Abstract: A trimmer head for string trimmer machines uses a fixed line segment inserted into a passageway in the trimmer head housing where the line is engaged by a trimmer line retaining tab secured in the main housing and extending into the passageway for engagement by a trimmer line segment inserted into an entry opening.

Abstract: A roll cage for a model car or truck is made of first and second elongated members and first and second inverted U-shaped cross members fabricated from flat metal stock. The roll cage is assembled by slip-fitting it together at mating slots formed into the elongated roll cage members and the inverted U-shaped roll cage members. A rigid roll cage is formed, which then is attached to the chassis of the model car or truck to overlie the components mounted on that chassis.

Abstract: Transcranial electrostimulation apparatus and method includes a first generator of bipolar pulses of a first predetermined frequency. A source of modulating control signals, producing an output at a second frequency less than the first predetermined frequency, is used to cause the output pulses from the first generator of pulses to vary in amplitude in a predetermined asymmetrical pattern at the frequency of the modulating control signals, with the asymmetrical pattern of signals applied to output electrodes designed to be attached to the scalp of a patient.

Abstract: A system and method are provided for obtaining mapping profiles of transparent objects having a plurality of reflective surfaces. The object, the surfaces of which are to be mapped, is placed in an unequal path interferometer including a reference surface located a predetermined distance from the object. Coherent light is supplied in the interferometer from a tunable source; and multiple optical interferograms for each of the plurality of reflective surfaces are simultaneously recorded. These interferograms are simultaneously extracted through the use of a dynamically generated weighted least-square fitting technique; which separates interferograms from a set of superimposed interferograms to obtain a given interferogram for any one of the surfaces, free from errors resulting from the existence of the other interferograms.

Abstract: A metal stud and clip assembly is designed for use in a non-load-bearing wall to allow a horizontal ceiling to vertically float thereon. This is accomplished by an elongated receiving channel on the stud spaced inwardly from its edges. A clip member has an elongated stabilizing bar slidably inserted into the channel, and the stabilizing bar itself then is secured to a horizontal ceiling or a track system mounted to the ceiling. Thus, relative movement of the ceiling with respect to the wall allows the stabilizing bar to move up and down in the receiving channel on the stud member.

Abstract: A digital audio transcription system includes at least one source of audio signals to be recorded and a computer for storing digital signals corresponding to the audio signals for allowing the stored digital signals to be subsequently played back. Recording sessions are defined by signaling the start and stopping of the digital signals; and the computer associates a date and time with each file segment stored during a recording session. A playback selection allows a user to select a virtual file entry from file entries corresponding to the periods of time during which the computer has stored at least one recording session, with the computer being responsive to the playback selection to identify file segments stored in memory on the desired entry date from the selected source of audio signals, which collectively represent the selected virtual file entry.

Abstract: A method and apparatus to linearize the phase shifts produced by the wavelength-varying driving mechanism of an interferometer used in phase shift interferometry for the measurement of multiple reflective surfaces first calibrates a sequence of physical values used as the input to the driving mechanism to produce a known linear or a known constant phase shift increment between any two adjacent interferograms. The calibration process, in essence, involves the determination of the sequence of physical values, such as the voltage change with respect to the time, through the process of iteration. This sequence then is used as an input to the phase shift driving mechanism for ongoing operation of the system, thereby compensating for non-linear characteristics of the system.

Abstract: The present invention consists of a technique and device for measuring the thickness variation and shape of wafers or other polished opaque plates. A combination of two improved phase-shifting Fizeau interferometers is used to simultaneously measure the single-sided distance maps between each side of the wafer and the corresponding reference flat, with the thickness variation and shape being calculated from these data. Provisions are made to determine and eliminate the shape and tilt of the reference surfaces, and also to facilitate the correct overlay of the two single-sided measurements for the calculation of thickness variation and shape.

Abstract: A device is disclosed for supporting semiconductor wafers or other polished, opaque plates for processing or metrology in a vertical orientation, where the wafer loading and unloading occurs in a horizontal orientation. The device consists of a pallet designed with an opening such that both sides of the wafer are exposed. The wafer is loaded into the pallet to rest on three fixed rest members extending a short distance into the opening. Moving clamp members on the frame are located for movement toward or away from the corresponding rest members. Two cylindrical rest pins are located on axes parallel to the central axis of the opening to permit the wafer to rest under the force of gravity on the rest pins when the frame is rotated to its vertical position. Special provisions are made to minimize the effects of mechanical vibration of the wafer while insuring a robust physical restraint of the wafer within the apparatus without inducing mechanical stresses which could influence the shape of the wafer.

Abstract: A system and method is disclosed for evaluating the likelihood of a person to subsequently develop a back injury on a job which requires some medium to heavy lifting and a variety of back movements. The system and method include measuring various back movements, namely flexion, extension, side bending, rotation and trunk flexibility, and then comparing each measurement against a pre-established threshold. Failing to meet the threshold in any one of the measurements disqualifies a person for the job under consideration.

Abstract: A thin, flat package of heat sealed thermoplastic material is filled with plastic string trimmer line by inserting a mandrel into an opening in the rear wall of the package to receive the free end of a length of string trimmer line inserted through a slot in the periphery of the package to engage the mandrel. The mandrel is rotated while the package is held in a relatively fixed position to wind line onto the mandrel and, therefore, into the package, until the package is filled. The mandrel then is withdrawn, leaving the free end of the line accessible through the opening in the rear wall, and the other end of the line extends from the slot in the periphery of the package.

Abstract: A combination backrest and storage compartment for a motorcycle or the like includes a bag made of flexible material, dimensioned to fit in the space between the driver's seat and the sissy bar of the motorcycle. A rigid frame is removably located within the bag, and the front of the frame is connected to the back of the frame by an elongated rigid brace. A flexible strap member is attached to the bag and extends around the front of the bag to allow it to be releasably secured to the sissy bar to pull the bag, and the frame located within the bag, rearwardly into tight engagement with the sissy bar. This secures the combination bag and storage compartment onto the motorcycle. A padded lumbar support backrest is attached to the outside of the bag adjacent the driver's seat.

Abstract: A napkin dispenser is designed with a flat base to rest on a horizontal surface. A substantially perpendicular flat front plate is mounted on the base, and a stack of napkins, resting on their edges on the base, is biased toward engagement with the front plate. The front plate carries a movable friction member, which may be in the form of a rotating device or a reciprocally mounted member, for engaging a napkin adjacent the front plate and moving it upwardly to remove it from the stack of napkins. The dispenser may be designed in kit form with different removable front plates, each carrying a different type of friction member.

Abstract: A Christmas tree lighting system for utilization with natural or artificial Christmas trees includes an outer elongated tubular covering having a zippered opening extending the length thereof. This outer cover may be either attached to the trunk of the tree, or suspended from an upper branch to extend along the trunk of the tree. The outer covering has attached to its interior one or more elongated flexible tubular casings, with a longitudinal zippered opening extending from the upper end thereof downwardly a predetermined distance toward the lower end thereof. The tubular casings in turn enclose a plurality of flexible optical fibers extending from the bottom thereof substantially toward the top of the casing. When the zippered casing is opened, the optical fibers may be bent outwardly therefrom and spread apart to lie along branches of a tree in which the lighting system is used. A source of light is applied to the bottom end of the optical fibers at the base of the tree.

Abstract: A machine and method for forming a spring coil in a length of hollow, cylindrical thermoplastic tubing comprises clamping the ends of a predetermined length of cylindrical thermoplastic tubing between first and second opposing spaced clamping members. In the machine, these clamping members include aligned first and second sections of a mandrel. These first and second clamping members then are rotated relative to one another by a predetermined amount selected to be slightly in excess of 360°, while the mandrels are simultaneously moved toward one another, to shorten the distance between the ends of the length of tubing, while the coil is formed. At the end of this relative rotation, the mandrel sections engage one another. The clamped tube, with the coil now formed around the mandrels, is rotated and simultaneously heated to the thermosetting temperature of the tubing. After a sufficient time to establish thermosetting of the coil, the heat is removed. Rotation continues while the tube is cooled.

Abstract: A cartridge containment device and method is designed to contain or catch unfired cartridges ejected from an automatic or semi-automatic firearm during unloading. To accomplish this, a cartridge containment box having an open top and otherwise configured with the general external configuration of a standard cartridge magazine is inserted into the firearm in place of the cartridge magazine. A blocking plate is attached to the cartridge containment box; and when the box is inserted into the firearm, the blocking plate is located adjacent the ejection port of the firearm, and prevents cartridges from being expelled therefrom. The cartridges then drop into the containment box for removal from the firearm.

Abstract: A shell of an animal restraint system is made from a radiolucent plastic material shaped to conform generally to the back, neck and head of the animal. The shell also has at least one region with a U-shape to permit the animal to be positioned on its back or on either side.

Abstract: Active power factor correction (PFC) circuits are used to minimize unwanted harmonic distortion in applications where AC electrical power is rectified to produce DC power needed for operating electrical equipment. A variable amplitude regulator (VAR) is a PFC control interface which is simpler to implement than conventional circuits, and offers a wider dynamic operating range. The VAR functions as a resistor scaling network using a two-stage RC filter to maintain the DC output voltage constant for various load conditions and to maintain the rectified current in phase with the sinusoidal circuit flow in an AC power line, through both slow and rapid changes in the load coupled to the direct current output. This control interface offers excellent performance characteristics and requires only a few components for a useful implementation.

Abstract: Pop-up cleaning heads of the type used in intermittently operated water delivery systems for cleaning pools and the like are provided with a decorative cover, removably attached to the upper surface of the pop-up cleaning head and extending beyond the edge of the cleaning head to overlie the top of the sleeve in which the cleaning head reciprocates. The decorative cover bears indicia and coloring on its upper surface selected to match the appearance of the pool floor surrounding the water delivery system.