Structural layout and characteristics of CNC lathe

CNC lathes are also composed of spindle box, tool rest, feed transmission system, bed, hydraulic system, cooling system, smoothing system and other components. Only the feed system of CNC lathes is essentially different from the horizontal lathe in the structure of the feed system. The movement of the horizontal lathe spindle is transmitted to the tool rest through the pulley frame, feed box and sliding box to complete longitudinal and transverse feed movements. CNC lathes use servo motors to complete z (longitudinal) and azimuth (transverse) feed movements through ball screws to the slide plate and tool rest. CNC lathes also have various thread functions, and the kinematic connection 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 a 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 connection required for thread processing. That is, when the thread processing is completed, the spindle rotates and the tool holder moves the workpiece to the guide.

The layout of CNC lathe spindle, tailstock and other components relative to the bed is common with the horizontal lathe base. The layout of the tool rest and guide rails changes the base. This is because the layout of the tool rest and guide rails directly affects the function, structure and appearance of the CNC lathe. In addition, CNC lathes are also equipped with enclosed protective equipment. Bed and track layout. There are four ways to arrange the relative orientation of the CNC lathe bed guide rails and the horizontal plane. The horizontal bed offers good manufacturability and easy machining of the guide surface. The horizontal equipment tool gun used in the horizontal lathe can increase the moving speed of the tool holder, and can generally be used in the layout of large CNC lathes or small precision CNC lathes. However, the small space in the lower part of the horizontal bed makes removal of debris difficult. From the perspective of structural scale, the horizontal placement of the tool holder lengthens the lateral scale of the slider, thereby increasing the structural scale of the lathe in the width direction. The horizontal bed layout is equipped with inclined slide plates and inclined rail baffles. On the one hand, the horizontal lathe has the characteristics of good craftsmanship; on the other hand, the width of the lathe is smaller than the width of the horizontal equipment slide, and chip removal is easy. The layout of the inclined slide horizontal lathe and the inclined slide bed has been widely used in small and medium-sized CNC lathes. This is because the two layout methods are easy to remove chips, and the chips will not accumulate on the guide rails, which also facilitates the equipment to actively remove chips; the operation is simple, the equipment is simple to operate, and can complete the initiative of a single machine; the machine occupies a small area, has a simple and beautiful appearance, and is easy to seal and protect.

The tool holder of CNC lathe islatheAn important part of the tool holder, the tool holder is used to clamp the tool, so its structure directly affects the cutting force of the lathe. The structure and function of the tool holder reflect the planning and production level of the CNC lathe to a certain extent. With the continuous development of CNC lathes, the tool rest structure is constantly innovating, but generally it can be roughly divided into two categories, namely, row tool rest and turret tool rest. Some turning centers also use active tool changing equipment with tool magazines. The running tool rest is generally used in small CNC lathes. Various tools are placed and clamped on the movable sliding plate, and active positioning can be completed when changing tools. The tool holder is also called the tool tower or the tool table, and it has two structural forms: vertical and horizontal. Multi-tool position active positioning equipment is used to complete the active tool changing action of the lathe through the rotation, indexing and positioning of the tool holder. The tool holder should be positioned accurately and reliably, with high repeat positioning accuracy, fast rotation speed, and good clamping to ensure the high precision and power of the CNC lathe. Some tool holders can not only complete active positioning, but also transmit power. Nowadays, two-coordinate linkage lathes use 12-station turret tool holders, as well as 6-station, 8-station, and 10-station turret tool holders. There are two ways to arrange the turret tool holder on the lathe: one is the turret tool holder used for processing disc parts. The axis of rotation is perpendicular to the spindle; the other is a turret tool holder used for machining shafts and disc parts, whose axis of rotation is parallel to the spindle.

The bed equipment of the four-coordinate CNC lathe has two independent slide plates and tool turrets, so it is called a double-tool turret four-coordinate CNC lathe. At the same time, the cutting feed of each tool holder is controlled independently, so the two tool holders can cut different parts of the same workpiece together, which not only expands the processing scale, but also improves the processing capacity. The four-coordinate CNC lathe has a complex structure and requires a specialized CNC system to control two independent tool holders. It is suitable for processing crankshafts, aircraft parts and other parts with messy shapes and large batches.