Single-Trace Cam for Compact Windscreen Wiper Parking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing windscreen wipers face challenges in achieving a compact and cost-effective wiper parking function due to the large radial size of conventional dual-trace cams, which limits integration of additional features without increasing the overall size of the driving system.
Innovation Solution
A windscreen wiper system utilizing a single-trace cam with a conductive parking cam and electrodes, allowing for minimized radial dimensions and integration of both wiper parking and cleaning fluid spray control functions without increasing the system's size, by using a wheel plate with embedded cams and snap structures for secure mounting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a dual-trace cam is used to achieve wiper parking function, then the parking function is reliable, but the radial size of the wheel plate increases
Solution Approach 1:
The cam is segmented into two functional traces: a first trace for controlling the wiper parking function and a second trace for controlling the cleaning fluid spray function. This segmentation allows a single cam to perform multiple functions that previously required separate components, reducing the overall radial size of the wheel plate while maintaining reliable parking control.
2Adaptability or versatility
If additional features are integrated on the wheel plate, then the system functionality increases, but the wheel plate size must increase to accommodate extra cams
Solution Approach 1:
The cam is designed with multiple traces that serve different functions: the first trace controls the wiper parking function while the second trace controls the cleaning fluid spray function. This multi-functionality approach allows a single cam structure to replace what would traditionally require multiple separate cams, enabling feature integration without increasing wheel plate size.
3Reliability
If a magnetic sensor and permanent magnet are used for angular position measurement, then the parking function is achieved, but the cost increases
Solution Approach 1:
The patent replaces the magnetic sensor and permanent magnet system with a purely mechanical detection approach using a cam and contactless electrode arrangement. The cam's geometric profile provides mechanical reference for angular position, and the contactless electrodes detect the cam's position through capacitive coupling, eliminating the need for expensive magnetic components while maintaining measurement accuracy.
4Reliability
If two electrodes with different traces are used, then the parking function is reliable, but the cam radial dimensions increase
Solution Approach 1:
The patent merges the functions of two separate cams into a single cam structure with two distinct traces. The first trace controls the wiper parking function and the second trace controls the cleaning fluid spray function. By combining these functions into one cam, the radial dimensions are reduced compared to using two separate cams, while maintaining reliable functional determination through the contactless electrode detection 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
The solution enables a compact and cost-effective windscreen wiper system that can integrate both parking and cleaning fluid spray control functions, reducing the overall size and maintaining functionality within a predefined angular range of the wiper blade's operation.
Implementation Method 1
The parking electrode is pressed against the surface of the wheel plate under the resilient bias of the parking contact spring
Data Source
AI summary
The present invention relates to a motor vehicle's windscreen wiper, that includes a wiper blade and driving system; where the driving system includes a wiper motor, a wheel plate that pivots about a central rotational axis; where the wheel plate's angular position is associated with the wiper blade's angular position; where a parking cam on the wheel is associated with two parking contact springs with parking electrodes that press against the wheel plate surface under a resilient bias of the parking contact spring; where a parking trace is defined by a track slid by the parking electrode on the wheel plate during the wheel plate's rotation such that distances between the contact spring parking electrodes and the wheel plate's central rotation axis is substantially equal to each other such that traces of the parking electrodes generally coincide with each other; where the invention further includes a single-trace parking cam consisting of only one arc-segment such that the parking trace substantially follows a center arc by; where application of the single-trace cam is able to achieve the wiper parking function of the windscreen wiper in a compact and cost-effective manner.