​Structural layout and characteristics of CNC lathe


The structure of a CNC lathe. A CNC lathe is also composed of a spindle box, a tool rest, a feed transmission system, a bed, a hydraulic system, a cooling system, a lubrication system, etc. Only the feed system of a CNC lathe is different from that of a horizontal lathe. There are fundamental differences in structure. The movement of the horizontal lathe spindle is transmitted to the tool rest through the wheel frame, feed box, and slide box to complete longitudinal and transverse feed movements. The CNC lathe uses a servo motor, which is transmitted to the slide plate and tool rest through the ball screw to complete the z-direction (longitudinal) and vertical (transverse) feed movements. CNC lathes also have various thread functions. The kinematic relationship between the spindle rotation and the tool holder movement is controlled by the CNC system. The CNC lathe spindle box is equipped with a pulse encoder, and the movement of the spindle is transmitted to the pulse encoder through the synchronous toothed belt. When the spindle rotates, the pulse encoder sends a detection pulse signal to the CNC system, so that the rotation of the spindle motor and the cutting feed of the tool holder maintain the kinematic relationship required for thread processing. That is, when the thread processing is completed, the spindle rotates once, and the tool holder Move the workpiece one lead in the z direction.

The structure of the CNC lathe. The structure of the spindle, tailstock and other components of the CNC lathe relative to the bed is basically the same as that of the horizontal lathe. However, the structure of the tool rest and guide rails has undergone fundamental changes. This is due to the structure of the tool rest and guide rails. Directly affects the function, structure and appearance of CNC lathes. In addition, CNC lathes are equipped with closed protective equipment. The layout of the bed and guide rails. There are four layout methods for the relative orientation of the CNC lathe bed guide rail and the horizontal plane. The horizontal lathe has good craftsmanship and is convenient for processing the guide rail surface. A horizontal lathe with a horizontally equipped tool holder can increase the movement speed of the tool holder and can generally be used in the layout of large CNC lathes or small precision CNC lathes. However, the space under the horizontal bed is small, making it difficult to move shoulders. From the structural scale point of view, the horizontal placement of the tool holder makes the lateral scale of the skateboard longer, thereby increasing the structural scale in the width direction of the machine tool. The layout method of a horizontal bed equipped with a tilted slide plate and equipped with a tilted guide rail guard. On the one hand, it has the characteristics of good craftsmanship of the horizontal bed; on the other hand, the size of the machine tool in the width direction is smaller than that of a horizontal bed equipped with a slide plate. And chip removal is convenient. The layout of a horizontal bed equipped with a tilted sliding plate and an inclined bed equipped with an inclined sliding plate is widely used by small and medium-sized CNC lathes. This is because these two layout methods are easy to remove chips, and the chips will not accumulate on the guide rails, and it is also convenient to install an automatic chip conveyor; it is easy to operate and easy to install a manipulator to achieve stand-alone automation; the machine tool occupies a small area and has a simple and beautiful appearance. , simply complete closed protection.

The tool holder of a CNC lathe is an important part of the machine tool. The tool holder is used to hold cutting tools. Therefore, its structure directly affects the cutting work and cutting efficiency of the machine tool. To a certain extent, the tool holder

Above, the structure and function of the tool holder reflect the planning and production level of CNC lathes. With the continuous development of CNC lathes, the structure of tool holders is constantly innovating, but overall it can be roughly divided into two types:

Categories. That is, the row-type tool holder and the turret-type tool holder. Some turning centers also use automatic tool changing equipment with tool magazines. Tool holder - generally used on small CNC lathes to place and clamp various tools

It is held on a movable sliding plate and can be actively positioned when changing tools. The turret tool holder is also called a tool turret or tool table, and it has two structures: vertical and horizontal. Equipped with multi-tool active positioning equipment,

The active tool changing action at the end of the machine is completed through the rotation, indexing and positioning of the turret head. The turret tool holder should have accurate indexing, reliable positioning, high repeatability, fast indexing speed, and clamping stability.

Well, to ensure the high precision and high power of CNC lathes. Some turret-type tool holders can not only achieve automatic positioning, but also transmit power. Nowadays, two-coordinate linkage lathes mostly use 12 stations.

There are also turret tool holders with 6 stations, 8 stations and 10 stations. There are two ways to lay out the turret tool holder on the machine tool: one is the turret used for processing disc parts

The other type is a turret-type tool holder, whose rotation axis is perpendicular to the spindle; the other is a turret-type tool holder used for processing shaft and disc parts, whose rotation axis is parallel to the spindle.

The bed of a four-coordinate controlled CNC lathe is equipped with two independent slide plates and a turret tool holder, so it is called a double-tool turret four-coordinate CNC lathe. During this period, the cutting feed of each tool holder

They are controlled separately, so the two tool holders can cut different parts of the same workpiece at the same time, which not only expands the processing range, but also improves the processing efficiency. The structure of the four-coordinate CNC lathe is complex and

It needs to be equipped with a specialized CNC system to control two independent tool holders, which is suitable for processing crankshafts, aircraft parts and other parts with complex shapes and large batches.