Vertical Injection Molding Machine Turntable Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Vertical injection molding machines face challenges in maintaining consistent slide resistance and accurate positioning of turntables due to wear and tear, leading to displacement of molds and increased maintenance costs, especially when using stopper pins and complex control systems.
Innovation Solution
A vertical injection molding machine that periodically feeds lubricant to the sliding portions of the turntable to maintain constant slide resistance, combined with a reduction mechanism and encoder system to reset pulse counts at integer revolutions, ensuring accurate positioning without relying on stopper pins.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a stopper pin is used to stop the turntable at predetermined positions, then the turntable can be positioned accurately for mold clamping, but the contact portions of the stopper pin and stopper are worn repeatedly, making it difficult to stop the lower molds at predetermined positions after long period operation
Solution Approach 1:
The patent replaces the mechanical stopper pin and stopper system with a non-contact positioning system using encoders and servo control. The encoder detects the turntable's rotational position electronically, and the servo mechanism adjusts the turntable position based on encoder feedback, eliminating mechanical contact and wear entirely.
Solution Approach 2:
The patent introduces an encoder as an intermediary device between the turntable and the control system. The encoder converts the turntable's mechanical position into electrical signals that can be processed by the control system, enabling precise positioning without direct mechanical contact between stopping components.
2Strength
If the stopper pin is stopped before contact with the stopper, then damage to the drive system is prevented, but the time required from the starting of the revolution of the turntable to the stopping thereof is increased, elongating the overall molding cycle
Solution Approach 1:
The patent implements a feedback control system where the encoder continuously monitors the turntable's position and speed, and the servo mechanism adjusts the drive output in real-time based on this feedback. This allows the turntable to be stopped precisely at the target position without excessive early stopping, reducing unnecessary cycle time while protecting the drive system.
Solution Approach 2:
The patent uses a dynamic control approach where the servo mechanism continuously adjusts the turntable's motion based on real-time encoder feedback. The system can accelerate and decelerate the turntable optimally, stopping precisely at the predetermined position without requiring excessive reduction distance, thereby minimizing cycle time while ensuring accurate positioning.
3Measurement precision
If a complex control system is used to manage the turntable positioning, then accurate positioning can be achieved, but the device complexity increases
Solution Approach 1:
The patent implements a self-correcting positioning system where the encoder automatically detects the turntable's actual position and the servo mechanism automatically adjusts for any deviations. The system self-regulates without requiring complex external control logic, as the feedback loop naturally corrects positioning errors.
Solution Approach 2:
The patent uses a universal servo control system that can manage multiple functions including acceleration, deceleration, positioning, and protection against over-travel. This multi-functional approach consolidates what would otherwise require multiple separate control mechanisms into a single integrated system, reducing overall complexity.
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 machine achieves precise and consistent stopping of the turntable at predetermined positions, reducing maintenance needs and elongating the molding cycle, while allowing for continuous operation with improved production efficiency.
Implementation Method 1
lubricant is fed periodically from a lubricant feeding device to a sliding portion of the revolving turntable to thereby maintain a substantially constant slide resistance of the sliding portion
Implementation Method 2
an encoder for storing the number of revolutions of the servomotor and outputting the number of revolutions of the servomotor as pulses
Data Source
AI summary
The invention provides a vertical injection molding machine capable of periodically feeding lubricant to sliding portions of the turntable to maintain a substantially constant turntable slide resistance and also capable of determining the position of the repeatedly revolving turntable. During operation of a vertical injection molding machine 1, lubricant is periodically fed from a pump 30 to slide portions S of the revolving turntable 14 so as to maintain the slide resistance of the sliding portions S substantially constant. Further, a motor control means 51 resets the count of pulses output from an encoder 29 at a timing at which the number of revolutions of a servomotor 25 and the number of revolutions of the turntable 14 are integers, so that it is possible to prevent pulse errors from accumulating even when the turntable 14 is revolved many times in the same direction.