Smart Position Switch
It is the magnetic switch. Smart Position Switch consists of one reed switch and one magnet, with wires as well. It is the simple and low price switch for many industry applications. Here you can have your ideas come true for the Inductive Switch, Position Switch, Magnet...
Smart Position Switch
It is the magnetic switch. Smart Position Switch consists of one reed switch and one magnet, with wires as well. It is the simple and low price switch for many industry applications.
Can not only replace the trip switch to complete the trip control and limit protection, but also for high-count, speed, liquid level control, part size detection, processing procedures such as automatic convergence. Because it has the characteristics of non-contact triggering, fast action speed, can operate within different detection distances, the signal is stable and pulseless, the work is stable and reliable, the service life is long, the repeat positioning accuracy is high, and it can adapt to the harsh working environment. It is widely used in machine tools, textiles, printing, plastics and other industrial production.
Proximity switch is classified according to the working principle: there are mainly high-frequency oscillation type, Hall type, ultrasonic type, capacitive type, differential coil type, permanent magnet type, etc. Among them, high frequency oscillation type is most commonly used.
Permanent magnet type: It uses the attraction force of a permanent magnet to drive a reed switch to output a signal.
Differential coil type: It uses the difference between the eddy current and the magnetic field generated when the object to be detected approaches, and operates by the difference between the detection coil and the comparison coil.
Capacitive proximity switch: It is mainly composed of a capacitive oscillator and an electronic circuit. Its capacitance is located on the sensor interface. When the object approaches, it will oscillate due to the change of its coupling capacitance value, thus generating oscillation or stopping the oscillation to make the output signal. Changed. Capacitive proximity switches can be triggered with a variety of materials, such as solid, liquid, or powdered objects.
Hall proximity switch: It works by converting magnetic signals into electrical signals. Its output has a memory retention function. The internal magnetic sensitive device is only sensitive to the magnetic field perpendicular to the sensor face. When the magnetic pole S is close to the proximity switch, the output of the proximity switch produces a positive transition and the output is high. If the magnetic pole N is directly opposite to the switch, the output is low. Level.
Ultrasonic proximity switch: mainly composed of piezoelectric ceramic sensors, electronic devices for transmitting ultrasonic waves and receiving reflected waves, and programmable bridge switches for adjusting the detection range. Suitable for detecting inaccessible or inaccessible targets whose control function is not interfered by sound, electricity, light and other factors. The detection target can be a solid, liquid, or powder state object, as long as it can reflect ultrasonic waves.
High frequency oscillating proximity switch: it is triggered by metal, mainly composed of high frequency oscillator, integrated circuit or transistor amplifier and output device. Its working principle is: the coil of the oscillator generates an alternating magnetic field on the acting surface of the switch. When a metal object approaches the active surface, the eddy current generated inside the metal object will absorb the energy of the oscillator and cause the oscillator to stop vibration. Oscillation of the oscillator and stop the vibration of these two signals, after shaping and amplified into a binary switch signal, and output switch control signal.
HOW TO SELECT YOUR TARGET PROXIMITY SWITCH
For different material samples and different detection distances, different types of proximity switches should be selected so that they have a high performance-to-price ratio in the system. Therefore, the following principles should be followed in the selection:
1, When the detector is metal, a high-frequency oscillatory proximity switch should be used. This type of proximity switch is most sensitive to iron-nickel and A3 steels. For aluminum, brass and stainless steel samples, the detection sensitivity is low.
2, When the detection body is non-metallic material, such as wood, paper, plastic, glass, and water, a capacitive proximity switch should be used.
3, When metal objects and non-metals are to be detected and controlled over long distances, photoelectric proximity switches or ultrasonic proximity switches should be used.
4, When the detection body is metal, if the detection sensitivity is not high, an inexpensive magnetic proximity switch or Hall proximity switch can be selected.
5, proximity switch specification detection
6, Movement distance measurement; When the action piece is close to the sensing surface of the proximity switch, the proximity switch action distance is the maximum operating distance of the proximity switch, and the measured data should be within the product's parameter range.
7, Determination of the release distance; when the action piece moves from the front side away from the sensing surface of the proximity switch and the switch changes from motion to release, the maximum distance from the action surface is measured.
8, Determination of hysteresis H; absolute value of the difference between the maximum movement distance and the release distance.
9, Determination of the operating frequency; using a speed-regulating motor to drive the bakelite disc, fixing a number of steel pieces on the disc, adjusting the distance between the switch sensing surface and the action piece, about 80% of the switching distance, rotating the disc, in turn The action piece is close to the proximity switch. A speed measuring device is installed on the spindle of the disc. The output signal of the switch is shaped and connected to a digital frequency meter. At this time start the motor, and gradually increase the speed, under the conditions of the product of the speed and the action piece and the frequency count equal, the frequency of the switch can be read directly by the frequency meter.
10, Repeat accuracy measurement; The action piece is fixed on the measuring tool, and the motion speed is controlled at 0.1 mm/s from the switch action distance of 120% of the distance, from the front of the switch sensing surface to the action area of the switch. When the switch is activated, read the reading on the gage and then exit the action zone to turn the switch off. Repeat this 10 times, and finally calculate the difference between the maximum and minimum values of 10 measurements and the 10 average values, and the difference is the repeat accuracy error.