Nema 17 Stepper Motor

I. Definition and naming rules

stepper motor is an open-loop control motor that converts electrical energy into mechanical energy through electrical pulse signals. Stepper motor mainly consists of stator and rotor, with winding on stator, and rotor is permanent magnet or variable reluctance core. Each revolution is divided into discrete steps. Taking the common 1.8 step angle as an example, 200 pulses are required for each turn, that is, 360 °/1.8 ° = 200 steps. And each step sends a separate pulse to the motor. The stepper motor can only take one step at a time, and the size of each step is the same. The pulse of each step will make the motor rotate a precise angle, usually 1.8 °. Its working principle is to make the rotor rotate gradually through a fixed stepping angle, so it has high precision and good control characteristics. The name of NEMA17 stepper motor is derived from the standard formulated by the American Electrical Manufacturers Association. The standard of NEMA17 stepper motor is short for National Electrical Manufacturers Association, and 17 refers to the base of the motor. The size of flangemounting is 1.7 inches × 1.7 inches, about 42mm × 42mm. Therefore, NEMA17 stepper motor is often called 42 stepper motor.

II, appearance size and structural features

NEMA17 stepper motor  flange size standard is 42mm × 42mm, The shaft diameter is usually 5mm, and the shaft end is generally provided with a keyway or plane, which is convenient for close connection with transmission parts. The length and specifications are various, ranging from short to 23mm to long as 67mm, which can be selected according to actual torque requirements. Most of the shell materials are aluminum alloy, and the surface is anodized, which has good heat dissipation performance and can effectively prevent corrosion. The internal structure includes stator and rotor. Stator is wrapped with multiple sets of coils. Rotor is made of permanent magnet material. By controlling the on-off and direction of coil current, the motor can be made according to the angle and distance we want, accurate Rotation step by step.

III, technical parameters and performance indicators

The step angle of NEMA17 stepper motor is 1.8 °, means that it covers 1.8 ° in each step. It is mostly designed for two phases, with two sets of coils. Through introducing different phase currents into the two sets of coils, a rotating magnetic field is generated to drive the rotor to rotate. Stepper motor is generally driven by constant current, the power supply voltage depends on the driver, and the common system voltage is 12V or 24V. Its work current is generally between 0.4A-1.7A .  holding torque refers to the maximum torque that the motor can bear when it is powered but remains stationary. Generally, the range is 0.3 Nm-0.7Nm. The longer the machine body is, the larger the holding torque will be provided, which is suitable for applications requiring greater static resistance. The normal operating temperature range is-20°C-50°C, which is used beyond this temperature range, it will affect the performance and service life of the motor , high temperature resistant 17 series motor can run at 180°C at most .

IV, application fields and typical cases

in 3D printing equipment, NEMA17 stepper motor is used to accurately control the printing nozzle in X, Y, the movement in the z-axis direction can ensure the stable movement of the nozzle according to the preset path and realize high-quality model printing by virtue of its high positioning accuracy and moderate output matrix.

in CNC CNC machine tools, NEMA17 stepper motor is responsible for driving the movement of machine tool table and tool, its accurate step angle and stable operation performance, it can ensure the accuracy of the tool path in the processing process, thus realizing high-precision engraving of various complex patterns and shapes. NEMA17 stepper motor is small in size and moderate in torque. It is suitable for light equipment, small processing and desktop 3D printer, and can meet its precise and low-speed motion control requirements. However, due to its limited structure and power, the rated torque is usually only 0.5-2Nm, it is difficult to drive large heavy-duty equipment, forced use is easy to cause motor overheating, out of step or even equipment damage.

in the automatic production line, NEMA17 stepper motor is used for material transfer, sorting and other links, it can accurately transport different types of materials to the designated position through the start, stop and positioning of the conveyor belt. Its good controllability can make the production line run efficiently and stably, and improve the production efficiency and product quality.

among medical devices, NEMA17 stepper motor can play a role in the drive system of some small medical devices such as blood analyzer and microscope stage. In the microscope carrier table, it can accurately control the movement of the carrier table, which is convenient for doctors to observe different parts of the sample. Its characteristics of low noise and high precision meet the strict requirements of medical equipment on operation stability and operation accuracy.

in smart office equipment, such as printers and scanners, NEMA17 stepper motor can be used to control the movement of print head and scanner. In inkjet printer, the motor drives the print head to reciprocate in the width direction of the paper to achieve accurate inkjet printing and ensure clear and accurate text and images are printed.

V, suggestions for purchase and use

in terms of purchase, we must first define the requirements and determine the required torque, precision, speed and other parameters according to the actual application scenario; ensure that the selected motor is compatible with the existing drive system and control system. Different motors have different requirements on drive current and voltage, and it is necessary to select the appropriate driver according to the motor parameters, at the same time, whether the size of the motor can meet the requirements of the installation space of the equipment should be considered. In addition, you should carefully consult the specifications and technical documents of the motor to understand its detailed performance parameters, working characteristics and application cases. If necessary, you can consult the manufacturer for technical issues and obtain professional suggestions.

in terms of use, the first thing is to install correctly, strictly follow the motor installation instructions to ensure that the motor is firmly installed. The second is to reasonably set the current, voltage and other parameters of the driver according to the rated parameters of the motor and the actual application requirements. The third is to control the ambient temperature of the motor within the specified range as far as possible to avoid humid, dusty and corrosive gas environment. Finally, regular maintenance and inspection shall be conducted regularly to check whether the appearance of the motor is damaged, whether the connection part is loose, and whether there is abnormal noise and vibration during operation. At the same time, the electrical performance of the motor shall be tested, identify potential problems and maintain and replace them in time to prolong the service life of the motor.