The invention relates to a nuclear fuel cladding totally or partially made of a composite material with a ceramic matrix containing silicon carbide (SiC) fibers as a matrix reinforcement and an interphase layer provided between the matrix and the fibers, the matrix including silicon carbide as well as at least one of the following additional carbides: titanium carbide (TiC), zirconium carbide (Zrc), and ternary titanium silicon carbide (Ti3SiC2). When irradiated and at temperatures of between 800° C. and 1200° C., said cladding can mechanically maintain the nuclear fuel within the cladding while enabling optimal thermal-energy transfer towards the coolant. The invention also relates to a method for making the nuclear fuel cladding.

A method for scanning and decoding encoded symbols comprises processing low resolution image data from a full field of view and/or high resolution image data from one or more windowed segments of the field of view to provide imaging that is easily adaptable to different types of symbols and varying environmental conditions. The scanning method can be switched between the low resolution mode and the high resolution mode automatically based on whether the low resolution data is sufficiently accurate to decode the symbol.

System and method for testing a high speed data path without generating a high speed bit clock, includes selecting a first high speed data path from a plurality of data paths for testing. Coherent clock data patterns are driven on one or more of remaining data paths of the plurality of data paths, wherein the coherent clock data patterns are in coherence with a low speed base clock. The first high speed data path is sampled by the coherent clock data patterns to generate a sampled first high speed data path, which is then tested at a speed of the low speed base clock.

A machine permits an end of a thick-walled, high-pressure tubing to be chucked in a collet one time, coned, faced and threaded, using a coning head and threading head which are mounted on a carriage which can be translated laterally between three positions and the coning and threading heads parallel to the longitudinal axis of the workpiece to complete the coning and threading operations.

In a high-voltage apparatus according to this invention, a predetermined voltage is applied to a rotating anode after waiting until the number of rotations increases to such an extent that the rotating anode is not damaged. That is, X-rays of desired intensity are already outputted from a point of time when the voltage is applied to the rotating anode. Therefore, diagnosis can be performed immediately after the voltage is applied to the rotating anode. That is, unlike the prior art, there is no need to wait until X-ray intensity becomes suitable for diagnosis after X-ray emission is started, and there is no need to irradiate the patient with unnecessary X-rays. Therefore, the patient can be inhibited from being irradiated with excessive X-rays (with an improvement made in a response from when the operator gives instructions for starting fluoroscopy until emission of X-rays suitable for diagnosis).

A surfactant film viewing apparatus having a chassis, film wand, and film wand positioning means. The chassis is opaque and has a magnifying lens and a light aperture to allow ambient light into the interior of the chassis. The chassis, with the exception of the light aperture and the magnifying lens, forms an substantially closed surface. The film wand has a hoop suitable for supporting a surfactant film across its span. The apparatus includes a means for positioning of said hoop in said interior of said chassis such that the position of said hoop relative to the magnifying lens is stable but manually adjustable so the surfactant film can be positioned for viewing by said magnifying lens. The apparatus may include a reservoir for the surfactant/water mixture, and the means for positioning may also include a means for dipping the hoop in the surfactant/water mixture. In an alternate embodiment the wand has multiple hoops each of which is capable of supporting a surfactant film, rotation of the wand bringing the surfactant films sequentially into view.

There is provided a high frequency switch having a reduced circuit scale while maintaining satisfactory harmonic characteristics in a transfer path of a high frequency signal. The high frequency switch includes: at least one transmission port; at least one reception port; a common port; transmission side series switches each including a body contact type FET; transmission side shunt switches each including a body contact type FET; reception side series switches each including a body contact type FET; and reception side shunt switches each including at least one floating body type FET.

An attenuation reduction control structure for high-frequency signal transmission lines of a flexible circuit board includes an impedance control layer formed on a surface of a substrate. The impedance control layer includes an attenuation reduction pattern that is arranged in an extension direction of the high-frequency signal transmission lines of the substrate and corresponds to bottom angle structures of the high-frequency signal transmission lines in order to improve attenuation of a high-frequency signal transmitted through the high-frequency signal transmission lines. An opposite surface of the substrate includes a conductive shielding layer formed thereon. The conductive shielding layer is formed with an attenuation reduction pattern corresponding to top angle structures of the high-frequency signal transmission lines.

An electronic component includes: a first circuit connected to a first common terminal for inputting/outputting a first signal set, a second common terminal for inputting/outputting a second signal set having a frequency higher than the first signal set, and a third common terminal for being connected to an antenna; and a second circuit connected in parallel to the first circuit between the first and second common terminals, wherein the first circuit includes a first filter transmitting the first signal set and reflecting the second signal set, and a second filter transmitting the second signal set and reflecting the first signal set, the third common terminal is located between the first and second filters, and the second circuit reflects a first transmission signal and a second transmission signal, transmits parts of the first and second transmission signals, and inverts phases of the parts of the first and second transmission signals.

Guard elements (31) are provided for the corner connectors (16 through 19) of a heald shaft (10) of a shedding unit, the guard elements covering the open space formed between the two legs (26, 27) and thus providing a grip protection.

An anti-“Methicillin-Resistant Staphylococcus Aureus (MRSA)” chitosan containing antibacterial High Wet Modulus (HWM) rayon fiber textile for medical usage is made of the steps as following: chitin flakes made from natural shrimp or crab shells are deacetylated to generate chitosan with a high deacetylation degree of 90% or more. Next chitosan is dissolved in acetic acid and regenerated by caustic soda to form a chitosan antibacterial nanoparticles slurry, then added to HWM viscose rayon process, and spinning to produce a chitosan containing antibacterial HWM rayon fiber. The antibacterial amino groups of chitosan and the hydroxyl groups of rayon cellulose combine together via hydrogen bonding. Therefore, the fiber becomes the anti-MRSA antibacterial HWM rayon fiber containing amino groups (—NH3+). Finally the resulting HWM rayon fiber is conducted via a yarn spinning or/and weaving process to procure a medical textile with chitosan content.

Processes for the production of high strength polyethylene tape articles from high strength ultra-high molecular weight multi-filament yarns, and to the tape articles, fabrics, laminates and impact resistant materials made therefrom.

The efficiencies of illustrative embodiments of vertical center flue type fuel-fired base water heaters are improved by installing in the water heaters variously configured tubular condensing type secondary heat exchangers of smaller diameters than the associated center flues. The efficiency increases are achieved with components and manufacturing processes similar to those utilized in the base water heaters and secondary heat exchanger materials similar to those in the tank portions of the base water heaters.

A DC voltage converter includes an oscillator that converts a DC battery voltage to an oscillating voltage, a low voltage transformer that increases the oscillating voltage to a higher oscillating voltage, and a voltage rectifying-capacitor charging network or multiplier that increases the higher oscillating voltage to yet a higher DC voltage at an output terminal for DC high voltage utilization devices and the like. An electric control switch is selectively actuated by the user to apply the battery voltage to the oscillator, resulting in the generation of the stepped-up DC voltage at an output terminal. Another DC voltage converter has an electronic switching circuit that automatically turns the oscillator on and off and a load capacitor across the electrodes that is charged and discharged to provide a shocking voltage. Utilization devices for the voltage developed by the converter shown are a miniature animal training device and a cattle prod device. The miniature animal training device has a pair of outwardly projecting electrodes mounted on a side at one end of the housing that is sized and shaped to fit within and conform to the palm of a hand. The cattle prod device has a pair of electrodes fixedly mounted on the end of a housing assembly made up of telescoping tubular housing sections arranged for relative axial movement whereby the pressing of the electrodes against an object to be shocked actuates the electric control switch and causes a shock of the object. The housing assembly is releasably supported by a rigid handle or an extensible handle assembly.

A system for storing, rotating and feeding a high pressure hose. A first portion of the hose is disposable about the drum and a guide arm engages a second portion of the hose. An actuator assembly rotates a cage and the guide arm so that the guide arm rotates relative to the cage such that the hose is rotated. Relative rotation in one direction causes the first portion of the hose to uncoil from the drum and displace along the guide arm and causes a third portion of the high pressure hose in an output port to displace out of the output port away from the guide arm. Relative rotation in an opposite direction causes the second portion of the high pressure hose to coil about the drum and causes the third portion of the high pressure hose to displace into the housing.

A hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed that includes a mildly etched seed layer and a hard bias (HB) layer on the etched seed layer. The HB layer may contain one or more HB sub-layers stacked on a lower sub-layer which contacts the etched seed layer. Each HB sub-layer is mildly etched before depositing another HB sub-layer thereon. The etch may be performed in an IBD chamber and creates a higher concentration of nucleation sites on the etched surface thereby promoting a smaller HB average grain size than would be realized with no etch treatments. A smaller HB average grain size is responsible for increasing Hcr in a CoPt HB layer to as high as 2500 to 3000 Oe. Higher Hcr is achieved without changing the seed layer or HB material and without changing the thickness of the aforementioned layers.

A method for producing a transparent and conductive metal oxide layer on a substrate, includes atomizing at least one component of the metal oxide layer by highly ionized, high power pulsed magnetron sputtering to condense on the substrate. The pulses of the magnetron have a peak power density of more than 1.5 kW/cm2, the pulses of the magnetron have a duration of ≦200 μs, and the average increase in current density during ignition of the plasma within an interval, which is ≦0.025 ms, is at least 106 A/(ms cm2).

A control and monitoring system controls and monitors a high power laser system for performing high power laser operations. The control and monitoring system is configured to perform high power laser operation on, and in, remote and difficult to access locations.

A drill bit having a bit body, at least one blade extending radially from the bit body, a plurality of blade cutting elements disposed on each blade, at least one journal extending downwardly and radially outward from a longitudinal axis of the drill bit, a roller cone or roller disc mounted rotatably to each journal, and a plurality of cutting elements disposed on each roller cone or roller disc, and methods for making the drill bit are disclosed.

A camera array, an imaging device and/or a method for capturing image that employ a plurality of imagers fabricated on a substrate is provided. Each imager includes a plurality of pixels. The plurality of imagers include a first imager having a first imaging characteristics and a second imager having a second imaging characteristics. The images generated by the plurality of imagers are processed to obtain an enhanced image compared to images captured by the imagers. Each imager may be associated with an optical element fabricated using a wafer level optics (WLO) technology.

Mass spectrometers and methods for measuring information about samples using mass spectrometry are disclosed.

A communications transmitter includes a baseband processor configured to generate amplitude, angle, in-phase and quadrature baseband signals and a combination modulator that is configurable to modulate in the polar domain and, alternatively, in the quadrature domain. The combination modulator includes a quadrature modulator and a separate and distinct angle modulator that is configured to serve as a local oscillator for the quadrature modulator. In one embodiment of the invention the combination modulator is configured to modulate in the quadrature domain when the transmitter is operating according to a first communications condition (e.g., first transmit power level or first modulation scheme) and is configured to modulate in the polar domain when the transmitter is operating according to a second communications condition (e.g., second transmit power level or second modulation scheme).

Embodiments of digital high-speed bi-phase modulator and method for bi-phase modulation are generally described herein. In some embodiments, the digital high-speed bi-phase modulator comprises a high-speed digital divider, a high-speed digital multiplexer, and matched signal paths provided between the divider and the multiplexer. The high-speed digital divider is configured to receive a carrier signal and generate complementary output signals. The high-speed digital multiplexer is configured to switch between the complementary output signals and generate a bi-phase modulated output at a carrier frequency (fc) modulated with a bi-phase code. The bi-phase code may be provided to control inputs of the multiplexer.

In various embodiments, systems and methods for generating high-precision pulse-width modulation include a delay-locked loop comprising multiple delay units having time-variable delays, control logic for selecting a subset S of the multiple delay units to thereby generate a time-invariant shift amount having a precision finer than that of a system clock and circuitry for applying the shift amount to rising and falling edges of a pulse-width modulation waveform to thereby generate a high-precision pulse-width modulation waveform.

This disclosure relates to methods and systems to reduce high voltage breakdown jitters in liquid dielectric switches. In particular, dielectric liquids have been produced that contain a suspension of nanoparticles and a surfactant to reduce the breakdown jitter. In one embodiment, the suspended nanoparticles are Barium Strontium Titanate (BST) nanoparticles.

An electric switch for application to high- and very high-voltage circuit breakers and switches comprising a flexible toroidal helical spring (8) placed in a groove of a control rod (1) carrying a movable resistance-insertion contact (2), and springs (4) placed about the movable resistance-insertion contact to cause the springs to be compressed until a certain value is reached, at which value the movable resistance-insertion contact causes the flexible toroidal helical spring (8) to deform under pressure enabling the movable resistance-insertion contact (2) to be withdrawn. Among other uses, the switch is suitable for use in a resistance-inserting device that does not need additional mechanical moving parts. For application to high- and very high-voltage circuit breakers and switches.

A sealed solenoid, magnetically operated electric power switch is suitable for use as capacitor, line and load switch operating at transmission and distribution voltages that includes no dynamically moving seals through the sealed container housing the contactor portion of the switch. The sealed solenoid switch includes a magnetically operated drive system with an actuator that magnetically couples across the container wall to avoid the use of a moving or sliding seal as part of the drive system. The sealed solenoid switch may also include a ballast resistor and resistor contact located inside the sealed container to avoid another seal as part of the ballast system. A magnetic latch holds the switch in a closed position, and a spring holds the switch in the closed position, to avoid the need for an energizing current to maintain the switch in either position.

The high voltage relay consists of a main body (1). One set of electrical contacts (2a, 2b) upper and lower respectively. High voltage connections to connect the voltage being switched (3a, 3b) are electrically connected to the upper and lower contacts respectively. Several size options for the electrical contacts will allow for a wide range of currents. A cylinder (4) driven by a fluid (e.g. Air, Nitrogen, Hydraulic fluid) moves the electrical contacts together during the ON state of the device. During the OFF state of the device the cylinder moves the electrical contacts apart to isolate the switch voltage. The greater the High Voltage being switched the greater the distance the electrical contacts must be moved apart in the OFF state. The cylinder is supplied the fluid power from a small solenoid (5) on the device. This solenoid has control voltage connections to actuate the device.

An electrode assembly for a circuit breaker is provided. The electrode assembly includes a conductive assembly and a heat transfer assembly. The conductive assembly includes a stem portion and a contact portion. The heat transfer assembly includes a number of elongated bodies, a first heat transfer surface, and a second heat transfer surface. The first heat transfer surface is disposed on the conductive assembly. Each heat transfer assembly body includes a second heat transfer surface. Each heat transfer assembly body is coupled to the conductive assembly with the first heat transfer surface coupled to a number of second heat transfer surfaces.

A highlighter strip including adhesive to form a removable bond with a substrate, constructed from a translucent and colored material. The highlighter strip can be affixed over writing or other markings, which highlights the indicia that remains legible. One or both ends of the strip can omit the adhesive, thereby providing a grabbing portion to facilitate removal from an initial position and optionally subsequent positions. The strip can be included in a set of strips affixed to each other and optionally affixed to another base; such as a notebook, binder, or other entity where one would expect writing, text, or other indicia requiring highlighting.

An amplifying structure includes a main amplifier configured to amplify a first signal; and a peak amplifier configured to amplify a second signal, each of the main amplifier and the peak amplifier including, respectively, a hybrid power device, the hybrid power device including, a first power transistor die configured to amplify signals of a first frequency, and a second power transistor die configured to amplify signals of a second frequency different than the first frequency.

Embodiments include systems and methods for accurately controlling gain of a high-speed variable-gain amplifier (VGA) without adversely impacting bandwidth performance. Embodiments include a VGA with a variable resistor, for which resistance is a function of a control level. A gain calibration system controls the control level by using a gain control feedback subsystem to sample outputs of a duplicate VGA, which includes a duplicate variable resistor. The sampled duplicate outputs are compared to a target gain generated by a reference generator. The control level can be fed back to control the gain of the duplicate VGA until the target gain is reached. The control level can also be fed to the actual VGA to control its gain. By performing gain control on the duplicate VGA without interfering with the output signal path of the actual VGA, the actual VGA's gain can be accurately controlled without impacting its bandwidth.

High impedance, high frequency nanoscale device electronics configured to interface with low impedance loads include an impedance transforming stage constructed of multiple nanoscale devices, such as carbon nanotube field-effect transistors. In an embodiment of the present invention, an impedance transforming output stage of a multistage amplifier is configured to drive a 50 ohm transmission line with unity voltage gain using multiple carbon nanotube field-effect transistors in parallel. In a further embodiment, a receiver provided for an electronically steered receive array is a monolithic, lumped-element system formed from nanoscale devices and configured to interface with the external electrical systems via a single transmission line.

One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

A thin film of a low-thermionic-work-function material is maintained on the cathode of a device for producing a high-current, low-pressure gas discharge by means of sputter deposition from an auxiliary electrode. The auxiliary electrode includes a surface with a low-work-function material, such as thorium, uranium, plutonium or one of the rare earth elements, facing the cathode but at a disposition and electrical potential so as to extract ions from the gas discharge and sputter the low-work-function material onto the cathode. By continuously replenishing the cathode film, high thermionic emissions and ion plasmas can be realized and maintained over extended operating periods.

A method and apparatus are disclosed for efficient endothermic processing of liquids and the precipitation of dissolved elements and chemical compounds. Improvements over prior systems include system layout, components and modes of operation of the system. Applications of the system include destruction of toxic wastes and sewage treatment, precipitation of chemical compounds and elements including metals from solution (brine, sea water, industrial waste), sterilization and water purification, catalytic formation of chemical compounds, and processing of hydrocarbons.

An auxiliary lighting system for a high-intensity discharge lamp. In one embodiment, the auxiliary lighting system has an auxiliary light source, an HID lamp status circuit having an input for connection to a status signal representative of the operational state of a high-intensity discharge lamp wherein the HID lamp status circuit determines whether the status signal meets predetermined signal criteria, a switch circuit having a first state that effects application of a voltage source to the auxiliary light source, and a second state that isolates the voltage source from the auxiliary light source, and a control circuit responsive to the HID lamp status circuit for controlling the switch circuit. The control circuit has a first state when the HID lamp status circuit determines that the status signal meets the predetermined signal criteria and a second state when the HID lamp status circuit determines that the status signal does not meet the predetermined signal criteria. When the control circuit is in the first state, the control circuit outputs a control signal for input into the switch circuit that configures the switch circuit into the first state. When the control circuit is in the second state, the control circuit outputs a control signal for input into the switch circuit that configures the switch circuit into the second state.

The present invention is a serial to parallel data conversion method and device where new serial data are stored within a first n-bit register prior to presentation at an n-bit parallel output. Subsequently, additional data are stored within a second n-bit register while the data stored within the first register are presented at the parallel output. Data storage and data presentation are thereafter alternated, thereby eliminating the problem of setup time seen in prior art.

High pressure pump systems with reduced pressure ripple for use with waterjet systems and other systems are described herein. A pump system configured in accordance with a particular embodiment includes four reciprocating members operably coupled to a crankshaft at 90 degree phase angles. The reciprocating members can include plungers operably disposed in corresponding cylinders and configured to compress fluid (e.g., water) in the cylinders to pressures suitable for waterjet processing, such as pressures exceeding 30,000 psi.

A device for coupling tilting railroad cars onto a high-speed railroad train comprises a coupler and a shock absorber held in a shock absorber frame, each joined by a coupling pin via a coupling joint. The frame includes a front inner surface with a front end wall opening and a cylindrical surface extending to a semi-circular concave inner surface. The joint includes a rounded convex surface engaged with a semi-circular concave surface, a circumferential surface of a short cylinder receiving the rear portion of the coupler, and an insertion hole which is provided in a direction perpendicular to the axis of the short cylinder. The frame has a removal hole and an air removal pin of the coupling pin facing each other at a position to rotate at a predetermined angle in a circumferential direction in the assembled state, and at a position coaxial with the coupling pin in the assembled state.

Disclosed is a method of producing a chemically pure and stably dispersed organic nanoparticle colloidal suspension using an ultrafast pulsed laser ablation process. The method comprises irradiating a target of an organic compound material in contact with a poor solvent with ultrashort laser pulses at a high repetition rate and collecting the nanoparticles of the organic compound produced. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beam, an organic compound target in contact with a poor solvent, and a solvent circulating system to cool the laser focal volume and collect the produced nanoparticle products. By controlling various laser parameters, and with optional poor solvent flow movement, the method provides stable colloids of dispersed organic nanoparticles in the poor solvent in the absence of any stabilizing agents.

High-altitude balloons and apparatuses for filling such high-altitude balloons are provided. As an example, an apparatus for filling a high-altitude balloon includes a tube extending through envelope material of the balloon is provided. The apparatus also includes a flange connected to a first end of the tube. The flange is connected to an interior surface of the balloon. A fitting is connected to a second end of the tube. The fitting is configured for attachment with an apparatus for filling the balloon with lift gas. In addition, methods of filing high-altitude balloons with lift gas and methods of manufacturing balloons are also provided.

A controller used in a buck-boost converter includes a clock generator, an error amplifying circuit, a comparing circuit, a proportional sampling circuit, a logic circuit, a pulse width increasing circuit, first and second driving circuits. Based on a clock signal generated by the clock generator, the proportional sampling circuit samples the difference between a current sensing signal and a compensation signal generated by the error amplifying circuit, and generates a proportional sampling signal. The pulse width increasing circuit generates a sum control signal based on the proportional sampling signal and a logic control signal generated by the logic circuit, wherein a modulation value adjusted by the proportional sampling signal is added to the pulse width of the logic control signal to generate the pulse width of the sum control signal. The first and second driving circuits generate driving signals based on the sum control signal and the logic control signal.

In various embodiments a controller for controlling the operation of a switched mode power supply is provided, the controller comprising: a first signal source configured to provide a first set of signals including a set signal and a clear signal, wherein the first set of signals may correspond to a first mode of operation of the switched mode power supply; a second signal source configured to provide a second set of signals including a set signal and a clear signal, wherein the second set of signals may correspond to a second mode of operation of the switched mode power supply; a selecting circuit coupled to the first signal source and to the second signal source, the selecting circuit being configured to select either the first set of signals or the second set of signals; a switching signal generating circuit coupled to the selecting circuit and configured to provide a switching signal to the switched mode power supply based on the set of signals received from the selecting circuit.

A passively torque-balanced device includes (a) a frame; (b) a drivetrain including a drive actuator mounted to the frame and configured for reciprocating displacement, an input platform configured for displacement by the drive actuator, a plurality of rigid links, including a proximate link and remote links, wherein the rigid links are collectively mounted to the frame, and a plurality of joints joining the rigid links and providing a plurality of non-fully actuated degrees of freedom for displacement of the rigid links, the plurality of joints including a fulcrum joint that is joined both to the input platform and to the proximate rigid link; and (c) at least two end effectors respectively coupled with the remote links and configured for displacement without full actuation.

There are provided a dividing wall distillation column for producing high-purity acrylic acid, and a fractional distillation method using the same. The dividing wall distillation column includes a condenser, a reboiler and a main column having a dividing wall. Here, the main column is divided into a column-top zone, an upper feed zone, an upper outflow zone, a lower feed zone, a lower outflow zone and a column-bottom zone. Accordingly, since one distillation column can be used to realize the same effect as that obtained from the use of two distillation columns, the dividing wall distillation column can have an effect of reducing the costs of equipment to produce high-purity acrylic acid, as well as an energy-reducing effect, compared to a conventional process system.

This invention relates to a high efficiency apparatus for manufacturing an aqueous wood smoke solution in the form of a liquid smoke desired concentration by burning wood, wooden chips or sawdust in a limited amount of air. Wood consumption per unit of liquid smoke is significantly smaller comparing to conventional methods, while the air pollution is reduced to a negligible level.

A highly loaded concentrate pellet composition includes an active ingredient in a concentration of at least about 60% by weight, and a low molecular weight binder in a concentration of up to about 35% by weight. The active ingredient is evenly dispersed in the binder. The binder has a melting point that permits the composition to melt under shear in an extruder. The binder is non-metallocene and non-stearic.

In one featured embodiment, a spring assembly for a valve comprises a spring, a spring seat including a cup-shaped portion for seating one end of the spring, and a ball received within a recess formed within the cup-shaped portion of the spring seat. The ball is defined by a ball diameter. A disc prevents the ball from contacting a piston. The disc is defined by an outer diameter and includes a center opening defined by an inner diameter. A ratio of the inner diameter to the ball diameter is between 0.60 and 0.65.

The invention relates to a high-precision revolving center (10) for machine tools. Prestressed bearings 40 and 45 are brought into abutment on the one hand against internal 33 and external 25 cylindrical surfaces whose deviation, at any point on the surface, with respect to the theoretical surfaces centered on the axis, is less than 1 μm, and on the other hand against reference surfaces 26 and 34 perpendicular to the axis. Threaded elements 50, 55 enable the bearings 40, 45 to be stressed. Once the center 10 has been assembled and the bearings stressed, the revolving center is mounted on a grinder in order to give a precision finish to the tip 90, the concentricity reference surface 91 and the perpendicularity reference surface 92.