SU793721A1 - Method of monitoring cutting process at lathe operation - Google Patents

Description

one

The invention relates to metalworking on lathes and is intended to determine the state of the AIDS system, as well as to control and control the cutting process.

There is a method of controlling the cutting process during turning, in which the process is recorded by sensors located in the tool body, the amplitudes of the forces acting on which the process I. is monitored.

However, this method has no control over the state of the tool. cutting process.

The purpose of the invention is to improve the accuracy of controlling the vibration resistance of the cutting process.

The goal is achieved by the fact that the sensors use the method to set each other perpendicularly to each other in three planes, two of which are perpendicular to the axis of rotation of the part, measure the phase shift between the amplitudes of the two forces relative to the third one chosen as the reference, determine the difference between By these measurements and by the magnitude of the phase difference, the cutting process is judged.

FIG. Figure 1 shows schematically a cutter and a part during the cutting process; FIG. 2 - temporary agrams action comprised cutting forces.

The workpiece 1 during the cutting process affects the cutter 2 in the form of forces P, P, Pj which are mutually perpendicular. With respect to the axis 3 of the deggypie axis, sensors 4, 5, b are measured for measuring forces, and each sensor perceives the action of only that force, perpendicular to which it is mounted.

Accelerometers or other sensors can be used as a sensor to measure the internal stresses generated in the tool by the action of forces P, P, P

In the diagram of the action of the component cutting forces along the abscis axis, the current time is indicated. The ordinate axis is the action of forces, as well as the number of the sensor that perceives this action. The numbers on the abscis axis denote the moments of cleavage.

Claims (2)

Consider the action of forces in the cutting process. Starting at some point in time, which corresponds to the starting point of reference. The workpiece, having made a rotational motion, acts on the cutter in the strength of the forces 2. X action of force P, the bend deflects until the elastic force of the tool deformation exceeds the force P. As soon as the elastic force reaches its maximum, an avalanche-like process of chipping the workpiece material begins. The cutting part of the cutter under the action of elastic force makes a return movement, while due to the fact that part of the material of the shear layer is separated by D1 tangentially to the circumference of the workpiece, and the cutting speed is much less than the cleavage speed, then the force P2. decreases. The reduction occurs until the surface of the workpiece again touches the cutting edge. After touching, the process is repeated. The force Ru at the initial moment has a maximum value, since the contact area of the cutter on the rear face with the part has a maximum value. As the cutter sags, the contact area decreases, which leads to a decrease in the force Ru. The reduction of the force occurs before the beginning of the cleaved moment, as the tool returns to its original state, the force increases. The force P is due to the feed rate when the workpiece is cut. At the first moment of time, the force P has a maximum value, since the cutting edge has penetrated into the body of the workpiece. The next moment, under the action of SILYR, the incisor bends, and this is equivalent to the fact that the cutting part returns to the point preceding the initial moment (only regarding the effect of force P). In addition, the bending of the cutter is equivalent to the fact that at some point the feed is missing or equal to 0. Accordingly, the force at this moment will have a minimum value. The reduction of the force Py is caused by the fact that the cutting part of the cutter is displaced downward relative to the axis of rotation of the workpiece, therefore the contact area of the cut layer in the direction of the action of the force Py decreases. At the moment of chipping, the cutter returns to the initial state. The JB cutting process detects the action of the cutting forces, and since the cutter oscillates as a result of the action of these forces, the output signal of the sensors, which characterizes the action of the forces, is oscillatory in the limit, which can be taken as harmonic oscillation. Moreover, the action of forces in three planes at the same moment of time is unequal, which is explained by the delay in the action of forces in one plane relative to the other. Measuring this time lag, which is expressed in the phase difference between the amplitudes of the forces acting, judges the trajectory of the cutting part of the tool. If this trajectory deviates from a given judgment about the state of the instrument and the AIDS system. Claims method of controlling the cutting process during turning, in which the process is recorded by sensors located in the tool body, the amplitudes of the acting forces, which control the process itself, characterized in that, in order to improve the control accuracy of the cutting vibration, the sensors set the perpendicular each other in three planes, two of which are perpendicular to the axis of rotation of the part, measure the phase shift between the amplitudes of the two forces with respect to the third, chosen as From the reference, the difference between these measurements is determined and the cutting process is judged by the magnitude of the phase difference. Sources of information taken into account in the examination 1. USSR author's certificate I 416165, cl. B 23 B 1/00, 1974.