Abstract: A system and method for eliminating confusion associated with checking valves, wherein additional test points are added to the measurement of a valve for ensuring the verification of the actual sources of leaks or turbulence. A base line measurement for the valve is established by measuring the level of ultrasonic sound at the two points upstream from the valve. The level of the ultrasound at two downstream points is then measured. The value of the ultrasound at the downstream test points is compared to the values of the ultrasound at the upstream test points. If the values of ultrasound at the downstream test points are higher than the values of the ultrasound at the upstream test points, then the valve is leaking. If the values of the ultrasound at the downstream test points are close to or lower than the values of the ultrasound at the upstream test points, then the valve is not leaking, i.e., the valve is good.

Abstract: A method and apparatus for detecting leaks and mechanical faults by way of an ultrasonic device. An output from a variable gain amplifier is supplied to a pair of heterodyning circuits, i.e., a dual heterodyning circuit. At each respective heterodyning circuit, the output signal from the variable gain amplifier is multiplied by a local oscillator that is internal to each circuit. The dual heterodyning circuit is used to provide an enhanced input transducer signal for spectral analysis. This permits the capture of low level frequency components for extraction during spectral analysis. The dual heterodyning circuit of the present invention to provide the enhanced spectrum to thereby permit an easy determination of whether the resonance is mechanical or electrical becomes clear. In addition, fault frequencies are also more easily discernable. In other words, the enhanced signal output provides a lower signal to noise ratio such that the ease with which frequency components are analyzed is increased.

Abstract: An externally-powerable sensor is described for detecting ultrasonic energy and for providing an accurate indication of the level of such energy to an external monitoring device over a wide dynamic range. A first electrical signal proportional to the detected ultrasonic energy is chopped by the output of a free-running multivibrator to generate a signal having a frequency differing from the frequency of the first signal by an amount within the audio frequency range. Such difference signal is selectively amplified to concentrate the spectral energy of the difference component in a lower portion of the audio range. A low pass filter extracts, from the so-concentrated difference signal, a modified audio signal whose frequency content is at the lower end, illustratively 0-6 KHz, of the spectrum of the concentrated difference signal. The output of the low pass filter is processed to generate a DC output current that is proportional to the detected ultrasonic energy level.

Abstract: An externally-powerable sensor is described for detecting ultrasonic energy and for providing an accurate indication of the level of such energy to an external monitoring device over a wide dynamic range. A first electrical signal proportional to the detected ultrasonic energy is chopped by the output of a free-running multivibrator to generate a signal having a frequency differing from the frequency of the first signal by an amount within the audio frequency range. Such difference signal is selectively amplified to concentrate the spectral energy of the difference component in a lower portion of the audio range. A low pass filter extracts, from the so-concentrated difference signal, a modified audio signal whose frequency content is at the lower end, illustratively 0-6 KHz, of the spectrum of the concentrated difference signal. The output of the low pass filter is processed to generate a DC output current that is proportional to the detected ultrasonic energy level.

Abstract: The invention provides a device that generates predictable and reproducible sounds. The device according to the invention serves as a standard to calibrate ultrasonic measuring equipment through either a gaseous medium or a solid medium. The device according to the invention is similar in basic shape to an hourglass or venturi (e.g., a sand-type egg-timer), but instead of using fine particles, such as sand, the device includes identical media particles (e.g., marbles, balls, beads, etc.) which drop from an upper chamber to a lower one. The media particles are pre-sorted so that those sealed within the hourglass structure are uniform. An impingement post (e.g., a bell or sounding plate) is positioned in the path of the falling media particles so that each will hit the sounding plate, resulting in a reverberating sound. The impingement post is cantilevered and supported from a side of a chamber of the hour glass structure.

Abstract: The invention provides a device that generates predictable and reproducible sounds. The device according to the invention serves as a standard to calibrate ultrasonic measuring equipment through either a gaseous medium or a solid medium. The device according to the invention is similar in basic shape to an hourglass or venturi (e.g., a sand-type egg-timer), but instead of using fine particles, such as sand, the device includes identical media particles (e.g., marbles, balls, beads, etc.) which drop from an upper chamber to a lower one. The media particles are pre-sorted so that those sealed within the hourglass structure are uniform. An impingement post (e.g., a bell or sounding plate) is positioned in the path of the falling media particles so that each will hit the sounding plate, resulting in a reverberating sound. The impingement post is cantilevered and supported from a side of a chamber of the hour glass structure.

Abstract: An apparatus for detecting ultrasonic energy generated by a mechanical device and for applying lubricant to the device is presented. The apparatus includes a lubrication tool, such as a grease gun, which has a lubrication delivery element for delivering lubrication to the mechanical device. An ultrasonic transducer is contained in a housing which is removably attached to the outside of the lubrication delivery element. The housing is configured to acoustically isolate the transducer from the lubrication tool. An acoustic waveguide depending from the housing is provided to carry ultrasonic energy from the device to the transducer when the lubrication tool is applied to the device. An electrical circuit, which may be attached to the lubrication device, produces an output signal which indicates the magnitude of detected ultrasonic energy.

Abstract: The invention provides a device that generates predictable and reproducible sounds. The device according to the invention serves as a standard to calibrate ultrasonic measuring equipment through either a gaseous medium or a solid medium. The device according to the invention is similar in basic shape to an hourglass or venturi (e.g., a sand-type egg-timer), but instead of using fine particles, such as sand, the device includes identical media particles (e.g., marbles, balls, beads, etc.) which drop from an upper chamber to a lower one. The media particles are pre-sorted so that those sealed within the hourglass structure are uniform. An impingement post (e.g., a bell or sounding plate) is positioned in the path of the falling media particles so that each will hit the sounding plate, resulting in a reverberating sound. The impingement post is cantilevered and supported from a side of a chamber of the hour glass structure.

Abstract: An apparatus for detecting ultrasonic energy generated by a mechanical device and for applying lubricant to the device is presented. The apparatus includes a lubrication tool, such as a grease gun, which has a lubrication delivery element for delivering lubrication to the mechanical device. An ultrasonic transducer is contained in a housing which is removably attached to the outside of the lubrication delivery element such that the transducer makes acoustical contact with the lubrication tool. An electrical circuit, which may be attached to the lubrication device, produces an output signal which indicates the magnitude of detected ultrasonic energy. A method using such an ultrasonic energy detector in conjunction with a lubrication tool to detect the condition of a sealed mechanical rotating device and to determine when sufficient lubricant has been applied is also presented.

Abstract: An ultrasonic leak detector with a wide dynamic bandwidth and repeatable fixed attenuation reference points includes a transducer which receives ultrasonic energy and converts it into an electrical output signal related in intensity and frequency to the received ultrasonic energy. A high gain charge preamplifier is connected to the transducer and generates an amplified version of the transducer's electrical output signal. The amplified signal is then passed through a multi-level logarithmic attenuator having at least one fixed attenuation reference point to create an attenuated version of the detected and amplified ultrasonic signal. The output of the logarithmic attenuator is connected to a frequency shift circuit which converts the ultrasonic frequency signal into an audio frequency signal related in magnitude and frequency to the attenuated signal.

Abstract: Attached to a dobby for use in a loom is an actuator which is, in turn, attached to a first finger and a second finger to move them in unison in a cycle. The first and second fingers control the position of an upper hook and a lower hook. These hooks, when engaged by a knife, will raise a frame. During the first half of a cycle, the actuator positions both fingers in either an upper or lower position. In the second half of the cycle, the actuator positions the fingers in either the upper or lower position.

Abstract: Ultrasonic vibrations indicating trouble at remote locations are detected by sensors spaced in the vinicity of expected trouble. These sensors have weather resistant transducers that convert ultrasonic vibrations from a leak in a conduit, electrical arc, bearing vibration or the like, into an electrical signal. In the sensor there are circuits that amplify the electrical signal and transmit it with a current loop transmission system over a twisted pair of wires to a central control and analysis computer. The amplification of the signal at the sensor is controlled by a signal from the center computer which changes the gain increments until the sensor circuits are not saturated by the ultrasonic signal. This gain control signal is also delivered to the sensors over a twisted pair of wires by current loop transmission system.

Abstract: Leaks or thin spots in containers, as well as mechanical faults, e.g. worn bearings, are detected by an ultrasonic energy indicator that includes a modulator that heterodynes ultrasonic signals received by a transducer and creates an audio signal related thereto. The transducer includes a series arrangement of piezoelectric crystals feeding a field-effect transistor amplifier and the modulator operates in an amplitude modulation, suppressed-carrier mode which can be stabilized by a feedback loop. For indicating the presence of the audio signal, either headphones or a meter or both are employed. When leaks in a container are being detected, an ultrasonic generator is used which varies its output frequency slowly over a band of frequencies. The leak detection technique can be improved by applying a thin layer of a liquid to the container surface so that pressure introduced into the container causes the formation and bursting of bubbles in the liquid that results in the production of ultrasonic energy.

Abstract: Leaks or thin spots in containers, as well as mechanical faults, e.g. worn bearings, are detected by an ultrasonic energy indicator that includes a modulator that heterodynes ultrasonic signals received by a transducer and creates an audio signal related thereto. The transducer includes a series arrangement of piezoelectric crystals feeding a field-effect transistor amplifier and the modulator operates in an amplitude modulation, suppressed-carrier mode which can be stabilized by a feedback loop. For indicating the presence of the audio signal, either headphones or a meter or both are employed. When leaks in a container are being detected, an ultrasonic generator is used which varies its output frequency slowly over a band of frequencies. The leak detection technique can be improved by applying a thin layer of a liquid to the container surface so that pressure introduced into the container causes the formation and bursting of bubbles in the liquid that results in the production of ultrasonic energy.