Abstract: A method and a device for measuring the maturity of concrete, in which the heat generated by the setting of the concrete causes a special liquid to evaporate and the amount of evaporated liquid is taken as a measure of the concrete maturity. The liquid is contained in a closed capillary tube placed on a scale. For measuring purposes the capillary tube is broken at a well-defined point, and capillary and scale are then placed in a casing containing an absorbing agent for the evaporated liquid. The casing is hermetically sealed and pressed into the concrete. For reading purposes the casing is opened and the scale with the capillary is removed to determine the level of the liquid column and thus the maturity of the concrete.

Abstract: A loading device for a recording and/or playback apparatus, for example, a record-disc player or a tape cassette apparatus, comprises a movable loading support onto which a holder containing a record carrier can be slid by feed rollers driven by a motor. The loading support is slidably supported between two fixed, parallel, vertical guide plates by pins on the support sliding in L-shaped guide slots in the guide plates, each slot having a vertical section extending downwardly from a horizontal section. Slidably supported on the outer sides of the guide plates for horizontal movement in vertical planes parallel to the planes of the guide plates are two drive plates having inclined slots in which the pins on the loading support slidably engage.

Abstract: A method and apparatus for evaluting the performance of a heat exchanger are described. Water is supplied to the heat exchanger at a known mass flow rate and temperature. The water is directed to traverse a flow path of the heat exchanger. The water is then heated and redirected into another flow path of the heat exchanger in heat exchange relation with the first flow path. The temperature change of the water over a flow path is measured to determine the performance of the heat exchange. The water flow rate and incoming water temperature may be fixed to make a single discharge temperature measurement sufficient to calculate heat exchager performance.

Abstract: A door brace alarm apparatus for resisting movement of a door and for providing a sound alarm when such movement of the door is attempted. Two slideably connected shaft members are adjustable for angular placement between the door knob and the floor. A bifurcated yoke and a floor support retain the door brace alarm in position by contact with the door knob and floor. A pivotally mounted alarm housing connected to one of the shaft members houses an alarm retainer which provides for extension adjustment by threaded cooperation with a cavity in the alarm housing. The alarm retainer houses the sound generator and adjusts to position the sound generator in juxtaposition with the door so that it will emit an alarm sound upon impact by the door.

Abstract: A marking device for aiding in locating a fire hydrant or the like, in the event that it is covered by snow, or underbrush, or some similar concealing environment. The marking device comprises a mounting bracket adapted for attachment to the fire hydrant and an elongated stem projecting upwardly from the mounting bracket so as to extend for a predetermined height above the hydrant to which it is attached. The stem preferably has a flag mounted thereon for enhancing the visibility of the marking device. The mounting device and the stem are so constructed and arranged that the stem can be swung from its generally upright position to a downwardly angled position, and thus out of any interfering relationship with the conventional operating nut on the hydrant.

Abstract: There is provided a differential amplifier having a plurality of inputs connected through input resistors to a summing junction at the inverting input of a differential amplifier which also has a negative feedback path having a feedback resistor. One of the input resistors is connected to the output signal of the primary element or transducer. A second of the input resistors is connected to a zero compensating signal which varies with changes in the temperature of the transducer from a certain value at a reference temperature. A third input resistor is connected to a fixed signal of a value which is adjusted to correspond to the certain value of the compensating signal at the reference temperature but of opposite polarity so as to tend to cancel the compensating signal when the transducer is at the reference temperature. The combination of the three inputs then produces an output from the differential amplifier corrected for changes in the zero of the measurement due to temperature changes.

Abstract: A tire deflation warning device having an arm carried by the rotating wheel and normally held retracted by a plunger activated by tire air pressure. Upon deflation the plunger releases the arm to be moved radially outwardly by centrifugal force so as to contact an element on the vehicle body and sound an alarm.

Abstract: For loading a record disc on the turntable of a record-disc player, a loading device is provided which comprises a movable loading support for supporting a holder containing a record disc. The loading support is slidably supported between two fixed, parallel, vertical guide plates by pins on the support sliding in L-shaped guide slots in the guide plates, each slot having a vertical section extending downwardly from a horizontal section. Slidably supported on the outer sides of the guide plates for horizontal movement in vertical planes parallel to the planes of the guide plates are two drive plates having inclined slots in which the pins on the loading support slidably engage. By cooperation between the inclined slots and the pins the drive plates can move the loading support, guided by the L-shaped slots in the guide plates, along a horizontal path and down a vertical path to deposit the record disc supported on the loading support on the turntable.

Abstract: An apparatus for indicating tire pressure is disclosed which indicates whether the tire pressure in a pair of pneumatic tires is low, normal or excessive. The apparatus includes a valve body which is operatively connected to each of the tires and comprises a valve which longitudinally moves in the apparatus responsive to air pressure. The valve is operatively connected to a scale pan having an arcuate display portion at one end thereof. The display portion on the scale pan includes colored rectangular segments which are visible through a sight window in the apparatus. The scale pan pivots in response to valve movement and the colored segment visible in the sight window indicates whether the tire pressure is low, normal or excessive.

Abstract: A flexible stick tank gauge is made of a thin metal or plastic tape. The tape is sufficiently thick to be self-supporting when held vertically from the lower end. Alternatively, the tape is curved to be a narrow sector of a cylinder. Measuring indicia are applied to at least one surface of the tape. The tape remains flexible at extreme environments of temperatures and will not break in normal use such as airline fuel measuring operations.

Abstract: An aircraft warning marker for use on a suspended high voltage wire is provided. The marker is composed of a substantially smooth, continuous electrically insulating body and a substantially electrically continuous electrically conducting layer disposed adjacent substantially the entire outer surface of the electrically insulating body. The insulating body and the conducting layer have a sufficiently low combined weight so that the marker is supportable on the wire. The electrically conducting layer of the marker is intended to be electrically connected to the wire.

Abstract: An apparatus adapted to be mounted on a surface grinding machine is provided for testing abrasive grains in single-grit scratch tests. To permit specimen preparation and scratching to be carried out on a single machine without changeover and without reclamping the specimen, and to maintain the infeed in the scratching operation constant by giving the specimen a contour corresponding to the cross-feed error, a belt grinder and a scratching device comprising a support disk, mounted by means of a main flange and a counterflange, and a scratching disk mounted on the main flange and carrying a single grain secured to its periphery along with a force-measuring system disposed thereunder, are designed as a structural unit adapted to be mounted on the spindle of the surface grinding machine, with a belt tensioning arm mounted to the headstock.

Abstract: As a caddy is inserted into the player to load a record therein, it displaces the carriage locking lever to its retracted position to release the carriage. The record retaining spine of the caddy holds the carriage locking lever at the retracted position thereof as long as the record/spine assembly is inside the player. Upon removal of the record/spine assembly from the player, the carriage locking lever moves to its advanced position to arrest the carriage.

Abstract: A two-wavelength I.R. pyrometer for monitoring the rapid heating of materials by C W lasers or electron beams. The I.R. radiated from the material is separated into two closely adjacent wavelengths and signal values representative of those wavelengths are obtained. These signal values are then processed through an electronic circuit where the signal value of one of the signals is held substantially constant by a feedback control while the other signal value is influenced by approximately the same feedback control applied to the first signal value and wherein the resultant signal values are then processed through a circuit determining a ratio of one signal value divided by the other. This is then a measure of the temperature of the material. Also disclosed is a chopper wheel for a two-wavelength I.R. pyrometer. The wheel has a plurality of circumferentially extending I.R. filters of alternating wavelengths (.lambda..sub.1, .lambda..sub.2).

Abstract: Temperature indicating apparatus for sensing overheating at a pair of terminals on an electrical power line comprises a pair of thermocouples, each thermally coupled to and electrically isolated from a different one of the terminals, and a light emitting diode (LED) coupled to the output of the thermocouples through a conditioning circuit. An excessive temperature rise at either terminal causes the output voltage of the thermocouple coupled thereto to increase, thus causing the LED +o to be lit and to provide a visual indication of overheating. A meter display may be provided to show the actual temperature of the terminals in response to thermocouple voltage output. A method for determining heating at a termination without physical intervention comprises determining the rate of temperature rise of the termination for a known current therethrough and comparing the rate to a predetermined rate threshold.

Abstract: Presented is a method and means for monitoring the angle of attack of an airfoil and displaying the monitored angle of attack as a visual reference to the pilot.

Abstract: A surgical drainage unit is provided for draining fluids from the body of a patient wherein the suction pressure, applied through a suction inlet of the unit to draw fluids into the unit, is incrementally controlled and a direct indication of the applied suction pressure is afforded. A device which contracts responsive to an increase in suction in a collection chamber of the unit is equipped with an indicator vane that cooperates with a fixed scale to indicate the amount of movement of the bellows and hence indicate the suction within the collection chamber. A manually adjustable control valve incrementally controls the amount of air admitted to a suction line within the unit to thereby control the applied suction. A negative pressure relief valve is also provided so that excess negativity within the inlet tube can be manually relieved.

Abstract: A foldable traffic warning cone utilizes a first panel of generally fan shape having triangular faces joined at adjacent sides along face folding lines. The first panel has opposite free sides which interconnect to fold the first panel into an upright polygon. The triangular faces of the first panel have bottom ends with extending flaps which cooperate with a second panel having a number of sides commensurate to the number of faces on the first panel and which forms a base for the first panel. The second panel has wings extending outwardly from each of the sides and which are foldable to provide a wall extending about the base. The wings also trap the flaps and thereby connect the upright polygon and the base together. The warning cone can be selectively folded and unfolded for use and storage.

Abstract: A tire monitor for use with a pair of pneumatic tires comprising a body member having a diaphragm valve mounted in a first chamber formed therein defining first and second chamber portions. A spring is provided in the first chamber portion for yieldably urging the diaphragm valve towards one end of the body member. A valve cap is secured to the other end of the body member and has first, second and third air passageways formed therein. A valve is connected to the third passageway for permitting air under pressure to be supplied to the second chamber portion at times. The diaphragm valve prevents communication between the first and second air passageways when the diaphragm valve is in a first position and also prevents communication between the third passageway and the first and second air passageways when the diaphragm valve is in its first position.

Abstract: When a steel sheet or the like is heated in a furnace to a temperature somewhat higher than the room temperature and is still or moved, its temperature can be measured by detecting the radiant energy therefrom. The measurement is normally difficult due to the influence of background noise of radiant energy from the surroundings, change of the transmittance factor of the environment or atmosphere for radiant energy, and change of the emissivity of the object to be measured.