JP2013042602A - Electric actuator and electric actuator system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric actuator which ensures the reliability of apparatus driving and achieves the simplification and the downsizing of the structure, which suppresses the increase of the weight and the costs and prevents partial failure from causing limitations on the overall operation.SOLUTION: A first electric motor 11 generates rotation driving torque transmitted to a first screw 23 and displaces a first output part 19 relative to a housing 13. A first nut runner 24 is integrally provided with the first output part 19, and the first screw 23 is installed so as to be locked by a first lock mechanism 16. A second screw 26 is fixed to a second output part 20 and a second nut runner 27 is installed so as to be locked by a second lock mechanism 17. The first screw 23 and the second screw 26 are installed on the same axis line. An end part of the second screw 26 is inserted into the inner side of a cylinder portion of the first screw 23 having a gap therebetween.

Description

  The present invention relates to an electric actuator that drives a device by being displaced so as to expand and contract along a linear direction, and an electric actuator system including the electric actuator.

  In aircraft, helicopters, flying objects, etc., actuators that drive various devices by being displaced so as to expand and contract along the linear direction are used. In such an actuator, a failure such as seizure or sticking may occur in a drive mechanism such as a gear or a screw. In addition, a failure may occur in the drive source, resulting in loss or deterioration of the function.

  In case of the occurrence of the above-mentioned failure, the actuator as described above is provided with a backup drive mechanism and a redundant structure to ensure reliability of device drive. Is important. Alternatively, in the actuator as described above, when a device is driven by another actuator different from the actuator in which the failure has occurred, a structure is provided that can operate following the operation without disturbing the operation of the other actuator. It is important to ensure the reliability of device drive.

  Patent Document 1 discloses an actuator in which a movable rod can be operated by using either an electric drive mechanism or a hydraulic drive mechanism, and redundancy is achieved. This actuator includes a cylinder, a piston, a movable rod connected to the piston, a screw shaft partially inserted into the movable rod, a nut that is screwed into the screw shaft and moves together with the piston, and an electric motor that rotationally drives the screw shaft , And is configured.

JP2007-1555075A

  Since the actuator disclosed in Patent Document 1 is configured as a hybrid actuator having an electric motor and a hydraulic cylinder mechanism, redundancy is achieved. However, the hybrid structure of the electric motor and the hydraulic cylinder mechanism complicates the structure, and further increases the weight and cost.

  It is considered possible to realize an electric actuator having a structure in which redundancy is achieved by using only an electric drive mechanism using an electric motor without using a hydraulic cylinder mechanism without using the above-described hybrid. As the electric actuator with such redundancy, two electric drive mechanisms including an electric motor and a drive mechanism such as a gear or a screw that transmits a driving force from the electric motor to drive the device are provided. The resulting structure is conceivable. And as an electric actuator provided with two electric drive mechanisms in this way, a structure in which two electric drive mechanisms are installed in parallel or in series can be considered.

  In the case of an electric actuator in which two electric drive mechanisms are installed in parallel, the electric drive mechanisms installed in parallel are respectively connected to devices to be driven. When a failure such as sticking occurs in one of the electric drive mechanisms, the influence of the failure occurs to the other electric drive mechanism in which no failure has occurred via the connected device to be driven. . That is, the malfunction of the failed electric drive mechanism is a factor that restricts the operation of the electric drive apparatus in which no failure has occurred through the device in which both the electric drive mechanisms are connected. In this way, a part of the faults restricts the entire operation. Furthermore, since the electric drive mechanism is installed in parallel, the electric actuator that drives the device by displacing along the linear direction increases the dimension in the width direction perpendicular to the displacement direction, and the structure is enlarged and installed. This will increase the space.

  Further, in the case of an electric actuator in which two electric drive mechanisms are installed in series, the longitudinal dimension, which is the displacement direction, increases, the structure becomes larger, and the installation space increases. Further, when a failure such as sticking occurs in one electric drive mechanism, in order to operate the other electric drive mechanism in which no failure has occurred, it is extremely long in order to ensure the movable range of the other electric drive mechanism. A stroke is required, which further increases the installation space. That is, as the movable range of the other electric drive mechanism, it is possible to position the other electric drive mechanism to the neutral position based on the position where the one electric drive mechanism is fixed, etc., and to ensure an operation stroke from the neutral position. Stroke is required. This also leads to complicating position control by the other electric drive mechanism in the event of a failure in one electric drive mechanism, and also the size of the position sensor for detecting the position. It will be long.

  In view of the above circumstances, the present invention can ensure the reliability of driving the device, simplify the structure and reduce the size, suppress the increase in weight and cost, and some failures restrict the overall operation. It is an object of the present invention to provide an electric actuator and an electric actuator system including the electric actuator.

  In order to achieve the above object, an electric actuator according to a first aspect of the present invention includes: a housing; a first output portion provided on one end side of the housing so as to project relative to the housing; A second output portion that protrudes relative to the housing on the side, is provided so as to be relatively displaceable, a first screw that is at least partially housed in the housing, and is attached to be relatively rotatable with respect to the first screw. In addition, a first nutrunner that is relatively displaceable in the axial direction with respect to the first screw by relative rotation, a second screw at least partially housed in the housing, and relative rotation with respect to the second screw A second nut that can be attached and can be relatively displaced in the axial direction with respect to the second screw by relative rotation A first electric motor that generates a rotational driving torque transmitted to any one of the runner, the first screw, and the first nutrunner, and displaces the first output portion with respect to the housing; A first lock mechanism that can be locked so as to restrict a relative rotational movement of the first nut runner relative to the first screw; and a second lock mechanism that can be locked so as to restrict a relative rotational action of the second nut runner relative to the second screw. One of the first screw and the first nutrunner is integrally provided or fixed to the first output portion, the other is installed so as to be lockable by the first lock mechanism, and the second One of the screw and the second nutrunner is integrally provided or fixed to the second output portion, and the other is the first nutrunner. The first screw and the second screw are installed along a coaxial line so that one of the first screw and the second screw is formed in a cylindrical shape. The other end of the first screw and the second screw is inserted inside the cylindrical portion with a gap interposed therebetween.

  According to this configuration, the first electric motor with the first locking mechanism releasing the locking operation of the first screw and the first nutrunner and the second locking mechanism operating the locking operation of the second screw and the second nutrunner. Operates. A device in which at least one of the first and second output units is connected by the relative rotation operation of the first screw and the first nutrunner caused by the rotational driving torque by the first electric motor to displace the first output unit. Is driven. Moreover, according to said structure, the other edge part is inserted in the state through the clearance gap inside one side of the 1st screw and the 2nd screw, and the mechanical connection of the 1st screw and the 2nd screw is cut off. It is. For this reason, even if a failure such as the fixation of the first screw and the first nut runner or the failure of the first electric motor occurs, the operation of the second screw and the second nut runner is not affected. Therefore, according to this structure, it can prevent that a part of failure will produce restrictions on the whole operation | movement.

  In addition, since the other end portion is inserted inside one of the first screw and the second screw installed along the coaxial line in the housing, the longitudinal direction which is the displacement direction and the width perpendicular thereto The structure can be downsized in any direction, and the installation space can be downsized. Furthermore, with the above configuration, the structure can be simplified, and an increase in weight and cost can be suppressed. Further, with the above configuration, the operation stroke of the second screw or the second nut runner when a failure such as sticking of the first screw and the first nut runner occurs is easy even with an electric actuator having a short longitudinal dimension. Secured.

  Further, according to the above configuration, even if a failure such as fixing of the drive mechanism such as the first screw and the first nut runner or a failure of the first electric motor occurs, the operation of the second screw and the second nut runner is performed. This ensures the displacement of the second output section. Therefore, by transmitting the rotational drive torque to either the second screw or the second nutrunner, a backup drive mechanism in the event of the above failure can be realized, and redundancy can be achieved. Alternatively, since the operation of the second screw and the second nutrunner is ensured, when the device is driven by another actuator different from the actuator in which the failure has occurred when the above failure occurs, It is possible to realize a structure that can follow and operate without hindering the operation. Therefore, according to said structure, the reliability of apparatus drive is securable.

  Therefore, according to the above configuration, the reliability of device driving can be secured, the structure can be simplified and miniaturized, the increase in weight and cost can be suppressed, and some failures cause restrictions on the overall operation. Therefore, it is possible to provide an electric actuator that can prevent the above-described phenomenon.

  An electric actuator according to a second invention is the electric actuator according to the first invention, wherein the electric actuator according to the first invention generates a rotational driving torque transmitted to any one of the second screw and the second nutrunner, and It is further provided with the 2nd electric motor which displaces the 2nd output part.

  According to this configuration, the second electric motor is released in a state where the second locking mechanism releases the locking operation of the second screw and the second nut runner and the first locking mechanism operates the locking operation of the first screw and the first nut runner. Operates. A device in which at least one of the first and second output units is connected by the relative rotation of the second screw and the second nutrunner caused by the rotational driving torque generated by the second electric motor to displace the second output unit. Is driven. For this reason, in this configuration, even if a failure such as fixation of the drive mechanism such as the first screw and the first nutrunner or a failure of the first electric motor occurs, the second screw as a backup drive mechanism and The second nutrunner can be operated by the second electric motor, and redundancy is achieved.

  The electric actuator according to a third aspect is the electric actuator according to the first aspect or the second aspect, wherein the first lock mechanism restricts the rotation of the rotation shaft of the first electric motor, thereby The first nutrunner is locked so as to restrict the relative rotational operation thereof.

  According to this configuration, the first lock mechanism is provided so as to restrict the rotation of the rotation shaft of the first electric motor, and is configured efficiently and compactly so as to be integrated with the first electric motor. For this reason, the electric actuator can be further miniaturized.

  The electric actuator according to a fourth aspect of the present invention is the electric actuator according to any one of the first to third aspects of the invention, wherein the second lock mechanism is in a state in which the relative rotation operation of the second nutrunner with respect to the second screw is restricted. When the rotational torque generated to rotate the second nut runner relative to the second screw is transmitted from the second screw or the second nut runner and the rotational torque is greater than or equal to a predetermined magnitude, Slip is caused, and relative rotation of the second nutrunner with respect to the second screw is allowed.

  According to this configuration, when the rotational torque from the second screw or the second nut runner side is equal to or larger than a predetermined magnitude, the second lock mechanism slips and the relative rotation of the second screw and the second nut runner is allowed. Therefore, when a failure occurs in the first screw, the first nutrunner, the first electric motor, etc., that is, when a failure occurs in the driving force transmission path from the first electric motor to the first output unit, the failure occurs. When the device is driven by another actuator that is different from the electric actuator that generates the error, a structure that allows the operation of the second screw and the second nutrunner when a rotational torque greater than a predetermined magnitude is applied is easily realized. it can. Therefore, it is possible to realize a mechanism capable of following up without disturbing the operation of other actuators and capable of a damping operation (attenuating operation) with a simple structure.

  The electric actuator according to a fifth aspect of the present invention is the electric actuator according to any one of the first to fourth aspects of the present invention, comprising a case and a probe that is displaced relative to the case, and a position for detecting a relative position of the probe with respect to the case A detection mechanism is further provided, and one of the case and the probe is disposed so as to be displaceable together with the first output unit, and the other of the case and the probe is disposed so as to be displaceable together with the second output unit. It is characterized by.

  According to this configuration, the other position relative to one of the first and second output units is determined by a simple position detection mechanism in which one of the case and the probe is installed in the first output unit and the other is installed in the second output unit. Can be detected. Further, according to this configuration, one position detection is performed both when a failure occurs in the first screw, the first nutrunner, the first electric motor, and the like, and when no failure occurs. Position information for controlling the stroke of the electric actuator can be detected by the mechanism.

  As another aspect of the invention, an invention of an electric actuator system including the above-described electric actuator can also be configured. In other words, an electric actuator system according to a sixth aspect of the present invention includes the electric actuator according to the fifth aspect of the present invention and a controller that controls the operation of the electric actuator, and the electric actuator includes the second screw and the second nutrunner. A second electric motor that generates a rotational driving torque transmitted to any one of the first and second housings and displaces the second output portion with respect to the housing, and the controller detects the detection result of the position detection mechanism. Based on this, it is possible to output a rotation command to the second electric motor so that the position of the second output unit with respect to the first output unit is a predetermined neutral position.

  According to this configuration, when a failure occurs in the first screw, the first nutrunner, the first electric motor, or the like, the controller drives the second electric motor based on the detection result of the position detection mechanism, and the first Control can be performed so that the position of the second output unit with respect to the output unit is a predetermined neutral position. Accordingly, the electric actuator can be quickly controlled by positioning the second screw or the second nutrunner to the neutral position in accordance with the position of the first screw or the first nutrunner that is malfunctioning due to failure. .

  According to the present invention, the reliability of device driving can be ensured, the structure can be simplified and miniaturized, the increase in weight and cost can be suppressed, and a part of the failure can restrict the overall operation. An electric actuator that can be prevented can be provided.

It is a mimetic diagram showing the state where the electric actuator concerning one embodiment of the present invention was attached to the wing and control surface of an airplane. It is a front view of the electric actuator shown in FIG. It is sectional drawing of the electric actuator shown in FIG. It is a figure showing typically an electric actuator system concerning one embodiment of the present invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following embodiments, an example in which an electric actuator is provided in an aircraft moving blade drive mechanism for driving aircraft moving blades will be described. However, the present invention is not limited to the embodiments exemplified in the following embodiments, and can be widely applied to electric actuators that drive devices by being displaced so as to expand and contract along a linear direction. For example, the present invention can be applied to an electric actuator used in an aircraft, a helicopter, or a flying object. As for aircraft and helicopters, the present invention can be applied to electric actuators used in either manned aircraft or unmanned aircraft.

  FIG. 1 is a schematic diagram showing a state in which an electric actuator 1 according to an embodiment of the present invention is attached to an aircraft wing 101 and a control surface 102. In describing the electric actuator 1, first, the moving blade driving mechanism 100, which is an example to which the electric actuator 1 is applied, will be described. A moving blade drive mechanism 100 including the electric actuator 1 shown in FIG. 1 is installed in an aircraft in which only the wing 101 and the control surface 102 are shown in FIG. The moving blade driving mechanism 100 is used to drive the control surface 102 of the aircraft.

  As the moving blade (control blade surface) of the aircraft constituting the control surface 102, an auxiliary wing (aileron), a rudder (ladder), an elevator (elevator), and the like can be given. Further, the moving blade driving mechanism 100 including the electric actuator 1 may be used as a mechanism for driving a moving blade configured as a flap, a spoiler, or the like.

  FIG. 2 is a front view of the moving blade driving mechanism 100 including the electric actuator 1. In FIG. 2, a part of the control surface 102 is shown in a cutout state. As shown in FIGS. 1 and 2, the moving blade driving mechanism 100 is configured as a link driving mechanism including an electric actuator 1 and a reaction link 103 connected to the electric actuator 1.

  The electric actuator 1 is provided as an actuator that drives the control surface 102 that is a device of the present embodiment by being displaced so as to expand and contract along the linear direction. An end portion on one end side of the electric actuator 1 is rotatably attached to a swing shaft 104 attached to the control surface 102 via a bearing or a bush as a cylindrical sliding member. Thereby, the electric actuator 1 is attached to one end side of the control surface 102 so as to be swingable.

  The reaction link 103 is provided as a member that supports the reaction force from the control surface 102 by the output when the output from the electric actuator 1 is output to the control surface 102. In the reaction link 103, the load received by the movable control surface 102 that swings with respect to the wing 101 does not directly affect the fixed wing 101 on which the control surface 102 is swingably supported. It is provided to ensure that

  One end of the reaction link 103 is attached to a fulcrum shaft 105 that rotatably supports the control surface 102 with respect to the wing 101 side. Note that an end portion on one end side of the reaction link 103 is rotatably attached to the fulcrum shaft 105 via a bearing or a bush as a cylindrical sliding member, for example. Accordingly, the reaction link 103 is attached to one end side thereof so as to be swingable with respect to the fulcrum shaft 105. Further, the fulcrum shaft 105 and the swing shaft 104 are provided so that the axial directions thereof extend in parallel to each other. The distance between the fulcrum shaft 105 and the oscillating shaft 104 ensures the length of the torque arm necessary for driving the control surface 102 by oscillating around the fulcrum shaft 105 by the operation of the electric actuator 1. It is set appropriately so that it can be done.

  In addition, the reaction link 103 is formed, for example, so as to be bifurcated from one end side attached to the fulcrum shaft 105 to the other end side on the opposite side. A part of the electric actuator 1 is disposed between the bifurcated portions of the reaction link 103. In addition, each end portion of the reaction link 103 on the other end side branched into two branches is swingably attached to the other end side opposite to the one end side attached to the swing shaft 104 in the electric actuator 1. . Each end of the reaction link 103 on the other end side is connected to a connecting shaft 106 that rotatably connects the electric actuator 1 and the reaction link 103 with each other via a bearing or a bush as a cylindrical sliding member. It can be rotated freely. The electric actuator 1 and the reaction link 103 are rotatably supported with respect to the wing 101 via a connecting shaft 106.

  Next, the electric actuator 1 according to this embodiment will be described in detail. FIG. 3 is a cross-sectional view of the electric actuator 1. The electric actuator 1 shown in FIGS. 1 to 3 includes a first electric motor 11, a second electric motor 12, a housing 13, a first drive mechanism 14, a second drive mechanism 15, a first electromagnetic clutch 16, and a second electromagnetic clutch 17. The position detection mechanism 18 is provided. In FIG. 3, the first electric motor 11, the second electric motor 12, the first electromagnetic clutch 16, and the second electromagnetic clutch 17 are not illustrated in cross section but are shown in outline.

  The housing 13 houses main parts of the first drive mechanism 14 and the second drive mechanism 15, and the first electric motor 11 and the second electric motor 12 are fixed to the housing 13. In addition, the 1st output part 19 in the 1st drive mechanism 14 mentioned later is provided in the state which exposed from the edge part of the one end side with respect to the housing 13, and protruded. Further, the second output unit 20 in the second drive mechanism 15 to be described later is provided in a state of protruding from the end on the other end side of the housing 13.

  The first electric motor 11 is configured as an electric motor capable of forward / reverse rotation operation and performing feedback control based on a command from an actuator controller 21 described later. The first electric motor 11 is provided as an electric motor that generates rotational driving torque transmitted to the first drive mechanism 14 and displaces the first output unit 19 with respect to the housing 13.

  The second electric motor 12 is configured as an electric motor capable of forward / reverse rotation and performing feedback control based on a command from an actuator controller 21 described later. The second electric motor 12 is provided as an electric motor that generates a rotational driving torque transmitted to the second drive mechanism 15 and displaces the second output unit 20 with respect to the housing 13.

  The first drive mechanism 14 includes a first output unit 19, a first gear unit 22, a first screw 23, a first nut runner 24, and the like.

  The first output portion 19 is provided as an end portion on one end side of the electric actuator 1 and is rotatably attached to the swing shaft 104. The first output portion 19 projects from the housing 13 on one end side of the housing 13 so as to be relatively displaceable, and outputs a driving force generated by the rotational driving torque transmitted from the first electric motor 11. It is configured.

  The first screw 23 is housed in the housing 13 and is rotatably supported inside the housing 13. The first screw 23 includes a screw shaft portion 23a and a gear portion 23b that are integrally formed. The screw shaft portion 23a is formed as a hollow and cylindrical portion, and a spiral screw groove is provided on the outer periphery. The end on one end side of the screw shaft portion 23a is inserted into a hole 19a provided in a cylindrical portion of the first output portion 19 and opened in the housing 13 through a gap. Has been placed.

  Moreover, the hollow gear part 23b is integrally provided in the edge part of the other end side of the screw shaft part 23a. An external gear is formed on the outer periphery of the gear portion 23b. The hollow area | region of the screw shaft part 23a and the gear part 23b is continuing, and is comprised as a through-hole which penetrates the 1st screw 23 in this embodiment.

  The first nut runner 24 is attached so as to be rotatable relative to the outer periphery of the screw shaft portion 23 a of the first screw 23. Moreover, in this embodiment, the 1st nut runner 24 is provided as a cylindrical part, for example, and the helical thread groove is provided in the inner periphery. The first nut runner 24 is provided integrally with the first output unit 19 on the other end side opposite to the one end side connected to the swing shaft 104 in the first output unit 19. The hollow region of the first nut runner 24 and the hole 19a of the first output portion 19 are continuous, and are arranged in a state where the screw shaft portion 23a of the first screw 23 is inserted.

  A plurality of balls 30 circulate and roll between the inner peripheral thread groove of the first nut runner 24 and the outer peripheral thread groove of the screw shaft portion 23a of the first screw 23. . That is, the first screw 23 and the first nut runner 24 constitute a ball screw mechanism. When the first screw 23 rotates about the shaft center, the ball 30 rolls between the screw groove of the screw shaft portion 23 a and the screw groove of the first nut runner 24, and the first nut runner 24 moves inside the housing 13. Thus, the first screw 23 is displaced in the axial direction.

  As described above, the first nut runner 24 is rotated relative to the screw shaft portion 23a, so that the first nut runner 24 is relative to the first screw 23 in the axial direction, that is, relative to the screw shaft 23a in the axial direction. It is configured to be displaceable. In the present embodiment, the first screw 23 is rotated and the first nut runner 24 is displaced in the axial direction with respect to the first screw 23. However, the opposite configuration is implemented. Also good. That is, the form which a 1st nut runner rotates and a 1st screw displaces to the axial direction of a 1st screw with respect to a 1st nut runner may be implemented.

  The first nut runner 24 is installed in the housing 13 such that the outer periphery thereof is slidable with respect to the inner wall 13 a of the housing 13. When the first nut runner 24 is displaced in the axial direction of the first screw 23 in the housing 13 as the first screw 23 rotates, the first output portion 19 provided integrally with the first nut runner 24 also moves to the housing 13. It will be displaced.

  The displacement of the first nut runner 24 in the axial direction of the first screw 23 in the first housing 13 is a stroke restricting portion (13b, 13b, provided as a step portion capable of contacting the first nut runner 24 in the housing 13). 13c). That is, the stroke of the first nut runner 24 is regulated so that it can be displaced in the axial direction of the first screw 23 in the region between the stroke regulating part 13b and the stroke regulating part 13c.

  Further, between the first output portion 19 and the housing 13, in which the first nut runner 24 is integrally provided, the displacement in the rotational direction around the axial centers of the first nut runner 24 and the first output portion 19 is restricted. A detent mechanism 28 is provided. The anti-rotation mechanism 28 is provided as a link mechanism in which a plurality of link members are connected, and one end portion is attached to the first output portion 19 and the other end portion is attached to the housing 13.

  The first gear unit 22 includes a spar gear 22a provided as a large diameter gear and a pinion gear 22b provided as a small diameter gear. The spur gear 22a is fixed to the rotating shaft 11a of the first electric motor 11, and the rotational driving torque of the first electric motor 11 is input thereto. The pinion gear 22 b is rotatably supported in the housing 13 and is installed so as to mesh with both the spar gear 22 a and the gear portion 23 b of the first screw 23. The pinion gear 22b receives the rotational drive torque input to the spar gear 22a, accelerates this rotation, and transmits it to the gear portion 23b of the first screw 23. As described above, the rotational drive torque generated by the first electric motor 11 is transmitted to the first screw 23 via the first gear unit 22. The first gear unit 22 and the gear portion 23b may be configured as a gear mechanism other than the spur gear mechanism. For example, the first gear unit 22 and the gear part 23b may be configured as a helical gear mechanism.

  The second drive mechanism 15 includes a second output unit 20, a second gear unit 25, a second screw 26, a second nut runner 27, and the like.

  The second output portion 20 is provided as an end portion on the other end side of the electric actuator 1 and is rotatably attached to the connecting shaft 106. The second output unit 20 projects from the housing 13 on the other end side of the housing 13 so as to be relatively displaceable, and outputs a driving force generated by the rotational driving torque transmitted from the second electric motor 12. It is configured as follows.

  The second screw 26 is configured as a screw shaft member partially housed in the housing 13. The second screw 26 is formed as a round bar-like member having a through hole formed in the center, and a screw is provided on the outer periphery.

  Further, the end of one end of the second screw 26 is inserted into a hollow region formed in the gear portion 23b and the screw shaft portion 23a of the first screw 23, and a gap is formed with respect to the inside of the first screw 23. It is arrange | positioned in the state inserted through. That is, in the present embodiment, the first screw 23, which is one of the first screw 23 and the second screw 26, has a cylindrical part, and the first screw 23 has a first part inside the cylindrical part. The end of the second screw 26, which is the other of the screw 23 and the second screw 26, is inserted with a gap interposed therebetween. On the other hand, the other end of the second screw 26 protrudes from the other end of the housing 13 and is fixed to the second output unit 20.

  Moreover, the 1st screw 23 and the 2nd screw 26 are installed along the coaxial line. That is, the axis of the first screw 23 and the axis of the second screw 26 are arranged on the same line.

  The second nut runner 27 is rotatably supported inside the housing 13 and is attached to the outer periphery of the second screw 26 so as to be relatively rotatable. Further, in the present embodiment, the second nut runner 27 includes, for example, a cylindrical portion 27a provided as a cylindrical portion, and a flange-shaped end portion on one end side of the cylindrical portion 27a. And a formed gear portion 27b.

  A second screw 26 is inserted through a central through hole formed in the cylindrical portion 27 a of the second nut runner 27. For this reason, the axis of the second nut runner 27 is set to coincide with the axis of the second screw 26. A screw is formed on the inner periphery of the cylindrical portion 27 a, and the inner peripheral screw of the cylindrical portion 27 a is screwed to the outer peripheral screw of the second screw 26. As a result, the second nut runner 27 rotates about the shaft center, so that the second screw 26 screwed into the second nut runner 27 moves in the axial direction of the second screw 26 and the second nut runner 27 with respect to the housing 13. Will be displaced.

  As described above, the second nut runner 27 is configured to be relatively displaceable in the axial direction with respect to the second screw 26 by rotating relative to the second screw 26. In the present embodiment, the second nut runner 27 rotates and the second screw 26 is displaced in the axial direction with respect to the second nut runner 27. However, the reverse configuration is implemented. Also good. That is, a form in which the second screw rotates and the second nut runner is displaced in the axial direction with respect to the second screw may be implemented.

  Further, when the second screw 26 is displaced in the axial direction along with the rotation of the second nut runner 27, the second output portion 20 fixed to the second screw 26 is also displaced with respect to the housing 13. In addition, the displacement of the rotation direction centering on the axial center of the 2nd screw 26 and the 2nd output part 20 is regulated between the 2nd output part 20 and the housing 13 in which the 2nd screw 26 was provided integrally. A detent mechanism 29 is provided. The anti-rotation mechanism 29 is provided as a link mechanism in which a plurality of link members are connected, and one end is attached to the housing 13 and the other end is attached to the second output unit 20.

  The second gear unit 25 includes a spur gear 25a provided as a large diameter gear and a pinion gear 25b provided as a small diameter gear. The spur gear 25a is fixed to the rotating shaft 12a of the second electric motor 12, and the rotational driving torque of the second electric motor 12 is input thereto. The pinion gear 25 b is rotatably supported in the housing 13 and is installed so as to mesh with both the spar gear 25 a and the gear portion 27 b of the second nut runner 27. The pinion gear 25b receives the rotational drive torque input to the spar gear 25a, accelerates this rotation, and transmits it to the gear portion 27b of the second nut runner 27. As described above, the rotational drive torque generated by the second electric motor 12 is transmitted to the second nut runner 26 via the second gear unit 25. The second gear unit 25 and the gear portion 27b may be configured as a gear mechanism other than the spur gear mechanism. For example, the second gear unit 25 and the gear portion 27b may be configured as a helical gear mechanism.

  The first electromagnetic clutch 16 is provided as a first locking mechanism of the present embodiment that can be locked so as to restrict the relative rotational operation of the first nut runner 24 with respect to the first screw 23. And in this embodiment, the 1st electromagnetic clutch 16 is attached with respect to the 1st electric motor 11, and regulates rotation of the rotating shaft 11a of the 1st electric motor 11, via the 1st gear unit 22. The first nut runner 24 relative to the first screw 23 is configured to be locked so as to restrict the relative rotational operation.

  In the present embodiment, the first nut runner 24, which is one of the first screw 23 and the first nut runner 24, is provided integrally with the first output unit 19. The first screw 23, which is the other of the first screw 23 and the first nut runner 24, is installed so as to be lockable by the first electromagnetic clutch 16 via the first gear unit 22.

  Moreover, the 1st electromagnetic clutch 16 is comprised as a meshing clutch or a friction clutch, for example. The first electromagnetic clutch 16 is configured, for example, to operate a locking operation by the clutch by a spring force in a non-excited state and release the locking operation by the clutch against the spring force in an excited state. .

  The second electromagnetic clutch 17 is provided as a second locking mechanism of the present embodiment that can be locked so as to restrict the relative rotational operation of the second nutrunner 27 with respect to the second screw 26. And in this embodiment, the 2nd electromagnetic clutch 17 is attached with respect to the 2nd electric motor 12, and controls the rotation of the rotating shaft 12a of the 2nd electric motor 12, and thereby via the 2nd gear unit 25. The second nut 26 is configured to lock so as to restrict the relative rotation of the second nut runner 27 with respect to the second screw 26.

  In the present embodiment, the second screw 26 and the second nut runner 27 are fixed to the second output unit 20 with the second screw 26 being one of them. The second nut runner 27, which is the other of the second screw 26 and the second nut runner 27, is installed so as to be lockable by the second electromagnetic clutch 17 via the second gear unit 25.

  Moreover, the 2nd electromagnetic clutch 17 is comprised as a meshing clutch or a friction clutch, for example. The second electromagnetic clutch 17 is configured, for example, to operate a locking operation by the clutch by a spring force in a non-excited state and release the locking operation by the clutch against the spring force in an excited state. .

  The position detection mechanism 18 includes a case 31 and a probe 32 that is displaced with respect to the case 31, and is provided as a mechanism that detects the relative position of the probe 32 with respect to the case 31. In the position detection mechanism 18, the main parts of the probe 32 and the case 31 are disposed inside the first output unit 19 and the first screw 23.

  The probe 32 includes a shaft member 32a, a mounting portion 32b fixed to the shaft member 32a, and a core 32c. The shaft-shaped member 32 a is installed so as to extend along the axial direction of the first screw 23 from the hole 19 a of the first output portion 19 to the hollow region inside the first screw 23. The shaft-like member 32a is made of, for example, SUS300 stainless steel.

  The attachment portion 32b is provided at an end portion on one end side of the shaft-like member 32a, and is fixed to the first output portion 19 by, for example, screwing so that the probe 32 is attached to the first output portion 19. It is configured. Accordingly, the probe 32 is supported in a cantilever manner with respect to the first output unit 19. In addition, with this configuration, in this embodiment, the probe 32 that is one of the case 31 and the probe 32 is installed so as to be displaceable together with the first output unit 19.

  The core 32 c of the probe 32 is provided at the end of the shaft-like member 32 a on the other end side, and is configured as a movable iron core that is displaced relative to the case 31 inside the case 31. The core 13 is formed of, for example, permalloy, which is an Fe—Ni alloy, or electromagnetic soft iron.

  The case 31 is provided as a cylindrical structure fixed to the end portion on the one end side of the second screw 26, and is disposed in a hollow region inside the first screw 23. The end of the probe 32 on the other end side is inserted inside the case 31, and the core 32 c is disposed inside the case 31 so as to be relatively displaceable with respect to the case 31. In addition, the case 31 is fixed to the end portion on the one end side of the second screw 26 at the end portion on the other end side, and is supported in a cantilever manner with respect to the second screw 26. Thereby, in this embodiment, case 31 which is the other of case 31 and probe 32 is installed displaceably with 2nd output part 20 to which the 2nd screw 26 was fixed.

  Although not shown in FIG. 3, the case 31 is provided with a position detection signal output unit that outputs a position detection signal of the core 32 a of the probe 32 with respect to the case 31 inside the case 31. The position detection signal output unit includes a coil that is held by the case 31 and in which the core 32c is disposed so as to be displaceable. The position detection signal output unit generates an induced voltage when the core 32c is displaced while the primary side coil is excited with the input voltage applied and the primary side coil is excited. And a signal based on the induced voltage generated in the secondary coil as a position detection signal. This position detection signal is transmitted to an actuator controller 21 described later via a cable 33 extending to the outside through a through hole inside the second screw 26.

  Next, an electric actuator system 10 including the electric actuator 1 will be described. FIG. 4 is a diagram schematically showing an electric actuator system 10 according to an embodiment of the present invention. As shown in FIG. 4, the electric actuator system 10 includes an electric actuator 1, drivers (34 a and 34 b), and an actuator controller 21.

  The driver 34 a is configured as a motor driving device that drives the first electric motor 11 based on a command signal from the actuator controller 21. On the other hand, the driver 34 b is configured as a motor driving device that drives the second electric motor 12 based on a command signal from the actuator controller 21.

  The actuator controller 21 is provided as a controller of the present embodiment that controls the operation of the electric actuator 1. The actuator controller 21 is configured to control the operation of the electric actuator 1 based on a command signal from a host computer (not shown) that commands the operation of the control surface 102. Then, the actuator controller 21 performs the first electric drive via the driver 34a based on the detection result of the position detection mechanism 18, that is, based on the position detection signal transmitted from the position detection signal output unit of the position detection mechanism 18. The operating state of the motor 11 is controlled, and the position of the first output unit 19 with respect to the case 13 is controlled.

  Furthermore, the actuator controller 21 controls the operation state of the second electric motor 12 via the driver 34b based on the detection result of the position detection mechanism 18, and can also control the position of the second output unit 20 with respect to the case 13. It is configured. The actuator controller 21 detects the position according to the position where the first output unit 19 is stopped with respect to the housing 13 when a failure occurs in the first electric motor 11 or the first drive mechanism 14. Based on the detection result of the mechanism 18, a rotation command for the second electric motor 12 can be output so that the position of the second output unit 20 with respect to the first output unit 19 becomes a predetermined neutral position.

  The actuator controller 21 is also configured to control the operating states of the first electromagnetic clutch 16 and the second electromagnetic clutch 17. That is, the first electromagnetic clutch 16 is switched between an excited state and a non-excited state based on a command signal from the actuator controller 21. Similarly, the second electromagnetic clutch 17 is switched between an excited state and a non-excited state based on a command signal from the actuator controller 21.

  Next, the operation of the electric actuator 1 and the electric actuator system 10 will be described. In a normal state where no failure has occurred in the electric actuator 1, the operation of the electric actuator 1 by the operation of the first electric motor 11 is performed based on a command from the actuator controller 21.

  In the above case, the first electromagnetic clutch 16 is energized by a command from the actuator controller 21, the lock operation by the spring force is released, and the rotation shaft 11a of the first electric motor 11 can be rotated. On the other hand, the second electromagnetic clutch 17 is not excited by a command from the actuator controller 21 and is in a non-excited state, operates a lock operation by a spring force, and restricts the rotation of the rotating shaft 12a of the second electric motor 12. Yes. Thereby, the second nut runner 27 is locked by the second electromagnetic clutch 17 via the second gear unit 25. And the relative displacement of the 2nd screw 26 with respect to the 2nd nut runner 27 does not arise, but the position with respect to the housing 13 of the 2nd output part 20 is hold | maintained without changing.

  In the above state, the rotation of the first electric motor 11 is controlled based on a command signal from the actuator controller 21. As the first electric motor 11 rotates, the spar gear 22a rotates together with the rotating shaft 11a, and the pinion gear 22b that meshes with the spar gear 22a also rotates. Further, the rotation of the pinion gear 22b is transmitted to the gear portion 23b of the first screw 23, and the first screw 23 rotates about the axis.

  When the first screw 23 rotates, a plurality of balls 30 between the screw shaft portion 23 a and the first nut runner 24 roll, and the first screw 23 rotates while the first nut runner 24 rotates relative to the first screw 23. Displacement in the axial direction. As a result, the first nut runner 24 is displaced in the axial direction of the first screw 23 with respect to the housing 13 together with the first output unit 19 whose rotation about the axis is restricted by the rotation stop mechanism 28.

  By the above operation, the first output portion 19 is displaced so as to expand or contract with respect to the housing 13. Then, the control surface 102 is driven by the driving force generated between the first output unit 19 and the second output unit 20 as the electric actuator 1 expands or contracts in this way. That is, the control surface 102 is driven by being urged by the electric actuator 1 that can swing around the connecting shaft 106. The reaction link 103 is attached to one end side with respect to the fulcrum shaft 105 and the other end side with respect to the connecting shaft 106, and the control surface 102 is centered on the fulcrum shaft 105 as the electric actuator 1 is operated. It will be driven by swinging as follows.

  When the first electric motor 11 rotates in a predetermined direction, the first output unit 19 is displaced so as to extend from the housing 13, and the first electric motor 11 rotates in a direction opposite to the predetermined direction. As a result, the first output portion 19 is displaced so as to contract with respect to the housing 13. The position of the first output unit 19 relative to the housing 13 is controlled by the actuator controller 21 based on the detection result of the position detection mechanism 18.

  On the other hand, a failure may occur in the driving force transmission path from the first electric motor 11 to the first output unit 19, that is, in the first electric motor 11 or the first drive mechanism 14. In this case, based on a command from the actuator controller 21, the operation of the first electric motor 11 is stopped and the operation of the electric actuator 1 by the operation of the second electric motor 12 is performed.

  The failure in the driving force transmission path from the first electric motor 11 to the first output unit 19 includes a failure of the first electric motor 11, a failure such as seizure or sticking in the first gear unit 22, a first screw 23 and a first screw. A failure such as seizure or sticking in the one nut runner 24 may occur. Such a failure is detected, for example, by detecting an overcurrent of the current supplied to the first electric motor 11 or detecting a temperature rise by a temperature sensor (not shown) installed in the electric actuator 1. .

  When a failure is detected in the driving force transmission path from the first electric motor 11 to the first output unit 19, the failure detection signal is transmitted to the actuator controller 21. When the actuator controller 21 receives the failure detection signal, the actuator controller 21 releases the excitation of the first electromagnetic clutch 16 to shift to the non-excitation state, and shifts to the state in which the locking operation by the spring force is activated. Thereby, the rotation of the rotating shaft 11 a of the first electric motor 11 is restricted, and the first screw 23 is locked by the first electromagnetic clutch 16 via the first gear unit 22. And the relative displacement of the 2nd nut runner 24 with respect to the 1st screw 23 does not arise, and the position with respect to the housing 13 of the 1st output part 19 is hold | maintained without changing irrespective of the condition of a failure.

  Further, when the actuator controller 21 receives the failure detection signal, the actuator controller 21 excites the second electromagnetic clutch 17 to release the lock operation by the spring force, so that the rotating shaft 12a of the second electric motor 12 can be rotated. Transition. Accordingly, the electric actuator 1 can be operated by the operation of the second electric motor 12.

  Further, the actuator controller 21 is based on the detection result of the position detection mechanism 18 in a state where the locking operation of the first electromagnetic clutch 16 is activated and the locking operation of the second electromagnetic clutch 17 is released as described above. A rotation command for the second electric motor 12 is output so that the position of the second output unit 20 with respect to the first output unit 19 is a predetermined neutral position.

  For example, the first output portion is output by a predetermined stroke from the neutral position of the first output portion 19 with respect to the housing 13 in a state before a failure occurs in the driving force transmission path from the first electric motor 11 to the first output portion 19. It is assumed that the above-mentioned failure occurs with the position of 19 shifted. In this case, based on the detection result of the position detection mechanism 18, the actuator controller 21 outputs the second output unit 20 by the predetermined stroke that is the amount of deviation from the neutral position of the first output unit 19 before the failure occurs. A rotation command for the second electric motor 12 is output so as to be displaced with respect to the housing 13.

  According to the above, when the failure occurs, the position of the second output unit 20 with respect to the first output unit 19 is adjusted to a predetermined neutral position according to the position where the first output unit 19 is stopped with respect to the housing 13. The centering operation will be performed. That is, the position of the second output unit 20 relative to the first output unit 19 is adjusted according to the amount of deviation from the neutral position of the first output unit 19 before the failure occurs. In the state where the first output unit 19 is located at the neutral position before the failure occurs and the state where the centering operation is performed after the failure occurs and the second output unit 20 is located at the new predetermined neutral position. The distance between the peristaltic shaft 104 connected to the first output unit 19 and the connecting shaft 106 connected to the second output unit 20 is the same.

  After the centering operation is completed, the rotation of the second electric motor 12 is controlled based on a command signal from the actuator controller 21. As the second electric motor 12 rotates, the spur gear 25a rotates together with the rotating shaft 12a, and the pinion gear 25b that meshes with the spur gear 25a also rotates. Further, the rotation of the pinion gear 25b is transmitted to the gear portion 27b of the second nut runner 27, and the second nut runner 27 rotates about the axis.

  When the second nut runner 27 rotates, the second screw 26 is displaced in the axial direction of the second screw 26 while rotating relative to the second nut runner 27. As a result, the second screw 26 is displaced in the axial direction of the second screw 26 with respect to the housing 13 together with the second output unit 20 whose rotation about the axis is restricted by the rotation stop mechanism 29.

  By the above operation, the second output unit 20 is displaced so as to expand or contract with respect to the housing 13. Then, the control surface 102 is driven by the driving force generated between the first output unit 19 and the second output unit 20 as the electric actuator 1 expands or contracts in this way. In other words, the control surface 102 is urged by the electric actuator 1 that can swing about the connecting shaft 106, and the control surface 102 is driven to swing about the fulcrum shaft 105. Further, the position of the second output unit 20 with respect to the housing 13 is controlled by the actuator controller 21 based on the detection result of the position detection mechanism 18.

  As described above, according to the present embodiment, the first electromagnetic clutch 16 releases the locking operation of the first screw 23 and the first nut runner 24, and the second electromagnetic clutch 17 is connected to the second screw 26 and the second nut runner 27. The first electric motor 11 operates in a state where the locking operation is activated. Then, the rotational driving torque by the first electric motor 11 causes the relative rotation of the first screw 23 and the first nut runner 24 to displace the first output unit 19, and the control surface 102 to which the first output unit 19 is connected. Is driven. Further, according to the present embodiment, the end of the second screw 26 is inserted inside the first screw 23 with a gap interposed therebetween, and the mechanical connection between the first screw 23 and the second screw 26 is disconnected. Yes. For this reason, even if a failure such as fixing of the first screw 23, the first nut runner 24, and the first gear unit 22 or a failure of the first electric motor 11 occurs, the second screw 26 and the second nut runner 27 It will not affect the operation. Therefore, according to the present embodiment, it is possible to prevent some failures from restricting the entire operation.

  Moreover, according to this embodiment, since the other end is inserted inside one of the first screw 23 and the second screw 26 installed along the coaxial line in the housing 13, the displacement direction Thus, the structure can be downsized in both the longitudinal direction and the width direction perpendicular thereto, and the installation space can be made compact. Furthermore, with the above configuration, the structure can be simplified, and an increase in weight and cost can be suppressed. Also, with the above configuration, the operation stroke of the second screw 26 when a failure such as sticking of the first screw 23 and the first nut runner 24 occurs is easy even with the electric actuator 1 having a short longitudinal dimension. Secured.

  Further, according to the present embodiment, even if a failure such as the fixing of the drive mechanism such as the first screw 23 and the first nut runner 24 or the failure of the first electric motor 11 occurs, the second screw 26 and the second screw 26. The operation of the nut runner 27 is ensured, and the second output unit 20 can be displaced. Therefore, by transmitting the rotational drive torque to either the second screw 26 or the second nut runner 27, it is possible to realize a backup drive mechanism at the time of occurrence of the above-mentioned failure, and to achieve redundancy. Therefore, the reliability of the control surface driving is ensured. In the present embodiment, the electric actuator 1 used in the moving blade drive mechanism 100 that drives the control surface 102 has been described as an example. However, the present invention is not limited to this example, and other devices than the control surface 102 are driven. Alternatively, the electric actuator 1 may be used. Thereby, the reliability of device drive is ensured.

  Therefore, according to the present embodiment, it is possible to ensure the reliability of device driving, simplify the structure and reduce the size, suppress the increase in weight and cost, and some failures cause restrictions on the overall operation. It is possible to provide the electric actuator 1 that can prevent the electric actuator 1 and the electric actuator system 10 including the electric actuator 1.

  Further, according to the present embodiment, the second electromagnetic clutch 17 releases the locking operation of the second screw 26 and the second nut runner 27, and the first electromagnetic clutch 16 operates the locking operation of the first screw 23 and the first nut runner 24. In this state, the second electric motor 12 operates. Then, the rotational driving torque by the second electric motor 12 causes the relative rotation operation of the second screw 26 and the second nut runner 27 to displace the second output unit 20, and the control surface 102 to which the first output unit 19 is connected. Is driven. For this reason, in this configuration, even if a failure such as the fixing of the drive mechanism such as the first screw 23, the first nut runner 24, the first gear unit 22 or the like or the failure of the first electric motor 11 occurs, the backup The second screw 26 and the second nut runner 27 as the drive mechanism can be actuated by the second electric motor 12, and redundancy is achieved.

  Further, according to the present embodiment, the first electromagnetic clutch 16 is provided so as to restrict the rotation of the rotating shaft 11 a of the first electric motor 11, and is configured efficiently and compactly so as to be integrated with the first electric motor 11. Is done. For this reason, the electric actuator 1 can be further miniaturized.

  In addition, according to the present embodiment, the first output unit 19 and the probe 32 are configured by the simple position detection mechanism 18 configured such that one of the case 31 and the probe 32 is installed in the first output unit 19 and the other is installed in the second output unit 20. The other position of the second output unit 20 with respect to one can be detected. Moreover, according to this structure, when the failure of the 1st screw 23, the 1st nut runner 24, the 1st gear unit 22, the 1st electric motor 11, etc. has generate | occur | produced, and when the failure has not occurred In any case, the position information for controlling the stroke of the electric actuator 1 can be detected by one position detection mechanism 18.

  Further, according to the present embodiment, when a failure occurs in the first screw 23, the first nut runner 24, the first gear unit 22, the first electric motor 11, etc., the actuator controller 21 is operated by the position detection mechanism 18. Based on the detection result, the second electric motor 12 can be driven to control the position of the second output unit 20 with respect to the first output unit 19 to be a predetermined neutral position. As a result, the second screw 26 or the second nut runner 27 is positioned to the neutral position in accordance with the position of the first screw 23 or the first nut runner 24 that is malfunctioning due to failure, and the electric actuator 1 is quickly controlled. It can be performed.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. For example, the following modifications may be made.

(1) In the above-described embodiment, the electric actuator in the aircraft moving blade driving mechanism for driving the moving blade of the aircraft and the form configured as a system including the electric actuator have been described as an example. Good. INDUSTRIAL APPLICABILITY The present invention can be widely applied as an electric actuator that drives an apparatus by being displaced so as to expand and contract along a linear direction and a system including the same. For example, the present invention can be applied to an actuator that is used in an aircraft, a helicopter, or a flying body and that drives various devices by being displaced so as to expand and contract along a linear direction. In this case, regarding the aircraft and the helicopter, the present invention can be applied to both manned aircraft and unmanned aircraft.

(2) In the above embodiment, the first screw is rotatably supported with respect to the housing, and the first nut runner is displaced with respect to the first screw and the housing. However, this is not the case. Also good. The first nut runner may be mounted in such a manner that it can be relatively rotated with respect to the first screw and can be relatively displaced in the axial direction with respect to the first screw by relative rotation. For example, a form in which the first nut runner is rotatably supported with respect to the housing and the first screw is displaced with respect to the first nut runner and the housing may be implemented.

(3) In the above embodiment, the second nut runner is rotatably supported with respect to the housing and the second screw is displaced with respect to the second nut runner and the housing. However, this is not the case. Also good. The second nut runner may be mounted in such a manner as to be relatively rotatable with respect to the second screw and may be relatively displaced in the axial direction with respect to the second screw by being relatively rotated. For example, a form in which the second screw is rotatably supported with respect to the housing and the second nut runner is displaced with respect to the second screw and the housing may be implemented.

(4) In the above-described embodiment, the rotational driving torque of the first electric motor is transmitted to the first screw, and the first screw is installed so as to be locked by the first lock mechanism (electromagnetic clutch). Although the embodiment in which the nut runner is provided integrally with the first output unit has been described as an example, this need not be the case. That is, the rotational driving torque of the first electric motor is transmitted to either the first screw or the first nut runner, and one of the first screw and the first nut runner is provided integrally with the first output unit, or A mode in which the other side is fixed and can be locked by the first locking mechanism may be implemented.

(5) In the above-described embodiment, the rotational drive torque of the second electric motor is transmitted to the second nut runner, and the second nut runner is installed so as to be locked by the second lock mechanism (electromagnetic clutch). Although the example in which the screw is fixed to the second output unit has been described as an example, this need not be the case. That is, the rotational driving torque of the second electric motor is transmitted to either the second screw or the second nut runner, and one of the second screw and the second nut runner is provided integrally with the second output unit, or A mode in which the other side is fixed and can be locked by the second locking mechanism may be implemented.

(6) In the above-described embodiment, the first screw and the first nut runner constitute a ball screw mechanism, and the second screw and the second nut runner are screwed together. However, this need not be the case. That is, the first nut runner may be configured to be rotatable relative to the first screw and to be relatively displaced in the axial direction relative to the first screw by this relative rotation. And the 2nd nut runner should just be the structure which can be relatively displaceable to an axial direction with respect to a 2nd screw by the relative rotation with respect to a 2nd screw. As a form in which the first or second nut runner rotates relative to the first or second screw and relatively displaces in the axial direction, various forms other than a ball screw mechanism and screwing can be adopted. For example, a roller screw mechanism A form using may be adopted. In the case of the roller screw mechanism, a plurality of screw-shaped roller shafts each having a spiral groove on the outer periphery are rotatably installed between the first or second screw and the first or second nut runner. With the rotation of the first or second screw, or with the rotation of the first or second nut runner, each roller shaft is in relation to the first or second screw and the first or second nut runner. Engage with each other in a spiral groove and rotate around each axis.

(7) In the above-described embodiment, the first gear unit is provided between the first electric motor and the first screw or the first nut runner, and the first gear unit is provided between the second electric motor and the second screw or the second nut runner. The embodiment in which the two-gear unit is provided has been described as an example, but this need not be the case. The form in which the 1st gear unit and the 2nd gear unit are not provided may be sufficient.

  In the above case, the first electric motor, the first screw, the first nutrunner, and the first output unit may be installed along the coaxial line. For example, the first nut runner is fixed to the rotor of the first electric motor, and the first screw integrally provided or fixed to the first output unit is installed through the rotor and the first nut runner. It may be a configuration. In this case, the first screw is attached so as to be relatively rotatable with respect to the first nut runner fixed to the rotor of the first electric motor, and the first nut runner rotates together with the rotor, whereby the first screw is displaced in the axial direction. Will do. Even if the first screw is fixed to the rotor of the first electric motor and the first nut runner is integrally provided or fixed to the first output portion and attached to the first screw so as to be relatively rotatable. Good.

  Further, the second electric motor, the second screw, the second nutrunner, and the second output unit may be installed along the coaxial line. For example, the second nut runner is fixed to the rotor of the second electric motor, and the second screw integrally provided or fixed to the second output unit is installed through the rotor and the second nut runner. It may be a configuration. In this case, the second screw is attached so as to be relatively rotatable with respect to the second nut runner fixed to the rotor of the second electric motor, and the second nut runner rotates together with the rotor, whereby the second screw is displaced in the axial direction. Will do. Note that the second screw is fixed to the rotor of the second electric motor, and the second nut runner is integrally provided or fixed to the second output portion and attached to be relatively rotatable with respect to the second screw. Good.

(8) In the above-described embodiment, an example in which the operation of the electric actuator by the operation of the second electric motor is performed when the first electric motor or the first drive mechanism fails is described as an example. . An embodiment in which the operation of the electric actuator by the operation of the second electric motor is not performed may be performed. For example, when the second electromagnetic clutch is provided as a friction clutch and a rotational torque of a predetermined magnitude or larger is applied to the second electric motor from the second gear unit, the second electromagnetic clutch that operates the lock operation slips. And a configuration that allows relative rotation of the second nutrunner with respect to the second screw may be implemented. In this case, the second electromagnetic clutch can function as a friction damper. When the operation of the second screw and the second nutrunner is ensured, when the device is driven by another actuator different from the electric actuator in which the failure has occurred, the other actuator It is possible to realize a structure that can be operated by following without disturbing the operation. Therefore, the reliability of device driving can be ensured also by the above configuration.

(9) In the above-described embodiment, the embodiment in which the second electric motor is provided has been described as an example. However, this may not be the case, and an embodiment in which the second electric motor is not provided may be implemented. In this case, for example, a second lock mechanism may be provided that restricts the rotation of the second nutrunner relative to the second screw by restricting the rotation of the rotation shaft of the spur gear of the second gear unit. In this case, the rotational torque generated so that the second lock mechanism rotates the second nut runner relative to the second screw in a state in which the relative rotation operation of the second nut runner relative to the second screw is restricted. When the torque is transmitted from the second nut runner and the rotational torque is greater than or equal to a predetermined magnitude, a form may be implemented in which slipping occurs and the second nut runner is allowed to rotate relative to the second screw.

  According to the above modification, when the rotational torque from the second screw or the second nut runner side is equal to or larger than a predetermined magnitude, the second lock mechanism slips and the relative rotation of the second screw and the second nut runner is allowed. The For this reason, when a failure occurs in the first screw, the first nutrunner, the first electric motor, etc., when the device is driven by another actuator different from the electric actuator in which the failure has occurred, a predetermined size or more is required. The structure which permits the operation of the second screw and the second nutrunner when the rotational torque is applied can be easily realized. Therefore, it is possible to realize a mechanism capable of following up without disturbing the operation of other actuators and capable of a damping operation (attenuating operation) with a simple structure.

  The present invention can be widely applied to an electric actuator that drives an apparatus by being displaced so as to expand and contract along a linear direction and an electric actuator system including the electric actuator.

DESCRIPTION OF SYMBOLS 1 Electric actuator 11 1st electric motor 13 Housing 16 1st lock mechanism 17 2nd lock mechanism 19 1st output part 20 2nd output part 23 1st screw 24 1st nut runner 26 2nd screw 27 2nd nut runner

Claims (6)

A housing;
A first output portion provided on one end side of the housing so as to protrude relative to the housing and be capable of relative displacement;
A second output portion provided on the other end side of the housing so as to protrude relative to the housing and be capable of relative displacement;
A first screw at least partially housed in the housing;
A first nut runner which is attached so as to be relatively rotatable with respect to the first screw and is relatively displaceable in the axial direction with respect to the first screw by rotating relatively;
A second screw at least partially housed in the housing;
A second nutrunner that is mounted so as to be relatively rotatable with respect to the second screw, and is relatively displaceable in the axial direction with respect to the second screw by rotating relatively;
A first electric motor that generates a rotational drive torque transmitted to any one of the first screw and the first nutrunner, and displaces the first output portion with respect to the housing;
A first locking mechanism that can be locked so as to restrict relative rotational movement of the first nutrunner with respect to the first screw;
A second lock mechanism that can be locked so as to restrict relative rotational movement of the second nutrunner with respect to the second screw;
With
One of the first screw and the first nutrunner is integrally provided or fixed to the first output unit, and the other is installed so as to be locked by the first lock mechanism.
One of the second screw and the second nutrunner is integrally provided or fixed to the second output portion, and the other is installed so as to be locked by the second lock mechanism,
The first screw and the second screw are installed along a coaxial line,
One of the first screw and the second screw has a part formed in a cylindrical shape, and the other end is inside the one cylindrical part of the first screw and the second screw with a gap between them. An electric actuator characterized by being inserted in a state where The electric actuator according to claim 1,
And a second electric motor that generates a rotational driving torque transmitted to one of the second screw and the second nutrunner, and displaces the second output portion with respect to the housing. An electric actuator characterized by that. The electric actuator according to claim 1 or 2,
The electric actuator characterized in that the first lock mechanism locks the first nut runner relative to the first screw by restricting the rotation of the rotary shaft of the first electric motor. . The electric actuator according to any one of claims 1 to 3,
In the second lock mechanism, rotational torque generated to rotate the second nut runner relative to the second screw in a state where the relative rotation operation of the second nut runner relative to the second screw is restricted. Alternatively, when the torque is transmitted from the second nut runner and the rotational torque is greater than or equal to a predetermined magnitude, slippage occurs and the relative rotation of the second nut runner with respect to the second screw is allowed. Electric actuator. The electric actuator according to any one of claims 1 to 4,
A case and a probe that is displaced with respect to the case, further comprising a position detection mechanism that detects a relative position of the probe with respect to the case;
One of the case and the probe is installed to be displaceable together with the first output unit,
The other of the case and the probe is installed so as to be displaceable together with the second output part. An electric actuator according to claim 5, and a controller for controlling the operation of the electric actuator,
The electric actuator includes: a second electric motor that generates a rotational driving torque transmitted to one of the second screw and the second nutrunner, and displaces the second output portion with respect to the housing. Have
The controller can output a rotation command for the second electric motor based on the detection result of the position detection mechanism so that the position of the second output unit with respect to the first output unit is a predetermined neutral position. An electric actuator system, characterized in that

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