Shift Range Switching Apparatus Motor Current Control

Solution Overview

Problem

The existing shift range switching systems for automatic transmissions in vehicles with shift by-wire systems consume excessive power and apply unnecessary load due to the constant use of maximum driving force for all shift range changes, particularly when switching from the P range to the R range, leading to inefficiency and increased power consumption.

Innovation Solution

A shift range switching apparatus that adjusts the driving current output to a motor based on specific set values corresponding to different switching patterns between the P, R, N, and D ranges, reducing power consumption and load by using a control unit to manage the driving current according to the required force for each switching pattern.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the motor is designed to generate maximum driving force for P range to R range switching, then the shift range can be switched reliably, but power consumption increases and unnecessary load is applied to the transmission

Engineering Contradiction:

Improveshift range switching reliabilityVSAvoidmotor power consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The motor output is dynamically adjusted based on the switching pattern. The control unit changes the motor's driving force capability according to the specific shift range transition required, using maximum output only when P-to-R switching is detected, and reduced output for other switching patterns.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The motor's operating parameters (driving force, current supply) are changed based on the switching pattern. The control unit modifies the motor output parameters to match the actual switching requirements, reducing power consumption while maintaining reliable switching.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If maximum driving current is supplied to the motor for all switching patterns, then reliable switching is ensured, but the load on the range position switching unit and automatic transmission increases

Engineering Contradiction:

Improveshift range switching reliabilityVSAvoidload on switching unit

Core Design Contradiction:

ReliabilityVSForce

Solution Approach 1:

The driving current supplied to the motor is dynamically adjusted based on the switching pattern. The control unit provides maximum current only when P-to-R switching is required, and reduces current for other switching patterns, thereby reducing the load on the switching unit and transmission.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The control unit changes the electrical parameters (driving current) supplied to the motor according to the switching pattern, matching the force requirements of each specific shift range transition and minimizing unnecessary load.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If the motor output is set for maximum driving force, then P range to R range switching is reliable, but power consumption increases for all switching operations

Engineering Contradiction:

ImproveP to R switching reliabilityVSAvoidmotor power consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The motor output is dynamically adjusted based on the switching pattern. The control unit changes the motor's driving force capability according to the specific shift range transition required, using maximum output only when P-to-R switching is detected, and reduced output for other switching patterns.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The motor's operating parameters (driving force, current supply) are changed based on the switching pattern. The control unit modifies the motor output parameters to match the actual switching requirements, reducing power consumption while maintaining reliable switching.

Inventive Principle:

Principle #35Parameter changes

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

This approach optimizes power usage and reduces the load on the automatic transmission by providing the necessary driving force only for the specific shift range changes, thereby enhancing efficiency and minimizing unnecessary power consumption and load on the system.

Implementation Method 1

a motor for switching a shift range of an automatic transmission

Methodology Applied

Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Data Source

PatentUS7717006B2Shift range switching apparatus and method for switching shift range

Publication Date: 2010.05.18 DENSO CORP

AI summary

A shift range switching apparatus connects with a motor for switching a shift range of an automatic transmission. The shift range switching apparatus includes a switching unit that is operated by the motor for switching the shift range. The shift range switching apparatus further includes a control unit that outputs a driving current to the motor for switching the shift range to one of a P range, an R range, an N range, and a D range. The control unit controls the driving current at one of a plurality of set values in accordance with a switching pattern of the shift range. The switching pattern may be defined by a combination of two of the P range, the R range, the N range, and the D range.