JP2001328066A - Grinding tool for processor and grinding method using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinding tool for a processor and a grinding method using it capable of conducting a cutting work and a grinding work at a machining center, and grinding a three-dimensional curved surface with high precision. SOLUTION: The grinding tool 20 is attached to and detached from the tip end part of a main shaft 1 in the machining center 10. A drive shaft 13 is slidable along with a guide hole 11. A compression coil spring 17 energizes the drive shaft 13 toward a work 53. The tip end tool 30 is provided on the other end of the drive shaft 13 and has degree of freedom in a vertical direction in relation to the surface of the work 53.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing tool for a processing apparatus and a polishing method using the polishing tool, and more particularly to a machining center capable of performing a polishing operation in addition to a cutting operation and capable of polishing a three-dimensional curved surface with high precision. The present invention relates to a polishing tool for an apparatus and a polishing method using the polishing tool.

[0002]

2. Description of the Related Art Conventionally, when machining a mold having a three-dimensional curved surface, a machining center is used. When a cutting tool such as a ball end mill is attached to this machining center and cutting is performed at intervals of 0.1 to 0.2 mm, picks of about 5 to 10 μm remain on the die surface. Therefore, it is necessary to polish the remaining picks.

[0003]

However, when the polishing operation is performed by manual finishing, it is generally impossible to obtain a highly accurate finished dimension. This is considered to be due to the fact that the picks are partially dropped too much when dropped.

[0004] In addition, many processing sites do not have a dedicated machine for polishing work, and there is a demand for an improved polishing work method.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and a polishing tool for a processing apparatus capable of performing a polishing operation in addition to a cutting operation at a machining center and capable of polishing a three-dimensional curved surface with high accuracy, and the polishing tool. It is an object of the present invention to provide a polishing method using the same.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention (claim 1) is a polishing tool which can be attached to and detached from the front end of a spindle of a processing apparatus, and which grinds a workpiece by rotational power transmitted from the spindle. And the polishing tool is
Attachment / detachment means attached to / detached from the main spindle tip, a guide hole formed in the inside of the attachment / detachment axis, and one end is housed in the guide hole so as to be slidable along the guide hole,
A drive shaft having the other end protruding to the outside, elastic means housed in the guide hole, and biasing the drive shaft toward the work; And a polishing means having a degree of freedom in the vertical direction.

The processing apparatus is, for example, a three-axis or five-axis machining center. The attachment / detachment means is attached / detached to the tip of the spindle. The guide hole is formed in the inside of the attaching / detaching means in the axial direction. One end of the drive shaft is housed in the guide hole so as to be slidable along the guide hole, and the other end is projected outside.

The elastic means is housed in the guide hole,
Energize the drive shaft toward the work. The polishing means is provided at the other end of the drive shaft and has a degree of freedom in a direction perpendicular to the surface of the work.

Thus, the NC control is performed along the three-dimensional curved surface of the workpiece by using the processing device, and the three-dimensional curved surface can be polished.

Further, according to the present invention (claim 2), the polishing means includes a shaft which can be attached to and detached from the other end of the drive shaft, a sphere formed at an end of the shaft, A pad having a pin fixed to a predetermined peripheral portion, a groove in which the pin is slidably received, and a spherical bearing portion in which a predetermined peripheral portion of the sphere is stored at an inner upper portion; And a holding means for holding the ball so as to be rotatable and detachable with respect to the spherical body, and an abrasive fixed to the bottom of the pad.

The shaft can be attached to and detached from the other end of the drive shaft. The sphere is formed at the end of the shaft. The pin is fixed to a predetermined portion around the sphere. The pad is formed with a groove in which a pin is slidably housed and a spherical bearing portion in which a predetermined portion around a sphere is housed in an upper portion inside the pad.

When the pin is housed in the groove, the rotational power transmitted from the main shaft is transmitted to the pad via the pin. The holding means holds the pad rotatably around the sphere and detachably with respect to the sphere. The abrasive is fixed to the bottom of the pad.

This makes it easy to replace parts. Since the pad is rotated along the three-dimensional curved surface of the work, accurate polishing can be performed.

Further, the present invention (Claim 3) is a method for polishing the work using the polishing tool for a processing apparatus according to claim 1 or 2, wherein the polishing tool is provided with a cutting tool attached to the processing apparatus. After cutting the work in accordance with cutting data based on numerical control, the cutting tool is replaced with the polishing tool, a plurality of points located in a polishing path are extracted from the cutting data, and the plurality of points are theoretically determined in advance. Or, from the relationship between the pushing amount of the elastic means and the urging force obtained by experiments, add the pushing amount corresponding to the necessary urging force to the cutting data, control the axial position, and grind the workpiece. Features.

With the cutting tool attached to the processing device,
First, the work is cut according to cutting data based on numerical control. Next, the cutting tool is replaced with a polishing tool. Then, a plurality of points located in the polishing path are extracted from the cutting data. It is usually desirable to make the cutting pass and the polishing pass different.

For this reason, a plurality of points where the cutting path and the polishing path intersect are selected. The pressing force of the pad required for polishing can be determined from empirical values and theoretical values. Therefore, based on the relationship between the pushing amount of the elastic means and the biasing force obtained in advance by theory or experiment, the axial position is controlled by adding the pushing amount corresponding to the necessary biasing force to the cutting data. Polish the work.

[0017] Thus, using the same processing apparatus,
In addition, by using the common cutting data, efficient polishing control can be performed. The position adjustment between the processing device and the work only needs to be performed once, and the processing accuracy is improved.

[0018]

Embodiments of the present invention will be described below. FIG. 1 shows an overall configuration diagram of an embodiment of the present invention, and FIG. 2 shows a detailed view of a tip tool.

In FIG. 1, a three-axis machining center 1
The special arbor 3 of the polishing tool 20 is removably attached to the main shaft 1 of the "0". An insertion hole 5 having an opening at a lower end is formed inside the special arbor 3. A shank 7 is inserted and fixed inside the insertion hole 5, and a linear bush 9 with a flange is further inserted and fixed inside the shank 7.

A guide hole 11 is formed inside the linear bush 9 with the flange. Inside the guide hole 11, a drive shaft 13 having one end housed in the guide hole 11 and the other end protruding outside is provided. The drive shaft 13 is slidable in the axial direction along the guide hole 11.

At the upper end of the drive shaft 13, a shank sliding portion 14 having a larger diameter than the shaft of the drive shaft 13 which is slid with respect to the inside of the shank 7 is provided.
A compression coil spring retainer 15 is fixed to the upper end of the shank 7.

A compression coil spring 17 for applying a pressing force corresponding to the amount of deflection is inserted into the drive shaft 13 by applying a preload between the shank sliding portion 14 and the compression coil spring retainer 15. A spring guide 19 for preventing the compression coil spring 17 from falling due to centrifugal force is attached to the center of the upper end of the shank sliding portion 14 so as to be located inside the compression coil spring 17.

A cylindrical cam follower 21 is provided on the left side of the shank sliding portion 14. The cam follower 21 is slidable along a slide hole 23 formed in the axial direction. A tool storage hole 25 is provided inside the distal end of the drive shaft 13. The shaft 27 of the tip tool 30 shown in FIG. 2 is inserted into the tool storage hole 25, and is fixed by a hexagon socket set screw 28.

The lower part of the shaft 27 has a shaft body 27.
a, and a tapered shaft constricted portion 27b is formed below the shaft body 27a. Further, a sphere 29 is provided at the lower end of the shaft constricted portion 27b.

A pin 31 is fixed to the spherical body 29 so as to be directed toward the center of the spherical body from the near side in the figure. The pad 3 is arranged so that a predetermined portion around the spherical body 29 is stored from below.
3 are provided. The spherical bearing portion 33 a formed on the upper inside of the pad 33 is slidable around the sphere 29.

Further, a groove 35 in which the pin 31 is slidably housed is formed in an upper portion inside the pad 33. This groove 35 has a predetermined depth from the spherical bearing portion 33a.
Further, the pad 33 is formed in a streak shape in the height direction.

Above the maximum outer diameter position of the spherical body 29 of the pad 33, there is formed a tapered hole 37 which is expanded from the inside to the outside. A steel ball 39 is disposed inside the tapered hole 37.

A ring 38 is annularly fitted above the tapered hole 37. A concave portion 41 having a slightly smaller diameter than the lower peripheral portion is formed around the upper portion of the pad 33. A compression coil spring 43 is provided in the concave portion 41, and a cylindrical slider 45 is inserted from above from outside thereof.

A cut portion 47 is formed at the upper end inside the slider 45, and the lower end of the cut portion 47 is brought into contact with the ring 38. Pad 3
An abrasive 51 is fixed to the bottom of the base 3 with an adhesive via a buffer 49. The work 53 is polished by the polishing material 51.

In such a configuration, the machining center 10 conventionally made for cutting can be used for polishing. After the main shaft 1 of the machining center 10 is cut, a polishing tool 20 is attached in place of the cutting tool.

The tip tool 30 first pushes the slider 45 downward. At this time, the steel ball 39 can be easily moved left and right because of the allowance of the notch 47. In that state, groove 3
The spherical bearing portion 33a of the pad 33 is brought into contact with the sphere 29 while aligning the position of the
To release.

At this time, the slider 45 is pushed upward by the compression coil spring 43. And steel ball 39
Is pushed inward by the inner wall of the slider 45 and slightly protrudes from the inner opening of the tapered hole 37. Thus, the pad 33 is rotatable while being held around the sphere 29.

The vertical movement of the slider 45 causes the pad 3
3 is detachable from the sphere 29. Slider 45
Is stopped at an optimum position by the action of the ring 38. The ring 38 also prevents the slider 45 from coming off.

The tip tool 30 is set with a hexagon socket head set screw 28.
To the drive shaft 13. Tip tool 30
The necessary number of polishing tools 20 with different abrasive materials 51 are prepared for the polishing operation, and the tool length is measured in advance.

The machining center 10 shown in FIG. 1 has an automatic tool changer (hereinafter referred to as ATC) structure. Then, the mold as the work 53 is automatically positioned and fixed on a table of an automatic pallet changer (hereinafter, referred to as APC).

In the polishing tool 20, a tool length correction is set such that the drive shaft 13 is pushed in until the pressure required for polishing is obtained, based on the free length of the drive shaft 13 when no load is applied. Is done.

At this time, a plurality of points located in the polishing path are extracted from the cutting data. Then, a tool length correction amount, which is a pushing amount, is added to the extracted data to obtain polishing data. At this time, a pressing force corresponding to the pushing amount is generated toward the work 53.

Thereafter, an NC program in which the polishing data has been input in advance is operated. APC draws the work 53 into the machining center 10 and ATC uses the polishing tool 2
0 is attached to the main shaft 1 of the machining center 10.

The spindle 1 is moved to the polishing start position, and the spindle 1 is also moved to a position where the spindle 1 comes into contact with the front end of the machining center 10 and the work surface of the work 53. At this time, the rotation of the tip tool 30 results in the posture along the three-dimensional curved surface.

Thereafter, the main spindle 1 is adjusted to the desired working pressure.
Press further. At this time, the drive shaft 13 can move smoothly by the guide action of the flanged linear bush 9. This pushing causes the compression coil spring 1
7 bends and generates the pressure required for processing. FIG. 1 shows the state at this time.

Next, the coolant is taken out and fed simultaneously with the rotation of the spindle 1. The main shaft 1 moves while maintaining the distance from the processing surface of the work 53. The rotational power of the main shaft 1 is transmitted to the special arbor 3 of the polishing tool 20, and further drives the drive shaft 13 via the cam follower 21.
Since the cam follower 21 is slidable along the slide hole 23, the pressure applied to the work 53 is balanced and averaged.

For the feed, a polishing range and a tool path are created exclusively for polishing from the data of the three-dimensional curved surface, and the starting position and the pattern are changed so that the tip tool 30 does not pass through the same route. Control is performed while maintaining a height at which a pressing force required for polishing is obtained. 3D surface and spindle 1
Is absorbed by the rotation of the tool bit 30.

The five-axis machining center can cope with a more complicated three-dimensional machined surface. The replacement of the polishing material 51 during polishing is performed by the ATC of the machining center 10.
The polishing tool 20 is replaced every time. Further, since the exchange of the work 53 can be performed by the APC of the machining center 10, a long-time polishing operation can be performed by an unattended operation.

[0044]

As described above, according to the present invention, it is possible to use a processing apparatus for polishing work, and at a small cost, high-precision polishing which is not inferior to that of a mold polishing machine, and a long time. Unmanned driving can be realized.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

Fig. 2 Detailed view of the tool bit

[Explanation of symbols]

 Reference Signs List 1 spindle 3 special arbor 7 shank 9 linear bush with flange 10 machining center 11 guide hole 13 drive shaft 14 shank sliding part 19 spring guide 20 polishing tool 21 cam follower 23 slide hole 25 tool storage hole 27 shaft 29 sphere 30 tip tool 31 pin 33 pad 33a Spherical bearing part 35 Groove 37 Tapered hole 38 Ring 39 Steel ball 45 Slider 49 Buffer material 51 Abrasive material 53 Work

Claims (3)

[Claims] 1. A polishing tool that can be attached to and detached from a tip of a spindle of a processing device, and that polishes a workpiece by rotational power transmitted from the spindle. The polishing tool is attached to and detached from the tip of the spindle. A detachable means, a guide hole formed in the detachable means in the axial direction, and one end is housed in the guide hole so as to be slidable along the guide hole, and the other end is projected outside. A drive shaft, resilient means housed in the guide hole and biasing the drive shaft toward the work, disposed at the other end of the drive shaft, and having a degree of freedom in a direction perpendicular to the surface of the work. A polishing tool for a processing apparatus, comprising: 2. The polishing means includes: a shaft that can be attached to and detached from the other end of the drive shaft; a sphere formed at an end of the shaft; and a pin fixed to a predetermined portion around the sphere. A pad formed with a groove in which the pin is slidably housed and a spherical bearing portion in which a predetermined portion around the sphere is housed, and a pad rotatably and slidably around the sphere; 2. A polishing tool for a processing apparatus according to claim 1, further comprising: holding means for detachably holding the polishing pad; and an abrasive fixed to a bottom of the pad. 3. A method for polishing the work using the polishing tool for a processing apparatus according to claim 1 or 2, wherein the cutting tool mounted on the processing apparatus is used to cut the work based on numerical control. After cutting according to
The cutting tool is exchanged for the polishing tool, a plurality of points located in the polishing path are extracted from the cutting data, and the pushing amount and the urging force of the elastic means are determined in advance by a theory or an experiment. A polishing method for polishing the work by adding an indentation amount corresponding to a necessary urging force to the cutting data to control the axial position.