Inductive sensor

About: Inductive sensor is a research topic. Over the lifetime, 2282 publications have been published within this topic receiving 21984 citations.

Circuit for mooting broken or chipped teeth of encoder wheels via comparing temporal fluctuations between rising or falling edges and using edge with least fluctuation

Abstract: A method and a device for detecting rotational speed with an inductive sensor in which a sinusoidal potential is induced by a magnet wheel and then fed to a filter with a comparator connected downstream of the filter and therefrom into a square-wave signal that is essentially proportional to the rotational speed of the magnet wheel. This output signal of the comparator is evaluated in a microcomputer. In this evaluation, only the same type of edges of the comparator signal are evaluated, specifically those in which the intervals fluctuate less when considered over a certain time span. The microcomputer here can initially evaluate both types of edges, that is, positive and negative edges, and then use those edges in which smaller fluctuations, that is, interference, are determined for calculating the rotational speed. The microcomputer can also first evaluate only one type of edges and change over to edges of the other type only if the former displays interference above a present value. If the edges of the other type show even greater interference than those of the first type, then the system switches back to the first type. The changeover can be done either in the microcomputer or externally. The external changeover to the type of edge can be done by an external inverter or by reversing the polarity of the sensor output signals by means of a controllable switch.

Partition illumination energy-saving switch control system and control method thereof

Abstract: The invention discloses a partition illumination energy-saving switch control system and a control method of the system. The system is composed of at least one camera, at least one human body inductive sensor, a microcontroller, at least one relay, a plurality of lamps and a computer, wherein the camera is connected with the microcontroller through a USB interface, and the human body inductive sensor and the relay are connected with the microcontroller through a GPIO port; a brightness calculation program module, an image preprocessing program module and an image processing program module are embedded in the microcontroller; the microcontroller is connected with the computer through a USB interface or a serial port; the computer comprises a system parameter setting program module. The method is based on an image processing technology, a partition illumination mechanism is introduced so that partition illumination can be achieved, and the lamps in the areas where people exist or do not exist can be automatically turned on or off along with movement of people. According to the control system and the control method of the system, due to partition illumination and human body following illumination, huge waste of electric energy can be effectively avoided, and intelligent illumination is achieved.

Systems and methods for offset reduction in sensor devices and systems

Abstract: Embodiments relate to systems and methods for reducing errors in sensor devices and systems. In embodiments, the sensor devices comprise magnetic field sensor devices, such as ordinary or vertical Hall sensor devices, and the error to be reduced is a residual offset error, though in other embodiments other sensor devices can be used and/or other types of errors can be targeted for reduction or elimination. In one embodiment, at least two such sensor devices not electrically coupled with one another are sequentially operated in a spinning current-type mode such that an individual output signal from each of the at least two sensor devices is obtained. A total output signal can then be calculated, such as by averaging or otherwise combining the individual output signals from each sensor device.

Improving Sensitivity of a Micro Inductive Sensor for Wear Debris Detection with Magnetic Powder Surrounded

Abstract: The inductive detection of wear debris in lubrication oil is an effective method to monitor the machine status. As the wear debris is usually micro scale, a micro inductive sensor is always used to detect them in research papers or high-tech products. However, the improvement of detection sensitivity for micro inductive sensors is still a great challenge, especially for early wear debris of 20 μm or smaller diameter. This paper proposes a novel method to improve the detection sensitivity of a micro inductive sensor. Regarding the magnetic powder surrounding the sensor, the magnetic field in the core of the sensor where the wear debris pass through would be enhanced due to the increased relative permeability. Thus, the inductive signal would be improved and the detection sensitivity would be increased. It is found that the inductive signal would linearly increase with increasing the concentration of the magnetic powder and this enhancement would also be effective for wear debris of different sizes. In addition, the detection limit of the micro inductive sensor used in our experiment could be extended to 11 μm wear debris by the proposed method.

Cylinder discriminating sensor layout

Abstract: A sensor arrangement for an internal combustion engine so as to provide a signal when one cylinder of the engine is at a pre-determined position. The sensor arrangement includes an inductive sensor that is mounted directly in the cam cover of the engine and which cooperates directly with one of the cam lobes.