JPH0520855U - Printed wiring board punching machine Spindle abnormality detection device - Google Patents

Abstract

(57) [Summary] [Purpose] In a printed wiring board drilling machine, abnormal vibration of the spindle system is measured in-process and in real time during drilling, facilitating maintenance and maintenance of the spindle system. And prevent the drill from breaking. [Arrangement] An AE sensor 4 attached to a workpiece pressing head portion 3 which is mounted in close contact with a main shaft 13 is attached, and an AE signal obtained from the AE sensor 4 is amplified to an appropriate level.
Through the full-wave rectifier circuit 23, a comparator 24 compares the preset threshold value with a preset threshold value, and outputs an abnormal value 27 to the abnormality detection circuit 25 when the preset threshold value is exceeded. The abnormality detection circuit 25 outputs the abnormal value 27 output from the comparator 24 and NC.
When the monitor signal 28 from the device 16 is obtained and the pulse output 31 from the pulse output timing generation circuit 25 is detected, the spindle 13 is determined to be abnormal, and the spindle abnormal signal 32 is output.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention is for a spindle system of a printed wiring board drilling machine, in which each contact portion of the spindle system (spindle, workpiece pressing cylinder portion, workpiece pressing head portion, cylinder, piston, ring, etc.) is worn or assembled. By monitoring the elastic wave (ACOUSTIC EMISSION, abbreviated as AE below) that causes abnormal vibration in the spindle system due to unsuitability or other factors, it is possible to reliably detect the abnormality of the spindle system and ensure maintenance and maintenance. This is a device for detecting abnormalities in the spindle of a printed wiring board puncher.

[0002]

[Prior Art]

 In printed wiring boards (hereinafter referred to as "substrates") used in various electronic devices, not only are many holes machined by drills, but also the diameter (usually 0.1 to 0.4 mm) for high-density mounting. ) Tends to become thinner, increasing the risk of breakage of the drill during drilling. As a method of preventing such drill breakage, various tools, machines, processing conditions, etc. are supported, but focusing on the relationship between spindle system abnormality and drill breakage, maintenance and maintenance are improved and periodic inspection, Moreover, the practical use of a highly reliable printed wiring board puncher spindle abnormality detection device that facilitates replacement and the like has not been proposed.

[0003]

[Problems to be solved by the device]

 This invention focuses on the relationship between spindle system abnormalities and drill breakage in a printed wiring board drilling machine, and focuses on the spindle system (spindle, workpiece clamp cylinder, workpiece clamp head, cylinder, piston, ring, etc.). ), The abnormal vibration of the spindle system that causes drill breakage due to wear of each contact part, improper assembly, or other factors is measured in-process and during drilling in real time. Abnormality of the spindle of a printed wiring board drilling machine that automatically detects and predicts abnormal vibrations of the spindle system to prevent breakage, thereby facilitating maintenance and maintenance of the spindle system and preventing drill breakage. It is to provide a detection device.

[0004]

[Means for Solving the Problems]

 Therefore, the present invention solves the above-mentioned problems of the prior art by providing an abnormality detecting device for a printed wiring board puncher main shaft described in the utility model registration claim.

[0005]

【Example】

 Hereinafter, the present invention will be described in detail with reference to FIGS. FIG. 1 shows a method of mounting the AE sensor 4 in an abnormality detecting device for a spindle of a printed wiring board punching machine according to an embodiment of the present invention and a schematic path of an AE elastic wave when an abnormal vibration occurs. This abnormality detecting device has an AE sensor 4 attached to a work-piece holding head portion 3 mounted in close contact with the spindle 13 of a printed wiring board punching machine, and an AE signal obtained from the AE sensor 4 has a proper value. The signal is inputted to the preamplifier 14 which is an amplifying means for amplifying to the level, and the AE signal amplified there is inputted to the signal processor 15. A drill 12 is fixedly mounted on the main shaft 13, and an AE sensor 4 is attached to a substrate 2 pressing head part 3 fixedly supported by a workpiece pressing cylinder part 11 that is in close contact with the outer periphery of the main shaft 13 and is in close contact therewith.

The AE sensor 4 is connected to the preamplifier 14 via a flexible lead wire. The signal processor 15 is connected to an NC device 16 which controls the printed wiring board puncher. FIG. 2 is a block diagram showing a detailed configuration inside the signal processing device 15 shown in FIG. The signal processing device 15 includes a bandpass filter 22 that extracts the high-frequency component of the AE signal obtained by further amplifying the output of the preamplifier 14 by the main amplifier 21, a full-wave rectifier circuit 23 that detects the signal from the bandpass filter 22, The comparator 24 receives the signal from the full-wave rectifier circuit 23, compares it with a preset threshold value, and outputs an abnormal value 27 when the preset threshold value is exceeded. Alternatively, for example, a specific wave rectifier circuit for extracting a specific frequency component is provided in addition to the full wave rectifier circuit 23 as disclosed in Japanese Patent Laid-Open No. 60-79261, and an arithmetic circuit at the input of these circuits is provided. Alternatively, the threshold value may be compared with a plurality of set threshold values.

The signal processing device 15 further has a timing generation circuit 26 for obtaining and outputting a monitoring signal 28 from the NC device 16 connected thereto. The timing of the monitoring signal 28 of the NC device 1 is ON when the spindle 13 starts to descend (the drill 12 is not in contact with the substrate 2 and the spindle 13 is rotating), and is turned OFF when the drilling is completed. When the monitoring signal 28 from 6 is obtained, a pulse output 31 is output from the timing generation circuit 26, and this pulse output 31 and the abnormal value 27 output of the comparator 24 are input to the abnormality detection circuit 25. The abnormality detection circuit 25 determines that the spindle 13 is abnormal when the abnormal value 27 output from the comparator 24 and the pulse output 31 from the timing generation circuit 26 are present, and outputs the spindle abnormality signal 32.

[0008] In operation, the contact portions of the main spindle system (spindle 13, workpiece pressing cylinder portion 11, workpiece pressing head portion 3, cylinder 5, piston 6, ring 9, etc.) are worn or improperly assembled, or When abnormal vibrations that cause drill breakage occur due to other factors, the abnormal vibrations become AE elastic waves 7, and the AE sensor 4 mounted on the work clamp head 3 mounted on the tip of the main shaft part. Propagate. The AE elastic wave 7 is converted into an electric signal by the AE sensor 4, and the AE signal output by the AE sensor 4 is amplified to an appropriate level by the preamplifier 14 and the main amplifier 21, and a band of about 100 to 300 KHZ is obtained. The frequency is detected by the pass filter 22 and the full-wave rectifier circuit 23, the necessary frequency component is extracted from the signal of the main amplifier 21 by the band-pass filter 22, is input to the comparator 24 through the full-wave rectifier circuit 23, and the preset threshold value, In the embodiment, when the AE signal level is exceeded, the comparator 24 outputs an abnormal value 27 to the abnormality detection circuit 25.

On the other hand, the timing generation circuit 26 receives the monitor signal 28 from the NC device 16 and outputs a pulse output 31. When the abnormal value 27 output of the comparator 24 and the pulse output 31 from the timing generation circuit 26 are input to the abnormality detection circuit 25, it is determined that the spindle 13 is abnormal, and the abnormality detection circuit 25 outputs the spindle abnormality signal 32. .. Due to this, (there are other causes of breakage of the drill), especially in the present invention, focusing on the relationship between the abnormality of the spindle system and the breakage of the spindle, wear or improper assembly of each contact part of the spindle system, or other The abnormal vibration of the spindle system that induces drill breakage can be measured in-process and in real time during drilling due to the above factors, and abnormal vibration of the spindle system is automatically detected and predicted to prevent drill breakage in advance. As a result, the spindle system can be easily maintained and maintained, and drill breakage can be prevented.

[0010]

[Effect of the device]

 As described above, according to the present invention, in the printed wiring board punching machine, focusing on the relationship between the spindle system abnormality and the drill breakage, the spindle system (spindle, workpiece clamp cylinder, workpiece clamp head, cylinder , Piston, ring, etc.) Abnormal vibration of the spindle system that causes drill breakage due to wear or improper assembly of each contact part, or other factors, is measured in the process and in real time during drilling. By automatically detecting abnormal vibrations of the spindle system to prevent drill breakage and predicting it, maintenance and maintenance of the spindle system can be facilitated and drill breakage can be prevented. It now provides an abnormality detection device for the main shaft of a drilling machine. FIG. 3 and FIG. 4 respectively show the waveform of the input part of the comparator 24 of the printed wiring board hole punching spindle abnormality detecting device of the present invention, the monitoring signal 28, the pulse output 31 and the spindle abnormality signal 32. In the graph, the AE signal level is as low as L0 in Fig. 3 and there is no abnormal value 27 output. In Fig. 4, the AE signal level is Ly and exceeds the preset threshold value Ls, and the abnormal value 27 output and pulse The output 31 outputs the spindle abnormal signal 32.

[Brief description of drawings]

FIG. 1 is a model diagram showing propagation of an AE elastic wave 7 when abnormal vibration occurs in an abnormality detecting device for a spindle of a printed wiring board puncher according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration inside a processing main body 15 shown in FIG.

3 is a graph showing the waveform of the input section of the comparator 24 of FIG. 4, the monitoring signal 28, the pulse output 31 and the spindle abnormality signal 32, respectively. The AE signal level is low at L0 and the spindle abnormality signal 32 is output. Indicates the absence.

4 is a graph showing the waveform of the input part of the comparator 24 of FIG. 4, the monitor signal 28, the pulse output 31 and the spindle abnormal signal 32, respectively, in which the AE signal level exceeds Ly and a preset threshold value Ls. In this state, the spindle abnormal signal 32 is present.

[Explanation of symbols]

 1. ． Main body of printed wiring board puncher 2. ． Printed wiring board (substrate) 3. ． Workpiece retainer head section 4. ． AE sensor 7. ． AE elastic wave 12. ． Drill 13. ． Spindle 14, 21. ． Amplifier (amplifying means) 15. ． Signal processing device 16. ． NC device 22. ． Band pass filter 23. ． (Full wave) rectifier circuit 24. ． Comparator 25. ． Abnormality detection circuit 26. ． Timing generation circuit 27. ． Outlier 28. ． Supervisory signal 31. ． Pulse output 32. ． Spindle error signal

Claims (1)

[Scope of utility model registration request] 1. A main shaft supported by a main body of a printed wiring board punching machine, an AE sensor mounted on a workpiece pressing head mounted in close contact with the main shaft, and an AE signal obtained from the AE sensor to a proper degree. Amplification means for amplifying to a level, a bandpass filter for extracting a high frequency component of the amplified AE signal, a rectifier circuit for detecting a signal from the bandpass filter, and a set threshold value by inputting a signal from the rectifier circuit. In comparison with the comparator that outputs an abnormal value when the set threshold value is exceeded, the abnormal value output from the comparator, the drill mounted on the spindle and the printed wiring board are in non-contact state, and A timing generation circuit that outputs a pulse output by inputting a monitoring signal from an NC device that is output when the spindle descends during rotation and is turned off when hole drilling is completed, and an abnormal value output of the comparator. An abnormality detection device of a printing wiring board drilling machine main shaft and having a, an abnormality detecting circuit for outputting an abnormality and to the main axis abnormal signal of the main shaft when a pulse output from the timing generation circuit.