44results about How to "Improve noise quality" patented technology

A high frequency signal transmission apparatus includes a transmitter for transmitting received signals from a signal source as a modulated signal on a high frequency 900 MHz carrier to a remote receiver. The remote receiver converts the high frequency carrier in at least one conversion step to a lower frequency carrier signal. The lower frequency carrier signal carrying the modulated signal is then converted to another carrier signal and retransmitted as a modulated second signal to another remote receiver capable of demodulating the signal and broadcasting the audio sounds or video images. The oscillators in the transmitter and receiver are selectable to operate at discrete frequencies. Automatic fine tuning control is provided in the receiver to accommodate drift of the oscillator in the receiver. A recorder is coupled to the receiver for temporarily storing a demodulated first signal from the transmitter and then outputting the stored signals to a second transmitter for retransmission to a remote output device.

The invention provides a method for determining a noise reference signal for noise compensation and/or noise reduction. A first audio signal on a first signal path and a second audio signal on a second signal path are received. The first audio signal is filtered using a first adaptive filter to obtain a first filtered audio signal. The second audio signal is filtered using a second adaptive filter to obtain a second filtered audio signal. The first and the second filtered audio signal are combined to obtain the noise reference signal. The first and the second adaptive filter are adapted such as to minimize a wanted signal component in the noise reference signal.

Blades of an impeller for a centrifugal blower are resinous hollow blades having hollow spaces formed in the blade interiors, and having first blade weld parts welded to plate weld surfaces of an end plate, wherein first blade weld surfaces inclined with respect to the plate weld surfaces are formed on the first blade weld parts in a state in which the first blade weld parts are disposed to face the plate weld surfaces in the axial direction.

The invention provides a control method and control device of air conditioner and a computer readable storage medium. The air conditioner comprises an indoor unit and a compressor; the control method of the air conditioner comprises the steps of receiving an instruction capable of enabling the draught fan rotating speed of the indoor unit to be reduced to the second rotating speed from the first rotating speed; controlling the frequency of the compressor so as to enable the frequency to be reduced to the target frequency; gradually reducing the draught fan rotating speed of the indoor unit in the process of controlling the frequency of the compressor to be reduced to the target frequency, and therefore when the duration of running of the compressor under the target frequency reaches the preset time, reducing the draught fan rotating speed of the indoor unit to the second rotating speed. Through the technical scheme, when a windshield is adjusted, the noise quality can be improved, the use experience of a user can be improved.

The present invention discloses a rotary compressor and refrigeration equipment containing the rotary compressor. According to the rotary compressor, a lubricating oil and a refrigerant are packaged in the housing of the rotary compressor, the rotary compressor comprises a motor and a compression assembly, the compression assembly comprises a gas cylinder, an upper bearing, a lower bearing, a piston, a sliding sheet, and a crankshaft, at least one selected from the gas cylinder, the upper bearing, the lower bearing, the piston, the sliding sheet and the crankshaft is made from a damping alloy, and the specific damping value of the damping alloy is not less than 10. According to the present invention, the compression assembly of the rotary compressor has a high damping performance so as to minimize the noise vibration of the compressor body, such that the noise quality of the refrigeration equipment can be improved.

The noise reduction for signals which can contain speech at least part of the time is to be improved. To this end a hearing apparatus and especially a hearing device with a first estimation device for estimating a first value of an input signal with a first estimation algorithm and a noise reduction device for reducing noise in the input signal are provided. A second estimation device, which is parameterized with the estimated first value, is used for estimating a second value of the input signal with a second estimation algorithm. The noise reduction device receives the estimated second value from the second estimation device for reducing the noise. The two-stage estimation method enables an adaptive estimation to be carried out which is always currently adapted to an input signal.

The invention discloses an axial flow fan blade and an air conditioner provided with the same. The axial flow fan blade comprises a hub and multiple blade bodies arranged in the axial direction of the hub. Each blade body comprises a front edge and a tail edge, a tail wing is additionally arranged on the outer side of each tail edge, the edge of the outer side of each tail wing protrudes backward relative to the corresponding tail edge, the outline of the edge of the outer side of each tail wing is in a smooth curve shape, the radius of each blade body is defined to be R, the distance from the starting point A of each tail wing to the axial center O of the hub is R1, the distance between the finishing point B of each tail wing to the axial center O of the hub is R2, the ratio of R1 to R ranges from 0.70 to 0.88, and the ratio of R2 to R ranges from 0.96 to 1.00. By means of the axial flow fan blade, the tail wings are additionally arranged on the tail edges, so that the area of the fan blade is increased. Through design of the shapes and the positions of the tail wings, performance and efficiency of the fan blade are improved, and meanwhile noise of the fan blade is lowered.

The invention discloses a volute and a fan comprising the volute. The volute comprises a volute outer wall (1), and a volute inner wall (2) which is arranged on the volute outer wall (1) in a sleeve way and forms a sound-absorbing cavity (3) together with the volute outer wall (1), wherein sound-absorbing holes (4) are formed in the volute inner wall (2), and communicate the sound-absorbing cavity (3) with a volute inner cavity (6). According to the volute, the problem of high fan effluent noise in the prior art can be solved.

The invention discloses a multi-unit system and a control method of a heating indoor unit thereof. The method comprises the following steps: a shunt device obtains the target opening and the target duration of a throttling element in an indoor unit according to a preset opening and duration table if the indoor unit which is not started or at a refrigeration mode receives heating mode commands when the multi-unit system is at a pure refrigeration mode or a main refrigeration mode, controls the throttling element in the indoor unit to be opened to the target opening to adjust the pressure in front and rear of the throttling element, and adjusts the opening of the throttling element to the maximum opening when the target opening is operated for the target duration; a refrigeration control valve corresponding to the indoor unit is controlled to be closed after time is delayed by a first preset time; a corresponding heating control valve is controlled to be opened after time is delayed by a second preset time. The method avoids scouring noise produced when refrigerant flows rapidly and the influence on the refrigeration capacity of other indoor units by performing pressure equalizing on the indoor unit receiving the heating mode commands.

A conveying member, especially a rotor or stator, for conveying a flowable, preferably gaseous medium, comprises a plurality of blades (S1-S7) arranged following each other with a circumferential distance in a circumferential direction (U) around a central axis (A). Either a first circumferential distance (a) or a second circumferential distance (b) differing from the first circumferential distance (a) is provided between a blade and a respective blade following it in the circumferential direction (U) in a group of blades directly following each other in a circumferential direction (U), which the group comprises at least some of the blades (S1-S7). The first circumferential distance (a) is provided between at least two blades (S1-S7) located directly adjacent to one another, and the second circumferential distance is provided between at least two blades (S1-S7) located directly adjacent to one another.

The invention provides a ceiling-type air conditioner indoor unit. The ceiling-type air conditioner indoor unit includes a shell, a heat exchanger and a laminar flow fan; the upper part of the side surface of the shell is provided with at least one air inlet, and the lower part of the side surface of the shell is provided with at least one air outlet; the heat exchanger is arranged in the shell with the rotation axis extending vertically; and the laminar flow fan is located under the heat exchanger. When the laminar flow fan runs, the laminar flow fan prompts the indoor air to enter the spaceabove the heat exchanger from the air inlet, and then flow downward through the heat exchanger to exchange heat with the heat exchanger to form heat exchange wind; and then the heat exchange wind is blown back into the room through the air outlet. The ceiling-type air conditioner indoor unit provided by the invention realizes multi-directional and large-scale air supply, reduces the air supply noise, and improves the noise quality.

The invention discloses a fan assembly provided with a noise-reduction volute tongue and air conditioner. The fan assembly comprises a volute housing, a volute tongue, and a wind wheel which is arranged in the volute housing, wherein the distance A from the volute tongue to the outer edge of the wind wheel is subjected to at least preset variation trend in the axial direction of the wind wheel; the preset variation trend is that the distance A gradually increases, gradually decreases and gradually increases again; or the distance A gradually decreases, gradually increases and gradually decreases again. According to the technical scheme, the fan assembly effectively solves the problem that uniformly-spaced volute tongues in the prior art easily cause peak noise, resulting in loud running noise of a centrifugal fan.

The invention discloses a wing structure of a cross-flow fan. A pressure surface of a wing consists of two sections of arcs: an inner edge section and an outer edge section; a turning point is formedbetween the inner edge section and the outer edge section, and is formed at the peripheral end of a wing chord from a wing chord length by 27%; and the arc radius ratio value of the outer edge sectionand the inner edge section is 1: 1.35+-0.1. Through improvement of the structure, air currents firstly pass through 73% of the inner edge section during working; the pressing radius of the section islarger, the acting capacity is lower, and the buffering and rectifying effects are mainly achieved; the inner edge section is also called as a buffer section; then, the air currents pass through 27%of the outer edge section; the pressing radius of the section is lower, the acting capacity is higher, and main acting tasks are finished; the section is also call as an acting section; as an evaporator of an indoor unit of a conventional air conditioner adopts two rows of pipes, the overall resistance is lower; and as the cross-flow fan needs lower acting capacity, the buffer section of cross-flow blades can be enlarged as far as possible, the noise quality of the cross-flow fan is improved, and the practicability is high.

An ultraviolet-visible spectrophotometry (UV/Vis) high-performance liquid chromatography (HPLC) photometer includes a nano flow cell in which a light source feeds a reference light channel and a sample light channel, a reference photodiode for evaluating the reference light channel, and a sample photodiode for evaluating the sample light channel, which extends through the nano flow cell. To create a photometer whose signal evaluation is improved, respective effective exposure times of the sample photodiode and the reference photodiode are settable separately from one another.

The invention provides a combined suspended ceiling type air conditioner. The combined suspended ceiling type air conditioner comprises an outdoor unit provided with a condenser, a compressor and a throttling device, and a plurality of indoor units matched with the outdoor unit in parallel, an evaporator is arranged in each indoor unit, an air outlet of each indoor unit is positioned on the side surface of the indoor unit, the indoor units are hoisted on a roof, the side surfaces of the indoor units are detachably spliced, and the air outlets are exposed out so as to supply air indoors. According to the combined suspended ceiling type air conditioner, the refrigerating/heating capacity range can be expanded in a wide range according to user requirements, so that the comfort problem causedby the fact that the refrigerating/heating capacity is not matched with the user requirements and the loss caused by the replacement of an air conditioner are reduced.

The invention provides a ceiling-type air conditioner indoor unit. The ceiling-type air conditioner indoor unit comprises a shell, a heat exchanger, a fan and an air flue part; the shell is provided with one or more air inlets and one or more air outlets, and the air outlets are located in the side face of the shell; the heat exchanger is arranged in the shell; the fan is arranged in the shell andused for sucking indoor air through the air inlets to enable the indoor air to be subjected to heat exchange with the heat exchanger to form heat exchanged air, and blowing the heat exchanged air back into the indoor space through the air outlets; the air flue part is arranged in the shell, provided with one or more air flues in one-to-one correspondence to the one or more air outlets, and used for guiding the heat exchanged air to each air outlet; and the overflowing section at an inlet zone of each air flue is gradually decreased in the flowing direction of the heat exchanged air.