Abstract: A sound attenuation canopy for reducing levels of sound passing through an opening comprises a sound absorbing member. The member is comprised of a flexible sound absorbing material and has a first end, a second end and an intermediate portion extending therebetween. The first end is configured to attach to the opening's periphery at a first location, the second end is configured to attach to the periphery at a second location and the intermediate portion is configured to be spaced apart from the opening. When the first end and the second end are attached to the periphery of the opening, at least one side opening is at least partially defined by the intermediate portion and the perimeter of the opening, and a sound transmission flow path through open space between the opening and the side opening comprises at least one change of direction greater than 45 degrees.

Abstract: A sound attenuation canopy for reducing levels of sound passing through an opening comprises a sound absorbing member. The member is comprised of a flexible sound absorbing material and has a first end, a second end and an intermediate portion extending therebetween. The first end is configured to attach to the opening's periphery at a first location, the second end is configured to attach to the periphery at a second location and the intermediate portion is configured to be spaced apart from the opening. When the first end and the second end are attached to the periphery of the opening, at least one side opening is at least partially defined by the intermediate portion and the perimeter of the opening, and a sound transmission flow path through open space between the opening and the side opening comprises at least one change of direction greater than 45 degrees.

Abstract: A sound attenuation canopy for reducing levels of sound passing through an opening comprises a sound absorbing member. The sound absorbing member is comprised of a flexible sound absorbing material and has a first end, a second end and an intermediate portion extending between the first end and the second end. The first end is configured to attach to a periphery of the opening at a first location, the second end is configured to attach to a periphery of the opening at a second location and the intermediate portion is configured to be spaced apart from the opening. When the first end and the second end of the sound absorbing member are attached to the periphery of the opening, at least one side opening is at least partially defined by the intermediate portion and the perimeter of the opening, and a sound transmission flow path through open space between the opening and the side opening comprises at least one change of direction greater than 45 degrees.

Abstract: A sound attenuation canopy for reducing levels of sound passing through an opening comprises a sound absorbing member. The sound absorbing member is comprised of a flexible sound absorbing material and has a first end, a second end and an intermediate portion extending between the first end and the second end. The first end is configured to attach to a periphery of the opening at a first location, the second end is configured to attach to a periphery of the opening at a second location and the intermediate portion is configured to be spaced apart from the opening. When the first end and the second end of the sound absorbing member are attached to the periphery of the opening, at least one side opening is at least partially defined by the intermediate portion and the perimeter of the opening, and a sound transmission flow path through open space between the opening and the side opening comprises at least one change of direction greater than 45 degrees.

Abstract: A control system for a powered wheel chair drive modulates a pulse power delivery signal such that power is delivered gradually at throttle positions corresponding to a low speed, and power is delivered more rapidly at throttle positions corresponding to a higher speed.

Abstract: A wheel chair drive apparatus includes a frame having a wheel mount, a battery mount, and a control shaft mount. A drive wheel has a drive motor incorporated within the drive wheel. A battery is in operative communication with the drive motor via a detachable jack. A battery housing is dimensioned to mount in the battery mount of the frame and has a handle. A control shaft pivotably mounted on the control shaft mount, so that it has a stow position, and operating position, a user entry position and a table use position. A caster lever is pivotably mounted to the frame, so that it has a rolling position and an engaged position. The caster lever is disposed to engage a receiving seat on a wheel chair. A locking lever is releasably biased toward a position locking the caster lever in the engaged position.

Abstract: A boom conveyor including a cantilevered conveyor section having an operator's platform at its outer free end is disclosed. The conveyor section is mounted so that in use the outer free end is movable in a vertical plane between predetermined limits. A scissor support is disposed at or adjacent the outer free end and is passively extended by the raising of the free end of the conveyor to provide continual support to the platform. A release valve enables retraction of the support when the free end is lowered.

Abstract: A seed planter monitor is used with a traveling seed planter operable to periodically dispense seeds in each of a plurality of rows. The monitor, preferably a microcomputer device, comprises individual row counters for counting the seeds planted in each row. The monitor determines the row having the highest deviation from the average number of seeds planted per row. Whenever the maximum deviation exceeds a predetermined limit, an alarm signals an error condition to the planter operator. The monitor also senses and warns the operator of any stoppage occurring in any of the rows within a relatively short stoppage distance. Planting data is displayed to the operator during planting.

Abstract: A fully automatic microcomputer-controlled tape cartridge handling system. As illustrated here, it has a high degree of redundancy providing maximum reliability in radio broadcasting service and other applications. It comprises two storage drums, four stacks of playback transducers, two cartridge transfer mechanisms, a loading chute, and an unloading chute. Each drum has a cylindrical configuration with 512 cartridge storage compartments arranged in 16 vertical columns around its circumference and 32 horizontal rows along its axis. Two transducer stacks and one transfer mechanism are on each side of the pair of drums. Each transfer mechanism is positioned adjacent both drums and positioned adjacent two of the transducer stacks, one of the transfer mechanisms also being adjacent the loading and unloading chutes. Each transfer mechanism has a cage which is selectively rotatably swingable to positions aligned with either drum or either adjacent transducer.

Abstract: A combined eraser and splice finder for an NAB tape cartridge which comprises apparatus for subjecting an NAB tape cartridge to an initially strong and thereafter diminishing and vanishing oscillating magnetic field for bulk tape erasure and which, independently or at the termination of the erasure cycle, also senses the presence of the tape splice and stops tape travel within the cartridge at a point where subsequent recording can begin immediately behind the splice. The apparatus is capable of erasure without splice-finding or splice-finding without erasure.

Abstract: A dual capstan tape transport mechanism having a magnetic tape trained along a path for movement successively between an upstream capstan and pressure roller, past record and play heads, and between a downstream capstan and pressure roller. A motor drives the downstream capstan directly and drives the upstream capstan indirectly, and slightly slower, through an overrunning clutch. Separate solenoids move the pressure rollers to press the tape against the respective capstans. The mechanism is selectible to play either an improved dual capstan type cartridge with both capstans, or to play a conventional single capstan type cartridge with the downstream capstan alone. Tape guide posts, aligning the tape and providing wrap around the heads, and a shield engageable with the backside of the tape opposite the play head, are movable with the upstream pressure roller through openings in the housing of the dual capstan cartridge.

Abstract: A fully manually adjustable embodiment has a base member fastened to and spaced from a tape deck frame. Two identical mounting block members are provided, one for a recording head and one for a reproducing head. A rear portion of each mounting block member is positioned in the space between the base member and the tape deck frame. Three balls, loosely retained in cylindrical bores in the bottom face of the base member, are seated in spherical recesses in the top face of each mounting block member. An adjusting screw, threadedly engaged with the base member, extends into each cylindrical bore, engaging the corresponding ball. Tension springs are connected between pins in the base member and each mounting block member to draw them toward one another and thereby engage the balls between the adjusting screws and the spherical recesses. Two of the balls on each mounting block member are located along a central axis of the head to establish an azimuth axis.

Abstract: A dual capstan tape transport mechanism having a magnetic tape trained along a path for movement successively between an upstream capstan and pressure roller, past record and play heads, and between a downstream capstan and pressure roller. A motor drives the downstream capstan directly and drives the upstream capstan indirectly, and slightly slower, through an overrunning clutch. Separate solenoids move the pressure rollers to press the tape against the respective capstans. The mechanism is selectible to play either an improved dual capstan type cartridge with both capstans, or to play a conventional single capstan type cartridge with the downstream capstan alone. Tape guide posts, aligning the tape and providing wrap around the heads, and a shield engageable with the backside of the tape opposite the play head, are movable with the upstream pressure roller through openings in the housing of the dual capstan cartridge.

Abstract: A combined eraser and splice finder for an NAB tape cartridge which comprises apparatus for subjecting an NAB tape cartridge to an initially strong and thereafter diminishing and vanishing oscillating magnetic field for bulk tape erasure and which, independently or at the termination of the erasure cycle, also senses the presence of the tape splice and stops tape travel within the cartridge at a point where subsequent recording can begin immediately behind the splice. The apparatus is capable of erasure without splice-finding or splice-finding without erasure.

Abstract: Reproducing apparatus for magnetic tape in which the forward and rewind torques motors are series-interconnected to moderate their torques and limit the tape tension during play mode only, thereby eliminating the large heat-generating resistors required when the torque motors are parallel-connected by the conventional arrangement. Relatively small variable resistor means is provided in the power supply to the series-interconnected torque motors, enabling adjustment of tape tension in the play mode. In the specific embodiment illustrated, the variable resistor means comprises two individual resistors. Switch means selectively connects one or both resistors into the torque motor power supply circuit to keep tape tension within a predetermined range during play mode for different size tape reels.

Abstract: Automatic azimuth control for a multi-track magnetic tape recorder-reproducer. This is illustrated as stereo apparatus having a recording head with right and left recording gaps through which signals are recorded respectively on right and left tracks on the tape, and a reproducing head with right and left reproducing gaps through which the signals on the right and left tracks are reproduced. An azimuth control circuit simultaneously starts the tape drive and actuates a tone generator to record test signals in phase on the tape tracks. The test signal reproductions from the respective right and left gaps of the reproducing head are fed to a phase comparator which senses their time relationship. An azimuth motor, responsive to this time relationship skews one of the heads relative to the tape in a direction to bring the test signal reproductions into phase with one another. When they are brought into phase, the azimuth control circuit is automatically deactuated and the tape drive is stopped.

Abstract: A dual capstan tape transport mechanism having a magnetic tape trained along a path for movement successively between an upstream capstan and pressure roller, past record and play heads, and between a downstream capstan and pressure roller. A motor drives the downstream capstan directly and drives the upstream capstan indirectly, and slightly slower, through an overrunning clutch. Separate solenoids move the pressure rollers to press the tape against the respective capstans. The mechanism is selectible to play either an improved dual capstan type cartridge with both capstans, or to play a conventional single capstan type cartridge with the downstream capstan alone. Tape guide posts, aligning the tape and providing wrap around the heads, and a shield engageable with the backside of the tape opposite the play head, are movable with the upstream pressure roller through openings in the housing of the dual capstan cartridge.

Abstract: Solenoid has a coil which when energized moves a plunger inwardly through an opening in the housing against an external biasing spring which moves the plunger outwardly when the coil is deenergized. The front end wall of the housing has a plurality of bores disposed radially to the axis of movement of the plunger, each having a ferrous guide sleeve with an open end adjacent the plunger and a loose magnetic steel ball which is freely movable therein toward the plunger when the coil is energized. The plunger has an external groove within which the balls are seated when the plunger is in a fully retracted position. This enables the balls to extend from the open inner ends of the guide sleeves into latching positions holding the solenoid against outward movement. A much smaller electric power input is required in the coil to hold the balls in latched position, and therefore hold the plunger in retracted position, than is required to move the plunger to that position in the first place.