WO2023276770A1

WO2023276770A1 - Planetary roller screw type linear motion mechanism and electric brake device

Info

Publication number: WO2023276770A1
Application number: PCT/JP2022/024650
Authority: WO
Inventors: 雅章江口
Original assignee: Ntn株式会社
Priority date: 2021-06-28
Filing date: 2022-06-21
Publication date: 2023-01-05
Also published as: JP2023004701A

Abstract

The width dimension of a second long hole (32) is set to be larger than the width dimension of a first long hole (31). A rotation-inhibition-shape portion (46) and a first partial cylindrical surface (47) are formed on an outer periphery of a first end portion (16) of a roller shaft (15), and t first rotation-inhibition-shape portion (46) engages with a longitudinal surface (45) of the first long hole (31) so as to inhibit the roller shaft (15) from rotating. A second rotation-inhibition-shape portion (49) and a second partial cylindrical surface (50) are formed on an outer periphery of a second end portion (17) of the roller shaft (15), and only the second partial cylindrical surface (50) is brought into contact with and supported by a longitudinal surface (48) of the second long hole (32).

Description

Planetary roller screw type linear motion mechanism and electric brake device

The present invention relates to a planetary roller screw type linear motion mechanism used in an electric linear motion actuator, and an electric brake device using the planetary roller screw type linear motion mechanism.

As a linear motion mechanism that converts rotational motion input from the outside into linear motion and outputs it, for example, a planetary roller screw type linear motion mechanism as disclosed in Patent Document 1 is known.

The planetary roller screw type linear motion mechanism of Patent Document 1 includes a rotating shaft to which rotation is input from the outside, a hollow cylindrical outer ring member surrounding the rotating shaft, and an inner circumference of the outer ring member and an outer circumference of the rotating shaft. A plurality of planetary rollers arranged at intervals in the circumferential direction therebetween, a plurality of roller shafts rotatably supporting the plurality of planetary rollers, and a carrier holding both ends of the plurality of roller shafts. . A helical ridge is provided on the inner circumference of the outer ring member, and a helical groove or a circumferential groove that engages with the helical ridge is provided on the outer circumference of each planetary roller.

The carrier has a first disk and a second disk that face each other in the axial direction with a plurality of planetary rollers interposed therebetween, and a connecting portion that passes between the plurality of planetary rollers and connects the first disk and the second disk. The first disk has a plurality of first elongated holes for radially movably holding the first ends of the roller shafts, and the second disk has a plurality of roller shafts. A plurality of circumferentially spaced second slots are formed to movably retain the second end of the shaft in the radial direction.

Furthermore, a first C-shaped ring spring and a second C-shaped ring spring are stretched over the first end and the second end of the roller shaft, respectively, in a state in which the diameter is elastically expanded and deformed. , the elastic restoring forces of the C-shaped ring springs urge the first end and the second end of each roller shaft radially inward, and as a result, the planetary rollers are pressed against the outer circumference of the rotating shaft. there is

In this planetary roller screw type linear motion mechanism, when rotation is input to the rotating shaft from the outside, the rotation of the rotating shaft is transmitted to the planetary rollers that are in rolling contact with the outer circumference of the rotating shaft. It revolves around its axis of rotation. At this time, the engagement between the spiral groove or the circumferential groove on the outer circumference of the planetary roller and the spiral ridge on the inner circumference of the outer ring member causes the outer ring member, which is prevented from rotating from the outside, to move in the axial direction. Thus, the planetary roller screw type linear motion mechanism converts rotation of the rotating shaft into linear motion of the outer ring member.

Compared to other types of linear motion mechanisms such as feed screw mechanisms, this planetary roller screw type linear motion mechanism is compact and can generate a large axial load. There is an advantage that it is suitable for an electric brake device that is used.

In such a planetary roller screw-type linear motion mechanism, when the planetary roller rotates, the roller shaft supporting the planetary roller rotates together with the planetary roller, possibly causing the roller shaft to rotate. When the roller shaft rotates, the contact portion of the roller shaft with the C-shaped ring spring wears, and the amount of diameter expansion deformation of the C-shaped ring spring decreases according to the wear. The elastic restoring force of the ring spring is insufficient, and as a result, problems such as idling of the rotating shaft may occur.

Therefore, in order to prevent the roller shafts from rotating together, in Patent Document 1, a pair of flat surfaces (hereinafter referred to as "width across flats") are provided on the outer circumference of the first end and the outer circumference of the second end of each roller shaft. ) so that the width across flats of the first end is engaged with the longitudinal surface of the first elongated hole of the first disc, and the width across flats of the second end is also the longitudinal direction of the second elongated hole of the second disc. By engaging the surfaces, the roller shaft is prevented from rotating by the first disk and the second disk.

JP 2016-217420 A

By the way, when the inventor of the present application considered automating the production of the planetary roller screw type linear motion mechanism of Patent Document 1, it was found that it would be difficult to automate the work of assembling the roller shaft of the planetary roller to the carrier. faced a problem.

That is, first, a carrier composed of a first disc, a second disc, and a connecting portion connecting the two discs is assembled, and then the roller shaft is connected to the first long hole of the first disc and the second disc of the second disc. If the roller shaft can be inserted into the two elongated holes, it is possible to automate the assembling work of the roller shaft. can't This is because the width dimension of the first slot and the width dimension of the second slot correspond to the width across flats of the end portion of the roller shaft, and are narrower than the outer diameter dimension of the roller shaft.

Therefore, as a method of making it possible to insert the roller shaft into the first long hole and the second long hole after assembling the carrier, a width across flats is formed only at the first end of the roller shaft, A method is conceivable in which the second end of the roller shaft does not form the width across flats. In this case, the second long hole should not have a dimension corresponding to the width across flats formed at the first end of the roller shaft, but should have a wider width dimension corresponding to the outer diameter dimension of the roller shaft. to form. By doing so, first, the carrier composed of the first disk, the second disk, and the connecting portion connecting the two disks is assembled, and then the roller shaft is connected to the second elongated hole from the second disk side. It is possible to sequentially insert them into the first elongated holes.

However, when adopting the method of forming the width across flats only at the first end of the roller shaft and not forming the width across flats at the second end of the roller shaft as described above, the first end of the roller shaft Since the shape and size of the portion and the shape and size of the second end are different from each other, it becomes necessary to distinguish between the front and rear directions of the roller shaft when inserting the roller shaft into the first long hole and the second long hole. . Therefore, in order to automate the work of assembling the roller shaft to the carrier, first, the shape of the end of the roller shaft is detected, and based on the detected shape of the end of the roller shaft, the correct orientation of the roller shaft (roller shaft The first end of the roller shaft should be the front side of the insertion direction, and the second end of the roller shaft should be the rear side of the insertion direction), but it is costly to provide such facilities.

Therefore, when inserting the roller shaft into the first elongated hole and the second elongated hole, there is no need to distinguish between the front and rear directions of the roller shaft. For example, as shown in FIG. A method of extension is conceivable. That is, as shown in FIG. 25A, the roller shaft is extended to a position where the width across flats 72 of the first end 71 of the roller shaft 70 engages the longitudinal surface 75 of the first elongated hole 74 of the first disc 73 . A possible method is to extend the roller shaft 70 so that the width across flats 77 of the second end 76 of the roller shaft 70 does not reach the position of the second long hole 79 of the second disk 78 when the roller shaft 70 is inserted. . Here, as shown in FIG. 25B, a width across flats 72 is formed at the first end 71 of the roller shaft 70, and as shown in FIG. is formed. Further, as shown in FIG. 25C, the width dimension of the second elongated hole 79 is set not to the dimension corresponding to the width across flats 77 but to the dimension corresponding to the outer diameter dimension of the roller shaft 70 . With this configuration, the shape and dimensions of the first end portion 71 of the roller shaft 70 and the shape and dimensions of the second end portion 76 of the roller shaft 70 are the same, so the roller shaft 70 can be positioned between the second long hole 79 and the first end portion 79 . There is no need to distinguish between the front and rear directions of the roller shafts 70 when they are sequentially inserted into the long holes 74 .

However, when the method of extending the total length of the roller shaft 70 is adopted as shown in FIG. Moreover, the mass of the planetary roller screw type linear motion mechanism is also increased, which is not preferable.

The problem to be solved by the present invention is to provide a planetary roller screw type linear motion mechanism that facilitates automation of the work of assembling the roller shaft of the planetary roller to the carrier.

In order to solve the above problems, the present invention provides a planetary roller screw type linear motion mechanism having the following configuration.
a rotating shaft;
a hollow cylindrical outer ring member surrounding the rotating shaft;
a plurality of planetary rollers arranged at intervals in the circumferential direction between the inner periphery of the outer ring member and the outer periphery of the rotating shaft;
a spiral ridge provided on the inner periphery of the outer ring member;
a spiral groove or a circumferential groove provided on the outer circumference of each planetary roller so as to engage with the spiral ridge;
a plurality of roller shafts that rotatably support the plurality of planetary rollers;
a first disk and a second disk axially opposed to each other with the plurality of planetary rollers interposed therebetween; and a connecting portion passing between the plurality of planetary rollers and connecting the first disk and the second disk. a carrier;
A plurality of first elongated holes are formed in the first disk at intervals in a circumferential direction to hold the first ends of the plurality of roller shafts so as to be movable in a radial direction,
Planetary roller screw type linear motion, wherein a plurality of second elongated holes are formed in the second disk at intervals in the circumferential direction to hold the second ends of the plurality of roller shafts so as to be movable in the radial direction. In the mechanism
The width dimension of the second long hole is wider than the width dimension of the first long hole,
A first anti-rotation shape portion and a first partial cylindrical surface adjacent to the first anti-rotation shape portion around the axis of the roller shaft are formed on the outer circumference of the first end portion of the roller shaft. , the first anti-rotation shaped portion is engaged with the longitudinal surface of the first elongated hole to prevent rotation of the roller shaft,
A second anti-rotation shape portion and a second partial cylindrical surface adjacent to the second anti-rotation shape portion around the axis of the roller shaft are formed on the outer circumference of the second end portion of the roller shaft. , the shape and dimensions of the second end are the same as the shape and dimensions of the first end, but the angular position of the second detent shape about the axis of the roller shaft and the first detent Different from the angular position of the shaped portion about the axis of the roller shaft, only the second partial cylindrical surface out of the second anti-rotation shaped portion and the second partial cylindrical surface is aligned with the longitudinal surface of the second long hole. A planetary roller screw type linear motion mechanism characterized by being supported in contact.

In this way, since the second elongated hole is formed to have a wide width, first the carrier composed of the first disk, the second disk, and the connecting portion connecting the two disks is assembled, and then the roller shaft is assembled. can be inserted into the second long hole and the first long hole in order from the second disk side. Moreover, since the shape and dimensions of the first end of the roller shaft and the shape and dimensions of the second end of the roller shaft are the same, when the roller shaft is inserted into the second elongated hole and the first elongated hole in this order, There is no need to distinguish between the front and rear orientations of the roller shafts. Therefore, it is easy to automate the work of assembling the roller shaft of the planetary roller to the carrier.

It is preferable that the first anti-rotation shape portion and the second anti-rotation shape portion adopt a flat surface having a shape obtained by cutting the outer periphery of the roller shaft along a plane parallel to the axial center of the roller shaft.

With this configuration, since the first detent shape is a flat surface, it comes into surface contact with the longitudinal surface of the first elongated hole, and it is possible to effectively detent the roller shaft so that it does not rotate. Further, the reduction in the cross-sectional area of the first end and the second end of the roller shaft due to the formation of the first anti-rotation shape portion and the second anti-rotation shape portion is minimized, and the first end of the roller shaft is The strength of the portion and the second end can be easily ensured, and the first anti-rotation shape portion and the second anti-rotation shape portion can be processed with high accuracy at a low processing cost.

The difference between the angular position of the first anti-rotation shape portion about the axis of the roller shaft and the angular position of the second anti-rotation shape portion about the axis of the roller shaft is in the range of 40° or more and 140° or less. preferably set to .

With this configuration, the difference between the angular position of the first detent shape portion and the angular position of the second detent shape portion is large. When engaged, it is possible to reliably locate the second partial cylindrical surface at the position of the longitudinal surface of the second elongated hole of the second disc.

a first C-shaped ring spring for biasing the first end of the roller shaft radially inward; and a second C-shaped ring spring for biasing the second end of the roller shaft radially inward. a ring spring;
A first ring groove with which the first C-shaped ring spring engages is formed on the outer periphery of the first end of the roller shaft,
When a second ring groove with which the second C-shaped ring spring engages is formed on the outer circumference of the second end of the roller shaft,
The difference between the angular position of the first anti-rotation shape portion about the axis of the roller shaft and the angular position of the second anti-rotation shape portion about the axis of the roller shaft is 40° or more and 50° or less, or 130°. It is preferable to set the angle between 140° and 140°.

By doing so, it is possible to ensure the engagement allowance of the second C-shaped ring spring with respect to the second ring groove, and to stabilize the engagement between the second C-shaped ring spring and the second ring groove.

The first anti-rotation shaped portion is a pair of flat surfaces formed parallel to each other on the outer circumference of the first end of the roller shaft with the axis of the roller shaft interposed therebetween,
The second anti-rotation shaped portion may be a pair of parallel flat surfaces formed on the outer periphery of the second end portion of the roller shaft with the axis of the roller shaft interposed therebetween.

The first anti-rotation shaped portion is formed only at one location on the outer periphery of the first end of the roller shaft,
A configuration may be adopted in which the second anti-rotation shaped portion is formed only at one location on the outer periphery of the second end portion of the roller shaft.

In addition, the present invention also provides an electric brake device having the following configuration as an electric brake device using the planetary roller screw type linear motion mechanism.
the above-mentioned planetary roller screw type linear motion mechanism;
an electric motor that rotationally drives the rotary shaft of the planetary roller screw type linear motion mechanism;
and a brake pad axially pressed by the outer ring member of the planetary roller screw type linear motion mechanism.

In the planetary roller screw type linear motion mechanism of the present invention, since the second elongated hole is formed with a wide width, the carrier is first formed of the first disc, the second disc, and the connecting portion connecting the two discs. is assembled, and then the roller shafts can be sequentially inserted into the second slot and the first slot from the side of the second disk. Moreover, since the shape and dimensions of the first end of the roller shaft and the shape and dimensions of the second end of the roller shaft are the same, when the roller shaft is inserted into the second elongated hole and the first elongated hole in this order, There is no need to distinguish between the front and rear orientations of the roller shafts. Therefore, it is easy to automate the work of assembling the roller shaft of the planetary roller to the carrier.

1 is a sectional view showing an electric linear motion actuator incorporating a planetary roller screw type linear motion mechanism according to a first embodiment of the present invention; FIG. Enlarged cross-sectional view of the vicinity of the planetary roller screw type linear motion mechanism in FIG. Cross-sectional view along the III-III line in Fig. 2 Cross-sectional view along the IV-IV line in Fig. 2 Enlarged view of the vicinity of the roller shaft in FIG. Cross-sectional view along the VI-VI line in Fig. 2 Enlarged view of the vicinity of the roller shaft in FIG. Cross-sectional view along line VIII-VIII in Fig. 2 Enlarged view of the vicinity of the roller shaft in FIG. FIG. 3 is an enlarged view of the roller shaft shown in FIG. 2; Sectional view along line XI-XI in FIG. Cross-sectional view along line XII-XII in FIG. Sectional view showing an example of an electric brake device using the electric linear motion actuator shown in FIG. Partial cross-sectional view of the electric brake device shown in FIG. 13 as seen from the inner side FIG. 5 is a cross-sectional view of the vicinity of the planetary rollers of the planetary roller screw type linear motion mechanism according to the second embodiment of the present invention; Cross-sectional view along line BB in FIG. 15A Cross-sectional view along CC line of FIG. 15A FIG. 15B is an enlarged view of the roller shaft shown in FIG. 15A; Cross-sectional view along the XVII-XVII line in Fig. 16 Sectional view along line XVIII-XVIII in FIG. FIG. 8 is a cross-sectional view of the vicinity of the planetary rollers of the planetary roller screw type linear motion mechanism according to the third embodiment of the present invention; Cross-sectional view along line BB in FIG. 19A Cross-sectional view along CC line of FIG. 19A FIG. 19B is an enlarged view of the roller shaft shown in FIG. 19A; Cross-sectional view along line XXI-XXI in FIG. Sectional view along line XXII-XXII in FIG. FIG. 11 is a cross-sectional view of the vicinity of the planetary rollers of the planetary roller screw type linear motion mechanism according to the fourth embodiment of the present invention; Cross-sectional view along line BB of FIG. 23A Cross-sectional view along CC line of FIG. 23A FIG. 11 is a cross-sectional view of the vicinity of the planetary rollers of the planetary roller screw type linear motion mechanism according to the fifth embodiment of the present invention; Cross-sectional view along line BB of FIG. 24A Cross-sectional view along CC line of FIG. 24A Cross-sectional view of the vicinity of the planetary roller of the planetary roller screw type linear motion mechanism of the reference example Cross-sectional view along line BB of FIG. 25A Cross-sectional view along CC line of FIG. 25A

FIG. 1 shows an electric linear motion actuator 2 using the planetary roller screw type linear motion mechanism 1 of the first embodiment of the present invention. This electric linear motion actuator 2 includes an electric motor 3 , a reduction gear mechanism 4 that decelerates and transmits the rotation of the electric motor 3 , and an outer ring member 5 that transmits the rotation input from the electric motor 3 via the reduction gear mechanism 4 . and a planetary roller screw type linear motion mechanism 1 that converts and outputs the linear motion.

The reduction gear mechanism 4 includes an input gear 7 fixed to the motor shaft 6 of the electric motor 3, an output gear 9 fixed to the rotary shaft 10 of the planetary roller screw type linear motion mechanism 1, an input gear 7 and an output gear 9. and a gear case 11 for housing these

gears

7, 8 and 9. The gear case 11 consists of a base plate 12 and a cover 13 . The reduction gear mechanism 4 reduces the speed of the rotation input from the motor shaft 6 of the electric motor 3 to the input gear 7 by sequentially transmitting the rotation through the input gear 7, the intermediate gear 8, and the output gear 9, which have different numbers of teeth. The reduced rotation is output from the output gear 9 to the rotary shaft 10 .

As shown in FIGS. 2 and 3, the planetary roller screw type linear motion mechanism 1 includes a rotary shaft 10 that is rotationally driven by an electric motor 3 (see FIG. 1) and a hollow cylindrical outer ring member 5 that surrounds the rotary shaft 10. , a plurality of planetary rollers 14 arranged at intervals in the circumferential direction between the inner circumference of the outer ring member 5 and the outer circumference of the rotating shaft 10, and a plurality of rollers supporting the plurality of planetary rollers 14 so as to be rotatable. Shaft 15 , carrier 18 holding both ends (first end 16 and second end 17 ) of the plurality of roller shafts 15 in the axial direction, and outer ring member 5 are moved in parallel with the axial direction of rotating shaft 10 . and a housing 19 (see FIG. 2) that accommodates it. As shown in FIG. 1, the housing 19 is fixed to the axial front side surface of the base plate 12 .

Here, the direction parallel to the rotating shaft 10 is the axial direction, and the direction of movement of the outer ring member 5 when the outer ring member 5 moves toward the side where the projection length of the outer ring member 5 from the housing 19 is increased is the axial forward direction. The moving direction of the outer ring member 5 when the outer ring member 5 moves to the side where the projection length of the member 5 from the housing 19 becomes smaller is the axial rearward direction, the direction of rotation around the rotating shaft 10 is the circumferential direction, and The direction in which the distance changes is called the radial direction.

As shown in FIG. 3 , the plurality of planetary rollers 14 are in rolling contact with the outer circumference of the rotating shaft 10 . A contact portion of the rotating shaft 10 with the planetary roller 14 is a cylindrical surface. When the rotating shaft 10 rotates, each planetary roller 14 revolves around the rotating shaft 10 while rotating about the roller shaft 15 due to friction between the outer periphery of the rotating shaft 10 and the outer periphery of the planetary rollers 14 .

As shown in FIG. 2, a spiral ridge 20 is provided on the inner circumference of the outer ring member 5. As shown in FIG. The spiral ridge 20 is a ridge obliquely extending with a predetermined lead angle with respect to the circumferential direction. A plurality of circumferential grooves 21 that engage with the spiral ridges 20 are formed on the outer periphery of each planetary roller 14 at intervals in the axial direction. The interval between adjacent circumferential grooves 21 on the outer periphery of each planetary roller 14 in the axial direction is the same size as the pitch of the spiral ridges 20 . Here, the circumferential groove 21 having a lead angle of 0 degrees is provided on the outer periphery of the planetary roller 14, but instead of the circumferential groove 21, a spiral groove having a lead angle different from that of the spiral ridge 20 may be provided. .

The carrier 18 connects the first disk 22 and the second disk 23 by passing between the plurality of planetary rollers 14 and the first disk 22 and the second disk 23 that face each other in the axial direction with the plurality of planetary rollers 14 interposed therebetween. It has a plurality of connecting portions 24 that connect to each other. The connecting portion 24 is a columnar member extending in the axial direction between the planetary rollers 14 adjacent in the circumferential direction.

The axial front end of the connecting portion 24 is press-fitted into a press-fitting hole 25 formed in the first disk 22 and fixed, and the axial rear end of the connecting portion 24 is press-fitted into a press-fitting hole 26 formed in the second disk 23 . has been fixed. The connecting portion 24 fixes the first disk 22 and the second disk 23 to each other so that the first disk 22 and the second disk 23 do not move relative to each other in either the axial direction or the circumferential direction.

A first end portion 16 of the roller shaft 15 (an end portion on the front side in the axial direction in the figure) is held by a first elongated hole 31 formed in the first disc 22 so as to be movable in the radial direction. The second end 17 of the roller shaft 15 (the end on the rear side in the axial direction in the figure) is also held by a second elongated hole 32 formed in the second disc 23 so as to be radially movable.

As shown in FIG. 4, a second C-shaped ring spring 34 is stretched over the second end portion 17 of the roller shaft 15 in a state of being elastically expanded in diameter. The second end 17 of each roller shaft 15 is urged radially inward by the elastic restoring force of . Similarly, as shown in FIG. 2, a first C-shaped ring spring 33 is stretched over the first end portions 16 of the plurality of roller shafts 15 in a state of being elastically deformed to expand its diameter. The elastic restoring force of the C-shaped ring spring 33 urges the first end 16 of each roller shaft 15 radially inward. The outer circumference of each planetary roller 14 is pressed against the outer circumference of the rotating shaft 10 by the elastic restoring forces of the first C-shaped ring spring 33 and the second C-shaped ring spring 34 .

As shown in FIG. 2, the first disk 22 and the second disk 23 are formed in an annular shape through which the rotating shaft 10 is passed. Slide bearings 35 are mounted on the inner circumferences of the first disk 22 and the second disk 23 so as to be in sliding contact with the outer circumference of the rotating shaft 10 . The slide bearing 35 supports the carrier 18 rotatably around the rotary shaft 10 .

A radial bearing 36 is provided between the inner circumference of each planetary roller 14 and the outer circumference of the roller shaft 15 to support the planetary roller 14 so that it can rotate. The radial bearing 36 supports the outer circumference of the central portion of each roller shaft 15 (the portion between the first end portion 16 and the second end portion 17). The outer circumference of the central portion of each roller shaft 15 is a constant cylindrical surface whose outer diameter does not change along the axial direction. Needle rollers with retainers can be used as the radial bearings 36 . A thrust bearing 37 is incorporated between each planetary roller 14 and the second disk 23 to axially support the planetary roller 14 in a rotatable state.

As shown in FIG. 1, the outer ring member 5 is axially slidably supported on the inner surface of a housing hole 38 formed in the housing 19 . A shaft support member 39 is fixedly provided inside the housing 19 at a position spaced rearward in the axial direction from the outer ring member 5 . The shaft support member 39 is formed in an annular shape through which the rotating shaft 10 passes. A radial bearing 40 that rotatably supports the rotating shaft 10 is incorporated in the inner periphery of the shaft support member 39 .

A thrust bearing 41 is incorporated between the carrier 18 and the shaft support member 39 to axially support the carrier 18 so that it can revolve. A spacer 42 that revolves integrally with the carrier 18 is incorporated between the carrier 18 and the thrust bearing 41 .

The axially rearward movement of the shaft support member 39 is restricted by a snap ring 43 mounted on the inner circumference of the housing hole 38, and the carrier 18 is also restricted from axially rearward movement. . Further, the carrier 18 is restricted from moving forward in the axial direction by a retaining ring 44 provided at the axial front end of the rotary shaft 10 . As a result, the carrier 18 is restricted from moving forward and backward in the axial direction, and the planetary rollers 14 held by the carrier 18 are also restricted from moving in the axial direction.

As shown in FIG. 6, a plurality of first elongated holes 31 are provided at intervals in the circumferential direction. Each first slot 31 axially penetrates the first disc 22 , and the first end 16 of the roller shaft 15 is inserted into each first slot 31 .

As shown in FIG. 7, the first elongated hole 31 is elongated in the radial direction (vertical direction in the figure) and has a pair of longitudinal surfaces 45 that extend linearly in the radial direction. The pair of longitudinal surfaces 45 are flat surfaces arranged to face each other in the circumferential direction. On the outer periphery of the first end 16 of the roller shaft 15, there are a pair of first anti-rotation shaped portions 46, and the pair of first anti-rotation shaped portions 46 are adjacent to each other around the axis of the roller shaft 15. A pair of first partial cylindrical surfaces 47 are formed. The first anti-rotation shape portion 46 is a portion formed by cutting out a part of the outer circumference of the circular cross section by processing the outer circumference of the end portion of the roller shaft 15 . 15 is a portion having a shape capable of restricting its rotation. In this embodiment, the first anti-rotation portion 46 is a flat surface obtained by cutting the outer periphery of the roller shaft 15 along a plane parallel to the axial center of the roller shaft 15 . The pair of first anti-rotation shaped portions 46 are formed in parallel with the axis of the roller shaft 15 interposed therebetween (so-called width across flats).

The width dimension of the first long hole 31 (the spacing dimension between the pair of longitudinal surfaces 45) corresponds to the width dimension of the pair of first detent shaped portions 46 on the outer periphery of the first end portion 16. Also, the width dimension of the first long hole 31 is smaller than the outer diameter dimension of the roller shaft 15 . The roller shaft 15 is prevented from rotating by engaging the first anti-rotation shape portion 46 with the longitudinal surface 45 of the first elongated hole 31 (surface contact in this embodiment).

As shown in FIG. 8, a plurality of second elongated holes 32 are also provided at intervals in the circumferential direction. Each second slot 32 axially penetrates the second disc 23 , and the second end 17 of the roller shaft 15 is inserted into each second slot 32 .

As shown in FIG. 9, the second elongated hole 32 is elongated in the radial direction (vertical direction in the figure) and has a pair of longitudinal surfaces 48 that extend linearly in the radial direction. The pair of longitudinal surfaces 48 are flat surfaces that face each other in the circumferential direction. The outer circumference of the second end portion 17 of the roller shaft 15 is provided with a pair of second detent shaped portions 49 and adjacent to the pair of second detent shaped portions 49 around the axis of the roller shaft 15 . A pair of second partial cylindrical surfaces 50 are formed. Like the first anti-rotation shape portion 46 , the second anti-rotation shape portion 49 is a flat surface formed by cutting the outer periphery of the roller shaft 15 along a plane parallel to the axis of the roller shaft 15 . The pair of second detent shaped portions 49 are formed in parallel with the axis of the roller shaft 15 interposed therebetween.

The shape and dimensions of the second end 17 of the roller shaft 15 shown in FIG. 9 are the same as the shape and dimensions of the first end 16 of the roller shaft 15 shown in FIG. However, the angular position of the second detent shape portion 49 shown in FIG. 9 around the axis of the roller shaft 15 is different from the angular position of the first detent shape portion 46 shown in FIG. different. That is, as shown in FIGS. 10 to 12 , the first anti-rotation shape portion 46 and the second anti-rotation shape portion 49 are aligned in the normal direction of the first anti-rotation shape portion 46 and the normal direction of the second anti-rotation shape portion 49 . They are formed such that their line directions are different from each other. In this embodiment, the difference between the angular position of the first detent shape portion 46 about the axis of the roller shaft 15 and the angular position of the second detent shape portion 49 about the axis of the roller shaft 15 is 40° or more. It is set within a range of 50° or less (45° in the drawing). The four flat surfaces of the roller shaft 15 (the two first anti-rotation shaped portions 46 and the two second anti-rotation shaped portions 49) all face different directions.

As shown in FIG. 9 , the width dimension of the second elongated hole 32 (the spacing dimension between the pair of longitudinal surfaces 48 ) is a dimension corresponding to the outer diameter dimension of the roller shaft 15 . The width dimension of the second long hole 32 is wider than the width dimension of the first long hole 31 (see FIG. 7). ing. Of the second detent shape portion 49 and the second partial cylindrical surface 50 on the outer periphery of the second end portion 17 of the roller shaft 15 , only the second partial cylindrical surface 50 is in contact with the longitudinal surface 48 of the second elongated hole 32 . It is supported, and the second anti-rotation shape portion 49 is out of contact with the longitudinal surface 48 .

As shown in FIGS. 5 and 10, a second ring groove 52 with which the second C-shaped ring spring 34 engages is formed on the outer circumference of the second end 17 of the roller shaft 15 . Similarly, as shown in FIG. 10, the outer circumference of the first end 16 of the roller shaft 15 is formed with a first ring groove 51 with which the first C-shaped ring spring 33 (see FIG. 2) engages. there is The first anti-rotation shaped portion 46 is formed so as to cross the forming region of the first ring groove 51 in the axial direction and reach the end surface of the roller shaft 15 on the first end portion 16 side. The second anti-rotation shape portion 49 is also formed so as to extend axially across the forming region of the second ring groove 52 and reach the end surface of the roller shaft 15 on the second end portion 17 side.

In the roller shaft 15 shown in FIG. 10, when the direction of the roller shaft 15 is reversed so that the positions of the first end 16 and the second end 17 are exchanged, the shape and dimensions of the second end 17 after the reversal are as follows. Symmetry such that the shape and dimensions of the first end 16 before inversion are identical to the shape and dimensions of the first end 16 after inversion, and the shape and dimensions of the first end 16 after inversion are the same as the shape and dimensions of the second end 17 before inversion have sex.

An operation example of the electric linear motion actuator 2 will be described.

When the motor shaft 6 of the electric motor 3 shown in FIG. When the rotating shaft 10 rotates, the rotation is transmitted to the planetary rollers 14 that are in rolling contact with the outer periphery of the rotating shaft 10 , and each planetary roller 14 revolves around the rotating shaft 10 while rotating about the roller shaft 15 . At this time, the engagement between the circumferential groove 21 on the outer circumference of the planetary roller 14 and the spiral ridge 20 on the inner circumference of the outer ring member 5 causes the planetary roller 14 and the outer ring member 5 to move relative to each other in the axial direction. is restricted from moving in the axial direction together with the carrier 18 , the planetary rollers 14 do not move axially with respect to the housing 19 and the outer ring member 5 moves axially with respect to the housing 19 . In this manner, the planetary roller screw type linear motion mechanism 1 converts the rotation input from the electric motor 3 to the rotary shaft 10 into linear motion of the outer ring member 5 .

13 and 14 show an electric brake device using the electric linear motion actuator 2 having the above configuration. This electric brake device includes a brake disc 60 that rotates together with a wheel (not shown), a mounting bracket 61 that is fixed to the vehicle body so as not to move in the axial direction with respect to the brake disc 60, and a A caliper body 62 slidably supported in parallel with the axial direction of the brake disc 60, an inner side brake pad 63 and an outer side brake pad 64 axially opposed to each other with the brake disc 60 interposed therebetween, and an inner side brake pad. and an electric linear motion actuator 2 that moves 63 in the axial direction. The inner side brake pad 63 and the outer side brake pad 64 are each held by a mounting bracket 61 so as to be axially movable and circumferentially immovable.

The caliper body 62 has a claw portion 65 that axially faces the rear surface of the outer brake pad 64 and an outer shell portion 66 that faces the outer diameter side of the brake disc 60 . The outer shell portion 66 is formed integrally with the housing 19 of the electric linear motion actuator 2 . The outer shell portion 66 of the caliper body 62 and the housing 19 of the electric linear motion actuator 2 may be formed separately and then integrated with bolts or the like. The outer ring member 5 is arranged behind the inner side brake pad 63 so that the inner side brake pad 63 moves integrally with the outer ring member 5 when the outer ring member 5 moves.

An end portion of the outer ring member 5 on the brake disc 60 side is formed with a detent groove 68 that engages with a detent projection 67 formed on the back surface of the inner side brake pad 63 . The engagement of the groove 68 prevents rotation of the outer ring member 5 .

An operation example of this electric brake device will be explained. The outer ring member 5 of the electric linear motion actuator 2 axially presses the back surface of the inner side brake pad 63 to press the inner side brake pad 63 against the side surface of the brake disc 60 . At this time, the caliper body 62 slides relative to the mounting bracket 61 due to the axial reaction force that the outer ring member 5 receives from the inner side brake pad 63 , and the claw portion 65 of the caliper body 62 slides along the back surface of the outer side brake pad 64 . By pressing, the outer side brake pad 64 is pressed against the side surface of the brake disc 60 . In this way, the inner side brake pad 63 and the outer side brake pad 64 are pressed against the brake disc 60 , and braking force is generated in the brake disc 60 by friction between the contact surfaces of the brake pads and the brake disc 60 .

In the planetary roller screw type linear motion mechanism 1 described above, as shown in FIGS. 2, the roller shaft 15 is rotated together with the planetary roller 14 (so-called ) can be prevented. Therefore, it is possible to prevent wear of the contact portions of the roller shaft 15 with the C-shaped ring springs 33 and 34, and to prevent idle rotation of the rotating shaft 10 caused by the wear.

In addition, as shown in FIGS. 8 and 9, the planetary roller screw type linear motion mechanism 1 is formed with a wide second elongated hole 32. Therefore, when the planetary roller screw type linear motion mechanism 1 is produced, First, the carrier 18 composed of the first disk 22, the second disk 23, and the connecting portion 24 shown in FIG. It can be inserted into the first long hole 31 in order. Moreover, as shown in FIGS. 10 to 12, since the shape and dimensions of the first end 16 of the roller shaft 15 and the shape and dimensions of the second end 17 of the roller shaft 15 are the same, the roller shaft 15 can be When the roller shaft 15 is inserted into the second long hole 32 and the first long hole 31 in order, it is not necessary to distinguish between the front and rear directions of the roller shaft 15 . Therefore, the work of assembling the roller shaft 15 of the planetary roller 14 to the carrier 18 can be easily automated.

Moreover, as shown in FIGS. 10 to 12, the planetary roller screw type linear motion mechanism 1 has a plane parallel to the axis of the roller shaft 15 as a first anti-rotation shape portion 46 and a second anti-rotation shape portion 49. Since the flat surface of the shape obtained by cutting the outer periphery of the roller shaft 15 along the .theta. In addition, it is possible to prevent the roller shaft 15 from rotating. In addition, the reduction in the cross-sectional area of the first end 16 and the second end 17 of the roller shaft 15 due to the formation of the first anti-rotation shape portion 46 and the second anti-rotation shape portion 49 is minimized, The strength of the first end portion 16 and the second end portion 17 of the shaft 15 can be easily ensured. Further, the first anti-rotation shape portion 46 and the second anti-rotation shape portion 49 can be processed with high accuracy at low processing cost.

10 to 12, the planetary roller screw type linear motion mechanism 1 has a difference between the angular position of the first anti-rotation shaped portion 46 and the angular position of the second anti-rotation shaped portion 49 (in the figure, 45°) is set large, so when the first anti-rotation shape portion 46 is engaged with the longitudinal surface 45 of the first elongated hole 31 of the first disk 22 as shown in FIG. 2, it is possible to reliably arrange the second partial cylindrical surface 50 at the position of the longitudinal surface 48 of the second elongated hole 32 of the second disk 23. As shown in FIG.

10 to 12, the planetary roller screw type linear motion mechanism 1 has a difference between the angular position of the first anti-rotation shape portion 46 and the angular position of the second anti-rotation shape portion 49 of 40°. Since it is set to 50° or less (45° in the figure), as shown in FIG. It is possible to stabilize the engagement between the ring spring 34 and the second ring groove 52 .

That is, for example, as shown in FIGS. 23A to 23C, it is possible to set the difference between the angular position of the first detent shape portion 46 and the angular position of the second detent shape portion 49 to 90°. In this case, as shown in FIG. 23A, the position of the second detent shape portion 49 at the second end portion 17 and the engagement position of the second C-shaped ring spring 34 at the second ring groove 52 is at the same position (upper position of the second end portion 17 in the figure), the engagement allowance of the second C-shaped ring spring 34 with respect to the second ring groove 52 becomes extremely small or disappears, and the second C-shaped ring spring 34 The engagement between the ring spring 34 and the second ring groove 52 may become unstable. On the other hand, as shown in FIGS. 10 to 12, the difference between the angular position of the first detent shape portion 46 and the angular position of the second detent shape portion 49 is 40° or more and 50° or less (45° in the drawings). ), as shown in FIG. can be stabilized.

15A to 15C show a second embodiment of the invention. The second embodiment differs from the first embodiment only in the partial configuration of the roller shaft 15, and the rest of the configuration is the same. Therefore, parts corresponding to those in the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

As shown in FIG. 15B , on the outer periphery of the first end portion 16 of the roller shaft 15 , a first anti-rotation shape portion is formed by cutting the outer periphery of the roller shaft 15 along a plane parallel to the axial center of the roller shaft 15 . 46 and a first partial cylindrical surface 47 adjacent to the first detent shape portion 46 around the axis of the roller shaft 15 are formed. The first detent shape portion 46 is formed only at one location on the outer circumference of the first end portion 16 of the roller shaft 15 (so-called D-cut).

The width dimension of the first long hole 31 (the spacing dimension between the pair of longitudinal surfaces 45) corresponds to the width dimension in the direction perpendicular to the first detent shape portion 46 (flat surface) of the first end portion 16. ing. Also, the width dimension of the first long hole 31 is smaller than the outer diameter dimension of the roller shaft 15 . The roller shaft 15 is prevented from rotating by engaging the first anti-rotation shape portion 46 with the longitudinal surface 45 of the first elongated hole 31 .

As shown in FIG. 15C , on the outer circumference of the second end 17 of the roller shaft 15 , a second anti-rotation shaped portion is formed by cutting the outer circumference of the roller shaft 15 along a plane parallel to the axial center of the roller shaft 15 . 49 and a second partial cylindrical surface 50 adjacent to the second detent shape portion 49 around the axis of the roller shaft 15 are formed. The second detent shape portion 49 is formed only at one location on the outer circumference of the second end portion 17 of the roller shaft 15 .

The shape and dimensions of the second end 17 of the roller shaft 15 shown in FIG. 15C are the same as the shape and dimensions of the first end 16 of the roller shaft 15 shown in FIG. 15B. However, the angular position around the axis of the roller shaft 15 of the second detent shape portion 49 shown in FIG. 15C is different from the angular position around the axis of the roller shaft 15 of the first detent shape portion 46 shown in FIG. 15B. different. That is, as shown in FIGS. 16 to 18 , the first anti-rotation shape portion 46 and the second anti-rotation shape portion 49 are aligned in the normal direction of the first anti-rotation shape portion 46 and the normal direction of the second anti-rotation shape portion 49 . They are formed such that their line directions are different from each other. In this embodiment, the difference between the angular position of the first detent shape portion 46 about the axis of the roller shaft 15 and the angular position of the second detent shape portion 49 about the axis of the roller shaft 15 is 40° or more. It is set within a range of 50° or less (45° in the figure).

As shown in FIG. 15C , the width dimension of the second elongated hole 32 (the spacing dimension between the pair of longitudinal surfaces 48 ) is a dimension corresponding to the outer diameter dimension of the roller shaft 15 . The width dimension of the second long hole 32 is wider than the width dimension of the first long hole 31 shown in FIG. 15B. As shown in FIG. 15C , of the second detent shape portion 49 and the second partial cylindrical surface 50 on the outer periphery of the second end portion 17 of the roller shaft 15 , only the second partial cylindrical surface 50 is located in the second elongated hole 32 . It is supported in contact with the longitudinal surface 48 , and the second detent shape portion 49 is out of contact with the longitudinal surface 48 .

This second embodiment has the same effects as the first embodiment.

19A to 19C show a third embodiment of the invention. The third embodiment differs from the second embodiment only in the difference between the angular position of the first anti-rotation shape portion 46 and the angular position of the second anti-rotation shape portion 49, and the rest of the configuration is the same. Therefore, portions corresponding to those in the second embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

The shape and dimensions of the second end 17 of the roller shaft 15 shown in FIG. 19C are the same as the shape and dimensions of the first end 16 of the roller shaft 15 shown in FIG. 19B. However, the angular position around the axis of the roller shaft 15 of the second detent shape portion 49 shown in FIG. 19C is different from the angular position around the axis of the roller shaft 15 of the first detent shape portion 46 shown in FIG. 19B. different. That is, as shown in FIGS. 20 to 22, the angular position of the first anti-rotation shape portion 46 about the axis of the roller shaft 15 and the angular position of the second anti-rotation shape portion 49 about the axis of the roller shaft 15 is set in the range of 130° or more and 140° or less (135° in the drawing).

The third embodiment has the same effects as the first embodiment.

23A to 23C show a fourth embodiment of the invention. The fourth embodiment differs from the first embodiment only in the difference between the angular position of the first anti-rotation shape portion 46 and the angular position of the second anti-rotation shape portion 49, and the rest of the configuration is the same. Therefore, parts corresponding to those in the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

The shape and dimensions of the second end 17 of the roller shaft 15 shown in FIG. 23C are the same as the shape and dimensions of the first end 16 of the roller shaft 15 shown in FIG. 23B. However, the angular position around the axis of the roller shaft 15 of the second detent shape portion 49 shown in FIG. 23C is different from the angular position around the axis of the roller shaft 15 of the first detent shape portion 46 shown in FIG. 23B. different. That is, the difference between the angular position of the first detent shape portion 46 about the axis of the roller shaft 15 and the angular position of the second detent shape portion 49 about the axis of the roller shaft 15 is set to 90°. there is

In this fourth embodiment, as in the first embodiment, the carrier 18 shown in FIG. 23A is first assembled, and then the roller shaft 15 is inserted into the second elongated hole 32 and the first elongated hole from the second disc 23 side. 31 can be inserted in sequence. Moreover, since the shape and dimensions of the first end portion 16 of the roller shaft 15 and the shape and dimensions of the second end portion 17 of the roller shaft 15 are the same, the roller shaft 15 can be divided into the second elongated hole 32 and the first elongated hole 31 . There is no need to distinguish between the front and rear directions of the roller shafts 15 when inserting them in order. Therefore, the work of assembling the roller shaft 15 of the planetary roller 14 to the carrier 18 can be easily automated.

Also, as in the first embodiment, the difference between the angular position of the first detent shape portion 46 and the angular position of the second detent shape portion 49 is large. When the first anti-rotation shape portion 46 is engaged with the longitudinal surface 45 of the first elongated hole 31, as shown in FIG. It is possible to dispose the second partial cylindrical surface 50 on the .

　Figures 24A to 24C show a fifth embodiment of the present invention. The fifth embodiment differs from the first embodiment only in the shapes of the first anti-rotation shape portion 46 and the second anti-rotation shape portion 49, and the rest of the configuration is the same. Therefore, parts corresponding to those in the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

As shown in FIG. 24B, on the outer periphery of the first end portion 16 of the roller shaft 15, there are a pair of first anti-rotation shaped portions 46, and the roller shaft 15 for each of the pair of first anti-rotation shaped portions 46. A pair of first partial cylindrical surfaces 47 are formed adjacent to each other around the axis. The first anti-rotation shape portion 46 is a portion formed by cutting out a part of the outer circumference of the circular cross section by processing the outer circumference of the end portion of the roller shaft 15. As shown in FIG. 31 has a shape capable of restricting the rotation of the roller shaft 15 when pressed against the longitudinal surface 45 of the roller shaft 31 . In this embodiment, the first anti-rotation shape portion 46 is a groove that extends parallel to the axis of the roller shaft 15 on the outer periphery of the roller shaft 15 .

As shown in FIG. 24C, on the outer periphery of the second end 17 of the roller shaft 15, there are a pair of second anti-rotation shaped portions 49 and roller shaft 15 with respect to each of the pair of second anti-rotation shaped portions 49. As shown in FIG. A pair of second partial cylindrical surfaces 50 are formed adjacent to each other around the axis. As with the first anti-rotation shape portion 46, the second anti-rotation shape portion 49 has a shape obtained by partially cutting the outer circumference of the circular end section of the roller shaft 15 (the rotation of the roller shaft 15 when pressed against an imaginary plane). It is a shape that can regulate the

The shape and dimensions of the second end 17 of the roller shaft 15 shown in FIG. 24C are the same as the shape and dimensions of the first end 16 of the roller shaft 15 shown in FIG. 24B. However, the angular position around the axis of the roller shaft 15 of the second detent shape portion 49 shown in FIG. 24C is different from the angular position around the axis of the roller shaft 15 of the first detent shape portion 46 shown in FIG. 24B. different.

That is, as shown in FIGS. 24A to 24C, the first anti-rotation shape portion 46 and the second anti-rotation shape portion 49 are positioned at the angular positions (first ) and the angular position of the second detent shape portion 49 about the axis of the roller shaft 15 (the second detent shape). The normal direction of the plane when the shape portion 49 is engaged with the virtual plane) is formed so as to be different from each other. In this embodiment, the difference between the angular position of the first detent shape portion 46 about the axis of the roller shaft 15 and the angular position of the second detent shape portion 49 about the axis of the roller shaft 15 is 40° or more. It is set within a range of 50° or less (45° in the drawing).

The fifth embodiment has the same effects as the first embodiment.

In each of the above embodiments, of the pair of

discs

22 and 23 that constitute the carrier 18, the axially front disc is the first disc 22 (the disc in which the first elongated hole 31 is formed), and the axially rear disc is the second disk 23 (the disk in which the second elongated hole 32 is formed), but the front and rear in the axial direction may be reversed. That is, of the pair of

discs

22 and 23, the disc on the rear side in the axial direction is the first disc 22 (the disc in which the first long hole 31 is formed), and the disc on the front side in the axial direction is the second disc 23 (the second long hole). It is also possible to use a disk with holes 32 formed therein.

The embodiments disclosed this time should be considered illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the meaning and range of equivalents of the scope of the claims.

1 Planetary roller screw type linear motion mechanism 3 Electric motor 5 Outer ring member 10 Rotating shaft 14 Planetary roller 15 Roller shaft 16 First end 17 Second end 20 Spiral ridge 21 Circumferential groove 22 First disk 23 Second disk 24 Connecting portion 31 First elongated hole 32 Second elongated hole 33 First C-shaped ring spring 34 Second C-shaped ring spring 45 Longitudinal surface 46 First detent shape portion 47 First partial cylindrical surface 48 Longitudinal surface 49 Second Whirl-stop portion 50 Second partial cylindrical surface 51 First ring groove 52 Second ring groove 63 Inner side brake pad

Claims

a rotating shaft (10);
a hollow cylindrical outer ring member (5) surrounding the rotating shaft (10);
a plurality of planetary rollers (14) arranged at intervals in the circumferential direction between the inner circumference of the outer ring member (5) and the outer circumference of the rotating shaft (10);
a spiral ridge (20) provided on the inner periphery of the outer ring member (5);
a spiral or circumferential groove (21) provided on the outer circumference of each planetary roller (14) to engage with the spiral ridge (20);
a plurality of roller shafts (15) rotatably supporting the plurality of planetary rollers (14);
A first disk (22) and a second disk (23) axially opposed to each other with the plurality of planetary rollers (14) therebetween, and the first disk (22) and the second disk (23) passing between the plurality of planetary rollers (14). 22) and a carrier (18) with a connection (24) connecting said second disc (23);
The first disk (22) has a plurality of first elongated holes (31) circumferentially spaced apart for holding the first ends (16) of the plurality of roller shafts (15) movably in the radial direction. formed in
The second disk (23) has a plurality of second elongated holes (32) circumferentially spaced apart from each other for radially movably holding the second ends (17) of the plurality of roller shafts (15). In the planetary roller screw type linear motion mechanism formed in
The width dimension of the second long hole (32) is wider than the width dimension of the first long hole (31),
On the outer periphery of the first end (16) of the roller shaft (15), there is provided a first anti-rotation shape portion (46), and the roller shaft (15) is positioned against the first anti-rotation shape portion (46). A first partial cylindrical surface (47) adjacent around the axis is formed, and the first anti-rotation shaped portion (46) engages the longitudinal surface (45) of the first elongated hole (31). The roller shaft (15) is detented so as not to rotate;
On the outer periphery of the second end (17) of the roller shaft (15), there is provided a second anti-rotation shape portion (49), and the roller shaft (15) is positioned against the second anti-rotation shape portion (49). A second partial cylindrical surface (50) is formed adjacent about the axis, said second end (17) having the same shape and dimensions as said first end (16), but , the angular position of the second anti-rotation shape portion (49) around the axis of the roller shaft (15) and the angular position of the first anti-rotation shape portion (46) around the axis of the roller shaft (15) Differently, only the second partial cylindrical surface (50) out of the second anti-rotation shape portion (49) and the second partial cylindrical surface (50) is the longitudinal surface (48) of the second long hole (32). A planetary roller screw type linear motion mechanism characterized in that it is supported in contact with the .
The first anti-rotation shape part (46) and the second anti-rotation shape part (49) are formed by cutting the outer periphery of the roller shaft (15) along a plane parallel to the axis of the roller shaft (15). 2. The planetary roller screw type linear motion mechanism according to claim 1, wherein the flat surface is
The angular position of the first detent shape portion (46) around the axis of the roller shaft (15) and the angular position of the second detent shape portion (49) around the axis of the roller shaft (15). 3. The planetary roller screw type linear motion mechanism according to claim 1 or 2, wherein the difference between is set in the range of 40° or more and 140° or less.
a first C-shaped ring spring (33) biasing said first end (16) of said roller shaft (15) radially inward; and said second end (17) of said roller shaft (15) ) radially inwardly biasing the second C-shaped ring spring (34);
A first ring groove (51) with which the first C-shaped ring spring (33) engages is formed on the outer periphery of the first end (16) of the roller shaft (15),
A second ring groove (52) with which the second C-shaped ring spring (34) engages is formed on the outer periphery of the second end (17) of the roller shaft (15),
The angular position of the first detent shape portion (46) around the axis of the roller shaft (15) and the angular position of the second detent shape portion (49) around the axis of the roller shaft (15). 4. The planetary roller screw type linear motion mechanism according to any one of claims 1 to 3, wherein the difference between is set to 40° or more and 50° or less or 130° or more and 140° or less.
The first anti-rotation shape part (46) is a flat pair formed on the outer periphery of the first end (16) of the roller shaft (15) in parallel with the center of the roller shaft (15) interposed therebetween. is a surface,
The second anti-rotation shaped part (49) is a pair of flat flat parts formed on the outer periphery of the second end (17) of the roller shaft (15) in parallel with the center of the roller shaft (15) interposed therebetween. The planetary roller screw type linear motion mechanism according to any one of claims 1 to 4, which is a surface.
The first anti-rotation shaped portion (46) is formed only at one location on the outer periphery of the first end (16) of the roller shaft (15),
5. The planet according to any one of claims 1 to 4, wherein the second anti-rotation shaped portion (49) is formed only at one location on the outer periphery of the second end (17) of the roller shaft (15). Roller screw type linear motion mechanism.
A planetary roller screw type linear motion mechanism (1) according to any one of claims 1 to 6;
an electric motor (3) that rotationally drives the rotary shaft (10) of the planetary roller screw type linear motion mechanism (1);
and a brake pad (63) axially pressed by the outer ring member (5) of the planetary roller screw type linear motion mechanism (1).