Automatic lathe and its characteristics. CNC multi-spindle longitudinal turning machine. Production and processing of parts on automatic lathes

A lathe is called a special machine, the processing of parts on which is carried out without the participation of a worker. This type of equipment is more expensive than usual. However, it is considered more convenient to use. All operations on such machines are carried out automatically. The worker monitors only the loading of the workpieces and monitors the quality of the manufactured parts.

Varieties of machine tools

There are several types of such equipment. Parts can be manufactured on single-spindle or multi-spindle automatic machines. Structurally, they differ little. The only difference is that on equipment such as single-spindle automatic lathes, turning is performed using only one working tool. In the design of multi-spindle machines there are several. By type of workpiece, all automatic lathes are divided into:

• screw cutting;

• carousel;

• lobotocar;

• turning and milling;

• turning and revolving;

• longitudinal turning.

Screw cutting machines are used to perform all types of turning operations, carousel machines are used for processing large-sized workpieces. Lobotokarnye machines are used for turning cylindrical, frontal and conical products. Milling equipment is used for embossing. Revolving machines are used for the manufacture of parts of complex shape. We will talk in full detail about what longitudinal section machines are for and what are the features of their design.

Purpose of automatic lathes

As with conventional machines, this type of equipment performs such works as:

• longitudinal turning of cylindrical and stepped surfaces;

• external conical processing;

• slotting, machining of ends and ledges;

• boring holes;

• drilling;

• thread cutting;

• corrugation;

• shaped turning.

General design features

All lathes and semi-automatic machines, like conventional machines, are thus designed to remove certain parts of the workpiece during the rotation of the latter. By design, different types of this equipment can vary greatly. However, the basic features for most types are common. The design of any lathe includes: bed, front and rear headstock, carriage. The latter is designed to hold the tool and move it in the right direction. A special feed mechanism is responsible for this process.

On the front headstock of equipment such as automatic lathes, a spindle and a speed change mechanism are attached. It is fixed very firmly, as it can cause vibrations that are transmitted to the workpiece and reduce the quality of the finished part. The spindle in the headstock is fixed on bearings and is equipped with special clamping devices (hinges or chucks). It is driven by a separate electric motor through the gearbox.

Beds in lathes can be used different (inverted, V-shaped, flat). This structural element should be located as accurately as possible. Any deviations lead to a significant decrease in the quality of manufactured products.

The tailstock is used to support long workpieces during turning. It is usually located along the table and is fixed in the position most convenient for the manufacture of the part.

Lathes can be automated using a controller or a mechanical command device. This type of equipment differs from simple CNC machines in that the workpieces in this case are also automatically sent for processing. CNC such machines can be equipped additionally.

The difference between machines from conventional machines

Work on machines of this type, in this way, can be performed the same as on simple turning equipment. The difference lies in the fact that the turning of parts on automatic machines is carried out according to a strictly specified cycle. On a conventional machine, the worker, having finished the manufacture of one part, can immediately begin to grind another. The automatic changeover of the cams takes several hours, and preparation for it takes several days.

Scope of use

Lathes have much greater productivity than conventional machines. Since their frequent changes lead to the loss of production time, this equipment is usually used in large-scale production. In addition, since such equipment is quite expensive, it is advisable to use it only if there is a need to manufacture parts of very complex shapes with a large number of transitions. Very often, enterprises use highly specialized machines of this type, designed to produce a single part or a small group of products.

Multi-spindle automatic machines

This kind of automatic turning equipment is used in enterprises for the mass production of parts of various shapes and sizes. This distinguishes these machines from single-spindle machines, which are mainly used for the production of serial identical products. There are two varieties of such machines:

• Horizontal The main advantage of such machines is the ease of loading the source material. Therefore, they are used where continuous wire feed is used.

• Vertical . Plus multi-spindle machines of this variety are small sizes. Indoor equipment of this type does not take up too much.

A multi-spindle automatic lathe can sometimes be used in small-scale production. But only if equipped with CNC.

Longitudinal turning machines

Equipment of this type has recently become increasingly popular. Used longitudinal turning machines for the manufacture of mainly small parts of a very complex shape. A distinctive feature of their design is the presence of a movable headstock. The type of clamp in such machines uses a collet. The counter spindle in longitudinal turning machines is mounted on high-precision linear guides.

A feature of the machines of this variety, among other things, are small dimensions. Their working area is also not too extensive. Automatic machines of this type usually operate at very high speeds.

A longitudinal turning lathe can be used in both mass and serial production of parts. Most often, equipment of this type is used in the optical, electrical and instrument-making industries. Cutters in such machines are installed in calipers and move only in the horizontal direction. In the production, longitudinal turning machines are used, both single-spindle and multi-spindle.

A longitudinal turning lathe is designed to perform operations such as:

• grinding of steps;

• grooving and cones;

• boring of shallow holes;

• processing of shaped surfaces;

• threading internal and external;

• hole deployment ;

• knurling of external surfaces;

• milling slotted screws;

• drilling.

The surfaces on machines of this type can be processed very different: conical, cylindrical, stepped, etc. To expand the capabilities of longitudinal turning machines, various additional devices are used. For example, the use of gear levers reduces wear on the cams and pusher shoes.

Design features of longitudinal turning machines

The headstock for such machines is fixed on the upper plane of the bed. Ahead on it there is a special platform designed to install additional devices. A vertical caliper is installed on its upper plane, and a swinging stop on the back. Equipment such as a lathe is controlled by a system of cams and camshafts mounted in a bed.

Main advantages

The advantages of longitudinal turning machines primarily include:

• the possibility of obtaining shaped and conical surfaces when using prismatic cutters;

• smooth quality surface of finished products;

• the possibility of milling both along the axis of the part and across it;

• the ability to roll small numbers, signs and letters.

Processing of parts on automatic lathes of this type can be carried out with maximum accuracy.

Principle of operation

During processing, the source material on such machines is given not only rotational motion, as on conventional ones, but also translational - along the axis. The cutters themselves in equipment such as turning bar automatic machines of longitudinal turning, move only perpendicular to the bar. The radial forces arising during processing are perceived by the rest. This allows you to eliminate all kinds of vibrations and deflections and, accordingly, to ensure high precision processing.

The cycle of movement of the headstock and tools in machine tools for longitudinal turning is set by cams tuned specifically for this particular part. The latter are mounted on a special shaft, the number of revolutions of which can vary, including at a constant spindle speed.

Maintenance of automatic turning machines

In operation, machines of this type are simple. However, of course, they require some care. For example, in order for the cooling system to function smoothly, it is necessary to periodically change the oil in it. It is also recommended that you rinse the fluid bath monthly. The design of the cooling system also includes a filter that should be cleaned at the same frequency. These recommendations should be followed. Repairing a lathe is expensive.

CNC machines

As already mentioned, machines designed for the manufacture of metal parts can optionally be equipped with CNC. Such control systems are usually used if the automatic lathe is designed to produce parts in serial or small-scale production. The software used in the CNC allows you to:

• automate the processing process;

• improve the quality of the workpiece;

• significantly reduce the setup time of the machine.

All kinds of drives and converters in the CNC are digital. They are electric motors operating either from alternating or direct current. When using the CNC, special sensors are built into the kinematic diagram of the machine. The working tool in machines equipped with CNC is used as durable as possible, since they operate with very high speed and productivity. The design of the base of such machines should be extremely rigid.

CNC multi-spindle longitudinal turning machine

Actually, the numerical software itself is nothing more than a computer system with special software installed on it that controls the drives of the machine. Typically, the standard equipment for automatic machines equipped with CNC is as follows:

• spindle;

• cooling system;

• counter spindle;

• lighting for the working area;

• Workpiece ejection sensor

• bushing variable;

• a special device designed to accept finished products;

• tools for external and internal turning;

• front and cross drive tools;

• CNC system itself.

Simple lathes, multi-spindle longitudinal turning without CNC, are mainly used for multi-series production of a large number of various kinds of small parts, most often long and small sections, of complex shape. The latter usually serve as structural elements of modern medical and laboratory equipment, electronics, watches, etc.

The installation of CNC on such machines also allows the production of a large number of products, but not of the same, but of different shapes (that is, in small batches). Ordinary machines are most often configured to produce a particular part and only once. The fact is that the mechanical “reprogramming” of equipment of this type, as already mentioned, is an extremely complicated and lengthy procedure. Idle production during readjustment very much affects its profitability. Therefore, the use of conventional machines for the production of small batches of parts of various shapes is considered impractical.

The CNC installation helps to solve this problem and combine the advantages of the machine with the possibility of expanding the range of manufactured products. If the machine has a numerical control system, it can be reconfigured very quickly. For example, the cutting insert is changed directly on the machine itself without removing the holder. To change the rotation speed of the tools and the order of their work, you only need to enter certain values ​​in the program window on the CNC computer.

Production of parts on CNC longitudinal turning lathes: features

The participation of the worker when using machines of this type is minimized. All that is required from a specialist is to monitor the uninterrupted operation of the equipment. Of course, the quality of products in this case directly depends on the accuracy of the machine settings. Therefore, CNC programs should be as thought out as possible.

The main task of those industries that use equipment such as a longitudinal turning CNC machine is to produce parts with precisely specified parameters and at the same time low cost. The rods used as starting material on such machines usually have a geometrically not very calibrated shape (even calibrated). Moreover, all errors and inaccuracies can easily be transmitted to the finished part. Indeed, working tools, of course, cannot change their position or rotation speed arbitrarily without human intervention. This feature of cutting on automatic machines is called “heredity” and is the main problem of technical programmers of enterprises. It is usually solved by reducing the speed of the processing modes along the entire length of the cutting. Which, of course, leads to an increase in the cost of production due to increased time costs.

Meanwhile, it is possible to get rid of “heredity” with minimal losses using special modern CNC application programs developed taking into account the dynamic characteristics of the processing system that determine it. Their application allows you to assign the most accurate cutting mode with a reduction in time loss by more than two times.

Top brands

Thus, the correct adjustment of the machine for longitudinal turning using CNC programs allows you to make the production of small parts as cost-effective as possible. But of course, only if the equipment itself is of high quality. Repair of CNC longitudinal turning machines is complicated, expensive and time-consuming. Therefore, the choice of such machines is a very serious and responsible matter.

When buying equipment such as automatic lathes, you should first pay attention to its manufacturer. For example, CNC multi-spindle longitudinal turning machines of the following brands have earned good reviews:

• Tornos Series MultiSwiss.

• LA155F30.

• HJM SQC38.

Tornos Assault Rifles

The advantages of the MultiSwiss series are primarily high productivity and a relatively simple design. The Tornos multi-spindle automatic lathe is quite easily and quickly set up and re-set. In order to work on such a machine, you do not need to be an expert on multi-spindle machines. Management is done entirely through CNC. Technical characteristics of machines of this line are presented in the table.

Models LA155F30

Three-spindle automatic lathes of this brand belong to the accuracy class “B”.The main advantages of the LA155F30 machines are reliability and a long service life. Even after prolonged use, these machines allow you to process parts with maximum precision. In addition, the LA155F30 machines are not very high cost and maintainability.

Characteristics of automatic lathes of this manufacturer are as follows:

• diameter of the processed bar min / max - 6/16 mm;

• the maximum length of the product is 160 mm;

• rotation speed of the main spindle - 80-8000 rpm;

• electric motor power - 5.5 kW;

• machine weight - 2270 kg;

• — 56009001720 .

HJM SQC38

. ( ). HJM SQC38.

Conclusion

Thus, modern CNC longitudinal turning lathes - the equipment is very convenient, efficient and, in most cases, reliable. The most important thing in its operation is to use the most thoughtful software. This will increase the profitability of production and produce quality products with accurate dimensions.