There are many types of motors used in the indexer. Under normal circumstances, ordinary geared motors can meet the requirements of use. According to the designer's application habits and the special needs of automation design, the application of servo motors is also more common.
The indexer uses a servo motor, which mainly combines the precise positioning of the servo motor and the characteristics of the indexer torque, load and stability. In principle, the indexer belongs to the reducer of the servo motor, with a 360-degree driving angle and stopping at any point. The main concern of the servo motor drive indexer is the reset problem of the servo motor.
The reset method of the servo motor briefly summarizes a few points for your reference. The main purpose of using the servo motor is to ensure that the accuracy reaches a higher level. Therefore, when selecting the operation method, it should be based on the accuracy parameters and actual requirements. Some servo motors can automatically reset the origin. For example, it can be completed by the upper computer in cooperation with the servo. In summary, the principle of origin reset is basically the following:
1. The servo motor in the rotating state will decelerate and stop immediately when the induction sheet passes the origin, that is, when it touches the origin switch. This method of returning to the origin does not matter whether you choose a mechanical proximity switch or a light sensor switch. The accuracy is not very precise, because it is greatly affected by factors such as temperature and power fluctuations, which will cause the signal response time to be different every time. The motor runs at high speed to the process of sudden deceleration and stop after the origin. The difference in returning to the origin is above the silk level.
2. Another method is to directly look for the Z-phase signal of the encoder when the motor returns to the origin. When there is a Z-phase signal, the motor will decelerate and stop immediately. This kind of reset method is generally applied to the rotating shaft, and the reset speed is not high, and the accuracy is not high.
Third, there is another method that is most accurate, most of which are applied to CNC machine tools. The servo motor finds the origin switch at the first stage of high speed. When passing the origin switch signal, the motor immediately finds the Z phase of the motor at the second stage of speed. Signal, the first Z-phase signal must be on the origin block (the origin block of high-end CNC machine tools and central machines is mechanical and not inductive, and its length must be greater than one revolution of the motor to be converted into a straight line The length of the distance). After finding the first Z-phase signal, one way is to return to the origin before the block, and the other is to return to the origin after the block (it is safer to return to the origin before the block, and it is often used in European machinery. After returning to the origin, the work schedule will be longer, and the Japanese ones are more used). Take recovery after the block as an example. After finding the first Z-phase signal on the block, the servo motor will continue to rotate in the same direction to find the first Z-phase signal after leaving the block. Generally, this is what we call the real The origin, but because sometimes this point is just in the middle of the origin stop, it is prone to malfunction. You can set an offset under the premise of ensuring accuracy.
The above summarizes the reset method of the indexer using the servo motor, which can be used according to actual needs. The use of the servo motor will make the intermittent movement and stop more free and convenient without considering the cost.
