Blade rotation system

A blade rotation system, comprising:

• an hydraulic gear motor having a drive shaft, the drive shaft being configured with one or more first permanent magnets coupled thereto;
• wherein the hydraulic gear motor includes a gear system, and an inlet port and outlet port in fluid communication with the gear system and through which pressurized hydraulic fluid is passed to drive the hydraulic gear motor;
• a spindle shaft adapted for connection to a blade, the spindle shaft being configured with one or more second permanent magnets coupled thereto;
• wherein the one or more first permanent magnets are configured to magnetically engage the one or more second permanent magnets so that rotation of the drive shaft by the hydraulic gear motor translates into rotation of the spindle shaft to impart motion to the blade;
• wherein the hydraulic gear motor is configured such that as the pressurized hydraulic fluid passes from the inlet port to the outlet port, the hydraulic fluid drives the gear system to rotate the drive shaft and thus the spindle shaft to which the drive shaft is magnetically engaged;
• and
• a cup shape chamber, wherein the one or more first permanent magnets project axially into an open end of the cup shape chamber;
• wherein the cup shape chamber includes a flow passage for receiving a cooling fluid to cool the cup shape chamber.