JP2011179535A - Electromotive linear actuator and electromotive disc brake - Google Patents

Abstract

An object of the present invention is to make it possible to smoothly guide the linear motion of an output member even when a lateral moment acts on the linearly-moving output member, and to insert a spiral ridge into a circumferential groove or a spiral groove. It is to prevent the shoulder of the spiral ridge from contacting the groove edge.
An outer ring member (5) fitted into an inner diameter surface of a cylindrical portion of a housing so as to be slidable in the axial direction is regulated by restricting movement of the carrier (6) supporting the planetary roller (7) in the axial direction. The outer ring member 5 is used as an output member that linearly moves by rotating the outer ring member 5 with a key, and the side wall of the spiral groove 7a on the outer diameter surface of the planetary roller 7 is widened from the groove bottom side to the groove edge side. Tilted.
[Selection] Figure 5

Description

  The present invention relates to an electric linear motion actuator that linearly drives a driven object by converting the rotational motion of an electric motor into linear motion, and an electric brake that presses a brake member against the braked member using the electric linear motion actuator Relates to the device.

  Many of the electric linear actuators that convert the rotational motion of the electric motor into linear motion to drive the driven object linearly employ a ball screw mechanism or a ball ramp mechanism as the motion conversion mechanism. In many cases, a gear reduction mechanism such as a planetary gear reduction mechanism is incorporated so that a large linear driving force can be obtained (see, for example, Patent Document 1).

  The ball screw mechanism and the ball ramp mechanism employed in the electric linear actuator described above have a certain degree of boosting function by a motion conversion mechanism along the lead screw thread and the inclined cam surface. It is not possible to secure a large boosting function that is necessary for the above. For this reason, in the electric linear actuator that employs these motion conversion mechanisms, a separate reduction mechanism such as a planetary gear reduction mechanism is incorporated to increase the driving force. In this way, a separate reduction mechanism is incorporated. Impedes the compact design of the electric linear actuator.

  For such problems, the present inventors can ensure a large boosting function without incorporating a separate speed reduction mechanism, and as an electric linear actuator suitable for an electric brake device that requires a large thrust, A plurality of planetary rollers rotatably supported by the carrier are interposed between a rotating shaft to which rotation is transmitted from the electric motor and an outer ring member fixed to the inner diameter surface of the housing on the outer diameter side of the rotating shaft. The planetary roller revolves while rotating around the rotation shaft as the rotation shaft rotates, and a spiral protrusion is provided on the inner diameter surface of the outer ring member, and the spiral protrusion is provided on the outer diameter surface of the planetary roller. A circumferential groove into which the spiral ridges are fitted at the same pitch as or a spiral groove into which the spiral ridges are fitted at the same pitch as the spiral ridges with different lead angles and revolves while rotating around the rotation axis. Support planetary roller First, a mechanism in which the carrier is relatively moved in the axial direction, the rotational motion of the rotating shaft is converted into the linear motion of the carrier, and the linear drive member connected to the carrier or the carrier is used as the output member for linearly driving the driven object. It has been proposed (see Patent Documents 2 and 3).

  On the other hand, many hydraulic brake devices have been adopted, but in recent years, with the introduction of advanced brake control such as ABS (Antilock Brake System), these controls are performed without a complicated hydraulic circuit. Electric brake devices that can do this are attracting attention. The electric brake device operates an electric motor in response to a brake pedal depression signal or the like, and incorporates an electric linear actuator as described above into a caliper body to press a brake member against a member to be braked (for example, a patent) Reference 4).

JP-A-6-327190 JP 2007-32717 A JP 2007-37305 A JP 2003-343620 A

  Patent Documents 2 and 3 describe an electric linear actuator that uses a linear drive member connected to the carrier or a linear drive member as an output member that linearly moves, and does not incorporate a separate speed reduction mechanism. However, since the linearly moving carrier and the linear drive member have a relatively short length in the axial direction, for example, in an electric brake device using this electric linear actuator, a brake to be driven is used. A tangential force acts on the member from the braked member, but a part of this tangential force acts as a lateral moment on the carrier or linear drive member as an output member connected to the brake member. There is a problem that guidance becomes difficult. When the linear drive member guided by the outer ring member is connected to the brake member, when the brake member is worn, the axial protrusion amount of the linear drive member from the outer ring member is increased, and the guide length is shortened. Therefore, smooth guidance of the linear drive member becomes more difficult.

  Further, in the electric linear actuator described above, the lead angle of the spiral protrusion provided on the inner diameter surface of the outer ring member is different from the lead angle of the circumferential groove or spiral groove provided on the outer diameter surface of the planetary roller. When the outer surface of the roller is in rolling contact with the inner surface of the outer ring member and the spiral protrusion is fitted in the circumferential groove or the spiral groove, the shoulder of the spiral protrusion contacts the groove edge, and this contact resistance is reduced. There is a problem that the conversion efficiency to the linear motion is lowered due to the torcross. Furthermore, the shoulder of the spiral ridge, the circumferential groove, or the groove edge of the spiral groove may be worn or damaged.

  Accordingly, an object of the present invention is to make it possible to smoothly guide the linear movement of the output member even if a lateral moment acts on the linearly moving output member, and to prevent the spiral ridges from forming in the circumferential grooves or spiral grooves. It is to prevent the shoulder of the spiral ridge from coming into contact with the groove edge when fitting.

  In order to solve the above-described problems, the present invention provides a carrier between a rotating shaft to which rotation is transmitted from an electric motor and an outer ring member fitted inside the inner diameter surface of the housing on the outer diameter side of the rotating shaft. A plurality of planetary rollers that are rotatably supported are interposed so that these planetary rollers revolve around the rotation shaft as the rotation shaft rotates, and spirally project on the inner surface of the outer ring member. A circumferential groove into which the spiral ridge is fitted at the same pitch as the spiral ridge, or a spiral ridge with a different lead angle at the same pitch as the spiral ridge, is provided on the outer diameter surface of the planetary roller. The outer ring member and the carrier are moved relative to each other in the axial direction, and the rotational movement of the rotary shaft is converted into the linear movement of the output member in the axial direction to be connected to the linearly moving output member. Electric drive that drives the driven object in a straight line An output member that restricts movement of the carrier in the axial direction, prevents the outer ring member from rotating, and is fitted into the inner diameter surface of the housing so as to be slidable in the axial direction, and linearly moves the outer ring member. As described above, a configuration is adopted in which the circumferential groove or the spiral groove side wall on the outer diameter surface of the planetary roller is inclined so that the groove width extends from the groove bottom side to the groove edge side.

  That is, the movement of the carrier in the axial direction is restricted, the outer ring member is prevented from rotating, the inner ring surface of the housing is slidably fitted in the axial direction, and the outer ring member is used as an output member that linearly moves. The outer ring member as a member can be guided with a long dimension in the axial direction on the inner diameter surface of the housing, and even if a lateral moment acts on the linearly moving output member, the linear motion of the output member can be smoothly guided. By tilting the side wall of the circumferential groove or spiral groove on the outer diameter surface of the planetary roller so that the groove width spreads from the groove bottom side to the groove edge side, the spiral ridges on the inner diameter surface of the outer ring member become circumferential grooves or When fitting into the spiral groove, the shoulder of the spiral protrusion was prevented from contacting the groove edge.

  When the spiral protrusion is fitted into the circumferential groove or the spiral groove by inclining the side surface of the spiral protrusion on the inner diameter surface of the outer ring member so that the width of the spiral narrows from the base side to the top side, It is possible to prevent the shoulder portion from contacting the inclined side wall of the groove.

  By making the inclination angle of the side surface of the spiral ridge equal to the inclination angle of the side wall of the circumferential groove or the spiral groove, the side surface of the spiral ridge fitted into the circumferential groove or the spiral groove is inclined. The spiral ridges can be satisfactorily engaged with the circumferential grooves or the spiral grooves.

  By forming at least one of the side wall of the circumferential groove or the spiral groove and the side surface of the spiral protrusion with a convex curved surface having a middle height in the inclined direction, the spiral protrusion is fitted into the circumferential groove or the spiral groove. Sometimes, the side surfaces of the spiral ridges can be deviated from the base side or the top side so as not to come into contact with the side walls of the grooves.

  By making the convex curved surface an arc surface, the convex curved surface can be easily formed with high accuracy.

  By making the radius of curvature of the arc surface larger than the height of the spiral ridge, the contact area between the side surface of the spiral ridge and the circumferential groove or the side wall of the spiral groove is increased, and these contact surfaces The pressure can be reduced.

  By chamfering at least one of the circumferential groove or the groove edge of the spiral groove and the shoulder of the spiral protrusion, when the spiral protrusion is fitted into the circumferential groove or the spiral groove, It is possible to prevent the shoulder from contacting the groove edge. In addition, when chamfering is performed on the circumferential edge of the circumferential groove or the spiral groove, the contact pressure of the part where the circumferential groove of the planetary roller or the groove edge of the spiral groove is in rolling contact with the inner diameter surface of the outer ring member should be reduced. Can do.

  The chamfer can be formed by only one or a plurality of straight lines or R curves, or can be formed by combining these straight lines and R curves.

  Chamfering can be easily performed by forming the chamfering by barrel polishing.

  The chamfer can also be formed by cutting.

  By forming the spiral ridges provided on the inner diameter surface of the outer ring member with the strip members that surround the spiral grooves provided on the inner diameter surface of the outer ring member, the spiral ridges can be easily and accurately formed.

  By forming the strip member by drawing a metal, it is possible to increase the strength by work hardening using an inexpensive metal material with few alloy components and to form the strip member at a high yield at a low cost. Further, if the strip member is wound in a spiral shape during the drawing process, it is possible to facilitate the circumferential attachment to the spiral groove.

  The present invention also includes an electric linear actuator that linearly drives the brake member by converting the rotational motion of the electric motor into linear motion, and presses the brake member that is linearly driven against the braked member. Therefore, by adopting a configuration in which any one of the above-described electric linear actuators is used as the electric linear actuator, a tangential force acting on the brake member from the braked member is laterally applied to the output member that moves linearly. Even when acting as a moment, the linear movement of the output member can be smoothly guided, and when the spiral protrusion on the inner diameter surface of the outer ring member is fitted into the circumferential groove or the spiral groove, the shoulder of the spiral protrusion is It was made not to touch a groove edge.

  The electric linear actuator of the present invention restricts the movement of the carrier supporting the planetary roller in the axial direction, prevents the outer ring member from rotating, and is fitted into the inner diameter surface of the housing so as to be slidable in the axial direction. Since the member is an output member that linearly moves, and the side wall of the circumferential groove or spiral groove on the outer diameter surface of the planetary roller is inclined so that the groove width extends from the groove bottom side to the groove edge side, the output that linearly moves Even when a lateral moment acts on the member, the linear motion of the output member can be smoothly guided, and when the spiral protrusion on the inner diameter surface of the outer ring member is fitted into the circumferential groove or the spiral groove, By preventing the shoulders of the spiral ridges from coming into contact with the groove edges, the torcross caused by these contact resistances can be eliminated, the conversion efficiency to linear motion can be improved, and the shoulders and circumferential directions of the spiral ridges can be increased. Groove or spiral It is possible to prevent wear and damage of the groove edge portion.

  In the electric brake device of the present invention, the brake member that presses against the member to be braked is linearly driven by using the electric linear actuator described above, so that the tangential force acting on the brake member from the member to be braked is applied. However, even when acting as a lateral moment on the linearly moving output member, the linear motion of the output member can be smoothly guided, and the spiral ridges on the inner diameter surface of the outer ring member are formed in the circumferential grooves or spiral grooves. When fitting, the shoulder of the spiral ridge is not in contact with the edge of the groove, the torcross resulting from these contact resistances can be eliminated, the conversion efficiency into linear motion can be improved, and the spiral ridge It is also possible to prevent wear and damage to the shoulder portions of the sleeves, the circumferential grooves or the groove edges of the spiral grooves.

A longitudinal sectional view showing an embodiment of an electric linear actuator Sectional view along the line II-II in FIG. Sectional view along line III-III in FIG. (A), (b) is a front view which shows the spiral protrusion of the outer ring member of FIG. 1, and the spiral groove of the planetary roller, respectively. Sectional drawing which shows the engagement state of the spiral protrusion of the outer ring member of FIG. 1, and the spiral groove of a planetary roller Sectional drawing which expands and shows the spiral protrusion of the outer ring member of FIG. 5, and the spiral groove of a planetary roller (A)-(d) is sectional drawing which shows the modification of the chamfering of FIG. 6, respectively. (A)-(c) is sectional drawing which shows the modification of the spiral protrusion and spiral groove of FIG. 6, respectively. 1 is a longitudinal sectional view showing an electric brake device employing the electric linear actuator of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 3, the electric linear actuator is provided with a flange 1b projecting to one end of a cylindrical portion 1a of the housing 1, and the electric motor 2 is connected to the cylindrical portion 1a on the flange 1b. Mounted in parallel, the rotation of the rotor shaft 2a of the electric motor 2 is transmitted to the rotating shaft 4 disposed at the center of the cylindrical portion 1a by the gears 3a, 3b, 3c. Four planetary rollers 7 rotatably supported by the carrier 6 are interposed between the outer ring member 5 fitted in the inner diameter surface of the cylindrical portion 1a so as to be slidable in the axial direction, and each planetary roller 7 rotates. As the shaft 4 rotates, it revolves while rotating around it.

  A lid 1c is attached to the side of the housing 1 where the flange 1b is provided, and the gears 3a, 3b, 3c are arranged so as to mesh with each other in the same axial section of the space covered with the lid 1c. The gears 3a, 3b, and 3c may be spur gears or helical gears, and the material may be a resin that can be reduced in weight, or a sintered material that can be easily molded, in addition to a metal such as steel. it can. The gears 3a, 3b, and 3c may be formed of different materials. A shaft support member 8 is fitted on the lid 1c side of the cylindrical portion 1a, and the base end side of the rotating shaft 4 to which the gear 3c is attached is supported by the shaft support member 8 with a ball bearing 9. The shaft support member 8 is fixed to the housing 1 with retaining rings 10 on both sides, and also serves to restrict movement of the rotary shaft 4 and the carrier 6 in the axial direction. An intermediate gear 3b meshed with the gear 3a and the gear 3c attached to the rotor shaft 2a is supported by a ball bearing 12 on a shaft pin 11 passed between the flange 1b and the lid 1c.

  The carrier 6 that revolves together with the planetary roller 7 is externally fitted to the rotary shaft 4 through a slide bearing 13 having a carrier body 6a made of a sintered material so as to be relatively rotatable, and through a thrust roller bearing 14. Abutting on the end face of the shaft support member 8, the movement of the rotating shaft 4 toward the base end side is restricted. The slide bearing 13 may be formed of resin, ceramics, a metal such as an aluminum alloy or a copper alloy, or a composite material thereof. Each planetary roller 7 is rotatably supported on a support pin 6b of the carrier 6 by a needle roller bearing 15, and a holding plate 6c fixed to the support pin 6b with a retaining ring 16 on the opposite side to the carrier body 6a. It is prevented from coming off and its rotation is supported by the carrier body 6 a by a thrust roller bearing 17.

  A retaining ring 18 is mounted on the distal end side of the rotating shaft 4, and a holding plate 6 c of the carrier 6 is brought into contact with the retaining ring 18 via a slide bearing 19 formed of a sintered material, so that the distal end side of the rotating shaft 4. The movement of the carrier 6 is restricted. The slide bearing 19 may also be formed of a resin, ceramics, a metal such as an aluminum alloy or a copper alloy, or a composite material thereof. The holding plate 6c is integrally formed with a partial cylindrical portion 6d extending to the planetary roller 7 side, and a fan-shaped lubricant is applied to the outer diameter surface of the planetary roller 7 on the inner diameter side of the partial cylindrical portion 6d. The member 20 is held. Further, a seal member 21 having a cylindrical peripheral edge portion is fitted into the inner diameter surface of the end portion of the outer ring member 5 so as to block the inner diameter portion where the planetary roller 7 and the lubricant application member 20 are arranged from the outside. ing. The seal member 21 is formed by pressing a thin steel plate. The seal member 21 can also be formed of resin or rubber.

  A driven object is connected to the front end side of the outer ring member 5, and a key 22 is provided on the front end surface of the outer ring member 5 so as not to be rotated by the driven object. Accordingly, the outer ring member 5 fitted in the inner diameter surface of the cylindrical portion 1a of the housing 1 so as to be slidable in the axial direction moves relative to the carrier 6 in which the axial movement in both directions is restricted, and outputs linearly. It becomes a member. The cylindrical portion 1a on the side where the driven object is connected to the outer ring member 5 is open, and the outer ring member 5 is guided in a long length in the axial direction on the inner diameter surface of the cylindrical portion 1a and protrudes from the cylindrical portion 1a. Smooth linear motion with long strokes.

  As shown in FIG. 4 (a), two spiral grooves 5a are provided on the inner diameter surface of the outer ring member 5 to which the planetary rollers 7 are in rolling contact, and separate strip members are attached around the spiral grooves 5a. 5 b, two spiral ridges are formed on the inner diameter surface of the outer ring member 5. The strip member 5b is formed by drawing a low carbon steel, and the strength is increased by work hardening.

  Further, as shown in FIG. 4B, the spiral ridge formed by the strip member 5b is fitted in the outer diameter surface of the planetary roller 7, and the lead angle is different at the same pitch as the spiral ridge. A spiral groove 7a is provided. Due to the engagement of the spiral ridges and the spiral grooves 7a, the planetary roller 7 that revolves while rotating around the rotation shaft 4 has a shaft angle with the outer ring member 5 due to the difference in the lead angle between the spiral ridges and the spiral grooves 7a. Move relative to the direction. The reason why the spiral ridges of the outer ring member 5 are two multi-threads is to increase the degree of freedom in setting the difference in the lead angle with the spiral groove 7a of the planetary roller 7. Articles may be used. The spiral groove 7a of the planetary roller 7 may be a circumferential groove having the same pitch as that of the spiral protrusion.

  As shown in FIG. 5, the outer circumferential surface of the spiral groove 7a formed on the outer circumferential surface of the planetary roller 7 is formed by a strip member 5b with inclined side walls so that the groove width extends from the groove bottom side to the groove edge side. The inner surface of the spiral ridge 5 is inclined at an angle equal to the inclination angle of the side wall of the spiral groove 7a so that the width of the spiral ridge narrows from the base side to the top side. Accordingly, when the planetary roller 7 is in rolling contact with the inner surface of the outer ring member 5 and the spiral ridges of the outer ring member 5 are fitted into the spiral grooves 7a having different lead angles, the shoulders of the spiral ridges are The spiral ridge fitted into the spiral groove 7a does not come into contact with the groove edge of the spiral groove 7a, and is evenly brought into contact with the side wall of the spiral groove 7a whose side surface is inclined. Good engagement with 7a.

  As shown in an enlarged view in FIG. 6, a chamfer 23a formed by a single R curve is applied to the groove edge of the spiral groove 7a. Therefore, when the spiral ridge of the outer ring member 5 is fitted into the spiral groove 7a, the shoulder of the spiral ridge can be prevented from contacting the groove edge, and the groove of the spiral groove 7a of the planetary roller 7 can be prevented. The contact pressure at the portion where the edge portion is in rolling contact with the inner diameter surface of the outer ring member 5 can be reduced. The chamfer 23a is formed by barrel polishing.

  FIGS. 7A to 7D show modifications of the chamfer 23a of the spiral groove 7a shown in FIG. 7A shows the chamfer 23a formed with a single straight line, FIG. 7B shows the chamfer 23a formed with two straight lines, and FIG. 7C shows the chamfer 23a with a radius of curvature. FIG. 7D shows a chamfer 23a formed by combining one straight line and two R curves having a radius of curvature R4. These chamfers 23a are formed by barrel polishing or cutting.

  FIGS. 8A to 8C show modified examples of the spiral protrusion of the outer ring member 5 and the spiral groove 7a of the planetary roller 7 shown in FIG. 8 (a) shows the shoulder of the spiral ridge with chamfering 23b, and FIG. 8 (b) shows that the side surface of the spiral ridge has a middle height in the inclined direction, and the height H of the spiral ridge. FIG. 8 (c) is a modification of FIG. 8 (b), and the side wall of the spiral groove 7a also has a middle height in the inclined direction, and the height of the spiral ridges. It is formed by an arc surface 24a having a radius of curvature R6 larger than H, and the chamfer 23a of the groove edge portion is omitted. 8B and 8C, when the spiral ridges are fitted into the spiral grooves 7a, the side surfaces of the spiral ridges are biased on the base side or the top side, and the side walls of the spiral grooves 7a. It can be made not to abut against.

  FIG. 9 shows an electric brake device that employs the electric linear actuator described above. This electric brake device is a disc brake in which a brake pad 33 as a brake member is disposed oppositely on both sides of a disc rotor 32 as a braked member inside the caliper body 31, and the electric linear actuator is connected to the caliper body 31. The outer ring member 5 as an output member that linearly moves is locked to a brake pad 33 as a driven object by a key 22 so that the brake pad 33 is pressed against the disc rotor 32. In this figure, the electric linear actuator is shown in a cross section orthogonal to the cross section shown in FIG.

  In the embodiment described above, the spiral ridges on the inner diameter surface of the outer ring member are formed by separate strip members fitted into the spiral grooves, but the spiral ridges can also be formed integrally with the outer ring member.

DESCRIPTION OF SYMBOLS 1 Housing 1a Cylindrical part 1b Flange 1c Cover 2 Electric motor 2a Rotor shaft 3a, 3b, 3c Gear 4 Rotating shaft 5 Outer ring member 5a Spiral groove 5b Strip member 6 Carrier 6a Carrier main body 6b Support pin 6c Holding plate 6d Partial cylindrical part 7 Planet Roller 7a Spiral groove 8 Shaft support member 9 Ball bearing 10 Retaining ring 11 Shaft pin 12 Ball bearing 13 Sliding bearing 14 Thrust roller bearing 15 Needle roller bearing 16 Retaining ring 17 Thrust roller bearing 18 Retaining ring 19 Sliding bearing 20 Lubricant application member 21 Seal member 22 Key 23a, 23b Chamfer 24a, 24b Arc surface 31 Caliper body 32 Disc rotor 33 Brake pad

Claims (13)

  A plurality of planetary rollers rotatably supported by the carrier are interposed between a rotating shaft to which rotation is transmitted from the electric motor and an outer ring member fitted into the inner diameter surface of the housing on the outer diameter side of the rotating shaft. These planetary rollers revolve while rotating around the rotation axis as the rotation shaft rotates, and provided with spiral ridges on the inner diameter surface of the outer ring member, on the outer diameter surface of the planetary roller, The outer ring member and the carrier are provided with a circumferential groove into which the spiral ridges are fitted at the same pitch as the spiral ridges, or a spiral groove into which the spiral ridges are fitted at different pitches and the same pitch as the spiral ridges. The motor linearly drives the driven object connected to the linearly moving output member by converting the rotational motion of the rotary shaft into the linear motion of the output member in the axial direction. In the actuator, the carrier As an output member that linearly moves the outer ring member as an output member that restricts the movement of the outer ring member in the axial direction, prevents the outer ring member from rotating, and is fitted inside the inner diameter surface of the housing so as to be able to slide in the axial direction An electric linear actuator characterized in that a side wall of a circumferential groove or a spiral groove on an outer diameter surface is inclined so that a groove width extends from a groove bottom side to a groove edge side.   2. The electric linear actuator according to claim 1, wherein a side surface of the spiral protrusion on the inner diameter surface of the outer ring member is inclined so that the width of the spiral narrows from the base side to the top side.   The electric linear actuator according to claim 2, wherein an inclination angle of a side surface of the spiral ridge is equal to an inclination angle of a side wall of the circumferential groove or the spiral groove.   4. The electric linear actuator according to claim 2, wherein at least one of a side wall of the circumferential groove or the spiral groove and a side surface of the spiral ridge is formed as a convex curved surface having a middle height in the inclined direction.   The electric linear actuator according to claim 4, wherein the convex curved surface is an arc surface.   The electric linear actuator according to claim 5, wherein a radius of curvature of the arc surface is larger than a height of the spiral ridge.   The electric linear actuator according to any one of claims 1 to 6, wherein at least one of a groove edge portion of the circumferential groove or the spiral groove and a shoulder portion of the spiral protrusion is chamfered.   The electric linear actuator according to claim 7, wherein the chamfering is formed by only one or a plurality of straight lines or R curves, or a combination of these straight lines and R curves.   The electric linear actuator according to claim 7 or 8, wherein the chamfer is formed by barrel polishing.   The electric linear actuator according to claim 7 or 8, wherein the chamfer is formed by cutting.   The electric linear actuator according to any one of claims 1 to 10, wherein the spiral protrusion provided on the inner diameter surface of the outer ring member is formed by a strip member that is circumferentially attached to a spiral groove provided on the inner diameter surface of the outer ring member.   The electric linear actuator according to claim 11, wherein the strip member is formed by drawing a metal.   An electric brake device that includes an electric linear actuator that linearly drives a brake member by converting a rotational movement of the electric motor into a linear movement, and presses the brake member that is linearly driven against the member to be braked. An electric brake device using the electric linear actuator according to any one of claims 1 to 12 as a dynamic actuator.

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