JPS6210777B2 - - Google Patents

Description

[Detailed description of the invention] In numerically controlled metal machine tools, it is necessary to accurately position the cutting edge at a constant position. Optical or electrical settings are made at . That is, a method is used in which a numerical control device finds the desired position of the cutting edge in the coordinate direction, and if there is a discrepancy with the index point, the tool wear correction function corrects the cutting edge position to the correct position.

To determine the position of the cutting edge, the position in the perpendicular direction is generally set as a planar coordinate system, but if setting devices are provided independently for each of the two directions, the space will become large and the function of the machine tool may be affected. Moreover, it is an expensive device.

Conventionally, in lathes, etc., highly accurate setting of the cutting edge position is often done only in the diametrical direction of the workpiece, but in order to position the cutting edge with high accuracy in the longitudinal direction of the workpiece, it is necessary to set the cutting edge position in the longitudinal direction of the workpiece at the correct position. It is necessary to measure the diameter and the perpendicular position.

The object of this invention is to measure the position of the cutting edge in two perpendicular directions using a single highly accurate switch.

In this invention, the blade edge position measuring element is arranged perpendicularly to two axes of a numerical control device, such as the X-axis and Z-axis of a lathe, one of which is engaged with a high-sensitivity switch via a lever, and the other is engaged with a high-sensitivity switch via a lever. engages with another probe to operate a high-sensitivity switch, and compares it with the position indicated by the numerical control device.

Embodiments of lathes will be described below with reference to the drawings. FIG. 1 is a schematic front view of a numerically controlled lathe. Above the machine base 1 is a headstock 2 facing oppositely.
A tailstock 3 is provided, and a sliding surface 4 is fixed to the back of the machine base 1 in parallel with the spindle centerline. The headstock 2 is fixed to the sliding surface 4, and the tailstock 3
is fixed and movable. A slide 5 that moves parallel to the spindle center line slides into the sliding surface 4,
A sliding surface is provided orthogonally to the slide 5, and a cross slide 6 slides therein. A tool post 7 is attached to the cross slide 6. Although not shown, a feeding device for feeding the slide 5 and the cross slide 6 is provided. The tool rest 7 is a turret tool rest that rotates and indexes around an axis parallel to the plane of the paper, but may also be of the type that rotates and indexes on an axis that intersects the plane of the paper.
A cutting tool 8 is fixed to the tool rest 7.

The tailstock 3 is equipped with a blade edge position setting device 9 according to the present invention.

The drawings show an embodiment of the blade edge position setting device 9, in which FIG. 2 is a front view, FIG. 3 is a plan view, FIG. 4 is a sectional view taken along line A-A in FIG. 3, and FIG. -B sectional view, and FIG. 6 is a CC sectional view of FIG. 3. In the embodiment of the present invention, the blade edge positions are provided along the X axis (in the radial direction with respect to the spindle center line) and the Z axis (in the direction of the spindle center line). A high-sensitivity switch (trade name: Touch Switch) 11 has a bolt 12 attached to the body of the tailstock 3.
It is attached to a bracket 15 which is fixed by bolts 14 to a base 13 which is fixed by. The bracket 15 has a frame structure, and a high-sensitivity switch 1 is installed in a hole in a horizontal member extending between a pair of side plates.
1 is inserted, and the horizontal member is clamped and fixed by nuts 16 and 17. The coaxial cable 18 of the high sensitivity switch 11 is connected to the bracket 15.
The other end is connected to a numerical control device.

As shown in FIG. 6, the X-axis measuring table 20 has a pair of miniature bearings 2 on both sides of a horizontally bored hole.
4 is inserted into the bracket 15 with a spacer 24A in between, and the ball seat 21 is press-fitted and fixed to the bracket 15 via the ball 26.
and is in contact with the spherical seat 22 screwed into the female thread of the bracket 15. The ball seat 22 is fixed with machine screws 23. Therefore, the X-axis measuring stand 20 is pivotally mounted to the bracket 15 at a pivot point 25 (FIG. 4).

A Z-shaped arm 29 is positioned on the X-axis measuring table 20 with a pin 27 and fixed with a bolt 28. At the tip of the arm 29, a pin 30 is adapted to come into contact with a measuring element which is resiliently repelled in the axial direction of the high-sensitivity switch 11 into which a pin 30 is press-fitted. Therefore, the arm 29 can rotate around the pivot point 25 of the X-axis measuring table 20.

A horizontal member is passed between the side plates on the upper surface of the bracket 15, two internal threads are cut in the horizontal member, adjustment screws 31 and 32 are screwed into the horizontal member, and the lock nut 3 is screwed into the horizontal member.
3 and 34 respectively after adjustment. The adjusting screw 32 is loosely fitted into a hole drilled in the arm 29 from below, so that the stepped portion of the screw head can come into contact with the edge of the hole. The arm 29 is adjusted by adjusting the distance between the tip of the adjusting screw 31 and the step of the head of the adjusting screw 32.
is restricted in its movement.

An X-axis measuring element 35 in the X-axis direction is fixed to the upper surface of the X-axis measuring table 20 on the opposite side to which the arm 29 is fixed. The X-axis probe 35 is made of a hard material such as cemented carbide metal. The distance between the pin 30 and the pivot point 25 and the distance between the X-axis probe 35 and the pivot point 25 are selected to have a sufficiently large ratio.

To summarize the above, the X-axis measuring table 20 and the arm 29
The first lever is integrally connected to the pivot point 25 and has a measuring surface at one end, and the other end has a lever magnification ratio to push a high-sensitivity switch.

A horizontal member 15A is fixed to the extending ends of the pair of side plates of the bracket 15 with bolts 36.
A bushing 37 is press-fitted into the horizontal member 15A, a pin 38 is precisely slid into the bushing 37, and the pin 38 is inserted into the bushing 37 with precision.
A Z-axis measurement stand 40 in the Z-axis direction is fitted into the other end of the 8, and is fixed with machine screws 41.

The Z-axis measuring table 40 is partially made of channel steel, and its web center portion is pivoted by a pin 38, machine screws 39 are screwed vertically into both sides, and an Z having a measuring surface perpendicular to the measuring surface of the axis measuring element 35 and parallel to the pin 38
A machine screw 43 into which an axis measuring element 42 is press-fitted is screwed. The tip of the X-axis measuring table 20 is lowered one step, so that the tip of the Z-axis measuring table 40 covers it. The tip of the machine screw 39 is in contact with the X-axis measuring table 20. Reference numeral 44 denotes a machine screw for fixing the machine screw 43 after adjustment.

To summarize the configuration of the Z-axis measuring table 40 part described above, the second lever is connected to a pin 38 that is perpendicular to the axis of the first lever consisting of the X-axis measuring table 20 and the arm 29 and parallel to the measuring surface of the first lever. Eggplant Z-axis measuring stand 40
is pivotally mounted, and the Z-axis measuring stand 40 can press an end with a measurement surface of the first lever, and can press a measurement surface in a direction perpendicular to the measurement surface of the first lever and parallel to the pin 38 at the end. It is set up in

Before setting the blade edge position, press the high sensitivity switch 1.
The measuring element No. 1 resiliently contacts the pin 30 near the protruding end, and the adjusting screw 31 and the arm 29 are separated from each other. The arm 29 and the head of the adjusting screw 32 are in contact with each other. At the above positions of the X-axis measuring table 20, the two machine screws 39 come into contact with the X-axis measuring table 20, and the Z-axis measuring table 4
0 remains horizontal.

Move the slide 5 to position the tip of the cutting tool 8 directly above the X-axis measuring element 35, then move the cross slide 6 toward the X-axis measuring element 35 and push the cutting edge of the cutting tool 8 into the X-axis measuring element 35. When hit, the X-axis measurement stand 20
rotates counterclockwise in FIG. 4 about pivot point 25, arm 29 rotates in the same manner, and pin 30 pushes high-sensitivity switch 11 into operation. Since the lever ratio is large, not only the operating distance of the high-sensitivity switch 11 is small, but also minute displacements of the X-axis probe 35 can be detected. The sensitivity of the high-sensitivity switch 11 and the position of the cross slide 6 are compared, and the difference is used to adjust the cutting edge of the cutting tool 8 to bring it to an accurate position. Alternatively, the tool wear correction function automatically moves and adjusts the tool to an accurate position relative to the origin position. As described above, the position of the cutting edge of the cutting tool 8 in the X-axis direction is adjusted. To adjust the position of the cutting edge of the cutting tool 8 in the Z-axis direction, after adjusting the cutting edge position of the cutting tool 8 in the guess. Which side of the Z-axis probe 42 should be brought into contact is determined by the hand of the side cutting edge of the cutting tool 8. Now, in Fig. 5, tool 8 is attached to the Z-axis probe 42 on the left side.
When the side cutting blade is applied, the Z-axis measuring table 40 is supported by the pin 38 via the adjustment screw 43, the pin 38 rotates in the bush 37, and the Z-axis measuring table 40 is tilted downward to the left, X-axis measuring stand 2 via machine screw 39
Hold down 0. The displacement of the X-axis measuring table 20 operates the high sensitivity switch 11. The position and the position of the slide 5 on the Z axis are compared, and the cutting edge of the bide 8 is moved in the Z axis direction by the difference, or the tool wear correction function is automatically adjusted to the origin position. In numerically controlled machine tools, the above-mentioned adjustment of the cutting edge position of the cutting tool is carried out each time after replacing the tip of the cutting edge of the tool, and in other cases, it is carried out according to the number of workpieces cut while taking into account the wear of the cutting edge. Further, the above operations for setting the blade edge position are performed fully automatically.

Although the above explanation has been about the cutting tool of a lathe, it is not limited to lathes, and the position of the cutting edge of the cutting tool can also be set using the X-axis feeler 35 and the Z-axis feeler 4.
2 can be replaced with the position setting of the cutting edge in the radial cutting direction and the feeding direction, and can also be replaced with the position setting of the cutting edge in the cutting edge feeding direction and the radial cutting direction. Of course, in this case, the Z-axis measuring stylus 42 of the Z-axis measuring table 40 must be provided on only one side, and one side must be deleted. Since the attachment to the tailstock 3 is at a position rotated by 90 degrees, it is necessary to change the arrangement of the high-sensitivity switch 11 and change the shape of the bracket 15.

As described above, according to the blade edge position setting device of the present invention, the blade edge position in two orthogonal directions can be detected using a single high-sensitivity switch. Therefore, the position of the cutting edge in the longitudinal direction of the workpiece can be set with the same high precision as in the diametrical direction, and is still economical.

There are very few pivot points for the members that magnify or transmit the measured displacement, and with respect to the X axis, the first lever, Z
Regarding the shaft, since a second lever is provided that interlocks the first lever, the pivot point 25 of the first lever can be supported with high accuracy for the X-axis, and the pivot point 25 of the second lever can be supported for the Z-axis. Since it is only necessary to have high accuracy, it is easy to manufacture the device of the present invention, and the processing accuracy and assembly accuracy can be made good, and errors do not accumulate regarding the X-axis, and cumulative errors regarding the Z-axis are extremely small. The embodiment is shaped along the side of the tailstock, occupies a small space, and does not affect operability or other functions.

[Brief explanation of the drawing]

Fig. 1 is a front view schematically showing a lathe, Fig. 2 and the following show examples, Fig. 2 is a front view, Fig. 3 is a plan view, and Fig. 4 is a sectional view taken along line A-A in Fig. 3. , FIG. 5 is a sectional view taken along line BB in FIG. 3, and FIG. 6 is taken along line C-- in FIG. 3.
It is a sectional view of C. 11...High sensitivity switch, 20...Measurement stand, 2
9...Arm, 35...Measuring head, 38...Pin,
39... Machine screw, 40... Measuring table, 42... Measuring head, 43... Machine screw.

Claims (1)

[Claims] 1 The X-axis feeler, which contacts the tip of the cutting edge of the cutting tool and is displaced in the cutting direction of the tool, is fixed at one end, the middle part is pivoted, and the other end is a switch with a lever ratio that expands the movement of the X-axis feeler. a second lever pivoted on a pin perpendicular to the pivot axis of the first lever and parallel to the measuring surface of the X-axis measuring element of the first lever; The second lever end presses the first lever at the end of the first lever on the side where the X-axis measuring element is located, and contacts the first lever so that the switch at the other end of the first lever can be operated. A second lever is pivoted to the end of the second lever that contacts the first lever and is perpendicular to the measuring surface of the X-axis measuring head of the first lever so as to contact the side cutting edge of the cutting tool. Z with the measurement plane parallel to the pin
A cutting edge positioning device equipped with an axis measuring element.