SU1371787A1 - Apparatus for monitoring the process of cutting - Google Patents

Abstract

The invention relates to metal working on machine tools and is intended to measure the wear of a cutting tool and also to control the cutting process. The purpose of the invention is the innovation of precision due to the increase in the noise immunity of the device. To do this, a vibration sensor 7 is installed in the device on the cutter, a sensor I of the angle is installed on the shaft of the machine. of the second position of the N1pindle, which is connected to the third input of the counter 4 impchls through serially connected (jiojiMnporer 2 time intervals and block 3, the allocation of even and} 1 interval). To the first input of the counter 4 im H. H () DC.1K) A generator (i pulses) is connected via block 8 to the second input of block 8; a vibration sensor 7 is connected. The output of the pulse counter is connected to the input of register 5. The output of the generator 2 time intervals is connected through the switching block 9 to the second input of the counter 4 pulses and the second the input of the register 5. During the cutting process, the sensor 7 recognizes the wheel} 1i of the cutter and the signal of DROUT oscillations goes to the second input of the block 8 (L

Description

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fall. The first input of block 8 receives a signal from the generator 6 of pulses, which, however, is at the output of block 8, only if there is a signal from sensor 7. Thus, a false operation of the device is prevented. The signal from sensor 1, which represents pulses with a frequency proportional to the frequency of rotation of the machine spindle, arrives at the input of the imager 2 time intervals. The block of formation of time intervals restores them to a rectangular shape, and from its output these pulses are fed to the input of block 3. From the output of block 3, the signals are i and either high or low, the duration of which depends on the frequency of the pulses b. Yuka 2 time interval formations are fed to the reversing input of counter 4. The high level of the signal of block 3 corresponds to an even interval between pulses, to a low level odd 1

The invention relates to the field of metalworking and is intended to control the cutting process, as well as to determine the size of wear of the cutting tool.

The purpose of the invention is to improve the accuracy due to the new noise immunity of the device.

FIG. 1 shows a diagram of a device controlling the cutting process; in fig. 2 - time diagrams; in fig. 3 - dependence of tool wear.

The VcTpoik TBo monitoring of the cutting process contains the sequentially connected sensor 1 of the angular position of the pindel, shaper 2 time intervals, block 3 B1) | division of even and odd intervals, counter 4 pulses and register 5, generator 6 pulses and vibration sensor 7 through the first and second inputs the coincidence unit 8 is respectively connected to the first input of the pulse counter 4, the time interval former is connected via the switching unit 9 to the second input of the pulse counter 4 and the second input of the register 5.

The control device for the cutting process works as follows.

When spindle arises, angular sensor when the spindle rotates with it, pulses appear at its output with a frequency proportional to the speed of rotation of the spindle (timing diagrams in Fig. 2). By arriving at block 2 of forming time intervals, these pulses are restored to the rectangular interval. The counting input of the counter 4 receives the signals of the generator 6 in the form of pulses of a fixed frequency, they are summed up if the reverse input of the counter 4 has a high level signal, and is subtracted if the signal is low. Thus, the length of the even and odd interval is constantly compared. between inter; 1y and m pulses from sensor 1, the result of the comparison is recorded in regisGr 5. Switching unit 9 controls the operation of counter 4 and register 5. The switching unit is clocked by the signals of unit 2. The frequency of impulses of sensor 1 depends on the moment ) Suddenly, if the mo- ment increases, the frequency decreases, s, which means the length of the even interval between pulses is not equal to the length of the fuzzy interval. Consequently, by the result of their comparison, it is possible to judge about the change in the moment of cutting, and, therefore, about the wear of the tool (cutter). 3 il.

at the output of the even impulse and odd intervals at its output, at 1, a high level signal, at the arrival of the second imp signal of a low level, at the third impulse signal high, etc. The duration of the signals is not 1) iodine pulses, received from the driver 2 in) the interval. Unit 3, vyde,; 1enp even and irregular intervals connected to the reversing input of the counter 4 impulses.

Until the cutter touches, ui- | There is no signal at the output of the sensor 7, therefore, the rectangular pulses from the generator 6 impulses do not pass through the block 8 coincidence, working 11 as the trays I.

When the cutter touches the workpiece but the vibration of the cutter and the workpiece is n vibration sensor 7, installed on the cutter body, begins to accept the vibration, a high level signal appears on its Biiixo, so the coincidence block 8 starts to pass impulses of the generator 6 impulses and post on the counting input of the counter 4 pulses. If it reverses its high-level input signal, then the pulses of the generator 6 are added up, and the EU; | and the signal is of the low | -o level, then the pulses are subtracted. In this way, the number and impulses of the generator 6 pulses transmitted to the counter 4 pulses during the period of the even and odd intervals are compared, the result of the comparison is written to the register 5. The writing to the register 5, resetting the counter 4 pulses and reading from it are controlled by the switching unit 9, which is clocked by the shaper 2 time slots. Let us turn to the time dependence of the tool (Fig. 3): section 1 - burn-in area, work section 2, section 3 - subcritical wear area. When the cutter is machined, the cutting time quickly increases, therefore, the frequency of one zero zero from the angular position sensor 1 of the pshiped 1 decreases, since the pinch slows down, which means that the number of pulses passed by the counter 4 pulses per second the period of the even and odd intervals is different, and the difference characterizes the wear at a given time, as well as at the time of cutting. In the working area, the moment increases more slowly and the difference in pulses is smaller, in the area of wear this difference is very high, as the moment of cutting increases rapidly. Thus, it is possible to determine without any time the moment of running-in and wear of the tool. It is also possible to estimate the absolute change in the moment of cutting from the beginning of the treatment, if we integrate the difference imffj7O / (

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nulls of even and odd intervals at each time point that can be used in monitoring and controlling the cutting process.

Claims (1)

Invention Formula The control device for the cutting process, which contains an angular position sensor, connected in series a pulse generator and a coincidence unit, a switching unit whose outputs are connected to a pulse counter and a register, whose input is also connected to the output of a pulse counter, in order to increase accuracy, a vibration sensor connected to the input of the coincidence unit was inserted into the device, and sequentially, a time interval generator and an even and odd interval allocation unit were connected 1e, and the course of the time interval generator is connected with the output of the angular positioning sensor Schnindel, and the output also with the output of the switching unit, the input of the output box of the penny even1) and odd interval.pov is connected to the output of the coincidence unit, and B |) | . Tips. five and 2 Fig.Z t