Abstract: A compass which is self-compensating for dip of its pointer arms irrespective of variances in the earth's magnetic forces at different geographical locations includes a magnet disposed beneath respective proximal portions of the pointer arms so that the pointer arms are parallel to the magnetic field of the magnet, with the magnet constructed to be counterbalancing with regard to the earth's magnetic fields. In a preferred embodiment, the magnet comprises a plastic disk with magnetic particles embedded therein, the disk having a chordal portion removed therefrom immediately beneath one pointer arm, and a damper pan assembly is controlled by a lift arm to selectively dampen the movement of the pointer arms.

Abstract: A grain temperature monitor for use with one or more grain bins, the monitor including one or more temperature sensors, an analog sensor indicator unit, and a non-analog sensor indicator unit. The analog sensor indicator unit provides a signal when one or more of the temperature sensors senses a temperature in the monitored grain that equals or exceeds a predetermined reference temperature. In addition, an operator controllable switch can be manipulated to determine the approximate temperature of the highest sensed temperature. The non-analog sensor indicator unit provides a visual indication as to which of the temperature sensors then currently senses the highest temperature, without regard as to whether such sensed temperature exceeds the predetermined temperature threshold or not.

Abstract: A measuring bar for determining flatness and deviations therefrom comprises a rigid bar, and a plurality of support feet projecting from the bar. The support feet have free ends which occupy a common, flat plane, the free ends of each of the support feet defining a transverse supporting surface of essentially 0.005 to 0.025 inch across. Measuring devices are carried on the bar for measuring the spacing from the flat plane of at least one point on a target surface against which the support feet free ends rest, the measured point being spaced from the support feet.

Abstract: Apparatus and method for implementing a characterized thermal profile upon a temperature/time dependent process on any material or materials susceptible to such thermal processing in accordance with a closed loop environmental feedback system and a corresponding predetermined characterized thermal profile.

Abstract: The invention relates to a device for reproduction and tracing by forming an image of an original, at desired scale which is produced by at least one lens, on a screen on which a sheet of photosensitive materials, such as a picture film, or tracing paper is extended, comprising separate illumination systems for reproduction and tracing, wherein the illumination system for tracing is retracted in a retraced position located off the lighting space of the illumination system for reproduction, and turned over so as to eliminate spoilage of the quality of the reproduced picture by diminishing irregular reflection from the illumination system for tracing to the lens when a part of light from the illumination system for reproduction is emitted thereto during the reproduction operation.

Abstract: A template set for inscribing a plurality of ellipses with pencil, inking pen or other marking means is disclosed. The invention comprises a two-part unit for small ellipses, or a three-part unit for larger ellipses, enabling an individual ellipse or series or ellipses to be drawn, whether or not such ellipses have common foci or eccentricity. The device can further be used to draw ellipses of varying size and degrees of eccentricity, and having common foci. The device consists of an exterior holder, an interior holder, a large-ellipse guide portion and a small-ellipse guide portion. In the embodiment for drawing large ellipses, a shim is used to maintain the large-ellipse guide portion in spaced relationship from the drafting medium.

Abstract: A single-tone inverted toroidal whistle for producing a uni-directional output of about 135 decibels at 100 feet on axis at a frequency of about 420 hertz. A hollow cylinder having a closed base end is combined with a toroidal body to provide an annular sound chamber the working length of which determines the wavelength of sound generated by passage of air or steam under pressure through an annular slit formed in the interior of the cylinder and impinging against a spaced tapered lip on the inner cylindrical wall of the toroidal body.

Abstract: A integral plastic frame for holding a film slide includes a central window, a recessed bearing surface, which surrounds the window and serves to contact the film slide when it has been inserted to cover the window. The transparency as it is inserted and in its final position is guided between the bearing surface and the retaining elements facing the bearing surface. The retaining elements substantially consist of continuous retaining strips, which extend in the direction in which the film slide is inserted. The retaining strips are attached to mutually opposite sides of a central window of the integral frame member by means of narrow connecting webs, which extend at right angles to the direction in which the film slide is inserted. The plastic material of the frame member is so elastically flexible that an opening through which the film slide can be inserted is formed between the retaining strip and the bearing surface.

Abstract: A first body part having a rubber rim wheel and a second body part having a rubber rim wheel are interconnected by a vertical hinge. The first body part has a pencil holder between its wheel and the hinge and the wheels have distance measurement scales. An angle measurement scale is provided for the hinge.

Abstract: A sensor for detecting an interface of a liquid in a container comprises a transmitter and a receiver of ultrasonic waves, each situated outside the container, and coupled to the wall of the container by a strip waveguide. The transmitter is arranged to cause surface acoustic waves to propagate through a portion of the wall, and the receiver is arranged to detect waves derived from the transmitter. When the liquid is adjacent to the portion of the wall, mode conversion of the surface acoustic waves in the wall of the vessel into compression waves in the liquid causes a change in the energy of waves reaching the receiver.

Abstract: An optical apparatus for projecting a pattern on a first plane onto a second plane comprises a projection optical system disposed between the first plane and the second plane to form an imaging optical path, a structure for forming a space independent from the ambient space and filled with a gas between the first plane and the second plane in such a manner that the imaging optical path passes therethrough, the structure including a first transparent flat member perpendicular to the optic axis of the projection optical system and forming the entrance surface of the imaging light beam to the independent space and a second transparent flat member parallel to the first transparent flat member and forming the exit surface of the imaging light beam from the independent space, the gas filling the independent space having a refractive index different from the refractive index of the ambient space, and a device for regulating the distance between the first transparent flat member and the second transparent flat member

Abstract: The invention relates to an arrangement for remote ultrasonic temperature measurement. The arrangement employs a sensor, which in turn comprises an electromechanical transducer, a sensing element, and a hollow ultrasonic waveguide for coupling the sensing element to the transducer. The transducer is designed to propagate surface waves of a torsional or a radial shear mode upon the internal surface of the waveguide. The walls of the waveguide are made sufficiently thick, such that supporting clamps applied to the exterior of the waveguide have no adverse affect on interior wave propagation. The sensing element may be of either a hollow construction using internal surface wave propagation for protection of the active interior surface of the sensing element or of a solid construction in which the active outer surface of the sensing element may be exposed to the environment.

Abstract: Projecting device for presentation of pictures and of a kind which includes a lockable transport safety device (4, 10, 21) for members (8) which are movable for adjustment purposes and which are of such weight and form that they require the safety against shocks and vibrations. For the adjustment an adjustment device is provided having an operating member (17). The transport safety device (4, 10, 21) is so arranged that it for locking purposes requires a locking element (21). This locking element also is provided to alternatively accomplish a movement of the adjustment device (3) when operating the operating member (17) for the adjustment, whereas the adjustment device (3) being released from actuation from the operating member (17), when the locking element (21) is positioned in the transport safety device (4, 10). In this way no adjustment can take place, when the transport safety device is locked.

Abstract: A tire temperature measurement apparatus comprising a microwave receiver (9 or 11) sensitive to electromagnetic radiation in a waveband in the frequency spectrum 10 to 100 GHz and a directional antenna (5 or 7) coupled to the receiver input and responsive to radiation from a predetermined surface area only of the tire (1 or 3).

Abstract: A drawing aid for assisting in the marking of lines or other markings on sheet material incorporates a blade-like portion (2) which is connected with a location region (1A, 2A) which includes means (4, 5) deformable relative to the blade-like portion to be able to provide abutment surfaces which enable the aid to so co-operate with the actual edge of a sheet (8) of flexible or non-rigid material such as a sheet of paper as to use the edge (11) as the guide for the aid during the positional adjustment thereof to the location at which it is desired to draw lines or the like on the sheet (8). When the aid is engaged with a sheet edge (11) a part (1A, 2A) of the aid (1) presses on the sheet marginal edge (11A) to remove any buckles etc. and also to prevent any relative displacement of aid and sheet.

Abstract: A microfilm reader with a lens holder moved independently of a lighting unit at right angles in relation to the beam path by means of a drive unit. This renders it possible to correctly position any of a plurality of lenses arranged side by side in the lens holder in relation to the frame to be projected. Given that the lighting unit and the lens holder are capable of moving independently of each other, it is furthermore possible to shift the lighting unit into a position above the respective frame to be projected to obtain an image that is optimally illuminated.

Abstract: A sensing head of a measuring machine comprises three straight line guiding systems for respective x, y and Z directions. For weight compensation of each single straight line guiding system, a first spring pair is arranged between a fixed beam element and a beam of the first straight line guiding system. This compensates the weight loading the first straight line guiding system. Between the beam of the first straight line guiding system and a beam of the second straight line guiding system, a second spring pair is arranged which compensates the weight loading the second straight line guiding system. Between the beam of the second straight line guiding system and a beam of the third straight line guiding system, a third spring pair is arranged which compensates the weight loading the third straight line guiding system.

Abstract: A hand-held measuring device including an elongated base having a pair of opposed parallel metric measuring scales on the upper face thereof, a slider slidably mounted on the base having a linear indicator perpendicular to the axis of the base and a holder device for holding the stamp on the base under the slider while the slider is being moved from one end of the printed border on the stamp to the other. The left hand edge of the printed border of the stamp must be zeroed at the zero points of both scales using the indicator line. The slider is then slid to the opposite printed border on the face of the stamp while the holding means is held firmly so that the indicator line registers therewith. The precise dimension of the distance across the face of the stamp to the right hand printed border can then be read off of both scales. The indicator inscribed on the slider is perpendicular to the axis of the base. The holding device can be a thin flexible folded over piece of celluloid type plastic.

Abstract: The bowstring peep sight is inexpensive and durable and can be easily, rapidly and securely connected to the bowstring of a compound or non-compound archery bow without having to serve locking knots on the bowstring as with conventional peep sights. The peep sight is particularly useful with compound archery bows where the close proximity of multiple segments of bowstring to each other renders the serving of knots difficult and time consuming. Serving knots can slip, whereas the present peep sight is positively locked but easily loosenable and/or removable from the bowstring. The peep sight has a body defining a tapered peep and a peripheral string groove. The body may be partly cut away to expose the string groove to one or more movable connector plates which can be screwed thereagainst. Instead, the main body can be split into front and rear plates releasably secured against each other by external or internal screws, or have studs press-fittable into mating openings, trapping the bowstring therebetween.

Abstract: A hot air leak sensor for sensing jet engine bleed air leaks in an aircraft. Infrared detectors are combined with thermal re-radiating elements which are installed in air passages adjacent to the bleed air ducts and downstream of the region where a bleed air leak may occur. The elements are approximately 50% transmissive and 50% absorptive to infrared radiation with wavelengths within the range of approximately 4 to 20 micrometers. Incident radiation within the field of view of the detector is both transmitted and absorbed for re-radiation to the detector. If no incident radiation within the sensor field of view is available, the re-radiating element still responds to the increased airstream temperature resulting from the bleed air leak and supplies radiation to the detector to provide detection of the leak.