Electromotive furniture drive, furniture, and method for detecting a position of an electromotive furniture drive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electromotive furniture drives face challenges in cost-effectiveness and energy efficiency for position detection, as existing methods require additional sensors and shunts that increase costs and reduce energy efficiency.
Innovation Solution
The use of semiconductor power switches, particularly MOSFETs, to detect commutation edges by leveraging their internal resistance, eliminating the need for additional shunts and reducing power losses, allowing for efficient position detection without additional voltage drops.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a shunt is used to measure motor current, then position detection is enabled, but energy efficiency drops due to power loss converted into heat
Solution Approach 1:
The patent extracts the measurement function from a separate shunt component and integrates it into the existing semiconductor power switch. The source-drain path of the MOSFET is utilized to detect commutation edges, eliminating the need for an additional shunt and avoiding the associated power losses.
Solution Approach 2:
The semiconductor power switch serves dual functions: it controls the motor current and simultaneously enables position detection through its inherent source-drain path. This multi-functionality eliminates the need for separate measurement components and reduces overall system energy consumption.
2Loss of energy
If a Hall sensor is used to detect motor current, then loss-free detection is achieved, but construction costs increase
Solution Approach 1:
The semiconductor power switch provides its own measurement capability through its inherent source-drain path. This self-service approach eliminates the need for external Hall sensors, maintaining energy efficiency while reducing construction costs and complexity.
Solution Approach 2:
The patent discards the need for expensive Hall sensors by recovering and utilizing the measurement capability already present in the semiconductor power switch's source-drain path, achieving both cost reduction and maintained energy efficiency.
3Measurement precision
If additional shunts are added to the circuit, then position detection is enabled, but device complexity increases
Solution Approach 1:
The patent merges the position detection function with the existing semiconductor power switch by utilizing its source-drain path. This integration eliminates the need for separate shunt components and reduces overall device complexity while maintaining measurement precision.
4Measurement precision
If a shunt is used for current measurement, then position detection is achieved, but heat dissipation increases requiring larger motor control unit
Solution Approach 1:
The patent extracts the measurement function from a separate shunt that would generate heat, and instead uses the inherent source-drain path of the MOSFET which does not convert additional power into heat, thereby eliminating the heat dissipation problem while maintaining position detection capability.
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 approach enables cost-effective and energy-efficient position detection in electromotive furniture drives, reducing construction complexity and operational heat dissipation, while protecting electronic components from voltage peaks.
Implementation Method 1
an evaluation unit is supplied with a voltage dropping across the semiconductor power switch in order to detect commutation edges of the motor
Data Source
AI summary
An electromotive furniture drive includes an adjustment drive for the electromotive movement of a movable furniture component relative to a further furniture component, a control device, and an operating unit. A motor of the adjustment drive is actuated as a function of signals from the operating unit. The control device includes a semiconductor power switch for switching a motor current of the motor, with a voltage dropping across the semiconductor power switch being supplied to an evaluation unit in order to detect commutation edges of the motor.