Drive device and drive device unit

1 . A drive device configured to drive a rotor of a flight vehicle to rotate the rotor, the drive device comprising:

a heat generator configured to generate heat when driven to rotate the rotor;

a housing accommodating the heat generator and having an outer peripheral surface extending along a rotation axis of a fan, the fan configured to send a gas; and

a radiation fin extending along the outer peripheral surface in an axial direction in which the rotation axis extends, and configured to release the heat from the heat generator to the gas that flows along the outer peripheral surface due to rotation of the fan, wherein

the radiation fin includes an inclined fin provided on the outer peripheral surface, and

at least a part of the inclined fin is inclined in a circumferential direction of the rotation axis with respect to the rotation axis,

the outer peripheral surface includes

a first heat region to which the heat from the heat generator is to be applied, and

a second heat region aligned with the first beat region in the circumferential direction, such that a separation distance between the heat generator and the second heat region is larger than a separation distance between the heat generator and the first heat region, and

at least a part of the inclined fin is inclined to guide the gas to the first beat region.

2 . The drive device according to claim 1 , wherein

the fan is configured to generate a swirling flow in which the gas flows in a direction inclined in the circumferential direction with respect to the rotation axis,

the inclined fin includes a forward inclined fin provided on the outer peripheral surface, and

at least a part of the forward inclined fin is inclined to extend along the swirling flow.

3 . The drive device according to claim 1 , further comprising:

an obstacle provided on the outer peripheral surface and configured to restrict the gas from flowing in the axial direction, wherein

the outer peripheral surface includes

an axial arrangement region aligned with the obstacle in the axial direction and located on an opposite side of the obstacle from the fan in the axial direction, and

a circumferential arrangement region aligned with the axial arrangement region in the circumferential direction, and

at least a part of the inclined fin is inclined to guide the gas from the circumferential arrangement region to the axial arrangement region.

4 . The drive device according to claim 1 , wherein

the inclined fin is provided at a position separated from the second heat region and the first heat region toward an upstream side in the axial direction, and

at least a part of the inclined fin is inclined to extend toward the first heat region.

5 . The drive device according to claim 1 , wherein

a heat generation member constituting the heat generator is attached to an inner peripheral surface of the housing,

the first heat region is located at a position overlapped with the heat generation member in a radial direction of the rotation axis, and

the second heat region is located at a position not overlapped with the heat generation member in the radial direction.

6 . The drive device according to claim 1 , wherein

the first heat region is a fin region in which the radiation fin is provided, and

the second heat region is a finless region in which no radiation fin is provided.

7 . The drive device according to claim 1 , wherein

in the inclined fin, an upstream portion extends from a fin upstream end, which is an upstream-side end portion, toward a downstream side, and

at least the upstream portion is inclined.

8 . The drive device according to claim 1 , wherein

the radiation fin includes a parallel fin extending parallel to the rotation axis, and

the parallel fin is provided on the outer peripheral surface on a downstream side of the inclined fin with respect to a flow of the gas.

9 . A drive device configured to drive a rotor of a flight vehicle to rotate the rotor, the drive device comprising:

a heat generator configured to generate heat when driven to rotate the rotor;

a housing accommodating the heat generator and having an outer peripheral surface extending along a rotation axis of a fan, the fan configured to send a gas;

a radiation fin extending along the outer peripheral surface in an axial direction in which the rotation axis extends, and configured to release the heat from the heat generator to the gas that flows along the outer peripheral surface due to rotation of the fan;

a housing cover having a cover inner peripheral surface opposed to the outer peripheral surface and attached to the housing to cover the radiation fin from an outer peripheral side, and

a cover fin provided on the cover inner peripheral surface, protruding from the cover inner peripheral surface toward the outer peripheral surface, and configured to guide the gas to the inclined fin, wherein

the radiation fin includes an inclined fin provided on the outer peripheral surface, and

at least a part of the inclined fin is inclined in a circumferential direction of the rotation axis with respect to the rotation axis.

10 . A drive device unit to be mounted on a flight vehicle, the drive device unit comprising:

a drive device configured to drive a rotor of the flight vehicle to rotate the rotor; and

a fan configured to rotate about a rotation axis to send a gas and aligned with the drive device along the rotation axis, wherein

the drive device includes

a heat generator configured to generate heat when driven to rotate the rotor,

a housing accommodating the heat generator and having an outer peripheral surface extending along the rotation axis of the fan, the fan configured to send the gas, and

a radiation fin extending along the outer peripheral surface in an axial direction in which the rotation axis extends, and configured to release the heat from the heat generator to the gas that flows along the outer peripheral surface due to rotation of the fan,

the radiation fin includes an inclined fin provided on the outer peripheral surface, and

at least a part of the inclined fin is inclined in a circumferential direction of the rotation axis with respect to the rotation axis; the drive device unit further comprising:

a shroud aligned with the housing along the rotation axis and covering the fan from a radially outer side of the rotation axis; and

a shroud fin provided on an inner peripheral surface of the shroud, protruding from the inner peripheral surface toward the outer peripheral surface, and configured to guide the gas to the inclined fin.

11 . The drive device according to claim 9 , wherein

the cover fin and the radiation fin are adjacent to each other in the axial direction.

12 . The drive device unit according to claim 10 , wherein

the shroud fin and the radiation fin are adjacent to each other in the axial direction.