Pneumatic Tool Direction Switching and Speed Control Mechanism

Solution Overview

Problem

Conventional air tools require high precision and increased manufacturing time and cost due to the need for precise fitting of a valve shaft within a sheath to achieve dual-direction rotation shifting and speed adjusting functions.

Innovation Solution

A rotating direction switching and speed controlling device for air tools that uses a simplified mechanism with a switch knob on the handle, comprising a casing, air cylinder, spring, metal ball, valve cap, and air valve, allowing simultaneous direction and speed control using engineering plastics to reduce weight and cost.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a valve shaft and sheath are used to control rotation direction and speed, then the functions of dual-direction rotation shifting and speed adjusting are achieved, but the manufacturing precision requirement increases and manufacturing time and cost increase

Engineering Contradiction:

Improvedual-direction rotation shifting and speed adjusting functionsVSAvoidprecise fitting of valve shaft within sheath

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent combines the functions of rotation direction switching and speed control into a single integrated switch mechanism. The switch shaft integrates multiple functional features (protrusions, grooves, and positioning structures) that simultaneously control both rotation direction and air inlet opening degree, eliminating the need for separate valve shaft and sheath components and their precise fitting interfaces.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The switch shaft serves multiple functions: it controls rotation direction switching, regulates air inlet opening degree for speed control, and provides positioning through grooves and protrusions. This multi-functional design replaces the specialized valve shaft and sheath assembly, reducing manufacturing precision requirements while maintaining full functionality.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If a valve shaft and sheath are used to control rotation direction and speed, then the functions of dual-direction rotation shifting and speed adjusting are achieved, but the manufacturing time and cost increase

Engineering Contradiction:

Improvedual-direction rotation shifting and speed adjusting functionsVSAvoidmanufacturing time and cost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent combines the functions of rotation direction switching and speed control into a single integrated switch mechanism. The switch shaft integrates multiple functional features (protrusions, grooves, and positioning structures) that simultaneously control both rotation direction and air inlet opening degree, eliminating the need for separate valve shaft and sheath components and their precise fitting interfaces.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent employs engineering plastics for manufacturing the switch shaft and related components instead of metal materials. This substitution significantly reduces manufacturing cost and complexity while maintaining sufficient mechanical strength and functional performance for the application.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Adaptability or versatility

If a valve shaft and sheath are used to control rotation direction and speed, then the functions of dual-direction rotation shifting and speed adjusting are achieved, but the device complexity increases

Engineering Contradiction:

Improvedual-direction rotation shifting and speed adjusting functionsVSAvoidmechanism structure

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines the functions of rotation direction switching and speed control into a single integrated switch mechanism. The switch shaft integrates multiple functional features (protrusions, grooves, and positioning structures) that simultaneously control both rotation direction and air inlet opening degree, eliminating the need for separate valve shaft and sheath components and their precise fitting interfaces.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The switch shaft is designed with segmented functional zones: positioning grooves for direction switching, protrusions for air inlet control, and engagement features for the switch button. This segmentation allows each feature to perform its specific function independently while being integrated into a single compact component, simplifying the overall mechanism.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS8267190B2Direction switching and speed controlling device for a pneumatic tool

Publication Date: 2012.09.18 ZHEJIANG RONGPENG AIR TOOLS CO LTD

AI summary

A direction switching and speed controlling device for an air tool includes two holes provided respectively on two lateral sides of an air cylinder (2). Holes on one side are two air outlets (8), and two holes on another side are a forward rotation air inlet (13) and a reverse rotation air inlet (12). An air valve (7) has an indentation portion (9) provided on a lateral side thereof, the indentation portion (9) is engaged with teeth portion (10) provided on a lower end of a switch (6). At another end, the switch (6) includes an elongated portion (11) provided horizontally with a blind hole (14) provided in the center. A spring (3) is disposed into the hole (14) with a metal ball (4) attached to an end thereof. A valve cap (5) is provided on a bottom portion of a casing (1) with a plurality of spherical grooves (15) provided therein. The metal ball (4) and groove (15) are engaged through the restoration force of the spring (3).