JPS6111728B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a position correction method for adjusting and correcting the position of a cutting edge of a boring tool attached to a main shaft of a machining center.

When automatically correcting the position of the cutting edge of a boring tool attached to the main spindle of a machining center, conventionally a rod that moves in the axial direction was installed in the main spindle.
A pin inclined with respect to the axis was attached to the tip of this rod, while an inclined groove was provided in the tool shank to engage the pin, and by moving the rod in the axial direction, the tool was moved in the radial direction. . Alternatively, a rotatable rod is provided within the main shaft, an eccentric gripping section is attached to the tip of the rod, and the tool shank is gripped by the gripping section, and the rod is rotated to move the tool in the radial direction. However, all of these conventional devices incorporate drive mechanisms such as rods into the main shaft and require a drive source for these drive mechanisms. As a result, the structure becomes complicated, and a control section for controlling the drive source is also required, resulting in an expensive machine as a whole. In addition, as in Japanese Utility Model Publication No. 49-5781, a cylinder provided on the saddle has a sliding piece protruding from the side surface that operates a pawl that drives a ratchet wheel that is integrated with a shaft that has an eccentric cam that flexes a flexible cutting tool. It is known that a sliding piece is moved by the action of a piston. This requires a special cylinder device as a driving source, which increases costs.

In the present invention, a boring tool is mounted on a normal spindle, and the spindle head, table, and saddle are appropriately moved relative to each other according to commands from a numerical control device. Rotary motion or linear motion is transmitted to the correction input end of the correction mechanism to drive the correction mechanism to correct the position of the cutting edge.

Next, embodiments of the present invention will be described based on the drawings. A column 2 is erected at one end of the upper surface of a bed 1 of a machining center. A spindle head 4 is mounted so as to be movable up and down along a vertical guide map (not shown) of the column 2 by a first electric motor 3 provided on the upper surface of the column 2. A spindle 5 is supported horizontally on the spindle head 4, and a boring tool 6 is attached to the tip of the spindle 5. Further, a saddle 8 is placed on the upper longitudinal horizontal guide surface 7 of the bed 1.
It is moved by a second electric motor 9 attached to the right end of the bed. A table 11 is placed on a guide surface 10 on the upper surface of the saddle 8 and perpendicular to the longitudinal horizontal guide surface 7, and is moved by a third electric motor 12 attached to the end surface of the saddle 8. A protruding portion 13 that is engaged with the boring tool 6 is attached to one corner of the upper surface of the table 11. The first, second, and third electric motors 3, 9, and 12 are rotated by commands from a numerical control device 14.

Next, the cutting edge position correction mechanism installed in the boring tool will be explained. The front end surface of the main body 15 of the boring tool 6 is provided with a guiding dovetail groove 1 in a direction perpendicular to the tool axis.
6 is formed. A tip holder 17 is attached so as to be movable along this dovetail groove 16, and a tip 18 is fastened to the tip of the tip holder 17. A nut 1 is attached to the rear end surface of the tip holder 17.
9 is attached and is threadedly engaged with a screw shaft 20 that is supported within the main body 15 in parallel to the dovetail groove 16. A screw gear 21 is formed at one end of the screw shaft 20, and a gear shaft 23 having a screw gear 22 that meshes with the screw gear 21 is perpendicular to the tool axis and is connected to the screw shaft 2.
It is journalled within the body 15 at right angles to 0. A pawl 25 is bored at least in one place on the circumference 24 of one end of the gear shaft 23, and this pawl 25 follows a reference line carved on the outer surface of the bearing holder 26 as shown in FIG. This is the one that is set first, matching the position of 27. The protrusion 18 includes a bracket 28 attached to one corner of the upper surface of the table 11, a cylinder 29 fixed to the bracket 28, a piston 30 fitted into the cylinder, and the cylinder 2.
It consists of a piston rod 31 projecting upward from the piston rod 9.

Next, the effect will be explained. Claw 25 and reference line 2
Assuming that the boring tool 6 matching the position 7 is attached to the tip of the spindle 5, the spindle 5 is stopped at a constant angle position with the pawl 25 facing downward. The spindle head 4, table 11, and saddle 8 are moved to stop the piston rod 31 at a position directly below the point A position on the circumference 24 where the tip of the piston rod 31 can horizontally abut against the pawl 25. Thereafter, the second electric motor 9 and the third electric motor 12 are
by simultaneously operating the saddle 8 and the table 11, giving a combined motion to the piston rod 31, causing the piston rod 31 to move around the circumference 2 shown in FIG.
Draw the same circular locus as in step 4 in the direction of the arrow. Due to this circular movement of the piston rod 31 in the horizontal plane, the side surface of the piston rod 31 comes into contact with the side surface of the pawl 25, thereby rotating the gear shaft 28. The rotation of the gear shaft 23 is transmitted to the screw shaft 20 through the two meshing screw gears 21 and 22, and causes the tip holder 17 to move together with the nut 19. As a result, the tip position of the tip 18 is corrected.

Since the relationship between the rotation angle of the gear shaft 23 and the correction movement distance of the tip tip is known, it is sufficient to give the piston rod 31 a rotation angle corresponding to the required correction distance of the cutting edge. The stop position of the piston rod 31 and the stop angle position of the pawl 25 after the first correction are stored in the numerical control device 14, and serve as a reference for calculating the rotation angle of the piston rod 31 due to the circular motion during the second correction.

6 and 7 are views showing other embodiments, in which a tapered hole 33 is bored in the center of the tool body to which a cutting tool 32 is attached, forming a hollow cylindrical shape 34, and extending in the circumferential direction. Slots 35 are made at equal intervals and at a predetermined depth. A tapered rod 36 having the same taper ratio is inserted into the tapered hole 33 so as to be slidable in the axial direction, so that the diameter of the hollow cylindrical portion 34 can be expanded. At the rear of the tapered rod 36 is a male threaded portion 3.
7 is formed, and the rearmost end of the tapered rod 36 is keyed to a support 38 mounted in the shank of the boring tool to prevent rotation. A nut member 39 is screwed into the male threaded portion 37 while being prevented from moving in the axial direction.
The outer periphery of the nut member 39 is provided with teeth of a ratchet wheel. A slide bar 41 having a pawl 40 that engages with the teeth of the ratchet so as to rotate the ratchet is mounted within the tool body so as to be slidable in a direction perpendicular to the axis of the boring tool. This slide bar 41 is always urged outward by a spring 42, and its outer end protrudes from the main body. bar 4
A spring 43 is attached to the inner end of 1 to press the pawl 40 against the teeth of the ratchet wheel. Furthermore, slide bar 41
A pin 44 is attached to prevent it from falling off from the main body. Further, a pawl 45 is attached to the main body, which always engages with the teeth of the ratchet wheel in order to prevent the ratchet wheel from reversing.

Next, the function of this product will be explained. The spindle is stopped at a certain angle position, the slide bar 41 is directed downward, the axes of the bar 41 and the piston rod 31 are aligned, and the spindle head 4 is reciprocated toward the table 11 according to a command from the numerical controller 14. . The slide bar 41 hits the piston rod 31 and is pushed in, and the pawl 40 turns a nut 39 with a ratchet wheel. Since the taper rod 36 screwed into the nut 39 is prevented from rotating, it retreats in the axial direction and the cylindrical portion 34
Open the tool and the cutting edge position is corrected.

As described above, in the present invention, no drive mechanism for correcting the cutting edge position is provided in the main spindle, and the correction mechanism is provided only in the boring tool, so that a normal main spindle can be used. Since the main body function is used as the drive source for the correction mechanism for the composite movement of the saddle and table or the linear movement of the spindle head, the overall configuration of the machine is simple. Just by feeding the numerical control device with a program for correcting the cutting edge position, it can be automatically performed. The cutting edge position can be corrected.

In addition, in the above explanation, there is a method in which the table is moved synthetically with the saddle in a horizontal plane, the piston rod is made to draw a circular trajectory, and the rotational motion is transmitted to the correction input end of the correction mechanism in the boring tool, or the spindle head is moved relative to the table. We have described a method of transmitting linear motion to the compensation input end of the compensation mechanism in the boring tool by moving the machine in a straight line, but it is also possible to perform rotational motion using the saddle and the spindle head, and it is also possible to perform linear motion using the table as a means of transmitting linear motion. It is also possible to move. Alternatively, a simple pin circle may be installed in place of the piston cylinder device placed on the table, or an engagement hole may be drilled in the top surface of the table and the claw 25 may be fitted into this hole.

[Brief explanation of the drawing]

Figure 1 is a schematic external view of the machining center, Figure 2
The figure is a partial cross-sectional view of the boring tool, Figure 3 is a partial cross-sectional view of the boring tool showing how the gear shaft is attached, Figure 4 is a - perspective view of Figure 3, and Figure 5 is a protruding part. FIG. 6 is a cross-sectional view of a boring tool showing another embodiment, and FIG. 7 is a cross-sectional view of FIG. 6. 4... Spindle head, 5... Spindle, 6... Boring tool, 11... Table, 14... Numerical control device.

Claims (1)

[Scope of Claims] 1. A spindle with a boring tool equipped at its tip equipped with a cutting edge position correction mechanism with a correction input end provided on the side surface is stopped at a fixed angle position within the spindle head, and the correction input end is connected to a table. The correction input end and the protrusion are brought into a state in which they can be engaged with the protrusion provided above, and the spindle head, the table, and the saddle are appropriately moved relative to each other in response to a command from a numerical control device. automatic correction of the cutting edge position of a boring tool, characterized in that the cutting edge position of the boring tool is automatically corrected by engaging the two and further transmitting a motion serving as a correction input to the correction input end by the movement thereof. Method. 2 The saddle and the table are caused to move relative to each other, and the resulting movement transmits rotational motion to the correction input end of the cutting edge position correction mechanism in the boring tool. Automatic correction method for cutting edge position of boring tools. 3. A boring tool according to claim 1, characterized in that the spindle head and the table are moved relative to each other, and the linear motion is transmitted to the correction input end of the cutting edge position correction mechanism in the boring tool. Automatic blade edge position correction method.