Chain Tensioner Sleeve Structure for Smooth Plunger Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing chain tensioners exhibit poor followability to chain slack and high oil consumption, primarily due to pressure fluctuations in the cylindrical space during plunger movement, which interferes with the plunger's movement and leads to inefficient hydraulic oil usage.
Innovation Solution
The chain tensioner design includes a tubular cylinder with a plunger and sleeve, featuring a pressure chamber, leakage gap, and communication passage, where hydraulic oil flows into the cylindrical space as the volume increases, maintaining pressure and reducing oil discharge, and leaks back into the sleeve as the volume decreases, optimizing plunger movement and oil consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If hydraulic oil is not supplied into the cylindrical space during plunger movement, then the structure remains simple, but the pressure in the cylindrical space decreases and interferes with plunger movement
Solution Approach 1:
The patent introduces a communication passage as an intermediary channel that connects the cylindrical space to the hydraulic oil supply system. This passage allows hydraulic oil to flow into the cylindrical space, maintaining pressure and ensuring smooth plunger movement without requiring complex additional control mechanisms.
Solution Approach 2:
The patent applies hydraulic principles by utilizing hydraulic oil pressure to maintain the pressure in the cylindrical space. The communication passage enables hydraulic oil to enter the cylindrical space, using fluid pressure to prevent vacuum formation and ensure smooth plunger operation.
2Ease of operation
If hydraulic oil flows out from the pressure chamber through the leakage gap, then damping force is produced for slow plunger movement, but oil consumption increases
Solution Approach 1:
The patent applies the discarding and recovering principle by allowing hydraulic oil to flow out through the leakage gap during the damping phase, then recovering it through the communication passage that allows oil to flow back into the cylindrical space. This creates a recycling mechanism that reduces net oil consumption while maintaining the necessary damping function.
Solution Approach 2:
The communication passage creates a feedback loop where hydraulic oil that has flowed out through the leakage gap can return to the cylindrical space. This feedback mechanism ensures that the system maintains proper oil levels and pressure while minimizing waste, as the oil is continuously recycled rather than being lost.
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 enhances followability to chain slack and reduces oil consumption by ensuring smooth plunger movement and efficient hydraulic oil management, addressing the limitations of existing tensioners.
Implementation Method 1
a return spring biasing the plunger in the direction in which the plunger protrudes out of the cylinder
Implementation Method 2
due to the viscous resistance of the hydraulic oil flowing out from the pressure chamber through the leakage gap, a damping force is produced, allowing the plunger to move slowly
Implementation Method 3
the check valve opens, allowing hydraulic oil to flow through the oil supply passage into the pressure chamber, so that the plunger moves rapidly
Implementation Method 4
when the tension in the chain increases while the engine is running, the plunger moves in the direction in which the plunger is pushed into the cylinder by the tension in the chain
Data Source
AI summary
A chain tensioner includes a sleeve fixedly disposed in a cylinder, with a first end of the sleeve inserted in a plunger and a second end of the sleeve protruding out of the plunger. A cylindrical space is defined between an outer periphery of the sleeve and an inner periphery of the cylinder. An oil supply passage opens to the cylindrical space. A communication passage is defined in the sleeve and provides communication between the cylindrical space and a reservoir chamber.