JPH08351B2 - Blade position measurement method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool edge position measuring method for a NC machine tool, for example, a tool having a tool edge away from the center of the spindle in a boring process of a machining center or a tool capable of controlling the U axis by the NC axis. .

2. Description of the Related Art A tool mounted on the spindle of a machining center and having a cutting edge away from the center of the spindle or a tool having U-axis control changes slightly when the cutting edge is replaced, the tool holder is replaced, or the setting position of the tool holder is shifted. Moreover, the position of the cutting edge gradually changes from the center of the spindle due to wear caused by machining. Conventionally, it was difficult to measure on the machine base to accurately grasp the position of the cutting edge. Therefore, remove the tool holder and use the tool presetter outside the machine to measure the U-axis diameter of the cutting edge, measure the hole that has been machined once with a cylinder gauge, etc. to accurately grasp the cutting edge position. Although the position of the cutting edge was corrected, a subtle error for reattaching the tool holder was unavoidable and operator intervention was required. To eliminate this inconvenience, Japanese Patent Laid-Open No. 61-249249 discloses a device for measuring the cutting edge by providing a touch sensor.

Problems to be Solved by the Invention The touch sensor is usually provided on the table or the like of the machine, and is located at a position where it does not interfere when setting the work and setup on the table and does not interfere with the tool during machining. It needs to be provided. In particular, during finish cutting, the cutter needs to be moved until it is separated from the work in order to align the cutting marks, so that amount must be taken into consideration. For this reason, it is provided near the stroke end of the machine.

For this reason, when the U-axis controllable tool holder is used to shift the position of the U-axis edge from the center of the main axis, the stroke is not enough even if the main axis of the machine is moved to the stroke limit of the X-axis or Y-axis There was an inconvenience that the sensor could not be contacted and measurement could not be performed. If the touch sensor is configured to be moved auxiliary by a cylinder or the like to compensate for the shortage of stroke, a complicated and expensive device is required, which is not preferable.

An object of the present invention is to provide a blade edge measuring method capable of compensating for the shortage of the stroke without lengthening the axial stroke or providing another auxiliary device, and capable of accurately measuring the blade edge position.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention is a method for measuring the position of a tool blade edge away from the center of a spindle of a machine tool whose position can be controlled in the X, Y, and Z axes. The back surface of the bite holder mounted on the main spindle is brought into contact with a touch sensor which is provided in advance so as to match the main spindle center and output a touch signal at the position of zero Y-axis. The present value A is stored, and the present value A and the known distance POST value B between the cutting edge and the back surface of the cutting tool holder are used to calculate AB, and the distance C from the center of the spindle to the cutting edge is obtained. is there.

Also, in the U-axis control tool edge position measurement method that can adjust the distance from the spindle center of the machine tool that can control the X, Y, Z axes, etc., the touch signal that matches the spindle center in advance at the Y axis zero position Is attached to the spindle with a touch sensor provided so that the Y axis is moved close to the tool edge where the spindle center position is U axis zero, and the current value E of the stopped Y axis is stored. Then, store the current value F of the U-axis,
Next, move the U-axis to bring the cutting edge into contact with the touch sensor,
The current value G of the axis is stored, and the distance H from the cutting edge set at the F position to the center of the spindle based on the values F, G, E is FG + E.
This is obtained by the calculation of.

Further, in a U-axis control tool edge position measuring method in which the distance from the spindle center of a machine tool capable of position control of the X, Y, Z axes, etc., can be adjusted, the Y axis coincides with the spindle center at the Y axis zero position, and The current value J of the U-axis of the tool cutting edge with the main shaft center position set to U-axis zero is stored by moving the U-axis in the direction away from the touch sensor provided so that the touch signal is output.
The X-axis and Z-axis are moved to a position where the blade tip can touch the touch sensor, the U-axis is moved by the movement range of the U axis in the direction in which the blade tip touches the touch sensor, and the current value K of the U-axis at the moving position is stored. Next, the blade tip is moved along the Y axis to contact the touch sensor, and the current contact value L of the Y axis is stored. Based on the values J, K, and L, the distance between the blade edge at the position of the current value J of the U axis and the center of the spindle. M is obtained by the calculation of J−K + L.

Action of Claim 1 Method of measuring with Y-axis In FIG. 5 showing a flow chart, in step S1, the tool mounted on the spindle is moved and retracted to the end of the movement range (hereinafter referred to as stroke) by Z-axis + direction movement. In step S2, the spindle 2 is rotated 180 ° from the tool exchange position so that the back surface 4a of the bite holder 4 faces the touch sensor 6 (FIG. 2).

In step S3, the bite holder 4 is touch sensor 6
The X-axis and the Z-axis are moved at a position where they do not come into contact with the touch sensor so that they can come into contact with the touch sensor (FIG. 3). At this time Z
The axis is moved by, for example, 8.000 of the tool length correction value + the distance (PTOF) in the Z-axis direction from the tip of the cutting edge 5 to the back surface 4a.

In step S4, the back surface 4a of the bite holder is brought into close contact with the touch sensor 6 by moving the Y axis (FIG. 4). The current value A, which represents the distance from the center of the Y-axis, for example, 20.0
Store 00 in NC.

In the following, all current values represent the distance from the center of the main axis.

In step S5, the distance C from the center of the spindle to the tip of the cutting edge 5 is calculated based on the POST value B stored in advance, for example, 9.150, C = AB = 20.000 = 9.150, and C = 10.850.
Ask for.

Action of claim 2 Method of measuring with U-axis and Y-axis In FIG. 6 showing a flowchart, step S10
At, the tool mounted on the spindle is moved to the stroke end by moving in the Z axis + direction. In step S11, the spindle 2 is indexed, and the U-axis of the tool mounted on the spindle 2 is parallel to the measurement direction of the touch sensor 6 and the cutting edge 5 is opposed. In step S12, the X-axis and the Z-axis are moved so that the tip of the cutting edge 5 can contact the touch sensor 6. In step S13, the Y-axis is moved to near the contact with the touch sensor 6 (FIG. 7). The current value E of the Y axis (for example, -20.000) is stored. In step S14, the current value F of the U axis (for example, -30.000) is stored. At this time, the cutting edge 5 is preferably set in advance in a position as close as possible to the target machining radius for machining by moving the U axis. In step S15, the U-axis is moved to bring the cutting edge 5 into contact with the touch sensor 6 to stop the shaft, and the present value G of the U-axis at the time of contact (for example, −25.01).
0) is memorized. (Fig. 8). In step S16, NC the distance H = FG + E between the tip of the cutting edge 5 and the center of the spindle 2.
Calculate H with the device (eg -30.000 + 25.0)
10−20.000 = −24.990). After obtaining the distance H in this way, the U-axis is returned to the original position F and the value of H is compared with the value of F. If necessary, the origin of the U-axis is offset so that the value of F becomes the value of H. Or, it is treated as a broken tool.

Action of claim 3 Method for measuring with U axis and X, Y, Z axes In FIG. 9 showing a flowchart, step S20
At, the tool mounted on the spindle is moved and retracted to the Z-axis + direction stroke end. In step S21, the spindle 2 is indexed so that the tip of the cutting edge 5 faces the touch sensor 6 side (tenth step).
Figure). In step S22, the cutting blade 5 for the U-axis stroke
The Y-axis is moved in a direction away from the touch sensor 6 so as to retract (FIG. 11). In step S23, the current value J of the U axis (for example, -30.000) is stored. Step S2
At 4, the X-axis and Z-axis are moved so that the tip of the cutting edge 5 can contact the touch sensor 6. In step S25, the U-axis is moved to move the cutting edge 5 to the touch sensor 6 side to the U-axis stroke end or a fixed position near the stroke end, and the current value K (for example, +8.000) of the U-axis is stored ( 12th
Figure). In step S26, the Y-axis is moved to the touch sensor 6 side, the tip of the cutting blade 5 is brought into contact with the touch sensor 6 to stop the axis, and the current value L at the time of contact at Y (for example, 13.010) is stored ( (Fig. 13). In step S27, the distance M between the tip of the cutting edge 5 and the center of the spindle is calculated by M = JK + L to obtain M (for example, -30.000-8.000 + 13.010 = -24.990). The U axis is returned to the J position and the Y axis is returned to the L position, the value of M is compared with the value of J, and the origin correction of the U axis or the tool breakage is processed according to the comparison.

Example A machining center has a well-known horizontal type, for example, Japanese Patent Laid-Open No. 61-
As described in No. 24949, the X-axis, Y-axis, and Z-axis position control is possible by NC control of the spindle and table saddle. As the U-axis control tool, a well-known and commercially available tool can be used. For example, as described in JP-A-61-249249, a bite holder with a cutting edge is perpendicular to the tool holder axis (U
It is provided so that it can move in the direction of the axis, and when the tool is mounted on the spindle, the drive unit equipped on the spindle head and the drive system path are connected and positioned by NC. 1 is a spindle head whose position is vertically controlled (Y-axis) in a column (not shown), 2 is a spindle which is supported in the horizontal (Z-axis) direction so that the spindle head can rotate and index, and 3 is stored in a magazine (not shown) The U-axis tool holder 4 mounted on the spindle 2 by the tool changer is in a direction perpendicular to the axis of the tool holder 3 and in this example, Y
A bite holder that can be moved parallel to the axis (called the U-axis) and is connected to the NC drive system path when the spindle is attached to control the U-axis. Correct measurement values can be obtained when the back surface 4a contacts the touch sensor. It is finished parallel to the tool holder axis. Reference numeral 5 is a cutting blade attached to the tip of the bite holder, and reference numeral 6 is a touch sensor attached to the end of a table (not shown) whose movement is controlled in the horizontal (X-axis) direction so that the Y-axis direction is the acting direction. To mount the touch sensor 6, a straight test bar whose diameter is accurately measured is attached to the main shaft 2, the main shaft is moved downward in the Y-axis direction to make contact with the touch sensor, and the current value of the Y-axis at the contact position. The value on the Y-axis obtained by subtracting 1/2 the diameter of the test bar from is set as zero. Also, attach a tool holder, position the center of the spindle at the position of zero value on the Y-axis, and make the cutting edge 5 face the touch sensor.
The axis is controlled so that the cutting edge comes into contact with the touch sensor, and the value of the U axis at the contact position is set to zero. Further, the tool holder 3 accurately measures the dimension between the tip of the cutting blade 5 and the back surface 4a of the bite holder 4 by using a presetter or the like before storing in the magazine, and the value is set as the POST value B in the NC device. There is something to remember.

In this example, the U axis is described as being parallel to the Y axis, but the touch sensor performs the same measurement with the X axis control instead of the Y axis control with the X axis direction of table movement as the detection direction and the U axis as the X axis direction. be able to.

Effect As described above in detail, in claim 1, the shortage of the control axis stroke can be compensated by simply reversing the bite holder, and the touch sensor can be placed in a place where it does not interfere with the work on the tape, and the restriction on the processing range is reduced. be able to.

In the second aspect, the present values F, G, E can be accurately detected, so that the position of the cutting edge can also be accurately measured. further,
Since the U-axis can achieve measurement of the cutting edge largely deviated from the center of the spindle with respect to the touch sensor provided near the stroke end, there is an effect that the cost is not increased easily.

In the third aspect, as in the second aspect, the current values J, K, L can be accurately detected, so that the distance M between the cutting edge and the center of the spindle can be accurately measured. Further, there is an effect that the U axis is used and the cost is not increased.

[Brief description of drawings]

1 is a diagram showing a U-axis tool and a touch sensor, FIG. 2 is a diagram in which the bite holder is rotated 180 °, FIG. 3 is a Z-axis positioning diagram, and FIG. 4 is a diagram in which the back face is in contact with the touch sensor. , FIG. 5 is a flow chart of claim 1, FIG. 6 is a flow chart of claim 2,
FIG. 7 is a diagram showing a U-axis tool and a touch sensor of claim 2,
FIG. 8 is a view in which a cutting blade is brought into contact with a touch sensor, FIG. 9 is a flow chart of claim 3, FIG. 10 is a view showing a U-axis tool and a touch sensor of claim 3, and FIG. 11 is a Y-axis. FIG. 12 is a diagram in which the cutting blade is moved away by control, FIG. 12 is a diagram in which the cutting blade is moved close to the U-axis stroke end, and FIG. 13 is a diagram in which the cutting blade is brought into contact with the touch sensor by Y-axis control. 2 ... spindle, 3 ... tool order 4 ... bite holder, 5 ... cutting edge 6 ... touch sensor

Claims (3)

[Claims] 1. A method for measuring the position of a tool edge away from the center of a spindle of a machine tool capable of position control of X, Y, Z axes, etc.
The back surface of the bite holder that has been axially moved and attached to the spindle is brought into contact with a touch sensor that is preliminarily aligned with the spindle center at the Y-axis zero position and outputs a touch signal. The present value A representing the distance is stored, and the present value A and the known distance POST value B between the cutting edge and the back surface of the bite holder are used to calculate AB, and the distance C from the spindle center to the cutting edge is calculated. A method for measuring the position of a cutting edge, which is characterized in that 2. A U-axis control tool edge position measuring method capable of adjusting a distance from a spindle center of a machine tool capable of position control of X-, Y-, Z-axes, etc., in which the Y-axis zero position and the spindle center are aligned in advance. In addition, the touch sensor provided to output the touch signal is attached to the spindle, and the Y-axis is moved to the vicinity so that the tool edge with the spindle center position of the U-axis being zero can come into contact, and the Y-axis currently stopped. The value E is stored, then the current value F of the U-axis is stored, and then the blade tip is brought into contact with the touch sensor by moving the U-axis,
The current value G of the U-axis is stored and F is calculated based on the values F, G, E.
The distance H from the cutting edge set to the position to the center of the spindle is F-
A method for measuring the position of a cutting edge, which is obtained by calculating G + E. 3. A U-axis control tool blade edge position measuring method capable of adjusting a distance from a spindle center of a machine tool capable of position control of X, Y, Z axes, etc. And the current value J of the U-axis of the tool edge with the U-axis set to 0 for the main axis center position is stored by moving the U-axis in the direction away from the touch sensor provided so as to output a touch signal. The X-axis and Z-axis are moved to a position where the blade tip can touch the touch sensor, the U-axis is moved by the movement range of the U axis in the direction in which the blade tip touches the touch sensor, and the current value K of the U-axis at the moving position is stored. Next, the blade tip is moved along the Y axis to contact the touch sensor, and the current contact value L of the Y axis is stored. Based on the values J, K, and L, the distance between the blade edge at the position of the current value J of the U axis and the center of the spindle. Blade edge position characterized in that M is calculated by the calculation of J-K + L Measuring method.