Vehicle Door Power Drive Module With Normally Closed Brake
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional passenger doors in vehicles lack a power drive module for automated opening and closing, relying on manual operation and complex systems with clutches, which are cumbersome and inefficient.
Innovation Solution
A power door system with a hinge, motor, gearbox, brake assembly, and position sensor, controlled by a controller to automatically open or close the door based on user input, eliminating the need for manual operation and discrete detents, using a linkage assembly to transmit torque to the door pillar.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a power drive module is added to enable automated door opening and closing, then ease of operation is improved, but device complexity increases
Solution Approach 1:
The patent combines the motor, gearbox, brake assembly, and control circuitry into a single integrated power drive module unit. This merging of components simplifies the overall system architecture by consolidating multiple functional elements into one compact assembly, reducing the number of separate mechanical systems that would otherwise be needed to achieve automated door operation.
Solution Approach 2:
The patent replaces traditional mechanical door holding mechanisms (such as door checks with detents) with an electronically controlled brake assembly. The brake assembly uses electromagnetic actuation rather than pure mechanical linkages to control door position, reducing mechanical complexity while maintaining the automated operation capability.
2Reliability
If a brake assembly is used to hold the door in position, then reliability is improved, but device complexity increases
Solution Approach 1:
The brake assembly is designed with a spring-applied, electrically-released mechanism that defaults to the held position (normally closed). This self-service design means the brake automatically engages to hold the door without requiring continuous electrical power or active control, improving reliability while minimizing the complexity of the control system needed to operate it.
Solution Approach 2:
Instead of using a brake that is normally released and requires continuous power to hold the door open, the patent inverts the logic by using a brake that is normally engaged (holding the door) and only releases when power is applied. This inversion improves reliability by using the default mechanical state for safety-critical door holding while reducing electrical system complexity.
3Extent of automation
If a position sensor and controller are added to detect door movement and command motor operation, then automation capability is improved, but device complexity increases
Solution Approach 1:
The position sensor serves multiple functions: it detects door open/closed status, monitors door movement during operation, and provides feedback for the control algorithm to determine when the door has reached its target position. This multi-functionality reduces the need for separate sensors for each detection task, thereby improving automation capability without proportionally increasing device complexity.
Solution Approach 2:
The control system uses feedback from the position sensor to automatically adjust motor operation. The controller continuously monitors the door position and compares it to the desired position, then commands the motor to stop when the door reaches the target. This closed-loop feedback control achieves high-level automation using a relatively simple control algorithm, avoiding the need for complex mechanical positioning mechanisms.
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 seamless automated opening and closing of passenger doors without manual effort, providing a reliable and efficient operation by using a back-drivable gearbox configuration and adjustable brake torque, enhancing user experience and reducing mechanical complexity.
Implementation Method 1
the brake assembly includes a permanent magnet grounding the shaft member to the housing in the normally closed position
Implementation Method 2
A coil is configured to overcome a magnetic flux of the permanent magnet to provide an open position that permits the shaft member to freely rotate relative to the housing
Data Source
Figure 1A~1B
Figure 2~3A
Figure 3B
AI summary
A vehicle door power drive module, and an associated method of opening a vehicle door, are described. The power drive module comprises a housing and a motor arranged in the housing. First and second gearboxes are also arranged in the housing, the first second gearboxes being coupled in series with one and other by a shaft member, the first gearbox connecting the motor to the second gearbox, with an output shaft coupled to the second gearbox. The power drive module further comprises a brake assembly selectively connected to the shaft member, the brake assembly having a normally closed position in which the shaft member is grounded to the housing, and including an open position corresponding to one of a door closing mode and a door opening mode. The shaft member is configured to be rotatable relative to the housing in the brake open position in response to the motor driving the first gearbox. The power drive module also comprises a position sensor to detect rotation of the output shaft.