Abstract: A steam generation system employing a flash tank feeding low-pressure steam to a compressor controls surges in the compressor by calculating the amount of steam generated based on the temperature change and flow of water passing through the flash tank and modulates the flow rate in order to maintain the steam flow above a surge limit. If increasing the water flow rate is incapable of producing enough steam to avoid surges, a recycle control recycles steam from the output of the compressor back to the flash tank. A further embodiment of the invention permits using an auxiliary source of low-pressure steam to augment the steam produced in the flash tank while maintaining the total steam flow at a level sufficient to avoid surges. The steam flow may alternatively be derived from the differential pressure between outlet and inlet of the compressor.

Abstract: An apparatus for pumping a liquid stored under pressure without pressure-induced, liquid leakage during seal failure. The liquid or slurry being pumped is usually of a type that is difficult to handle, e.g., liquids which are volatile, poisonous, corrosive or a combination of these characteristics.The apparatus comprises in combination a vessel capable of containing a liquid under pressure; a vertical pump with its inlet port in communication with the vessel; an equalizing line connecting the shaft housing of the pump with the vapor space of the vessel; and a shaft seal located within the pump above the equalizing line connection so that the vessel and the shaft housing can be pressure-equalized during seal failure.The apparatus further provides pressure sensitive switching means so that the pump can be isolated upon occurrence of a specified pressure change within the vessel.

Abstract: An axial thrust balancing system including a sleeve for balancing an axial thrust applied to a rotary shaft and a bush defining therebetween a clearance having arranged therein at least one pressure chamber for dividing the clearance into a plurality of smaller clearances. The axial division of the clearance reduced the ratio of the axial length of the clearance to the diameter of the sleeve and stabilizes the bearing characteristics of a film of fluid in the clearance, thereby inhibiting the generation of a self-excited vibration of the shaft up to a high rotation velocity.

Abstract: A horizontally split casing of a turbo machine, such as a centrifugal compressor, including one half casing formed with scroll grooves on an inner peripheral surface thereof, and the other half casing formed with cutouts in portions thereof corresponding to outlet scrolls. A second casing formed on an inner peripheral surface thereof with scroll grooves is attached to the other half casing in a manner to enclose the cutouts. The horizontally split casing of this construction is low in cost and yet enables a compact size and a light weight to be obtained in a horizontally split casing of a turbo machine.

Abstract: Mechanical collective pitch control system for a circulation control rotor system aircraft utilizing an axially moveable pneumatic system plenum 32 in the collective pitch control system.

Abstract: An oil pump assembly having an adjustable production rate and capable of long stroke, low stroke per minute pumping rates, comprising a reciprocating pumping rod in a well hole, a counterbalancing mechanism for reducing the power needed to pump oil by the pumping rod, a driving mechanism to drive the reciprocating pumping rod and the counterbalancing mechanism, including a first cable and a second cable, to drive the reciprocating pumping rod and the counterbalancing mechanism, respectively, a speed control for the driving mechanism, and a dwell mechanism for the driving mechanism.

Abstract: A pump primarily intended for use in a portable ventilator. The pump includes a piston-cylinder arrangement in which the piston is reciprocally moved within the cylinder by rotating a shaft. The shaft is threaded and mounted for rotation within the cylinder at a fixed location along the axis of the cylinder. The piston has an aperture through its center and the shaft extends substantially between the end walls of the cylinder and through the center of the piston. The piston is held against rotation relative to the shaft and cylinder by a collapsible hinge and is attached to the shaft by an arrangement including a ball nut and sealing nut. The piston forms a variable volume, working chamber with one end of the cylinder and in operation, the shaft is selectively rotated to move the piston toward and away from the end wall. This positioning of the shaft within the cylinder reduces the overall size of the pump and specifically adapts it for use in a portable ventilator in which size limitations are critical.

Abstract: A transducer with which mechanical rotary motion can be interconverted with the flow of an electro-rheological fluid. Two, electrically conductive, movable, conveying surfaces are partly disposed in parallel confrontation thereby defining a fluid transfer path. A fluid transfer port is located at each end of the fluid transfer path through which electro-rheological fluid can enter and leave the transducer. The conveying surfaces are electrically connected to a voltage source and movable by means of a rotor to which they are connected. On application of a voltage difference between the conveying surfaces the electro-rheological fluid gells after which rotation of the rotor will urge the fluid along the transfer path and vice-versa.

Abstract: An improved pump assembly is used to supply fuel to an aircraft engine and includes a positive displacement pump which supplies fuel during low speed operation of the pump assembly and a centrifugal pump which supplies fuel during relatively high speed operation of the pump assembly. The positive displacement pump has a plurality of vanes connected with an impeller of the centrifugal pump. The vanes are forced radially inwardly against a stationary cam surface by fluid pressure. The fluid pressure is conducted from an outlet of the positive displacement pump through a passage in the impeller of the centrifugal pump to pressure chambers disposed at outer ends of the vanes. By providing the fluid pressure passage in the impeller of the centrifugal pump, the axial length of the pump assembly tends to be minimized. The positive displacement pump is rendered ineffective to pump fluid when the output pressure from the centrifugal pump equals the output pressure from the positive displacement pump.

Abstract: A rotary fuel injection pump having a rotary charge pump and a stroke control mechanism for variably limiting the outward stroke of a pair of diametrically opposed reciprocable pumping plungers of the charge pump for controlling the fuel charge measure delivered by the charge pump. Several embodiments of a stroke control mechanism are disclosed which include a generally U-shaped abutment yoke mounted within a diametral slot in the pump rotor for engagement by inclined ramps on the outer ends of the charge pump plungers and axially adjustable within the rotor slot for variably limiting the outward stroke of the plungers.

Abstract: A novel handle means for compressor units adapted to appropriately engage the charge, discharge, and suction outlets of a standard, lightweight, portable compressor unit. Semi-rigid tubing, e.g. copper tubing, is appropriately contoured about the body of a standard compressor unit to form a handle means with which the compressor unit may be conveniently transported. The novel configuration of the handle means herein disclosed conveniently positions the suction, charge and discharge outlets of a compressor unit for convenient connection with appropriate hose attachments.

Abstract: A teat spray system for installation in an automatic milking parlor for spraying the teats of cows. The system comprises a differential vacuum line switch, powered from the milking parlor vacuum line, and providing alternating vacuum pulses in a pair of vacuum lines; a liquid disinfectant pressure pump powered from the pair of vacuum lines; a pressure bottle for holding a volume of disinfectant under pressure and a spray line and spray head. The system is pressure self-limiting and has a pressure release valve operative when the milking parlor vacuum line is shut down.

Abstract: An electrically operated fuel pump device for use in vehicles comprises a regenerative pump component and an electric motor component operatively connected to the regenerative pump component to actuate the same. The regenerative pump component includes a casing defining therein a pump chamber and a closed vane type impeller rotatably disposed within the pump chamber. The impeller has an outer peripheral portion thereof cooperating with the pump chamber to define a pump flow passage. The impeller has in the outer peripheral portion a plurality of circumferentially spaced vane grooves formed in opposite end faces of the impeller. The impeller has its outer diameter within a range of approximately 20-65 mm. A flow passage representative dimension defined by S/l is within a range of approximately 0.4-2 mm where S is a cross-sectional area of the pump flow passage and l is a cross-sectional peripheral length of the outer peripheral portion of the impeller.

Abstract: A fuel injection pumping apparatus of the rotary distributor type has cam lobes of a special form in which following the crest of the cam lobe there is a first portion during which limited outward movement of the pumping plunger can take place to relieve pressure in the pipelines connecting the pump with the injection nozzles and this is followed by a second portion which causes slight inward movement is to close any cavities in the fuel contained within the passage of the apparatus.

Abstract: A hydraulic motor which varies its displacement in accordance with varying torque loads on its output shaft. The motor is biased to a low displacement, low torque, high speed mode, and changes to a high displacement, high torque, low speed mode when the torque load on its output shaft increases. The motor has eccentrically disposed gerotor gears that rotate and orbit relative to each other to expand and contract fluid chambers on opposite sides of a center line of eccentricity. The gerotor gears can change their orientation relative to each other in response to changes in the torque load on the output shaft, changed, in order to change the displacement of the motor.

Abstract: A drive shaft (26) of a gear type fuel pump (2) forms a driving interconnection between an engine gearbox (4) and a shaft (14) which carries the driving gear (10) of the fuel pump. The drive shaft has a slightly diverging lubricant supply passage (65) which receives lubricant from an oil jet (70) in the engine gearbox and directs the lubricant to the engaged splines (44, 46) at the inboard end of the drive shaft. Lubricant from the area of spline engagement is returned to the gearbox via radial passage (78), annular lubricant return passage (68) and radial passage (80). O-ring seals (82, 84) on the drive shaft, which straddle a drain passage (86) prevent the mixing of the lubricant and the fuel which may envelop an intermediate portion of the drive shaft. Wear of the engaged, oil lubricated splines (40, 42) at the outboard end of the drive shaft should provide a general indication of spline wear at the inboard end of the drive shaft because both ends are exposed to similar lubrication.

Abstract: In a refrigerant compressor for use in an air conditioning system, a lubricating oil-separating device is mounted in the discharge pressure chamber communicating with pump outlets of the pump assembly and also with the discharge port. The lubricating oil-separating device comprises a plurality of tubes vertically disposed in a direction traversing flows of compressed refrigerant. The tubes each have at least one recess formed in a portion of its peripheral surface facing downstream of the compressed refrigerant flow, and an opening formed in the recess and communicating with the interior of the tube, whereby compressed refrigerant in the form of von Karman's vortices formed immediately downstream of the tube is introduced into the interior of the tube to thereby effectively separate the lubricating oil from the refrigerant.

Abstract: The drive and driven gears of a pump are formed with grooves extending inward from the tips of the teeth to inside the root diameter. Thus each gear is divided into a first portion which serves solely as a drive or driven gear and a second portion which serves the two functions of a conventional pump gear, mainly to perform the pumping function and part of the drive function. Fitting within the grooves of both gears is a suction shoe which also overlies the inlet duct of the pump block and the mesh points of the first portions of the gears plus about two teeth to either side of the mesh point. The shoe separates the large portion of the pump chamber from the inlet duct.

Abstract: An auxiliary radially shifting mechanism for vanes in a pump of the vane type having a cup-shaped cylinder, a rotor eccentrically and rotatably received within the cylinder, a number of vanes radially shiftably disposed within said rotor, and a bracket closing the cylinder at its open end, is provided in the form of a ring-shaped projection formed on the bracket so as to protrude therefrom towards the side of the vanes and to surround the rotor, the outer edge of the projection being rounded.

Abstract: An apparatus is described for use in a urethane foam molding process to make a molded packing that is employed in the packaging of an article. A generally air tight housing is placed in cooperative relationship with a box in whose chamber the molded packing is to be made with one housing port located for air flow communication with the chamber and another housing port being located for air flow communication with ambient air. A pair of motor driven air blowers are mounted inside the housing with each air blower operatively positioned at a housing port. When one air blower is energized it causes the evacuation of air from the chamber of the box through one port to draw and hold a polyethylene sheet into the cavities of the chamber and of a mold form located therein. The air is exhausted past the other air blower and port. When the other air blower is energized, air flow through the ports is reversed so as to blow air into the box chamber for the release of the molded packing.

Abstract: A melt spinning apparatus is disclosed which is adapted for forming a plurality of synthetic filaments from a molten polymer. The apparatus comprises a spin block composed of a spin plate having a plurality of transverse ducts, a cover plate overlying the spin plate, and a cavity formed between the two plates and communicating with the ducts for receiving the molten polymer. A pair of side plates are disposed along respective opposite sides of the block, and the block and side plates include mating inclined contact surfaces whereby tightening of the side plates against the block causes the spin plate and cover plate to be pressed toward each other, whereby a seal is formed between the plates which prevents leakage of the molten plastic from the cavity.

Abstract: A modular spinnerette assembly for forming hollow fibers wherein a spinnerette plate having a central bore is positioned in stacked alignment with a cylindrical member having an enlarged central opening and an annular plate, with a tube extending radially through one side of the annular plate and terminating in the bore in the spinnerette plate for cooperating with this bore to form a hollow fiber when a spinning solution is passed through the apparatus. The assembly is provided with means for centering the tube in the central bore in the spinnerette plate.

Abstract: In the case of an apparatus for dewatering and plastifying water-wet mixts of materials for manufacturing explosives, as for example mixtures for producing propellent charges, using a screw extruder with one or more screws having kneading and conveying elements and a housing, possibly made up of axial sections, with a filling port for the said mixture as wetted with water, certain steps are taken for stopping the formation of slurries at the back end or part of the screw extruder, that is to say at the filling port there is an outwardly widening drain port with a drain duct joined thereto in which there is a conveyor for clearing the expressed water and the solids therein and moving them to the back end of the screw extruder.

Abstract: An elastomeric spring is formed by extruding a rubbery material into a reinforcing sleeve in a mold during relative motion between the mold and nozzle, and thereafter vulcanizing.

Abstract: An annular spacer to be used, during the vulcanization in a metal mold of an unvulcanized rubber hose having a mandrel pierced therethrough, as fitted around the mandrel in intimate contact with either of the opposite ends of the aforementioned unvulcanized rubber hose. This annular spacer has an outside diameter greater than the inside diameter of the depression in the aforementioned metal mold and an inside diameter enough for the spacer to be inserted around the aforementioned mandrel, contains in the periphery thereof a plurality of grooves formed in the axial direction of the spacer, and is made of a material softer than the materials of the aforementioned metal mold and mandrel. By the use of such spacers of this invention having the aforementioned characteristics, therefore, rubber hoses of a fixed outside diameter can be manufactured in any desired length in one and the same metal mold.

Abstract: Apparatus for moulding an article (11) of thermoplastic material from a parison (10) in which certain parts (17,16) of the parison are re-formed while other parts (13,12,20) retain their shape. A difference in pressure is applied to the wall of the parison during the re-forming process. Material in the parison is also moved in the direction of those parts of the parison which are to be re-formed, whereby attenuation of the material may be avoided entirely, if so desired, also in those parts which are to be re-formed. The invention enables the parison for a bottle to be re-formed to an extent which is small by comparison with the thickness of the material, for example the so-called "neck support" ring and the so-called "pilfer proof" ring, starting with a tube of oriented material. In a device for the application of the invention the elements (22,21,25) are in contact with the parts (13,12,20) of the parison.

Abstract: A kerosene heating stove is equipped with a temperature sensor and a carbonic oxide sensor. The temperature of a space is maintained at a constant level by automatically increasing and decreasing the burning length of a wick in the kerosene heating stove to change the height of the heating flame. The carbonic oxide sensor automatically generates an alarm and decreases the length of the wick to extinguish the flame if the concentration of carbonic oxide in the space increases to a predetermined dangerous level. In another embodiment, a kerosene heating stove is provided with a humidifier which automatically permits water to flow into an evaporating container in proximity to the flame when the moisture content of the air in the space falls below a predetermined level in order to regulate the moisture content of the air.

Abstract: A control device controls the air ratio in a combustion apparatus constructed so that combustion fuel supplied via a combustion fuel supplying pipe is burned with oxygen-enriched air obtained by drawing air through an oxygen permeable selective membrane by means of a vacuum pump provided at the downstream side of the oxygen permeable selective membrane and supplied via an air supplying pipe. The control device has an air flow meter and an oxygen concentration analyzer, both provided at the air supplying pipe, and a fuel flow meter provided at the combustion fuel supplying pipe. The air ratio is calculated from the values of the flow rate of of air, the oxygen concentration and flow rate of the combustion fuel. The amount of air drawn by the vacuum pump is controlled so that the actual air ratio is equal to an predetermined air ratio.

Abstract: A method and system for injecting coal and process fluids into a fluidized bed gasification reactor. Three concentric tubes extend vertically upward into the fluidized bed. Coal particulates in a transport gas are injected through an inner tube, and an oxygen rich mixture of oxygen and steam are injected through an inner annulus about the inner tube. A gaseous medium relatively lean in oxygen content, such as steam, is injected through an annulus surrounding the inner annulus.

Abstract: The invention relates to a method and apparatus for introducing a catalyst into a fuel mixture. The method includes placing water in a container; passing air through the water to ionize at least a portion of the air molecules wherein at least a major portion of the air ions have a negative charge; and introducing the ionized air into a fuel mixture. In this manner, the efficiency of the combustion of the fuel mixture is increased. The apparatus includes a container for holding water, a manifold mechanism for passing air through the water in the container in a number of streams of small bubbles and means for removing substantially all mist from the ionized air before the ionized air is removed from the container. Means are provided for removing the ionized air from the container after the air has passed through the water and for then introducing the ionized air into a fuel mixture.

Abstract: Burner for a concealed flare has a fuel gas supply pipe having a low resistance to upward aspirated air flow. The pipe has outlets directing fuel gas onto adjacent plates which cause spreading and mixing of fuel gas with aspirated air. The angle of fuel gas impingement on the plates is 1.degree. to 55.degree. and the plates have a flame retaining top edge.

Abstract: A modified carbon ink for a flash lamp array circuit containing a particulated electrically conductive material such as graphite or metal flakes, metal-coated glass spheres and the like. The increased electrical conductivity obtained in this manner improved flashability and electrostatic flash out protection for the associated flash lamps.

Abstract: A solvent reducing oven wherein stock that includes solvent is conveyed through an oven housing from which the solvent vapors are ducted and propelled into the side of the burner at an acute angle of about 60 degrees plus or minus 5 degrees to the burner axis. The solvent vapors are thereby combusted and the heated gases resulting being mixed with regulated quantities of air and propelled back into the oven for further solvent evaporation.

Abstract: A paint bake oven (10) including an outer insulated housing (12), the outer insulated housing having an inner wall surface (14). An inner housing (16) is disposed within the outer housing (12) and has an outer wall surface (18) spaced from the inner wall surface (14) to define a gas flow channel (20) therebetween. The inner housing (16) has an inner product passageway (22). A gas supply plenum (46) is disposed above the inner housings for supplying a gas flow to the gas flow channel (20). A gas exhaust passageway (38) exhausts gas from the product passageway (22). The oven (10) is characterized by including a manifold wall (28) for directing the gas flow along a flow path from the gas supply plenum (46) downwardly along the inner wall surface (20) of the outer housing (12) and then upwardly over the outer surface (18) of the inner housing (16) to uniformly distribute the gas flow over the inner housing (16).

Abstract: An orthodontic device comprises a face bow member which includes generally diverging outer arms adapted for connection to an orthodontic headpiece and inner arms extending between the outer arms and adapted to project into the mouth of the user. A stem member is rotationally connected with each of the inner arms and is biased toward a given rotational position. An annular collar adapted for engagement with a tooth is removably connected on each of the stem members so that rotation of each stem member is transmitted into arcuate movement of the associated collar. When the collars are engaged on the teeth, the stem members are each located out of their normally biased position, so that the biasing force serves to arcuately move the collar.

Abstract: A dental handpiece having therein a non-contact rotating speed detection device which includes an electromagnetic induction pulse generator including a permanent magnet provided close to the rotor in the head of a dental handpiece and a coil wound around the permanent magnet, and a rotor made of a magnetic material provided with recesses and/or projections around its circumference. The handpiece according to the invention facilitates to accurately detect rotor speed by detecting a pulse voltage proportionate to the rotation speed and therefore is useful for dental treatment and experiments.

Abstract: An improved device for measuring an inclination angle of the tapered surface of a plaster die duplicated from the prepared tooth in the field of restorative dentistry is disclosed. The device is used also for scraping operation for the was pattern. It includes a turnable tool holding plate which is turnably held in a slot formed on the lower part of a core so as to turn about a support shaft. A rotary ring with its lower end face cut to a predetermined inclination angle, for instance, 7 degrees is rotatably fitted onto the core in such a manner that the lower inclined face comes in contact with the upper faces of wing-shaped lateral projections of the tool holding plate with a transversely extending shaft disposed therebetween. The transversely extending shaft is inserted through the tool holding plate at the same inclination angle as that of the lower inclined end face of the rotary ring so that its axis intersects with the axis of the support shaft.

Abstract: A device for opening and closing a chuck for a dental handpiece has a handle portion and a powerhead assembly including a hollow driving shaft having, adjacent to its front end, a fowardly outwardly tapering portion joining a small diameter rear portion and a large diameter front portion. A hollow cylindrical chuck has a forwardly outwardly tapering outer peripheral surface joining a small diameter rear surface and a large diameter front surface corresponding to the respective driving shaft portions. The chuck is slidably inserted into the driving shaft. Three radial openings are formed at equally spaced positions in the forwardly outwardly tapering outer peripheral surface of the cylindrical chuck. A disc-shaped chucking die is slidably fitted into each radial opening to hold a dental tool. A chuck pusher is held in a socket with a disc plate spring interposed between the socket and the chuck pusher, and the pusher is movable for axially displacing the chuck to hold or release the dental tool.

Abstract: A device for connecting to the body of a dentistry counter-angle the unit for transmitting the rotary movement of the major axis of the counter-angle to the oblique shaft contained in the head of the counter-angle. The transmission assembly is placed inside a socket (5), forming a case, the socket itself being fixed to the body of the counter-angle by means of a bayonet attachment, consisting of at least one pin (16), fixed to the inner wall of the body of the counter-angle, and of at least one L-shaped slot (12), formed on the socket. Application to the rapid assembling and dismantling of dentistry equipment.

Abstract: A beam position processor (15) generates address signals representing the spatial coordinates of points on a simulated radar beam, for a plurality of beam directions. The address signals serve for readout of weather information (e.g. cloud intensity, ceiling and base height data) from a data storage means (16) for further processing to form a video signal for display. The storage means (16) is arranged for economy of memory capacity in that the higher order parts of the address are used to read out code words from a database memory (17). Each code word selects one of a set of predetermined cloud patterns in cloud pattern memories (18, 19) and the lower order parts of the address access data corresponding to individual cells of the selected pattern.

Abstract: A rotatable globe has a drive motor supported by a stationary shaft, the drive motor being positioned entirely within the globe and having switching means actuated by manual rotation of the globe.

Abstract: A globe of inflated envelope is supported by a bowed arm formed of releasably connectible curved segments and detachably mounted on a stand. The bowed arm further carries a casing containing a driving mechanism for rotating the globe and producing a musical sound during rotation of the globe.

Abstract: A fold-out garment book in which a book unfolds to a costume. The book includes a sheet folded to define a plurality of panels which form pages of the book. The pages include printing thereon in a predetermined sequence to present a story. The sheet is unfolded as the pages are viewed in sequence with the unfolded sheet including an opening therein to permit wearing of the sheet as a costume. The panels presented when the sheet is worn in unfolded condition include printing thereon to define the costume.

Abstract: A statistical teaching apparatus includes a plurality of parallel circuits selectively coupled to an operational amplifier. Each circuit is adapted to receive a component from a population being statistically evaluated. The circuits include amplifier feedback elements arranged to selectively cause the amplifier to produce an output voltage representing the value of a parameter of any selected component or the average parameter value of any selected group of components so as to permit plotting of actual parameter values of a selected subgroup and measuring the average parameter value of that subgroup.

Abstract: An apparatus and method for teaching a person inspirational phrases. The method comprises a visual display of an inspirational symbol which imparts a sensation of movement towards the person via a steady increase in overall dimension. When the inspirational symbol had attained maximum dimension the words of an inspirational phrase are illuminated below. Simultaneously, an audio track reads aloud the displayed inspirational phrase. The apparatus comprises: shutters which pivotally open and slide into a housing revealing an exhibiting area for showing an inspirational symbol; a display area for exhibiting inspirational phrases; an audio system to broadcast the displayed inspirational verses; and an operating system for changing the displayed inspirational verses in conjunction with the audio system.

Abstract: An ultrasound phantom is provided which simulates human tissue containing tissue masses viable for biopsy. The phantom is used to demonstrate or teach the performance of a biopsy procedure assisted by real-time ultrasonic imaging. The phantom comprises a plurality of small balloons, filled with a viscous substance, and tied shut. The balloons are distributed through and surrounded by a gelatinous substance comprising tissue equivalent material. During a simulated biopsy procedure, a section of the phantom is imaged as a biopsy needle penetrates through the tissue equivalent material, pierces one of the balloons, and aspirates some of the viscous substance from the balloon.

Abstract: This invention relates to an educational device having a card with notched edges and a series of numbers or words along each longitudinal edge of the card corresponding to each notch. The correct answer to a problem from one edge of the card, whether arithmetic or grammatical or historical, is found on the opposite edge of the card. A string member is used to connect the problem on one edge of the card with the correct answer on the other edge. The reverse side of the card has the correct string lines imprinted thereon corresponding to the correct placement of the string member for the correct answers to the problems on the face side of the card.

Abstract: A radio-controlled teaching device comprising a teacher transmitter unit and a plurality of student receiver units for maintaining student alertness during oral reading of written textual material, for the oral administration of multiple-choice or true or false test material, and for the preparation and presentation of recorded programmed instructional material. The teacher transmitter unit contains a tone generator and radio transmitter which transmits discrete tone signals, either under manual control of the teacher or automatically under the control of a plural channel instructional tape recording. Each student receiver unit contains timers, a logic circuit, and a radio receiver which receives the above tone signals (which are transparent to the students) and provides a short time period during which the student is expected to respond by briefly closing a response switch. The short time periods correspond to portions of a text being orally read, such as the end of a paragraph, proper nouns, verbs, etc.

Abstract: A position sensing unit for the outboard drive of a marine engine for providing an indication of the trim angle of the drive. The position sensing unit comprises a sensing device that is carried by the outboard drive outboard of the transom and an angle reading device that is positioned inboard of the transom. A connecting device transmits a position signal from the sensing device to the angle reading device so that the angle reading device may be positioned remotely from the outboard drive.

Abstract: A conventional bicycle has its frame rigidly supported by a base framework held by adjustable length outrigger arms, whose outer ends are connected with bearings mounted on two spaced floats. The rear bicycle traction wheel frictionally engages and drives a propulsion wheel connected through gearing with a propeller. A tubular arm pivoted at its forward end to the base framework extends rearwardly beneath the bicycle traction wheel and supports the propulsion wheel, gearing and propeller. A pivoted rudder on the rear end of tubular arm is operated by cables extending through such arm and leading to the axle of the front steering wheel of the bicycle. The device possesses windsurfing and rowing capabilities.