Shovel Turning Body Inversion Braking via Solenoid Valves
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Construction machines with turning bodies face challenges in immediately stopping the turning operation due to large moments of inertia, leading to potential collisions with entering objects.
Innovation Solution
The implementation of a control method that uses solenoid proportional valves to rapidly switch the flow of operating oil to the turning hydraulic motor, applying a braking force in the opposite direction of the turning direction, allowing for quicker stopping of the turning operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the supply of operating oil to the turning hydraulic motor is shut off to stop the turning operation, then the turning operation stops, but the large moment of inertia of the attachment causes the turning body to be difficult to make an immediate stop
Solution Approach 1:
Instead of simply shutting off the oil supply to stop the turning hydraulic motor, the invention applies reverse oil supply to the motor. By supplying oil to the opposite port of the hydraulic motor, a braking force is generated in the opposite direction of the turning motion, enabling the turning body to stop immediately despite the large moment of inertia of the attachment.
2Reliability
If the turning operation is stopped by shutting off operating oil supply, then the turning body stops, but the large moment of inertia causes delayed stopping leading to potential contact with entering objects
Solution Approach 1:
The control device switches the oil supply to the opposite port of the turning hydraulic motor when an entering object is detected. This reverse oil supply generates an immediate braking force in the opposite direction, allowing the turning body to stop quickly and reliably avoid collisions with entering objects.
Solution Approach 2:
The control device continuously monitors the turning operation and detects entering objects in the turning range. When an entering object is detected, the control device immediately changes the oil supply direction to generate braking force, creating a feedback control loop that ensures reliable collision avoidance.
3Loss of time
If solenoid proportional valves are used to rapidly switch oil flow to generate braking force, then the braking distance is reduced, but the device complexity increases
Solution Approach 1:
The invention uses solenoid proportional valves to control the hydraulic oil flow to the turning hydraulic motor. By rapidly switching the oil flow direction using these valves, a large braking force is generated immediately, significantly reducing the braking distance despite the complexity added by the valves.
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 solution effectively reduces the braking distance and ensures the shovel can avoid collisions with entering objects by generating a large braking force, even when the operator's lever operation is affected by vibrations.
Implementation Method 1
a control method that uses solenoid proportional valves to rapidly switch the flow of operating oil to the turning hydraulic motor, applying a braking force in the opposite direction of the turning direction
Implementation Method 2
it is difficult for the above-mentioned shovel to stop the turning body immediately after shutting off the supply of operating oil to the turning hydraulic motor due to a moment of inertia. This is because an attachment having a large moment of inertia is attached to the turning body of the shovel
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A shovel includes a lower running body and an upper turning body that is turnably provided on the lower running body. An engine is mounted on the upper turning body. A hydraulic pump is driven by the engine to discharge an operating oil. A hydraulic actuator is mounted on the upper turning body. A control device controls operations of the shovel. An entering object detection device detects a position of an entering object in a monitoring area of said shovel and outputs a detection signal indicating the detection position of said entering object. The control device supplies, after a determination of an entry of the entering object into the monitoring area, the operating oil from the hydraulic pump to the hydraulic actuator.