Servo-Driven Redraw Assembly for Low-Wear Can Bodymaking

Solution Overview

Problem

The existing can bodymakers with redraw assemblies actuated by heavy mechanical linkages and cams are prone to wear and tear, requiring more energy than necessary and necessitating an improved actuator for the redraw sleeve to enhance efficiency and durability.

Innovation Solution

A redraw assembly actuated by an eccentric journal assembly coupled with a servomotor, allowing for selectable rotational speeds and precise control of the redraw sleeve's motion through an eccentric journal and connecting rod assembly, enabling efficient and controlled movement between forward and rearward positions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If heavy mechanical linkages and cams are used to actuate the redraw sleeve, then the redraw sleeve can be moved between forward and rearward positions, but the system is prone to wear and tear and requires more energy

Engineering Contradiction:

Improvedurability of redraw assemblyVSAvoidenergy consumption of actuator

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent replaces the traditional heavy mechanical linkage and cam system with an eccentric journal assembly coupled to a servomotor. This substitution eliminates complex mechanical linkages, reducing wear and tear while improving energy efficiency through precise electronic control of the redraw sleeve's reciprocating motion.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The eccentric journal assembly enables precise control of the redraw sleeve's motion parameters (position, speed, dwell time) through rotational eccentricity, allowing optimized energy consumption and reduced mechanical stress compared to traditional cam-based systems.

Inventive Principle:

Principle #35Parameter changes

2Ease of operation

If heavy mechanical linkages and cams are used to actuate the redraw sleeve, then the redraw sleeve can be moved between forward and rearward positions, but the system is complex and prone to wear and tear

Engineering Contradiction:

Improvecontrol of redraw sleeve motionVSAvoidcomplexity of actuator mechanism

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The patent replaces the traditional heavy mechanical linkage and cam system with an eccentric journal assembly coupled to a servomotor. This substitution eliminates complex mechanical linkages, reducing wear and tear while improving energy efficiency through precise electronic control of the redraw sleeve's reciprocating motion.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The eccentric journal assembly serves multiple functions simultaneously: it converts rotational motion to reciprocating linear motion, provides precise positioning control, enables dwell periods at forward position, and reduces mechanical complexity compared to traditional cam and linkage systems.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Speed

If traditional cam-based actuation is used, then the redraw sleeve moves forward and back for each cycle, but the cam must be heavy and consume more energy

Engineering Contradiction:

Improvecycle speed of redraw sleeveVSAvoidenergy loss in actuator

Core Design Contradiction:

SpeedVSLoss of energy

Solution Approach 1:

The eccentric journal assembly enables precise control of the redraw sleeve's motion parameters (position, speed, dwell time) through rotational eccentricity, allowing optimized energy consumption and reduced mechanical stress compared to traditional cam-based systems.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent replaces the traditional heavy mechanical linkage and cam system with an eccentric journal assembly coupled to a servomotor. This substitution eliminates complex mechanical linkages, reducing wear and tear while improving energy efficiency through precise electronic control of the redraw sleeve's reciprocating motion.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 reduces wear and tear, improves energy efficiency, and allows for precise control of the redraw sleeve's motion, enhancing the overall performance and longevity of the can bodymaking process.

Implementation Method 1

a servomotor, which is structured to produce a selectable rotational speed

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

an eccentric journal assembly coupled with a servomotor, allowing for selectable rotational speeds and precise control of the redraw sleeve's motion through an eccentric journal and connecting rod assembly

Methodology Applied

Scientific EffectEccentric mechanism: Eccentric

Data Source

PatentEP3043934B1Redraw assembly comprising a variable speed servo motor

Publication Date: 2024.03.27 STOLLE MACHINERY CO LLC

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AI summary

An actuator for a redraw sleeve that operates independently of the ram drive mechanism is provided. The actuator utilizes an eccentric journal coupled to a drive shaft of a servomotor. The servomotor is structured to provide its output shaft with a variable rotation speed so as to accommodate the need for the redraw sleeve to be in selected locations at specific times. Further, the redraw sleeve includes a collapsing redraw cylinder to allow the redraw sleeve to dwell in a forward position.