JPS63283846A - Measurement of tool cutting edge diameter - Google Patents

Abstract

PURPOSE:To permit the measurement in the installation state and secure high reliability by using the small-sized captioned device which can be easily handled, by detecting the shift quantity of the vibration of the tool cutting edge of a tool by a noncontact type stable shift sensor and amplifying the output and digital-converting said output. CONSTITUTION:The outside diameter of a rotary tool 3 on a main spindle is attached onto the position coordinate point of a detecting plate 24 fixed onto the table 5 of an NC machine tool, and the variation of the cyclic vibration of the detecting plate 24 which is due to the variation of the contact point of the cutter top edge is detected as a certain space displacement. A shift sensor 8 which possesses the high linearity is fixed oppositely to the detecting plate 24, and the space shift is detected, and then amplified by an insulation amplifying circuit 13 and digital-converted by an A/D converter 17, and the min. value is held in a bottom holding circuit 18, and the eccentricity quantity of the tool is calculated reversely, and the obtained value is added or subtracted from the radius of the tool which is memorized in a standard value memory 29, and the true diameter of the tool is obtained. Therefore, the cutting edge diameter of the tool 3 in the installation state can be measured easily with the small- sized device, and the high reliability can be obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for measuring the diameter of a tool cutting edge, and in particular, to measuring the diameter of a cutting edge of a tool mounted on a main shaft on a machine by using the movement of the machine. A tool that calculates the actual tool diameter value by measuring the run-out m of the tool edge when the spindle is reversed using a displacement sensor against the π difference tool diameter (nominal diameter) stored in the memory. This invention relates to a method for measuring the diameter of a cutting edge.

[Conventional technology]

Conventionally, one method of measuring the diameter of the tool cutting edge is shown in Fig. 7-
Is there a way to show it to people? This method consists of a rotating part that fixes the tool and holder together, a tie cell gauge that measures the diameter of the tool cutting edge, a signal that fixes this, and a feed screw that moves this table. It consists of a measuring scale that counts the amount of movement of the handle and the handle, and a measuring scale that counts the amount of movement of the handle.

In addition, as another method for measuring the tool cutting edge diameter, the seventh
There is a method shown in Figure B. This method consists of (b) a part that holds the tool and the holster in the turntable bag, a contact plate slide 11) facing the T-piece that measures the diameter of the tool cutting edge, a tJ, and the contact plate slide that opens and closes in conjunction with each other. It is composed of a rotor/pinio mechanism wheel, a measuring scale for counting the amount of movement of this contact plate slide, a display, etc.).

Next, the operation will be explained. One of the conventional methods is f
The method shown in Fig. f17-A is to move the stand by rotating the handle 67) to the cutting edge of a fixed tool, bring the tip of the Daicel gauge into contact with it, and then tighten and set 1.
Feed the architrave further until the needle of the Daicel gauge rotates to this 0 point. At this time, rotate the tool (b) so that the cutting edge touches the tip of the Daicel gauge. Ma1ko,
At this time, if it is a multi-edged tool, rotate the tool and while making contact with the Daicel gauge (G), find the cutting edge where the radial runout is the largest, and at this time the needle of the Daicel gauge will be at the 0 point. Turn the handle (B) once to move the architrave so that The amount of movement from the center of the tool at this time is read on a sub-length scale attached to the architrave and displayed on the display, and this value is multiplied to determine the diameter of the cutting edge of the tool.

Another conventional method, the method shown in No. 7 Inshino, is to fix the tool on a rotary table, open one contact plate slide β sword in advance, and contact the cutting edge of the tool. When the tool (B) is turned in the opposite direction, the cutting edge pushes the contact plate slide open and rotates until the contact plate slide stops moving. , since the opening amount of this contact plate slide gives the maximum diameter when the tool cutting edge rotates, when both contact plate slides are in complete contact and 1 time is O, the amount of movement of one side of the contact plate slide is This value is read on a measuring scale attached to the contact plate slide, and displayed as display 6, and this value is multiplied to be the diameter of the tool cutting edge to be determined.

[Problem that the invention seeks to solve]

The method shown in Fig. 7-A is the conventional film force method, but with this method, human error occurs in how to align the tool cutting edge point with the probe tip of the Daicel gauge, and - door η) When there is no contact, the value of the tool cutting edge diameter at fζ changes when the tool rotates in the state of contact positioning of the tool cutting edge in the axial direction, and the value obtained is r
This value also has a large error.

Furthermore, this method of measurement differs from the state in which the tool is mounted on the main spindle on the machine, and therefore the cutting edge rotational diameter during tool rotation cannot be obtained during machining using this tool. In particular, there have been problems such as the difficulty in accurately measuring the tool diameter during finishing machining.

Furthermore, in the method shown in Figure 7-B, the mechanism of the two contact plate slides must be functionally designed to slide even with a small force of η), so the reaction that the contact plate slides receive depends on the rotational speed of the tool. The force changes and the contact plate slide tends to open too far without making precise contact with the tool cutting edge. Figure 7 - Similar to the human method, measurement using this method differs from the state in which the tool is attached to the spindle on the machine, so it is difficult to accurately obtain the rotational diameter of the cutting edge when the tool rotates during actual machining. There is one problem, such as not being able to do it.

This invention was made in order to solve the above-mentioned problems, and it is possible to easily adjust the diameter of the cutting edge when the tool rotates with ease on the machine and with the same target tool as the actual machining tool mounted on the main axis. In addition to being able to measure, the measured value can be digitally converted and transmitted to machine control devices such as N (3 devices) to be used as a tool radius offset value.Furthermore, the measurement itself can be automatically performed by commands such as a tool cutting edge. The purpose is to obtain a diameter measuring device.

[First Means to Solve the Problem] The tool cutting edge diameter measuring device according to the present invention is fixed at a fixed position on a machine table, and the outer diameter of a rotary tool attached to a main shaft is brought into contact with a position coordinate point of a movable plate. , 80~(iQrp
By applying a low-speed reverse rotation of approximately 200 m, the movable plate vibrates periodically due to changes in the contact point of the tool cutting edge.A preload is applied to the slider that slides the movable plate with the iζ spring, and changes in this periodic vibration are controlled to a certain level. Taking it as a spatial displacement, a displacement sensor with high linearity is fixed facing the movable plate, and the displacement between the plates is detected, which is amplified and A/D converted.
By holding the minimum value, the tool bias is calculated backwards,
The true tool diameter is determined by adding or subtracting this value from the nominal diameter of the tool radius stored in the memory.

C et Cζ.

[Effect]

The method for measuring the diameter of a tool cutting edge in this invention applies a preload using a Cζ spring to bring a movable plate into contact with the cutting edge of a rotary tool, always faithfully reproducing the movement of the cutting edge as it rotates, and furthermore, The analog side C of the movable plate uses a displacement sensor with high linearity to accurately convert it as an inertial signal.
ζ Provide a certain space and fix it, and respond to this spatial displacement ♀
Obtain pressure force.

Further, this output is insulated and amplified, digitized by A/D conversion, and the maximum value of the change from the reference value y position 1it is obtained as a spatial displacement by a small value hold process. This stiffness is due to tool eccentricity, and this value is subtracted from the nominal value of the tool to be measured, that is, the nominal radius value, to obtain the actual value of the tool radius.

[Embodiments of the invention]

As an embodiment of the present invention, a tool cutting edge diameter measuring device using the tool cutting edge diameter measuring method lζ and τ is shown in FIG. In FIG. 1, (1) is the No. machine tool main spindle, and (2) is the tool cutting edge diameter measuring device. Furthermore, (3) is a tool holder.
1ζ installed tool, (5) is No. machine tool table,
(6) is a surf motor, (7) is a ball screw, @ is a numerical control device, ■ is a movement command, a paper tape with the tool diameter base j value punched out, the handle is a movement command, and a key fob for manually keying in the tool diameter, etc. The fourth is the memory that holds the base data.

The tool edge diameter measuring device (2) is equipped with a tool edge runout detector (
4), Displacement sensor (8), perforation conversion circuit (9), its calibration circuit @, variable resistor αQ for zero adjustment, variable resistor αV for linearity adjustment, insulation width circuit (to), its flexible circuit Qe, variable resistance for zero adjustment 04, variable resistance for blood related gradient adjustment a9, A/D converter αη, bottom hold circuit (to), binary value conversion circuit a9, and L10 output Kake-
A pull button is provided for starting the A/In' conversion.

The tool tip run-out detector is attached to the ball shaft and is installed on one tool (3).
By contacting the detection plate (goods) with the cutting edge, the runout displacement during n-turn is detected by the displacement sensor (8) and output as a change in the eddy current value, and this output amount is determined by the ability of (9). The signal passes through the current voltage conversion circuit, and further passes through the insulation amplification circuit Q3 that blocks noise and amplifies the output, and then enters the α-reverse A/D9 converter. Furthermore, (g) is a bottom hold circuit that holds the minimum value of this displacement amount, and then a binary conversion circuit α starvation circuit (7) that converts it into binary data and an A/D
The input cable (to) receiving the conversion activation signal is connected to the A/l) converter of Q7).

As shown in Figure 4-A, the y is mounted on the main shaft (1),
= Fast forwarding speed of the tool (3) via Harado - η〉 to the intermediate point - (4!1, positioning to the approach point, moving to the basic position displacement point @η, at slow speed (7) Positioning.The is position amount 51J is 1/2 of the full scale of the displacement sensor.This state is shown in Figure Ia1Eζ and there is a distance 7' from which the main shaft (1) is mechanically moved. Reverse at the lowest speed specified and come into contact with it and detect one. (c)
The movable plate 4 vibrates periodically. This tool edge run-out detector (4) has a pattern number ζ whose details are shown in Fig. 2, and a detection plate that makes surface contact with the tool edge, and a movable plate that fixes this, on a roller slide base (as shown in Fig. 2). ), and there is also one reference plate fixed to the same base lζ in the opposite position, and one spring C3z is provided to preload this roller slide base towards the center of the tool. Therefore, when the tool is rotated in the reverse direction while in contact with the tool cutting edge and preload is applied, the detection plate (goods) and movable plate (c) move following the Nl contact point on the cutting edge, and this moves to the roller slide base (a).
It will make the whole thing vibrate. This vibration generally has a period 'rsec determined by the tool blade height z and the spindle rotation speed hrpm.
It becomes a periodic vibration with . The period T in this case can be found as follows. Therefore, when the low Z, N last slide base (to) oscillates periodically, there will be 22 rl between the base hawk board (goods) and the father position yansa (8)! ll distance is
It is inversely proportional to the period T, and when the tool tip runout is at its maximum, the output of the displacement sensor (3) is at its minimum. The output of the displacement sensor (3) from the tool edge run-out detector (4) when the tool (3) is reversed is the amount of change in eddy current, so this is converted into the 1W current pressure conversion circuit ( 9) and l)
Convert to O@pressure amount. An example of the output waveform at C is shown in FIG. This example is when the tool of a two-sided end mill is held constant.The output proportional to the difference in distance from the center of rotation of the two cutting edges is observed, and the minimum value of this displacement is -. , displacement amount Q of the standard cutting edge position when the nominal diameter value
One scream of the sword corresponds to the eccentricity of the cutting edge. However, the displacement singing pressure j
1& is several mV and is easily influenced by external noise. Also, remove 6ζ noise, connect it to the insulation amplification circuit side to amplify it, and perform amplification. After 1, A/ l) i converter α
η to a decimal value, a bottom hold circuit to hold the minimum displacement value, and after converting this value to a binary 11-bit, 1-t string, it is converted into a per-rel UM/UFF signal in the numerical controller C21). is supplied to the macro input interface surface. In response to this signal, the NO tape is input from the keyboard to the memory 4 of the numerical control device &υ, and the process of adding or subtracting from the tool nominal radius value is performed by Δ
It is possible to calculate the tool cutting edge radius value with respect to the spindle [g1 rotation center] by inputting data from the tool cutting edge diameter measuring device (2) set in a C program as necessary.

In the above embodiment, the shape of the tool edge runout detector (4) is rectangular, but it may be round.

The movable plate (to) and the base plate (2) are integrally made of a single round bar, and the slide portion uses a cylindrical slide with a built-in ball bearing, producing the same effect as in the above embodiment.

Furthermore, even for machine tools whose spindles are oriented horizontally, such as horizontal machining centers, it is possible to increase the splash pressure inside this detector and use a blower, screwdriver, or stand to mount the detector vertically. This embodiment has the same effect as the above embodiment.

〔Effect of the invention〕

As described above, according to the present invention, the runout of the tool cutting edge can be reduced by the second
By using a detector like the one shown in the figure to detect the amount of displacement with a non-contact, stable single displacement sensor, and further amplifying the output and digitizing it, the device can be made cheaper than conventional ones, and it is even more cost-effective. ,0
．． Measurement accuracy up to 0.005ff can be obtained. Furthermore, the detector body has become smaller, measuring approximately 100 x 50 x 100 H.
It is easy to handle, and it is possible to measure the diameter of the cutting edge of the tool when the tool is actually installed on the machine.It also has the effect of providing a highly reliable diameter correction value during actual machining.

[Brief explanation of the drawing]

FIG. 1 shows the equipment configuration and (B) schematic diagram of a tool cutting edge diameter measuring device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a tool cutting edge runout detector used in an embodiment, and Figure 4-B is the displacement voltage output waveform of the tool edge run-out detector during tool diameter measurement, which is used to explain the operation of the tool edge diameter measuring device. 7th tool positioning route diagram used for r-measuring to explain the operation of the diameter measuring device
FIG. 8 and FIG. 7-B are conceptual diagrams showing a conventional method for measuring the diameter of a cutting edge of a tool. In the figure, (1) is the No. machine tool spindle, (2) is the tool cutting edge diameter measuring device, (3) is the tool holder equipped with f-coni, (5) is the ha machine tool table, and (2) is the numerical control. The device is a memory that holds standard data, (4) is a tool tip runout detector, (8) is a displacement sensor, (9) is a commercial pressure conversion circuit, @αG is a calibration circuit, and a0α◆ is a zero egg. variable resistance, Ql) tXj is variable resistance for linearity gradient adjustment, αh
is a power converter, (to) is a bottom hold circuit, and α4O binary value conversion circuit.

Claims (1)

[Claims] A preloaded movable plate is brought into contact with the tool cutting edge of a rotary tool attached to the main shaft, and the tool is given reverse rotation, and the movement of the movable plate that is moved by the runout of the tool cutting edge at that time is as follows:
Detected by a linear displacement sensor, the output value proportional to the spatial distance between the movable plate and the displacement sensor is digitally converted, the minimum value of the value is held, and the measurement target is stored in memory in advance. A method for measuring a tool cutting edge diameter, characterized in that the true value of the tool cutting edge diameter is determined by adding or subtracting from the nominal value of the tool radius.