Composition and Structure of Needle Detector

April 19,2022

A needle detector is a kind of ferromagnetic metal induction instrument. It is a detection instrument applied to the textile industry under the classification of metal detectors. It is mainly used for the detection of ferromagnetic metal foreign matters in textiles.


needle detector


Detection sensor (probe)


It is composed of an upper detection sensor and a lower detection sensor (located under the conveyor belt) to form the passing height of detection articles of different specifications, which is referred to as the detection height for short.


Circuit control system


The signal amplification circuit, signal loop alarm system, and power protection circuit are composed of three parts: iron foreign matters can be captured more quickly through signal amplification. When iron foreign matters impact and destroy the normal magnetic cutting line, the magnetic cutting line will be distorted and deformed. At this time, the electric circuit outputs the trigger signal to form an alarm loop to achieve the ideal effect of detection and alarm.


Electric machinery


Principle of gear reduction single-phase capacitor rotating motor: gear speed ratio rotation, reduce load and prolong service life.


Conveyor belt


The function of the conveyor belt is to carry the items to be detected through the detection sensor for detection. Therefore, the anti-static special nylon is adopted, the warp and weft are woven into mesh cloth, and the surface is bonded with special rubber to absolutely ensure that the conveyor belt does not contain any iron and metal components, to ensure that there is no alarm when the sensor is detected.




The frame made of steel plate achieves the bridge function of the whole needle testing machine. It is the primary frame of the multi-functional state structure of the needle testing machine, making its performance more stable and its appearance electrostatic spraying, which is not only beautiful but also prolongs its service life.


Wing shell


Since the aluminum plate shell is made by hand, it is suitable for manufacturers with small production volumes or customized non-standard machines. Powerful manufacturers use self mold opening engineering hard plastic shells.


Transmission shaft


The four transmission shafts with the rolling structure are made of stainless steel pipe and plane bearing, to ensure the transmission concentricity, smooth transmission lubrication, low noise, low heat, and prolonged service life.


Photoelectric infrared reflector


In the working state, an invisible infrared ray will be emitted. When the tested object passes through, the infrared ray will intercept and send a signal to the recorder, and finally count the qualified articles.


Fixed foot


Each machine has 4 fixed feet, which can adjust stably and firmly when installing the machine until the machine does not shake.


Control panel


It is used to control machine operation, sensitivity debugging, display counting, and other functions.


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