Machining center is a NC machining equipment with tool magazine and automatic tool change function. A large number of machining tools and auxiliary tools are stored in the tool magazine, so that the machining center can call when performing different machining tasks. The capacity, structure and layout of the tool magazine play an important role in the design and function of the machining center.
The larger the magazine capacity, the better
When many enterprise bosses choose machining centers, they think that the larger the tool magazine is, the more complete the tools are, the better. In fact, it is not true, because most processing does not use too many tools. For example, drilling processing can complete 70% of the drilling processing with only 10 cutters; For milling, only 4 cutters are needed to complete 90% of milling. Therefore, usually, 14 cutters can complete more than 60% of the drilling and milling processing. If we consider some special processing, we need special tools. Even so, a total of 40 tools can complete more than 80% of the processing. However, the process of processing orders that most enterprises take over daily will generally not exceed this 80%.
Therefore, in most cases, the capacity of tool magazine will be 10 to 40, which can meet most or even all of the processing needs of general small and medium-sized enterprises. Blindly selecting and purchasing equipment with large tool magazine capacity will not only increase the purchase cost, but also occupy a lot of space and area, reduce the tool utilization rate, increase the complexity of the structure of the machining center, and cause a lot of unnecessary waste.
The form of tool magazine can be divided into linear tool magazine, disc tool magazine, chain tool magazine and other tool magazines according to different capacities and tool taking methods.
The simplest tool magazine - linear tool magazine
The cutters are arranged in a straight line in the magazine. Such a magazine has the simplest structure and the smallest capacity. Generally, it can only accommodate 8 to 12 cutters. Linear tool magazine is often used in automatic tool changing CNC lathes. In addition, it has also been used in CNC drilling machines. Because the capacity is too small, this form has been rarely used at present.
Disc magazine, the most complex tool magazine in classification
The layout of the tools in the disc magazine can be radial layout, axial layout, layout at a certain angle with the axis line of the magazine, or multi circle, multi-layer and multi row layout.
The radial layout will occupy a large space, and the position of the tool magazine is limited. This layout is generally placed on the upper end of the machine tool column, which has the advantages of short tool change time and simple structure of the whole tool change device. At present, axial layout is widely used. This layout is often placed on the side of the spindle, and the axis line of the magazine can be placed vertically or horizontally. The tool forms a certain angle with the axis line of the tool magazine, and the secondary angle is less than 90 degrees. This layout is umbrella shaped. The position of the tool magazine is relatively flexible, and there is no rigid arrangement. The tool magazine can be placed according to the overall layout requirements of the machine tool. However, in most cases, this kind of magazine is placed obliquely on the upper end of the column, so the capacity of the magazine should not be too large.
The layout of the above three disc tool magazine is commonly used, and the number of stored tools can reach 60 at most. If you want to further expand the capacity, you can use multi circle, multi-layer or multi row layout.
The most widely used tool magazine chain tool magazine
The tool magazine fixed on the ring link is called chain tool magazine, specifically, there are single row chain tool magazine and folding chain tool magazine. The latter can use extended chains to achieve greater tool storage. The chain type tool magazine is characterized by compact structure, high space utilization, large tool storage capacity, and the shape of the chain link can be adjusted according to the structure of the machining center, so the layout is relatively flexible. Therefore, the chain tool magazine is widely used in machining centers. When the number of props reaches 30 to 120, the tool magazine with this structure is usually used.
Other magazine
In addition to the above three common tool magazine forms, there are many other tool magazines, including single-sided and multi-sided lattice box tool magazines. The layout of the single-sided lattice box type magazine is extremely inflexible, requiring the magazine to be placed on the workbench. This layout is rarely used now. Relatively speaking, the multi-faceted lattice box tool magazine has a more compact structure and faster tool change speed, but the action of tool selection and tool change is too complex, and it is not often used in single machine machining centers. It is mostly used in the centralized tool supply system of flexible manufacturing systems.