Abstract: An electrical safety plug having two prongs receivable in a complementary socket having two terminal holes, the plug and socket combination being polarized so that the relationship between the prongs and terminals is non-reversible. The plug body has integral therewith a safety tab so positioned that when the plug is correctly inserted in the socket, the tab lies under the body of the socket. The tab blocks insertion when the user seeks to make an incorrect insertion in the complementary socket or in the event the user tries to plug into any other socket.

Abstract: A silencer adapted to suppress the audio output of a radio or television set during commercial breaks in a program. The silencer which requires no wiring changes in the set includes a probe insertable in the existing earphone jack. The probe is constituted by a truncated tubular plug whose length falls short of the flexible switch arm of the jack that normally engages a contact arm to connect the audio signal line to the loudspeaker, the plug having a retractable plunger therein. When the plug is advanced by a local actuator, it engages the switch arm of the jack to flex it away from the contact arm to cut off loudspeaker sound, the sound being restored when the plunger is retracted. The local actuator of the plug is coupled to a remote actuator which when manually-activated acts selectively through the local actuator to advance or retract the plunger to cut off sound at the outset of a commercial break and to restore it at the conclusion thereof.

Abstract: An optical micrometer measuring system adapted to gauge minute distances between spaced points on an object under test and to indicate the results in digital terms. The system includes a compound microscope having a stage for supporting the object, the object being illuminated and being focused by an objective onto a real image plane to produce an aerial object image which is viewable in magnified form by an operator through an eyepiece. Associated with the microscope is a projector which creates an illuminated image of a pointer, optical means being provided to superimpose the pointer image over the aerial object image. Operatively coupled to the projector is a micrometer controllable by the operator to translate the pointer image between any two points of interest on the object image. The distance travelled by the pointer image is digitally indicated by an analog-to-digital read-out coupled to the micrometer to provide the desired reading.

Abstract: An electromagnetic flowmeter in which fluid to be metered passes through a flow tube to intersect a magnetic field whereby the voltage induced in the fluid is transferred to a pair of electrodes mounted in the flow tube to yield a flow-induced signal having a random noise component. This field is established by an electromagnet supplied with an excitation current creating a magnetic field that is alternately turned "on" and "off" at a low frequency drive rate. The resultant flow-induced signal is sampled during each "on" and "off" field condition, successive differences therebetween serving to develop an analog output signal having a random noise content.

Abstract: A galvanometer-type motor for driving an optical element to deflect or otherwise modulate a radiant energy beam, the motor having a favorable mass-to-torque ratio that renders it capable of oscillating at a high-frequency rate and of performing other movements in accordance with an input current. The motor includes a permanent magnet rotor and a soft magnetic stator having a pair of split pole pieces extending from a pair of arms that are joined by a bridge forming the core of a field coil. The split pole pieces are disposed on opposite sides of the rotor whose axis of rotation is centered with respect thereto, the rotor being supported for rotation by means including a torsion spring acting to return the rotor to its neutral rest position. In the neutral position, the split poles of each piece straddle the end poles of the rotor on the related side thereof.

Abstract: A high yield technique for converting round logs of balsa or other species of wood of relatively small diameter into large rectangular panels, the percentage of log volume that is converted being substantially greater than with prior techniques. The logs are radially sectioned into sectors having the same apex angle. Each sector is then longitudinally cut at its apex and arc to define a truncated feedstock piece whose cross-section is that of an isosceles trapezoid, the feedstock pieces being of variable width depending on the diameters of the logs from which they are derived. The pieces are fitted together in a complementary manner to create uniform layers which are superposed to form a stack defining a dry block assembly. The end pieces in each layer are constituted by feedstock piece halves to present a vertical block edge. All feedstock pieces in the dry block assembly are then wet-coated with a curable adhesive.

Abstract: A Tangram game assembly constituted by two sets of Tangram pieces capable of creating a variety of geometric or representational figures. Also included is a deck of cards, each having printed thereon a Tangram puzzle figure and the solution thereto at a position at which it is obscured in play. In play, a card is withdrawn from the deck and its front face presented to the players who with their respective sets of pieces then race to recreate the figure. The player who is first to succeed is awarded the card. Cards in the deck are played, the player who gains the greatest number being the winner. Any number of cards may be played depending on how long the players would like the game to last.

Abstract: A stabilized vortex-shedding flowmeter for accurately measuring the flow rate of a liquid or gas conducted through a flow tube. The meter includes a front obstacle transversely mounted across the tube with its longitudinal axis normal to the flow axis of the tube. Supported behind the front obstacle and spaced therefrom by a gap is a rear obstacle constituted by a pair of parallel beams symmetrically disposed with respect to the flow axis and lying in a plane normal thereto. In operation, as the incoming fluid stream is divided by and flows past the front obstacle, a stagnant zone is created in the gap. This zone is initially aligned with the flow axis; but as vortices are successively detached from the front obstacle and appear alternately on either side of the gap, the low pressure produced by each vortex act to draw the stagnant zone in front of the beam adjacent thereto, the fluid then going around and past the other beam and imposing a drag force thereon.

Abstract: A needle threader usable by those who find it difficult to thread a needle in a conventional manner. The threader is constituted by an upstanding blade whose lower end is anchored and whose upper end or head is V-notched to loosely receive within its trough the end of a yarn or filament to be threaded. The width and thickness of the head is such as to be passable through the eye of the needle to be threaded. When the eye of the needle is brought over the head to a point below the trough of the notch, the thread is formed into a loop whose feet are clamped by the eye against the blade, and when the needle is thereafter retracted from the head, it carries the loop with it. Finally, the operator pulls the loop out of the eye and thereby threads the needle.

Abstract: An electromagnetic flowmeter wherein a liquid to be metered is conducted through a flow tube to intersect a transverse magnetic field produced by an electromagnet, the resultant signal induced in the liquid being transferred to a pair of electrodes mounted at diametrically-opposed points on the tube. To avoid spurious signal components arising from stray couplings between the electromagnet and the loop constituted by the electrodes and the liquid bridging the electrodes, the coil of the electromagnet is energized by a low-frequency wave whose frequency is well below the standard a-c power line frequency. And, to avoid noise components produced when the liquid being metered is a slurry containing solid particles which impinge on the surface of the electrodes, the electrodes are fabricated of or coated by a carbide metal or an alloy thereof whose metallurgical hardness is such as to substantially reduce the generation of such noise components.

Abstract: An electromagnetic flowmeter system whose electromagnets are excited by a direct-current source through switching means operating at a predetermined drive frequency to generate a pulsatory current establishing a magnetic flux field in the flow tube through which the fluid to be measured is conducted. The fluid intercepting this field induces a pulsatory voltage in the metering electrodes mounted at diametrically-opposed positions on the tube. The electrode voltage is applied to an analyzer which includes a sampling switch operating in synchronism with the drive frequency to extract pulses from the electrode voltage during the magnetic flux steady state intervals thereof. These pulses, which are rich in harmonics, are fed through a filter that selects one of the harmonics to yield a harmonic signal which is demodulated to produce an output signal free of disturbances.

Abstract: A signal generator for reducing the influence of fluctuations in flow rate distribution in a fluid passing through the flow tube of an electromagnetic flowmeter, which fluid intercepts a magnetic field therein to induce an emf which is transferred to the meter electrodes, thereby yielding a signal as a function of flow rate. To this end, the tube is provided with auxiliary electrodes disposed at arbitrary positions at which the potentials developed thereon are equal to each other when the existing flow rate distribution is symmetrical with respect to the flow tube axis, the auxiliary electrodes being interconnected.

Abstract: An agricultural spreader device for spreading seed and other granular material, the spreader being constituted by modular assemblies which are attachable to a central carrier assembly mountable on an agricultural machine such as a tractor. Each modular assembly includes a cylinder supported by rollers, the amount of material spread being determined by the adjustment of the cylinder speed. The lower opening of a distribution hopper is located in front of the cylinder top.