The overall automatic balancing system developed on the cutting machine was successfully developed

With the increasing popularity of high-speed machining, the balance of tooling has become a critical issue. It is related to the efficiency of machining, the safety of operation, and the life of the machine tool spindle.

The commonly used tool balancing methods are: avoiding unbalance from the structural design; using the method of drilling (milling) on ​​the handle; adding a counterweight; setting the radial adjustable balance screw; Adjust the balance ring to balance the tool.

A common problem with all of these methods is that they must be used in conjunction with a balancing instrument. This increases the cost of equipment purchases and requires a considerable amount of equilibration time; and the object of balancing is limited to the components of the tool and the tool holder, without consideration. The unbalance of the spindle of the machine tool and the imbalance caused by the misalignment of the installation when the tool is loaded into the spindle of the machine.

In order to overcome the problems existing in the above balance method, it is necessary to propose a new concept of balance and develop a new balance method. For this purpose, Kennametal Hertel introduced an overall automatic balancing system that uses electromagnetic technology to automatically balance the cutting tool with the machine tool spindle as a whole (this is called the overall automatic balancing system TABS-TotalAutomatic BalancingSystem. It enables the tool to be loaded into the spindle of the machine tool. , Automatic balance with the spindle on the machine tool. When balancing, the tool rotates with the spindle at the working speed, and the entire balancing process does not exceed 2 seconds. This on-machine balancing method realizes the whole consisting of the tool, the tool holder, and the machine tool spindle. The balance of the rotating system.

This balancing method can balance the entire rotating system as long as the kennametal/Baadyne electromagnetic balancing system is configured on the existing machine tool and Kennametal Hertel's electromagnetic balance toolholder is used.

The principle and composition of the system

When working, two sensors measuring vibration are mounted on the housing of the spindle of the machine tool and measure the vibration of the spindle of the machine tool on two planes. The controller processes the vibration sensor from the spindle housing and the signal from the position of the balance ring on the shank. With these three signals, the controller can measure the spindle speed, phase angle and position of the balance ring and display their values. .

In order to reduce vibration, the controller first performs an auto-balancing procedure: using an allowed rating to compare the vibration values ​​measured from the spindle of the machine, then the controller sends a pulse signal to transmit energy to help balance the rotor (balance ring) ) Turn to the position calculated by the controller; finally through repeated measurements, comparisons and adjustments, gradually approach and eventually achieve the allowable rating.

The rotating balance ring on the shank is the rotor of the two counterweights. Changing the relative position of the two can correct the entire imbalance. In the normal state, the two rotors are held by a permanent magnet at a certain position, and even if a very large rotational speed change or violent vibration does not change their positions, the position of the two rotors is changed only under a corresponding program instruction.

In this system there is also an adjustment frame with a coil ring corresponding to the position of the balance ring of the shank, which corresponds to the stator. When used, it is mounted on the machine table, within reach of the spindle travel of the machine, but does not interfere with the machining process and tool change.