Abstract: A ventilation system which provides a ventilating unit which can be installed without structural constraints, and air flow can be controlled effectively by setting the direction of nozzles in various directions and also can reduce the noise from air resistance. The system includes: a damper which is formed in the rear side of the ventilating unit and having barriers which are formed in up and down sides of the inner plane of the ventilating unit alternatively; a blower unit which is connected to the damper and a fan is installed centered by a hinge therein; an ejector which is connected to the blower unit so that the air from the fan of the blower unit is ejected through a nozzle body which is installed therein.

Abstract: A molded plastic air diffusing screen in an air supply system provided for effectively diffusing or deflecting air supplied through a coreless or vane-free duct such that undesirable air turbulence and draft/currents are substantially diminished; more particularly, the novel plastic screen diffuser minimizes noise emanating from the penetrating air supply.

Abstract: An acoustic silencer nozzle for ventilation and exhaust fans. The nozzle provides at least two converging exhaust paths, each of which extend through an area that is adjacent acoustically absorbing media or resonating chambers. In this manner, the noise is reduced at the nozzle or outlet portion and provides a tight plume of high velocity discharge flow. Preferably, the nozzle has at least one opening that allows for ambient atmospheric air to mix with the exhaust gases at the outlet of the nozzle.

Abstract: Soundproofed conduit to discharge fumes, advantageously associated with assemblies to discharge fumes for melting systems in steel production plants, the conduit being located between the ventilation system (14) and an outlet chimney (13), at least the first segment (19a) of the discharge conduit defining a section with a value (A) through which the fumes transit, the conduit (12) defining a path, from the relative ventilation system (14) to the discharge chimney (13), comprising at least two counter-opposed and controlled changes in direction (15a, 15b) defining at least respective consecutive segments (19a, 19b, 19c) arranged one at an angle to another, the changes in direction being functionally configured so as to cause phase and counter-phase effects of the sound waves generated by the fluid in transit, the phase and counter-phase effects having the purpose of at least deadening partly the sound waves caused by the passage of the fluid.

Abstract: A centrifugal fan system for a building, including a centrifugal fan mounted for rotation about a vertical axis and having a bottom inlet. The fan is mounted in a movable housing having a fan chamber and an air outlet arranged in a side thereof. Wheels are mounted on both sides of the fan housing and engage two elongate track members, that extend horizontally and are mounted on a suitable supporting structure. Thus, the fan and its housing can be moved horizontally away from the top of an input flow concentrator. The housing has an internal, perforated scroll-shaped wall and vertical external walls. Sound insulation is located between the scroll-wall and the external walls. An electrical motor is mounted on the side of the housing and is connected to drive the fan.

Abstract: A low noise hood is provided having a housing with an air inlet and an air outlet. A first modular device in the form of an intake muffler with a first air duct passage extending therethrough is mounted within the housing near the air inlet. A second modular device in the form of a discharge muffler with a second air duct passage extending therethrough is mounted within the housing near the air outlet. The second air duct passage is shaped to prevent a straight unobstructed passage for air flow through the second passage. A third device comprising an air moving device is secured by a mounting arrangement within the housing. A first vibration isolator such as a plastic saddle is provided in the mounting arrangement for the air moving device for absorbing vibrations and a second vibration isolator in the form of a flexible connector is positioned between the air moving device and the second air duct passage. A third vibration isolator in a mounting arrangement for the discharge muffler may also be used.

Abstract: An air conditioning system. The system comprises an indoor section and an outdoor section arranged in side-by-side arrangement. The indoor section includes an indoor tangential fan having an axis aligned in a first direction, an indoor heat exchange coil, and a supply air aperture which longitudinally extends in the first direction and avoids line of sight noise transmission from the indoor fan. The system includes an axis commonly supporting and operably coupling the indoor fan and the motor, and a scroll housing within the indoor section and arranged about the indoor tangential fan. The indoor tangential fan, motor and axis are assembled to form a first module, the scroll housing forms a second module and the first module is independently removable from the second module without the necessity of disengaging any connection between the first and second modules. The system includes a fan support bracket supporting a first end of the axis, and the motor supporting a second end of the axis.

Abstract: An outlet structure for an air-conditioner has a fan guard disposed on the outlet side of the air-conditioner for preventing foreign matter from entering to an air blower, and at least one air-direction control vane disposed upstream and/or downstream of the fan guard. The fan guard has elements, except for an outer frame, not in parallel to the rear edge of the upstream air-direction control vane or the front edge of the downstream air-direction control vane. Even in the case where the distance between a fan guard and air-direction control vanes is reduced, and airflows interfere with the fan guard and the air-direction control vanes as the size of air-conditioners is progressively reduced, air-turbulence noise may be reduced.

Abstract: When introducing supply air into a treated space (A), the supply air is conveyed from a source (B) of supply air by way of a terminal device (10) opening into the treated space, the supply air being discharged from the terminal device (10) with a certain momentum substantially vertically and downwardly along an upstanding surface (E) defining the treated space. In a supply air terminal device for introducing the supply air the air passageway (13) between the supply air intake and the supply air outlet is elongate, and the terminal device (10) is adapted to be mounted in a vertical position on an upstanding surface (E) defining the ventilated space (A) with the supply air outlet directed downwardly and positioned adjacent said defining surface.

Abstract: An inside air/outside air switching case employing a rotary door, since an introduced air flows along an inner surface of a circumferential wall of the rotary door, an air flow guiding portion constructed of a plurality of protruding portions formed in a corrugated shape of concavities and convexities is formed on an inner surface of the circumferential wall of the rotary door. In this way, the air flow directed toward a suction inlet is made uniform by means of the guiding portion, and the air flow noise can be suppressed.

Abstract: A kitchen ventilator, including a collecting box (11) supporting on its upper side a fan casing (10) enclosing a chamber which, by means of an essentially vertical partition (21), delimits an inlet channel (23) and a fan housing with an outlet channel (18), respectively. The collecting box (11), via an outlet opening (19) provided in its upper wall, is connected to the inlet channel (23) and the fan housing contains an impeller (16) rotatable in a vertical plane. The inlet side of the impeller (16) is connected to the inlet channel (23) via an essentially circular opening (20) provided in the partition (21) and the outlet side of the impeller (16) is connected to the outlet channel (18). Each of the inlet and outlet channels (23,18) is formed in inserts (22,17) made of sound-absorbing material.

Abstract: An electrically operated source provides a stream of thermally-controlled inflating medium to inflate an inflatable thermal care apparatus for treating a hospital patient while employing active noise cancellation to reduce noise created by the source, thereby provides a reduced noise treatment device for treating hypothermic patients.

Abstract: The invention relates to a vapor exhaust hood with a housing which features at least one intake opening equipped at a minimum with one filter, and features at least one outlet opening, and the inside surfaces of which are in part lined with a sound-deadening material, with a fan arranged in the housing. Arranged in the housing, at least opposite each inlet opening of the fan, is sound-absorbing material which from the opposite inlet opening is spaced at least the radius of the fan wheel. The sound-absorbing material has a surface which in size corresponds at least to a circular surface whose radius matches that of the fan wheel. Further measures for noise reduction consist in the arrangement of a vane in the area of the outlet opening, in the application of sound-deadening and/or sound-damping material as well as in the elastic mounting of fan and/or fan motor.

Abstract: A smoke exhauster includes a CPU, two motors and a switching circuit connected to the CPU. The switching circuit includes a common contact, a parallel contact for connecting the motors in parallel, and a series contact for connecting the motors in series. The common contact is connected to the parallel contact for allow higher power supply to start the motors, and the common contact is connected to the series contact for reducing power supply to the motors in order to reduce the rotational speed of the motors. The motors are connected in series after the motors are started.

Abstract: A ventilation system for a multi-storey building, which system comprises a ventilation apparatus mounted on a roof and provided with fans for generating an inlet air flow and a distributing channel for supplying the inlet air flow to various intermediate levels of the building. A service shaft of the building serves as an inlet air flow channel, which shaft forms a flow path for the inlet-air flow directed from the fans downwards, whereby the service shaft has deflecting means for passing a part of the air flow to each intermediate level of the building.

Abstract: A noise reduction curb for use as an interface with a rooftop air conditioning unit by forming a base upon which the air conditioning unit rests and is mounted on a roof of a building. A noise reduction supply air duct is oriented in the longitudinal dimension of the air conditioning unit and has a supply air inlet fluidly coupled to the supply air source and a supply air outlet fluidly coupled directly to the supply ducts in the building. The supply air inlet is longitudinally displaced from the supply air outlet and is separated therefrom by a flow turbulence reducing substantially straight duct section. A noise reduction return air duct is oriented in the lateral dimension of the air conditioning unit and has a return air inlet fluidly coupled directly to the return air ducts in the building and a return air outlet fluidly coupled to the air conditioning unit. The return air inlet is laterally displaced from the return air outlet.

Abstract: A duct (1) for the distribution of air conditioning from an air treating apparatus (4) into the inner environment (A) of a railway vehicle (C), comprising an inner tube (2) having radial air outlet holes (5) and an outer tube (3) containing the inner tube (2) and formed with air outlet apertures (6), facing towards the inner environment (A) of the vehicle (C) and arranged in opposite positions with respect to the radial holes (5) of the inner tube (2).

Abstract: A clean room system has at least one clean room through which clean air is guided. The clean room has a bottom through which the clean air exits. At least one blower for sucking the clean air from the clean room through the bottom is provided. The blower is in the form of an axial blower operating at low pressure. At least one inlet channel for introducing the clean air leaving the blower into the clean room is provided. Filter units are positioned at the ceiling of the clean room for filtering the clean air before entering the clean room.

Abstract: A system for the ventilation of the crew cabin of a combat vehicle having an engine room (5) separated from the crew cabin (2) in which a radiator (9) having a suction, cooling blower (10) is located. The ventilation system comprises an air suction and cleaning apparatus (12,13,15) having a ventilator (14) and an air distribution channel (16) having blower openings (17) into the crew cabin. Advantageously, a sealable passage opening (20) is provided between the crew cabin (2) and the engine room (5).

Abstract: A non-fibrous acoustic silencing duct member capable of attenuating noise associated with a gaseous medium passing through it. Perforated sidewalls define a gas flow passageway and include at least two opposing walls, each perforated with a number of small holes distributed over its surface. Exterior sidewalls are positioned on the outside of the perforated sidewalls and are spaced therefrom. Enclosed chambers are formed between the perforated and exterior sidewalls, which chambers are of selected depths. One or more screen layers extend along and adjacent to outer surfaces of the perforated sidewalls, these screen layers being located in the chambers. Each screen layer is covered with an array of very small holes that are substantially smaller than the holes in the adjacent perforated sidewall. Internal dividers extend between each perforated sidewall and its respective exterior sidewall in order to divide the space between the sidewalls.

Abstract: A module for the construction of a cleaning room ceiling has a housing wh can be fitted like a tile in the ceiling and which is divided internally into three chambers. A fan in an upper false floor draws air into the housing along an upper chamber which is aligned with a sound-damping lining. Sound-damping baffles are provided on the underside of the upper floor and the upper side and lower floor in the intermediate chamber and the bottom of the lower chamber is closed by high efficiency particle filters.

Abstract: An elevator cage with an ventilator which has supply system for supplying fresh air into the cage and exhaust system for exhausting air from the cage. An active noise controller is provided to at least the supply system to cancel noise which is caused by a supply fan provided in the supply system and changing air force between the cage and a path to guide the cage while the cage moves at high speed.

Abstract: A wind deflector for the sunroof of a vehicle has an elongate body located transversely of the vehicle along the leading edge of the sunroof aperture and extending above the level of the vehicle roof, the elongate body having alternating sections of different height, vane formations being provided between the upper edges of the taller sections to bridge the lower sections and to deflect air passing between the taller sections down through the sunroof aperture.

Abstract: A refrigerator having an air passage duct which contains therein a wire and tube condenser where a cooling air caused by a fan flows. A refrigerator includes: a machine compartment having a fan therein for causing a flow of cooling air, located at a bottom of the refrigerator; an air passasge duct, connected to the machine compartment, containing a wire and tube condenser (referred to as a wire condenser hereinafter), the air duct and the wire condenser being placed at the bottom of the refrigerator; and an exhaust port for discharging an air used for radiating a heat of the wire condenser, wherein the air passage duct is formed in a zigzag shape so that the cooling air flowing through the air passage duct crosses through the wire condenser.

Abstract: Synthetic sponge or other resilient material is joined to the top of a room air-conditioner to absorb the physical impact of rain and dripping water to inhibit the creation of the noise that would otherwise occur. Additionally, a buffer formed with angular surfaces, to absorb and deflect the full impact of rain and dripping water to inhibit the creation of noise that would otherwise occur.

Abstract: An air conduit arrangement for ventilating or air conditioning of a vehicle interior, which is supplied with multi-layered, preformed panel elements.In this arrangement, the air conduits are bordered in the area of the panel elements by two wall sections which are glued together in a permanently resilient manner by means of a connecting flange. Of these, respectively one wall section is formed by the panel element itself and the other wall section by a separate thermoplastic preformed part disposed on the back of the panel element.

Abstract: A ventilator has incorporated in a main body thereof an air blower having a ventilation casing provided with a fan intake opening facing an intake opening of the main body of the ventilator, the inner side of the main body being opened to form the intake opening thereof. A cylindrical soundproof unit including an inner ventilation passage having a larger ventilation area than a fan intake space and formed of a laminated plate which is formed of a plurality of air layers arranged in a direction intersecting the rotation axis of the air blower from the inner ventilation passage, is disposed in a space between the fan intake opening and the intake opening of the main body. The soundproof unit makes it possible to decrease noise generated by the air blower while the ventilation resistance is hardly increased.

Abstract: A method of mixing introduced relatively cold air with warmer air in a room which comprises directing a stream of high-velocity very cool air from jet orifices in the room wall at adult eye level upwardly along the wall to the ceiling, thus thoroughly mixing the introduced and room air and reducing their differential in temperature and velocity virtually to zero by the time the air stream reaches the ceiling.

Abstract: In an air conditioner indoor unit having a ventilator and a heat exchanger, there are provided an upper casing of the ventilator made from a porous structure having air permeability, a lower casing of the ventilator having airtightness, and an air chamber formed at the back of the upper casing.

Abstract: A filter-ventilator-arrangement for employment with clean chambers with at least one ventilator of which the pressure side is located toward an air flow chamber which is limited by boundary walls including a flow chamber formed by at least one annular channel of which one of two boundary walls at least consists of a noise-damping material. Furthermore at least an outer boundary wall consists of noise-damping material. The arrangement includes modular units having several annular channels of which the boundary walls decrease in height from the outside to the inside. Each unit has at least one filter which is arranged in a region below the flow chamber. Innermost boundary walls with inner sides thereof adjoin a plate consisting of noise-damping material. The boundary walls are secured, hanging or suspended on the cover sealing part. At least one heat exchanger lies in a suction region of the ventilator via which the return air flows.

Abstract: A slot ventilator having a canopy with a downwardly facing air inlet and a rear wall having an air outlet which, in use, leads to the slot with which the ventilator is associated includes at least one longitudinally extending baffle which increases the flow path between the inlet face and the outlet, at least one surface of the baffle being formed with corrugations which reduce noise generated by air flowing through the ventilator. The ventilator comprises a profile member affording upper and front walls of the canopy and at least one insert slidable longitudinally into the profile member and affording the baffle or baffles. Preferably, the ventilator includes at least two of the said inserts, one being longer than the other.

Abstract: A construction element for a noise-suppression shed of the type used for ground-testing jet engine aircraft. These sheds usually have transversely extending continuous apertures for the admission of fresh air, the inner face of the shed's roof being provided with spaced liners of a sound-absorbing material defining flowpaths for fresh air entering the interior of the shed. The element comprises a cover panel element carried by a mounting structure and having a stepped profile configuration in the longitudinal direction of the shed, and mutually spaced first and second elements of a sound-absorbing material. The arrangement of a plurality of construction elements in rows extending in the longitudinal and transverse directions and interconnection of the respective mounting structures results in the formation of continuous air inlet gaps extending over the full width of the roof and passing between the sound-absorbing liners.

Abstract: In an air terminal having an inflatable bellows expanding toward a pair of spaced cut-off plates, a sealing element is attached to the central portion of that side of the bellows adjacent to the cut-off plates. The transversely extending ends of the sealing element are not secured to the bellows but are free to separate therefrom as the bellows is expanded to thereby more easily engage the cut-off plates. A pair of foam strips are provided near the transverse ends of the sealing element so as to thereby provide a substantially normally extending surface against which the flowing air will impinge so as to thereby reduce the sound emanating therefrom. A pair of vibration damper clips extend from the cut-off plates and engage the foam strips to prevent any vibration thereof. Pads are secured to the edges of the cut-off plates so as to engage the seal element then thereby enhancing the sealing relationship between the cut-off plates and the seal element.

Abstract: A knock-down sound attenuating system (10) is provided as a portable enclosure having significant sound attenuating properties, while still being easily assembled and disassembled. The knock-down sound attenuating system (10) includes a plurality of sound attenuating wall partitions (14,16) whose longitudinally extended end portions have at least one longitudinally extended recess (78) formed therein. System (10) further includes a coupling gasket (50,70) having at least a pair of opposing projecting members (52 and 54), (74 and 76) for receipt within a recess (78) formed in a respective one of the wall partition end portions. Coupling gaskets (50,70) simultaneously provides both an interlocking between adjacent wall partitions (14,16) and an acoustic seal for the interface therebetween. To secure one wall partition (14,16) to another, system (10) further includes a flexible coupling system (18) comprising a strap-like member (28) coupled adjacent a longitudinal side of a partition (14).

Abstract: A ventilation device comprises a hollow body having an air inlet end and an ir outlet end, swirl disk associated with the air outlet end and a perforated disk associated with the air inlet end.