WO2017169935A1 - Actionneur électrique - Google Patents

Actionneur électrique Download PDF

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Publication number
WO2017169935A1
WO2017169935A1 PCT/JP2017/011060 JP2017011060W WO2017169935A1 WO 2017169935 A1 WO2017169935 A1 WO 2017169935A1 JP 2017011060 W JP2017011060 W JP 2017011060W WO 2017169935 A1 WO2017169935 A1 WO 2017169935A1
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WO
WIPO (PCT)
Prior art keywords
electric actuator
rotor
axial direction
nut member
screw shaft
Prior art date
Application number
PCT/JP2017/011060
Other languages
English (en)
Japanese (ja)
Inventor
卓志 松任
池田　良則
悠紀 内藤
Original Assignee
Ntn株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ntn株式会社 filed Critical Ntn株式会社
Publication of WO2017169935A1 publication Critical patent/WO2017169935A1/fr

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/50—Other types of ball or roller bearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
    • F16C35/08—Rigid support of bearing units; Housings, e.g. caps, covers for spindles
    • F16C35/12—Rigid support of bearing units; Housings, e.g. caps, covers for spindles with ball or roller bearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H25/00—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms
    • F16H25/18—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms for conveying or interconverting oscillating or reciprocating motions
    • F16H25/20—Screw mechanisms
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H25/00—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms
    • F16H25/18—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms for conveying or interconverting oscillating or reciprocating motions
    • F16H25/20—Screw mechanisms
    • F16H25/22—Screw mechanisms with balls, rollers, or similar members between the co-operating parts; Elements essential to the use of such members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H25/00—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms
    • F16H25/18—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms for conveying or interconverting oscillating or reciprocating motions
    • F16H25/20—Screw mechanisms
    • F16H25/24—Elements essential to such mechanisms, e.g. screws, nuts
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/06—Means for converting reciprocating motion into rotary motion or vice versa

Definitions

  • the present invention relates to an electric actuator.
  • the electric actuator of Patent Document 1 has a planetary gear speed reducer as a speed reducer, and the output of the motor is transmitted to the nut member of the screw mechanism after being decelerated by the planetary gear speed reducer.
  • a small motor can be employed, there is an advantage that the electric actuator can be reduced in weight and size as a whole.
  • the axial position of the screw shaft (the amount of displacement in the axial direction) can be accurately grasped in order to realize a highly reliable electric actuator with excellent operation accuracy of the screw shaft.
  • the operation control of the output member of the actuator can be performed based on the axial position of the screw shaft.
  • the electric actuator of Patent Document 1 the axial direction outside of the motor (on the side opposite to the side where the planetary gear reducer is arranged), the radial outside of the screw shaft, and the axial direction of the screw shaft.
  • a displacement sensor for detecting the amount of displacement is provided.
  • the electric actuator has a plurality of (two) operation objects, such as DCT (Dual Clutch Transmission), which is a kind of automatic transmission, and the two operation objects are arranged coaxially. Also applies.
  • the electric actuator of Patent Document 1 is not considered at all for application to a device having a plurality of operation objects as described above (biaxial output shaft). Therefore, when applying the electric actuator of Patent Document 1 to a device having two operation objects, for example, two electric actuators are individually installed, and the connection mode between the output member of each electric actuator and the operation object is devised. Therefore, there is a possibility of increasing the size and complexity of the entire device.
  • the main problem of the present invention is that it is compact in the axial direction and excellent in mountability to the equipment used, and it is easy to improve the operation accuracy of the output member or to request the biaxial output member.
  • An object of the present invention is to provide a versatile electric actuator that can be used.
  • the present invention which was created to solve the above problems, includes a motor unit that is driven by power supply, and a motion conversion mechanism unit that converts the rotational motion of the motor unit into a linear motion and outputs the motion.
  • the conversion mechanism unit includes a reduction gear that decelerates and outputs the rotation of the rotor of the motor unit, a screw shaft that is arranged coaxially with the rotation center of the rotor, and a nut member that is rotatably fitted to the outer periphery thereof.
  • the rotor In the electric actuator in which the screw shaft linearly moves in the axial direction along with the rotation of the nut member, the rotor is mounted on the outer periphery of the rotor core holding the rotor magnet, and can transmit torque to the output member of the reducer And a hollow rotary shaft having a connected nut member disposed on the inner periphery, and the screw shaft is formed in a hollow shape having through holes opened on both end faces in the axial direction.
  • the “reduction gear” here is a concept including various reduction devices such as a planetary gear reduction device and a spur gear reduction device.
  • the electric actuator can be made compact in the axial direction.
  • the screw shaft has through holes that are open on both end faces in the axial direction, the through hole is used as an installation space for a stroke detection sensor for detecting the axial displacement of the screw shaft, or It can be utilized as a part through which an output member (output shaft) of another electric actuator is inserted. If a stroke detection sensor is installed in the above-mentioned through hole, it is not necessary to provide a separate installation space for the stroke detection sensor on the outside of the motor in the axial direction. It is possible to realize an electric actuator excellent in the above.
  • the output member of the reducer is connected to the inner peripheral surface of the rotor and the outer periphery of the nut member.
  • a cylindrical portion interposed between the cylindrical portion, the outer peripheral surface of the cylindrical portion is opposed to the inner peripheral surface of the rotor via a radial clearance, and the inner peripheral surface of the cylindrical portion is fixed to the outer peripheral surface of the nut member Can be adopted. At this time, if the inner peripheral surface of the cylindrical portion is fixed to the outer peripheral surface of the nut member by press-fitting, assembly of the electric actuator can be improved.
  • the hollow rotating shaft constituting the rotor of the motor unit can be rotatably supported by rolling bearings arranged at two locations separated in the axial direction.
  • the hollow rotary shaft is provided with the inner raceway surface of one of the two rolling bearings, the hollow rotary shaft and thus the rotor can be made compact in the axial direction.
  • the electric actuator can be made more compact in the axial direction.
  • the electric actuator can be made more compact in the axial direction if the inner raceway surface is disposed inside the axial width of the nut member.
  • the nut member can be fitted to the outer periphery of the screw shaft via a plurality of balls. That is, the screw mechanism that constitutes the motion conversion mechanism may be a so-called ball screw mechanism. In this way, the operability of the screw shaft and thus the output shaft of the electric actuator can be enhanced.
  • the electric actuator having the above-described configuration includes a plurality of members coupled in the axial direction, and includes a housing that houses the motor unit and the motion conversion mechanism unit, and a terminal unit that holds a power feeding circuit for supplying power to the motor unit. Further, it can be provided. In this case, the assembling property of the electric actuator can be improved by sandwiching the terminal portion from both sides in the axial direction by the constituent members of the casing.
  • the terminal portion may have an opening for pulling out a lead wire connected to the power feeding circuit to the outer diameter side of the casing on the outer peripheral portion thereof.
  • a lead wire connected to the power feeding circuit to the outer diameter side of the casing on the outer peripheral portion thereof.
  • FIG. 1 is a longitudinal sectional view of an electric actuator according to an embodiment of the present invention.
  • FIG. 2 is a cross-sectional view taken along line EE in FIG. 1. It is the longitudinal cross-sectional view which took out the rotor and motion conversion mechanism part of the motor, and was expanded.
  • FIG. 5 is a cross-sectional view taken along line FF in FIG. 1. It is a longitudinal cross-sectional view which shows the state which integrated the ring gear in the casing. It is the longitudinal cross-sectional view which took out the stator and terminal part of the motor, and was expanded.
  • FIG. 2 is a cross-sectional view taken along line GG in FIG. 1.
  • FIG. 2 is a cross-sectional view taken along line HH in FIG. 1.
  • FIG. 10 is a cross-sectional view taken along the line II in FIG. 9. It is a schematic block diagram which shows the control system of the electric actuator of FIG. It is a longitudinal cross-sectional view of the electric actuator which concerns on other embodiment of this invention.
  • FIG. 13 is an enlarged sectional view taken along line JJ in FIG.
  • FIG. 1 is a longitudinal sectional view of an electric actuator according to an embodiment of the present invention
  • FIG. 2 is a sectional view taken along line EE in FIG. 1, and FIG.
  • the longitudinal cross-sectional view which took out and expanded the mechanism part is shown.
  • 1 and 2 show a state where the screw shaft 33 constituting the output member of the electric actuator is located at the origin.
  • the “state positioned at the origin” means that the end surface of the screw shaft 33 (the inner member 36 connected thereto) is opposed to the end surface of the cover 29 by the spring force of the compression coil spring 48 described later. It is the state which exists in the position which contact
  • the electric actuator 1 of the present embodiment includes a motor unit A that is driven by power supply, and a motion conversion that converts the rotational motion of the motor unit A into a linear motion and outputs it.
  • a mechanism part B, an operation part C for operating an operation target not shown, and a terminal part D are provided, and these are accommodated and held in the housing 2.
  • the housing 2 is composed of a plurality of members that are coaxially arranged and coupled in the axial direction.
  • the casing 2 of the present embodiment has an end on one side in the axial direction (the right side in FIG. 1 and FIG. 2), and the other side in the axial direction (the left side in FIG. 1 and FIG. 2).
  • a cover 29 that closes the end opening on the other axial side of the casing 20
  • a terminal that is disposed between the casing 20 and the cover 29 and constitutes the terminal portion D It consists of a combination with the main body 50.
  • the cover 29 and the terminal main body 50 are fixedly attached to the casing 20 by assembly bolts 61 shown in FIGS. Accordingly, the terminal body 50 is sandwiched and fixed between the casing 20 and the cover 29 disposed on both sides in the axial direction.
  • the motor part A includes a radial gap type motor (in detail, a U-phase, a stator having a stator 23 fixed to the casing 20 and a rotor 24 disposed to face the inner periphery of the stator 23 via a radial gap. 3 phase brushless motor having a V phase and a W phase) 25.
  • the stator 23 includes an insulating bobbin 23b attached to the stator core 23a, and a coil 23c wound around the bobbin 23b.
  • the rotor 24 includes a rotor core 24a, a permanent magnet 24b as a rotor magnet attached to the outer periphery of the rotor core 24a, and a rotor inner 26 as a hollow rotating shaft that is formed in a hollow shape and has the rotor core 24a attached to the outer periphery.
  • the rotor core 24 a is fitted to the outer peripheral surface 26 b of the rotor inner 26 after setting the side plate 65 on the shoulder portion 26 a on one axial side of the rotor inner 26.
  • the permanent magnet 24b (see FIG. 2) is fitted to the outer periphery of the rotor core 24a, the side plate 65 attached to the axially outer side of the other end of the rotor core 24a in the axial direction of the rotor inner 26, and its It is positioned and fixed by a circlip 66 attached to the outside in the axial direction.
  • an inner raceway surface 27 a of the rolling bearing 27 is formed on the outer periphery of one end of the rotor inner 26 in the axial direction, and the outer ring 27 b of the rolling bearing 27 is fixed to the inner peripheral surface of the casing 20.
  • the bearing holder 28 is attached to the inner peripheral surface.
  • a rolling bearing 30 is mounted between the inner peripheral surface of the other end in the axial direction of the rotor inner 26 and the outer peripheral surface of the cylindrical portion 29 a of the cover 29.
  • the motion conversion mechanism section B of the present embodiment includes a ball screw device 31 and a planetary gear speed reducer 10 as a speed reducer.
  • the planetary gear speed reducer 10 includes a motor section A. Are arranged adjacent to each other in the axial direction.
  • the ball screw device 31 is arranged coaxially with the rotation center of the rotor 24, and can be rotated on the outer periphery of the screw shaft 33 via a screw shaft 33 constituting an output member (output shaft) of the electric actuator 1 and a plurality of balls 34.
  • a nut member 32 disposed on the inner periphery of the rotor inner 26 so as to be able to transmit torque with the rotor inner 26, and a top 35 as a circulation member.
  • a plurality of balls 34 are loaded between the spiral groove 32a formed on the inner peripheral surface of the nut member 32 and the spiral groove 33a formed on the outer peripheral surface of the screw shaft 33, and the top 35 is incorporated. . With such a configuration, when the screw shaft 33 linearly moves in the axial direction as the nut member 32 rotates, the ball 34 circulates between the spiral grooves 32a and 33a.
  • the screw shaft 33 is formed in a hollow shape having through holes 33b opened on both end faces in the axial direction, and the inner member 36 is accommodated in the through holes 33b.
  • the inner member 36 is made of, for example, a resin material such as PPS, and has a circular solid portion 36a provided at an end portion on one side in the axial direction, a flange portion 36b provided at an end portion on the other side in the axial direction, It has integrally the cylinder part 36c which connects both parts 36a and 36b.
  • the inner member 36 accommodated in the through hole 33b of the screw shaft 33 is connected and fixed to the screw shaft 33 by fitting a pin 37 so as to penetrate the circular solid portion 36a and the screw shaft 33 in the radial direction.
  • the Both end portions of the pin 37 protrude radially outward from the outer peripheral surface of the screw shaft 33, and a guide collar 38 is rotatably fitted on the protruding portion.
  • the guide collar 38 is formed of a resin material such as PPS, for example, and is fitted in an axial guide groove 20b (see also FIG. 5) provided on the inner peripheral surface of the small diameter cylindrical portion 20a of the casing 20.
  • an actuator head 39 as an operation portion C is detachably attached to one end of the screw shaft 33 in the axial direction.
  • the actuator head 39 of this embodiment is a so-called push type in which the tip surface pressurizes the operation target in the axial direction as the screw shaft 33 linearly moves in one axial direction.
  • a so-called push-pull type in which the operation target can be operated on both sides in the axial direction can be adopted.
  • the type and shape of the actuator head 39 to be used is determined according to the equipment used in which the electric actuator 1 is mounted.
  • the planetary gear speed reducer 10 includes a ring gear 40 fixed to the casing 20, a sun gear 41 press-fitted to the inner circumferential surface 26c of the rotor inner 26, and the ring gear 40 and the sun gear 41.
  • a plurality (four in this embodiment) of planetary gears 42 arranged between the two gears 40 and 41, and a planetary gear carrier 43 and a planetary gear holder 44 that rotatably hold the planetary gears 42 are provided.
  • the planetary gear carrier 43 takes out the revolution movement of the planetary gear 42 and outputs it. Accordingly, the planetary gear carrier 43 constitutes an output member of the planetary gear reducer 10.
  • the outer periphery of the ring gear 40 is provided with notches 40 a projecting radially outward at a plurality of locations (four locations in the illustrated example) spaced apart in the circumferential direction.
  • the grooves are fitted in axial grooves 20e (see also FIG. 5) provided at a plurality of locations (four locations in the illustrated example) separated in the circumferential direction of the surface 20c.
  • the planetary gear carrier 43 includes a pin-like portion fitted on the inner periphery of the planetary gear 42, a disc-like portion arranged on one side in the axial direction of the planetary gear 42, and a disc A cylindrical portion 43 a that extends from the radially inner end of the shape portion to the other axial side and is interposed between the inner peripheral surface 26 d of the rotor inner 26 and the outer peripheral surface 32 b of the nut member 32 is integrally provided.
  • the planetary gear carrier 43 is rotatable relative to the rotor inner 26, and is connected to the nut member 32 of the ball screw device 31 so as to be integrally rotatable (torque can be transmitted).
  • the outer peripheral surface of the cylindrical portion 43 a faces the inner peripheral surface 26 d of the rotor inner 26 (and the inner peripheral surface of the sun gear 41) via a radial gap, and the inner peripheral surface of the cylindrical portion 43 a is the nut member 32. It is press-fitted and fixed to the outer peripheral surface 32b.
  • the connection workability during assembly is good. In addition to the above, stable torque transmission is possible even for high torque after deceleration. Further, since the sun gear 41 is press-fitted into the stepped inner peripheral surface 26c of the rotor inner 26, the rotor inner 26 and the sun gear 41 are connected so as to be able to transmit torque. Also in this respect, the connection workability during assembly is good. is there.
  • the sun gear 41 only needs to be able to rotate integrally with the rotor inner 26 before deceleration, and therefore the torque transmission performance required between the two can be sufficiently ensured. Furthermore, since the rotor inner 26 and the sun gear 41 are connected at a position directly below the rolling bearing 27 that supports the rotor inner 26, the rotational accuracy of the sun gear 41 is also good.
  • the rotation of the rotor 24 (rotor inner 26) of the motor 25 is decelerated by the planetary gear speed reducer 10 having the above configuration and then transmitted to the nut member 32. Thereby, since a rotational torque can be increased, the small motor 25 can be employ
  • a thrust washer 45 is disposed between the end face on one axial side of the nut member 32 and the casing 20, and the thrust attached to the outer periphery of the distal end portion of the cylindrical portion 29 a of the cover 29.
  • a needle roller bearing 47 as a thrust bearing is disposed between the receiving ring 46 and the end surface on the other axial side of the nut member 32.
  • a compression coil spring 48 is disposed between the inner peripheral surface 29b of the cylindrical portion 29a of the cover 29 and the outer peripheral surface of the screw shaft 33.
  • the ends of the compression coil spring 48 on one side and the other side in the axial direction are in contact with the needle roller bearing 47 and the flange portion 36b of the screw shaft 33 (the inner member 36 connected to the screw shaft 33).
  • the screw shaft 33 is constantly urged toward the origin by the spring force of the compression coil spring 48 provided in the above manner. In this way, for example, when the drive power is not properly supplied to the motor unit A (motor 25), the screw shaft 33 is automatically returned to the origin, which adversely affects the operation of the operation target (not shown). The possibility can be reduced as much as possible. Further, if the compression coil spring 48 is provided in the above-described manner, an axial pressure can be applied to the nut member 32, resulting in an operation gap provided between the nut member 32 and the screw shaft 33. Response delay can be eliminated, and the operability of the output member of the electric actuator 1 including the screw shaft 33 and the actuator head 39 (operation unit C) can be improved.
  • FIG. 9 is a left side view of FIG. 1, and FIG. 10 is a cross-sectional view taken along the line II in FIG.
  • the cover 29 is formed of a metal material excellent in workability (mass productivity) and thermal conductivity, for example, an aluminum alloy, a zinc alloy, or a magnesium alloy.
  • a cooling fin for increasing the cooling efficiency of the electric actuator 1 may be provided on the outer surface of the cover 29.
  • a bearing mounting surface 63 on which the rolling bearing 30 is mounted and a fitting surface 64 on which the thrust receiving ring 46 is fitted are provided on the outer peripheral surface of the cylindrical portion 29 a of the cover 29. Yes.
  • a through hole (not shown) through which the assembly bolt 61 of the electric actuator 1 is inserted and a mounting bolt for attaching the electric actuator 1 to a device to be used are inserted into the cover 29.
  • a through hole 62 is provided.
  • FIG. 6 is a longitudinal cross-sectional view in which the stator 23 and the terminal portion D of the motor 25 shown in FIG. 1 are taken out and enlarged
  • FIG. 7 is a cross-sectional view taken along the line GG in FIG. 1, and
  • FIG. It is a HH arrow directional cross-sectional view.
  • the terminal portion D is formed of a resin material such as PPS, for example, and includes a short cylindrical portion constituting a part of the housing 2 and an end portion on the other axial side of the short cylindrical portion.
  • a terminal main body 50 integrally having a disk-shaped portion extending radially inward, a bus bar 51 and a disk-shaped printed circuit board 52 screwed to the terminal main body 50 (the disk-shaped portion thereof) are provided.
  • the terminal main body 50 (the short cylindrical portion thereof) is provided for attaching the through-hole 50A through which the assembly bolt 61 shown in FIGS. And a through hole 50B through which the bolt is inserted, and is sandwiched between the casing 20 and the cover 29 by the assembly bolt 61 (see FIGS. 1 and 2).
  • the terminal part D (terminal body 50) collectively holds electrical components such as a power supply circuit for supplying driving power to the motor 25 and various sensors described later.
  • the power feeding circuit connects the coils 23c of the stator 23 to the terminals 51a of the bus bar 51 for each of the U phase, the V phase, and the W phase.
  • the terminal 51 b of 51 and the terminal block 50 a of the terminal body 50 are fastened with screws 70.
  • the terminal block 50a has a terminal 50b to which a lead wire (not shown) is connected, and the lead wire is an opening 50c (see FIG. 1) provided in the outer peripheral portion (short cylindrical portion) of the terminal body 50. Is pulled out to the outer diameter side of the housing 2 and connected to the controller 81 (see FIG. 11) of the control device 80.
  • the electric actuator 1 of this embodiment is equipped with two types of sensors, and these two types of sensors are held in the terminal portion D.
  • one of the two types of sensors is a rotation angle detection sensor 53 used for rotation control of the motor 25, and the other is stroke control (detection of displacement in the axial direction) of the screw shaft 33.
  • This is a stroke detection sensor 55 used for As the rotation angle detection sensor 53 and the stroke detection sensor 55, a Hall sensor which is a kind of magnetic sensor is used.
  • the rotation angle detection sensor 53 is attached to a printed circuit board 52, and via a pulsar ring 54 attached to an end on the other axial side of the rotor inner 26 and an axial clearance. Opposed.
  • the rotation angle detection sensor 53 determines the timing for supplying current to each of the U phase, V phase, and W phase of the motor 25.
  • the stroke detection sensor 55 is attached to a belt-like printed board 56 that extends in the axial direction and has an end on the other side in the axial direction connected to the printed board 52. .
  • the printed circuit board 56 and the stroke detection sensor 55 are disposed on the inner periphery of the through hole 33b of the screw shaft 33, more specifically, on the inner periphery of the cylindrical portion 36c of the inner member 36 accommodated in the through hole 33b.
  • a permanent magnet 57 as a target is attached to the inner periphery of the cylindrical portion 36c of the inner member 36 so as to face the stroke detection sensor 55 via a radial gap. Permanent magnets 57 are attached to two locations separated from each other.
  • the stroke detection sensor 55 detects the axial and radial magnetic fields formed around the permanent magnet 57, and calculates the axial displacement amount of the screw shaft 33 based on this.
  • the signal line of the rotation angle detection sensor 53 and the signal line of the stroke detection sensor 55 are both connected to the housing through the opening 50c (see FIG. 1) of the terminal body 50. 2 is pulled out to the outer diameter side and connected to the control device 80 (see FIG. 11).
  • the ring gear 40 is assembled in the casing 20.
  • the rotor 24 of the motor 25 and the subassembly of the motion conversion mechanism B shown in FIG. 3 are inserted into the casing 20.
  • the planetary gear 42 and the ring gear 40 are engaged with each other, the guide collar 38 is fitted into the guide groove 20 b of the casing 20, and the bearing holder 28 is fitted into the inner peripheral surface 20 c of the casing 20.
  • the stator 23 is fitted to the inner periphery of the casing 20 in the subassembly of the stator 23 and the terminal portion D (terminal body 50) of the motor 25 shown in FIG. Are fastened by an assembly bolt 61 (see FIGS. 9 and 10). Thereby, the electric actuator 1 is completed.
  • the operation mode of the electric actuator 1 having the above configuration will be briefly described with reference to FIGS.
  • the ECU calculates a required position command value based on the operation amount.
  • the position command value is sent to the controller 81 of the control device 80, and the controller 81 calculates a motor rotation angle control signal necessary for the position command value and sends this control signal to the motor 25.
  • the screw shaft 33 linearly moves (advances) to one side in the axial direction while being prevented from rotating. At this time, the screw shaft 33 moves forward to a position based on the control signal of the controller 81, and the actuator head 39 fixed to the end portion on the one axial side of the screw shaft 33 operates (pressurizes) an operation target (not shown).
  • the axial position of the screw shaft 33 (the amount of displacement in the axial direction) is detected by the stroke detection sensor 55 as shown in FIG. 11, and the detection signal is sent to the comparison unit 82 of the control device 80. Then, the comparison unit 82 calculates the difference between the detection value detected by the stroke detection sensor 55 and the position command value, and the controller 81 is based on the calculated value and the signal sent from the rotation angle detection sensor 53. A control signal is sent to the motor 25. In this way, the position of the actuator head 39 is feedback controlled. For this reason, when the electric actuator 1 of this embodiment is applied to, for example, shift-by-wire, the shift position can be reliably controlled.
  • the electric power for driving the motor 25, the sensors 53, 55, etc. is supplied from an external power source (not shown) such as a battery provided on the vehicle side to a power supply circuit held in the control device 80 and the terminal portion D. Via the motor 25 and the like.
  • the nut member 32 of the ball screw device 31 constituting the motion conversion mechanism B is the inner periphery of the rotor 24 (rotor inner 26 as a hollow rotating shaft). And is connected to the planetary gear carrier 43 that is an output member of the planetary gear speed reducer 10 so that torque can be transmitted.
  • the motor, the planetary gear reducer, and the nut member are arranged continuously in the axial direction.
  • the axial dimension L (see FIG. 1) of the housing 2 can be shortened, that is, the electric actuator 1 can be made compact in the axial direction. Therefore, in particular, it is possible to realize the electric actuator 1 that is excellent in mountability with respect to the used equipment in which the axial dimension of the installation space of the electric actuator 1 is limited.
  • the radial dimension M (see FIG. 1) of the housing 2 can be made as small as possible.
  • the screw shaft 33 is provided with through holes 33b opened at both end surfaces in the axial direction, and a stroke detection sensor 55 for detecting the axial displacement amount of the screw shaft 33 is disposed in the through hole 33b. Yes.
  • the installation space for the stroke detection sensor 55 does not have to be provided separately on the outside in the axial direction of the motor part A, etc., so that the electric actuator 1 is compact in the axial direction and excellent in the operation accuracy of the output shaft. Can be realized.
  • the rotor inner 26 as a hollow rotating shaft is rotatably supported at one end in the axial direction by a rolling bearing 27 disposed in the vicinity of one end in the axial direction of the rotor core 24a, and the other in the axial direction of the rotor core 24a.
  • the other end portion in the axial direction is rotatably supported by a rolling bearing 30 disposed close to the end portion on the side.
  • the rolling bearings 27 and 30 that support the rotor inner 26 may support a radial load about the weight of the rotor 24.
  • the rotor inner 26 integrally including the inner raceway surface 27a of the rolling bearing 27 does not need to be formed of a high-strength material.
  • the rotor inner 26 may be formed of an inexpensive mild steel material in which heat treatment such as quenching and tempering is omitted. Necessary strength can be ensured.
  • the electric actuator 1 of the present embodiment since the rotational motion of the motor 25 is transmitted to the nut member 32 via the planetary gear speed reducer 10, no radial load is generated, and the linear motion of the screw shaft 33 is not caused.
  • the accompanying reaction force (thrust load) is directly supported by the needle roller bearing 47 disposed adjacent to the other axial side of the nut member 32. Accordingly, since the rolling bearing 27 only needs to have a radial positioning function, the rotor inner 26 integrally including the inner raceway surface 27a of the rolling bearing 27 is sufficient for the material specifications as described above. Thereby, the cost of the electric actuator 1 can be reduced.
  • the thrust load acting on the nut member 32 is directly supported by the needle roller bearing 47, the ball screw device 31 (motion converting mechanism portion B) and further the motor portion A are supported. It is possible to effectively suppress the moment load from acting on the rotor 24.
  • the needle roller bearing 47 is disposed within the axial range between the rolling bearings 27 and 30 as in this embodiment, the effect of suppressing the moment load can be enhanced. If the moment load can be suppressed in this way, the operation accuracy and durability of the output member of the electric actuator 1 can be increased, and a small needle roller bearing 47 can be used.
  • the needle roller bearing 47 is disposed near the center in the axial direction between the rolling bearings 27 and 30, and in this case, the effect of suppressing the moment load can be further enhanced. . For this reason, the miniaturization of the needle roller bearing 47 can be further promoted. As a result, extremely small ones can be employed as the needle roller bearing 47, the thrust receiving ring 46, and the like, so that the electric actuator 1 can be prevented from being elongated in the axial direction as much as possible.
  • terminal body 50 terminal portion D
  • the terminal body 50 terminal portion D
  • the assemblability is good.
  • two electric actuators 1 (motor part A, motion conversion mechanism part B) are provided by the sandwich structure described above and a structure in which the lead wire of the power feeding circuit and the signal line of the sensor can be pulled out to the outer diameter side of the housing 2.
  • the electric actuator that can operate the two operation objects individually can be realized while having a compact configuration as a whole. Such an electric actuator will be described in detail later).
  • the planetary gear carrier 43 and the nut member 32 which are output members of the planetary gear speed reducer 10 are formed as separate structures, for example, even when the ball screw device 31 having different specifications is employed, the motor unit A (the motor 25 ) And the planetary gear reducer 10 can be shared. As a result, the versatility is improved, and it is also easy to realize a series of electric actuators 1 with a wide variety of developments that share parts.
  • FIGS. 12 is a longitudinal sectional view of an electric actuator according to another embodiment of the present invention
  • FIG. 13 is an enlarged sectional view taken along line JJ in FIG.
  • the following description will focus on the configuration different from the electric actuator 1 shown in FIG. 1 and the like, and the configuration (members / parts) common to the electric actuator 1 shown in FIG. Are denoted by common reference numerals, and redundant description is omitted as much as possible.
  • the electric actuator 100 shown in FIG. 12 includes first and second actuator units 101 and 102 each having a motor part A, a motion conversion mechanism part B, and a terminal part D arranged in a line in the axial direction.
  • the housing 2 of the actuator 100 includes a cylindrical casing 20 disposed at one end portion in the axial direction, a cover 29 disposed at the other end portion in the axial direction, and between the casing 20 and the cover 29.
  • the intermediate casing 80 is disposed, and a combination of the casing 20 and the intermediate casing 80 and the terminal body 50 disposed between the intermediate casing 80 and the cover 29 are included.
  • the terminal body 50 (terminal part D) on the right side in the figure collectively holds electrical components including a power supply circuit for supplying driving power to the motor 25 of the first actuator unit 101.
  • the terminal main body 50 (terminal portion D) collectively holds electrical components including a power feeding circuit for supplying driving power to the motor 25 of the second actuator unit 102.
  • the output member includes a screw shaft 33 formed in a hollow shape, and a hollow inner member 36 ⁇ / b> A (circular solid portion 36 a) accommodated in the inner periphery of the screw shaft 33. And an actuator head 39 ⁇ / b> A as an operation portion C that has an axial through hole and is attached to one end of the screw shaft 33 on one axial direction side.
  • the output member has a screw shaft 33A formed in a hollow shape, a large diameter portion 91a, a small diameter portion 91b, and a flange portion 91d, and the large diameter portion 91a is a screw shaft.
  • a shaft member 91 with a flange as the operation portion C fitted and fixed to the inner periphery of 33A, and a lid member 93 fixed to the end portion on the other axial side of the screw shaft 33A.
  • the small-diameter portion 91b of the shaft member 91 with the flange is disposed on the inner periphery of the inner member 36A and the actuator head 39A constituting the output shaft of the first actuator unit 101, and as shown in FIG. It has a long hole-like through hole 91c opened at two locations spaced apart in the circumferential direction.
  • a pin 37 is inserted into the through hole 91c of the flanged shaft member 91 so as to penetrate the screw shaft 33 and the inner member 36A of the first actuator unit 101 in the radial direction.
  • Guide collars 38 are rotatably fitted on both ends of the pin 37, and the guide collars 38 are fitted in axial guide grooves 20 b provided on the inner peripheral surface of the casing 20.
  • the output member of the first actuator unit 101 and the output member of the second actuator unit 102 can be individually linearly moved.
  • the operation target can be individually operated.
  • the electric actuator 100 is compact as a whole because the two actuator units 101 and 102 are arranged in the axial direction. Therefore, for example, when the electric actuator 100 is mounted on the DCT, a lightweight and compact transmission can be realized.
  • the nut member 32 is rotatably fitted to the outer periphery of the screw shaft 33 via the plurality of balls 34 (the ball screw device 31 is adopted as the motion conversion mechanism portion B).
  • the present invention can also be applied to an electric actuator in which a screw device in which the ball 34 and the top 35 are omitted is used for the motion conversion mechanism portion B.
  • a rolling bearing other than the needle roller bearing 47 for example, a cylindrical roller bearing may be employed.
  • the needle roller bearing 47 is preferable in consideration of the thrust load supporting ability and the axial dimension of the bearing.
  • the compression coil spring 48 that constantly urges the screw shaft 33 toward the origin is provided.
  • the compression coil spring 48 may be used depending on the application that requires the function of urging. It may be omitted if it is not necessary.
  • the planetary gear speed reducer 10 is adopted as the speed reducer.
  • the present invention is also applicable to an electric actuator in which another speed reducer such as a spur gear speed reducer is adopted. can do.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Power Engineering (AREA)
  • Transmission Devices (AREA)
  • Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
  • Rolling Contact Bearings (AREA)

Abstract

L'invention concerne un actionneur électrique (1), lequel actionneur comporte un moteur (A) et un mécanisme de conversion de mouvement (B), le mécanisme de conversion de mouvement (B) comportant un réducteur à engrenages planétaires (10) à titre de réducteur de vitesse pour réduire la vitesse de rotation d'un rotor (24) du moteur (A) et délivrer en sortie ladite rotation, un arbre fileté (33) disposé de façon coaxiale au centre de rotation du rotor (24), et un élément d'écrou (32) monté en rotation sur la périphérie externe de l'arbre fileté (33), et l'arbre fileté (33) se déplaçant de façon linéaire dans la direction axiale avec la rotation de l'élément d'écrou (32). Le rotor (24) comporte un élément interne de rotor (26) comportant l'élément d'écrou (32), qui est couplé à un élément de sortie du réducteur à engrenages planétaires (10) de manière à permettre une transmission de couple, disposé dans sa périphérie interne. L'arbre fileté (33) est formé selon une forme creuse ayant un trou traversant (33b) qui s'ouvre aux deux faces d'extrémité de l'arbre dans la direction axiale.
PCT/JP2017/011060 2016-03-30 2017-03-17 Actionneur électrique WO2017169935A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2016-069027 2016-03-30
JP2016069027A JP2017180674A (ja) 2016-03-30 2016-03-30 電動アクチュエータ

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WO2017169935A1 true WO2017169935A1 (fr) 2017-10-05

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CN114301225B (zh) * 2021-11-22 2023-07-07 广东培敏智能科技有限公司 一种低噪音承载强的新型行星滚柱丝杆装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6131757A (ja) * 1984-07-23 1986-02-14 Masanobu Fukuzumi 直動形駆動装置
JPS62114202U (fr) * 1986-01-10 1987-07-21
JP2003247576A (ja) * 2002-02-22 2003-09-05 Nissin Kogyo Co Ltd 電気式ディスクブレーキの配置構造
JP2005170064A (ja) * 2003-12-05 2005-06-30 Toyota Motor Corp 車輌用操舵装置
JP2015149799A (ja) * 2014-02-05 2015-08-20 トヨタ紡織株式会社 中空モータ

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6131757A (ja) * 1984-07-23 1986-02-14 Masanobu Fukuzumi 直動形駆動装置
JPS62114202U (fr) * 1986-01-10 1987-07-21
JP2003247576A (ja) * 2002-02-22 2003-09-05 Nissin Kogyo Co Ltd 電気式ディスクブレーキの配置構造
JP2005170064A (ja) * 2003-12-05 2005-06-30 Toyota Motor Corp 車輌用操舵装置
JP2015149799A (ja) * 2014-02-05 2015-08-20 トヨタ紡織株式会社 中空モータ

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