directions can be detected with a sufficient detection margin.

[0034] In one embodiment, the spring device has at least one first spring element and at least one second spring element.

[0035] wherein the at least one first spring element is configured to apply a force to resist deflection of the output member from the rest position in a first direction,

[0036] The at least one second spring element is configured to apply a force to resist a deflection of the output member from the rest position in a second direction opposite to the first direction.

[0037] In one embodiment, the spring-mounted device is formed by the output member,

[0038] Therein, the distance between the cross section of the first spring element and the cross section of the second spring element is less than 30%, in particular less than 25%, preferably less than 20%, of the diameter of the first spring element or the second spring element.

[0039] In this way, the spring mounting of the spring-mounted device can be designed to be compact.

[0040] In one embodiment, the output spindle is designed as a threaded spindle.

[0041] wherein the threaded spindle is rotationally fixed,

[0042] The output member has a spindle nut.

[0043] The motor is configured to drive the spindle nut to rotate via a transmission device, thereby causing the threaded spindle to move axially.

[0044] The output member is elastically mounted in the housing along the axial direction of the threaded spindle via a spring device.

[0045] In one embodiment, the spindle nut is radially supported by a rolling bearing which is at least partially arranged in a cylindrical recess of the housing wall.

[0046] The cylindrical recessed portion provides a stopper for the rolling bearing to prevent the rolling bearing from moving in a direction away from the housing along the cylindrical recessed portion.

[0047] wherein the rolling bearing contacts the stop element and / or is preloaded against the stop element in the rest position in the output element,

[0048] Therein, the at least one first spring element and the at least one second spring element act on the rolling bearing on a side of the rolling bearing facing the housing.

[0049] This contributes to the compact design of the actuator.

[0050] In one embodiment, the actuator has a spring plate fastened in the housing, the spring plate having a central opening through which the spindle nut is guided.

[0051] The spindle nut has a radial structure, in particular a flange, on the side of the spring plate facing away from the housing, which is designed to directly or indirectly serve as a stop for the spring plate.

[0052] Therein, the spring plate is designed as one of the at least one first spring elements.

[0053] This contributes to the compact design of the actuator.

[0054] In one embodiment, the spring plate is arranged outside the cylindrical recess, wherein the radial structure acts on the spring plate via a rolling bearing.

[0055] In one embodiment, the transmission has a first toothed component element, such as a gear wheel, which is rotationally fixedly connected to the spindle nut.

[0056] wherein the spring device comprises at least one spiral spring which engages the spindle nut and is designed as at least one of the at least one second spring elements,

[0057] Therein, the at least one spiral spring is arranged and clamped between the first engagement member element and the rolling bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The present invention is described below using exemplary embodiments.

[0059] Figure 1 shows a cross section of an exemplary actuator according to the present invention;

[0060] Figure 2 Shown Figure 1 An enlarged view of a local detail of the actuator shown in FIG;

[0061] Figure 3 shows a cross section of an exemplary actuator according to the present invention;

[0062] Figure 4a )and Figure 4b ) summarizes the sensors of the actuator according to the present invention. DETAILED DESCRIPTION

[0063] Figure 1 A cross-section of an exemplary actuator 1 according to the present invention is shown. The actuator comprises a housing 10 with a housing wall 11. An electric motor 20, an electronic operating circuit 30 for operating the motor, a transmission 50, and an output element 40 are arranged in the actuator housing. The output element comprises an output spindle 41 or an output shaft 42, wherein the output element is configured to operate a control element via axial or rotational movement of the output spindle or shaft. The transmission 50 is configured to transmit the force or torque of the motor to the output element and comprises a toothed element 51, such as a gear 51.1 or a worm 51.2, mounted on a toothed element support 52, such as a transmission spindle 52.1 or a transmission shaft 52.2. The motor is designed to move the output element axially or rotationally. The actuator comprises a spring-mounted device 61, which is spring-mounted by a spring device 60. The spring-mounted device can be formed by the output element shown here, or by one of the toothed elements or one of the toothed element supports. According to the invention, the actuator has a force measuring device 70 for measuring the mechanical force of the output member caused by the deflection of the spring-mounted device from the rest position, wherein the electronic operating circuit is used to determine the drive efficiency of the actuator based on the force measurement value associated with the output member movement and the measurement value of the mechanical motor force generated by the motor current and / or the motor voltage.

[0064] By comparing the propulsion force required to move the output member (independent of the actuator's efficiency) with the force applied or generated by the motor, the actuator's drive efficiency can be determined. Actuator wear can be determined by measuring drive efficiency, particularly by observing changes in drive efficiency over time. If wear or long-term changes in efficiency are detected, electronic operating circuits can be configured to, for example, issue a warning message. For example, if system maintenance can be scheduled without significant inconvenience, system operators can replace the affected actuator. This can prevent costly emergency shutdowns or system failures.

[0065] In one embodiment, the force measuring device 70 of the exemplary actuator according to the present invention is configured to convert a deflection of the spring-mounted device 61 from a rest position relative to the spring device 60 into a measurement signal of an electronic measurement variable that is correlated with the deflection, such as an inductance, a capacitance, a current or a voltage, wherein the force measuring device or the electronic operating circuit 30 is configured to derive or calculate a measured value of the force from the measurement signal.

[0066] Figure 2 Shown Figure 1 A detailed cross-section of an actuator 1 is shown. As shown here, the output element 40 of the actuator 1 can include a spindle-like output spindle 41 with a spindle nut 43, which is driven via a gear 51.1 via a transmission to move the output spindle axially. As shown here, the force measuring device can detect the axial movement of the output shaft, for example, via the spindle nut 43, via a lever arrangement 72 with a measuring arm 72.11.

[0067] The force measuring device shown here by way of example has a lever arrangement 72 having a lever bearing 72.01 and a first end 72.1 relative to the lever bearing and a second end 72.2, in particular opposite thereto, wherein the measuring arm forms the first end and the second end is configured to influence the measured value of the electronic measured variable in a position-dependent manner, wherein the lever length at the first end is in particular smaller than the lever length at the second end.

[0068] The sensor 70.1 of the force measuring device is configured to generate a measurement signal corresponding to the propulsion force. Here, the sensor element 71 of the sensor has an end face 71.1, wherein the second end 72.2 is designed to at least partially cover the end face, wherein the coverage ratio depends on the propulsion force of the counterspring device and affects the measurement signal.

[0069] The measured values ​​of the measurement signal occupy a value range having a maximum and a minimum value, wherein in one embodiment, in the force-free state of the output element, the measured values ​​of the measurement signal assume a value that is less than 30% of the difference between the maximum and minimum values ​​and the average value of the value range, in particular less than 25% thereof, and preferably less than 20% thereof. In this way, deflections of the spring-mounted device in both directions can be detected with a sufficient detection margin.

[0070] As shown here, the spring device 60 can have at least one first spring element 60.1 and at least one second spring element 60.2,

[0071] wherein the at least one first spring element is configured to apply a force to resist deflection of the output member 40 from the rest position in the first direction,

[0072] The at least one second spring element is configured to apply a force to resist a deflection of the output member from the rest position in a second direction opposite to the first direction.

[0073] As shown here, the spindle nut 43 can be radially supported by a rolling bearing 80, which is at least partially arranged in a cylindrical recess 11.1 of the housing wall, wherein the cylindrical recess provides a stop 11.11 for preventing the rolling bearing from moving in the direction of the side of the cylindrical recess facing away from the housing, wherein the rolling bearing contacts the stop and / or is prestressed against it when the output element 40 is in the idle position, wherein at least one first spring element 60.1 and at least one second spring element 60.2 act on the rolling bearing on its side facing the housing, wherein the rolling bearing 80 is arranged in the cylindrical recess 11.1 of the housing wall 11. The cylindrical recess provides a stop 11.11 for the rolling bearing. A spring plate 90 fastened to the housing has a central opening 91 through which the spindle nut 43 is guided. The spindle nut has a radial structure 43.1, in particular a flange, on the side of the spring plate facing away from the housing. This radial structure is designed to directly or indirectly serve as a stop for the spring plate, which is designed as one of the at least one first spring elements 60.1. The spring plate 90 is arranged outside the cylindrical recess 11.1, with the radial structure 43.1 acting on the spring plate via the rolling bearing 80. One of the toothing elements of the transmission 50 is rotationally fixedly connected to the spindle nut 43. The spring device 60 has at least one disc spring that engages the spindle nut and is designed as at least one of the at least one second spring elements 60.2. The at least one disc spring is arranged and clamped between the first toothing element and the rolling bearing. This allows the spring device 60 to be compact.

[0074] Figure 3A cross-section of an exemplary actuator 1 is shown, which can be equipped with a force measuring device according to the present invention. An electric motor 20 is designed to drive an output member 40 having a gear wheel 44 via a transmission 50 with a worm 51.2 as a meshing element 51. The worm is designed as a spring-mounted device 61, which is spring-mounted and clamped by a spring device 60 having a first spring element 60.1 and a second spring element 60.2 opposite the worm. The worm engages with the gear wheel 44 and deflects against the spring device in response to the propulsion force provided by the motor. According to the present invention, a force measuring device can also be provided in this actuator, which detects the deflection of the worm relative to the spring device.

[0075] exist Figure 4a )and Figure 4b ) schematically shows a sensor element 71. The sensor element may include a coil 71.2, such as Figure 4a ) as shown, wherein the second end is permanently magnetic and / or conductive, and wherein the second end is configured to affect the inductance of the coil and the second end.

[0076] The sensor element may include a capacitor plate 71.3, such as Figure 4b ), wherein the second end is conductive, wherein the second end is configured to affect the capacitance of the capacitor plate and the second end. Alternatively, the sensor element may include a photodiode 71.4, wherein the second end is configured to attenuate or block incident light, such as light generated by an LED.

[0077] The present invention is not limited to Figure 1 、 Figure 3 4 , the features of the embodiments may be interchanged if technically reasonable.

[0078] Reference Signs List

[0079] 1 Actuator

[0080] 10 Housing

[0081] 11 Shell wall

[0082] 11.1 Cylindrical concave depth

[0083] 11.11 Stoppers

[0084] 20 Electric Motor

[0085] 30 Electronic operating circuit

[0086] 40 output pieces

[0087] 41 Output spindle

[0088] 42 output shaft

[0089] 43 Spindle nut

[0090] 43.1 Radial Structure

[0091] 44 Gear

[0092] 50 Transmission

[0093] 51 Engaging parts

[0094] 51.1 Gear

[0095] 51.2 Worm

[0096] 52 Engaging component support

[0097] 52.1 Transmission spindle

[0098] 52.2 Transmission shaft

[0099] 60 Spring device

[0100] 60.1 First spring element

[0101] 60.2 Second spring element

[0102] 61 Spring mounted device

[0103] 70 Force measuring device

[0104] 70.1 Sensors

[0105] 71 sensor element

[0106] 71.1 End face

[0107] 71.2 Coil

[0108] 71.3 Capacitor Plates

[0109] 71.4 Photodiode

[0110] 72 Lever device

[0111] 72.01 Lever bearing

[0112] 72.1 First End

[0113] 72.11 Measuring arm

[0114] 72.2 Second End

[0115] 80 rolling bearings

[0116] 90 Spring Plate

[0117] 91 center opening

Claims

1. An actuator (1) for automation technology for operating a control element, such as a valve, comprising: a housing (10) having a housing wall (11); Electric motor (20); an electronic operating circuit (30) for operating the electric motor; an output member (40), the output member (40) having an output spindle (41) or an output rotating shaft (42), the output member being configured to operate the control member through axial movement or rotational movement of the output spindle or the output rotating shaft; A transmission (50) is provided for transmitting a force or torque of an electric motor to an output element, wherein the transmission comprises a plurality of meshing elements (51), such as gears (51.1) or worms (51.2), which are mounted via a meshing element support (52), such as a transmission spindle (52.1) or a transmission shaft (52.2); wherein the electric motor, the transmission device and the electronic operating circuit are arranged in the housing, wherein the electric motor is designed to drive the output member axially or rotationally via a transmission device, wherein the actuator comprises a spring-mounted device (61) in the housing via a spring device (60), the spring-mounted device being formed by the output element, one of the engagement elements or one of the engagement element supports, It is characterized in that The actuator has a force measuring device (70) arranged to measure a mechanical propulsion force causing movement of the output member when the spring-mounted device is deflected from a rest position. Wherein, the electronic operating circuit is configured as follows: The drive efficiency of the actuator is determined from a force measurement of the output element movement and a measurement of the mechanical motor force resulting from the motor current and / or the motor voltage.

2. The actuator according to claim 1, in, The force measuring device (70) is designed to convert a deflection of the spring-mounted device (61) relative to the spring device (60) from a rest position into a measurement signal of an electronic measured variable that is correlated with the deflection, such as an inductance, a capacitance, a current or a voltage, The force measuring device or the electronic operating circuit (30) is designed to derive or calculate a measured value of the propulsion force from the measurement signal.

3. The actuator according to claim 2, in, The force measuring device (70) comprises a sensor (70.1) for generating a measurement signal, for example using a coil, a capacitor or a photodiode, Therein, the force measuring device has a tapping arm (72.11) which is designed to be moved by an axial or rotational movement of the spring-mounted device, thereby causing a change in the measurement signal of the electronic measured variable.

4. The actuator according to claim 3, in, The force measuring device comprises a lever device (72) with a lever bearing (72.01) and a first end (72.1) and a second end (72.2) arranged in particular opposite relative to the lever bearing. wherein the measuring arm forms the first end and the second end is configured to influence the measured value of the electronic measured variable in a position-dependent manner, Therein, the lever length at the first end is particularly smaller than the lever length at the second end.

5. The actuator according to claim 4, in, The sensor (70.1) has a sensor element (71) with an end face (71.1), wherein the second end (72.2) is designed to at least partially cover the end face, wherein the covering ratio depends on the propulsion force acting on the spring device, wherein the sensor element comprises a coil (71.2), wherein the second end is permanently magnetic and / or electrically conductive, wherein the second end is configured to influence the inductance of the coil and the second end, or wherein the sensor element comprises a capacitor plate (71.3), wherein the second end is electrically conductive, wherein the second end is configured to influence a capacitance of the capacitor plate and the second end, Or wherein the sensor element comprises a photodiode (71.4), wherein the second end is configured to attenuate or block incident light, such as attenuate or block incident light from an LED.

6. The actuator according to claim 4 or 5, in, The second end (72.2) is disc-shaped.

7. The actuator according to any one of claims 2 to 6, in, the measured values ​​of the measurement signal occupy a value range having a maximum value and a minimum value, In this case, the measured value of the measurement signal in the power-free state of the output element takes a value smaller than 30% of the difference between the maximum and minimum values ​​and the average value of the value range, in particular smaller than 25% thereof, and preferably smaller than 20% thereof.

8. Actuator according to any one of the preceding claims, in, The spring device (60) comprises at least one first spring element (60.1) and at least one second spring element (60.2), wherein the at least one first spring element is configured to exert a force to resist a deflection of the output member (40) from a rest position in a first direction, wherein the at least one second spring element is arranged to apply a force to resist deflection of the spring-mounted device (61) from a rest position in a second direction opposite to the first direction.

9. The actuator according to claim 8, in, The at least one first spring element (60.1) and the at least one second spring element (60.2) surround the output member, wherein the distance between the cross section of the first spring element and the cross section of the second spring element is less than 30%, in particular less than 25%, preferably less than 20% of the diameter of the first spring element or the second spring element.

10. The actuator according to claim 9, in, The output spindle (41) is designed as a threaded spindle. wherein the threaded spindle is rotationally fixed, wherein the output member comprises a spindle nut (43), wherein the motor (20) is configured to drive the spindle nut to rotate via the transmission device, thereby causing the threaded spindle to move axially, The output member is elastically mounted in the housing along the axial direction of the threaded spindle via the spring device (60).

11. The actuator according to claim 10, in, The spindle nut (43) is radially supported by a rolling bearing (80), which is at least partially arranged in a cylindrical recess (11.1) of the housing wall. The cylindrical concave deep portion is provided with a stopper (11.11) for the rolling bearing to prevent the rolling bearing from moving in a direction away from one side of the housing along the cylindrical concave deep portion. wherein the rolling bearing contacts the stop element and / or is preloaded against the stop element in the rest position in the output element (40), The at least one first spring element (60.1) and the at least one second spring element (60.2) act on the rolling bearing on a side of the rolling bearing facing the housing.

12. The actuator according to claim 11, in, The actuator has a spring plate (90) fastened in the housing, the spring plate having a central opening (91) through which the spindle nut (43) is guided. wherein the spindle nut has a radial structure (43.1), in particular a flange, on the side of the spring plate facing away from the housing, which is designed to serve directly or indirectly as a stop for the spring plate, The spring plate is designed as one of at least one first spring element (60.1).

13. The actuator according to claim 11 or 12, in, The spring plate (90) is arranged outside the cylindrical recess (11.1), wherein the radial structure (43.1) acts on the spring plate via the rolling bearing (80).

14. The actuator according to claim 12 or 13, in, The first engaging member element of the transmission (50) is rotationally fixedly connected to the spindle nut (43), wherein the spring device (60) comprises at least one coil spring which engages the spindle nut and is designed as at least one of at least one second spring elements (60.2), Therein, the at least one coil spring is arranged and clamped between the first engagement member element and the rolling bearing.

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