1. Definition

Step motor is a kind of special motor which can convert the electric pulse signal into corresponding angular displacement or linear displacement. A step motor and its matching driver make up a set of step motor system. Every time an electric pulse signal is input to the motor, the motor will rotate an angle. Its movement form is stepping type, so it is called step motor.

2. Features

1. High resolution and high accuracy positioning

Under the control of pulse signal, the angular displacement output is proportional to the number of input pulses, so as to realize the accuracy operation with the inherent step angle as the unit. The step distance error will not accumulate, and it is less affected by external conditions (such as voltage fluctuation, temperature change, etc.). Taking the 1.8°step angle motor as an example, its resolution per rotation can reach 1/200 (i.e. 1.8°/ 360°), 1 /400, and the accuracy of each step error can be controlled within ± 5%. If micro step subdivision drive is adopted, can achieved higher resolution and higher accuracy.

2. Simple system structure

Under the function of driver, step motor can convert digital pulse signal into angular displacement or linear displacement directly without motor speed or position detector, and can operate correctly according to pulse command.
3. Good performance control

The speed of the motor is synchronous with the frequency of the control pulse, so the speed of the motor can be adjusted in a wide range by changing the frequency of the control pulse. By controlling the pulse, we can get very low speed and high torque directly without the transition of gear reducer, so as to avoid the power loss and the influence of motion accuracy, and can quickly controllable starting, stop, reversion and shift.

4. With self-locked force

When the power supply is stopped, there is still a positioning torque. After the shutdown, it still keeps the state of power on for the winding. It has the self-locked ability and can keep the stop position without the brake system.

5. Longer use life

Using the electronic commutation, without carbon brush and commutator for mechanical friction, thus reducing friction and increasing the use life of the motor.

3. Application field

Based on the above features, step motor is widely used in various digital management motion control applications, such as printers, stage lights, ATM machines, security monitoring, industrial equipment, medical, textile machinery, automobile industry and other products and fields.

4. Basic Structure of step Motor

Installation instructions

1Social responsibility.Do not disassemble the motor.

2. The air gap between the stator and rotor of this kind of motor is very small. Do not knock the motor surface with heavy objects or make the motor fall to the ground.

3. Please select the appropriate mounting method (screw and penetration), as shown in the following figure;

4. Select appropriate thickness of mounting plate to ensure mounting strength, Refer to the following table:

5. Working Principle

According to the external pulse, the step motor driver controls the winding of the step motor to be electrified in a certain time sequence, forward or reverse direction through the internal logic circuit, so as to make the motor run. Take the two-phase 1.8°step motor as an example:

1. According to the way of winding arrangements, there are generally two kinds of motors: four leads (bipolar) motor and six leads (Unipolar) motor.

For four leads (bipolar) motor, the direction of power on of its winding shall be in the order of: AB-BC-CD-DA four states cycle by cycle for on-off change. Each time of change, the motor runs one step, i.e. rotates 1.8 °.

four leads (bipolar)

For six leads (Unipolar) motor, the direction of power on of its winding shall be in the order of: OA-OB-OC-OD four states cycle by cycle for on-off change. Each time of change, the motor runs one step, i.e. rotates 1.8 °.

four leads (bipolar)

For six leads (Unipolar) motor, the direction of power on of its winding shall be in the order of: OA-OB-OC-OD four states cycle by cycle for on-off change. Each time of change, the motor runs one step, i.e. rotates 1.8 °.

six leads (Unipolar)

2. Phase Order Diagram and Wiring Diagram

2.1 four leads (bipolar)

2.2 six leads (Unipolar)

3. General Characteristics

4. Naming Rule

BJ  Y  Z  42  D  15 - 01  V  01

① ② ③  ④ ⑤  ⑥   ⑦  ⑧ ⑨

① Step motor type

hybrid：BJ 

permanent magnetic：PM

② Shape

Y：roundness

If there is no identification, it means the shape is square;

Just for the BJ motor, there is no logo on PM motor

③ Z：with gearbox

If there is no identification, it means it is without gearbox

④ Seat No.:overall dimension (mm), roundness means the outer diameter(mm)

⑤ Stepping angle

For BJ: C:0.9°；D:1.8°；E:0.6°；F:1.2°
G:3.6°；H:3.75°；K:5.625°
For PM: L:11.25°；P:15°；Q:0.72°；R:7.5°

⑥ Stator thickness：mm  

⑦ Performance No.：01～99

Show the performance parameters of motor, such as current, torque and ect.

⑧ Motor polarity

N: unipolar and single out of shaft
M: unipolar and double out of shaft
V: bipolar and single out of shaft
W: bipolar and double out of shaft

⑨ Mechanical specification：01～99

Show the motor shaft extension, lead wire, screw and etc. mechanical parameters