4results about How to "Guaranteed noise" patented technology

The invention discloses a range hood which comprises an exhaust fume collecting hood and a fan system, the fan system further comprises an upper air inlet, a lower air inlet, an exhaust fume collecting hood, an exhaust fume collecting hood and an exhaust fume collecting hood, and the upper air inlet is formed in a shell of the fan system, penetrates through the shell of the fan system and is communicated with the air inlet end of a fan of the fan system; the flow guide cover is arranged in the upper air inlet in a penetrating manner, an outlet of the flow guide cover corresponds to a fan air inlet end of the fan system, the flow guide cover extends in the height direction of the range hood, and an inlet of the flow guide cover extends outwards from a shell of the fan system; the driving part is arranged on the shell and used for driving the flow guide cover to do reciprocating motion in the height direction of the extractor hood, the calculation formula of the ratio coefficient of the flow of the upper air inlet to the total flow of the extractor hood is shown in the specification, delta is the ratio of the flow of the upper air inlet to the total flow of the extractor hood, and delta is the ratio of the flow of the upper air inlet to the total flow of the extractor hood. S is the stroke of the inlet of the flow guide cover in the height direction of the range hood.

This utility model relates to the field of bearing processing technology and discloses a drilling device for bearing production. The device includes a body assembly and a support plate. The top of the support plate has a moving groove, and the outer periphery of the top of the support plate has an installation groove. This utility model uses three circumferentially distributed adjusting components and a double-sided gear linkage mechanism to synchronously drive multiple clamping parts to move radially, achieving precise concentric clamping of the inner and outer rings of bearings of different diameters. The transmission structure of the lead screw and the driven bevel gear ensures consistent displacement of each clamping part. Combined with the rubber anti-slip texture design, it effectively prevents bearing slippage and reduces surface damage during clamping. The dual positioning mechanism of the positioning plate and the clamping plate further ensures strict concentricity of the inner and outer rings, significantly improving the drilling position accuracy, effectively reducing vibration and noise problems caused by eccentricity, and extending the service life of the bearing.

The utility model provides an anti-seismic structure of an automobile interior drawer, which belongs to the technical field of vehicle-mounted drawers and aims to solve the problems that plastic materials are short in service life due to abrasion in the use process, noise is easy to generate and user experience is affected if a gap between a drawer box and a panel is increased, and the anti-seismic structure comprises a mounting main body and a box body arranged in the mounting main body in a sliding manner, a plurality of mounting holes are formed in the mounting main body, anti-shaking assemblies are arranged in the mounting holes in a penetrating manner, each anti-shaking assembly comprises a main shaft clamped in the corresponding mounting hole, a ball head is arranged at one end of each main shaft, a tail part is arranged at the other end of each main shaft, a clamping cone is arranged between each tail part and the corresponding main shaft, the clamping cones abut against the mounting main body, and the ball heads are hemispherical and clamped between the mounting main body and the box body.

The application claims a high-gain operational amplifier circuit for Sigma-Delta ADC. The circuit comprises a main operational amplifier, a gain-improving auxiliary operational amplifier, a bias circuit and a switched-capacitor common-mode negative feedback circuit. The main operational amplifier serves as the main body of the circuit, has a high gain and a wide bandwidth; the auxiliary operational amplifier improves the output impedance and effectively improves the DC gain of the operational amplifier; the bias circuit is used to provide appropriate DC bias voltage for the main operational amplifier and the auxiliary operational amplifier; the switched-capacitor common-mode negative feedback is used to stabilize the output common-mode voltage. The application uses the auxiliary operational amplifier to improve the gain, ensures a high input-output swing of the operational amplifier, improves the DC gain of the operational amplifier, adopts a symmetrical switched-capacitor common-mode negative feedback, ensures the bandwidth range and reduces the nonlinearity of the circuit.