Automatic Shift Device Sleeve Engagement Control

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Solution Overview

Problem

Existing automatic shift devices for automated transmissions in vehicles require a lengthy time to determine if a sleeve is not engaged with a gear, leading to increased shift times due to reliance on a predetermined estimated time for engagement.

Innovation Solution

The automatic shift device employs a dog clutch mechanism with a sleeve and clutch ring configuration, including a push force reduction control and retry control, which detects back and forth movement of the sleeve to determine engagement status earlier, and adjusts push force based on rotation speed and clutch tooth groove passage counts to facilitate earlier and smoother engagement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a predetermined estimated time is used to determine sleeve engagement status, then the determination method is simple, but the shift time becomes long

Engineering Contradiction:
Improvedetermination method complexityVSAvoidshift time
Core Design Contradiction:
Device complexityVSLoss of time

Solution Approach 1:

The patent uses feedback from the stroke sensor to detect the actual position of the sleeve during movement. The control unit continuously monitors the stroke signal and determines engagement status based on whether the sleeve has reached the predetermined stroke position within the engagement time, rather than waiting for a fixed predetermined estimated time to elapse. This feedback mechanism enables real-time determination and reduces unnecessary waiting time.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent replaces the time-based mechanical waiting mechanism with an electronic detection system. Instead of mechanically waiting for a predetermined time period to determine engagement, the system uses a stroke sensor to electronically detect the sleeve's position and provides immediate feedback to the control unit, which then determines engagement status based on the actual stroke achieved within the available time.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If the sleeve is pushed with constant predetermined torque, then the engagement process is simple, but the sleeve may not smoothly reach the engagement position

Engineering Contradiction:
Improvecontrol process complexityVSAvoidengagement smoothness
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies dynamic control to the sleeve movement process. The control unit continuously monitors the stroke sensor signal and adjusts the driving motor's output torque in real-time based on the sleeve's actual position and movement characteristics. This dynamic adjustment ensures the sleeve reaches the engagement position smoothly and reliably, adapting to variations in mechanical resistance and alignment during the engagement process.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the torque parameter during the engagement process based on the sleeve's position. The control unit adjusts the driving torque as a function of the detected stroke, increasing or decreasing torque as needed to ensure smooth engagement. This parameter change approach allows the system to optimize engagement performance by adapting torque levels to the specific mechanical conditions encountered during each engagement cycle.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2816249B1Automatic shift device for automated transmission for vehicle
Publication Date: 2016.11.23 AISIN SEIKI KK
  • EP2816249B1 patent drawingFigure 1
  • EP2816249B1 patent drawingFigure 2
  • EP2816249B1 patent drawingFigure 3

AI summary

An automatic shift device (10) for an automated transmission (13) for a vehicle (M) includes a rotation shaft (22, 28), a clutch ring (23, 24), a clutch hub (25), a sleeve (26), a dog clutch portion (23a, 24a), a shaft moving apparatus (27), and a control portion (33). The control portion (33) includes a push force reduction control portion (33a) performing a push force reduction control reducing a push force (F) of the sleeve (26) that the shaft moving apparatus (27) applies on the clutch rear teeth (23c1) in response to a back and forth movement of the sleeve (26) after the sleeve (26) reaches an end surface (23c2) of the clutch rear tooth (23c1). The control portion (33) includes a retry control portion (33b) performing a retry control that re-applies the push force (F) of the sleeve (26) in response to a predetermined retry condition after the push force reduction control is performed.