Electical Type Devices (e.g., Transformers, Motors, Etc.) Patents (Class 181/202)
  • Patent number: 5183975
    Abstract: A muffler for an air-cooling system used for channeling air for cooling an electric motor comprises a housing mounted on the electric motor and formed with an air inlet; and an air outlet and an air passage extending between and connecting the inlet and the outlet. Air from outside the housing employed to cool the motor enters through the inlet, flows through the passage and exits through the outlet. Noise having a spectrum of frequencies including a relatively low main discrete frequency, which corresponds to a relatively long wave-length, and a plurality of higher frequencies is generated in the cooling air during operation of the motor and its cooling system. A baffle is positioned within the housing adjacent to the outlet to interrupt lines of sight from the air passage to the outside of the housing. The housing and the baffle are made of a metal or plastic and have sufficient mass to attenuate the higher frequencies of the noise spectrum to a substantial degree.
    Type: Grant
    Filed: May 15, 1991
    Date of Patent: February 2, 1993
    Assignee: Siemens Energy & Automation, Inc.
    Inventors: Jack L. Craggs, Robert R. Burke
  • Patent number: 5173020
    Abstract: A centrifugal compressor is provided with a collector for receiving refrigerant from the diffuser, and sound absorbent segments are placed within the collector and retained in place against one wall thereof. One method of retention is by way of a ring and a plurality of spring clip members. The silencer segments and the retaining ring and spring clip members are placed into the collector prior to installation of the diffuser. As the diffuser is attached to the collector, one edge engages a side of the ring so as to axially move it into its final fixed position, while at the same time causing the attached spring clip members to be placed in tension against the silencer segments to secure them in place.
    Type: Grant
    Filed: February 19, 1991
    Date of Patent: December 22, 1992
    Assignee: Carrier Corporation
    Inventors: Charles E. Ebbing, Thomas M. Zinsmeyer, Edson H. Byrns
  • Patent number: 5151018
    Abstract: There is disclosed an improved two-piece enclosure for a refrigerant compressor which is very simple in design and which effectively attenuates the sound produced by that compressor and, at the same time, requires a minimum amount of additional space and provides easy access to the compressor for service and the like. Two embodiments are shown, one with sound insulation on the walls of the container and another with sound insulation on the compressor.
    Type: Grant
    Filed: July 31, 1990
    Date of Patent: September 29, 1992
    Assignee: Copeland Corporation
    Inventors: Harry B. Clendenin, James F. Fogt
  • Patent number: 5125378
    Abstract: A cooling system is provided for enclosed first and second heat sources including an enclosure substantially enclosing the heat sources. The first and second heat sources are positioned in the enclosure. A heat exchanger, also positioned within the enclosure, is connected through the enclosure to an external source of cooling fluid and is adapted for cooling air within the enclosure. The heat exchanger has a first surface for receiving the air to be cooled and a second surface for expelling cooled air. First and second air circulation means are provided within the enclosure for circulating air past both the first and second heat sources and the heat exchanger. A first baffle portion separates the first and second heat sources and extends to the first surface of the heat exchanger, and a second baffle portion extends to the second surface of the heat exchanger.
    Type: Grant
    Filed: May 13, 1991
    Date of Patent: June 30, 1992
    Assignee: Westerbeke Corporation
    Inventor: John H. Westerbeke, Jr.
  • Patent number: 5026476
    Abstract: A rotary machine having a machine body and a cover covering an opening of the body. The cover is fixed to the body by an improved vibration-absorbent structure. A peripheral edge of the cover which is adjacent to the body has plate-spring-shaped mounting brackets whose distal ends project from the edge. The end of the machine body which is adjacent to the cover has mounting portions that are grooves or holes. The bracket distal ends are inserted into the mounting portions through rubber vibration insulating members. With the structure, the cover is assembled at improved efficiency and is restrained from vibration.
    Type: Grant
    Filed: June 6, 1990
    Date of Patent: June 25, 1991
    Assignee: Sumitomo Heavy Industries, Ltd.
    Inventors: Noriyuki Ishimoto, Hirofumi Iida
  • Patent number: 5014660
    Abstract: A cooling system is provided for an enclosed heat source including an enclosure substantially enclosing the heat source. The heat source is positioned in the enclosure. A heat exchanger, also positioned within the enclosure, is connected through the enclosure to an external source of cooling fluid and is adapted for cooling air within the enclosure. Air circulation means are provided within the enclosure for circulating air past both the heat source and the heat exchanger. A method of cooling an air cooled heat source within an enclosure is also provided.
    Type: Grant
    Filed: October 29, 1990
    Date of Patent: May 14, 1991
    Assignee: Westerbeke Corporation
    Inventor: John H. Westerbeke, Jr.
  • Patent number: 4982812
    Abstract: A noise-preventive apparatus for compressor used in an air conditioner includes a double-wall vacuum jacket encompassing a compressor in the vacuum jacket so that the noise caused in a runnign compressor will not be transmitted outwardly through a vacuum chamber formed in the double-wall vacuum jacket for preventing noise pollution in an air conditioner.
    Type: Grant
    Filed: October 24, 1989
    Date of Patent: January 8, 1991
    Inventor: Min-su Hwang
  • Patent number: 4914929
    Abstract: A cooling unit suitable for use in an automobile air conditioning system. The cooling unit includes an evaporator disposed in a casing having air inlet and air outlet openings to permit air passage through the evaporator. A vibration absorbing mechanism comprising an elastic material surrounds a peripheral surface of the evaporator and is disposed between the evaporator and the casing to prevent the transfer of vibration from the evaporator to the casing. Accordingly, the vibration absorption mechanism reduces or eliminates noise related to evaporator vibration from reaching the automotive passenger compartment.
    Type: Grant
    Filed: March 17, 1989
    Date of Patent: April 10, 1990
    Assignee: Sanden Corporation
    Inventor: Shimazaki, Seiji
  • Patent number: 4894749
    Abstract: Option-equippable apparatus such as a computer that is not fully equipped with option circuit boards (14) has filler boards (15,16) connected to free board slots (13). In one embodiment, the filler boards (15) simulate the effect of circuit boards on airflow and act to evenly distribute the cooling air flow inside the computer cabinet (10) in order to provide improved cooling of the circuit boards. In another embodiment, the filler boards (16) block airflow between filler boards connected to adjacent board slots to direct more cooling airflow to any slots equipped with option circuit boards. The filler boards are made of electrically-conductive material (30) to absorb electromagnetic radiation emissions, and are covered with acoustically-absorbent material (33) to absorb sound emissions of the apparatus.
    Type: Grant
    Filed: August 31, 1987
    Date of Patent: January 16, 1990
    Assignees: AT&T Information Systems Inc American Telephone and Telegraph Company, AT&T Information Systems, AT&T Bell Laboratories
    Inventors: Gary W. Elko, Paul Howard, Daniel A. Quinlan
  • Patent number: 4883144
    Abstract: A housing for enclosing motorized appliances consists of a structure constructed of noise absorbing materials. A door on the housing, when closed, activates internal circuitry for supplying power to the enclosed appliance. The housing absorbs much of the noise generated during operation of the appliance, allowing conversation and entertainment to continue in a normal manner without noise interruption from the appliance.
    Type: Grant
    Filed: August 26, 1988
    Date of Patent: November 28, 1989
    Inventors: Frederick W. Haushalter, John S. Robinson
  • Patent number: 4879847
    Abstract: A cover for use with a motor and handle extending from the motor comprising, a soft, resilient, fairly rigid, thermoplastic elastomeric material of one-piece construction. The cover has a first body portion having a sidewall and a dome extending from the sidewall defining a cavity to receive the motor, with the dome being spaced from the motor to define a chamber between said dome and motor which serves as a muffler to reduce noise. The cover has a hollow second body portion extending from the first body portion and having a bore to receive the handle.
    Type: Grant
    Filed: March 13, 1989
    Date of Patent: November 14, 1989
    Assignee: Snap-on Tools Corporation
    Inventors: James K. Butzen, Kenneth C. Happ, Robert D. Giese
  • Patent number: 4840251
    Abstract: A noise reducing apparatus in the form of a hollow body comprising two or more passage groups consisting of a plurality of passages. The length of each passage is determined such that the sound waves emitted from the passages of the adjacent passage groups form plane waves which are shifted by a half wavelength so that plane waves interfere each other. The apparatus can be secured to an opening of construction and reduce the level of sound pressure from a sound source without any closed shield construction surrounding the sound source.
    Type: Grant
    Filed: September 30, 1988
    Date of Patent: June 20, 1989
    Assignee: Bridgestone Corporation
    Inventors: Masanori Murase, Naotaka Tomita, Kazuyoshi Iida
  • Patent number: 4834625
    Abstract: An improved fluid pump provided with a ceramic encasement that substantially reduces noise and vibration, resulting in improved acoustic characteristics.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: May 30, 1989
    Assignee: Grant Airmass Corporation
    Inventor: Benton H. Grant
  • Patent number: 4828175
    Abstract: The apparatus for making artificial snow by atomizing water comprises a ductlike housing mounted on a supporting frame, in which a blower is positioned and on whose downstream end a plurality of nozzles or orifices for spraying water or a water-air-mixture are provided. The ductlike housing is constructed double walled. An inner wall of the ductlike housing is provided with a plurality of holes. Sound absorbing material in the interior space located between the inner wall and an outer wall and one electric heater are also provided. Air baffles can also be provided which contain sound absorbing material and are similarly heated.
    Type: Grant
    Filed: February 3, 1988
    Date of Patent: May 9, 1989
    Assignee: SUFAG Sport- Und Freizeitanlagen Gesellschaft m.b.H.
    Inventors: Siegfried Heufler, Hans Sesser
  • Patent number: 4807718
    Abstract: Apparatus for the abatement of noise from cooling fans primarily in computer and business equipment. Noise of mechanical origin is reduced by damping the fan casing, by mass-loading the casing (at low frequencies), by isolating the casing from its surrounds, and by absorbing some of the noise as it is radiated from the fan casing. The foregoing functions are accomplished by a three-part assembly comprising an elastomeric damping-absorption-isolation collar, a massive high inertia collar, and a secondary isolator, which are inserted between the fan and its supportive structure. The assembly also supports the fan without loose fasteners attached to the fan.
    Type: Grant
    Filed: March 2, 1988
    Date of Patent: February 28, 1989
    Assignee: Digital Equipment Corporation
    Inventor: Robert Lotz
  • Patent number: 4733750
    Abstract: An acoustical enclosure for a marine engine generator set includes a squirrel cage fan powered mechanically by the engine and mounted over a large opening in an end of the enclosure. Air inlets are provided to admit external air into the enclosure. A large air flow results, allowing the generator to be operated at full capacity, even at elevated ambient temperatures. Noise is prevented from escaping out of the opening in the end of the enclosure by having the fan placed directly over the opening, where the solid plate of the squirrel cage fan reflects a portion of the noise back into the enclosure where it is absorbed by sound absorbing material lining the inside of the enclosure. A fan duct surrounds the fan and a cover is placed over the duct. The cover is also lined with sound absorbing material to further attenuate any noise not reflected back by the fan.
    Type: Grant
    Filed: February 11, 1987
    Date of Patent: March 29, 1988
    Assignee: Kohler Co.
    Inventors: Randall J. Poirier, Scott J. Haugstad, Martin W. Heinrich
  • Patent number: 4728266
    Abstract: A motor drive vacuum pump comprises a motor provided with a rotor, a stator and a housing holding the rotor and the stator therein, a vacuum pump which is attached on the side surface of the motor housing and is driven by the motor to forcibly feed air from an intake port to a discharge port to thereby generate vacuum, a discharging passage means comprising a discharging hole for introducing the air to be discharged through the discharge port of the vacuum pump into the motor interior and a through hole formed in a part of the housing to discharge the air introduced into the motor interior to the atmosphere, and a discharge valve provided in a part of the discharging passage means.
    Type: Grant
    Filed: March 9, 1987
    Date of Patent: March 1, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akio Matsumoto, Kimiaki Seki
  • Patent number: 4724413
    Abstract: A low-noise transformer, particularly for the use as an output transformer of an inverter, comprising a sound-proof envelope surrounding at least one of the windings for absorbing or screening noise originating from vibration due to electromagnetic force.
    Type: Grant
    Filed: April 11, 1986
    Date of Patent: February 9, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Michio Kataoka
  • Patent number: 4629031
    Abstract: A soundproof engine-operated machine or generator includes a floor having first and second air discharge hole, wall members cooperating with the floor in defining a container, at least one wall member having an air inlet for introducing air into the container, a water-cooled engine disposed in the container, a first cooling fan disposed in front of said engine for delivering air from said air inlet toward said engine to cool the engine, a machine unit such as a generator operable by the water-cooled engine, a radiator attached to the engine, a second cooling fan disposed in front of the radiator for drawing air from behind the radiator therethrough, an exhaust pipe connected to the engine and extending below the floor, a muffler connected to a downstream portion of the exhaust pipe and disposed below the floor, a duct for guiding air from the engine around the exhaust pipe to cool the exhaust pipe and for discharging the air through the first air discharge hole, and a scroll-shaped fan cover for discharging a
    Type: Grant
    Filed: August 23, 1985
    Date of Patent: December 16, 1986
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Shoichi Kato, Teisuke Tsukamoto
  • Patent number: 4558296
    Abstract: A hollow sound damping plate is arranged between a transformer core and an internal limiting surface of a transformer tank filled with insulating fluid. At least one compressive-force transmitting spring member (8) is arranged between the front wall (6) and the rear wall (5).
    Type: Grant
    Filed: February 5, 1985
    Date of Patent: December 10, 1985
    Assignee: ASEA Aktiebolag
    Inventor: Stellan Thoren
  • Patent number: 4514714
    Abstract: A noise-reduction device for a stationary induction apparatus which device comprises a sound insulation panel attached to reinforcing channels provided at the periphery of a tank of the stationary induction apparatus so as to block noises emitted from the outer surface of the tank, a weighty body attached to the sound insulation panel for reducing vibrations of the sound insulation panel and a dynamic damper of which the natural frequency can be adjusted to be made equal to the vibration frequency of the weighty body so as to cancel the vibrations of the weighty body.
    Type: Grant
    Filed: February 15, 1983
    Date of Patent: April 30, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Minoru Kanoi, Yasuro Hori, Yuzuru Kamata
  • Patent number: 4504967
    Abstract: A method of determining the physical location of undesired resonance zones induced by acoustic feedback in a spring reverberation unit and damping the vibration of these resonance zones. The improved spring reverberation unit with damping material located at the resonance points of the unit produces a reverberated audio signal which is substantially free from the screeching and howling caused by acoustic feedback.
    Type: Grant
    Filed: December 16, 1982
    Date of Patent: March 12, 1985
    Assignee: The Marmon Group, Inc.
    Inventors: C. J. Alongi, Jack L. Miller, William W. Radzik
  • Patent number: 4497387
    Abstract: Transformer having an active part thereof disposed in an oil-filled, smooth-walled tank having side walls braced by ribs secured by welding and subdivided into wall-high panels, the panels, respectively, including a sheetmetal wall having a resonance frequency f.sub.o smaller according to the function f.sub.o =(S.multidot.k.sub.f)/B.sup.2 then twice line frequency, wherein S is the thickness of the sheetmetal in cm, B the net panel width in cm, and k.sub.f a constant having an absolute magnitude which depends upon the length-to-width ratio of the panel, upon the modulus of elasticity, upon the transverse contraction and upon the specific gravity of the material used therefor.
    Type: Grant
    Filed: September 1, 1982
    Date of Patent: February 5, 1985
    Assignee: Transformatoren Union Aktiengesellschaft
    Inventor: Erich Reiplinger
  • Patent number: 4449610
    Abstract: A muffler on the intake tube in a hermetically sealed compressor for refrigerating apparatuses in direct communication with the intake chamber located in the compressor cylinder head. The body of the muffler, preferably made of plastic material, consists of two half-shells of identical form and structure assembled in an overlapped way and turned by 180.degree. C. with respect to each other.
    Type: Grant
    Filed: February 17, 1982
    Date of Patent: May 22, 1984
    Assignee: Necchi Societa per Azioni
    Inventor: Alfredo Bar
  • Patent number: 4442419
    Abstract: A static induction apparatus including a vessel for containing a main body of the static induction apparatus, a plurality of reinforcing support members secured to side plates of the vessel and a sound reducing structure. The sound reducing structure includes a plurality of sound reducing members supported between the reinforcing support members and each including a sound insulating panel composed of high damping metal plate, a resilient plate formed of thin metal sheet material interposed between the sound insulating panel and the reinforcing members, and a weight member secured to the vicinity of the boundary between the sound insulating panel and the resilient plate.
    Type: Grant
    Filed: September 29, 1981
    Date of Patent: April 10, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Minoru Kanoi, Yasuro Hori, Masaaki Maejima
  • Patent number: 4402383
    Abstract: A drill motor rigid enclosure is provided for a rock drill motor. The drill motor is encompassed within the enclosure such that viration, torque, and thrust produced by the motor is isolated from the rigid enclosure, therefore noise reduction of the drill motor is achieved.
    Type: Grant
    Filed: September 1, 1981
    Date of Patent: September 6, 1983
    Assignee: Joy Manufacturing Company
    Inventor: Edward A. Bailey
  • Patent number: 4384635
    Abstract: A hermetic compressor housing formed from sheet metal as two housing halves which when joined form a generally ellipsoidal inner surface having a maximum radius of curvature of about one order of magnitude greater than the minimum radius of curvature and deviating from the generally ellipsoidal shape only where necessary for supporting a compressor-motor assembly therein and for joining the housing halves is disclosed and provides a housing of relatively uniform rigidity to reduce the level of sounds radiated thereby. In one specific embodiment all of the audible natural resonant frequencies of the housing are above 3500 Hz.
    Type: Grant
    Filed: June 11, 1980
    Date of Patent: May 24, 1983
    Assignee: Tecumseh Products Company
    Inventor: David C. Lowery
  • Patent number: 4373608
    Abstract: A tuned sound barrier for machines which radiate sound primarily at a few constant, discrete frequencies includes an array of mechanical resonators distributed over the surface of a sound barrier. Each resonator of the array is tuned to present a high mechanical impedance to transmission of mechanical vibration at one of the discrete frequencies emitted by the source machine. The tuned sound barrier may be either a free-standing sound barrier or an attachment to a housing for the machine.
    Type: Grant
    Filed: December 20, 1979
    Date of Patent: February 15, 1983
    Assignee: General Electric Company
    Inventor: David G. Holmes
  • Patent number: 4371858
    Abstract: This invention relates to an isolator for a large-sized static induction apparatus such as transformer and reactor. The static induction apparatus wherein a sound insulation panel is mounted through an elastic body on a reinforcing channel which is disposed on a side plate of an oil tank receiving a main device of the apparatus therein, is characterized by disposing a looped weight beam near that part of the sound insulation panel on which the elastic body is installed.With such construction, noise can be effectively reduced while imparting a satisfactory supporting strength to the mounting part of the sound insulation panel.
    Type: Grant
    Filed: December 18, 1980
    Date of Patent: February 1, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Minoru Kanoi, Yasuro Hori
  • Patent number: 4359085
    Abstract: In the exemplary embodiment, two machines are arranged in a common cabinet-like housing insulated toward the exterior from sound conducted through solids and airborne sound. For the purpose of fresh air supply to the machines, there are provided common fresh air channels connected via an inlet port with the exterior air. In order to discharge the exhaust air, separately arranged exhaust air chambers and/or exhaust air channels are provided which discharge into the open air via a common outlet port, disposed at a location remote from the inlet port. The fresh air channels and the exhaust air channels are so designed and arranged that the air is deflected many times during its flow through the housing. The installation particularly serves the purpose of housing dental vacuum generating and compressed air generating electric machines.
    Type: Grant
    Filed: November 1, 1979
    Date of Patent: November 16, 1982
    Assignee: Siemens Aktiengesellschaft
    Inventor: Lothar Mueller
  • Patent number: 4356884
    Abstract: An acoustical enclosure system, particularly designed for overtable circular saws employed in cutting such materials as metal shapes, is disclosed. The system includes an acoustical enclosure covering the saw and a pair of vibration damping arms covering the workpiece being sawed. This combination of elements results in substantially reduced noise levels within the sawing environment.
    Type: Grant
    Filed: August 31, 1981
    Date of Patent: November 2, 1982
    Assignee: Reynolds Metals Company
    Inventor: David B. Mortimer
  • Patent number: 4347042
    Abstract: A motor compressor unit and a method of reducing noise transmitted therefrom. The motor compressor unit comprises a compressor for compressing a vapor, a motor for driving the compressor, a shell encompassing the compressor and motor, and a supply of lubricant disposed within the shell. The motor compressor unit further comprises a lubricant absorbent, fibrous material positioned against interior surfaces of the shell for dampening sound waves generated within the motor compressor unit, and a cover positioned between the lubricant supply and the fibrous material for separating the fibrous material from the lubricant supply and preventing contamination thereof by the fibrous material.
    Type: Grant
    Filed: June 2, 1980
    Date of Patent: August 31, 1982
    Assignee: Carrier Corporation
    Inventor: Timothy M. Holdsworth
  • Patent number: 4347043
    Abstract: A motor compressor unit and a method of dampening sound waves generated therein. The motor compressor unit comprises a compressor for compressing a vapor, a motor for driving the compressor, a shell encompassing the compressor and motor, and a supply of lubricant disposed within the shell. The motor compressor unit further comprises a perforated lining positioned adjacent to the shell and annularly extending around the compressor for capturing a thin film or lubricant between the shell and the lining.
    Type: Grant
    Filed: June 2, 1980
    Date of Patent: August 31, 1982
    Assignee: Carrier Corporation
    Inventor: Richard D. Morris
  • Patent number: 4345341
    Abstract: A vacuum suction type urinating aid comprises a urine transport tube connected, at one end, with a urine receiver provided with a urine suction opening to be applied to a urinating region, and connected, at the other end, with a urine tank communicating to a vacuum suction device. The vacuum suction device is provided with a partition and support plate around a motor mounted with an impeller, to fit the motor by the support plate to a casing forming an air passage. The suction and the delivery side of the air passage communicate through the impeller. The casing is internally provided with plural silencing partition plates at the suction side and the delivery side of the air passage to divert the air current passing therethrough.
    Type: Grant
    Filed: August 20, 1980
    Date of Patent: August 24, 1982
    Assignee: Kimura Bed Mfg. Company Limited
    Inventor: Shuichi Saito
  • Patent number: 4312421
    Abstract: This disclosure relates to a sound absorbing arrangement for a power lawnmower in which sound absorbing material is provided within the body of the lawnmower to reduce noise by attenuating resonance caused by the lawnmower motor. In addition to reducing noise, the sound absorbing material imparts structural rigidity to the lawnmower body or housing, and also may be used to define air passages within the lawnmower body for use in cooling the motor.
    Type: Grant
    Filed: February 7, 1980
    Date of Patent: January 26, 1982
    Assignee: Black & Decker Inc.
    Inventor: Peter P. Pioch
  • Patent number: 4264282
    Abstract: An air compressor apparatus including noise-reducing means for converting ambient air into compressed air includes an air compressor surrounded by a noise-reducing enclosure and a plurality of shock-absorbing means disposed between the air compressor and the enclosure. The enclosure includes a pair of interior baffle plates which divide the interior of the enclosure into an air inlet chamber, an air outlet chamber and an air compressor chamber therebetween. The air inlet chamber and the air outlet chamber are each open to the atmosphere at a first lower end and are each in communication with the air compressor chamber at a second opposite upper end. The enclosure further includes a fan positioned within the baffle plate between the air compressor chamber and the air outlet chamber which is operable to draw air in through the open end of the air inlet chamber across the air compressor chamber and out the air outlet chamber.
    Type: Grant
    Filed: January 3, 1979
    Date of Patent: April 28, 1981
    Assignee: K. C. Mosier Company
    Inventor: William T. Crago
  • Patent number: 4258821
    Abstract: A flexible sound-absorbent blower cover includes an outer skin of a pliable material shaped to surround the blower and conforming generally to the shape of the blower but oversize to provide a space between the outer skin and the blower. A flexible porous sound-absorbent liner is disposed in the space and is bonded to the outer skin. The blower draws air in through the liner which filters the air. The structure of the flexible one piece cover prevents it from resonating. The cover is provided with a slit which can be opened to facilitate installation and then closed to keep the cover in place on the blower.
    Type: Grant
    Filed: February 7, 1979
    Date of Patent: March 31, 1981
    Inventors: Gary R. Wendt, Maurice P. Walsh
  • Patent number: 4215763
    Abstract: A sound attenuator for transformers comprises a rigid plate fixedly attached to a resilient mass. The sound attenuator is attached to the transformer outer wall in the vicinity of highest sound production. The characteristics of the metal plate and the resilient mass are chosen to produce acoustical radiation out of phase with the noise emitted at the transformer wall surface.
    Type: Grant
    Filed: August 21, 1978
    Date of Patent: August 5, 1980
    Assignee: General Electric Company
    Inventor: Walter J. Pasko
  • Patent number: 4146112
    Abstract: A sound reducing baffle for air cooled electrical apparatus with a ventilated enclosure comprised of a box-like closure member positioned in front of the ventilating openings and open at the back and top thereof to permit the transfer of air.The sound is attenuated by reflections and absorption within the baffle with little or no interference with the transfer of cooling air to and from the enclosure.
    Type: Grant
    Filed: October 31, 1977
    Date of Patent: March 27, 1979
    Assignee: General Electric Company
    Inventor: Gerald O. Usry
  • Patent number: 4095668
    Abstract: A cover for suppressing sound from a machine includes a pair of cover members having sound suppressing material thereon and connected to and supported by a pair of oppositely-disposed brackets mounted on the base of the machine. The cover members may be positioned in a horizontal plane in a closed position at least partially over the machine, and at least one of the cover members is pivotally connected to the brackets to move to an upstanding disposition in an open position. Stop members limit the movement of the pivotally mounted cover member between its open position and its closed position.
    Type: Grant
    Filed: July 6, 1976
    Date of Patent: June 20, 1978
    Assignee: A.B.C.C.O. Industries, Incorporated
    Inventor: Edward A. Derka