20mm NEMA8 linear hybrid stepper motor with run through lead screw shaft
This is NEMA8 (20mm size) hybrid stepper motor with a run-through shaft, as called as non-captive shaft.
Not like stepper motor with round shaft/D shaft, this run-through shaft is free to move upward and downward while spinning at the same this.
This is know as linear stepper motor, which can do linear movement.
The linear moving speed is determined by driving frequency and lead screw’s lead.
There is a manual nut on the back of motor, which can be used to rotate the motor manually when power off, or can be assembled with encoders for close loop system
|Drive voltage||5V DC|
|Number of phase||2 phases|
About lead screw
The lead screw used on linear hybrid stepper motor is in general trapezoidal lead screw.
For example for Tr3.5*P0.3*1N lead screw.
Tr means trapezoidal lead screw type
P0.3 means lead screw’s pitch is 0.3mm
1N means it’s single start lead screw.
Lead screw lead=start number*pitch
So for this specific lead screw, it’s 0.3mm lead.
Motor’s stepper angle of hybrid stepper motor is 1.8 degrees/step, which takes 200 steps to rotate one turn.
Step length is linear movement the motor makes, when it takes one single step.
For a 0.3mm lead screw, step length is 0.3mm/200 step=0.0015mm/step
Basic structure of NEMA stepper motors
Application of Hybrid stepper motor
Due to high resolution of hybrid stepper motor’s (200 or 400 steps per revolution), they are widely used for applications requiring high precision, such as:
Industrial control(CNC, automatic milling machine, textile machinery)
And other automatic systems requiring high precision control.
Customers should follow the principle of “selecting stepper motors first, then select driver based on existing stepper motor”
It is best not to use the full-step driving mode to drive a hybrid stepping motor, and the vibration is bigger under full-step driving.
Hybrid stepper motor is more suitable for low-speed occasions. We suggest the speed does not exceed 1000 rpm (6666PPS at 0.9 degrees), preferably between 1000-3000PPS (0.9 degrees), and it can be attached with a gearbox to lower it’s speed. The motor has high working efficiency and low noise at suitable frequency.
Due to historical reasons, only the motor with a nominal 12V voltage uses 12V. Other rated voltage on design drawing is not exactly the most suitable driving voltage for the motor. Customers should choose suitable driving voltage and suitable driver based on own requirement.
When the motor is used with high speed or large load, it generally does not start at the working speed directly. We suggest to gradually increases the frequency and speed. For two reasons: First, the motor does not lose steps, and second, it can reduce noise and improve the positioning accuracy.
The motor should not work in the vibration area(below 600 PPS ). If it must be used at slow speed, vibration problem could be reduced by changing the voltage, current or adding some damping.
When the motor works below 600PPS (0.9 degrees), it should be driven by small current, large inductance and low voltage.
For loads with a large moment of inertia, a large size motor should be selected.
When higher precision is required, it could be solved by adding gearbox, increasing the motor speed, or using subdivision driving. Also a 5-phase motor(unipolar motor) could be used, but the price of the entire system is relatively expensive, so it’s rarely used.
Stepper motor size:
We currently have 20mm(NEMA8), 28mm(NEMA11), 35mm(NEMA14), 42mm(NEMA17), 57mm(NEMA23), 86mm(NEMA34) hybrid stepper motors. We suggest to determine motor size first, then confirm other parameter, when you select a hybrid stepper motor.
Motor’s design can be adjusted based on customer’s requirement including:
Motor’s diameter: we have 6mm, 8mm, 10mm, 15mm and 20 mm diameter motor
Coil resistance/ rated voltage: coil resistance is adjustable, and with higher resistance, motor’s rated voltage is higher.
Bracket design/ lead screw length: if customer want the bracket to be longer/short, with special design such as mounting holes, it’s adjustable.
PCB + cables + connector: PCB’s design, cable length and connector pitch are all adjustable, they can be replaced into FPC if customers require.
If we have samples in stock, we can ship out samples in 3 days.
If we do not have samples in stock, we need to produce them, production time is about 20 calendar days.
For mass production, lead time depends on order quantity.
Payment method and payment terms
For samples, in general we accept Paypal or alibaba.
For mass production, we accept T/T payment.
For samples, we collect full payment before production.
For mass production, we can accept 50% pre-payment before production, and collect the rest 50% payment before shipment.
After we cooperate order more than 6 times, we could negotiate other payment terms such as A/S (after sight)
1.How long is the general delivery time for samples? How long is the delivery time for back-end large orders?
Sample order lead-time is about 15 days,mass quantity order lead -time is 25-30 days.
2. Do you accept custom services?
We accept products customize.including the motor parameter,lead wire type,out shaft etc.
3. Is it possible to add an encoder to this motor?
For this type motor, we can adding encoder on the motor wear cap.