Which is more accurate, screw execution or belt execution?

In terms of cost performance, cost and accuracy, screw transmission will be better.

1. Power system comparison

Figuratively speaking, the servo motor is equivalent to an eight-cylinder car and the stepping motor is equivalent to a four-cylinder car, so the horsepower of the servo motor is definitely larger than that of the stepping motor, which determines that the stepping motor is more suitable for small machines and the servo motor is more suitable for large machines.

2. Comparison of transmission media

High-precision ball screw has four characteristics: compared with sliding screw pair, the driving torque is1/3; Using ball motion, the starting torque is very small, and there will be no crawling phenomenon like sliding motion, which can ensure accurate micro-feed; No backlash, high rigidity; Ball screw has high movement efficiency and low calorific value, and can realize high-speed feed. PU timing belt is our common belt, which will stretch after being used for a long time and needs to be replaced frequently. This determines that the high-precision ball screw is more durable and stable than the PU synchronous belt, and it is more neutral after long-term work.

3. Stability comparison

Both feeders have good stability at first, but they are quite different after long-term use. PU synchronous belt is generally used on machines with mobile platforms. After long-term use, the belt will be deformed, and even the platform will tilt and slide, which will directly affect the alignment, accuracy and product quality of the machine. After long-term use, the oil stain on the surface of high-precision ball screw will slowly wear off, which will have a slight impact on the accuracy of the machine. At this time, it is good to apply some oil to the ball screw and slide rail. Just like a car, a car that has been used for a while will have better running-in performance than a car that has just been bought. The performance of our machine will reach its best in a few months. Of course, the stability of the machine will decline a little after one or two years of use, but it will not hinder the alignment, accuracy and product quality of the machine. Therefore, the universal lithography driven by screw is much better than that driven by PU synchronous belt.

4. Cost comparison

The cost ratio of servo motor and stepping motor is generally 5: 1. Generally, the market price of a better stepping motor is around 600 yuan, and the servo motor is around 3000 yuan. The cost of ball screw and PU synchronous belt is relatively high. A belt is usually several yuan or more, and a ball screw is usually hundreds or even thousands of yuan. Therefore, the cost of ball screw+servo motor will be at least 3000 yuan more than that of PU synchronous belt+stepping motor, which is why the price of the same machine will be so different after adopting different feed systems.

The above is the performance and cost comparison between belt drive universal printer and spiral drive universal printer. Generally speaking, as a long-term investment customer, I still recommend buying a universal flat-panel printer driven by a ball screw servo motor.