38results about How to "Improved noise attenuation" patented technology

A filter assembly configured for acoustic dampening for use with compressor assemblies such as oxygen concentrators including a compartmented housing member having an inlet opening, an outlet opening, a filter member, and a plurality of noise attenuating members positioned and located therewithin. The configuration of the compartmented housing member in conjunction with the positioning and location of the filter member and the noise attenuating members therewithin all contribute to absorb and dissipate any sound waves generated within the housing member due to air flow movement therethrough. This substantially reduces and minimizes noise associated with the present filter assembly.

A liner assembly for a fan case includes a noise attenuation layer covered by a face sheet. The face sheet includes openings to the underlying noise attenuation layer. The face sheet and noise attenuation layer include acoustically transparent joints. The noise attenuation layer includes a first side joined to a second side at a seam by an adhesive strip. The adhesive strip bonds the first side to the second side without filling any chambers. The face sheet includes a joint filled with an adhesive providing the desired uninterrupted surface within the fan case. Openings are formed through the joint and the adhesive to communicate with the underlying noise attenuation layer. The joint and seam become essentially transparent acoustically to improve noise attenuation performance.

A flexible noise attenuating cutting line for use in rotary vegetation trimmers formed by extruding a pair of molten monofilament strands in proximate disposition through a rotating die so as to form a line comprised of two monofilament polymer strands bonded together in a twisted disposition about a central longitudinal axis so as to define a pair of substantially V-shaped opposed troughs extending helically along and about the line.

An improved de-ghosting method and system that utilizes multi-component marine seismic data recorded in a fluid medium. The method makes use of two types of data: pressure data that represents the pressure in the fluid medium, such as sea water, at a number of locations; and vertical particle motion data that represents the vertical particle motion of the acoustic energy propagating in the fluid medium at a number of locations within the same spatial area as the pressure data. The vertical particle motion data can be in various forms, for example, velocity, pressure gradient, displacement, or acceleration. A spatial filter is designed so as to be effective at separating up and down propagating acoustic energy over substantially the entire range of non-horizontal incidence angles in the fluid medium. The spatial filter is applied to either the vertical particle motion data or to the pressure data, and then combined with the other data to generate pressure data that has its up and down propagating components separated.

A filter assembly for use with compressor assemblies such as oxygen concentrators, ventilators and other breathing apparatus including a compartmented housing member having at least one inlet opening, an outlet opening, a filter member, and an adjustment member associated with the at least one outlet opening for varying the size of the at least one outlet opening for adjusting the amount of ambient air entering the filter assembly.

This method comprises the following steps in the frequency domain:a) estimating a probability that speech is present;b) estimating a spectral covariance matrix of the noise picked up by the sensors, this estimation being modulated by the probability that speech is present;c) estimating the transfer functions of the acoustic channels between the source of speech and at least some of the sensors relative to a reference constituted by the signal picked up by one of the sensors, this estimation being modulated by the probability that speech is present;d) calculating an optimal linear projector giving a single combined signal from the signals picked up by at least some of the sensors, from the spectral covariance matrix, and from the estimated transfer functions; ande) on the basis of the probability that speech is present and of the combined signal output from the projector, selectively reducing the noise by applying variable gain.

The suction arrangement of the present invention is for a hermetic compressor of the type which includes a hermetic shell; a cylinder block defining, in a single piece, a shell portion and a compression cylinder having an end opened to the exterior of the hermetic shell and closed by a valve plate; a head affixed to the cylinder block onto the valve plate so as to define, with the latter, at least one suction chamber receiving refrigerant gas from a gas inlet pipe external to the hermetic shell. The suction arrangement of the present invention comprises a gas inlet duct defined through the shell portion and through the valve plate and having an outer end hermetically coupled to the gas inlet pipe and an inner end opened to the suction chamber.

A recursive filter system and method is provided. A weighted value of luminance and chrominance of a stored picture element is generated by summing weighted values of luminance and chrominance of a picture element and neighboring picture elements. A first proportional parameter for the stored picture element is generated with a sum of differences between the luminance and chrominance of the stored picture element and surrounding picture elements. A weighted picture element is generated from a proportion of the stored picture element and a complimentary proportion of the weighted value. Picture elements of the next image and a second proportional parameter are inputted. A filtered image is generated by combining a proportion of each input picture element of the next image with a complementary proportion of the weighted stored picture element of the first image. The filtered image is stored for corresponding combination with a succeeding image.

A hermetic compressor, comprises: a hermetic shell (1); a cylinder block (2) defining, a shell portion (Ia) and a compression cylinder (3) having an end (3a) opened to the exterior of the hermetic shell (1) and closed by a valve plate (5); a head (6) affixed to the cylinder block (2), over the valve plate (5) so as to define, with the latter, at least one discharge chamber (10). The cylinder block (2) incorporates a tubular projection (20) surrounding the valve plate (5) and at least part of the head (6). An outer cover (30) is hermetically affixed to the tubular projection (20) for defining therewith a discharge plenum (31) in fluid communication with the discharge chamber (10), the tubular projection (20) or the outer cover (30) being provided with a refrigerant gas outlet (40) opened to the exterior of the hermetic shell (1).

A direct current motor for a vehicle, according to the present invention, comprises: a cover assembly (10); a yoke assembly (30) having a lower housing (40) coupled with the cover assembly (10), and aplurality of excitation poles (31) arranged inside the cover assembly (10); an armature assembly (20) comprising an armature core (22) and upper and lower insulators (23, 24), the armature core (22)having a plurality of teeth (22A) around which coils (21) interacting with the excitation poles (31) are wound, and the upper and lower insulators (23, 24) coupling to the upper and lower portions, respectively, of the armature core (22); a commutator (50) installed on the lower side of the armature core (22) and having commutator segments (51) of which the number corresponds to the number of theexcitation poles (31); a brush holder (60) arranged on the inner side of the lower housing (40) and comprising a brush (61) selectively making contact with the commutator (50) according to the rotation of the armature assembly (20); a rotational shaft (70) having the armature core (22) and the commutator (50) coupled thereto so as to rotate therewith; an up / down / left / right vibration and noise dampening buffer means (80) installed on the upper and lower portions, respectively, of the rotational shaft (70); a brush holder left / right vibration and noise dampening buffer means (90) installed on the brush holder (60) so as to be insertedly installed in a yoke cylindrical body (32) constituting the yoke assembly (30); a grounding means (110) comprising a power supply connector (100) coupled to aconnector receiving part (63) formed on a support (62) of the brush holder (60); and an insulating means (120) installed so as to make surface-contact with the upper side of the commutator (50) installed in the center of the support (62) of the brush holder (60).

A liner assembly includes a plurality of aligned passages providing a large open area combined with openings much smaller than a length of the passages. The plurality of passages are disposed parallel with each other and include an opening transverse to incident sound waves. The passages are separated by walls and are blocked at an end distal from the openings. Sound waves incident on a face of the liner enter the passages and are dissipated by viscous losses. Sound energy is further dissipated as thermal energy to the walls of the passages. The long narrow passages provide the desired visco-thermal losses for sound energy in a broad frequency range.

A non-structural multi-part panel including at least two layers, a first layer of foamed material and a second layer applied to at least one side of the first layer, the second layer of cellulosic material.

An improved de-ghosting method and system that utilizes multi-component marine seismic data recorded in a fluid medium. The method makes use of two types of data: pressure data that represents the pressure in the fluid medium, such as sea water, at a number of locations; and vertical particle motion data that represents the vertical particle motion of the acoustic energy propagating in the fluid medium at a number of locations within the same spatial area as the pressure data. The vertical particle motion data can be in various forms, for example, velocity, pressure gradient, displacement, or acceleration. A spatial filter is designed so as to be effective at separating up and down propagating acoustic energy over substantially the entire range of non-horizontal incidence angles in the fluid medium. The spatial filter is applied to either the vertical particle motion data or to the pressure data, and then combined with the other data to generate pressure data that has its up and down propagating components separated.

A process for forming flexible noise attenuating cutting line for use in rotary vegetation trimmers formed of at least two monofilament polymer strands bonded together in a twisted disposition or a single strand twisted about its central axis in which the strand or strands are extruded in a molten disposition through a single die that is rotated during the extruding step either to twist the two strands together about a central longitudinal axis or a single strand about its own longitudinal axis such that upon cooling, stretching and heating, a flexible noise attenuating line is created in a continuous online process.