Swing Door Actuator With Non-Back Drivable Gear and Slip Clutch
Solution Overview
Problem
Vehicle passenger doors that pivot about a vertical axis face issues with unbalanced weight causing improper opening or closing when the vehicle is on an incline, and existing power actuation systems do not provide seamless fully-powered open and close functionality with an infinite door check feature.
Innovation Solution
A swing door actuation system with a non-back drivable gear train and a clutch that can be disengaged to allow manual operation, featuring a motor connected to a gear train and an extensible member for linear motion conversion, providing infinite door check functionality and manual operation capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If a power actuator is provided for swing doors, then fully-powered open and close functionality is achieved, but device complexity increases
Solution Approach 1:
The patent combines the power actuator, clutch mechanism, and door check functionality into a single integrated assembly. The motor, gear train, and clutch are merged into one unit that provides both powered operation and manual override capabilities, eliminating the need for separate components and reducing overall system complexity.
Solution Approach 2:
The actuator system is designed to perform multiple functions: powered door opening, powered door closing, manual door operation, and infinite door check positioning. This multi-functionality is achieved through the clutch mechanism that can engage or disengage based on operational mode, allowing a single device to replace what would traditionally require multiple separate systems.
2Ease of operation
If a clutch mechanism is added to allow manual operation, then ease of operation is improved, but device complexity increases
Solution Approach 1:
The clutch mechanism is designed to automatically engage or disengage based on the operational conditions. When the motor attempts to operate, the clutch automatically engages to connect power; when manual operation is detected or power is unavailable, the clutch automatically disengages to allow free manual movement. This self-regulating behavior eliminates the need for complex control systems or additional actuators to manage the clutch state.
3Reliability
If a non-back drivable gear train is used, then reliability is improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent replaces traditional back-drivable gear mechanisms with a non-back drivable gear train design. This substitution eliminates the need for complex detent mechanisms or separate locking systems, as the gear train itself inherently prevents back-driving and holds door position reliably. The worm gear or planetary gear configuration provides inherent mechanical locking without requiring additional precision-crafted detent features.
4Ease of operation
If infinite door check functionality is provided, then ease of operation is improved, but device complexity increases
Solution Approach 1:
The actuator system provides infinite door check positioning as an inherent capability rather than a separate mechanism. The motor-controlled extensible member can hold the door at any position within its travel range by simply maintaining its extended length, eliminating the need for traditional finite detent mechanisms or separate infinite door check assemblies. This multi-functional design integrates positioning, holding, and movement capabilities into a single system.
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 fully-powered opening and closing of swing doors with an infinite door check feature, allowing users to manually operate the door with minimal effort, even without electrical power, preventing uncontrolled swinging and reducing manual effort and noise.
Implementation Method 1
a motor operatively connected to a gear train
Implementation Method 2
a motor operatively connected to a gear train that is non-back drivable
Implementation Method 3
The clutch has a slip torque that is sufficiently high to prevent movement of the door when the door is exposed to less than a selected external torque and when the motor is stopped
Data Source
AI summary
A swing door actuation system for moving a door about a pivot axis between open closed positions relative to a vehicle body. The system includes a power swing door actuator having a housing connectable to one of the swing door and the vehicle body, an extensible member that moves relative to the housing, and connects to the other of the swing door and the vehicle body, a motor connected to a gear train, and a normally engaged clutch. The motor is operatively connected to a clutch input end through the gear train. The output end is operatively connected to the extensible member. The clutch is disengageable to disconnect the motor from the extensible member. The clutch has a slip torque that is sufficiently high to prevent movement of the door when the door is exposed to less than a selected external torque and the motor is stopped.