SU1763890A1 - Method and device for cutting tool edge condition testing - Google Patents

Abstract

The invention relates to a control and measuring technique. The purpose of the invention is to improve accuracy. The method consists in converting an optical signal reflected by the moving edge of the cutting tool into an electrical signal measuring the amplitude and duration of the electrical signal, and. determining the state of the edge from the measured amplitude and duration. 2 sec. and 1 z. p. f-ly, 2 ill.

Description

The invention relates to a control and measuring technique.

A known method for determining tool wear, by which the cutting emf value is measured, determines the ratio of the current cut emf value to the maximum transient emf value and determines the wear value using the specified ratio. This method is implemented by a device including an amplifier, analog-to-digital converter, threshold the device, the device for determining the maximum value of the EMF of the transition process, the memory device, the time master and the arithmetic unit oystva is not high precision control state of the cutting tool edge.

The closest to the technical essence of the present invention is the method of contactless measurement of the dimensions of parts selected as a prototype, in which the measured part is moved along the bearing surface, the optical radiation signal from the source through the translucent mirror and the lens direct From this surface, an optical signal is collimated by a lens and directed by a translucent mirror to another translucent mirror, which passes through a part of ovogo flow strikes the beam splitter and the other portion of the stream strikes the collimator and further - to semitransparent mirror, reflected from the portion of the flow which passes through the aperture and acts on the photodetectors, respectively. the signals generated by the photodetectors are directed to the inputs of the comparator, which provides the enable signal to the electronic key.

A device that implements this method includes a channel for changing the angle of rotation of the test surface, consisting of a translucent mirror, a beam-splitting prism, photodetectors, a compass

with

2

SL 00 O O

Rotor, as well as an electronic key. The disadvantage of this method is the low accuracy of control of the state of the edge of the cutting tool.

The aim of the invention is to improve the accuracy of monitoring the state of the edge of the cutting tool. The goal is achieved by applying the method of monitoring the state of the cutting tool edge, which forms optical radiation directed to the edge of the moving cutting tool, converts the reflected radiation into an electrical signal, measure the amplitude of this signal and the duration of the optical signal of the optical sensor, during which the maximum amplitude A of the signal of the optical sensor exceeds the level D of the voltage of the source of the reference voltage; the period T of rotation of the cutting tool is measured; t is the relative thickness of the tooth of the cutting tool t / T; the ratio of the relative thickness of the tooth of the cutting tool t / T to the maximum amplitude A of the optical sensor signal is calculated.

The goal is also achieved by those. that the device for monitoring the state of the cutting tool edge includes an optical sensor, a reference voltage source, a comparator, a peak detector, a dividing unit and a rotary sensor, with the output of the optical sensor connected to the inputs of the comparator and the peak detector, the output of the reference voltage source the output of the peak detector is connected to the first input of the dividing unit, the output of the comparator is connected to the second input of the dividing unit, the output of the rotary sensor is connected to the third input of the dividing unit, both outputs of the division unit are outputs of the device.

FIG. 1 shows a block diagram of the device; in fig. 2 is a diagram of a dividing unit.

The device for monitoring the state of the cutting tool edge includes an optical sensor 1, a voltage source 2, a peak detector 3, a comparator 4 dividing unit 5 and a rotary sensor 6, the output of the optical sensor 1 being connected to the inputs of the peak detector 3 and comparator 4, the source 2 output the reference voltage is connected to the second input of the comparator 4, the output of the peak detector 3 is connected to the first input of the dividing circuit 5, the output of the comparator 4 is connected to the second input of the dividing unit 5, the output

revolving sensor 6 is connected to the third input of dividing unit 5.

Block 5 division consists of the following elements: analog-to-digital converter 7, register 8, first reversible counter 9, first logic element 10 AND-NOT, first counter 11, first driver 12, first inverter 13, second inverter 14, second reversible counter 15 , RS flip-flop 16, second logical element 17 AND-NOT, third logical element 18 AND-NOT, frequency multiplier 19, second counter 20, reference oscillator 21. second driver 22, divider 23, with input of analog-digital converter 7 being the first input of block 5 division (Fig. 1), outputs ana logo-digital converter 7 is connected to the inputs of the register 8, the outputs of which are connected to the inputs of the first

reversible counter 9, the output of which is connected to the first input of the first logic element 10 AND-NOT, the output of which is connected to the counting input of the first counter 11, the output of the first driver 12

is the second input of the division unit 5 and is connected to the first input of the third NAND logic element 18, the output of which is connected to the counting input of the second counter 20, the outputs of which are connected to the inputs of the second reversible counter 15, the output of which is connected to the R input of the RS-trigger 16, the output of which is connected to the second input of the first logical element 10 AND-NOT, to the second input of the second logical element 17 AND-NOT, to the input of the second driver 22, the output of the rotary sensor 6 and the output of the divider 23 are connected to the third input of the division unit 5 and in dy frequency multiplier 19, whose output

connected to the second input of the third logical 18 NAND; besides, the output of the first shaper 12 is connected to the zeroing input of the first counter 11, to the input of the first inverter 13, the output of which is connected to

input divider 23. to the C input of the second reversible counter 15, to the S input of the RS flip-flop 16, to the input of the second inverter 14, the output of which is connected to the zero input of the second counter 20 and to the input of the register 8,

the output of the reference generator 21 is connected to the counting input of the first reversible counter 9 and to the first input of the second logic element 17 AND-NOT, the output of which is connected to the counting input of the second reversing counter 15, the C input of the first reversing counter 9 is connected to the output of the same counter.

The device works as follows

When rotating the cutting tool from the output of the optical sensor 1 receives an electrical signal. Each of the pulses of this signal corresponds to the passage past the optical sensor of the next tooth of the cutting tool. From the optical sensor 1, the signal enters the peak detector 3, the output signal of which characterizes the maximum amplitude A of the signal of the optical sensor 1. The signal of the optical sensor 1 also goes to comparator 4, where it is compared with the voltage D of the reference voltage 2. The output signal of comparator 4 characterizes the duration of the optical sensor signal of 1 ton LM, during which the maximum amplitude A of the signal of optical sensor 1 exceeds the level D of the voltage of source 2 of the reference voltage. The signal A of the optical sensor 1 is fed from the output of the peak detector 3 to the input of the division unit 5 and is converted by an analog-to-digital converter 7 into a code. The signal g of the optical sensor 1 is fed from the output of the comparator 4 to the input of dividing unit 5. At the falling edge of the signal T, the first driver 12 generates a pulse of positive polarity to zero the first counter 11, then use the same inverted second inverter 14 signal of the analog-digital converter 7 is written to the register 8 and serves as a reference code for the first reversible counter 9, which performs the function of frequency divider of the reference oscillator 21 by the code of the register 8, since the first reversible counter 9 has zero impulse and reference generator 21, and again enters the code register 8 by zeroing pulse supplied ne C-input of the first down counter 9. Thus, the output frequency of the first down counter 9 is inversely proportional to the maximum amplitude A of the optical sensor 1 and equal to fo / A. where fo is the frequency of the reference oscillator 21.

Information about the period T of rotation of the cutting tool comes from the revolving sensor 6 to the input of block 5, which is the input of frequency multiplier 19, the reference signal to the frequency multiplier 19 can come not only from revolving sensor 6, but for example from divider 23, which can be made in the form of a reversible counter, to the inputs of which a code corresponding to the number of teeth of the cutting tool is entered. The installation of this code can be done by a switch with a manual dialing, for example, a PC-10 switch. To counting input -1

pulses come from the output of the driver 12 through the inverter 13, and zeroing pulses from the output of O arrive at the C input of the same counter and to the input of the frequency multiplier 19. During the arrival at the input of unit 5 for dividing the signal, the magnitude of frequency multiplier 19 enters the input of the second counter 20 through the third logic element 18 AND-NOT the frequency multiplier 19 pulses, the multiplication factor K of which is selected in the order of 2000-4000. The code obtained in the second counter 20 is rewritten into the second reversible counter 15, where it is written off by pulses of the reference oscillator 21. As a result, a time interval t - K-- is formed at the output of the RS flip-flop. Where

T That

At B is the relative thickness of the tooth of the cutting tool. During this interval, the first counter 11 is filled with pulses of the first reversible counter.

9 with a frequency of fo. The time interval t is a function of the relative thickness of the tooth of the cutting tool and does not depend on the speed of rotation of the cutting tool, since

t1-

TO

Thus, at the output of the first counter 11, we get the quotient code from dividing the relative thickness of the cutting tool tooth g / T by the maximum amplitude A of the signal from the optical sensor 1., |

those. N1 K

t „B

At the same time

The falling edge of the output pulse of the RS flip-flop 16 generates a readiness signal of the B / A division result for entering the machine control circuit. During the machining of the part, the cutting tool rotates, and the next tooth of the cutting tool enters the visual field of the optical sensor 1, a pulse is formed at the output of the first shaper 12, which tilts the first counter 11, and the cycle for determining the edge parameters is repeated.

Claims (3)

Claim 1. A method for monitoring the state of a cutting tool edge, which forms optical radiation directed to the edge of a moving cutting tool, converts the reflected radiation into an electrical signal and measures the amplitude of this signal, characterized in that the edges of the cutting tool, additionally measure the duration m of the electric signal, during which its amplitude exceeds a predetermined level D, measure the speed of movement of the cutting tool ments and determining the degree of wear of the cutting tool in the amplitude of the electrical signal, the duration of r and velocity of movement of the cutting tool. 2. A device for monitoring the state of the cutting tool edge, containing an optical sensor, the output of which is connected to the input of the comparator, characterized in that, in order to improve the accuracy of control of the state of the edge of the cutting tool, it is provided with a voltage source, a peak detector, a dividing unit and a rotary sensor for communicating with a monitored cutting tool, the optical sensor output being connected to the inputs of the comparator and the peak detector, the output of the reference voltage source being connected ene to the second input of the comparator, the peak detector output is connected to the first input dividing unit, the comparator output is connected to the second input of the dividing unit, an output working sensor connected to the third input dividing unit dividing unit both outputs are the outputs of the device. 3. The device according to claim 2, that is, that the division unit is made in the form of an analog-digital converter, a register, a first reversible counter, and the first NAND logic element. the first counter, the first shaper, the first inverter, the second inverter, the second reversible counter. RS-flip-flop, the second logical element AND-NB, the third logical element AND-NOT. frequency multiplier, second counter, reference oscillator, second driver, divider, and the input of the analog-digital converter is the first input of the dividing unit, the outputs of the analog-digital converter are connected to the inputs of the register, the outputs of which are connected to the inputs of the first reversing counter, the output of which is connected to the first input of the first logical element IS-NOT, the output of which is connected to the counting input of the first counter, the output of the first shaper is the second input of the division unit and is connected to the first input of the third NAND logic element, the output of which is connected to the counting input of the second counter, the outputs which is connected to the inputs of the second reversible counter, the output of which is connected to the R input of the RS flip-flop, the output of which is connected to the second input of the first NAND logic element, to the second the input of the second logical element IS-NOT to the input of the second driver, the output of which is connected to the machine control circuit, the output of the rotary sensor and the output of the divider are connected to the third input of the division unit to the input of the frequency multiplier, the output of which is connected to the second input of the third logical element I- NOT, moreover, the output of the first shaper is connected to the zeroing input of the first counter, the input of the first inverter, the output of which is connected to the input of the divider, to the C input of the second reversible counter, to the S input of the RS trigger. the input of the second inverter, the output of which is connected to the zeroing input of the second counter and to the C input of the register, the output of the reference generator is connected to the counting input of the first reversible counter and the first input of the second NAND logic element whose output is connected to the counting the input of the second reversible counter. From the input of the first reversible counter is connected to the output of the same counter. FIG. 7