JPH05318275A - Cutting tool supporting structure - Google Patents

Abstract

PURPOSE:To prevent generation of positioning error in precision relative positioning by introducing a constitution in which locating of a cutting tool relative to a work is executed precisely, and preventing a thermal expansion/ contraction of the tool due to temp. rise from arising on the tool side in case the tool is in continued service. CONSTITUTION:A cutting tool supporting structure concerned appears so that a cutting tool 56 to make cutting of a work upon receiving a torque is installed rigidly as consolidated with a rotary spindle 41, which is borne by a supporting member 35 on the body side of this cutting device concerned through static pressure supports 40, 38, 39, 37 and at the same time, is air cooled so that this 41 is prevented from expanding and contracting thermally in the thrust direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of performing precise relative positioning of a workpiece with respect to a cutting tool rotating at a high speed to perform cutting, and particularly to perform continuous cutting of fine grooves with high precision at a predetermined pitch. A suitable cutting tool support structure.

[0002]

2. Description of the Related Art In order to cut fine grooves with high accuracy,
The cutting work is performed by precisely positioning the work to be cut relative to the turning tool at high speed. A conventional machining procedure will be described with reference to the drawings. As shown in the front view of the cutting process state of FIG. 28A, a turning tool 124 is attached to the rotating shaft 122 by screwing or the like, and the rotating shaft 12
2 is rotated at a high speed in the direction of arrow J in the figure, and the work 128 fixed on the moving stage 126 is indicated by arrow H in the figure.
The groove of one groove is formed by cutting while moving in the direction.

Thereafter, as shown in the side view of FIG. 28 (b), the movable table 126 is moved by a predetermined pitch P in the direction of arrow I which is orthogonal to the direction of arrow J, and then the next groove is moved. The cutting work is performed, and thereafter, the cutting work is sequentially performed to obtain the finished work 128 shown in FIG. According to the above-mentioned conventional method, it is necessary to secure the machining accuracy of the work 128, and after one bite cutting process,
The work is purposely removed from the cutting device, the dimension of the portion to be cut is measured, and if the cutting amount is insufficient, the cutting amount is set and the cutting process is performed again.

[0004]

SUMMARY OF THE INVENTION Therefore, after the conventional cutting process is carried out once, the work is removed from the cutting device, the dimension of the cut portion is measured, and the depth of cut is reset. Then, it is proposed to improve the troublesome work of cutting again. For this reason, it is possible to realize a point of continuous cutting by providing the cutting device with positioning means for precisely positioning the cutting tool relative to the workpiece.

However, when the cutting tool is configured to perform precise relative positioning with respect to the work piece and the cutting tool is continuously used, thermal expansion / contraction of the cutting tool due to temperature rise is particularly rotatably supported for rotationally supporting the cutting tool. As a result of the remarkable occurrence in the axis, there is a problem that an error occurs in the precise relative positioning. Therefore, the supporting structure of the cutting tool of the present invention has been made in view of the above-mentioned problems, and an object thereof is to configure the cutting tool to perform precise relative positioning with respect to a workpiece, and to provide a cutting tool. The object of the present invention is to provide a support structure for a cutting tool that prevents thermal expansion / contraction of the cutting tool on the side of the cutting tool due to temperature rise when continuously used, and does not cause a precision relative positioning error.

[0006]

[Means for Solving the Problems] and

In order to achieve the above object and solve the problems,
The present invention is provided with the following structure, that is, a cutting tool support structure in which a cutting tool for cutting a workpiece by obtaining a rotational force is integrally provided with respect to a rotary spindle, and a main body of the cutting device. In the case where a cooling means for preventing the rotary main shaft axially supported against thermal expansion / contraction in the thrust direction is provided at the shaft supporting portion to raise the temperature by the cooling means and the cutting tool is used continuously or intermittently. Moreover, it works to prevent the thermal expansion and contraction of the cutting tool due to the temperature rise from occurring on the cutting tool side.

Further, preferably, the rotary spindle is supported by static pressure so that it can be freely inserted and removed in the radial direction and the thrust direction, and the cooling means is constructed by sending air to the static pressure supporting portion to form a cutting tool. When used continuously or intermittently, it works to prevent thermal expansion and contraction of the cutting tool due to temperature rise on the cutting tool side. Further, preferably, the rotating main shaft is directly engaged with an engaging portion formed at an end portion of an output shaft of an oil cooling type drive motor built in the main body to obtain the rotating force. As a result, the cutting tool can be directly connected to the drive motor, and when continuously or intermittently used, it functions to prevent thermal expansion / contraction of the cutting tool due to temperature rise from occurring on the cutting tool side.

Preferably, the rotary spindle and the cutting tool are formed of a predetermined metal material having a small coefficient of thermal expansion, and the thermal expansion of the cutting tool due to a temperature rise when the cutting tool is used continuously or intermittently. -It works to prevent shrinkage from occurring on the cutting tool side. And, preferably, a hard surface treatment is applied to the supporting portion of the rotary spindle to prevent damage at the time of insertion and removal, and thermal expansion and contraction of the cutting tool due to temperature rise when the cutting tool is used continuously or intermittently. Works to prevent the cutting tool from occurring on the cutting tool side.

[0009]

The following is an embodiment of the present invention, which is an example of a structure in which fine grooves are continuously cut on a work, and a plurality of fine grooves are cut on the work at intervals of a predetermined pitch of 10 to 100 μm. A processing example of processing and forming a die component for resin-processing the ink jet nozzle portion will be described in detail with reference to the drawings.

(Overall Structure) FIG. 1 is an external perspective view of an embodiment, with a part broken away. The schematic configuration will be described with reference to this figure. Three or more air cushions 2 are provided at the bottom of a base 1 which is a mounting base for each component described later, and absorbs external vibrations, which is harmful to cutting. Vibration is not transmitted to the base 1. This base 1
An X feed table 3 guided by the hydrostatic pressure is arranged directly above the so as to be driven in the X arrow direction in the drawing,
On the X feed table 3, a Z cutting table 4 is provided which is driven in the Z arrow direction orthogonal to the X feed table 3. A bearing part 5 is provided on the cutting table 4.
A work holding unit 100 composed of a holder 6 for holding a work is fixed.
The X feed table 3 and Z notch table 4
It is configured so as to move within a plane defined by the Z direction, so that the work can be precisely driven to a relative position with respect to a rotary cutting tool described later.

On the other hand, in the vertical direction of the base 1, a Y vertical table 14 is provided which is supported by hydrostatic pressure guides which are driven in directions orthogonal to the X feed table 3 and the Z cutting table 4, respectively. .. This Y upper and lower table 14
A main shaft portion 200 is fixed to the bracket via a bracket 9. As shown in the drawing, the main spindle portion 200 is composed of a main spindle body 7 and a bite holder 8. The bite 56 attached to the bite holder 8 is rotated at a high speed in the direction of arrow J in the drawing, and the base 1 Hydraulic cylinder 1 in the vertical arrow Y direction via steel belt 15 and pulley 16.
Precision drive is carried out by 8 while maintaining a balanced state.

A bracket 9 is attached to the Y upper and lower table 14.
Separately from the above, a bracket 10 is further fixed, and the vertical direction microscope 11 for observing the cutting work state of the work from above and below and the cutting work state of the work from the lateral direction along the above-mentioned XZ plane. The horizontal microscope 12 for observation is fixed. With the above schematic configuration,
While the work is cut, the shape and dimensions of the work are measured by the vertical microscope 11 and the horizontal microscope 12.

(Structure of Y Upper and Lower Table 14) Next, referring to FIG.
6 is a cross-sectional view showing a vertical drive configuration of the Y upper and lower tables, and in this figure, the Y upper and lower tables 14 are indicated by arrows Y
In order to precisely drive in the direction, the Y upper and lower table 14 is fixed at one end of a steel belt 15 which is guided by being turned by a pair of pulleys 16 that are rotatably supported at the ceiling of the base 1. Has been done. The other end of the steel belt 15 is connected to an actuator of a hydraulic cylinder 18 fixed to the base 1 via a chain 18a.

A balance weight 19 is mounted and fixed on the Y upper and lower table 14 so as to balance the weight of the spindle unit 200 described above. Also, hydraulic cylinder 1
Reference numeral 8 is connected to a hydraulic circuit, which will be described later, for balancing the main shaft portion B and the Y upper and lower table 14 to which the balance weight is fixed in the arrow Y direction. As described above, the Y up-and-down table 1 is vertically moved while maintaining the balance on the base 1.
The driving means 4 is screwed to a ball screw shaft 32, which is motive power transmitted via a clutch 31, to an output shaft of an up-down drive motor 17 fixed on the ceiling of the base 1 to convert rotational movement into reciprocating movement. The ball screw nut 22 is used. Therefore, both ends of the ball screw shaft 32 are rotatably supported on the base 1 by using bearings 48.

The ball screw nut 22 is built in and held by a notch-shaped hinge-like coupling 300, and the ball screw nut 22 and the Y upper and lower table 14 are connected by the coupling 300. When the Y up-and-down table 14 which is vertically driven in this way overruns downward, it abuts the stopper 21 fixed to the base 1 to stop the Y up-and-down table and is fixed in the middle of the ball screw shaft 32. The stopper 20 having an outer diameter smaller than the outer diameter of the ball screw nut 22 is brought into direct contact with the ball screw nut 22 to stop the ball screw nut 22 so that the ball screw nut 22 can move in the coupling 300 and damage to the ball screw nut 22 is prevented. is doing.

Next, FIG. 3 is a sectional view of an essential part of the Y upper and lower table 14 as viewed from the front, showing a schematic structure of the coupling 300. Further, FIG. 4 shows the coupling 30 of FIG.
5 is an external perspective view of the cutout hinge 25 that constitutes part 0 of FIG.
(A), (b) shows the operation | movement explanatory drawing of the notch hinge 25. As shown in FIG. First, in FIGS. 3 and 4, the Y upper and lower table 14 is guided in the vertical Y direction while being prevented from rattling by the porous plain bearing 14p embedded in the base 1, while the pair of steel belts 15 are connected to each other. It is fixed to the upper end and keeps the balance.

In order to transmit power by the vertical drive motor 17 to the Y vertical table 14 which is guided to move up and down in this way, the coupling 300 includes the notch hinge 25 and the connecting plates 23 and 24 at the upper part. It is provided on the side surface and fixed to the Y upper and lower table 14. This notch hinge 2
As shown in FIG. 4, in order to absorb the whirling of the built-in ball screw nut 22 in the a direction and the b direction, the opening 5a and the opening 25b are offset by 90 degrees and are integrally formed. The opening is elastically deformed so that external force around whirling can be absorbed.

That is, FIG. 5B is a schematic view of a parallel type notch hinge shown for comparison, and the ball screw shaft 32 is shown although the accommodation space may be smaller than that of the notch hinge 25 described above. When inserted as described above, the notch hinge 250 may be damaged as a result of a large compressive load being applied in the d direction, although a tensile load is applied in the c direction. Therefore, as shown in FIG. 5 (a), the series type notch hinge 25 formed to be long in the longitudinal direction of the ball screw shaft 32 has the same tensile load in the e direction and the f direction in the figure, and the notch hinge 25 On the other hand, the buckling load does not act and damage is prevented.

Next, FIG. 6 is a piping diagram of the hydraulic cylinder 18, showing a structure for keeping the supply pressure to the hydraulic cylinder 18 constant in order to stably drive the Y upper and lower table 14 in the vertical Y direction. As shown in the figure, a hydro tank 27 is connected in communication with a chamber formed by the piston of the hydraulic cylinder 18. In the other chamber, there is a pipe for keeping the supply pressure constant by a servo valve 29, and the accumulator 26 and the pressure sensor 28 are provided.
Servo valve 29 with filter 30 and pressure sensor 28
, As shown in the drawing. Through the above piping, the pressure sensor 28 measures the pressure, gives a command for the correction value to the servo valve 29, keeps the supply pressure of the hydraulic cylinder 18 constant, and causes the accumulator 26 to pulsate the supply pressure of the hydraulic cylinder 18. Has been removed.

(Structure of Main Shaft Part 200) The structure of the main shaft part 200 will be described with reference to the central sectional view of the main shaft part 200 in FIG. In FIG. 7, the spindle unit 200 is composed of a spindle body 7 and a motor unit 400.
The holder shaft 41 is provided so as to be easily attached to and detached from the rotating shaft of the. The holder shaft 41 has a bite holder 8 to which a bite 56 is fixed, which is fixed by bolting on the end face thereof, while an engaging portion 41h is integrally formed at the center portion of the other end, and is rotated through the engaging portion 41h. The drive force is transmitted. A flange portion 41f is integrally formed on the holder shaft 41, and the flange portion 41f is attached to a slider 36 described later.
The holder shaft 41 can be inserted and removed by moving the sliders 36a and 36b in the radial direction of the holder shaft 41 while sandwiching them by a and 36b to prevent the thrust shaft from coming off.

On the other hand, the housing 35 supporting the holder shaft 41 has a through hole 35a and a flange 35f formed integrally therewith. Cylindrical porous bearing 3
8 and 40 are embedded in the through hole portion 35a, while a disk-shaped porous bearing 39 is embedded in the side surface of the flange portion 35f as illustrated. Slider 3
6a and 36b are movably provided on the flange portion 35f to the positions shown by the solid line and the broken line in the figure, while partially fixing the disk-shaped porous bearings 37a and 37b, and the flange of the holder shaft 41. The portion 41f is held so as to be sandwiched between the portion 41f and the porous bearing 39.

Air is pumped to the above porous bearings,
The holder shaft 41 is supported by static pressure on the housing 35 in a non-contact manner. In addition, the stopper 42
The a and 42b are fixed to the sliders 36a and 36b, respectively, while the stoppers 44a and 44b are fixed to the outer peripheral surface of the flange portion 35f of the housing 35. When inserting / removing the holder shaft 41, the sliders 36a, 36b
These stoppers 43a, 43b and stoppers 44a,
The position is regulated by 44b, and it is manually operated so as to make a linear movement.

Next, the motor section 400 is constructed as a built-in motor 400, and the rotor 47 contained in the housing 49 and rotatably supported by the bearing 48 has the engaging section 41h of the holder shaft 41 described above.
An engaging hole 47a that engages with is formed, and
Coupling plate 45 and coupling rubber sheet 4
6 is provided in the engaging hole 47a of the rotor 47 as shown.

A cable connector 50 is provided on the housing 49.
Is attached to the lid 54, and the rotor 47 is attached.
A magnet 51 is fixed to the rotor, and a rotating magnetic field is generated in the stator coil 52 fixed to the lid 54 to rotate the rotor 47. Also, the lid 54 is an O-ring 5
It is attached via 3 so that the airtight state can be maintained. Further, since the housing 49 is attached to the housing 35 with bolts, the built-in motor 4
No. 00 can be easily removed from the main spindle body 7 by removing these bolts.

FIG. 8 is a diagram for explaining the insertion / removal of the holder shaft 41, showing the holder shaft 41 removed in the j direction. As described above, since the sliders 36a and 36b linearly move in the directions of the arrows g and h in the drawing, the holder shaft 41 can be exchanged while the sliders are moved outward and the stoppers 44a and 44b are in contact with each other. become.

Here, since the outer peripheral surface of the holder shaft 41 is chrome-plated, it is hard to be scratched,
Further, the rotational force i of the built-in motor 400 is transmitted to the holder shaft 41 by the coupling plate 45 via the coupling rubber sheet 46. Next, FIG. 9 is a cross-sectional view of the cooling component of the main shaft portion, in which an oil groove 57 formed in a spiral shape is formed on the outer peripheral surface of the housing 35, and through the O-rings 55, 56. The bracket 9 is fixed after being inserted into a hole 9a formed in the bracket 9. An oil pipe port 58 and a plug screw 59 are provided so as to communicate with the hole 9a.

On the other hand, the cover 60 has a built-in motor 40.
It is fixed to the bracket 9 so as to surround 0, and a shower box 61 having a large number of holes 61a formed in the bottom is provided therein. The shower box 61 has one end closed as shown in the drawing, and the mounting end communicates with the oil pipe port 58. An oil drain hose 62 is provided at the bottom of the cover 60 to drain oil. Further, a cooling air pipe inlet 63 and a cooling air pipe outlet 64 are fixed to the lid 54 described above.

With the above structure, the oil controlled to a constant temperature is circulated to the oil groove 57 through the oil pipe port 58 to cool the housing 35 and supply the oil into the shower box 61. Then built-in motor 4
Oil the entire outer surface of 00. After this, the cover 60
The oil accumulated on the inner bottom is discharged through the oil discharge hose 62. On the other hand, cooling air is injected from the cooling pipe inlet 63 toward the stator coil 52 and exhausted from the cooling air pipe outlet 64.

Since the holder shaft 41 is statically supported by the porous bearings 37a, 37b, 39 as described above, even if the housing 35 thermally expands due to the heat generated by the built-in motor 400, the range D2 in FIG. Since the influence of the amount of dimensional change due to the thermal expansion does not reach the holder shaft 41, the position of the cutting tool 56 is not affected. Further, by minimizing the size of the range D1 in the figure, the amount of dimensional change due to thermal expansion of the holder shaft 41 itself is minimized, and the displacement of the position of the cutting tool 56 is also minimized. Here, by using a low thermal expansion alloy for the holder shaft 41, the bite holder 8 and the bite 56, it is possible to further reduce the influence of thermal expansion.

(Structure of Z Cut Table 4) The structure of the Z cut table 4 fixed on the X feed table 3 described in FIG. 1 will be described. 10 is a partially cutaway plan view of the Z-cutting table 4, and FIG. 11 is H of FIG.
FIG. 6 is a cross-sectional view taken along the arrow H. In FIG. 10, a work holder for holding the work is fixed on the movable slide 76 of the Z-cutting table 4, and the Z-direction feed is performed.

This movable slide 76 is used for the X feed table 3
It is guided so as to move in the Z direction via a plurality of needle rollers 72 shown in FIG. 11 on a base 70 fixed above. In the mechanism for driving the movable slide 76 in the Z feed direction, a ball screw block 79 that is screwed onto an output feed screw shaft 77 of a Z motor 71 fixed on the base 70 is fixed to the bottom surface of the movable slide 76. , Z motor 71 is converted into linear motion. A guide member 70a whose both sides are precisely machined is fixed on the base 70, and a pressing roller 78b is pressed by a slide block 76a fixed on the movable slide 76 side and a coil spring 78b.
Thus, the guide member 70a is sandwiched from both sides so as to be movable in the Z direction, thereby preventing the rattling and enabling the movement.

On the other hand, on the outer wall of the movable slide 76, a bellows 74 that is capable of expanding and contracting in the Z direction is mounted and fixed as shown in the figure, and the lower end of the bellows 74 is attached to the base 70.
It is soaked in the oil stored in the oil tank 75 provided on the side. In this way, dust and cutting powder that enter through the gap between the movable slide 76 and the berth 70 are prevented. Further, the X feed table 3 which feeds in the X direction at the time of cutting is also constructed in substantially the same manner as the Z cut table 4.

(Structure of Work Holding Section) FIG. 12 is an external perspective view of an embodiment of the work holding section 100. In this figure, the work holding section 100 is detachable as will be described later. The holder 6 and the bearing portion 5 fixed on the Z-cutting table 4 are used to cut the workpiece 89 by the rotating cutting tool 56. 13 is a sectional view taken along the line EE of FIG.
12 is a sectional view taken along the line FF in FIG. 12, and FIG. 15 is GG in FIG.
The cross-sectional views are shown respectively.

First, in FIGS. 12, 13 and 14, the holder 6 is a main body part 81a which is statically supported by a porous air pad, and a work support part which is provided so as to rise from the substantial center of the main body part 81a. 81b and an upper surface portion 81c for fixing the work piece are integrally formed.
c is a mounting surface for the work 89. On the other hand, the structure of the bearing portion 5 that supports the holder 6 in a replaceable manner is shown in FIG.
The housing base 80a is fixed on the table 4 as shown in FIG.
After setting the housing upper lid portions 80b and 80c, which are fixed so as to partially cover the opening portion of the housing base portion 80a and allow the work supporting portion 81b to be inserted, and the holder 6, at a predetermined position, The housing lateral lid portion 8 fixed to the housing base portion 80a to form a lid.
It is composed of 0d.

Further, the direction in which the holder 6 is set at a predetermined position of the bearing portion 5 is made to coincide with the rotating direction of the cutting tool 56, so that the influence of the dimensional error when the holder 6 is set does not affect the cutting accuracy. There is. Further, in FIG. 12, an air pad 88 is fixed to one side surface of the housing base portion 80a, while a pair of air pads 87a, 8a is provided.
7b is fixed to the bottom surface. With the above configuration, when guiding the holder 6 in the direction of the arrow in the figure, the main body part 81
A is placed on the air pads 87a and 87b and abutted against the air pad 88 so that it can be moved to a predetermined position. Then the housing side cover 8
0d is fixed and brought into the state of FIG.

Next, referring to FIG. 13, the main body part 81a of the holder 6 has air pads 84a and 84b fixed to the opening side surface portions of the housing base portion 80a, air pads 83a fixed to the abutting portions, and a housing lateral portion. The four side surfaces of the air pads 83b fixed to the lid portion 80d are positionally regulated on the four side surfaces, and the air discharged through the air pads statically supports the housing base portion in a non-contact state.

On the other hand, the air pads for statically supporting the main body part 81a of the holder 6 in the vertical direction are shown in FIGS.
, The air pad 82c fixed on the bottom surface of the housing base 80a and the housing upper cover 80
It is composed of air pads 82a and 82b fixed to b and 80c. By sending air to each of these air pads, static pressure is supported in the vertical direction in a non-contact state with the housing. With the above configuration,
The housing side lid portion 80d is removed so that the holder 6 can be attached and detached. Further, each of the above air pads 8
Since static pressure is supported by the air blown into the minute gaps between the main body parts 81a and the parts 83, 84, wear is eliminated and the positioning reproducibility is maintained high even when the attachment and detachment is repeated many times.

Here, the holder 6 and the air pads 82, 8
Since it is difficult to attach the holder 6 directly to the housing base 80a because the gap between the holder 3 and 84 is very small, it is continuous with the one side pads 87a, 87b and 88 for guiding and guiding the holder 6 to the housing base 80a. The gap pads 85a, 85b, 86a, and 86b are provided so as to be arranged. The one-side pads 87a, 87b, 88 function as guide air pads for adjusting the posture by pressing the holder 6, while the gap pads 85a, 85
b, 86a and 86b are set to have a larger gap with the holder 6 than the air pads 82, 83 and 84 so that the holder 6 can be easily inserted and passed. This serves as a positioning for inserting the holder 6 into the air pads 82, 83, 84. These gap pads are installed vertically and horizontally as shown in FIGS. 13 and 14, but when the holder 6 is moved during the attachment process of the holder 6, the attitude adjustment in the vertical direction and the attitude in the horizontal direction are performed. The holder 6 is arranged on the air pads 82, 83, 84 by arranging the respective gap pads in a staggered manner so as not to simultaneously pass through the gap pads for adjustment and vertical position adjustment and horizontal position adjustment. You will be able to easily guide it.

As a result of the high positioning reproducibility of the holder for fixing the work as described above, if the work can be set up outside the machine and the position reproducibility on the machining tool side can be secured,
Even when the work process of the work is performed a plurality of times, it becomes unnecessary to readjust the work position every time the work is replaced, and the setup time can be greatly shortened. Further, the direction in which the air pad 83b supports the holder 6 is such that the housing lateral lid portion 80d to which the air pad 83b is attached when the holder 6 is attached or detached.
Although the positioning reproducibility is lower than other supporting directions for picking up, it is possible to reduce the influence on the machining accuracy due to the deterioration of positioning reproducibility by matching this take-out direction with the feed direction of cutting. .. Next, FIG. 16 is an external perspective view of the holder 6, FIG. 16A shows a modified example in which the main body part 81a of the holder 6 is circular, and FIG. 16B shows a modified example in which the main body part 81a is rectangular. Although the cylindrical holder shown in (a) is easier to manufacture than the polygonal columnar holder, it is necessary to add a rotation stopping mechanism.
Further, in the case of the rectangular or polygonal columnar holder having at least two pairs of parallel side surfaces 8e shown in (b), the detent mechanism is not necessary, and the housing can be made compact.

By making the polygon a square, the number of mounting directions can be maximized. For example, a rectangular shape has two directions, but a square shape as in the embodiment allows mounting in four directions. Further, in the case of a regular polygon, since the length of the outer circumference is longer than that of a circle having the same area, the area of the air pad that supports the outer circumference can be increased, and the support rigidity of the holder can be increased. In addition, the outer periphery of the holder 6 is designed to facilitate insertion.

FIG. 17A is a side view of the holder 6,
(B) is a plan view of the holder 6. First, FIG.
In (a), each ridge portion of the main body part 81a of the holder is subjected to inclination processing with a taper angle θ about the insertion direction. As a result, self-locking during insertion is prevented,
The insertion can be facilitated and the air pad can be prevented from being damaged when the main body part 81a of the holder and the air pads 82, 83 and 88 are in direct contact with each other. Further, as shown in (b), the side surface 81e of the main body part 81a is formed by a large arc Q, so that the side surface can be prevented from self-locking.

A procedure for inserting and setting the holder 6 described above into the bearing portion 5 will be described below with reference to FIGS. 18 (a) to 18 (c). In FIG. 18A, the holder 6 is first placed on the air pads 87a and 87b, and the posture in the vertical direction is adjusted. Next, when manually advancing in the direction of the arrow in the figure, vertical position adjustment is performed by the clearance pads 85a, 85b, 85c, 85d. After that, by further advancing as shown in FIG. 18C, the air pad 82a,
Vertical positioning is performed by 82b, 82c, and 82d. Similarly, in the left-right direction of the holder 6, after the posture in the left-right direction is adjusted by pressing the holder 6 on the one-side pad 88, the holder 6 passes through the gap pads 86a, 86b and is positioned by the air pads 84a, 84b in the left-right direction. Is done. Finally, as shown in FIG. 12, the air pad 83a and the air pad 83b attached to the housing 80d fix the positioning in the insertion direction.

As described above, the insertion is facilitated by adjusting the posture and position with respect to each air pad step by step. In addition, since each of the crests of the main body part 81a of the holder is tapered with the insertion direction as an axis as described above, self-locking is prevented. Further, it is possible to prevent the air pad from being damaged when the main body part 81a and the respective air pads come into direct contact with each other.

The bearing portion 5 described above is provided with measures against the intrusion of dust and cutting powder. FIG. 19 is a central cross-sectional view of the bearing portion 5 in which the holder 6 is built in, and the same reference numerals are given to the already described configurations. As shown in the figure, a first cover 130 having a vertical surface 130a continuously formed is fixed to the outer peripheral edge of the work attachment surface 81c. On the other hand, the second cover 131 and the third cover 132 are provided so as to surround the outside of the bearing portion 5, and the third cover 132 is detachably provided on the side surface of the housing base portion 80a using the bolt 133. There is. Further, a groove portion that partially penetrates into the vertical surface 130a of the first cover 130 is formed in each of the second cover and the third cover to ensure airtightness.

Further, the second cover 131 is an extension pipe of the air pad pipe so as to be a system different from the above-mentioned pipe for supplying air to each air pad, and the air pipe 134 for utilizing the exhaust gas. Is provided, and the supply air pressure Pa
Is fed into the cover so as to flow inside from between the third cover 132 and the first cover 130 to obtain the internal atmospheric pressure Pb.

As a result, the atmospheric pressure Pc outside the cover becomes lower than the internal atmospheric pressure Pb, but the internal atmospheric pressure Pb becomes lower than the supply air pressure Pa. As a result, Pa> Pb
> Pc, and since dust, oil mist, and cutting powder can be prevented from entering from the outside, the air pad and the holder body can always be maintained in an ideal state, so that the accuracy of the bearing portion 5 can be maintained.

Next, the structure of the overload detecting device connected to the bearing 5 and the holder 6 described above will be described. Figure 2
Reference numeral 0 is a block diagram of the entire apparatus, and as shown in the figure, the already described motors are connected to the control device 400 having a built-in drive circuit. On the other hand, the holder 6 and the bearing portion 5 are connected with an overload detection unit 151 connected to the overload detection device 152 so that an overload generated during cutting can be detected.

FIG. 21 is a circuit diagram of the overload detecting portion 151 connected to the bearing portion 5 and the holder 6, and the air pads 82a and 84a of the bearing portion 5 and the holder 6 are made of a conductive porous material such as graphite. The electrode 15 is made of a member.
3 and the electrode 154 are connected to the bearing portion 5 and the holder 6, respectively. Further, a closed circuit in which a power source V and a resistor R are connected in series is connected to the electrodes 153 and 154 as shown in the figure, and the overload detection unit 151 is configured by detecting the potential difference between both electrodes. is doing. This overload detection unit sends a detection signal to the control device 400 via the overload detection device 152.

In the above construction, when some abnormality occurs during machining of the work and an external force acts between the holder 6 and the bearing portion 5, when the air pads 82a and 84a come into contact with each other, the potential difference between the electrodes 153, 154 is generated. Changes appear in the overload detection device 1 by catching this change as an overload.
Send to 52. Therefore, the control device 400 sends a command to each drive unit to generate an abnormal signal and stop the work.

Therefore, even if an abnormality occurs during cutting of the work by the above-mentioned overload detection, the work can be interrupted, so that the cause of the abnormality can be removed and the work can be restarted. Especially when the entire device is program-controlled as described below,
If there is a program error or runaway, a collision occurs between the drive units, but damage to the air pad can be prevented by providing an abnormal overload detection device. For this reason, the overload detection device 152 is connected not only to the holder and the bearing portion, but also to the electrodes provided at each driving position.

(Structure of Microscope Section) FIG. 22 is a front view showing a mounted state of the microscope. In this figure, the main spindle section is mounted using the bracket 9 and moved up and down on the Y slide table 14 which is moved up and down. A vertical microscope 11 and a horizontal microscope 12 are attached in a horizontal direction and a horizontal direction by using a bracket 10 that is configured separately from the bracket 9. The vertical direction microscope 11 and the horizontal direction microscope 12 are provided with the objective lens 1 respectively.
03a, 103b and optical fiber mounting ports 105a, 105b for transmitting light incident from the light source and the CCD camera 104.
It is composed of a and 104b, is fixed to the support bases 106, 107, and 108 that constitute the bracket 10, and is configured to move up and down together with the Y slide table 14.

Here, since the cutting direction for cutting the work 89 with the cutting tool 56 and the rotation direction of the spindle are the same,
By mounting the horizontal microscope 12 in the direction opposite to the rotation direction of the main shaft, a burr 89h at the time of cutting is generated on the side opposite to the microscope unit 12. As a result, the image in which the cutting amount of the work 89 is displayed on the TV monitor through the CCD camera 104b becomes an easy-to-see image without the burr 89h. In addition, the light source of the microscope is placed away from the main axis and the microscope by using an optical fiber cable, and the structure is designed to suppress expansion due to heat of the light source as much as possible. Further, the main shaft and each microscope are not directly attached to the same bracket, but are separately attached to the slide 14 so that the vibration due to the rotation of the main shaft is less likely to be transmitted to the microscope unit. By mounting the microscope for measuring the work as described above, the work can be measured and the correction processing can be performed without removing the work on the apparatus.

(Explanation of Operation) FIG. 23 (a) is a front view of a work 89a on which precision cutting is fully automatically performed, and FIG. 23 (b) is a front view showing a sequence of precision cutting. First, FIG.
As shown in FIG. 9A, a plurality of minute grooves 89d shown by diagonal lines are cut and formed at a predetermined pitch on the upper edge of the work 89a. Further, niger groove portions 89c are similarly formed by cutting on both sides of the minute groove 89d. These grooves are pre-processed by using the above-mentioned cutting tool 56 as a forming tool and
Although the fine groove 89d is formed by cutting once, the cutting may be performed twice or more depending on the depth of the fine groove.

Next, as shown in the precision cutting processing sequence of (b), trial cutting is performed so that the right corner of the cutting tool 56 is located at the point U1. After this, point U1
The position is measured using a horizontal microscope and a vertical microscope. Subsequently, the correction values δz and δy up to the point U2 at the right corner of the leftmost position of the minute groove 89d, which has been input in advance, are obtained based on the measurement result at the point U1. After this,
The Z cutting table 4, the Y slide table 14, and the like are moved to a position where the right corner of the cutting tool 56 coincides with the point U2, and the fine groove 89d is cut. After that, all the minute grooves 89 are fed while feeding for a predetermined pitch.
The cutting process of d is performed.

FIG. 24 is an explanatory view of the precision cutting process sequence, in which the moving directions of the Z cutting table 4 are indicated by arrows Zf and Zb, and the moving directions of the Y upper and lower tables 14 are indicated by arrows Yu and Y.
In addition to being represented by d, the moving directions of the X-feed table 3 are represented by arrows Xr and Xl by an isometric drawing method, respectively. Further, the bite 56 is rotated in the direction of arrow J in the drawing as described above, but is controlled to start rotation at step S3 and stop rotation at step S28 described later. Further, the arrows S1 to Sn shown below the bite 56 are shown corresponding to the moving direction of each table, and are represented by the isometric drawing method corresponding to the step S of the drive control flow chart described later. ..

25 to 27 show a drive control flow chart, which is shown corresponding to FIG. 25 and 2
In step 4, the tool 56 is attached to the bite 56 bite holder 8 in step SP1 in the preparatory stage for driving the apparatus, and the position dimension of the bite 56 is measured and grasped by the pre-stage trial machining.
Input to the control device 400. After that, in step S1, the holder shaft 41 is inserted into the housing 35. On the other hand, in step SP2 in the preparation stage, the work 89a
Is fixed to the holder 6, and the dimensions of the work 89a are measured and grasped by the pre-stage trial machining and input to the control device 400.

Next, the holder 6 is inserted and fixed to the bearing portion 5 and air is sent to the air pad and the like. Step S
In 3, the rotation of the bite holder 8 is started in the direction of arrow J as shown in FIG. 24, the process proceeds to step S4, the Y upper and lower table 14 is lowered in the direction of arrow Yd, and the tip of the bite 56 is moved to the retreat point T. .. Subsequently, in step S5, the Z cutting table 4 is moved forward in the direction of arrow Zf, and in step S6, the X feed table 3 is fast-forwarded in the direction of arrow Xr so that the workpiece comes to the cutting start position. Following this, the cutting work shown by the broken line arrow in the figure is performed in step S7, and the trial work is completed.

After this, the process proceeds to step S8, the Z-cutting table 4 is moved backward in the direction of arrow Zb, and the X-feeding table 3 is moved at step S9 to move to the measuring position U1 by the horizontal microscope and the vertical microscope, In step S10, the trial machining in the Y and Z directions is measured, and the correction values δz and δy up to the point U2 at the right corner of the leftmost position of the minute groove 89d, which has been input in advance, are calculated.

Subsequently, as shown in the flow chart of FIG. 26, the process proceeds to step S11, where the Y upper and lower table 1
4 is moved by δy and the Z cutting table 4 in step S12 is moved by δz.
Preparation for processing of d is started. In the next step S13, the X feed table 3 is fast-forwarded in the direction of the arrow Xr so that the workpiece comes to the cutting start position, and in step S14, the first fine groove 89d is cut.

Then, in step S15, after the Z-cutting table 4 is moved backward in the direction of arrow Zb,
In step S16, the X feed table 3 is moved in the direction of the arrow Xl, but the amount of movement does not reach the measurement point U1 and the process moves to machining of adjacent minute grooves. In the next step S17, the Z-cutting table 4 is moved in the Zf direction by the amount corresponding to the predetermined pitch of the minute grooves, and the second minute groove is prepared for cutting.

Then, in step S18, the X feed table 3 is moved in the direction of the broken line arrow to cut the second minute groove. After that, the X feed table 3 is moved in the direction of the broken line arrow to perform cutting of the third and subsequent minute grooves, and in step S19, it is determined whether or not all the minute grooves have been processed, and the processing ends. If so, the process proceeds to step S20, the Z-cutting table 4 is retracted in the Zb direction, the process proceeds to step S21, and the X-feed table 3
Is moved in the Xl direction to move the work to the measurement point U1. In step S22, the dimension measurement by each microscope is executed, and if the standard is satisfied, the next step S23 is performed.
If the standard is not satisfied, the process returns to (a) in FIG. 25 and the re-cutting process is performed.

Next, in the flow chart of FIG.
In step S23, the Z cutting table 4 is moved backward (Zb
Direction) and the X feed table 3 is moved to the left (Xl direction) to the take-out position T. Following this, in step S24, the Y upper and lower table 14 is moved up in the Yu direction. Then, in step S25, the holder 6 to which the work is attached is extracted from the bearing portion 5 to obtain the work after cutting.

At the next step S26, it is determined whether similar processing is to be performed. If processing is performed, the process proceeds to (B) and processing is performed again. On the other hand, if the machining is not performed again, it is determined in step S27 whether or not another type of machining is performed. If another type of machining is performed, the process returns to the original process. If not, in step S28. The rotation of the bite holder 8 is stopped to finish the work.

The work obtained through the above cutting process has fine grooves processed with high precision, and therefore can be used as a mold for injection molding of ink jet nozzles, for example. As described above, according to the present invention, when machining a fine groove or the like, the work and the bite are fixed to the rotor supported by the hydrostatic bearing and can be exchanged, so that the setup change is easy and the number of steps is large. Processing can be performed with good precision and a small number of man-hours. Further, since the microscope is inside the mechanical device, even if an error occurs due to a setup change or the like, it can be corrected by measuring the workpiece with the microscope, and accurate machining can be performed.

[0065]

As described above, according to the present invention, the precision relative positioning of the cutting tool with respect to the work is configured to be performed precisely, and when the cutting tool is used continuously or intermittently, the temperature rises. It is possible to prevent the thermal expansion and contraction of the cutting tool from occurring on the cutting tool side, and prevent the precision relative positioning error from occurring.

[Brief description of drawings]

FIG. 1 is an overall external perspective view of an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a Y upper and lower table.

FIG. 3 is a sectional view of a coupling 300.

FIG. 4 is an enlarged perspective view of a coupling 300.

FIG. 5 (a) is a diagram showing a force acting on the coupling of the present invention. (B) It is a figure showing the force which acts on the conventional general coupling. (C) It is an external perspective view of a coupling.

FIG. 6 is a piping diagram of a Y upper / lower table 14.

FIG. 7 is a central sectional view of a main shaft.

FIG. 8 is an explanatory view of the attachment of the spindle.

FIG. 9 is a sectional view of a main shaft.

FIG. 10 is a plan view of the Z-cut table 4.

FIG. 11 is a sectional view of the Z-cut table 4.

FIG. 12 is a perspective view of an embodiment of a work holding unit.

13 is a cross-sectional view taken along the line EE of FIG.

FIG. 14 is a sectional view taken along the line FF of FIG.

FIG. 15 is a sectional view taken along the line GG in FIG.

FIG. 16A is a first modification of the holder. (B)
It is a 1st modification of a holder.

FIG. 17 (a) is a side view of the holder. (B) It is a top view of a holder.

18A to 18C are views showing how the holder is mounted.

FIG. 19 is a sectional view of a holder and a bearing portion.

FIG. 20 is a block diagram of the entire apparatus.

FIG. 21 is an overload detection circuit diagram connected to the bearing portion.

FIG. 22 is a diagram showing a mounting state of the microscope.

23 (a) and 23 (b) are views for explaining the machining order of the work.

FIG. 24 is an explanatory diagram of a processing order.

FIG. 25 through

FIG. 27 is a processing flow chart.

28 (a) and 28 (b) are views of a main part of a conventional cutting apparatus.

FIG. 29 is a completed state diagram of a work.

[Explanation of symbols]

 1 base, 3 X feed table, 4 Z cutting table, 7 main spindle body, 8 bit holder, 11 vertical microscope, 12 horizontal microscope, 14 Y vertical table, 18 hydraulic cylinder, 22 hydraulic cylinder, 22 ball screw nut, 25 notch hinge, 26 Aki mullator, 74 jersey, 36 oil tank, 37a, 37b air pad, 38-40 air pad, 41 holder shaft, 45 coupling plate, 46 coupling sheet, 57 oil groove, 61 shower box.

Claims (5)

[Claims] 1. A support structure for a cutting tool, comprising a cutting tool integrally provided on a rotary spindle for performing a cutting work on a workpiece by obtaining a rotational force, the structure being axially supported by a main body of a cutting machine. A supporting structure for a cutting tool, characterized in that cooling means for preventing the rotating main shaft from thermally expanding and contracting in the thrust direction is provided at the shaft supporting portion. 2. The rotating main shaft is supported by static pressure so that it can be inserted and removed in the radial direction and the thrust direction, and the cooling means is configured to send air to the static pressure supporting portion. The support structure for the cutting tool according to. 3. The rotating main shaft is directly engaged with an engaging portion formed at an end of an output shaft of an oil-cooled drive motor built in the main body to obtain the rotational force. The support structure for a cutting tool according to claim 2, wherein. 4. The cutting tool support structure according to claim 1, wherein the rotary spindle and the cutting tool are formed of a predetermined metal material having a small coefficient of thermal expansion. 5. The support structure for a cutting tool according to claim 1, wherein a hard surface treatment is applied to the support portion of the rotary spindle.