Abstract: Honeycomb structures, glass fiber mats, and polyurethane on both sides with respect to a perforated plate. A sound absorption hole is formed in at least one of the glass fiber mat and the polyurethane arranged on both sides of the honeycomb structure and passes through each cell, so that sound absorption performance in a high frequency band as well as a low frequency band can be improved using multilayer sound absorption characteristics. Noise passing through the honeycomb structure is changed to noise to be absorbed. Since the diameters of the sound absorption holes formed to pass through the honeycomb structures arranged on both sides of the perforated plate are different, a sound absorption band of a desired frequency may be easily adjusted. The sound absorption performance in a low frequency band of 1,000 Hz and a high frequency band of 5,000 Hz or higher can be improved.

Abstract: The present disclosure relates generally to acoustic panels, for example, suitable for use in a ceiling to control sound. The present disclosure relates more particularly to an acoustic ceiling panel including an acoustic substrate formed of a porous material having an air flow resistivity of at least 300 kPa*s/m2. The acoustic substrate includes an upper face and a lower face with a pattern of perforations formed therein, where the pattern of perforations covers at least 6% of the area of the lower face. The acoustic ceiling panel also includes a backing layer disposed over the upper face of the acoustic substrate and a veil disposed over the lower face.

Abstract: The present invention addresses the problem of providing a sound insulating structure which provides a sufficient sound insulating effect even when an adhesive layer is arranged therein, and in which a shift in the frequency band where the sound insulating effect is generated is unlikely to occur. This sound insulating structure includes, at least: a sound insulating member that includes a sheet-like sheet section and plural projections arranged on the sheet section; and an adhesive layer arranged on a surface of the sheet section on the opposite side of the side provided with the projections, and the sound insulating structure satisfies the following Formula (1): E_glue/I_glue>0.5×(E_membrane/H) (1) (wherein, E_glue (MPa): storage modulus of adhesive layer, I_glue (mm): average thickness of adhesive layer, E_membrane (MPa): storage modulus of sheet section and projections, and H (mm): average height of sheet section and projections).

Abstract: An apparatus for reducing sound levels in an HVAC system, the apparatus including a housing configured to be positioned within an air inlet vent for an HVAC system. The housing includes a first opening configured to intake air and a second opening configured to out put air and a plurality of baffles positioned within said housing, each baffle including a body defining a volume and has a plurality of perforations, wherein each baffle is affixed to the housing and wherein the plurality of perforations are configured to allow airflow through the volume of the body and redirecting sound waves.

Abstract: An acoustic panel including first and second cellular structures, the first cellular structure including a set-back portion to form a recess dimensioned to accommodate the second cellular structure such that first faces of the first and second cellular structures, in contact with a first, acoustically resistive layer, are coplanar and that first edge faces of the first and second cellular structures are coplanar when the second edge face of the second cellular structure is in contact with the set-back portion. By virtue of the set-back portion, the first and second cellular structures are positioned correctly with respect to one another, thus contributing to an optimization of the acoustic treatment.

Abstract: A rotating electric machine includes a shaft angle sensor communicating with an external controller via differential signaling. This construction permits the controller to be located away from the axial end of the motor while reliably transmitting rotor angle or speed information to the controller over a relatively long electrical harness. The shaft angle sensor is mounted on a sensor board carried by the machine casing at the non-drive end of the rotor shaft. The sensor board can optionally act as a hub at which signals from multiple machine sensors are gathered to be placed in communication with the controller via the same electrical harness used to transmit the sensor information.

Abstract: A parallel-walled ventilation duct assembly with integrated low-profile subducts, and/or methods of manufacturing the assembly are provided. The assembly of embodiments includes a main shaft body defined by at least one wall surrounding an interior cavity and at least one low-profile subduct disposed within the interior cavity. The cross-sectional area of the main shaft body has a rectangular or an obround shape. The low-profile subduct includes an interior channel defined by a plurality of walls. The low-profile subduct is integrated into at least one wall of the main shaft body such that at least one wall of the plurality of walls of the low-profile subduct includes at least a portion of an interior surface of the at least one wall of the main shaft body, and the portion of the interior surface of the at least one wall includes a flat portion of the interior surface.

Abstract: An electric machine including a stator (2) with a winding (3) having a plurality of conductors (4) associated with one or more phases and interconnected with each other, the ends (6) of at least two conductors (4) are associated with a phase projecting axially or radially from the winding (3) at the inner circumference and/or the outer circumference of the winding (3) and a connected to a power connection (9) that is mounted radially outside the winding (3) by a common connecting conductor (12a).

Abstract: An axial flux motor assembly is disclosed and includes: an axial flux motor comprising a rotor, and a first stator; and a power inverter assembly. The power module assembly includes: a printed circuit board; a control module mounted on the printed circuit board; power module assemblies connected to the printed circuit board and controlled by the control module; and a cold plate. The cold plate is disposed between the first stator and the power module assemblies and includes a first side and a second side, which is opposite the first side. The cold plate cools the power module assemblies via the first side and the first stator via the second side.

Abstract: The present application discloses a sound absorbing device to be placed in an airflow that is in a first direction. The sound absorbing device includes a housing; a plurality of sound absorbing units disposed in the housing to be passed by the airflow, the plurality of sound absorbing units being arranged in a direction perpendicular to the first direction, any two adjacent sound absorbing units being separated by a gap; and a plurality of supports fixed in the housing. The plurality of sound absorbing units are fixed to the housing through the plurality of supports.

Abstract: A compact muffler (40) for an engine exhaust system, which is particularly applicable for use with small, reciprocating piston two-stroke engines of the type used on unmanned aerial vehicles (UAVs). The compact muffler (40) comprises an exhaust gas flow path (67) between an inlet (61) and an outlet (63). The exhaust gas flow path (67) comprises a plurality of adjacent flow passages (65), wherein at least two of the adjacent flow passages (65) are fluidly connected in series to enable the flow of exhaust gas from one to the other along the flow path (67). The adjacent flow passages (65) are configured for fluid flow therealong in opposed directions. A bypass passage (70) is provided between the two adjacent flow passages (65) for further communication between the two flow passages and to promote an equalisation of fluid pressure within the two adjacent passages (65). A UAV having an internal combustion engine (31) fitted with an exhaust system comprising the compact muffler (40) is also disclosed.

Abstract: An acoustic attenuation panel includes a cellular structure including a plurality of acoustic cells separated from one another by peripheral partitions, a perforated acoustic structure, the perforated acoustic structure and the cellular structure being formed in one piece in a first material, and a porous acoustic layer formed of a second material and fastened to a surface of the perforated acoustic structure by entangling the first material and the second material.

Abstract: The present invention may provide a motor including a shaft, a rotor coupled to the shaft, a stator disposed to correspond to the rotor, a busbar disposed above the stator, a cover disposed above the busbar, and a power terminal unit coupled to the cover and electrically connected to the busbar, wherein the busbar includes a first terminal, the power terminal unit includes a second body and a second terminal disposed on the second body, the cover includes a first hole, and a first end portion of the first terminal, which passes through the first hole and is disposed in the second body, and a second end portion of the second terminal are in contact with each other in the second body.

Abstract: The present disclosure provides a device for full-wave field seismic source based on a gas explosion technology and a method for acquiring seismic data. The device includes a cylindrical explosion-proof metal outer barrel, and four sides of the explosion-proof metal outer barrel are fixedly connected to four high-strength steel plates. The device also includes a cylindrical explosion-proof metal gas explosion inner barrel and pipelines for injecting high-pressure air and high-pressure gas into the gas explosion inner barrel. A center of the gas explosion inner barrel is installed with an electronic ignition gun, which is connected to a GPS timing module connected to the electronic ignition gun. The device further includes a controller configured to control a seismic source of a gas explosion full-wave field.

Abstract: The invention provides a speaker module for a mobile terminal provided with a sound output port. The speaker module includes a speaker box, and the speaker box includes a sound output opening. The speaker module also includes a horn barrel connected with the sound output opening. The sound output opening includes a first sound output opening and a second sound output opening. Compared with the related art, the present invention can realize multi-level resonance, small size, convenient to widen the frequency band range and easy to adapt to the mobile terminal.

Abstract: The present invention provides a substrate that is highly resistant to ESD, on which a reverse sound hole type MEMS microphone can be mounted. The substrate has one surface connected to a MEMS microphone, and comprises a substrate sound hole that penetrates through the substrate and communicates with a sound hole of the MEMS microphone, and a GND pad disposed around the substrate sound hole on another surface of the substrate.

Abstract: An improved sound reducing panel is disclosed comprising a front porous sheet for enabling sound to enter into the sound reducing panel and a rear non-porous sheet. A sound absorbing member dissipates sound entering into the front porous sheet. A sound blocking member blocks sound from exiting from the sound absorbing member. A decoupling member reduces sonic vibration from being transferred from the sound blocking member to the rear non-porous sheet. One embodiment includes a drenching shield for inhibiting water from entering the sound absorbing member. Another embodiment includes a decorative or artistic image located on the sound reducing panel.

Abstract: An example speaker module includes a speaker housing including a conduit extending to an internal space; a speaker component positioned in a first area of the internal space adjacent to the conduit; a vent hole spaced apart from the speaker component and passing through at least part of the speaker housing; a sound absorbing material disposed in a second area of the internal space to be positioned adjacent to the speaker component to absorb a sound generated from the speaker component; and a guide structure disposed to surround the vent hole and including at least one protrusion protruding towards the internal space.

Abstract: A damping panel includes a first metal and a second metal. The first metal has a first surface and a second surface opposite the first surface. The second metal portion has a third surface and a fourth surface opposite the third surface. A fixed region is where the second surface of the first metal is fixed to the third surface of the second metal. A non-fixed region is where the second surface is not fixed to the third surface. A cavity is disposed between the second surface and the third surface at the non-fixed region. A damping material is disposed on at least one of: at least a portion of the cavity on the second surface, at least a portion of the cavity on the third surface, at least a portion of the first surface, and at least a portion of the fourth surface.

Abstract: The present invention relates to a stator of an electric machine with a stator body having a stator axis, which stator body comprises stator grooves in which there runs an electric plug-in winding which is formed from multiple conductor elements (4), conductor elements (4) being provided which each run with conductor branches through one or two of the stator grooves and protrude from the stator grooves on at least one end face of the stator by means of conductor ends (4b) and form a winding head, the conductor ends (4b) of the conductor elements (4) being arranged in the corresponding winding head in a plurality of groups (7) distributed in the circumferential direction in relation to the stator axis, each group (7) comprising a plurality of conductor ends (4b) arranged in a radial direction in relation to the stator axis, in particular aligned in the radial direction, characterized in that at least one, in particular a plurality, of the conductor ends (4b) of each group (7), as viewed in the radial direction