A 1D ultrasonic transducer unit for detecting danger for a vehicle, comprising a housing mounted on the vehicle, which includes at least three discrete ultrasonic transducers, designed to decouple sound waves at a corresponding working frequency between 20 kHz and 400 kHz into a gaseous medium, and a control unit, designed to control each ultrasonic transducer individually, two ultrasonic transducers directly adjacent to each other in each case having a distance, the 1D ultrasonic transducer unit having one sound channel per ultrasonic transducer, each with one inlet opening assigned to exactly one ultrasonic transducer and one outlet opening (26), the outlet openings being arranged along a straight line, a distance from directly adjacent outlet openings corresponding to no more than the full or half wavelength in the gaseous medium and being shorter than the corresponding distance.

A 1D ultrasonic transducer unit for area monitoring, having a housing having a securing device for securing to a surface and having at least three discrete ultrasonic transducers designed to decouple sound waves with a consistent operating frequency between 20 kHz and 400 kHz in a gaseous medium, and a control unit designed to control each ultrasonic transducer individually, wherein two ultrasonic transducers, directly adjacent to one another, are spaced apart by a distance, the 1D ultrasonic transducer unit has a sound channel per ultrasonic transducer with an input opening, associated with exactly one respective ultrasonic transducer, and an output opening, the output openings are arranged along a straight line, a distance from the directly adjacent output opening corresponds at most to the full or half the wavelength in the gaseous medium and is smaller than the corresponding distance.

Road vehicle having: a passenger compartment; an internal combustion engine provided with at least one exhaust duct, which originates from an exhaust manifold and has at least one exhaust gas treatment device; and an exhaust noise transmission device provided with a transmission duct, which originates from the exhaust duct, and with a symposer device, which is arranged inside the transmission duct, is pneumatically insulating and is acoustically permeable; an inlet of the transmission duct being arranged between the exhaust manifold and the exhaust gas treatment device, hence upstream of the exhaust gas treatment device.

An earpiece is provided. The earpiece can deform flexibly so as to follow the earhole when in use, and the earpiece can be manufactured easily. An earpiece includes an earpiece body and a filler filled in the earpiece body. The earpiece body has a container-like base member formed of a rubber-like elastic diaphragm that is shaped like a container and has an opening portion. The earpiece body also has a lid member that seals the opening portion liquid-tightly. The filler is flowable at room temperature.

A method of designing an acoustic waveguide in which acoustic waves travelling along the waveguide are treated as exhibiting single parameter behaviour, and in which the waveguide provides a boundary confining the acoustic waves as they travel along the wave propagation path and has two substantially parallel, primary surfaces spaced apart a distance less than a wavelength of a high frequency acoustic wave. The primary surfaces may be planar, curved, or a combination of planar portions and curved portions.

A 1D ultrasonic converter unit having at least three ultrasonic converters and a control unit for individually controlling each ultrasonic converter, wherein each ultrasonic converter has a housing, a piezoelectric body, and a sound decoupling layer for decoupling sound waves in a gaseous medium, is embedded in a common carrier structure, and emits and/or receives the same frequency between 20 kHz and 400 kHz. The 1D ultrasonic converter unit one sound channel having an input opening associated with one sound decoupling layer, and an output opening. The output openings are arranged along a line, a distance between two adjacent output openings corresponds at most to the whole or half the wavelength of the sound frequency and is smaller than the distance of the input openings.

According to an embodiment of the invention, a sensor includes a first element part. The first element part includes a first member and a first element. The first member is tubular and extends along a first direction. The first member includes a first opening and a second opening. A direction from the second opening toward the first opening is along the first direction. The first element includes a vibratile first membrane, and a first supporter supporting the first membrane. The second opening is between the first opening and the first membrane in the first direction.

Described is a voice generation system. The voice generation system comprises a housing comprising a first opening and a second opening. The housing defines an air passage between the first opening and the second opening. The voice generation system comprises a moveable member located within the housing. The moveable member is configured to vibrate in response to air flowing in the air passage. The voice generation system comprises a transducer module configured to convert vibrations of the moveable member into an electrical signal. The voice generation system comprises a speaker module configured to convert the electrical signal into sound and to output sound into the oral cavity of a user. The voice generation system is configured such that during use, the air pressure at or near the second opening corresponds to an air pressure in the oral cavity of the user.

A vehicle comprising: an internal combustion engine having at least one cylinder, the internal combustion engine comprising an exhaust manifold for collecting exhaust gases expelled from the at least one cylinder; an exhaust system configured to channel exhaust gases along a flow path from the exhaust manifold to at least one exhaust outlet, the exhaust system comprising at least one exhaust component configured to act on exhaust gases flowing though the exhaust component and causing an alteration to engine-generated sound pulses passing through the exhaust component; and a sound bypass device comprising a sound inlet port at a first location on the exhaust system before a first exhaust component along the flow path and a sound outlet port at a second location on the exhaust system after the first exhaust component along the flow path, the sound bypass device being configured to transmit engine-generated sound pulses from the sound inlet port to the sound outlet port whilst preventing flow of exhaust gases from the sound inlet port to the sound outlet port.

A vehicle comprising: an internal combustion engine having at least one cylinder, the internal combustion engine comprising an exhaust manifold for collecting exhaust gases expelled from the at least one cylinder; an exhaust system configured to channel exhaust gases along a flow path from the exhaust manifold to at least one exhaust outlet, the exhaust system comprising at least one exhaust component configured to act on exhaust gases flowing though the exhaust component and causing an alteration to engine-generated sound pulses passing through the exhaust component; and a sound bypass device comprising a sound inlet port at a first location on the exhaust system before a first exhaust component along the flow path and a sound outlet port at a second location on the exhaust system after the first exhaust component along the flow path, the sound bypass device being configured to transmit engine-generated sound pulses from the sound inlet port to the sound outlet port whilst preventing flow of exhaust gases from the sound inlet port to the sound outlet port.