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Classification and types of mechanisms

All manufactured devices are divided into several categories:

• manual;
• locksmiths;
• machine tools;
• pneumatic.

Machine vices are additionally subdivided into turning, milling and drilling vices, depending on the type of machine they are designed for. The devices are attached to the frame by means of dowels, screws and a wide range of additional elements: magnets, levers, eccentrics. They can also have removable jaws of different sizes and shapes for attaching various workpieces.

More often in the industry, steel, rather than cast iron, rotary machine vices with a mechanized (hydraulic or pneumatic) drive are used, which accelerates the fastening process of the part and increases the reliability of fixation.

Types and purpose

Products are divided into several types, depending on the type of operation they were designed for:

• fixed;
• swivel;
• precision;
• universal;
• modular.

The most convenient rotary devices are those that allow you to change the angle of processing of a part directly in the process of work (without the need to fix it in a new position). This is made possible by a movable platform that is driven by a drive. However, high mobility negatively affects the fixing strength, so it must be compensated for by other parameters (for example, a decrease in the number of revolutions).

If increased accuracy is required, precision machine vices are used, which can also be:

• rotary (the workpiece is attached perpendicular to the tool);
• biaxial (two mounting options are supported);
• sinus (fixation at an arbitrary angle).

They are equipped with heavy-duty jaws with additional grinding, which improves the adhesion between the workpiece and the workpiece, and are used for milling work.

Choosing the right equipment

The right choice of pivoting machine vice can achieve the following benefits:

to increase the fastening strength, which is especially important when working with large metal workpieces;
reduce the cost of maintaining the production line: a high-quality device is insensitive to mechanical damage, corrosion, well resists wear;
to increase the accuracy of work without changing the technological cycle;
to achieve rigid fixation without backlash, which reduces the risk of marriage.

When selecting a rotary machine vice (for example, a globe vice), first of all, their sizes are taken into account: 80, 100, 125, 160, 200, 250, 320 mm. It should be remembered that the numbers can mean different parameters: for example, the marking "100 mm" indicates the width of the jaws, and the mark "200 mm" can show their maximum solution.

It is also necessary to rely on the type of equipment (milling, grinding or other) for which the vice is purchased, and take into account the features of the workpieces (size, shape, weight, material). This will determine the preferred body and jaw material (steel or cast iron), suitable models, and the required accuracy class.

If the machine vice is purchased for the first time, then it is better to get professional advice from the manufacturer beforehand - this will avoid mistakes when buying.

The most important technical characteristics of the vice

When choosing a specific device, you must carefully read its technical parameters and capabilities. First of all, in order not to throw money down the drain, it is necessary to find out which machine equipment they are intended for installation on (milling, surface grinding, planing, broaching, drilling or other machines).

Then it is necessary to check whether the width of the working jaws is sufficient, or whether they are too narrow and will press with great effort on the surface of the workpiece, leaving dents in it.

The clamping force is also important. The stroke length allows you to determine the maximum possible linear dimensions of the workpiece installed in the vice

In the event that a vice is purchased for a small hobby machine installed in a garage or in the basement of an apartment building, or even on a balcony (there is also such a thing!), Then, of course, their mass is a critical parameter. The limit on the weight of a product installed on a small hobby machine cannot be exceeded, since the mechanical components of such a machine will quickly fail.

Appointment

The movement in machines equipped with a rotary device is carried out by the tools, not the part. This principle helps to reduce the cost of the slewing gear. However, it is theoretically possible to do the work from the back of the part from the master. In practice, it is unlikely to be done, the visibility of the workpiece by the master when performing the work is almost absent.

The following situation is a good example. It is necessary to process a metal part, the shape of which is a bar. On each side, a recess must be made, the shape of which is a half-cylinder. The master does not see the cutter and does not know whether it reaches the end of processing - the height of the workpiece does not allow this. The parts can be corrected if the cutter has not completed its work to the end. But there are difficult recesses in which this will not be possible.

When using a rotary machine vice 160-250 mm, the situation is different. The foreman will have to stop the work to walk around the machine, in order to continue it later. The cutter must be retracted beforehand.

Machine milling vices are used when working on devices where machine control is carried out for a number of reasons.

1. The machine can be programmed so that the workpiece to be machined turns from the side where it can be seen. The master will be able to control the processing process. This will be useful to him especially when putting a new program into operation. The error can be seen immediately, and not after the manufacture of the part.
2. There are situations in which it is necessary to turn the workpiece and the cutter must remain in place. It could be making a perfect circle.
3. A large number of workpieces are convenient for processing when fixing in a machine vice rotated by 90 °. Then the working position is set.

Design and principle of operation of the rotary vise

The tool is made of ductile iron or stainless steel. All functional edges are hardened and ground for added strength.

The design of any vice contains: a base, a pair of clamping jaws, one of which is rigidly fixed, the second is movable, a guide and a clamping screw. In addition to the basic elements, the swivel ones are equipped with additional parts that expand their functionality.

The base is a bar on which the clamps, screw and all gears are attached. Jaws (scientifically clamps) are located on bearings, one of them is attached to a clamping screw. In homemade designs, you can use a simple threaded rod. The factory modification implies the placement of the transmission gears on the screw. The system for driving the jaws can be different. The simplest one is that the screw rotates in the thread of the body and pushes the clamp with its end. That is, when the screw is twisted to the right, the jaws come closer, when rotated to the left, they move away.

In rotary models, the mechanism for moving the clamps is usually much more perfect and contains transmission gears. Gears can be tapered or rectangular.

Clamping strips

One of the features of the device is the presence of clamping bars. The bar grips the part and then locks onto the base. Planks are made of various shapes: crosses, flat plates, squares, horseshoes.

On the most advanced pivoting vices, the strips are equipped with spring devices that allow for the most convenient processing of the workpiece.

The peculiarity of the rotary design is that a conventional vise is installed on a rotary table that can move straight and in a circle. Thanks to this, the part can do it yourself to the corners from -10 to +90 degrees, rotate 360 ​​degrees in the plane and fix in any required position. Many models have a removable base.

Rigidity is the second essential requirement for a machine vice. They are installed on the machine using a key type and are firmly fixed with bolts.

Main technical characteristics:

• dimensions of the sponges (width, height, divorce);
• height and length;
• clamping force;
• longitudinal and transverse movement;
• weight.

The dimensions depend on the dimensions of the parts that can be reliably held. The clamping force for hand-operated tools ranges from 20,000 to 55,000 N. The minimum weight of the device is 7 kg, the largest models weigh over a ton.

Carpentry

The Moxon Joiner's Vise is designed for itinerant joiners and carpenters. In Europe, the USA and Canada, this is a rather demanded specialty: at the local prices for sawn timber, many customers require that the master work with them on site and leave the smallest trimmings, up to sawdust and shavings, to the owner. A pair of Moxon vices, which makes it possible to work with long materials, can be carried in the trunk of a car, on a bicycle, a scooter and carried in a bag. The find was immediately appreciated by amateurs - Moxon's vice allows you to quickly and reversibly turn any more or less durable table into a carpenter's workbench.

The appearance and method of fastening the Moxon mobile carpentry vise are shown on the left and in the center in Fig. On the right - the device of their amateur version for fastening to the table tightly.

Appearance, fastening in working position and the device of the Moxon carpentry vice

Moxon's grip gave rise to many modifications. Drawings of one of them, a very simple and convenient carpentry vice of only 3 boards and a pair of clamps, are shown in Fig. Further. True, in fact, you will need 2 more short clamps to attach the vice to the table. Extra 4 clamps (also not a very cheap pleasure in our time) may be expensive for an amateur. But for the carpenter - individual entrepreneur working on call, such a vice is a godsend, they can be disassembled and carried with you in an ordinary duffel bag.

Drawings of homemade simple joinery vice

Design and function of clamping devices

Since the machine vise is necessary to securely hold the workpiece in place during machining, it consists of strong steel elements. Depending on the type and purpose of the machine vice, their design can vary greatly.

The mid-range model includes rotary models, the functionality of which allows you to perform drilling operations more efficiently. The advantages of the first and second types are combined in universal attachments for a drilling machine, which, naturally, makes the cost of such devices quite high.

Even a vice of the same type, but produced by different companies, may have certain design differences. This is due to the fact that each of the manufacturers is trying to endow their products with additional options, to make them more reliable and convenient in operation.

Professional machine vices can be equipped with various clamping bars

Whatever functionality the machine vise has, the basis of their design is made up of mandatory elements, which include:

• strips that act as the base of the vise;
• two jaws providing clamping of the workpiece to be processed;
• a screw with a handle, due to which the movement of the movable clamping jaw is ensured;
• plates serving as working elements of the clamping jaws;
• a number of additional details.

The device of the simplest machine vice

The bar, which serves as a base, is a supporting element on which all other parts of the vice are fixed. It is on the strip, which is made of hard and wear-resistant metal, that a hole for a screw is drilled, and movable and fixed jaws are mounted. To ensure the accuracy of movement, the lower part of the movable jaw has a rectangular shank that is inserted into a cutout made on the fixed jaw.

The shank responsible for the parallel movement of the jaws

The screw responsible for the movement of the movable jaw is in connection with it, which is provided by a special retaining ring. Rotating in the threaded hole of the base bar, the screw moves the movable jaw, thereby providing clamping of the workpiece being processed on the drilling machine. To understand how the vice works, you can watch the corresponding video.

Both serial models and home-made vise for drilling The machine tool can be made according to various schemes of the effect of the screw on the movable jaw. In the simplest vise models, which are easy to make with your own hands, the screw directly connected to a movable jaw, which he either pulls (unclenches the jaws) or pushes (squeezes the jaws), depending on the direction of his rotation. In more complex models, which can include both fixed and rotary vices, the rotation of the screw is transmitted by gears, which facilitates the work of the drilling machine operator. Thanks to the gears, very little force is required to compress or unclench the vise jaws.

It should be borne in mind that the presence of a gear mechanism is not at all a criterion that should be emphasized when choosing clamping devices for a drilling machine. Many well-known manufacturers, whose products are popular with specialists all over the world, produce devices whose principle of operation is implemented according to a standard scheme, which does not make them less effective or inconvenient to use.

Hydraulically reinforced vise provides stable compression independent of shock and vibration

Pressure plates, or strips, are important structural elements of any type of vice that undergo significant loads during operation and ensure reliable fixation of the workpiece being processed. These elements, made of durable metal, are attached to the working surfaces of the clamping jaws using screw connections.

In the standard version, the clamping strips have a flat working surface, on which a cross cut is applied. More specialized types of strips are also used, which are necessary for processing workpieces of a certain shape. The working surfaces of such strips can be made in various shapes (angular, concave, etc.). In some modern vise models, the clamping bars may be spring-loaded. This design makes it possible to slightly increase the convenience of fixing the parts in the clamping device of the drilling machine.

Vise with prismatic jaws

The use of special tools for processing parts

When processing parts, it is required to perform various types of work using machines of various types, on which machine fasteners are installed:

• machining centers (turning, milling work);
• milling machines (milling work);
• surface grinding machines;
• drilling machines;
• electroerosive machines;
• CNC machines (milling, turning).

According to the degree of adjusting clamping force when fixing the workpiece, fasteners can be classified:

• using a hydraulic booster mechanism;
• using a pneumatic drive;
• using a screw drive.

Fixing devices machine tool (pneumatic) equipped with a hydraulic drive are used when carrying out work when it is required to fasten the workpiece with the application of great effort.In some types of devices, the hydraulic cylinder used makes it possible to partially compensate for the vibration that occurs during the cutting operation.

The use of various drives makes it possible to achieve high precision in parts processing and automation of the product manufacturing process.

The use of a machine vise allows:

• create an increased degree of fixation of the workpiece during processing;
• ensure high reliability of parts processing;
• to carry out long-term operation of equipment while maintaining quality indicators.

The use of various types of machine vice allows you to perform a wide range of different operations related to the processing of parts.

Installation and storage

Machine milling vise is most often installed directly on the machine, or more precisely, under the cutter. They will work together with the machine, so there should be no options in how to install them. Most of the machines already have fastenings for a vice, and the instructions for such units contain recommendations and requirements for them. However, you can always use a manual device or a vise without software control, which is set at the required height so that it is convenient to work with objects of different sizes.

lubricate the working surface of the machine

There are many rumors on the Internet that any hydraulic device should never be turned over and should be handled with extreme caution. In the case of a vice, this is not entirely true.

Due to the fact that a closed-loop system is used in the hydraulic vice that does not support draining or refilling of liquid and is absolutely sealed, such a device can be turned as desired. Its only weak point is considered to be the pipes used for the liquid. If they are located outside of its body, then it is best to take care that they do not fray and do not break, because in the event of a fluid leak, very expensive and extensive repairs will have to be done. Especially if the liquid was not water.

Thus, a machine milling rotary vise is necessary to fix the workpiece on the working surface of the machine in such a position that it can be conveniently processed. Such a device provides a fairly high and accurate clamping force on the workpiece. There are several types of rotary vices that have their own advantages and disadvantages.