Abstract: An illuminated spirit level containing fiber optic cables for the transmission of light from the self contained light source to the level vials is disclosed. The lighting system provides for several improvements over other such devices, including a light chamber with a highly reflective interior for containment of the light source and fiber optic cable ends, and opposite cable ends formed to closely fit the contours of the level vials for greater light transmission efficiency. Provision is made for recharging the batteries, and inadvertent actuation of the system may be prevented by locating the switch within an aperture contained within the level frame, a momentary on or pushbutton type switch, and/or the inclusion of a delay circuit providing automatic deactivation of the circuit when a predetermined time has elapsed after activation. The electrical components may be secured within the level by cover plates, which also provide secure storage for a spare electrical bulb.

Abstract: A magnetic compass is illuminated by a light emitting diode. The compass is nclosed in a case made of a lightweight, plastic composite material. The light-emitting diode is energized by a low profile, nonmagnetic battery connected to the light emitting diode through a nonmagnetic microswitch operated on the exterior of the casing by a pushbutton. The compass has a compass rose with strips of phosphorescent material disposed thereon, a rotatable bezel with a strip of phosphorescent material thereon and a lid having a sighting slot therein traversed by a cross hair. Located at the bottom and top of the cross hair are additional strips of phosphorescent material so that the compass may be utilized in the dark. The phosphorescent material may be charged by ambient light and by light emitted by the light emitting diode.

Abstract: An illuminating device to be used in association with an instrument to facilitate reading indicia thereon in low light/dark conditions. The device can be attached to a single instrument or a combination of consolidated instruments-gauges. The illuminating device is normally attached to an associated instrument in a generally overlaying relationship to the instrument face; and can be used universally with instruments of different sizes and configurations within various classes of instruments.

Abstract: There is provided an optical viewing system, which is preferably a compass which eliminates the parallax and sighting problems of prior art optical systems. The compass includes a beam splitter which displays a sighted image both on a reference screen and a free-floating magnetized sphere or other moving surface. The sighted image on the reference screen and on the sphere are superimposed upon each other when viewed through one facet of the beam splitter. In this manner parallax is eliminated, thus the direction and elevation of the image may be readily and accurately determined.

Abstract: A device that may be of different shapes and sizes to function as a level that emits an audio and visual signal when the device is level or parallel with gravity. It will also emit the same signals when the level is put in a vertical position and the device is plumb in one dimension; while at the same time will emit a different audio and visual signal when the level is moved and the bubble or amalgam will flow to the center of the other glass tube thus indicating that the other plane is level. In essence, both sets of signals will activate when the level is in true vertical position. The audio and visual signals are activated by D.C. current supplied by a dry cell battery. The liquid leveling agent is a drop of amalgam enclosed in a glass tube that is embedded in the body of the level.

Abstract: A vertical alignment apparatus has a light and a light fixture attached to a cable to be lowered into the cylinder to be aligned. A disk mounted on top of the light fixture and centered about the light fixture and the cable causes the light emitted from the light fixture to form a halo between the disk and the wall of the cylinder. A tripod on top of the cylinder movingly centers the light, light fixture and disk in the cylinder. The method of the invention involves lowering the apparatus into the cylinder. The light fixture is activated to create a halo of light around the disk. The light fixture is then raised up the casing, and the casing is adjusted until the halo has circular consistency.

Abstract: An electronic display device for presenting directional information to the operator of a motor vehicle. The display simultaneously shows current vehicle direction of travel as well as the relative directions of the 4 major compass axes by converting the direction information from an electronic flux gate compass. The device is further optimized to reduce the number of pin connections to the display and associated driver complexity and is readily applicable to LED, LCD or vacuum fluorescent type display elements.

Abstract: An improved plumb bob having a downwardly directed light beam to indicate the point directly below the plumb bob. The light is operated by batteries within the plumb bob and, in order to prevent undesired draining of the batteries, the light is switched on and off by the weight of the plumb bob acting on the line. The switch is activated by a conductive spring held within the plumb bob.

Abstract: A level constructed of clear acrylic plastic including a piece of colored acrylic plastic which serves as a light collector and a continuous passageway in the clear acrylic which reflects the light collected by the piece of colored plastic. By partially filling the passageway with liquid, a line of reflected light appears on the wall of the passageway above the interface between the liquid surface in the passageway and the unfilled portion of the passageway, whereby the level is easier to read than ordinary bubble type levels.

Abstract: A plumb bob having a built-in light source and electrical power supply including a main barrel, a conical tip and a screw cap. Tightening of the screw cap closes the circuit for operation of the light source. A suspension line extends from the cap and is stored when not in use between the cap and barrel where it serves to prevent tightening of the cap and light source actuation.

Abstract: A precision level embodying solid state electronics is disclosed. A level body portion contains chambers for paired light emitting diodes operable to indicate angular deviations from true horizontal and true vertical over desired ranges. A mercury droplet in each compartment is in contact with an arcuate conducting strip leading to a battery terminal of one polarity. Upon angular displacement of the level, the mercury droplet sequentially contacts light emitting diode leads of like polarity. The light emitting diode leads of opposite polarity are connected through a common conductor element and an on-off switch of the level to a battery terminal of like polarity. The same switch is operably connected with the groups of light emitting diodes used to indicate angular deviations from the true horizontal and true vertical. The light emitting diodes may be embedded in a clear transparent medium or in variously colored translucent elements.

Abstract: A recreational or sportman's compass is comprised of an inner vial including a compass needle which together with an azimuth ring is resiliently mounted within a housing so as to be rotatable together or independently of one another. The vial is assembled together with the outer azimuth ring and retainer in such a way as to permit assembly of the parts into snug-fitting concentric relation to the housing without the necessity of positively fastening or affixing the vial to the housing.

Abstract: An electronic compass for vehicles such as automobiles comprising a float mechanism including a permanent magnet for following the earth's magnetic field and four Hall effect sensors for detecting magnet orientation at points corresponding to the cardinal compass points. The Hall effect sensors are connected to triggering circuits having overlapping thresholds so that two circumferentially adjacent sensors and sensor trigger circuits cooperate to indicate not only the corresponding cardinal compass points but also the secondary compass point intermediate the cardinal points. The sensor trigger circuitry is connected to a two-character multiple-segment display for indicating vehicle orientation at either one of the four cardinal compass points or one of the four secondary compass points intermediate successive cardinal points.

Abstract: Disclosed is a structure of a telescope with compass which indicates the direction in which the telescope is pointed, at the periphery of the field of vision of the telescope. Referring to the compass used for the telescope: a magnet is provided in a compass direction indicating globe on whose outer circumference directions are indicated. This direction indicating globe is supported so as to float in a case containing a lubricating liquid such as oil, etc. This compass is attached to the body of the telescope (specifically, a pair of hand-held binoculars, etc.). Then, the compass direction indication of the direction indicating globe appears as an image at the same focal point as the focal point of the objective lens of the telescope. Referring to other forms of telescopes: the direction indication is especially applicable to a telescope attached to a stand. A gyrocompass fixed to the arms supporting the body tube is connected to a luminous diode or crystalline liquid indication means, etc.

Abstract: A geodetic compass having a mirrored cover that has the dual purpose of providing means for reading the compass needle orientation for geodetic purposes, while at the same time having cross hatch diffractional sighting means incorporated in said cover and mirror for utilizing said mirror for emergency signalling purposes.

Abstract: In order to correct errors in the reading of a graduated scale, especially on a compass card driven by a damped gyroscopic system, the scale is juxtaposed with a block having slits simultaneously alignable with different scale graduations and illuminable by respective light sources within the block. The light sources can be selectively energized by a rotary switch whose bank contacts are connectable via a changeover switch to either of two groups of light sources for positive or negative deviations from a reference position; the slit so illuminated serves as a pointer by coacting with a confronting scale graduation.

Abstract: A frame-setting apparatus that is designed to be used in leveling frame structures having adjacent side-frame members that must be set in a close parallel relationship to their opposite sides, whether they be in a vertical or a horizontal position, wherein the apparatus comprises an elongated level having a plurality of spirit-level units spaced along the length of the level in the usual manner to provide a level reading in both a vertical and a horizontal position, and wherein flat elongated sections of mirrors are interposed between the spirit levels to reflect from one side frame member to the adjacent frame member, the mirrors being provided with a center-leveling line marked longitudinally along the length of each mirror, so as to aid in the alignment of a corresponding frame member when sighted in the mirrors.

Abstract: Improved mounting means is provided for mounting a top viewable liquid vial in a level having an I-beam type frame provided with a through opening in the web communicating with a notch in the adjacent horizontal working surface, the mounting means including a transparent shroud for the vial having a bight portion extending around the vial below the notch forming a magnifying lens and side walls forming side windows protecting the vial. The shroud is clamped between a pair of identical mounting caps which also are clamped to the web around the periphery of the through opening thereby enclosing the shroud and vial assembly and positioning it in the through opening to permit viewing of the vial from the top and sides.

Abstract: Improvements are disclosed in the pattern cone of the magnetic compass as described and claimed in copending application 769409, Harold T. Lyman, Jr., now U.S. Pat. No. 4,132,113. Simpler apparatus for trimming the sensor outputs of the sine and cosine of the angle between the craft's actual heading and the desired heading, are described and claimed.

Abstract: Level indicating devices wherein at least a side portion of a bubble cavity is defined by a reflecting surface having at least a linear cross section lying generally in a plane aligned with or paralleling a light source and a bubble image observer (i.e. person or sensor).

Abstract: A compass having a magnetic element pivotally mounted in a housing, the housing including a light source and one end of an array of fiber optic bundles and the element carrying a reflector and/or an aperture to selectively permit light from the source to reach a selected one or more of the fiber optic bundle ends within the housing in dependence upon the orientation of the element relative to the housing about the pivot axis of the pivotal mounting.

Abstract: A viewing device for use in conjunction with a level of the type having a see through bubble housing comprising two opposed windows and a bubble chamber situated therebetween. The device includes a base containing a luminescent panel that is arranged to seat in contact against one of the bubble housing windows whereby the panel illuminates the bubble chamber, a post perpendicularly secured to the base and extending upwardly beyond the other bubble housing window and a light shield slidably mounted upon the post and being arranged to seat in locking engagement against the other bubble window, the light shield containing a viewing aperture through which the bubble chamber can be seen and a mirror adjustably supported in the shield to permit off axis reading of the bubble.

Abstract: A level indicator which features a pendulum-style magnified dial and a versatile magnetic swing plate or base. The swing plate is pivotally and laterally moveable with respect to the main casing of the level indicator to provide a more stable and accurate adherence to the surface whose alignment is being checked. The magnetic surface of the swing plate cooperates with a coplanar magnetic face of a fixed-position heel plate to add further stability and accuracy. The level indicator features a hairline-bearing suspended mass in the form of a magnifying lens, the hairline being preferably scribed along its outer convex surface to eliminate parallax errors. The indicia-bearing dial plate may be edgewise illuminated by one or two light sources internally positioned and powered. Two substantially identical viewing faces are preferably provided to increase versatility.

Abstract: An orientation system adapted to be mounted within a vehicle, comprising a display including a rotational heading indicating compass card fabricated from an image retaining electronic display panel responsive to bearing data signals.

Abstract: An automatic lighted level and a angle finder has a frame provided with a planar surface arranged for abutting against an object the orientation of which is to be determined or adjusted. An electrically energized visual indicator is mounted in the frame of the device for indicating when the planar surface of the frame is oriented at a predetermined angle by the closing of an angle-sensing switch including a reel assembly adjustably mounted in an opening provided in the frame and connected to the indicator and to a source of electrical power for energizing the indicator by closing an electrical circuit connecting the indicator to the source of electrical power when the switch is rotated relative to the frame to an angle corresponding to the angle of an object whose angular orientation is being determined. Alternatively, the planar surface may be placed on the object and the latter moved until its orientation corresponds to a predetermined angle set on the switch.

Abstract: An instrument for indicating or checking the angular position of an object. A movable part is mounted on a stationary part; said parts have a pattern of equally wide parallel lines separated by interspaces. When the parts overlap in use of the instrument the line patterns form a moire pattern to indicate the angular position of the object.

Abstract: A device that may be of different shapes and sizes to function as a level that emits an audio and visual signal when the device is level or parallel with gravity. It will also emit the same signals when the level is put in a vertical position and the device is plumb in one dimension; while at the same time will emit a different audio and visual signal when the level is moved and the bubble of amalgam will flow to the center of the other glass tube thus indicating that the other plane is level. In essence, both sets of signals will activate when the level is in true vertical position. The audio and visual signals are activated by D.C. current supplied by a dry cell battery. The liquid leveling agent is a drop of amalgam enclosed in a glass tube that is embedded in the body of the level.