Cambered Push Chain Tensioning for Backlash-Free Linear Drives
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional chain racks require high clamping forces and frequent readjustment due to thermal expansion and wear, and they lack a backlash-free mechanism for maintaining precise linear movement.
Innovation Solution
A linear chain is designed with a superelevation that is reduced by a tensioning device, inducing a shear force to create inherent pretension, eliminating the need for traditional tensioning devices and ensuring a backlash-free operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional chain racks use traditional tensioning devices to maintain chain tension, then the chain can be kept taut, but frequent readjustment is required due to thermal expansion and wear elongation
Solution Approach 1:
The chain is pre-formed with a specific camber (superelevation) during manufacturing. This preliminary geometric configuration allows the chain to self-tension when installed in the rack, eliminating the need for frequent readjustment. The camber creates an inherent tensioning effect that compensates for thermal expansion and wear elongation over time.
2Manufacturing precision
If conventional chain racks use high clamping forces to prevent backlash, then positioning precision can be maintained, but the device complexity and required clamping mechanisms increase
Solution Approach 1:
The invention changes the geometric parameter of the chain by introducing a specific camber (superelevation angle). This parameter change transforms the chain from a flat configuration to a three-dimensional arched shape, which inherently resists backlash and maintains positioning precision without requiring complex clamping mechanisms. The cambered geometry itself becomes the precision-maintaining feature.
3Reliability
If the chain is designed with superelevation (camber) to create inherent preload, then backlash-free operation is achieved, but the chain structure becomes more complex
Solution Approach 1:
The chain is given a curved, three-dimensional cambered shape instead of a flat configuration. This curvature (superelevation) creates an inherent preload when the chain is installed in the rack, ensuring backlash-free operation. The curved geometry is formed during manufacturing and becomes an integral part of the chain structure, eliminating the need for additional complexity in the operating mechanism.
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 the superelevation of the linear chain by at least 50%, enhancing the rigidity and synchronization accuracy of the chain rack, allowing for a stable and precise linear drive without the need for continuous readjustment.
Implementation Method 1
The push chain is designed as a cambered push chain with a predetermined camber, whereby the tensioning device reduces the camber of the push chain to induce a tension force in the push chain (the push chain is flattened)
Implementation Method 2
For this reason, it may be easier to determine the camber on a push chain laid on its side. The chain's own weight can act as a tensioning device
Data Source
Figure 1~3
Figure 4
Figure 5~6
AI summary
The present invention relates to a chain rack for a drive with a chain and a tensioning device for tensioning the chain. A push chain is used, wherein a tensioning force is induced in the push chain by means of the tensioning device such that the push chain is subjected to compression in the direction of the rack. Furthermore, the invention relates to a drive with a drive unit and such a chain rack in which the push chain is pre-tensioned against a bearing surface by means of a tensioning force induced by the tensioning device. The invention further relates to the use of a cambered push chain in a chain rack.