Marine Propulsion Cooling Pump With One-Way Impeller Drive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of a motor as a power source in marine propulsion devices leads to a significant reduction in the lifespan of the impeller in rotary variable displacement water pumps due to frequent changes in rotation direction, necessitating a shift mechanism that complicates the structure and increases costs.
Innovation Solution
A marine propulsion device with a motor that switches rotation direction via electrical control, incorporating a one-way clutch to connect the impeller of the water pump to the output shaft or a rotation transmission member, ensuring the impeller rotates only in one direction, thereby preventing rotation direction changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a motor is used as a power source with frequent rotation direction changes, then the propulsion system becomes more adaptable, but the impeller lifespan is significantly reduced
Solution Approach 1:
The patent segments the rotation transmission path by introducing a one-way clutch between the motor output shaft and the impeller. This allows the motor to rotate in both directions for adaptability while the impeller rotates in only one direction, protecting it from damage. The one-way clutch acts as a separator that decouples the bidirectional motor rotation from the unidirectional impeller rotation requirements.
2Ease of operation
If a shift mechanism is added to control rotation direction, then the propulsion system gains directional control, but the device complexity increases
Solution Approach 1:
The patent replaces complex mechanical shift mechanisms with an electrical control system for the motor. The motor's rotation direction is controlled electrically, and combined with the one-way clutch, this achieves directional control without requiring mechanical gears, clutches, or shift mechanisms. This substitution dramatically simplifies the overall structure while maintaining full directional control capability.
3Duration of action of moving object
If a one-way clutch is introduced to protect the impeller, then the impeller lifespan is maintained, but the device complexity increases
Solution Approach 1:
The one-way clutch serves multiple functions simultaneously: it protects the impeller from reverse rotation damage, enables the motor to operate in both directions for propulsion and reversal, and eliminates the need for separate mechanical shift mechanisms. This multi-functionality justifies the added component by providing multiple benefits rather than simply increasing complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration maintains the impeller's lifespan, allowing for a simplified, miniaturized, and cost-effective design without a shift mechanism, using a rotary variable displacement water pump with a rubber impeller.
Implementation Method 1
an impeller of the water pump is connected via a one-way clutch to the output shaft, the drive shaft, or a rotation transmission member other than the drive shaft
Implementation Method 2
a cooling mechanism configured to cool the motor, and a water pump configured to send water outside the marine propulsion device to the cooling mechanism
Data Source
AI summary
A marine propulsion device for propelling a boat is provided The marine propulsion device includes a motor including an output shaft, a drive shaft configured to rotate upon receiving a rotation of the output shaft, a propeller shaft provided with a propeller and configured to be rotated upon receiving a rotation of the drive shaft, and a cooling device. The cooling device includes a cooling mechanism configured to cool the motor, and a water pump configured to send water outside the marine propulsion device to the cooling mechanism. An impeller of the water pump is connected via a one-way clutch to the output shaft, the drive shaft, or a rotation transmission member other than the drive shaft provided in the marine propulsion device and configured to rotate by the rotation of the output shaft.