JPH0692060B2 - Correction method for misalignment of Y-axis in the turret tool post - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a center displacement of a turret of an NC lathe in the Y-axis direction that enables machining of a position displaced in the Y-axis direction by a rotary tool by indexing a turret tool post at an arbitrary angle. Regarding the correction method.

2. Description of the Related Art In a conventional NC lathe, drilling with a drill, grooving with an end mill, and chamfering can only be performed toward the axis of the workpiece. In order to perform machining that does not face the center of the axis, a headstock provided with a headstock that is movable in the Y-axis direction or a Y-axis moving device having a tool mount is commercially available. However, this device has a problem that the device becomes large-scale and the price becomes high.

For this reason, NC lathes have emerged that allow Y-axis machining with little price increase. In this NC lathe, for example, as shown in FIGS. 1 and 2, in a known lathe, a turret tool post 2 on a middle table 1 is supported so that a turret 3 can be indexed according to the number of tools to be attached. The turret tool post 2 is capable of rotating and positioning the turret axis within the range of 90 ° in the X-axis direction and the Z-axis direction. As shown in FIG. 2, the turret 3 is provided with a curvic coupling 4 having teeth on the turret side which are multiples of the turret indexing number on the surface facing the turret 2.
On the side, a carbic coupling 5 having the same number of teeth as the carbic coupling 4 and having teeth concentrically arranged inside is mounted. A carbic coupling 8 for clamping which is engaged with the carbic couplings 4 and 5 is fixed to the piston rod of the piston 7 fitted in the cylinder 6 at the center of the tool rest 2. An external gear 9 is engraved on the outer circumference of the curvic coupling 4 of the turret 3, and the external gear 9 has a turning motor 10 provided on the tool rest 2.
The gear 11 of the gear group connected to the output tooth of the gear meshes.
Further, the turret 3 is rotatably supported with a tool shaft 12 at the tip of which a rotary tool T is fitted at at least one position where the turret 3 is attached. The tool shaft is located eccentrically from the turret rotation shaft. The tool shaft 12 is rotated via a gear group 15 from a turret central shaft 14 rotated by a tool motor 13 provided on the tool rest 2. The tool shaft 12 can be rotated at any angular position of the turret 3 if necessary.

In this turret turret 2, in order to process with the rotary tool T at a position in the Y-axis direction a from the outer periphery of the cylindrical portion of the workpiece W, the pressure fluid is sent to the cylinder 6 to effect the carbic coupling 8
Move to disengage. In order to set the rotary tool at the machining position to have a core height a from the X axis, the turret turning angle is calculated in the control device, the turning motor 10 is driven, and the turret is stopped turning by a predetermined angle. When this turning angle is not at the indexing position of the curvic coupling, leave the clamping curbic coupling in place and use the tool rotation motor.
13 is driven to rotate the rotary tool T for processing.

In this way, when the rotary tool is used to control the turning angle of the turret to machine the outer peripheral position of the workpiece that is offset from the center of the spindle in the Y-axis direction, the assembly accuracy of the machine itself, such as eccentricity error and thermal expansion, affects the Y-axis However, there is a problem in that the processing origin of (1) moves and stable processing accuracy cannot be obtained. And for the correction of the machining origin, the machined workpiece was removed, the measurement was performed outside the machine using a three-dimensional measuring instrument, and the correction was made based on the result, which was inefficient and required extra work time.

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 stabilize the processing accuracy when the turret is stopped by the turning control to perform the processing in the Y-axis direction. It is what

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention provides a spindle that can be rotationally indexed, a turret that can move in the X-axis and the Z-axis, and an eccentric position parallel to the turning axis of the turret. In an NC lathe that consists of a rotary tool shaft provided and the Y-axis function is made possible by the rotary index of the turret and the axis orthogonal to the axis of the rotary tool shaft, the rotary tool of the turret is used to center the workpiece end face. A hole is drilled, the Y-axis direction of the workpiece is swung 90 ° in the X-axis direction, and a X-axis direction touch sensor is used to output a touch signal in the + -2 direction passing through the swivel center. The positions of both ends of the hole diameter are measured, and the displacement amount with respect to the machining origin is obtained from the hole center position obtained from this measured value, and this value is taken as the Y-axis origin displacement amount.

An embodiment will be described with reference to FIGS. 1 to 4. On the tool mounting surface of the turret 3, at least + -2 in the direction passing through the center of the turret.
A touch sensor 23 that outputs a touch signal in one direction and outputs the same signal in both directions is mounted. The spindle 21 supported by the spindle stock 20 and fitted with the chuck 22 at the tip has a known structure capable of C-axis indexing at an arbitrary angle.

In order to correct the error in the Y-axis direction of the turret 3 of the tool rest 2, the rotary tool T is indexed and clamped at the regular machining position (turret indexing position), and a hole is drilled in the center of the end face axis of the workpiece W. To do. The main shaft 21 is indexed to the C axis and turned 90 degrees toward the tool post 3 side so that the Y axis position is aligned with the X axis direction. The rotary tool T is changed to the touch sensor 23 and indexed and clamped at the processing position. First, the touch sensor 23 is brought into contact with the inner diameter end of the hole Wa in the + X axis direction by controlling the tool rest 3 on the X axis. With this contact signal
The NC unit reads the X-axis position A from the origin 01. Then, the tool rest 3 is controlled to move in the -X axis direction to bring the touch sensor 23 into contact with the inner diameter end opposite to the hole Wa. NC with this contact signal
The device reads the X-axis position B from the origin 01. The NC device calculates the origin offset amount y from the origin 01 by calculation A- (A + B) / 2, and the position 02 offset by the y amount in the Y-axis direction is Y.
It is used as a new machining origin in the axial direction.

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

A touch sensor or measuring instrument that can provide contact signals in the + -2 direction on the tool post without the need for a special measuring device
By using the NC function, misalignment correction in the Y-axis direction can be easily performed while the workpiece is mounted on the machine without providing a large Y-axis moving means, suppressing the increase in price and stabilizing the processing accuracy. Can be measured.

[Brief description of drawings]

1 is an explanatory front view of a lathe, FIG. 2 is an explanatory view showing a turret of a tool rest, a clamp mechanism and a drive system for rotating a tool shaft and a turret, and FIG. 3 is a view showing a tool rest position at the time of drilling,
Fig. 4 is a slant bed lathe measurement diagram, and Fig. 5 is the first diagram.
It is an AA view of the figure. 2 ... Turret tool post, 3 ... Turret 21 ... Spindle, 23 ... Touch sensor T ... Rotating tool, W ... Workpiece

Claims (1)

[Claims] 1. A turret comprising: a rotary indexable main shaft; a turret movable in the X-axis and Z-axis; and a rotary tool shaft provided in parallel with an eccentric position with respect to the turning axis of the turret. In an NC lathe capable of Y-axis function by the rotary indexing and the axis orthogonal to the axis of the rotary tool axis, a rotary tool of the turret drills a hole in the center of the end surface of the workpiece, and the Y-axis direction of the workpiece is 90 degrees. Rotate in the X-axis direction, measure both ends of the hole diameter in the X-axis direction using a measuring device provided on the tool post that outputs a touch signal in the + -2 direction that passes through the center of rotation, and obtain from this measurement value. A method for correcting the misalignment of the turret tool post in the Y-axis direction, wherein the amount of displacement with respect to the machining origin is obtained from the hole center position and this value is used as the Y-axis origin displacement.