Abstract: A vacuum pump is provided with back-up bearings in addition to magnetic bearings for supporting its rotor with respect to the pump housing. The rotor has a hollow rotary shaft extending backwards enclosing in its inner space a forwardly protruding tubular shaft affixed to the pump housing, and another cylindrical member affixed to the rotor protrudes backward inside this fixed tubular shaft. One set of back-up bearings is provided on the outer surface of the fixed tubular shaft spaced from the inner surface of the rotor shaft and another set of back-up bearings is provided on the inner surface of the fixed tubular shaft, spaced from the protruding cylindrical member. The back-up bearings thus positioned can be made smaller for improved dynamic emergency capabilities.

Abstract: The present invention is directed to a cooling system and apparatus for use in radiographic devices having high output x-ray tubes. In operation, the x-ray tube generates large amounts of heat that must be removed so as to prevent damage to the tube. In the present invention, the x-ray tube is disposed within an x-ray tube housing that is connected within a closed fluid circuit through which circulates a coolant fluid. The fluid circulates through the x-ray tube housing and absorbs heat dissipated by the x-ray tube. Also connected within the closed fluid circuit is a heat exchange which cools the coolant fluid before it is recirculated back to the x-ray tube housing. Also connected within the closed fluid circuit is a centrifugal pump which continuously circulates the coolant fluid between the x-ray tube housing and the heat exchange device. The pump includes as an integral part a deformable bellows that accomodates any volume changes with the closed fluid system due to increases in temperature.

Abstract: An X-ray tube device and a method for construction thereof which provides the cathode assembly and the anode assembly in a nose of the X-ray tube, wherein an emitter face of each assembly is directed toward an X-ray emission end thereof. The electrons emitted from the cathode assembly travel along a path outward until striking the anode assembly which then generates the X-rays which are directed toward a beryllium window in the X-ray tube. This advantageous structure enables the anode-to-window distance to be small, resulting in a large X-ray flux towards a sample. Furthermore, the small nose of the X-ray tube enables a fluorescence detector to be positioned in an optimal location because the X-ray tube's shape does not displace the fluorescence detector.

Abstract: A vacuum pump has a back-up bearing assembly for allowing its rotor to spin down safely without damaging the pump if the primary bearing system becomes disabled. The drive shaft of the rotor is tubular and contains the back-up bearing assembly in its hollow interior. Back-up bearings are mounted onto a tubular center shaft which is coaxial with and inside the drive shaft. An axial position sensor is nested inside the center shaft and light emitted from its light emitter is reflected by a reflective target inside the drive shaft to detect the relative axial position of the drive shaft with respect to the center shaft. A polymer sleeve is attached to the end of the drive shaft as a thermal compensator, which restricts the axial movement of the drive shaft.

Abstract: A tip seal for use in a scroll-type vacuum pump includes a seal element and an energizer element affixed to the seal element. The scroll-type vacuum pump includes first and second scroll blades that are nested together to define one or more interblade pockets, and an eccentric drive that produces orbiting movement of the first scroll blade relative to the second scroll blade. At least one of the first and second scroll blades has a seal groove along an edge thereof. The tip seal is positioned in the seal groove between the first and second scroll blades. The energizer element is formed of a resilient material having multiple compressible voids, so that the energizer element having compressible voids is more compressible than the resilient material alone, when confined by the seal groove. In one embodiment, the energizer element is a foam such as a low porosity urethane foam. In another embodiment, the energizer element is an elastomer material having a predetermined pattern of voids.

Abstract: A mass spectrometer system with electrospray ion source for generating ions at atmospheric pressure and an ion trap mass analyzer has an improved ion optics for transporting ions from the atmospheric pressure region to the ion trap mass analyzer region. The system comprises a short ion guide having a predetermined characteristic length to radius ratio. The ion guide is coupled to the ion trap mass analyzer via an electrostatic ion optics. The electrostatic ion optics comprises an ion guide extraction optics and an ion trap mass analyzer injection optics. The ion guide extraction optics comprises the ion optical electrode with an aperture that is coupled to an exit of the ion guide and serves as a differential pressure restrictor between the vacuum chamber with the ion guide and the vacuum chamber with the ion trap mass analyzer. The design of the ion optics is tolerant to the mechanical imperfections in the ion optical system and practically eliminates the non-linear matrix effects.

Abstract: An architecture for mixed SONET/WDM networks using one dedicated protection ring for protection of several WDM links deployed along the same SONET ring by providing optical switching equipment for switching telecommunication traffic from working optical fibers of failed WDM links to protection optical fibers of the dedicated SONET ring selected for that purpose from the plurality of SONET rings of the mixed SONET/WDM network.

Abstract: A graphite-backed metallic x-ray tube target assembly has a rotary shaft which passes through the central opening of the annular graphite substrate and is secured to the metallic disk-shaped target. In order to protect the shaft from heat radiated from the graphite substrate, at least one tubular heat shield is brazed to the target and disposed between and separate from the inner wall of the annular graphite substrate and the outer peripheral surface of the shaft. For further protection, a tubular heat shielding member may be disposed inside the other heat shield, between the outer heat shield and the shaft. In order to minimize the heat conduction from the outer heat shield to the inner heat shielding member, they are mostly separated and attached to each other only along their bottom edges where they are tack-welded together at mutually separated positions such that the inner heat shielding member is supported entirely by the outer heat shield.

Abstract: A service restoration system and method for a mixed SONET/WDM optical fiber telecommunication networks comprising a plurality of self healing SONET rings and at least one WDM link which is shared by these SONET rings, provides protection on the optical layer of at least one WDM link in case of fiber or cable cut. The WDM link protection is provided by rerouting the WDM link traffic through a dedicated protection ring which is selected from the plurality of self healing SONET rings, via color blind optical fiber-to-fiber switches. The WDM working equipment protection is provided by rerouting the SONET traffic via additional optical switches and wavelength converters through WDM link. Wavelength converter aligns the wavelength of the optical signal to match the wavelength of failed WDM channel, to localize and heal the failure of the WDM working equipment without reporting to the adjacent nodes.

Abstract: The invention concerns a vacuum pumping device comprising: a vacuum pump (100) having a casing (101), provided with a suction port (119) and an exhaust port (120), in which there is defined a first portion (102), housing the gas pumping stages formed by rotor disks (113, 114) secured to a pump rotatable shaft (123), and stator rings (115, 116) secured to the vacuum pump casing and cooperating with said rotor disks (113, 114); and a second portion (103) housing the electric motor (121) of the vacuum pump and at least one bearing (122) for supporting the shaft (123); an electronic control unit (1) comprising a housing (2) defining an inner space (17) containing the electronic components of an electronic circuit feeding the electric motor (121), and wherein at least the second portion (103) of the pump casing (101) is located within the inner space (17) containing the electronic components.

Abstract: Vacuum pumping apparatus includes a non-scroll type auxiliary pump and a scroll pump disposed in a single housing. The auxiliary pump and the scroll pump are connected in series and are driven by a common motor. Typically, the auxiliary pump has a relatively high pumping speed and the scroll pump has a relatively high compression ratio. The auxiliary pump may be a regenerative blower, a roots-type blower or a screw-type blower. When a co-rotating scroll pump is utilized, a regenerative blower may be formed at or near the outer periphery of a disk on which the non-orbiting scroll blade is mounted. In another configuration, first and second scroll pumps are disposed within a housing. The scroll blade sets of the first and second scroll pumps have different orbiting radii. Scroll pump leakage may be reduced by forming a closed-loop seal around the inlet region of the scroll pump and connecting the inlet region to an intermediate pressure.

Abstract: A new target anode for use in x-ray equipment where it is subjected to high speed rotations and thermal stress, wherein the target anode is comprised of a substrate which has coated thereon an x-ray emissive, high-Z metallic material or metal carbide which functions as the focal track, wherein a surface on the substrate to which the high-Z metallic material or metal carbides is deposited and bonded consists of directionally oriented fibers of high thermal conductivity, and wherein the directionally oriented fibers are bonded to the substrate and facilitate bonding between the substrate and the x-ray emissive, high-Z metallic material or metal carbide.

Abstract: The invention is concerned with an electronic control unit (1) for the electric motor of a vacuum pump (100) comprising a suction port (119), an exhaust port (120) and pumping stages formed by rotor disks (113, 114) secured to a rotating shaft driven by an electric motor, and stator rings (115, 116) secured to a pump housing (101) and cooperating with said rotor disks. The unit (1) comprises: a housing (2), first leads (50) for electrically feeding the control unit, second leads (60) for electrically feeding the motor of the pump (100), a circuit for generating a voltage adapted to feed the motor, the circuit generating drive signals (A, B, D, E, G, H, PWM) and providing at least a pulsating signal (PWM the width of which for combining said drive signals can be modulated, and means (201, 202, 203) for combining the, pulsating signal (PWM) with at least one of the drive signals (A, D, G) so as to change the rms voltage of said voltage system.

Abstract: The workable range is extended into lower pressure region for micromechanical pressure sensors of the kind having a vibrating mass in proximity of a stationary surface by increasing the amount of squeeze damping. The amount of squeeze damping is increased by using the symmetry of a circular disk-shaped vibrating mass and restricting or changing the flow path of the gas in and out of a squeeze damping space. A circular vibrating mass is supported through an annular spring by a support ring attached to the substrate surface by a plurality of mesas which serve to block the gas flow into and out of the squeeze damping space between the mass and the substrate surface. The amount of squeeze damping may be increased by providing the support ring which completely encloses the squeeze damping space with the vibrating mass having a hole through which the gas may enter and leave the space.

Abstract: The present invention relates to a rotor of a vacuum pump comprising a rotatable shaft and a plurality of spaced apart parallel rotor disks secured to said rotatable shaft, such rotor being provided with a corrosion-resistant protective coating formed by a layer of polymeric material.

Abstract: A fluid handling apparatus, particularly a vacuum pump, has as a first stage a high volumetric displacement rate scroll pump of multiple nested interacting pairs of fixed and movable spiral-shaped blades supported in a housing between an inlet and an outlet. Each adjacent blade pair closes one inter-blade pocket in each cycle of operation. For very low base pressure vacuum applications, the adjacent blades extend about two revolutions to produce plural pockets in series. A second scroll pump mounted in the housing has its inlet fed directly from the first scroll outlet. The second scroll has a single pair of co-acting fixed and movable blades with multiple revolutions. A central drive shaft rotating in main bearings has an eccentric portion coupled to a plate that carries the movable blades of both scroll pumps. Synchronization cranks constrain the plate to orbit, not rotate. A purge gas flows over the crank bearings to sweep away and/or dilute corrosive fluids.

Abstract: A method and apparatus for superimposing a plurality of electron beams at a desired location after X-ray tube manufacturing processes are generally complete. The method is embodied in providing mechanical and electrical means which are internal to the X-ray tube which provide means for adjustment of a focal point of a plurality of electron beams being emitted from a cathode assembly to thereby provide precise control of where the plurality of electron beams achieve superimposition on a target anode.

Abstract: A rotatable assembly for supporting the rotor of a vacuum pump with a plurality of gas pumping stages formed by cooperating rotor discs secured to the rotor and stator rings integral with a body, comprising rotatable means for supporting the shaft of the rotor that are housed within this shaft.

Abstract: A rotating anode X-ray target has a matrix structure such as a carbon-carbon matrix and a high Z material imbedded inside this matrix structure. The high Z material may be a refractory metal with atomic number at least 72, its alloy or carbide and may be imbedded in the matrix either as discrete particles or as a non-discrete layer. Such a target can be made by any of a number of known methods such as chemical vapor deposition and chemical vapor infiltration. Without a TZM layer or a braze required for holding together an x-ray-producing surface layer and a carbon heat storage material, the target can be made lighter and can be operated at higher temperatures.

Abstract: A mass spectrometer system for performing a separation of ions from neutrals and mass analyzing ions comprising a inductively coupled plasma ion generating source with an ion introducing system, a radio-frequently ion guide and a mass analyzer disposed within a vacuum chamber. The space between the radio-frequency ion guide and the ion introduction system defined an aerodynamic jet region which is used for directing a sample containing ions to be analyzed to the entrance of a radio-frequency ion guide and the via the radio-frequency ion guide to the mass analyzer.