36results about How to "Weak noise" patented technology

An ultra-sensitive optical detector with large time resolution, using a surface plasmon. The optical detector is configured to detect at least one photon, and including a dielectric substrate, and on the substrate, at least one bolometric detection component, that generates an electrical signal from the energy of received photon(s). Additionally, at least one coupling component is formed on the substrate, distinct from the detection component and including a metal component, and generates a surface plasmon by interaction with the photon(s) and guiding the plasmon right up to the detection component, which then absorbs the energy of the surface plasmon.

A synthetic aperture photoplethysmography (PPG) sensor is disclosed. A group or matrix of contiguous PPG sensors located on a toilet seat are conditionally combined based on sensor measurements. Conditional combinations may be based on timing data and signal-to-noise ratio data of each of the PPG measurements. Measurements associated with the conditional combinations are then used to determine a cardiac function of a toilet user.

To provide a noise suppressing device which accurately suppresses weak electric field strength pulse noise.

A band-limiting unit (5) band-limits a composite signal obtained by demodulating an FM baseband signal, to a frequency band equal to or lower than a predetermined frequency so as to output a monaural audio signal. A pulse detecting unit (62) which detects pulse noise in the audio signal outputted by the band-limiting unit (5). A pulse judging unit (63) judges that a detection result of the pulse detecting unit (62) is valid in the case where pulse noise is detected in the composite signal, at a position corresponding to the detected pulse noise. A pulse suppressing unit (64) suppresses the pulse noise detected in the audio signal, in the case where the pulse judging unit (63) judges that the detection result is valid. Specifically, the amplitude of the composite signal which is synchronized with the audio signal is compared with a threshold, and it is judged that the detection result is pulse noise in the case where the amplitude of the composite signal exceeds the threshold.

The invention provides an energy-saving concrete vibrating tamper which comprises a vibrating bar. The vibrating bar comprises a shell and an internal structure. The internal structure comprises a spiral tube extending along the axis of the vibrating bar. The head portions of two screw tubes in the spiral tube are connected through a smooth guide tube, and the tails of the two screw tubes are also connected through a smooth guide tube, so that a smooth circulation channel is formed inside the spiral tube, wherein the two screw tubes are twisted in parallel, and a steel ball is arranged in the smooth circulation channel. The two ends of the spiral tube are each provided with an electromagnet. The electromagnets are coupled to a control module in the shell. The control module is connected with an external power source through a cable. The spiral tube, the electromagnets and the control module are fixedly connected with the shell. The two ends of the spiral tube are provided with position sensors coupled to the control module. When one position sensor senses that the steel ball reaches the end, where the position sensor is located, of the spiral tube, the control module switches off the corresponding electromagnet at the end of the spiral tube, and the electromagnet at the other end of the spiral tube is switched on. The energy-saving concrete vibrating tamper is low in cost, small in energy consumption and low in noise, and has a good vibrating effect.

The invention discloses a PVC-gel film preparation method, a PVC-gel film flapping wing flying mechanism and a preparation method thereof. The PVC-gel film flapping wing flying mechanism comprises flapping wings and a silicone rubber skeleton, wherein the flapping wings are made of a PVC-gel film, a positive electrode and a negative electrode are correspondingly arranged on the upper and lower parts of the PVC-gel film, the PVC-gel film is disposed on the silicone rubber skeleton in a penetrating mode to form a flexible flapping wing flying mechanism, and a square-wave voltage is applied to the positive electrode and the negative electrode to adjust the flapping frequency of the flapping wings. The structure is simple, the controllability is high, the flapping frequency is controllable, and by applying the square-wave voltage to the positive pole and the negative pole to adjust the flapping frequency of the flapping wings, no noise is generated substantially during the power-on process.

The invention discloses a noise reduction type forging hammer. The noise reduction type forging hammer is characterized by comprising a lower machine base, an upper mold, anvils, a connecting seat, aplurality of hammer heads, a plurality of active noise reducing devices and a plurality of guiding columns; one end of each guiding column is fixedly connected to the upper surface of the lower machine base, and the other end of each guide column is located in a guide column hole formed in the upper mold; one end of each hammer head is fixedly connected to the lower surface of the upper mold; theanvils are located below the hammer heads and are fixedly connected with the upper surface of the lower machine base, and mold holes are formed in the anvils; the connecting seat is fixedly connectedwith the upper surface of the upper mold; the multiple active noise reducing devices are connected with the lower machine base and are used for reducing the noise during forging hammer punching. Through the guide columns and the upper mold, the hammer heads have a good guiding effect in the stamping process; and meanwhile, the active noise reducing devices are adopted, and therefore diffusion of noise can be effectively reduced, the noise pollution generated in the stamping process is reduced.

The invention provides a simple heat exchanger for an outdoor unit of an air conditioner. The simple heat exchanger comprises a heat exchanging copper pipe, wherein an inner impeller of which a rotating plane is orthogonal to an axis of the heat exchanging copper pipe is connected in series with the heat exchanging copper pipe; an outer rotating wheel, which is arranged around the heat exchanging copper pipe and corresponds to the inner impeller, is arranged at the outer part of the heat exchanging copper pipe; when rotating, the outer rotating wheel can generate air flow close to the heat exchanging copper pipe; the inner impeller and the outer rotating wheel are coupled through a coupling mechanism, so that the inner impeller can drive the outer rotating wheel to rotate. The heat exchanger is free of a heat exchange fan and cooling fins, so that the size is simple and small, the working noise is low, and moreover, the heat exchanging performance is high.

A time-to-digital converter is provided. The time-to-digital converter comprises an oscillator controller, an invertible oscillator and a measurement circuit. The oscillator controller receives a start signal and a stop signal and outputs a mode signal. The invertible oscillator is electrically connected with the oscillator controller for receiving the mode signal. The oscillation direction of the invertible oscillator is inverted according to the mode signal, and the invertible oscillator outputs plural delay signals. The measurement circuit is electrically connected with the invertible oscillator for receiving the plural delay signals. The measurement circuit receives a sampling signal, samples the plural delay signals in accordance with the sampling signal, and outputs an output signal.

The invention discloses a fan blade which comprises a hub (110), a fan leaf (120) installed on the hub (110) and a diversion part (130) installed on the hub (110), wherein the diversion part (130) is arranged in the rotational center region of the hub (110); the outer surface of the diversion part (130) is provided with a barrier surface (131); and the barrier surface (131) blocks in a track of gas flowing toward the rotational center region of the hub (110). According to the fan blade, when the fan blade rotates, the rotational center region of the hub has a tendency of forming a negative pressure region; with arrangement of the diversion part, when flowing toward the rotational center region, the gas can be blocked by the barrier surface, so that the quantity of the gas which enters the rotational center region of the hub is lowered to some extent, collision of the gas and an ambient high-speed gas flow after the gas enters the rotational center region of the hub is relieved, and therefore, the produced noise is weaker when the fan blade runs. The invention also discloses an air conditioner.

An air purification device, including: a main body, a frame, a wind wheel holder, and wind wheels. The frame is disposed outside the main body. Air outlet grids are disposed on two sides of the frame. The main body is connected to the wind wheel holder. Wind wheel mounting slots are disposed on the wind wheel holder, and the wind wheels are mounted in the wind wheel mounting slots or in the wind wheel holder. The wind channels disposed on the wind wheel holder correspond to the wind wheels. A plurality of air inlets is disposed on the main body. A plurality of air outlets is disposed on the frame.

The invention discloses a low-noise weak signal acquisition circuit system, and the system comprises a low-noise variable gain amplification circuit, a driving module, an adjustable active band-pass filtering network, a startup and shutdown noise reduction circuit, a power amplification module and an anti-distortion detection circuit. Aiming at the defects that weak and small signals are weak in signal driving capability, high in signal processing difficulty, easy to introduce noise in a signal processing process and the like, a variable gain amplification circuit and an anti-distortion detection circuit based on a chopping technology are adopted to adaptively improve the signal amplitude (mV magnitude), and the frequency spectrums of the signals and the noise of the amplifier are separated; a second-order adjustable active band-pass filter network is adopted to separate useful signals from noise, and the bandwidth and gain of the filter network can be flexibly adjusted; in addition, a power-on and power-off noise reduction circuit is adopted to perform power-on and power-off noise reduction on the power amplification module, and finally the whole circuit system outputs analog signals which are low in noise, high in driving capacity, certain in voltage amplitude and free of distortion.

When a sheet jams in an image forming machine with a detachable unit having at least the image carrier device, it is necessary to detach the unit to remove the sheet when the image carrier device is charged with electric charge. When the unit is detached and re-attached, spark discharging may occur inducing noise upon the contact of an electrically conductive shaft of the image carrier device to a ground conductor. The present invention prevents the occurrence of such a problem. Guide grooves are provided to the base frames of the image forming machine to guide both end parts of the electrically conductive shaft of the image carrier device to position the unit in place, and a charge eliminating member is provided upstream from the position for allowing the electric charge accumulated on the image carrier device to be corona-discharged by way of the conductive shaft to remove the accumulated charge.