Processing equipment

Abstract

To provide a processing device that can detect a degree of abrasions of a polishing tool whose shape is hardly varied by abrasion.SOLUTION: A processing device 1 comprises: a polishing tool 5 which is abraded by contacting an object to be ground so that mass thereof varies; a mass sensor 14 (measurement part) that measures the mass of the polishing tool 5; and an abrasion determining part 33 that estimates a degree of abrasions of the polishing tool 5 on the basis of a measurement result from the mass sensor 14 (measurement part). One of the polishing tool 5 and the object 21 to be ground is mounted on a robot arm 2, and is pressed against the other of the polishing tool 5 and the object to be ground during polishing work.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a processing device using an abrasive tool. [Background technology]

[0002] Patent Document 1 describes a technique for taking an image of a grinding wheel with a television camera and calculating the amount of wear of the grinding wheel based on the image data. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-202771 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the technique of Patent Document 1, it is difficult to detect the degree of wear of a polishing tool whose shape is hardly changed by wear.

[0005] An object of the present invention is to provide a processing device capable of detecting the degree of wear of a polishing tool that undergoes little change in shape due to wear. [Means for solving the problem]

[0006] The processing device according to the present invention comprises: a polishing tool whose mass changes as it comes into contact with the workpiece; a measuring unit for measuring the mass of the polishing tool; a wear determination unit that estimates a degree of wear of the polishing tool based on the measurement results of the measurement unit; and With death, the wear determination unit estimates a degree of wear of the polishing tool based on the data stored in the mass change database and the measurement results of the measurement unit; and the mass change database stores readably first data indicating the mass of the polishing tool relative to the polishing time and second data indicating the polishing amount of the workpiece relative to the polishing time; The first data and the second data are stored in the mass change database for each combination of the material of the polishing tool and the material of the workpiece. do. [Effects of the Invention]

[0007] According to the present invention, it is possible to detect the degree of wear of a polishing tool that undergoes little change in shape due to wear. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating an example of a processing device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing the configuration of a processing device. [Figure 3] 10 is a flowchart of a polishing operation. [Figure 4] FIG. 10 is a simplified diagram showing a mass change database for a polishing tool. [Figure 5] FIG. 10 is a diagram showing the relationship between tool mass and polishing time, and between polishing amount and polishing time. [Figure 6] FIG. 10 is a diagram showing a processing device according to a first modified example. [Figure 7] FIG. 10 is a diagram showing a processing device according to a second modified example. [Figure 8] FIG. 10 is a diagram showing a processing device according to a third modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 is a diagram showing an example of a processing apparatus 1 according to an embodiment of the present invention. Fig. 2 is a block diagram showing the configuration of the processing apparatus 1. Fig. 3 is a flowchart of a polishing operation.

[0010] As shown in FIG. 1 , the processing apparatus 1 of this embodiment includes a polishing tool attachment 3 fixed to the tip of a robot arm 2 (a polishing load-applying body), a tool holder 4 attached to the polishing tool attachment 3, and a polishing tool 5 held by the tool holder 4. The robot arm 2 has a first arm 6 and a second arm 7. One end of the first arm 6 is swingably connected to a base 10 via a first joint 8, and the other end of the first arm 6 is connected to one end of the second arm 7 via a second joint 11. The second arm 7 is swingable around the second joint 11, with the second joint 11 serving as the swing center. The base 10 is fixed to an environment (not shown) (e.g., a factory floor, a robot arm holder, or a portion other than the robot arm 2).

[0011] 1, the polishing tool mounting unit 3 has a side plate 12 and a bottom plate 13 integrally formed with the lower end of the side plate 12 so as to be perpendicular to the side plate 12. The side plate 12 is fixed to the other end of the second arm unit 7 (the tip of the robot arm 2) with the bottom plate 13 facing downward and perpendicular to the longitudinal direction of the second arm unit 7. A mass sensor 14 (e.g., a load cell) serving as a measurement unit is attached to the upper surface of the bottom plate 13 of the polishing tool mounting unit 3. The polishing tool 5 held by the tool holder 4 is positioned above the mass sensor 14 in a manner that allows it to be moved toward or away from the mass sensor 14.

[0012] As shown in FIG. 1 , the tool holder 4 is slidable up and down along the side plate 12 of the polishing tool mounting part 3. As the tool holder 4 moves upward, a gap is created between the tool body 15 of the polishing tool 5 and the mass sensor 14, and the tool holder 4 moves upward until it abuts against a stopper projection 16 on the side plate 12. Furthermore, the tool holder 4 is able to slide along the side plate 12 of the polishing tool mounting part 3 without coming off the side plate 12 of the polishing tool mounting part 3 by engaging a plate-shaped slider 17 with a guide groove (e.g., a dovetail groove) (not shown) in the side plate 12 of the polishing tool mounting part 3. Holding bands 18 formed at two locations, one above the other, of the tool holder 4 securely hold the rod-shaped tool body 15 of the polishing tool 5, allowing the tool holder 4 and the tool body 15 of the polishing tool 5 to move together.

[0013] As shown in FIG. 1, a polishing tool 5 (e.g., a belt sander) includes an endless belt having abrasive grains fixed to its surface, the abrasive material 20 (e.g., a sanding belt) wound around a drive roller and a driven roller (not shown). The drive roller is rotated by a motor M1, causing the abrasive material 20 to rotate. The rotating abrasive material 20 is pressed against a workpiece 21, causing the abrasive material 20 to polish the workpiece 21. The polishing tool 5 is configured such that an imaginary line 22 connecting the center C1 of the drive roller and the center C2 of the driven roller, between which the abrasive material 20 is wound, intersects at an acute angle with the longitudinal direction of the tool body 15 (the vertical direction in FIG. 1). This results in a machining resistance (grinding resistance) that acts in a direction that lifts the tool body 15. As a result, during grinding, the polishing tool 5 moves upward along the side plate 12 of the polishing tool attachment part 3, and the tool body 15 is separated from the mass sensor 14. On the other hand, when the abrasive 20 is separated from the workpiece 21, the polishing tool 5 is seated on the mass sensor 14 due to its own weight, and the mass is measured by the mass sensor 14.

[0014] As shown in FIG. 1, the workpiece 21 is exemplified as a plate-shaped body, but is not limited to this and may be any shape that can be ground by the abrasive 20, and is held by a workpiece holder (not shown) or the like so that it does not move due to grinding resistance.

[0015] As shown in FIGS. 2 and 3 , when the polishing operation is started and the mass of the polishing tool 5 is measured by the mass sensor 14 (step S1), the measurement result (mass data) is input to the wear determination unit 23. The wear determination unit 23 compares the mass history measured by the mass sensor 14 with data stored in the mass change database 24 (step S2), estimates the degree of wear of the polishing tool 5, and whether the polishing tool 5 should be replaced (step S3), and outputs the estimated result as a wear determination signal to the control unit 25. Based on the signal from the wear determination unit 23, the control unit 25 controls the operation of the robot arm 2 (operation of the motors M1 and M2) to adjust the relative positions of the abrasive 20 and the workpiece 21, bringing the polishing tool 5 into contact with the workpiece 21 at an appropriate polishing load. The control unit 25 also controls the rotation speed of the abrasive 20 based on the signal from the wear determination unit 23. Furthermore, when a signal indicating the time to replace the polishing tool 5 is output from the wear determination unit 23, the control unit 25 outputs a control signal to the notification unit 26 based on the signal from the wear determination unit 23, and the notification unit 26 visually and / or audibly notifies the operator, etc., that it is time to replace the polishing tool 5 via the monitor and / or speaker of the notification unit 26. Furthermore, when a signal indicating the time to replace the polishing tool 5 is output from the wear determination unit 23, the control unit 25 outputs a control signal to the robot arm 2 based on the signal from the wear determination unit 23, and separates the abrasive 20 of the polishing tool 5 from the workpiece 21, thereby stopping the operation of the polishing tool 5. As a result, the processing apparatus 1 becomes able to replace the polishing tool 5 with a new polishing tool 5 (step S4). Note that this polishing tool 5 replacement operation does not necessarily have to be performed by the operator, but may be performed automatically by a polishing tool replacement device (not shown).

[0016] When the wear determination unit 23 estimates that the degree of wear of the polishing tool 5 has not reached the time to replace the polishing tool 5 (step S3), it outputs the estimation result to the control unit 25. The control unit 25 outputs a control signal to the robot arm 2 based on the signal from the wear determination unit 23, and controls the contact state between the abrasive 20 of the polishing tool 5 and the workpiece 21 by the robot arm 2 so that the polishing operation can be continued with a polishing force according to the degree of wear (step S5).

[0017] The control unit 25 also determines whether the polishing work has been completed (step S6), and if it determines that the polishing work has not been completed, continues the polishing work. When the amount of grinding of the workpiece 21 measured by the polishing amount detection sensor 27 reaches a preset amount, the control unit 25 determines that the polishing work has been completed (step S6), and ends the polishing work.

[0018] 4 is a simplified diagram showing the mass change database 24 of the polishing tool 5. As shown in this Fig. 4, the mass change database 24 stores multiple patterns of data 28a-28c in a readable manner for each combination of the material of the abrasive 20 (for example, a sanding belt as a coated abrasive) and the material of the workpiece 21. The data 28a-28c for each pattern stored in the mass change database 24 was obtained in advance by experiment, and serves as reference data for comparison with the data measured by the mass sensor 14.

[0019] FIG. 5 is a diagram showing the relationship between the tool mass, the polishing time, and the relationship between the polishing amount and the polishing time, and is a diagram showing the data stored in the mass change database 24 shown in FIG. 4. In this FIG. 5, the curve 30 shown by the solid line shows the history of the mass change of the polishing tool 5 with respect to the polishing time. The horizontal axis represents the polishing time, and the vertical axis represents the mass of the polishing tool 5. And the data of the mass of the polishing tool 5 with respect to the polishing time in the curve 30 shown by this solid line is stored in the mass change database 24 as the first data. Further, in FIG. 5, the curve 31 shown by the broken line is a diagram showing the history of the change in the polishing amount with respect to the polishing time. The horizontal axis represents the polishing time, and the vertical axis represents the polishing amount. And the data of the polishing amount with respect to the polishing time in the curve 31 shown by this broken line is stored in the mass change database 24 as the second data. Note that the first data is such that when the amount of material adhesion of the workpiece 21 clogged (adhered) between the abrasive grains of the polishing tool 5 increases more than the amount of abrasive grain dropout of the polishing tool 5, the mass of the polishing tool 5 increases. Also, the second data is such that the rate of change of the polishing amount decreases with the passage of the polishing time, and approaches a substantially constant polishing amount in the vicinity of the polishing time when the history of the mass change of the polishing tool 5 changes from decreasing to increasing.

[0020] For example, as shown in FIG. 5, the wear determination unit 23 calculates a mass change rate (Δ1) based on the history of the change in the mass of the polishing tool 5 measured by the mass sensor 14 (the tool mass m2 corresponding to the polishing time t2 at the time of measuring the mass of the polishing tool 5 and the tool mass m1 corresponding to the polishing time t1 at the immediately preceding measurement of the mass of the polishing tool 5) (Δ1 = (m1 - m2) / (t1 - t2)). Next, the wear determination unit 23 calculates a polishing amount change rate (Δ2) based on the history of the change in the polishing amount in the mass change database 24 (the values of the polishing amount n1 corresponding to the polishing time t1 and the polishing amount n2 corresponding to the polishing time t2) (Δ2 = (n1 - n2) / (t1 - t2)). Next, when the mass change rate (Δ1) is a negative value (when the mass decreases with the passage of the polishing time), and the polishing amount change rate (Δ2) is a positive value and the polishing amount change rate (Δ2) is within a predetermined threshold S1 to S2 (S1 < Δ2 < S2), the wear determination unit 23 estimates that the replacement time of the polishing tool 5 has been reached (step S3 in FIG. 3).

[0021] Further, as shown in FIG. 5, the wear determination unit 23 calculates a mass change rate (Δ1) based on the history of the change in the mass of the polishing tool 5 measured by the mass sensor 14 (the tool mass m2 corresponding to the polishing time t2 at the time of measuring the mass of the polishing tool 5 and the tool mass m1 corresponding to the polishing time t1 at the time of the immediately preceding measurement of the mass of the polishing tool 5) (Δ1 = (m1 - m2) / (t1 - t2)). Then, when the mass change rate (Δ1) is a negative value (when the mass decreases as the polishing time elapses) and the mass change rate (Δ1) falls within a predetermined threshold S3 to S4 (S3 < Δ1 < S4), the wear determination unit 23 may estimate that the replacement time of the polishing tool 5 has been reached.

[0022] Further, when the mass of the polishing tool 5 measured by the mass sensor 14 becomes less than or equal to a preset value, the wear determination unit 23 may estimate that the wear degree of the polishing tool 5 has reached the replacement time of the polishing tool.

[0023] As described above, in the processing apparatus 1 according to the present embodiment, the mass of the polishing tool 5 is measured by the mass sensor 14 (measurement unit), and the wear determination unit 23 estimates the wear degree of the polishing tool 5 from the measurement result of the mass sensor 14. Therefore, it is possible to detect the wear degree of the polishing tool 5 with little shape change due to wear.

[0024] Further, in the processing apparatus 1 according to the present embodiment, the mass of the polishing tool 5 is measured by the mass sensor 14, and the wear determination unit 23 estimates the wear degree of the polishing tool 5 based on the measurement result of the mass sensor 14. Therefore, the replacement time of the polishing tool 5 can be determined. Note that the replacement of the polishing tool 5 includes the replacement of only the abrasive 20 of the polishing tool 5.

[0025] Furthermore, since the processing apparatus 1 according to this embodiment can estimate the degree of wear of the polishing tool 5 using the wear determination unit 23, it is possible to control the operation of the robot arm 2 (polishing load applying body) based on the estimation results of the wear determination unit 23, and to control the polishing load acting on the contact portion between the abrasive 20 of the polishing tool 5 and the workpiece 21 to an optimal state according to the degree of wear of the abrasive 20 of the polishing tool 5.

[0026] Furthermore, since the processing apparatus 1 according to this embodiment can estimate the degree of wear of the polishing tool 5 using the wear determination unit 23, it becomes possible to control the rotation speed (polishing speed) of the abrasive 20 of the polishing tool 5 based on the estimation result of the wear determination unit 23.

[0027] Furthermore, the processing device 1 according to this embodiment can determine the replacement time for the polishing tool 5, and therefore can promote automation of polishing work.

[0028] (Variation 1) Fig. 6 is a diagram showing a first modified example of the processing device 1. In the description of the processing device 1 shown in Fig. 6, parts common to the configuration of the processing device 1 shown in Fig. 1 are given the same reference numerals, and overlapping descriptions will be omitted.

[0029] As shown in Fig. 6, a workpiece 21 is held by a bifurcated hand unit 32 located at the tip of the robot arm 2, and a polishing tool 5 is attached to a polishing tool attachment unit 3 fixed to the environment via a tool holder 4. The processing device 1 shown in Fig. 6 is capable of controlling the contact load (polishing load) between the abrasive 20 of the polishing tool 5 and the workpiece 21 by controlling the position of the hand unit 32 of the robot arm 2.

[0030] The polishing tool mounting unit 3 has side plates 12 positioned parallel to the vertical direction (Z direction) and a bottom plate 13 positioned parallel to the horizontal direction (X direction), and a mass sensor 14 fixed on the bottom plate 13. The polishing tool mounting unit 3 holds a tool holder 4 so that it can slide up and down along the side plates 12, and stopper protrusions 16 formed on the side plates 12 regulate the upper limit position of the tool holder 4. The tool holder 4 holds the polishing tool 5 with gripping bands 18 positioned at two locations, one above the other, and is able to slide together with the tool body 15 of the polishing tool 5. When the abrasive 20 of the polishing tool 5 and the workpiece 21 separate and the polishing load no longer acts on the abrasive 20 of the polishing tool 5, the tool holder 4 descends along the side plates 12 of the polishing tool mounting unit 3 under its own weight, causing the tool body 15 of the polishing tool 5 to seat on the mass sensor 14. As a result, the processing apparatus 1 according to this modification can measure the mass of the polishing tool 5 with the mass sensor 14.

[0031] The processing device 1 according to this modification can obtain the same effects as those of the processing device 1 described with reference to FIGS.

[0032] (Variation 2) FIG. 7 illustrates a second modification of the processing apparatus 1. In the processing apparatus 1 shown in FIG. 7, a polishing tool 5 is attached to a polishing tool attachment 3 that is fixed to the environment. A workpiece (not shown) is pressed against the abrasive 20 of the polishing tool 5. The polishing tool attachment 3 is formed with a tool attachment groove 33 that accommodates the tool body 15 of the polishing tool 5. The lower end of the tool body 15 of the polishing tool 5 is rotatably supported on the polishing tool attachment 3 by a rotation support shaft 34, and is tilted obliquely forward by a rear wall surface 35 of the tool attachment groove 33. Furthermore, when the workpiece is not in contact with the abrasive 20 (when no polishing load is applied), the tool body 15 of the grinding tool 5 rotates forward (counterclockwise) around the rotation support shaft 34 due to its own weight and abuts against a mass sensor 14 fixed to a front wall surface 36 of the tool attachment groove 33. As a result, the mass of the polishing tool 5 is measured by the mass sensor 14. On the other hand, during polishing work, the polishing tool 5 rotates clockwise around the rotation support shaft 34 as the abrasive 20 receives the polishing load, and moves away from the mass sensor 14, maintaining its posture in contact with the rear wall surface 35 of the tool attachment groove 33. The polishing tool 5 may be attached via a tool holder 4 to a polishing tool attachment part 3 fixed to a robot arm.

[0033] The processing device 1 according to this modification can obtain the same effects as those of the processing device 1 described with reference to FIGS.

[0034] (Variation 3) Fig. 8 is a diagram showing a modified example 3 of the processing apparatus 1. The processing apparatus 1 shown in Fig. 8 has the same configuration as the polishing tool attachment part 3, tool holder 4, and polishing tool 5 of the processing apparatus 1 shown in Fig. 6, and the polishing tool 5 is attached via the tool holder 4 to the polishing tool attachment part 3 that is fixed to the environment.

[0035] 8 is configured so that the polishing work of the workpiece (not shown) is performed by the polishing tool 5 in a state where the workpiece (not shown) sliding in the X direction is pressed against the abrasive 20 of the polishing tool 5 with a predetermined polishing load. In this case, the polishing tool 5 is moved upward (in the Z direction) together with the tool holder 4 by the polishing load acting on the abrasive 20, and moves away from the mass sensor 14.

[0036] Meanwhile, in the processing apparatus 1, when the workpiece (not shown) is separated from the abrasive 20 of the polishing tool 5 and no polishing load is acting on the abrasive 20 of the polishing tool 5, the tool body 15 of the polishing tool 5 falls under its own weight along the side plate 12 of the polishing tool attachment part 3 together with the tool holder 4, and the tool body 15 of the polishing tool 5 sits on the mass sensor 14. As a result, the mass of the polishing tool 5 is measured by the mass sensor 14. The polishing tool 5 may also be attached to the polishing tool attachment part 3 fixed to the robot arm via the tool holder 4.

[0037] The processing device 1 according to this modification can obtain the same effects as those of the processing device 1 described with reference to FIGS.

[0038] (Other variations) The processing apparatus 1 of the above embodiment and each modified example uses a belt sander as an example of the polishing tool 5, but is not limited to this and can also be applied to cases where a cloth belt for buffing, whose mass changes when it comes into contact with the workpiece 21, is used instead of a sanding belt. Furthermore, the robot arm 2 is not limited to the configuration shown in FIGS. 1 and 6, and various configurations may be used depending on the situation at the polishing site. [Explanation of symbols]

[0039] 1 Processing equipment 2. Robot arm (polishing load applying body) 5 Polishing tools 14 Mass sensor (measurement section I 21 Workpiece 23 Wear determination unit 24 Mass Change Database 25 Control Unit 26. Information Department

Claims

1. a polishing tool whose mass changes as it comes into contact with the workpiece; a measuring unit for measuring the mass of the polishing tool; a wear determination unit that estimates a degree of wear of the polishing tool based on the measurement results of the measurement unit; and and the wear determination unit estimates a degree of wear of the polishing tool based on the data stored in the mass change database and the measurement results of the measurement unit; and the mass change database stores readably first data indicating the mass of the polishing tool relative to a polishing time and second data indicating the polishing amount of the workpiece relative to the polishing time; The first data and the second data are stored in the mass change database for each combination of the material of the polishing tool and the material of the workpiece.

2. the wear determination unit further estimates a degree of wear of the polishing tool based on a history of changes in mass of the polishing tool measured by the measurement unit. The processing device according to claim 1 .

3. the measuring unit comes into contact with the polishing tool and measures the mass of the polishing tool when the polishing tool and the workpiece are separated from each other. The processing device according to claim 1 or 2.

4. One of the polishing tool and the workpiece is attached to a polishing load-applying body, and is pressed against the other of the polishing tool and the workpiece during polishing work. The processing device according to claim 1 or 2.

5. a control unit for controlling the operation of the polishing load-applying body; the control unit controls the operation of the polishing load-applying body based on a signal from the wear determination unit. The processing device according to claim 4.

6. When the wear determination unit determines that the degree of wear of the polishing tool has reached the time for replacement, the control unit outputs a control signal to a notification unit, and causes the notification unit to notify an operator that the polishing tool has reached the time for replacement. The processing device according to claim 5.

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