Abstract: An intake and exhaust fan assembly is provided having a motor and fan assembly mounted for movement on rails toward and away from a rotatable blade damper mounted on an angle to the motor/fan assembly.

Abstract: The object of the invention is to provide a method of operating a simply constructed centrifugal compressor equipped, in the region of the rear wall of the compressor impeller, with no sealing elements in the separating gap between the compressor impeller and the compressor casing, which method increases the service life of the centrifugal compressor. An appliance for carrying out the method is also to be made available. In accordance with the invention, this is achieved by introducing a cooling medium into the separating gap downstream of the leakage flow of the working medium and by finally removing this again after the cooling process has taken place. For this purpose, at least one supply duct for a gaseous cooling medium, the duct penetrating the compressor casing, opening into the separating gap in the region of the rear wall of the compressor impeller and directed onto the rear wall, and at least one removal duct for the cooling medium are arranged in the compressor casing.

Abstract: A gas turbine engine seal system includes a rotating member having an abrasive tip disposed in rub relationship to a stationary, abradable seal surface. The abrasive tip comprises a zirconium oxide abrasive coat having a columnar structure that is harder than the abradable seal surface such that the abrasive tip can cut the abradable seal surface.

Abstract: The objects of the present invention are to improve the fan efficiency by the decrease of the shaft power of a fan and/or the increase of the pressure rise owing to a fan impeller, which are accomplished by the rational control of the energy based on the tangential velocity of the prerotation flow generating at ‘the region ahead of an impeller’ inside the suction pipe of a fan, and to reduce fan noise by the improvement of air flow at the portion in close vicinity to an impeller inside the suction pipe. The present invention is related to a by-pass unit (5) disposed upstream an impeller to control the energy generated by the air flowing into the impeller (1), comprising a specific region of a suction pipe (2) as a part of the by-pass unit (5), an air chamber (3), through which the air is able to pass, forming a closed spatial region outside the suction pipe (2), and communicating passages (4) for connecting the closed spatial region to the suction pipe (2).

Abstract: A fan impeller assembly of simple construction which is intended, in particular, for use in cooling systems of internal combustion engines and can be used there inter alia as a cleaning blower for clearing the radiator and/or corresponding air inlet openings by reversal of the direction of delivery.

Abstract: In a turbine rotor, an aft shaft wheel and the final-stage wheel of the rotor are coupled together, including by a rabbeted joint. During shutdown and startup of the turbine, a thermal mismatch between the aft shaft wheel and final-stage wheel is avoided by respectively heating and cooling the aft shaft wheel to maintain the thermal mismatch within acceptable limits, thereby avoiding opening of the rabbeted joint and the potential for unbalancing the rotor and rotor vibration. The thermal medium may be supplied by piping in the aft bearing cavity into the cavity between the forward closure plate and the aft shaft wheel.

Abstract: A cooled moving blade for a gas turbine which has a blade profile capable of more effectively reducing thermal stress in a blade base portion and, thus, preventing cracks from occurring. A moving blade (1) is fixedly secured to a platform (2). On the other hand, a cooling air passage (3) is formed in a serpentine pattern inside of the blade for cooling with cooling air. The moving blade (1) has a base portion of a profile formed by an elliptically curved surface (11) and a rectilinear surface portion (12), wherein the rectilinear surface portion (12) is provided at a hub portion of the blade where thermal stress is large. The cross-sectional area of the blade is increased by providing the rectilinear surface portion (12) The heat capacity is increased, compared with the conventional blade, due to the increased cross-sectional area of the blade. This, in turn, results in a decrease of the temperature difference due to the thermal stress.

Abstract: A gas turbine engine rotor blade 18 includes a dovetail 22 and integral airfoil 24. The airfoil includes a pair of sidewalls 28,30 extending between leading and trailing edges 32,34, and longitudinally between a root 36 and tip 38. The sidewalls are spaced laterally apart to define a flow channel 40 for channeling cooling air through the airfoil. The tip includes a floor 48 atop the flow channel, and a pair of ribs 50,52 laterally offset from respective sidewalls. The ribs are longitudinally tapered for increasing cooling conduction thereof.

Abstract: A gas turbine moving blade platform having a simplified platform cooling structure. A cooling effect of the platform side end portions is increased resulting in uniform cooling of the entire platform. Cooling passages (2, 3) are bored in the platform (1) front portion so as to communicate with a cooling air passage (52) of the moving blade (51) and open at both platform side end surfaces. The openings are closed by inserting covers (2a, 2b) therein. Cooling passages (6, 4) are bored in platform (1) side end portions so as to communicate with the front end cooling passages (2, 3), respectively, and open in the platform rear end surface. A plurality of cooling holes (5) are bored so as to communicate with the cooling passage (4) and open at the platform side end surface. Thus, the entire platform is cooled uniformly and the platform side portions are cooled by the cooling holes (5) so that an effective cooling performance is ensured and also the workability of the cooling lines is enhanced.

Abstract: Coverplates are disposed to axially overlie end faces of the shanks of buckets and the dovetail connections of the buckets within turbine wheel slots. The coverplates have axially projecting angel wing seals. The coverplates also have balance weights on axial faces thereof opposite the angel wing seals to balance out any bending moments applied to the coverplate resulting from centrifugal forces when the turbine rotor is at speed. Thus, the centers of gravity of the coverplates are located close to or in the plane of the coverplates. A centering slot is provided along an inner face of each dovetail connection for the coverplates. Coverplate retention pins reside in wide sub-slots at the bases of the wheel slots. When the coverplates are secured against axial movement, the retention pins engage in the centering slots of the coverplate dovetails to prevent circumferential movement of the retention pins in the wide sub-slots.

Abstract: A blade root portion of a rotor blade is attached to a rotor head for rotating. A center portion linearly elongates from the blade root portion. A blade tip portion outward elongates from the center portion and has a shape which is defined by a leading edge, a side edge and a trailing edge, and has a predetermined aerofoil. In the leading edge of the blade tip portion, a swept-back angle &lgr;(r) at a distance r from the rotation center of a rotor satisfies relational expression (1) of a rotor blade length R of a rotorcraft, a maximum flight Mach number M∞ which is a flight limit speed of the rotorcraft, a blade tip Mach number MTIP which is a tip speed during hovering, and a drag divergence Mach number Mdd which is determined from the aerofoil of the blade tip portion.

Abstract: A cast metallic airfoil structure having a high stiffness core positioned therein for increasing the stiffness of the airfoil. In one embodiment, the high stiffness core is preferably formed of gamma titanium aluminde or a titanium metal matrix composite and is metallurgically bonded to the cast metallic airfoil structure. In one form the airfoil structure forms a portion of an integrally bladed rotor, and in a second form the airfoil structure has a dove tail attachment portion.

Abstract: The apparatus includes a motor with a shaft for rotating a fan. A retaining ring and a thrust washer are located around the shaft on one side of the hub of the fan and a torque washer is located on the outer side of the hub with the end of the shaft extending through a central aperture of the torque washer. The retaining ring supports the thrust washer and the thrust washer engages and supports the hub of the fan. The aperture of the torque washer and the side of the shaft at the end thereof have planar surfaces which engage each other which prevents rotation between the torque washer and the shaft. Bosses are formed on the outer side of the hub which fit into apertures formed through the torque washer outward of the central aperture to transfer torque radially outward to the hub. A screw has a threaded shaft extending through the central aperture of the torque washer and which is screwed into a threaded aperture formed in the end of the motor shaft to tighten the torque washer to the hub.

Abstract: A cover for a fan (2) which can be mounted on a base (3) for cooling electric sub-assemblies or elements which are located on the base (3) characterized by a cover plate (4) which is equipped with air through-flow openings (5) as well as by fastener elements (10) for the fan which are connected to the cover plate (4) and by elements (11a, 11b) for the base (3) where the fastener elements (10, 11a, 11b) are constructed in such a manner that the cover plate (4) can be detachably attached to the base (3) in the position where it is placed at a distance from the base (3) and where the fan (2), which can be attached to the cover plate (4), is located in an intermediate position.

Abstract: A diaphragm failure sensing apparatus for use in a diaphragm pump having at least two pumping cavities, each pumping cavity having a fluid chamber and a motive gas chamber separated by a pumping diaphragm. The diaphragm failure sensing apparatus includes a fluid conduit for connection with each of the motive gas chambers of the diaphragm pump, a sensor chamber connected to the fluid conduit, and a check valve located in the fluid conduit for alternately connecting the sensor chamber to the motive gas chambers. Also provided is a diaphragm pump having at least two pumping cavities, each pumping cavity having a fluid chamber and a motive gas chamber separated by a pumping diaphragm. A fluid conduit is disposed between and connected individually to each of the motive gas chambers and a sensor chamber is connected to the fluid conduit which is alternately connected to the motive gas chambers by a check valve located in the fluid conduit.

Abstract: A reciprocating piston compressor having at least one cylinder, a reciprocable piston disposed in the cylinder, a crankshaft rotatable in both a forward and a reverse direction, the crankshaft having a cylindrical eccentric portion, a latching member pivotally engaged with the crankshaft, a cam disposed about the crankshaft eccentric portion, the piston operatively connected to the cam, and a spring connected to one of the cam and the crankshaft, the position of the latching member influenced by the spring. The cam is rotatable about the crankshaft eccentric portion between a first cam position corresponding to a first piston stroke length during forward rotation of the crankshaft, and a second cam position corresponding to a second piston stroke length during reverse rotation of the crankshaft. In one of the first and second cam positions, the cam is rotatably locked to the crankshaft eccentric portion by the latching member.

Abstract: A scroll compressor has a valve normally closed during forward operation of the scroll compressor. Upon reverse rotation, force imbalances allow the valve to open and communicate a chamber downstream of a check valve to a chamber upstream of the check valve. By communicating these two chambers, the detrimental effects of reverse rotation are reduced or eliminated. Two valve embodiments are disclosed. One embodiment also relieves unduly high discharge pressures. In a third embodiment, a pressure relief valve is provided to prevent desirably high pressure ratios or pressure differentials.

Abstract: A filter for a piston type high-pressure fuel pump is not clogged from freezing even under a hostile condition. The filter is provided in a fuel intake route (26) of a piston type high-pressure fuel pump, and it has many square openings. The length of one side of each opening ranges from 50 &mgr;m to 200 &mgr;m.

Abstract: High volume, belt-driven ventilation fans in which the bladed propeller assembly and the drive motor are operationally mounted upon a unitary structure. In one form of the invention a box-fan comprises a generally cubicle, or parallelepiped housing. In an alternative barrel fan the tubular housing is cylindrical. Both fans comprise a pair of rigid, vertically upright, parallel rails within their interior. A rigid, X-profiled mounting unit is fastened between the rails to mount both the propeller and the motor. The unitary mount comprises a rigid, central mandrel that coaxially receives the propeller assembly axle. Pairs of diverging arms extending away from each side of the mandrel are fastened to the rails within the fan interior. One of the arms pivotally supports a deflectable wing upon which the motor is mounted. The propeller assembly comprises a pulley-driven blade centered within the housing and an axle captivated within the mandrel.

Abstract: An electrical submersible pump assembly has a diluent fluid injection line to reduce viscosity of well fluid. The electrical submersible pump includes impellers for displacing well fluids, and a base member having an intake port for receiving well fluid. An inducer having a helical flight is mounted below the impellers in the base member. The submersible pump is additionally provided with injection ports, preferably radially spaced around the base member proximate the inducer through which diluent is injected for mixing with the well fluid. The diluent is pumped down to the injection ports by an injection line that runs down from the surface.

Abstract: A manual air pump includes an outer tube and an inner tube coaxially mounted in the outer tube. An inner chamber is defined in the inner tube. An outer chamber is defined between the outer tube and the inner tube. A head is coupled to first ends of the inner and outer tubes. The head includes a main passage communicated with the inner chamber and the outer chamber for supplying air to an object to be inflated. An inner piston rod has a first end with an inner piston slidably received in the inner chamber. The inner piston separates the inner chamber into a first chamber section adjacent to the head and a second chamber section distal to the head. An outer piston rod has a first end with an outer piston slidably received in the outer chamber. The outer piston separates the outer chamber into a third chamber section adjacent to the head and a fourth chamber section distal to the head. A handle is secured to second ends of the inner and outer piston rods to move therewith.

Abstract: An improved piston-type vacuum pump comprises a reciprocating piston disposed within a cylinder having a proximal end and a distal end, an inlet port formed in the side of the cylinder near the proximal end, and a spring-biased outlet valve, such as a poppet valve or a rocker valve, disposed at the distal end of the cylinder. The piston stroke is configured to provide zero or negative clearance between the piston head and the face of the outlet valve at the end of the compression stroke. The piston reciprocates within the cylinder from a first position wherein the surface of the piston head is proximal of the inlet port, to a second position wherein the surface of the piston head is beyond the distal end of the cylinder, so as to contact the face of the outlet valve in its open position.

Abstract: A compressor having at least one cylinder in which is defined a compression chamber defined at the bottom by a piston movable along the cylinder, and at the top by a wall having a suction opening and an exhaust opening, each of which is connected to a respective conduit by a respective valve having a channel in which a sealing member slides, in opposition to a spring, from a closed position, in which the compression chamber is cut off from the respective conduit, to an open position, in which the compression chamber communicates with the respective conduit.

Abstract: The present invention is to offer a scroll fluid machine of which the scroll machine proper is cooled sufficiently and effectively and characterized in that, a tubular jacket 26 is provided, said tubular jacket surrounds the outer circumferential surface of a motor 15(motor housing 13) keeping some distance from said surface and has an annular opening 17a on said motor facing to said scroll machine proper side, from which opening cooling gas induced by a cooling fan 16 is taken in, and a passage 19 connecting to the cooling space 17 formed by said outer circumferential surface of the motor and said tubular jacket is provided to guide and introduce said taken-in cooling gas to said scroll machine proper in the direction crossing the longitudinal direction of the rotation shaft of said motor. Thus, the back side of the scroll disk of said scroll machine proper is cooled by the cooling gas flowing in one direction behind the scroll disk.

Abstract: A scroll member for scroll compressor contains a phenol aralkyl resin and a glass fiber and has feature that the dimensional change rate of the member is 0.05% or below under a chemical stability test condition conducted in an atmosphere in which a refrigerant and a refrigerating machine oil coexist at a high temperature and a high pressure, thereby making the resin scroll member practical and chemically stable. The scroll member may further contain a phenol resin and/or glass beads. The scroll member may be formed by a heat treatment having stepwise temperature increase of a molded material from an initial temperature range of 120 to 140° C. to a final temperature range of 170 to 177° C. The heat treatment can be implemented sequentially, e.g., for four hours or more at a temperature range of 120 to 140° C., for four hours or more at a temperature range of 140 to 170° C., and for four hours or more at a temperature range of 170 to 177° C.

Abstract: A rotation balancing mechanism of an orbiting scroll of a scroll-type compressor that reduces the outer diameter of the compressor housing. A compression mechanism includes a fixed scroll and an orbiting scroll. The compression mechanism is coupled to a support frame at the front of a drive motor. A drive crankshaft is located between the drive shaft of the motor and a base plate of the orbiting scroll. The drive crankshaft causes the orbiting scroll to orbit. Follower crankshafts are located between the support frame and the base plate. The follower crankshafts permit the orbiting scroll to orbit and prevent the orbiting scroll from rotating about its own axis. A central balance weight is located on the drive crankshaft. The central balance weight opposes part of the centrifugal force that is applied to the drive crankshaft when the orbiting scroll orbits. Outer balance weights are attached to the follower crankshafts to oppose the remainder of the centrifugal force.

Abstract: In a scroll-type fluid displacement compression apparatus, the structure, names as a two-way gas suction and an oil-gas mixed lubrication plate thrust bearing and a one-side Oldhams ring, makes the mixture of oil and gas, which is entered into the apparatus, flowing in two directions such that most of the working gas media is changed the flowing direction and sucked into the suction chamber of the scroll members directly while most of lubrication oil-fog flows on the sliding plate thrust bearing through certain passages and lubricates it well. The supporting area of the sliding plate thrust bearing can be enlarged due to the structure of the one-sided Oldhams rings. As a result, the displacement scroll-type fluid compression apparatus can be used in a wide variable range of speed and variable angle positions.

Abstract: An oil distribution system for machinery such as a vacuum pump is disclosed. The system features an auxiliary oil pump integrally mounted adjacent to one end of the vacuum pump's drive shaft. The drive shaft drives the oil pump and has a longitudinal passage extending substantially along its length in communication with the outlet from the oil pump. Oil ports, positioned at points along the drive shaft adjacent to bearings supporting the drive shaft, extend from the passage. Lubricating oil, drawn from a reservoir by the oil pump, is pumped into the passage. The oil exits the passage via the oil ports and lubricates the bearings. The oil passes into the pump cylinder where it provides an oil seal between the piston and cylinder wall. Either a rotary vane pump or a gerotor-type pump is preferred as the auxiliary oil pump.

Abstract: A windshield repair injector, to repair star, bulls-eye and elongated cracks in a laminated windshield. The device has a stepped threaded section for easy removal and installation. When the injector is placed against a glass surface, upward motion of a piston provides a vacuum in the piston chamber for removing moisture trapped in the damage region. Afterwards insertion of an optically clear resin, with an optical coefficient equal to glass is inserted under pressure, creating a permanent and virtually invisible repair.

Abstract: A method of making a three-dimensional object from fibers includes attaching a mold made at least in part of elastomeric material to a porous support. The mold comprises a first mold member defining at least one channel in fluid communication with the porous support. Each channel has within it at least one second mold member. A mixture of fibers and fluid carrier is poured onto the mold. Thereafter, a pressure differential is created across the mold to create a flow of the mixture toward the porous support via the second mold members. This flow causes the fluid carrier to pass through the porous support, thus depositing the fibers within the recessed parts of the second mold members in the mold. Thereafter, the mold is compressed sufficiently to deform the mold and to provide uniform, normal pressure to the fibers which have been deposited in the second mold members.

Abstract: An extrusion die with a plurality of die layers stacked one upon the other in a direction generally parallel to the central axis. Each of the layers has an annular flow distribution ring having an outer generally cylindrical surface and an annular feed ring surrounding and engaging the outer surface of the distribution ring. At the engaged surfaces of the feed and distribution ring, the flow from the feed ring is divided into a number of substantially equal flow portions. Seals between adjacent engaged surfaces confine the flow to between the circumferential surfaces of the feed and distribution ring. Half of the flow portions are directed to a recombination region on one side of the distribution ring, and half are directed to a recombination region on the other side of the ring. In recombining, weld lines are formed in high flow areas to minimize the deleterious effect of polymer degredation.

Abstract: A drawing system in which a thickness and degree of orientation of an oriented film or the like is maintained in a uniform manner under a condition of a high speed, shortened is a time required from a time when a molding material is charged in an extruder and drawing started until a time when a film is taken up on a take-up apparatus, and a high quality film or the like is produced at a high speed and besides, a probability for a not-oriented or oriented film or the like to be broken down during drawing is reduced. A thickness and degree of orientation of a film are independently measured in thickness gauges and a film orientation measuring apparatus in a continuous manner after longitudinal drawing or lateral drawing and measured values are input to a computer.

Abstract: In the case of an injection molding machine for processing plasticizable materials, a structural unit, which includes at least a movable mold carrier, a stationary mold carrier and a closing arrangement of a mold closing unit, is supported on support elements on a machine base. A pivotal axis, about which the structural unit is pivotable, extends transversely relative to a closing axis. A drive unit is provided for pivoting and for displacing the structural unit and is connected pivotally to the machine base and at an articulation point to the structural unit, which articulation point is disposed at a spacing from a pivotal axis. Upon transferring the structural unit from the horizontal position into the vertical position, the drive unit initially pivots the structural unit and then also displaces it.

Abstract: A pair of opposing shoes are alternately and successively moved into and out of contact with a ring previously formed on a prophylactic device on a mandrel, whereby the mandrel or the shoes or both are moved in a direction during each time of contact of the shoes with the rolled portion of the device, for at least partially rolling the prophylactic device up toward its closed end, with the process being repeated until the prophylactic device is rolled up and off of the mandrel.

Abstract: A continuous thermoplastic wire is heated and fed into a coil forming apparatus having a rotative drum holding an injection nozzle so that it registers with and be linked in a common rotative movement to a threaded mandrel also supported by the drum. The wire discharged by the nozzle slidably engages the threads of the mandrel into a helical pattern, the mandrel being radially and coaxially surrounded by a cooled sleeve. The wire will thus solidify along the helical thread of the mandrel, to form a continuous plastic coil being discharged at the downstream extremity of the mandrel and sleeve assembly. Due to the fact that the drum, mandrel and nozzle all rotate in a common rotative movement, it is possible to select the direction and speed of rotation of the three last-mentioned elements so that the coil being discharged have an ouput discharge translational speed, while being exempt of any absolute rotational movement about its longitudinal axis.

Abstract: The invention concerns an ejector for a discharging device for the removal of preforms which enables a partially cooled preform to be detached safely from a form tool and, on complete cooling, to be likewise removed from the discharging device safely and completely.

Abstract: The invention relates to a process for the combustion of a fuel in a burner (1) of the type comprising at least one injector (2), which injector includes at least an inner first oxidizer feed passage (8), an intermediate fuel feed passage (9) externally surrounding the first oxidizer feed passage, and an outer second oxidizer feed passage (10) externally surrounding the fuel feed passage. The fuel feed passage (9) is supplied so that the velocity of the fuel exiting this passage is between approximately 1 and 15 m/s. Application to the supply of heat in processes for the production of materials.

Abstract: A radiant tube burner assembly and method is provided to reduce nitrous oxides and carbon monoxide emissions in the combustion of hydrocarbon fuels. The burner assembly comprises a burner section, exhaust section, radiant tube, plenum and a jet pump assembly. A volume of exhaust gas drawn from the stream of exhaust gases into the jet pump assembly by way of a motive gas is flowed into a stream of combustion air so as to vitiate the oxygen content of the combustion mixture. When the combustion mixture is combusted with fuel in the burner section, the production of nitrous oxides and other harmful emission is mitigated.

Abstract: The invention relates to a process for combustion of a fuel with an oxygen-rich oxidant, in a combustion chamber (3), in which, cyclically: at least one principal variable representing the combustion in the said combustion chamber (3) is measured, and, as a function of the result of the measurement of the at least one principal variable, a control instruction for regulating the flowrates of fuel and oxidant to be injected into the combustion chamber (3) is determined. Then the regulating control instruction is applied in order to make the fuel burn with the oxidant in the chamber (3). Additionally at least one secondary variable associated with an operational constraint of the combustion chamber (3) or with a perturbation in the operation of the latter is measured, and for the determination of regulating control instruction, the measurement result of the at least one secondary variable is also taken into account. The invention is useful in glass furnaces, rotary furnaces, and incineration furnaces.

Abstract: A piezoelectrically-ignited gas appliance comprises a fuel regulator assembly, a burner assembly attached to the fuel regulator assembly, and a piezoelectric ignition assembly partially within the burner assembly. The burner assembly includes a transfer pipe assembly, an air/fuel mixing assembly, and a combustion assembly. The transfer pipe assembly has a proximal end attached to the air/fuel mixing assembly and a distal end attached to the combustion assembly. The an air/fuel mixing assembly has an air opening formed at the proximal end and a fuel injector formed within the proximal end and in fluid communication with the fuel regulator assembly. The combustion assembly has a combustion nozzle and combustion flange attached to the distal end. The piezoelectric ignition assembly includes an piezoelectric charge generator coupled by a thermally and electrically-insulated, semi-rigid conductive wire within the transfer pipe assembly to an electrode.

Abstract: A new infrared heater containing a gas fired burner having a metallic burner body with a combustion plenum chamber, a matrix which covers the combustion mixture plenum and a screen made of fibers treated with a silicon carbide. The screen could be connected to the matrix by a pressure fit. The invention also relates to a new matrix that is energy efficient and made from fibers ceramic or metallic, treated with a pre-ceramic polymer containing silicon and carbon to rigidize the matrix and increase its emittance. The matrix could also have a variety of surfaces that are also more efficient.

Abstract: A burner nozzle includes a burner tube that extends along a central axis and has an inlet end portion for receiving combustible gas and air. At least one body or chamber has a passageway in communication with the burner tube along the central axis which leads to an elongated outlet end portion. At least one flame-shaping opening is located adjacent the outlet end portion. Each flame-shaping opening may be constructed and arranged effective to elongate (broaden the width of) flame resulting from combustion of the mixture transverse to the central axis to produce efficient heat transfer between the flame and air inside a heat-receiving member disposed downstream of the outlet opening. A flame length reducing member may be used instead of or in addition to the flame-shaping opening and the flame shaping opening may itself reduce flame length. A burner assembly may include a combustion tube in which the burner nozzle is disposed and connected.

Abstract: A continuous heat treatment furnace having one of a plurality of furnace zones except for first and last zones as a rapid cooling zone 11 for rapidly cooling a material by blowing an atmospheric gas, which comprises a roll-sealed chamber 3 partitioned at the inlet by first and second roll sealing devices 4A and 4B from the upstream and a third roll sealing device 4C at the outlet as sealing means for atmospheric gas, and in which the inlet of the first roll sealing device and the outlet of the third roll sealing device are connected, and/or the roll-sealed chamber and an uppermost stream portion 6 in the rapid cooling zone are connected, and in which the hydrogen concentration in the furnace is controlled to 10% or higher in the rapid cooling zone and is controlled to 10% or lower in the furnace zone at the inlet of the rapid cooling zone.

Abstract: This invention is directed to a plastic orthodontic appliance having projections extending outwardly from a bonding base. The projections include broadened outer extremities and undercuts proximate the outer extremities which form mechanical bonds with a bonding adhesive. The projections have peened free ends that form the undercuts, preferably with minute fractures therein extending into the outer extremities of the projections. In one application, a plurality of appliances in the form of slotted brackets is provided for cooperating with an archwire to apply corrective forces to a patient's teeth on which the brackets are mounted. Another aspect of the invention concerns a method of making plastic orthodontic appliances suitable for mechanical bonding.

Abstract: An orthodontic device includes a wire member and a fixing member. The wire member consists of on arch wire fixed through concatenation with a tooth and an engaging part fixed at positions corresponding to the points of fixation of the arch wire. The fixing member 2 fixed on the tooth is provided with a mounting groove for mounting the engaging part.

Abstract: An ultrasonic dental scaler for use with a dental scaler insert having a resonant frequency associated therewith includes a handpiece adapted for removably receiving the dental scaler insert, an energizing coil mounted on the handpiece, whereby the energizing coil substantially surrounds the dental scaler insert. The ultrasonic dental scaler includes a selectively tunable oscillator circuit coupled to the energizing coil and which generates a control signal having an oscillation frequency associated therewith for vibrating the dental scaler insert in response thereto. Specifically, the selectively tunable oscillator circuit includes an automatic tuner for automatically altering the oscillation frequency associated with the control signal to be substantially equivalent to the resonant frequency associated with the dental scaler insert in response to the control signal being fed back thereto.

Abstract: A dental handpiece to releasably retain a workpiece (e.g. a dental bur) that is used to treat the teeth of a patient. The workpiece is clamped within a hollow collet between a pair of flexible clamping fingers having a spring-like memory. A collet actuator is arranged in spaced axial alignment with the collet. Both the collet and collet actuator are surrounded by a cylindrical spindle. An axial pushing force applied to a push-button of the handpiece causes the collet actuator to slide through the spindle towards the collet. A pair of wedge-shaped tips having an angle of approximately 22 degrees are carried by the collet actuator into the hollow collet to stress the pair of flexible clamping fingers thereof Accordingly, the clamping fingers are rotated outwardly and away from one another through a stroke gap so as to be moved into contact with the spindle, whereby the workpiece is released for removal from the collet.

Abstract: The anchorage for dental prosthetics includes a male member which is attachable to a tooth and comprises, in a preferred embodiment, a ball head, and a female member which is attachable to a dental prosthesis. The female member comprises an internal thread and a lamellar insert having a threaded portion for receiving and retaining the ball head, the retention force of the lamellar insert being continuously adjustable by rotation thereof. A female member of this kind with a screwed lamellar insert allows a fine adjustment of the retention of the male member in accordance with the actual conditions.

Abstract: A patient's dental prosthesis (e.g., a prosthesis tooth, crown, veneer, or bridge) is made by acquiring an image of the patient's teeth that contains black and white normalization references. These references are black and white porcelain, for example, that allow software of the invention to determine absolute black and absolute white within the image. The image is then normalized in accordance with the normalization references, which corrects the image for variations in lighting conditions and image source. The normalized image is then standardized by matching the pixels of the normalized image to selected shade standards. The dental prosthesis can then be manufactured by a lab technician by referring to the standardized image. The tooth shade analysis and matching system is also applicable to direct restorations of natural teeth, such as repair of chipped or broken teeth.

Abstract: The present invention is directed to enhancing the accuracy with which tooth restorations are performed, including the manner by which a tooth is prepared and fit with a dental prosthetic. Further, the present invention is directed to reducing the skill dependent tasks associated with tooth restoration, while at the same time, improving the precision with which these procedures are performed. By improving the accuracy of restoration procedures, any need to repeat these procedures for a given patient can be eliminated and patient comfort can be improved.