JP2001129743A - Rotational balance adjusting mechanism of cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotational balance adjusting mechanism of a cutting device capable of easily and finely adjusting the balance without using plural kinds of balance weights. SOLUTION: In this rotary balance adjusting mechanism of a cutting device comprising a spindle unit having a rotary spindle, a fixed flange having a tool mounting part on its outer periphery mounted on a point of the rotary spindle, an annular cutting tool having a mounting hole fittable to the tool mounting part of the fixed flange, and a holding flange for holding the cutting tool with the fixed flange, at least two threaded holes are radially formed on an outer periphery of the holding flange or the fixed flange, and screws for balance weight are movably fitted on the threaded holes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a rotational balance adjusting mechanism of a precision cutting device such as a dicing device.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, for example, the surface of a substantially disk-shaped semiconductor wafer is divided into a plurality of rectangular areas by cutting lines called streets arranged in a grid pattern. A predetermined circuit pattern is applied to each. In this way, a plurality of rectangular areas each having a circuit pattern are cut and separated individually to form a so-called semiconductor chip. The cutting of the semiconductor wafer is generally performed by a precision cutting device called a dicing device.

[0003] The above-described cutting apparatus includes a rotating spindle,
A fixed flange mounted on the tip of the rotary spindle and having a tool mounting portion on the outer periphery, an annular cutting tool having a mounting hole fitted to the tool mounting portion of the fixed flange, and holding the cutting tool with the fixed flange The cutting tool is rotated at a high speed (for example, 60000 rpm) to cut the workpiece. In particular, when cutting a semiconductor wafer, it is necessary to position a grindstone blade constituting a cutting tool having a thickness of about 15 μm on a cutting line having a width of about 50 μm formed on the semiconductor wafer and perform high-precision cutting. For this purpose, vibration of the blade must be avoided.

[0004] However, in order to facilitate the attachment and detachment of the cutting tool mounted on the rotary spindle, a small gap of about several μm is provided between the tool mounting portion of the fixed flange mounted on the rotary spindle and the mounting hole of the blade. It is necessary to provide. For this reason, if the rotation center of the rotary spindle and the rotation center of the cutting tool are mounted without being coincident with each other, the rotation balance cannot be maintained, and the rotation of the rotary spindle and the blades causes high-speed rotation to generate vibration. Due to this vibration, a lot of pitching occurs on both sides of a cutting groove cut by a grindstone blade constituting a cutting tool, and there is a problem that cutting cannot be performed with high accuracy. A similar problem also occurs when the rotation of the cutting tool itself is not balanced.

In order to solve the above-mentioned problem, the cutting device is provided with a rotation balance adjusting mechanism for adjusting the rotation balance after mounting the cutting tool on the rotary spindle. A conventionally used rotation balance adjustment mechanism includes a balance adjustment mechanism, which includes a clamping flange 03 for clamping a cutting tool 02 between the rotation spindle 01 and a fixed flange (not shown) attached to the tip of the rotation spindle 01 as shown in FIG. After a plurality of screw holes 04 for mounting weights for mounting are provided at equal intervals in the axial direction, and after the cutting tool 02 is mounted on the rotating spindle 01, a plurality of screw holes 0
4 different types of balance weight screws 0 with different weights
5 is screwed appropriately to adjust the rotational balance.

[0006]

In the above-described conventional rotational balance adjusting mechanism, in order to precisely adjust the rotational balance, a plurality of types of balance weight screws 05 having different weights are used. I have to prepare it. In addition, since the screw hole 04 and the balance weight screw 05 are small, handling them is troublesome, and considerable skill is required for balance adjustment.

[0007] The present invention has been made in view of the above-mentioned facts, and a main technical problem thereof is to provide a cutting device capable of easily performing precise balance adjustment without preparing a plurality of types of balance weight screws. It is to provide a rotation balance adjustment mechanism.

[0008]

According to the present invention, there is provided, in accordance with the present invention, a rotary spindle, a fixed flange mounted on a tip of the rotary spindle and having a tool mounting portion on an outer periphery, and the fixed flange. An annular cutting tool having a mounting hole to be fitted to the tool mounting portion, and a cutting device including a spindle unit having a clamping flange for clamping the cutting tool with the fixed flange. A spindle having at least two screw holes formed in a radial direction, a balance weight screw screwed into each of the screw holes, and advancing and retreating the balance weight screw appropriately in the radial direction along the screw hole; A rotational balance adjustment mechanism for a cutting device, wherein the rotational balance of the unit is adjusted.

According to the present invention, there is provided a rotary spindle, a fixed flange mounted on a tip of the rotary spindle and having a tool mounting portion on an outer periphery, and an annular hole having a mounting hole fitted to the tool mounting portion of the fixed flange. Cutting tool, and a cutting device provided with a spindle unit having a clamping flange for clamping the cutting tool with the fixed flange, at least two screw holes are formed in the outer periphery of the fixed flange in the radial direction, A balance weight screw is screwed into each of the screw holes, and the rotational balance of the spindle unit is adjusted by appropriately moving the balance weight screw in the radial direction along the screw hole. A rotational balance adjustment mechanism for a cutting device is provided.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of a rotation balance adjusting mechanism of a cutting device constituted according to the present invention will be described.
This will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view of a dicing apparatus which is a cutting apparatus equipped with a rotation balance adjusting mechanism constructed according to the present invention. The dicing apparatus shown in FIG. 1 includes a substantially rectangular parallelepiped device housing 10. In the apparatus housing 10, a stationary base 2 shown in FIG. 2 and a chuck table mechanism movably disposed on the stationary base 2 in a direction indicated by an arrow X which is a cutting feed direction and holding a workpiece. A spindle support mechanism 4 movably disposed on the stationary base 2 in a direction indicated by an arrow Y which is an indexing direction (a direction perpendicular to a direction indicated by an arrow X which is a cutting feed direction); A spindle unit 5 is provided in the mechanism 4 so as to be movable in a direction indicated by an arrow Z which is a cutting direction.

The chuck table mechanism 3 is provided on a stationary base 2 and fixed on the support base 31 by a plurality of mounting bolts 3a. The two guide rails 32, 3 provided
2 and a chuck table 33 disposed on the guide rails 32, 32 so as to be movable in a direction indicated by an arrow X. The chuck table 33 includes a guide rail 32,
The suction chuck support 33 movably disposed on the support 32
1 and a suction chuck 332 mounted on the suction chuck support 331.
A workpiece, for example, a disc-shaped semiconductor wafer is held by suction means (not shown).
The chuck table mechanism 3 includes a chuck table 3
There is provided a driving means 34 for moving 3 in the direction indicated by arrow X along the two guide rails 32,32.
The driving means 34 includes a male screw rod 341 disposed in parallel between the two guide rails 32, 32, and a driving source such as a pulse motor 342 for rotating the male screw rod 341. One end of the male screw rod 341 is rotatably supported by a bearing block 343 fixed to the support table 31, and the other end is power-coupled to the output shaft of the pulse motor 342 via a speed reducer (not shown). I have. The male screw rod 341 is screwed into a female screw hole (not shown) formed in a female screw block (not shown) provided on the lower surface of the central part of the suction chuck support 331 constituting the chuck table 33. Therefore, by driving the male screw rod 341 to rotate forward and reverse by the pulse motor 342, the chuck table 33 is moved in the direction indicated by the arrow X along the guide rails 32,32.

The spindle support mechanism 4 includes a stationary base 2
A support table 41 disposed thereon and fixed by a plurality of mounting bolts 4a, and two guide rails 42, 42 disposed on the support table 41 in parallel along a direction indicated by an arrow Y.
And a movable support base 43 disposed on the guide rails 42, 42 so as to be movable in a direction indicated by an arrow Y.
The movable support base 43 includes a movable support portion 431 movably disposed on the guide rails 42, 42 and a spindle mounting portion 432 attached to the movable support portion 431. A mounting bracket 433 is fixed to the spindle mounting portion 432.
33 is fastened to the moving support portion 431 by a plurality of mounting bolts 40a, so that the spindle mounting portion 432 is
Is attached to the movement support portion 431. The spindle mounting portion 432 is provided with two guide rails 432a and 432a extending in the direction indicated by the arrow Z on the surface opposite to the surface on which the mounting bracket 433 is mounted. The spindle support mechanism 4 includes a movable support base 43
Is provided in the direction indicated by the arrow Y along the two guide rails 42, 42. The driving means 44 includes a driving source such as a male screw rod 441 disposed in parallel between the two guide rails 42 and 42 and a pulse motor 442 for driving the male screw rod 441 to rotate. One end of the male screw rod 441 is rotatably supported by a bearing block (not shown) fixed to the support table 41, and the other end is power-coupled to the output shaft of the pulse motor 442 via a speed reducer (not shown). ing. The male screw rod 441 is screwed into a female screw hole (not shown) formed in a female screw block (not shown) protruding from the lower surface of the central part of the movable support part 431 constituting the movable support base 43. Accordingly, by driving the male screw rod 441 to rotate forward and reverse by the pulse motor 442, the movable support base 43 is moved in the direction indicated by the arrow Y along the guide rails 42,42.

The spindle unit 5 includes a movable base 5
1, a spindle holder 52 fixed to the moving base 51 by a plurality of mounting bolts 5a, and a spindle housing 53 mounted to the spindle holder 52.
Is provided. The movable base 51 is provided with two guided rails 51a, 51a which are slidably fitted to two guide rails 432a, 432a provided on the spindle mounting portion 432 of the spindle support mechanism 4. The guided rails 51a, 51a are connected to the guide rails 432.
a and 432a, it is movably supported in the direction indicated by arrow Z. The spindle housing 5
A cutting tool 54 is rotatably mounted on the distal end of 3. In the spindle housing 53, a rotation drive mechanism (not shown) for rotating and driving the cutting tool 54 is provided. The rotary spindle and the cutting tool 54 constituting the rotary drive mechanism and the mounting structure thereof will be described later in detail. Note that the spindle unit 5 is configured to move the moving base 51 to two guide rails 432a, 4
A drive means 55 is provided for moving in the direction indicated by arrow Z along 32a. The driving means 55 includes guide rails 432a and 432, similarly to the driving means 34 and 44.
2a, and a pulse motor 552 for rotationally driving the male screw rod (not shown).
The spindle unit 5 is driven by a pulse motor 552 to rotate the male screw rod (not shown) in the normal direction and the reverse direction.
It is moved in the direction indicated by arrow Z along 432a.

As shown in FIG. 1, the dicing apparatus shown in FIG. 1 includes a cassette 12 for stocking a semiconductor wafer 11 as a workpiece, a workpiece carrying-out means 13, a workpiece carrying means 14, a cleaning means 15, , A cleaning / transporting unit 16 and an alignment unit 17 including a microscope, a CCD camera, and the like. The semiconductor wafer 11 is
The cassette 1 is attached to the frame 111 by the tape 112, and the cassette 1 is attached to the frame 111.
2 housed. Further, the cassette 12 is placed on a cassette table 121 which is vertically movable by a lifting means (not shown). Next, the processing operation of the above dicing apparatus will be briefly described. The semiconductor wafer 11 mounted on a frame 111 housed at a predetermined position of a cassette 12 (hereinafter, referred to as a frame 111)
The semiconductor wafer 11 attached to the cassette wafer 121 is simply positioned at the carry-out position by vertically moving the cassette table 121 by a lifting means (not shown). Next, the workpiece unloading means 13 moves forward and backward, and the semiconductor wafer 11 positioned at the unloading position.
Is carried out to the workpiece mounting area 18. The semiconductor wafer 11 carried out to the workpiece mounting area 18 is moved by the turning operation of the workpiece transporting means 14 so that the suction chuck 33 of the chuck table 33 constituting the chuck table mechanism 3 is moved.
2 and is sucked and held by the suction chuck 332. The chuck table 33 holding the semiconductor wafer 11 by suction in this manner is moved along the guide rails 32 to just below the alignment means 17.
When the chuck table 33 is positioned immediately below the alignment unit 17, the alignment unit 17 detects a cutting line formed on the semiconductor wafer 11, and performs a precise alignment operation. Thereafter, the semiconductor wafer 11 held by the chuck table 33 is moved along a predetermined cutting line by the cutting tool 54 by moving the chuck table 33 holding the semiconductor wafer 11 by suction in a direction indicated by an arrow X which is a cutting feed direction. Be cut off. That is, the cutting tool 54 is mounted on the spindle unit 5 which is moved and adjusted in the direction indicated by the arrow Y which is the indexing direction and the direction indicated by the arrow Z which is the cutting direction, and is driven to rotate. Is moved along the lower side of the cutting tool 54 in the cutting feed direction, so that the semiconductor wafer 11 held on the chuck table 33 is cut along a predetermined cutting line by the cutting tool 54 and divided into semiconductor chips. . The divided semiconductor chips do not fall apart due to the action of the tape 112, and the state of the semiconductor wafer 11 mounted on the frame 111 is maintained. After the cutting of the semiconductor wafer 11 is completed in this manner, the chuck table 33 holding the semiconductor wafer 11 is returned to the position where the semiconductor wafer 11 is first suction-held, and
Here, the suction holding of the semiconductor wafer 11 is released. Next, the semiconductor wafer 11 is transported to the cleaning means 15 by the cleaning and transporting means 16, where it is cleaned. The semiconductor wafer 11 thus cleaned is carried out to the workpiece placing area 18 by the workpiece transporting means 14.
Then, the semiconductor wafer 11 is moved to the workpiece
Is stored in a predetermined position of the cassette 12.

Next, the rotary spindle and the cutting tool 54 constituting the spindle unit 5 and the mounting structure thereof will be described with reference to FIGS. FIG. 3 shows a perspective view of the rotary spindle 56 with the cutting tool 54 mounted thereon, and FIG. 4 shows a fixed flange 57 mounted on the rotary spindle 56 by a fastening nut 58.
, The cutting tool 54 and the clamping flange 59 are shown in an exploded manner, and FIG. 5 is an exploded view of a fixed flange 57 and a tightening nut 58 attached to the rotary spindle 56. As shown in FIG. 5, the illustrated rotary spindle 56 includes a mounting portion 560 for attaching a later-described fixing flange 57 to a distal end portion. This mounting portion 560
Has a flange portion 561, a tapered portion 562, and a cylindrical fastening portion 563. A male screw 563a is formed on the outer peripheral surface of the distal end portion of the tightening portion 563, and a tool fitting concave portion 563b for fitting a rotation stop tool is formed on the distal end surface.
Is provided. Attachment section 560 thus configured
The fixing flange 57 is attached to.

The fixed flange 57 has a flange portion 571 and a tool mounting portion 572. The tool mounting portion 572 is formed in a cylindrical shape, and has a male screw 5
72a are formed. A fitting hole 573 is formed at the center of the fixed flange 57 so as to penetrate in the axial direction. The fitting hole 573 is provided in the mounting portion 560.
Hole portion 5 corresponding to the outer peripheral surface of the tapered portion 562 of FIG.
73a and a cylindrical hole 573b corresponding to the outer peripheral surface of the fastening portion 563 of the mounting portion 560. The fixing flange 57 thus configured fits the tapered hole portion 573a of the fitting hole 573 into the tapered portion 562 of the mounting portion 560 and fits the cylindrical hole portion 573b into the fastening portion 563 of the mounting portion 560. After joining, the female screw 581 of the tightening nut 58 is screwed into the male screw 563a formed in the tightening portion 563 of the mounting portion 560, so that the female screw 581 is mounted on the mounting portion 560 of the rotary spindle 56 as shown in FIG. .

The cutting tool 54 is mounted on a fixed flange 57 mounted on the mounting portion 560 of the rotary spindle 56. The cutting tool 54 includes a blade support member 541 and an annular grindstone blade 542 provided on the outer periphery of the blade support member 541. Blade support member 54
1 has a mounting hole 541 in the center thereof which is larger than the outer dimensions of the tool mounting portion 572 of the fixing flange 57 by about several μm.
a. The cutting tool 54 thus configured
The fitting hole 541a of the blade support member 541 is fitted to the tool mounting portion 572 of the fixed flange 57, and the female screw 591 formed on the holding flange 59 is then fitted to the tool mounting portion 57.
By being screwed into the screw 572a formed in FIG. 2, it is clamped and mounted by the flange portion 571 of the fixed flange 57 and the clamping flange 59 as shown in FIG.

In the illustrated embodiment, the holding flange 59 is provided with a rotation balance adjusting mechanism configured according to the present invention. One embodiment of the rotation balance adjusting mechanism will be described with reference to FIGS. The holding flange 59 in the illustrated embodiment is formed of aluminum in an annular shape, and three screw holes 592a, 592b, 592c are formed in the outer periphery in the radial direction. These three screw holes 592a, 592b, 59
2c are provided at equal intervals with a phase angle of 120 degrees from each other. A balance weight screw 60 is screwed into each of the three screw holes 592a, 592b, 592c formed in the holding flange 59. This balance weight screw 60 has screw holes 592a, 592b,
A male screw 61 screwed to 592c is formed, and an engagement groove 62 for engaging a driver is provided on one end surface thereof. The balance weight screw 60 is desirably made of a metal having a large specific gravity, such as stainless steel, tungsten, or copper, or an alloy thereof. The balance weight screw 60 configured as described above is provided with three screw holes 5 formed in the holding flange 59.
92a, 592b and 592c, respectively. The balance weight screw 60 screwed into the screw holes 592a, 592b, 592c engages a driver in the engagement groove 62 and turns left and right to rotate the screw holes 592a, 592b, 5
It is possible to move back and forth in the radial direction along 92c, and to change the radial distance from the center of rotation. Since the centrifugal force of the balance weight screw 60 is proportional to the radial distance from the center of rotation, the balance weight screw 60
The rotational balance can be adjusted by adjusting the position in the radial direction. As described above, in the embodiment shown in FIGS. 6 and 7, the balance weight screw 60 is screwed into the three screw holes 592a, 592b, 592c formed in the holding flange 59, and the balance weight screw 60 is formed. The rotational balance can be adjusted by advancing and retreating in the radial direction along the screw holes 592a, 592b, 592c, so that even one type of balance weight screw 60 can be precisely adjusted, and the adjustment work is also possible. It becomes very easy. It is important that the balance weight screw 60 is held at the adjusted position.
It is desirable to use a screw in which a synthetic resin such as nylon is fused to one part to increase the loosening prevention function.

Next, another embodiment of the rotation balance adjusting mechanism will be described with reference to FIG. The rotation balance adjusting mechanism in the embodiment shown in FIG.
7, three screw holes 571a on the outer periphery of the flange portion 571,
571b and 571c are formed at regular intervals with a different phase angle of 120 degrees from each other in the radial direction, and these three screw holes 571a,
The balance weight screw 60 described above is screwed to each of 571b and 571c. Therefore, also in the embodiment shown in FIG. 8, the rotational balance can be adjusted by advancing and retreating the balance weight screw 60 in the radial direction along the screw holes 571a, 571b, 571c. The same operation and effect as in the embodiment can be obtained.

As described above, in the embodiment shown in FIGS. 6, 7 and 8, the holding flange 59 and the fixing flange 5
7, three screw holes 592a on the outer periphery of the flange portion 571,
592b, 592c and 571a, 571b, 571
c are formed at equal intervals in the radial direction with a phase angle of 120 degrees to each other, and these three screw holes 592a, 592b, 592 are formed.
Although an example is shown in which the balance weight screws 60 and 60 are screwed to c and 571a, 571b, and 571c, respectively, at least two screw holes may be provided, and the phase angles need not be equal to each other. When there are two screw holes, it is necessary that the two screw holes are provided with a phase angle other than 180 degrees.

Next, an example of rotational balance adjustment by the rotational balance adjusting mechanism in the embodiment shown in FIGS. 6 and 7 will be described. In order to adjust the rotation balance of the spindle unit as the rotating body, it is necessary to detect the unbalance position of the spindle unit as the rotating body. As a device for detecting an unbalance position of a rotating body, for example, a product name “Program Auto Balancer (MYS)” manufactured and sold by Omiya Kogyo Co., Ltd., located at 5-60 Daimon-cho, Fukuyama City, Hiroshima Prefecture.
ELF-1) "can be used. When the unbalance of the spindle unit as a rotating body is detected by using such an unbalance detection device, the display means of the unbalance detection device displays the holding flange 59 as shown in FIG.
Of one of the screw holes 592 provided in, for example, the screw hole 592a
It is displayed that an unbalance exists at an unbalance position at an angle θ ₀ (unbalance angle) in the rotation direction indicated by the arrow with reference to.

When the unbalance position is detected with reference to the screw hole 592a provided in the holding flange 59 as described above, the balance weight screw 60 screwed into the screw holes 592a, 592b, 592c is moved forward and backward. This will correct the imbalance, and an example of this correction method will be described below. As shown in FIG.
Assuming that the centrifugal force at the unbalanced position at the angle θ ₀ from 2a is P1, the centrifugal force P1 is expressed by Expression 1.

[0024]

## EQU1 ## P1 = m₀・ R₀・ Ω²  Where m₀Is the unbalanced mass, r₀Is unbalanced quality
Radius where quantity exists, ω is angular velocity

Next, the balance weight screw 60 screwed into the reference screw hole 592a is moved in the radial direction, for example, in the outer peripheral direction by Δr, and the unbalance detector is used to rotate the spindle unit as a rotating body in the same manner as described above. Detect imbalance. In this case, since the balance weight screw 60 has been moved by Δr in the outer peripheral direction, the unbalun position is at the angle θ.
Displaced position of the angle theta ₁ from the reference screw hole 592a in the range of _0. Here, if the centrifugal force at the position of the reference screw hole 592a increased by moving the balance weight screw 60 screwed into the reference screw hole 592a by Δr in the outer circumferential direction is set to P2, the increased centrifugal force P2 is expressed by the following equation (2). It is represented by

[0026]

P2 = m · Δr · ω²  Where m is the weight of the balance weight screw 60

From the above unbalance angles θ ₀ and θ ₁ and the above formulas 1 and 2, formula 3 for obtaining the unbalance amount (m ₀ · r ₀ ) of the spindle unit as a rotating body is obtained.

[0028]

P2 · sin θ ₁ = P1 · sin (θ ₀ −θ ₁ ) m · Δr · ω ² · sin θ ₁ = m ₀ · r ₀ · ω ² · si
n (θ ₀ −θ ₁ ) m ₀ · r ₀ = m · Δr · ω ² · sin θ ₁ / ω ² · si
n (θ ₀ −θ ₁ ) m ₀ · r ₀ = m · Δr · sin θ ₁ / sin (θ ₀ −θ
₁ )

The screw holes 592a and 592a are used to cancel the unbalance amount (m ₀ · r ₀ ) obtained by the above equation (3).
The imbalance is corrected by moving and adjusting the balance weight screw 60 screwed to 592b, 592c in the center direction or the outer peripheral direction. Here, screw holes 592a, 592b, 59 are used to correct the imbalance.
The amount of movement when the balance weight screw 60 screwed to 2c is moved forward and backward will be described. The unbalance amount (m ₀ · r ₀ ) obtained by the above equation 3 acts on the unbalance position at an angle θ ₀ from the reference screw hole 592a, and the X axis of the unbalance amount (m ₀ · r ₀ ) The direction component Xa is represented by Expression 4.

[0030]

Xa = (m ₀ · r ₀ ) sin θ ₀

Further, Y of the unbalance amount (m ₀ · r ₀ )
The axial component Ya is represented by Expression 5.

[0032]

## EQU5 ## Ya = (m ₀ · r ₀ ) cos θ ₀

To cancel the component Xa in the X-axis direction of the unbalance amount (m ₀ · r ₀ ), the screw hole 592b or 59
What is necessary is just to move the balance weight screw 60 screwed in 2c or the screw holes 592b and 592c in the radial direction. Here, the balance weight screw 60 screwed into the screw hole 592b is moved, and the amount of movement is R
If it is 2, the movement amount R2 is represented by Expression 6.

[0034]

[6] _{m · R2 · sinθ + (m} 0 · r 0) sinθ 0 = 0 R2 = - (m 0 · r 0) sinθ 0 / (m · sinθ) R2 = -Δr · sinθ 1 · sinθ 0 / { sin (θ
₀₋ θ ₁ ) · sin θ｝ where θ is the angle between the screw hole 592 a and the screw hole 592 b, and 120 degrees in the illustrated embodiment.

On the other hand, the unbalance amount (m ₀ · r ₀ )
In order to cancel the component Ya in the Y-axis direction, the balance weight screw diameter 60 screwed into the screw hole 592a may be moved in the radial direction. Assuming that the movement amount of the balance weight screw 60 screwed into the screw hole 592a is R1, the movement amount R1 is expressed by Expression 7.

[0036]

[Mathematical formula 7] m · R1 + (m ₀ · r ₀ ) cos θ ₀ + m · R
2 cos θ = 0 R1 + Δr · sin θ ₁ · cos θ ₀ / sin (θ ₀ −
θ ₁ ) + R2 · cos θ = 0 R1 = − ｛Δr · sin θ ₁ · cos θ ₀ / sin (θ
₀₋ θ ₁ ) + Δr · sin θ ₁ · sin θ ₀ · cos
θ｝ / ｛sin (θ ₀ −θ ₁ ) · sin θ｝ R1 = −Δr · sin θ ₁ ｛cos θ ₀ · sin θ + s
inθ ₀ · cos θ｝ / ｛sin (θ ₀ −θ ₁ ) · si
nθ｝

As described above, in the illustrated embodiment, the balance weight screw 60 screwed into the screw hole 592b is shifted in the center direction by R2 (if the obtained value is minus (-), the center direction is determined. Value is plus (+)
In the outer circumferential direction), the balance weight screw 60 screwed into the screw hole 592a is shifted from the initial position by R1 in the center direction (if the obtained value is minus (-), the center direction; The imbalance can be corrected by moving in a direction toward the outer circumference when the obtained value is plus (+). As described above, the imbalance can be corrected by moving the two balance weight screws 60.

Next, another embodiment of the rotation balance adjusting mechanism will be described with reference to FIG. The rotation balance adjustment mechanism in the embodiment shown in FIG. 10 shows an example in which the rotation balance adjustment mechanism is applied to the holding flange 59, and two screw holes 592a and 592b formed in the radial direction have a phase of 90 degrees in the rotation direction shown by the arrow. The two threaded holes 592a and 592b are provided with screws 60 for balance weight.
Is screwed. When the angle θ between the screw holes 592a and 592b is set to 90 degrees as in the rotation balance adjustment mechanism shown in FIG. 10, sin θ is 1, and cos
Since θ is 0, Expression 6 for calculating the movement amount R2 is expressed by Expression 8, and R2 is a movement amount that cancels out only the X-axis direction component.

[0039]

R2 = −Δr · sin θ ₁ · sin θ ₀ / si
n (θ ₀ -θ ₁ )

Equation 7 for calculating the movement amount R1 is represented by Expression 9, and this R1 is a movement amount for canceling only the Y-axis direction component.

[0041]

R1 = −Δr · sin θ ₁ · cos θ ₀ / si
n (θ ₀ -θ ₁ )

As described above, the two balance weight screws 60
The method for correcting the imbalance by moving back and forth is described above. However, the above formulas 6 and 7 or the formulas 8 and 9 for obtaining the movement amounts R2 and R1 of the balance weight screw 60 are previously stored in the memory of the unbalance detection device. By storing them and inputting Δr and θ, the movement amounts R2 and R1 can be displayed on the display means of the unbalance detection device. Then, the operator can easily correct the imbalance by moving the balance weight screw 60 forward and backward according to the displayed movement amounts R2 and R1.

Although the present invention has been described based on the illustrated embodiment, the present invention is not limited to the embodiment. For example, in the illustrated embodiment, an example is shown in which three screw holes and two screw holes are provided in the holding flange 59 and the fixing flange 57, but it is sufficient that at least two screw holes are provided. When two screw holes are used, the angle formed by the two screw holes must be set to an angle other than 180 degrees, and this angle is preferably 90 degrees. In the illustrated embodiment, an example in which the present invention is applied to a dicing device has been described. However, the present invention is not limited to this, and can be widely applied to other cutting devices other than the dicing device. .

[0044]

The rotation balance adjusting mechanism of the cutting device according to the present invention is constructed as described above, and has the following effects.

That is, according to the present invention, at least two dies are provided on the outer periphery of the holding flange for holding the cutting tool with the fixed flange.
The screw holes for the balance weight are screwed into the screw holes, respectively, and the screw for the balance weight is appropriately advanced and retracted in the radial direction along the screw hole to rotate the spindle unit. The balance can be adjusted. Accordingly, precise adjustment of even one type of balance weight screw is possible, and the adjustment work is extremely simple, so that even inexperienced persons can easily carry out rotational balance adjustment.

According to the present invention, at least two screw holes are formed in the outer periphery of the fixed flange in the radial direction.
A screw for balance weight is screwed into each of the screw holes, and the rotational balance of the spindle unit is adjusted by appropriately moving the screw for balance weight in the radial direction along the screw hole. As with the present invention, the balance weight screw can be precisely adjusted even with one kind of screw, and has an operational effect such that the adjustment work becomes easy.

[Brief description of the drawings]

FIG. 1 is a perspective view of a dicing device, which is a cutting device equipped with a rotation balance adjusting mechanism configured according to the present invention.

FIG. 2 is a perspective view of a main part of the dicing apparatus shown in FIG.

FIG. 3 is a perspective view of a main part of a spindle unit included in the dicing apparatus shown in FIG. 2;

FIG. 4 is an exploded perspective view showing a fixed flange, a cutting tool, and a holding flange attached to a rotary spindle included in the spindle unit shown in FIG. 3 by a fastening nut;

5 is an exploded perspective view showing a fixing flange and a tightening nut attached to a rotary spindle constituting the spindle unit shown in FIG. 3;

FIG. 6 is an exploded perspective view showing one embodiment of a rotation balance adjusting mechanism configured according to the present invention.

FIG. 7 is a front view showing a part of a holding flange provided with the rotation balance adjusting mechanism shown in FIG.

FIG. 8 is an exploded perspective view showing another embodiment of the rotation balance adjusting mechanism configured according to the present invention.

FIG. 9 is an explanatory diagram of unbalance adjustment by a rotation balance adjustment mechanism configured according to the present invention.

FIG. 10 is a partially cutaway front view showing still another embodiment of the rotation balance adjusting mechanism configured according to the present invention.

FIG. 11 is an exploded perspective view showing a rotation balance adjustment mechanism of a conventionally used cutting device.

[Explanation of symbols]

 2: Stationary base 3: Chuck table mechanism 31: Support table of chuck table mechanism 32: Guide rail of chuck table mechanism 33: Chuck table of chuck table mechanism 34: Drive means of chuck table mechanism 4: Spindle support mechanism 41: Chuck Table mechanism support 42: Guide rail of chuck table mechanism 43: Movable support base of chuck table mechanism 431: Moving support of movable support base 432: Spindle mounting section of movable support base 44: Driving of chuck table mechanism Means 5: Spindle unit 510: Moving base of spindle unit 520: Spindle holder of spindle unit 53: Spindle housing of spindle unit 54: Cutting tool 541: Blade support member of cutting tool 542: Grinding wheel blade of cutting tool 55: Spindle unit driving means 56: Rotating spindle 57: Fixed flange 571a, 571b, 571c: Screw hole 58: Tightening nut 59: Nipping flange 592a, 592b, 592c: Screw hole 10: Device housing 11: Semiconductor wafer 12: Cassette 13: Workpiece unloading means 14: Workpiece transfer means 15: Cleaning means 16: Cleaning transfer means 17: Alignment means 60: Screw for balance weight

Claims (2)

[Claims] An annular cutting tool having a rotary spindle, a fixed flange mounted on a tip of the rotary spindle and having a tool mounting portion on an outer periphery, and a mounting hole fitted to a tool mounting portion of the fixed flange; In a cutting device provided with a spindle unit having a clamping flange for clamping a cutting tool with the fixed flange, at least two screw holes are formed in the outer periphery of the clamping flange in a radial direction, and each of the screw holes has a screw hole. Adjusting the rotation balance of the spindle unit by appropriately moving the balance weight screw in the radial direction along the screw hole to adjust the rotation balance of the spindle unit. mechanism. An annular cutting tool having a rotary spindle, a fixed flange mounted on a tip of the rotary spindle and having a tool mounting portion on an outer periphery, and a mounting hole fitted to the tool mounting portion of the fixed flange; A cutting device comprising a spindle unit having a clamping flange for clamping a cutting tool with the fixed flange, wherein at least two screw holes are formed in the outer circumference of the fixed flange in a radial direction, and each of the screw holes has a screw hole. Adjusting the rotation balance of the spindle unit by appropriately moving the balance weight screw in the radial direction along the screw hole to adjust the rotation balance of the spindle unit. mechanism.