Vehicle Ultrasonic Sensor Transformer Winding for Magnetic Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ultrasonic sensors in motor vehicles are susceptible to magnetic interference fields, particularly in the kilohertz range, which can cause noise signals and are not effectively shielded by existing cylindrical shielding plates, leading to high material and labor costs.
Innovation Solution
The ultrasonic sensor incorporates a compensation winding within the housing assembly, axially parallel to the transformer element's functional winding, inducing currents of opposite polarity to counteract external magnetic interference, potentially eliminating the need for additional shielding plates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a cylindrical shielding plate is mounted on the transformer, then electrical interference shielding is improved, but magnetic interference shielding remains insufficient and manufacturing complexity increases
Solution Approach 1:
The patent merges the shielding function with the transformer element by integrating a compensation winding directly into the transformer structure. The compensation winding is wound around the same magnetic core as the functional winding, combining the transformer's magnetic circuit function with the shielding function into a single integrated component, thereby eliminating the need for separate shielding plates and reducing structural complexity
Solution Approach 2:
The compensation winding acts as an intermediary element that generates a counteracting magnetic field to neutralize external magnetic interference. By introducing this intermediate component that produces an opposing magnetic field, the system achieves magnetic shielding without requiring complex physical barriers or additional shielding structures
2Reliability
If a cylindrical shielding plate is mounted on the transformer, then some interference protection is provided, but magnetic shielding effectiveness is limited and costs increase
Solution Approach 1:
The shielding function is merged with the existing transformer element by integrating the compensation winding into the transformer's magnetic core structure. This integration eliminates the need for separate shielding plates, reducing material costs and simplifying the manufacturing process while maintaining reliable interference protection
Solution Approach 2:
The transformer element is given multiple functions: it serves both as the signal transformation component and as the magnetic shielding element through its compensation winding. This multi-functionality reduces the total number of components needed, lowering both material and labor costs while ensuring reliable interference protection
3Object-affected harmful factors
If a compensation winding is added to shield against magnetic interference, then magnetic shielding is improved, but device complexity increases
Solution Approach 1:
The compensation winding is merged with the functional winding by winding both around the same magnetic core and connecting them in series. This integration creates a unified magnetic circuit where the shielding function is achieved through the interaction of the two windings, avoiding the need for separate shielding components and reducing overall device complexity
Solution Approach 2:
The compensation winding is designed to automatically generate a counteracting magnetic field in response to external magnetic interference without requiring external control or additional complex circuitry. The series connection ensures that the compensation winding self-adjusts to provide shielding, eliminating the need for complex control systems
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 effectively shields against magnetic interference, reduces material and labor costs, and maintains signal quality by compensating for induced currents, enhancing the sensor's performance.
Implementation Method 1
A winding direction of the compensation winding, a winding direction of the functional winding of the transformer element and a polarity of the series connection are arranged such that currents of opposite polarity can be induced in the compensation winding and in the functional winding
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an ultrasonic sensor (1) for a motor vehicle (80). The ultrasonic sensor (1) comprises: a housing assembly (5), an ultrasonic membrane (2) disposed in an opening in the housing assembly (5), an acoustic transducer element (3) attached to the ultrasonic membrane (2) from the inside and a circuit board (6) which is disposed in the housing assembly (5) and on which a driver circuit (9) for the acoustic transducer element (3) is mounted, the driver circuit (9) having a transformer element (11). The housing assembly (5) of the ultrasonic sensor (1) has a compensating winding (16) which is disposed axially parallel to a functional winding (15) of the transformer element (11) and is connected in series with the functional winding (15) of the transformer element (11). A winding direction of the compensating winding (16), a winding direction of the functional winding (15) of the transformer element and a polarity of the series connection are designed in such a way that currents of opposite polarity can be induced in the compensating winding (16) and in the functional winding (15).