Motor and speed reducer housing with cooling for an electric vehicle
A driving apparatus for an electric vehicle includes (a) an electric motor including a rotary shaft and a rotor that is rotatably supported by the rotary shaft, (b) a speed reducer configured to reduce a speed of rotation of the rotary shaft of the electric motor and to output the rotation of the rotary shaft, and (c) a housing that houses the electric motor and the speed reducer. The housing is partitioned by a partition wall into an electric motor room in which the electric motor is housed and a speed reducer room in which the speed reducer is housed. A first refrigerant used in the electric motor room and a second refrigerant used in the speed reducer room are different from each other. At least a part of the speed reducer room is received in the electric motor room in an axial direction of the rotary shaft.
1 . A driving apparatus for an electric vehicle, the driving apparatus comprising:
an electric motor including a rotary shaft and a rotor that is rotatably supported by the rotary shaft;
a speed reducer configured to reduce a speed of rotation of the rotary shaft of the electric motor and to output the rotation of the rotary shaft; and
a housing that houses the electric motor and the speed reducer,
wherein the housing is partitioned by a partition wall into a first portion including an electric motor room in which the electric motor is housed and a second portion including a speed reducer room in which the speed reducer is housed,
wherein a first refrigerant used in the electric motor room is different from a second refrigerant used in the speed reducer room, and
wherein an end portion of the second portion of the housing is inserted into the first portion of the housing such that a part of the speed reducer room is received in the electric motor room in an axial direction of the rotary shaft.
2 . The driving apparatus according to claim 1 ,
wherein a space is defined by a part of the electric motor room, the part of the electric motor room overlapping with at least the part of the speed reducer room as viewed in a radial direction of the rotary shaft, and
wherein a power cable connected to the electric motor or a fluid pump configured to supply the first refrigerant into the electric motor room is provided in the space.
3 . A driving apparatus for an electric vehicle, the driving apparatus comprising:
an electric motor including a rotary shaft and a rotor that is rotatably supported by the rotary shaft;
a speed reducer configured to reduce a speed of rotation of the rotary shaft of the electric motor and to output the rotation of the rotary shaft;
a housing that houses the electric motor and the speed reducer,
wherein the housing is partitioned by a partition wall into an electric motor room in which the electric motor is housed and a speed reducer room in which the speed reducer is housed,
wherein a first refrigerant used in the electric motor room is different from a second refrigerant used in the speed reducer room, and
wherein at least a part of the speed reducer room is received in the electric motor room in an axial direction of the rotary shaft;
a second electric motor in addition to the electric motor; and
a second speed reducer in addition to the speed reducer,
wherein the electric motor and the second electric motor are housed in the electric motor room, and are located in respective positions that are symmetrical to each other with respect to a widthwise center line of the electric motor room,
wherein the speed reducer and the second speed reducer are housed in the speed reducer room, and are located in respective positions that are symmetrical to each other with respect to the widthwise center line,
wherein each of the speed reducer and the second speed reducer includes:
an input shaft connected in series to a corresponding one of the electric motor and the second electric motor;
a counter shaft disposed in parallel to the input shaft;
an output shaft disposed perpendicular to the counter shaft, and
a pair of reduction gears which are disposed between the counter shaft and the output shaft and which consist of hypoid gears.
4 . The driving apparatus according to claim 1 , wherein a width of the electric motor room in a lateral direction is greater than a width of the speed reducer room in the lateral direction.
5 . The driving apparatus according to claim 1 , wherein the speed reducer includes an input shaft connected in series to the rotary shaft, an output shaft perpendicular to the input shaft, and a pair of reduction gears comprising a small-diameter bevel gear fixed to the input shaft and a large-diameter bevel gear fixed to the output shaft.
6 . The driving apparatus according to claim 1 , wherein a space is defined by a part of the first portion of the housing, the part of the first portion of the housing overlapping with a part of the second portion of the housing as viewed in a radial direction of the rotary shaft, and wherein a power cable connected to the electric motor is in the space.
7 . The driving apparatus according to claim 1 , wherein a space is defined by a part of the first portion of the housing, the part of the first portion of the housing overlapping with a part of the second portion of the housing as viewed in a radial direction of the rotary shaft, and wherein a fluid pump configured to supply the first refrigerant into the electric motor room is in the space.
8 . The driving apparatus according to claim 1 , wherein the rotary shaft and an input shaft of the speed reducer are connected in series to each other through the partition wall.