Camera Filter Switching Mechanism With Screw And Worm Gear

Solution Overview

Problem

Existing filter-switching mechanisms in camera devices face issues with noise and stability, particularly in open circuit control methods which lack position detection, leading to potential damage and increased noise due to friction-based control.

Innovation Solution

A switching mechanism utilizing a screw thread and worm gear combination with a screw nut and stop blocks to achieve precise positioning and low noise, eliminating the need for complex control units and position-detecting devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If open circuit control methods are used with friction-based control, then the mechanism is simple and low cost, but noise increases and stability deteriorates

Engineering Contradiction:

Improvemechanism simplicityVSAvoidnoise

Core Design Contradiction:

Device complexityVSObject-generated harmful factors

Solution Approach 1:

The patent replaces friction-based mechanical control with a screw thread and worm gear mechanism. The screw thread converts rotational motion to linear motion precisely, while the worm gear provides high speed reduction ratio and self-locking capability, eliminating the need for friction-based positioning and reducing noise significantly.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The worm gear mechanism provides self-locking capability, meaning the driven device cannot reverse-drive the motor. This self-service feature automatically prevents over-travel and damage without requiring external sensors or control systems, maintaining simplicity while improving stability.

Inventive Principle:

Principle #25Self-service

2Device complexity

If open circuit control methods are used without position-detecting devices, then the mechanism is simple and low cost, but reliability deteriorates due to potential damage

Engineering Contradiction:

Improvecontrol unit simplicityVSAvoiddevice stability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The worm gear mechanism provides self-locking capability, meaning the driven device cannot reverse-drive the motor. This self-service feature automatically prevents over-travel and damage without requiring external sensors or control systems, maintaining simplicity while improving stability.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The screw thread and worm gear combination provides inherent mechanical limits to motion. The screw thread defines precise travel distances, and the worm gear's self-locking property prevents reverse motion that could cause damage, acting as a beforehand protective measure against reliability issues.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Device complexity

If friction-based control is used to retain and control movement, then the mechanism is compact and simple, but noise is inevitably produced

Engineering Contradiction:

Improvemechanism simplicityVSAvoidnoise

Core Design Contradiction:

Device complexityVSObject-generated harmful factors

Solution Approach 1:

The patent replaces friction-based mechanical control with a screw thread and worm gear mechanism. The screw thread converts rotational motion to linear motion precisely, while the worm gear provides high speed reduction ratio and self-locking capability, eliminating the need for friction-based positioning and reducing noise significantly.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 provides a stable and low-noise filter-switching mechanism that enhances product quality and competitiveness by ensuring precise positioning and reduced noise, while maintaining a simple and cost-effective design.

Implementation Method 1

The first screw bar is driven by the driving device via a screw thread thereof, and the second screw bar is driven by the first screw bar via a screw thread thereof

Methodology Applied

Scientific EffectScrew thread mechanism: Screw

Implementation Method 2

the relatively stable positioning property, between a screw thread and a screw nut, in conjunction with the high speed reduction ratio of a worm and a worm gear

Methodology Applied

Scientific EffectWorm and worm gear mechanism: Worm Drive

Implementation Method 3

A screw nut is disposed on the lead screw and moved back and forth along the lead screw via the rotation thereof

Methodology Applied

Scientific EffectScrew-nut mechanism: Screw

Data Source

PatentUS7965934B2Switching mechanism for camera device

Publication Date: 2011.06.21 VTC ELECTRONICS CORPORATION

AI summary

A switching mechanism for a camera device includes a driving device, a first screw bar connecting to the driving device, a second screw bar connecting to the first screw bar, and a lead screw having an end coupled with the second screw bar. The first screw bar is driven by the driving device via a screw thread thereof, and the second screw bar is driven by the first screw bar via a screw thread thereof, thereby driving the lead screw for rotation. The screw nut is disposed on the lead screw and moved back and forth via the rotation of the lead screw. Two stop blocks disposed at two ends of the lead screw respectively are to limit two positions of the moved screw nut while the screw nut is moved beyond a threaded area of the lead screw, upon which time the screw nut is slightly engaged with the lead screw.