Abstract: Displacement measuring apparatus comprises a light source (10), a lens (12), and index grating (14), a reflective scale grating (16), and three photodetectors (18) at positions corresponding to the zero order and positive and negative first order images of the source (10). The index grating (14) has a castellated surface profile with a mark/space ratio (a/b, FIG. 3) and a castellation height (h, FIG. 3) chosen so that the three photodetectors (18) see wavefronts having a phase separation of 120. The electrical signals from the photodetectors (18) are used to sense the magnitude and direction of movement of a reading head carrying the components (10, 12, 14 and 18) with respect to the scale grating (16).
Abstract: An encased position measuring instrument for measuring the relative position of two objects comprises a housing, a measuring scale and a scanning unit. The measuring scale is scanned by the scanning unit which is connected to a fastening member by means of a connecting rod. The connecting rod moves through a frontal opening in the housing which is hermetically sealed by a sealing unit. To avoid undesirable constraining forces exerted on the connecting rod when the housing changes position, the sealing unit is fastened to the housing by means of rods or wires. These rods run parallel to the connecting rod and are rigid in the measuring direction but allow movement of the sealing unit at right angles to the measuring direction.
Abstract: In a length measuring apparatus for measuring the relative position of two objects movable relative to each other a scanning unit fastened to the first object scans the graduation of a scale fastened to the second object. The scale is connected to the second object at both ends by means of two fastening elements. Each fastening element has a length compensation element allowing translatory movement of bearings at the ends of the scale in the measuring direction. The fixing of a reference point on the scale with respect to the second object is accomplished by means of a fixing element which renders one of the length compensation elements ineffective in its functioning.
Abstract: A carbon-in-ash monitor uses a fluidized bed furnace to burn any carbon in sampled boiler flue ash and evolve carbon dioxide therefrom. Fluidizing gas (air) is provided to the bed a measured flow rate and a batching arrangement feeds successive batches of ash of measured mass to the furnace at a measured frequency. A CO.sub.2 monitor measures the amount of CO.sub.2 evolved to determine the carbon content of the ash. Batches are provided using a vibratory table to transport ash from a point of supply to the table and a point of delivery of ash in a stream from the table. The vibratory table is horizontal and is driven so that the mode of vibration can be selected to reverse the direction of ash transport.
Abstract: A system for removing trapped air layers is disclosed for use in a measuring apparatus such as a length measuring apparatus for measuring dimensions of a test object supported on a measuring surface. According to this invention, the measuring surface defines in the region beneath the resting surface of the test object a plurality of openings which are connected to a source of subatmospheric pressure in order to draw off any trapped air layer present between the measuring surface and the resting surface of the test object. In the illustrated embodiment, these openings are connected with an external suction line by means of channels defined in the measuring table.
Abstract: A sturdy and reliable mount for a double-paned glass unit that is readily used with standard glass units and frames, that is easily installed, that eliminates the need for endcaps or exterior stops, and that uses a flexible connector member as part of the mount is disclosed. The application of such a securement as a secondary mount to back-up a primary mount for a double-paned glass unit, such as a structural silicone adherent, is a particularly advantageous use of the invention. An embodiment includes a resilient, or flexible, elastomeric member having a first portion received in a channel formed between the glass plates of a double-paned glass unit and a second portion extending beyond the perimeter of the glass unit. The second portion of the resilient member is fixed to the structure on which the glass unit is to be mounted, such as a building. The invention can also be used with a double-paned glass unit having an inset exterior glass plate.
Abstract: The compounds of the present invention are linear and branched dextrans having a plurality of their glucose units modified at the 3-position ring carbon with groups selected from the class consisting of keto, amino, halo, benzyl, alkyl, sulfonyl, carboxyl and hydrogen. The modified dextrans reduce and/or modify activity of glucosyltransferase enzymes (GTF) which are produced by oral strains of Streptococcus mutans bacteria. GTF enzymes mediate oral biosynthesis of plaque-forming glucose polymers (glucans) from ingested sucrose. Therefore, the dextrans of the present invention, which reduce and/or modify activity of GTF enzymes, are useful in reducing the formation of dental plaque. The present invention is further directed to a dental health method comprising the step of contacting the oral cavity with linear or branched dextran compounds having a plurality of their glucose units modified at the 3-position carbon with a group such as keto, amino, halo, benzyl, alkyl, sulfonyl, carboxyl or hydrogen.
December 16, 1986
Date of Patent:
August 30, 1988
Wm. Wrigley Jr. Company
Ioannis S. Scarpa, Andrew M. Chludzinski, Milan D. Janic
Abstract: A reflective optical wheel speed transducer system is disclosed. The system utilizes a single optical fiber to transmit light to a pair of interrupter discs, and to collect light reflected from the discs. One of the interrupter discs is stationary, and one is rotated at an angular velocity proportional to the rotational speed of a wheel. Both discs are provided with alternating, regularly spaced reflecting and transmissible areas. The reflecting areas of the stationary disc reflect a constant bias level of light to the optical fiber. The reflecting areas of the rotatable disc modulate light passing through the transmissible areas of the stationary disc at a rate proportional to the angular velocity of the wheel. Thus, the interrupter discs generate a modulated light signal that rides on top of the fixed bias signal. Decoding circuitry is provided to convert the modulated component of the light signal to an electrical signal that represents the rotational speed of the wheel.
Abstract: There is disclosed a portable trap holder for use with a body type animal trap. This type of trap generally has a spring arm which biases a pair of hinged trap jaws toward a closed position, a trigger for releasably holding the trap jaws in an open position, and means for anchoring the trap. The portable holder of the invention includes a box with a bottom, top, two opposing sides, and at least one open end. The open end is of sufficient dimensions to receive the trap jaws while in the open position. A notch is included in one of the two opposing sides, adjacent to the open end, and about midway between the top and bottom. This notch is adapted to receive the spring arm of the body type animal trap. When the spring arm is received into the notch, the trap jaws, while in the open position, lie in a plane generally parallel to the plane of the open end of the box, and, while in the closed position, lie in a plane generally perpendicular to the plane of the open end of the box.
Abstract: Multiple layer nonoriented heat sealable films are disclosed having a base substrate layer of poly(ethylene terephthalate) (polyester) or polyester copolymer and at least one heat sealable surface layer of a copolyester. The films are prepared by conventional cast or blown film coextrusion techniques.
Abstract: A position measuring instrument, comprising a scanning grid, a scale grid and an illumination unit, is used to produce two sets of diffracted partial light rays. The scanning grid defines a grid constant and is formed by two scanning fields, constructed as phase grids, offset to one another in the measuring direction by 1/4 of the grid constant. The phase grids have a slat-to-furrow width ratio that deviates from a 1:1 ratio. The scale grid has the same grid constant as the scanning grid but has a slat-to-furrow ratio of 1:1. The grids cooperate with the illumination unit to produce diffracted partial light rays of several orders. An oppositely deflecting prism is allocated to each scanning field. A first and second set of diffracted partial light rays are generated, wherein the second set is opposite in phase to the first set. A photodetector is allocated to each respective selected order of the two sets of light rays to produce corresponding electrical signals.
Abstract: A protective device includes a transmission line comprising two elongate co-extensive electrical conductors capable of sensing vibrations, converting these vibrations into electrical signals and transmitting the electrical signals. It also includes signal-processing means electrically connected to one pair of ends of the conductors. The signal-processing means includes normalizing means for normalizing the electrical signals, and a comparator for comparing the normalized signals with previously normalized known signals, thereby to identify the source of the signals transmitted along the cable, and hence an alarm/non-alarm condition.
September 16, 1986
Date of Patent:
August 16, 1988
Sekerheid en Elektronika Laboratoria (Eiendoms) Beperk
Abstract: A drive system for a down hole oil well pump includes a cylinder assembly which defines first and second cylinders. A pump rod which includes first and second pistons, each disposed in a respective one of the cylinders, is coupled to the down hole pump. A hydraulic accumulator supplies a resilient biasing force to one of these pistons to counter the weight of the ram interconnecting the pump rod and the down hole pump. A hydraulic pump supplies pressurized hydraulic fluid which is alternately directed against upwardly facing and downwardly facing piston faces of the pump rod to cause the pump rod to oscillate, thereby driving the down hole pump. Fluid level sensors deactivate the hydraulic pump when the oil level in the oil well falls below a pre-set level.
Abstract: A servo valve assembly having torque feedback includes a housing and a valve spool disposed for axial translation therein. The valve spool has a plurality of lands alternating with three reduced diameter regions which cooperate with axially spaced apart inlet, return and service ports in the housing. The servo mechanism includes a piston integrally formed with the valve spool. An axial bore extends through the spool and receives a control rod having an axially extending flat which cooperates with radial passageways in the valve spool. At the end of the control rod is a torque motor which rotates bi-directionally and provides an input signal to which the servo valve assembly responds. Between the torque motor and the valve housing is a torque feedback assembly. The assembly includes a pair of cantilever spring arms each fixed at one end, the opposite ends of each of the cantilever arms coupled to a respective pair of pistons which are in communication with respective service ports.
Abstract: An internal wrench for an earth drilling machine of the type having a mast, a top head drive assembly mounted for movement along the mast and a quill rotated by the top head drive assembly includes a body having an upper end and a lower end sized to fit within a length of casing. The upper end of the body is mounted to the quill for rotation with the quill and several jaws are mounted to the lower end of the body to move between an extended position in which the jaws engage in interior surface of the casing to rotate the casing with the body, and a retracted position in which the jaws are out of engagement with the interior surface. The jaws are selectively moved between the extended and retracted positions in response to rotation of the body by a system which includes a drag ring which operates the jaws and a friction brake which engages the drag ring. A plug is mounted to an intermediate portion of the body to mate with threads at the upper end of the casing to seal off the casing.
Abstract: A process and apparatus for improving the resolution of square, subdivided signals by synchronizing the signals with an auxiliary clock signal. The signals are further conditioned by switching logic elements which, in dependence upon adjacent signals in the subdivision order and upon the auxiliary clock signal, only allow the states of the signals to change at predefined times.
June 18, 1986
Date of Patent:
July 26, 1988
Dr. Johannes Heidenhain GmbH
Ernst Schwefel, Martin Huber, Alois Zimmermann