Views: 0 Author: Leapion Publish Time: 2022-05-31 Origin: https://www.leapioncnc.com/
Today, Leapion will introduce how to choose magazine and tool.
The function of the tool magazine is to reserve a certain number of tools, which can be exchanged with the tools on the spindle through the manipulator. There are various types of tool magazines, such as disc magazines, chain magazines, etc. The form and capacity of the magazines should be determined according to the technological scope of the machine. In the disc tool magazine, the direction of the tool is in the same direction as the spindle. When changing the tool, the spindle box rises to a certain position, so that the tool on the spindle is aligned with the bottom position of the magazine, and the tool is clamped Hold, the spindle is under the control of CNC, release the tool handle, the disc tool magazine moves forward, pulls out the tool on the spindle, and then the magazine rotates the tool used in the next process to the position aligned with the spindle, the magazine Backward, insert the new tool into the spindle hole, the spindle clamps the tool holder, the spindle box is lowered to the working position, the tool change task is completed, and the next process is processed. The advantages of this tool changing device are simple structure, low cost, and good tool changing reliability; the disadvantage is that the tool changing time is long, and it is suitable for machining centers with small tool magazine capacity.
For machining centers that require a large tool magazine capacity, a chain tool magazine can be used. The chain tool magazine has a compact structure and a large tool magazine capacity. The shape of the chain ring can be made into various types according to the layout of the machine. Shape, the tool change position can also be protruded to facilitate tool change. When the number of tools needs to be increased, it is only necessary to increase the length of the chain, which brings convenience to the design and manufacture of the tool magazine.
There are many tools stored in the general tool magazine. Before each tool change, the tool must be selected. The commonly used tool selection methods include sequential tool selection and arbitrary tool selection. The tools are inserted into the tool holders of the magazine in turn according to the process requirements. The processing is to adjust the tools in sequence. When processing different workpieces, the order of the tools in the tool magazine must be re-adjusted. The advantage is that the drive and control of the magazine are relatively simple. Therefore, this method is suitable for automatic tool change of small and medium-sized CNC machines with large processing batches and small number of workpiece varieties.
With the development of numerical control system, most numerical control systems at present adopt the method of arbitrary tool selection, which is divided into three types: tool holder coding, tool coding and memory type.
Tool coding or tool holder coding requires a coding strip installed on the tool or holder for identification, which is generally coded according to the principle of binary coding. Tool coding The tool selection method adopts a special tool shank structure and codes each tool. Each tool has its own code, so the tool can be reused many times in different processes, the replaced tool does not need to be put back into the original tool seat, and the capacity of the magazine can be reduced accordingly.
However, each tool has a special coding ring, the length of the tool is lengthened, it is difficult to manufacture, and the structure of the magazine and the manipulator becomes complicated. The way of tool holder coding is that one tool only corresponds to one holder, and the tool taken out from one holder must be put back into the same holder, which is very troublesome to pick up and deliver the tool, and it takes a long time to change. At present, the memory method is widely used in machining centers. In this way, the number and the position of the tool holder in the magazine can be correspondingly stored in the PLC of the CNC system. No matter which holder the tool is placed in, the tool information is always stored in the PLC. The magazine is equipped with a position detection device, which can obtain the position information of each tool holder. This way the tool can be taken out and returned at will. There is also a mechanical origin on the magazine, so that the nearest tool is selected each time a tool is selected.