Power door opening/closing apparatus

1. A power door opening and closing apparatus arranged to open and close a door by a power of a motor, the power door opening and closing apparatus comprising:

a first unit including the motor, a first unit case connected to the motor, a first transmission mechanism received in the first unit case, and arranged to transmit a rotation of the motor, and a rotation sensor which is received within the first unit case, the rotation sensor being one of a plurality of electrical components, and being arranged to sense a rotation of the first transmission mechanism; and

a second unit which includes a second unit case connected to the first unit case by a fixing member, a second transmission mechanism rotatably received within the second unit case, and connected to the first transmission mechanism, and an output shaft connected to an output side of the second transmission mechanism, and arranged to transmit a rotation of the second transmission mechanism to the door, and which does not include an electrical component.

2. The power door opening and closing apparatus as claimed in claim 1 , wherein:

the first unit case has a substantially cylindrical shape;

the first unit case is connected to the motor so that the first unit case has a central axis which corresponds to a rotation axis of a rotation shaft of the motor;

the first transmission mechanism is supported to be rotated coaxially to the rotation axis of the rotation shaft of the motor; and

the first transmission mechanism includes a first input portion connected to the rotation shaft of the motor, and a first output portion arranged to be rotated in accordance with a rotation of the first input portion.

3. The power door opening and closing apparatus as claimed in claim 2 , wherein:

the first transmission mechanism includes an electromagnetic clutch which is received within the first unit case, and which is one of the plurality of electrical components, and

the electromagnetic clutch is arranged to switch a connection state in which the first transmission mechanism is arranged to output the rotation of the rotation shaft of the motor from the first output portion, and a disconnection state in which the first transmission mechanism is arranged so as not to output the rotation of the rotation shaft of the motor from the first output portion; and

the first output portion is an armature of the electromagnetic clutch.

4. The power door opening and closing apparatus as claimed in claim 2 , wherein:

the second unit case has a substantially cylindrical shape;

the second unit case is connected to the first unit case so that the second unit case has a central axis which corresponds to the rotation axis of the rotation shaft of the motor;

the second transmission mechanism is supported to be rotated coaxially with the rotational axis of the rotational shaft of the motor; and

the second transmission mechanism includes a second input portion connected to the first output portion, and a second output portion which is arranged to be rotated in accordance with a rotation of the second input portion, and which is connected to the output shaft.

5. The power door opening and closing apparatus as claimed in claim 4 , wherein:

the second transmission mechanism is a planetary gear mechanism;

the second input portion is a sun gear of the planetary gear mechanism;

the second output portion is a planetary carrier plate of the planetary gear mechanism; and

the second unit case includes internal teeth of the planetary gear mechanism which are formed on an inner circumference surface of the second unit case.

6. A method of assembling a power door opening and closing apparatus as claimed in claim 1 , the method comprising:

assembling the first unit including the motor, the first unit case, the first transmission mechanism, and the rotation sensor,

assembling the second unit including the second unit case, the second transmission mechanism, and the output shaft, and

connecting the first unit case to the second unit case,

wherein the first unit and the second unit are assembled independently.