Motorcycle Intake Valve Layout for Compact Tumble Actuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing intake control devices for saddle-type vehicles, such as motorcycles, are not compact and do not effectively protect intake control valves like the tumble control valve, leading to spatial constraints and potential weight imbalance.
Innovation Solution
The actuator of the tumble control valve is positioned behind the cylinder portion, surrounded by the cylinder, intake passage, and main frame, while the throttle valve actuator is positioned outside the vehicle's left-right center line, ensuring compact placement and balanced weight distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a tumble control valve and throttle valve are both provided in the intake passage, then intake control functionality is improved, but the device becomes less compact and harder to protect
Solution Approach 1:
The tumble control valve actuator is nested within the dead space formed by the cylinder portion, intake passage, and main frame. This nesting approach allows the actuator to be positioned in an otherwise unused space, achieving compact arrangement without compromising the intake control functionality provided by both valves
Solution Approach 2:
The actuator is positioned in the vertical dimension (behind the cylinder portion) rather than extending the intake passage horizontally. This dimensional change allows both valves to coexist in a compact configuration by utilizing the vertical space above the dead space
2Device complexity
If both actuators are positioned on the same side of the intake passage, then device complexity is reduced, but weight balance deteriorates
Solution Approach 1:
The actuators are positioned asymmetrically with respect to the vehicle's left-right center line. The tumble control valve actuator is positioned inside the dead space (closer to center), while the throttle valve actuator is positioned outside (farther from center). This asymmetric arrangement balances the weight distribution while maintaining simple device structure
3Ease of manufacture
If the connecting tube is bent with large angles to connect upstream components, then spatial arrangement is simplified, but intake air flow deteriorates
Solution Approach 1:
The connecting tube is designed with smooth curved transitions instead of sharp bends. The tube extends rearward from the cylinder head with controlled curvature, allowing smooth intake air flow while achieving the necessary spatial connection between components
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 improves intake performance by maintaining a smooth air flow and enhances the responsiveness of the intake control system without increasing the vehicle's size or reducing its rigidity.
Implementation Method 1
generates a vortex flow such as a tumble flow in an air-fuel mixture in a combustion chamber
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a compact and protected intake control device in a case where a saddle-type vehicle internal combustion engine includes an intake control valve such as a tumble control valve in addition to a throttle valve. In an intake control device for an in-vehicle internal combustion engine including a throttle valve 81 provided in an intake passage 6 that intake air passes to a combustion chamber 38 of an internal combustion engine 3 and controlled to any given opening degree to control an intake air amount, and a tumble control valve 71 that is provided downstream of the throttle valve and that opens and closes a passage cross section of a main passage of the intake passage divided into the main passage 6A and a tumble passage 6B along a passage direction to control intake air supply to the main passage, an actuator 72 that drives the tumble control valve is positioned behind a cylinder portion 32 of the internal combustion engine, is positioned closer to a vehicle left-right center line than the intake passage in plan view, and is positioned such that at least a part thereof overlaps a main frame 21 of a vehicle body frame 2 in plan view.