Valve Timing Control Apparatus Reducing Pressure Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing valve opening/closing timing control apparatuses face challenges in maintaining good responsiveness without complicating or enlarging the flow path configuration, often resulting in pressure loss and reduced operational efficiency.
Innovation Solution
A valve opening/closing timing control apparatus featuring a driving side rotator and a driven side rotator connected by a connecting bolt with advanced and retarded angle ports, a sleeve with communication holes, and a fluid supply pipe that supplies fluid linearly along the rotation axis, eliminating the need for complex flow paths and reducing pressure loss by discharging fluid outward through a drain flow path formed between the connecting bolt and sleeve.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the hydraulic oil is supplied from the oil pump to the sleeve through the introduction path formed between the outer periphery of the connecting bolt and the inner periphery of the sleeve, then the flow path configuration is simplified, but the pressure loss of the introduction path occurs which causes deterioration in responsiveness
Solution Approach 1:
The patent extracts the fluid supply function from the introduction path between the connecting bolt and sleeve, and implements it through a dedicated fluid supply pipe that penetrates the connecting bolt. This separates the supply function from the structural connection function, eliminating pressure loss in the introduction path while maintaining simplified overall configuration.
Solution Approach 2:
The patent introduces a fluid supply pipe as an intermediary component that directly connects the oil pump to the sleeve through the connecting bolt. This intermediary structure provides a dedicated fluid passage that eliminates the pressure loss issues of the original introduction path configuration.
2Loss of energy
If a valve unit is provided inside the connecting bolt to control the hydraulic oil, then the distance between the advanced angle chamber or retarded angle chamber and the valve unit is reduced so that pressure loss is reduced and good responsiveness is achieved, but the flow path becomes complicated and increased in size
Solution Approach 1:
The connecting bolt serves multiple functions: it mechanically connects the driven side rotator to the camshaft, provides structural support, and acts as a housing for the valve unit and fluid supply passage. This multi-functionality integrates the flow path control within an existing component, reducing overall complexity while maintaining short flow paths.
Solution Approach 2:
The valve unit and fluid supply pipe are nested within the connecting bolt structure. The valve unit is positioned inside the connecting bolt, and the fluid supply pipe penetrates through the connecting bolt to supply fluid directly to the valve unit, creating a compact nested arrangement that minimizes flow path length without increasing external dimensions.
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
The apparatus operates with improved responsiveness and simplified flow paths, allowing for arbitrary setting of the relative rotation phase speed without increasing the complexity or size of the flow path configuration, while minimizing pressure loss and fluid leakage.
Implementation Method 1
a fluid supply pipe that supplies fluid linearly along the rotation axis
Implementation Method 2
a drain flow path is formed at a boundary between an inner surface of the connecting bolt and an outer surface of the sleeve to discharge a fluid, which is from a drain hole formed in the sleeve to an outer surface side of the sleeve, outward from a head portion side of the connecting bolt
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A valve opening/closing timing control apparatus (A) includes: a driving side rotator (20) configured to rotate synchronously with a crankshaft (1) of an internal combustion engine (E); a driven side rotator (30) disposed coaxially with a rotation axis (X) of the driving side rotator and configured to rotate integrally with a valve opening/closing camshaft (5); a connecting bolt (40) disposed coaxially with the rotation axis to connect the driven side rotator to the camshaft, and having an advanced angle port (41a) and a retarded angle port (41b) formed to extend from an outer peripheral surface to an inner space (40S) thereof, the advanced angle port and the retarded angle port communicating with an advanced angle chamber (Ca) and a retarded angle chamber (Cb) between the driving side rotator and the driven side rotator, respectively; and a valve unit (Vb) disposed in the inner space of the connecting bolt.