Photoelectric sensor is controlled by converting changes in light intensity into changes in electrical signals. It is generally composed of three parts, which is divided into transmitter, receiver and detection circuit. The transmitter is aimed at the target and emits a light beam, which generally originates from semiconductor light sources, light emitting diodes (LEDs) and laser diodes. The beam is fired uninterrupted, or the pulse width is changed. The receiver consists of photodiodes or phototransistors. In front of the receiver, optical elements such as lenses and apertures are installed. Behind it is the detection circuit, which filters out the valid signal and applies it. The through beam type is that the transmitting end emits red light or infrared light, and the receiving end receives it.
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Mechanical vibration and noise are key factors when designing a brushless DC motor. Uncontrolled noise and vibration often cause rapid system degradation, affect efficiency, and adversely affect wear on this control system. This is especially true of sensitive medical equipment, robotics, commercial systems, and handheld devices. Noise and vibration can have a significant impact on system performance, reliability, and operating costs. For handheld devices, vibration can be transferred to the user, causing safety concerns and pressure injuries. Whether in a hospital, laboratory or office, excessive noise from motors running around people can be a health hazard.
The brushless DC vibration motor consists of a motor body and a driver and is a typical mechanization product. The star winding of the motor is mostly made into a three-phase symmetrical star connection, which is very similar to the three-phase asynchronous motor. A magnetized permanent magnet is attached to the rotor of the motor. In order to detect the polarity of the motor rotor, a position sensor is installed in the motor. The driver consists of power electronic devices and integrated circuits.
VFD is mainly composed of rectification (AC to DC), filtering, inverter (DC to AC), braking unit, drive unit, detection unit and micro-processing unit. The VFD adjusts the voltage and frequency of the output power supply by turning on and off the internal IGBT, and provides the required power supply voltage according to the actual needs of the motor, thereby achieving the purpose of energy saving and speed regulation. In addition, the inverter has many protection functions. Such as overcurrent, overvoltage, overload protection and so on. VFD is frequently used for speed regulation of AC motors or reducing the impact on the power grid on start-up.
A stepper motor, also known as step motor or stepping motor, is a brushless DC electric motor that divides a full rotation into a number of equal steps. The motor's position can be commanded to move and hold at one of these steps without any position sensor for feedback (an open-loop controller), as long as the motor is correctly sized to the application in respect to torque and speed.
Variable Frequency Drive changes the voltage of the motor power supply while changing the frequency of the motor power supply, so that the magnetic flux of the motor is kept constant, and the efficiency and power factor of the motor do not decrease in a wide speed regulation range. Because it is the ratio of control voltage (V) to frequency (F), it is called V/F control. And its V/F control features are simple control circuit structure, low cost, good mechanical properties and hardness, which can meet the smooth speed regulation requirements of general transmission.
Three-phase asynchronous motor is a kind of induction motor, which is powered by a 380V three-phase AC current at the same time. Because the rotor and stator rotating magnetic fields of the three-phase asynchronous motor rotate in the same direction, the rotational speed is different, and there is a slip rate, so it is called a three-phase asynchronous motor. The rotor speed of an ATO three-phase asynchronous motor is lower than the speed of the rotating magnetic field. The rotor windings move relative to the magnetic field to generate electromotive force and current and interact with the magnetic field to generate electromagnetic torque to realize energy conversion.
A soft starter is an additional device that can be added to a typical AC electric motor that will allow the motor to use a different startup method. The purpose of this device is to reduce the strain put on the motor during the typical power-up phase of a motor. To accomplish this, a soft starter will slowly and gradually begin applying increasing voltages to the motor. This allows for a smooth acceleration of power instead of a sudden and violent burst of power that could potentially cause damage to the motor and the machine as a whole.
Servo lock is essentially a braking mode. When the servo motor driver selects the speed control mode, closed-loop position control cannot be performed. Therefore, the stop position of the servo motor is random, and there is no holding torque after stopping. At this time, If there is an external force (such as gravity) on the load, it may cause the servo motor to move and deviate from the stop point after it stops.
The PLC program interlocks the forward and reverses the rotation of the motor to prevent the wrong touch of the motor's reverse rotation button. PLC and the VFD are powered on for 2s time control. After the motor stops, it needs to wait for 10s before the motor can be restarted. This is very practical in practical applications (there is a good buffer process for motor inertial motion).
A monitoring relay is a commonly used electromagnetic relay that is used for the voltage protection and control of the power drag system. The coil is connected to the main circuit in parallel to sense the line voltage of the main circuit; the contact is connected to the control circuit and is the executive element. According to the size of the pull-in voltage, voltage monitoring relays can be divided into over-voltage relays and under-voltage relays. ATO monitoring relay has a great many function, including overvoltage protection, undervoltage protection, voltage unbalance protection, phase failure protection and wrong phase protection.
Thermal label printer is that a semiconductor heating element is installed on the print head, and the print head can print out the required pattern after heating and contacting the thermal printing paper. Its principle is similar to that of a thermal fax machine. The image is created by heating the membrane to create a chemical reaction. This thermal label printer chemical reaction takes place at a certain temperature. High temperatures speed up the chemical reaction. When the temperature is below 60℃, it takes quite a long time, even years, for paper to become dark. At 200℃, the reaction takes place in a matter of microseconds.
A solenoid valve is an on/ off electromechanically operated valve which consists of an electromagnetic actuator (solenoid) and a valve body. The solenoid-plunger assembly is the valve actuator responsible for opening and closing the valve. This actuator can be arranged in such a way that the plunger action can either open or close only. There is no intermediate, or in-between position, so there is no way for a solenoid to throttle flow. The valve body consists of the pressure containing parts in-contact with the process fluid.
The DC servo motor has many advantages, including low cost, simple structure, large starting torque, wide speed regulation range and easy control. It is easy to maintain (replacement of carbon brushes) and it has requirements for the environment. Therefore, it can be used in general industrial and civil occasions. Next we'll look at how to control DC servo motor speed with analog.
Stepper motor is an open-loop control motor that divides a full rotation into a number of equal steps. The motor's position can be controlled to move and hold at one of these equal steps. Stepper motors come in many different sizes and styles, and they are widely used in a variety of automated control systems.
A push-button switch is an electrical appliance that is used to connect and disconnect small current circuits that is pressed to act and released to reset. It is generally used in control circuits with AC and DC voltages below 440V and currents less than 5A. Generally, it does not directly manipulate the main circuit, but can also be used in interconnecting circuits.
Computer Numerical Control (CNC) routers are a class of machine shop equipment used to remove material from specific locations on wood or metal. Since each material has different advantages and disadvantages, there are different types of CNC milling machines. Computer numerical control refers to computer programming used to control and program routers. CNC routers are used to create patterns or cuts as needed. Industrial CNC routers used in factory settings are much more expensive than hobbyist models. CNC routers are attached to a table and programmed to remove material in a specific pattern or shape from a piece of wood or metal. The engraving machine is usually connected to a three-speed or four-speed motor system.
The limit switch is a commonly used small current master electrical appliance. It utilizes the collision of the moving parts of the production machinery to make or break the control circuit to achieve certain control purposes. Usually, this ATO limit switch is used to limit the position or stroke of mechanical movement, so that the moving machinery can automatically stop, reverse movement, variable speed movement or automatic round-trip movement according to a certain position or stroke.
This is because the structure of the inverter is AC-DC-AC. Whether single-phase 220V or three-phase 380V, the input AC power must first pass through a three phase rectifier bridge or a single-phase rectifier bridge to convert the AC power into DC power, and then use the point The capacitor filter is removed, and it becomes a DC power supply with relatively flat ripples. Next, the three-phase bridge-type urinal controlled by the chip converts the DC power supply into a three-phase AC power supply whose frequency and voltage can be controlled arbitrarily.
A pressure sensor is a device that can sense the pressure signal and convert the pressure signal into a usable output electrical signal according to a certain law. It usually consists of a pressure-sensitive element and a signal processing unit. According to different test pressure types, pressure sensors can be divided into gauge pressure sensors, differential pressure sensors, and absolute pressure sensors. ATO pressure sensor is the most commonly used sensor in the industry. It is widely used in various industrial automation environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automation, aerospace, military, petrochemical, oil wells, electricity, ships, machine tools, pipeline and many other industries.
