JP2000141115A - Cutting device, method for cutting work and manufacture of die. - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting device capable of forming an inclined surface by controlling it by a simple program in a short time without requiring a repair, and a method for the cutting work using the cutting device. SOLUTION: This cutting device is equipped with a rotation shaft 5 rotating with a cutting tool 7 attached, magnetic bearings 61-63, 71-73 to support the rotation shaft 5 with a designated amount of inclination applied against workpiece W and a motor 4 to rotate the rotating shaft 5 with the shaft inclined and supported by the magnetic bearings 61-63, 71-73. By using this cutting device, an inclined surface is formed by abutting the rotating shaft 5 onto the workpiece W and cutting its surface while rotating the shaft with the designated inclination applied against the workpiece W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting apparatus, a cutting method, and a method of manufacturing a die for cutting a workpiece by rotating a cutting tool to abut on a workpiece.

[0002]

2. Description of the Related Art Conventionally, a cutting apparatus which attaches a cutting tool such as an end mill to a rotating shaft such as a spindle and rotates the cutting tool has been widely used. Such a cutting device is used for various cutting processes such as a die manufacturing process as shown in FIG. 6 and a chamfering process of various parts, and a workpiece (work).
Is mounted on a work table, and a cutting tool is brought into contact with a workpiece while the work table and the cutting device are shifted in three X, Y, and Z axes perpendicular to each other to perform cutting.

Conventionally, when such a cutting device is used to perform chamfering, taper processing for providing a tapered portion for removal at the edge of a mold, or the like, conventionally, as shown in FIG. A plurality of small cuts were formed in a plurality of steps, processed into small steps, and then the inclined surface was smoothed by handwork such as sanding.

[0004]

However, in the above-described cutting method using the cutting device, it is necessary to divide the step into a plurality of steps to form one inclined surface, and it takes time. . In addition, the control program becomes longer, and it takes much time and effort to create the program. Furthermore, since the finished surface is completed in a step-like manner, it is necessary to manually adjust the surface to obtain a smooth surface.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and does not require any rework in a short time.
Further, it is an object of the present invention to provide a cutting device, a cutting method, and a method of manufacturing a mold, which can form an inclined surface by controlling with a simple program.

[0006]

In order to achieve the above-mentioned object, the present invention provides a rotating shaft on which a cutting tool is mounted and which rotates, a shaft supporting means for supporting the rotating shaft, and a shaft supporting means. Rotating means for rotating the supported rotating shaft while being supported by the supporting means, the supporting means rotating the rotating shaft by a predetermined amount of inclination with respect to the workpiece. By providing a cutting device capable of setting an inclined cutting mode for pivoting in a state of being inclined by a minute and a normal cutting mode for pivotally supporting the rotating shaft in a non-inclined state,
The above objective is achieved.

According to another aspect of the present invention, there is provided a cutting method for performing a cutting process by bringing a cutting tool supported by a rotating shaft into contact with a workpiece while rotating the cutting tool together with the rotating shaft. And an inclined cutting process in which the rotary shaft is rotated in a state where the rotary shaft is tilted and supported by a predetermined tilt amount with respect to the workpiece to perform cutting, and a cutting process is performed in which the rotary shaft is rotated in a non-tilted state. The object is achieved by providing a cutting method including a normal cutting step.

In order to achieve the above object, the present invention attains the above object by providing a method for manufacturing a mold in which a tapered portion is formed by cutting the edge of the mold by the inclined cutting process.

In the cutting apparatus, the cutting method, and the method of manufacturing a mold according to the present invention, the rotary shaft is rotated while being inclined with respect to the workpiece, and the cutting tool is obliquely brought into contact with the workpiece. Then, the inclined surface is directly cut and formed. Therefore, since the inclined surface can be cut and formed by a single processing, the processing time is remarkably reduced as compared with the case where the processing is performed in a plurality of steps in a stepwise manner. In addition, a control program for forming an inclined surface can be shortened, and can be easily and accurately created in a short time. Furthermore, since a smooth inclined surface can be formed by cutting, manual work such as applying a file after machining with a cutting device is not required.

[0010] In the present invention, the rotating shaft is preferably supported by a magnetic bearing. This is because the amount of inclination of the rotating shaft can be adjusted to a small amount, and an inclined surface with a slight inclination can be formed by cutting. In the taper processing or the like of the edge portion of the mold, it is preferable that the rotating shaft is particularly supported by a magnetic bearing in order to form a sufficiently inclined surface in one unit. In addition, by supporting the rotating shaft with magnetic bearings, when the rotating shaft is tilted and supported, a larger exciting current flows to support it with high rigidity, and even if the distance between the rotating shaft and its surroundings is short, the rotating shaft is It is possible to satisfactorily avoid contact with these members, and prevent a decrease in rotational accuracy and durability. Further, in the present invention, when the rotating shaft is inclinedly supported, it is preferable that the vicinity of both ends of the rotating shaft be offset by the same amount in opposite directions. The amount of movement of the rotation axis in the X and Y directions is smaller than in the case where only one end is offset, so that the same amount of inclination can be obtained, and the distance between the rotation axis and the surroundings can be set narrower. is there.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing one embodiment of a cutting device of the present invention. The cutting device according to the present embodiment is shown in FIG.
As shown in FIG.
The work table 1 is movable in three axial directions (the direction of arrow A in the figure, the direction of the front and back of the page, and the direction of arrow B in the figure), the spindle motor 2 is fixedly arranged, and the work table 1 and the spindle motor 2 are fixed. And a control unit for controlling.

The spindle motor 2 includes a motor 4, a rotating shaft 5 rotated by the motor 4, and a magnetic bearing of the rotating shaft 5 in a casing 3. The rotating shaft 5 has a grip 51 at one end on the work table 1 side, and the grip 51 is exposed from the casing 3. Then, the cutting tool 7 is held by the holding portion 51,
The cutting tool 7 is rotated by the motor 4 together with the rotating shaft 5.

The magnetic bearing has a thrust bearing disk 61 fixed coaxially to the rotating shaft 5 and rotating integrally with the rotating shaft 5.
An axial electromagnet 62 for generating an axial magnetic force; and an axial position sensor 63 for detecting the axial position of the rotating shaft 5.
And The axial electromagnets 62 are arranged so as to form a pair facing each other in the thrust direction with the thrust bearing disk 61 interposed therebetween, and the axial magnetic force of the axial electromagnet 62 acts on the thrust bearing disk 61. The thrust bearing disk 61 is supported in the thrust direction. The axial position sensor 63 outputs a position detection signal corresponding to the axial position of the rotating shaft 5 to the control unit.
Then, the control unit controls the exciting current of the axial electromagnet 62 based on the position detection signal, and holds the rotating shaft 5 at a predetermined position in the axial direction.

The magnetic bearing includes a radial bearing sleeve 71 made of two cylindrical magnetic bodies fixed to both ends of the rotating shaft 5 and a radial electromagnet 72. FIG. 2 is a radial sectional view including a radial bearing sleeve 71 of a magnetic bearing. As shown in FIG. 2, the radial electromagnets 72 (72 a to 72 h) are vertically arranged around each radial bearing sleeve 71, two pairs each of a total of four (72 a to 72 d, 72 e to 72 h). ing. Each radial bearing sleeve 71 is supported in the radial direction by a radial magnetic force of the radial electromagnet 72.

In the vicinity of each radial bearing sleeve 71, as shown in FIG. 1, two pairs of radial position sensors 73 for detecting the position of the rotating shaft 5 in the radial direction are perpendicular to each other in the same manner as the radial electromagnets. A total of four (73a to 73d, 7
3e to 73h, of which 73b, 73d, 73f, and 73h are not shown), and outputs a position detection signal corresponding to the radial position of the rotating shaft 5 to the control unit. The control unit controls the exciting current of the radial electromagnet 72 based on the position detection signal to hold each radial bearing sleeve 71 at a predetermined position, thereby holding the rotating shaft 5 at a predetermined tilt amount. Has become.

FIG. 3 is a block diagram showing the control of the inclination of the rotating shaft in the cutting apparatus according to the present embodiment, and FIG. 4 is an explanatory diagram schematically showing a state in which the rotating shaft 5 is inclined. FIG. 3 shows the control of the position of the rotating shaft in the X-axis direction by the radial electromagnets 72a and 72c and the radial position sensors 73a and 73c.
The rotary shaft 5 is similarly controlled in the Y direction by the 2b, 72d and the radial position sensors 73b, 73d.

As shown in FIG. 3, the control unit 8 receives a signal from a radial position sensor 73 to determine the position of the rotary shaft 5 in the radial direction and an input from an operation input unit 9 to be described later. The memory 82 stores a mode to be performed, a target position of the rotary shaft 5 for tilting the rotary shaft 5 to a predetermined tilt amount, various control programs, and the like, and a radial electromagnet 72 based on a signal from a position detector 81. A control circuit 84 that electrically controls the magnetic force of the rotary shaft 5 to be maintained at a predetermined target position, and a CPU 83 that controls the control circuit 84 based on a mode stored in the memory 82. I have.

When the rotating shaft 5 is inclined, CP
The signals input from the radial position sensor 73 to the respective control circuits 84 are corrected in the opposite directions by the signal from the U 83 in the opposite directions, and the target of the rotary shaft 5 by the radial electromagnets 72 near both ends of the rotary shaft 5 is set. When the position is supported in the standard direction, electrical control is performed so that the positions are opposite to each other from the standard position. Therefore, in the present embodiment, as shown in FIG. 4, almost the center of the rotating shaft 5 in the axial direction is always supported at a fixed point, and both ends are in the opposite directions in the X-axis direction and the Y-axis direction by the same amount (ε). And -ε) offset arrangement.

The cutting device according to the present embodiment includes an operation input unit 9, and the rotary shaft 5 is moved from the operation input unit 9 to Z.
The operator has a normal cutting mode in which the rotation axis 5 is supported in a standard direction parallel to the axis and perpendicular to the X axis and the Y axis, and an edge processing mode (inclined cutting mode) in which the rotation axis 5 is supported slightly inclined from the standard direction. Can be selected and set with the input by. When the edge machining mode is selected by controlling the exciting current to the radial electromagnet 72, the control unit 8 stores the rotary shaft 5 in the memory of the control unit 8 in advance in the Z-axis direction. The rotating shaft 5 is held parallel to the Z-axis direction in the normal cutting mode. Further, in the edge machining mode, the control unit 8
An exciting current larger than that in the normal cutting mode is supplied to the radial electromagnet 72 to support the rotating shaft 5 with higher rigidity than in the normal cutting mode. Thereby, even if the rotating shaft 5 is inclined and the distance between the rotating shaft 5 and the surrounding members such as the radial electromagnet 72 is short in a part, the rotating shaft 5 is prevented from coming into contact with those members, and the rotation accuracy and rotation accuracy can be improved. It is designed to prevent a decrease in durability.

Next, an embodiment of the cutting method of the present invention using the above-structured cutting device will be described.
In the present embodiment, the above-described cutting apparatus is used as a mold making apparatus, and the cutting method of the present invention is applied to a method of manufacturing a mold.

In the cutting method (mold manufacturing method) of the present embodiment using the above-described cutting device, first, the cutting device is set to the normal cutting mode by an input from the operation input unit 9. In the normal cutting mode, the rotating shaft 5 is held in the standard direction and rotated by the motor 4. Then, the work table 1 is moved by the same control as that in the related art, and a mold having a shape corresponding to the shape of the final product obtained by die cutting is formed. Thereafter, the cutting device is set to the edge machining mode by an input from the operation input unit 9. In this edge machining mode, the rotating shaft 5 is held and rotated while being inclined by a predetermined amount from the standard direction. Therefore, the cutting tool 7 held by the rotating shaft 5 also comes into contact with the workpiece (die) placed on the work table 1 while rotating with this inclination. Then, in this state, the edge of the mold having a shape corresponding to the shape of the final product is processed to form a tapered portion for taking out, and the formation of the mold is completed.

As described above, in the cutting device of the present embodiment,
An edge machining mode for rotating the rotating shaft 5 while tilting the rotating shaft 5 with respect to the Z axis is provided. Therefore, when performing the edge processing for removal, the cutting tool 7 can be obliquely brought into contact with the edge of the mold and the inclined surface (tapered surface) can be formed directly by this edge processing mode.

Since the taper surface can be cut and formed by a single process by performing the cutting process with the rotating shaft 5 being inclined, the machining process can be performed as compared with the case where the process is performed in a plurality of steps and the process is stepped. Time is significantly reduced. Further, a control program for edge processing can be shortened, and can be easily and accurately created in a short time. Further, since a smooth inclined surface can be formed only by cutting, manual work such as applying a file after machining with a cutting device is not required.

In this embodiment, since the rotating shaft 5 is supported by a magnetic bearing, the amount of inclination of the rotating shaft can be adjusted to a very small amount, and the inclined surface with a slight inclination can be cut and formed. It is suitable for tapering the edge of a mold.

The present invention is not limited to the above-described embodiment, and the shape, size, material, content of the process, and the like of each member can be appropriately changed without departing from the spirit of the present invention. It is. For example, in the above-described embodiment, the vicinity of both ends of the rotary shaft 5 is the same amount (ε and −
ε) The rotary shaft 5 is tilted by the offset arrangement. However, as shown in FIG. 5, only the one end of the rotary shaft 5 may be offset and the other end may always be supported at a fixed point. However, when the both ends of the rotary shaft 5 are offset as in the above-described embodiment, the amount of movement of the rotary shaft in the X and Y directions is smaller and the same amount of tilt is obtained as compared with the case where only one end is offset. Can be radial position sensor 72
There is an advantage that it is possible to narrowly set (design) the distance between the rotating shaft and the rotating shaft.

In the above-described embodiment, the normal cutting mode and the edge machining mode are switched by an input from the operation input unit 9, but may be automatically switched to the edge machining mode after the end of the cutting mode. In the above-described embodiment, in the edge machining mode, the rotation axis 5 is held by being tilted by a predetermined tilt amount based on the target position stored in the memory 82 in advance. The tilt amount stored in the memory 82 can be rewritten by an input from the controller or the like, and the rotation shaft 5 can be tilted and supported by a plurality of types or an arbitrary tilt amount.

The amount of inclination of the rotating shaft 5 is not constant, and may be changed depending on the portion of the workpiece (the relative position between the work table 1 and the spindle motor 2). Further, a pre-processing inclination amount detecting means for acquiring the inclination of the surface of the workpiece before the edge processing may be provided, and the inclination amount of the rotating shaft 5 may be changed according to the inclination of the surface before the processing.

In the above embodiment, the rotary shaft 5 is tilted. However, the entire spindle motor 2 is tilted, the work table W is tilted, and the workpiece is held not by the table but by the holding means fixed to the spindle. Then, the spindle may be tilted. When the rotating shaft 5 is inclined, it is preferable that the rotating shaft 5 is supported by a magnetic bearing as in the above-described embodiment. However, when the rotating shaft 5 is not inclined, depending on the number of rotations and other conditions, The rotating shaft 5 can be supported by another bearing.

The cutting device of the present invention is not used for manufacturing a mold,
For example, it may be used for a cutting process other than manufacturing and forming a mold, such as a chamfering process for various parts. The cutting method of the present invention can be a cutting method other than the manufacture of the mold, such as the chamfering of various parts, instead of the manufacture of the mold.

[0031]

As described above, according to the cutting apparatus, the cutting method, and the method for manufacturing the mold according to the present invention, it is possible to perform the control with a simple program without any need for rework in a short time. An inclined surface can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a cutting device according to the present invention.

FIG. 2 is a radial sectional view including the radial bearing sleeve of the embodiment of FIG. 1;

FIG. 3 is a block diagram illustrating control of a tilt of a rotation axis in the embodiment of FIG. 1;

FIG. 4 is an explanatory view schematically showing a state in which the rotation axis is inclined in the embodiment of FIG. 1;

FIG. 5 is an explanatory diagram schematically showing a state in which a rotation axis is inclinedly arranged in another embodiment of the present invention.

FIG. 6 is a diagram illustrating an example of a mold manufactured using a cutting device.

FIG. 7 is an explanatory view schematically showing chamfering and tapering by a conventional cutting device and cutting method.

[Explanation of symbols]

 Reference Signs List 1 work table 2 spindle motor 3 casing 4 motor 5 rotating shaft 7 cutting tool 8 control unit 9 operation input unit 51 grip unit 61 thrust bearing disc 62 axial electromagnet 63 axial position sensor 71 radial bearing sleeve 72 radial electromagnet 73 radial direction Position sensor 81 Position detector 82 Memory 83 CPU 84 Control circuit

Claims (6)

[Claims] A rotating shaft to which a cutting tool is attached and rotated; a shaft supporting means for supporting the rotating shaft; and a state in which the rotating shaft supported by the shaft supporting means is supported by the shaft supporting means. Rotating means that rotates while holding, the inclined support mode, the inclined cutting mode to pivotally support the rotating shaft in a state of being inclined by a predetermined amount of inclination with respect to the workpiece,
A cutting apparatus wherein a normal cutting mode in which the rotating shaft is supported in a non-tilted state can be set. 2. The magnetic bearing device according to claim 1, wherein the bearing means is a magnetic bearing that generates a magnetic force by an electromagnet at least in a radial direction between the rotating shaft and the rotating shaft to support the rotating shaft by the magnetic force. The cutting device according to claim 1, wherein both ends of the rotating shaft are supported at positions symmetrical to each other with respect to a non-inclined state. 3. The cutting device according to claim 2, wherein the shaft supporter supports the rotating shaft with a higher rigidity in the inclined cutting mode than when the rotating shaft is not tilted. 4. A cutting method in which a cutting tool supported on a rotating shaft is rotated along with the rotating shaft to abut on a workpiece to perform a cutting process, wherein the rotating shaft is moved relative to the workpiece. Includes an inclined cutting process in which cutting is performed by rotating in a state of being inclinedly supported by a predetermined amount of inclination, and a normal cutting process in which cutting is performed by rotating the rotating shaft in a non-inclined state. Cutting method. 5. The rotating shaft is supported at least in a radial direction by a magnetic bearing, and in the inclined cutting process, both ends of the rotating shaft are located at positions symmetrical to each other with respect to a non-inclined state. The cutting method according to claim 4, wherein the cutting method is supported. 6. A method for manufacturing a metal mold, wherein a tapered portion is formed by cutting the edge of the metal mold by the inclined cutting process according to claim 4 or 5.