Abstract: The invention concerns a conical hula seal wherein an inner part of the conical hula seal is closer to a conical hula seal longitudinal axis than an outer part of the conical hula seal, and wherein the conical hula seal extends in a circumferential direction relative to the conical hula seal longitudinal axis. A gas turbine which includes the conical hula seal is also disclosed, along with a method of operating a gas turbine which includes a conical hula seal that seals a gap between a first vane and a picture frame, the method including purging the gap with a cooling fluid.

Abstract: A mid-turbine frame (MTF”) for a jet engine is disclosed and comprises a duct that extends between a high pressure jet engine turbine (“HPT”) and a low pressure jet engine turbine (“LPT”), the duct comprising a plurality of segments that together form an outer annular structure and an inner annular structure, the inner annular structure situated radially inward of the outer annular structure, and/or a plurality of vanes that extend radially outward from the inner annular structure toward the outer annular structure, each vane comprising a channel. Each segment may be coupled to an adjacent segment by a seal.

Abstract: A turbine blade for an aircraft turbomachine including a root, an airfoil and a platform inserted between the airfoil and the root and delimiting a gas circulation flowpath, the platform having two axial ends each forming an angel wing of which at least one has an internal cavity that will be supplied with air from the root of the blade. At least one of the two angel wings is drilled with at least one bleed hole for passage of a bleed flow from the internal cavity that will limit/prevent gas recirculation outside the flowpath.

Abstract: A low-pressure turbine of a jet engine includes: a turbine case; turbine blades rotatable about an axis of the turbine case; and a shroud including a plurality of shroud segments annularly placed along an inner peripheral surface of the turbine case while surrounding the turbine blades. Each shroud segment is provided with a projection and an outward groove. The shroud segment is fixed to the turbine case by allowing the projection to engage with a receiving groove of the turbine case in an axial direction, and allowing the outward groove to engage with an inward projection of the turbine case in a radial direction. The shroud segment is provided with a pressure receiving portion that receives a force to release an engaged state of the outward groove with the inward projection of the turbine case in a step of removing the shroud segment from the turbine case.

Abstract: Aspects of the disclosure are directed to a shaft of an engine of an aircraft, an oil scoop coupled to the shaft, a first portion of a sensor integrated with the oil scoop, and a second portion of the sensor coupled to a structure of the engine. In some embodiments, the first portion of the sensor comprises at least one tooth.

Abstract: A system is provided for a turbine engine. The system includes a rotor assembly and a monitoring system. The rotor assembly includes a plurality of rotor blades connected to a shaft. The monitoring system includes a processing system. This processing system is adapted to receive blade data indicative of a rotational position of at least a first of the rotor blades. The processing system is also adapted to process shaft data with the blade data to provide torque data indicative of a torque to which at least a portion of the rotor assembly is being subjected, where the shaft data is indicative of a rotational position of the shaft.

Abstract: A system and method for controlling the operation of a gas turbine engine supplying power to an aircraft. The engine is controlled according to a reading of an amount of power drawn from the supplied power. The reading is fed directly to a control system, which issues commands for controlling engine parameters comprising an acceleration reference signal, load shedding, variable geometry positioning, and fuel flow. The control system may further issue commands for controlling the amount of power drawn. The control system may further use the reading to monitor the engine's condition.

Abstract: The present invention provides a high quality material for ring rolling. The material includes radially outer and inner peripheral surfaces. In the material, a center of gravity on a half section is located so as to be closer to the outer peripheral surface in contact with a main roll than a center of the half section in a thickness direction, a shape of the half section includes a height reducing portion having a height from a center line dividing the half section into halves in a height direction, this height is gradually reduced toward the inner peripheral surface in contact with a mandrel roll, and the shape is formed in a substantially linear symmetry such that the center line is a symmetric axis. A height of the inner peripheral surface is from 20% to 50% of a maximum height of the material.

Abstract: A stator assembly for a gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, at least one stator vane including a platform, a seal member connected to the platform, and a damper between the platform and the seal member. The damper includes a plurality of first fingers and a plurality of second fingers, which are provided in an alternating arrangement.

Abstract: A heat exchanger apparatus for a gas turbine engine includes: a plurality of heat exchanger pipes, each pipe having first and second ends; wherein the heat exchanger pipes are disposed in a repeating pattern such that each heat exchanger pipe is joined to at least one other heat exchanger pipe.

Abstract: A mounting assembly for assembling a bundle of a compressor is provided. The mounting assembly may include a plurality of biasing members and a mechanical fastener. The plurality of biasing members may be disposed in a recess formed in a first annular body of the bundle, and may be configured to apply a biasing force to a second annular body of the bundle. The mechanical fastener may extend through a mounting flange of the second annular body and the plurality of biasing members. The mechanical fastener may be configured to couple the first annular body with the second annular body such that the first annular body and the second annular body define an axial gap therebetween.

Abstract: The present invention relates to a bypass engine bearing holder (1) that holds an upstream bearing (6) and defines, with said upstream bearing, an oil chamber (100) and an air chamber (200), comprising a frusto-conical portion (11) defining an upstream bearing chamber (160) and a downstream inner chamber (150), and comprises an outer collar (13) connected, by a weld (135), to a flange (15) that extends outward from the frusto-conical portion (11). The outer collar (13) has a sealable gimlet (131) engaging with the upstream bearing (6) such as to seal the oil chamber (100). The bearing holder (1) comprises a plurality of oil recovery ducts (8) leading to the downstream inner chamber (150) and to the upstream bearing chamber (160). The oil recovery ducts (8) lead to the upstream bearing chamber (160), downstream from the weld (135) of the outer collar (13) on the flange (15), the weld (135) of the outer collar (13) being axisymmetric.

Abstract: The invention resides in a bearing device for an exhaust gas turbocharger, comprising a first radial bearing and a second radial bearing configured for the radial support of a shaft of the exhaust gas turbocharger, wherein the first radial bearing comprises a bearing axis extending in alignment with the bearing axis of the second radial bearing which is arranged spaced from the first radial bearing, a third radial bearing with a third bearing axis which is extends parallel to, but at a distance (E) from, the first bearing axis and the second bearing axis is arranged between the first and second radial bearings. The invention resides also in a turbocharger including such a bearing device.

Abstract: A squeeze film damper bearing assembly includes a bearing and a squirrel cage radially outward of and supporting the bearing. The squirrel cage includes a first piston ring groove, a second piston ring groove, and a first pocket connected to the first piston ring groove. The squeeze film damper bearing assembly also includes a first piston ring configured to fit into the first piston ring groove. The first piston ring includes a first end circumferentially spaced apart from a second end and an ear configured to fit into the first pocket to prevent the first piston ring from rotating in the first piston ring groove. The squeeze film damper bearing assembly also includes a second piston ring configured to fit into the second piston ring groove and a stationary housing radially outward of the squirrel cage.

Abstract: Aspects of the disclosure are directed to a system associated with an engine of an aircraft. The system includes a shaft configured with at least one axially-oriented hole, and an oil scoop configured to receive oil and provide the oil to the shaft, wherein the oil scoop is manufactured independently from the shaft, and wherein the oil scoop includes at least one retention mechanism for coupling to the shaft after the at least one axially-oriented hole is created in the shaft.

Abstract: A process of remanufacturing a backplate used in turbochargers is provided and includes using a mask or an anti-bonding agent and a thermal metal spray. The mask or anti-bonding agent protects the portions of the backplate from being sprayed. The thermal metal spray can be sprayed on a sealing surface of the backplate that is worn during use. Once the process is completed, the backplate can be inspected to ensure that it meets or exceeds the manufacturer's original specifications.

Abstract: Pin latch assemblies and cam latch assemblies are disclosed. A pin latch assembly is provided comprising a pin housing at least partially enclosing a pin, an actuating device coupled to the pin, and a retaining feature comprising an aperture.

Abstract: A method of manufacturing a flanged composite component is provided. The method includes coupling a composite structure to s first composite material. The method includes coupling a second composite material to the composite structure and placing a first expansion device within the composite structure. A forming element is coupled to at least one of the first composite material, the composite structure, and the second composite material against the mold. The method includes coupling a pressure element to the forming element to define a space among the mold, the forming element, and the pressure element. The method includes expanding the first expansion device to impart a force to the second composite material to move the second composite material away from the composite structure and into the space to facilitate forming a first flange.

Abstract: A split case for a gas turbine engine includes multiple split case portions defining a turbine engine case section. Each of the split case portions has a first and second axially aligned split flange and a circumferential flange on an axial end. Each of the circumferential flanges includes a thermal expansion relief void.

Abstract: Provided is a heat-collecting-type power generation system capable of maintaining a stable power generation efficiency even if supplied heat varies. The system includes an evaporator that heats and vaporizes a working medium; a displacement-type expander driven by the vaporized working medium; a power generator driven together with the expander; a condenser that cools and condenses the gas-phase working medium sent from the expander; and a circulation pump that draws the condensed liquid-phase working medium, raises pressure and transports the same to the evaporator, wherein the expander includes a plurality of expansion parts that expand the working medium stepwise, and internal volume ratios of the expansion parts are adjusted in a design phase, so that if at least one of a suction pressure and a discharge pressure of the expander varies, an overall thermal insulation efficiency is 70 percent or more, in a range of the variation.

Abstract: The invention relates a combined cycle power plant with a gas turbine, a shaft connecting a compressor to a turbine, and a first generator, a heat recovery steam generator fluidly connected to the exhaust of the gas turbine.

Abstract: A method and system of processing animal waste is disclosed. In a particular embodiment, the method includes transferring animal waste to a gasifier to burn the animal waste, circulating water through a heat exchanger in a flue stack of the gasifier to generate heated water, and pumping the heated water to either an organic Rankine cycle system to generate electricity, a radiant heater, or any combination thereof. In addition, the method includes circulating the heated water through an evaporator of the organic Rankine cycle system to vaporize a refrigerant, and circulating the vaporized refrigerant from the evaporator, through a turbine to generate the electricity. Also, the method includes using a manure spreader to feed the animal waste to the gasifier at a varying feed rate that is based on contemporaneously calculating a British thermal units (BTU) of the animal waste being fed to the gasifier.

Abstract: A supercritical carbon dioxide power generation Brayton cycle system and method that employs an alternate heat recuperation method and apparatus that utilizes switched banks of bead filled tanks to accumulate and recover the thermal energy of the two streams of working fluid in such a way that the variable thermal properties of the supercritical carbon dioxide can be accommodated without significant loss of thermal efficiency.

Abstract: The present invention provides a variable valve mechanism of an internal combustion engine, which includes an input member, an output member, a slider and a variable device. The output member has internal space formed therein and has a first cutout and a second cutout which are formed at two positions separated from each other in the swing direction so as to extend from an outer periphery of the output member to the internal space, and the input member is mounted in the internal space so as to extend through both inner sides of the first and second cutouts, and is brought into contact with inner side surfaces of the cutouts from both sides in the thrust direction, whereby relative displacement of the input member together with the slider in the thrust direction with respect to the output member is restricted at two positions by the first and second cutouts.

Abstract: A washer member disposed in a valve housing of an engine is disclosed. The washer member resiliently supports an injector push member via an elastic member and receives a pair of hydraulic lash adjusters for operating an inlet valve and an outlet valve of a cylinder of the engine. The washer member includes a base portion adapted to abut a support member disposed within the valve housing. The support member defines a clearance with the valve housing to movably dispose the pair of hydraulic lash adjusters within the valve housing. The washer member further includes a side portion extending from the base portion. The side portion is configured to define a lateral movement of the elastic member within a tolerance limit. The side portion is further configured to define a rotational movement of the washer member within a tolerance limit.

Abstract: A camshaft adjusting device including a stator which is connectable to a crankshaft of an internal combustion engine and a rotor which is connectable to a camshaft and rotatably supported with respect to the stator and a locking device for locking the rotor with respect to the stator with a locking slide (2) fixed to the stator or fixed to the rotor and produced by a powder metallurgy process and at least one locking pin lockable in the locking slide (2), in at least one section of a surface edge zone (3) the locking slide (2) having a higher density compared to the density of the base material of the locking slide (2).

Abstract: The valve opening/closing timing control device includes: a driving rotating body; a driven rotating body; a fixed shaft portion; a fluid pressure chamber; a partitioning portion; and a phase control unit for controlling a rotation phase by supplying/discharging pressurized fluid to/from an advancing chamber or a retarding chamber via an inside of the fixed shaft portion. The driven rotating body has: an inner circumferential member with a cylindrical portion, and a coupling plate portion of the camshaft, the cylindrical portion and the coupling plate portion being integrated with each other; and an outer circumferential member provided with the partitioning portion. The outer circumferential member includes the inner circumferential member in a unified manner so as to have the same rotational axis. The inner circumferential member is formed with an iron-based material. The outer circumferential member is formed with a material that is lighter in weight than the iron-based material.

Abstract: A system for lubricating a valve assembly of an engine is disclosed. The system includes a valve bridge having a base portion is disposed on a guide rod. The guide rod is received within a hole defined in the base portion of the valve bridge to define a chamber and to receive lubricant in the chamber. The valve bridge includes an arm that is engaged with a valve stem. The valve bridge includes a passage in fluidly communicating with the chamber and an end of the arm. The system includes a valve disposed around the valve stem and valve stem guide. The valve seal includes a lip member that abuts an outer surface of the valve stem to control a flow of the lubricant from the passage to a gap defined between the valve stem and the valve stem guide.

Abstract: Methods and systems are provided for deactivating a valve actuation mechanism. In one example, a system may include first and second hydraulic galleries for supplying hydraulic fluid to a switchable roller finger follower, and a third hydraulic gallery for promoting the flow of air away from the first hydraulic gallery. The third hydraulic gallery may receive a restricted flow of oil from a hydraulic restrictor incorporated into an annular clearance between a VCT oil control valve and a mating bore within the cylinder head.

Abstract: A valve arrangement for the measured supply of gaseous fuel in internal combustion engines with a plurality of electromagnetically operable control valves of an individual cross-section, with the control valves being embodied as seat valves, allowing the allocation of the valve arrangement to an internal combustion engine, and the valve arrangement comprising a nominal cross-section for providing a predetermined volume flow, with the seat valves being designed such that a sum of the individual cross-sections is at least equivalent to the nominal cross-section, an effective cross-section due to a valve stroke of all seat valves is equivalent to the nominal cross-section, and the effective cross-section is smaller or equivalent to the sum of individual cross-sections.

Abstract: A sliding cam system, having at least one sliding cam, which is arranged in a rotationally fixed but axially displaceable manner on at least one axially fixed base shaft of a reciprocating-piston internal combustion engine in order to form a camshaft, at least one actuating device for moving the sliding cam into different axial positions by at least one actuating pin that can reach into at least one displacement groove on the periphery of the sliding cam. The actuating device has a machine-fixed housing and the displacement groove is formed in a top circle surface of the sliding cam down to a groove base and is helical and has an insertion region, a displacement region having an accelerating flank and a braking flank, and a retraction region for the actuating pin. An extended engagement region is associated with the displacement groove and the extended engagement region at least partially has a material removal from the level of the top circle surface in the direction of the groove base.

Abstract: In a lubricating device of an internal combustion engine having a crank chamber and a transmission chamber, which is arranged in the rear of the crank chamber so as to accommodate therein a gear transmission provided with a main shaft and a pump shaft. The pump shaft is shared by a scavenging pump and a feed pump for feeding oil to a part to be lubricated and to which motive power from the crank shaft is transmittable. An axis of the pump shaft is arranged below an axis of the main shaft. A pump gear located on the pump shaft meshes directly with a primary driven gear, which meshes with a primary drive gear located on the crank shaft so as to form a primary gear reduction mechanism in cooperation with the primary drive gear.

Abstract: There is provided an engine lubricating device with which passage resistance of an oil strainer can be reduced and a support stay for an oil filter is unnecessary. An oil strainer includes an outer cylinder and an inner cylinder, the outer cylinder and the inner cylinder respectively have straight central axes and form inner and outer double cylinders, the outer cylinder has a strainer inlet at a lower end, the inner cylinder has a peripheral wall formed as a filter portion, the oil strainer is led out in an orientation inclined downward from the cylinder block toward an inner bottom portion of an oil pan, an upper end portion of the outer cylinder is fixed to a cylinder block, and an upper end opening portion of the inner cylinder communicates with an oil passage inlet of the cylinder block.

Abstract: An oil pan part for a motor vehicle, in particular a passenger car, with a housing and a balancing shaft arrangement with at least one balancing shaft which is rotatably mounted in the housing in one or more cross members of the housing.

Abstract: A silencer includes conduit with a downstream end portion configured from a tubular member which includes a conduit discharge port extending through a silencer main body and discharges exhaust gas to the outside therethrough. The tubular member includes a resonance communication hole communicating with a resonance chamber and an upstream side communication hole and a downstream side communication hole communicating with a second chamber. A barrier wall serving as a throttle portion for throttling an exhaust path at an intermediate location of the tubular member is provided in the inside of the tubular member and between the upstream side communication hole and the downstream side communication hole.

Abstract: A muffler including an inner pipe through which exhaust gas flows and communication portions formed in a peripheral wall of the inner pipe and including holes that communicate a gas flow path of the inner pipe with a muffling chamber. Each of the communication portions further include an inside deformation portion formed by deforming a portion of the peripheral wall toward the pipe inside, and having a downstream side end portion separated from the peripheral wall; and an outside deformation portion formed by deforming a portion of the peripheral wall adjacent to the downstream side of the inside deformation portion toward the pipe outside, and having a upstream side end portion separated from the peripheral wall. The holes are formed by the downstream side end portion of the inside deformation portion and the upstream side end portion of the outside deformation portion.

Abstract: A muffler for an exhaust system of an internal combustion engine, comprises a housing comprising a shell having an inner wall, an inlet pipe and an outlet pipe, the inlet pipe and the outlet pipe extending into an inner space of the housing, for conveying an exhaust gas stream into and out of the inner space of the housing, at least one baffle arranged in the inner space of the housing, the baffle comprising a baffle plate, the baffle plate having a circumference, and a baffle lip arranged at the circumference of the baffle plate, the baffle lip engaging the inner wall of the shell and having an end portion, wherein the end portion of the baffle lip is curved inwardly away from the inner wall of the shell.

Abstract: An improved power generation container providing improved access and installation and removable of components by using modular components. A self bailing and self-aligning exhaust system is further provided.

Abstract: An exhaust gas treatment system for an advanced humid air turbine system includes: an exhaust gas flow path through which an exhaust gas discharged from a gas turbine system flows; a water recovery unit that is connected to the exhaust gas flow path and that cools the exhaust gas that flows in from the exhaust gas flow path to recover water content contained in the exhaust gas; and a bypass flow path through which part of the exhaust gas from the exhaust gas flow path flows so as to avoid cooling in the water recovery unit. The bypass flow path has a downstream end disposed at a position downstream in a flow direction of the exhaust gas with respect to a zone in which the exhaust gas is cooled in the water recovery unit.

Abstract: An exhaust gas purification filter includes: a honeycomb structure body having partition walls for defining a plurality of cells that extend from an inflow end face to an outflow end face; an inflow side plugging portion; an outflow side plugging portion; and a porous surface trapping layer which is disposed on an inflow surface which is a surface on an inflow cell side which is the cell in which the outflow side plugging portion is disposed, among surfaces of the partition walls, in which the surface trapping layer has a thickness of 10 to 60 ?m and an average pore diameter of 0.3 to 5 ?m, and in a section which is parallel to a cell extending direction.

Abstract: An exhaust system for an internal combustion engine of a motor vehicle, includes an SCR catalytic converter for carrying out selective catalytic reduction of pollutants contained in the exhaust gas of the internal combustion engine using a reducing agent, wherein the SCR catalytic converter is arranged downstream of a turbine of an exhaust gas turbocharger, and a feed device for feeding the reducing agent into the exhaust gas at a feed position arranged upstream of the turbine is provided. A nitrogen oxide storage catalytic converter is arranged upstream of the feed position.

Abstract: There is provided an engine exhaust treatment device in which stick of a nozzle portion of a urea water injector can be suppressed. The engine exhaust treatment device includes: an SCR catalyst case housing an SCR catalyst; an SCR exhaust inlet pipe; and the urea water injector and the nozzle portion of the urea water injector is directed toward an inside of the SCR exhaust inlet pipe. An exhaust deflector is provided in the SCR exhaust inlet pipe and the exhaust deflector is mounted to an inner peripheral face of the SCR exhaust inlet pipe on an exhaust upstream side of the urea water injector so that exhaust flowing toward the nozzle portion of the urea water injector is deflected by the exhaust deflector and diverted from the nozzle portion.

Abstract: An exhaust purification device for an internal combustion engine is provided with an NOx adsorbent for adsorbing NOx in exhaust gas and an NOx purifying catalyst for purifying NOx in exhaust gas, which are arranged in an engine exhaust passage. An electric heater is provided for raising the temperature of the NOx adsorbent. When a signal requesting startup of an internal combustion engine is issued, the device starts to supply electric power to the electric heater before the internal combustion engine completely warms up, and supplies the electric heater with a quantity of electric power making the temperature of the NOx adsorbent equal to or higher than the moisture desorption temperature but lower than the NOx desorption temperature.

Abstract: An aftertreatment system comprises a liquid exhaust reductant tank. A heat exchanger is positioned downstream of the preheater. The heat exchanger heats the liquid exhaust reductant to a second temperature. The second temperature is sufficient to decompose the liquid exhaust reductant and produce ammonia gas. A storage tank is positioned downstream of the heat exchanger and is structured to store the ammonia gas at a predetermined pressure. The aftertreatment system also includes a selective catalytic reduction system positioned downstream of the storage tank. The aftertreatment system can also include a preheater positioned downstream of the liquid exhaust reductant tank and upstream of the heat exchanger.

Abstract: An exhaust gas control apparatus for an internal combustion engine includes a urea water injection valve, a catalyst disposed in an exhaust passage downstream of the injection valve, and an electronic control unit. The injection valve is configured to add urea water to exhaust gas. The catalyst is configured to adsorb ammonia generated from the urea water. The electronic control unit is configured to (i) set a target adsorption amount of the ammonia adsorbed on the catalyst, (ii) control the injection valve such that the amount of the urea water added to the exhaust gas becomes an addition amount calculated based on the target adsorption amount, and (iii) execute an initialization processing for decreasing the amount of the ammonia adsorbed on the catalyst to (zero) when an integrated value of the amount of the NOx flowing into the catalyst is equal to or higher than a predetermined value.

Abstract: A controller calculates a period travel distance that is a travel distance of the vehicle from when the available travel distance is calculated to when the available travel distance is calculated next. The controller, when the remaining amount of urea aqueous solution inside a tank exceeds a predetermined amount, executes a first calculation process in which the available travel distance is calculated with reference to the remaining amount of the urea aqueous solution. The controller, after the remaining amount of the urea aqueous solution becomes smaller than or equal to a predetermined amount, executes a second calculation process in which the available travel distance is calculated by subtracting the period travel distance from the previously calculated available travel distance.

Abstract: A method includes determining whether a urea refill event is detected, and clearing a quality accumulator value and clearing a latching abort command. The method includes determining whether urea fluid quality check abort conditions are met, and clearing the urea quality accumulator, latching the abort command, and exiting the reductant fluid quality check. In response to the abort conditions not being met, incrementing the urea quality accumulator according to an amount of urea being injected, and comparing the accumulated urea quantity to a low test threshold. The method includes, in response to the accumulated urea quantity being greater than the low test threshold, comparing the accumulated urea quantity to a high test threshold, and in response to the urea quantity being greater than the high test threshold, determining whether the a NOx exceedance is observed and clearing a urea quality error in response to the NOx exceedance not being observed.

Abstract: An electrically-heated catalytic converter includes: a substrate made of ceramic, the substrate including a catalyst coated layer; electrode films made of ceramic, the electrode films being disposed on a surface of the substrate; electrode terminals made of ceramic, each of the electrode terminals being secured to a corresponding one of the electrode films; and external electrodes each attached to a corresponding one of the electrode terminals via a brazing filler metal. A thermal expansion coefficient of the brazing filler metal is equal to or higher than a thermal expansion coefficient of the electrode terminals, and is equal to or lower than a thermal expansion coefficient of the external electrodes. The thermal expansion coefficient of each of the electrode terminals decreases from a portion at which the electrode terminal is joined to the brazing filler metal toward a portion at which the electrode terminal is joined to the corresponding electrode film.

Abstract: The present invention relates to an automobile urea tank produced using a forming method. The method includes the following steps: (a) producing an upper half casing and a lower half casing through an injection molding method; (b) after the upper half casing and the lower half casing are formed, assembling built-in parts of the upper half casing and the lower half casing; (c) welding the assembled upper half casing and the assembled lower half casing to form a whole; and (d) assembling components on surfaces of the upper half casing and the lower half casing. This method can improve design freedom of built-in elements of the tank body, and can save a lot of raw materials; the structure is simple and firm; moreover, the production efficiency is improved, and the production cycle is shortened.

Abstract: An external air introduction apparatus includes: an external air introduction opening that guides external air into an exhaust channel, and opened and closed by a pressure difference between an external air pressure and a pressure inside the exhaust channel; a valve plate having a valve body that elastically deforms due to the pressure difference; a base plate stacked on the valve plate and having an opening that faces the valve body and smaller than the valve body and a seat surface formed around the opening; and a restriction plate that restricts elastic deformation of the valve body. The opening is closed and opened by the contact and separation of the valve body and the seat surface. The plates are fixed to a wall that forms the exhaust channel with a fastening member.