Multi-level tool break detection using multi-mode sensing
    2.
    发明授权
    Multi-level tool break detection using multi-mode sensing 失效
    使用多模式感测的多级工具断点检测

    公开(公告)号:US4918427A

    公开(公告)日:1990-04-17

    申请号:US329044

    申请日:1989-03-27

    IPC分类号: B23Q17/09 G08B21/20

    摘要: A system and method for monitoring machine tool operations provides a multi-level tool break alarm and uses information from multiple sensors of different types. Signal processing and pattern recognition logic techniques are applied to a cutting process high frequency vibration signal to detect major tool breaks requiring prompt stoppage of the cut. False alarm resistant detection of minor tool breaks, for which the response may not be an immediate stop of the cutting process, is obtained with information from a low frequency vibration sensor, an axis drive current sensor, or an axis velocity sensor. A minor tool break alarm is generated when signal transients in both a high frequency and low frequency channel signal are in close time coincidence, and a major alarm when the high frequency channel transient is followed by a persisting mean vibration level shift.

    摘要翻译: 用于监控机床操作的系统和方法提供了多级工具中断报警,并且使用来自不同类型的多个传感器的信息。 信号处理和模式识别逻辑技术应用于切割过程高频振动信号,以检测需要及时停止切割的主要刀具断裂。 通过来自低频振动传感器,轴驱动电流传感器或轴速度传感器的信息,可以获得针对可能不立即停止切割过程的小型刀具断裂的防误报警检测。 在高频和低频信号信号中的信号瞬变处于紧密的时间一致时,产生小的工具中断报警,当高频信道瞬态随后是持续的平均振动电平偏移时,产生主要报警。

    Vibration-sensing tool break and touch detector optimized for machining
conditions
    3.
    发明授权
    Vibration-sensing tool break and touch detector optimized for machining conditions 失效
    针对加工条件优化的振动检测工具断裂和触摸检测器

    公开(公告)号:US4724524A

    公开(公告)日:1988-02-09

    申请号:US744083

    申请日:1985-06-12

    摘要: A Machine Tool Monitor detects significant cutting tool breakage and the first contact of an advancing tool to a workpiece, and does this by monitoring vibration signals produced by the machining of parts and interpreting patterns in these signals. Information from the part program improves the performance of the detector and optimizes it for the cutting conditions called for by the machine tool control. The analog channel gain of the monitor is adjusted and parameters controlling the digital pattern recognition logic are selected using part program information on machining parameters. The tool touch or tool break detection mode is selected by the part program.

    摘要翻译: 机床监视器检测到显着的切割刀具断裂和前进工具对工件的第一次接触,并通过监视由零件的加工产生的振动信号和这些信号中的解释模式来实现。 来自零件程序的信息提高了检测器的性能,并优化了机床控制所要求的切割条件。 调整监视器的模拟通道增益,并使用加工参数的零件程序信息来选择控制数字模式识别逻辑的参数。 通过零件程序选择工具触摸或刀具断点检测模式。

    Acoustic tool break detection system and method
    4.
    发明授权
    Acoustic tool break detection system and method 失效
    声学工具断裂检测系统及方法

    公开(公告)号:US4642617A

    公开(公告)日:1987-02-10

    申请号:US685005

    申请日:1984-12-21

    摘要: Substantial cutting condition changes that occur gradually, as opposed to the more usual sudden large change, are detected by setting upper and lower cutting noise mean level thresholds. When the mean cutting noise exceeds the upper threshold or stays below the lower threshold for a preset number of signal samples, a tool break alarm is generated. Techniques are given to reduce false alarms at the start and end of the cut and on runout on initial rough surface cuts. The system comprises an accelerometer or other sensor whose signal is preprocessed to attenuate lower frequency machinery noise and detect the signal energy in a band below 100 KHz, then sampled, and the digitized signal samples analyzed by pattern recognition logic.

    摘要翻译: 通过设置上下切割噪声平均水平阈值来检测到与逐渐变大的突然变化相反的逐渐发生的重大切割条件变化。 当平均切割噪声超过上限阈值或者对于预设数量的信号样本保持低于下限阈值时,产生刀具断裂报警。 给出了减少开始和结束时以及在初始粗糙表面切割时的跳动上的假警报的技术。 该系统包括加速度计或其他传感器,其信号被预处理以衰减较低频率的机械噪声并检测低于100KHz的频带中的信号能量,然后采样,并且通过模式识别逻辑分析数字化信号样本。

    Acoustic monitoring of cutting conditions to detect tool break events
    5.
    发明授权
    Acoustic monitoring of cutting conditions to detect tool break events 失效
    检测切割条件的声学监测以检测刀具断裂事件

    公开(公告)号:US4636780A

    公开(公告)日:1987-01-13

    申请号:US664188

    申请日:1984-10-24

    摘要: This tool break detection system relies on monitoring changes in the cutting noise itself, rather than detecting the tool fracture acoustic signal. A broken tool capable of damaging the workpiece is detected, and tool break events that do not affect cutting conditions are ignored. The signal from a sensor such as an accelerometer is preprocessed to attenuate low frequency machinery noise and detect the signal energy in a band below 100 KHz, then sampled, and the digitized signal samples analyzed by pattern recognition logic. Runout false alarms during rough surface cutting are prevented; after detection of an abrupt increase or decrease in signal level, the confirmation period to test for a persistent shift in mean level is set longer than the workpiece revolution period.

    摘要翻译: 该断屑检测系统依赖于监测切割噪声本身的变化,而不是检测工具断裂声信号。 检测到能够损坏工件的破损刀具,忽略不影响切削条件的刀具断裂事件。 来自诸如加速度计的传感器的信号被预处理以衰减低频机械噪声并检测低于100KHz的频带中的信号能量,然后采样,并且通过模式识别逻辑分析数字化信号样本。 防止粗糙表面切割过程中的跳动误报; 在检测到信号电平的突然增加或减小之后,将平均电平的持续移位测试的确认期间设定为比工件转动周期长。

    Acoustic detection of contact between cutting tool and workpiece
    6.
    发明授权
    Acoustic detection of contact between cutting tool and workpiece 失效
    切削刀具与工件之间接触的声学检测

    公开(公告)号:US4631683A

    公开(公告)日:1986-12-23

    申请号:US645203

    申请日:1984-08-29

    摘要: A system and method for monitoring vibrations of a machine tool metal-cutting tool insert and interpreting them to promptly detect the initial touch to the workpiece and signal the tool to stop advancing before marring the surface. The signal generated by a sensor such as an accelerometer is preprocessed to eliminate lower frequency machine noise and detect the energy in a higher frequency band, then sampled and analyzed by digital circuitry. In order to avoid false alarms on high amplitude spiky noise pulses generated by traverse operation of the machine tool, the tool touch alarm is delayed longer than the maximum duration of the noise pulses. Two techniques are given to ignore the noise spikes while still detecting the tool touch signal.

    摘要翻译: 一种用于监测机床金属切削刀具插入件的振动的系统和方法,并且解释它们以及时检测对工件的初始触摸并且在损坏表面之前发出信号以停止前进。 由诸如加速度计的传感器产生的信号被预处理以消除较低频率的机器噪声并且检测较高频带中的能量,然后由数字电路采样和分析。 为了避免由机床的横动操作产生的高振幅尖峰噪声脉冲的误报,工具触摸报警延迟时间比噪声脉冲的最大持续时间长。 给出两种技术来忽略噪声尖峰,同时仍然检测到工具触摸信号。

    Detection by automatic gain control features of gradual cutting tool
breakage
    10.
    发明授权
    Detection by automatic gain control features of gradual cutting tool breakage 失效
    通过自动增益控制检测功能,逐步切割刀具断裂

    公开(公告)号:US4806914A

    公开(公告)日:1989-02-21

    申请号:US46812

    申请日:1987-05-07

    摘要: A tool break detection system has an automatic gain control to adjust the analog signal channel gain and hold the cutting vibration signal at a desired average level. The AGC time constant is long enough that the detection of abrupt tool breaks and sudden large signal level transistions by the digital signature recognition logic is unaffected. However, the gradual decrease in signal level produced by a crumbly-type break would be removed by AGC action. In a system with a hardware AGC, crossing a high gain threshold resets gain to a low value and the resulting abrupt and persisting change in signal level is detected by the abrupt tool break logic. Another embodiment uses the gain command output by a software AGC and generates a break detected signal directly, without resetting the gain command, as gain rises above a high gain alarm level which is recalculated at the start of each cut.

    摘要翻译: 刀具断裂检测系统具有自动增益控制,以调整模拟信号通道增益并将切割振动信号保持在期望的平均水平。 AGC时间常数足够长,使得数字签名识别逻辑的突然工具断开检测和突发的大信号电平转移不受影响。 然而,通过AGC动作可以消除由脆弱型断路产生的信号电平的逐渐降低。 在具有硬件AGC的系统中,跨越高增益阈值将增益重置为低值,并且突然的工具断开逻辑检测到所产生的信号电平的突然和持续变化。 另一个实施例使用由软件AGC输出的增益指令,并且当增益高于在每次切断开始时重新计算的高增益警报水平时,直接生成中断检测信号而不复位增益命令。