Outboard Motor Water Pump Nesting for Vertical Size Reduction
Solution Overview
Problem
Conventional outboard motors are large in the vertical direction due to the placement of the water pump on the drive shaft, which obstructs other elements and increases the motor's size when attached to a boat.
Innovation Solution
The water pump is arranged with its pump shaft partially within the shift shaft, allowing it to rotate and be positioned lower than the drive shaft, reducing the overall vertical size of the outboard motor while maintaining water absorption capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the water pump is arranged on the drive shaft, then the water pump can be driven by the rotation of the drive shaft, but the outboard motor becomes large in the vertical direction
Solution Approach 1:
The pump shaft is arranged at least partially within the outer shape of the shift shaft when viewed from an axial direction of the shift shaft. This nesting arrangement allows the water pump to be positioned within the space occupied by the shift shaft, thereby reducing the vertical size of the outboard motor while maintaining the water pump's functionality.
Solution Approach 2:
Instead of arranging the water pump vertically along the drive shaft axis, the invention repositions it within the horizontal plane by nesting it within the shift shaft's outer shape. This dimensional reorganization reduces vertical clearance requirements while preserving the water pump's driving connection to the drive shaft.
2Ease of operation
If the water pump is arranged on the drive shaft, then the water pump can be positioned for water intake, but it obstructs other elements and increases the motor's size
Solution Approach 1:
The pump shaft is arranged at least partially within the outer shape of the shift shaft when viewed from an axial direction of the shift shaft. This nesting arrangement allows the water pump to be positioned within the space occupied by the shift shaft, thereby reducing the vertical size of the outboard motor while maintaining the water pump's functionality.
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 reduces the vertical size of the outboard motor without compromising water absorption capacity, allowing for a more compact design when attached to a boat.
Implementation Method 1
The pump shaft rotates according to the rotation of the drive shaft
Data Source
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AI summary
An engine includes a crankshaft extending in a vertical direction. A drive shaft is connected to the crankshaft and arranged coaxially with the crankshaft. A water intake passage is connected to the engine. A water pump is connected to the water intake passage. The water pump includes a pump shaft. The pump shaft is arranged eccentrically with respect to the drive shaft and in parallel with the drive shaft. The pump shaft rotates according to rotation of the drive shaft.