Marine Propulsion Patents (Class 440)
- Variable pitch (Class 440/50)
- Combined with rudder (Class 440/51)
- With vibration dampening (Class 440/52)
- With means effecting or facilitating movement of propulsion unit or a segment of the propulsion unit (e.g., tilting or steering) (Class 440/53)
- Having means to control flow around propeller (Class 440/66)
- Propeller guard (Class 440/71)
- Self-clearing (Class 440/73)
- Shaft braking or locking (Class 440/74)
- Having transmission (Class 440/75)
- Propulsion unit casing (Class 440/76)
- Propeller arrangement (Class 440/79)
- Shafting (Class 440/83)
