JP2015136738A - Processing method and processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a processing defect such as a non-through hole and reduce confirmation operation of tool breakage which is time-consuming.SOLUTION: In each processing unit, a first step of directly detecting physical breakage of a tool at a time before the tool is brought into contact with a workpiece and a second step of detecting the physical breakage of the tool when the tool contacts with the workpiece are performed sequentially. Even when the breakage is detected in the second step, if the breakage is not detected in the first step performed in the next timing, the operation of the next processing unit is advanced. Even when the breakage is not detected in the first step, if the breakage is detected in the second step performed in the next timing, the processing operation is stopped, and a confirmation step of confirming the tool breakage is performed.

Description

  The present invention relates to a processing method and a processing apparatus used when, for example, drilling a printed board with a drill.

  Conventionally, there are the following two methods as a tool breakage detection function in a processing apparatus using a drill as a tool.

  One is to detect a physical breakage of the tool when the tool comes into contact with the workpiece during machining, and is called TBDD (Touch Broken Drill Detection). For example, as disclosed in Patent Document 1, when a drill contacts a printed circuit board to be processed, the contact is detected by, for example, a change in axial voltage generated on the rotor shaft of the spindle, and the detection position is detected. And the reference position are compared to determine the breakage length of the drill, and when it is greater than or equal to a predetermined value, the breakage of the drill is detected.

  The disadvantage of this method is that the breakage of the drill cannot be detected unless the drill actually contacts the printed circuit board. In other words, the fact that it cannot be detected without contact means that it cannot be stopped halfway during a series of drilling operations, so the drilling operation will always proceed once in a broken state, and there will be no unthrough holes. It is a point that occurs.

  Further, in the method of detecting the shaft voltage when the drill comes into contact with the printed circuit board, there is a possibility that it is erroneously detected as a broken state although it is rarely a broken state. In that case, an operation for confirming the broken state occurs in the confirmation station. The confirmation operation at the confirmation station is an operation that temporarily stops the machining operation, moves the drill to the position where the confirmation station exists, and accurately detects the drill diameter and drill length, but moves from the machining area. It takes time to complete the verification. In the case of erroneous detection, the machining tact time is reduced by the amount of confirmation time at the confirmation station, leading to a drawback that leads to a reduction in productivity.

  The other is called DBDD (Direct Broken Drill Detection), which directly detects physical breakage of the tool immediately before the tool contacts the workpiece during machining. For example, as disclosed in Patent Document 2, a light emitting unit that projects light and an optical sensor that receives light from the light emitting unit are mounted in a structure for holding a printed circuit board, and the optical axis connects the two. Drill breakage is detected by the degree of light shielding to the optical sensor by the drill positioned above.

  The disadvantage of this method is that, due to its structure, the optical axis between the light emitting part and the optical sensor is formed at a position above the tip of the drill by a certain amount. It is not possible to detect, and the drilling operation is continuously performed in a broken state, and a plurality of non-through holes are generated.

Japanese Patent Laid-Open No. 2001-341052 USP 3,912,925 Publication

  SUMMARY OF THE INVENTION Accordingly, the present invention has an object to prevent a processing failure such as a non-through hole and to reduce time-consuming tool breakage checking operation.

  In order to solve the above-described problem, in the machining method according to claim 1, for each machining unit, a first step of directly detecting a physical breakage of the tool at a time point before the tool contacts the workpiece; The second step of detecting the physical breakage of the tool when the tool comes into contact with the workpiece is performed before and after, and the first step is performed at the next timing even if the breakage is detected in the second step. If breakage is not detected at the next step, the operation of the next machining unit is advanced. If breakage is detected at the second step, which is performed at the next timing without detecting breakage at the first step, the machining operation is stopped. And a confirmation step for confirming the breakage of the tool.

  Further, in the processing method according to claim 2, in the processing method according to claim 1, when a breakage that cannot be detected in the next first step is detected in the second step, the first step is performed. It is characterized by the fact that the previous confirmation step is performed instead.

  Moreover, in the processing apparatus according to claim 3, when the tool contacts the workpiece, the first detection means for directly detecting the physical breakage of the tool before the tool contacts the workpiece. A second detection means for detecting a physical breakage of the tool, a first control means for operating the first detection means and the second detection means for each processing unit, and a breakage by the second detection means. If the first detection means that operates at the next timing does not detect breakage even if it is detected, the operation of the next processing unit is advanced, and the first detection means does not detect breakage at the next timing. And a third control unit for stopping the machining operation and confirming the breakage of the tool when the second detection unit that operates operates to detect a breakage.

  Further, in the processing apparatus according to claim 4, in the processing apparatus according to claim 3, when the third control unit detects breakage that the first detection unit cannot detect by the second detection unit. Is characterized in that the machining operation is stopped and the breakage is confirmed without waiting for the operation of the first detection means.

  According to the present invention, it is possible to prevent a machining defect such as a non-through hole and to reduce time-consuming tool breakage checking operation.

It is a flowchart in one Example of this invention. It is a figure which shows the structure of the drill processing apparatus of a present Example. It is a figure for demonstrating the structure of the bush in FIG. In the drill processing apparatus of a present Example, it is a figure which shows the displacement condition of the height of a drill tip at the time of repeating drilling operation | movement. It is a figure similar to FIG. It is a figure similar to FIG. It is a figure similar to FIG.

  FIG. 2 is a diagram showing a configuration of a drilling apparatus according to an embodiment of the present invention. In FIG. 2, reference numeral 1 denotes a printed circuit board to be processed, 2 a table on which the printed circuit board 1 is placed, 3 a drill for making a hole in the printed circuit board 1, and 4 a spindle for rotating the drill 3. . The table 2 and the spindle 4 are moved relative to each other so that the drill 3 comes to the drilling position of the printed circuit board 1. Reference numeral 5 denotes a pressure foot engaged with a tip end side of the spindle 12 via a cylinder (not shown), and reference numeral 6 denotes a bush attached to the lower end of the pressure foot 5 to press the upper surface of the printed circuit board 1. The pressure foot 5 can be lowered together with the spindle 12 until the bush 6 reaches the upper surface position of the printed circuit board 1. 7 is an axial voltage detector for detecting the axial voltage due to TBDD on the bush 6 side, 8 is an optical sensor for DBDD attached to the bush 6, and 9 is an overall control unit for controlling the entire apparatus. Program control processing It may be realized by an apparatus. The overall control unit 9 uses the outputs from the shaft voltage detector 7 and the optical sensor 8 in order to detect drill breakage by TBDD and DBDD, respectively.

  FIG. 3 is a view for explaining the structure of the bush in FIG. In FIG. 3, 8 is the above-mentioned optical sensor, and 10 is a light emitting unit, which are used for detecting drill breakage by DBDD.

  FIGS. 4-7 is a figure which shows the displacement condition of the height of a drill front end in the case of repeating drilling operation | movement in the drill processing apparatus of a present Example. In the figure, DB1 to DB3 are DBDD, and TB1 to TB3 are operation times of TBDD, respectively. DBDD and TBDD are repeated every time one drilling operation, which is a processing unit, is performed, but DBDD is performed at the timing before the descent starts to start the next drilling operation with the drill tip at the top, TBDD is performed during the subsequent descent.

  FIG. 1 is a flowchart for performing the drill breakage detection operation of FIGS. The above-described overall control unit 9 in FIG. 2 controls the whole so as to perform the operation of the flowchart of FIG. 1 every time one drilling operation is performed. First, the table 2 and the spindle 4 are relatively moved, and the drill 3 is moved to the next drilling position. Next, the breakage of the drill is detected by DBDD at the drilling position. If there is no breakage, the machining operation proceeds. If there is a breakage, the machining operation is stopped and the operation moves to the position of the confirmation station. After that, the breakage is confirmed at the confirmation station. If breakage is actually confirmed, the drill 3 is replaced, and then the position returns from the position of the confirmation station to the previous drilling position, and machining is started. If the breakage is not confirmed, it is a false detection by DBDD, so it returns from the position of the confirmation station to the previous drilling position and starts machining.

  When contacting the substrate after the start of processing, breakage detection by TBDD is performed, and if there is no breakage, it moves to the next drilling position and performs processing in the same flow. If there is a breakage in TBDD, it is determined whether the breakage can be detected by DBDD. Specifically, it may be determined whether the breakage length of the drill is greater than or equal to a predetermined value. This is because breakage determination cannot be performed by DBDD performed at the next timing unless the breakage length of the drill is equal to or greater than a predetermined value.

  If the determination by TBDD is such that breakage can be detected by DBDD, breakage is detected by DBDD at the timing of the next drilling, and if there is no breakage, it is a TBDD false detection and the next Move to the position and continue machining in the same flow as before. If there is breakage in DBDD, stop the machining operation and check for breakage at the confirmation station. Here, when breakage is not confirmed, it is a detection error of TBDD and DBDD, and it moves to the next drilling position and resumes processing. On the other hand, if breakage is also confirmed at the confirmation station, the drill 3 is replaced, and then machining is resumed from the same drilling position.

  If the determination of TBDD cannot be determined by DBDD performed at the next timing, the machining operation is stopped and the presence or absence of breakage is confirmed at the confirmation station. If there is no breakage here, it will be erroneously detected by TBDD, so move to the next drilling position and continue processing. On the other hand, if breakage can be confirmed at the confirmation station, the drill 3 is replaced and the machining is resumed from the same drilling position. The reason for re-execution at the same processing position is that, if there is a level of chipping that cannot be detected by DBDD, a non-through hole may occur.

  In this embodiment, as shown in FIG. 4, when a drill breakage occurs after TB2, breakage can be detected by DBDD before the next drilling operation starts, and the drilling operation proceeds in the broken state. Can be prevented. In addition, as shown in FIG. 5, when the chipping at a level that cannot be detected by DBDD after TB2 occurs, breakage can be detected by TBDD performed at the timing during the next drilling operation. Then, it can prevent that a non-through hole is generated. Further, as shown in FIG. 6, even if an erroneous detection occurs in TB2, if break detection is not performed by DBDD performed at the next timing, the break confirmation operation at the confirmation station which takes time is not performed, and the next operation is continued. Proceed to the machining operation. Thereby, useless time can be reduced and productivity is improved. As shown in FIG. 7, when a breakage that cannot be detected by DBDD performed at the next timing is detected in TB3, the process proceeds to a breakage confirmation operation at the confirmation station without performing DBDD.

In the present embodiment, the description has been given of the axial voltage detection method for TBDD and the optical detection method for DBDD, but other methods may be used.
Moreover, although the case of the drill was demonstrated as a tool, it is clear that this invention is applicable also to another tool.

1: Printed circuit board 2: Table 3: Drill 4: Spindle 5: Pressure foot 6: Bush 7: Shaft voltage detector 8: Optical sensor 9: Overall control unit 10: Light emitting unit

Claims (4)

  For each processing unit, the first step of directly detecting the physical breakage of the tool before the tool contacts the workpiece and the first step of detecting the physical breakage of the tool when the tool contacts the workpiece. The second step is performed before and after, and even if breakage is detected in the second step, if breakage is not detected in the first step performed at the next timing, the operation of the next machining unit is advanced, Even if no breakage is detected in the first step, if a breakage is detected in the second step, which is performed at the next timing, the machining operation is stopped and a confirmation step for confirming the breakage of the tool is performed. Processing method.   The processing method according to claim 1, wherein in the second step, when a breakage that cannot be detected in the next first step is detected, the confirmation step is performed without passing through the first step. Processing method.   First detection means for directly detecting the physical breakage of the tool before the tool contacts the work piece, and second detection for detecting the physical breakage of the tool when the tool comes into contact with the work piece Means, a first control means for operating the first detection means and the second detection means for each processing unit, and the second detection means to operate at the next timing even if the second detection means detects breakage. When breakage is not detected by the first detection means, the operation of the next machining unit is advanced, and the breakage is detected by the second detection means that operates at the next timing without detecting breakage by the first detection means. In some cases, the machining apparatus comprises third control means for stopping the machining operation and confirming the breakage of the tool. The processing apparatus according to claim 3, wherein the third control unit does not wait for the operation of the first detection unit when the second detection unit detects a break that cannot be detected by the first detection unit. A processing apparatus characterized in that processing operation is stopped and breakage is confirmed.

Images