Abstract: A pressure-sensitive switch comprising an electrically-insulating base member having front and back surfaces with a through opening extending between the two at the center of the base member. Two electrodes are mounted on the base member's front surface and each have an electrically-conductive contact surface. A flexible diaphragm has its periphery secured in a fluid-tight manner to the back surface of the base member and is provided with a post connected to the central portion of the diaphragm. The post extends through the base member where an electrically-conductive washer is fixed to it where it extends beyond the front surface of the base member. A fluid-tight cap is secured to the front surface, covering an area above the washer and preventing fluid from entering the switch mechanism. The diaphragm, which is formed with plural corrugations, is exposed to the external pressure.

Abstract: A method and apparatus for determining the geophysical position of an autonomous underwater system utilizing underwater acoustic modems that exchange broadband underwater acoustic signals. The method of the invention includes the steps of initiating an exchange of broadband acoustic signals between the autonomous system of unknown geophysical position and a base system of known geophysical position wherein the depths of both systems is known. A bearing calculation is made on one of the signals transmitted between the systems, preferably through the use of an array of hydrophones placed closely together at predetermined locations on either the autonomous or base system. Also, the range between the two systems is determined by measuring the time of travel of at least one signal.

Abstract: An underwater communications method and apparatus is provided for demodulating communications signals while compensating for the effects of range rate, i.e., relative velocity between the nodes of the communication system. The method of the invention is implemented in the DSP of an underwater bi-directional acoustic modem and method comprises the steps of generating a communication signal with an acquisition component for providing an initial estimate of the range rate. The acquisition component preferably is with a nonlinear frequency modulated acquisition component, preferably in the form of a hyperbolic frequency modulated signal, for providing the initial estimate of the range rate. Following this, a second set of signals, preferably a set of single frequency tonals, is generated and acquired using the initial estimate of range rate to obtain a more precise estimate of range rate.

Abstract: A data communications and underwater release management system for acquiring data from remote positively buoyant instrumentation packages moored underwater through the use of an intervening mechanical release coupled at one end to the buoyant instrumentation package and at the other to the mooring. A topside modem system provides bidirectional communication with an undersea modem commonly housed with the release to permit data generated from the instrumentation to be conveyed topside and/or send command signals to release the instrumentation package so that it can ascend to the surface for recovery, repair, or refitting. Power is supplied via an on-board battery whose energy level is monitored and directed when below a threshold value to operate only the mechanical release.

Abstract: Apparatus and methods for in-line testing of the internal pressure of flexible containers traveling along a production line at high speeds. The apparatus inspects semi-rigid plastic and thin-walled liquid filled containers by analyzing the output from a load cell that indirectly measures the reaction force applied to a container through the intermediary of a load cell roller that, in turn, supports a flexible belt that directly contacts containers while moving them through an inspection station without interrupting the flow of the production line. Containers are contacted only by a flexible portion of a conveyor belt to minimize structural and aesthetic damage to them that might otherwise occur during the inspection process.

Abstract: This invention relates to apparatus and methods for in-line testing for leaks in flexible containers traveling along a production line at high speeds. The apparatus inspects semi-rigid plastic containers at a high capacity by using multiple sensors at fixed displacements along a compression section while analyzing the response of the sensors such that internal pressure decays of leaky containers are readily discernible without interrupting the flow of the production line.

Abstract: The fluid tightness of containers having a first deformable section and a second deformable section spaced from the first deformable section is checked by changing the pressure applied to the first deformable section, preferably without causing fluid to flow through the first deformable section out of the container, and without changing the pressure applied to the second deformable section, thereby causing a deformation of the first deformable section and a change in pressure within the container; and thereafter monitoring a predetermined characteristic, preferably the position, of the second deformable section. This process can be used to check the fluid tightness of the containers with relatively fragile seals, for example, a foil lid of a food container without mechanical contact. Automated apparatus for carrying out this process is described.

Abstract: A pressure-sensitive switch comprises a base member having a mounting surface formed of electrically-insulating material; two electrodes mounted on the base member and each having an electrically-conductive contact surface, and a flexible diaphragm having its periphery secured in a fluid-tight manner to the mounting surface with its electrically-conductive central portion overlying the contact surfaces of the electrodes. The diaphragm, which is formed with plural corrugations, is exposed to the external pressure. When the switch is exposed to atmospheric pressure, the central portion of the diaphragm does not touch the contact surfaces of said electrodes, but when the switch is exposed to a super-atmospheric pressure, this central portion is forced into contact with both contact surfaces, thus electrically connecting the two electrodes. This pressure-sensitive switch is especially useful for use with hydrophones, as in seismic streamer cables.

Abstract: Method and apparatus by which misshapen crown caps on beverage containers, such as bottles traveling along high-speed bottling lines, may be detected. Bottles are arranged to travel directly beneath a magnetic proximity sensor head placed at a station along a conveyor. A photodetector indicates when a crown cap is properly positioned with respect to the magnetic proximity sensor. In the presence of a crown cap, the sensor head generates a signal having characteristic shapes indicative of properly shaped caps or those that are misshapen. The signal is monitored via algorithms for the presence of the characteristic shapes anticipated for properly shaped and misshapen crown caps and commands are generated in response to detecting reject crown caps.

Abstract: A method for analyzing the internal pressure of a closed container includes inducing vibration in a surface of the container; detecting sound resulting from the vibration; deriving information representing the detecting sound; and determining whether this information corresponds to a predetermined spectral frequency condition and a predetermined spectral amplitude condition. To ensure that the test results are not affected by modulating distortion which may be present in the information, the information is tested for the presence of a modulating distortion, and if so processed to compensate for the effects of this modulating distortion, prior to being tested against the predetermined spectral conditions.

Abstract: A transducer includes an elongated piezoelectric sensor having only a single integrated mass of piezoelectric material and a pair of relatively longer opposite edges and a pair of relatively narrower opposite edges. The transducer also includes a sensor support. The support imposes less constraint on one of the pairs of edges than on the other pair. Two piezoelectric sensors are supported back-to-back. Each of the sensors is held on opposite edges by a pair of opposite ledges, while two other opposite edges of the sensors are less constrained. The maximum displacement of the two less constrained edges of each sensor are limited by another pair of opposite ledges which are tapered or spaced away from the sensor when the sensor is in its normal position.

Abstract: A method of analyzing internal pressure of a closed container includes inducing vibration in a surface of a closed container; detecting sound resulting from the vibration; deriving information representing the detected sound; and determining whether the information corresponds to a predetermined spectral frequency condition and a predetermined spectral amplitude condition. The surface is at least partially conductive and inducing includes imposing a magnetic field on the surface. The predetermined spectral frequency condition and the predetermined spectral amplitude condition correspond to ranges of acceptable values. The detected sound is used to determine whether the closed container contains a pressure level within a predetermined range of pressure levels.

Abstract: A transducer includes an elongated piezoelectric sensor having only a single integrated mass of piezoelectric material and a pair of relatively longer opposite edges and a pair of relatively narrower opposite edges. The transducer also includes a sensor support that imposes less constraint on one of the pairs of edges than on the other pair.A transducer has two piezoelectric sensors, and a support for supporting the two sensors back-to-back. Each of the sensors being held on opposite edges by a pair of opposite ledges, while two other opposite edges of the sensors are less constrained. The maximum displacement of the two less constrained edges of each sensor are limited by another pair of opposite ledges which are spaced away from the sensor when the sensor is in its normal position.A transducer has two piezoelectric sensors mounted back-to-back on a housing that includes a rib which supports an edge of each sensor.

Abstract: Cable is stored a receptacle by a coiling mechanism. In the coiling mechanism, an arm receives the cable at an axis, and supports the cable as it passes from the axis to a feed end located at a point radially spaced from the axis. A cable driver forces the cable into the arm at the axis and toward the feed end. And an arm driver assists rotation of the arm about the axis while the cable is being forced into the arm at the axis.

Abstract: The internal pressure of a sealed container is characterized by tapping to vibrate a wall of the container, and then basing the characterization of the internal pressure on a frequency spectrum of the vibration and stored data measured from vibrating other sealed containers. The stored data is generated by vibrating a series of tests controllers having different, known internal pressures.

Abstract: Leak detector for use in detecting defective flange-shaped seals between lid and body portions of a package. A pressure chamber is provided for isolating the external edge of the seal and applying test pressure thereto. Containment of the pressure chamber includes sealing pressure applied mechanically to the flange-shaped package seal during testing, but this sealing pressure does not affect seal testing because it is appropriately limited by a self-compensating biasing of the mechanical seal. Also disclosed is a leak testing method that involves directing gas over a flexible lid at sufficiently high velocity to lift the lid at gross defects in a seal and inject gas through the gross defects. Also disclosed is a package design that employs channels to direct gas into a seal region.

Abstract: The leaky or non-leaky condition of a membrane-sealed container is determined by causing motion in one direction of one portion of the membrane; sensing motion in a direction opposite the first direction of another portion of the membrane; and delivering a corresponding signal indicative of the leaky or non-leaky condition.

Abstract: The leaky or non-leaky condition of a flexible, closed container is tested by increasing the pressure within the container (by causing motion of a wall of the container), and monitoring the resulting rate of change of a predetermined parameter (wall position or force exerted by the wall); the monitored rate of change indicates the leaky or non-leaky condition. In another aspect the time-varying net force on a container is the basis for determining the leaky or non-leaky condition.

Abstract: Leak detector for use in detecting defective flange-shaped seals between lid and body portions of a package. A pressure chamber is provided for isolating the external edge of the seal and applying test pressure thereto. Containment of the pressure chamber includes sealing pressure applied mechanically to the flange-shaped package seal during testing, but this sealing pressure does not affect seal testing because it is appropriately limited by a self-compensating biasing of the mechanical seal.