Planetary Transmission Layout for 28-Speed Compact Commercial Vehicles

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing agricultural and industrial commercial vehicle transmissions require excessive installation space due to numerous shafts and gear sets, leading to insufficient gear ratios, high complexity, and increased production costs, while also lacking optimal compactness and efficiency.

Innovation Solution

A transmission system featuring a primary transmission unit with multiple planetary gear sets, an intermediate gearbox, and a reversing unit, which includes shifting elements like clutches and brakes, allowing for a wide range of gear combinations to achieve up to 28 forward and 28 reverse gears, optimizing space and reducing complexity through a compact, modular design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If traditional power shift transmissions are used with multiple shafts and gear sets, then a sufficient number of gear ratios can be achieved, but the installation space requirement increases excessively

Engineering Contradiction:

Improvenumber of gear ratiosVSAvoidinstallation space

Core Design Contradiction:

Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The patent merges multiple traditional shaft-based gear sets into a single planetary gear set where multiple sun gears share common planet gears and ring gears. This consolidation achieves the same gear ratio multiplication effect while dramatically reducing the spatial footprint required for the transmission system.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The planetary gear set employs a nested structure where planet gears are positioned between sun gears and ring gears, with multiple planetary stages sharing common components. This nested arrangement allows multiple gear reduction stages to be compactly integrated within a single transmission housing, minimizing installation space.

Inventive Principle:

Principle #7Nested doll (Nesting)

2Adaptability or versatility

If traditional transmissions with many shafts and gear sets are used, then gear ratio coverage is improved, but the device complexity increases

Engineering Contradiction:

Improvegear ratio coverageVSAvoidtransmission complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines the functions of multiple independent shafts and gear sets into a single integrated planetary gear system. By sharing common planet gears, ring gears, and clutch mechanisms across multiple sun gears, the design achieves comprehensive gear ratio coverage while reducing the number of discrete components and simplifying the overall transmission architecture.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The common planet set and ring gear serve multiple functions simultaneously, engaging with different sun gears to provide various gear ratios. This multi-functional design eliminates the need for separate dedicated gear sets for each ratio, thereby reducing device complexity while maintaining versatile gear coverage.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If traditional transmissions with numerous shifting elements are used, then sufficient gear ratios are achieved, but production costs increase

Engineering Contradiction:

Improvenumber of gearsVSAvoidproduction costs

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent consolidates multiple shifting elements into a unified control system where a single clutch mechanism can engage or disengage different sun gears from the common planet set. This merging of shifting functions reduces the total number of clutches, brakes, and synchronizers required, thereby lowering manufacturing costs while maintaining the capability to achieve multiple gear ratios.

Inventive Principle:

Principle #5Merging (Combining)

4Area of stationary object

If compact transmission design is implemented with planetary gear sets, then installation space is reduced, but torque transmission capability must be maintained

Engineering Contradiction:

Improveinstallation spaceVSAvoidtorque transmission

Core Design Contradiction:

Area of stationary objectVSForce

Solution Approach 1:

The planetary gear set utilizes a nested configuration where planet gears are positioned radially between sun gears and ring gears, creating efficient torque transmission paths through multiple contact points. This nested structure maximizes the torque capacity within a compact radial footprint, maintaining high force transmission capability while minimizing installation space.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The planetary gear mechanism employs curved tooth profiles and radial force distribution across multiple planet gears simultaneously engaging with sun and ring gears. This geometric arrangement distributes torque loads evenly across multiple contact surfaces, enabling high torque transmission through a compact design without requiring excessive space.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentUS11879527B2Transmission and agricultural or industrial commercial vehicle

Publication Date: 2024.01.23 DEERE & CO

AI summary

A transmission includes a drive element, a first output element, a primary transmission unit, a reversing unit, and an intermediate gearbox. At least two of the at least nine shifting elements of the primary transmission unit, at least one of the at least two shifting elements of the reversing unit, and at least one of the at least two shifting elements of the intermediate gearbox are activatable in combinations of at least four shifting elements so as to establish at least twenty-eight forward gears between the drive element and the first output element.