Lead Screw Window Operator Using Composite Plastic

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lead screw operators for windows are typically made of metal to withstand stresses, leading to higher costs and issues with longitudinal movement affecting the connection between the lead screw and its gear, particularly when the lead screw moves.

Innovation Solution

A lead screw window operator design that uses a non-metallic material, such as plastic, with a lead screw support structure and collars that maintain tension and prevent rotation, allowing for a sliding fit with a gear to manage longitudinal movement and stresses.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the lead screw operator is made of metal to withstand stresses, then the strength and reliability are improved, but the manufacturing cost increases

Engineering Contradiction:

ImprovestrengthVSAvoidmanufacturing cost

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent changes the material parameter from metal to plastic, and more specifically to a composite plastic material containing fiberglass reinforcement. This parameter change allows the material to achieve sufficient strength and stiffness to withstand the operational stresses of the lead screw operator while being more cost-effective and easier to manufacture than traditional metal materials.

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If the lead screw is made of plastic to reduce cost, then the manufacturing cost decreases, but the reliability and ability to withstand stresses deteriorates

Engineering Contradiction:

Improvemanufacturing costVSAvoidreliability

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent employs composite materials, specifically a plastic material reinforced with fiberglass strands or continuous fibers. This composite structure combines the cost-effectiveness and ease of manufacturing of plastic with the enhanced strength, stiffness, and reliability of fiberglass reinforcement, thereby achieving both economic and performance objectives.

Inventive Principle:

Principle #40Composite materials

3Adaptability or versatility

If the lead screw has longitudinal movement for manufacturing tolerances, then the adaptability is improved, but the connection stability between the lead screw and gear deteriorates

Engineering Contradiction:

ImproveadaptabilityVSAvoidconnection stability

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent introduces a collar as an intermediary component between the lead screw and the gear. This collar serves as a mediator that maintains the connection stability despite longitudinal movement of the lead screw. The collar is positioned to engage with both the lead screw and the gear, ensuring that the gear remains properly positioned relative to the lead screw even when the lead screw moves longitudinally to accommodate manufacturing tolerances.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS8365470B1Lead screw operator

Publication Date: 2013.02.05 CAMPBELL FR W

AI summary

A lead screw window operator (100) utilizes a lead screw (110) that is in tension whether the operator is being used to open or close a window assembly (10). The lead screw window operator (100) may include a nut (170) that has edges sufficiently close to first and second support surfaces to prevent excess rotation of the nut (170). Also, the lead screw (110) may have a splined end to operatively connect to a first gear that has a splined profile to allow the gear to slide along the lead screw along a longitudinal axis.