Plastic Spindle Nut for Vehicle Door Actuator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spindle drives for motor vehicle doors are costly and complex due to the need for a separate, cost-intensive assembly step for the metal spindle nut, which also contributes to noise and vibration issues.
Innovation Solution
A spindle drive design featuring a plastic spindle nut with openings on its outer circumference that engage with holding extensions, allowing direct injection molding onto a thrust tube, simplifying production and providing a strong, durable connection without material pairing issues, and reducing noise and vibration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a metal spindle nut is used in the spindle drive, then high forces can be transmitted reliably, but the production becomes cost-intensive and complex due to separate assembly steps
Solution Approach 1:
The patent combines the spindle nut and thrust tube into a single integrated plastic component manufactured through injection molding. This merging eliminates the need for separate assembly steps while maintaining the structural integrity required for high force transmission in the spindle drive mechanism.
Solution Approach 2:
The patent employs a plastic material for the spindle nut that combines rigidity for force transmission with manufacturing efficiency. This material selection allows the component to be produced as a single piece through injection molding while still withstanding the high forces required for door actuation.
2Strength
If a metal spindle nut is used in the spindle drive, then the connection strength is sufficient, but noise and vibration are increased
Solution Approach 1:
The patent changes the material parameter from metal to plastic for the spindle nut. This parameter change reduces noise and vibration generation while maintaining sufficient connection strength through the plastic material's inherent damping properties and optimized structural design.
Solution Approach 2:
The patent converts the potential weakness of plastic material into a benefit by utilizing its noise-damping and vibration-reducing properties. The plastic spindle nut absorbs and dampens vibrations that would otherwise be generated and transmitted by metal components, turning a perceived material limitation into a noise reduction advantage.
3Reliability
If a separate assembly step for the spindle nut is implemented, then the connection is durable, but the production time and cost increase
Solution Approach 1:
The patent merges the spindle nut and thrust tube into a single injection-molded component. This integration eliminates the separate assembly step required for metal spindle nuts, thereby improving production efficiency and reducing manufacturing time while maintaining connection durability through the integrated design.
Solution Approach 2:
The spindle nut is pre-formed as an integrated part of the thrust tube through injection molding during the main production process. This preliminary action eliminates the need for subsequent separate assembly operations, streamlining production while ensuring durable connections are built-in from the start.
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
This design simplifies production, reduces costs, and minimizes noise and vibration by using a plastic spindle nut with a strong connection to the thrust tube, enhancing the overall efficiency and reliability of the spindle drive.
Implementation Method 1
a threaded spindle (25), an electric motor (21) which is rotatably connected to the threaded spindle (25) and drives the motor vehicle door
Implementation Method 2
The spindle nut made of plastic also has a positive effect on noise development and reduces the generation and transmission of vibrations to the body components
Data Source
Figure 1
Figure 2
Figure 3~5
AI summary
The present invention relates to a drive device for moving a motor vehicle door (3), in particular a side door, a tailgate or a trunk lid, in order to move it from a first position to a second position, comprising a telescopically extendable tubular outer housing (11) formed from a first (7) and a second (9) housing tube, one end of which can be attached to the body (15) of a motor vehicle (1) and the other end of which can be attached to the motor vehicle door (3), a spindle drive (20) mounted in the outer housing (11) with a threaded spindle (25), an electric motor (21) which is rotatably connected to the threaded spindle (25) for driving the motor vehicle door (1), and a spindle nut (33) arranged non-rotatably in a guide tube (31), which, when the threaded spindle (25) is rotated, performs a translational movement along the spindle axis and transmits this translational movement to a thrust tube (35).so that the housing tubes (7, 9) move telescopically relative to each other to move the vehicle door from the first to the second position. The spindle nut is made of plastic and the thrust tube (35) has openings (51) on its outer circumference into which retaining projections (53) of the spindle nut (33) engage.