Abstract: A switching power supply for converting an input voltage to a different output voltage includes a power switch for producing a sequence of pulses from the input voltage, an output filter for filtering said pulses and for producing an output voltage from the filtered pulses, and means for sensing the output voltage and for controlling the value of the output voltage to a specified value. The power supply includes means for responding to a reduction in the input voltage beneath a normal value and for increasing the duty cycle of the sequence of pulses from the power switch in response thereto. Structure is provided for automatically controlling the frequency of the sequence of pulses to a selected value and for overriding the automatic control of this frequency so as to decrease this frequency in the event the load connected to the power supply draws too much current. Circuitry is provided to minimize off time in each period of the pulse sequence under "brown-out" conditions.

Abstract: A convertible furniture unit includes a tip-up bed (11) whose frame (12) is movable from a horizontal to a vertical position in a wall unit (10) around a torsion bar pivot (20). Connected to the frame (12) is an auxiliary furniture piece (30) such as a table (32) or sofa which is kept horizontal by a parallelogram linkage. As the bed unit (11) is moved from the vertical to horizontal position pivot point (34) attached to the bed frame moves forwardly and downwardly collapsing legs (37,38) with respect to fixed leg (35) and moving legs (37,38) outwardly from its point of connection with pivot connector (50). The table then nests under the bed when the bed is in the "down" position. The pivot connector (50) includes a floor connector (51), a U-shaped post member (57-59) and a hook member (55) which holds the post member on the floor connection.

Abstract: A dynamic RAM memory cell comprises an MOS read transistor whose conductivity state is determined by the state of charge on a first electrode overlying the read transistor channel region. The first electrode is connected through a buried contact opening to a diffused region in the substrate. This diffusion serves as a junction isolated storage node. This storage node can be charged or discharged through an MOS write transistor. The first electrode is capacitively coupled to a field plate held at a field potential. A control gate formed in a second electrode controls conduction through the write transistor and also allows selective reading in an array of read transistors. Nondestructive read can be achieved together with transistor amplification of the charge stored on the first electrode.

Abstract: A plasma generator includes a cap (20) having a sintered porous aluminium cuttings diffusor disc (28) spaced from the underside of a horizontal apertured top of the cap to prevent arcing therebetween and formation of a plasma plume affecting the wafer being etched. A plasma zone of reactive gases is formed between the cap and the wafer by rf energy. Process gases are conducted through cap top apertures (26) to the zone and the resultant plasma etches the semiconductor wafer spaced in parallelism from the cap top. Arcing between the metal diffusor and the metal cap is prevented by a ledge (27) on the cap interior periphery forming a gap between the bottom surface of the cap top and top surface of the diffusor. Etching or sputtering of the cap is also prevented by increasing the surface area of the apertures in the cap top to prevent ions from gaining a level of kinetic energy greater than the sputter threshold energy.

Abstract: A linear motion rolling contact bearing assembly includes a U-shaped rail of thin steel plate, a U-shaped table of thin steel plate which straddles the rail, a plurality of rolling members interposed between the rail and the table and a retainer for retaining the rolling members in position. Each side wall of the rail is provided with a curved section having oppositely extending slopes on which a pair of upper and lower inner guide surfaces are defined. Each side wall of the table is also provided with a curved surface having a pair of upper and lower outer guide surfaces which are located opposite to the pair of inner guide surfaces of the rail. A first plurality of rolling members are provided as interposed between the upper inner and outer guide surfaces and a second plurality of rolling members are provided as interposed between the lower inner and outer guide surfaces.

Abstract: A linear motion ball bearing structure provided between a slider and a straight track rail for allowing the slider to move along a straight line of movement defined by the track rail is provided. The present linear motion ball bearing structure includes an endless travelling path in the slider and which includes a load path section, a return path section and a pair of connection path sections each connecting the corresponding ends of the load and return path sections, thereby defining a closed loop. Thus, the balls provided in the endless path roll from the load path section into the return path section through one of the connection path sections and then back into the load path section through the other of the connection path sections as the slider moves along the rail in one direction.

Abstract: Each of a plurality of parallel connected power supplies is controlled by a parallel control circuit which measures the output current from each power supply and compares this output current to the average output current produced by all the power supplies and generates a signal representative of the difference therebetween to drive the output current of the power supply toward the average output current from all power supplies. The structure includes in addition a switch for disconnecting the parallel control circuit of a failed power supply from the system and a booster resistor for assisting in bootstrapping the startup of a given power supply being inserted into parallel with the preexisting parallel connected power supplies.

Abstract: A unique programming circuit, suitable for use with programmable read-only memories (PROM), or other circuits utilizing programmable fuses, is provided which overcomes several distinct disadvantages of prior art programming circuits. The programming circuit of this invention includes a Darlington pair of programming transistors which allows only a single programming transistor to be made large in order to carry the large programming current, and only a single high current drive signal need be applied to the single programming transistor, thereby minimizing power consumption and integrated circuit die area.

Abstract: A gyroscope constructed in accordance with the present invention includes a flywheel (220) which can oscillate with at least two degrees of freedom about a central position in which the flywheel axis is aligned with the axis of a drive shaft (200), the flywheel being held radially and rotated relative to the body (100) of the apparatus. The gyroscope also includes a set of electrodes (101 to 104) for electrostatically controlling the position or for detecting the position of the flywheel. The electrodes are fixed relative to the body and face corresponding conducting surfaces of the flywheel. In accordance with the invention, the gyroscope further includes a rigid spinning casing (250) which encloses the flywheel in such a manner as to interpose a dielectric surface between the corresponding conducting surfaces of the flywheel and each electrode, the casing being fixed to the flywheel drive shaft but not having any degrees of freedom in oscillation relative to the body other than being free to spin.

Abstract: A method of manufacturing a mask for use in x-ray photolithography includes the steps of coating a set of wafers (20) with boron nitride (22). The tension in the boron nitride is measured by using a capacitive probe (26) to measure bowing in a set of test wafers. The remaining wafers are attached to a pyrex ring (28), and the boron nitride is removed from one side of the wafers. A circular hole is then eteched in the wafer, and a layer of tantalum (32) and gold (34) are formed on the remaining boron nitride membrane. The gold (34) is patterned via a sputter etching process. Power is reduced at the end of the sputter etching process slowly to reduce mechanical stress in the mask. The tantalum (32) is then etched via a reactive ion etching process. In this way, an x-ray transparent boron nitride membrane is used to support x-ray opaque gold.

Abstract: A cross roller bearing includes an inner ring, an outer ring and a plurality of generally cylindrically shaped rollers placed in a channel defined between the inner and outer rings as being alternately crossed with any two adjacent rollers having their axes of rotation directed perpendicular to each other. Both of the inner and outer rings are unitary in structure. In one form of the invention, the outer ring is provided with a radial hole extending therethrough radially, through which the rollers may be inserted in the channel defined between the inner and outer rings. An insert is also provided to be fixedly fitted into the radial hole so as to close the radial hole after insertion of the rollers into the channel.

Abstract: An inverter (100) receives a DC voltage and generates therefrom a square wave output signal. The inverter includes an output transformer (T3) and a saturable core transformer (T4). The saturable core transformer (T4) provides base current for a first transistor (Q3) and a second transistor (Q4). The first transistor (Q3) and the second transistor (Q4) alternatively turn on and off, causing a square wave to appear across the secondary winding of the output transformer (T3). The primary winding of the output transformer is coupled to the collectors of the first and second transistors via a pair of windings (L10, L11) magnetically coupled to the saturable transformer (T4). A pair of diodes (D4, D5) are provided to prevent the output leads of primary windings of the output transformer (T3) from dropping below ground potential.

Abstract: An adjustable torsion bar assembly (10) includes a torsion bar frame (9) having upstanding legs (17, 18) and a structural frame (22) for holding a tip-up bed (11). A pair of torsion rods (20, 21) extend between a frame leg and a structural frame side. A lead screw (31) having threaded portions (32, 33) threaded in opposed helices extends between the structural frame sides which upon rotation moves a pair of pivot plates (35, 36) either inwardly or outwardly in unison. Each pivot plate includes a torsion rod-confining aperture (53, 54) in sliding engagement with a portion of a torsion span of rods as rotation of the lead screw adjusts the movement of the pivot plates along the rods changing the effective span of the torsion rods.

Abstract: A series biasing arrangement for a pair of junction field effect transistors (JFETs), which may be used in RF amplifiers, mixers or oscillators, comprises connecting the JFETs together in series, with the gates of the two JFETs selectively connected to different reference potentials. The first FET is also connected to the DC voltage source. In one embodiment of the invention, two operational amplifiers, whose output leads are connected to the gates of corresponding JFETs have their noninverting input leads connected to selected points on a voltage divider made up of three resistors and their inverting input leads each connected to the source of a corresponding JFET. The drain to source voltage drops across the JFETs are controlled solely by the values of two of the resistors in the three resistor voltage divider. The bias current through the series-connected JFETs can be controlled independently of the drain to source voltage drops across each of the JFETs. The two FETs need not be closely matched.

Abstract: A unique frequency doubler circuit is utilized which requires only a handful of standard components such as operational amplifier, logic gates, resistors, capacitors and switches. In contrast to certain prior art frequency doublers, frequency doublers constructed in accordance with the teachings of this invention do not require the use of a phase lock loop, thereby resulting in a substantial simplification of circuit construction. Furthermore, frequency doublers constructed in accordance with this invention utilize a feedback technique which assures that the duty cycle of the output signal will be 50%, or any other predefined value.

Abstract: Test circuitry is included in a PROM memory for detecting shorts between bit lines and word lines and shorts or leaks in a memory cell. The circuitry enables a selected positive voltage to be applied across all memory cells in the memory so that the existance of leaky memory cells or shorts in the memory can be detected during testing. The test circuitry has no appreciable effect on the memory during normal operation of the memory.

Abstract: A high-voltage bi-directional analog switch is implemented using a pair of MOS depletion type transistors having their sources connected together and having their gates connected together. The drains constitute the high voltage input port and the high voltage output port. The switch conducts so long as the voltage on the common gate connection relative to the voltage on the common source connection is more positive that the pinch-off voltage. The source-to-gate voltages are controlled by a means including an enhancement mode transistor. Voltage level shift means are provided to shift low level logic signals to a sufficiently high level to control conductance through said enhancement mode transistor. The source of voltage rails need not provide two high voltages but at most only a single high voltage level is required.

Abstract: A carrier is provided to hold a disk while magnetic material is plated simultaneously on the two surfaces of the disk. The carrier contains a first opening substantially the same diameter as the disk and a second opening formed about a center line offset from the center line of the first opening so as to form a recess around a portion of the edge of the first opening. The recess allows the disk to be mounted into the carrier by placing the disk in a portion of the first opening and in a portion of the recess without having a surface of the disk touch the surface of the recess. The disk is then lowered into the first opening while leaving the remainder of the carrier material adjacent the recess to block the flow of plasma and impurities from one side of the disk to the other during the coating of the surfaces of the disk with magnetic media. A plug is provided for placement in the center hole of the disk.

Abstract: An integrated circuit digital to analog converter comprised of MOS current mirrors and utilizing additional MOS devices to provide transmission gates and control means. Each transmission gate 36 is connected to a source of digital data to be converted and the mirroring device for each transmission gate 36 has a channel width with some predetermined proportional relationship to the channels of input transistors 12 and mirroring output MOS transistors 14 to 44 with the input transistor 12 connected to a constant current source, the total output mirroring current of the output mirroring transistors is in quantised analog form and varies according to the cumulative currents from the mirroring MOS transistors as the transistors are activated. The invention may be embodied in linear multiplying, non-linear and companding converters.