Hydraulic Actuator Speed Control Without Safety Valve Pressure Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dynamic testing systems face inefficiencies due to pressure drops caused by safety valves, which reduce energy efficiency and provide only a single safety layer, limiting the speed of hydraulic actuators and restricting worker access during tests.
Innovation Solution
A method and test station configuration that utilize a flow rate control circuit to manage the flow rate of hydraulic fluid to hydraulic actuators, allowing for controlled reduction of actuator speed through an attenuated differential signal, thereby maintaining safety while minimizing pressure drops and energy inefficiencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an input safety valve is used to limit hydraulic fluid flow rate for safety, then actuator speed is reduced for worker safety, but pressure drops increase and energy efficiency decreases
Solution Approach 1:
The patent removes the traditional input safety valve from the hydraulic system and replaces it with a control system that directly manages actuator speed through flow rate control circuits. This extraction eliminates the pressure drops and energy losses associated with safety valves while maintaining safety through electronic control of the hydraulic actuators.
Solution Approach 2:
The patent replaces the mechanical safety valve with an electronic control system that uses sensors, controllers, and flow rate control circuits to regulate actuator speed. This substitution transitions from a passive mechanical flow restriction to an active electronic control mechanism, eliminating the energy inefficiencies of the valve while preserving safety functionality.
2Speed
If an input safety valve is used to limit hydraulic fluid flow rate, then actuator speed is controlled, but additional pressure drops are introduced in the system
Solution Approach 1:
The patent extracts the safety valve component entirely from the system, replacing its speed-limiting function with an electronic control system. This removal eliminates the pressure drops that would be caused by the valve while maintaining precise actuator speed control through electronic flow rate management.
Solution Approach 2:
The patent changes the control parameter from mechanical flow restriction (valve opening degree) to electronic signal-based flow rate control. By using flow rate control circuits that receive control signals from controllers, the system achieves speed control without the pressure losses inherent in mechanical valve restrictions.
3Reliability
If an input safety valve is used to limit flow rate, then a single safety layer is provided, but system complexity increases
Solution Approach 1:
The patent merges the safety function with the existing control system by integrating flow rate control circuits into the actuator control architecture. Instead of adding a separate safety valve component, the safety functionality is combined with the control valves and controllers already present in the system, reducing overall complexity while maintaining safety.
Solution Approach 2:
The patent makes the control valves and controllers serve dual purposes: normal operation control and safety function. The flow rate control circuits are integrated into the existing control infrastructure, allowing the same components to perform both operational control and safety limiting functions, thereby avoiding additional complexity from dedicated safety 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
The solution effectively limits the speed of hydraulic actuators to ensure safety without introducing additional pressure drops, thereby enhancing energy efficiency and allowing for safer worker access during tests.
Implementation Method 1
The actuators of the test stations are driven by hydraulic fluid flows. The actuations performed by each actuator are controlled using a control valve (e.g., proportional control valve) that regulates the flow rate and direction of the hydraulic fluid flow through the actuator.
Implementation Method 2
Such input safety valves inherently impose pressure drops in the system. These pressure drops must be overcome during normal operation through the higher pressurization of the hydraulic fluid resulting in reduced energy efficiency.
Data Source
AI summary
In a method of controlling a hydraulic actuator of a test station, a differential signal is generated based on a difference between a reference signal and a feedback signal using an actuator controller. A flow rate control circuit is set in one of a first state and a second state based on a flow rate attenuation signal. The differential signal is delivered to the control valve as an actuator command signal when the flow rate control circuit is in the first state. An attenuated differential signal is delivered to the control valve as the actuator command signal when the flow rate control circuit is in the second state. A flow rate and a direction of the hydraulic fluid flow is controlled based on the actuator command signal. The flow rate corresponding to the attenuated differential signal is less than the flow rate corresponding to the differential signal.