Hydraulic Control System Pressure Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydraulic working devices experience hunting oscillations or abruptly shaking due to abrupt changes in discharge pressure at low temperatures, which existing hydraulic control systems fail to prevent effectively.
Innovation Solution
A hydraulic control system that includes a pump discharge pressure detector, a comparator, and a calculator to recognize and adjust the control pressure based on a pre-stored lowest recognition pressure value, preventing resonance and vibrations in the variable displacement hydraulic pump.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If constant horsepower control is implemented by adjusting pump displacement based on discharge pressure, then engine and system protection is achieved, but hunting oscillations and abrupt shaking occur in low-temperature environments due to abrupt pressure changes
Solution Approach 1:
The patent introduces a dead zone parameter (pressure range between lower and upper threshold values) within which control signals are not generated. This parameter change prevents the control system from responding to normal pressure fluctuations, thereby eliminating hunting oscillations while maintaining protection against abnormal pressure conditions
Solution Approach 2:
The patent introduces threshold values as intermediary parameters that mediate between the discharge pressure sensor and the control signal generator. These threshold values act as a buffer, filtering out minor pressure variations while allowing significant pressure changes to trigger appropriate control actions
2Power
If the hydraulic controller transmits control signals for displacement adjustment in response to abrupt pressure changes, then constant horsepower is maintained, but resonance occurs causing pump discharge pressure vibrations
Solution Approach 1:
The patent applies preliminary anti-action by establishing threshold criteria before control signals are generated. When pressure changes fall within the dead zone, no control signal is transmitted, preventing the system from entering a resonant state. This preemptive filtering avoids the harmful vibrations before they can occur
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The present invention provides a hydraulic control system comprising: a flow rate control valve; a variable displacement hydraulic pump which is connected to the flow rate control valve and discharges hydraulic pressure to the flow rate control valve; a pump discharge pressure detector which is installed in a section where the flow rate control valve and the variable displacement hydraulic pump are connected, and detects the discharge pressure of the hydraulic pressure discharged from the variable displacement hydraulic pump to the flow rate control valve; and a hydraulic controller comprising a detection unit which is connected to the pump discharge pressure detector, detects the discharge pressure of the variable displacement hydraulic pump and converts the discharge pressure to a pump discharge pressure value, a comparison unit which receives the pump discharge pressure value from the detection unit, compares the pump discharge pressure value with a pre-stored lowest recognition pressure value, and determines whether the pump discharge pressure value is greater or less than the lowest recognition pressure value, and a calculation unit which, by interworking with the comparison unit, if the pump discharge pressure value is less than the lowest recognition pressure value, calculates a control pressure by recognizing the control pressure of the variable displacement hydraulic pump as the lowest recognition pressure value.