Abstract: The apparatus comprises a stable carrier plate for carrying prisms cemented thereto and conducting an optical ray path from its source to a position sensitive photoelectric receiver. A liquid horizon is provided on the carrier plate for shifting the optical ray path if the apparatus is inclined. A design stable against temperature and mechanical stress with a flat and compact shape is achieved in an easily mountable two axes inclinometer.

Abstract: A trailer measuring system (10') for leveling a trailer during setup and for indicating deviations from an initial position of level of a trailer is provided. The device (10') includes a reservoir (16') and a plurality of measuring tubes (18') which can be secured to the frame (12) of a trailer (14) at horizontally spaced locations. Fluid communication is provided between the measuring tubes (18') proximate their lower end portions by tubing (20') and between their upper end portions by tubing (22) which connects the measuring tubes (18') in series or series/parallel to form a closed system. Fluid communication is selectively provided between the upper and lower end portions of the measuring tubes (18') and the upper and lower portions of the reservoir (16'), respectively.

Abstract: A sensor controlled leveling device comprises an attitude detector and/or a laser sensor. In order to create a sensor controlled leveling device with which a desired relative attitude may be automatically set and held the attitude detector has a float which is supported and pivoted in a central part. The laser sensor comprises a zero point recognition means whose output is connected with electronic processing circuitry for at least one servo drive. Using the control unit it is possible for the drive to be operated in a direction opposing a relative change in setting of the laser sensor in relation to a reference plane as swept out by a laser generator so as to correct deviation of the laser sensor from the reference plane.

Abstract: A post-avalanche upward indicating aid device is provided. The device includes a body, an illumination source and an attachment means. The body has a generally central cavity which is partially filled with a liquid and closed or sealed. The illumination source enables the liquid in the cavity to be observed in darkness and an attachment point is provided so that the device can be securely fastened to or carried by a user.The aid device incorporates the effect of gravity on a liquid contained in a closed, partially liquid-filled cavity. That is, gravity draws the liquid in the partially liquid-filled cavity in a downward direction so that the partially-empty area or bubble in the cavity will always tend toward a position above the liquid. Thus, by observing the location of the bubble in the central cavity, the device provides an automatic, immediate and readily visible indication of the generally upward direction to a victim buried in snow after being caught in an avalanche.

Abstract: An inclinometer 20 has a sensing unit 40 for providing a varying capacitance signal depending on the orientation of the inclinometer 20. An oscillator circuit unit 82 includes the sensor unit 40 as a capacitive element for providing a signal having a period and a frequency depending on the capacitance of the sensor unit 40. A unit 92 is provided for determining the period of the signal. A look-up table unit 96 stores a predetermined relationship between the period of the signal and the angle of orientation of the inclinometer 20. A comparison unit 94 then compares the period of the signal to the period stored in the look-up table unit 96 and selects the corresponding angle which is the angle of orientation of the inclinometer 20. The angle is then displayed on the inclinometer display 25.

Abstract: An orientation indicator is disclosed for observing or reading the orientation of the distal end of an endoscope or of a fiberscope having an elongated flexible shaft relative to the proximate end thereof where the flexible shaft the fiber optic bundles of the scope are subject to torque or rotational stresses. The disclosure includes a method of making the orientation indicator and means for measuring the degree and direction of displacement resulting from said rotational stress or torque.

Abstract: An inclinometer is characterized wherein a thin, transparent plastic cylindrical container filled precisely one-half its volume by an inert liquid, is located in the middle of a homogeneous base in the shape of a quarter-circle whose two straight edges are exactly perpendicular, and when positioned upright, the surface of the liquid forms a longitudinal line intersecting the center of the cylinder and the first degree scale marked on the bottom of the cylinder; such that by viewing the said first scale opposite the liquid level, one can rapidly and directly measure the angle displaced by an object over a full 360-degree movement; or, for the purpose of finding any deviation from the horizontal plane, in any and all of the North, South, East and West directions, and/or any direction in-between each direction, can be measured by laying the inclinometer flat on the surface of the object whose inclination is to be measured, and the angular displacement is read directly from the second scale imprinted on the exter

Abstract: A bow mountable range finder for elevated tree stand use includes a housing and a triangular tubular chamber containing air and medium viscosity liquid. The triangular chamber contains a horizontal venting section, a vertical indicating section, an inclined section and a horizontal reservoir with air and liquid freely movable throughout chamber depending upon the orientation of the range finder. The indicating section is translucent and has a removable graduated scale calibrated for various heights above ground, a battery powered lamp illuminates through the indicating section and scale. A switch is operable by an archer outwardly of the housing.The reservoir section is sized to accommodate approximately one-half the fluid capacity of the indicating section when the range finder is horizontal and thus allows for rapid lowering of the liquid level when the range finder is rotated counterclockwise.

Abstract: The ring-shaped sighting device comprises an annular ring-shaped space the axial height of which decreasing from a window provided in the annular space for observing the level of the liquid to the opposite side. Hence, the uneven bottom forms a displacer for the liquid present in the annular space, so that the volume of this liquid versus its surface can be maintained of a low value on the entire periphery of the annular space. In this way, thermal dilatation of the liquid has no significant importance on the level of the liquid which guarantees an indication largely independent of the temperature.

Abstract: A level indicating device used to indicate proper orientation of a recreation vehicle (RV) such as a motor home, trailer, or camper. The device comprises of a generally transparent dome fixedly mounted on a base which can be removeably attached to a generally flat, horizontal surface which is preferably the ceiling of the RV. The dome is approximately half-filled with a liquid which is resistant to freezing, and carries a plurality of parallel lines graduated to indicate when the orientation of the base with respect to horizontal is within a three degree tolerance. In operation, the surface of the liquid lies generally between the plurality of parallel lines when the flat surface to which the base is attached is within three degrees of tolerance with respect to horizontal. The dome is illuminated by a conventional pen light removeably inserted into apertures in the base, the light being activated by pressing on one end of the light.

Abstract: An acceleration or inclination sensor includes at least two condensers formed as a reference electrode and a detection electrode divided into at least two portions. A magnetic fluid is provided between the reference and detection electrodes, and a magnet or electromagnet is provided for generating magnetism acting upon the magnetic fluid around the location at which the detection electrode is divided, whereby acceleration or inclination is detected by a change in the capacitance of the condensers in terms of an electrical signal.

Abstract: An inclination measuring apparatus having a prism and a container having a liquid sealed therein for providing a liquid surface perpendicular to the direction of gravity. A member constructed from thermal conductive material is position under the liquid surface to maintain the liquid surface level in the presence of ambient temperature changes.

Abstract: The instrument includes a cylindrical chamber with two parallel end walls. At least one of the end walls is plated with two semicircular condenser plates forming a gap between them. The chamber is filled half and half with two non-intermixing liquids of different specific gravity. In one embodiment the other end wall is plated with a third condenser plate and the two liquids are non-conductive and have different dielectric properties. In another embodiment, the two condenser plates on the one end wall are plated with a dielectric layer and at least one of the two liquids is an electrolyte. The instrument has a high measuring range and high accuracy and resolution.

Abstract: The inside surface of a conductive vessel (preferably spherical) with insulated adjacent segments is coated with a dielectric layer. The vessel is then partly filled with a conductive liquid-like material such as mercury having an upper surface which remains approximately horizontal irrespective of the inclination of the vessel. The capacitance between the segments and liquid varies as a function of the vessel's inclination. Vibration-induced surface action also produces varying capacitance which can be detected for seismometer applications and the like.

Abstract: An electronic level includes a conductive gravity-levelled reference element (33) and one or more pairs of sensing electrode members (A1-D1) supported in spaced confronting relation to the reference element on a flat rigid support (37) which is movable relative to the reference element. A dielectric fluid separates the reference element (2) from the sensing electrode members so that at least one pair of capacitors is formed the capacitances of which capacitors vary oppositely in response to deviation from level position of a line joining the pair of sensing electrode members and the consequent loss of parallelism of that line with the reference element. Alternating voltages are applied to the capacitors such that the product of the capacitance and the applied voltage is equal for both capacitors when parallelism exists. A detecting means senses variations of the capacitances and provides an indication of any deviation from level position of the flat support (37).

Abstract: The present device comprises a tubular sleeve (1) which is opaque and which surrounds a part of the length of a tube (2), and provided with an observation window (3) permitting the appearance of the level (4) of a liquid contained in a first tubular compartment (5) forming part of a system of communicating vessels. An annular chamber (10) communicates with the compartment (5), particularly by way of a second compartment (12) and a connecting conduit (11). The ratio between the section of the annular chamber (10) and that of the tubular compartment (5) is such that the variation in the liquid level is very strong in this compartment as compared with that in the annular chamber.The invention is particularly applicable to a sighting device for a mortar.

Abstract: Apparatus for monitoring the percent of grade and controlling machinery in response thereto is disclosed. A novel grade sensor A includes a reservoir 14 filled with a translucent fluid medium 30 to a predetermined level L. Grade sensor A is adapted for attachment to associated machinery such as casing head 50 of casing pipe 40 being simultaneously bored and pushed underground. A light emitting diode 18 transmits light through the fluid containing reservoir. Light detector 16 is located opposite the diode for detecting light intensity and has an output representing the intensity. Light intensity changes due to changes in the orientation of the sensor and inclination of the surface level of the fluid medium is used to indicate changes in percent of grade. Electrical means F converts output of detector 16 into a visual display of percent of grade change.

Abstract: A level indicating device comprises a compressible container, which is charged with a measuring liquid, and a flexible transparent tube having a first end immersed in the liquid within the container. The second end of the tube may be affixed to a support which has a reference level marking means mounted thereon. When the device is in use, the surfaces of the fluid in the container and in the second end of the tube are exposed to the ambient atmosphere whereby, when in equilibrium, both surfaces will be at the same level.

Abstract: A sighting device for enhancing a golfer's putting accuracy comprises an elongated vertical sight and a liquid level, which are provided by a compact hand-held, semitransparent or translucent casing with particular indicia and contained liquid. After the golfer moves to a position at which he views the ball and the cup along their shortest interjacent path, he views the position of the cup with respect to the ball in reference to the sight and plumbs the sight in reference to the level. A correct indication of how the ball will break thereby is provided.

Abstract: The invention relates to an aiming instrument for a small arms weapon comprising an arrangement for directional aiming and an arrangement for vertical aiming, wherein the directional and vertical arrangements are integral and a fixing device is provided to connect them detachably to the barrel of the weapon; the directional aiming arrangement includes an alidade; and the vertical aiming arrangement comprises at least one partially transparent chamber containing at least one movable mass which is displaced opposite a scale.

Abstract: The corrected values to compensate for errors in instrumental levelling of a theodolite and similar instruments are found by determining angles of elevation and/or horizontal directions, measuring the instrumental levelling errors, and calculating the error free values of the instrument.

Abstract: An alignment device comprising a plurality of hollow arcuate sections secured together at their inner edges so as to form a hollow center with a base support member, an aperture for admitting fluid and scalar indicia about the outer edges of the arcuate section. The device may be adapted to removably accept a rigid rod opposite said base, said rod being adapted for insertion into the chuck of a drill.

Abstract: A miniature automatically self-aligning azimuth reference employs a floated pendulous gyrocompass device for the rapid determination of geographic north as required for surveying purposes. Fast alignment with north from an initially misaligned condition is effected in an iterative manner through the action of a unitary vertical-axis magnetic centering-torquer-pick off system employing eddy current forces.

Abstract: Apparatus for measuring the vertical displacement between a remote point and a reference point. The apparatus comprises a pair of reservoirs, each having a liquid working fluid disposed therein, a differential pressure transducer and a hydraulic coupling means for each of the reservoirs. Each hydraulic coupling means couples a point in the reservoir below the top surface of the working fluid to an associated input port of the pressure transducer. A vapor pressure equalization means is provided for the reservoirs whereby the points above the top surface of the working fluid in each reservoir are maintained at substantially equal pressures. The apparatus further includes a volumetric temperature compensation means for offsetting temperature dependent changes in the volume of the working fluids which occur in the hydraulic coupling means.

Abstract: The specification discloses a magnetic liquid core toroidal transformer having four secondary windings spaced 90.degree. apart. When the toroid is deviated from the horizontal plane, the magnetic liquid causes the secondary winding voltages to correspondingly change.

Abstract: Disclosed herein is a fluidic clinometer for automatically operating servomechanisms according to the angular displacements of a structure on which the inclinometer is fixedly mounted for integral movement therewith.