Continuously Operating Press Frame Asymmetry

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing wood-based material and plastic panel presses face challenges in maintaining a consistent press gap due to the widening and narrowing of the gap between hydraulic cylinder application points, leading to undesirable quality issues, especially in thin chipboard or hardboard, and require complex and costly constructions with multiple components.

Innovation Solution

A continuously operating press with separate upper and lower yokes connected via tie rods and hydraulic cylinders arranged transverse to the belt direction, allowing for uniform pressure distribution and adjustable press gap without the need for bridge elements, facilitating easier assembly and maintenance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the press gap is adjusted between adjacent application points, then the pressing force can be applied uniformly, but the press gap widens and narrows causing glue bridges to break open

Engineering Contradiction:
Improvepress gap consistencyVSAvoidglue bridge integrity
Core Design Contradiction:
Manufacturing precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent applies asymmetry by offsetting the lower yoke plates relative to the upper yoke plates in the longitudinal direction. This creates an asymmetric configuration where the abutment points on the lower heating plate are shifted relative to the application points on the upper heating plate, preventing the press gap from widening and narrowing between adjacent application points.

Inventive Principle:
Principle #4Asymmetry

2Force

If bridge elements are used to connect adjacent press frames, then the pressing force can be transferred, but the assembly and maintenance become difficult and expensive

Engineering Contradiction:
Improvepressing force transferVSAvoidnumber of components
Core Design Contradiction:
ForceVSDevice complexity

Solution Approach 1:

The patent merges the function of bridge elements into the tie rod system. The tie rods serve dual purposes: connecting adjacent press frames and transferring pressing forces. This eliminates the need for separate bridge elements, reducing component count and simplifying assembly and maintenance.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The tie rods are designed to perform multiple functions: structural connection between press frames, force transfer from heating plates, and enabling press gap adjustment. This multi-functionality replaces the need for dedicated bridge elements and simplifies the overall press frame construction.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Force

If hydraulic cylinders are positioned between upper yoke and tie rods, then the press frame can be pressed down as a whole, but different compressive forces cannot be applied across the width

Engineering Contradiction:
Improvecompressive force applicationVSAvoidpressure distribution control
Core Design Contradiction:
ForceVSAdaptability or versatility

Solution Approach 1:

The patent applies local quality by positioning hydraulic cylinders between the upper heating plate and upper yoke at specific locations. This allows different compressive forces to be applied at different positions across the width of the heating plate, enabling compensation for thermal stresses and deformations in specific areas rather than uniform pressing.

Inventive Principle:
Principle #3Local quality

4Manufacturing precision

If different widths of lower yokes are used, then different distances between abutments can be created, but different press frames must be provided increasing costs

Engineering Contradiction:
Improveabutment distance variationVSAvoidpress frame standardization
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent applies dynamics by making the lower yoke configuration adjustable rather than fixed. The lower yoke plates can be positioned at different offsets relative to the upper yoke plates, allowing the abutment distance to be varied without requiring completely different press frames. This dynamic adjustability maintains standardization while achieving the desired press gap control.

Inventive Principle:
Principle #15Dynamics

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 design simplifies assembly and maintenance, reduces component complexity and costs, and enables uniform pressure application across the press width, ensuring a consistent press gap and improved product quality.

Implementation Method 1

the application point of the pressing forces via the hydraulic cylinders on the upper heating platen and the corresponding position of the abutments absorbing these pressing forces on the lower heating platen

Methodology Applied
Scientific EffectHydraulic press: Hydraulic Press

Implementation Method 2

previously glued particles are processed into panels under the action of pressure and heat, the heat being particularly relevant for the setting reaction of the glue used

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP3294540B1Continuously operating press
Publication Date: 2019.08.14 DIEFFENBACHER GMBH MASCH UND ANLAGENBAU
  • EP3294540B1 patent drawingFigure 1
  • EP3294540B1 patent drawingFigure 2

AI summary

The invention relates to a continuously operating press for producing wood-based boards or plastic sheets, in particular fibreboards or particle boards, comprising a press frame with multiple press frames having respective upper yokes (1) and lower yokes (2) and arranged one behind the other in the longitudinal direction of the press, said press frames surrounding heating plates (10, 16) running in the press longitudinal direction, and comprising flexible continuous steel belts (12, 13) which draw the material to be pressed (14) through the press and which are guided via drive pulleys and deflection rollers around the plurality of upper yokes (1) and lower yokes (2) and which are supported against the heating plates (10, 16) via co-rotating rolling support elements (11, 15) guided with the axes thereof transverse to the belt running direction (18), wherein the press nip lying between the steel belts (12, 13) is adjustable via a plurality of hydraulic cylinders (9) arranged transverse to the belt running direction (18) and respectively adjacent to one another between the upper yokes (1) and the upper heating plate (10), and wherein the lower heating plates (16) are supported against the pressure applied by the hydraulic cylinder (9) on the lower yoke (2). According to the invention, in order to be able to carry out a desired bevel function of the heating plates (10, 16) even under load, the press frames are each formed by upper yokes (1) and lower yokes (2) connected to one another by tie rods (3), wherein the lower yokes (2) are each formed by two parallel plates (21, 22) which are each arranged on both sides outside of the elements (23, 24) of the tie rods (3).