Abrasive jetting device, abrasive jetting method, article manufacturing method, program, and recording medium

Abstract

To provide a blast processing device which can achieve high processing accuracy even when an accumulation amount of a polishing material in a polishing material tank fluctuates.SOLUTION: A polishing material jetting device includes a storage part for storing a polishing material, a polishing material supply part having a sensor for measuring a storage amount of the polishing material stored in the storage part, a jetting nozzle for mixing the polishing material supplied from the polishing material supply part with an air flow, and jetting the mixture toward workpiece, and a control part, in which the control part sets a rotation speed of a screw of supplying the polishing material toward the jetting nozzle from the storage part to be relatively small when a measurement value of the sensor is relatively large, and sets the rotation speed of the screw to be relatively large when the measurement value of the sensor is relatively small.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an abrasive jetting device, an abrasive jetting method, etc. More specifically, the present invention relates to a method for supplying an abrasive to a jetting head and a method for controlling the position of the jetting head in a suction-type abrasive jetting device that mixes a driving flow such as compressed air and an abrasive in a mixing tube and jets the mixture onto a workpiece. [Background technology]

[0002] Conventionally, blast processing devices that process workpieces by spraying abrasives together with compressed air have been known. Blasting processing devices are used for a variety of purposes, including surface cleaning processes such as removing rust and coatings, shaping processes such as deburring, roughening processes such as matte finish processing, and polishing processes to flatten the surfaces of wafers and substrates.

[0003] In blast processing, for example, the moving speed of the jet nozzle or the distance between the jet nozzle and the workpiece (workpiece) is controlled to adjust the amount of processing (amount of grinding). The former is called residence time control, and is a method in which the moving speed of the jet nozzle is slowed down to increase the residence time at positions on the workpiece where the amount of grinding is desired to be increased, and the moving speed of the jet nozzle is increased to decrease the residence time at positions on the workpiece where the amount of grinding is desired to be decreased. The latter is a method in which the distance between the jet nozzle and the workpiece is decreased at positions on the workpiece where the amount of grinding is desired to be increased, and the distance between the jet nozzle and the workpiece is increased at positions on the workpiece where the amount of grinding is desired to be decreased.

[0004] In recent years, there has been a demand for improved processing accuracy in blast processing, and a demand for stabilizing the amount of grinding (processing rate) of the workpiece ground per unit time. Whether controlling the residence time of the jet nozzle or the distance between the jet nozzle and the workpiece, if the processing rate fluctuates over time, the amount of grinding will be excessive or insufficient, resulting in a decrease in processing accuracy.

[0005] Patent Document 1 discloses an abrasive supplying device in which metering holes are provided at equal intervals on a rotating disk that rotates horizontally inside an abrasive tank in order to stabilize the amount of abrasive supplied from the abrasive tank to an abrasive transport path. The abrasive supplying device described in Patent Document 1 is a device for stably supplying abrasive to a suction-type abrasive jet nozzle.

[0006] Here, the suction type abrasive jet nozzle refers to an abrasive jet nozzle that sucks an abrasive into an abrasive introduction chamber under negative pressure, mixes the abrasive with a driving flow such as compressed air in a mixing tube, and jets it toward a workpiece. Hereinafter, when the term abrasive jet nozzle is used, it refers to a suction type abrasive jet nozzle unless otherwise specified.

[0007] Patent Document 2 also discloses a method of controlling the rotation speed of a screw according to the load applied to the drive source of a screw conveyor that supplies abrasive from an abrasive tank to an abrasive injection nozzle. The bulk specific gravity of the abrasive filled at the bottom of the supply tank increases or decreases due to an increase or decrease in the amount of abrasive in the supply tank in which the screw conveyor is arranged and a change in the pressure in the supply tank. This is detected by the change in the load applied to the drive source of the screw conveyor, and the screw rotation speed is controlled to adjust the amount of abrasive supplied.

[0008] Patent document 3 also discloses that the amount of powder (abrasive) accumulated in a hopper (abrasive tank) is measured using a sensor, and the pressure of the air blown into the hopper is controlled in proportion to the measured amount of accumulation. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2008-264912 A [Patent Document 2] Japanese Patent Application Publication No. 11-333726 [Patent Document 3] JP 2002-346929 A Summary of the Invention [Problem to be solved by the invention]

[0010] Conventional blast processing devices have not yet been able to sufficiently improve the processing accuracy of blast processing. For example, in the abrasive supplying device disclosed in Patent Document 1, which has measuring holes spaced at equal intervals, the measuring accuracy of the volume of the abrasive supplied is increased, but when the bulk density of the abrasive changes, the actual mass of the abrasive supplied fluctuates, causing fluctuations in the processing rate.

[0011] In this regard, although Patent Document 2 focuses on the change in bulk density of the abrasive, the change in the load applied to the drive source of the screw conveyor when the bulk density changes is small, so the measurement accuracy is insufficient and it is not possible to sufficiently suppress fluctuations in the processing rate.

[0012] In addition, in Patent Document 3, the amount of abrasive accumulated in the abrasive tank is measured using a sensor, and the air pressure is controlled in proportion to the amount of accumulated abrasive. However, proportional control of the air pressure is not sufficient to suppress fluctuations in the processing rate. Therefore, there has been a demand for a blast processing device that can achieve high processing accuracy even if the amount of abrasive accumulated in the abrasive tank fluctuates. [Means for solving the problem]

[0013] The first aspect of the present invention is a polishing apparatus comprising: a storage section for storing an abrasive; top surface the control unit relatively reduces the rotational speed of a screw that supplies abrasive from the storage unit to the injection nozzle when the measurement value of the sensor is relatively large, and relatively increases the rotational speed of the screw when the measurement value of the sensor is relatively small.

[0014] A second aspect of the present invention is a polishing apparatus comprising: a storage section for storing an abrasive; top surface the control unit controls the moving mechanism to make the distance between the injection nozzle and the workpiece relatively large when the measurement value of the sensor is relatively large, and to make the distance between the injection nozzle and the workpiece relatively small when the measurement value of the sensor is relatively small.

[0015] A third aspect of the present invention is a polishing apparatus comprising: a storage section for storing an abrasive; top surface the control unit controls the moving mechanism to relatively increase the scanning speed of the injection nozzle relative to the workpiece when the measurement value of the sensor is relatively large, and relatively decrease the scanning speed of the injection nozzle relative to the workpiece when the measurement value of the sensor is relatively small.

[0016] A fourth aspect of the present invention is a polishing apparatus comprising: a storage section for storing an abrasive; top surface the abrasive injection device comprising: an abrasive supply unit equipped with a sensor for measuring the height of the abrasive; an injection nozzle for mixing the abrasive supplied from the abrasive supply unit with an air flow and injecting it toward a workpiece; and a control unit, wherein the control unit makes the pressure and / or flow rate of the air flow relatively small when the measurement value of the sensor is relatively large, and makes the pressure and / or flow rate of the air flow relatively large when the measurement value of the sensor is relatively small.

[0017] In addition, the fifth aspect of the present invention is a method for cleaning an abrasive stored in a storage section. top surface the height of the abrasive is measured by a sensor, and when the measurement value of the sensor is relatively large, the rotational speed of the screw that supplies the abrasive from the storage section to the injection nozzle is made relatively small, and when the measurement value of the sensor is relatively small, the rotational speed of the screw is made relatively large, and the abrasive is injected from the injection nozzle towards the workpiece.

[0018] In addition, a sixth aspect of the present invention is a method for cleaning an abrasive stored in a storage section. top surface a sensor measures the height of the workpiece, and when the sensor measurement value is relatively large, the distance between the injection nozzle and the workpiece is made relatively large, and when the sensor measurement value is relatively small, the distance between the injection nozzle and the workpiece is made relatively small.

[0019] In addition, the seventh aspect of the present invention is a method for cleaning an abrasive stored in a storage section. top surface a height of the workpiece is measured by a sensor, and when the measurement value of the sensor is relatively large, the scanning speed of the injection nozzle relative to the workpiece is made relatively large, and when the measurement value of the sensor is relatively small, the scanning speed of the injection nozzle relative to the workpiece is made relatively small.

[0020] In addition, an eighth aspect of the present invention is a method for cleaning an abrasive stored in a storage section. top surface a sensor measures the height of the abrasive, and when the sensor measurement value is relatively large, the pressure and / or flow rate of the air flow which is mixed with the abrasive and sprayed toward the workpiece is made relatively small, and when the sensor measurement value is relatively small, the pressure and / or flow rate of the air flow is made relatively large. Effect of the Invention

[0021] According to the present invention, it is possible to provide a blast processing device that can achieve high processing accuracy even if the amount of abrasive accumulated in the abrasive tank varies. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic diagram for explaining the configuration of a blast processing device according to a first embodiment. [Diagram 2] FIG. 11 is a schematic diagram for explaining the configuration of a blast processing device according to a second embodiment. [Diagram 3] FIG. 11 is a schematic diagram for explaining the configuration of a blast processing device according to a third embodiment. [Figure 4] FIG. 11 is a schematic diagram for explaining the configuration of a blast processing device according to a fourth embodiment. [Diagram 5] FIG. 1A is a diagram for explaining control parameters according to the first embodiment; FIG. 1B is a diagram for explaining control parameters according to the second embodiment; [Figure 6] FIG. 13A is a diagram for explaining control parameters according to the third embodiment; FIG. 13B is a diagram for explaining control parameters according to the fourth embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A blast processing device according to an embodiment of the present invention will be described with reference to the drawings. In the drawings referred to in the following description of the embodiments and examples, elements denoted by the same reference numbers have the same functions unless otherwise specified.

[0024] [Embodiment 1] The schematic configuration of a blast processing device according to the first embodiment will be described with reference to FIG. The blast processing device 50 includes an abrasive jet nozzle 10 that jets an abrasive to process a workpiece 100, an abrasive supply device 20 that supplies an abrasive to the abrasive jet nozzle 10, and a control unit 25. The abrasive jet nozzle 10 is movably supported by a moving means (not shown) that enables relative movement with respect to the workpiece 100 and the abrasive supply device 20. The moving means may have any configuration, but a mechanism that enables the abrasive jet nozzle 10 to move in some or all of the X direction, Y direction, Z direction, and θ direction can be employed.

[0025] The abrasive supply device 20 and the abrasive jet nozzle 10 are connected by a flexible pipe 30 and a rigid pipe 14 connected in series, and the abrasive is supplied from the abrasive supply device 20 to the abrasive jet nozzle 10 via these pipes. The flexible pipe 30 and the rigid pipe 14 are connected in series, with the flexible pipe 30 being provided on the abrasive supply device 20 side and the rigid pipe 14 being provided on the abrasive jet nozzle 10 side, integral with the abrasive jet nozzle 10. The rigid pipe 14 can be considered to be part of the abrasive jet nozzle 10.

[0026] Here, the flexible pipe means a pipe that can be flexibly deformed and can transport the abrasive without blocking the pipe even if it is deformed, and refers to a pipe using a tube made of resin such as urethane or nylon. In order to prevent the abrasive from being charged when it flows inside the pipe, the flexible pipe 30 may be made of a conductive tube. The material, inner diameter, thickness, length, etc. of the flexible pipe 30 are appropriately set so that the pipe is maintained without blocking when the abrasive jet nozzle 10 moves through the processed area of ​​the workpiece 100, and the elastic reaction force and inertial weight are not excessively large, and the flexible pipe 30 has durability against repeated deformation. For example, even in an apparatus that processes a large workpiece 100 of meter size, a flexible pipe 30 that is flexible and has a high degree of freedom in routing can be set.

[0027] The rigid piping is a piping made of a highly rigid material and has sufficient rigidity to not be substantially deformed even if it receives a force from the flexible piping 30 when the abrasive jet nozzle 10 moves. If it has the necessary rigidity, it can be made of a metal material such as copper or brass, or a resin material.

[0028] The abrasive supply device 20 as an abrasive supply section includes a tank 21 as a storage section for storing the abrasive 1, a screw 22 for sending the abrasive 1 toward an abrasive discharge section 24, and a motor 23 for rotating the screw 22. By rotating the screw 22 using the motor 23, the abrasive 1 stored in the tank 21 can be pushed out to the abrasive discharge section 24. The abrasive pushed out to the abrasive discharge section 24 is supplied (transported) to the abrasive jet nozzle 10 through the flexible piping 30 and the rigid piping 14.

[0029] The tank 21 serving as a storage section is provided with a powder level meter 26 that measures the level 27 of the upper surface of the abrasive in order to measure the amount of the abrasive stored. The powder level meter 26 is preferably one that can continuously measure the level 27 of the upper surface of the abrasive, and for example, a capacitance type or a radar type may be suitably used, but is not limited to these. The powder level meter 26 can measure the position (height) of the upper surface of the abrasive with high resolution, and can transmit the measurement results to the control section 25. When transmitting the measurement value to the control section, the measurement value may be subjected to filtering, averaging, or the like before transmission in order to suppress the influence of noise, etc.

[0030] The abrasive jet nozzle 10 includes an abrasive introduction chamber 11, a driving flow jet pipe 12, a mixing pipe 13 as a mixing chamber, and a rigid pipe 14 as an introduction pipe. Here, as described above, the rigid pipe 14 is a pipe having sufficient rigidity to not substantially deform even if it receives a force from the flexible pipe 30 when the abrasive jet nozzle 10 moves. The rigid pipe 14 as an introduction pipe has one end connected to the flexible pipe 30 and the other end fixed to the main body of the abrasive jet nozzle 10 so that the opening faces the abrasive introduction chamber 11.

[0031] One end of the driving flow injection pipe 12 is connected to an air tube (not shown), and the other end is inserted into the abrasive introduction chamber 11, and is fixed to the body of the abrasive injection nozzle 10 so that its tip is separated a predetermined distance from the mixing tube 13. The air tube is flexibly deformable like the flexible pipe 30, and the pipe line is not blocked even if it is deformed. The air tube is connected to a compressed gas supply source (not shown), and the driving flow injection pipe 12 has the function of ejecting an air flow toward the abrasive introduction chamber 11.

[0032] The mixing tube 13 as a mixing chamber constitutes the nozzle tip of the abrasive jet nozzle 10, and is a tube that mixes the abrasive introduced into the abrasive introduction chamber 11 from the rigid piping 14 and the air flow injected from the driving flow injection tube 12 inside the tube and injects it from the tip toward the workpiece 100. The mixing tube 13 is positioned so that its center line is aligned in the same line as the center line of the driving flow injection tube 12, and is fixed to the abrasive introduction chamber 11.

[0033] The control unit 25 is a computer for controlling the operation of the blast processing device 50, and includes a CPU, ROM, RAM, I / O ports, etc. The ROM stores an operation program for the blast processing device. The programs for executing various processes related to the abrasive jetting method or the method for supplying abrasive to the jet nozzle of this embodiment may be stored in a ROM like other operation programs, or may be loaded into a RAM from an external source via a network, or may be loaded into a RAM via a computer-readable recording medium on which the programs are recorded.

[0034] The I / O port is connected to an external device or a network, and can input and output data required for blast processing between an external computer, etc. The I / O port can also be connected to a monitor or an input device, and can display information on the operating status of the blast processing device 50 to an operator, and can receive commands from the operator.

[0035] The control unit 25 is connected to each part of the device, including the powder level meter 26, the motor 23, the movement mechanism of the abrasive jet nozzle 10, and the control mechanism for the pressure and flow rate of the air injected into the driving flow jet pipe 12, and transmits and receives control signals. The control unit 25 controls the operation of each of these parts to execute processing related to the entire blasting process. For convenience of illustration, only some of the control lines connecting the control unit 25 to each part are shown in Figure 1.

[0036] In this embodiment, the control unit 25 uses the measurement result of the powder level meter 26 to control the motor 23 that rotates the screw 22. In the method disclosed in Patent Document 2, the rotation of the motor is controlled based on the load on the motor, but since the fluctuation of the load on the drive source is minute, the detection accuracy of the change in the bulk specific gravity of the abrasive 1 at the bottom of the tank is insufficient. In this embodiment, by measuring the powder level using the powder level meter 26, it is possible to detect the change in the bulk specific gravity (bulk density) with high accuracy, and the mass of the abrasive supplied to the abrasive jet nozzle 10 per unit time can be controlled and stabilized with high accuracy.

[0037] The correlation between the level 27 of the top surface of the abrasive measured by the powder level meter 26 and the bulk specific gravity (bulk density) of the abrasive in the vicinity of the screw 22 is obtained in advance by experiments, simulations, etc., and stored in the control unit 25. Furthermore, the correlation coefficient between the rotation speed of the motor 23 and the volumetric flow rate of the abrasive discharged to the abrasive discharge unit 24 is obtained in advance by experiments, simulations, etc., and stored in the control unit 25. Then, using the two correlation coefficients obtained in advance and the measurement value of the powder level meter 26, the control unit 25 controls the rotation speed of the motor 23 so that the mass flow rate of the abrasive discharged to the abrasive discharge unit 24 is constant.

[0038] 5(a), when the level 27 of the upper surface of the abrasive is at a relatively high position, the bulk density of the abrasive near the screw 22 is high, so the rotation speed of the motor 23 that drives the screw 22 is made relatively small. On the other hand, when the level 27 of the upper surface of the abrasive is relatively low, the bulk density of the abrasive near the screw 22 is low, so the rotation speed of the motor 23 that drives the screw 22 is made relatively large. As shown in FIG. 5(a), it is preferable that the control unit 25 performs control so that the relationship between the measurement value of the powder level meter 26 and the screw rotation speed becomes linear.

[0039] By performing such control, even if the level 27 of the upper surface of the abrasive in the tank 21 fluctuates as the abrasive 1 is consumed or replenished, it is possible to stabilize the mass flow rate of the abrasive supplied to the abrasive jet nozzle 10. According to this embodiment, it is possible to provide a blast processing device 50 that can achieve high processing accuracy even if the amount of abrasive accumulated in the abrasive tank fluctuates.

[0040] [Embodiment 2] A schematic configuration of a blast processing device according to the second embodiment will be described with reference to Fig. 2. Portions common to the first embodiment will be illustrated with the same reference numerals, and description thereof will be simplified. The blast processing apparatus 60 of this embodiment is similar to that of embodiment 1 in that it is equipped with an abrasive jet nozzle 10 that jets abrasive to process the workpiece 100, an abrasive supply device 20 that supplies abrasive to the abrasive jet nozzle 10, and a control unit 25.

[0041] In this embodiment as well, the tank 21 is provided with a powder level meter 26 that measures the level 27 of the upper surface of the abrasive, and the measurement result is transmitted to the control unit 25. In the first embodiment, the control unit 25 controls the rotation speed of the motor 23 that rotates the screw 22 based on the measurement result of the powder level meter 26, but in this embodiment, the control unit 25 controls the distance between the abrasive jet nozzle 10 and the workpiece 100 based on the measurement result of the powder level meter 26.

[0042] As shown in Fig. 2, the blast processing device 60 includes a normal direction drive mechanism 33 for changing the distance between the abrasive jet nozzle 10 and the workpiece 100. Specifically, the normal direction drive mechanism 33 includes a ball screw 31 and a motor 32 for rotating the ball screw. A screw hole is provided in a support portion 34 of the abrasive jet nozzle 10, and the screw hole is engaged with the ball screw 31, so that the abrasive jet nozzle 10 can move up and down in response to the rotation of the motor 32. The control portion 25 can change the distance between the abrasive jet nozzle 10 and the workpiece 100 by controlling the motor 32.

[0043] As in the first embodiment, the correlation between the level 27 of the top surface of the abrasive measured by the powder level meter 26 and the bulk specific gravity (bulk density) of the abrasive in the vicinity of the screw 22 is obtained in advance by experiments, simulations, etc., and stored in the control unit 25. Furthermore, the correlation between the distance between the workpiece and the abrasive jet nozzle 10, and the grinding amount per unit time (grinding rate) is obtained in advance by experiments, simulations, etc., for each bulk specific gravity (bulk density) of the abrasive transported by the screw 22, and stored in the control unit 25.

[0044] Then, using the two correlation coefficients and the measurement value of the powder level meter 26, the control unit 25 controls the rotation of the motor 32 (the distance between the abrasive jet nozzle 10 and the workpiece 100) so that the grinding amount per unit time (grinding rate) for grinding the workpiece 100 is constant.

[0045] Specifically, as shown in FIG. 5(b), when the level 27 of the upper surface of the abrasive is in a relatively high position, the bulk density of the abrasive near the screw 22 is high, so the motor 32 is controlled so that the distance between the abrasive jet nozzle 10 and the workpiece 100 is relatively large. This is because the mass flow rate of the abrasive is high, so if the distance is not increased, the grinding rate will be excessive. Also, when the level 27 of the upper surface of the abrasive is in a relatively low position, the bulk density of the abrasive near the screw 22 is low, so the motor 32 is controlled so that the distance between the abrasive jet nozzle 10 and the workpiece 100 is relatively small. This is because the mass flow rate of the abrasive is low, so if the distance is not reduced, the grinding rate will be excessively small. As shown in FIG. 5(b), it is preferable that the control unit 25 controls the relationship between the measured value of the powder level meter 26 and the work distance (the distance between the abrasive jet nozzle 10 and the workpiece 100) to be nonlinear.

[0046] By performing such control, even if the level 27 of the upper surface of the abrasive in the tank 21 fluctuates as the abrasive 1 is consumed or replenished, the processing rate by the abrasive jet nozzle 10 can be stabilized. According to this embodiment, it is possible to provide a blast processing device 60 that can achieve high processing accuracy even if the amount of abrasive accumulated in the abrasive tank fluctuates.

[0047] [Embodiment 3] A schematic configuration of a blast processing device according to the third embodiment will be described with reference to Fig. 3. Portions common to the first embodiment will be illustrated with the same reference numerals, and description thereof will be simplified. The blast processing apparatus 70 of this embodiment is similar to that of embodiment 1 in that it is equipped with an abrasive jet nozzle 10 that jets abrasive to process the workpiece 100, an abrasive supply device 20 that supplies abrasive to the abrasive jet nozzle 10, and a control unit 25.

[0048] In this embodiment as well, the tank 21 is provided with a powder level meter 26 that measures the level 27 of the upper surface of the abrasive, and the measurement result is transmitted to the control unit 25. In the first embodiment, the control unit 25 controls the rotation speed of the motor 23 that rotates the screw 22 based on the measurement result of the powder level meter 26. In contrast, in this embodiment, the control unit 25 controls the scanning speed at which the abrasive jet nozzle 10 scans the workpiece 100 based on the measurement result of the powder level meter 26.

[0049] As shown in Fig. 3, the blast processing device 70 includes a horizontal drive mechanism 43 for scanning the abrasive jet nozzle 10 over the workpiece 100. Specifically, the horizontal drive mechanism 43 includes a ball screw 41 and a motor 42 for rotating the ball screw. A screw hole is provided in a support portion 44 of the abrasive jet nozzle 10, and the screw hole is engaged with the ball screw 41, so that the abrasive jet nozzle 10 can move horizontally in response to the rotation of the motor 42. The control portion 25 can change the scanning position and scanning speed of the abrasive jet nozzle 10 with respect to the workpiece 100 by controlling the motor 42.

[0050] As in the first embodiment, the correlation between the level 27 of the top surface of the abrasive measured by the powder level meter 26 and the bulk specific gravity (bulk density) of the abrasive in the vicinity of the screw 22 is obtained in advance by experiments, simulations, etc., and stored in the control unit 25. Furthermore, the correlation between the scanning speed of the abrasive jet nozzle 10 with respect to the workpiece and the grinding amount per unit time (grinding rate) is obtained in advance by experiments, simulations, etc., for each bulk density of the abrasive transported by the screw 22, and stored in the control unit 25. Then, using the two correlation coefficients and the measurement value of the powder level meter 26, the control unit 25 controls the rotational speed of the motor 42 (the scanning speed of the abrasive jet nozzle 10 relative to the workpiece 100) so that the grinding amount per unit time (grinding rate) for grinding the workpiece 100 is constant.

[0051] As shown in FIG. 6(a), when the level 27 of the upper surface of the abrasive is at a relatively high position, the bulk density of the abrasive near the screw 22 is high, so the motor 42 is controlled so that the scanning speed of the abrasive jet nozzle 10 relative to the workpiece 100 is relatively high. This is because the mass flow rate of the abrasive is high, so if the scanning speed is not increased, the grinding rate will be excessive. Also, when the level 27 of the upper surface of the abrasive is at a relatively low position, the bulk density of the abrasive near the screw 22 is low, so the motor 42 is controlled so that the scanning speed of the abrasive jet nozzle 10 relative to the workpiece 100 is relatively low. This is because the mass flow rate of the abrasive is low, so if the scanning speed is not reduced, the grinding rate will be too low. As shown in FIG. 6(a), it is preferable that the control unit 25 controls the relationship between the measurement value of the powder level meter 26 and the scanning speed to be linear.

[0052] By performing such control, even if the level 27 of the upper surface of the abrasive in the tank 21 fluctuates as the abrasive 1 is consumed or replenished, the processing rate by the abrasive jet nozzle 10 can be stabilized. According to this embodiment, it is possible to provide a blast processing device 70 that can achieve high processing accuracy even if the amount of abrasive accumulated in the abrasive tank fluctuates.

[0053] [Embodiment 4] A schematic configuration of a blast processing device according to the fourth embodiment will be described with reference to Fig. 4. Portions common to the first embodiment will be illustrated with the same reference numerals, and description thereof will be simplified. The blast processing apparatus 80 of this embodiment is similar to that of embodiment 1 in that it is equipped with an abrasive jet nozzle 10 that jets abrasive to process the workpiece 100, an abrasive supply device 20 that supplies abrasive to the abrasive jet nozzle 10, and a control unit 25.

[0054] In this embodiment as well, the tank 21 is provided with a powder level meter 26 that measures the level 27 of the upper surface of the abrasive, and the measurement result is transmitted to the control unit 25. In the first embodiment, the control unit 25 controls the rotation speed of the motor 23 that rotates the screw 22 based on the measurement result of the powder level meter 26. In contrast, in this embodiment, the control unit 25 controls the spray flow rate or spray pressure of the abrasive jet nozzle 10 based on the measurement result of the powder level meter 26.

[0055] As shown in FIG. 4, the blast processing device 70 includes an air flow control device 56 that controls the pressure or flow rate of the compressed air flowing through the driving flow injection pipe 12 of the abrasive injection nozzle 10 . The air flow control device 56 is equipped with a pipe 51 connected to the motive flow injection pipe 12, and a measuring instrument 55 that measures the pressure or flow rate of the compressed air flowing through the motive flow injection pipe 12. The air flow control device 56 further includes a flow rate control valve 52 that controls the flow rate of the compressed air flowing through the motive flow injection pipe 12, and a pressure control valve 53 that controls the pressure of the compressed air flowing through the motive flow injection pipe 12. The control unit 25 can control the flow rate and / or pressure of the compressed air flowing through the motive flow injection pipe 12 by operating the flow rate control valve 52 and / or the pressure control valve 53 by feedback control based on the measurement result of the measuring instrument 55.

[0056] As in the first embodiment, the correlation between the level 27 of the top surface of the abrasive measured by the powder level meter 26 and the bulk specific gravity (bulk density) of the abrasive in the vicinity of the screw 22 is obtained in advance by experiments, simulations, etc., and stored in the control unit 25. In addition, the correlation between the flow rate and / or pressure of the compressed air flowing through the driving flow injection pipe 12 and the grinding amount per unit time (grinding rate) is obtained in advance by experiments, etc., for each bulk specific gravity (bulk density) of the abrasive transported by the screw 22, and stored in the control unit 25. Then, using the two correlation coefficients and the measurement value of the powder level meter 26, the control unit 25 controls the flow control valve 52 and / or the pressure control valve 53 so that the grinding amount per unit time (grinding rate) for grinding the workpiece 100 is constant.

[0057] When the level 27 of the upper surface of the abrasive is at a relatively high position, the bulk density of the abrasive near the screw 22 is high. For this reason, as shown in Fig. 6(b), the pressure control valve 53 is controlled so that the pressure of the compressed air flowing into the driving flow injection pipe 12 of the abrasive injection nozzle 10 becomes relatively small. This is because the mass flow rate of the abrasive supplied is large, and if the injection pressure is not reduced, the grinding rate will become excessive. Alternatively, the flow control valve 52 can be controlled so that the flow rate of the compressed air flowing into the driving flow injection pipe 12 becomes relatively small.

[0058] Furthermore, when the level 27 of the upper surface of the abrasive is at a relatively low position, the bulk density of the abrasive near the screw 22 is low. For this reason, the pressure control valve 53 is controlled so that the pressure of the compressed air flowing into the driving flow injection pipe 12 of the abrasive injection nozzle 10 becomes relatively large. This is because, since the mass flow rate of the abrasive is small, the grinding rate will be too small unless the injection pressure is increased. Alternatively, the flow control valve 52 can be controlled so that the flow rate of the compressed air flowing into the driving flow injection pipe 12 becomes relatively large.

[0059] 6(b), it is preferable that the control unit 25 controls the relationship between the measurement value of the powder level meter 26 and the pressure of the compressed air flowing through the driving flow injection pipe 12 to be nonlinear. The control unit 25 may control so that only one of the pressure and the flow rate changes, or may control so that both change simultaneously.

[0060] By performing such control, even if the level 27 of the upper surface of the abrasive in the tank 21 fluctuates as the abrasive 1 is consumed or replenished, the processing rate by the abrasive jet nozzle 10 can be stabilized. According to this embodiment, it is possible to provide a blast processing device 70 that can achieve high processing accuracy even if the amount of abrasive accumulated in the abrasive tank fluctuates.

[0061] [Other embodiments] The present invention is not limited to the above-described embodiment, and many modifications are possible within the technical concept of the present invention. For example, the rotation control of the screw 22, the distance control between the abrasive jet nozzle 10 and the workpiece 100, the scanning speed control of the abrasive jet nozzle 10, and the air flow control of the compressed air may be arbitrarily combined to perform composite control.

[0062] In addition, when changing the distance between the workpiece and the abrasive jet nozzle or the scanning speed of the abrasive jet nozzle relative to the workpiece, it is not always necessary to fix the workpiece and move only the abrasive jet nozzle. As long as the relative positions of the workpiece and the abrasive jet nozzle can be changed, the workpiece may be moved and the abrasive jet nozzle may be fixed, or both may be moved.

[0063] The blast processing device according to the embodiment can be used, for example, in a processing process for uniformizing the thickness of a wafer. The thickness distribution of the wafer is measured in advance, and the amount of processing is increased in the thicker parts and decreased in the thinner parts, thereby uniformizing the thickness of the wafer. According to the embodiment, even if the amount of abrasive stored in the tank changes, the amount of processing per unit time does not change. Therefore, by changing the residence time or moving speed at each position on the wafer, the amount of processing at each position can be adjusted with high precision, and the thickness of the wafer can be uniformed with high precision.

[0064] In addition, the present invention can be widely used in the manufacture and processing of articles, not limited to polishing processes for planarizing the surfaces of wafers or substrates, but also for surface cleaning processes such as removing rust and coatings, shaping processes such as deburring, and roughening processes such as matte finish.

[0065] The present invention can also be realized by a process in which a program for implementing one or more functions of the embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more functions. [Explanation of symbols]

[0066] 1···Abrasive material / 10···Abrasive material injection nozzle / 11···Abrasive material introduction chamber / 12···Driven flow injection pipe / 13···Mixing pipe / 14···Rigid piping / 20···Abrasive material supply device / 21···Tank / 22···Screw / 23···Motor / 24···Abrasive material discharge section / 25···Control section / 26···Powder level meter / 27···Level of the top surface of the abrasive material / 30···Flexible piping / 31···Ball screw / 32···Motor / 33···Normal drive mechanism / 34···Support part / 41···Ball screw / 42···Motor / 43···Horizontal drive mechanism / 44···Support part / 50···Blast processing device / 51···Pipe / 52···Flow control valve / 53···Pressure control valve / 55···Measuring instrument / 56···Air flow control device / 60···Blast processing device / 70···Blast processing device / 80···Blast processing device / 100···Workpiece

Claims

1. a storage section for storing an abrasive; and an abrasive supply section including a sensor for measuring the height of an upper surface of the abrasive stored in the storage section; an injection nozzle that mixes the abrasive supplied from the abrasive supply unit with an air flow and injects the abrasive toward a workpiece; A control unit, The control unit is When the measurement value of the sensor is relatively large, the rotation speed of the screw that supplies the abrasive from the storage portion to the injection nozzle is relatively decreased, and when the measurement value of the sensor is relatively small, the rotation speed of the screw is relatively increased.

1. An abrasive jetting device comprising:

2. The sensor measures the height of an upper surface of the abrasive stored in the storage section by bringing a part of the sensor into contact with the abrasive.

2. The abrasive jetting device according to claim 1 .

3. The sensor is disposed between a wall surface of the storage portion and a center position of the storage portion, and at a position spaced a predetermined distance from the wall surface and a predetermined distance from the center position.

3. The abrasive jetting device according to claim 1 or 2.

4. The control unit acquires the measurement value of the sensor that has been subjected to filtering or averaging.

4. An abrasive jetting device according to claim 1, wherein the abrasive jetting device is a nozzle.

5. The sensor is capacitive or radar type.

5. An abrasive jetting device according to claim 1, wherein the abrasive jetting device is a nozzle.

6. The sensor directly measures the height of the upper surface of the abrasive stored in the storage section.

6. An abrasive jetting device according to claim 1, wherein the abrasive jetting device is a nozzle.

7. The control unit is A correlation between the measurement value of the sensor and the bulk density of the abrasive supplied from the screw toward the injection nozzle is stored in advance, Using the correlation, a rotation speed of the screw is controlled.

7. An abrasive jetting device according to claim 1, wherein the abrasive jetting device is a nozzle.

8. a storage section for storing an abrasive; and an abrasive supply section including a sensor for measuring the height of an upper surface of the abrasive stored in the storage section; an injection nozzle that mixes the abrasive supplied from the abrasive supply unit with an air flow and injects the abrasive toward a workpiece; A moving mechanism capable of moving a relative position between the injection nozzle and the workpiece; A control unit, The control unit controls the movement mechanism, When the measurement value of the sensor is relatively large, the distance between the injection nozzle and the workpiece is relatively increased, and when the measurement value of the sensor is relatively small, the distance between the injection nozzle and the workpiece is relatively decreased.

1. An abrasive jetting device comprising:

9. a storage section for storing an abrasive; and an abrasive supply section including a sensor for measuring the height of an upper surface of the abrasive stored in the storage section; an injection nozzle that mixes the abrasive supplied from the abrasive supply unit with an air flow and injects the abrasive toward a workpiece; A moving mechanism capable of moving a relative position between the injection nozzle and the workpiece; A control unit, The control unit controls the movement mechanism, When the measurement value of the sensor is relatively large, the scanning speed of the jet nozzle relative to the workpiece is relatively increased, and when the measurement value of the sensor is relatively small, the scanning speed of the jet nozzle relative to the workpiece is relatively decreased.

1. An abrasive jetting device comprising:

10. a storage section for storing an abrasive; and an abrasive supply section including a sensor for measuring the height of an upper surface of the abrasive stored in the storage section; an injection nozzle that mixes the abrasive supplied from the abrasive supply unit with an air flow and injects the abrasive toward a workpiece; A control unit, The control unit is When the measurement value of the sensor is relatively large, the pressure and / or the flow rate of the air flow is relatively decreased, and when the measurement value of the sensor is relatively small, the pressure and / or the flow rate of the air flow is relatively increased.

1. An abrasive jetting device comprising:

11. The height of the top surface of the abrasive stored in the storage section is measured by a sensor. When the measurement value of the sensor is relatively large, the rotation speed of the screw that supplies the abrasive from the storage section to the injection nozzle is relatively decreased, and when the measurement value of the sensor is relatively small, the rotation speed of the screw is relatively increased, and the abrasive is injected from the injection nozzle toward the workpiece.

1. An abrasive blasting method comprising the steps of:

12. The height of the top surface of the abrasive stored in the storage section is measured by a sensor. When the measurement value of the sensor is relatively large, the distance between the injection nozzle and the workpiece is relatively increased, and when the measurement value of the sensor is relatively small, the distance between the injection nozzle and the workpiece is relatively decreased.

1. An abrasive blasting method comprising the steps of:

13. The height of the top surface of the abrasive stored in the storage section is measured by a sensor. When the measurement value of the sensor is relatively large, the scanning speed of the jet nozzle relative to the workpiece is relatively increased, and when the measurement value of the sensor is relatively small, the scanning speed of the jet nozzle relative to the workpiece is relatively decreased.

1. An abrasive blasting method comprising the steps of:

14. The height of the top surface of the abrasive stored in the storage section is measured by a sensor. When the measurement value of the sensor is relatively large, the pressure and / or flow rate of the air flow mixed with the abrasive and sprayed toward the workpiece is relatively reduced, and when the measurement value of the sensor is relatively small, the pressure and / or flow rate of the air flow is relatively increased.

1. An abrasive blasting method comprising the steps of:

15. The abrasive is sprayed toward the workpiece by the abrasive spray method according to any one of claims 11 to 14 to process the workpiece. A method for producing an article.

16. A program capable of executing the abrasive blasting method according to any one of claims 11 to 14 by a computer.

17. A computer-readable recording medium having the program according to claim 16 recorded thereon.

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