JP2015061363A - Electric actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric actuator in which the output part can be advanced and retracted from the installation place of the electric actuator, even if secured state occurs, while simplifying and down-sizing the structure.SOLUTION: An electric actuator 1 is constituted to include two housings 3, 4 provided separately, a screw mechanism 10, and a relief mechanism 20. The relief mechanism 20 has regulation members 25, 26 for regulating relative movement of two housings 3, 4 when being inserted, respectively, across a first engaging part H,Hand a second engaging part H,Hformed in respective housings 3, 4, and a regulation member drive part 21 which allows relative movement of two housings 3, 4 by extracting the regulation members 25, 26 from at least one of the first engaging part H,Hand second engaging part H,H.

Description

  The present invention relates to an electric actuator that has a screw mechanism and converts a rotational driving force output by an electric motor into a linear driving force and outputs the linear driving force.

  Conventionally, electric actuators having an electric motor and a screw mechanism have been used in various fields such as aircraft. Such an electric actuator converts a rotational driving force output by the electric motor into a linear driving force by a screw mechanism and outputs the linear driving force. And this electric actuator drives various apparatus by displacing so that an output part may expand and contract along a linear direction with respect to a housing. The electric actuator has an advantage that the maintenance burden is less than that of a hydraulic actuator that operates when pressure oil is supplied.

  In the above-mentioned electric actuator, a fixed state (jammed state) may occur in the screw mechanism due to a cause such as twisting or seizing. When the electric actuator is stuck, it is difficult to move the output portion forward and backward with respect to the housing.

  Patent Document 1 discloses an electric actuator provided with a first actuator and a second actuator. The first actuator and the second actuator are installed so as to extend in opposite directions on the coaxial line. Each of the first actuator and the second actuator includes an electric motor and a ball screw mechanism. Thereby, even if this electric actuator is a case where the fixation state generate | occur | produces in the screw mechanism in one of the 1st and 2nd actuators, the other of the 1st and 2nd actuators can be operated. It is. For this reason, in this electric actuator, even when the above-described fixed state occurs, the output portion can be retracted to a position contracted with respect to the housing.

US Pat. No. 5,214,972

  However, the electric actuator disclosed in Patent Document 1 requires a double actuator provided to extend in the opposite direction on the same axis. Further, each of the double actuators requires an electric motor and a screw mechanism. For this reason, this electric actuator has a complicated structure and an increased size. In addition, the electric actuator increases in weight as the structure becomes larger.

  The present invention is for solving the above-described problem, and the object thereof is to separate the output portion from the installation position of the electric actuator and advance or retract it even if the electric actuator having the screw mechanism is fixed. It is possible to provide an electric actuator that can be simplified and downsized in structure.

  (1) In order to solve the above problems, an electric actuator according to an aspect of the present invention includes a cylindrical housing part formed in a cylindrical shape, and a base side provided as a separate member from the cylindrical housing part A housing having a housing part, a first screw at least partially housed in the cylindrical housing part, and a cylindrical part in which the first screw is installed inside, the first screw being On the other hand, the second screw is attached so as to be relatively rotatable about the axis of the first screw and is relatively displaceable in the axial direction of the first screw with respect to the first screw by relative rotation. And a screw mechanism having one of the first screw and the second screw, and rotates with respect to the cylindrical housing portion. A first electric motor for freely rotating an input-side screw, an output unit connected to or provided on an output-side screw provided as the other of the first screw and the second screw, and As a through hole formed in the other of the cylindrical housing part and the base side housing part, as a through hole or a first engaging part as a recess formed in one of the cylindrical housing part and the base side housing part A restricting member that restricts relative movement of the cylindrical housing part with respect to the base side housing part by being inserted across both of the second engaging parts, and the restricting member as the first engaging part And allowing the cylindrical housing portion to move relative to the base-side housing portion by removing from at least one of the second engaging portions. And a, a relief mechanism having a regulating member driving unit.

  In this configuration, during normal operation of the electric actuator, the restricting member is provided on both the first engaging portion and the second engaging portion formed in each of the two housing portions (the cylindrical housing portion and the base side housing portion). It is in a state of being inserted across. Thereby, since the relative movement of the cylindrical housing part with respect to the base part side housing part is controlled, it will be in the state where two housing parts were integrated. In this state, when the input side screw is driven to rotate by the first electric motor, the output side screw relatively rotates with respect to the input side screw, thereby being relatively displaced in the axial direction. As a result, the output unit is displaced so as to expand and contract along the linear direction with respect to the housing, and various devices connected to the output unit are moved with respect to the installation location of the electric actuator (location where the base side housing portion is attached). Can be driven.

  In this configuration, when a fixed state (jammed state) occurs in the screw mechanism and the input side screw and the output side screw become relatively unrotatable, the device connected to the output unit is in that state. Can be prevented from being fixed. Specifically, in this configuration, when a fixed state occurs, the restricting member driving unit is driven. If it does so, the control member inserted over both the 1st engaging part and the 2nd engaging part will be extracted from at least one engaging part. Then, relative movement of the cylindrical housing part with respect to the base side housing part is allowed. That is, the cylindrical housing part on the side connected to the device to be driven can be displaced in the axial direction relative to the base side housing part attached to the installation location of the electric actuator. Thereby, the 1st screw and the 2nd screw of the state integrated by the adhering state become displaceable to the axial center direction of a screw with respect to the installation location of an electric actuator.

  Therefore, in this configuration, even when the screw mechanism is stuck, the output portion can be moved forward and backward with respect to the base-side housing portion connected to the installation location of the electric actuator. it can. Furthermore, as described above, the structure for enabling the output portion to move forward and backward is realized by a relatively small and simple structure that includes a restricting member, a restricting member driving portion, and the like. For this reason, simplification and size reduction of the structure of the electric actuator are achieved.

  Therefore, according to this configuration, even if a fixed state occurs in the electric actuator having the screw mechanism, the output portion can be separated from the installation location of the electric actuator and moved forward and backward, and the structure can be simplified and An electric actuator that can be miniaturized can be provided.

  (2) Preferably, the first electric motor is formed in a substantially annular shape and is fixed to the cylindrical housing portion so as to be concentric with the cylindrical housing portion, and accommodated in the stator portion. And a substantially annular rotor portion that rotates relative to the stator portion, and the second screw as the input side screw is fixed inside the rotor portion.

  In this configuration, in the configuration in which the second screw is provided as the input side screw, it is possible to provide a configuration in which the output portion can be advanced and retracted with respect to the base side housing portion when the screw mechanism is fixed.

  (3) More preferably, the first screw serving as the output-side screw is a first screw that opens in the axial direction at a portion opposite to the output portion in the axial direction of the first screw. The first screw cylinder has a cylindrical portion, the base side housing portion is formed in a cylindrical shape, and a portion on one side in the axial direction is concentric with the axial center of the first screw cylindrical portion. And the electric actuator regulates rotation of the first screw with respect to the base side housing part between the first screw cylindrical part and the base side housing part, and with respect to the base side housing part. A slide support mechanism for allowing the first screw to slide;

  According to this configuration, the output part can be slid in the axial direction with respect to the base side housing part when the screw mechanism is fixed. Moreover, the slide support mechanism is formed inside the first screw cylindrical portion, more specifically, between the first screw cylindrical portion and the base side housing portion partially accommodated in the first screw cylindrical portion. Is done. Thereby, the enlargement of the electric actuator can be suppressed.

  (4) More preferably, the second electric motor provided as the restricting member driving portion is accommodated in the base side housing portion so that the output shaft of the second electric motor is along the axis of the base side housing portion. In this state, the first engagement portion is formed on the cylindrical housing portion, and the second engagement portion is formed on the base side housing portion, and is fixed to the base side housing portion. The member is formed in a rod shape that advances and retreats along the arrangement direction of the first engagement portion and the second engagement portion, and one end side is configured as a restriction pin accommodated in the base side housing portion, and the relief mechanism is A nut member formed with a female screw portion that is screwed into a male screw portion formed on the outer periphery of the output shaft of the second electric motor, and one end side of which is swingably connected to the nut member. The other side A link member that is swingably connected to the one end side of the pin, and the restriction pin is inserted across both the first engagement portion and the second engagement portion Thus, the restricting pin is removed from the first engaging portion by rotational driving of the output shaft.

  In this configuration, when the screw mechanism is in a fixed state, the restriction pin inserted across both the first engagement portion and the second engagement portion is in a state of being removed from the first engagement portion. The relief mechanism is activated.

  Specifically, in the relief mechanism, when the output shaft of the second electric motor is rotationally driven in a predetermined direction, the nut member screwed to the output shaft moves in a direction away from the regulation pin in the axial direction. . Then, the link member whose one end side is swingably connected to the nut member pulls the restriction pin swingably connected to the other side of the link member to the inside of the base side housing portion in the radial direction. Thereby, the regulation pin in a state of being inserted across both the first engagement portion and the second engagement portion can be in a state of being removed from the first engagement portion. Thereby, when the screw mechanism is fixed, the engagement of the cylindrical housing portion with the base side housing portion can be released, and the output portion can be advanced and retracted in the axial direction with respect to the base side housing portion.

  Moreover, in this structure, components, such as a nut member and a link member which comprise a part of relief mechanism, are accommodated in the inside of the base side housing part. Thereby, the enlargement of the electric actuator can be suppressed.

  (5) More preferably, the relief mechanism includes a pair of male screw portions that are formed on one side portion and the other side portion in the axial direction on the outer peripheral surface of the output shaft and have a reverse screw relationship with each other. A pair of nut members each having a female screw portion screwed to each male screw portion, and one end side of each of the nut members is swingably connected to each nut member, The other end side has a pair of the link members that are swingably connected to the one end side of the restriction pin.

  In this configuration, when the output shaft of the second electric motor rotates in a predetermined direction, the pair of nut members screwed to the output shaft are separated from the restriction pins in the axial direction, that is, separated from each other. Move in the direction you want. If it does so, a pair of link member with which each one end side was connected to the nut member so that rocking was possible, would pull the regulation pin connected in common with this pair of link members to the inside of the base side housing part in the diameter direction. That is, since the restriction pin can be advanced and retracted by the pair of link members, the restriction pin can be operated reliably.

  (6) More preferably, the cylindrical housing portion is formed with the two first engaging portions, and the base-side housing portion has two corresponding first engaging portions, respectively. In contrast, two second engaging portions are formed so as to overlap each other in the radial direction of the cylindrical housing portion, and the relief mechanism includes the corresponding first engaging portion and the first engaging portion, respectively. A pair of said link members which have a pair of said control pin inserted ranging over both 2 engaging parts, and are rockably connected with respect to the said one end side of each said control pin to the said relief mechanism There are two.

  In this configuration, the tubular housing portion and the base side housing portion can be engaged by the plurality of restriction pins, so that the two housing portions can be reliably engaged.

  According to the present invention, even when the electric actuator having the screw mechanism is fixed, the output portion can be separated from the installation location of the electric actuator and moved forward and backward, and the structure can be simplified and miniaturized. An electric actuator that can be realized can be provided.

It is a schematic diagram which shows the state by which the electric actuator which concerns on embodiment of this invention was attached with respect to the wing | blade and moving blade of an aircraft. FIG. 2 is a schematic diagram illustrating a state in which a moving blade is driven from the state illustrated in FIG. 1 by an electric actuator. It is sectional drawing which shows typically the structure of the electric actuator which concerns on embodiment of this invention, Comprising: It is a figure shown about the electric actuator at the time of normal operation | movement. It is a figure which expands and shows the relief mechanism vicinity in FIG. FIG. 5 is a cross-sectional view schematically showing the electric actuator when the screw mechanism is in a fixed state and the relief mechanism is operated, and is a view corresponding to FIG. 4. It is sectional drawing which shows typically the structure of the electric actuator which concerns on a modification, Comprising: It is a figure shown corresponding to FIG. It is sectional drawing which shows typically the structure of the electric actuator which concerns on a modification, Comprising: It is a figure shown corresponding to FIG. It is sectional drawing which shows typically the structure of the electric actuator which concerns on a modification, Comprising: It is a figure shown corresponding to FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following embodiment, an example in which an electric actuator is provided in a moving blade driving mechanism for driving a moving blade of an aircraft will be described. However, the present invention is not limited to the embodiments exemplified in the following embodiments, and can be widely applied. Specifically, the present invention can be widely applied to an electric actuator that has a screw mechanism and converts a rotational driving force output by an electric motor into a linear driving force and outputs the linear driving force.

  FIG. 1 is a schematic view illustrating a state where an electric actuator 1 according to an embodiment of the present invention is attached to a wing 101 and a moving blade 102 of an aircraft. In FIG. 1, the main part of the aircraft is not shown. In FIG. 1, a part of the blade 101, the moving blade 102, and the moving blade 103 are schematically illustrated. In the present embodiment, the wing 101 is configured as a main wing of an aircraft. The moving blade 102 is configured as a spoiler. In the present embodiment, the moving blade 102 is configured as a device driven by the electric actuator 1. The moving blade 103 is configured as a flap. FIG. 1 schematically shows a state in which the rear end portion of the wing 101 is viewed from the left-right direction of the aircraft. In FIG. 1, only the outlines of the blade 101 and the moving blades 102 and 103 are schematically illustrated.

[Rotating blade drive mechanism]
In describing the electric actuator 1, first, an aircraft moving blade drive mechanism 100, which is an example to which the electric actuator 1 is applied, will be described. A moving blade driving mechanism 100 shown in FIG. 1 is installed on a wing 101 of an aircraft. The moving blade driving mechanism 100 is used to drive the moving blade 102 of the aircraft. The moving blade drive mechanism 100 includes the electric actuator 1, a rotating shaft (not shown), and a swing shaft 105.

  The rotating shaft is installed on the wing 101. And the housing 2 of the electric actuator 1, specifically, the 2nd housing part mentioned later in detail is rotatably connected with the rotating shaft. Thereby, the electric actuator 1 is supported with respect to the wing | blade 101 so that rocking | fluctuation is possible centering | focusing on a rotating shaft.

  The swing shaft 105 is installed on the moving blade 102. And the end part of the output part 11b of the electric actuator 1 is connected with the moving blade 102 rotatably. The moving blade 102 is rotatably supported with respect to the fulcrum shaft 106. The fulcrum shaft 106 is installed on the wing 101. Thereby, the moving blade 102 is supported by the blade 101 so as to be swingable about the fulcrum shaft 106.

  In the electric actuator 1, the output portion 11 b is provided so as to protrude relative to the housing 2 and be relatively displaceable. That is, the output part 11 b is configured to be able to extend from the housing 2 by protruding from the housing 2. Further, the output portion 11b is configured to be capable of contracting with respect to the housing 2.

  FIG. 2 is a schematic diagram showing a state in which the moving blade 102 is driven from the state shown in FIG. 1 by the electric actuator 1 of the moving blade driving mechanism 100. FIG. 1 shows a state in which the output portion 11 b is retracted to a position where it is most contracted with respect to the housing 2. On the other hand, FIG. 2 shows a state in which the output portion 11 b is extended from the housing 2. As shown in FIGS. 1 and 2, the moving blade 102 is driven by the operation of the electric actuator 1. The moving blade 102 is driven to swing with respect to the blade 101 about the fulcrum shaft 106.

  Note that a reaction link may be further provided in the moving blade driving mechanism 100 shown in FIG. The reaction link is provided as a member that supports the reaction force from the moving blade 102 by the output when the output from the electric actuator 1 is output to the moving blade 102. The reaction link has one end connected to the rotation shaft and the other end connected to the fulcrum shaft 106. By providing the reaction link, it is possible to prevent the load received by the movable-side moving blade 102 from directly affecting the fixed-side blade 101.

[Constitution]
FIG. 3 schematically shows the electric actuator 1 and includes a partial cross section of the electric actuator 1. As described above, the electric actuator 1 is configured as an actuator that drives the moving blade 102. As shown in FIG. 3, the electric actuator 1 includes a housing 2, a screw mechanism 10, a first electric motor 5, a relief mechanism 20, and the like. In the following, for convenience of explanation, in each drawing, the direction indicated by the arrow described as “front” is referred to as “front side or front”, and the direction indicated by the arrow described as “rear” is referred to as “rear side or rear”.

  The housing 2 is provided as a structure having an internal space. In the present embodiment, the housing 2 is constituted by two members. Specifically, the housing 2 includes a first housing portion 3 (cylindrical housing portion) and a second housing portion 4 (base side housing portion), which are combined with each other. The two housing parts 3 and 4 cannot be displaced with respect to each other by a pair of restricting pins 25 and 26 described later in detail.

The first housing part 3 is provided as a cylindrical housing part formed in a substantially cylindrical shape. A concave portion 3 a in which the stator 6 of the first electric motor 5 is disposed is formed in the front portion of the inner periphery of the first housing portion 3. On the other hand, on the rear side of the first housing part 3, two first holes H _1A and H _1B (first engaging parts) that penetrate the first housing part 3 in the thickness direction (radial direction) are formed. ing. The two first holes H _1A and H _1B are formed at positions different by 180 degrees in the circumferential direction of the first housing part 3.

  The second housing part 4 is provided as a base side housing part which is a separate member from the first housing part 3. As described above, the second housing portion 4 is connected to the blade 101, which is an installation location of the electric actuator 1, via a rotating shaft.

The second housing part 4 includes a second housing cylindrical part 4a formed in a cylindrical shape whose front part is accommodated in the first housing part 3, and a bottom part 4b provided at a rear end part of the second housing cylindrical part 4a. These are integrally formed. On the rear side of the second housing cylindrical portion 4a, two second holes H _2A and H _2B (second engaging portions) that penetrate the second housing cylindrical portion 4a in the thickness direction (radial direction) are formed. ing. The second holes H _2A and H _2B are formed at the same positions as the corresponding first holes H _1A and H _{1B in} the axial direction and the circumferential direction of the second housing part 4. That is, the second hole portions H _2A and H _2B are formed at positions overlapping the corresponding first hole portions H _1A and H _1B when viewed from the radially outer side of the second housing portion 4. Thereby, 1st hole H _1A and 2nd hole H _2A , 1st hole H _1B, and 2nd hole H _2B are arranged along the radial direction of each housing part 3 and 4, respectively. .

  The first electric motor 5 is used as a drive source for driving the moving blade 102 which is a relatively heavy device. Therefore, a motor having a relatively high rated voltage (for example, a motor having a rated voltage of 270 V) is used as the first electric motor 5.

  The first electric motor 5 is a so-called inner rotor type electric motor configured such that a rotor disposed inside the stator rotates relative to a substantially annular stator. The first electric motor 5 has a stator 6 and a rotor 7. The stator 6 is formed in a substantially annular shape. A portion of the stator 6 on the outer peripheral side is fitted into a recess 3 a formed in the first housing portion 3. The rotor 7 is formed in a substantially annular shape having an outer diameter smaller than the inner diameter of the stator 6, and is accommodated in the stator 6 in a state spaced from the stator 6 in the radial direction. The first electric motor 5 is configured such that the rotor 7 is rotated by a rotating magnetic field generated in the stator 6 by a current flowing through a winding (not shown) wound around the stator 6.

  The screw mechanism 10 is provided as a mechanism that converts the rotational driving force output by the first electric motor 5 into a linear driving force and outputs the linear driving force. As shown in FIG. 3, the screw mechanism 10 includes a first screw 11, a second screw 12, a plurality of balls 13, and the like. In the present embodiment, the second screw 12 is provided as an input side screw to which the rotational force from the first electric motor 5 is input. The first screw 11 is provided with an output portion 11 b and is provided as an output side screw that advances and retreats in the axial direction by the rotational force of the second screw 12.

  The second screw 12 is formed in a substantially cylindrical shape. The second screw 12 is inserted into the inner periphery of the rotor 7 of the first electric motor 5 and integrated with the rotor 7. The second screw 12 is rotatably held by the first housing portion 3 via bearings 8a attached to both ends in the axial direction of the second screw 12. That is, when the first electric motor 5 is driven and the rotor 7 rotates, the second screw rotates together with the rotor 7 with respect to the first housing portion 3 via the bearing 8a. A spiral thread groove 12 a is formed on the inner peripheral surface of the second screw 12.

  The first screw 11 is provided as an axial member extending along the axial direction of the first housing part 3. The first screw 11 has a first screw cylindrical portion 11a that is a cylindrical portion provided in a rear portion, and a protruding portion that protrudes forward from the cylindrical portion 11a, and these are integrally formed. Yes. The protruding portion is provided as an output portion 11b that outputs the driving force generated by the electric actuator 1 to the outside. A spiral thread groove 11c is formed on the outer peripheral surface of the first screw cylindrical portion 11a.

  A portion on the front side of the second housing cylindrical portion 4a is accommodated inside the first screw cylindrical portion 11a so as to be concentric with the axis of the first screw 11. And between the inner side of the 1st screw cylinder part 11a and the outer side of the 2nd housing cylinder part 4a, the 1st screw 11 cannot be rotated with respect to the 2nd housing part 4, and it is the front-back direction (axis of the 1st screw 11). A ball spline mechanism 15 is provided as a slide support mechanism that is displaceably supported in the center direction). The slide support mechanism may be configured by a mechanism other than the ball spline mechanism 15 as long as it is a mechanism that supports the first screw with respect to the second housing part 4 so as not to rotate and to be displaceable in the front-rear direction. . For example, as an example, the slide support mechanism may be configured by a spline mechanism. As another example, the slide support mechanism includes: a detent that prevents the first screw from rotating relative to the second housing; and a slide bearing that supports the first screw so as to be displaceable in the axial direction. It may be configured.

  A plurality of balls 13 are configured to circulate between the thread groove 12 a on the inner periphery of the second screw 12 and the thread groove 11 c of the first screw 11. That is, the screw mechanism 10 is configured as a ball screw mechanism.

  In the screw mechanism 10, when the first electric motor 5 is driven, the second screw 12 rotates together with the rotor 7. As a result, the plurality of balls 13 roll between the thread groove 11 c of the first screw 11 and the thread groove 12 a of the second screw 12. As a result, the first screw 11 is displaced in the axial direction of the second screw 12.

[Relief mechanism]
4 is an enlarged view of the vicinity of the relief mechanism 20 in FIG. The relief mechanism 20 is a mechanism that allows the output portion 11b to be separated from the blade 101 and moved forward and backward when the screw mechanism 10 is in a fixed state (jammed state) due to a twist or seizure. As shown in FIG. 4, the relief mechanism 20 includes a second electric motor 21 (a regulating member driving unit), an output shaft 22, a pair of nut members 23 and 24, a link mechanism 30, a pair of regulating pins 25, 26 (regulating member).

  The second electric motor 21 is for operating the link mechanism 30. The second electric motor 21 is attached to the bottom part 4 b of the second housing part 4. Note that the second electric motor 21 is not for driving a device that is as heavy as the moving blade 102 that is the driving target of the first electric motor 5, and thus does not require as much power. As the second electric motor 21, for example, a motor having a rated voltage of about 24V is used as an example.

  The output shaft 22 is provided as an output shaft for transmitting the rotational force of the second electric motor 21. The output shaft 22 is provided inside the second housing part 4 so as to be concentric with the axis of the second housing part 4.

  A male thread portion is formed on the outer peripheral surface of the output shaft 22. Specifically, the output shaft 22 has a first male screw portion 22a formed on one side (the rear side in FIG. 4) of the output shaft 22, and the other side of the output shaft 22 (the front side in FIG. 4). ) Is formed with a second male screw portion 22b.

  The first male screw portion 22a and the second male screw portion 22b are in a reverse screw relationship with each other. That is, when one male screw part 22a, 22b is comprised by the right screw, the other male screw part 22b, 22a is comprised by the left screw.

  The pair of nut members 23 and 24 includes a first nut member 23 and a second nut member 24. The first nut member 23 is formed with a first female screw portion 23a, and the second nut member 24 is formed with a second female screw portion 24a.

  The first nut member 23 is screwed to the first male screw portion 22 a of the output shaft 22, and the second nut member 24 is screwed to the second male screw portion 22 b of the output shaft 22. That is, the first female screw portion 23a of the first nut member 23 and the second female screw portion 24a of the second nut member 24 are in a reverse screw relationship.

  The link mechanism 30 includes a plurality of (four in the present embodiment) link members 31, 32, 33, and 34, which are provided so as to be swingable with respect to each other. More specifically, the link mechanism 30 is arranged in a quadrangular shape with the ends of the four link members 31, 32, 33, 34 being overlapped with each other so that each end can be swung by a connecting pin. Are connected to each other.

  Specifically, the link mechanism 30 includes a first link member 31, a second link member 32, a third link member 33, and a fourth link member 34. Each link member 31 to 34 is formed in an elongated plate shape.

  One end of the first link member 31 is swingably connected to the first nut member 23 by a connecting pin 35, while the other end is swingable to a first regulating pin 25 to be described in detail later by a connecting pin 36. Connected. One end side of the second link member 32 is swingably connected to the second nut member 24 by a connecting pin 37, while the other end side swings to the first restriction pin 25 together with the first link member 31 by a connecting pin 36. Connected freely. One end side of the third link member 33 is pivotally connected to the first nut member 23 together with the first link member 31 by a connecting pin 35, while the other end side is connected to the first nut member 23 by a connecting pin 38. The pin 26 is swingably connected. One end side of the fourth link member 34 is swingably connected to the second nut member 24 together with the second link member 32 by the connecting pin 37, while the other end side is connected to the second link member 33 together with the third link member 33 by the connecting pin 38. The control pin 26 is swingably connected to the restriction pin 26.

  The first link member 31 and the second link member are provided as a pair of link members that are swingably connected to one end side of the first restriction pin 25. The third link member 33 and the fourth link member 34 are provided as a pair of link members that are swingably connected to one end side of the second restriction pin 26. That is, the link mechanism 30 has two pairs of link members.

  The pair of restriction pins 25 and 26 have a first restriction pin 25 and a second restriction pin 26. Each regulation pin 25, 26 is formed in a rod shape having a predetermined length.

The first restricting pins 25 are provided so as to extend along the arrangement direction (the radial direction of the housing portions 3 and 4) of the corresponding two hole portions (the first hole portion H _1A and the second hole portion H _2A ). ing. The first restricting pin 25 is housed in the second housing part 4 at one end, and the other end of the first link member 31 and the other end of the second link member 32 are connected to the one end. 36 is swingably connected.

The second restricting pins 26 are provided so as to extend along the arrangement direction of the two corresponding holes (the first hole H _1B and the second hole H _2B ) (the radial direction of the housing parts 3 and 4). ing. The second restriction pin 26 is housed in the second housing portion 4 at one end side, and the other end side of the third link member 33 and the other end side of the fourth link member 34 are connected to the one end side portion. 38 is swingably connected.

The first restricting pin 25 and the second restricting pin 26 have portions on the other end side of the corresponding first hole portions H _1A and H _1B and second hole portions H _2A and H _2B when the electric actuator 1 is in normal operation. It is in a state inserted through both. On the other hand, the first restriction pin 25 and the second restriction pin 26 will be described in detail later, but when the screw mechanism 10 is in a fixed state and the relief mechanism 20 is activated, only the corresponding second holes H _2A and H _2B are provided. It will be in the state inserted in. That is, in the electric actuator 1, the pair of regulation pins 25 and 26 are inserted into at least the second holes H _2A and H _2B formed in the second housing part 4. Accordingly, the link mechanism 30 that is swingably connected to the pair of restriction pins 25 and 26 and the pair of nut members 23 and 24 that are swingably connected to the link mechanism 30 are , 26 is not rotatable with respect to the second housing part 4.

In the electric actuator 1, the pair of nut members 23 and 24 are close to each other during normal operation (basic operation) (see FIGS. 3 and 4). At this time, the pair of regulation pins 25 and 26 are pushed out by the link mechanism 30 outward in the radial direction of the housing portions 3 and 4. In this state, the part on the other end side of the first restriction pin 25 is in a state of penetrating the first hole H _1A and the second hole H _2A , and the part on the other end side of the second restriction pin 26 However, it has penetrated the 1st hole _H1B and the 2nd hole _H2B . Thereby, at the time of normal operation of the electric actuator 1, the first housing part 3 and the second housing part 4 are connected so that they cannot be displaced relative to each other.

[Basic operation of electric actuator]
Next, the basic operation of the electric actuator 1 according to this embodiment will be described. During the basic operation of the electric actuator 1, the first housing portion 3 and the second housing portion 4 are in a state where they cannot be displaced relative to each other by the pair of restriction pins 25 and 26. (See FIGS. 3 and 4).

  When the electric actuator 1 is operated, the first electric motor 5 is rotationally driven. Then, the 2nd screw 12 fixed to the inner periphery of the rotor 7 rotates. If it does so, since the rotational force of the 2nd screw 12 is transmitted to the 1st screw 11 connected with the ball screw mechanism, the 1st screw 11 (namely, output part 11b) will displace along an axial center direction. Thereby, the moving blade 102 can be driven with respect to the blade 101.

[Operation of the bearing holding release mechanism in the fixed state]
Next, the operation of the electric actuator 1 when the screw mechanism 10 is stuck, particularly the operation of the relief mechanism 20 will be described. For example, in the middle of the operation in which the first screw 11 protrudes or contracts with respect to the housing 2, an operation in which the first screw 11 is displaced in the axial direction with respect to the second screw 12 when a fixed state occurs in the screw mechanism 10. However, it becomes impossible. In this case, in the moving blade control controller (not shown), the occurrence of the fixed state of the screw mechanism 10 is detected, the operation of the first electric motor 5 is stopped, and the relief mechanism 20 is operated.

  Note that, as described above, in the middle of the operation in which the second screw 12 protrudes or contracts with respect to the housing 2, when a fixed state occurs in the screw mechanism 10, the moving blade 102 is It stands up to some extent. Further, since the displacement operation in the axial direction of the first screw 11 with respect to the second screw 12 is impossible, the output portion 11 b cannot be advanced or retracted with respect to the housing 2 by the normal operation of the electric actuator 1.

  However, as described above, when the occurrence of the fixed state of the screw mechanism 10 is detected, the relief mechanism 20 operates based on a command from the moving blade control controller. Specifically, when the occurrence of the fixed state is detected, the second electric motor 21 is driven. At this time, the second electric motor 21 rotates in a predetermined direction in which the first nut member 23 moves rearward. Specifically, for example, when the first male threaded portion 22a of the output shaft 22 and the female threaded portion 23a of the first nut member 23 are composed of right-hand screws, the output shaft 22 is rotated clockwise (clockwise). Rotate.

As described above, when the output shaft 22 rotates, the first nut member 23 moves rearward. As a result, the first restriction pin 25 is pulled by the first link member 31 to move inward in the radial direction of the second housing portion 4, and the second restriction pin 26 is pulled by the third link member 33, thereby 2 Moves radially inward of the housing part 4. Then, the regulation pins 25 and 26 that have penetrated both the first holes H _1A and H _1B and the second holes H _2A and H _2B are both removed from the first holes H _1A and H _1B . It will be in the state which penetrated only 2nd hole _H2A , _H2B .

  On the other hand, when the output shaft 22 rotates in a predetermined direction as described above, the second nut member 24, which has a reverse screw relationship with the first nut member 23, moves in the opposite direction (forward) to the first nut member 23. Thus, the first restriction pin 25 is moved radially inward of the second housing part 4 by being pulled by the second link member 32, and the second restriction pin 26 is pulled by the fourth link member 34 to be 2 Moves radially inward of the housing part 4.

  That is, as the output shaft 22 rotates in the predetermined direction, each of the restriction pins 25 and 26 is pulled in the front-rear direction by a pair of corresponding link members 31, 32, 33, 34. The second housing part 4 moves inward in the radial direction. Thereby, the engagement of the first housing part 3 with respect to the second housing part 4 is released. As a result, the first screw 11 and the second screw 12 that are fixed and integrated with each other are slidable in the axial direction with respect to the second housing part 4 together with the first housing part 3. That is, the output part 11 b is in a state of being slidable in the axial direction with respect to the second housing part 4 connected to the blade 101.

[Operation of bearing retention release mechanism during overload]
In the electric actuator 1, the relief mechanism 20 performs the same operation as described above even when an excessive load is applied to the output unit 11b (when the output unit 11b is overloaded). Specifically, when an overload of the output unit 11b is detected, the operation of the first electric motor 5 is stopped and the second electric motor 21 is driven in the same manner as described above. When the second electric motor 21 is driven, the pair of restricting pins 25 and 26 move radially inward as described above, thereby disengaging the first housing part 3 from the second housing part 4. The As a result, the output part 11b is slidable in the axial direction with respect to the second housing part 4. Thereby, it is possible to prevent the screw mechanism 10 and the like from being damaged in the electric actuator 1 due to an excessive load acting on the output unit 11b.

[effect]
As described above, in the electric actuator 1 according to this embodiment, when the second screw 12 is driven to rotate by the first electric motor 5, the first screw 11 rotates relative to the second screw 12. Relative displacement in the axial direction. Thereby, the output part 11b can be displaced so that it may expand and contract along the linear direction (axial direction) with respect to the housing 2, and the moving blade 102 connected to the output part 11b can be driven.

In the electric actuator 1, when the screw mechanism 10 is fixed (jammed) and the first screw 11 and the second screw 12 are relatively unrotatable, the electric actuator 1 is connected to the output unit 11b. The moving blade 102 can be prevented from being fixed in that state. Specifically, in this configuration, when the fixed state occurs, the second electric motor 21 is driven. Then, the pair of restricting pins 25 and 26 inserted across both the corresponding first hole portions H _1A and H _1B and the second hole portions H _2A and H _2B are formed into the first hole portions H _1A and H _1B. Extracted from. Then, relative movement of the first housing part 3 with respect to the second housing part 4 is allowed. In other words, the first housing part 3 on the side connected to the moving blade 102 to be driven is axially oriented with respect to the second housing part 4 attached to the blade 101 which is the installation location of the electric actuator 1. Can be displaced freely. Thereby, the 1st screw 11 and the 2nd screw 12 of the state integrated by the adhering state become displaceable with respect to the wing | blade 101 in the axial center direction of a screw.

  Therefore, in the electric actuator 1, the output portion 11 b can be made to be able to advance and retreat with respect to the wing 101 even when the screw mechanism 10 is stuck. Therefore, as an example, it is possible to attach an actuator different from the electric actuator 1 to the moving blade 102 and operate the moving blade 102 by the actuator. Furthermore, the structure for enabling the output portion 11b to advance and retreat as described above is realized by a relatively small and simple structure that includes the restriction pins 25 and 26, the second electric motor 21, and the like. For this reason, simplification and size reduction of the structure of the electric actuator 1 are achieved.

  Therefore, according to the electric actuator 1, the output portion 11 b can be advanced and retracted with respect to the second housing portion 4 connected to the blade 101 even when the screw mechanism 10 is stuck. In addition, it is possible to provide an electric actuator that can be simplified and downsized.

  Further, in the electric actuator 1, even if an overload occurs in the electric actuator 1, the relief mechanism 20 can be operated in the same manner as described above. Thereby, it is possible to prevent the screw mechanism 10 and the like from being damaged in the electric actuator 1 due to an excessive load acting on the output unit 11b.

  Further, in the electric actuator 1, in the configuration in which the second screw 12 is provided as the input side screw, it is possible to provide a configuration in which the output portion 11 b can be advanced and retracted with respect to the second housing portion 4 when the screw mechanism 10 is fixed. .

  In the electric actuator 1, the output portion 11 b can be slid in the axial direction with respect to the second housing portion 4 by the ball spline mechanism 15 when the screw mechanism 10 is fixed. Moreover, the ball spline mechanism 15 includes an inner side of the first screw cylindrical portion 11a, more specifically, the first screw cylindrical portion 11a and the second housing portion 4 partially accommodated in the first screw cylindrical portion 11a. Formed between. Thereby, the enlargement of the electric actuator 1 can be suppressed.

Moreover, in the electric actuator 1, when the screw mechanism 10 is fixed, each regulation pin 25 in a state of being inserted across both the corresponding first holes H _1A and H _1B and the second holes H _2A and H _2B. , 26 are removed from the first holes H _1A , H _1B , the relief mechanism 20 operates.

Specifically, in the relief mechanism 20, when the output shaft 22 of the second electric motor 21 is rotationally driven in a predetermined direction, the nut members 23 and 24 screwed to the output shaft 22 are moved in the axial direction. It moves in a direction away from the regulation pins 25 and 26. Then, the link member 31, 32, 33, 34 whose one end side is swingably connected to the nut members 23, 24 is swingably connected to the other side of the link member 31, 32, 33, 34. The pins 25 and 26 are pulled inward in the radial direction of the second housing part 4. Thereby, the control pins 25 and 26 in a state of being inserted across both the first holes H _1A and H _1B and the second holes H _2A and H _2B are removed from the first holes H _1A and H _1B. It can be made the state. Thereby, when the screw mechanism 10 is fixed, the engagement of the first housing part 3 with respect to the second housing part 4 is released, and the output part 11b is advanced and retracted in the axial direction with respect to the second housing part 4. It becomes possible.

  Further, in the electric actuator 1, components such as nut members 23 and 24 and link members 31, 32, 33, and 34 that constitute a part of the relief mechanism 20 are accommodated inside the second housing portion 4. Thereby, the enlargement of the electric actuator 1 can be suppressed.

  Further, in the electric actuator 1, when the output shaft 22 of the second electric motor 21 rotates in a predetermined direction, the pair of nut members 23 and 24 screwed to the output shaft 22 are respectively restricted in the axial direction. It moves in a direction away from the pins 25, 26, that is, in a direction away from each other. Then, a pair of link members 31, 32, 33, 34 whose one end sides are swingably connected to the nut members 23, 24 are commonly connected to the pair of link members 31, 32, 33, 34. The regulation pins 25 and 26 are pulled inward in the radial direction of the second housing part 4. That is, since the restriction pins 25 and 26 can be advanced and retracted by the pair of link members 31, 32, 33, and 34, the restriction pins 25 and 26 can be reliably operated.

  Further, in the electric actuator 1, the first housing portion 3 and the second housing portion 4 can be engaged by the plurality of restriction pins 25 and 26, so that the two housing portions 3 and 4 are securely engaged. can do.

  Moreover, the 2nd electric motor 21 provided in the relief mechanism 20 can be comprised with the motor which can be driven with comparatively small power. Therefore, for example, the electric power of the second electric motor 21 can be supplied from an auxiliary power source such as a battery, so that the second electric motor 21 can be driven relatively easily even in a situation where the use environment of the power source is limited.

  Although the embodiments of the present invention have been described above, 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, you may implement the following modifications.

(1) FIG. 6 is an enlarged view of the vicinity of the relief mechanism 20 in the electric actuator according to the modification. In the above embodiment, the first engagement portion, the first hole portion H _1A is a _{through-hole,} was constructed in an H _1B, not limited to this, as shown in FIG. 6, the first engagement portion, recess You may comprise by part _H1C , _H1D .

  (2) FIG. 7 is an enlarged view of the vicinity of the relief mechanism 20a in the electric actuator according to the modification. In the above embodiment, the two housing parts 3 and 4 are engaged with each other by the pair of restriction pins 25 and 26. However, the present invention is not limited to this, and as shown in FIG. The housing parts 3 and 4 may be engaged with each other. Thereby, compared with the case of the said embodiment, a structure can be simplified.

  (3) FIG. 8 is an enlarged view of the vicinity of the relief mechanism 20b in the electric actuator according to the modification. In the above embodiment, the restriction pins 25 and 26 are advanced and retracted by the pair of link members 31, 32, 33 and 34. However, the present invention is not limited to this, and as shown in FIG. May be advanced or retracted. Thereby, compared with the case of the said embodiment, a structure can be simplified.

  (4) In the said embodiment, although the control member was comprised with the rod-shaped control pin, you may form not only this but a control member in plate shape or block shape.

  (5) In the above embodiment, the restriction pin 25 is advanced and retracted using the link mechanism 30, but this is not restrictive. For example, a mechanism for advancing and retracting the restriction pin may be configured by appropriately selecting a gear, a cam, or the like, or appropriately combining them.

  (6) Although the screw mechanism 10 having the two screws 11 and 12 has been described as an example in the embodiment described above as a ball screw mechanism, this need not be the case. That is, the screw mechanism having the first and second screws may be implemented as a configuration having a configuration other than the ball screw mechanism. For example, a screw mechanism configured to screw the first screw and the second screw may be implemented. Or the screw mechanism which has a 1st and 2nd screw may be implemented as a form provided with the structure of the roller screw mechanism. In the case of the roller screw mechanism, a plurality of screw-like roller shafts each having a spiral groove on the outer periphery are rotatably installed between the first screw and the second screw. As the first screw or the second screw rotates, each roller shaft meshes with the first screw and the second screw in a spiral groove and rotates around each axis.

  (7) In the above embodiment, the input side screw is constituted by the second screw 12 and the output side screw is constituted by the first screw 11. However, the present invention is not limited to this, and the input side screw is constituted by the first screw and the output. You may comprise a side screw with a 2nd screw.

  The present invention can be widely applied to an electric actuator that has a screw mechanism and converts a rotational driving force output by an electric motor into a linear driving force and outputs the linear driving force.

DESCRIPTION OF SYMBOLS 1 Electric actuator 2 Housing 3 1st housing part (tubular housing part)
4 Second housing part (base side housing part)
DESCRIPTION OF SYMBOLS 5 1st electric motor 10 Screw mechanism 11 1st screw mechanism 11b Output part 12 2nd screw mechanism 20, 20a, 20b Relief mechanism 21 Control member drive part (2nd electric motor)
H _1A , H _1B first hole (first engaging portion)
H _1C , H _1D dent (first engagement part, dent)
H _2A , H _2B second hole (second engaging portion)

Claims (6)

A housing having a cylindrical housing part formed in a cylindrical shape, and a base side housing part provided as a separate member from the cylindrical housing part;
A first screw that is at least partially housed in the cylindrical housing portion; and a cylindrical portion in which the first screw is installed inside, and the shaft of the first screw with respect to the first screw. A screw mechanism having a second screw which is attached so as to be rotatable relative to the center and which can be relatively displaced in the axial direction of the first screw by rotating relative to the first screw;
A first electric motor that is provided as one of the first screw and the second screw and rotates an input side screw that is rotatably supported with respect to the cylindrical housing portion;
An output unit connected or provided to an output side screw provided as the other screw of the first screw and the second screw;
A through hole formed in one of the cylindrical housing part and the base side housing part or a first engagement part as a recess, and a through hole formed in the other of the cylindrical housing part and the base side housing part A restricting member that restricts relative movement of the cylindrical housing part with respect to the base-side housing part by being inserted across both of the second engaging parts, and the restricting member in the first engagement A relief mechanism having a regulating member driving part that allows relative movement of the cylindrical housing part with respect to the base-side housing part by removing from at least one of the part and the second engaging part,
An electric actuator comprising: The electric actuator according to claim 1,
The first electric motor is
A stator portion formed in a substantially annular shape and fixed to the cylindrical housing portion so as to be concentric with the cylindrical housing portion;
A substantially annular rotor portion housed in the stator portion and rotating with respect to the stator portion;
The electric actuator, wherein the second screw as the input side screw is fixed inside the rotor portion. The electric actuator according to claim 2,
The first screw as the output-side screw has a first screw cylindrical portion that opens toward the axial direction at a portion opposite to the output portion in the axial direction of the first screw,
The base side housing part is formed in a cylindrical shape, and is housed in the first screw cylindrical part so that a portion on one side in the axial direction is concentric with the axial center of the first screw cylindrical part,
A slide that restricts rotation of the first screw relative to the base side housing portion and allows sliding of the first screw relative to the base side housing portion between the first screw cylindrical portion and the base side housing portion. An electric actuator, further comprising a support mechanism. The electric actuator according to claim 3, wherein
The second electric motor provided as the restricting member drive unit is configured so that the output shaft of the second electric motor is accommodated in the base side housing portion so as to be along the axis of the base side housing portion. Fixed to the side housing part,
The first engagement portion is formed in the cylindrical housing portion, while the second engagement portion is formed in the base side housing portion,
The restricting member is formed in a rod shape that advances and retreats along the arrangement direction of the first engaging portion and the second engaging portion, and one end side is configured as a restricting pin that is accommodated in the base side housing portion,
The relief mechanism includes a nut member formed with a female screw portion that is screwed into a male screw portion formed on the outer periphery of the output shaft of the second electric motor, and one end side of which is swingable with respect to the nut member. A link member that is connected to the one end side of the restriction pin so that the other side is swingable, and the restriction pin is connected to the first engagement portion and the second engagement portion. An electric actuator configured to be in a state in which the restricting pin is removed from the first engaging portion by rotational driving of the output shaft from a state where it is inserted across both . The electric actuator according to claim 4,
The relief mechanism is
A pair of male screw portions formed on the one side portion and the other side portion in the axial direction on the outer peripheral surface of the output shaft, and having a reverse screw relationship with each other,
A pair of nut members each having a female screw portion that is screwed into each male screw portion;
A pair of link members each having one end side pivotably connected to each nut member, and each other end side pivotably connected to the one end side of the restriction pin ,
The electric actuator characterized by having. The electric actuator according to claim 5, wherein
Two said first engaging parts are formed in the said cylindrical housing part,
Two second engaging portions arranged on the base side housing portion so as to overlap each of the corresponding two first engaging portions in the radial direction of the cylindrical housing portion. Formed,
Each of the relief mechanisms has a pair of restriction pins that are inserted across both the corresponding first engaging portion and the second engaging portion,
2. The electric actuator according to claim 1, wherein the relief mechanism includes two pairs of link members that are swingably connected to the one end side of each of the restriction pins.

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