CUTTING DEVICE

Abstract

Cutting device comprising: a clamping table for holding a workpiece; a pair of first and second cutting units for cutting the workpiece held on the clamping table, wherein both the first and second cutting units have a spindle and a cutting blade attached to the spindle; and a blade changing device for changing the cutting blade attached to the spindle of the first cutting unit and for changing the cutting blade attached to the spindle of the second cutting unit, the blade changing device includes: a nut attachment and removal unit for attaching and removing a nut for securing the cutting blade to the spindle in both the first and second cutting units, and a blade attachment and removal unit for attaching the cutting blade to the spindle in both the first and second cutting units and for removing the cutting blade from the spindle in both the first and second cutting units, the nut attachment and removal unit includes: a swivel shaft a first nut turning section attached to one end of the rotating shaft for holding and turning the nut to attach the cutting blade to the spindle of the first cutting unit, a second nut turning section attached to the other end of the rotating shaft for holding and turning the nut to attach the cutting blade to the spindle of the second cutting unit, an engine, and A power transmission unit connected to the motor and the rotating shaft for transferring the power of the motor to the rotating shaft in order to rotate the rotating shaft.

Description

Technical area

[0001] The present invention relates to a cutting device for cutting a workpiece. Description of related technology

[0002] In a component chip manufacturing process, a wafer with multiple components on the front side is used. That is, the front side of the wafer is divided by multiple intersecting dividing lines (streets) to define multiple separate regions in which multiple components, such as integrated circuits (ICs) and large-scale integration (LSI) circuits, are respectively formed. By dividing the wafer along the dividing lines, multiple component chips comprising the multiple components can be obtained.

[0003] For example, a cutting device is used to divide the wafer. The cutting device includes a chuck table for holding the wafer and a cutting unit for cutting the wafer held on the chuck table. The cutting unit includes a spindle (rotating shaft) and an annular cutting blade attached to the spindle for cutting the wafer. The cutting blade is fixed to the front end portion of the spindle using a nut. By rotating the cutting blade attached to the spindle of the cutting unit and feeding the cutting unit toward the chuck table, the wafer is cut and divided by the cutting blade. There is a case where what is called a facing-double-type cutting device with a pair of cutting units is used to cut the wafer. In the facing-double-type cutting device, cutting blades are arranged opposite each other.The use of such a facing-double-type cutting device allows two types of cutting operations with different cutting conditions to be performed simultaneously. The cutting conditions include the type of cutting blade and the depth of a cut in the wafer.

[0004] The cutting blade wears out during wafer cutting and is therefore replaced periodically. When replacing the cutting blade, the nut securing the (old) cutting blade is first loosened and removed. After that, the cutting blade is removed from the spindle. After that, a new cutting blade is attached to the front end portion of the spindle and then secured by the nut. If such a cutting blade replacement operation is performed manually, time and effort are consumed. Furthermore, in this case, there is a possibility that an operator might accidentally drop the cutting blade or the nut during the operation. To address this problem, attempts have been made to automate this cutting blade replacement operation. Japanese Patent Application Laid-Open No.2007-229843 discloses a blade changing device provided in a facing double-type cutting device, which is configured to automatically perform the cutting blade changing operation. This blade changing device includes a mechanism (blade attaching and detaching unit) for attaching and detaching the cutting blade and a mechanism (nut attaching and detaching unit) for attaching and detaching the nut for fixing the cutting blade to the front end portion of the spindle. PRESENTATION OF THE INVENTION

[0005] The blade changing device provided in the facing double-type cutting device includes a pair of nut rotating sections corresponding to each pair of cutting units. The nut securing the cutting blade mounted in one of the two cutting units is held and rotated by one of the two nut rotating sections, and the nut securing the cutting blade mounted in the other cutting unit is held and rotated by the other nut rotating section. Furthermore, a pair of motors are connected to the pair of nut rotating sections to rotate them. However, each motor for rotating each nut rotating section is large in size and weight. Accordingly, the size and weight of the blade changing device increase in the configuration in which the pair of motors are connected to the pair of nut rotating sections.Furthermore, when designing and operating such a blade changing device, several motors must be prepared and therefore maintenance is required, which causes an increase in costs.

[0006] It is therefore an object of the present invention to provide a cutting device having a blade changing device that can be reduced in size, weight or cost.

[0007] According to one aspect of the present invention, a cutting device is provided, comprising: a clamping table for holding a workpiece, a pair of first and second cutting units for cutting the workpiece held on the clamping table, each of the first and second cutting units having a spindle and a cutting blade attached to the spindle, and a blade changing device for changing the cutting blade attached to the spindle of the first cutting unit and for changing the cutting blade attached to the spindle of the second cutting unit, the blade changing device comprising: a nut attaching and detaching unit for attaching and detaching a nut for fixing the cutting blade to the spindle in each of the first and second cutting units,and a blade attachment and detachment unit for attaching the cutting blade to the spindle in both the first and second cutting units and for detaching the cutting blade from the spindle in both the first and second cutting units, the nut attachment and detachment unit comprising: a rotary shaft, a first nut rotating portion attached to one end of the rotary shaft for holding and rotating the nut for fixing the cutting blade to the spindle of the first cutting unit, a second nut rotating portion attached to the other end of the rotary shaft for holding and rotating the nut for fixing the cutting blade to the spindle of the second cutting unit, a motor, and a power transmission unit connected to the motor and the rotary shaft for transmitting the power of the motor to the rotary shaft to thereby rotate the rotary shaft.

[0008] Preferably, the rotational axis of the first nut rotating section is aligned with the rotational axis of the second nut rotating section. Preferably, the power transmission unit comprises a speed reduction device for making the rotational speed of the rotating shaft lower than the rotational speed of the motor, thereby making the torque of both the first nut rotating section and the second nut rotating section greater than the torque of the motor.

[0009] More preferably, the speed reduction device comprises a bevel gear or a hypoid gear.

[0010] The cutting device of the present invention includes the blade changing device for changing the cutting blade. The blade changing device includes the motor, the rotating shaft, the first nut rotating portion fixed to one end of the rotating shaft, the second nut rotating portion fixed to the other end of the rotating shaft, and the power transmission unit for transmitting the power of the motor to the rotating shaft. The blade changing device can transmit the power of the motor to the first nut rotating portion and the second nut rotating portion through the power transmission unit and the rotating shaft. That is, the two nut rotating portions can be driven by a single motor. Accordingly, it is not necessary to provide separate motors for the first nut rotating portion and the second nut rotating portion, so the size, weight, or cost of the blade changing device can be reduced.

[0011] The above and other objects, features and advantages of the present invention and the mode for carrying them out will become more apparent and the invention itself will be best understood by studying the following description and the appended claims with reference to the attached drawings which show a preferred embodiment of the invention. SHORT DESCRIPTION OF THE FIGURES Fig. 1 is a perspective view illustrating a cutting device; Fig. 2 is a perspective view illustrating a cutting unit; Fig. 3 is a perspective view showing an attaching and detaching unit; Fig. 4 is a perspective view illustrating a power transmission unit; and Fig. 5 is a perspective view showing the interior of the power transmission unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0012] Now, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. First, a cutting device 2 according to this preferred embodiment will be described with reference to Fig. 1 are described. Fig. 1 is a perspective view of the cutting device 2.

[0013] As in Fig. 1, the cutting device 2 includes a base housing 4 for supporting various components of the cutting device 2. A rectangular opening 4a is formed on the upper surface of the base housing 4 at a left front corner portion thereof. A cassette support table 6 is provided in the rectangular opening 4a so as to be vertically movable by a lifting mechanism (not shown). A cassette 8 is adapted to be attached to the upper surface of the cassette support table 6. The cassette 8 is capable of storing a plurality of workpieces 11. In Fig. 1, the outline of the cassette 8 is shown by a dashed line.

[0014] Each workpiece 11 is a disk-shaped wafer formed from a semiconductor such as silicon.

[0015] A plurality of intersecting dividing lines (streets) are formed on the front side of the workpiece 11 to thereby define a plurality of separated regions in which a plurality of components, such as ICs and microelectromechanical system devices (MEMSs), are formed. By using the cutting device 2 to cut the workpiece 11 along the dividing lines, the workpiece 11 can be divided into a plurality of component chips including the plurality of components. A circular adhesive tape 13 is attached to the rear side of the workpiece 11. The adhesive tape 13 has a diameter larger than that of the workpiece 11. The adhesive tape is formed of, for example, a plastic. The workpiece 11 is positioned at a central portion of the adhesive tape 13. An annular frame 15 having a circular central opening is attached to a peripheral portion of the adhesive tape 13.The central opening of the frame 15 has a diameter larger than that of the workpiece 11. Accordingly, the workpiece 11 is supported by the frame 15 by the adhesive tape 13 in such a manner that the workpiece 11 is disposed in the central opening of the frame 15. In this way, the workpiece 11 supported by the frame 15 by the adhesive tape 13 is stored in the cassette 8. The workpiece 11 is not limited in terms of material, shape, structure, size, etc. For example, the workpiece 11 could be a wafer formed of any semiconductors other than silicon. Further, the wafer could be formed of any other materials, such as ceramics, plastics, and metals. Furthermore, the components formed on the workpiece 11 are not limited in terms of type, number, shape, structure, size, shape, etc. Furthermore, the workpiece 11 could have no components.Furthermore, the workpiece 11 may not be supported by the frame 15. Furthermore, the adhesive tape 13 may not be attached to the workpiece 11.

[0016] A rectangular opening 4b is formed on the upper surface of the base case 4, to the right of the rectangular opening 4a. The rectangular opening 4b is elongated in the X direction (longitudinal direction or work feed direction) indicated by an arrow X. A ball screw-type moving mechanism 10 and a dustproof cover 12 for partially covering the upper side of the moving mechanism 10 are provided within the rectangular opening 4b. The moving mechanism 10 includes a ball screw mechanism (not shown) and a movable table 10a configured to be moved in the X direction by the ball screw mechanism.

[0017] A chuck table (holding table) 14 for holding the workpiece 11 is provided on the movable table 10a. The chuck table 14 is connected to a rotation drive source (not shown) such as a motor, so that the chuck table 14 is rotatable about a vertical axis extending in the Z direction (vertical direction or cutting feed direction) indicated by an arrow Z. The chuck table 14 is movable in the X direction by an operation of the moving mechanism 10 (machining feed operation). The chuck table 14 has an upper surface as a holding surface 14a for holding the workpiece 11. The holding surface 14a is connected to a vacuum source (not shown) through a suction duct (not shown). This suction duct is formed inside the chuck table 14. A plurality of clamps 16 for clamping the frame 15 supporting the workpiece 11 are provided on the outer circumference of the clamping table 14.The frame 15 is clamped so that it is held by the clamps 16.

[0018] A pair of parallel guide rails 18 are provided above the opening 4b so as to extend in the Y direction (lateral direction or index direction) indicated by an arrow Y. The guide rails 18 are movable toward and away from each other in the X direction. Each guide rail 18 has an L-shaped cross section in such a manner that it has a horizontal surface for supporting the frame 15 thereon and a vertical surface perpendicular to the horizontal surface. The guide rails 18 are arranged such that the respective vertical surfaces are opposite each other in the X direction.The guide rails 18 correspond to a temporary placement area for temporarily arranging the workpiece 11 and act to support the frame 15 supporting the workpiece 11 in such a manner that the outer periphery of the frame 15 is brought into contact with the vertical surfaces of the guide rails 18 in the X direction. Thus, the workpiece 11 supported by the frame 15 is placed at a predetermined position by the guide rails 18 (positioning operation).

[0019] A double-column-like first support structure 20 is provided on the upper surface of the base housing 4 so as to span the opening 4b. A rail 22 is attached to the front surface of the first support structure 20 (on the side where the guide rails 18 are located) so as to extend in the Y direction. A holding unit 26 is connected to the rail 22 by a moving mechanism 24.

[0020] The holding unit 26 is configured to come into contact with the upper surface of the frame 15, thereby holding the frame 15 under suction. The moving mechanism 24 acts to move the holding unit 26 vertically and also to move the holding unit 26 in the Y direction along the rail 22. The holding unit 26 acts to hold the frame 15 under suction in the state in which the workpiece 11 supported by the frame 15 is positioned by the guide rails 18, and next, transfers the workpiece 11 to the chuck table 14. The holding unit 26 includes a handling mechanism 26a for handling the frame 15 supporting the workpiece 11. The handling mechanism 26a is provided at the left end of the holding unit 26 (on the side where the opening 4a is present). The handling mechanism 26a is configured to hold (grip) the frame 15.That is, the frame 15 supporting the workpiece 11 stored in the cassette 8 is held by the handling mechanism 26a, and the holding unit 26 is next moved in the Y direction, thereby transferring the workpiece 11 from the cassette 8 to the guide rails 18 before cutting. Conversely, the frame 15 supporting the workpiece 11 arranged on the guide rails 18 is held by the handling mechanism 26a, and the holding unit 26 is next moved in the Y direction, thereby transferring the workpiece 11 from the guide rails 18 to the cassette 8 after cutting.

[0021] Furthermore, a rail 28 is attached to the front surface of the first support structure 20 so as to extend in the Y direction. A holding unit 32 is connected to the rail 28 by a moving mechanism 30. The holding unit 32 is configured to come into contact with the upper surface of the frame 15 and thereby hold the frame 15 under suction. The moving mechanism 30 acts to move the holding unit 32 vertically and also to move the holding unit 32 along the rail 28 in the Y direction.

[0022] A second double-column-type support structure 34 is arranged on the upper surface of the base case 4 behind the first support structure 20 so as to span the opening 4b. A pair of moving mechanisms 36a and 36b are fixed to the front surface of the second support structure 34 (on the side where the first support structure 20 is present) at a pair of column portions thereof. A cutting unit 38a (first cutting unit) is provided at the lower end of the moving mechanism 36a, and a cutting unit 38b (second cutting unit) is provided at the lower end of the moving mechanism 36b. The moving mechanism 36a serves to move the cutting unit 38a in the Y direction and the Z direction, thereby adjusting the Y position and the Z position of the cutting unit 38a in the Y direction and the Z direction, respectively.Similarly, the moving mechanism 36b serves to move the cutting unit 38b in the Y direction and the Z direction, thereby adjusting the Y position and the Z position of the cutting unit 38b in the Y direction and the Z direction, respectively.

[0023] Fig. 2 is a perspective view showing the cutting unit 38a. As shown in Fig. 2, the cutting unit 38a includes a hollow cylindrical housing 70. A fixed cylindrical spindle (rotary shaft) 72 is rotatably supported in the housing 70. A front end portion (one end portion) of the spindle 72 protrudes from the housing 70 so as to be exposed. An attachment 74 is fixed to this front end portion of the spindle 72. The attachment 74 is circular in a side view. A rotation drive source (not shown) such as a motor is connected to a base end portion (the other end portion) of the spindle 72 to rotate the spindle 72.

[0024] The attachment 74 includes a disk-shaped flange portion 76 and a fixed cylindrical support shaft 78 projecting from the front surface 76a of the flange portion 76 at a central portion thereof. An annular projection 76b is formed on the front surface 76a of the flange portion 76 at a peripheral portion thereof. The front end portion of the projection 76b is substantially parallel to the front surface 76a of the flange portion 76. A threaded portion 78a is formed on the outer peripheral surface of the support shaft 78. A recess 78b is formed on the front end surface of the support shaft 78 at a central portion thereof. An annular cutting blade 80 for cutting the workpiece 11 is attached to the support shaft 78 of the attachment.

[0025] The cutting blade 80 includes an annular base 82 and an annular cutting edge 84 formed along the outer periphery of the base 82. The base 82 includes a circular central hole 82a. An annular projection 82b is formed around the opening 82a of the base 82 so as to protrude from the front surface of the base 82. The projection 82b of the base 82 serves as a gripping portion to be gripped when attaching or detaching the cutting blade 80, as described below. The cutting edge 84 is formed by bonding abrasive grains, such as diamond abrasive grains, with a nickel plating layer as a binder. However, the abrasive grains and the binder for forming the cutting edge 84 are not limited and can be appropriately selected, for example, according to the material of the workpiece 11 and details regarding cutting.

[0026] An annular nut 86 for securing the cutting blade 80 is screwed onto the threaded portion 78a of the support shaft 78. The nut 86 has a circular central opening 86a with a diameter corresponding to the diameter of the support shaft 78. The opening 86a of the nut 86 has an internal thread corresponding to the threaded portion 78a of the support shaft 78. That is, the internal thread of the opening 86a of the nut 86 is configured to engage the threaded portion 78a of the support shaft 78. Furthermore, the nut 86 has a plurality of through holes 86b (e.g., four through holes, as shown) extending in the axial direction of the nut 86 (along the thickness of the nut 86). The through holes 86b are arranged along the outer circumference of the nut 86 at substantially equal intervals.

[0027] The cutting blade 80 is attached to the spindle 72 in the following manner. First, the cutting blade 80 is attached to the attachment 74 in such a manner that the support shaft 78 of the attachment 74 is inserted through the opening 82a of the base 82 of the cutting blade 80. Thereafter, the nut 86 is screw-engaged with the threaded portion 78a of the support shaft 78 until the nut 86 is screwed in. Accordingly, the base 82 of the cutting blade 80 is securely held between the nut 86 and the front end surface of the projection 76b of the flange portion 76 of the attachment 74. In this way, the cutting blade 80 is attached to the front end portion of the spindle 72.

[0028] While the cutting unit 38a with reference to Fig. 2, the configuration of the cutting unit 38b is similar to that of the cutting unit 38a. The cutting blade 80 mounted in the cutting unit 38a and the cutting blade 80 mounted in the cutting unit 38b are arranged opposite each other in the Y direction. Although not shown, each of the cutting units 38a and 38b is provided with a nozzle for supplying a cutting fluid such as clean water to the workpiece 11 and the cutting blade 80.

[0029] As in Fig. 1, an imaging unit (camera) 40 for imaging the workpiece 11 held on the chuck table 14 is provided adjacent to the cutting unit 38a. Similarly, another imaging unit 40 is provided adjacent to the cutting unit 38b. An image obtained by the imaging unit 40 for the cutting unit 38a is used in alignment between the workpiece 11 held on the chuck table 14 and the cutting unit 38a. Similarly, an image obtained by the imaging unit 40 for the cutting unit 38b is used in alignment between the workpiece 11 and the cutting unit 38b.

[0030] The workpiece 11 is cut by operating the cutting units 38a and 38b in the following manner. The workpiece 11 is placed on the chuck table 14 by the adhesive tape 13, and the frame 15 is fixed by the clamps 16. In this state, a vacuum generated by the vacuum source is applied to the holding surface 14a of the chuck table 14, thereby holding the workpiece 11 to the holding surface 14a by the adhesive tape 13 under suction. Thereafter, each cutting blade 80 is rotated and fed to cut the workpiece 11 while supplying cutting fluid toward the workpiece 11. In this way, the workpiece 11 is cut by each cutting blade 80.

[0031] A cleaning unit 42 for cleaning the workpiece 11 cut by each cutting blade 80 is provided on the right side of the opening 4b (on the side opposite the opening 4a). The cleaning unit 42 includes a rotary table 44 for holding the workpiece 11 in a cylindrical cleaning space defined in the base case 4. A rotation drive source (not shown) is connected to the lower end of the rotary table 44 to rotate the rotary table 44 at a predetermined speed. A nozzle 46 for spraying a cleaning fluid toward the workpiece 11 held on the rotary table 44 is provided above the rotary table 44. For example, the cleaning fluid is a mixed fluid obtained by mixing water and air. The workpiece 11 is cleaned by operating the cleaning unit 42 in the following manner.The workpiece 11 is first held under suction on the rotary table 44 and fluid is sprayed from the nozzle 46 towards the workpiece 11 in order to thereby clean the workpiece 11.

[0032] In this way, the workpiece 11 cut by the cutting units 38a and 38b is transferred to the cleaning unit 42 by operation of the holding unit 32 and then cleaned by the cleaning unit 42. Thereafter, the workpiece 11 is held by the holding unit 26 under suction and transferred to the guide rails 18. After positioning the workpiece 11 by operation of the guide rails 18, the frame 15 supporting the workpiece 11 is gripped by the handling mechanism 26a of the holding unit 26, and then the workpiece 11 is stored in the cassette 8 by operation of the holding unit 26.

[0033] A blade changing device (blade changing mechanism) 50 is provided on the rear side of the second support structure 34 (on the side opposite the side on which the first support structure 20 is provided). The blade changing device 50 serves to change the cutting blade 80 (see Fig. 2) and also to change the cutting blade 80 mounted on the spindle 72 of the cutting unit 38b. The blade changing device 50 includes a pair of blade holders 52a and 52b for supporting and storing a plurality of cutting blades 80. The blade holders 52a and 52b are arranged opposite each other in the Y direction.

[0034] The blade holder 52a includes a cylindrical support shaft 54a extending in the Y direction and a disc-shaped member 56a attached to the front end of the support shaft 54a. Similarly, the blade holder 52b includes a cylindrical support shaft 54b extending in the Y direction and a disc-shaped member 56b attached to the front end of the support shaft 54b. The support shaft 54a is connected to a rotary drive source (not shown), such as a motor, so that the support shaft 54a is rotatable about its horizontal axis extending in the Y direction. Similarly, the support shaft 54b is connected to a rotary drive source (not shown), such as a motor, so that the support shaft 54b is rotatable about its horizontal axis extending in the Y direction.A plurality of cutting blades 80 are stored on the front side of the disc-shaped member 56a (on the side where the blade holder 52b is present), and a plurality of cutting blades 80 are similarly stored on the front side of the disc-shaped member 56b (on the side where the blade holder 52a is present). For example, in . Fig. 1, six cutting blades 80 are stored on the disc-shaped member 56a so as to be arranged at substantially equal intervals along the outer periphery of the disc-shaped member 56a. Similarly, six cutting blades 80 are stored on the disc-shaped member 56b so as to be arranged at substantially equal intervals along the outer periphery of the disc-shaped member 56b. The plurality of cutting blades 80 stored on the disc-shaped member 56a are respectively arranged opposite the plurality of cutting blades 80 stored on the disc-shaped member 56a.

[0035] A plate-shaped base 58 is provided in an area defined between the blade holders 52a and 52b. The base 58 is attached to a fastening element (not shown) provided behind the second support structure 34. The base 58 is substantially parallel to a horizontal plane (i.e., an XY plane defined by the X-direction and the Y-direction). A movement mechanism 60 is attached to the lower surface of the base 58.

[0036] The moving mechanism 60 includes a ball screw 62 rotatably supported on the lower surface of the base 58. A movable member 64 is screw-engaged with the ball screw 62. The movable member 64 has a shape like a rectangular prism. A support member 66 is fixed to the lower surface of the movable member 64. The support member 66 has a substantially C-shaped configuration in a side view. The support member 66 serves to support an attachment and detachment unit (attachment and detachment mechanism) 68 for attaching and detaching the cutting blade 80 and the nut 86 (see Fig. 2). A pulse motor (not shown) for rotating the ball screw 62 is connected to one end of the ball screw 62. When the ball screw 62 is rotated by this pulse motor, the movable member 64 is moved in the X direction, and the attachment and detachment unit 68 supported by the support member 66 fixed to the movable member 64 is accordingly moved along the ball screw 62 in the X direction. With this configuration, the X position of the attachment and detachment unit 68 can be controlled in the X direction.

[0037] Fig. 3 is a perspective view illustrating the attachment and detachment unit 68. The support member 66 supporting the attachment and detachment unit 68 includes a plate-shaped upper wall portion 66a fixed to the lower surface of the movable member 64 so as to extend horizontally in the X direction, a plate-shaped side wall portion 66b projecting downward from the lower surface of the upper wall portion 66a at its rear end portion, and a plate-shaped support portion 66c projecting from the front surface of the side wall portion 66b at its lower end portion. That is, the support portion 66c is substantially parallel to the upper wall portion 66a. The attachment and detachment unit 68 is supported by the support portion 66c of the support member 66.

[0038] The attachment and removal unit 68 has a nut attachment and removal unit 100 for attaching and removing the nut 86 (see Fig. 2) for attaching the cutting blade 80 to the spindle 72, and a blade attachment and detachment unit 140 for attaching the (new) cutting blade 80 to the spindle 72 and detaching the (old) cutting blade 80 from the spindle 72. Both the nut attachment and detachment unit 100 and the blade attachment and detachment unit 140 are attached to the upper surface of the support portion 66c of the support member 66.

[0039] The nut attachment and removal unit 100 includes a motor 102 as a rotational drive source and a power transmission unit (power transmission mechanism) 104 connected to the motor 102. The motor 102 and the power transmission unit 104 are arranged side by side in the X direction. The motor 102 includes a hollow cubic housing 102a for storing components such as a rotor and a stator, and a rotation shaft (output shaft) 102b (see Fig. 4) connected to the rotor so as to extend in the Z direction. An upper end portion of the rotary shaft 102b protrudes from the upper surface of the housing 102a, and a disc-shaped roller member (drive pulley) 102c is fixed to this upper end portion of the rotary shaft 102b. When electric power is supplied to the motor 102, the rotary shaft 102b and the roller member 102c are rotated together about a vertical axis extending in the Z direction.

[0040] The power transmission unit 104 includes a hollow cubic housing 104a and a rotary shaft 104b stored in the housing 104a so as to extend in the Z direction. An upper end portion of the rotary shaft 104b protrudes from the upper surface of the housing 104a, and a disc-shaped roller element (drive pulley) 104c is fixed to this upper end portion of the rotary shaft 104b. The housing 104a has a central through-hole 104d extending in the Y direction, and a rotary shaft 106 is inserted through the through-hole 104d of the housing 104a. That is, opposite end portions of the rotary shaft 106 protrude from the right and left side surfaces of the housing 104a. Fig. The rotary shaft 106 shown in Figure 3 is formed from a single cylindrical shaft. The rotary shaft 106 is supported by the housing 104a so as to be rotatable about a horizontal axis extending in the Y direction. The rotary shaft 106 is connected to the rotary shaft 104b in the housing 104a. A connecting mechanism for connecting the rotary shaft 104b and the rotary shaft 106 will be described in detail below.

[0041] The motor 102 and the power transmission unit 104 are connected to each other by an endless connecting member 108, such as a belt and a chain. The connecting member 108 is guided between the roller member 102c of the motor 102 and the roller member 104c of the power transmission unit 104 in such a manner that it comes into contact with the outer peripheral surface of the roller member 102c and the outer peripheral surface of the roller member 104c. That is, the connecting member 108 is guided between the roller members 102c and 104c so that it forms an oval shape in a plan view. Thus, the roller member 102c, the roller member 104c, and the connecting member 108 form a roller mechanism. When electric power is supplied to the motor 102, the rotary shaft 102b of the motor 102 is rotated.Accordingly, a rotational drive force generated by the motor 102 is transmitted to the rotary shaft 104b through the roller member 102c, the connecting member 108, and the roller member 104c, so that the rotary shaft 104b is rotated about its vertical axis extending in the Z direction. Then, the rotational force of the rotary shaft 104b is transmitted to the rotary shaft 106 through a gear (to be described below), so that the rotary shaft 106 is rotated about its horizontal axis extending in the Y direction. In this way, the power of the motor 102 is transmitted to the rotary shaft 106 through the power transmission unit 104.

[0042] A nut rotating section (nut rotating unit) 110a is attached to one end (left end) of the rotating shaft 106. The nut rotating section 110a serves to rotate the nut 86 (see Fig. 2) and rotate to fix the cutting blade 80 to the spindle 72 of the cutting unit 38a. Similarly, a nut rotating portion (nut rotating unit) 110b is fixed to the other end (right end) of the rotating shaft 106. The nut rotating portion 110b serves to hold the nut 86 and rotate to fix the cutting blade 80 to the spindle 72 of the cutting unit 38b. Accordingly, when the rotating shaft 106 is rotated, the nut rotating portions 110a and 110b are rotated about their respective horizontal axes extending in the Y-axis direction together with the rotating shaft 106. The rotation axis of the nut rotating portion 110a is aligned with the rotation axis of the nut rotating portion 110b in the axial direction of the rotating shaft 106.

[0043] The nut rotation sections 110a and 110b each have a cylindrical rotary member 112 attached to one end of the rotary shaft 106. The rotary member 112 is normally biased by a spring or the like toward the side opposite the power transmission unit 104, and when an external force is applied to the rotary member 112 in its axial direction, the rotary member 112 is movable in the Y direction against the biasing force of the spring. The rotary member 112 has a front surface 112a facing the side opposite the side where the power transmission unit 104 is present.

[0044] The rotary member 112 has four retaining pins 114 projecting from the front surface 112a. The four retaining pins 114 are adapted to be inserted into respective ones of the four through holes 86b of the nut 86 (see Fig. 2). That is, the four retaining pins 114 are formed to correspond to the positions and sizes of the four through-holes 86b. The four retaining pins 114 have the same diameter, which is substantially the same as the diameter of each through-hole 86b. While four retaining pins 114 are formed in this preferred embodiment, a plurality of retaining pins 114, each corresponding to the plurality of through-holes 86b, may be formed in the present embodiment; the number of the plurality of through-holes 86b may be appropriately determined.

[0045] Furthermore, a plurality of gripping elements 116 for gripping the nut 86 are provided on the outer circumference of the rotary member 112 so as to be arranged at substantially equal intervals along the outer circumference of the rotary member 112. Each gripping element 116 is a rod-shaped element extending substantially along the rotary member 112, and a base end portion (one end) of each gripping element 116 is fixed to the outer circumferential surface of the rotary member 112. Fig. In the preferred embodiment shown in Fig. 3, the four gripping members 116 are fixed to the rotary member 112. A front end portion (the other end) of each gripping member 116 protrudes from the front surface 112a of the rotary member 112, and a claw portion 116a is formed at this front end portion of each gripping member 116 so as to be inclined toward the center line (axis) of the rotary member 112. Further, the gripping member 116 is normally biased in the radial direction of the rotary member 112 by a spring or the like, so that each claw portion 116a is movable in the radial direction of the rotary member 112.

[0046] A hollow cylindrical cover 118 is provided around the rotary member 112 to surround the outer peripheral surface of the rotary member 112. A part of the rotary member 112 and the base end portion of each gripping member 116 are stored in the cover 118. When the rotary member 112 is pressed toward the cover 118 by applying an external force in the axial direction, the rotary member 112 and the plurality of gripping members 116 are inserted into the cover 118 against the biasing force of the spring.

[0047] When the rotary member 112 is pressed into the cover 118 as mentioned above, the front end portion of each gripping member 116 comes into contact with the inner wall of the cover 118 to be pressed by the inner wall of the cover 118 against the urging force of the spring. Accordingly, the claw portion 116a formed at the front end portion of each gripping member 116 is moved inward in the radial direction of the rotary member 112. Consequently, each gripping member 116 extends in the axial direction of the rotary member 112 along the inner wall of the cover 118 (closed state). In this closed state, the claw portion 116a of each gripping member 116 is positioned radially inward of the outer peripheral edge of the rotary member 112 in the radial direction of the rotary member 112.Conversely, when the external force applied to the rotating member 112 is removed, the rotating member 112 is moved axially out of the cover 118 by the urging force of the spring, so that the pushed-in state of the front end portion of each gripping member 116 by the inner wall of the cover 118 is released. Consequently, the front end portion of each gripping member 116 is moved outward in the radial direction of the rotating member 112 by the urging force of the spring. Accordingly, each gripping member 116 extends in a direction different from the axial direction of the rotating member 112 (open state). In this open state, the claw portion 116a of each gripping member 116 is positioned radially outward from the outer peripheral edge of the rotating member 112 in the radial direction of the rotating member 112. The other nut rotating portion 110b has the same configuration as that of the nut rotating portion 110a.

[0048] Each of the nut rotating sections 110a and 110b serves to hold and rotate the nut 86. The nut 86 is rotated by the nut rotating section 110a in the manner described below. The operation of the nut rotating section 110b is similar to the operation of the nut rotating section 110a, and the description of the operation of the nut rotating section 110b is therefore omitted. First, the nut 86 is brought into contact with the front surface 112a of the rotating member 112 such that the plurality of holding pins 114 of the rotating member 112 fit into a respective one of the plurality of through holes 86b (see Fig. 2) the nut 86 can be inserted. Thereafter, the rotary member 112 is pressed into the cover 118, so that the plurality of gripping members 116 come into the closed state, and the claw portions 116a accordingly come into contact with the outer peripheral surface of the nut 86, thereby gripping the nut 86. In this state, with the nut 86 held by the plurality of gripping members 116, the motor 102 is actuated. Consequently, the torque of the motor 102 is transmitted to the rotary shaft 106 through the power transmission unit 104, thereby rotating the rotary shaft 106. Accordingly, the rotary member 112 fixed to the rotary shaft 106 is rotated, so that the nut 86 held by the gripping members 116 fixed to the rotary member 112 is rotated. In this way, the nut 86 can be held and rotated by the nut rotating portion 110a.That is, the nut 86 can be automatically attached and detached by operation of the nut attachment and detachment unit 100 when changing the cutting blade mounted in the cutting unit 38a. Similarly, the nut 86 can be held and rotated by the nut rotating section 110b. Accordingly, the nut 86 can be automatically attached and detached by operation of the nut attachment and detachment unit 100 when changing the cutting blade 80 mounted in the cutting unit 38b. The specific operation of the nut attachment and detachment unit 100 when changing the cutting blade 80 will be described in detail below.

[0049] As described above, the torque of the motor 102 is transmitted to the rotating shaft 106 through the power transmission unit 104. Specifically, the power transmission unit 104 includes a mechanism for transmitting the torque of the rotating shaft 104b to the rotating shaft 106, thereby rotating the rotating shaft 106. Fig. 4 is a perspective view illustrating the power transmission unit 104, and Fig. 5 is a perspective view showing the interior of the power transmission unit 104. In Fig. 5, the housing 104a of the power transmission unit 104 is not shown.

[0050] As in Fig. 4 and Fig. As shown in Figure 5, the power transmission unit 104 includes an annular first bearing 120 and an annular second bearing 122 for rotatably supporting the rotary shaft 106 in the housing 104a. The first bearing 120 is fixed to surround the rotary shaft 106 at a portion on the left side where the nut rotating portion 110a is present. The second bearing 122 is fixed to surround the rotary shaft 106 at a portion on the right side where the nut rotating portion 110b is present.

[0051] Furthermore, the power transmission unit 104 has a gear unit 124 for converting the torque of the rotary shaft 104b into the torque of the rotary shaft 106. The gear unit 124 is configured from a first gear 126 fixed to the rotary shaft 104b and a second gear 128 fixed to the rotary shaft 106. Accordingly, the gear unit 124 is configured to convert the torque about the vertical axis into the torque about the horizontal axis. The first gear 126 is connected to the lower end of the rotary shaft 104b (see Fig. 3) so that the rotational axis of the first gear 126 extends in the Z direction. A toothed portion 126a is formed at the lower end portion of the first gear 126. On the other hand, the second gear 128 has an annular shape and is connected to the rotary shaft 106 so as to surround it at a portion between the first bearing 120 and the second bearing 122. A toothed portion 128a is formed on a side surface of the second gear 128 opposite the second bearing 122. The toothed portion 128a of the second gear 128 meshes with the toothed portion 126a of the first gear 126. The other side surface of the second gear 128 opposite the first bearing 120 serves as a support surface 128b for supporting the first bearing 120.

[0052] The first gear 126 and the second gear 128 are arranged such that the toothed portion 126a engages with the toothed portion 128a. The toothed portion 126a and the toothed portion 128a are configured such that when the first gear 126 is rotated with a rotation axis extending in the Z direction, the second gear 128 with a rotation axis extending in the Y direction is rotated by the rotation of the first gear 126. For example, the first gear 126 and the second gear 128 are configured by a bevel gear (e.g., a spiral bevel gear or a straight bevel gear) or a hypoid gear.

[0053] A cover 130 is provided on a side of the second bearing 122, where the nut rotating portion 110b is present. The cover 130 has a rectangular shape in a side view. A part of the cover 130 is thus inserted into the housing 104a (see Fig. 4) that it covers the side surface of the housing 104a opposite the nut rotating portion 110b. The side surface of the cover 130 opposite the second bearing 122 serves as a support surface 130a for supporting the second bearing 122.

[0054] The torque of the rotary shaft 140b is transmitted to the rotary shaft 106 through the gear unit 124 in the following manner. When the rotary shaft 104b of the power transmission unit 104 is rotated by actuating the motor 102 (see Fig. 3), the first gear 126 is rotated, so that the second gear 128 meshing with the first gear 126 is rotated about the axis extending in the Y direction. Accordingly, the rotary shaft 106 integrated with the second gear 128 is rotated about the axis extending in the Y direction, thereby rotating the nut rotating portions 110a and 110b. In this way, the torque of the rotary shaft 104b is transmitted to the rotary shaft 106 through the gear unit 124.

[0055] If the number of teeth of the second gear 128 is greater than the number of teeth of the first gear 126, when the torque of the motor 102 is transmitted to the rotating shaft 106, the rotational speed of the rotating shaft 106 will be lower than the rotational speed of the motor 102 (i.e., the rotational speed of the rotating shaft 102b and the rotating shaft 104b). In other words, the power transmission unit 104 serves as a speed reduction device in this case. In this case, the torque of both the nut rotating section 110a and the nut rotating section 110b can be made greater than the torque of the motor 102.

[0056] As in Fig. As shown in Figure 3, the blade attachment and detachment unit 140 is provided behind the nut attachment and detachment unit 100. The blade attachment and detachment unit 140 includes a motor 142 and a power transmission unit (power transmission mechanism) 144 connected to the motor 142. The motor 142 and the power transmission unit 144 are arranged side by side in the X direction.

[0057] The motor 142 includes a hollow cubic housing 142a and a rotary shaft (not shown) rotatably supported within the housing 142a so as to extend in the Z direction. An upper end portion of this rotary shaft protrudes from the upper surface of the housing 142a, and a disc-shaped roller member (drive pulley) 142b is fixed to this upper end portion of the rotary shaft. Accordingly, when electric power is supplied to the motor 142, the rotary shaft of the motor 142 and the roller member 142b are rotated together about a vertical axis extending in the Z direction. The configuration of the motor 142 can be similar to the configuration of the motor 102 of the nut attachment and detachment unit 100.

[0058] The power transmission unit 144 includes a hollow cubic housing 144a and a rotary shaft 144b rotatably supported within the housing 144a so as to extend in the Z direction. An upper end portion of the rotary shaft 144b protrudes from the upper surface of the housing 144a, and a disc-shaped roller element (drive pulley) 144c is fixed to this upper end portion of the rotary shaft 144b. The housing 144a has a central through-hole 144d extending in the Y direction. A rotary shaft 146 is inserted through the through-hole 144d of the housing 144a, and opposite end portions of the rotary shaft 146 protrude from the right and left side surfaces of the housing 144a. The design of the power transmission unit 144 can be similar to the design of the power transmission unit 104 of the nut attachment and removal unit 100.Furthermore, the design of the rotary shaft 146 can be similar to the design of the rotary shaft 106 of the nut attachment and removal unit 100.

[0059] The motor 142 and the power transmission unit 144 are connected to each other by an endless connecting member 148, such as a belt and a chain. A connection method for connecting the motor 142 and the power transmission unit 144 is similar to that for connecting the motor 102 and the power transmission unit 104 in the nut attachment and detachment unit 100.

[0060] A blade holding unit 150a is attached to one end (left end) of the rotary shaft 146. The blade holding unit 150a serves to fix the (new) cutting blade 80 to the cutting unit 38a (see Fig. 1) and also remove the (old) cutting blade 80 from the cutting unit 38a. Similarly, a blade holding unit 150b is attached to the other end (right end) of the rotary shaft 146. The blade holding unit 150b serves to attach the (new) cutting blade 80 to the cutting unit 38b (see Fig. 1) and also to remove the (old) cutting blade 80 from the cutting unit 38b. The blade holding unit 150a includes a plate-shaped support member 152 having an oval shape in a side view and a pair of blade gripping units 154a and 154b attached to a side surface of the support member 152 on the side opposite the power transmission unit 144. The blade gripping unit 154a is attached to one end portion of the support member 152, and the blade gripping unit 154b is attached to the other end portion of the support member 152. The other blade holding unit 150b has the same configuration as that of the blade holding unit 150a.

[0061] The blade gripping units 154a and 154b each have a cylindrical base 156 attached to the support member 152. The cylindrical base 156 has a front surface 156a oriented toward the side opposite the power transmission unit 144. A positioning pin 158 protrudes from the front surface 156a of the base 156 at the center thereof. The positioning pin 158 has a front end portion configured to be inserted into the recess 78b formed on the support shaft 78 of the attachment 74 (see Fig. 2). That is, the front end portion of the positioning pin 158 is formed to correspond to the position and size of the recess 78b.

[0062] A plurality of gripping elements 160 for gripping the projection 82b (see Fig. 2) the cutting blade 80 are provided on the outer periphery of the base 156 so as to be arranged at substantially equal intervals along the outer periphery of the base 156. Each gripping element 160 is a rod-shaped element extending along the base 156, and a base end portion (one end) of each gripping element 160 is fixed to the outer peripheral surface of the base 156. In the Fig. 3, the four gripping elements 160 are fixed to the base 156. A front end portion (the other end) of each gripping element 160 protrudes from the front surface 156a of the base 156, and a claw portion 160a is formed on this front end portion of each gripping element 160 so as to be inclined toward the center line (axis) of the base 156. A moving mechanism (not shown) for moving the front end portion of each gripping element 160 in the radial direction of the base 156 is stored in the base 156. This moving mechanism serves to selectably assume an operating state in which the claw portion 160a of each gripping element 160 engages with the outer peripheral surface of the projection 82b (see Fig. 2) the cutting blade 80 comes into contact, thereby gripping the cutting blade 80 (closed state), and assumes a non-operating state in which the claw portion 160a is moved radially outward of the base 156 from the above closed state, thereby releasing the gripped state of the cutting blade 80 (open state). The other blade gripping unit 154b has the same configuration as that of the blade gripping unit 154a.

[0063] The blade holding unit 150a serves to hold the (old) cutting blade 80 attached to the cutting unit 38a and also the one attached to the blade holder 52a (see Fig. 1) stored (new) cutting blade 80. Similarly, the blade holding unit 150b serves to hold the (old) cutting blade 80 attached to the cutting unit 38b and also to hold the (old) cutting blade 80 attached to the blade holder 52b (see Fig. 1) to hold the stored (new) cutting blade 80. That is, when changing the cutting blade 80 attached to the cutting unit 38a, the blade holding unit 150a is operated to replace the (old) cutting blade 80 attached to the cutting unit 38a with the (new) cutting blade 80 stored in the blade holder 52a. Similarly, when changing the cutting blade 80 attached to the cutting unit 38b, the blade holding unit 150b is operated to replace the (old) cutting blade 80 attached to the cutting unit 38b with the (new) cutting blade 80 stored in the blade holder 52b. A specific operation of the blade holding units 150a and 150b when changing the cutting blade 80 will be described in detail below.

[0064] As in Fig. As shown in Figure 1, the cutting device 2 further includes a control section (control unit) 90 for controlling each component constituting the cutting device 2. The plurality of components constituting the cutting device 2 (e.g., the moving mechanism 10, the chuck table 14, the moving mechanism 24, the holding unit 26, the moving mechanism 30, the holding unit 32, the moving mechanisms 36a and 36b, the cutting units 38a and 38b, the imaging units 40, the cleaning unit 42, and the blade changing device 50) are connected to the control section 90, and the operation of each component is controlled by the control section 90. For example, the control section 90 is configured by a computer including a processing unit such as a central processing unit (CPU) and a storage unit such as a flash memory.The processing unit is operated according to software stored in the storage unit, thereby realizing the control of each component by the control section 90.

[0065] By using the blade changing device 50 provided in the cutting device 2, the cutting blades 80 attached to the cutting units 38a and 38b can be changed automatically. The operation of the blade changing device 50 when changing the cutting blades 80 attached to the cutting units 38a and 38b will now be described. For ease of illustration, the process when changing the cutting blade 80 attached to the cutting unit 38a will be described.

[0066] First, the moving mechanism 60 is actuated to move the attachment and detachment unit 68 in the X direction so that the blade gripping unit 154b of the blade holding unit 150a (see Fig. 3) a target one of the plurality of (new) cutting blades 80 stored on the blade holder 52a. At this time, by rotating the support shaft 54a of the blade holder 52a to thereby rotate the disc-shaped member 56a, the target cutting blade 80 to be disposed opposite the blade gripping unit 154b can be changed. Thereafter, the moving mechanism (not shown) connected to the blade holder 52a is actuated to move the blade holder 52a in the Y direction so that the target cutting blade 80 disposed opposite the blade gripping unit 154d approaches the blade gripping unit 154b. At this time, the plurality of gripping elements 160 of the blade gripping unit 154b are held in the open state. Thereafter, the projection 82b of the target cutting blade 80 held on the blade holder 52a is positioned within the plurality of gripping elements 160.Thereafter, the plurality of gripping elements 160 are moved radially inward to enter the closed state. Accordingly, the target cutting blade 80 held on the blade holder 52a is gripped by the blade gripping unit 154b. Thereafter, the blade holder 52a is moved away from the blade gripping unit 154b in the Y direction.

[0067] Thereafter, the movement mechanism 60 is actuated to move the attachment and detachment unit 68 in the X direction so that the attachment and detachment unit 68 extends below the second support structure 34 and the first support structure 20, and then positioned so that it is arranged opposite the cutting unit 38a. In Fig. In Figure 1, the attachment and detachment unit 68 is shown above and behind the first support structure 20 and the second support structure 34 for ease of illustration. In fact, however, the attachment and detachment unit 68 is fixed at the same height as the cutting units 38a and 38b and is allowed to pass through the space defined beneath the first support structure 20 and the second support structure 34.

[0068] The attachment and detachment unit 68 is positioned so that the nut rotating section 110a (see Fig. 3) is arranged opposite the (old) cutting blade 80 attached to the cutting unit 38a. The positional relationship between the nut rotating portion 110a and the cutting unit 38a can be adjusted by the moving mechanism 36a and the moving mechanism 60. Thereafter, the moving mechanism 36a is actuated to move the cutting unit 38 toward the nut rotating portion 110a. Accordingly, the nut 86 (see Fig. 2) is moved to the front surface 112a of the rotary member 112 (see Fig. 3) of the nut rotating section 110a. At this time, the plurality of retaining pins 114 of the nut rotating section 110a are inserted into the through holes 86b (see Fig. 2) of the nut 86. When the rotary element 112 is axially pressed by the nut 86, the rotary element 112 is inserted into the cover 118, so that the plurality of gripping elements 116 (see Fig. 3) of the rotary member 112 enters the closed state. Consequently, the nut 86 is gripped by the claw portions 116a of the plurality of gripping elements 116.

[0069] Then the motor 102 (see Fig. 3) to rotate the rotary shaft 106 and thereby rotate the nut rotating portion 110a in a first direction (e.g., the direction shown in Fig. 3 by an arrow A). Consequently, the nut 86 gripped by the nut rotating portion 110a is rotated to be loosened. Then, the nut 86 is removed from the support shaft 78 of the attachment 74 (see Fig. 2). Thereafter, the cutting unit 38a is moved away from the nut rotating section 110a in the Y direction. At this time, the rotating member 112 remains inserted into the cover 118, so that the nut 86 remains held by the nut rotating section 110a even after the nut 86 is removed from the rotating shaft 78.

[0070] Thereafter, the moving mechanism 60 is actuated to move the attaching and detaching unit 68 in the X direction so that the blade gripping unit 154a of the blade holding unit 150a (see Fig. 3) is placed opposite the (old) cutting blade 80 attached to the cutting unit 38a. Thereafter, the moving mechanism 36a is actuated to move the cutting unit 38a toward the blade gripping unit 154a, so that the cutting blade 80 attached to the cutting unit 38a approaches the blade gripping unit 154a. At this time, the plurality of gripping elements 160 of the blade gripping unit 154a are held in the open state. Furthermore, the positioning pin 158 of the blade gripping unit 154a is inserted into the recess 78b of the support shaft 78 of the attachment 74 (see Fig. 2). Accordingly, the blade gripping unit 154a is axially aligned with the cutting blade 80 mounted on the support shaft 78 of the attachment 74. In this state, the projection 82b (see Fig. 2) the cutting blade 80 is positioned radially inside the plurality of gripping elements 160. Thereafter, the plurality of gripping elements 160 are moved radially inward to enter the closed state. Consequently, the projection 82b of the cutting blade 80 attached to the cutting unit 38a is gripped by the claw portions 160a of the plurality of gripping elements 160. Thereafter, the cutting unit 38a is moved away from the blade gripping unit 154a in the Y direction. Accordingly, the (old) cutting blade 80 is removed from the cutting unit 38a and held by the blade gripping unit 154a.

[0071] Then the engine 142 (see Fig. 3) is actuated to rotate the rotary shaft 146 180 degrees. Accordingly, the support member 152 is rotated 180 degrees, thereby changing the position of the blade gripping unit 154a to the position of the blade gripping unit 154b and vice versa. This means that the blade gripping unit 154b holding the (new) target cutting blade 80 is now positioned so that it is opposite the cutting unit 38a.

[0072] Thereafter, the moving mechanism 36a is actuated to move the cutting unit 38a in the Y direction toward the blade gripping unit 154b, so that the cutting unit 38a approaches the blade gripping unit 154b. Accordingly, the support shaft 78 of the attachment 74 is inserted through the opening 82a (see Fig. 2) the target cutting blade 80 held by the blade gripping unit 154b is inserted. Thereafter, the plurality of gripping elements 160 of the blade gripping unit 154b are moved radially outward to assume the open state. Accordingly, the target cutting blade 80 is attached to the support shaft 78 of the attachment 74 fixed to the front end portion of the spindle 72. Thereafter, the cutting unit 38a is moved away from the blade gripping unit 154b in the Y direction.

[0073] Thereafter, the moving mechanism 60 is actuated to move the attaching and detaching unit 68 in the X direction so that the nut 86 (see Fig. 2) holding nut rotating section 110a (see Fig. 3) is positioned opposite the target cutting blade 80 mounted on the cutting unit 38a. Thereafter, the moving mechanism 36a is actuated to move the cutting unit 38a in the Y direction toward the nut rotating portion 110a. Accordingly, the nut 86 held by the nut rotating portion 110a is positioned at the front end of the support shaft 78 of the attachment 74 (see Fig. 2). Then the motor 102 (see Fig. 3) to rotate the rotary shaft 106 and thereby rotate the nut rotating portion 110a in a second direction (e.g., the direction shown in Fig. 3 by an arrow B) opposite to the first direction. Accordingly, the nut 86 is rotated in the second direction to be screwed onto the threaded portion 78a of the support shaft 78 of the attachment 74 (see Fig. 2). Consequently, the target cutting blade 80 is held between the projection 76b of the attachment 74 and the nut 86 and is thus secured to the spindle 72 of the cutting unit 78a.

[0074] As described above, the gear unit 124 (see Fig. 4 and Fig. 5) the first gear 126 and the second gear 128. In this case, since the number of teeth of the second gear 128 is greater than the number of teeth of the first gear 126, a speed reduction device is obtained by the gear unit 124. In the case of using the power transmission unit 104 with the gear unit 124 as a speed reduction device, the torque of the nut rotating section 110a can be increased. Accordingly, when rotating the nut rotating section 110a to loosen the nut 86 (see Fig. 2) screw into the threaded portion 78a of the attachment 74, the nut 86 can be screwed in more securely.

[0075] Thereafter, the cutting unit 38a is moved in the Y direction away from the nut rotating portion 110a. At this time, the rotating member 112 is moved axially outward of the cover 118, so that the plurality of gripping members 116 enter the open state. Accordingly, the gripped state of the nut 86 by the plurality of gripping members 116 is terminated. Thereafter, the moving mechanism 60 is actuated to move the attachment and detachment unit 68 to the initial position (between the blade holders 52a and 52b). In this initial position, the (old) cutting blade 80 held by the blade gripping unit 154a is placed on the blade holder 52a. In this way, the cutting blade 80 is automatically exchanged by the blade exchange device 50. That is, the old cutting blade 80 is automatically replaced with the new cutting blade 80 by the blade exchange device 50.

[0076] While the operation for changing the cutting blade 80 mounted on the cutting unit 38a has been described, the operation for changing the cutting blade 80 mounted on the cutting unit 38b is also performed similarly. In this case, the blade holding unit 150b is operated to replace the (old) cutting blade 80 mounted on the cutting unit 38b with the (new) target cutting blade 80 stored on the blade holder 52b. Furthermore, the nut rotating section 110b is operated to attach and detach the nut 86 for fixing the cutting blade 80 to the cutting unit 38b. The operations of the cutting unit 38b, the nut rotating section 110b, and the blade holding unit 150b when changing the cutting blade 80 attached to the cutting unit 38b are similar to the operations of the cutting unit 38a, the nut rotating section 110a, and the blade holding unit 150a, respectively.

[0077] As described above, the cutting device 2 according to this preferred embodiment includes the blade changing device 50 for changing the cutting blade 80. The blade changing device 50 includes the motor 102, the rotary shaft 106, the nut rotating portion 110a attached to one end of the rotary shaft 106, the nut rotating portion 110b attached to the other end of the rotary shaft 106, and the power transmission unit 104 for transmitting the power of the motor 102 to the rotary shaft 106. The blade changing device 50 can transmit the power of the motor 102 to the nut rotating portions 110a and 110b through the power transmission unit 104 and the rotary shaft 106. That is, the two nut rotating portions 110a and 110b can be driven by the single motor 102.Accordingly, it is not necessary to provide individual motors for the nut rotating sections 100a and 100b, so that the blade changing device 50 can be reduced in size, weight, or cost.

[0078] The configuration of the blade changing device 50 according to this preferred embodiment can be appropriately modified within the range in which the cutting blade 80 can be changed. For example, the blade changing device may further include a moving mechanism for moving the attachment and detachment unit 68 in the Y direction and a moving mechanism for moving the attachment and detachment unit 68 in the Z direction. In this case, the position of the attachment and detachment unit 68 can be controlled by using these moving mechanisms when changing the cutting blade 80.

[0079] While the blade changing device 50 is arranged behind the second support structure 34 in this preferred embodiment, the arrangement of the blade changing device 50 is not limited. For example, the blade holders 52a and 52b and the attachment and detachment unit 68 could be arranged in front of or to the side of the first support structure 20. Furthermore, the mechanism for controlling the movement of the attachment and detachment unit 68 is not limited. For example, a robot arm could be connected to the attachment and detachment unit 68 to control the movement of the attachment and detachment unit 68.

[0080] Furthermore, the configuration of the blade holders 52a and 52b capable of storing the plurality of cutting blades 80 is not limited. For example, each of the blade holders 52a and 52b capable of storing the plurality of cutting blades 80 could be provided with a moving mechanism for moving a selected one of the plurality of cutting blades 80 to a position where the selected cutting blade 80 can be attached to the attachment and detachment unit 68.

[0081] Furthermore, the rotary shaft 106 (see Fig.3) In this preferred embodiment, a single shaft. As a modification, the rotary shaft 106 could be configured from a first rotary shaft (first shaft) and a second rotary shaft (second shaft); the nut rotary portion 110a is fixed to the front end of the first rotary shaft, and the nut rotary portion 110b is fixed to the front end of the second rotary shaft. In this case, the second gear 128 meshing with the first gear 126 is fixed to both the first rotary shaft and the second rotary shaft. Furthermore, the axis of the first rotary shaft is aligned with the axis of the second rotary shaft.

[0082] Any other structures and methods in this preferred embodiment could be suitably modified without departing from the scope of the subject matter of the present invention.

[0083] The present invention is not limited to the details of the preferred embodiment described above. The scope of the invention is defined by the appended claims, and all changes and modifications that fall within the equivalent scope of the claims are therefore encompassed by the invention.

Claims

[1] Cutting device, comprising: a clamping table for holding a workpiece; a pair of first and second cutting units for cutting the workpiece held on the chuck table, each of the first and second cutting units having a spindle and a cutting blade mounted on the spindle; and a blade changing device for changing the cutting blade attached to the spindle of the first cutting unit and for changing the cutting blade attached to the spindle of the second cutting unit, wherein the blade changing device comprises: a nut attaching and detaching unit for attaching and detaching a nut for fixing the cutting blade to the spindle in both the first and second cutting units, and a blade attachment and detachment unit for attaching the cutting blade to the spindle in both the first and second cutting units and detaching the cutting blade from the spindle in both the first and second cutting units, wherein the nut attachment and removal unit comprises: a rotating shaft, a first nut rotating portion attached to one end of the rotating shaft for holding and rotating the nut for fixing the cutting blade to the spindle of the first cutting unit, a second nut rotating portion attached to the other end of the rotating shaft for holding and rotating the nut for fixing the cutting blade to the spindle of the second cutting unit, an engine, and a power transmission unit connected to the motor and the rotating shaft for transmitting the power of the motor to the rotating shaft to thereby rotate the rotating shaft. [2] Cutting device according to claim 1, wherein the rotational axis of the first nut rotating portion is aligned with the rotational axis of the second nut rotating portion. [3] The cutting device according to claim 1 or 2, wherein the power transmission unit comprises a speed reduction device for making the rotational speed of the rotary shaft smaller than the rotational speed of the motor, and for making the torque of the first nut rotating portion and the second nut rotating portion larger than the torque of the motor. [4] Cutting device according to claim 3, wherein the speed reduction device comprises a bevel gear or a hypoid gear.

Images