Linear Guide Holder Plate Warping Correction

Solution Overview

Problem

The existing side seals in linear guide devices, which combine a seal member, holder plate, and cover, often suffer from manufacturing errors like warping of the holder plate made of hard resin, leading to gaps and compromised sealing performance due to contraction deformation during injection molding, especially when multiple seals are overlapped.

Innovation Solution

The linear guide device incorporates a holder plate with a thickness retention portion and a thin portion to correct warping and prevent gaps, using materials like polyacetal resin and soft resins for the holder plate and lip portion respectively, and a cover made of hard materials to ensure effective sealing by blocking foreign matter and maintaining sealing performance even with manufacturing errors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the holder plate is made of hard resin and manufactured by injection molding, then the ease of manufacture is improved, but the holder plate warps due to contraction deformation, leading to gaps and degraded sealing performance

Engineering Contradiction:

Improveease of manufactureVSAvoidmanufacturing precision

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent changes the physical parameters of the holder plate by introducing a thin portion with reduced thickness and lower rigidity compared to the base portion. This parameter change allows the holder plate to flex and correct warping deformations that occur during injection molding, thereby maintaining sealing contact without compromising the ease of manufacture through injection molding processes.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies local quality by creating a thin portion with different thickness and rigidity characteristics at a specific location of the holder plate, while the base portion maintains its original thickness and strength. This localized modification enables the holder plate to accommodate warping while preserving overall structural integrity and manufacturability.

Inventive Principle:

Principle #3Local quality

2Reliability

If multiple seals are overlapped to improve sealing performance, then the sealing function is enhanced, but gaps are more easily formed between the seals due to warps of the holder plates

Engineering Contradiction:

Improvesealing functionVSAvoidgap formation

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The thin portion design allows each holder plate in the overlapping seal arrangement to flex independently, correcting its own warping deformations. This parameter change ensures that even when multiple seals are overlapped, each seal maintains proper contact with the guide rail without forming gaps between them, thereby enhancing sealing reliability.

Inventive Principle:

Principle #35Parameter changes

3Weight of moving object

If the holder plate is made thinner to reduce weight, then the weight of the moving object is reduced, but the rigidity decreases, making the holder plate more susceptible to warping

Engineering Contradiction:

ImproveweightVSAvoidrigidity

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The patent applies local quality by creating a thin portion with different thickness and rigidity characteristics at a specific location of the holder plate, while the base portion maintains its original thickness and strength. This localized modification enables the holder plate to accommodate warping while preserving overall structural integrity and manufacturability.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the physical parameters of the holder plate by introducing a thin portion with reduced thickness and lower rigidity compared to the base portion. This parameter change allows the holder plate to flex and correct warping deformations that occur during injection molding, thereby maintaining sealing contact without compromising the ease of manufacture through injection molding processes.

Inventive Principle:

Principle #35Parameter changes

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 solution effectively corrects warping and maintains the seal function of the side seal, preventing foreign matter entry and lubricant leakage, enhancing sealing performance by using a combination of materials and structural features that manage fastening torque and prevent damage to the lip portion.

Implementation Method 1

a thin portion (3d) that is thinner and has a lower rigidity than the thickness retention portion (3a, 3b)... the warp of the holder plate may form a gap between the slider and the side seal

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Implementation Method 2

a side seal having a lip portion in sliding contact with on the guide rail... prevents foreign matter from entering the inside of the slider

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentUS9482273B2Linear guide device

Publication Date: 2016.11.01 NSK LTD

AI summary

A side seal included in a linear guide device of the present disclosure has one or a plurality of seals, and the seals each have a lip portion, and a holder plate made of hard resin configured to the lip portion and to be mounted on a slider. The holder plate has a thickness retention portion configured to retain plate thickness, and a thin portion that is thinner than and has a lower rigidity than the thickness retention portion. The thickness retention portion is formed along at least the portion of an outer edge of the holder plate where there is not the portion. The thin portion is blocked by the thickness retention portion from the outside.