Shift-Range Actuator Control Using Peak-Pass Detection

Solution Overview

Problem

Conventional shift-by-wire systems face challenges in reliably switching shift ranges without hydraulic mechanisms, leading to reduced responsiveness and potential functional issues when the detent roller does not fall to the bottom of the valley portion.

Innovation Solution

An actuator control device with a drive control part, position determination part, and range determination part is used to control the switching of shift ranges by determining when the engaging member has passed over a peak portion, allowing for quick range determination and improved responsiveness without requiring the detent roller to reach the bottom of the valley.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the detent roller is required to reach the bottom of the valley portion for reliable shift range switching, then the reliability of shift range switching is improved, but the responsiveness is reduced and power consumption increases

Engineering Contradiction:

Improvereliability of shift range switchingVSAvoidresponsiveness of shift range switching

Core Design Contradiction:

ReliabilityVSSpeed

Solution Approach 1:

The patent applies partial action by determining that the engaging member has reached the target valley portion when it has passed over the peak portion, without requiring it to reach the bottom of the valley. This partial determination is sufficient for reliable shift range switching while improving responsiveness and reducing power consumption.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent uses preliminary action by determining the shift range at the timing when the engaging member passes over the peak portion, which occurs before the engaging member reaches the bottom of the valley portion. This preliminary determination allows for faster shift range switching while maintaining reliability.

Inventive Principle:

Principle #10Preliminary action

2Reliability

If the detent roller is required to reach the bottom of the valley portion for reliable shift range switching, then the reliability of shift range switching is improved, but the power consumption increases

Engineering Contradiction:

Improvereliability of shift range switchingVSAvoidpower consumption of actuator

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies partial action by determining that the engaging member has reached the target valley portion when it has passed over the peak portion, without requiring it to reach the bottom of the valley. This partial determination is sufficient for reliable shift range switching while improving responsiveness and reducing power consumption.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent uses preliminary action by determining the shift range at the timing when the engaging member passes over the peak portion, which occurs before the engaging member reaches the bottom of the valley portion. This preliminary determination allows for faster shift range switching while maintaining reliability.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11906045B2Actuator control device

Publication Date: 2024.02.20 DENSO CORP

AI summary

A control device switches a shift range by driving a motor and moving a detent roller in a parking lock system including an electric actuator having the motor and a detent mechanism. A control unit of the control device includes a drive control part, a position determination part and a range determination part. The drive control part controls driving of the motor. When the detent roller is moved to a target valley portion corresponding to the target range, a position determination part determines that the detent roller has passed over a peak portion based on sensor information. The range determination part is configured to estimate that the detent roller has reached the range of the target range corresponding to the target range at a peak passing over determination timing when it is determined that the detent roller has passed over the peak portion.