Abstract:
A variable-frequency feeder control using a single oscillator to develop signals for moving materials in either one of two directions. An output signal from the oscillator is applied to a first timing circuit which develops signal pulses for driving a horizontal electromagnetic drive coil. The first timing circuit controls the duration of the signal pulses which determine the amplitude of power to drive the horizontal coil. The output signal from the oscillator is applied to a second timing circuit which developes a phase shifted signal to control the phase between the power applied to the horizontal coil and the power applied to a vertical drive coil. A third timing circuit uses the phase shifted signal to develop signal pulses for driving the vertical coil and controls the duration of the drive pulses.
Abstract:
A vibratory amplitude controller for vibratory mechanisms such as a vibratory feeder having in addition to a parts container, an electromagnetic drive unit operated from an A.C. current source for imparting oscillatory motion to the parts container. The controller includes a sensing means for sampling the electromagnetic drive unit current during a specific predetermined interval each A.C. current cycle to produce a vibratory amplitude representing signal. Means responsive to the vibratory amplitude representing signal controls the amount of power delivered from the A.C. current source to the electromagnetic dive unit to maintain a desired vibratory amplitude under varying load and A.C. line voltage conditions.
Abstract:
A control system is disclosed for use with a device, such as a vibratory bowl feeder, having a bowl or other member mounted for vibratory motion and including an electromagnetic driver for vibratorily driving the part. The control system includes a detector for detecting the vibratory frequency of the part, which tends to vibrate at its resonant frequency, and causes energizing pulses of power to be supplied to the driver supplied at a frequency equal to the detected frequency. Thus, the driving frequency is made equal to the resonant frequency and follows changes in such frequency to obtain maximum performance. The power to the drivers is also switched so that during alternate pulses the current flows through the driver coil in opposite directions to inhibit buildup of residual magnetism in the coil core. The control system uses a phase-locked loop circuit and other parts comprised of components most of which are available as standard integrated circuits. A means for selectively varying the amplitude of member vibration is also included in the control system.
Abstract:
A method of draining parts emerging from hot galvanizing baths using a range of vibration excitation frequencies capable of covering the fundamental frequencies of the parts to be drained. Three different methods are disclosed. According to a first method the vibrations are obtaining by exciting with a narrow band white noise the support for the parts to be drained. According to a second method, the vibrations are produced from a single exciter fed with narrow band white noise and energizing vibrators through the medium of amplifiers. According to a third method, the vibrations are produced by a number of small vibrators each of which furnishes one of the frequencies of the chosen spectrum, whereby said vibrators jointly synthesize the narrow band white noise. Three different means are disclosed for producing vibrations, one where the vibrators are mounted on a false lifting beam, the second where the vibrators are mounted on the lifting beam, and the third where the vibrators are enclosed in a container placed between the lifting beam and the hoisting means.
Abstract:
A system for inspection of adhesively bonded structures utilizing a piezoelectric transmitting transducer for transmitting a fixed frequency tone burst, e.g., 25 KHz, at a predetermined repetition rate, e.g., 100 Hz, into a part being tested and including a piezoelectric receiving transducer also coupled to the part for providing in a receiver circuit an audible output which permits the operator to distinguish amplitude variations of the 100 Hz repetition rate signal representative of the presence of an unbonded area.
Abstract:
A wide bandwidth, high gain ultrasonic frequency transducer drive circuit utilizes a relatively low voltage source of supply voltage. A first signal path from a source of drive signals includes circuitry resonant with the transducer for providing a relatively high signal voltage across this transducer. A second signal path from the source of drive signals includes a resonant circuit mutually coupled to the first resonant circuit for inducing signal energy into the first path and increasing the signal voltage across the transducer.
Abstract:
An illustrative embodiment of the present invention includes acoustic transmitting transducer apparatus for use in well borehole logging which provides a sharper, more intense pulse of acoustic energy than heretofore possible while at the same time eliminating undesirable electric fields in the vicinity of the transducer element. Novel circuit means including remote mounted charge storage means, switching means, voltage transforming means and isolation circuitry together with mechanical end clamping are combined to produce this result.
Abstract:
A cooling system including a heat load; a supply line supplying a cold coolant to the heat load, wherein the cold coolant receives heat from the heat load and becomes a hot coolant, a return line receiving the hot coolant from the heat load, a transducer generating elliptical ultrasonic waves, and a horn coupled to the receiving line and receiving the hot coolant, wherein the horn conveys the elliptical ultrasonic waves to the hot coolant. The hot coolant, in response to the horn conveying the elliptical ultrasonic waves, undergoes heat loss through convection. Elliptical ultrasonic waves are provided by a transducer combining a longitudinal actuator and a bending actuator.
Abstract:
Described herein are apparatuses and methods for use therewith that can be used to remove dust and other types of particulates from a solar array of a spacecraft, a lander, a rover, or the like. Such an apparatus can include a main body and a solar array extending from the main body. One or more piezoelectric devices is/are attached to the solar array. The piezoelectric device(s), when activated, is/are configured to vibrate at least a portion of the solar array to thereby loosen particulates adhered thereto. The apparatus also includes one or more linear actuators that when actuated is/are configured to at least one of bump against, push on, or pull on at least a portion of the solar array to thereby jettison from the solar array at least some of the particulates that were loosened by the one or more piezoelectric devices.