The automatic tool change of the spindle of a vertical machining center and a CNC milling machine is an indispensable function in machine tool processing.
When the machine tool is changing the tool, the tool on the spindle can be removed only after the tool is released. After the spindle is replaced with a new tool, the tool can be broached and the tool on the spindle can be tightened. Up.
Usually the structure is through the action of the loosening cylinder to push the pull rod with the disc spring to loosen the chuck of the machine tool holding the tool, and then the robot or manual tool change action, after the new tool is replaced on the spindle, The loosening cylinder moves in reverse, the piston retreats, and the pull rod retreats under the action of the disc spring to tighten the cutter.
During the machining process, when the tool needs to be changed, under the action of high pressure oil or compressed gas, the piston rod of the tool release cylinder gradually contacts the upper end of the spindle tie rod under the action of high pressure oil or compressed gas, and the contact surface between the tool release cylinder and the tie rod is generated_ The force is increased accordingly.
When the force exceeds the pre-pressure of the compression spring, the tool release cylinder and the floating ring move upward together until the floating ring and the fixed ring contact each other. After that, the force between the tool release cylinder and the tie rod is determined by the floating ring and the spindle The rigid body formed by the member bears it.
Using the spindle bearing tool loosening and unloading device, the spindle bearing can be free from the influence of large axial tool loosening force during the frequent tool change process, improve the bearing life, and maintain the stability of the spindle bearing accuracy. The stability of tool clamping during torque cutting.
In order to improve the stability and service life of the machine tool spindle bearing accuracy, it is necessary to adopt the spindle bearing loose tool unloading structure.
