JPS59124551A - Four-shaft copying device - Google Patents

Abstract

PURPOSE:To improve the follow-up property of a processing head by offsetting the axial center of a rotation supporting shaft from the center of the copying end part of a stylus, and turning said end part along the uneven surface when the copying end part makes close contact with the unevenness on a curved surface of a copying mold. CONSTITUTION:When a detecting device 1 is fed in the arrow C direction, and a copying head 16 makes contact with the inclined surface of a copying mold 7, moment inclined upward is applied to the copying head 16, allowing a stylus 2 to be turned along a convex part 7A. A pulse signal conforming to a turning speed and a turning angle at that time is oututted from a rotation detector 4 due to said turning, sent to a comparing and subtracting part 29 after F/V conversion 28, and is compared with a prescribed copying feed velosity signal V0 set by means of a volume 25. Then, the deviation signal is inputted into a copying control device 21, and copying feed speeds in the three axial directions of the processing head 20 are reduced. Simultaneously, a servomotor 27 is controlled via a turning servomotor control circuit 24, allowing the turning of the processing head 20 to be controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a four-axis copying device that adds turning control to control in five orthogonal axes directions.

2. Description of the Related Art Conventionally, a copying device has been known in which a stylus is moved to follow a copying die and displaced in an orthogonal axis direction, and a workpiece is machined by driving a processing head based on the displacement. In this conventional copying device, the shape of the stylus is symmetrical about the tracer axis, and this shape is intended for a copying machine tool that controls six orthogonal axes. When forming a curved surface with many irregularities on the workpiece, it is necessary to make the cutting tool long (or thin) to form irregularities with good accuracy, which limits the cutting tool diameter, and also requires a sharp, almost vertical cutting tool. When forming irregularities, the cutting tool may bite or escape, which has the drawback of reducing machining accuracy and efficiency.

The present invention has been made in view of the drawbacks of the prior art described above, and an object of the present invention is to provide a 4-axis copying device that is capable of processing a curved surface with severe irregularities with high precision and efficiency. The feature of the present invention is that the axial center of the rotation support shaft and the center of the profiling end of the stylus are offset, so that when the profiling end comes into contact with the unevenness on the curved surface of the profiling die, the profiling end of the stylus is offset. The object of the present invention is to make the end part turn unevenly and to reduce the scanning speed of the stylus according to the turning angle.Examples of the present invention will be described below with reference to the drawings. do.

In FIG. 1, 1 is a detection device for inclined machining,
This detection device 1 is generally composed of a stylus 2, a tracer head 3 as a displacement detection means, a rotation detector 4 as a rotation angle detection means, a rotation shaft 5 as a rotation support shaft, and a housing 6. The stylus 2 is slid along the copying die 7 and is displaced in three orthogonal axes directions,
This displacement of the stylus 2 in the three orthogonal axes directions is detected by the tracer head 3, and a detection signal is output. 8 is a detection shaft of the tracer head 6, 9 is a connecting shaft protruding from the housing 6, and the tracer head 6 is connected to the detection shaft 8 and the connecting shaft. are connected by a pole 10 and integrally connected to the housing 6. The pivot shaft 5 is connected to the housing 6 through bearings 11.12'i.
The housing 6 is rotatably attached to the housing 6, and one end thereof protrudes from the lower surface of the housing 6 and serves as a coupling portion 13.

The stylus 2 has an arm support portion 14 and a copying arm 15. Both 14 and 15 are inclined approximately in the shape of a . The stylus 2 is supported by the pivot shaft 5, with the end of the arm support member 14 screwed and fixed to the coupling portion 16 of the pivot shaft 5 by bolts 17, and the stylus 2 is supported by the pivot shaft 5. The displacement of the stylus 2 is transmitted to the tracer head 3 via the pivot shaft 5, the housing 6, and the connecting shaft 9. Sliding detection head 1
6' (il-), the axis center A of the rotating shaft 5 and the center B of this copying head 16 are offset, and when the detection head 16 collides with the unevenness on the copying die 7, As shown in Fig. 2, the rotation detector 4 rotates around the axis center A of the rotation shaft 5.The rotation detector 4 is disposed adjacent to the rotation shaft 5 in the housing 6, and 18 is the detection shaft. The rotation of the rotation shaft 5 is transmitted to the detection shaft 18 via the belt 19, and the rotation detector 4 generates a pulsed total rotation angle detection signal in accordance with the rotation angle and rotation speed of the stylus 2. FIG. 3 is a block diagram of a control circuit for controlling the processing head 20, which will be described later, by signals from the excavator 1. It is roughly composed of a copying control device 21 as an axial dividing section j means, a three-axis direction single servo motor drive circuit 22, an override command circuit 23 as a displacement speed command means, a swing servo motor control circuit 24, and a volume 25. The copying control device 21 receives a displacement detection signal from the tracer head 6 and a displacement speed command 1g from an override command circuit 23, which will be described later, and determines the displacement direction and displacement speed of the processing head 20 in the three orthogonal axes directions. , outputs the control number 46 to the 3-axis directional servo motor drive circuit 22. 26 is
A servo motor 27 drives the machining head 20 in six orthogonal axes, and a servo motor 27 rotates the machining head 20. A three-axis servo motor drive circuit 22 receives control signals from the copying control device 21, Based on the control signal No. 7, the servo motor 26 is driven in the X-axis, Y-axis, and Z-axis directions. The override command circuit 23
The override command circuit 26 is composed of a converter 28 and a comparing/subtracting section 29. Pulses from the rotation detector 4 are input manually to this override command circuit 26, and the F/V converter 28 converts the number of pulses of the pulse signal into a voltage. A volume 25 and the output side of this F/V converter 28 are connected to the comparing/subtracting section 29, and an override signal "■" indicating a predetermined copying feed speed designated by the volume 25 is converted into a signal ■l. Subtraction ■ of o and voltage signal ■l. -■l is comparison subtraction part 2
9, and the subtraction signal Vo-Vl is output to the tracing control device 21 as a displacement speed command (t4).In other words, the greater the turning angular velocity of the stylus 2, the greater the voltage signal 1. The override signal Vo is greatly reduced accordingly, and the displacement speed of the machining head 20 in the six orthogonal axes directions is reduced as the turning angular speed of the stylus 2 becomes larger.

A pulse signal from the rotation detector 4 is directly input to the swing servo motor control circuit 24, and based on this pulse signal, the bending needle 20 swings in synchronization with the swing speed and swing angular velocity of the stylus 2. The servo motor 27 is driven so as to

Next, the action will be explained.

In FIG. 2, if the detection device 1 is now being fed in the direction of arrow C and the copying tool 16 comes into contact with the inclined surface of the copying die 7, then this A moment acts in the direction, and the stylus 2 bends to the convex portion 7A and turns in the direction of the arrow E. At this time, the rotation detector 4 outputs a pulse signal corresponding to the rotation speed and rotation angle, and this pulse signal is input to the F/V converter 28 and converted into a voltage signal (1). The comparison and subtraction section 29 subtracts Vo-V, and the subtraction signal 1 is input to the copying control device 21, and the processing head 20 receives the subtraction signal 3.
The scanning speed in the axial direction is reduced. At the same time, the pulse signal from the rotation detector 4 is transmitted to the swing servo motor control circuit 2.
4 is also manually operated, so the machining head 20 is rotated in synchronization with the rotation of the stylus 2.

In other words, since the profiling speed of the sharpener in which the convex portion is formed by the throat 20 during machining is reduced, it is possible to prevent the cutter from biting in and escaping as much as possible.

4 and 5 show a nostylus for a processing head for a barrel-shaped cutter, and the arm support member 60 and copying arm 61 of this stylus 2' are not inclined; Part 3 near the left end in FIG. 4 of 60
1A, it is connected and supported by the pivot shaft 5, and the axial center N of the pivot shaft 5 and the center B' of the copying head 62 are offset. The other constituent elements are the same as those of the first embodiment, so the same constituent elements are given the same reference numerals and the explanation thereof will be omitted.

As explained above, according to the present invention, the axial center of the rotation support shaft and the center of the profiling end of the stylus are offset, and the profiling end contacts the unevenness on the curved surface of the profiling die. The tracing end is configured to rotate along the unevenness,
In addition, since the stylus tracing feed speed is reduced in accordance with the turning angular velocity, the 00 head can be synchronized with the stylus tracing displacement as much as possible since it traces the uneven parts of the machined surface. This makes it possible to minimize the amount of unprocessed material even when machining curved surfaces with severe irregularities.In addition, since the cutting tool rotates, the angle between the cutting surface and the cutting edge of the cutting tool is relaxed, reducing sudden cutting resistance. Since there is no change and the machining becomes stable, it is possible to prevent the cutting tool from digging into the machining surface or escaping from the machining area as much as possible, resulting in high precision even when machining curved surfaces with severe irregularities. (And, it has the effect that the copying process can be performed efficiently.

Furthermore, since the cutting tool can follow the displacement of the stylus's tracing head as much as possible, it is possible to prevent the fine details of the machining direction from skipping over parts, and compared to conventional tools, it is possible to use cutting tools with a dog-edge radius such as barrel-shaped tools. Since it can be used, the number of cusps after processing can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the detection device for inclined machining, FIG. 2 is an explanatory diagram for explaining the rotation of the detection head of the stylus,
FIG. 6 is a block diagram of the control circuit, FIG. 4 is a top view of the detection device for the processing head for barrel-shaped cutting tools, and FIG. 5 is its front view. 2... Stylus 6, 62... Tracer head 4... Rotation detector 5... Rotation axis 7.
...Copying die 16...Copying head 20...
Processing head 21... Copying control device 23...
Override command circuit 24...Turning servo motor control circuit Patent applicant Toyota Motor Corporation

Claims (1)

[Claims] (1) A stylus that is slid along a copying die and displaced in three orthogonal axes directions, a processing head that is driven based on the movement of the stylus and processes a workpiece, and the copying die of the stylus. a rotational support shaft that supports the stylus so that its tracing end can be rotated in the υ direction around its axis, and that rotates in conjunction with the rotation; and a rotation angle of the stylus is detected via the rotational support shaft. a turning angle detecting means for outputting a turning angle detection signal; and a displacement detecting means connected to the stylus for detecting displacement of the stylus in six orthogonal axes along the tracing pattern and outputting a displacement detection signal. and an orthogonal axis direction speed control means for controlling the displacement speed of the processing head in three orthogonal axes directions, and receiving the turning angle detection signal and controlling the turning angle of the profiling end of the stylus with the profiling die. Displacement speed command means for determining a displacement speed and outputting a displacement speed command signal toward the orthogonal axis direction speed control means; Swing control means for swinging the machining head based on the swing angle detection signal. 4-axis copying device.