Power Tool Switching Unit for Compact Multi-Mode Gear Control

Solution Overview

Problem

Existing machine tool devices with drive train units that include gear shift elements for rotational direction and speed modes are complex and require multiple mechanical components for switching, making them bulky, expensive, and unreliable.

Innovation Solution

A machine tool device with a switching unit that includes an actuating element and a switching element, allowing for electronic and automatic switching between rotational direction modes and speed modes, reducing the need for complex mechanical components and enabling a compact, inexpensive, and reliable design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple mechanical components are used for switching between rotational direction modes and speed modes, then the machine tool device can achieve mode switching functionality, but the device becomes bulky, expensive, and unreliable

Engineering Contradiction:

Improvemode switching functionalityVSAvoidnumber of mechanical components

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical switching components with an electronic control system. The electronic control unit receives switching signals and automatically controls the motor to change rotational direction and speed modes, eliminating the need for multiple mechanical switches and gear shift elements.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The electronic control unit serves multiple functions: it controls both rotational direction switching and speed mode switching, and also manages motor activation. This multi-functionality consolidates what would traditionally require separate mechanical components into a single electronic control system.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If multiple mechanical components are used for switching between rotational direction modes and speed modes, then the machine tool device can achieve mode switching functionality, but the device becomes more expensive

Engineering Contradiction:

Improvemode switching functionalityVSAvoidmanufacturing cost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent replaces complex mechanical switching components with an electronic control system. The electronic control unit receives switching signals and automatically controls the motor to change rotational direction and speed modes, eliminating the need for multiple mechanical switches and gear shift elements.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Adaptability or versatility

If multiple mechanical components are used for switching between rotational direction modes and speed modes, then the machine tool device can achieve mode switching functionality, but the device becomes less reliable

Engineering Contradiction:

Improvemode switching functionalityVSAvoidswitching reliability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent replaces complex mechanical switching components with an electronic control system. The electronic control unit receives switching signals and automatically controls the motor to change rotational direction and speed modes, eliminating the need for multiple mechanical switches and gear shift elements.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP3787841B1Power tool device

Publication Date: 2023.06.07 ROBERT BOSCH GMBH

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AI summary

The invention proceeds from a power tool device, comprising at least one drive train unit (12a; 12b), which comprises at least one gear shifting element (14a; 14b) and has at least two different direction-of-rotation modes and at least two different speed modes, and comprising at least one switching unit (16a; 16b), which is arranged at least partially on the drive train unit (12a; 12b). According to the invention, the switching unit (16a; 16b) comprises at least one actuation element (18a; 18b) for selecting the direction-of-rotation modes and the speed modes and at least one switching element (20a; 20b) for switching between the direction-of-rotation modes in dependence on the switching position of the actuation element (18a; 18b).