Table. Characteristics of some four-sided machines (characteristics - selling company, model, number of spindles, width of the workpiece being processed, height of the workpiece being processed, minimum length of the workpiece, spindle diameter, rotation speed, feed speed, loading table length, presence of a jointing support, motor power 1 and 4 spindles, motor power 2 and 3 spindles, the presence of a molding support, possible positions of the molding support, the power of the molding support motor, the power of the feed motor, the power of the traverse lifting motor, the total power of the machine motors, the dimensions of the machine, the weight of the base machine, the manufacturer is BZDS S23-4, Winner, Nortec, Gau Jing Machinery Industrial Co. Ltd GA-623H, Nortec, Machinery Industrial Co. Ltd GN-6S23, Griggio S.p.A. G 240/6, BZDS C25-5a Pro, SCM Group Superset NT Plus, High Point M-180, High Point MX-180/5, Ledinek Superles 4V-S150, REX Bigmaster 310-K, SCM Group Topset Master, REX Timbermaster Type U-41-K, MIDA Alfa-500)
Figure 1. Diagrams of feed mechanisms
Figure 2. Scheme of the cardan drive of the feed rollers using worm gears
Figure 3. Options for spindle placement in four-sided machines
See the table and figures in
And the quality of the processed parts largely depends on how uniform this movement is.
Feed mechanisms on four-sided machines
The feed mechanisms of four-sided machines refer to devices with a frictional connection between the workpiece and the elements that feed it. The movement of workpieces occurs due to the adhesion of their surface to the moving working elements of the feed conveyor. In this case, resistance in the form of frictional forces applied to them and longitudinal components of cutting forces is overcome.
In four-sided machines, concentrated feed mechanisms of three types were and are used: tracked, roller-tracked, roller - and distributed - roller (Fig. 1).
Tracked feed mechanisms are distinguished by their reliable grip of workpieces moving along the table, which eliminates their slipping, and the uniform distribution of vertical force, which reduces the straightening of warped workpieces. Such mechanisms are used for feeding short workpieces (for example, in domestic machines of the PARK-8 and PARK-9 models, designed for processing parquet staves) and in many modern four-sided machines based on double-sided planer-thicknessers - in the area of the jointer support.
Roller-caterpillar mechanisms are also distinguished by reliable grip and high feed force of workpieces. They are used primarily in machines for processing heavy workpieces with large cross-sections, for example, wall beams.
Roller machines, consisting of rollers (rollers are a pair of parallel drive shafts rotating towards each other), were originally used in four-sided machines. These mechanisms are distinguished by their simple design, reliability and low sensitivity to differences in thickness of the workpieces being advanced.
A common disadvantage of concentrated feed mechanisms of all three named types is the advancement of short workpieces end to end; with obliquely cut ends, workpieces can be squeezed to the side and upward, which leads to the need to increase the force of the upper and side clamps in the machine, leading to an increase in the required feed force.
Therefore, the design of most four-sided machines produced today uses a distributed feed mechanism in the form of a set of drive rollers located one behind the other along the entire length of the work table.
The first four-sided machine with such a distributed feed mechanism was introduced in 1960 by the German company Harbs, and today the vast majority of four-sided machines are equipped with them. The advantage of the roller mechanism is the ability to feed workpieces with an inter-end gap and process only one workpiece, which, without being pushed by others following it, is freely carried by drive rollers through the entire machine. Moreover, even when feeding workpieces end to end, the last loaded workpiece does not remain clamped in the machine.
The rollers of such a feed mechanism are installed on a single beam on swinging arms and at the same time play the role of upper clamps. In older machine models, these rollers were pressed against the workpieces by springs, but today pneumatic cylinders are used for these purposes. The beam is lifted along with all the rollers and clamps for adjustment to the processing size using a motorized drive, which also allows free access to the machine’s work table and its spindles for inspection and replacement of cutters.
The working surface of the feed rollers in machines is corrugated. The drive rollers installed behind the finishing cutter are coated with a layer of wear-resistant plastic.
Feed drive on four-sided machines
Rice. 2. Scheme of the cardan drive of the feed rollers with
using worm gears:
1 - beam;
2 - swinging lever;
3 - feed roller;
4 - feed roller spindle;
5 - axis of rotation of gearbox worms;
6 - worm gearbox;
7 - cardan shaft;
8 - machine desktop;
9 - guide ruler
Initially, the drive for rotation of the rollers of such feed mechanisms was carried out from common shaft, passing through the entire lifting beam, through bevel gears and chain drives.
But in 1970, the German company Gubisch developed a four-sided longitudinal milling machine
Maud. GN14, in which the cardan drive of the feed rollers was first used, which is used today in the designs of almost all similar machines. In such a drive, each of the feed rollers is connected through a cardan transmission to the output shaft of its worm gearbox, and the worms of all these gearboxes located on the same axis are connected by couplings and rotate simultaneously by one drive (Fig. 2), which is also mounted on the beam and rises with it .
Electric motors with variators of various designs were initially used as such a drive to rotate the rollers, providing stepless control of the feed speed. In modern machines, instead of variators, frequency control of the rotation speed of the electric motor of the feed mechanism is used using electronic converters.
Supports on four-sided machines
Any four-sided machine is equipped with at least four supports: horizontal (lower and upper) and vertical (left and right). In this case, the left calipers can be tilted. In the so-called moulders, an additional universal support is used - moulder.
For the sake of unification, each equipment manufacturer tries to make all these calipers the same. However, their design is significantly influenced by the need for adjustment movements. Thus, for the lower and right-hand feed spindles, radial adjustment is required, and its value is minimal, since it is only necessary to regulate the allowance removed by the cutter installed on them. At the same time, all left and upper spindles, when adjusted to the size of the workpiece being processed, must move within significant limits. All spindles usually also have the ability to move axially to adjust the position of the profile cutters.
Depending on the design developed by the machine manufacturer, the spindle is either an electric motor shaft (motor spindles) or a shaft mounted in bearings and driven into rotation by an electric motor through a belt drive. In the simplest and cheapest machines, one electric motor can rotate two vertical spindles simultaneously.
To transmit the rotation of the electric motor to the spindle, outdated models use V-belts, and in modern ones - thin synthetic ones.
The accuracy and rigidity of spindles is largely determined by the bearings in which they are installed. Many manufacturers use conventional bearings to reduce the cost of their machines, while expensive and high-quality ones use high-precision bearings.
It is believed that the use of machines with motor spindles is ineffective, since when replacing bearings in them, the rotor balance may be disrupted, which can lead to a decrease in the quality of processing. In addition, in belt-driven calipers, the belt serves as a damper, which prevents engine overload; Replacing it in case of failure will cost less than replacing the motor spindle.
To carry out adjustment movements, the calipers are mounted on dovetail guides or on parallel rolling pins. The movement of the supports along them is carried out by means of a “screw-nut” pair, rotated manually, with position control on a ruler with a vernier scale, or, in machines equipped with electronic system controls controlled by servomotors.
Moulder support for four-sided machine
This name arose from the concept of “kalevka” - a profile cut on the edge of a workpiece. A certain Armin Berner designed his first molding machine in Germany in 1920. And in 1954, the German company Weinig announced that it had received a patent for a multi-purpose four-sided machine with a molding slide that could be rearranged into different positions.
Such a support, depending on the design and model of the four-sided machine, can work in relation to the workpiece only from below, below and left, below and above, below and right, as well as below, above, left, right, or tilt at any angle.
The choice of technological capabilities of this support depends on the cross-sectional profiles of the parts produced by the company.
In most cases, molding supports at domestic enterprises are usually used for making a longitudinal recess on the underside of a machined part, for example, a platband, or for longitudinal cutting of milled blanks into narrow parts.
There is one more nuance: when choosing a machine, many production workers do not even think about the required power of this spindle, which leads to errors when processing parts. Thus, for simplicity of calculations, it is believed that when cutting with saws, making one cut requires engine power at the rate of 1 kW per 1 cm of workpiece thickness. That is, if a molding spindle is used to cut a 40 mm thick workpiece into three parts (with two saws), then the power of its engine must be at least 8 kW.
Power of other spindles on four-sided machines
If you do a simple analysis commercial offers on four-sided machines transferred by our machine tool trading companies to their potential buyers, then it turns out that the drive power of the spindles in this equipment is for some reason very often the same.
At the same time, the first lower cutter in the machine, which creates the basis for further processing of the part, removes a rather small allowance from the workpiece, and the required power of its drive is lower than what sellers offer. The power of the electric motor of the right cutter may also be insufficient, since it removes the allowance on the edge of the workpiece, which is always narrower than the largest width of the face.
The most powerful of all of these should be the drive of the upper horizontal cutter, which removes the increased allowance, which includes all the inaccuracies in the dimensions of the workpiece in thickness and width. Experience has shown that its engine power should be at least 11 kW. Moreover, this may not be enough if deep profiles are to be processed.
Lack of power in at least one spindle leads to the need to reduce the feed speed, which reduces the productivity of the machine.
Composition and arrangement of spindles of four-sided machines
In Fig. 3 shows some of the examples possible options mutual arrangement of spindles in four-sided machines. Manufacturers must select them in advance, before purchasing a machine, based on the required profile of the workpiece.
So, with the arrangement of the spindles shown in Fig. 3.1, it is possible to process parts with a rectangular profile or shallow profiling on four sides. The composition of the spindles shown in Fig. 3.2 makes it possible to mill a deep profile on the bottom surface of the part, and the spindle configuration shown in Fig. 3.3, - on the right (feed) edge.
If the composition of the machine components corresponds to that shown on
rice. 3.4, with the help of a molding support placed in various positions, it is possible to make deep profiles on all surfaces of the part and carry out its longitudinal cutting.
An additional lower spindle, as in the diagram shown in Fig. 3.5, makes it possible, for example, when jointing using a comb work table, to level the surface of the lower surface of the part and mill a profile on it using a molding spindle.
To sample a deep profile along the left edge and other surfaces of the part, additional vertical and molding spindles are used (diagram 3.6).
The arrangement of the spindles, corresponding to diagram 3.7, makes it possible to obtain U-shaped profiles, and that shown in diagram 3.8 - H-shaped ones.
The arrangement of spindles shown in Fig. 3.9, makes it possible to mill K-shaped profiles, and the diagram shown in Fig. 3.10, - even more complex, with additional longitudinal grooves.
On machines in which the spindles are located in accordance with the diagrams in Fig. 3.11 and 3.12, it is possible to obtain X-shaped profiles.
The spindles can be sequentially arranged in a different order, for example, in one that allows the allowance removed when forming the profile to be distributed among two or even three cutters. In addition, some profiles cannot be obtained without tilting at least one spindle.
Therefore, leading machine tool manufacturers, at the request of a particular consumer, can produce four-sided machines that have ten or more spindles. Today, machines with non-standard spindle arrangements are often found on the market for refurbished, used equipment.
Noise from four-sided machines
In many countries, the maximum permissible noise level in the workplace is legally set at 85 decibels (dB). Where noise levels exceed this value, protective equipment must be used. In fact, 85 dB is limit level noise, the impact of which on a person can last eight hours without damage to hearing. An increase in this noise level by 3 dB corresponds to a doubling of the intensity of exposure and a halving of the permissible time of exposure to sound. At a level of 88 dB, the permissible exposure time will be four hours, at 91 dB - two hours, etc. This means that the ear can tolerate noise of 110 dB for only a few minutes.
But this noise level is typical for all working four-sided machines. And even the presence of noise-absorbing casings on the equipment, which, as a rule, are open at the rear of the machine and have a decorative rather than protective purpose, does not help to reduce it. Therefore, such machines in production should be placed in a special soundproof cabin (Fig. 4), and machine operators must wear antiphons while working.
Four-sided machines- one of the main types of equipment at any woodworking enterprise, and their correct choice often determines not only the quality of the product, but also the productivity of the enterprise. This means that when choosing a machine, you should pay attention not only to its price, you also need to carefully study the design of such equipment and the offers of potential suppliers, in particular, comparing them with the needs of the enterprise, and only then make the final decision on purchase.
Andrey MOROZOV,
"Media Technologies" company,
commissioned by LesPromInform magazine
Product size quickly adjusted using special rulers by moving the right and upper spindles (the left and lower spindles are adjusted within a small range to compensate for tool wear)
Innings blanks occurs through a powerful gearbox using two pairs of upper and lower, grooved, spaced apart from each other. This solution makes it possible to increase the reliability and accuracy of feeding insufficient workpieces good quality and high humidity (unlike the rowan grouse located nearby).
Four-sided machine "START 5x210" complete with system of stepless feed speed adjustment, allowing you to optimally adapt to the available material for work.
Exact workpiece position in two planes is provided by special support plates running almost the entire length of the desktop and paired spring-loaded rollers. The pressing force of each roller is independently adjustable over a wide range. The paired design of the rollers allows the pressing force to be evenly distributed.
Precision grinding of working shafts four-sided machine "START 5x210" guarantee the complete absence of axial and radial runout of the tool.
High spindle speed(4500 rpm) allows you to achieve high quality finishing surface. Optionally, it is possible to install one or two upper spindles with a rotation speed of 6000 rpm.
Four-sided planing machine "START 5x210" equipped protection system from reverse ejection of the workpiece.
The bed is designed in such a way that it provides easy access to all important components of the machine, while having the necessary rigidity to eliminate vibration during operation.
Work surface The table is made of especially strong steel, which increases its service life, and is also additionally ground to minimize feed resistance and increase processing accuracy.
Working surface service life amounts to at least 10-15 years However, if necessary, this part can be replaced separately from the rest of the equipment. Replaceable work surface table makes the service life of the machine practically unlimited, unlike analogues, where the machine frame and its working surface form a single whole.
The electrical systems of the machine are controlled by an independent mobile console.
The machine can be equipped with a special reception table, with precise height adjustment. Correctly selected height of the receiving table will avoid “undercutting” at the end of the workpiece.
The compact dimensions and light weight of the machine make it quite mobile and easy to install.
The most simplified, but well-thought-out design ensures its high reliability.
Used for the production of various construction and finishing materials, as well as furniture. Many of your most important goals can be achieved with this reliable equipment. Setting up the tool is a feasible task for those who learn the basic principles from the presented article.
The central part of the machine is a cast planing table, which is mounted on a stable tripod. Thanks to this design, vibration is eliminated. The planing table also includes a bottom cutter and 2 side cutters. The upper cutter and rollers are fixed on a tripod. They move along massive rods. 4 cutters are powered by separate motors.
Machine setup steps
Preparation for work begins with adjusting the planing table. This prevents unwanted mechanical stress on the workpiece. Only correct installation of equipment guarantees high quality processing.
Table setup
The gap remaining between the part and the table should be no more than 0.127 mm in length. If the rear of the platform is mounted too low, the workpiece will begin to lift off the bed. For this reason, the edge will be processed with more curvature than required, and an incorrect cut will be formed.
In a configured machine, discrepancies at the joints of these parts are eliminated. Otherwise they will be noticeable.
When set correctly, the pressure bar creates pressure, which causes cutting to occur with some effort. If the pressure is not felt, the end of the workpiece will not be processed properly.
Feed Setting
In order for the feeding of any elements to be smooth, ensuring continuity of the work process, precise adjustment of the position of the lower rollers is necessary. They should be aligned with the top cutting head. The leading feeder should be located above the second one.
Placing both rollers at correct setting corresponds to a straight tangent to the comb part of the lower rollers. The conditional line is directed towards the cutting head.
At the same time, the intersection of the frame should be fixed only in front of the upper head.
Setup before working with short workpieces
Situations often arise when it is not possible to hold a tightly laid workpiece. In this case, feeding is used through an automatic feeder, which can work with any length. This principle is due to the fact that it is almost impossible to ensure the movement of the workpiece at the required speed manually.
If it takes 2-3 seconds to stop, the cutting edges of the rotating heads may instantly become dull.
The main indicators of any woodworking production are quality work and productivity. To fulfill these conditions, you must have the appropriate equipment. One such equipment is a four-sided woodworking machine.
Design and scope
Relatively recently, designs that combine several operations have appeared in the wood processing industry. Processing wooden products this happens on four sides at once. This equipment is most often used for milling and jointing.
The woodworking machine consists of:
- spindle section;
- part feed unit;
- equipment parameter control systems.
On one side there can be several processing heads, which reduces the cost of manufactured products and reduces the time for performing a certain operation.
The four-sided machine is designed to perform the following operations:
- Milling. Instead of planing shafts, disk cutters are installed on the working heads of the equipment, which makes it possible to do longitudinal milling. To carry out processing with finger cutters, it is necessary to periodically stop the parts, however, this is not provided for by the design;
- Planing and jointing. This can be done using shafts with blades of a certain configuration installed on them. The design of the machine makes it possible to simultaneously perform finishing and roughing;
- Reaming and profiling.
Most often, such models are used to create lumber with a flat surface or profile. All the work can be done in one pass.
Using four-sided machines you can make products such as:
Classification and differences of machines
All four-sided woodworking machines can be divided into:
- thicknesser planer;
- longitudinal milling.
Longitudinal milling machine used for cutting along the length of the material to the desired size. This woodworking equipment can perform profiling of any complexity. The lower shaft of the knife, taking into account the thickness of the wood being planed, moves together with the tabletop in the vertical direction.
Thicknesser used to plan a part to a specified thickness on both sides simultaneously. It is initially planing, but has additional function profiling. Such a device can produce shallow profiling with a simple locking design of a small beam.
Processing wood on four sides simultaneously helps save time, increasing production productivity. That is why four-sided machines are the optimal equipment in the construction and furniture sectors.
Main criteria for selection
Considering that a machine for complex woodworking is expensive equipment, when choosing it it is important to take into account technical specifications and all the nuances of the design. Equipment performance depends on:
- speeds and timber feeding systems;
- degree of processing and dimensions.
Choosing the optimal machine model, you should pay attention to:
In order to accurately position the workpieces relative to the machining center, a sensor system is required. In addition, when analyzing the model, you should take into account the cost of components, the degree of remoteness of the manufacturer’s service centers and warranty conditions.
Design of machine components
To understand the operating principle of the equipment, you need to consider design features machine, which includes many nodes.
Some equipment models include a joyter, a hydraulic spindle and a number of working tools. Such devices sharpen knives directly during product processing.
Purchase of a machine
Longitudinal milling machine can be purchased at specialized construction stores, but it is better to buy it directly from the manufacturer (if we are talking about domestic producers). You can rent equipment or purchase it in installments.
Before purchasing equipment, you need to pay attention to the following main points:
- performance;
- accuracy;
- reliability of operation;
- availability of service;
- equipment price.
If a four-sided wood saw will be an addition to an existing line, it is important to consider its dimensions. When purchasing, you must take into account the technical parameters and combination various options processing, weight of equipment and speed of work.
Some companies providing such equipment are still little known. Price for their products relatively low, but the quality is adequate. For example, the German brand Beaver. The cost of their products is low due to the fact that production is located in Taiwan and China. But parts of the assembly are made in Germany.
When choosing equipment, you should not consider cheap Chinese-made models. Please note that it will be very difficult to find spare parts for them.
Service
Any machine tends to break down over time and its component parts wear out. In order to have fewer interruptions in work for such reasons, it is advisable to choose the equipment that is most durable and wear-resistant.
In addition to productivity, it is important that the machine is as safe as possible. Therefore, the presence of limit switches, electric brakes and a metal protective casing with sound insulation is provided.
Processing of products on a machine must be as accurate and high quality as possible. For these purposes, it is important that the device has statistical and dynamic balancing of all fixations of parts.
When operating the equipment, you must adhere to the rules specified in the instructions for it. You cannot process workpieces that are larger in size than those provided for by the rules. It is imperative to carry out preventive and renovation work to keep the equipment in working order.
It is very important to install the machine correctly, taking into account not only its dimensions and weight, but also the size of the wooden blanks. The operator should not have to deal with any difficulties associated with feeding the material.
Pros and cons of equipment
One of the most positive qualities four-sided machines - high productivity. To achieve optimal results, the design must be equipped with a software numerical control unit. Then the influence of the human factor will be minimal.
The conditions for the correct preparation of the program must be met, and the workpiece being processed must be accurately measured. In its optimal configuration, the equipment is designed for processing cylindrical workpieces and rectangular beams. Jointing and milling of sheet materials can be performed on both sides. Features of the operation of machines of this type are the following factors:
The main disadvantages of woodworking four-sided machines are the high cost and complexity of setup. However, in production line conditions these indicators are not significant.
Maintenance of four-sided machines with manual feeding and sorting of material, as well as acceptance of processed parts, is a labor-intensive process with low labor productivity. To eliminate certain difficulties for four-sided machines, a conveyor line has been developed that automatically feeds and receives workpieces.
Two mechanized blocks are installed on the sides of the operating machine - feeding and receiving. In total, the service line consists of four modules, which ensure not only the uninterrupted supply of workpieces, but also the possibility of their defect detection due to the formation of buffers caused by the lower speed of the conveyor. A longitudinal conveyor with a dumper and a transverse conveyor with a device for feeding workpieces for four-sided machines is located on one side, and receiver and a sorting conveyor ensure that processed materials are received from the other side of the machine. The main application of the feeding and receiving system was found in large-scale enterprises and in workshops for the production of molded and joinery products, as well as laminated veneer lumber and panels. Ideal for processing large molded parts.
Blank supply lines for four-sided machines
The construction of automated production lines for the production of furniture or standard house construction requires mechanization of the supply and reception of materials for four-sided machines. Experienced specialists of our company will help you not only purchase this conveyor equipment, but also find it right place in a woodworking shop.
Loading...
