5results about How to "Reduce low frequency vibration" patented technology

The invention relates to the technical field of noise reduction, in particular to a sound insulation structure and sound insulation glass, comprising: a main body having a first surface which is recessed inwards to form a cavity; and the rebounding piece is arranged in the cavity and can reflect the sound waves entering the cavity from the first surface. The device has the beneficial effects that when low-frequency sound waves are transmitted and incident to the main body, the sound wave frequency is matched with the cavity frequency to cause air resonance in the cavity, air rushes into the cavity from the outside of the cavity, viscous loss can be generated between holes and the air, and sound wave energy is converted into heat energy to be weakened; the rebound piece in the cavity starts to vibrate due to the resonance effect, the acting force of the sound waves on the main body and the counter-acting force generated by vibration of the rebound piece offset each other, the vibration of the main body is weakened, and therefore the noise reduction effect on low and medium frequency noise is achieved.

The utility model relates to the technical field of landing gear, concretely relates to a landing gear damping mechanism. It includes stand, crossbeam, wheel frame and sets up the damping component between stand and crossbeam, and the damping component is constituted by outer tube, piston rod, piston head, honeycomb aluminium energy absorption module group and disc spring bag etc. Honeycomb aluminium energy absorption module group is at least two layers along the axial direction and is equipped with deformation joint between layers, and honeycomb aluminium energy absorption module group, disc spring bag and piston rod are arranged in outer tube from top to bottom, and the conical force transmission rod of piston rod top inserts the central hole of honeycomb aluminium energy absorption module group and forms the conical surface cooperation. The landing gear adopts the "hydraulic damping-honeycomb aluminium-disc spring" compound damping structure, and through honeycomb aluminium graded energy absorption, disc spring nonlinear elasticity and friction damping, hydraulic damping medium energy dissipation, effectively solve the problem of traditional landing gear energy absorption efficiency low, high frequency vibration attenuation deficiency, heavy load impact load concentration etc., and is suitable for high frequency impact and concentrated load working condition, and the damping effect is good.

The utility model discloses an inverted tower-type sound box with a sufficient noise reduction characteristic, which comprises a sound box main body and a hoisting piece arranged at the top of a cavity of the sound box main body, a damping frustum assembly for noise reduction is arranged at the bottom of the cavity, and the hoisting piece comprises a top plate arranged at the top end of the cavity and a hoisting hole formed in the top plate. Positioning columns are arranged at the corners of the top plate, the damping frustum assembly comprises a mounting base arranged at the bottom of the cavity and frustums which are sequentially and downwards connected in a conical sleeving mode from outside to inside from the mounting base, the bottoms of the frustums are attached to the mounting base, conical heads are arranged at the bottommost parts of the frustums, and conical tips are arranged at the bottom ends of the conical heads. According to the utility model, the problems of poor noise reduction effect and no hoisting structure of the inverted-phase sound box in the prior art are solved.

The utility model discloses a kind of muffler air inlet pipe connecting frame, relate to agricultural machinery technical field.The muffler air inlet pipe connecting frame, including base, the base upper fixedly connected with engine, engine side surface fixedly installed with support frame, support frame is fixedly installed with shell, shell upper and lower sides are fixedly installed with air outlet pipe and air inlet pipe and with shell interior intercommunication, engine side surface is equipped with exhaust port, support frame lower side fixedly connected with pipe support, fixedly installed with rubber pad between pipe support and air inlet pipe;Support frame front end lower side fixedly installed with shock-absorbing rod.The muffler air inlet pipe connecting frame, the shock-absorbing spring of the muffler air inlet pipe connecting frame's connecting support frame installation can effectively attenuate low-frequency vibration generated when engine operates, through elastic deformation absorption vibration energy, reduce the vibration transmission caused by rigid connection, avoid the problem that weld point cracks, component loosening etc.

The utility model discloses a wind noise resistant earphone, which comprises an earphone main body and a rod body connected with the earphone main body, the rod body is provided with a head end and a tail end, the head end is connected with the earphone main body, the tail end is provided with a sound pickup hole coupled with external acoustics, the tail end is detachably connected with a wind-proof piece, the wind-proof piece covers the sound pickup hole, and the head end is connected with the earphone main body. The windproof piece can be penetrated by sound; therefore, the wind noise resistance of the earphone can be effectively improved, the influence of wind noise is reduced, the pickup effect of the microphone is effectively improved, and the call quality in a wind noise environment is improved.