MOTOR

Abstract

A motor (1) comprising: a rotor (20) arranged to rotate about a motor axis (J2); and a stator (30) arranged radially outside the rotor (20); wherein the rotor (20) comprises: a shaft (21) arranged to extend along the motor axis (J2) and arranged to have a casing portion (21c) and a screw portion (21d) arranged along an axial direction on an outer peripheral surface thereof; a rotor core (24) arranged to surround the shaft (21) from the radial outside; a rotor magnet (25) fixed to the rotor core (24); a pair of end plates (26) arranged on both axial sides of the rotor core (24); and a nut (29) screwed onto the screw portion (21d);the rotor core (24) and the pair of end plates (26) are held between the casing portion (21c) and the nut (29);wherein the pair of end plates (26) includes:a first end plate (26A) held between the casing portion (21c) and the rotor core (24); anda second end plate (26B) held between the nut (29) and the rotor core (24); and wherein each of the pair of end plates (26) comprises a first surface (26a) disposed opposite an axial end surface (24a) of the rotor core (24) and a second surface (26b) disposed to face away from the first surface (26a); the first surface (26a) comprises an inclined surface (26e) disposed to incline toward the rotor core (24) while the inclined surface (26e) extends radially outward;the inclined surface (26e) is arranged to be in contact with the axial end surface (24a) of the rotor core (24); each of the end plates (26) includes: a plate through-hole (26p) arranged radially inward from the inclined surface (26e) and arranged to extend in the axial direction, and a second recessed portion (26k) arranged in the second surface (26b) and arranged to extend radially outward from the plate through-hole (26p); the nut (29) and second end plate (26B) are arranged to have a washer (28) interposed therebetween; the plate through-hole (26p) of the first end plate (26A) is covered by the casing portion (21c); andthe plate through hole (26p) of the second end plate (26B) is covered by the disc (28);

Claims

[1] An engine (1) having the following features: a rotor (20) arranged to rotate about a motor axis (J2); and a stator (30) arranged radially outside the rotor (20); wherein the rotor (20) has the following features: a shaft (21) arranged to extend along the motor axis (J2) and arranged to have a casing portion (21c) and a screw portion (21d) arranged along an axial direction on an outer peripheral surface thereof; a rotor core (24) arranged to surround the shaft (21) from the radial outside; a rotor magnet (25) attached to the rotor core (24); a pair of end plates (26) arranged on both axial sides of the rotor core (24); and a nut (29) screwed onto the screw portion (21d); the rotor core (24) and the pair of end plates (26) are held between the casing portion (21c) and the nut (29); wherein the pair of end plates (26) includes: a first end plate (26A) held between the casing portion (21c) and the rotor core (24); and a second end plate (26B) held between the nut (29) and the rotor core (24); and wherein each of the pair of end plates (26) includes a first surface (26a) disposed opposite an axial end surface (24a) of the rotor core (24) and a second surface (26b) disposed to face away from the first surface (26a); the first surface (26a) comprises an inclined surface (26e) arranged to incline toward the rotor core (24) while the inclined surface (26e) extends radially outward; the inclined surface (26e) is arranged to be in contact with the axial end surface (24a) of the rotor core (24); each of the end plates (26) contains: a plate through-hole (26p) arranged radially inwardly of the inclined surface (26e) and arranged to extend in the axial direction, and a second recessed portion (26k) disposed in the second surface (26b) and arranged to extend radially outward from the plate through-hole (26p); the nut (29) and second end plate (26B) are arranged to have a washer (28) interposed therebetween; the plate through-hole (26p) of the first end plate (26A) is covered by the enclosure portion (21c); and the plate through hole (26p) of the second end plate (26B) is covered by the disc (28). [2] The engine (1) according to claim 1, wherein the rotor core (24) includes a magnet holding hole (24d) arranged to pass therethrough along the axial direction; the rotor magnet (25) is inserted into the magnet holding hole (24d); and the inclined surface (26e) is arranged to close an opening of the magnet holding hole (24d). [3] The engine (1) according to one of claims 1 and 2, in which the shaft (21) comprises a hollow portion (22) having an inner circumferential surface arranged to extend along the axial direction and communication holes (23) each arranged to extend in a radial direction to bring a space outside the shaft (21) and the hollow portion (22) into communication with each other, the hollow portion (22) being arranged to guide oil therein; each of the pair of end plates (26) includes a first recessed portion (26j) disposed in the first surface (26a) and arranged to extend radially inward from the plate through-hole (26p); the first recessed portion (26f) is connected to a corresponding one of the communication holes (23) at a radially inner end thereof; the rotor core (24) is arranged to cover an opening of the first recessed portion (26f); the second recessed portion (26k) of the first end plate (26A) comprises an axially facing opening including a covered portion covered by the skirt portion (21c) and an open portion (26s) not covered by the skirt portion (21c); and the second recessed portion (26k) of the second end plate (26B) comprises an axially facing opening including a covered portion covered by the disk (28) and an open portion (26r) not covered by the disk (28). [4] The engine (1) according to any one of claims 1 to 3, wherein the shaft (21) comprises a hollow portion (22) having an inner circumferential surface arranged to extend along the axial direction, and communication holes (23) each arranged to extend in a radial direction to bring a space outside the shaft (21) and the hollow portion (22) into communication with each other, the hollow portion (22) being arranged to guide oil therein; each end plate (26) includes a first recessed portion (26f) disposed in the first surface (26a) and arranged to extend radially inwardly from the plate through-hole (26p); the first recessed portion (26j) is connected to a corresponding one of the communication holes (23) at a radially inner end thereof; the rotor core (24) is arranged to cover an opening of the first recessed portion (26f); the rotor core (24) comprises a rotor through-hole (24e) arranged to pass therethrough along the axial direction; the rotor core through-hole (24e) is arranged to connect the first recessed portions (26j) of the pair of end plates (26) to each other; and at least a portion of an opening of the core through-hole (24e) is arranged radially outward from the plate through-hole (26p). [5] The engine (1) according to claim 1, wherein a skew angle θ refers to an angle defined by the inclined surface (26e) and a plane perpendicular to the motor axis (J2); the inclined surface (26e) is arranged to incline at a skew angle α toward the rotor core (24) while extending radially outward; and the inclination angle α of the inclined surface (26e) is in the range from 0.1° to 5° inclusive. [6] The engine (1) according to claim 1, wherein a bottom portion of each second recessed portion (126k) comprises an inclined surface (126u) arranged to decrease the depth of the second recessed portion (126k) with decreasing distance from a radially outer end; and the inclined surface (126u) is arranged to overlap with the open portion (126r) when viewed in the axial direction. [7] The engine (1) according to claim 1, wherein the second excepted section contains a pair of second excepted sections (226k); and the pair of second recessed portions (226k) are arranged to have different shapes when viewed in the axial direction [8] The engine (1) according to claim 1, wherein the second recessed portion (226k) is arranged to curve to increase a skew angle thereof with respect to the radial direction while extending radially outward. [9] The engine (1) according to claim 1, wherein the end plate (26) is circular in plan view. [10] The engine (1) according to claim 1, wherein the end plate (26) is made of a metal. [11] The engine (1) according to claim 1, wherein the second recessed portion (26k) is covered by the disk (28).

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