Abstract: The invention relates to an electromechanical actuating drive for a valve, in particular of a steam turbine. It has a push rod for setting an opening position of the valve and also an electric motor for driving the push rod. The push rod is connected to the electric motor via a transmission device which generates a changing torque, depending on the axial displacement of the push rod. The invention relates, furthermore, to a steam turbine.

Abstract: A helical flow compressor used to supply gaseous fuel to a turbogenerator is equipped with an inlet throttling valve. The inlet throttling valve maintains the outlet pressure of the compressor at a preselected value.

Abstract: An intake and exhaust damper assembly has a motor and fan assembly pivotally mounted for movement toward and away from a louvered rotatable blade damper.

Abstract: A ventilation module optimized as to size, accessibility and air circulation, including an motorized fan unit (MFU) (2) for at least one suction turbine (16), a shell housing (15) accommodating the turbine (16) driven in rotation by an electric motor about a central rotational axis (Z′Z), the shell (15) being coupled to at least one air intake (11, 12) and outlet (13) formed in an outer casing (10), the incoming air being sucked in by the turbine (16) through at least one central orifice (&OHgr;1, &OHgr;2) formed in the shell (15). An air-inlet flap (17) extends on either side of the shell (15) and is driven in rotation by actuating means about an axis parallel to the rotational axis (Z′Z) of the turbine (16).

Abstract: A steam turbine includes a turbine casing, in which a turbine rotor is accommodated so as to extend along a direction of flow of steam, and a plurality of turbine pressure sections are mounted to the turbine rotor, which includes, in combination, at least two or more of a turbine high pressure portion, a turbine intermediate pressure portion and a turbine low pressure portion. The turbine casing is divided into two casing sections, each of the divided turbine casing sections being further divided into a turbine casing upper half and a turbine casing lower half, and the turbine casing lower halves of the divided turbine casing sections being connected to each other by a fastening member such as stud bolt inserted from a side of the turbine low pressure portion.

Abstract: An air compressor includes a housing having a port formed in a motor casing and another port formed in a fan casing. The fan casing has a mouth for air to flow into the housing. The mouth may be selectively blocked for facilitating the drawing of the air into the housing via the ports. The fan device includes a plate having two sides and having one or more blades extended from each of the sides of the plate for facilitating the air circulating or paddling or drawing effect of the air compressor. The blade is preferably extended radially and laterally relative to the plate.

Abstract: Nozzle control apparatus for an axial flow air turbine having an inlet nozzle for air entering the turbine and an associated turbine inlet housing for channeling air flowing to the inlet nozzle for at least partially blocking air flow from the turbine inlet housing to the turbine inlet nozzle. The nozzle control apparatus uses an axially movable annular slider member that is biased to its open position by an annular spring and is moved axially by bleed air pressure exerted on a portion of the annular slider member.

Abstract: In an exhaust turbocharger for an internal combustion engine including a turbine and a compressor, which is driven by the turbine, wherein the compressor comprises a compressor impeller in a flow duct, a transfer component with flow passages extends radially around the compressor impeller in the axial direction of the impeller and provides for communication with the flow duct. To provide for variable adjustment of the effective flow cross-section of the transfer duct, a transfer ring is provided which comprises two component rings, which are rotatable relative to one another.

Abstract: A portable generating system for converting either water or wind energy into electricity comprises a paddle wheel assembly having a housing and a plurality of impellers rotatably mounted therein. The housing defines inlet and outlet openings for receiving a fluid stream, whether water or air, therebetween so as to rotate the impellers. The impellers are axially connected to a generator for producing electricity upon impeller rotation as the fluid stream flows between the housing openings. The generator may be mounted within the paddle wheel housing adjacent the impellers or at a distance therefrom and coupled thereto with a shaft. A plurality of mounting brackets are fixedly attached to the outer surface of the housing. The generating system further includes a plurality of height-adjustable support legs that may be coupled to the mounting brackets so that the paddle wheel housing may be positioned at a predetermined height above a support surface.

Abstract: Water is first caused to flow through a first passage and rotate a first impeller. Rotation of the first impeller is linked to rotation of a second impeller, which is in fluid communication with a second, discrete passage. Vanes on the second impeller are constrained to move faster than vanes on the first impeller. Water is subsequently caused to flow through the second passage and to be more aggressively advanced by the second impeller.

Abstract: In an engine braking arrangement for an internal combustion engine with an exhaust gas turbocharger including a turbine arranged in the engine exhaust duct and a compressor driven by the turbine and arranged in the engine intake duct, a brake valve disposed in the exhaust duct upstream of the turbine and a pressure relief line extending from the exhaust duct upstream of the turbine rotor to an area downstream of the turbine and including a stop valve, the stop valve is a rotationally adjustable rotary valve operable by an actuating device depending on the intake pressure in the intake duct.

Abstract: A turbomolecular pump comprising a rotor and a stator housed in a casing and an exhaust mechanism is formed between the rotor and the stator; wherein the turbomolecular pump has a valve body for opening and closing a suction port provided in the casing, and a valve driving mechanism for opening/closing-driving the valve body, wherein the valve driving mechanism is provided integrally with the turbomolecular pump.

Abstract: A method for forming a pulsating air pattern at a surface of an electronic carrier assembly. The electronic carrier assembly includes a circuit card having an attached module or chip. An air circulation pattern, or flow pattern, is formed at the surface of an electronic carrier assembly by natural convection, or by a steady air flow generated by a fan, respectively. A suitably-positioned rotatable disk having one or more void regions, and in a state of rotation, interrupts the air circulation or flow pattern by causing a pulsation air pattern at the surface of the electronic carrier assembly. The effect of the pulsating air pattern is to increase the rate of heat transfer from the electronic carrier assembly by two mechanisms. First, the thickness of the boundary layer at the surface of the electronic carrier is reduced, thereby increasing the heat transfer coefficient at the boundary layer. Second, stagnant air trapped between nearby electronic components on the electronic carrier assembly is swept away.

Abstract: A blower unit includes a case divided into an upper case portion having an air introduction port, a lower case portion for accommodating a fan, and a bell-mouth portion interposed between the upper and lower case portion portions. An air leading port is provided in the bell-mouth portion, so that air sucked from the air introduction port is introduced to the fan through the air leading port. An attachment boss portion onto which a motor is attached is formed to protrude from an outer wall surface of the upper case portion. Air blown by the fan flows through a duct which is divided into a first member integrated with the bell mouth portion and a second member integrated with the lower case portion. The first member extends from the bell mouth portion obliquely to cover the attachment portion, and the second member extends from the lower case portion in the same direction as the first member to be engaged with the first member.

Abstract: A turbo-machine having a means for attaching the blade ring to the casing at a plurality of alternative radial positions to provide for a plurality of alternative clocking angles for a stage of stationary airfoils. The blade ring is provided with a plurality of notches that may selectively be aligned with a pin inserted through the casing. By rotating the blade ring so that a selected notch aligns with the pin, a selected clocking position may be achieved. Assembly with a different clocking angle is achieved by aligning the pin with a different notch. The notches may be provided at any location around the blade ring so long as they are separated by a radial distance which is a non-integer multiple of the segment angle.

Abstract: The method enables a turbine to be used at varying speeds and powers. An injector (15) is placed in a channel (3) downstream from a turbine (4); it creates a Venturi effect and converts pressure control into control of the mass flow rate of a mixed fluid. Sensors (18) and a regulator (17) enable the speed of the turbine (4) to be matched to a reference speed. A variant consists in placing a suction generator at the outlet of the section (5) of the channel (3).

Abstract: A method for fabricating a turbine inlet casing has several steps. Providing a prismatic block having an upstream face, a downstream face, and a central axis perpendicular to the upstream and downstream faces. Cutting a circular shaft clearance opening through the block, concentric with the central axis. Cutting an inlet plenum through the block along the central axis. The inlet plenum is positioned towards an outer edge of the block. Cutting one or more distribution ports through the block along the central axis. These ports begin close to the inlet plenum and end at annular segments which are concentric with the central axis and at a radial position coincident with the turbine flowpath. The annular ends (of the distribution ports) are spaced circumferentially apart from each other. Cover plates are attached to the upstream and/or downstream faces of the block over the passages and ports. Connecting holes are made between the inlet plenum and the distribution ports.

Abstract: A turbomolecular pump evacuates gas in an apparatus (or a chamber) by means of a rotor having blades and/or spiral grooves which rotates at a high speed. The turbomolecular pump includes a casing housing a rotor and a stator therein, a pumping section comprising the rotor and the stator, a valve element capable of opening or closing an intake port of the casing, and a supporting member for supporting the valve element. The supporting member extends through at least one of the rotor and the stator. The turbomolecular pump further includes an actuating mechanism for actuating the valve element, and the actuating mechanism is provided at a side opposite to the intake port with respect to the rotor.

Abstract: An improved air inlet cover and impeller for a convertible electric blower/vacuum. The blower/vac includes an electric motor which drives an impeller. A plurality of blades located on the impeller define a frusto-conical surface of revolution. The air inlet cover includes an integral, frusto-conical pressure ring which is located offset but generally congruent to the surface of revolution defined by the impeller blades. The cover additionally includes an air grate that allows the passage of air but prevents the passage of other objects. The grate also includes a choke member for adjusting the effective area of the air inlet into the blower/vac to control the exit air volume and velocity of the blower. The cover also includes a bell-mouthed opening integral with the choke member to increase the efficiency of the blower/vac when in the blower mode.

Abstract: An inlet guide vane assembly for a centrifugal compressor includes a guide vane housing having an inlet side for receiving a fluid passing through the compressor at a first flow angle, an outlet side remote from the inlet side and a central axis extending between the inlet and outlet sides of the housing. The assembly has a first set of inlet guide vanes pivotally mounted within the guide vane housing, between the inlet side and the outlet side thereof, for impinging upon the fluid passing through the housing. The assembly includes a second set of inlet guide vanes pivotally mounted within the guide vane housing, between the first set of inlet guide vanes and the outlet side of the housing, for impinging upon the fluid passing through the housing after the fluid has passed through the first set of inlet guide vanes.

Abstract: A method and apparatus for regulating fluid flow through a turbine comprising a valve housing positioned in a fluid flow path, the valve housing having a fluid inlet, a fluid outlet, and chamber connecting the fluid inlet and the fluid outlet; a valve sleeve positioned within the chamber, the sleeve comprising a wall having inner and outer surfaces with a plurality of preferably peripherally spaced ports positioned around the periphery of the sleeve, the ports extending between the inner and outer surfaces; a valve head having first and second ends and at least two seal rings with at least one seal ring proximate the first and second ends respectively, the head dimensioned to fit tightly and move reciprocatively within the sleeve; a valve stem having a first and second end, wherein the first end is attached to the valve head, the stem extending away from the valve head; and an actuator attached to the second end of the valve stem.

Abstract: A ring support system for use in a variable pipe diffuser. The ring support mechanism includes at least three axle shafts and at least three roller bearings rotatably mounted to the axle shafts, an inner ring having a groove disposed in the outside diameter, and an outer ring having a corresponding groove disposed in the inside diameter. The at least three axle shafts are circumferentially mounted in the outer ring such that the rollers are positioned partially within the groove of the outer cylinder such that the roller bearings define a diameter nearly equal to the outside diameter of the inner ring. The inner ring is positioned within the at least three roller bearings such that the at least three roller bearings are in axial sliding contact with the groove of the inner ring and in rolling contact with the groove of the inner ring. The ring support system provides rotational and axial support of the inner ring.

Abstract: A high degree efficiency in a gas turbine is assured by imposing a rifling swirl on the operating medium. The gas turbine has a turbine shaft and a number of burners that discharge into a combustion chamber configuration. The primary burner axis of each burner is tilted relative to the primary axis of the turbine shaft such that a defined swirl is created in the operating medium. An especially effective transfer of momentum from the flowing operating medium AM to a rotor blade configuration, particularly in full-load operation of the gas turbine, is thus attained without additional structural parts between the combustion chamber configuration and the rotor blade configuration.

Abstract: A pump having a three-way valve has a motor for generating a turning effect by an electric power applied thereto. The pump pressurizes a fluid by using an impeller. The three-way valve is installed to the inlet side of the pump. A magnetic plate and ball swing between the first inlet and second inlet by means of load switches as many as a predetermined angle. The pump and three-way valve are integrally formed to require no separate piping between the three-way valve and pump. Thus, the manufacturing processing of the boiler is reduced while enhancing productivity. An installation space is shrunken to decrease the external dimensions of a product such as boilers.

Abstract: A turbocharger in which a turbine wheel located in a turbine chamber is driven by an exhaust gas flow. A bypass passageway extends around the chamber to enable exhaust gas to be diverted away from the turbine wheel. A valve is mounted in the bypass passageway and controlled so as to selectively open and close the passageway. The passageway opens into the exhaust gas outlet in a direction such that gas issuing from the passageway is directed in a substantially annular form and in a substantially downstream direction.

Abstract: The present invention provides an air box throttle assembly for improved characterization of a combustion system in which an arrangement of three air shutters is used to maintain a fairly constant air to fuel ratio as the combustion system is driven from low fire to high fire. A high fire shutter and a main air shutter each comprise two vanes and are rotatably mounted within an air intake box for a combustion system. A low fire shutter is provided with a single vane and is fixed above the main air shutter. The high fire shutter is the principal regulator of large volumes of air entering the combustion system when operating at high fire. At high fire, the main air shutter is fully open and low fire shutter has little effect on the flow of air through the air intake box. Low fire shutter is the principal regulator of small volumes of air entering the combustion system when operating at low fire.

Abstract: The invention provides a regulating system (23) for controlling the heating of the gases on the downstream side of the regulating system, attenuating the aerodynamic noise produced by the gyratory flow on the downstream side of the directing vanes (24) of the regulating system and facilitating the endoscopic inspection of the blades and vanes of a compressor (3) owing to the provision of a throughway passage (27) in the regulating system (23), and in particular a throughway opening in at least one directing vane (24).

Abstract: A method and an apparatus for generating a pulsating air by communicating an air passage intermittently by rotating a valve while feeding air into a casing or discharging air from the casing by a blower connected to a connecting port of the casing. The air passage extends from the connecting port for the blower to a transmitting port of the casing for transmitting a pulsating air. The apparatus for generating a pulsating air is comprised of a casing provided with a connecting port for a blower and a transmitting port for a pulsating air. The connecting port for the blower is connected with a feeding side of the blower or a suction side of the blower. The valve is designed to be operated so as to intermittently communicate the air passage.

Abstract: The axial gap (30) between a turbofan section (18) in a turbofan aircraft engine (10) is enlarged so that foreign matter thrown radially outwardly by the fan blades (48) will travel vectors (52, 54) which are located forwardly of the forward boundary (28) of the splitter wall (26). This results in the foreign matter being expelled through the fan duct (14) the engine (10), preventing it from entering into the engine core (20). Forward extensions (56, 58) of the fan blades can also be used for shifting the vectors (52, 54) forwardly. Smaller forward extensions (56, 58) can be used in combination with a partially widened gap (30) for positioning the vectors (52, 54) forwardly of the splitter wall forward boundary (28).

Abstract: A rotary separator turbine having inlet structure for mixtures of gas and liquid, rotary shaft structure comprising separator structure to receive the mixture of gas and liquid and to separate the mixture into a stream of gas and at a stream of liquid; first structure to receive the stream of gas for generating torque exerted on the shaft structure, and; second structure to receive the stream of liquid for generating torque exerted on the shaft structure; whereby the first and second structure separately operate to generate shaft power.

Abstract: Linear electric actuators powered by DC brushless servomotors are individually controlled to position steam turbine valves by way of levers, pins and links to thus eliminate hydraulics and the attendant disadvantages of fluid filtering, conditioning and leakage as well as obtaining more flexible individual valve control, vis-a-vis, camshaft operated hydraulic actuators. Additionally, low friction actuators and springs are employed to automatically close the turbine valves in the event of a power failure.

Abstract: An arrangement for controlled admission to a nozzle assembly of axial flow extraction steam turbines consists essentially of a control valve located upstream of the nozzle assembly and having two inlet windows for the working medium and of a duct element located between the control valve and the nozzle assembly. The duct element is provided with a plurality of inlet flow ducts which connect the inlet windows of the control valve to the nozzles of the nozzle assembly. The control valve is rotatable by 180.degree. in the peripheral direction for increasing the opening or closing of the inlet flow ducts.

Abstract: An axial-flow blower of stator vane controllable pitch type has an upstream-side opening of an air separator on the upstream side of a controllable pitch type inlet guide vane so that the recirculating flow in the air separator can be joined smoothly with the axial main flow irrespective of the set angle of controllable pitch angle.

Abstract: A vertical centrifugal hydraulic pump assembly is provided fitted with at least one replaceable pack incorporating the centrifugal hydraulic elements of the pump, the pack being clamped between two flanged end plates and mounted vertically in a receiving bore of a pump body, the base region of the receiving bore housing a flat annular non-return valve fitted between the inner wall of the bore and the outer wall of a central inlet connector, the valve opening in the direction of delivery of the pump.

Abstract: A diverter for a divided volute turbocharger has a rotatable diverter member in one volute passageway of the turbocharger. The diverter member is rotatable between a first position in which the flow of gas through the associated volute passageway is unimpeded by the diverter member, and a second position in which the diverter member blocks the associated volute passageway and causes the gas from that passageway to flow through an interconnection passageway into the other volute passageway. If desired, the diverter member may block the interconnection passageway while the diverter member is in the first position.

Abstract: A method of controlling a centrifugal compressor having a variable width diffuser section, the compressor being part of a chiller having a condenser and an evaporator, the method including the steps of defining the width of the diffuser which results in an optimum noise and performance level at given values of an operational parameter of the compressor, periodically sensing the operational parameter of the compressor, and periodically varying the diffuser width according to the sensed operational parameter to create a diffuser width that results in the optimum noise and performance levels at the sensed value of the operational parameter. The step of defining preferably defines the width based at least on the capacity at which the compressor is operating. The capacity is preferably determined by measuring the flow and temperature difference of the fluid passing through the evaporator. A control system for controlling the chiller system to minimize noise is also disclosed.

Abstract: A diffuser of a centrifugal compressor for guiding a fluid flowing from an impeller to a scroll. The diffuser is formed by a pair of oppositely disposed lateral walls. The diffuser is provided at a fluid outlet portion thereof with an outlet throttling portion. This outlet throttling portion is formed by gradually narrowing the passage width downstream from a starting point which is located in a position at which the fluid dynamic pressure is almost perfectly changed to a static pressure. The provision of the outlet throttling portion decreases the risk of a pressure loss, restrains the possibility of flow separation and prevents the fluid from reversely flowing from the scroll. This results in improvements in surge line and partial load efficiency.

Abstract: A steam turbine control valve actuator for lever-operated control valves includes a servomechanical actuator with a reciprocable rod. Such servomechanical actuator is mounted upon a support assembly that is, in turn, pivotably mounted to the control valve body. A distal end of the rod is coupled by a knuckle joint to one end of the lever which operates the control valve, and forces of the rod are biased by a spring that substantially eliminates side forces on the rod through maintenance of the effort that is applied to the lever by the rod in a direction that is parallel to the rod.

Abstract: A twin wastegate valve for an exhaust gas driven turbocharger in which exhaust gas is communicated to the turbine wheel through separate inlet passages includes a pair of wastegate valve members mounted for pivoting movement relative to a support. The support is pivotally mounted on the actuating arm. Accordingly, small differences in the height of the valve seat caused by wear or by manufacturing tolerances do not affect closure of the valve.

Abstract: The expense of variable inlet guide vane structure for rotary compressors is avoided in a structure including a compressor housing 20 with an inlet end 24 and a rotor 10 journaled within the housing 20 by disposing a housing 42 about the inlet end 24 and having an inlet port 54 over a minor fraction of its periphery. A single guide vane 60, is disposed within the inlet port 54 to impart preswirl to incoming air as it enters the housing 42.

Abstract: A variable geometry turbine in which an inlet passageway has a movable wall the position of which is adjusted to match the turbine characteristics to the flow rate through the turbine. Nozzle vanes extend through the movable wall and are mounted on a nozzle support which is normally stationary so that the nozzles contact the facing wall of the inlet passageway. The nozzle support is arranged to move with the movable wall however when the movable wall opens the inlet passageway beyond a predetermined extent so that the nozzle vanes are at least partially retracted when the movable wall is in the fully open position.

Abstract: A variable-capacity exhaust gas turbine supercharger comprises a radial turbine and a compressor driven by the turbine. The turbine has a scroll portion divided into an open scroll chamber and a closed scroll chamber. The open scroll chamber directly communicates with an engine manifold and has a nozzle portion facing circumferential portions of turbine blades. The closed scroll chamber communicates with the engine manifold via a change-over valve and has an annular opening opened to rear portions of the turbine blades, and a nozzle portion having a plurality of gas passages defined by stationary guide vanes is provided between the annular opening of the second scroll chamber and the rear portion of the turbine blades.

Abstract: A radial turbine of a variable area nozzle type which is suitable for use as the exhaust turbine of a turbocharger for an automotive internal combustion engine requiring a quick response and a wide operating range. This turbine comprises at least two groups of variable area nozzles which may be, for instance, defined by moveable vanes, and can be individually controlled for each group to vary their sizes. By opening the variable area nozzles of the first group while the variable area nozzles of the second group are kept closed, a sufficient supercharging effect can be obtained even when the fluid flow rate is small. By opening the variable area nozzles of both the groups, the resistance to the fluid flow can be reduced and the creation of excessive back pressure at the inlet to the turbine can be avoided even when the fluid flow rate is large. In this way, not only the operating range of the turbine can be expanded but also the control accuracy particularly in small nozzle opening condition can be improved.

Abstract: A splitter vane/shut-off valve system for use in a centrifugal pump which includes an impeller and an inlet to the impeller. A plurality of planar, anti-swirl vanes are arranged in a cross-configuration across the inlet adjacent the impeller to straighten the flow of fluid to the impeller and to prevent swirling of the fluid by the impeller. Edges of the planar vanes, facing the incoming fluid, define a valve seat. A plurality of petal valves are pivotally mounted at pivot points to the side of the inlet and movable toward and away from the center of the inlet. The petal valves engage the valve seat defined by the edges of the planar vanes for closing the inlet to allow removal of the impeller.

Abstract: The present invention relates to a combination of a Savonius type rotor (20) and a deflector plate device (101) which serves as an augmentation apparatus which considerably increases the power output of the Savonius type rotor and also improves its self-starting ability and smoothness of operation. The invention also describes a novel Savonius type rotor (20) of greater efficiency than existing Savonius type rotors. In connection with the rotor-deflector combination, the present invention also teaches a simple, automatic speed control mechanism (107) which additionally can be used to facilitate stopping the rotor if desired.

Abstract: A cartridge or plug-in pump for use in a fluid holding receptacle such as an aircraft fuel tank. A pump housing on the fluid holding receptacle has an inlet opening to allow passage of fluid from the receptacle into the pump housing. A plug-in pump assembly is axially and rotatably positionable in the pump housing. A pump inlet closure is mounted on the pump housing for movement between inlet open and closed postions. Seals are provided between the pump housing and the pump assembly. A first actuator moves the closure to its inlet closed position in response to rotational movement of the pump assembly relative to the pump housing. A second actuator moves the pump assembly axially relative to the pump housing to break the seals also in response to rotational movement of the pump assembly relative to the pump housing. The first and second actuators are synchronized whereby the closure is in its inlet closed position at the time the seals are broken.

Abstract: A variable capacity radial flow turbine includes a turbine housing which incorporates a turbine wheel and which forms a working gas passageway that leads to the turbine wheel and that is divided into two parts. The working gas passageway is provided with a pivotable plate-like member, so that the flow rate of the working gas flowing into the turbine wheel can be continuously changed by shifting the position of this member and thus opening or closing part of a working gas intake.

Abstract: A turbo-supercharger for an engine including a turbine casing of which scroll is formed with two exhaust gas inlet passages. The turbine casing has an inlet end surface connected with the outlet end surface of an engine exhaust pipe. The inlet passages are opened to the inlet end surface of the turbine casing respectively through inlet ports which are arranged in side-by-side relationship. A valve mechanism is provided to close one of the inlet ports under a low speed engine operation. The valve mechanism has a valve member adapted to seat on the inlet end surface and a swingable arm mounted on the exhaust pipe for moving the valve member. The exhaust pipe is formed with a sidewardly bulged portion where the swingable arm is supported. The swingable arm and the valve member are substantially received in the bulged portion in the open position.

Abstract: A turbine, particularly for a sprinkler system, comprises a rotor mounted on a shaft so as to be rotatable about a rotor axis and having a plurality of curved vanes attached to the wheel rim, a variable nozzle and a control device for control of the flow of water through the turbine. The control device is mounted in a ring shaped space, is a part of the nozzle and a part of the wall of the ring shaped space and the control device controls the size of both an annular clearance between the turbine wheel and the control device and the cross section of the nozzle so that the cross section of the nozzle and the annular clearance are correlated with each other. Advantageously the control device may be a broad surface curved plate mounted on a pivot shaft so as to be pivotable partly between two parallel walls of a fixed part of the nozzle formed by the turbine housing and shaped to follow the radius of curvature of the outer periphery of the rotor.

Abstract: A turbocharger driven by exhaust gases of an internal combustion engine wherein a scroll is split into two sections extending side by side in parallel to the direction of flow of the exhaust gases. A control valve for controlling the inflow of exhaust gases into at least one of the two sections of the scroll is provided, and a valve seat structure cooperating with the control valve is formed separately from a turbine casing and secured in place between an inlet portion of the turbocharger and an exhaust passageway of the engine.