Programmable Controller Cycle Time Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional programmable controllers require significant time and effort to optimize the fixed cycle time, as they need to repeatedly switch between operating and stop states to adjust the cycle time, which affects the throughput and responsiveness of control target devices.
Innovation Solution
A programmable controller with an integrated system memory, user memory, and input/output memory that allows for real-time measurement and adjustment of cycle times, enabling the optimization of fixed cycle time during operation without the need to switch states, using a time adjustment process that compares actual and fixed cycle times and adjusts accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the programmable controller repeatedly switches between operating and stop states to adjust fixed cycle time, then the cycle time optimization is achieved, but the time loss and productivity are significantly reduced
Solution Approach 1:
The patent applies preliminary action by measuring the actual cycle time during the current operating state and using this measurement to determine the optimal fixed cycle time before making adjustments. This allows the controller to optimize cycle time parameters without needing to switch to stop state, as the necessary measurements and calculations are performed in advance during normal operation.
Solution Approach 2:
The patent maintains continuity of useful action by allowing the programmable controller to continue executing the user program and performing input/output refresh processes while the cycle time optimization is being performed. The controller continuously measures actual cycle time and adjusts fixed cycle time settings without interrupting the operational flow, thereby eliminating the need to switch between operating and stop states.
2Manufacturing precision
If the programmable controller switches to stop state for cycle time adjustment, then the fixed cycle time can be optimized, but the productivity and throughput are reduced
Solution Approach 1:
The system performs preliminary measurement of actual cycle time during operation and calculates the optimal fixed cycle time before any adjustment is made. This preliminary action during the operating state eliminates the need to stop production for optimization, thereby maintaining productivity while achieving precise cycle time settings.
Solution Approach 2:
The optimization process continues to operate usefully by measuring actual cycle time and adjusting fixed cycle time settings without interrupting the user program execution or input/output refresh processes. The control target device maintains continuous throughput while the programmable controller optimizes timing parameters in the background.
3Stability of the object's composition
If the fixed cycle time is set to a value higher than actual cycle time, then the cycle time can be stabilized, but the waiting time increases
Solution Approach 1:
The patent implements feedback by continuously measuring the actual cycle time during operation and using this measurement to determine the appropriate fixed cycle time setting. This feedback mechanism ensures that the fixed cycle time is set as close as possible to the actual cycle time, stabilizing the timing while minimizing unnecessary waiting time that would result from overly conservative high-value settings.
Data Source
AI summary
The value of fixed cycle time is adjusted to an optimum value in a short period of time. In a second operational mode (MON) of a PLC, a series of a plurality of system processes are repeatedly performed with a change to a user program in a peripheral service process being allowed. A change to fixed cycle time to be compared with actual cycle time is prohibited in a first operational mode (RUN) but is allowed in the second operational mode (MON) and a non-operational mode (PRG).