Abstract: Apparatuses, methods, and systems directed to efficient cooling of data centers. Some embodiments of the invention allow encapsulation of cold rows through an enclosure and allow one or more fans to draw cold air from the cold row encapsulation structure to cool servers installed on the server racks. In other particular embodiments, the systems disclosed can be used to mix outside cool air into the cold row encapsulation structure to cool the servers. In some embodiments, the present invention involves fanless servers installed on the server racks and introduces fan units to draw cooling air from the cold row encapsulation structure through the fanless servers on the racks.

Abstract: According to one embodiment, an electronic apparatus includes a housing, a partition, a first cooling fan, and a second cooling fan. The partition partitions an inside of the housing into a first chamber and a second chamber. The first chamber communicates with a first inlet, a third inlet, and a first outlet. The second chamber communicates with a second inlet and a second outlet. The first cooling fan locates above the third inlet in the first chamber, and includes a first intake configured to draw air in the first chamber, and a second intake configured to draw air outside the housing through the third inlet, the first cooling fan being configured to discharge the air to a heat sink. The second cooling fan locates in the second chamber and is configured to draw air in the second chamber, and to discharge the air to the second outlet.

Abstract: A server and cooler module arrangement includes a server accommodating a stack of an operating system and an electronic device in an accommodation chamber therein at one side and an access device unit in the accommodation chamber at an opposite side, and a cooler module, which comprises a rack mounted in a partition way in the accommodation chamber between the stack of operating system and electronic device and the access device unit and a plurality of fans respectively adjustably mounted in respective open frames at different elevations and adapted for drawing air or sending air toward different heat sources in the operating system, the electronic device and the access device unit for quick dissipation of waste heat.

Abstract: A display unit is disclosed. A display apparatus includes a panel unit displaying images, a circuit unit provided a rear surface of the panel unit, a chamber surrounding the circuit unit, the chamber forming a predetermined space and at least one ventilation fan ventilating air inside the chamber along a circulation path passing beyond the circuit unit. According to a display apparatus according to the present invention, parts which are mounted in the display apparatus may be protected from external moisture or dust. Furthermore, heat radiation may be performed efficiently in the display apparatus according to the present invention even if environments of heat exchanging with an outside may not be formed enough in a structure of the display apparatus.

Abstract: A heat sink with a centrifugal fan comprising: a cover of a prescribed shape including an air intake port and an air discharge port; a heat receiving block thermally connected to a heat generating part to be cooled; a bottom portion which is excellent in heat transferability, thermally connected to one face of said heat receiving block, and engaged to said cover to form a space portion; a heat dissipating fin portion comprising a plurality of fins, received within the space portion, thermally connected to said bottom portion, and having a prescribed shape including at least an air inflow portion; and a centrifugal fan, a rotating shaft of which is arranged in a vicinity of the air inflow portion of said heat dissipating fin portion, which intakes air from the air intake port, generates an air flow through spaces formed between adjacent fins of said heat dissipating fin portion, and generates another air flow along an inner wall of said cover toward said air discharge port.

Abstract: A fan module is disposed in an electrical device. The electrical device has a main board and a casing. The fan module includes a vane module, a fan motor, a circuit board and a fan housing. The vane module has a hub and a plurality of vanes disposed around the edge of the hub. The fan motor is disposed in the hub. The circuit board is used to control the fan motor, so that the vanes rotate related to an axis of the hub for generating an air flow. The fan housing has a main body portion, a protruding portion and a fixing portion, wherein the protruding portion is located in a side of the main body portion, the vane module and the fan motor are disposed in the main body portion and the circuit board is disposed in the protruding portion.

Abstract: In accordance with at least some embodiments, a computer system include a chassis and a main airflow channel within the chassis. The computer system also includes multiple processors and multiple memory banks positioned in the main airflow channel. The computer system also includes a removable airflow guide assembly installed in the main airflow channel, wherein the removable airflow guide assembly divides the main airflow channel into a processor-side airflow channel and a memory-side airflow channel.

Abstract: An electronic unit includes: a circuit board that has a device mounting surface mounted with circuit devices and that is supported in a condition that the device mounting surface is arranged in a direction of gravity; an opposed member that is disposed in opposition to the circuit board so that a passage space through which a refrigerant for cooling the circuit devices passes is formed between the opposed member and the device mounting surface; an exhaust unit that is disposed in opposition to the circuit devices disposed on the circuit board and that exhausts the refrigerant having passed through the passage space; and a protruding member that is provided in an upper portion of the exhaust unit in the direction of gravity and that protrudes from the opposed member toward the circuit devices.

Abstract: In an air conditioner, air-supply passages cross air-discharge passages, and heat exchangers are disposed at intersections between the air-supply passages and the air-discharge passages. This increases the effective heat-exchanging areas of the heat exchangers. In addition, the air conditioner is configured such that the air conditioner can be easily installed and repaired even when the air conditioner is rotated to be properly connected with air-supply ducts and air-discharge ducts.

Abstract: A computer system includes a chassis with a fan installed therein, a cover plate adapted to be attached to the chassis, and a noise absorber attached to the cover plate. The fan is capable of generating an amount of air flow for cooling at least a component in the chassis. The noise absorber includes a plurality of protrusions facing the fan and capable of damping the air flow that impacts the cover plate and decreasing an acoustic noise level of the computer system.

Abstract: An electronic device includes a first and a second air passages. A first and a second electronic components locate in the first and second air passages, respectively. A first heat sink includes a first heat dissipation portion contacting the first electronic component and located in the first air passage and a second heat dissipation portion located in the second air passage. A second heat sink includes a first heat dissipation portion contacting the second electronic component and located in the second air passage and a second heat dissipation portion located in the first air passage. The first heat dissipation portion of the first heat sink aligns with the second heat dissipation portion of the second heat sink and the second heat dissipation portion of the first heat sink aligns with the first heat dissipation portion of the second heat sink along a flowing direction of the t air passage.

Abstract: An apparatus includes a side plate and a rear plate perpendicular to the side plate. A motherboard is mounted on the side plate. The motherboard has a heat source attached thereon. The rear plate defines a ventilation area. The ventilation and the heat source are located at different heights. A fan is mounted on the ventilation area. The fan inclines towards the plurality of expansion cards.

Abstract: A tandem fan system with an airflow-straightening heat exchanger removes heat from an airflow while providing optimal airflow pressure. The tandem fan system includes a first fan assembly and a second fan assembly, wherein each fan assembly has an inlet face and an outlet face, and includes at least one fan configured to propel a flow of air from the inlet face to the outlet face. The tandem fan system also includes a heat exchanger coupled between the first and second fan assemblies, wherein the heat exchanger includes at least one fin array and one or more heat pipes. The fin array and heat pipe combination is configured to draw heat from a flow of air that flows through the heat exchanger, and to straighten the flow of air so that the flow is perpendicular to the inlet face of the second fan assembly.

Abstract: A fan frame for a heat dissipation apparatus is provided. The fan frame includes an outer frame, an inner frame sleeved in the outer frame and slidable relative to the outer frame, a latching mechanism for mechanically securing the inner frame to the outer frame. The latching mechanism includes one or more resilient latches, one or more receiving portions capable of receiving the resilient latches in a first latched position and a second latched position, and an actuator mechanism connected to the outer frame and capable of resisting the resilient latch to cause elastic deformation of the resilient latch, thereby withdrawing the resilient latch from the receiving portion.

Abstract: A self-propelled, low-emission vehicle includes an internal combustion engine, a vehicle cooling assembly, and an engine exhaust assembly disposed within an engine compartment. The vehicle cooling assembly includes an enclosure and a powered fan to vent the enclosure by drawing a stream of cooling air therethrough. The engine exhaust assembly carries exhaust gas through exhaust lines from the engine, which is disposed outside of the enclosure, through an exhaust treatment device, which is disposed inside of the enclosure, and out to the environment. A fan shroud assembly defines an outlet margin of the enclosure and includes a shroud body defining a pair of passageways through which the exhaust lines pass. The fan shroud assembly includes an insulated connection assembly disposed adjacent each passageway to provide sealing connection between the respective exhaust line and the shroud body while prohibiting direct contact between the respective exhaust line and the shroud body.

Abstract: A fan [36] and storage device [37] mounting assembly [1] for an electronic device comprises a base [2] having opposing front [4] and rear [5] walls. The rear wall [5] has a plurality of ventilation openings [11] provided therein. A support [16] has a fan [36] mount [32] arranged adjacent to the front wall [4] and substantially perpendicular thereto and a storage device [37] receiving opening [20] arranged between the fan mount [32] and the ventilation openings [11].

Abstract: Use of vortex generators to improve efficacy of heat sinks used to cool telecommunications, electrical and electro-optical components.

Abstract: A heat-dissipating mechanism includes a first heat-dissipating device, a first positioning device, a second heat-dissipating device and a second positioning device. The first heat-dissipating device is contacted with a memory module. The first positioning device is disposed on the first heat-dissipating device and includes a protrusion. The second heat-dissipating device is connected with the first heat-dissipating device. The second positioning device has a positioning rail formed in the second heat-dissipating device and corresponding to the protrusion. The second heat-dissipating device is connected with the first heat-dissipating device when the protrusion of the first positioning device is embedded into the positioning rail second positioning device.

Abstract: Systems and methods for controlling the temperature of an electrical device is described. The system includes a heat sink system in conjunction with a thermoelectric assembly. The systems and methods are particularly suitable in NEMA-4 electrical enclosures used in electrical submersible pump applications.

Abstract: Apparatuses, methods, and systems directed to efficient cooling of data centers. Some embodiments of the invention allow encapsulation of cold rows through an enclosure and allow server fans to draw cold air from the cold row encapsulation structure to cool servers installed on the server racks. In other particular embodiments, the systems disclosed can be used to mix outside cool air into the cold row encapsulation structure to cool the servers. In some embodiments, the present invention involves using multiple cold row encapsulation structures to cool the servers installed on the racks.

Abstract: A computer enclosure includes a casing defining a ventilation hole at one side thereof, a power supply and a cooling fan received in the casing. Heat generated by the power supply is taken out by an airflow generated by the cooling fan to an outside of the casing via the ventilation hole. At least one cover sheet covers the ventilation hole of the casing. One side of the cover sheet is pivotally connected to the casing so that the cover sheet is rotatable with respect to the casing. When the cooling fan works, an airflow produced by the cooling fan flows to the ventilation hole and pushes the cover sheet to rotate with respect to the casing, and thus the ventilation hole is exposed; when the cooling fan ceases to work, the cover sheet falls off due to a weight thereof and the cover sheet fully covers the ventilation hole.

Abstract: An external heat dissipation device includes a housing, a circuit board placed in the housing, a fan electrically connected to the circuit board, and a wire electrically connected to the circuit board to power the fan. The housing includes an installation dock defining a receiving space for receiving the fan therein, and an insertion portion extending from the installation dock. A through hole is defined in the installation dock. An air passage is defined in the insertion portion. The fan includes a casing defining a first air hole communicating with the through hole and a second air hole communicating with the air passage.

Abstract: A cooling system includes a plurality of fans and a fan bracket accommodating the fans. Each fan comprises a fan intake and a fan outlet. The fan bracket defines a plurality of air inlets and a plurality of air outlets therein. The fan bracket is provided with a fan guard in each air outlet and a plurality of noise-reducing holes in the fan guard. The air inlets of the fan bracket communicate with the fan intakes and the air outlets of the fan bracket communicate with the fan outlets, respectively. Airflow generated by the fans through the fan outlets comprises a portion exiting through the noise-reducing holes.

Abstract: A housing for holding electronic plug-in assemblies having a component installation space open toward the front side of the housing for the plug-in assemblies and a fan space arranged above the component installation space with a cover plate and a lateral air outlet. The fan space contains at least one axial fan with an air outlet on the top side of the fan. The axial fan is arranged in the fan space such that air is drawn out from the component installation space. An air-guiding plate that runs in the direction of the air outlet of the fan space is positioned between the top side of the fan and the cover plate of the fan space.

Abstract: A heat transfer system is provided. The system includes a heat sink disposed proximate a first circuit. An air mover is adapted to provide airflow, and at least a portion of the airflow can flow through the heat sink along a flow path having a path length. A first portion of the airflow flows along the entire path length through the heat sink. A remaining portion of the airflow exits the heat sink prior to flowing the entire path length.

Abstract: In an air conditioner for a vehicle, a blower of a blower unit includes a double-axial motor having a rotation axis positioned approximately in a vehicle top-bottom direction, a pair of centrifugal fans located at two sides of the double-axial motor in an axial direction, and a pair of scroll casings in which the centrifugal fans are accommodated, respectively. The two air outlet portions are arranged in the vehicle top-bottom direction, and are adjacent to be joined to an air inlet portion of the air conditioning unit, substantially as a single air outlet. Furthermore, the two air outlet portions are located approximately at the same height position as that of the air passing portion of the cooling heat exchanger, and have a height dimension (H2) at its downstream end side that is approximately equal to a height dimension (H1) of the air passing portion of the cooling heat exchanger.

Abstract: A computer system includes a cover and a chassis. The chassis includes a bottom plate parallel to the cover, a first side plate, and a second side plate corresponding to the first side plate. A motherboard and a power supply are fixed on the bottom plate. The power supply is adjacent to the first side plate. The motherboard includes a first heat generating component. The power supply includes a first fan module. A second fan module is secured on the first heat generating component. A first airflow inlet is defined in the first fan module. A second airflow inlet is defined in the second fan module. The first and second airflow inlets are perpendicular to the bottom plate. A third airflow inlet is defined in the cover. The second airflow inlet is located between the first heat generating component and the second side plate.

Abstract: A cooling device for dissipating heat for an electronic device includes a shell to absorb heat generating from a heat generating element in the electronic device, and a number of fins. The shell bounds a heat exchanging space and defines an air intake and an air outlet. The number of fins extends into the heat exchanging space. The shell guides air outside the shell to enter into the shell through the air intake and to exit from the shell through the air outlet after exchanging heat in the heat exchanging space.

Abstract: An interior cooling structure according to the present invention includes a frame in which a plurality of circuit board modules are stacked, with electronic components mounted on the plurality of circuit board modules by being classified by function; an external housing which covers the frame together with the plurality of circuit board modules; a plurality of cooling devices which reduce temperature rises in the external housing caused by heat produced by the plurality of circuit board modules; and a heat generating region a partitioned in such away as to enclose a circuit board module which has the highest total power consumption out of the plurality of circuit board modules, wherein the plurality of cooling devices are arranged in such away as to reduce temperature rises in the heat generating region by displaying capacity higher than capacity of each of the cooling devices.

Abstract: A system, apparatus and method for cool touch housings are described. The apparatus may include a housing arranged to at least partially enclose at least one internal component of a mobile device. A portion of the housing may include an exterior surface spreader, a thin active heat pump with a first side and a second side, wherein the first side of the thin active heat pump is thermally coupled to the exterior surface spreader, and an interior surface spreader thermally coupled to the second side of the thin active heat pump. Other embodiments are described and claimed.

Abstract: A cooling device, such as for cooling a chip and socket may have a centrifugal blower outside of a radial heatsink. In addition, supports for coupling the blower to a center motor may comprise overhead fan blades effectively creating a radial fan in series with the blower to maximize airflow and pressure capability and to minimize the noise. The vertical location of blower may further allow to improve motherboard component as well as system cooling all while reducing the vertical profile of the cooling device.

Abstract: With the storage control device of the present invention, it is possible to mount a larger number of storage devices and to cool them effectively. A plurality of sub-storage units are provided within one storage unit. Each sub-storage unit includes a plurality of hard disk drives, a plurality of enclosures, and a plurality of power supply devices. A cover is divided into a front cover which covers over the front side of a case, and a rear cover which covers over the rear side of the case. Shield portions are provided on the upper sides of the hard disk drives and the enclosures. By these shield portions contacting the adjacent modules (other disk drives and other enclosures), it is possible to reduce the negative influence upon cooling air draft passages within the case, even when a cover has been removed.

Abstract: In the disk array system, in the basic chassis, HDD modules are installed from a front surface in a front part of a backboard, and duplex CTL modules are installed up and down from a rear surface in a rear part, and duplex power source modules containing fans are installed in the left and right sides thereof. By the operation of the fans, in the rear part, the cooling air flows separately into each CTL module and into each power source module, and the cooling air having passed through the area of the duct by a block in the CTL module is drawn by the fans in the power source module through a ventilation hole and is then exhausted outside. The cooling air flow path to the plurality of ICs is divided by the block. The rotation speed of the fans is controlled by using a temperature sensor.

Abstract: A heat dissipating module includes a housing having a bottom wall and a peripheral wall interconnected to a periphery of the bottom wall. The peripheral wall defines a compartment and includes an air inlet in communication with the compartment and an air outlet in communication with the compartment. A stator is received in the compartment of the housing. An impeller is coupled to the stator. A lid can be mounted to the air inlet side of the housing. A plurality of rows of fins is formed on at least one heat conducting section of at least one of the peripheral wall, the bottom wall, and the lid and is located in the compartment.

Abstract: A heat sink includes a frame, a vapor chamber fixed to the frame, and a heat-dissipating plate adhered to one surface of the vapor chamber. The heat-dissipating plate has a first heat-dissipating fins region and a second heat-dissipating fins region. The first heat-dissipating fins region and the second heat-dissipating fins region are composed of a plurality of first heat-dissipating fins and a plurality of second heat-dissipating fins that are arranged at intervals, respectively. The pitch of the first heat-dissipating fins in the first heat-dissipating fins region is smaller than that of the second heat-dissipating fins in the second heat-dissipating fins region. By this arrangement, airflow can flow freely among the respective heat-dissipating fins. The first heat-dissipating fins region is used to dissipate a great amount of heat, while the second heat-dissipating fins region is used to exhaust the air rapidly. Thus, the heat-dissipating efficiency can be increased.

Abstract: According to one embodiment, a heat transfer device includes an array of elongated pins coupled between a base plate and a cover plate. Each pin has a cross-sectional shape with a major width and a minor width that is perpendicular to the major width, in which the length of the minor width is less than the major width. The cover plate and the base plate forming a plenum for the movement of air across the array of pins along a direction parallel to the major width of each pin.

Abstract: A heat-dissipating seat for exclusive use with notebook computers is provided. A cooling fan is provided in a base plate of the heat-dissipating seat. The base plate is bilaterally provided with retractable extension bars for expanding the base plate. Each of the extension bars has an end fixedly provided with a rotatable leg. The heat-dissipating seat has a compact, intricate design that allows easy portability.

Abstract: A system for restricting mixing of air in a data center includes a plurality of racks, each of the racks having a front face and a back face. The system includes an enclosure for collecting air released from the back faces of the plurality of racks, the enclosure configured to substantially contain the air in an area between the first row and the second row and having a roof panel coupled to the first row of racks and the second row of racks configured to span a distance between the first row of racks and the second row of racks. The enclosure is configured to maintain a first air pressure inside of the enclosure that is substantially equal to a second air pressure outside the enclosure.

Abstract: A thermal module includes a mounting plate, a centrifugal fan with a fin assembly arranged at an air outlet thereof, and a heat pipe connected the fin assembly with the heat mounting plate. The centrifugal fan includes a fan housing and an impeller rotatably received in the fan housing. The fan housing is disposed immediately neighboring to the mounting plate and mounted to a lateral side of the mounting plate via a securing structure formed between the fan housing and the mounting plate. The fan housing consists of a base and a cover. The base is made of a plastic material.

Abstract: A computer includes a casing; the computer further comprises a motherboard, a hard disk drive mounting structure and a hard disk drive accommodated in the casing. The motherboard is mounted on a fixing plate of the casing. The hard disk drive mounting structure is located above the motherboard, and includes a heat dissipation apparatus including a heat sink, a mounting frame, and a supporting bracket connected between the mounting frame and a base of the heat sink. A bottom end of the supporting bracket is fixed to the base of the heat sink. A top end of the supporting bracket is fixed to one end of the mounting frame to support the mounting frame, which has another end fixed to a side plate of the casing. The hard disk drive is mounted on the mounting frame.

Abstract: A heat dissipation module comprises a heat pipe forming a condensing section, and a first fin unit and a second fin unit contacting with the condensing section of the heat pipe. The first and second fin units are located neighboring to each other and have different heights. The first and second fin units each comprise a plurality of fins stacked together. A protruding member protrudes from one of the fins of one of the first and second fin units to abut a corresponding neighboring one of the fins of the other one of the first and second fin units, to thereby separate the first fin unit and the second fin unit to limit relative movement of the first fin unit and the second fin unit in a protruding direction of the protruding member.

Abstract: In a vehicular air conditioning apparatus, a first blower unit is connected by a connection duct to a side portion of a casing constituted by respective air passages. On a lower portion of the casing, the first blower unit is connected together with a second blower unit. As a result of a controller controlling driving of an ventilation switching damper, based on a load voltage to a second blower fan of the second blower unit, a first front passage and a first rear passage are placed in communication, whereby a portion of the air from the first blower unit passes through the first front passage, a communication opening, and the first rear passage, and is supplied to a second cooling section of an evaporator, such that when the second blower fan is rotated at a low speed, freezing of water droplets in the second cooling section is avoided.

Abstract: A portable high-voltage test instrument comprises an electronic unit having means for producing a test voltage located in the kV range, a control area cooperating with the electronic unit, at least one terminal for the component or cable to be tested and for an external voltage supply, a housing for permanently accommodating the electronic unit and a cooling system, disposed inside the housing, for cooling the electronic unit, the cooling system comprising an air-cooled assembly having an air inlet and an air outlet. This housing is provided with a lid part that can be moved between an open and a closed position, such that all terminals, the control area and the air inlet and air outlet are covered in closed position thereof, whereas all terminals, the control area and the air inlet and air outlet are unobstructed in open position thereof.

Abstract: An air handling unit has an enclosure, a heat exchanger disposed within the enclosure, and a heating element substantially co-located with the heat exchanger within the enclosure. An air handling unit has a cabinet with a first air opening and a second air opening. A blower is disposed within the cabinet adjacent to the first air opening and a heat exchanger is disposed within the cabinet adjacent to an air outlet of the blower unit and also adjacent to the second air opening. At least one heating element is located adjacent the heat exchanger. A method of constructing an air handling unit includes forming an air handling enclosure, mounting a blower in the air handling enclosure, mounting a heat exchanger in the air handling enclosure downstream of the blower, and mounting at least one heating element in the air handing enclosure downstream of the blower.

Abstract: A heat dissipation structure includes an electronic device, and a cooling device mounted to the electronic device. The electronic device includes a housing, and a heat generating element mounted in the housing. The housing defines an opening. The cooling device comprises a shell abutting against the heat generating element through the opening, a number of fins extending from the shell, a fan mounted to the shell, an air intake, and an air outlet. The air intake and the air outlet are located outside the housing.

Abstract: A thermal management system includes an air duct assembly comprising a supply air duct having an air inlet opening, a return air duct having an air exit opening and a plurality of distribution air ducts configured to be in fluid communication with the air inlet opening of the supply air duct and with the air exit opening of the return air duct. A fan is disposed within the air duct assembly to direct air from the air inlet opening of the supply air duct through the supply air duct and out the air exit opening of the return air duct. The fan and supply duct are disposed to direct air over a first surface of a heat sink. A second opposing surface of the heat sink is disposed over and configured to be in thermal contact with a plurality of active circuits disposed on a first surface of a radio frequency (RF) multi-layer printing wiring board (PWB).

Abstract: A heat dissipating assembly includes a heat exchanger and an air duct. The heat exchanger includes a plurality of fins aligned in a row, and the fins cooperatively define a plurality of heat dissipating channels. A guiding slot is defined in the heat exchanger. The air duct defines a passage. A positioning hook extends from the air duct and engages in the guiding slot to so that the air duct passage and are aligned with the heat dissipating channels so that an air flow is capable of passing through the air duct passage via the heat dissipating channels.

Abstract: A waterproof and heat-dissipating module mounted on an electronic device includes a housing structure, a compartment structure, and a fan. A first ventilation hole, a second ventilation hole, a first drainage holes, and a second drainage holes are formed on the housing structure. The compartment structure is disposed inside the housing structure and for partitioning an inside space of the housing structure off that includes an inhaling chamber, a fan room, an accommodated space, and an exhausting chamber. The fan is disposed inside the fan room so that airflow is guided from the first ventilation hole to the second ventilation hole via the inhaling chamber, the fan room, the accommodated space, and the exhausting chamber so as to dissipate heat from circuit boards disposed inside the accommodated space away.

Abstract: An apparatus for efficiently distributing warm air generated by a steam radiator which comprises a booster fan assembly positioned adjacent to the steam radiator. A mechanism is coupled to the booster fan assembly for circulating the warm air away from the steam radiator and out into a room.

Abstract: In the heat exchanger of a heat exchange device of the present invention, first protrusions (26) are provided on a part of first rectification walls (22) of first plate member (15) so as to protrude into first recessed portions (25) which are formed on second plate member (16) close to first plate member (15) when second rectification walls are formed on second plate member (16). Second protrusions (27) are provided on apart of second rectification walls (23) of second plate member (16) so as to protrude into second recessed portions (25a) which are formed on third plate member (17) close to second plate member (16) when third rectification walls (24) are formed on third plate member (17).