Abstract: An acoustic sensing system to measure an interior characteristic of an object, for example, density, the presence of defects, or bond integrity (of a laminated object). The system includes a first set of acoustic transducers acting as transmitters for transmitting acoustic wave energy at a single frequency, which acoustic wave energy interacts with the object in a sensing region to provide transmitted, scattered, and reflected wave energy. A transmitter mounting mechanism allows the transmitters to be positioned in such a way that acoustic energy reflected from the object sets up a reverberation between the transmitter and the object. A second set of acoustic transducers acting as receivers of acoustic wave energy is positioned opposite the transmitters in such a way that acoustic waves passing through the object are coupled to the receivers.

Abstract: An acoustic sensing system to measure an interior characteristic of an object, for example, density, the presence of defects, or bond integrity (of a laminated object). The system includes a first set of acoustic transducers acting as transmitters for transmitting acoustic wave energy at a single frequency, which acoustic wave energy interacts with the object in a sensing region to provide transmitted, scattered, and reflected wave energy. A transmitter mounting mechanism allows the transmitters to be positioned in such a way that acoustic energy reflected from the object sets up a reverberation between the transmitter and the object. A second set of acoustic transducers acting as receivers of acoustic wave energy is positioned opposite the transmitters in such a way that acoustic waves passing through the object are coupled to the receivers.

Abstract: A scanning system for monitoring the thickness, profile or other data from a moving product which includes a frame for mounting scanning transducers. The product is carried on a conveyor or the like through the frame and the transducers are mounted for transverse scanning motion across the top and bottom surfaces of the product at right angles to its direction of travel. Reference wires are connected between the side members of the frame and maintained at a constant tension independent of ambient temperatures. Reference wires are located between the transducers and both the top and bottom surfaces of the product. The wires provide a constant reference to detect distortion of the frame due to thermal or other stress and to provide correction data which is used to compensate for frame irregularities.

Abstract: A capacitive transducer including a back plate and a tensioned dielectric diaphragm with a conductive layer is operated as a sonic energy emitter and receiver. The polarity of the dc bias applied to the transducer is periodically reversed to prevent charging and polarization of the dielectric diaphragm due to the applied electrostatic field. The bias voltage polarity is controlled in timed sequence with the application of a fluctuating voltage to generate sonic energy with optimum efficiency. Electrical signals resulting from received sonic energy are selectively inverted and provided with compensation for differences resulting from differences in bias polarities.

Abstract: A self-contained theft and vandalism deterrent system for equipment security includes sensors (12) for detecting conditions to which an alarm (24, 26, 28, 50) is responsive. The analog signals from the sensors (12) are serially delivered by a multiplexer circuit (16) when they are then directed to a network (20) for conversion to digital signals. The digital signals are delivered to a micro processor (22) where the signals are evaluated to determine if an alarm condition exists. The sensing means (12) include sound and vibration detectors for monitoring the ambient envelope. The micro processor (22) includes built in reprogramming and comparator circuits for varying the level at which a given condition will trigger an alarm response.

Abstract: A control system for a shiftable multi-speed hydraulically operated transmission system. The transmission includes internal clutches which are selectively operated by the control system to effect shifting in neutral, reverse or forward speed ranges. The transmission system includes a manually operable multi-position speed range selector switch, sensing devices for ascertaining transmission input and output speeds, and other condition responsive switches. The control system includes logic circuits therein for receiving input signal information from the switches and sensing devices and for providing output signals to effect automatic shifting of the transmission to a selected speed range. The electronic controller provides operational safeguards, responds appropriately to system failures, and displays of relevant system information.