Adjusting Spool Centering Rate in Pilot-Controlled Hydraulic Valves
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pilot-controlled hydraulic spool valves experience abrupt centering, leading to operator discomfort due to sudden valve closure, causing a 'jumping effect' in hydraulic machinery.
Innovation Solution
An apparatus and system that adjust the rate of spool centering by incorporating hydraulic circuits with controlled-flow and unrestricted-flow conditions, allowing for adjustable spool return speed without limiting movement to left or right positions, using a flow control device with bypass mechanisms to dampen abrupt pilot control pressure changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the spool returns abruptly to center position, then the valve closes quickly and responds rapidly, but this causes a jumping effect in machinery and operator discomfort
Solution Approach 1:
The patent introduces a flow control device as an intermediary between the pilot control system and the main spool valve. This device includes a restricted-flow path and an unrestricted-flow path that mediate the pressure changes, allowing controlled damping of the spool return motion while maintaining system responsiveness
Solution Approach 2:
The patent changes the flow parameters by providing two distinct flow paths with different resistance characteristics. The restricted-flow path limits the rate of pressure change to dampen abrupt movements, while the unrestricted-flow path maintains system responsiveness, effectively controlling the spool centering rate
2Ease of operation
If a flow control device is added to adjust spool centering rate, then operator comfort is improved, but the device complexity increases
Solution Approach 1:
The flow control device is integrated into the existing pilot control hydraulic circuit by merging the restricted-flow and unrestricted-flow paths within the same pilot port structure. This combining approach adds the necessary complexity for comfort control while minimizing additional components and maintaining circuit compactness
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 solution provides a gentle stop for machinery, reduces operator discomfort, and maintains responsiveness, enhancing comfort and productivity while being adaptable for integration with existing hydraulic systems.
Implementation Method 1
a first hydraulic circuit connecting the first pilot port and the first valve port, wherein the first hydraulic circuit, based on a hydraulic fluid pressure of the second pilot port, comprises one of a controlled-flow condition and an unrestricted-flow condition
Implementation Method 2
a second hydraulic circuit connecting the second pilot port and the second valve port, wherein the second hydraulic circuit, based on a hydraulic fluid pressure of the first pilot port, comprises one of a controlled-flow condition and an unrestricted-flow condition
Implementation Method 3
allowing for adjustable spool return speed without limiting movement to left or right positions, using a flow control device with bypass mechanisms to dampen abrupt pilot control pressure changes
Data Source
AI summary
The disclosure is directed to an apparatus and system for adjusting rate of spool centering in a pilot-controlled hydraulic spool valve. The apparatus includes a first pilot port and a second pilot port. The apparatus includes a first valve port and a second valve port. The apparatus also includes a first hydraulic circuit connecting the first pilot port and the first valve port, wherein the first hydraulic circuit, based on a hydraulic fluid pressure of the second pilot port, comprises one of a controlled-flow condition and an unrestricted-flow condition. The apparatus further includes a second hydraulic circuit connecting the second pilot port and the second valve port, wherein the second hydraulic circuit, based on a hydraulic fluid pressure of the first pilot port, comprises one of a controlled-flow condition and an unrestricted-flow condition.