Types of CNC Drilling Machines

According to their layout and functional characteristics, CNC drilling machines can be divided into CNC vertical drilling machines, drilling centers, CNC printed circuit board drilling machines, CNC deep hole drilling machines and other large CNC drilling machines.
CNC vertical drilling machines
CNC vertical drilling machines are developed on the basis of ordinary vertical drilling machines. They can complete multiple processes such as drilling, expanding, reaming, tapping, etc., and are suitable for medium and small batch production of parts with certain precision requirements for the distance between holes.
CNC vertical drilling machines generally have two-coordinate CNC "cross" worktables. The processed parts are clamped on the worktable and can move in two coordinates (the left and right movement of the worktable is the x-coordinate, and the forward and backward movement of the worktable is the y-coordinate). The vertical movement (Z-coordinate) of the spindle or spindle box with the tool can be CNC or non-CNC. The former uses a 3-coordinate CNC system, while the latter can use a simpler 2-coordinate CNC system. The spindle speed change and tool replacement are not much different from ordinary vertical drilling machines, and are mostly manual. It is suitable for processing porous parts with high hole spacing accuracy. Its CNC system is generally a point control system (there is also a linear control CNC system), which is an economical CNC with a low price.
Drilling center
The drilling center is based on a 3-axis CNC vertical drilling machine with a turret tool magazine and an automatic tool change mechanism. It uses a spindle motor with stepless speed regulation to automatically change the spindle speed. It can perform drilling, expansion, reaming, countersinking, tapping and other hole processing processes, and can complete contour control milling with linear and circular interpolation.
Since most small and medium-sized parts generally require several tools to process (within 10 tools), adding an automatic tool changer and automatically changing the spindle speed at the same time can reduce labor intensity. Reducing tool change time not only improves the automation level of the machine tool, but also improves labor productivity.
Since the point control CNC system is replaced by a contour control CNC system, milling with linear and circular interpolation functions can be performed, which is more suitable for parts that are processed by drilling and milling.
According to the tool changing principle and machine tool structure, drilling centers are currently divided into single-spindle and multi-spindle types. The multi-spindle tool changing method is to arrange 6 or 8 spindles radially in the turret, and the spindle conversion and automatic tool change are realized by the rotation of the turret.
Since multiple spindles must be arranged in the turret, and there are main transmission, indexing, positioning and other mechanisms, the turret head structure is complex and difficult to process. In addition, due to size limitations, the spindle rigidity is affected to a certain extent, and the position repeatability accuracy between the spindles is not ideal.
Because multi-spindle drilling centers have some of the above problems, many manufacturers have developed single-spindle drilling centers. It automatically replaces tool holders with various tools on the same spindle to achieve automatic tool change, and adopts a turret tool magazine to overcome the shortcomings of multi-spindles. The following figure is a domestic single-spindle drilling center.

PCB CNC Drilling Machine
PCB CNC Drilling Machine is a special drilling machine tool specially used for processing PCB. Since the diameter of the holes on PCB is very small and the number is large, it is generally equipped with two, three or more high-speed drilling heads. The spindle speed can reach more than 20,000 revolutions. It is suitable for drilling holes on double-sided and multi-layer boards.
Other large CNC drilling machines
For some large parts, such as boilers, chemical containers, tube sheets and other parts, it is impossible to process them on general CNC vertical drilling machines and drilling centers. The outer dimensions of the parts can reach several square meters, and some of them have more than 2,000 holes. They should be processed by rocking CNC drilling machines or gantry or column-moving large CNC drilling machines.