Wheel mount

Abstract

To provide a wheel mount that can simplify a work of attaching a grinding wheel.SOLUTION: A wheel mount that is fixed to a tip of a spindle and holds a grinding wheel for grinding a work piece, comprises a scroll chuck including: a disk including a first groove on an upper-surface side and a second groove on a lower-surface side; a screw that meshes with the first groove of the disk and rotates the disk; and a plurality of chuck claws that mesh with the second groove of the disk. The grinding wheel includes an annular base including a side surface, and a grinding stone provided on a lower-surface side of the base. When the screw is rotated, the disk rotates to move the plurality of the chuck claws along a radial direction of the disk, and the plurality of the chuck claws come into contact with the side surface of the base to hold the grinding wheel.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a wheel mount that holds a grinding wheel for grinding a workpiece. [Background technology]

[0002] A wafer on which a plurality of devices are formed is divided and diced to produce a plurality of device chips each including a device. A package substrate is obtained by mounting a plurality of device chips on a predetermined substrate and covering the mounted device chips with a sealing material (mold resin) made of resin. A plurality of package devices each including a plurality of packaged device chips are manufactured by dividing and dicing this package substrate. The device chips and package devices are incorporated into various electronic devices such as mobile phones and personal computers.

[0003] In recent years, with the trend toward smaller electronic devices, there is a demand for thinner device chips and packaged devices, so a process of thinning the wafer or package substrate before separation by grinding is sometimes carried out.

[0004] A grinding device is used to grind workpieces such as wafers and package substrates. The grinding device includes a chuck table that holds the workpiece and a grinding unit that performs grinding on the workpiece. The grinding unit includes a spindle that functions as a rotating shaft and a wheel mount fixed to the tip of the spindle, and an annular grinding wheel including a grinding wheel is attached to the wheel mount. The workpiece is held by the chuck table, and the grinding wheel is brought into contact with the workpiece while rotating the chuck table and the grinding wheel, thereby grinding the workpiece to thin it.

[0005] The grinding wheel is manually attached to the wheel mount by an operator. For example, the grinding wheel is attached to the wheel mount by inserting a bolt (screw) for attaching the wheel mount into a through hole formed in the wheel mount and screwing it into the grinding wheel (see Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2003-181767 A Summary of the Invention [Problem to be solved by the invention]

[0007] When mounting the grinding wheel to the wheel mount using bolts as described above, the operator must position the grinding wheel so that the through-holes formed in the wheel mount are aligned with the bolt holes formed in the grinding wheel, and then, while holding the grinding wheel in that position, insert the bolts into the through-holes and screw them into the bolt holes multiple times. Therefore, mounting the grinding wheel is time-consuming and labor-intensive.

[0008] In addition, the bolt may accidentally fall into the grinding device while the grinding wheel is being attached. In this case, the fallen bolt must be searched for and retrieved, which causes the grinding wheel attachment process to be delayed.

[0009] The present invention has been made in consideration of such problems, and has an object to provide a wheel mount that can simplify the installation work of a grinding wheel. [Means for solving the problem]

[0010] According to one aspect of the present invention, a wheel mount is fixed to a tip of a spindle and holds a grinding wheel for grinding a workpiece, the wheel mount comprising a scroll chuck including a disk including a first groove on an upper surface side and a second groove on a lower surface side, a screw that meshes with the first groove of the disk and rotates the disk, and a plurality of chuck jaws that mesh with the second groove of the disk, the grinding wheel comprising an annular base including a side surface, and a grinding wheel provided on the lower surface side of the base, and when the screw is rotated, the disk rotates and the plurality of chuck jaws move along the radial direction of the disk, and the plurality of chuck jaws come into contact with the side surface of the base to hold the grinding wheel. The disk includes a plurality of second grooves formed in an arc shape so that the distance from the center of the disk gradually changes, the number of the second grooves is the same as the number of the chuck jaws, and the plurality of second grooves are formed at intervals of an angle obtained by dividing 360° by the number of the chuck jaws in the circumferential direction of the disk. A wheel mount is provided.

[0011] In addition , good Preferably, the disk includes a plurality of the first grooves formed along a radial direction of the disk, and the screws are disposed along the radial direction of the disk and engage with the first grooves. Effect of the Invention

[0012] A wheel mount according to one aspect of the present invention includes a scroll chuck including a disk including a first groove and a second groove, a screw that engages with the first groove of the disk to rotate the disk, and a plurality of chuck jaws that engage with the second groove of the disk. When the screw is rotated, the disk rotates and the plurality of chuck jaws move along the radial direction of the disk, and the plurality of chuck jaws contact the side of a base to hold the grinding wheel.

[0013] The use of the wheel mount described above eliminates the need for the complicated process of fixing the grinding wheel to the wheel mount using bolts, thereby simplifying the installation process of the grinding wheel. [Brief description of the drawings]

[0014] [Figure 1] FIG. [Diagram 2]FIG. 2(A) is a bottom view showing the wheel mount, FIG. 2(B) is a cross-sectional view showing the cross-section of the wheel mount along line AA', and FIG. 2(C) is a cross-sectional view showing the cross-section of the wheel mount along line BB'. [Diagram 3] FIG. 4 is a cross-sectional view showing a portion of the base and the chuck jaws. [Figure 4] FIG. 4(A) is a plan view showing the upper surface side of the disk, and FIG. 4(B) is a bottom view showing the lower surface side of the disk. [Diagram 5] FIG. 5(A) is a perspective view showing the upper surface side of the grinding wheel, and FIG. 5(B) is a perspective view showing the lower surface side of the grinding wheel. [Figure 6] FIG. 2 is a perspective view showing a wheel mount and a grinding wheel. [Figure 7] FIG. 7(A) is a cross-sectional view showing a grinding wheel contacting a wheel mount, and FIG. 7(B) is a cross-sectional view showing a grinding wheel held by the wheel mount. [Figure 8] FIG. 8(A) is a bottom view showing the lower surface side of the disk including the arc-shaped groove, and FIG. 8(B) is a cross-sectional view showing a part of the disk including the arc-shaped groove and the chuck jaws. [Figure 9] 13 is a cross-sectional view showing a wheel mount and a grinding wheel according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. First, an example of the configuration of a grinding device equipped with a wheel mount according to this embodiment will be described. FIG. 1 is a perspective view showing a grinding device 2. In FIG. 1, the X-axis direction (first horizontal direction, front-back direction) and the Y-axis direction (second horizontal direction, left-right direction) are perpendicular to each other. Also, the Z-axis direction (grinding feed direction, vertical direction, up-down direction, height direction) is perpendicular to the X-axis direction and the Y-axis direction.

[0016] The grinding device 2 includes a base 4 that supports or houses each of the components that make up the grinding device 2. A rectangular opening 4a is provided on the top surface of the base 4, with the longitudinal direction aligned with the X-axis direction. An operation panel 6 is provided on the front end of the base 4 for inputting various information (processing conditions, etc.) to the grinding device 2. In addition, a rectangular parallelepiped support structure 8 that protrudes upward from the top surface of the base 4 is provided on the rear end of the base 4.

[0017] A ball screw type moving mechanism (moving unit) 10 is provided inside the opening 4a. A chuck table (holding table) 12 that holds a workpiece is connected to the moving mechanism 10. The moving mechanism 10 includes a table cover 10a that covers the periphery of the chuck table 12. In addition, bellows-shaped dustproof and drip-proof covers 14 that are expandable and contractible along the X-axis direction are provided in front and behind the table cover 10a so as to cover the components of the moving mechanism 10.

[0018] The upper surface of the chuck table 12 is a flat surface roughly parallel to the horizontal plane (XY plane) and constitutes a holding surface 12a that holds the workpiece. For example, the holding surface 12a is made of a porous material such as porous ceramics. The holding surface 12a is connected to a suction source (not shown) such as an ejector via a flow path (not shown), a valve (not shown), and the like formed inside the chuck table 12. When the suction force (negative pressure) of the suction source is applied to the holding surface 12a with the workpiece placed on the holding surface 12a, the workpiece is sucked and held by the chuck table 12.

[0019] The moving mechanism 10 moves the chuck table 12 together with the table cover 10a along the X-axis direction. In addition, a rotation drive source (not shown) such as a motor is connected to the chuck table 12, and this rotation drive source rotates the chuck table 12 around a rotation axis that is approximately parallel to the Z-axis direction.

[0020] A ball screw type moving mechanism (moving unit) 16 is provided on the front side of the support structure 8. The moving mechanism 16 includes a pair of guide rails 18 arranged along the Z-axis direction on the front side of the support structure 8. A flat moving plate 20 is attached to the pair of guide rails 18 in a state where it can slide along the guide rails 18.

[0021] A nut portion (not shown) is provided on the rear side (back side) of the moving plate 20, and a ball screw 22 disposed along the Z-axis direction between the pair of guide rails 18 is screwed into this nut portion. In addition, a pulse motor 24 is connected to an end of the ball screw 22. When the ball screw 22 is rotated by the pulse motor 24, the moving plate 20 moves in the Z-axis direction along the guide rails 18.

[0022] A holding member 26 is provided on the front side (surface side) of the moving plate 20, protruding forward from the front surface of the moving plate 20. The holding member 26 holds a grinding unit 28 that performs grinding on the workpiece held by the chuck table 12.

[0023] The grinding unit 28 includes a hollow cylindrical housing 30 held by the holding member 26. A cylindrical spindle (rotation shaft) 32 is accommodated in the housing 30 and arranged along the Z-axis direction. A tip end (lower end) of the spindle 32 protrudes downward from the lower end of the housing 30. A rotation drive source such as a motor that rotates the spindle 32 is connected to a base end (upper end) of the spindle 32.

[0024] A disk-shaped wheel mount 34 is fixed to the tip of the spindle 32. An annular grinding wheel 36 for grinding a workpiece is attached to the underside of the wheel mount 34.

[0025] The grinding device 2 grinds the workpiece. For example, the workpiece is a disk-shaped wafer made of a semiconductor material such as silicon, and has a front surface and a back surface that are generally parallel to each other. The wafer is divided into a plurality of rectangular regions by a plurality of streets (planned division lines) arranged in a lattice pattern so as to intersect with each other. In addition, on the front surface side of the wafer, devices such as ICs (Integrated Circuits), LSIs (Large Scale Integration), LEDs (Light Emitting Diodes), and MEMS (Micro Electro Mechanical Systems) devices are formed in each of the plurality of regions divided by the streets.

[0026] The wafer is divided along the streets to obtain a plurality of device chips each including a device. Before dividing the wafer, the back side of the wafer is ground and thinned by a grinding device 2 to obtain thinned device chips.

[0027] However, there are no limitations on the type, material, size, shape, structure, etc. of the workpiece. For example, the workpiece may be a substrate made of a semiconductor material other than silicon (GaAs, InP, GaN, SiC, etc.), glass, ceramics, resin, metal, etc. Furthermore, there are no limitations on the type, number, shape, structure, size, arrangement, etc. of devices formed on the workpiece, and the workpiece does not need to have any devices formed thereon. Furthermore, the workpiece may be a package substrate such as a CSP (Chip Size Package) substrate or a QFN (Quad Flat Non-leaded package) substrate.

[0028] When grinding a workpiece, first, the chuck table 12 is moved by the moving mechanism 10, and the workpiece held by suction on the chuck table 12 is positioned below the grinding wheel 36. Then, while the chuck table 12 and the spindle 32 are each rotated in a predetermined direction at a predetermined rotation speed, the grinding unit 28 is lowered by the moving mechanism 16, and the grinding wheel 36 is brought into contact with the workpiece. As a result, the upper surface side of the workpiece is scraped off by the grinding wheel 36, and the workpiece is thinned.

[0029] The grinding wheel 36 is detachably mounted on a wheel mount 34 fixed to the tip of the spindle 32. In this embodiment, a wheel mount 34 capable of holding the grinding wheel 36 is used. Fig. 2(A) is a bottom view showing the wheel mount 34. Fig. 2(B) is a cross-sectional view showing the cross section of the wheel mount 34 taken along line AA', and Fig. 2(C) is a cross-sectional view showing the cross section of the wheel mount 34 taken along line BB'.

[0030] The wheel mount 34 includes a disk-shaped base 40 made of metal or the like. The base 40 includes an upper surface (first surface) 40a and a lower surface (second surface) 40b that are generally parallel to each other, and a side surface (outer peripheral surface) 40c that is connected to the upper surface 40a and the lower surface 40b.

[0031] 2(A), a pair of protrusions 42 are provided on the lower surface 40b side of the outer periphery of the base 40. For example, the pair of protrusions 42 are formed in a rectangular shape when viewed from the bottom so as to protrude downward from the lower surface 40b, and are disposed so as to be spaced 180° apart in the circumferential direction of the base 40. As described later, the pair of protrusions 42 are used to align the wheel mount 34 and the grinding wheel 36.

[0032] Further, a pair of grinding fluid supply grooves 44 are provided on the lower surface 40b side of the base 40. For example, the pair of grinding fluid supply grooves 44 are formed in a semicircular arc shape along the outer periphery of the base 40 and are arranged so as to sandwich the pair of protrusions 42 therebetween.

[0033] 2(B), inside the base 40, there are provided a first grinding fluid supply passage 46 opening at the center of the upper surface 40a of the base 40, and a plurality of second grinding fluid supply passages 48 formed radially from the lower end of the first grinding fluid supply passage 46 along the radial direction of the base 40. The tip of the second grinding fluid supply passage 48 opens inside the grinding fluid supply groove 44.

[0034] 2(A), the wheel mount 34 includes a scroll chuck 50 that holds the grinding wheel 36. The scroll chuck 50 includes an annular disk (scroll plate, cam) 52, a screw 54 that rotates the disk 52, and a plurality of chuck jaws 56 connected to the disk 52.

[0035] For example, the disk 52 is built into the base 40. Specifically, an annular space corresponding to the shape of the disk 52 is provided inside the base 40, and the disk 52 is housed in this space. The disk 52 is disposed concentrically with the base 40, and the center position of the base 40 and the center position of the disk 52 generally coincide with each other.

[0036] 2(B) and 2(C), a first groove 52a is provided on the upper surface side of the disk 52, and a second groove 52b is provided on the lower surface side of the disk 52. The first groove 52a corresponds to an engagement portion (thread groove) that meshes with the screw 54. The second groove 52b corresponds to an engagement portion that meshes with the multiple chuck jaws 56.

[0037] 2(A) and 2(C), the base 40 is provided with a screw hole 40d formed from the side surface 40c of the base 40 toward the center, and a screw 54 is inserted into the screw hole 40d. A screw groove 54a is formed on the outer circumferential surface of the tip of the screw 54. When the screw 54 is inserted into the screw hole 40d, the first groove 52a of the disk 52 and the screw groove 54a of the screw 54 mesh with each other (see FIG. 2(C)).

[0038] 2(A) and 2(B), a plurality of openings 40e are provided on the lower surface 40b side of the base 40. The number of openings 40e is the same as the number of chuck jaws 56. For example, when three chuck jaws 56 are connected to the disk 52, three openings 40e are formed at intervals of 120° in the circumferential direction of the base 40.

[0039] The opening 40e is formed in a rectangular shape in a bottom view with its longitudinal direction aligned with the radial direction of the base 40. The opening 40e is provided in an area overlapping with the disk 52. The longitudinal length of the opening 40e is greater than the width (length from the outer peripheral surface to the inner peripheral surface) of the disk 52. Therefore, the lower surface side (second groove 52b side) of the disk 52 is exposed inside the opening 40e.

[0040] The chuck jaws 56 are inserted into the openings 40e, respectively. As shown in Fig. 2(B), the chuck jaws 56 include a support portion 58 that contacts the grinding wheel 36 (see Fig. 1) and supports the grinding wheel 36. The support portion 58 includes an upper surface (first surface) 58a and a lower surface 58b (second surface) that are generally parallel to each other, and a side surface (inclined surface) 58c that is connected to the upper surface 58a and the lower surface 58b.

[0041] The side surface 58c corresponds to a surface facing radially outward (side surface 40c side) of the base 40 among the multiple side surfaces included in the support portion 58. The side surface 58c is formed such that the lower surface 58b side is disposed radially outward of the base 40 relative to the upper surface 58a side, and is inclined with respect to the upper surface 58a and the lower surface 58b.

[0042] A connecting portion 60 that is connected to the chuck jaws 56 is provided on the upper surface 58a side of the support portion 58. For example, the connecting portion 60 is formed in a rectangular parallelepiped shape so as to protrude upward from the upper surface 58a of the support portion 58. A protrusion 60a is provided on the upper surface side of the connecting portion 60. When the connecting portion 60 is inserted into the opening 40e, the protrusion 60a of the connecting portion 60 is inserted into the second groove 52b of the disk 52, and the protrusion 60a and the second groove 52b mesh with each other.

[0043] FIG. 3 is a cross-sectional view showing a part of the base 40 and the chuck jaws 56. For example, the base 40 includes a pair of protruding parts 40f protruding from the inner wall of the opening 40e toward the inside of the opening 40e. The connecting part 60 of the chuck jaws 56 includes a pair of recessed parts 60b formed from the side surface of the connecting part 60 toward the inside. The chuck jaws 56 are attached to the base 40 so that the pair of protruding parts 40f are inserted into the pair of recessed parts 60b. In this way, the chuck jaws 56 are attached to the base 40, and the disk 52 and the chuck jaws 56 are kept engaged with each other. However, there is no limitation on the method of attaching the chuck jaws 56 to the base 40.

[0044] As shown in Figures 2(A) and 2(B), the length of the opening 40e in the longitudinal direction is greater than the length of the connecting portion 60 in the longitudinal direction. The length of the opening 40e in the short side direction (width direction) is approximately the same as the length of the connecting portion 60 in the short side direction (width direction). Therefore, the connecting portion 60 (chuck jaws 56) can slide along the radial direction of the base 40. On the other hand, the movement of the chuck jaws 56 (connecting portion 60) in the circumferential direction of the base 40 is limited by the inner wall of the opening 40e.

[0045] The scroll chuck 50 converts the rotational power of the screw 54 into the movement power of the chuck jaws 56 by the disk 52. Fig. 4(A) is a plan view showing the upper surface side of the disk 52, and Fig. 4(B) is a bottom view showing the lower surface side of the disk 52.

[0046] 4(A), for example, the disk 52 includes a plurality of first grooves 52a formed along the radial direction of the disk 52. Each of the plurality of first grooves 52a is formed linearly along the radial direction of the disk 52 so as to extend from the outer circumferential surface to the inner circumferential surface of the disk 52. The plurality of first grooves 52a are also arranged at approximately equal intervals along the circumferential direction of the disk 52.

[0047] The screw 54 connected to the disk 52 includes a plurality of screw grooves 54a formed along the length of the screw 54. The screw 54 is disposed along the radial direction of the disk 52 so that the screw grooves 54a mesh with the first grooves 52a. When the screw 54 is rotated, the disk 52 rotates about a rotation axis that is approximately perpendicular to the rotation axis of the screw 54. In other words, the disk 52 and the screw 54 form a cross-axis gear.

[0048] 4(B), for example, the disk 52 includes a second groove 52b formed in a spiral shape. The second groove 52b is formed in an annular shape such that the diameter gradually decreases from the outer circumferential surface side toward the inner circumferential surface side of the disk 52. The pitch of the second groove 52b in the radial direction of the disk 52 is approximately uniform.

[0049] The protrusions 60a (see FIG. 2B) of the chuck jaws 56 are formed to correspond to the pattern of the second grooves 52b in the radial direction of the disk 52. The chuck jaws 56 are coupled to the disk 52 such that the protrusions 60a mesh with the second grooves 52b.

[0050] When the disk 52 is rotated, the multiple chuck claws 56 slide along the second grooves 52b, and the disk 52 and the chuck claws 56 move relative to each other. The chuck claws 56 are fitted into the openings 40e (see FIGS. 2(A) and 2(B)), and the movement of the chuck claws 56 in the circumferential direction of the disk 52 is restricted. In the connection region between the disk 52 and the chuck claws 56, the positions of the second grooves 52b change along the radial direction of the disk 52. As a result, the chuck claws 56 move along the radial direction of the disk 52.

[0051] As described above, the scroll chuck 50 is mounted on the wheel mount 34. The wheel mount 34 holds the grinding wheel 36 by the scroll chuck 50. Fig. 5(A) is a perspective view showing the upper surface side of the grinding wheel 36, and Fig. 5(B) is a perspective view showing the lower surface side of the grinding wheel 36.

[0052] The grinding wheel 36 includes an annular base 70. The base 70 includes an upper surface (first surface) 70a and a lower surface (second surface) 70b that are generally parallel to each other, and a side surface (outer peripheral surface) 70c that is connected to the upper surface 70a and the lower surface 70b. An opening 70d that penetrates the base 70 from the upper surface 70a to the lower surface 70b is provided in the center of the base 70. The base 70 includes a side surface (inner peripheral surface) 70e that is exposed inside the opening 70d.

[0053] The opening 70d is formed in a truncated cone shape such that the diameter increases continuously from the upper surface 70a to the lower surface 70b. Therefore, the side surface 70e is inclined with respect to the upper surface 70a and the lower surface 70b so that the side surface 70e is positioned closer to the center of the base 70 as it approaches the upper surface 70a.

[0054] A pair of recesses 72 are provided on the upper surface 70a side of the base 70. The pair of recesses 72 are formed along the radial direction of the base 70 from the side surface 70c to the side surface 70e, and are arranged 180° apart in the circumferential direction of the base 70. As described below, the pair of recesses 72 are used to align the wheel mount 34 and the grinding wheel 36.

[0055] A plurality of grinding wheels 74 for grinding a workpiece are fixed to the lower surface 70b side of the base 70. For example, the grinding wheels 74 are formed in a rectangular parallelepiped shape and fixed to the base 70 by an adhesive or the like so as to be arranged at approximately equal intervals along the circumferential direction of the base 70.

[0056] The grinding wheel 74 is formed by fixing abrasive grains made of diamond, cBN (cubic boron nitride), etc., with a binder such as a metal bond, a resin bond, or a vitrified bond. However, there are no limitations on the material, shape, structure, size, etc. of the grinding wheel 74. In addition, the number and arrangement of the grinding wheels 74 can be changed as appropriate.

[0057] The base 70 is provided with a plurality of grinding fluid supply passages 76 that penetrate the base 70 from the upper surface 70a to the lower surface 70b. The plurality of grinding fluid supply passages 76 open at the upper surface 70a and the lower surface 70b, and are arranged at approximately equal intervals along the circumferential direction of the base 70. When the workpiece is ground by the grinding wheel 74, a liquid (grinding fluid) such as pure water is supplied to the grinding wheel 74 and the workpiece via the grinding fluid supply passages 76.

[0058] Next, a detailed description will be given of a procedure for mounting the grinding wheel 36 to the wheel mount 34. Fig. 6 is a perspective view showing the wheel mount 34 and the grinding wheel 36. Note that in Fig. 6, a part of the base 40 is not shown, and only the disk 52 and the screw 54 are shown.

[0059] First, the grinding wheel 36 is placed so that the lower surface 40b of the base 40 faces the upper surface 70a of the base 70, and the grinding wheel 36 is brought into contact with the wheel mount 34. This brings the lower surface 40b of the base 40 into contact with the upper surface 70a of the base 70. At this time, the positions of the multiple chuck jaws 56 are adjusted so that the lower surface sides of the chuck jaws 56 are inserted into the openings 70d of the base 70. The positions of the chuck jaws 56 can be adjusted by rotating the disk 52 with the screws 54 (see Figures 4(A) and 4(B)).

[0060] 7(A) is a cross-sectional view showing the grinding wheel 36 contacting the wheel mount 34. The grinding wheel 36 contacts the wheel mount 34 so that the lower surface side of the chuck jaws 56 is inserted into the opening 70d of the base 70. The orientation of the grinding wheel 36 is adjusted so that a pair of protrusions 42 provided on the base 40 are fitted into a pair of recesses 72 provided on the base 70. As a result, the grinding wheel 36 is disposed at a predetermined angle with respect to the wheel mount 34, and the wheel mount 34 and the grinding wheel 36 are aligned.

[0061] When the pair of protrusions 42 are fitted into the pair of recesses 72, the grinding fluid supply groove 44 provided in the base 40 and the grinding fluid supply path 76 provided in the base 70 are connected. This makes it possible for the grinding fluid that has flowed into the first grinding fluid supply path 46 to be supplied to the grinding wheel 74 via the second grinding fluid supply path 48, the grinding fluid supply groove 44, and the grinding fluid supply path 76.

[0062] Next, the disk 52 is rotated by rotating the screw 54 (see FIG. 4A), and the chuck jaws 56 are moved radially outward of the base 40 (see FIG. 4B). As a result, the base 70 is held by the chuck jaws 56.

[0063] 7(B) is a cross-sectional view showing the grinding wheel 36 held by the wheel mount 34. The chuck jaws 56 are formed so that the side surface 58c of the support portion 58 is generally parallel to the side surface 70e of the base 70. When the chuck jaws 56 are moved toward the side surface 70e of the base 70, the side surface 58c of the chuck jaws 56 comes into contact with the side surface 70e of the base 70, and the side surface 70e of the base 70 is supported by the multiple side surfaces 70e. As a result, the grinding wheel 36 is held by the multiple chuck jaws 56.

[0064] As described above, the grinding wheel 36 is attached to the wheel mount 34. Then, while rotating the grinding wheel 36, the grinding stone 74 is brought into contact with the workpiece held by the chuck table 12 (see FIG. 1), thereby grinding the workpiece.

[0065] During grinding of the workpiece, a liquid (grinding fluid) such as pure water is supplied to the first grinding fluid supply passage 46. The grinding fluid is then supplied to the grinding wheel 74 and the workpiece via the second grinding fluid supply passage 48, the grinding fluid supply groove 44, and the grinding fluid supply passage 76. This cools the grinding wheel 74 and the workpiece, and washes away chips (processing chips) generated by the grinding process.

[0066] When replacing the grinding wheel 36, the screw 54 (see FIG. 4(A) etc.) is rotated to rotate the disk 52 and move the multiple chuck jaws 56 toward the center of the base 40. This releases the grinding wheel 36 from the multiple chuck jaws 56, making it possible to remove the used grinding wheel 36 from the wheel mount 34.

[0067] As described above, the wheel mount 34 according to this embodiment includes the disk 52 including the first groove 52a and the second groove 52b, the screw 54 that meshes with the first groove 52a of the disk 52 to rotate the disk 52, and the scroll chuck 50 that includes the multiple chuck jaws 56 that mesh with the second groove 52b of the disk 52. When the screw 54 is rotated, the disk 52 rotates and the multiple chuck jaws 56 move along the radial direction of the disk 52, and the multiple chuck jaws 56 come into contact with the side surface 70e of the base 70 to hold the grinding wheel 36.

[0068] Use of the above-described wheel mount 34 eliminates the need for the troublesome task of using bolts to fix the grinding wheel 36 to the wheel mount 34. This simplifies the installation of the grinding wheel 36.

[0069] The configuration of the scroll chuck 50 mounted on the wheel mount 34 can be modified as appropriate as long as the chuck jaws 56 can be moved along the radial direction of the base 40. For example, the disk 52 may have an arc-shaped second groove formed therein instead of the spiral second groove 52b (see FIG. 4(B)).

[0070] 8(A) is a bottom view showing the lower surface side of the disk 52 including the arc-shaped second grooves 52c. For example, a plurality of arc-shaped second grooves 52c are formed on the lower surface side of the disk 52 along the circumferential direction of the disk 52. The number of the second grooves 52c is the same as the number of the chuck jaws 56. For example, when three chuck jaws 56 are connected to the disk 52, three second grooves 52c are formed at intervals of 120° in the circumferential direction of the disk 52.

[0071] Each of the second grooves 52c is formed in an arc shape with a gradually changing distance from the center O of the disk 52. Specifically, a distance d1 between one end of the second groove 52c and the center O is greater than a distance d2 between the other end of the second groove 52c and the center O.

[0072] 8B is a cross-sectional view showing a part of the disk 52 and the chuck jaw 56 including the arc-shaped second groove 52c. For example, a protrusion 60c that can be inserted into the second groove 52c of the chuck jaw 56 is provided on the upper surface side of the connecting portion 60 of the chuck jaw 56. The protrusion 60c may be integral with the connecting portion 60, or may be formed separately from the connecting portion 60 and then fixed to the connecting portion 60. The chuck jaw 56 is connected to the disk 52 so that the protrusion 60c is inserted into the second groove 52c (so that the protrusion 60c and the second groove 52c mesh with each other).

[0073] When the disk 52 is rotated, the multiple chuck claws 56 slide along the second grooves 52c, and the disk 52 and the chuck claws 56 move relatively to each other. The chuck claws 56 are fitted into the openings 40e (see FIGS. 2(A) and 2(B)), and the movement of the chuck claws 56 in the circumferential direction of the disk 52 is restricted. In the connection region between the disk 52 and the chuck claws 56, the positions of the second grooves 52c change along the radial direction of the disk 52. As a result, the chuck claws 56 move along the radial direction of the disk 52.

[0074] 7(A) and 7(B) illustrate an example in which the chuck jaws 56 support the side surface (inner peripheral surface) 70e of the base 70 of the grinding wheel 36, but the chuck jaws 56 may support other side surfaces of the base 70. For example, the chuck jaws 56 may support the base 70 inside a groove provided on the upper surface 70a side of the base 70.

[0075] Fig. 9 is a cross-sectional view showing a modified example of the wheel mount 34 and the grinding wheel 36. A plurality of grooves 70f that open on the upper surface 70a are provided on the upper surface 70a side of the outer periphery of the base 70 shown in Fig. 9.

[0076] The groove 70f is formed so that its width narrows toward the upper surface 70a of the base 70. Among the side surfaces (inner walls) exposed inside the groove 70f, a side surface (inner wall) 70g located on the center side of the base 70 is inclined with respect to the upper surface 70a and the lower surface 70b of the base 70.

[0077] 9 is mounted with a scroll chuck 50A. The scroll chuck 50A includes a disk 52A and a plurality of chuck jaws 56A. The chuck jaws 56A include a support portion 58A and a connecting portion 60A. Except for the points described below, the configurations of the scroll chuck 50A, disk 52A, chuck jaws 56A, support portion 58A, and connecting portion 60A are the same as those of the scroll chuck 50, disk 52, chuck jaws 56, support portion 58, and connecting portion 60 (see FIGS. 2(A) to 2(C), etc.).

[0078] The disk 52A is provided at a position corresponding to the groove 70f of the base 70. Then, a plurality of chuck jaws 56A are attached to the disk 52A. Among a plurality of side surfaces included in the support portion 58A of the chuck jaws 56A, a side surface (inclined surface) 58Aa facing the radially inner side of the base 40 (toward the center of the base 40) is inclined with respect to the upper and lower surfaces of the support portion 58A and is formed approximately parallel to the side surface 70g of the groove 70f.

[0079] When mounting the grinding wheel 36, first, the grinding wheel 36 is brought into contact with the wheel mount 34 so that the lower surface side of the chuck jaws 56A is inserted into the groove 70f of the base 70. Then, the disk 52A is rotated by rotating the screw 54 (see FIG. 4(A) etc.), and the multiple chuck jaws 56A are moved toward the center of the base 40. As a result, the side surface 58Aa of the chuck jaws 56 comes into contact with the side surface 70g of the base 70, and the side surface 70g of the base 70 is supported by the multiple side surfaces 58Aa. As a result, the base 70 is held by the multiple chuck jaws 56A.

[0080] In addition, the structures, methods, etc. according to the above-described embodiments can be modified as appropriate without departing from the scope of the object of the present invention. [Explanation of symbols]

[0081] 2 Grinding equipment 4 Foundation 4a aperture 6 Operation Panel 8 Support structure 10. Mobile mechanism (mobile unit) 10a Table cover 12 Chuck table 12a Holding surface 14 Dust-proof / water-proof cover 16 Mobile mechanism (mobile unit) 18 Guide rail 20 Moving Plate 22 Ball screw 24 Pulse motor 26 Retaining member 28 Grinding Unit 30 Housing 32 Spindle (rotating shaft) 34 Wheel mount 36 Grinding Wheel 40 Foundations 40a Top surface (1st surface) 40b Bottom surface (2nd surface) 40c Side (outer surface) 40d screw hole 40e aperture 40f Convex 42 Convex 44 Grinding fluid supply groove 46 First coolant supply passage 48 Second coolant supply passage 50,50A Scroll Chuck 52, 52A Disk (scroll plate, cam) 52a 1st groove 52b,52c 2nd groove 54 Screw 54a Thread groove 56,56A Chuck jaws 58,58A Support part 58a Top surface (first surface) 58b Bottom surface (2nd surface) 58c Side (slope) 58Aa Side (slope) 60,60A Connection 60a, 60c Convex part 60b Recess 70 Foundations 70a Top surface (1st surface) 70b Bottom surface (2nd surface) 70c Side (outer surface) 70d aperture 70e Side (inner surface) 70f groove 70g side (inner wall) 72 Recess 74 Grinding Wheel 76 Grinding fluid supply passage

Claims

1. A wheel mount fixed to a tip of a spindle and holding a grinding wheel for grinding a workpiece, comprising: a scroll chuck including a disk including a first groove on an upper surface side and a second groove on a lower surface side, a screw that engages with the first groove of the disk to rotate the disk, and a plurality of chuck jaws that engage with the second groove of the disk, The grinding wheel includes an annular base including a side surface, and a grinding wheel provided on a lower surface side of the base, When the screw is rotated, the disk rotates and the chuck jaws move along the radial direction of the disk, and the chuck jaws come into contact with the side surface of the base to hold the grinding wheel; the disk includes a plurality of the second grooves formed in an arc shape such that the distance from the center of the disk changes gradually; The second grooves are provided in the same number as the chuck jaws, A wheel mount characterized in that the second grooves are formed at intervals in the circumferential direction of the disk at an angle obtained by dividing 360° by the number.

2. the disk includes a plurality of the first grooves formed along a radial direction of the disk, 2. The wheel mount of claim 1, wherein the screw is disposed radially along the disc and engages with the first groove.

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