Creating any object, it is necessary to adhere to accuracy, and hence the fixation. Modern milling machines perform their work with tolerances of tenths of a millimeter, while the workpiece, that are in them, do not stand still, and move in two planes. At the same time the person can not operate the machine, because the unit can be pre-programmed to perform certain actions.
Hence the need for a universal clamp, which allows you to work quite quickly on the machine. In the last century, rotary vices were developed, which have undergone small changes to date, are actively used as in small workshops, and in the shops of large enterprises.
Purpose of machine rotary vices
In most machines with rotary devices, the tool performs the movement, not a blank, which, in theory, should significantly save on the rotary mechanism. However, work with the tool on the workpiece side, reverse wizard, in theory it is possible, but in practice it is absolutely impossible to do, since the master does not see literally, what is he doing.
The following situation should be presented as an example. A metal part in the form of a bar is taken. The master must make a notch in the form of a half-cylinder on each side. The height of the bar does not allow him to see, whether the cutter on the other side of the part reaches its end. Of course, everything can then be corrected, but what to do, if it is necessary to make a much more complex notch instead of a half-cylinder.
In this case, there are only two ways out - to stop work and completely bypass the machine to continue it, or in advance, taking away in the direction of the cutter, use swivel vices, allowing you to quickly return the workpiece to the master of the desired side. The difference between the two situations is about a minute, therefore rotary vices increase productivity of the master by about a quarter.
There are several reasons for using machine milling machines on machine-controlled units:
- The machine can be programmed as follows, to always turn the workpiece with the side open for inspection. This allows you to control the work process, which is useful when testing new programs, since in this case you can detect the error immediately, and not at the end.
- Sometimes it is necessary to leave the cutter in place and turn the part itself, example, when you need to perform a perfect circle.
- Many parts are very convenient to install in machine vices, which are returned on 90 degrees. After that, the vise is simply placed in the working position.
Application of milling machine vices
Rotary devices cannot be used on their own, but only in combination with a milling machine. In such units, the vise is used for this purpose, to very securely fix the workpiece under the part and allow the milling machine to process it. This machine milling device is used mainly:
- in small workshops;
- in the shops of large factories.
Milling rotary devices are used in small workshops for the manufacture of furniture fittings, and for working with small metal objects, example, keys of complex configuration. They are also used when working with plastic windows, when you need to adjust them.
In large factory shops milling vices are used in the manufacture of aircraft turbines, parts of engines and other mechanisms, whose design has a complex shape.
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Machine rotary vices can be:
- manual;
- pneumatic;
- hydraulic.
It is necessary to disassemble each species in more detail.
Manual milling rotary vices
At the heart of such machine milling vices lies a rotary disk, allowing the software or machine operator to rotate them on 360 degrees together with the subject, which is clamped in them. The disk is fixed by means of a dense clip, which is a metal rod with a thread and a static regulator, taken out for the turning part. exept this, in the most rotary disk for stronger fixing make deepenings.
Ordinary hand vises are bolted to the rotary disk. They consist of two parallel metal plates, in which the inner surface is covered with a damping material.
The adjusting design is a perpendicular threaded rod, which is welded to the central part of the outer side of the plate. The other end of the rod has a handle, and he himself is stretched through a tightly fixed regulator, in which the inner surface also has a thread. The length of the rod is calculated as follows, so that the distance between the plates of the vise was about one millimeter, even with the rod fully unscrewed. As a result, you can use the knob to set the desired distance between the plates, as well as adjust the clamping force of the workpiece, without fear of damaging the vise.
There are many modifications of this design. Example, on one vise both plates can move at once due to existence of rather difficult mechanism, and on others there is a lever instead of the handle and the transfer mechanism, which greatly facilitates the work of the employee.
Manual machine milling device is most often used in small workshops, as well as for work with fragile objects, which automation should not be trusted. Such a machine tool has a low cost, it is very practical and quite easy to use.
Pneumatic milling rotary vices
This design is also based on a rotating disk, to which the vices are attached, consisting of a rail and two plates.
The control design of the pneumatic milling machine is a sealed tube, in which one end joins the central part of the outer side of the movable plate, and the second - to the electric or manual pump. If there is a need to increase the force of the clamp, into the tube, by means of the pump, pump a large amount of air, which begins to expand, as a result, the plate begins to move forward. If you need to reduce effort, begin to bleed air from this tube and inject it into the second tube, which connects the drive plate to another pump and performs the opposite function.
If the vise will be used in conjunction with an automatic machine, then instead of a clamp and a clamp from a rod miniature pneumatic vices will be applied, and in the basis of a disk the electric drive is often built in. This design allows the software of the machine to control the movement of the cutter and the rotation of the workpiece, which makes the work more efficient.
Pneumatic machine rotary vices promote the development of greater effort, than manual, however, a hydraulic design appeared on the market, which is the most effective.
Hydraulic milling rotary vices
By their design and principle of operation, they are fully consistent with the pneumatic, only liquid is used instead of compressed air. It's mostly water, however, a more elastic and viscous fluid is often used to develop more effort. in addition, pumps of hydraulic machines are connected to the tank with the necessary liquid, and do not remain open for air intake. Hydraulic machine vices are very popular in various industries. These compact devices are also used in workshops.
Competitors of machine rotary vices
The only competitor to this device is a non-rotating vise, which are based on its name, do not have such an extremely important function. However, such a device, without a rotary mechanism, is much cheaper, so when you buy them you can save up to 10% from the cost of hand vices or to 35% from the cost of hydraulics.
There is also little competition between manual and hydraulic devices. It is necessary to decide here, which will be better - significant savings or the opportunity to abandon it altogether, to adjust the vise by hand.
Installation and storage
Machine milling vices are often installed directly on the machine, and to be more precise, under the cutter. They will work together with the machine, therefore, there should be no options in the ways of their installation. Most machines already have clamp mounts, and instructions for such units contain recommendations and requirements for them. However, you can always use a hand-held device or vise without software control, which are installed at the required height, to make it convenient to work with objects, having different sizes.
Many are concerned about the issue, how to store the vise - together with the machine or separately? In the first case it will be necessary to grease well a working surface of the machine and to cover it with a tarpaulin or fabric. If miniature vices will be stored separately from the machine, then they should also be greased and wrapped in greaseproof paper. If the machine tool is large, then it is necessary to come with it in the same way, as with the machine itself.
There are many rumors about it on the Internet, that any hydraulic devices should never be turned over and handled with extreme care.. In the case of vices, this is not entirely true. Thanks to that, that a closed system is used in hydraulic vices, which does not support draining or topping up the liquid and is completely airtight, then such a device can be rotated as desired. His only weak point is the tube, used for liquids. If they are located outside its housing, it is best to take care of it, so that they do not wear out and break, because in case of fluid leakage must be very expensive and major repairs. Especially if the liquid was not water.
So, machine milling rotary vices are necessary for fixing the workpiece on the working surface of the machine in this position, so that it can be conveniently processed. This device provides a fairly high and accurate clamping force of the workpiece. Swivel vices come in several types, which have their advantages and disadvantages.