Electric slides are the most commonly used standardized modules in automation equipment. Because there are many types of electric slides, in the selection process, if the selection is incorrect, it will bring various problems to the performance of the equipment and the advancement of the project. Therefore, the selection of electric sliding table is very critical.
1. Performance index of electric sliding table.
The performance indicators of the electric sliding table can be carried out from three aspects.
Accuracy characteristics of the electric sliding table: including repeated positioning accuracy, positioning accuracy, running parallelism, running straightness, backlash, etc.
The motion characteristics of the electric slide: handleable weight, torque resistance, running speed, acceleration, running noise, etc.
Comprehensive characteristics of electric slides: mean time between failures (MTBF)’, service life, refinement, load density, etc.
Mean time between failures (MTBF)
2. Selection steps of electric sliding table.
The selection of electric sliding table can refer to the following steps:
(1) Determine the use environment of the electric sliding table: according to the use environment, judge it as a general environment, a clean environment, or a harsh environment?
(2) Determine the installation direction of the electric slide. Determine whether the electric slide is installed horizontally, on the wall or vertically.
(3) Determine the load carried by the electric slide table.
(4) Calculate the speed and acceleration of the electric sliding table.
(5) Check the allowable torque of the electric sliding table: calculate the torque values in all directions in the static (uniform speed) state and in the acceleration and deceleration state: Ma, Mb, Mc.
(6) The accuracy level requirements of the electric sliding table: clarify the required repeated positioning accuracy, the requirements for the parallelism of walking, etc.
(7) Determine the motor installation style: the commonly used electric slide installation methods include direct connection type, the left side of the motor, the right side of the motor, and the bottom side of the motor, etc.
(8), electric slide travel limit switch mode.
(9) Determine the motor specification and power of the electric slide.
1. Determine the use environment
General environment? Clean environment? Harsh environment?
2. Determine the installation direction
Horizontal installation? Wall installation? Vertical installation?
3. Determine the weight of the haul
The body width series is preliminarily determined according to the carry able weight.
4. Calculate speed/acceleration
According to the beat requirements, calculate the required speed and acceleration.
5. Allow torque check
Calculate Ma Mb. Mc in resting and running states
6. Accuracy class
Determine the required repeatability, parallelism and other requirements.
7. Motor installation style
Determine the motor installation orientation.
8. Photoelectric switch style
Determine the photoelectric switch style
9. Determine the motor specifications
Determine the power and brand of the motor.
2. Misunderstandings in the selection of electric slides
The loadable weight of the electric slide is closely related to the speed, acceleration and torque values. The load cannot be simplified. The load weight and load moment values must be checked at the same time.
When the center of gravity of the load deviates from the center of the slide, the generated torque in all directions will act on the guide rail of the electric slide. Be sure to check the torque values.
The dynamic allowable moment (Ma, Mb, Mc) is generally the allowable moment corresponding to the linear motion unit 10000km. During acceleration and deceleration, additional acceleration torque will be generated.
Total torque force= static (uniform speed) torque + acceleration and deceleration additional torque.
Please refer to the following figure for the torque data: