JPH0550361A - Tool center height measuring device - Google Patents

Abstract

PURPOSE:To provide a center height measuring device, capable of displaying any center height errors in a cutting tool set tool rest in a digital manner so easily and quickly. CONSTITUTION:A touch sensor 3, having two measured surfaces 3a, 3b formed in a circular arc of a diameter D centering on a position decentered as far as L to the center of a mount, is installed in a tip of a sensor mount 2, while the center mount 2 is held concentrically with this machine chuck, and a touch sensor axial line a-a is set in parallel with an X-axis on the basis of two-way taking plane 2a. Then, a cutting edge position X at a time when the edge of a cutting tool T comes into contact with the measured surface (a) by means of movement of a tool rest to the side of an X-axis direction sensor, is read out, is read, finding the center height of the tool to the circular center from D, X by operation, and a center height error found out by subtracting an eccentric value L from this center height is digitally displayed on a cathocl0ray tube, thus thickness of a floorplate is changed as much as the displayed value, regulating the center height of the cutting tool.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for measuring the core height of a cutting tool attached to a tool rest in an NC lathe.

[0002]

2. Description of the Related Art In turning processing, if the core height of the cutting tool is not accurately matched, a dimensional error or a shape error will occur during step processing as shown in FIG. 7 or spherical surface processing as shown in FIG. Since it appears, it is considered that the core height management of the bite is one of the important factors. Conventionally, the core height adjustment method of this cutting tool is such that rough setting is performed by a simple gauge or the like when mounting the cutting tool, and then the end surface of the workpiece 101 is cut as shown in FIG. 9 until the uncut amount 102 is exhausted. The core height was adjusted by adjusting the thickness of the.

[0003]

The method for adjusting the core height of the cutting tool described in the prior art requires labor and time for adjusting the thickness of the floor plate by cutting the end face of the work, and moreover, the work. There is a problem that some end surfaces cannot be trial-cut. The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide an apparatus capable of digitally measuring the core height of a cutting tool set on a turret of an NC lathe. To do.

[0004]

In order to achieve the above-mentioned object, a core height measuring device of a bite according to the present invention is a touch sensor having a measuring surface formed in an arc of a predetermined diameter at the tip of a main shaft, wherein the center of the arc is A predetermined eccentric amount is provided in the direction perpendicular to the X-axis with respect to the center of the main axis, and the sensor axis is provided so as to face the X-axis direction, and the cutting edge of the cutting tool comes into contact with the touch sensor to output a signal. A means is provided for calculating a core height error based on the predetermined diameter and the amount of eccentricity from the current X-axis value of the cutting edge at that time.

[0005]

When the tool tip is brought into contact with the sensor formed on an arc surface of diameter D eccentric to the center of the spindle in the direction perpendicular to the X axis by a diameter D and oriented in the X axis direction, the tool rest moves along the X axis. The X position of the cutting edge is read, the core height of the cutting tool to the center of the circular arc is calculated from the numerical values of X and D read by calculation, L is subtracted from the calculated value to calculate the core height error, and this is displayed on the CRT.
Then, the core height of the cutting tool is adjusted by changing the thickness of the floor plate by the displayed core height error.

[0006]

EXAMPLES Examples will be described with reference to FIGS. A chuck 1 fitted to the tip of the main shaft of a known NC lathe.
The sensor mounting base 2 is concentrically gripped by the grip claw 1a of the above, and the touch sensor 3 is fixed to the tip of the mounting base 2. The mounting base 2 has a two-way chamfering plane 2a in the X-axis direction cut on the central collar portion, and the measurement surface 3a of the touch sensor 3 is
3b is formed in an arc surface having a predetermined diameter D centered on a position parallel to the two-way flat surface 2a and eccentric by a predetermined amount L in the direction perpendicular to the X-axis with respect to the center of the main axis. In order to set the axis aa of the sensor accurately in the X-axis direction, the rotation angle of the main shaft is adjusted with the two-way flat surface 2a as a reference. Touch sensor 3
For example, a commercially available tool such as a tool sensor manufactured by Metrol that outputs a touch signal when the cutting edge of the cutting tool comes into contact with the measuring surface can be used, and the arcs of the measuring surfaces 3a and 3b are accurately formed to have a predetermined diameter D. There is.

On the other hand, in the tool rest 4 movably provided along the guide in the X-axis direction on the carriage which is movable in the Z-axis direction,
A turret 5 is provided so as to be turnable and indexable in a plane perpendicular to the axis, and a bite T is detachably attached to a plurality of tool attachment stations provided on the outer periphery of the turret 5. The tool rest 4 is moved and positioned by a servo motor 6 via a ball screw 7, and a position detector 8 is concentrically incorporated in the servo motor 6.

The block diagram portion of FIG. 5 is an excerpt of the circuit according to the present invention in the NC, and the operation command input unit 11 is
A portion for outputting a calculation command by the push button or the manual data input function, the arc diameter storage unit 12 is the touch sensor 3
The arc diameter D of the measurement surfaces 3a and 3b is stored, and the eccentricity storage 13 stores the eccentricity L of the touch sensor 3 with respect to the center of the spindle. The core height calculation unit 14
By the calculation command from the calculation command input unit 11, the arc diameter D, the eccentricity L, and the X-axis detection position X when the position detector 8 is touched are read and the length relationship of each side of the right triangle shown in FIG. From the following expression L ² = (D / 2) ² − (X / 2) ² , which represents the X-axis detection position when the core height is different as shown in FIG.
If the value is 1, the core height L1 with respect to the center of the arc at this time is calculated, and the difference between the core height L1 and the predetermined eccentricity L is calculated to calculate the core height error L2. The core height display unit 15 is a portion that receives the output signal of the core height calculation unit 14 and digitally displays the core height error on the screen of the CRT 16. The touch signal display unit 17 receives the touch signal from the touch sensor 3 and displays the CRT 16 screen. This is a portion that displays that the blade edge has touched the sensor by the top or the buzzer.

The operation of this embodiment will be described below with reference to the flow chart of FIG. In step S1, the mounting base 2 having the touch sensor 3 is attached to the grip claw 1 of the spindle chuck 1.
After confirming the presence or absence of shake by gripping at a, the rotation angle of the main shaft is adjusted so that the sensor axis center line aa accurately faces the X-axis direction with reference to the two-way plane. In step S2,
By manual operation of the pulse handle etc. on the NC operation panel, the Z-axis is positioned so that the Z-axis position of the tip of the bite T is almost on the extension line of the sensor axis center line aa, and the tool rest 4 is moved by the X-axis. The bite T is moved to the touch sensor side. In step S3, whether or not a touch signal is output during the movement of the X-axis is confirmed on the screen of the CRT 16 or by a buzzer sound. If NO, the process returns to step S2, and if YES, the X-axis is performed on the spot in step S4. Stop feeding.

Next, in step S5, a calculation command is issued from the calculation command input unit 11, and in step S6,
The core height calculation unit 14 reads the diameter D from the arc diameter storage unit 12 and the eccentricity amount L from the eccentricity amount storage unit 13, and the step S
In 7, the position detector 8 reads the detected position X at the time of touch into the core height calculation unit 14. Next, in step S8, the core height error L2 is obtained by calculation from the values of D, L, and X read by the core height calculator 14, and in step S9, the value of the core height error L2 is digitally displayed on the CRT 16. The measuring surface 3a of the touch sensor 3 is for a normal cutting tool, and the measuring surface 3b is for a reverse cutting tool. Further, it is assumed that the X-axis position of the cutting edge is tool-corrected so as to be exactly zero at the center of the spindle.

[0011]

Since the present invention is configured as described above, it has the following effects. A touch sensor having an arc surface with a predetermined diameter on the main shaft is eccentric to the center of the main shaft in a direction perpendicular to the X axis by a predetermined amount, and the sensor axis is X.
The tool is mounted so that it is oriented in the axial direction, and the X-axis movement of the cutting tool set on the tool post is stopped by the signal when the cutting edge comes into contact with the touch sensor. Also, since the core height error is calculated from the predetermined eccentricity amount and displayed digitally on the CRT screen, the core height can be measured easily and in a short time, and the shape accuracy during spherical surface machining is improved. , It becomes easy to control the diameter dimension during step processing.

[Brief description of drawings]

FIG. 1 is a side view of a touch sensor portion of a cutting tool core height measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a top view of FIG.

FIG. 3 is a front view of the touch sensor showing a state in which the center height of the cutting tool is accurately aligned with the center of the spindle.

FIG. 4 is an explanatory diagram of an equation for obtaining a core height error that represents a case where the core height of the cutting tool is low.

FIG. 5 is a block diagram of a core height error calculation circuit of a cutting tool including diagrams of a partial touch sensor and a tool rest of the present embodiment.

FIG. 6 is a flow chart of the operation of this embodiment.

FIG. 7 is a diagram showing stepped cutting cited in the related art.

FIG. 8 is a diagram showing spherical surface cutting cited in the related art.

FIG. 9 is an explanatory diagram of a conventional method for obtaining a core height error of a cutting tool by end face cutting.

[Explanation of symbols]

2 Mounting base 3 Touch sensors 3a, 3b Measuring surface 4 Turret 5 Turret 14 Core height calculation unit T bit D Arc diameter of measuring surface L Eccentricity amount L2 Core height error

Claims (1)

[Claims] 1. A device for measuring the core height of a cutting tool attached to a tool rest in an NC lathe, comprising a touch sensor having a measuring surface formed in an arc of a predetermined diameter at the tip of the spindle, wherein the arc center is the spindle. When a signal is output when the cutting edge of the cutting tool comes into contact with the touch sensor and has a predetermined eccentricity in the direction perpendicular to the center and the sensor axis is oriented in the X-axis direction. A core height measuring device for a bite, comprising means for calculating a core height error based on the predetermined diameter and the amount of eccentricity from the X-axis current value of the cutting edge.