JP7301638B2 - Bearing mechanism and reducer - Google Patents

Description

The present invention relates to bearing mechanisms and reduction gears.

Patent Document 1 discloses a bearing mechanism in which a roller bearing (crank bearing) is arranged on the inner peripheral surface of a base member (carrier), and a regulating member is provided next to the roller bearing in the axial direction of the inner peripheral surface. . Since the rolling elements of the roller bearing are cylindrical and extend in the axial direction of the inner peripheral surface, the roller bearing can move in the axial direction of the inner peripheral surface with respect to the base member. On the other hand, the restricting member restricts the movement of the roller bearing in the axial direction.

JP 2016-130536 A

However, in the conventional bearing mechanism, since only the retainer of the roller bearing that retains the plurality of rolling elements contacts the restricting member, there is a problem that the load concentrates on the retainer.

SUMMARY OF THE INVENTION The present invention provides a bearing mechanism and a speed reducer capable of alleviating concentration of load on a retainer to protect the retainer.

A bearing mechanism according to an aspect of the present invention includes a roller bearing having a plurality of cylindrical rolling elements and a retainer that holds the plurality of rolling elements; a base member having an inner peripheral surface; a regulating member that restricts axial movement of the roller bearing; and a plurality of the rolling elements arranged on the inner peripheral surface. The regulating member is formed in a cylindrical shape extending in the axial direction and is arranged in the circumferential direction of the inner peripheral surface, and the restricting member is attached next to the roller bearing in the axial direction on the inner peripheral surface and is axially attached to the rolling element. The retainer includes an annular portion disposed along the inner peripheral surface and flange portions projecting radially from both axial ends of the annular portion and positioned on both sides of the rolling elements in the axial direction. and the regulating member has a main body attached to the inner peripheral surface, and a contact projection projecting from the facing surface of the main body facing the roller bearing in the axial direction and contacting the rolling element. The length of protrusion of the contact protrusion in the axial direction is greater than the thickness of the flange in the axial direction.

With this configuration, when the roller bearing is axially pressed against the regulating member, at least the regulating member comes into contact with the rolling elements. Therefore, compared to the case where the restricting member contacts only the retainer, it is possible to reduce the load acting on the retainer as the roller bearing is pressed against the restricting member. That is, it is possible to alleviate the concentration of the load on the retainer of the roller bearing.

The roller bearing including the rolling elements described above is easy to move in the axial direction of the inner peripheral surface with respect to the base member and is easily pressed against the regulating member. , the load concentration on the retainer of the roller bearing can be effectively relieved.

By configuring in this way, even if the contact projection (tip thereof) of the regulating member comes into contact with the rolling element of the roller bearing in the axial direction, it is arranged between the main body portion of the regulating member and the rolling element in the axial direction. It is possible to suppress or prevent the collar portion of the retainer from contacting the main body portion of the regulating member. Therefore, the retainer can be protected more reliably.

A bearing mechanism according to another aspect of the present invention is a roller bearing having a plurality of cylindrical rolling elements and a cage that holds the plurality of rolling elements, and a roller bearing that contacts the rolling elements of the roller bearing. a base member having an inner peripheral surface; a regulating member that restricts axial movement of the roller bearing; and a plurality of the rolling elements arranged on the inner peripheral surface. and arranged in the circumferential direction of the inner peripheral surface, and the restricting member is mounted next to the roller bearing in the axial direction on the inner peripheral surface and is axially aligned with the rolling element The retainer includes an annular portion disposed along the inner peripheral surface, and flange portions projecting radially from both axial ends of the annular portion and positioned on both sides of the rolling elements in the axial direction. and the regulating member has an accommodating recess that is recessed from an end surface facing the roller bearing in the axial direction and accommodates the flange.

With this configuration, the end surface of the regulating member is placed between the regulating member and the rolling elements of the roller bearing in a state in which the flange portion of the retainer, which is arranged between the regulating member and the rolling elements in the axial direction, is accommodated in the accommodation recess of the regulating member. can be contacted. Thereby, even if the restricting member comes into contact with the roller bearing in the axial direction, it is possible to suppress or prevent the collar portion of the retainer from contacting the restricting member. Therefore, the retainer can be protected more reliably.

In the above configuration, the retainer includes an annular portion arranged along the inner peripheral surface, and radially projecting from both axial ends of the annular portion, and positioned on both sides of the rolling element in the axial direction. A first flange portion having a flange portion and arranged between the restricting member and the rolling element in the axial direction of the flange portion has a radial length of the first flange portion in the axial direction of the flange portion. It may be smaller than the length in the radial direction of the second flange portion that positions the rolling element between the first flange portion and the second flange portion.

By configuring in this way, the area of the rolling element covered by the first flange in the axial direction is reduced. That is, the area of the rolling element facing the regulating member in the axial direction without interposing the first collar portion is increased. As a result, it is possible to secure the area of the rolling element that contacts the regulating member, and to bring the regulating member into contact with the rolling element stably.

A bearing mechanism according to another aspect of the present invention includes a base member having an inner peripheral surface, and a plurality of cylindrical bearings extending in the axial direction of the inner peripheral surface and arranged in the circumferential direction of the inner peripheral surface. a rolling element, an annular portion disposed along the inner peripheral surface, and a plurality of flange portions protruding radially from both axial ends of the annular portion and positioned on both sides of the rolling element in the axial direction. wherein the radial length of the first flange portion of the flange portion of the cage is between the first flange portion and the first flange portion in the axial direction of the flange portion of the cage. A roller bearing smaller than the radial length of the second flange portion that positions the rolling elements in the inner peripheral surface so that the first flange portion is positioned between the rolling elements in the axial direction. a main body mounted next to the roller bearing in the axial direction; a restricting member that has a contact protrusion larger than the thickness of the flange and restricts axial movement of the roller bearing by coming into contact with the rolling element.

With this configuration, when the roller bearing is axially pressed against the regulating member, the contact projections of the regulating member come into contact with the rolling elements. Therefore, compared to the case where the restricting member contacts only the retainer, it is possible to reduce the load acting on the retainer as the roller bearing is pressed against the restricting member. That is, it is possible to alleviate the concentration of the load on the retainer of the roller bearing.

A speed reducer according to an aspect of the present invention includes the bearing mechanism, a rotating shaft rotatably supported on the inner peripheral surface via the roller bearing, and the base member arranged inside the bearing mechanism so as to be relatively rotatable. and an oscillating gear arranged inside the outer cylinder and oscillatingly rotated with the rotation of the rotating shaft. The rotary shaft is a crankshaft that relatively rotates the outer cylinder and the base member at a speed slower than the rotation speed of the rotary shaft based on the oscillating rotation of the oscillating gear.

With this configuration, the speed reducer includes a bearing mechanism capable of protecting the retainer of the roller bearing, so the reliability of the speed reducer can be improved.

In the bearing mechanism and speed reducer described above, the concentration of the load on the retainer of the roller bearing can be alleviated to protect the retainer.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the reduction gear concerning 1st embodiment of this invention. 2 is an enlarged cross-sectional view showing a first regulating member and its vicinity in the speed reducer of FIG. 1; FIG. 3 is an enlarged cross-sectional view showing a first regulating member in FIG. 2 and its vicinity; FIG. FIG. 6 is an enlarged cross-sectional view showing the essential parts of the speed reducer according to the second embodiment of the present invention; 5 is a cross-sectional view taken along line VV in FIG. 4; FIG.

[First embodiment]
A first embodiment of the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the speed reducer 1 according to the present embodiment includes an outer cylinder 2, a carrier (base member) 3 and an oscillating gear 4 disposed inside the outer cylinder 2, and a carrier 3 and an oscillating gear. 4, a crankshaft (roller bearing) 7 interposed between the inner peripheral surfaces 31e, 32e of the carrier 3 and the crankshaft 5, and a regulating member 6 mounted on the carrier 3. Prepare.
The carrier 3, the crank bearing 7, and the restricting member 6 constitute a bearing mechanism 100 according to this embodiment. The bearing mechanism 100 is a mechanism that restricts axial movement of the crank bearing 7 by the restricting member 6 .

The outer cylinder 2 is formed in a cylindrical shape centered on the axis C1. The outer cylinder 2 has a plurality of internal teeth 21 on its inner periphery. Specifically, the outer cylinder 2 includes a cylindrical body cylinder portion 22 and a plurality of internal teeth pins 23 attached to the inner periphery of the body cylinder portion 22 and arranged at equal intervals in the circumferential direction of the body cylinder portion 22 . have. The internal tooth pin 23 forms the internal tooth 21 described above. The internal tooth pin 23 is formed in a cylindrical shape extending in the direction of the axis C1 of the outer cylinder 2 .

The carrier 3 is arranged inside the outer cylinder 2 . The carrier 3 is relatively rotatable with respect to the outer cylinder 2 around the axis C1. Specifically, the speed reducer 1 includes a main bearing B<b>1 provided between the inner circumference of the outer cylinder 2 and the outer circumference of the carrier 3 . Two main bearings B1 are provided at intervals in the direction of the axis C1. The two main bearings B1 are located on both sides of the inner tooth 21 of the outer cylinder 2 in the direction of the axis C1. Main bearing B<b>1 allows relative rotation between outer cylinder 2 and carrier 3 .

The carrier 3 is configured to sandwich an oscillating gear 4, which will be described later, in the direction of the axis C1. The carrier 3 has a first member 31 and a second member 32 aligned in the direction of the axis C1. The carrier 3 also has a shaft portion 33 arranged between the first and second members 31 and 32 in the direction of the axis C1. A space for disposing the oscillating gear 4 is formed between the first member 31 and the second member 32 by the shaft portion 33 . A plurality (for example, three) of the shaft portions 33 are arranged at intervals in the circumferential direction of the carrier 3 . The shaft portion 33 may be formed integrally with the second member 32 as illustrated, or may be formed integrally with the first member 31, for example.
The first member 31 and the second member 32 are fastened together by a fastening member T1 such as a screw. In the illustrated example, the fastening member T1 fastens the first member 31 and the shaft portion 33 formed integrally with the second member 32, but the fastening member T1 is not limited to this.

The carrier 3 is formed with central holes 31a and 32a penetrating in the direction of the axis C1. Central holes 31a and 32a are formed in the first member 31 and the second member 32, respectively. The central holes 31a, 32a are located at the central portion of the carrier 3 in the radial direction. The central holes 31a, 32a may be holes centered on the axis C1, for example.

The carrier 3 has insertion holes 31b, 32b into which the crankshaft 5, which will be described later, is inserted. Insertion holes 31b and 32b are formed in the first member 31 and the second member 32, respectively. The axes of the two insertion holes 31b and 32b formed in the first member 31 and the second member 32 are aligned with each other. One of the insertion holes 31b, 32b of the first and second members 31, 32 does not have to penetrate, for example. The insertion holes 31 b and 32 b of this embodiment pass through both the first member 31 and the second member 32 .

Inner peripheral surfaces 31e, 32e of the insertion holes 31b, 32b are circular when viewed from the axial direction. The inner peripheral surfaces 31e, 32e of the insertion holes 31b, 32b have female threaded portions 31f, 32f. The female threaded portions 31f and 32f are formed at the ends of the carrier 3 in the direction of the axis C1 in the insertion holes 31b and 32b. Specifically, the female threaded portions 31f and 32f are formed on the outer ends 31d and 32d of the first and second members 31 and 32 located outside in the arrangement direction of the first and second members 31 and 32, respectively.

In addition, the inner peripheral surfaces 31e, 32e of the insertion holes 31b, 32b have stepped portions 31g, 32g and radial support portions 31h, 32h. The stepped portions 31g and 32g are surfaces facing the outside of the carrier 3 in the direction of the axis C1. The radial support portions 31h and 32h are surfaces that radially support the crankshaft 5, which will be described later. The radial support portions 31h and 32h are smaller in diameter than the female screw portions 31f and 32f. The stepped portions 31g and 32g and the radial support portions 31h and 32h are formed on both the first and second members 31 and 32. As shown in FIG.

The female screw portions 31f and 32f, the stepped portions 31g and 32g, and the radial support portions 31h and 32h are arranged in this order toward the inside of the carrier 3 from both ends (outer ends 31d and 32d) of the carrier 3 in the direction of the axis C1. . Specifically, the female screw portion 31f, the step portion 31g, and the radial support portion 31h of the first member 31 are arranged in this order from the outer end portion 31d of the first member 31 toward the inner end portion 31c. The female threaded portion 32f, the stepped portion 32g, and the radial support portion 32h formed on the second member 32 are arranged in this order from the outer end portion 32d toward the inner end portion 32c of the second member 32. As shown in FIG.

The crankshaft 5 is rotatably supported by the inner peripheral surfaces 31e, 32e of the insertion holes 31b, 32b of the carrier 3 via the crank bearings 7 .
Specifically, the crankshaft 5 has first and second journal portions 51 and 52 . The axes of the first and second journal portions 51 and 52 are aligned with each other. The first and second journal portions 51 and 52 are spaced apart from each other in the axial direction of the crankshaft 5 . The first journal portion 51 is rotatably supported by the radial support portion 31 h of the insertion hole 31 b of the first member 31 . Also, the second journal portion 52 is rotatably supported by the radial support portion 32h of the insertion hole 32b of the second member 32 .

Further, the crankshaft 5 has a small diameter portion 53 having a diameter smaller than that of the first and second journal portions 51 and 52 . The axis of the small diameter portion 53 coincides with the axes of the first and second journal portions 51 and 52 . The small diameter portion 53 axially extends from the first journal portion 51 so that the first journal portion 51 is positioned between the second journal portion 52 in the axial direction of the crankshaft 5 . A portion of the small diameter portion 53 is positioned outside the carrier 3 in the axial direction (specifically, outside the outer end portion 31d of the first member 31). The small diameter portion 53 may be omitted, and for example, a portion of the first journal portion 51 may extend to the outside of the carrier 3 in the axial direction.

Further, the crankshaft 5 has an eccentric portion 54 that is eccentric with respect to the first and second journal portions 51 and 52 and the small diameter portion 53 . The eccentric portion 54 is positioned between the first and second journal portions 51 and 52 in the axial direction of the crankshaft 5 . The eccentric portion 54 is arranged in the space between the first member 31 and the second member 32 of the carrier 3 . The eccentric portion 54 of this embodiment has a first eccentric portion 54A and a second eccentric portion 54B that are axially aligned. The first and second eccentric portions 54A, 54B are eccentric to each other.
The crankshaft 5 configured as described above is arranged inside the outer cylinder 2 together with the carrier 3 . Although not shown, a plurality of (for example, three) crankshafts 5 are arranged at intervals in the circumferential direction of the carrier 3 .

The crank bearing 7 is arranged on inner peripheral surfaces 31 e and 32 e of the insertion holes 31 b and 32 b of the carrier 3 . Specifically, the crank bearing 7 (hereinafter referred to as the first crank bearing 71 ) is arranged between the radial support portion 31 h of the insertion hole 31 b of the first member 31 and the first journal portion 51 . The crank bearing 7 (hereinafter referred to as the second crank bearing 72 ) is arranged between the radial support portion 32 h of the insertion hole 32 b of the second member 32 and the second journal portion 52 . Crank bearing 7 allows rotation of crankshaft 5 with respect to carrier 3 .

As shown in FIG. 2, the first crank bearing 71 includes a plurality of cylindrical rolling elements 71a arranged in a radial support portion 31h (inner peripheral surface 31e) of the insertion hole 31b, and a plurality of rolling elements 71a. It has a retainer 71b for holding.
The plurality of rolling elements 71a are arranged in the circumferential direction of the radial support portion 31h (inner peripheral surface 31e) of the insertion hole 31b. The plurality of rolling elements 71a are each formed in a columnar shape extending in the axial direction of the radial support portion 31h. That is, the first crank bearing 71 is a needle roller bearing in which the axial direction of the rolling element 71a is parallel to the axis of the radial support portion 31h. Therefore, the first crank bearing 71 can easily move relative to the carrier 3 in the axial direction of the insertion hole 31b.

The retainer 71b includes an annular portion 71c disposed along the inner peripheral surface of the radial support portion 31h (inner peripheral surface 31e) of the insertion hole 31b, and flanges protruding radially from both axial ends of the annular portion 71c. 71d.
The annular portion 71c is formed with a pocket 71e that radially penetrates the annular portion 71c. A plurality of pockets 71e are arranged at intervals in the circumferential direction of the annular portion 71c. Each of the plurality of pockets 71e accommodates one rolling element 71a. A portion of each rolling element 71a enters the pocket 71e from the radially inner side of the annular portion 71c. The rest of each rolling element 71a protrudes radially inward from the annular portion 71c.

The flange portion 71d is positioned on both sides of the rolling element 71a in the axial direction of the annular portion 71c. The flange portion 71d protrudes radially inward from both ends of the annular portion 71c. The flange portion 71d is formed over the entire circumference of the annular portion 71c. Thereby, the flange portion 71d covers the rolling element 71a from the axial direction.
The flange portion 71d includes a first flange portion 71d1 arranged on the side of the outer end portion 31d of the first member 31 in the axial direction, and a second flange portion 71d2 arranged on the side of the inner end portion 31c of the first member 31. There is A radial length D1 of the first flange portion 71d1 radially extending from the annular portion 71c is smaller than a radial length D2 of the second flange portion 71d2. Therefore, the area of the rolling element 71a covered by the first flange 71d1 is smaller than the area of the rolling element 71a covered by the second flange 71d2.

Although not shown, the configuration of the second crank bearing 72 (see FIG. 1) attached to the insertion hole 32b of the second member 32 is the same as that of the first crank bearing 71 described above. That is, the second crank bearing 72 has, like the first crank bearing 71, a plurality of rolling elements 72a and a cage that holds them. The retainer also has an annular portion similar to the first crank bearing 71, and a first flange portion and a second flange portion provided at both ends in the axial direction.

As shown in FIG. 1 , the oscillating gear 4 is arranged inside the outer cylinder 2 like the carrier 3 . Also, the oscillating gear 4 is arranged between the first and second members 31 and 32 of the carrier 3 in the direction of the axis C1. The oscillating gear 4 is attached to the eccentric portion 54 of the crankshaft 5 via the eccentric portion bearing 8 . The oscillating gear 4 oscillates and rotates inside the outer cylinder 2 as the crankshaft 5 rotates.

The oscillating gear 4 of this embodiment has a first oscillating gear 41 attached to the first eccentric portion 54A of the crankshaft 5 and a second oscillating gear 42 attached to the second eccentric portion 54B. The first and second oscillating gears 41 and 42 are arranged in the direction of the axis C1.
The first oscillating gear 41 is formed with a first insertion hole 41a penetrating in the direction of the axis C1 and into which the first eccentric portion 54A is inserted. The speed reducer 1 includes a first eccentric portion bearing 81 provided between the outer circumference of the first eccentric portion 54A and the inner circumference of the first insertion hole 41a. The first eccentric part bearing 81 allows the rotation of the first eccentric part 54A with respect to the first oscillating gear 41 .

The second oscillating gear 42 is formed with a second insertion hole 42a penetrating in the direction of the axis C1 and into which the second eccentric portion 54B is inserted. The speed reducer 1 includes a second eccentric portion bearing 82 provided between the outer circumference of the second eccentric portion 54B and the inner circumference of the second insertion hole 42a. The second eccentric part bearing 82 allows rotation of the second eccentric part 54B with respect to the second oscillating gear 42 .

The first and second eccentric bearings 81 and 82 are roller bearings similar to the crank bearing 7 . That is, the first and second eccentric portion bearings 81 and 82 have a plurality of cylindrical rolling elements arranged in the circumferential direction. The axial direction of the rolling elements is parallel to the axis of the crankshaft 5 . For this reason, the first and second eccentric portion bearings 81 and 82, like the crank bearing 7, are arranged in axial directions of the first and second insertion holes 41a and 42a with respect to the first and second oscillating gears 41 and 42, respectively. can move to The crankshaft 5 can also move axially with respect to the carrier 3 and the first and second oscillating gears 41 and 42 .

The first and second oscillating gears 41 and 42 each have a plurality of external teeth 41b and 42b on their outer peripheries. The plurality of external teeth 41b, 42b are arranged in the circumferential direction. The external teeth 41b, 42b of the first and second oscillating gears 41, 42 mesh with the internal teeth 21 of the outer cylinder 2 described above. The circumferential length of the outer circumferences of the first and second oscillating gears 41 and 42 is smaller than the circumferential length of the inner circumference of the outer cylinder 2 . The number of external teeth 41b, 42b of the first and second oscillating gears 41, 42 is smaller than the number of internal teeth 21 of the outer cylinder 2.
The first and second rocking gears 41 and 42 have central holes 41c and 42c corresponding to the positions of the central holes 31a and 32a of the carrier 3, and through holes 41d and 42d through which the shaft portion 33 of the carrier 3 passes. is also formed.

The speed reducer 1 of this embodiment further includes a transmission gear 9 that transmits driving force to the crankshaft 5 to rotate the crankshaft 5 . The mounting position of the transmission gear 9 with respect to the crankshaft 5 may be arbitrary. In this embodiment, the transmission gear 9 is attached to the small diameter portion 53 of the crankshaft 5 located outside the carrier 3 in the direction of the axis C1. The transmission gear 9 rotates around the axis of the small diameter portion 53 . The transmission gear 9 has a plurality of external teeth 91 on its outer periphery. The transmission gear 9 transmits the driving force of the motor to the crankshaft 5 by meshing the external teeth 91 of the transmission gear 9 with an input shaft (not shown) of the motor.

In the speed reducer 1 of this embodiment configured as described above, when the crankshaft 5 rotates by receiving the driving force from the transmission gear 9, the eccentric rotation of the first and second eccentric portions 54A and 54B causes the first and second The first and second oscillating gears 41 and 42 are mounted on the outer cylinder so that the meshing positions of the external teeth 41b and 42b of the second oscillating gears 41 and 42 and the internal teeth 21 of the outer cylinder 2 move in the circumferential direction. 2 to swing and rotate.

In addition, since the first eccentric portion 54A and the second eccentric portion 54B are eccentric to each other, the external teeth 41b of the first oscillating gear 41 and the external teeth 42b of the second oscillating gear 42 are arranged in the circumferential direction. It meshes with the internal teeth 21 of the outer cylinder 2 at different positions. As a result, the first oscillating gear 41 and the second oscillating gear 42 oscillate and rotate inside the outer cylinder 2 in phases different from each other.

The oscillating rotation of the first and second oscillating gears 41 and 42 is transmitted to the carrier 3 via the crankshaft 5, so that the carrier 3 rotates with respect to the outer cylinder 2 about the axis C1. That is, the outer cylinder 2 and the carrier 3 rotate relatively. This relative rotational speed is slower than the rotational speed of the crankshaft 5 . That is, the rotation of the carrier 3 or the outer cylinder 2, which is reduced with respect to the input rotation of the crankshaft 5, can be output.

As shown in FIG. 1 , the regulating member 6 is attached next to the crank bearing 7 in the axial direction among the inner peripheral surfaces 31 e and 32 e of the insertion holes 31 b and 32 b of the carrier 3 . The regulating member 6 of this embodiment has male threaded portions 61a and 62a that mesh with the female threaded portions 31f and 32f of the insertion holes 31b and 32b. That is, the restricting member 6 is attached to the insertion holes 31b and 32b of the carrier 3 by meshing the male threaded portions 61a and 62a with the female threaded portions 31f and 32f of the carrier 3 .
When the restricting member 6 is attached to the carrier 3, the restricting member 6 faces the crank bearing 7 in the axial direction. The restricting member 6 restricts axial movement of the crank bearing 7 by contacting the rolling elements 71 a and 72 a of the crank bearing 7 . In addition, since the restricting member 6 also faces the crankshaft 5 in the axial direction, it also restricts the movement of the crankshaft 5 in the axial direction.

The regulating member 6 has a first regulating member 61 and a second regulating member 62 arranged adjacent to each other in the axial direction of the crankshaft 5 excluding the small diameter portion 53 . The first restricting member 61 and the second restricting member 62 sandwich the crankshaft 5 from the axial direction. Thereby, the first restricting member 61 and the second restricting member 62 can restrict the movement of the crankshaft 5 in the axial direction.

The first restricting member 61 is formed in a circular shape when viewed from the axial direction of the crankshaft 5 . As shown in FIGS. 1 and 2 , the first restricting member 61 is attached to the first member 31 of the carrier 3 and axially adjacent to the first crank bearing 71 and the first journal portion 51 . For this reason, the first restricting member 61 is formed with a through hole 61c through which the small diameter portion 53 of the crankshaft 5 passes through in the axial direction.
The outer peripheral portion of the first restricting member 61 in the radial direction contacts the stepped portion 31g of the insertion hole 31b of the first member 31 . Thereby, the first restricting member 61 is positioned with respect to the first member 31 in the axial direction.

In this state, as shown in FIG. 2, the first collar portion 71d1 of the first crank bearing 71 is arranged between the first restricting member 61 and the rolling element 71a in the axial direction. Further, the second flange portion 71d2 of the first crank bearing 71 is arranged so as to position the rolling element 71a between the first flange portion 71d1 and the first flange portion 71d1 in the axial direction.

As shown in FIGS. 2 and 3, the first restricting member 61 includes a main body portion 61d attached to the insertion hole 31b (inner peripheral surface 31e) of the first member 31 and a contact protrusion 61e protruding from the main body portion 61d. have.
The contact convex portion 61e protrudes from a facing surface 61f of the main body portion 61d facing the first brim portion 71d1 of the first crank bearing 71 in the axial direction. The contact convex portion 61e is located radially inward of the first collar portion 71d1. As a result, the contact protrusion 61 e can come into contact with the rolling element 71 a of the first crank bearing 71 . A protruding length L1 of the contact protrusion 61e in the axial direction is greater than the thickness T1 of the first collar portion 71d1 in the axial direction. As a result, even if the contact convex portion 61e of the first restricting member 61 contacts the rolling element 71a of the first crank bearing 71, the body portion 61d of the first restricting member 61 does not contact the rolling element 71a.

Further, the contact protrusion 61e of the present embodiment also protrudes from the surface 61g of the body portion 61d facing the first journal portion 51 of the crankshaft 5 in the axial direction. 2 and 3, the surface 61g of the body portion 61d facing the first journal portion 51 is positioned closer to the first journal portion 51 than the facing surface 61f of the body portion 61d in the axial direction. There is no limit. Further, the contact convex portion 61e does not have to protrude from the surface 61g of the main body portion 61d facing the first journal portion 51, for example.
Further, the contact convex portion 61e of the present embodiment is formed over the entire circumferential direction of the first restricting member 61. As shown in FIG. As a result, the contact protrusions 61e come into contact with the plurality of rolling elements 71a of the first crank bearing 71 arranged in the circumferential direction. A plurality of contact protrusions 61e may be arranged in the circumferential direction of the first restricting member 61, for example.

The surface of the first regulating member 61 that contacts the rolling elements 71a of the first crank bearing 71, that is, the surface of the contact protrusion 61e preferably has an arithmetic mean roughness Ra of, for example, 0.8 μm or less. Further, it is preferable that the hardness of the contact protrusion 61e is equal to or higher than the hardness of the rolling elements 71a of the first crank bearing 71 (for example, 58 HRC or higher). In order to reduce the surface roughness of the contact protrusions 61e and improve the hardness of the contact protrusions 61e, the first regulating member 61 (especially the contact protrusions 61e) may be subjected to polishing treatment, heat treatment, or the like. . Abrasion of the contact protrusions 61e that contact the rolling elements 71a can be suppressed by making the contact protrusions 61e have a low surface roughness or a high hardness.

The first restricting member 61 of the present embodiment has a housing recess 61h that houses the first flange 71d1 of the first crank bearing 71. As shown in FIG. The accommodation recess 61h is recessed from the end surface 61i of the first regulating member 61 facing the first crank bearing 71 in the axial direction. The accommodating concave portion 61h is formed by a step between the facing surface 61f of the main body portion 61d and the end surface 61i of the first restricting member 61 forming the contact convex portion 61e.

Although not shown, the configuration of the second restricting member 62 (see FIG. 1) attached to the insertion hole 32b of the second member 32 is the same as that of the first restricting member 61 described above. That is, like the first restricting member 61 , the second restricting member 62 has a main body and a contact protrusion 62 e that protrudes from the main body and contacts the rolling element 72 a of the second crank bearing 72 . In addition, the second restricting member 62 has a housing recess that houses the first flange of the second crank bearing 72 .
A member common to the first restricting member 61 is used for the second restricting member 62 of the present embodiment. For this reason, the second restricting member 62 is also formed with a through hole 62c penetrating it in the axial direction, but it is not limited to this.

Thus, in the bearing mechanism 100 and the speed reducer 1 described above, the restricting member 6 that restricts the axial movement of the crank bearing 7 contacts the rolling elements 71 a and 72 a of the crank bearing 7 . Therefore, when the crank bearing 7 is pressed against the regulating member 6 in the axial direction, at least the regulating member 6 comes into contact with the rolling elements 71a and 72a. Therefore, compared to the case where the restricting member 6 contacts only the retainer 71 b of the crank bearing 7 , the load acting on the retainer 71 b due to the pressing of the crank bearing 7 against the restricting member 6 can be reduced. Therefore, the concentration of the load on the retainer 71b of the crank bearing 7 can be alleviated to protect the retainer 71b. Moreover, since the crank bearing 7 can be protected, the reliability of the bearing mechanism 100 and the reduction gear 1 can be improved.
The above effect is particularly effective when the crank bearing 7 is a needle roller bearing that can easily move relative to the carrier 3 in the axial direction of the insertion hole 31b.

The restricting member 6 includes a main body portion 61d attached to the insertion holes 31b and 32b (inner peripheral surfaces 31e and 32e) of the carrier 3, and a contact member protruding from the main body portion 61d and contacting the rolling elements 71a and 72a of the crank bearing 7. It has projections 61e and 62e. The length of protrusion of the contact protrusions 61e and 62e in the axial direction is greater than the thickness of the collar portion 71d of the retainer 71b in the axial direction. Therefore, even if the contact protrusions 61e and 62e of the regulating member 6 come into contact with the rolling elements 71a and 72a, the retainer disposed between the main body 61d of the regulating member 6 and the rolling elements 71a and 72a in the axial direction will not be held. The contact of the first flange portion 71d1 of the 71b with the body portion 61d of the restricting member 6 can be suppressed or prevented. Therefore, the retainer 71b can be protected more reliably.

Further, the regulating member 6 has an accommodation recess 61h which is recessed from an end surface 61i facing the crank bearing 7 in the axial direction and accommodates the first flange 71d1 of the retainer 71b. Therefore, in a state in which the first collar portion 71d1 of the retainer 71b arranged between the regulating member 6 and the rolling elements 71a and 72a in the axial direction is accommodated in the accommodating recess 61h of the regulating member 6, the end surface of the regulating member 6 is 61i can be brought into contact with the rolling elements 71a, 72a of the crank bearing 7; Thereby, even if the restricting member 6 comes into contact with the crank bearing 7 in the axial direction, the contact of the first flange portion 71d1 of the retainer 71b with the restricting member 6 can be suppressed or prevented. Therefore, the retainer 71b can be protected more reliably.

In addition, among the flanges 71d located on both sides of the rolling elements 71a and 72a in the crank bearing 7, the radial direction of the first flange 71d1 arranged between the regulating member 6 and the rolling elements 71a and 72a in the axial direction. The length D1 is smaller than the radial length D2 of the second flange portion 71d2 that positions the rolling elements 71a and 72a between the first flange portion 71d1 and the first flange portion 71d1. Therefore, the area of the rolling elements 71a and 72a covered by the first collar portion 71d1 in the axial direction is reduced. That is, the areas of the rolling elements 71a and 72a facing the restricting member 6 without interposing the first flange portion 71d1 in the axial direction are increased. As a result, the areas of the rolling elements 71a and 72a that come into contact with the restricting member 6 can be secured, and the contact protrusions 61e and 62e (or the end surface 61i) of the restricting member 6 can be stably brought into contact with the rolling elements 71a and 72a. .

In the first crank bearing 71 of the first embodiment, for example, part of each rolling element 71a enters the pocket 71e from the radially outer side of the annular portion 71c of the retainer 71b, and the remaining portion of each rolling element 71a extends from the annular portion 71c. It may protrude radially outward. In this case, the flange portions 71d of the retainer 71b may, for example, protrude radially outward from both axial ends of the annular portion 71c. The second crank bearing 72 may be configured in the same manner as the first crank bearing 71 described above, for example.

In the crank bearing 7 of the first embodiment, for example, the axial directions of the rolling elements 71a and 72a may be inclined with respect to the axis of the radial support portion 31h. That is, the crank bearing 7 may be, for example, a tapered roller bearing.

In the bearing mechanism and speed reducer of the first embodiment, the restricting member may not have a male threaded portion, and may be attached to the carrier by being fitted into the inner peripheral surface of the insertion hole of the carrier, for example.

[Second embodiment]
Next, a second embodiment of the present invention will be described mainly with reference to FIGS. 4 and 5, focusing on differences from the first embodiment. In addition, about the structure which is common in 1st embodiment, the same code|symbol is attached|subjected and the description is abbreviate|omitted.

As shown in FIG. 4, a reduction gear 1M according to this embodiment includes an outer cylinder 2 (see FIG. 1), a carrier 3, an oscillating gear 4, and a crankshaft (rotating shaft) 5 similar to those in the first embodiment. . Further, the speed reducer 1M of the present embodiment includes, as in the first embodiment, eccentric bearings (roller bearings) 8 interposed between the inner peripheral surfaces 41e and 42e of the oscillating gear 4 and the crankshaft 5, and a regulating member 10M attached to the crankshaft 5. Furthermore, the speed reducer 1M of this embodiment includes a crank bearing (small diameter bearing) 7M interposed between the inner peripheral surface 32e of the carrier 3 and the crankshaft 5, as in the first embodiment.
The crankshaft 5, the eccentric bearing 8, the regulating member 10M and the crank bearing 7M constitute a bearing mechanism 100M according to this embodiment. The bearing mechanism 100M is a mechanism that restricts axial movement of the eccentric bearing 8 by means of a restricting member 10M.

In this embodiment, the inner peripheral surface 32e of the insertion hole 32b of the second member 32 into which the crankshaft 5 of the carrier 3 is inserted is replaced with the female threaded portion 32f (see FIG. 1) as in the first embodiment. It has an annular recess 32j recessed from the inner peripheral surface 32e and extending in the circumferential direction. A ring-shaped retaining ring 6M that restricts axial movement of the crank bearing 7M arranged on the inner peripheral surface 32e of the second member 32 is fitted in the annular recess 32j.
Although not shown, the insertion hole 31b (see FIG. 1) of the first member 31 of the carrier 3 may be configured similarly to the insertion hole 32b of the second member 32 described above. That is, a retaining ring may be fitted in the insertion hole 31b of the first member 31 instead of the restricting member 6 (see FIG. 1) of the first embodiment.

A crank bearing 7M arranged on the inner peripheral surface 32e of the second member 32 allows rotation of the crankshaft 5 with respect to the carrier 3 as in the first embodiment. The crank bearing 7M of the present embodiment includes a plurality of cylindrical rolling elements 7Ma arranged in the circumferential direction of the inner peripheral surface 32e, a retainer 7Mb that holds the plurality of rolling elements 7Ma, and a diameter of the plurality of rolling elements 7Ma. An annular inner ring 7Mc arranged on the inner side in the direction and an annular outer ring 7Md arranged on the outer side in the radial direction with respect to the plurality of rolling elements 7Ma are provided. The crank bearing 7M may be, for example, a needle roller bearing in which the axial direction of the rolling element 7Ma is parallel to the axis C2 of the inner peripheral surface 32e of the second member 32, but in the present embodiment, the axial direction of the rolling element 7Ma is a tapered roller bearing inclined with respect to the axis C2 of the inner peripheral surface 32e.

The crankshaft 5 has a second journal portion (small diameter shaft portion) 52 and a second eccentric portion (large diameter shaft portion) 54B located next to the second journal portion 52, as in the first embodiment. The diameter dimension of the second journal portion 52 is smaller than the diameter dimension of the second eccentric portion 54B. The axis C2 of the second journal portion 52 and the axis C3 of the second eccentric portion 54B are parallel but offset from each other. The outer circumference of the second journal portion 52 is located radially inside the outer circumference of the second eccentric portion 54B. The above-described crank bearing 7M is arranged on the outer circumference of the second journal portion 52 . A second eccentric part bearing 82 (eccentric part bearing 8) is attached to the outer peripheral surface of the second eccentric part 54B.
Although not shown, the relationship between the first journal portion 51 and the first eccentric portion 54A that constitute the crankshaft 5 is the same as the relationship between the second journal portion 52 and the second eccentric portion 54B described above (Figs. 2).

The second eccentric portion bearing 82 has a plurality of cylindrical rolling elements 82a arranged on the outer peripheral surface of the second eccentric portion 54B, and a retainer 82b that holds the plurality of rolling elements 82a.
A plurality of rolling elements 82a are arranged in the circumferential direction of the outer peripheral surface of the second eccentric portion 54B. The plurality of rolling elements 82a are each formed in a columnar shape extending in the axial direction of the second eccentric portion 54B. That is, the second eccentric portion bearing 82 is a needle roller bearing in which the axial direction of the rolling element 82a is parallel to the axis C3 of the second eccentric portion 54B. Therefore, the second eccentric portion bearing 82 can easily move in the axial direction with respect to the second eccentric portion 54B.

The retainer 82b has an annular portion 82c arranged along the outer peripheral surface of the second eccentric portion 54B, and flange portions 82d radially protruding from both axial ends of the annular portion 82c.
The annular portion 82c has a plurality of pockets 82e radially penetrating the annular portion 82c and arranged in the circumferential direction of the annular portion 82c. Each of the plurality of pockets 82e accommodates one rolling element 82a. A portion of each rolling element 82a enters the pocket 82e from the radially inner side of the annular portion 82c. The rest of each rolling element 82a protrudes radially inward from the annular portion 82c.

The flange portion 82d is positioned on both sides of the rolling element 82a in the axial direction of the annular portion 82c. The collar portions 82d protrude radially inward from both ends of the annular portion 82c. As shown in FIG. 5, the collar portion 82d is formed over the entire circumference of the annular portion 82c. That is, the collar portion 82d is formed in an annular shape (annular shape) when viewed from the axial direction. The flange portion 82d covers the rolling element 82a from the axial direction. However, a portion of each rolling element 82a protrudes radially inward from the inner edge 82f of the flange portion 82d.

As shown in FIG. 4, the structure of the first eccentric part bearing 81 attached to the outer peripheral surface of the first eccentric part 54A is the same as that of the second eccentric part bearing 82 described above. That is, the first eccentric portion bearing 81 has a plurality of rolling elements and a cage that holds them. Further, the retainer has an annular portion and flange portions provided at both axial ends thereof.

As shown in FIGS. 4 and 5, the restricting member 10M is formed in an annular shape through which the crankshaft 5 is passed. The regulating member 10M is attached next to the eccentric portion bearing 8 in the axial direction on the outer peripheral surface of the crankshaft 5 . The regulating member 10M faces and contacts the rolling elements 82a of the eccentric bearing 8 in the axial direction.
In this embodiment, the restricting member 10M is formed in an annular shape when viewed from the axial direction. The restricting member 10M passes through the second journal portion 52 of the crankshaft 5 and is arranged next to the second eccentric portion 54B to which the second eccentric portion bearing 82 is attached.

The inner diameter dimension of the restricting member 10</b>M should be at least smaller than the diameter dimension of the second eccentric portion 54</b>B and larger than the diameter dimension of the second journal portion 52 . As a result, the restricting member 10M is arranged to overlap the second eccentric portion 54B from the second journal portion 52 side in the axial direction. Further, the restricting member 10M is sandwiched and fixed in the axial direction between the second eccentric portion 54B and the crank bearing 7M. Specifically, the restricting member 10M is fixed by being sandwiched between the second eccentric portion 54B and the inner ring 7Mc of the crank bearing 7M in the axial direction.
It is more preferable that the difference between the inner diameter dimension of the regulating member 10M and the diameter dimension of the second journal portion 52 is small. In this case, it is possible to suppress or prevent displacement of the restricting member 10M in the direction orthogonal to the axial direction with respect to the second journal portion 52 and the second eccentric portion 54B.

The outside diameter dimension of the regulation member 10M is larger than the diameter dimension of the second eccentric portion 54B. Therefore, the outer peripheral portion of the regulating member 10M protrudes radially outside the second eccentric portion 54B. The outer peripheral portion of the regulating member 10M faces and contacts the rolling elements 82a of the second eccentric portion bearing 82 in the axial direction. Thereby, the restricting member 10M restricts the axial movement of the second eccentric portion bearing 82 with respect to the crankshaft 5 .

The outer peripheral edge 10Ma of the regulating member 10M is eccentric with respect to the inner peripheral edge 10Mb. Therefore, the center of the inner peripheral edge 10Mb of the restricting member 10M can be aligned with the axis C2 of the second journal portion 52 when the second journal portion 52 is passed through the restricting member 10M. Further, the center of the outer peripheral edge 10Ma of the regulating member 10M can be aligned with the axis C3 of the second eccentric portion 54B. In addition, the outer peripheral portion of the restricting member 10M can be projected outside the second eccentric portion 54B over the entire circumference of the second eccentric portion 54B.

As shown in FIG. 4, the regulating member 10M (especially the outer peripheral portion) is positioned between the two flange portions 82d of the second eccentric portion bearing 82 and one flange portion 82d1 located on the first eccentric portion 54A side in the axial direction. It is arranged so that the rolling element 82a is positioned between them. A distance D3 between the regulating member 10M and one flange 82d1 in the axial direction is smaller than a distance D4 between the two flanges 82d.

As shown in FIGS. 4 and 5, the outer diameter of the regulating member 10M is the same as the regulating member 10M of the two flanges 82d of the second eccentric bearing 82. The other flange 82d2 located on the second journal 52 side is smaller than the inner diameter of Therefore, a gap S1 is formed between the outer peripheral edge 10Ma of the restricting member 10M and the inner edge 82f of the other flange 82d2 when viewed in the axial direction. The gap S1 is formed in an annular shape when viewed from the axial direction. The outer peripheral edge 10Ma of the regulating member 10M and the inner edge 82f of the other flange 82d2 may, for example, be offset from each other in the axial direction, but in this embodiment, they face each other in the radial direction.

As shown in FIG. 4, the regulating member 10M of the present embodiment includes an annular main body portion 10Mc through which the second journal portion 52 is passed, and from the outer peripheral portion of the main body portion 10Mc in the axial direction toward the second eccentric portion bearing 82. It has a contact convex portion 10Md that protrudes and contacts the rolling element 82a. In this embodiment, the main body portion 10Mc and the contact convex portion 10Md are integrally formed.
The body portion 10Mc is axially sandwiched between the second eccentric portion 54B and the crank bearing 7M. The outer peripheral portion of the body portion 10Mc is a portion of the body portion 10Mc that protrudes radially outward from the second eccentric portion 54B.

The contact convex portion 10Md of the present embodiment is formed over the entire circumferential direction of the main body portion 10Mc. As a result, the contact protrusion 10Md contacts the plurality of rolling elements 82a of the second eccentric bearing 82 arranged in the circumferential direction. A plurality of contact protrusions 10Md may be arranged in the circumferential direction of the main body 10Mc, for example.
Further, the contact convex portion 10Md is arranged so as to face the outer peripheral surface of the second eccentric portion 54B in the radial direction. Therefore, the inner diameter of the contact protrusion 10Md should be at least larger than the diameter of the second eccentric portion 54B. It is more preferable that the difference between the inner diameter dimension of the contact protrusion 10Md and the diameter dimension of the second eccentric portion 54B is small.

It is preferable that the hardness of the regulating member (especially the contact convex portion) contacting the rolling elements of the second eccentric bearing is equal to or higher than the hardness of the rolling elements of the second eccentric bearing (for example, 58 HRC or higher). Further, the arithmetic mean roughness Ra of the surface of the regulating member (especially the contact convex portion) that contacts the rolling elements of the second eccentric bearing is preferably 0.8 μm or less, for example. In order to improve the hardness of the regulating member and reduce the surface roughness of the regulating member, the regulating member (especially the contact convex portion) may be subjected to heat treatment, polishing, or the like. When the hardness of the regulating member is high or the surface roughness of the regulating member is low, it is possible to suppress wear of the regulating member (especially the contact protrusion) that contacts the rolling element.

Although not shown, the regulating member 10M is arranged next to the first eccentric portion 54A to which the first eccentric portion bearing 81 is attached after passing through the first journal portion 51 (see FIG. 1) of the crankshaft 5. be. That is, the restricting member 10M is arranged on both sides of the first and second eccentric portions 54A and 54B so as to sandwich the first and second eccentric portions 54A and 54B in the axial direction.
The configuration of the regulating member 10M arranged next to the first eccentric portion 54A may be the same as that of the aforementioned regulating member 10M arranged next to the second eccentric portion 54B.

The bearing mechanism 100M and the speed reducer 1M of the second embodiment have the same effects as those of the first embodiment. That is, the restricting member 10</b>M that restricts the movement of the eccentric bearing 8 in the axial direction contacts the rolling elements 82 a of the eccentric bearing 8 . Therefore, when the eccentric portion bearing 8 is axially pressed against the regulating member 10M, at least the regulating member 10M contacts the rolling elements 82a. Therefore, compared to the case where the restricting member 10M contacts only the retainer 82b of the eccentric bearing 8, the load acting on the retainer 82b as the eccentric bearing 8 presses against the restricting member 10M can be reduced. Therefore, concentration of the load on the retainer 82b of the eccentric bearing 8 can be alleviated to protect the retainer 82b. Moreover, since the eccentric portion bearing 8 can be protected, the reliability of the bearing mechanism 100M and the speed reducer 1M can be improved.
The above effects are particularly effective when the eccentric portion bearing 8 is a needle roller bearing that can easily move in the axial direction with respect to the crankshaft 5 (eccentric portion 54).

A gap S1 is formed between the outer peripheral edge 10Ma of the regulating member 10M and the inner edge 82f of the other flange 82d2 of the eccentric bearing 8 when viewed in the axial direction. Therefore, a lubricant (for example, lubricating oil) passes through the gap S1 between the regulating member 10M and the other flange portion 82d2, between the rolling element 82a and the regulating member 10M that are in contact with each other, and on the sliding surface of the rolling element 82a ( It becomes easier to reach the surface of the rolling element 82a that contacts the outer circumference of the crankshaft 5 and the inner circumference of the oscillating gear. As a result, the wear of the rolling elements 82a and the restricting member 10M that are in contact with each other can be suppressed. Therefore, the service life of the bearing mechanism 100M can be extended.

Also, the distance D3 between the regulating member 10M (especially the contact protrusion 10Md) and one flange 82d1 of the eccentric bearing 8 is smaller than the distance D4 between the flanges 82d of the eccentric bearing 8 in the axial direction. Therefore, the moving length of the rolling element 82a in the axial direction can be further reduced by the restricting member 10M. Thereby, the inclination of the rolling element 82a with respect to the axial direction can be kept small. Therefore, the sliding resistance of the rolling elements 82a with respect to the crankshaft 5 (eccentric portion 54) can be reduced, and the skew force (torsion force) acting on the crankshaft 5 can be reduced.

Further, the regulating member 10M (especially the main body portion 10Mc) is sandwiched and fixed between the eccentric portion 54 of the crankshaft 5 and the crank bearing 7M arranged on the outer periphery of the journal portion 52 in the axial direction. Therefore, it is possible to suppress or prevent axial movement of the regulating member 10M with respect to the crankshaft 5 . As a result, axial movement of the eccentric portion bearing 8 with respect to the crankshaft 5 can be effectively restricted by the restricting member 10M.

In the regulating member 10M of the second embodiment, the main body portion 10Mc and the contact convex portion 10Md may be formed separately, for example, and then fixed to each other by arbitrary means such as welding or countersunk screws. In this case, only the hardness and surface roughness of the contact protrusions 10</b>Md that contact the rolling elements of the eccentric bearing 8 should correspond to the rolling elements of the eccentric bearing 8 . That is, the hardness and surface roughness of the main body portion 10Mc may be different from those of the contact protrusions 10Md, for example.

The restricting member 10M of the second embodiment may be fixed to the crankshaft 5 by any means such as screwing.

Although the details of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

The number of oscillating gears in the speed reducer of the present invention may be, for example, one, or three or more. Also, the number of eccentric portions on the crankshaft should correspond to the number of oscillating gears.

The bearing mechanism according to the present invention is not limited to being applied to speed reducers, and may be applied to any machine or device.

DESCRIPTION OF SYMBOLS 1, 1M... Reduction gear, 2... Outer cylinder, 3... Carrier (base member), 4... Rocking gear, 5... Crank shaft (rotating shaft), 6... Regulating member, 7... Crank bearing (roller bearing), 7M ... Crank bearing (small-diameter bearing), 8 ... Eccentric portion bearing (roller bearing), 10M ... Regulating member, 10Ma ... Outer peripheral edge, 10Mc ... Body portion, 10Md ... Contact convex portion, 31 ... First member, 31e ... Inner peripheral surface , 31f... female screw portion, 31h... radial direction support portion, 32... second member, 32e... inner peripheral surface, 32f... female thread portion, 32h... radial direction support portion, 51... first journal portion (small diameter shaft portion), 52 ... second journal portion (small diameter shaft portion), 54 ... eccentric portion (large diameter shaft portion), 54A ... first eccentric portion (large diameter shaft portion), 54B ... second eccentric portion (large diameter shaft portion), 61 ... First restricting member 61a Male threaded portion 61d Body portion 61e Contact convex portion 61f Opposing surface 61h Accommodating recessed portion 61i End surface 62 Second restricting member 62a Male threaded portion 62e Contact Convex part 71... First crank bearing 71a... Rolling element 71b... Cage 71c... Annular part 71d... Flange part 71d1... First brim part 71d2... Second brim part 72... Second crank bearing , 72a Rolling element 81 First eccentric bearing 82 Second eccentric bearing 82a Rolling element 82b Cage 82c Annular portion 82d Flange 82d1 One flange 82d2 ... other collar portion, 82f ... inner edge, 100, 100M ... bearing mechanism

Claims (5)

a roller bearing having a plurality of cylindrical rolling elements and a retainer that holds the plurality of rolling elements;
a restricting member that restricts axial movement of the roller bearing by coming into contact with the rolling elements of the roller bearing;
a base member having an inner peripheral surface,
The plurality of rolling elements are arranged on the inner peripheral surface,
The rolling elements are formed in a cylindrical shape extending in the axial direction of the inner peripheral surface and arranged in the circumferential direction of the inner peripheral surface,
the regulating member is attached next to the roller bearing in the axial direction on the inner peripheral surface and contacts the rolling element in the axial direction;
The retainer has an annular portion arranged along the inner peripheral surface, and flange portions projecting radially from both axial ends of the annular portion and positioned on both sides of the rolling elements in the axial direction,
The regulating member has a body portion attached to the inner peripheral surface, and a contact convex portion that protrudes from the facing surface of the body portion facing the roller bearing in the axial direction and contacts the rolling element,
A bearing mechanism in which the protruding length of the contact protrusion in the axial direction is greater than the thickness of the flange in the axial direction . a roller bearing having a plurality of cylindrical rolling elements and a retainer that holds the plurality of rolling elements;
a restricting member that restricts axial movement of the roller bearing by coming into contact with the rolling elements of the roller bearing;
a base member having an inner peripheral surface,
The plurality of rolling elements are arranged on the inner peripheral surface,
The rolling elements are formed in a cylindrical shape extending in the axial direction of the inner peripheral surface and arranged in the circumferential direction of the inner peripheral surface,
the regulating member is attached next to the roller bearing in the axial direction on the inner peripheral surface and contacts the rolling element in the axial direction;
The retainer has an annular portion arranged along the inner peripheral surface, and flange portions projecting radially from both axial ends of the annular portion and positioned on both sides of the rolling elements in the axial direction,
The bearing mechanism, wherein the regulating member has an accommodation recess that is recessed from an end face facing the roller bearing in the axial direction and accommodates the flange . The retainer has an annular portion arranged along the inner peripheral surface, and flange portions projecting radially from both axial ends of the annular portion and positioned on both sides of the rolling elements in the axial direction,
The radial length of the first flange portion arranged between the regulating member and the rolling element in the axial direction of the flange portion is the distance between the first flange portion in the axial direction of the flange portion. 3. The bearing mechanism according to claim 1, wherein the length in the radial direction of the second collar portion at which the rolling element is positioned is smaller than the radial length of the second collar portion . a base member having an inner peripheral surface;
a plurality of rolling elements formed in a cylindrical shape extending in the axial direction of the inner peripheral surface and arranged in the circumferential direction of the inner peripheral surface; an annular portion arranged along the inner peripheral surface; a retainer that retains a plurality of the rolling elements including flanges that protrude radially from both axial ends of an annular portion and are located on both sides of the rolling elements in the axial direction; Among them, the radial length of the first flange portion is smaller than the radial length of the second flange portion that positions the rolling elements between the first flange portion and the first flange portion in the axial direction. and,
a body portion attached next to the roller bearing in the axial direction on the inner peripheral surface so that the first flange portion is positioned between the rolling elements in the axial direction; The contact protrusion protrudes from the facing surface of the main body portion to contact the rolling element, and has a contact convex portion whose length in the axial direction is larger than the thickness of the flange portion in the axial direction. a restricting member that restricts axial movement of the roller bearing;
bearing mechanism. a bearing mechanism according to any one of claims 1 to 4 ;
a rotating shaft rotatably supported on the inner peripheral surface via the roller bearing;
an outer cylinder in which the base member is arranged so as to be relatively rotatable;
an oscillating gear arranged inside the outer cylinder and oscillatingly rotating with the rotation of the rotating shaft;
The rotation shaft is a crankshaft that rotates the outer cylinder and the base member relative to each other at a speed slower than the rotation speed of the rotation shaft based on the oscillating rotation of the oscillating gear.

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