Processing equipment

Abstract

To promptly detect whether presence or absence of a work-piece received in a reception region of a cassette regardless of a shape of the work-piece and a surface state of a side surface thereof.SOLUTION: A processing device, which processes a work-piece, comprises: a cassette placement table which has a plurality of reception regions capable of receiving work-pieces respectively, and on which cassettes for receiving the work-pieces are placed; carry-out / in units that carry out / in the work-pieces to / from the cassettes; and sensor units that detect whether presence or absence of the work-pieces received in the respective reception regions of the cassettes placed on the cassette placement table. The sensor unit includes: a light emitting unit having a plurality of light emitting parts that can emit light to the plurality of reception regions of the cassette respectively; and a light receiving unit having a plurality of light receiving parts that can receive the light irregularly reflected on side surfaces of the work-pieces, respectively. Thereby, the processing device determines the presence or absence of the work-pieces received in the reception regions on the basis of whether or not the light receiving parts have received the light irregularly reflected on the side surfaces of the work-pieces.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a processing apparatus that processes a plate-shaped workpiece that is carried in a state where the workpiece is accommodated in a cassette. [Background technology]

[0002] A disk-shaped wafer with multiple devices such as ICs and LSIs formed on its surface is processed from the back side using a grinding or polishing machine to thin it to a specified thickness, and then the areas between the devices are processed using a cutting or laser processing machine, and the wafer is divided into individual device chips. The divided device chips are widely used in electrical equipment such as mobile phones and personal computers.

[0003] In processing devices such as grinding devices, polishing devices, cutting devices, and laser processing devices, multiple plate-shaped workpieces are loaded together in a cassette. The cassette has multiple storage areas, each of which stores a plate-shaped workpiece such as a wafer. These storage areas are stacked vertically, and each plate-shaped workpiece is stored in each storage area with its front and back surfaces aligned horizontally. The processing device also has a loading / unloading unit that unloads the workpieces stored in the storage areas of the cassette from the cassette and returns the processed workpieces to the storage areas.

[0004] However, not all storage areas of a cassette are necessarily filled with workpieces. For example, a workpiece may not be processed to a sufficient quality or may be damaged during one of the various processes performed on the workpiece. Further processing of such a workpiece would not produce a finished product of sufficient quality, so the workpiece is removed from the cassette midway through the process. In this case, some of the storage areas of the cassette will be empty. Also, if the number of workpieces is fewer than the number of storage areas, some of the storage areas will be empty from the start.

[0005] Therefore, the processing device is provided with an optical sensor unit for detecting the presence or absence of workpieces accommodated in each storage area when the cassette is loaded. For example, the sensor unit is attached to the loading / unloading unit, and the loading / unloading unit is brought close to the storage area to be detected, and the sensor unit detects the presence or absence of the workpiece. Alternatively, the processing device is provided with an independent sensor unit that can be raised and lowered, and the sensor unit is raised and lowered in front of the cassette to detect the presence or absence of the workpiece in each storage area (see Patent Documents 1 and 2).

[0006] The sensor unit has a light-emitting element and a light-receiving element. For example, the processing device advances the sensor unit into the cassette so that the outer periphery of the disk-shaped workpiece is positioned between the light-emitting element and the light-receiving element, which are aligned along a substantially horizontal plane. The presence or absence of the workpiece is detected based on whether or not light emitted from the light-emitting element reaches the light-receiving element, i.e., whether or not it is blocked by the workpiece.

[0007] In addition, the processing device irradiates light emitted from the light-emitting unit from outside the cassette into the storage area, and detects the presence or absence of a workpiece based on whether or not this light is reflected by the smooth side of the workpiece and reaches the light-receiving unit. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2015-50410 A [Patent Document 2] Japanese Patent Application Publication No. 2018-26486 Summary of the Invention [Problem to be solved by the invention]

[0009] In processing devices, rectangular workpieces, rather than disc-shaped workpieces, may be loaded and processed. When a rectangular workpiece is stored in the storage area, the light-emitting unit and the light-receiving unit cannot be inserted into the storage area so that the workpiece is sandwiched between them. Also, even when the light-emitting unit of the sensor unit positioned outside the cassette irradiates light onto the side of the workpiece and the reflected light is detected by the light-receiving unit, if the side of the workpiece is not smooth, the light will scatter on the side and will not easily reach the light-receiving unit.

[0010] In the first place, it took time to raise and lower the sensor unit in front of the cassette and sequentially detect the presence or absence of workpieces in each storage area, which meant that the workpieces had to be unloaded after the detection was complete, which could reduce the processing efficiency of the processing device.

[0011] The present invention has been made in consideration of such problems, and its purpose is to provide a processing device that can quickly detect the presence or absence of a workpiece stored in a cassette storage area regardless of the shape of the workpiece or the surface condition of its side, and can quickly start the workpiece removal operation. [Means for solving the problem]

[0012] According to one aspect of the present invention, a processing device for processing a workpiece includes a chuck table for holding the workpiece, a processing unit for processing the workpiece held on the chuck table, a first cassette mounting table having a plurality of storage areas each capable of accommodating the workpiece and on which a cassette for accommodating the workpiece is mounted, a carry-in / out unit for carrying the workpiece in and out of the cassette, and a sensor unit for detecting the presence or absence of the workpiece accommodated in each of the storage areas of the cassette mounted on the first cassette mounting table, and the sensor unit detects the presence or absence of the workpiece accommodated in each of the storage areas of the cassette mounted on the first cassette mounting table. The containment area for each of the targets a light emitting unit having a plurality of light emitting portions that can irradiate light to the respective storage areas of the cassette placed on the first cassette placing table; The containment area for each of the targetsa light receiving unit having a plurality of light receiving portions each capable of receiving the light diffusedly reflected by a side surface of the workpiece accommodated in the light receiving unit; The light emitting unit and the light receiving unit are accommodated in the accommodation area of ​​each target without raising or lowering the light emitting unit and the light receiving unit relative to the cassette. The light diffused by the side surface of the workpiece is Each The cassette placed on the first cassette placement table is determined based on whether the light receiving section receives light or not. Each The grinding device is characterized in that it determines whether or not the workpiece is contained in the containing area.

[0013] Preferably, the cassette loading device further includes a second cassette loading table adjacent to the first cassette loading table, The sensor unit is erected adjacent to the first cassette mounting table and the second cassette mounting table and further includes a main body to which the light-emitting unit and the light-receiving unit are attached, and a rotational drive source that can change the orientation of the light-emitting unit and the light-receiving unit by rotating the main body, and determines whether or not the workpiece is contained in the storage area of ​​the cassette placed on the second cassette mounting table by irradiating light from the light-emitting portion of the light-emitting unit onto the storage area of ​​the cassette placed on the second cassette mounting table and receiving the light diffusedly reflected by the side of the workpiece contained in the storage area of ​​the cassette placed on the second cassette mounting table with the light-receiving portion of the light-receiving unit.

[0014] Preferably, the processing unit is a grinding unit capable of grinding the workpiece held by the chuck table. More preferably, when determining whether or not the workpiece is contained in each of the storage areas of the cassettes placed on the first cassette placing table, the detection status of the light by other light receiving units adjacent above and below each of the light receiving units is utilized. [Effects of the Invention]

[0015] A sensor unit of a processing device according to one aspect of the present invention includes a light-emitting unit having a plurality of light-emitting elements that can irradiate light onto a plurality of storage areas of a cassette, and a light-receiving unit having a plurality of light-receiving elements that can receive the light diffusedly reflected by the side surfaces of the workpieces. The processing device determines whether or not the workpieces are stored in the storage areas of the cassette based on whether or not the light-receiving elements receive the light.

[0016] The processing device can simultaneously detect the presence or absence of workpieces in each storage area of ​​the cassette, without the need to raise or lower the sensor unit. Therefore, the presence or absence of workpieces in each storage area of ​​the cassette can be detected instantly. Furthermore, because the sensor unit detects light diffusely reflected from the side of the workpiece, it can detect the presence or absence of workpieces whose side is not smooth, and can also detect workpieces that are not round.

[0017] Therefore, the present invention provides a processing device that can quickly detect the presence or absence of a workpiece stored in the cassette storage area regardless of the shape of the workpiece or the surface condition of its side, and can quickly start the workpiece removal operation. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 2 is a perspective view schematically showing a processing device. [Figure 2] FIG. 2 is a cross-sectional view schematically showing a workpiece accommodated in a cassette and a sensor unit. [Figure 3] FIG. 2 is a plan view schematically showing a workpiece accommodated in a cassette and a sensor unit. [Figure 4] Figure 4(A) is a perspective view showing a schematic diagram of a sensor unit detecting the presence or absence of a workpiece in the storage area of ​​a first cassette, and Figure 4(B) is a perspective view showing a schematic diagram of a sensor unit detecting the presence or absence of a workpiece in the storage area of ​​a second cassette. [Figure 5] Figure 5(A) is a plan view schematically showing how the sensor unit detects the presence or absence of a workpiece in the storage area of ​​the first cassette, and Figure 5(B) is a plan view schematically showing how the sensor unit detects the presence or absence of a workpiece in the storage area of ​​the second cassette. DETAILED DESCRIPTION OF THE INVENTION

[0019] An embodiment of the present invention will be described with reference to the accompanying drawings. The processing apparatus according to this embodiment is, for example, a grinding apparatus that grinds a workpiece such as a disc-shaped semiconductor wafer or a rectangular resin substrate, or a polishing apparatus that polishes the workpiece. Alternatively, it is a cutting apparatus or laser processing apparatus used to divide the workpiece. FIG. 1 shows a grinding apparatus 2 as an example of the processing apparatus according to this embodiment. Hereinafter, a case where the processing apparatus according to this embodiment is the grinding apparatus 2 will be described as an example, but the processing apparatus according to this embodiment is not limited to the grinding apparatus 2.

[0020] Workpieces stored in cassettes 8a and 8b are carried into the grinding device (processing device) 2, and the workpieces carried out from the cassettes 8a and 8b are ground (processed) and returned to the cassettes 8a and 8b. The workpieces ground by the grinding device 2 are made of, for example, silicon, silicon carbide, or other semiconductor materials, or sapphire, glass, or quartz materials. Alternatively, the workpieces are package substrates in which multiple chips are sealed with mold resin, or resin substrates such as printed circuit boards.

[0021] 2 and 3 show a rectangular resin substrate as an example of the workpiece 1. That is, Fig. 2 includes a cross-sectional view that schematically shows the workpiece 1, which is a resin substrate, and Fig. 3 includes a plan view that schematically shows the workpiece 1, which is a resin substrate. Below, the processing device according to this embodiment will be described using an example in which the workpiece 1 is a rectangular resin substrate, but the workpiece 1 is not limited to a rectangular resin substrate.

[0022] 1 is a perspective view schematically showing a grinding apparatus 2. The grinding apparatus 2 has a base 4 that supports each component. A first cassette mounting table 6a and a second cassette mounting table 6b are provided on an upper surface 4a of the front portion of the base 4. However, the number of cassette mounting tables 6a and 6b provided in the grinding apparatus 2 is not limited to two.

[0023] On the first cassette table 6a, for example, a first cassette accommodating the workpiece 1 before grinding is placed. The cassette 8a is placed on the second cassette table 6b. For example, the second cassette 8b is placed on the second cassette table 6b for storing the workpiece 1 after grinding. However, the use of the cassette tables 6a, 6b and the cassettes 8a, 8b is not limited to this. After the workpiece 1 stored in the first cassette 8a has been ground, it may be returned to the first cassette 8a.

[0024] 2 is a cross-sectional view showing cassettes 8a and 8b placed on cassette mounting tables 6a and 6b. Cassettes 8a and 8b are, for example, rectangular box-shaped with a loading / unloading entrance 50 on the horizontal front side, and store multiple workpieces 1 in the internal space so that they are stacked vertically.

[0025] Each of the cassettes 8a and 8b has a plurality of storage areas 48 capable of storing the workpieces 1. Each storage area 48 is defined, for example, by a groove formed horizontally on both inner walls 52 of the internal space. One end of the groove reaches the loading / unloading entrance 50, and the groove is formed at the same height on both inner walls 52 of the internal space. The internal space of each of the cassettes 8a and 8b is formed to have a width and depth corresponding to the workpieces 1.

[0026] When storing the workpiece 1 in the cassettes 8a, 8b, the orientation of the workpiece 1 is aligned horizontally, and the height of the workpiece 1 is adjusted to the storage area 48 where the workpiece 1 is to be stored. Then, the workpiece 1 is inserted horizontally into the cassettes 8a, 8b from the carry-in / out entrance 50, and the workpiece 1 is pushed in along the grooves. Then, both ends of the workpiece 1 are supported by the grooves, and the workpiece 1 is stored in the storage area 48.

[0027] The storage area 48 may be formed by a structure other than a groove formed in the inner wall 52 of the cassettes 8a, 8b. For example, horizontal rails may be fixed to the inner walls 52 of the cassettes 8a, 8b, and the storage area 48 may be formed by the rails. The following description will be given taking as an example a case where the storage area 48 is formed by a groove.

[0028] Each of the cassettes 8a and 8b has a plurality of storage areas 48 arranged vertically inside, and can store the same number of workpieces 1 as the number of storage areas 48. The workpieces 1 stored in the cassettes 8a and 8b are transported between the processing devices, and are pulled out of the cassettes 8a and 8b at each processing device, processed, and then returned to the cassettes 8a and 8b, and the series of processing steps continues.

[0029] Continuing with the description of the grinding apparatus 2, the grinding apparatus 2 includes a carry-in / out unit 10 installed at a position adjacent to the cassette mounting tables 6a and 6b on the base 4. The carry-in / out unit 10 has the function of carrying out the workpiece 1 from the cassettes 8a and 8b placed on the cassette mounting tables 6a and 6b and transporting it to a predetermined destination, and the function of carrying the processed workpiece 1 into the cassettes 8a and 8b.

[0030] 1, the loading / unloading unit 10 is formed by an articulated robot, for example, and extends and retracts by rotating each arm about the connecting portion that connects the arms, thereby freely moving the support portion at the tip. Either or both of the loading / unloading unit 10 and the cassette mounting tables 6a, 6b can be raised and lowered, and by raising or lowering either or both of them, the support portion of the loading / unloading unit 10 can be positioned at a height corresponding to the predetermined storage area 48 of the cassettes 8a, 8b.

[0031] Two openings 14a, 14b are provided on the upper surface of the rear portion of the base 4 of the grinding device 2. Within the openings 14a, 14b, there are provided X-axis moving tables 16a, 16b, on the upper surfaces of which are placed chuck tables 20a, 20b that suction-hold the workpiece 1. The X-axis moving tables 16a, 16b can be moved in the X-axis direction by an X-axis moving mechanism (not shown).

[0032] Inside the openings 14a, 14b, the outside of the X-axis moving tables 16a, 16b is covered with dustproof and drip-proof covers 18a, 18b that can expand and contract in accordance with the movement of the X-axis moving tables 16a, 16b. The X-axis moving mechanism is protected by the dustproof and drip-proof covers 18a, 18b.

[0033] The X-axis moving tables 16a and 16b are positioned, by the function of the X-axis moving mechanism, into a loading / unloading area where the workpiece 1 is attached and detached on the chuck tables 20a and 20b, and into a processing area where the workpiece 1 held by suction on the chuck tables 20a and 20b is ground.

[0034] Porous members 22a and 22b having the same planar shape as the workpiece 1 are exposed on the upper surfaces of the chuck tables 20a and 20b. The upper surfaces of the porous members 22a and 22b of the chuck tables 20a and 20b serve as holding surfaces for holding the workpiece 1.

[0035] The chuck tables 20a, 20b are provided with suction paths (not shown) inside, one end of which is connected to the porous members 22a, 22b and the other end of which is connected to a suction source (not shown). When the suction source is activated, a negative pressure acts on the workpiece 1 placed on the holding surface, and the workpiece 1 is sucked and held on the chuck tables 20a, 20b. The chuck tables 20a, 20b can also rotate around an axis perpendicular to the holding surface.

[0036] Above the processing areas of the openings 14a, 14b, grinding units (processing units) 32a, 32b are disposed, respectively, for grinding (processing) the workpiece 1 held on the chuck tables 20a, 20b. Two support parts 24a, 24b are erected at the rear end of the base 4 of the grinding device 2, and the grinding units 32a, 32b are supported by the support parts 24a, 24b.

[0037] A pair of Z-axis guide rails 26a, 26b extending in the Z-axis direction are provided on the front surface of each of the support portions 24a, 24b, and Z-axis moving plates 28a, 28b are slidably attached to each of the Z-axis guide rails 26a, 26b.

[0038] A nut portion (not shown) is provided on the back surface (rear surface) of each of Z-axis moving plates 28a, 28b, and Z-axis ball screws 30a, 30b parallel to Z-axis guide rails 26a, 26b are threadedly engaged with the nut portion. Z-axis pulse motors 31a, 31b are connected to one end of each of Z-axis ball screws 30a, 30b.

[0039] When Z-axis ball screws 30a, 30b are rotated by Z-axis pulse motors 31a, 31b, Z-axis moving plates 28a, 28b move in the Z-axis direction along Z-axis guide rails 26a, 26b. Grinding units (processing units) 32a, 32b are fixed to the lower front sides of Z-axis moving plates 28a, 28b, respectively. When Z-axis moving plates 28a, 28b are moved in the Z-axis direction, grinding units 32a, 32b can be moved in the Z-axis direction.

[0040] Each grinding unit 32a, 32b includes a spindle 34a, 34b rotated by a motor connected to the base end, and a grinding wheel 42a, 42b fixed to a mount 36a, 36b disposed on the tip side of the spindle 34a, 34b. Each grinding wheel 42a, 42b includes an annular wheel base 38a, 38b made of a material such as aluminum, and a grinding stone 40a, 40b disposed annularly on the underside of the wheel base 38a, 38b.

[0041] When the motors are operated to rotate the spindles 34a and 34b, the grinding wheels 42a and 42b rotate, and the grinding stones 40a and 40b rotate and move on the circular orbits. In this state, the grinding units 32a and 32b are lowered and the grinding stones 40a and 40b are brought into contact with the workpiece 1 held on the chuck tables 20a and 20b, whereby the workpiece 1 is ground (processed).

[0042] The grinding apparatus 2 is further provided with a spinner cleaning device 44 that cleans and spin-dries the workpiece 1 ground by the grinding units 32a and 32b. The spinner cleaning device 44 includes a spinner table (not shown) that supports the workpiece 1, and a supply nozzle that supplies fluid to the workpiece 1 held on the spinner table. The spinner table that supports the workpiece 1 is rotated at high speed, and cleaning water is supplied to the workpiece 1 from the supply nozzle, thereby cleaning the workpiece 1.

[0043] When grinding the workpiece 1 with the grinding device 2, first, the carry-in / out unit 10 carries the workpiece 1 out of the cassettes 8a, 8b and transfers it to the chuck tables 20a, 20b located in the carry-in / out area. The workpiece 1 is then suction-held by the chuck tables 20a, 20b, and the chuck tables 20a, 20b are sent to the grinding area below the grinding units 32a, 32b. Thereafter, the spindles 34a, 34b are rotated, the grinding units 32a, 32b are lowered to a predetermined height, and the workpiece 1 is ground with the grinding wheels 40a, 40b.

[0044] After grinding the workpiece 1 by the grinding units 32a, 32b to thin it to a predetermined thickness, the chuck tables 20a, 20b are returned to the carry-in / out area, and the suction holding of the workpiece 1 by the chuck tables 20a, 20b is released. Then, the carry-in / out unit 10 transports the workpiece 1 from the chuck tables 20a, 20b to the spinner cleaning device 44, where the workpiece 1 is cleaned. Then, the carry-in / out unit 10 is operated to transport the workpiece 1 from the spinner cleaning device 44 to the cassettes 8a, 8b and store it there.

[0045] In the grinding device 2, the workpieces 1 accommodated in the respective storage areas 48 of the cassettes 8a, 8b are successively drawn out, processed, and returned to the cassettes 8a, 8b. After grinding (processing) of all the workpieces 1 accommodated in the respective storage areas 48 of the cassettes 8a, 8b is completed, the cassettes 8a, 8b are carried out from the cassette mounting tables 6a, 6b.

[0046] Here, not all of the storage areas 48 of the cassettes 8a and 8b are necessarily filled with workpieces. That is, some of the storage areas 48 of the cassettes 8a and 8b may be empty. If the support part of the carry-in / out unit 10 is inserted into an empty storage area 48, no workpiece 1 is present, and not only will the workpiece 1 fail to be drawn out, but the drawing operation will waste time.

[0047] Therefore, the grinding device 2 uses a sensor unit that can inspect the inside of the cassettes 8a, 8b placed on the cassette mounting tables 6a, 6b and detect the presence or absence of the workpiece 1 in each storage area 48. Conventionally, a sensor unit that moves up and down in front of the cassettes 8a, 8b has been used. The sensor unit then irradiates light onto the storage area 48 and detects the light reflected by the side surface 3 of the workpiece 1 to detect the presence or absence of the workpiece 1. This detection operation is performed sequentially for each storage area 48.

[0048] However, the side surface 3 of the workpiece 1 is not always smooth and sufficient light reflection occurs. For example, if the workpiece 1 is a rectangular resin substrate, the side surface 3 will have minute irregularities, and light will be scattered even when irradiated onto the side surface 3. In this case, the light reflected by the side surface 3 of the workpiece 1 may not be detected with sufficient intensity, resulting in insufficient detection accuracy for the presence or absence of the workpiece 1.

[0049] Furthermore, it took time to raise and lower the sensor unit in front of the cassette and sequentially detect the presence or absence of the workpiece 1 in each storage area 48. As a result, the workpiece 1 had to be unloaded until detection of the workpiece 1 was complete, which could be a factor in reducing the efficiency of processing the workpiece 1 in the grinding device 2. Therefore, the grinding device 2 according to this embodiment uses a sensor unit 46 that can instantly detect the presence or absence of the workpiece 1 in each storage area 48 of the cassette without requiring a lifting operation.

[0050] Next, the configuration of the sensor unit 46 and the operation of detecting the workpiece 1 using the sensor unit 46 will be described. The sensor unit 46 detects the presence or absence of the workpiece 1 stored in the storage areas 48 of the cassette 8a placed on the first cassette table 6a and the cassette 8b placed on the second cassette table 6b. As shown in Fig. 1, the sensor unit 46 is provided near the cassette tables 6a and 6b. Fig. 2 includes a side view that schematically shows the sensor unit 46.

[0051] The sensor unit 46 includes, for example, a rod-shaped main body 60 standing adjacent to the first cassette mounting table 6a and the second cassette mounting table 6b. A light-emitting unit 54 including a plurality of light-emitting portions 54a and a light-receiving unit 56 including a plurality of light-receiving portions 56a are attached to the main body 60. The sensor unit 46 also includes a rotational drive source 58 that can rotate the main body 60 to change the orientation of the light-emitting unit 54 and the light-receiving unit 56. The rotational drive source 58 is, for example, a motor.

[0052] The plurality of light-emitting portions 54a of the light-emitting unit 54 can irradiate light onto the plurality of storage areas 48 of the cassette 8a placed on the first cassette mounting table 6a and the cassette 8b placed on the second cassette mounting table 6b, respectively. The light-emitting unit 54 preferably includes the same number of light-emitting portions 54a as the number of storage areas 48 of the cassettes 8a, 8b. The light-emitting portions 54a are preferably attached to the main body 60 at height positions corresponding to the respective storage areas 48 of the cassettes 8a, 8b.

[0053] Furthermore, the multiple light receiving portions 56a of the light receiving unit 56 can receive light diffused by the side surfaces 3 of the workpieces 1 stored in the multiple storage areas 48 of the cassette 8a placed on the first cassette placing table 6a and the cassette 8b placed on the second cassette placing table 6b. The light receiving unit 56 preferably includes the same number of light receiving portions 56a as the number of storage areas 48 of the cassettes 8a, 8b. The light receiving portions 56a are preferably attached to the main body 60 at height positions corresponding to the respective storage areas 48 of the cassettes 8a, 8b.

[0054] The light-emitting unit 54a is a light source such as an LED or a lamp. The light emitted by the light-emitting unit 54a may be white light or monochromatic light. The light-receiving unit 56a is a light-receiving element such as a CMOS sensor or a CCD sensor. The light-receiving unit 56a can receive light of at least the wavelength of the light emitted by the light-emitting unit 54a.

[0055] A control unit including a computer or the like that controls each component of the grinding device (processing device) 2 is connected to the rotation drive source 58, the light emitting unit 54, and the light receiving unit 56. The control unit has a function of controlling the sensor unit 46 to detect the presence or absence of the workpiece 1 in each storage area 48 of the cassettes 8a, 8b.

[0056] When the cassettes 8a, 8b are placed on the cassette mounting tables 6a, 6b, the grinding device 2 activates the sensor unit 46. As shown in Figures 2 and 3, the sensor unit 46 activates each light-emitting portion 54a of the light-emitting unit 54 to irradiate each storage area 48 of the cassettes 8a, 8b with light 62. In Figures 2 and 3, the light 62 emitted from the light-emitting portion 54a is indicated by a dashed line.

[0057] When the workpiece 1 is stored in the storage area 48 irradiated with the light 62, the light 62 strikes the side surface 3 of the workpiece 1. The light 62 is diffusely reflected by the side surface 3 of the workpiece 1 depending on the state of the side surface 3, and part of the light 62 heads toward the light receiving section 56a of the light receiving unit 56. In Figures 2 and 3, light 64 that is diffusely reflected by the side surface 3 of the workpiece 1 and heads toward the light receiving section 56a is shown by a dashed line. When the light 64 is received, the light receiving section 56a sends an electrical signal indicating that the light 64 has been received to the control unit of the grinding device 2.

[0058] Furthermore, if the workpiece 1 is not accommodated in the accommodation area 48 onto which the light 62 is irradiated, the light 62 strikes the workpiece 1 and does not cause diffuse reflection. That is, the light receiving portion 56a of the light receiving unit 56 does not receive the light 64 that is diffusely reflected by the side surface 3 of the workpiece 1. When the control unit of the grinding device 2 causes the light emitting portion 54a to emit light 62 but does not receive an electrical signal from the light receiving portion 56a indicating that the light 64 has been received, the control unit of the grinding device 2 determines that the light receiving portion 56a has not received the light 64.

[0059] Then, the control unit of the grinding device 2 determines whether or not the workpiece 1 is contained in the storage area 48 of the cassettes 8a, 8b placed on the cassette mounting tables 6a, 6b based on whether or not the light receiving portion 56a of the light receiving unit 56 receives the light 64 diffusely reflected by the side surface 3 of the workpiece 1.

[0060] That is, when the light receiving unit 56a receives the light 64, it is determined that the workpiece 1 is stored in the target storage area 48 of the cassettes 8a, 8b. On the other hand, when the light receiving unit 56a does not receive the light 64, it is determined that the workpiece 1 is not stored in the target storage area 48 of the cassettes 8a, 8b. In this way, the grinding device (processing device) 2 detects the workpiece 1 stored in the storage area 48 based on the light 64 diffusedly reflected by the side surface 3 of the workpiece 1, and therefore can detect the workpiece 1 regardless of the state of the side surface 3.

[0061] The sensor unit 46 is provided with a dedicated light-emitting unit 54a and a light-receiving unit 56a for each of the plurality of storage areas 48 of the cassettes 8a, 8b, and can simultaneously detect the presence or absence of the workpiece 1 stored in each of the storage areas 48. Therefore, the grinding device 2 can instantly determine the presence or absence of the workpiece 1 stored in each storage area 48 without raising and lowering the light-emitting unit 54a and the light-receiving unit 56a in front of the cassettes 8a, 8b.

[0062] For example, when using the reflection of light generated by the side surface 3 of the workpiece 1, the arrangement of the light emitting unit and the light receiving unit of the sensor unit must be determined so that the angle of incidence at which the light emitted by the light emitting unit is incident on the side surface 3 matches the angle of reflection of the light reflected by the side surface 3. In this case, when performing the detection operation, the sensor unit must be moved to the front of the target cassettes 8a, 8b, and after the detection operation is completed, the sensor unit must be moved further so as not to interfere with the loading and unloading operation of the workpiece 1.

[0063] In contrast, the grinding device (processing device) 2 according to this embodiment detects the presence or absence of the workpiece 1 in the storage area 48 using diffused reflection of light occurring on the side surface 3 of the workpiece 1. Therefore, unlike when using the reflection of light occurring on the side surface 3 of the workpiece 1, there are fewer restrictions on the path of light between the light 62 that the light emitter 54a irradiates the workpiece 1 and the light 64 that the light receiver 56a receives. For example, the sensor unit 46 can be placed in a position that does not interfere with the operation of carrying in and out the workpiece 1, and in this case, there is no need to move the sensor unit 46 before and after the detection operation.

[0064] However, if the distance between the multiple storage areas 48 in the cassettes 8a and 8b is too close, the light 64 diffusely reflected by the side surface 3 of the workpiece 1 stored in the storage area 48 to be detected is likely to reach the light receiving units 56a adjacent above and below the light receiving unit 56a responsible for that storage area 48.

[0065] Therefore, in order to prevent detection errors, it is preferable that the storage areas 48 of the cassettes 8a and 8b are spaced apart from one another by a predetermined distance or more. For example, it is preferable that the storage areas 48 are spaced apart from one another by a distance of 10 mm or more, and more preferably by a distance of 20 mm or more.

[0066] When the grinding device 2 includes a plurality of cassette mounting tables 6a, 6b, the grinding device 2 may include a plurality of sensor units 46 that detect the workpieces 1 accommodated in the cassettes 8a, 8b mounted on each of the cassette mounting tables 6a, 6b. Alternatively, the grinding device 2 may include a single sensor unit 46 that can detect the workpieces 1 accommodated in the cassettes 8a, 8b mounted on each of the cassette mounting tables 6a, 6b. In other words, the sensor unit 46 may be capable of switching between the cassettes 8a, 8b that are the detection target.

[0067] Fig. 4(A) is a perspective view that schematically shows how the sensor unit 46 detects the presence or absence of the workpiece 1 stored in each storage area 48 of the first cassette 8a placed on the first cassette mounting table 6a. Fig. 5(A) is a plan view that schematically shows how the sensor unit 46 detects the presence or absence of the workpiece 1 stored in each storage area 48 of the first cassette 8a.

[0068] 4(B) is a perspective view that schematically shows how the sensor unit 46 detects the presence or absence of the workpiece 1 stored in each storage area 48 of the second cassette 8b placed on the second cassette mounting table 6b. Also, FIG. 5(B) is a plan view that schematically shows how the sensor unit 46 detects the presence or absence of the workpiece 1 stored in each storage area 48 of the second cassette 8b.

[0069] The orientation of the main body 60 of the sensor unit 46 can be changed by operating the rotation drive source 58 shown in Fig. 2. The sensor unit 46 can switch between the cassettes 8a and 8b that are to be detected for the presence or absence of the workpieces 1 accommodated in each accommodation area 48 by rotating the main body 60 to change the orientation of the light-emitting unit 54 and the light-receiving unit 56.

[0070] For example, a first cassette 8a containing workpieces 1 before being machined is placed on the first cassette mounting table 6a. When the first cassette 8a is placed on the first cassette mounting table 6a, the sensor unit 46 activates the light emitting unit 54 and the light receiving unit 56 to detect the presence or absence of the workpieces 1 contained in each of the storage areas 48. Then, the grinding device 2 activates the carry-in / out unit 10 to carry out the workpieces 1 from the first cassette 8a, and proceeds with grinding each workpiece 1 in turn.

[0071] Furthermore, for example, a second cassette 8b for storing the processed workpieces 1 is placed on the second cassette placing table 6b. When the second cassette 8b is placed on the second cassette placing table 6b, the sensor unit 46 activates the light emitting unit 54 and the light receiving unit 56 to confirm that each storage area 48 is empty. Then, the grinding device 2 activates the carry-in / out unit 10 to sequentially store the workpieces 1 for which grinding (processing) has been completed into the second cassette 8b.

[0072] However, the sensor unit 46 may use other methods to switch between the cassettes 8a and 8b that are the targets for detecting the presence or absence of the workpiece 1. For example, the grinding device 2 may be provided with a movement mechanism that can move the sensor unit 46 in a substantially horizontal direction on the upper surface 4a of the base 4, and the sensor unit 46 may move on the upper surface 4a of the base 4. In this case, even if the number of cassette mounting tables provided in the grinding device 2 exceeds two, one sensor unit 46 can detect the presence or absence of the workpiece 1 in the cassettes mounted on each cassette mounting table.

[0073] The rotary drive source 58 that rotates the main body 60 of the sensor unit 46 may be used for other purposes. For example, by operating the rotary drive source 58 to change the orientation of the sensor unit 46, the irradiation position of the light 62 emitted from the light-emitting portion 54a of the light-emitting unit 54 on the side surface 3 of the workpiece 1 can be changed.

[0074] For example, inside the cassettes 8a and 8b, the workpiece 1 may be improperly accommodated, with one end accommodated in the groove defining the accommodation area 48 and the other end accommodated in another groove adjacent to the first groove but not at the same height. In this case, the workpiece 1 tilts in the internal space of the cassettes 8a and 8b.

[0075] In this case, when the light 62 is irradiated onto the side surface 3 of the workpiece 1 while changing the orientation of the main body 60 of the sensor unit 46 to change the irradiation position, the detection state of the light 64 diffusely reflected by the side surface 3 by the light receiving unit 56a changes. Then, the grinding device 2 can detect an abnormality in the storage state of the workpiece 1 in the cassettes 8a, 8b by referring to the change in the detection state of the light 64 when the orientation of the main body 60 of the sensor unit 46 is changed.

[0076] The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the above-described embodiment, the sensor unit 46 detects the presence or absence of the workpiece 1 in the storage area 48 based on whether the light 62 is emitted from the light-emitting element 54a and the light 64 diffusely reflected by the side surface 3 of the workpiece 1 is detected by the light-receiving element 56a corresponding to the light-emitting element 54a. However, the grinding device 2 according to this embodiment is not limited to this.

[0077] For example, the sensor unit 46 does not need to detect the light 64 diffusely reflected by the side surface 3 of the workpiece 1 only with the light-receiving unit 56a corresponding to the light-emitting unit 54a that emitted the light 62. For example, the grinding device 2 may also detect the light 64 with other light-receiving units 56a adjacent to the light-receiving unit 56a above and below, and may determine the presence or absence of the workpiece 1 using the detection status of the light 64 by the other light-receiving units 56a adjacent above and below as supporting evidence.

[0078] The light 64 diffusely reflected by the side surface 3 of the workpiece 1 has a weaker intensity than light reflected by a smooth surface. In the grinding device 2 according to this embodiment, the presence or absence of the workpiece 1 is detected using the light 64, which has a relatively low intensity, and therefore, in order to improve the detection accuracy, the light 64 may be detected using a plurality of light receiving units 56a.

[0079] 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]

[0080] 1 Workpiece 3. Aspects 2 Grinding equipment 4 Foundation 4a Top side 6a, 6b Cassette placement table 8a,8b cassette 10 Loading / unloading unit 14a,14b opening 16a, 16b X-axis moving table 18a, 18b Dustproof and water-resistant cover 20a, 20b Chuck table 22a, 22b Porous member 24a,24b Support part 26a, 26b Z-axis guide rail 28a, 28b Z-axis moving plate 30a, 30b Z-axis ball screw 31a, 31b Z-axis pulse motor 32a, 32b Grinding unit 34a, 34b Spindle 36a,36b Mount 38a, 38b Wheel base 40a, 40b Grinding wheels 42a, 42b Grinding wheels 44 Spinner cleaning device 46 Sensor Unit 48 Containment Area 50 Loading / unloading entrance 52 Inner wall 54 Lighting unit 54a Light-emitting part 56 Light receiving unit 56a Light receiving part 58 Rotational drive source 60 Main Unit 62,64 light

Claims

1. A processing device for processing a workpiece, a chuck table for holding the workpiece; a processing unit that processes the workpiece held on the chuck table; a first cassette mounting table having a plurality of storage areas each capable of accommodating the workpiece, on which a cassette for accommodating the workpiece is placed; a carry-in / out unit for carrying the workpiece in and out of the cassette; a sensor unit that detects the presence or absence of the workpiece accommodated in each of the accommodation areas of the cassette placed on the first cassette placement table, The sensor unit comprises: a light-emitting unit having a plurality of light-emitting portions capable of irradiating light onto respective target storage areas among the plurality of storage areas of the cassette placed on the first cassette placement table; a light receiving unit having a plurality of light receiving portions capable of receiving the light diffusedly reflected by a side surface of the workpiece accommodated in each of the plurality of accommodation areas of the cassette placed on the first cassette placement table, A processing device characterized by determining whether or not a workpiece is contained in each storage area of ​​the cassette placed on the first cassette loading table based on whether or not each light receiving unit receives the light diffusely reflected by the side of the workpiece contained in the storage area of ​​each target, without raising or lowering the light emitting unit and the light receiving unit relative to the cassette.

2. further comprising a second cassette mounting table adjacent to the first cassette mounting table; The sensor unit comprises: a main body provided adjacent to the first cassette mounting table and the second cassette mounting table, the main body having the light emitting unit and the light receiving unit attached thereto; a rotation drive source that can rotate the main body to change the orientation of the light emitting unit and the light receiving unit, The processing device described in claim 1, characterized in that the presence or absence of the workpiece contained in the storage area of ​​the cassette placed on the second cassette placing table is determined by irradiating light from the light-emitting portion of the light-emitting unit onto the storage area of ​​the cassette placed on the second cassette placing table, and receiving the light diffusedly reflected by the side of the workpiece contained in the storage area of ​​the cassette placed on the second cassette placing table with the light-receiving portion of the light-receiving unit.

3. 3. The processing apparatus according to claim 1, wherein the processing unit is a grinding unit capable of grinding the workpiece held by the chuck table.

4. A processing apparatus as described in any one of claims 1 to 3, characterized in that when determining whether or not the workpiece is contained in each of the storage areas of the cassettes placed on the first cassette loading table, the detection status of the light by other light receiving units adjacent to the above and below of each of the light receiving units is utilized.

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