Three-Dimensional Stirrup Production via Segmented Bending

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Solution Overview

Problem

Existing methods for producing three-dimensional stirrups require multiple bending operations, leading to high production costs, low productivity, and precision issues, making it difficult to achieve the required geometric characteristics for their application in reinforced concrete construction.

Innovation Solution

An automated method that produces three-dimensional stirrups with only two bending operations by first creating a planar stirrup with parallel legs and then bending the free leg towards the fixed leg, followed by simultaneous out-of-plane bending to create the third dimension, reducing the number of bends required and improving precision.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If multiple bending operations (at least five) are used to produce three-dimensional stirrups with required geometric characteristics, then the precision and quality of the product is improved, but the production time and cost increase significantly

Engineering Contradiction:
Improvegeometric characteristics precisionVSAvoidproduction time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The production process is segmented into two distinct stages: first producing a planar stirrup with parallel legs through two bending operations, then transforming it into a three-dimensional shape by pulling one free leg toward the opposite leg and performing simultaneous out-of-plane bending. This segmentation allows each stage to be optimized independently, reducing the total number of bending operations from five to three while maintaining geometric precision.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The planar stirrup with parallel legs is produced as a preliminary intermediate form before the final three-dimensional shaping. By establishing the correct geometry in the planar stage with only two bendings, the subsequent three-dimensional transformation becomes simpler and requires fewer additional bending operations, thereby reducing total production time while preserving precision.

Inventive Principle:
Principle #10Preliminary action

2Manufacturing precision

If at least five bending operations are performed to achieve the required geometric characteristics, then the product quality is improved, but the production cost increases

Engineering Contradiction:
Improvegeometric characteristics precisionVSAvoidproduction cost
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The manufacturing process is divided into two phases: creating a planar stirrup with parallel legs (requiring only two bendings) followed by three-dimensional transformation (requiring two additional bendings). This segmentation reduces the total bending operations from five to three, directly lowering production costs while maintaining the required geometric precision through optimized process design.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The transformation of the planar stirrup into a three-dimensional shape is achieved by merging multiple actions into simultaneous out-of-plane bending operations. By coordinating the pulling of the free leg and the out-of-plane bending in an integrated manner, the process achieves the desired geometric characteristics with fewer discrete bending operations, reducing both cost and time.

Inventive Principle:
Principle #5Merging (Combining)

3Device complexity

If conventional bending mechanisms are used to produce three-dimensional stirrups, then the production process is simplified, but the productivity remains low

Engineering Contradiction:
Improvebending mechanism complexityVSAvoidproduction productivity
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The planar stirrup with parallel legs is produced first as a prepared intermediate form, which simplifies the subsequent three-dimensional transformation. This preliminary action allows the final shaping to be accomplished more efficiently with fewer bending operations, thereby increasing productivity without requiring overly complex bending mechanisms.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The process transitions from two-dimensional planar bending to three-dimensional out-of-plane bending in a coordinated manner. By establishing the correct planar geometry first and then adding the third dimension through simultaneous bending operations, the system achieves higher productivity while keeping the bending mechanism complexity manageable.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

4Manufacturing precision

If five or more bending operations are performed, then the geometric characteristics are achieved, but the energy consumption increases

Engineering Contradiction:
Improvegeometric characteristics precisionVSAvoidenergy consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The bending operations are segmented into two phases: planar bending (two operations) and three-dimensional transformation (two additional operations). This segmentation reduces the total number of bending operations from five to three, directly lowering energy consumption while maintaining geometric precision through optimized process design.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The pulling of the free leg and the out-of-plane bending operations are merged into a coordinated process that achieves three-dimensional shaping with fewer discrete bending operations. This merging reduces the cumulative energy consumption associated with multiple separate bending cycles while maintaining the required geometric characteristics.

Inventive Principle:
Principle #5Merging (Combining)

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 approach significantly reduces production time and costs, enhances product quality and precision, and simplifies placement in metallic cases, resulting in efficient and cost-effective production of three-dimensional stirrups with improved geometric characteristics.

Implementation Method 1

the free leg 5 is trapped at a suitable location 11 and is pulled towards the opposite leg 4

Methodology Applied
Scientific EffectMechanical Force: Mechanical Force

Implementation Method 2

bending simultaneously at suitable locations 12,13 the stirrup out of the plane, so as to create a third dimension

Methodology Applied
Scientific EffectDeformation: Deformation

Data Source

PatentEP1852195B1Method and Machine for Production of Three-Dimensional Stirrups
Publication Date: 2010.08.18 ANAGNOSTOPOULOS ANTONIOS
  • EP1852195B1 patent drawingFigure 1~2
  • EP1852195B1 patent drawingFigure 3~4
  • EP1852195B1 patent drawingFigure 5~6

AI summary

Method and machine for production of three-dimensional stirrups (1a) with two converging legs (4,5), from rods, wire or other material of any cross-section, wherein first is produced with the aid of a bending head (19) by making two bending operations a planar stirrup (9) with parallel legs. Afterwards, utilizing a mechanism (25) located immediately following this bending head (19), which mechanism includes an arm (16) that may move in reciprocation with the aid of a suitable mechanism (18) and has a hook (17) at its end, the free leg (5) of the planar stirrup (9) is trapped by the hook (17). This trapped free leg (5) is pulled towards the opposite leg (4) as arm (16) reciprocates, covering an appropriate distance. Finally, the third dimension is generated by bending simultaneously at locations (12, 13) with a suitable bending mechanism (22) that is located after the mechanism (25).