Rotary apparatus

Abstract

To provide a rotary apparatus that can prevent scattering of lubricant.SOLUTION: A rotary apparatus 1 comprises: gears 50, 51; a motor 4 that faces the gears 50, 51 in a rotation axis direction; a housing 2 that accommodates the gears 50, 51 and the motor 4; and a plate 28 that is directly or indirectly fixed to the housing 2. The plate 28 crosses the gears 50, 51 and the motor 4 arranged side by side in the rotation axis direction.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a rotating device.

Background Art

[0002] Patent Document 1 discloses a speed reducer. In this speed reducer, a concave portion is provided so as to accumulate a lubricant.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, in a rotating device having a motor and a speed reducer, it is desirable to prevent the lubricant covering the gear from scattering to the motor side.

[0005] Therefore, one of the problems of the present invention is to provide a rotating device capable of suppressing the scattering of the lubricant.

Means for Solving the Problems

[0006] The rotating device according to one aspect of the present invention includes a gear, a motor facing the gear in the rotational axis direction, a housing that houses the gear and the motor, and a plate directly or indirectly fixed to the housing, and the plate crosses between the gear and the motor arranged in the rotational axis direction.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view schematically showing the structure of a rotating device 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the 2-2 line of FIG. 1. FIG. 2 is a cross-section along a virtual plane including the rotation axis x. This rotating device 1 is a rotating device having a motor and a speed reducer for reducing the rotation of the motor, and is incorporated in, for example, an electric assist bicycle. The rotating device 1 includes a housing 2. The housing 2 generally has a substantially cylindrical shape as a whole, for example. The housing 2 is fixed to the frame of a bicycle, for example. Note that the bicycle includes all types of bicycles such as road bicycles, cross bicycles, mountain bicycles, and city bicycles.

[0009] A crankshaft 3 is rotatably supported in a housing 2 about a rotation axis x. In this example, the rotation axis x coincides with the central axis of the housing 2. The crankshaft 3 has one end 3a on one side S1 in a direction along the rotation axis x (hereinafter referred to as the "rotation axis direction"), and the other end 3b on the other side S2 opposite to the one side S1. Both the one end 3a and the other end 3b protrude from the housing 2 in the rotation axis direction. Crank arms (not shown) extending in a direction orthogonal to the rotation axis x are attached to the one end 3a and the other end 3b, respectively. A pedal (not shown) is attached to the tip of the crank arm. A chain ring (not shown) is further attached to the crank arm attached to the one end 3a.

[0010] The housing 2 has a housing (hereinafter referred to as a "motor housing") 20 that houses a motor 4, a housing (hereinafter referred to as a "gear housing") 21 that houses a speed reducer 5 according to an embodiment of the present invention, and a cover (hereinafter referred to as a "gear cover") 22. The motor housing 20, the gear housing 21, and the gear cover 22 are coupled to each other by fastening components 23 such as bolts extending in the rotation axis direction, for example. An annular member (hereinafter referred to as a "gasket") 24 seals between the motor housing 20 and the gear housing 21. An annular member (hereinafter referred to as a "gasket") 25 seals between the gear housing 21 and the gear cover 22. The housing 2 is formed of, for example, a metal material or a resin material. From the viewpoint of thermal conductivity, it is preferable that the motor housing 20 and the gear housing 21 are formed of a metal material. The gaskets 24 and 25 are formed of a metal material or a resin material having elasticity or resilience.

[0011] The motor housing 20 has a cylindrical outer portion (hereinafter referred to as the "outer peripheral portion") 20a centered on the rotation axis x, a cylindrical inner portion (hereinafter referred to as the "inner peripheral portion") 20b centered on the rotation axis x, and a wall 20c connecting the outer peripheral portion 20a and the inner peripheral portion 20b. In this example, the wall 20c connects the ends on the other side S2 of the outer peripheral portion 20a and the inner peripheral portion 20b. The outer peripheral portion 20a surrounds the motor 4 from the outer peripheral side in the radial direction orthogonal to the rotation axis x. The inner peripheral portion 20b is arranged inside the motor 4. The inner peripheral surface of the inner peripheral portion 20b faces the outer peripheral surface of the crankshaft 3. The wall 20c extends along a virtual plane orthogonal to the rotation axis x in this example. That is, the wall 20c faces the motor 4 in the rotation axis direction and forms a bottom.

[0012] A bearing 10 is arranged between the inner peripheral side end of the wall 20c and the outer peripheral surface of the crankshaft 3. The bearing 10 is a bearing having rolling elements, for example, a ball bearing. In this way, the motor housing 20 supports the crankshaft 3 so as to be relatively rotatable via the bearing 10 at the inner peripheral side end of the wall 20c. The housing 2 further has an annular end cover 26. The end cover 26 covers the other end side S2 of the bearing 10 along the rotation axis direction. The end cover 26 is fixed to the wall 20c by fastening parts 27 such as screws, for example. The other end 3b of the crankshaft 3 protrudes from the housing 2 to the other end side S2 through the hole (through hole) of the end cover 26 formed along the rotation axis x.

[0013] Figure 3 is a cross-sectional view taken along line 3-3 of Figure 2. Referring to Figures 2 and 3 together, the motor 4 has a stator 40 and a rotor 41 that is rotatable relative to the stator 40. The stator 40 has a magnetic body (hereinafter referred to as the "yoke"), that is, a stator core 42, a coil 43, and an insulator 44. The stator core 42 is formed from a laminate in which a plurality of annular silicon steel sheets or electromagnetic steel sheets are laminated in the axial direction of the rotation axis. The stator core 42 is fixed to the inner peripheral surface of the outer peripheral portion 20a of the motor housing 20. The stator core 42 has a plurality of teeth 42a arranged circumferentially around the rotation axis x. The coil 43 is wound around each tooth 42a. The insulator 44 insulates the stator core 42 and the coil 43.

[0014] The stator 40 is covered with a predetermined member 45 (see Figure 2). The predetermined member 45 is formed from, for example, a resin material having thermal conductivity. A substrate (hereinafter referred to as a "printed circuit board") 46 is fixed to the other end side S2 of the predetermined member 45. The printed circuit board 46 is provided with a plurality of electronic components such as wiring for electrically connecting the coils, a temperature sensor for detecting temperature, and a magnetic sensor. This printed circuit board 46 is electrically connected to, for example, the outer peripheral surface of the rotating device 1 or another substrate provided outside. Alternatively, the printed circuit board 46 may be composed of a printed circuit board and a plurality of bus bars, and the printed circuit board and the plurality of bus bars may be electrically connected. A sensor (not shown) for detecting the torque acting on the crankshaft 3 is incorporated in the rotating device 1. A control circuit capable of determining the current value of the current supplied to the coil 43 based on the detected value of the torque from this sensor is mounted on the printed circuit board 46. Current is supplied to the coil 43 from, for example, a battery (not shown) mounted on the bicycle. In this way, the control circuit can control the rotation speed of the motor 4 according to the value of the torque of the crankshaft 3.

[0015] The rotor 41 has a magnet 47 and a magnetic body (hereinafter referred to as "yoke") 48. The yoke 48 is formed of, for example, a magnetic material. A plurality of magnets 47 arranged in the circumferential direction are supported by the yoke 48. The magnet 47 faces the outer peripheral surface of the magnetic pole portion (hereinafter referred to as "tooth") 42a of the stator core 42 with a predetermined magnetic gap. When current is supplied to the coil 43, the rotor 41 can rotate relative to the stator 40 about the rotation axis x due to the magnetic interaction between the coil 43 and the magnet 47. Note that the yoke 48 may be, for example, a cylindrical member centered on the rotation axis x, and the magnet 47 may be a single cylindrical permanent magnet, or a plurality of permanent magnets may be connected to each other in the circumferential direction to form a cylindrical shape.

[0016] The rotor 41 is attached to a motor shaft (rotation shaft) 49. The motor shaft 49 has a cylindrical main body 49a centered on the rotation axis x and a flange 49b extending radially from the outer peripheral surface of the main body 49a. The outer peripheral surface of the main body 49a is defined by a cylindrical surface centered on the rotation axis x, while the outer peripheral surface of the flange 49b is defined by a cylindrical surface having a central axis eccentric from the rotation axis x. The rotor 41 is fixed to the outer peripheral surface of the main body 49a, for example, by press fitting. The motor shaft 49 is supported so as to be relatively rotatable via a bearing 11 on the outer peripheral surface of the inner peripheral portion 20b of the motor housing 20 adjacent to the end portion on the other end side S2. The bearing 11 is a bearing having rolling elements, for example, a ball bearing. In the rotation axis direction, the inner peripheral surface of the main body 49b faces the outer peripheral surface of the crankshaft 3. In the gear housing 21, a speed reducer 5 described later is connected to the end portion on one end side S1 of the motor shaft 49.

[0017] The gear housing 21 has a cylindrical outer portion (hereinafter referred to as the "outer peripheral portion") 21a centered on the rotation axis x. A plate 28 is fixed to the inner peripheral surface of the outer peripheral portion 21a adjacent to the end portion on the other end side S2 of the outer peripheral portion 21a. In this example, the plate 28 is directly fixed to the outer peripheral portion 21a, but it may be indirectly fixed via other members. The gear cover 22 has a cylindrical outer portion (hereinafter referred to as the "outer peripheral portion") 22a centered on the rotation axis x and a cylindrical inner portion (hereinafter referred to as the "inner peripheral portion") 22b that is smaller in diameter and located inside the outer peripheral portion 22a and centered on the rotation axis x. A speed reducer 5 is housed in the gear housing 21 and the gear cover 22. The speed reducer 5 is arranged side by side with the motor 4 in the rotation axis direction. The plate 28 is formed in an annular shape extending across between the motor 4 and the speed reducer 5. That is, the speed reducer 5 is arranged on the opposite side of the motor 4 with the plate 28 interposed therebetween in the rotation axis direction.

[0018] FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2. FIG. 5 is a cross-sectional perspective view showing a state in which the gear cover 22 and the bearing 14 are removed from the rotating device 1. Referring to FIGS. 2, 4, and 5 together, the speed reducer 5, as an example, constitutes a cycloid speed reducer. The speed reducer 5 has a first gear 50 formed on the outer peripheral portion 21a of the gear housing 21, a second gear 51 arranged on the inner peripheral side of the first gear 50 and fitted to the first gear 50, and a third gear 52 arranged further on the inner peripheral side of the first gear 51 and fitted to the second gear 51. The first gear 50 is a fixed gear. The second gear 51 is a ring gear used as a planetary gear. The third gear 52 is supported on the outer peripheral surface of the flange 49b of the motor shaft 49 via a bearing 12. The bearing 12 is a bearing having rolling elements, for example, a ball bearing. As is clear from FIG. 2, the bearing 12 and the third gear 52 are arranged side by side in the rotation axis direction. The third gear 52 is supported on the outer peripheral surface of the main body 49a of the motor shaft 49 via a bearing 13. The bearing 13 is a bearing having rolling elements, for example, a ball bearing.

[0019] On the side portion, i.e., the inner peripheral portion 50a, of the first gear 50, a plurality of teeth 53 arranged in the circumferential direction are formed. On the side portion, i.e., the outer peripheral portion 51a, of the second gear 51, a plurality of teeth 54 arranged in the circumferential direction are formed. The outer peripheral portion 51a is surrounded by the first gear 50. On the side portion, i.e., the inner peripheral portion 51b, of the second gear 51, a plurality of teeth 55 arranged in the circumferential direction are formed. On the side portion, i.e., the outer peripheral portion 53a, of the third gear 52, a plurality of teeth 56 arranged in the circumferential direction are formed. As described above, since the outer peripheral surface of the flange 49b is a cylindrical surface having a central axis eccentric from the rotation axis x, the central axis x1 of the second gear 51 is eccentric from the rotation axis x. On the other hand, the central axes of the first gear 50 and the third gear 52 coincide with the rotation axis x. Thus, while the central axis x1 of the second gear 51 rotates around the rotation axis x, the second gear 51 rotates eccentrically with respect to the first gear 50 and the third gear 52.

[0020] In this example, the number of teeth 53 of the first gear 50 is larger than the number of teeth 54 of the outer peripheral portion 51a of the second gear 51. The number of teeth 54 of the outer peripheral portion 51a of the second gear 51 is larger than the number of teeth 55 of the inner peripheral portion 51b of the second gear 51. Similarly, the number of teeth 54 of the outer peripheral portion 51a of the second gear 51 is larger than the number of teeth 56 of the outer peripheral portion 52a of the third gear 52. When the motor shaft 49 rotates around the rotation axis x, due to the eccentricity and the difference in the number of teeth, a part of the teeth 54 of the second gear 51 meshes with a part of the teeth 53 of the first gear 50. At the same time, on the side opposite to the meshing with the first gear 50 across the rotation axis x, a part of the teeth 55 of the second gear 51 meshes with a part of the teeth 56 of the third gear 52. As a result, the second gear 51 rotates in a rotation direction opposite to the rotation direction of the motor shaft 49. At this time, the third gear 52 rotates in the same rotation direction as the rotation direction of the second gear 51. Thus, the rotation speed of the motor shaft 49 is reduced at a predetermined reduction ratio.

[0021] Returning to FIG. 2, the third gear 52 has a cylindrical main body 52b centered on the rotation axis x and a cylindrical protruding portion 52c centered on the rotation axis x protruding from the main body 52b to one end side S1. The main body 52b has teeth 56 on the outer peripheral portion 52a and is supported by the motor shaft 49 via a bearing 13 on the inner peripheral surface. The protruding portion 52c is supported on the outer peripheral surface of the output shaft 58 via a one-way clutch 57 on its inner peripheral surface, while being supported on the inner peripheral surface of the outer peripheral portion 22a of the gear cover 22 via a bearing 14 on its outer peripheral surface. The bearing 14 is a bearing having rolling elements, for example, a needle bearing. The output shaft 58 is formed in a cylindrical shape around the rotation axis x. The output shaft 53 is arranged side by side with the motor shaft 49 in the rotation axis direction.

[0022] The output shaft 58 is supported on the inner peripheral surface of the inner peripheral portion 22b of the gear cover 22 via a bearing 15 on its outer peripheral surface, while being supported on the outer peripheral surface of the crankshaft 3 via a bearing 16 on its inner peripheral surface. The bearing 15 and the bearing 16 are bearings having rolling elements, for example, ball bearings. The inner peripheral surface of the output shaft 58 and the outer peripheral surface of the crankshaft 3 facing each other are connected via a one-way clutch 59. Note that at least a part of the one-way clutches 57 and 59 is covered with a fluid, that is, a lubricant (not shown).

[0023] The one-way clutches 57 and 59 can transmit the rotational force of the third gear 52 to the output shaft 58 in one direction around the rotation axis x (that is, rotate the second gear 52 and the output shaft 58 in the same direction), while being configured to allow relative rotation between the third gear 52 and the output shaft 58 in the other direction around the rotation axis x. The end of the other end side S2 of the output shaft 58 faces the motor shaft 49, while the end of the one end side S1 of the output shaft 58 is arranged outside the gear cover 22. The end of the one end side S1 of the output shaft 58 is connected to a chain ring fixed to the crank arm on the one end side S1. Thus, the rotational force generated by the motor 4 is decelerated by the speed reducer 5 at a predetermined reduction ratio and transmitted from the output shaft 58 to the chain ring.

[0024] As shown in FIG. 5, the side portion 50a on the second gear 52 side of the outer peripheral portion 21a of the gear housing 21 has a curved surface 21b and the aforementioned first gear 50, that is, a plurality of teeth 53. In this example, in the rotational axis direction, the curved surface 21b and the teeth 53 are adjacent to each other. The curved surface 21b is formed, for example, in a cylindrical shape centered on the rotational axis x. The curved surface 21b is continuous in the circumferential direction. FIG. 6 is a perspective view schematically showing the structure of the plate 28 according to the first specific example. Referring to FIGS. 5 and 6 together, the plate 28 faces, in the rotational axis direction, the portion where the first gear 50 and the second gear 51 are engaged with each other, and is disposed at a predetermined distance from the portion where the first gear 50 and the second gear 51 are engaged with each other, the bearing 12 having rolling elements, and the flange 49b of the motor shaft 48. The plate 28 has an annular main body 29 around the rotational axis x. The main body 29 is formed in a flat plate shape extending along a virtual plane orthogonal to the rotational axis x. The main body 29 has a surface 29a that extends in the radial direction and the circumferential direction.

[0025] The main body 29 has an annular convex portion 31 at its outer peripheral side end (hereinafter referred to as the "outer peripheral portion") 30 and an annular convex portion 33 at its inner peripheral side end (hereinafter referred to as the "inner peripheral portion") 32. The convex portion 31 and the convex portion 33 extend from the surface 29a of the main body 29 to one side S1 in the rotational axis direction. In this example, the convex portion 31 and the convex portion 33 are formed continuously around the rotational axis x. Thus, a concave portion 34 is formed between the convex portion 31 and the convex portion 33 in the plate 28. The concave portion 34 extends in the radial direction and the circumferential direction and is surrounded by the convex portion 31 and the convex portion 33. In this example, the inner peripheral surface 31a of the convex portion 31 is an inclined surface that approaches the surface 29a of the main body 29 as it goes toward the inner peripheral side. As shown in FIG. 5, the plate 28 is fixed, for example, by press-fitting, at its outer peripheral portion 30, to the curved surface 21b of the gear housing 21. The inner peripheral portion 32 of the plate 28 faces the outer peripheral surface of the motor shaft 49 and is separated by a predetermined distance.

[0026] An example of the usage mode of the rotary device 1 as described above will be explained. When a user of a bicycle incorporating the rotary device 1 pedals to rotate the crank arm, the crankshaft 3 rotates around the rotation axis x. In this example, when viewed from one side S1, the crankshaft 3 rotates clockwise. When the torque sensor detects an increase in the torque acting on the crankshaft 3 equal to or greater than a predetermined threshold value, the control circuit of the printed circuit board 46, which is electrically connected from an external power source via another substrate, supplies current to the coil 43 of the motor 4. Due to the magnetic interaction between the coil 43 and the magnet 47, the rotor 41 rotates relative to the stator 40 around the rotation axis x. The rotational force generated by this rotation is transmitted from the motor shaft 49 to the speed reducer 5. The rotor 41 and the motor shaft 49 rotate counterclockwise when viewed from one side S1.

[0027] In the speed reducer 5, the rotational speed is decreased by the engagement of the first gear 50, the second gear 51, and the third gear 52, and the rotational force is transmitted from the second gear 52 to the output shaft 58. Note that due to the function of the speed reducer 5, the rotation direction of the motor shaft 49 is opposite to that of the output shaft 58. That is, when viewed from one side S1, the output shaft 58 rotates clockwise. The rotational force with the decreased rotational speed is transmitted from the output shaft 58 to the chain ring and the crankshaft 3. As a result, the rotational force of the motor 4 assists the rotation of the crank arm of the bicycle while increasing its torque. In this way, the user of the bicycle can easily pedal even in a situation where the torque is large, due to the rotational force of the motor 4.

[0028] In such a rotating device 1, the teeth 53 of the first gear 50 and the teeth 54 of the second gear 51 are at least partially covered with a lubricant W. Such a lubricant W may protrude in the axial direction of the rotating shaft from the region where the teeth 53 and 54 mesh, that is, the portion where the first gear 50 and the second gear 51 are fitted together. The plate 28 faces the portion where the first gear 50 and the second gear 51 are fitted together in the axial direction of the rotating shaft. Therefore, the lubricant W as a fluid protruding in the axial direction from the portion where the first gear 50 and the second gear 51 are fitted together or the lubricant W as a fluid leaking from the bearing 12 contacts the plate 28. In the plate 28, the lubricant W can be trapped in the recess 34 formed between the convex portion 31 and the convex portion 33. As a result, the scattering of the lubricant W from the speed reducer 5 to the motor 4 can be suppressed.

[0029] FIG. 7 is a perspective view schematically showing the structure of the plate 28A according to the second specific example. A plate 28A may be incorporated in the rotating device 1 instead of the aforementioned plate 28. Note that the same reference numerals are given to the same configurations as those of the plate 28. This plate 28A has one or a plurality of ribs 35 extending in the radial direction on the surface 29a of the main body 29 between the outer peripheral portion 30 and the inner peripheral portion 32. In this example, the plurality of ribs 35 extend in the circumferential direction as they extend in the radial direction from the inner peripheral portion 32 toward the outer peripheral portion 30. In this example, all the ribs 35 have the same shape. According to such a plate 28A, the lubricant W can be trapped between the ribs 35, 35 adjacent to each other in the circumferential direction within the recess 34.

[0030] FIG. 8 is a perspective view schematically showing the structure of the plate 28B according to the third specific example. The plate 28B may be incorporated into the rotating device 1 instead of the aforementioned plate 28. Note that the same reference numerals are given to the same configurations as those of the plate 28. This plate 28B has one or a plurality of ribs 36 extending in the circumferential direction between the outer peripheral portion 30 and the inner peripheral portion 32. In this example, a plurality of ribs 36 having different diameters are formed concentrically in the circumferential direction on the surface 29a of the main body 29. In this example, the distances between the adjacent ribs 36, 36 in the radial direction are set to be equal, but these distances may be different. According to such a plate 28B, the lubricant W can be trapped between the adjacent ribs 36, 36 in the radial direction within the recess 34.

[0031] FIG. 9 is a perspective view schematically showing the structure of the plate 28C according to the fourth specific example. The plate 28C may be incorporated into the rotating device 1 instead of the aforementioned plate 28. Note that the same reference numerals are given to the same configurations as those of the plate 28. This plate 28C has one or a plurality of ribs 37 arranged in the circumferential direction between the outer peripheral portion 30 and the inner peripheral portion 32. In this example, a plurality of ribs 37 having a herringbone shape (a shape having a bent portion bent in the circumferential direction) when viewed from the rotational axis direction are continuously formed in the circumferential direction on the surface 29a of the main body 29. Also, the formation of the convex portion 33 of the inner peripheral portion 32 is omitted, but the convex portion 33 may be formed on the inner peripheral portion 32. The inner peripheral portion 32 side of the rib 37 is formed from a spiral curve toward the rotation axis x. According to such a plate 28C, the lubricant W can be trapped between the adjacent ribs 37, 37 in the circumferential direction within the recess 34.

[0032] FIG. 10 is a perspective view schematically showing the structure of the motor shaft 49A according to the second specific example. The motor shaft 49A may be incorporated in the rotating device 1 instead of the aforementioned motor shaft 49. Note that the same reference numerals are assigned to the same configurations as those of the motor shaft 49. This motor shaft 49A has one or a plurality of ribs 49d extending radially on the surface 49c of the flange 49b facing the plate 28. In this example, the plurality of ribs 49d extend circumferentially as they extend radially, from the inner circumference to the outer circumference of the surface 49c. In this example, all the ribs 49d have the same shape. According to such a motor shaft 49A, the lubricant W can be trapped between the adjacent ribs 49d, 49d in the circumferential direction, so that the lubricant W can be surely stored between the surface 29a of the plate 28 and the surface 49c. Note that the flange 49b has a surface 49e facing away from the surface 49c. In this example, the surface 49e is defined parallel to the surface 49c. In this example, no rib 49d is formed on the surface 49e. Further, an annular convex portion may be formed at the outer peripheral side end of the surface 49c as necessary.

[0033] FIG. 11 is a perspective view schematically showing the structure of the motor shaft 49B according to the second specific example. The motor shaft 49B may be incorporated in the rotating device 1 instead of the aforementioned motor shaft 49. Note that the same reference numerals are assigned to the same configurations as those of the motor shaft 49. This motor shaft 49B has one or a plurality of ribs 49f extending circumferentially on the surface 49c. In this example, two ribs 49f having different diameters are formed concentrically in the circumferential direction on the surface 49c. According to such a motor shaft 49B, the lubricant W can be trapped between the adjacent ribs 49f, 49f in the radial direction, so that the lubricant W can be surely stored between the surface 29a of the plate 28 and the surface 49c.

[0034] FIG. 12 is a perspective view schematically showing the structure of a motor shaft 49C according to a third specific example. Instead of the aforementioned motor shaft 49, a motor shaft 49C may be incorporated into the rotating device 1. Note that the same reference numerals are given to the same configurations as those of the motor shaft 49. This motor shaft 49C has one or a plurality of ribs 49g arranged in the circumferential direction. In this example, a plurality of ribs 49g having a herringbone shape (a shape having a bent portion bent in the circumferential direction) when viewed from the axial direction of rotation are continuously formed in the circumferential direction on the surface 49c. According to such a motor shaft 49C, since the lubricant W can be trapped between the adjacent ribs 49g, 49g in the circumferential direction, the lubricant W can be reliably stored between the surface 29a of the plate 28 and the surface 49c.

[0035] In the motor shafts 49A, 49B, 49C shown in FIGS. 10 to 12, one or a plurality of similar ribs (not shown) may also be formed on the surface 49e on the side opposite to the surface 49c of the flange 49b. In this case, the ribs formed on the surface 49c of the flange 49b and the ribs formed on the surface 49e may have the same shape, for example, when viewed from one end side S1. For example, in the case of the rib 49d shown in FIG. 10, the rib 49d formed on the surface 49c and the rib 49d formed on the surface 49e may be formed in a curved shape extending in the same circumferential direction from the inner peripheral side to the outer peripheral side when viewed from one end side S1.

[0036] Note that although the rotating device 1 according to an embodiment of the present invention is incorporated into an electric assist bicycle, the rotating device 1 may be used for other applications such as industrial robots and machine tools instead of the electric assist bicycle. Further, although the speed reducer 5 described above constitutes a cycloid speed reducer as an example, it may be another type of speed reducer such as a harmonic gear speed reducer.

[0037] The embodiments described above are for facilitating the understanding of the present invention and are not for limiting and interpreting the present invention. Also, the above-described embodiments do not limit the objects to which the present invention is applied, and the present invention may include any object as its application target. Each component included in the above embodiments, as well as its arrangement, material, conditions, shape, size, etc. are not limited to those exemplified, and can be changed as appropriate. For example, the present invention includes differences that occur in the implementation of manufacturing tolerances and the like. Also, within a technically non-contradictory range, the components shown in different embodiments can be partially substituted or combined with each other. Further, each configuration can be appropriately and selectively combined so as to achieve at least a part of the above-described problems and effects.

Description of Reference Numerals

[0038] 1 Rotating machine, 10 Bearings, 11 Bearings, 12 Bearings, 13 Bearings, 14 Bearings, 15 Bearings, 16 Bearings, 2 Housing, 20 Motor housing, 20a Outer part (outer peripheral part), 20b Inner part (inner peripheral part), 20c Wall, 21 Gear housing, 21a Outer part (outer peripheral part), 21b Curved surface, 22 Gear cover, 22a Outer part (outer peripheral part), 22b Inner part (inner peripheral part), 23 Fastening part, 24 Annular member (gasket), 25 Annular member (gasket), 26 End cover, 27 Fastening part, 28, 28A, 28B, 28C Plates, 29 Body, 29a Surface, 30 Outer peripheral part, 31 Protrusion, 31a Inclined surface, 32 Inner peripheral part, 33 Protrusion, 34 Recess, 35, 36, 37 Ribs, 3 Crankshaft, 3a One end, 3b The other end, 4 Motor, 40 Stator, 41 Rotor, 42 Magnetic body (stator core), 42a Magnetic pole part (teeth), 43 Coil, 44 Insulator, 45 Predetermined member, 46 Substrate (printed circuit board), 47 Magnet, 48 Magnetic body (yoke), 49, 49A, 49B, 49C Motor shaft (rotating shaft), 49a Body, 49b Flange, 49c Surface, 49d Rib, 49e Surface, 49f Rib, 49g Rib, 5 Reducer, 50 First gear, 50a Inner peripheral part (side part), 51 Second gear, 51a Outer peripheral part (side part), 51b Inner peripheral part (side part), 52 Third gear, 52a Outer peripheral part (side part), 53 Teeth, 54 Teeth, 55 Teeth, 56 Teeth, 57 One-way clutch, 58 Output shaft, 59 One-way clutch, S1 One side, S2 The other side, W Lubricant, x Axis of rotation, x1 Central axis

Claims

1. a gear, a motor facing the gear in the direction of the rotation axis, a housing accommodating the gear and the motor, a plate directly or indirectly fixed to the housing, and the plate is a rotating device that crosses between the gear and the motor arranged in the direction of the rotation axis.

2. a side portion on the gear side of the housing includes a circumferentially continuous curved surface and a plurality of teeth arranged in the circumferential direction, and the outer peripheral portion of the plate is fixed to the curved surface. The rotating device according to claim 1.

3. the plate is fixed to the curved surface, and in the direction of the rotation axis, the plate faces a portion where the plurality of teeth of the housing and the gear are engaged with each other. The rotating device according to claim 2.

4. the plate includes a recess extending in the circumferential direction. The rotating device according to any one of claims 1 to 3.

5. the plate includes a surface extending in the circumferential direction and one or more ribs extending in the circumferential direction or one or more ribs extending in the radial direction, and the one or more ribs are provided on the surface extending in the circumferential direction. The rotating device according to any one of claims 1 to 3.

6. the plate includes an inner peripheral portion and an outer peripheral portion, and the inner peripheral portion includes an annular convex portion extending in the direction of the rotation axis, and the outer peripheral portion includes an annular convex portion extending in the direction of the rotation axis. The rotating device according to any one of claims 1 to 5.

7. a rotating shaft connected to the motor, and a bearing rotatably connecting the rotating shaft to the gear in the radial direction, and in the radial direction, the rotating shaft includes a flange extending toward the bearing, and one or more ribs extending in the circumferential direction or one or more ribs extending in the radial direction are provided on a surface of the flange facing the plate. The rotating device according to any one of claims 1 to 6.

8. the motor includes a stator and a rotor fixed to the rotating shaft, and in the direction of the rotation axis, the plate faces the stator or the rotor. The rotating device according to any one of claims 1 to 7.

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