JPH0639663A - Three-dimensional work machine - Google Patents

Abstract

PURPOSE:To provide a three-dimensional work machine in which the rotating operation component part of a rotary tool is improved so as to widen a space for workpiece, and the rigidity of the machine is improved. CONSTITUTION:The work machine in this invention has a three-spindle movable carriage 16 movable in the X, Y, and Z directions, and the movable carriage 16 is rotated by making the longitudinal and the lateral rotary axes as the rotation axes, making the tip of a rotary tool 2 as the center, while rotating the rotary tool 2 making its axis as the rotation axis. A circular arc guide 12 is used as to one side or both sides of the two rotation axes. The circular arc guide 12 consists of the combination of a V-groove and a rolling element or a needle, the combination of a circular arc guide member and plural rollers, or the combination of a V-shape guide member and plural rollers. Since any force from the external side has a balance within the width of the circular arc guide, no deformation such as the extension and the contraction of the diameter is generated in the circular arc guide 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a conventional rotary tool shaft and X,
The present invention relates to a processing machine composed of a Y- and Z-direction three-axis moving table, which has two rotating axes for swinging the tool tip back and forth around the space center and left and right. It is characterized by its use.

[0002]

2. Description of the Related Art Conventionally, in a method of processing a three-dimensional curved surface with an end mill, pick feeding of a ball end mill is usually performed.

[0003]

In the above conventional processing,
There is a problem that an arcuate groove remains on the finished surface.

In order to eliminate the above-mentioned problems, an extremely smooth surface is obtained by moving the axis of an end mill in which a circular cutting edge moves in a donut shape around the main shaft rotation axis so that it is always perpendicular to the machined surface. At that time, if the machining axis is tilted and the swing motion is swung back and forth and left and right around the tip of the tool, that is, near the machining part, the NC software for machine drive is extremely simple. There are various methods.

It is an object of the present invention to provide one of the swivel movement configurations, in which the swivel angle is not as large as ± 60 degrees or less, but there is a large space for the work piece and the machine. It provides a structure with extremely high rigidity.

[0006]

The most central turning method of the present invention uses an arc guide. Conventionally, there have been many examples such as dovetail method in which an arc is moved and fixed in a fixed position to be used, but none have realized high rigidity, high precision, and quick movement while receiving a load such as machining. The present invention realizes this unprecedented circular arc motion function by properly using the characteristics of rolling elements. Basically, the preload is applied to an arcuate V groove or guide through rolling elements or rollers. In this state, the moving body is brought into contact with and supported by.

[0007]

In the arc-shaped guide according to the present invention, the load from the outside is balanced within the width of the guide. Therefore, a force does not act in a direction that deforms the outer shape of the arc-shaped guide, and high rigidity, high accuracy, and quick movement can be realized.

[0008]

1 and 2 are perspective views showing a three-dimensional processing machine according to the present invention. The rotary tool 2 in FIG. 1 is supported so as to rotate about its central axis and also to rotate about rotary axes 4 and 6 that pass through its tip and are orthogonal to the central axis of the tool. That is, the support 10 that supports the main shaft 8 to which the rotary tool 2 is attached is supported so as to rotate with respect to the rotary shaft 6 by the arc guide 12 that is a feature of the present invention, and the arc guide 12 is also provided. Is attached to an L-shaped member 14 which rotates with respect to the axis of rotation 4. Further, the L-shaped member 14 is attached to the Z-direction moving portion 18 of the triaxial moving table 20 having the XY-direction moving table 16 for moving the workpiece in the XY directions.

FIG. 2 shows an example in which an arc guide is also used in the portion for rotating the rotary tool 2 with respect to the rotary shaft 4. By using the arc-shaped guide as described above, it is possible to avoid interference of the tool shaft or the driving portion and the holding portion thereof with respect to the workpiece, to obtain a wide machining range, and to obtain extremely high rigidity of the mechanical structure.

Next, the basic structure of the arc guide according to the present invention will be described. 3 is a sectional view showing a circular arc guide of the thrust type rolling element bearing type, and FIG. 4 is a plan view thereof. A typical example of a large-diameter, high-rigidity bearing is a cross roller bearing, which is often used in robots, but it is a radial type in structure. This shape cannot be used alone as a segment, and it is impossible to maintain high accuracy or even apply a preload to improve the turning accuracy. The present invention solves this problem by adopting the thrust rolling bearing type as the basic structure.

The movable body 26 sandwiched between the left and right fixed portions 22 and 24 in FIG. 3 is in contact with arcuate grooves 28 and 30 of V-shaped cross section provided on the surfaces facing each other at two locations, respectively, at four locations. It is guided through the rolling elements 32 so as to make an arc motion.

As shown in FIG. 5, each rolling element has a ball that hits each arc groove at two points, a cross roller that makes a line contact with the inner surface of the arc groove as shown in FIG. 6, or a roller as shown in FIG. There are 3 types of needles arranged in a mountain shape, and the moving body 2
6 is guided by this.

As shown by the arrow at the top of FIG.
By bringing 4 into parallel, an appropriate preload can be given to this rolling element 32, rigidity is increased, and further, a low resistance fine fluctuation range against a forward / reverse fluctuating load at the neutral position which occurs in the case of a smooth oil film guide is eliminated. be able to.

FIG. 8 is a half cross-sectional view showing a circular arc guide using the radial surface of the circular arc guide instead of the V-shaped circular arc grooves facing each other in a plane like the circular arc guide shown in FIG. Is a plan view thereof. A fixed portion 34 is formed with an arc guide portion 40 sandwiched between two grooves 36 and 38. Reference numeral 42 denotes a moving body, on the side surface of which there are a lower roller 44 and an upper roller 46.

In this example, there are two upper rollers 46 and one lower roller 44, but the upper roller 46 has an eccentric shaft, and the clearance adjustment or preloading as shown by the arrow is applied to the arc guide surface. Have a function. When the number of the upper rollers 46 is 2 and the number of the lower rollers 44 is 1, the central axis AA of the moving body 42 is adjusted by adjusting the eccentricity of the left and right upper rollers 46.
It can also serve as the easiest adjustment function for accurately matching the center O of the guide, that is, the turning center. If this concentric adjustment is not required, only one lower roller may be eccentric to apply the preload. As shown in FIG. 10, the rollers are arranged in a pair with the circular arc guide portion 40 sandwiched therebetween, and the pair of rollers are provided.
It is also possible to have a plurality of sets or more.

It is also possible to adopt a system in which the arc guide portion is formed as a single groove type so that the rollers are all housed in the groove and the preload is applied by adjusting the opening of the rollers. Further, in the example of FIG. 8, when the movable body 42 is sandwiched by the planes of the left and right fixed portions 34, the guides in the direction perpendicular to the arcuate movement surface have one to several rolling guides 48 introduced therebetween.
The clearance or preload can be adjusted by means such as the eccentric shaft.

Next, FIGS. 11 and 12 show a modification of FIG. As shown in the figure, the guide surface of the arc guide portion 40 has a tapered cross section, and the lower roller 44 and the upper roller 4
6 obliquely contacts this guide surface. As shown in FIG. 11, left and right preloads can be given by forming a pair of rollers on the left and right and further performing fine adjustment with an eccentric shaft, or by using an adjusting mechanism that brings a pair of arc guide parts 40 close to each other. it can. Further, since the rollers 44 and 46 hit the V-shape, this one set simultaneously guides the upper, lower, left and right sides.

As a simpler method, a V-shaped guide portion 50 having an arcuate shape and having a V-shaped guide surface and rollers 52 and 54 having a V-shaped outer peripheral surface shown in FIG. You can also FIG.
13A shows a V-shaped roller having a convex guide surface and a V-shaped groove, and FIG. 13B shows a concave V-shaped guide surface.
An example using an abacus bead roller having a shape guide portion and a convex V-shaped outer peripheral surface is shown. However, although this type has a commercially available product set, it has a drawback that the rigidity is significantly insufficient as compared with the examples of FIGS. 8 and 11.

In these examples, if the arc length of the arc guide portion is increased and the number of load rolling elements is increased, the angle and rigidity of the swing motion can be increased, but the space for the workpiece is reduced. On the contrary, if the sector angle is made small, the space becomes large, but the rigidity may become insufficient when the number of guides is one or the pair of left and right sides. From the above points, it may be considered that the normal swinging angle is a mechanism utilized when the swinging angle is about ± 60 degrees to ± 30 degrees. In the case of insufficient rigidity, the one shown in Fig. 3 has two large and small guides on one side and a total of four guides on the left and right to increase the rigidity. Can be made rigid. Note that these rolling element guides may be partially or wholly replaced with sliding surface guides that are in flat contact when the requirements for accuracy and rigidity are not high.

Further, if a swinging angle of ± 60 ° to ± 30 ° is taken, compared to a mechanism of a large free angle of ± 90 ° to ± 180 °, for a tilted surface having a swinging angle of this swinging angle or more. The end face of the donut end mill cannot be used for smoothing, leaving a very inconvenient point.
In this case, it is also an important component of the present invention to use the compound curved surface cutter shown in FIG. 14 to switch the vertical surface to a processing similar to that of a normal ball end mill having a slightly larger diameter.

In FIG. 14, OO is a spindle, that is, a rotating shaft of a cutter, an end mill, or the like. In a normal donut-shaped end mill, the arc-shaped cutter blade with radius r1
The cutting rotation is performed around the OO axis with a radius of 2. In the case of three-dimensional processing, the swing is performed around the center a of this end tangent plane or its upper and lower neighborhoods. In this compound cutter, this r1
It touches the circle at point b and smoothly connects to the ball end mill cutting edge r3 arc centered at point c. When machining an upright surface, the center of swinging and swinging is extended by d in the cutter axial direction, and switching is performed so that the center c passes through a locus separated by r3 from the machined surface as in a normal ball end mill. In that case, it is quite different from the center of rotation where the cutting speed is usually close to zero and the machining capacity is poor when the end mill is flat, and the outer peripheral part with the highest cutting ability is always applied to the machining surface. it can.

Furthermore, in a normal 3-axis to 5-axis machine, only a part of the cutting edge is liable to be overused because the part on which the cutter hits is always specified. It is not impossible to shift the hitting part by changing the angle of the main axis in a normal 5-axis machine, but since a huge amount of calculation software is required to compensate for the positional deviation that occurs, it is actually It is impossible. However, in the processing machine having the function of inclining like a swivel according to the present invention, it is very difficult to freely change only the position of the outer peripheral cutting edge of r3 around the point c regardless of the software that follows the workpiece. This has the advantage that the cutter blades can be used up evenly and evenly.

The principle of the composite cutter of the present invention has been described above. If r1 = r2 is further set and r3 is selected as 2.5r1, a higher-order fine shape error correction is performed in addition to the first approximation. It is also a great feature that software can be extremely simplified.

[0024]

According to the present invention, by using the circular arc guide, it is possible to provide a processing machine which has a large space for a workpiece and has a rotary tool revolving structure with extremely high machine rigidity. .

[Brief description of drawings]

FIG. 1 is a perspective view showing a three-dimensional processing machine according to the present invention.

FIG. 2 is a perspective view showing a three-dimensional processing machine according to the present invention.

FIG. 3 is a sectional view showing a circular arc guide of a thrust type rolling element bearing type.

FIG. 4 is a plan view of the circular arc guide shown in FIG.

5 is a cross-sectional view showing the rolling element shown in FIG.

FIG. 6 is a cross-sectional view showing the rolling element shown in FIG.

FIG. 7 is a cross-sectional view showing the rolling element shown in FIG.

FIG. 8 is a half sectional view showing an arc guide using a radial surface of the arc guide.

9 is a plan view of the circular arc guide shown in FIG.

FIG. 10 is a plan view showing an example of changing the arrangement of the rollers shown in FIG.

11 is a cross-sectional view showing a modified example of the arc guide shown in FIG.

FIG. 12 is a plan view of the circular arc guide shown in FIG.

FIG. 13 is a sectional view showing another arc guide according to the present invention.

FIG. 14 is a side view showing a compound curved surface cutter used in the processing machine of the present invention.

[Simple explanation of symbols]

 2 rotary tools 4 and 6 rotary shaft 8 main spindle 10 support 12 arc guide 14 L-shaped member 20 triaxial moving base

[Procedure amendment]

[Submission date] July 27, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 4]

[Figure 5]

[Figure 6]

[Figure 7]

[Figure 8]

[Figure 9]

[Figure 10]

[Fig. 13]

FIG. 11

[Fig. 12]

FIG. 14

Claims (4)

[Claims] 1. A rotary tool having a three-axis moving base movable in X, Y, and Z directions to rotate a rotary tool about its central axis and to rotate the rotary tool forward, backward, leftward, and rightward about a tip of the rotary tool. 2. Description of the Related Art In a processing machine that rotates with a shaft as a rotation axis, a fixed part and a moving body having arcuate grooves of V-shaped cross-section on mutually facing surfaces, and two sloped surfaces of each arcuate groove of the fixed part and the movable body are provided at two locations respectively. A three-dimensional processing machine characterized in that it is rotatable about one or both of the two rotating shafts by using an arc guide consisting of rolling elements that come into contact with each other at a location. 2. A rotary tool having a three-axis moving base movable in X, Y, and Z directions to rotate a rotary tool about its central axis and to rotate the rotary tool forward, backward, left, and right around the tip of the rotary tool. In a processing machine that rotates about a shaft as a rotation axis, a fixed portion and a moving body each having an arc groove having a V-shaped cross section and a mountain-shaped convex portion at a position facing the arc groove, and an arc groove of the fixed portion and the movable body. And a pair of needles each of which comes into contact with each of the slopes of the convex portion at two points, and is rotatable about one or both of the two rotation axes using a circular arc guide. 3. A rotary tool having a three-axis moving base movable in X, Y, and Z directions to rotate a rotary tool about its central axis and to rotate the rotary tool forward, backward, leftward, and rightward about a tip of the rotary tool. In a processing machine that rotates about an axis as a rotation axis, an arc including a circular arc guide portion and a moving body having a plurality of rollers that contact the outer peripheral surface and the inner peripheral surface of the circular arc guide portion and sandwich the circular arc guide portion. A three-dimensional processing machine characterized in that it is rotatable about one or both of the two rotation axes using a guide. 4. A rotary tool having a three-axis moving base movable in X, Y, and Z directions to rotate a rotary tool about its central axis and to rotate the rotary tool forward, backward, leftward, and rightward about a tip of the rotary tool. In a processing machine for rotating a shaft as a rotation axis, a V-shaped guide portion having an arcuate shape and having a convex or concave V-shaped surface on its outer peripheral surface and inner peripheral surface, and a V-shaped surface of the V-shaped guide portion. A movable body having a concave or convex V-shaped surface conforming to and having a plurality of rollers sandwiching the V-shaped guide, and an arc guide comprising A three-dimensional processing machine characterized by doing.