Hybrid Drive System Using Braking Device to Lock Combustion Engine

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional hybrid vehicle drive systems face issues with noise, exhaust emissions, and increased fuel consumption, particularly in low-load conditions, and suffer from energy losses due to the use of friction clutches and heavy, costly clutch mechanisms.

Innovation Solution

A method and drive system that utilize a braking device to keep the combustion engine inactive, allowing the electrical machine to operate exclusively, with the planetary gear configured to provide higher torque and reduce energy losses by locking the combustion engine in a standing state, thus avoiding rotation with the electrical machine and minimizing wear on the planet wheel carrier.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a conventional clutch mechanism is used to disconnect the input shaft of the gearbox from the combustion engine during gear change, then the gear changing function is achieved, but the fuel consumption increases and the clutch discs wear due to heating

Engineering Contradiction:

Improvegear changing functionVSAvoidfuel consumption

Core Design Contradiction:

Ease of operationVSUse of energy by moving object

Solution Approach 1:

The invention extracts and removes the conventional clutch mechanism from the drivetrain, replacing it with a planetary gear system that achieves gear changing without the need for friction-based clutch engagement. This eliminates the harmful heating and energy loss associated with conventional clutch operation.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces the friction-based mechanical clutch system with a planetary gear mechanism that uses mechanical locking and releasing of gear elements to achieve gear changes. This substitution eliminates the sliding friction and heat generation inherent in conventional clutch designs.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

Engineering Contradiction:

Improvegear changing functionVSAvoidclutch mechanism weight

Core Design Contradiction:

Ease of operationVSWeight of moving object

Solution Approach 1:

The invention removes the heavy conventional clutch mechanism entirely from the drivetrain, replacing it with a more compact planetary gear system that achieves the same gear changing function with significantly reduced weight and cost.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention merges the gear changing function with the planetary gear mechanism, combining multiple functions into a single integrated system rather than using separate clutch and gear change mechanisms. This integration reduces overall system weight and complexity.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If the combustion engine and electrical machine are controlled based on main operational conditions to maintain battery charge level, then the battery charge is maintained, but noise and exhaust gases are released in situations where they are not permitted

Engineering Contradiction:

Improvebattery charge levelVSAvoidnoise and exhaust gases

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The invention implements dynamic control of the drivetrain components, allowing the planetary gear and braking device to be adjusted in real-time based on operational requirements. This enables the system to switch between different operational modes, including a quiet mode where the combustion engine is locked and only the electrical machine operates.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes the operational parameters of the drivetrain by locking the combustion engine using the braking device and disengaging the planetary gear, thereby switching from a combustion-driven mode to an electric-only mode. This parameter change eliminates noise and exhaust emissions while maintaining vehicle operation.

Inventive Principle:

Principle #35Parameter changes

4Loss of energy

If the planetary gear is configured to lock the combustion engine in a standing state, then energy losses are reduced and the electrical machine can operate exclusively, but the device complexity increases

Engineering Contradiction:

Improveenergy lossesVSAvoidplanetary gear configuration

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The planetary gear mechanism in the invention serves multiple functions: it enables gear changing, allows the combustion engine to be locked in a standing state, and facilitates the electrical machine to operate exclusively when needed. This multi-functionality reduces the need for additional separate mechanisms, thereby limiting the increase in device complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The planetary gear acts as an intermediary mechanism between the combustion engine and the electrical machine, allowing smooth transitions between different operational modes. It mediates the power flow and enables the combustion engine to be locked without requiring complex additional locking mechanisms.

Inventive Principle:

Principle #24Intermediary (Mediator)

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

Enables quieter operation with reduced exhaust emissions, lower energy losses, and lower fuel consumption by allowing the electrical machine to operate in its maximum power range, while preventing damage to the combustion engine and reducing wear on the drivetrain components.

Implementation Method 1

The planetary gear that comprises a sun gear, a ring gear and a planet wheel carrier... the output shaft of the combustion engine is connected with a first of said components of the planetary gear so that they rotate as a unit with a first speed of rotation... the input shaft of the gearbox is connected with a second of said components of the planetary gear so that they rotate as a unit with a second speed of rotation

Methodology Applied

Scientific EffectMechanical Advantage: Mechanical Advantage

Implementation Method 2

an electrical machine that comprises a stator and a rotor... controlling the electrical machine so that it provides a third component of the planetary gear with a speed of rotation

Methodology Applied

Scientific EffectElectromagnetic Induction: Electromagnetic Induction

Data Source

PatentEP2867088B1Method for controlling a drive system of a vehicle, a drive system, a computer program, a computer program product and a vehicle

Publication Date: 2020.08.05 SCANIA CV AB

Figure 1a~1b
Figure 2
Figure 3

AI summary

Method for controlling a drive system of a vehicle. The drive system comprises a combustion engine (2) with an output shaft (2a), a gearbox (3) with an input shaft (3a), an electrical machine (9) that comprises a stator (9a) and a rotor (9b), and a planetary gear that comprises a sun gear (10), a ring gear (11) and a planet wheel carrier (12). The combustion engine comprises an active state and an inactive state. The drive system comprises a breaking device (28) comprising an active state and passive state. The planetary gear comprises a released state and a locked state. The method comprises arranging the planetary gear in the released state, the combustion engine in the inactive state, the braking device in the active state, and information on a requested torque for the operation of the vehicle is received, wherein the electrical machine is controlled so that the requested torque is provided while maintaining the combustion engine in the inactive state, the braking device in the active state and the planetary gear in the released state.