Fan blade pitch change assembly
An assembly for changing the pitch of fan blades rotatably attached to a hub includes a main drive shaft configured to rotate the hub. The main drive shaft is rotated by a first motor. A secondary drive shaft is coupled to the main drive shaft via a gearing system located within the hub. The secondary drive shaft is also driven by a second motor. When driven by the second motor, the secondary drive shaft manipulates the gearing system to alter the pitch of the fan blades.
1. A fan blade pitch change mechanism comprising:
a first drive shaft configured to rotate a fan hub;
an actuator shaft coupled to a gear system disposed within the fan hub;
the actuator shaft configured to alter a blade pitch of a fan blade attached to the fan hub via the gear system;
a first motor attached to the first drive shaft;
the first motor configured to rotate the first drive shaft;
a second motor attached to the actuator shaft; and
the second motor configured to rotate the actuator shaft;
wherein the actuator shaft is disposed within the first drive shaft and the actuator shaft rotates with the first drive shaft,
wherein the actuator shaft acts as a drive shaft to rotate the second motor when the actuator shaft rotates with the first drive shaft.
2. The fan assembly according to claim 1 , wherein the second motor is coupled to the first drive shaft via the gear system.
3. The fan assembly according to claim 1 , wherein the second motor rotates according to the rotation of the first drive shaft.
4. The fan assembly according to claim 1 , wherein at least one of the first motor and the second motor comprise an electric motor.
5. The fan assembly according to claim 1 , wherein the actuator shaft is disposed within the first drive shaft.
6. The fan assembly according to claim 5 , wherein the actuator shaft extends from the second motor, through the first drive shaft, and into the fan hub.
7. The fan assembly according to claim 5 , wherein a bearing is disposed between the actuator shaft and the first drive shaft.
8. A fan comprising:
a hub;
a fan blade rotatably attached to the hub via a blade gear;
a pitch change gear disposed within the hub and operatively connected to the blade gear;
a first motor attached to the hub via a main drive shaft;
the main drive shaft configured to rotate the hub;
a second motor attached to the pitch gear via a secondary drive shaft;
the secondary drive shaft configured to change a blade pitch of the fan blade by rotating the pitch change gear;
wherein the secondary drive shaft is disposed within the main drive shaft and the secondary drive shaft rotates with the main drive shaft;
wherein the secondary drive shaft directly drives the second motor when the secondary drive shaft rotates with the main drive shaft.
9. The fan according to claim 8 , wherein the secondary drive shaft is disposed within the main drive shaft.
10. The fan according to claim 8 , wherein the second motor is configured to rotate the secondary drive shaft.
11. The fan according to claim 8 , wherein the second motor rotates according to the rotation of the main drive shaft.
12. The fan according to claim 8 , wherein the pitch change gear comprises a crown gear.
13. The fan according to claim 12 , wherein the blade gear comprises a crown gear operatively engaged with the pitch change gear.
14. The fan according to claim 8 , wherein the fan is configured to be incorporated into a cooling system.
15. The fan according to claim 14 , wherein the cooling system is disposed in a motor vehicle.
16. A cooling system for a motor vehicle comprising:
a radiator;
a variable pitch fan including a hub,
a fan blade rotatably attached to the hub via a blade gear,
a pitch change gear disposed within the hub and operatively connected to the blade gear,
a first driver attached to the hub via a main drive shaft,
the main drive shaft configured to rotate the hub,
a second driver attached to the pitch gear via a secondary drive shaft, and
the secondary drive shaft configured to change a blade pitch of the fan blade by rotating the pitch change gear;
wherein the secondary drive shaft is disposed within the main drive shaft and the secondary drive shaft rotates with the main drive shaft;
wherein the secondary drive shaft rotates the second driver when the secondary drive shaft rotates with the main drive shaft; and
a control system configured to control the operation of the fan.
17. The cooling system of claim 16 , wherein the control system is configured to send a signal to the first motor to manipulate a rotational speed of the hub.
18. The cooling system of claim 16 , wherein the control system is configured to send a signal to the second motor to manipulate the pitch of the fan blade.
19. The cooling system of claim 16 , wherein the first and second drivers are electric motors.
20. The cooling system of claim 16 , wherein the second driver is configured to rotate the secondary drive shaft.