Abstract: A welding system using a purge plug for data acquisition. In one example, a purge plug includes purge plug component having a sealing structure. The sealing structure is configured to abut a surface of a hollow device and to form a seal between the sealing structure and the hollow device. The purge plug also includes a sensor at least partly disposed in the purge plug component, the sealing structure, or some combination thereof.

Abstract: A welding system using a purge plug for data acquisition. In one example, a purge plug includes purge plug component having a sealing structure. The sealing structure is configured to abut a surface of a hollow device and to form a seal between the sealing structure and the hollow device. The purge plug also includes a sensor at least partly disposed in the purge plug component, the sealing structure, or some combination thereof. The purge plug component is configured to be disposed on a workpiece having the hollow device to purge an undesired gas from the workpiece.

Abstract: A welding system using a purge plug for data acquisition. In one example, a purge plug includes purge plug component having a sealing structure. The sealing structure is configured to abut a surface of a hollow device and to form a seal between the sealing structure and the hollow device. The purge plug also includes a sensor at least partly disposed in the purge plug component, the sealing structure, or some combination thereof.

Abstract: The secondary ignition circuit of a spark ignited internal combustion engine is analyzed to identify the location of faulty portions of the circuit, the circuit having an induction coil for generating sparking voltage pulses repetitively, and a distributor for cyclically distributing the voltage pulses to respective spark plugs in a predetermined order. The peak amplitude of respective voltage pulses of one polarity developed at a single point in the secondary ignition circuit for respective spark plugs in each engine cycle is measured to produce measurement signals systematically related thereto. A comparison signal is derived that is systematically related to the average peak amplitude of voltage pulses of the one polarity developed for all spark plugs. Successive measurement signals are compared with the comparison signal, and a fault is indicated when a measurement signal differs from the comparison signal by more than a predetermined differential.

Abstract: An acoustic tachometer for diesel engines includes a microphone which is responsive to the sounds generated by the engine combustion occurrences. The microphone signal is passed through a band-pass filter having a variable center frequency which is determined by a control signal from a sweep generator. The control signal has a known relationship to the operating speed of the engine. As the band-pass filter is swept through its frequency spectrum, a peak detector identifies the signals of maximum amplitude, which occur at the fundamental frequency of the combustion occurrences. The control signal voltage at the maximum amplitude and hence at the fundamental frequency is stored. At the end of each sweep, the stored control signal voltage is fed to an oscillator having a frequency which is dependent upon the stored control signal voltage, and is related to revolutions per minute (RPM). The output of the oscillator excites a counter-display circuit which displays the operating speed in RPM.