42results about How to "High vocal efficiency" patented technology

The invention relates to a key-press input module which comprises a motor vehicle horn key-press, a stabilivolt tube DW2, a resistance R3 and a resistance R4, wherein one end of the motor vehicle horn key-press is connected with the power output positive end or the power output negative end of a motor vehicle battery jar, the other end of the motor vehicle horn key-press is connected with a digital signal input end IN1 of a single chip microcomputer through the resistance R3, the digital signal input end IN1 of the single chip microcomputer is also connected with a digital signal output end O1 through the resistance R4 and also the cathode of the stabilivolt tube DW2, the anode of the stabilivolt tube DW2 is in grounding, and one end of the motor vehicle horn key-press is connected with the power output positive end or the power output negative end of the motor vehicle battery jar through a single-pole double-throw switch. The invention provides the key-press input module which has the advantages of simple structure and convenient use.

A thermal sounding device comprises a substrate, wherein the thermal sounding device further comprises at least one heating device and multiple thermal sounding elements, the multiple thermal sounding elements are respectively arranged on the substrate, the heating device is used for providing energy to the thermal sounding elements to enable the thermal sounding elements to produce heat, each thermal sounding element comprises a composite film, and the composite film comprises at least one carbon nano tube layer and at least one graphene film with the carbon nano tube layer and the graphene film being stacked over each other. The invention further provides an electronic device using the thermal sounding device.

The invention relates to a miniature dual-drive broadband signal sounder of an automobile. The miniature dual-drive broadband signal sounder comprises two drivers. The two drivers share a bottom board and a plastic housing arranged on the bottom board, two cavities which are bilaterally symmetrical with each other are formed between the bottom board and the plastic housing, circuit boards, iron cores, coils, magnetic rings, membranes and mass slices are arranged in the cavities, the iron cores are arranged on the circuit boards, the coils are wound on the iron cores, the magnetic rings are arranged on the iron cores, the membranes are supported by the magnetic rings, the mass slices are arranged on the membranes, front cavities are formed between the plastic housing and the membranes, inner cavities are formed between the membranes and the iron cores, rear cavities are formed between the circuit boards and the bottom board, through holes are formed in the iron cores and the circuit boards, the inner cavities are communicated with the rear cavities via the through holes, and two sound production holes which are bilaterally symmetrical with each other are formed in the center of the upper wall of the plastic housing. The miniature dual-drive broadband signal sounder has the advantages that the miniature dual-drive broadband signal sounder is provided with the two drivers, the rear cavities are communicated with the inner cavities, accordingly, different frequencies can be generated by the signal sounder, the response frequency range of the signal sounder can be greatly broadened, the sound production efficiency of the signal sounder can be greatly improved, the transmitted sound volume of the signal sounder can be greatly increased, and the service range of the signal sounder can be extended.

The invention relates to a power amplification circuit for a thermally induced sound-producing device, which comprises a peak holding circuit, an addition and subtraction circuit and a power amplifier. The peak holding circuit is used for receiving an audio electrical signal and outputting a peak holding signal; the addition and subtraction circuit is used for receiving the audio electrical signal and the peak holding signal, comparing the audio electrical signal and the peak holding signal, carrying out calculation and then outputting a modulation signal; and the power amplifier is used for receiving the modulation signal and amplifying and outputting the modulation signal. The invention also relates to the peak holding circuit and the thermally induced sound-producing device.