JPH03228571A - Nc grinder and measurement of machine inside thereof - Google Patents

Abstract

PURPOSE:To make a grinding allowance the minimum necessary and to shorten grinding time, by providing grindstone shaft, etc., bite, etc., and a measuring instrument at a turret indexing position on a turret grindstone post. CONSTITUTION:A main shaft base is positioned at the external polishing position at the external polishing time and at the internal polishing position at the internal polishing time with the selection of the position in the X axial direction respectively. The necessary cutting is then performed by indexing the bite 13 of a turret grindstone post for a gripped work and grinding is then performed with the indexing of a turret grindstone post 9 on X/Z axes by indexing grindstone shafts 10, 11. Various measurements are performed with a measuring instrument 12 by indexing the turret grindstone post 9 prior to processing or after completion. On this measurement kind various ones necessary for the work accuracy of a work are carried out.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an NC grinding machine and an in-machine measurement method thereof.

BACKGROUND OF THE INVENTION Conventional NC grinding machines have not performed any cutting process other than grinding. Furthermore, conventionally, with the outer diameter sizing device, inner diameter sizing device, and end face sizing device built into the grinding machine, it was possible to measure only one location with one measuring device. Furthermore, the measurement range was widened, and by using it in combination with a switching unit, it was possible to measure several types of diameters.

Problems to be Solved by the Invention Multi-tasking machines such as machining centers have wide market potential in machine tools, but there is nothing like this for grinding machines. In addition, different measuring instruments are required to measure various types of measurements such as inner diameter, outer diameter, end face step, straightness, end face runout 1 cylindricity, inner diameter step, outer diameter step, machining allowance, diamond correction tool position, and grinding wheel dimensions. Therefore, installing them on this machine has various problems such as installation space, interference with other instruments, and cost.

The present invention was made in view of the problems of the conventional technology, and its purpose is to provide an NC grinding machine with multiple functions and a single measuring instrument before and after grinding to improve the quality of products.
The purpose is to provide an in-machine measurement method that can check the accuracy of various types of tools.

Means for Solving the Problems In order to achieve the above-mentioned objects, the present invention provides a headstock positioned in the X-axis direction at an internal grinding position and an external grinding position, a table movable and positioned in the X-axis direction, and the table. The turret grindstone head is provided with a turret whetstone head that is moved and positioned in the X-axis direction above the turret whetstone head, and the turret whetstone head is provided with a whetstone shaft, etc., a cutting tool, etc., and a measuring instrument at the turret indexing position.

It also enables various measurements with one measuring instrument.

For external grinding, the headstock is in the external grinding position, and for internal grinding, the headstock is in the internal grinding position. Select and position the position in the X-axis direction, and index the cutting tool of the turret grindstone against the grasped workpiece to find the required position. After cutting, the grinding wheel is indexed and the sag is removed.
Grinding is performed by controlling the upper tool rest along the X-Z axes. Before or after machining, the turret tool rest is indexed and various measurements are performed using a measuring instrument. Various types of measurements are performed that require precision in machining the workpiece.

EXAMPLES Hereinafter, examples of the present invention will be explained based on FIGS. 1 and 2.

In an NC grinding machine, a headstock lower base 2 having a parallel guide surface in the X-axis direction on the upper surface is fixed to the left end of the upper surface of the head 1, and a headstock 3 on which a main shaft in the X-axis direction is rotatably supported. is slidably mounted. The rotation of the main shaft is such that a rotation speed suitable for grinding and a rotation speed that allows cutting with a cutting tool are obtained. Then, the headstock 3 is moved to two positions, an inner grinding position and an outer grinding position, by a hydraulic cylinder device 4. A chuck 5 is fitted onto the tip of the main shaft to grip the workpiece and apply rotation to it. Headstock 3 of bed 1
A table 6 is slidably placed on the X-axis direction guide surface on the right side of the table 6, and its movement and positioning is controlled by a motor feed screw (not shown). A lower grindstone stand 7 is slidably mounted on a parallel guide surface in the X-axis direction on the table 6, and its movement and positioning is controlled by a feed screw 8 by a motor (not shown).

A turret whetstone head 9 is provided on the lower whetstone stand 7 so as to be able to rotate and index the position by 90''.This turret whetstone head 9 has a built-in type whetstone shaft 10 which can be used for internal and external grinding or is exclusively for internal grinding and has a built-in high frequency motor. 11 is 180° from the center
The grinding wheel shaft 11 is a long shaft, and the grinding wheel shaft 10 is provided separately.
is attached with a short shaft. Furthermore, a measuring device 12 is attached to the turret grindstone head 9 at a position of 90'' with respect to the grindstone axis, and a cutting tool 13 for turning is attached to the opposite side thereof.

The measuring device 12 has an L-shaped filler 12a at the tip of the detection shaft.
is fixed and can detect displacement values in three directions: the negative side in the pushing direction, the positive side in the direction perpendicular to the detection axis, and the negative side, and uses an electric micrometer that emits an output signal at the 0 point. However, for the type of measurement, a touch sensor can also be used, and a commercially available one can be used.

It is of course possible to selectively attach to the turret grinding wheel head a lifting shaft, a honing shaft, a machining tool, etc. other than those mentioned above, and the control axes are not limited to the X axis and the Z axis.

The rough-machined workpiece W attached to the chuck 5 is rotated and indexed to the machining position by the cutting tool 13 if necessary, and the main shaft is switched to rotation for cutting.The table 6 is rotated on the Z axis and the turret grindstone head 9 is rotated on the X axis.
Axis control is used to cut the outer diameter, inner diameter, or end face.

After the installation error is corrected, the turret grindstone head 9 is indexed, the grindstone shaft 10 is set at the processing position, and the headstock 3 is set at the outer diameter grinding position by operating the fluid pressure cylinder device 4, and the end face and outer diameter of the workpiece are ground. After processing, the turret grindstone head 9 is
The headstock 3 is actuated by operating the fluid pressure cylinder device 4, which rotates the grindstone shaft 11 to the machining position by controlling the shaft and turning it to the retreat position.
is set as the internal grinding position, and the turret grindstone head 9 is controlled along the X-Z axes to perform internal grinding.

Next, in order to measure the machining accuracy of the workpiece on the machine, the turret grindstone head 9 is retracted and rotated under X-Z axis control, and the measuring instrument 12 is indexed to the measurement position.

In addition, a reference ring with a known inner diameter and thickness is attached to the center of the chuck 5, and the offset value of the measuring instrument is determined by abutting the fin 12a in the Z-axis direction with the end face position of the reference ring (distance from the machine origin) known. Calculate and find. Furthermore, the measuring device 12 measures in advance a correction amount (grabbing amount) α due to switching of the measurement direction when measuring the inner diameter and a correction amount β due to switching of the measurement direction when measuring the outer diameter.

a. Inner diameter measurement (Fig. 3) Control the turret grindstone head 9 on the X axis to bring the tip side surface of the grinder 12a into contact with the inner diameter of the workpiece W, and measure the X axis position when outputting the 0 point body number with Xl, the measuring instrument. 18 of the inner diameter by moving it in the opposite direction.
On the opposite side of 09, bring the fish into contact from the opposite direction, and let the X-axis position when the 0-fish signal is output be X, and calculate XI Xy) + α = inner diameter using the NC device.

b. Outside diameter measurement (Fig. 4) Control the measuring instrument on the X and Z axes to bring the tip side surface of the fissure 12a into contact with the outside diameter of the workpiece from the X-axis direction, and measure the X-axis position when outputting the 0-point body symbol. Xl, then move the X-Z axis 1ilI m and bring the fish 12a into contact with the outside diameter from the opposite side, and set the X-axis position to Xt when the 0 fish signal is output.XI
-Xl)-β=outer diameter is calculated by the NC device.

C8 end face step and end face measurement (Fig. 5) Control the measuring instrument 12 along the Z-X axis to bring the tip of the fibre 12a into contact with the outer end from the axial direction, and measure the two-axis position when outputting the θ point signal.
+, then contact the fish 12a with one stride, set the X-axis position at the time of outputting the θ point signal to Z2, and calculate Z+ ZZ one step difference using the NC device.

In addition, the workpiece is held in contact with the axial reference surface of the chuck, and the tip of the fissure 12a is brought into contact with the end surface from the axial direction, and the machining allowance of the workpiece is determined from the X-axis position when the O point signal is output and the reference surface position. Calculate and correct the Canadian program. Furthermore, when gripping the workpiece without contacting it with the reference surface position of the chuck, the fissure 12a is brought into contact with the end face in the same way, and the deviation amount between the X-axis position and the target value when the 0 fish signal is output is calculated to determine the machining origin. to correct.

d. Roundness measurement (Fig. 6) Control the measuring instrument 12 along the Z-X axis to bring the fin 12a into contact with the inner diameter (or outer diameter), rotate the main shaft and the workpiece, and measure the measuring instrument 1.
Measure the maximum value and minimum value of the output of 2.Xmax -Xm1
n)/2=The roundness is calculated by an NC device and displayed as a radius. Note that the touch sensor cannot be used in this case.

e. Measurement of end face runout (Figure 7) Control the measuring instrument 12 along the X-Z axes to bring the tip of the fiber 12a into contact with the end face and rotate the main shaft to measure Z Ilax-Zmi
n=runout is calculated by the NC device. In this case, the touch sensor cannot be used.

f1 cylindricity measurement (Fig. 8) The measuring device 12 is controlled on the Z-X axis to bring the fissure 12a into contact with the inner diameter (or outer diameter) near the end face of the workpiece at a predetermined position on the X-axis from the X-axis direction, and output The signal value is determined by retracting the X-fiber 12a on the X-axis, positioning it at a predetermined position on the Z-axis, positioning it at the predetermined position on the X-axis, bringing the fiber 12a into contact, and assuming the output at that time to be X□ (XI Xz )/2-Cylinder The degree or taper amount is calculated by an NC device and displayed as a radius. In this case, measurement can be performed using a touch sensor if the current position of the turret grindstone head is i* recognized.

g. Inner diameter level difference measurement (Fig. 9) Control the measuring instrument 12 along the Z-X axis to measure the inner diameter of the large diameter.
Let a be the X-axis position when the contact O-point signal is outputted as X, and then set the fish 12a on the inner diameter of the small diameter as the X-axis position when the contact zero-fish signal is outputted as X, and calculate XI Xz=step by the NC device.

h, Outer diameter step measurement (Figure 10) Control the measuring instrument 12 on the Z-X axis to bring the fish 12a into contact with the large outer diameter, and set the X-axis position when the 0 fish signal is output to X1, where it touches the small outer diameter at the θ point. Assuming that the X-axis position at the time of signal output is X, the one step difference between X and -X is calculated by an NC device.

i. Measuring inner and outer diameters using a mask Attach a mask with known inner and outer diameter dimensions concentrically with the main shaft, or position it concentrically with the main shaft using a mask transport device when necessary. First, the inner or outer diameter of the mask in this state is measured and calculated using a measuring instrument. Calculate the difference between this measured value d0 and the actual mask dimension d, and use it as a correction value (cutting amount). Next, calculate the inner or outer diameter of the workpiece as described above, and use this value as the correction value. The correction value is added by the NC device for the inner diameter, and subtracted for the outer diameter.

” Measuring the position of the cutting edge of the diamond repair tool (Fig. 11) Diamond repair tool 1 is attached to one arm of the cross-shaped fin 12a.
A measuring element made of a high hardness material and having a contact surface 12X in the X-axis direction and a contact surface 122 in the Z-axis direction that contacts the tip of the cutting edge of No. 4 is added so as to be at the center height of the diamond repair tool. The other two arm probes are used for the above-mentioned measurements.

The measuring device is controlled along the X-Z axes to the measuring position, and the contact surface 12X of the fish 12a is brought into contact with the fish 12a from the X-axis direction, and the X-axis position X1 when the 0-fish signal is output is stored in the NC device. Next, the contact surface 12z of the fissure 12a is brought into contact from the Z-axis direction, and the Z-axis position Z at the time of outputting the O point signal is stored in the NC device. Then, offset values of the X-axis and Z-axis of the diamond correction tool are calculated.

k. Measuring the position of the grinding wheel The approximate dimensions are measured in advance, and the data is input as NC data. The grinding wheel is controlled along the X-Z axes to position it in front of the grinding position on the inner diameter of the workpiece, and the grinding wheel is ground to the X- and Z-axis command dimensions. Next, replace the grindstone with a measuring instrument and control the X-Z axis to measure the inner diameter and length of the workpiece, and calculate the X value when the zero fish signal is output.
- Store the Z-axis current value in the NC device, calculate the grindstone offset based on the difference with the command value, and set the grindstone origin.

In addition, it is possible to measure inner and outer diameter runout, end face groove measurement, inner diameter groove measurement, and outer diameter groove measurement, and various origin settings are also possible. These measurements are appropriately performed before and after machining as necessary.

Effects Since the structure is as described above, the present invention has the following effects.

Since the grinding machine of claim 1 is equipped with a cutting tool, it is possible to remove the eccentricity mounting error when mounting the workpiece, and it is possible to shorten the grinding time by minimizing the grinding allowance, thereby increasing the grinding efficiency. can be improved. Furthermore, since the headstock can be positioned at the inner diameter position and the outer diameter position, the position control distance of the turret tool rest is shortened, and idle time can be reduced.

The in-machine measurement method according to claim 2 is performed using one measuring instrument, so there is no need to prepare a measuring instrument suitable for the type of measurement (it can reduce costs, and there is no need to replace the measuring instrument or remove the workpiece). There is no need for a long measurement preparation time, which is required when taking measurements at other locations, making it possible to significantly shorten the time, and since the measurement is carried out on-board, high measurement accuracy can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is a front view of the grinding machine of the present invention, FIG. 2 is a plan view of the turret grindstone head, and FIGS. 3 to 11 are diagrams showing various measurement states. 3... Headstock 4... Fluid pressure cylinder device 6... Table 9... Turret grinding wheel head 10.11... Grinding wheel spindle 12
...Measuring instrument 13...Bite 3 Figure 11 Figure 2a

Claims (2)

[Claims] (1) A headstock that is positioned in the X-axis direction at an inner grinding position and an outer grinding position, and a table that is moved and positioned in the Z-axis direction,
The turret grindstone head is movable and positioned in the X-axis direction on the table, and the turret grindstone head is equipped with a grindstone shaft, a cutting tool, etc., and a measuring device at the turret index position, and is used for grinding, cutting, and measurement. An NC grinding machine characterized by being able to. (2) A single measuring instrument installed in the grinding machine body measures the inner diameter, outer diameter, end face step, roundness, end face runout, cylindricity, inner diameter step, machining allowance, diamond correction tool position, etc. of the workpiece.
An in-machine measurement method for a grinding machine characterized by being able to measure the dimensions of a grindstone, etc.