JP2020041593A - Electric direct-acting actuator and electric brake device - Google Patents

Abstract

To prevent an excessive load from acting on a structure member, when a direct-acting member is strongly pushed in an axial direction of a structure member of an electric direct-acting actuator.SOLUTION: An electric direct-acting actuator 14 is equipped with a direct-action converting mechanism 24 which converts rotary motion of a rotating member 25 rotatable around an axis and immovable in an axial direction by electric motor 15, into linear motion of a direct-acting member 26 not rotatable around the axis and movable in the axial direction. The rotating member 25 and the direct-acting member 26 are respectively provided with regulating means 42 and 43, and both regulating means 42 and 43 abut on each other in a circumferential direction of the rotations, thereby regulating the linear motion of the direct-acting member 26.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric linear actuator and an electric brake device using the electric linear actuator.

  An example of an electric linear actuator provided with a linear motion conversion mechanism that converts the rotational motion of a rotating member that rotates around an axis by an electric motor into a linear motion in the axial direction of a linear member is disclosed in Patent Document 1, for example. .

  This electric linear motion actuator is employed in, for example, an electric brake device. This electric brake device converts a rotational motion of the electric motor in one direction of a motor shaft into a linear motion of one of axial directions of an outer ring as a direct-acting member (hereinafter, this one is referred to as front), A pressing member provided on the outer ring presses a brake pad against a disk rotor that rotates integrally with a wheel to obtain a braking force. On the other hand, the braking force is released by reversing the rotation direction of the motor shaft of the electric motor and moving the outer ring to the other side in the axial direction (hereinafter, the other side is referred to as the rear side).

  When the outer ring moves backward, a position where the outer ring comes into contact with a retaining ring for fixing the load sensor for detecting the braking force is defined as a retreating end of the outer ring. When the outer ring contacts the retaining ring in the axial direction, and when it is detected that the load on the electric motor has increased due to the contact, control for stopping driving of the electric motor is performed.

JP-A-2016-98873

  In the above-described control of the electric motor at the retreat end of the outer ring, the outer ring continues to move rearward in the axial direction due to inertia even if the drive of the electric motor is stopped with an increase in the load on the electric motor. For this reason, the outer ring is strongly pushed into the retaining ring by the amount of movement due to inertia, and an excessive load may be applied to components such as the retaining ring. Then, biting may occur between the outer ring and the constituent members, and when the outer ring is moved forward again, the smoothness of switching the moving direction may be impaired.

  Therefore, an object of the present invention is to prevent a linear motion member from being strongly pushed in the axial direction of a component of an electric linear motion actuator, thereby preventing an excessive load from acting on this component.

  In order to solve this problem, in the present invention, the rotational movement of the rotating member, which is rotatable around the axis and immovable in the axial direction by the electric motor, is made non-rotatable about the axis and movable in the axial direction. In an electric linear motion actuator provided with a linear motion conversion mechanism that converts the linear motion of the linear motion member into linear motion, a regulating means is provided for each of the rotating member and the linear motion member. An electric linear motion actuator is characterized in that the linear motion of the linear motion member is regulated by abutting each other in the circumferential direction.

  With this configuration, when the regulating means provided on each of the rotating member and the linear motion member abut against each other in the circumferential direction and the electric motor stops driving, the axial force acting on the linear motion member by the abutting force. Inertia force can be suppressed. For this reason, the linear motion in the axial direction of the linear member after the contact of the two restricting means can be reliably restricted, and the linear member is strongly pushed in the axial direction of the components of the electric linear actuator. This can prevent an excessive load from acting on this component.

  In the above configuration, it is preferable that the linear motion is restricted near an end of the linear motion member within a movable range.

  By doing so, the linear motion member moves beyond its movable range due to inertia, so that the linear motion member firmly prevents the problem that the linear motion member strongly contacts the component member and an excessive load acts or bites. can do.

  In each of the above configurations, the linear motion conversion mechanism is capable of rotating and revolving the sun roller to which the rotation of the electric motor is input, a plurality of planetary rollers that are in rolling contact with the outer periphery of the sun roller, and the plurality of planetary rollers. , An outer ring disposed to surround the plurality of planetary rollers, and circumferential links having different lead angles formed on an outer peripheral surface of the planetary roller and an inner peripheral surface of the outer ring, respectively. And a planetary roller screw mechanism that converts the rotation of the planetary roller into a linear movement in the axial direction of the outer ring by engaging the circumferential engagement portions with each other. , The sun roller, the carrier, or a member that rotates around a rotation axis together with the sun roller, the linear motion member is the outer ring, or the shaft with the outer ring. Preferably a structure which is a member for linear movement in the direction.

  With this configuration, the rotational motion of the sun roller or the like corresponding to the rotating member rotating around the axis can be efficiently converted to the linear motion of the outer ring or the like corresponding to the axially movable linear member.

  In each of the above configurations, the regulating unit continuously changes the size of the diameter of the rotating member or the linear member along the circumferential direction, and the change in the size of the diameter becomes discontinuous. Preferably, the projection is formed as a projection formed in the axial direction of the rotating member or the linear moving member.

  By doing so, the rotational movement of the rotating member can be stopped quickly by the contact of the steps or the protrusions in the circumferential direction, and the linear movement of the linear moving member can be restricted.

  The electric linear motion actuator according to each of the above-described configurations includes a brake disk that rotates integrally with a wheel, a pair of brake pads that are axially opposed to each other with the brake disk therebetween, and linearly drives the brake pad in the axial direction. And the electric linear actuator.

  With this configuration, the braking force can be generated by smoothly moving the brake pad in the axial direction based on the operation of the driver by the action of the electric linear motion actuator, and the braking force can be released. Since it is possible to prevent a problem related to the internal mechanism of the electric linear motion actuator, it is possible to ensure high stability of the electric brake device.

  In the electric linear motion actuator according to the present invention, the regulating member is formed on each of the rotating member and the linear moving member constituting the linear motion conversion mechanism, and the regulating members are brought into contact with each other in the circumferential direction of the rotation of the rotating member. Therefore, the linear movement of the linear member in the axial direction is quickly restricted. Therefore, it is possible to reliably prevent the linear motion member from being strongly pushed in the axial direction of the component member of the electric linear motion actuator and applying an excessive load to this component member.

Sectional view of the electric brake device according to the present invention Side view of the electric brake device shown in FIG. FIG. 2 is a sectional view of an electric linear actuator used in the electric brake device of FIG. 1. FIG. 3 is a sectional view of a linear motion conversion mechanism employed in the electric linear motion actuator shown in FIG. 3; 5A and 5B are cross-sectional views illustrating a main part of FIG. 4, wherein FIG. 4A is a front end of an outer ring, and FIG. Sectional view along line VI-VI in FIG. Sectional view along line VII-VII in FIG. Sectional view showing the main part of FIG. Sectional drawing which shows operation | movement of the linear motion conversion mechanism shown in FIG. Sectional drawing of the principal part which shows the 1st modification of the linear motion conversion mechanism shown in FIG. Sectional view along line XI-XI in FIG. Sectional drawing of the principal part which shows the 2nd modification of the linear motion conversion mechanism shown in FIG. Sectional view along the line XIII-XIII in FIG. Sectional drawing of the principal part which shows the modification of the linear motion conversion mechanism shown in FIG. Sectional drawing which shows the 3rd modification of the linear motion conversion mechanism shown in FIG. Sectional view along the XVI-XVI line in FIG. Sectional drawing of the principal part which shows the 4th modification of the linear motion conversion mechanism shown in FIG. Sectional view along line XVIII-XVIII in FIG. Sectional view along line XIX-XIX in FIG.

  An embodiment of an electric brake device 10 and an electric linear motion actuator 14 according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the electric brake device 10 includes a brake disc 11 that rotates integrally with a wheel (not shown), and a pair of brake pads 12 and 13 that face each other in the axial direction with the brake disc 11 interposed therebetween. An electric linear actuator 14 for linearly driving the brake pad 13 in the axial direction is used as a main component, and the brake pads 12 and 13 are pressed against the brake disc 11 by power transmitted from an electric motor 15 (see FIG. 3). To generate a braking force. In the following, the direction of the brake pads 12 and 13 (left direction in FIG. 1) as viewed from the electric linear actuator 14 in the axial direction is referred to as front, and the direction opposite thereto (right direction in FIG. 1) is referred to as rear.

  The electric brake device 10 has a caliper body 19 in which a pair of opposed portions 16 and 17 facing in the axial direction with the brake disc 11 interposed therebetween are connected by a bridge 18 located on the outer diameter side of the brake disc 11. The brake pads 12 and 13 are provided between the opposing portion 16 of the caliper body 19 and the brake disc 11 and between the other opposing portion 17 and the brake disc 11 via the back plates 20 and 21, respectively. Have been. Each of the brake pads 12 and 13 is guided in the axial direction of the brake disc 11 by a pad pin (not shown) attached to the caliper body 19 and a slide portion (not shown) provided on the caliper bracket 22.

  As shown in FIG. 2, the caliper body 19 is supported by a slide pin 23 attached to a caliper bracket 22 fixed to a knuckle (not shown) for supporting wheels so as to be movable in the axial direction of the brake disc 11. I have. Thus, when the brake pad 13 moves forward in the axial direction and is pressed against the brake disk 11, the caliper body 19 moves rearward in the axial direction due to the reaction force received from the brake disk 11, and the movement of the caliper body 19 Thereby, the brake pad 12 on the opposite side is also pressed against the brake disc 11.

  As shown in FIGS. 1, 3 and the like, one opposing portion 17 of the caliper body 19 has a cylindrical caliper housing 17A having both front and rear ends opened in the axial direction, and a radial inner end of the caliper housing 17A. And a caliper flange 17B provided in the direction.

  A translation mechanism 24 is incorporated in the caliper housing 17A. The linear motion conversion mechanism 24 converts the rotational motion of the rotary member 25, which is rotatable around the axis and is immovable in the axial direction by the electric motor 15, to the linear motion member 26, which is non-rotatable about the axis and movable in the axial direction. It has the function of converting to linear motion.

  As shown in FIGS. 4, 6, etc., the linear motion conversion mechanism 24 is disposed at equal intervals in the circumferential direction with a round bar-shaped sun roller 27 to which the rotation of the electric motor 15 is input, and in rolling contact with the outer periphery of the sun roller 27. A plurality of planetary rollers 28, a carrier 29 that holds the plurality of planetary rollers 28 so as to be able to rotate and revolve, a cylindrical outer ring 30 that is arranged so as to surround the plurality of planetary rollers 28 inside, Circumferential engagement portions 31 and 32 having different lead angles are formed on the outer peripheral surface of the planetary roller 28 and the inner peripheral surface of the outer ring 30, and the peripheral portions formed on the planetary roller 28 and the outer ring 30 are different from each other. This is a planetary roller screw mechanism that converts rotation about the axis of the rotating member 25 into linear movement in the axial direction of the translation member 26 by engagement between the direction engaging portions 31 and 32.

  As shown in FIG. 3, a reduction mechanism 33 is accommodated in a cover 34A and a flange 34B provided so as to cover an axially rear end opening of the caliper housing 17A, and the electric motor 15 is accommodated in the flange 34B. Installed. The reduction mechanism 33 transmits the rotation of the motor shaft 15A of the electric motor 15 to the sun roller 27 at a reduced speed.

  As shown in FIG. 2, the reduction mechanism 33 includes a first gear 33A that rotates around an axis integrally with the rotor shaft 15A of the electric motor 15, a second gear 33B that meshes with the first gear 33A, and a second gear 33B. A third gear 33 </ b> C that rotates together with the meshing sun roller 27. The rotation of the electric motor 15 is transmitted to the sun roller 27 while being sequentially decelerated through the plurality of gears 33A, 33B, and 33C.

  A circumferential engaging portion 31 formed on the outer peripheral surface of the planetary roller 28 has a plurality of circumferential grooves extending along the circumferential direction of the planetary roller 28 (hereinafter, denoted by the same reference numerals as the circumferential engaging portion 31). ). A circumferential engaging portion 32 formed on the inner circumferential surface of the outer ring 30 engages with a circumferential groove 31 formed on the planetary roller 28 and extending obliquely with respect to the circumferential direction of the outer ring 30. (Hereinafter, the same reference numeral as that of the circumferential engaging portion 32 is attached). That is, the lead angles of the circumferential groove 31 and the spiral ridge 32 are different from each other, and when the planetary roller 28 rotates in a state where both are engaged, the outer ring 30 moves relative to the planetary roller 28 in the axial direction. In this embodiment, a circumferential groove 31 having a lead angle of 0 degrees is provided on the outer periphery of the planetary roller 28, but a spiral groove having a lead angle different from that of the spiral ridge 32 may be used instead of the circumferential groove 31.

  As shown in FIG. 4 and the like, an insertion hole is formed in the axis of the planetary roller 28, and the roller shaft 35 is inserted through the insertion hole. With this roller shaft 35, the planetary roller 28 rotates around its axis. On the inner surface of the insertion hole, a slide bearing 36 is provided to be interposed between the insertion hole and the roller shaft 35. The planetary roller 28 smoothly rotates around the roller shaft 35 by the slide bearing 36.

  Elastic rings 37 are wound around both end portions of each roller shaft 35 so as to circumscribe the roller shafts 35 of all the planetary rollers 28 arranged at intervals in the circumferential direction. With this configuration, the respective planetary rollers 28 are pressed against the outer periphery of the sun roller 27 by the elastic ring 37, so that slippage between the planetary roller 28 and the sun roller 27 can be prevented.

  The carrier 29 includes a front carrier plate 29A that holds the planetary roller 28 from the front in the axial direction, a rear carrier plate 29B that holds the planetary roller 28 from the rear in the axial direction, and a plurality of connecting rods that connect the two carrier plates 29A and 29B. 29C. Each of the carrier plates 29A and 29B has a disk-like outer shape, and a slide bearing 38 is provided between each of the carrier plates 29A and 29B and the sun roller 27. In addition, a retaining ring 39 that regulates the forward movement of the carrier 29 in the axial direction is provided in front of the front carrier plate 29A in the axial direction.

  As shown in FIG. 7, both carrier plates 29A and 29B are formed with a through hole through which the sun roller 27 is inserted in the center thereof and a plurality of elongated holes extending in the radial direction. The roller shaft 35 is held by the elongated hole so as to be movable in the radial direction of the sun roller 27. The carrier 29 rotates around the axis of the sun roller 27 as the planetary roller 28 revolves.

  As shown in FIG. 4 and the like, a thrust bearing 40 is provided between the rear end of the planetary roller 28 in the axial direction and the rear carrier plate 29B. The thrust bearing 40 allows the planetary roller 28 to smoothly rotate around the roller shaft 35.

  A pressing member 41 is provided at an axially forward opening end of the outer ring 30. The pressing member 41 has a disc-shaped disc portion 41A and an annular flange portion 41B that stands up from the outer peripheral edge of the disc portion 41A in the axial direction, and has a small diameter formed at the tip of the flange portion 41B. The outer periphery of the part is fitted into the inner periphery of the outer ring 30.

  In this embodiment, the front carrier plate 29 </ b> A constituting the carrier 29 is rotated by the rotation of the electric motor 15 around the axis. The linear motion member 26 linearly moves in the axial direction together with 30.

  As shown in FIG. 7, the outer diameter of the outer peripheral edge of the front carrier plate 29A is continuously increased in the clockwise direction in the circumferential direction. A step as the means 42 (hereinafter, the same reference numeral as that of the regulating means 42 is provided) is formed. Further, the inner diameter of the inner peripheral edge of the flange portion 41B of the pressing member 41 is continuously increased in the clockwise direction in the circumferential direction. A step (hereinafter, denoted by the same reference numeral as the restricting means 43) is formed. The steps 42 and 43 formed on the front carrier plate 29A and the pressing member 41, respectively, come into contact with each other in the circumferential direction, thereby rotating around the axis of the front carrier plate 29A and moving the pressing member 41 in the axial direction. Has a regulating effect.

  A spacer 44 is provided axially rearward of the rear carrier plate 29B. The spacer 44 rotates around the axis of the sun roller 27 integrally with the rear carrier plate 29B.

  A load sensor 46 is provided axially rearward of the spacer 44 via a thrust bearing 45. The load sensor 46 applies a reaction force acting on the outer ring 30 from the brake pad 13 during braking via the planetary roller 28, the thrust bearing 40, the rear carrier plate 29B, the spacer 44, and the thrust bearing 45. It has a function of detecting the braking force by transmitting the braking force to the caliper body 19 via the caliper flange 17B. A bearing 47 is provided between the load sensor 46 and the sun roller 27, and both are rotatable relative to each other. A retaining ring 48 is provided at the front end in the axial direction of the load sensor 46, and the retaining ring 48 positions the load sensor 46 so as not to move forward in the axial direction.

  A peripheral groove 49 is formed at the end of the portion where the pressing member 41 is fitted into the outer ring 30. The small-diameter end of the boot 50 is fitted into the peripheral groove 49, and the large-diameter end of the boot 50 is fitted into the peripheral groove 51 formed on the inner periphery of the caliper housing 17A. In this manner, the internal mechanism and the outside of the electric linear motion actuator 14 are separated by the boot 50, and it is ensured that foreign matter such as muddy water enters between the sliding surface between the outer surface of the outer ring 30 and the inner surface of the caliper housing 17A. Can be prevented.

  As shown in FIG. 1, a detent groove 41C is formed on the front surface of the pressing member 41 in the axial direction. On the rear surface in the axial direction of the back plate 21, a detent protrusion 21A is formed to engage with the groove end of the detent groove 41C. The pressing member 41 (outer ring 30) is prevented from rotating with respect to the caliper housing 17A by engaging the rotation preventing projection 21A with the groove end of the rotation preventing groove 41C.

  The operation of the electric linear motion actuator 14 will be described.

  When the electric motor 15 is driven to rotate the sun roller 27 in one direction around the axis, the planetary roller 28 revolves while rotating. At this time, the outer ring 30 and the planetary roller 28 move relative to each other in the axial direction due to the difference in the lead angle between the spiral ridge 32 and the circumferential groove 31, but the planetary roller 28 is moved by the load sensor 46 and the retaining ring 39 together with the carrier 29. Since the movement in the axial direction is restricted, the planetary roller 28 does not move in the axial direction, and the outer ring 30 and the pressing member 41 move forward in the axial direction as shown in FIG. Accordingly, the brake pad 13 pressed forward in the axial direction by the pressing member 41 is pressed against the brake disc 11 to exert a braking force.

  On the other hand, when the sun roller 27 is rotated in the opposite direction around the axis, the outer ring 30 is moved rearward in the axial direction by the reverse operation as shown in FIGS. 4, 5A, 7 and 8. The step 42 formed on the front carrier plate 29A that rotates around the axis of the sun roller 27 and the step 43 formed on the pressing member 41 that moves linearly in the axial direction are separated from each other in the circumferential direction of the rotation of the front carrier plate 29A. Abut With this abutment, the rotational movement of the front carrier plate 29A stops, and the linear movement of the outer ring 30 moving rearward in the axial direction together with the pressing member 41 is restricted.

  The linear movement of the pressing member 41 and the outer ring 30 is regulated at a desired position in the axial direction in accordance with the circumferential position and the axial position of the steps 42 and 43 formed on the front carrier plate 29A and the pressing member 41. However, it is preferable to determine the circumferential position and the axial position of the steps 42 and 43 so that the linear movement is restricted near the rear end of the outer ring 30 within its movable range. In this way, as shown in FIG. 5B, when the outer ring 30 moves to the rear end of the movable range in the axial direction, the components of the outer ring 30 and the electric linear motion actuator 14 (here, the components). The gap g can be secured between the retaining ring and the retaining ring 48), and the occurrence of a trouble due to the contact between the two can be reliably prevented.

  In this embodiment, the diameter of the outer peripheral edge of the front carrier plate 29A or the inner peripheral edge of the flange portion 41B of the pressing member 41 is continuously changed in the circumferential direction, and steps 42 and 43 are formed at the discontinuous points. Therefore, as shown in FIG. 7, the steps 42 and 43 are reinforced from the rear side in the circumferential direction by the large-diameter portion of the outer diameter of the front carrier plate 29A or the small-diameter portion of the inner diameter of the pressing member 41. . For this reason, even if a large impact is applied when the steps 42 and 43 abut, the steps 42 and 43 can be prevented from being damaged by the impact.

  The amount of axial movement of the outer ring 30 when the carrier 29 makes one rotation around the sun roller 27 is smaller than the amount of axial movement of the outer ring 30 when the sun roller 27 makes one rotation around its axis. (That is, the reduction ratio is small). For this reason, as shown in FIG. 5A, the axial direction between the step 42 formed on the front carrier plate 29 </ b> A and the step 43 formed on the pressing member 41 that moves in the axial direction together with the outer ring 30. A large allowance w can be taken, the rotation preventing function can be surely exerted, and the steps 42 and 43 can be prevented from being chipped.

  FIGS. 10 and 11 show a first modification (main part) of the linear motion conversion mechanism 24. The basic configuration of the linear motion converting mechanism 24 is the same as that shown in FIG. 4, but the step 42 is formed on the front carrier plate 29 </ b> A which is the rotating member 25, while the pressing member which is the linear The only difference is that a protrusion (hereinafter, denoted by the same reference numeral as the restricting means 43) is formed on the flange portion 41B of 41 in the axial direction rearward, and the step 42 and the protrusion 43 are engaged in the circumferential direction. ing.

  When the regulating means 43 is formed as a step, the amount of grinding in the circumferential direction is increased, and the processing cost for forming the step is likely to be increased. Since it suffices to fix the fixing member 43 to the flange portion 41B of the pressing member 41 by welding or the like, there is a possibility that the processing cost of the pressing member 41 for forming the restricting member 43 can be reduced.

  FIGS. 12 and 13 show a second modification (main part) of the linear motion conversion mechanism 24. Although the basic configuration of the linear motion conversion mechanism 24 is the same as that shown in FIG. 4, a projection (hereinafter, referred to as an axially forward end) at the outermost diameter portion at the axial front end of the sun roller 27 as the rotating member 25. , The same reference numerals as those of the restricting means 42), and a protrusion (hereinafter, the same reference numeral as the restricting means 43) protruding rearward in the axial direction of the disk portion 41 </ b> A of the pressing member 41, which is the linear motion member 26. The only difference is that the projections 42 and 43 are engaged in the circumferential direction.

  As described in the first modification, the processing cost of the sun roller 27 and the pressing member 41 for forming the regulating units 42 and 43 can be suppressed by forming the regulating units 42 and 43 as the projections 42 and 43, respectively. there is a possibility. Further, as shown in FIG. 14, the number of components can be reduced by integrating the outer ring 30 and the pressing member 41, so that the assembly of the linear motion conversion mechanism 24 can be performed smoothly.

  FIGS. 15 and 16 show a third modification (main part) of the linear motion conversion mechanism 24. Although the basic configuration of the linear motion conversion mechanism 24 is the same as that shown in FIG. 4, a protrusion (hereinafter referred to as a regulating means) protruding forward in the axial direction is formed at the axial front end of the front carrier plate 29A which is the rotating member 25. 42, and the flange 41B of the pressing member 41, which is the linear motion member 26, is provided with a protrusion (hereinafter, the same reference numeral as the regulating means 43) projecting rearward in the axial direction. ) Is formed, and only the two protrusions 42 and 43 are engaged in the circumferential direction.

  As described in the second modification, the processing costs of the front carrier plate 29A and the pressing member 41 for forming the restricting means 42 and 43 are reduced by forming the restricting means 42 and 43 as the projections 42 and 43, respectively. There is a possibility that it can be suppressed.

  FIGS. 17 to 19 show a fourth modification (main part) of the linear motion conversion mechanism 24. FIG. The basic configuration of the linear motion conversion mechanism 24 is the same as that shown in FIG. 4. However, while forming the step 42 in the spacer 44 which is the rotating member 25, the outer ring 30 which is the linear The only difference is that a step 43 is formed at the rear end in the axial direction, and both steps 42 and 43 are engaged in the circumferential direction.

  Also in this case, similarly to the configuration shown in FIG. 4, the rotation of the spacer 44 is stopped, and the linear motion of the outer ring 30 is restricted. It is possible to reliably prevent the occurrence of a problem caused by the contact of the member (here, the retaining ring 48).

  Further, as shown in FIG. 19, four chamfering is performed on the outer periphery of the rear end in the axial direction of the rear carrier plate 29B, and four chamfering is performed on the inner periphery of the spacer 44 to which the rear carrier plate 29B fits. By performing the inner surface processing in which the rear end in the axial direction of the rear carrier plate 29B that is applied fits exactly, relative rotation around the axis between the rear carrier plate 29B and the spacer 44 is disabled. For this reason, by the circumferential abutment of the steps 42 and 43 formed on the outer ring 30 and the spacer 44, the linear movement of the outer ring 30 rearward in the axial direction can be reliably restricted.

  In the electric brake device 10 and the electric linear actuator 14 according to each of the above-described embodiments, the linear member 26 is strongly pushed axially into the component of the electric linear actuator 14, and an excessive load is applied to this component. Is merely an example for solving the problem of the present invention that prevents the function of the present invention. In particular, the shape and position of the regulating members 42 and 43 formed on the rotating member 25 and the linear moving member 26 are such that the regulating members 42 and 43 abut against each other in the circumferential direction, thereby preventing the linear moving member 26 from moving in the axial direction. It can be changed as appropriate as long as it can be regulated.

DESCRIPTION OF SYMBOLS 10 Electric brake device 11 Brake disk 12, 13 Brake pad 14 Electric linear actuator 15 Electric motor 24 Linear conversion mechanism 25 Rotary member 26 Linear member 27 Sun roller 28 Planetary roller 29 Carrier 30 Outer ring 31 Circumferential engagement part ( Circumferential groove)
32 Circumferential engagement part (spiral ridge)
42, 43 regulating means (steps, protrusions)

Claims (5)

The rotational motion of the rotating member (25), which is rotatable around the axis and is not movable in the axial direction by the electric motor (15), is changed to the linear motion member (26), which is not rotatable around the axis and is movable in the axial direction. In an electric linear motion actuator (14) including a linear motion conversion mechanism (24) for converting to linear motion,
Limiting means (42, 43) are provided on each of the rotating member (25) and the translation member (26), and the two limiting means (42, 43) abut on each other in the circumferential direction of the rotation. An electric linear motion actuator, wherein the linear motion of the linear motion member (26) is restricted by the linear motion.   The electric linear motion actuator according to claim 1, wherein the linear motion is restricted near an end of a movable range of the linear motion member (26). The linear motion conversion mechanism (24)
A sun roller (27) to which the rotation of the electric motor (15) is input;
A plurality of planetary rollers (28) that are in rolling contact with the outer periphery of the sun roller (27);
A carrier (29) for holding the plurality of planetary rollers (28) rotatably and revolvably;
An outer ring (30) arranged to surround the plurality of planetary rollers (28);
Circumferential engagement portions (31, 32) formed on the outer peripheral surface of the planetary roller (28) and the inner peripheral surface of the outer ring (30) and having different lead angles from each other;
A planetary roller screw mechanism that converts the rotation of the planetary roller (28) into an axial linear motion of the outer ring (30) by engagement of the circumferential engagement portions (31, 32). So,
The rotating member (25) is the sun roller (27), the carrier (29), or a member that rotates together with the sun roller (27) around a rotation axis, and the linear moving member (26) includes the outer ring (30), 3. The electric linear motion actuator according to claim 1, wherein the linear motion actuator is a member that linearly moves in the axial direction together with the linear motion actuator. 4.   The regulating means (42, 43) continuously changes the diameter of the rotating member (25) or the linear member (26) along the circumferential direction, and the change of the diameter is not changed. A step (42, 43) formed at a continuous portion, or a projection (42, 43) formed so as to protrude in the axial direction of the rotating member (25) or the translation member (26). The electric linear motion actuator according to any one of claims 1 to 3, wherein: A brake disc (11) rotating integrally with the wheels,
A pair of brake pads (12, 13) opposed in the axial direction with the brake disc (11) therebetween;
The electric linear actuator (14) according to any one of claims 1 to 4, which linearly drives the brake pads (12, 13) in the axial direction.
The electric brake device having a.

Images