Electric Linear Motion Actuator with Integrated Locking Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing electric linear motion actuators with a parking brake function require complex assembly, high costs due to separate waterproofing of the linear solenoid, and inefficient energy consumption as the electric motor needs to be kept energized for braking.
Innovation Solution
An electric linear motion actuator with an integrated electric locking mechanism within the motor case, allowing for unitized assembly and reduced energy consumption by locking the power transmission path when de-energized, and utilizing a single multicore cable for power lines to simplify assembly and reduce costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the linear solenoid is attached separately to the electric linear motion actuator, then the parking brake function can be achieved, but the assembly process becomes complex and time-consuming
Solution Approach 1:
The patent combines the linear solenoid for the parking brake function with the electric motor into a single integrated unit. The solenoid is positioned inside the motor case, sharing the same housing and power supply system, which eliminates the need for separate attachment and reduces assembly complexity while maintaining the parking brake functionality
2Adaptability or versatility
If the linear solenoid is attached separately to the electric linear motion actuator, then the parking brake function can be achieved, but separate waterproof treatment is required increasing costs
Solution Approach 1:
The solenoid is integrated within the motor case, allowing both components to share the same waterproof housing and sealing system. This eliminates the need for separate waterproof treatment of the solenoid, reducing manufacturing costs while maintaining the parking brake function
3Reliability
If the electric motor is kept energized to maintain braking force, then the braking force can be maintained, but the power consumption increases
Solution Approach 1:
The patent replaces the continuous electrical actuation system with a mechanical locking system. The solenoid actuates a locking mechanism that mechanically locks the planetary rollers in position, maintaining the braking force without requiring continuous motor energization. This substitution significantly reduces power consumption while maintaining reliability
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
Facilitates easy assembly, reduces costs by eliminating separate waterproofing of the locking mechanism, and minimizes energy wastage by maintaining the braking force without continuous motor energization.
Implementation Method 1
the respective planetary rollers rotate about their axes while revolving around the rotary shaft due to the frictional contact of the planetary rollers with the rotary shaft
Implementation Method 2
By activating a linear solenoid, a locking pin movable toward and away from one of the engagement portions advances
Data Source
Figure 1
Figure 2
Figure 3
AI summary
It is an object of the present invention to assemble an electric linear motion actuator easily. The electric linear motion actuator includes an electric motor (30), a drive shaft (27) configured to be rotated by the electric motor (30), a rotation-to-linear motion converting mechanism (50) configured to convert the rotational motion of the drive shaft (27) to the axial linear motion of an axially movably supported outer ring member (22), and an electric locking mechanism (70) incorporated in a reduction gear mechanism (40) in which the rotation of a rotor shaft (33a) of the electric motor (30) is reduced in speed and transmitted to the drive shaft (27). When the electric locking mechanism (70) is energized, the power transmission path (reduction gear mechanism (40))shifts to the locked state in which power cannot be transmitted through the power transmission path, and when the electric locking mechanism (70) is de-energized thereafter, the power transmission path is kept in the locked state. The electric locking mechanism (70) is built in a motor case (31) of the electric motor (30) so that the electric motor (30) and the electric locking mechanism (70) are unitized.