7results about How to "Lower natural frequency" patented technology

This invention relates to the field of blade processing equipment technology, and more particularly to a multi-axis rotary polishing machine tool for processing steam turbine blades, comprising: a frame, a grinding wheel base, a mounting shaft, and a clamping seat; the mounting shaft is rotatably connected to the frame; the clamping seat is rotatably connected to the mounting shaft; the grinding wheel base is connected to the frame; the support mechanism can clamp the blade and perform polishing on the blade's fluttering parts, thereby increasing the stiffness of the blade at the clamped part, and thus increasing the blade's natural frequency and eliminating flutter; this invention improves the stiffness of the polished part of the blade edge by clamping the clamping shaft on both sides of the thinner part of the blade edge during polishing, thereby increasing the natural frequency of that part of the blade, so that the natural frequency of the blade at the polished part is offset from the high-frequency vibration frequency generated by the rapid rotation of the grinding wheel base during polishing, thereby reducing the occurrence of flutter during polishing.

This application belongs to the field of valve technology, specifically relating to a pressure reducing valve and a fuel cell vehicle. The pressure reducing valve includes an inlet connector and a gas outlet; a primary pressure reducing assembly includes a primary pressure reducing valve body and a primary pressure reducing component, the primary pressure reducing component being inserted into the primary pressure reducing valve body. The primary pressure reducing component includes a primary pressure reducing section, with the gas outlet portion of the inlet connector inserted into the primary pressure reducing valve body, and the primary pressure reducing section and the gas outlet being positioned opposite each other. In a first direction, the cross-sectional area of ​​the primary pressure reducing section gradually decreases in a second direction, and the first direction intersects the second direction. This solution, through the primary pressure reducing section, can reduce the noise generated during gas pressure reduction, improving the vehicle's noise, vibration, and acoustic roughness characteristics.

The application provides a kind of stator core and motor.The stator core includes: first punching unit, the first punching unit includes first tooth part and first yoke part, one connecting joint is formed at the two ends of the first yoke part respectively, and the first punching unit is a symmetrical structure about the center line of the first tooth part;Second punching unit, the second punching unit includes second tooth part and second yoke part, and the second punching unit is a symmetrical structure about the center line of the second tooth part;Multiple first punching units and second punching units are arranged, multiple first punching units and second punching units are staggered and stacked, and two connecting joints axially adjacent can be rotatably connected to form a chain structure, and the chain structure is connected at the head to form the stator core.The application can reduce resonance and noise problems when the motor is running.

The invention provides a vehicle vibration energy collection device based on piezoelectric effect and nonlinear magnetic coupling and a design method, and belongs to the technical field of vibration energy recovery and automobile energy conservation. The device comprises a shell, a suspension spiral spring, a plurality of cantilever beams, a first permanent magnet and a second permanent magnet, the roots of the cantilever beams are fixed to the inner wall of the shell, the first permanent magnet and the second permanent magnet are fixed to the free ends of the cantilever beams and the suspension spiral spring respectively, and a gap is reserved between the first permanent magnet and the second permanent magnet; and a piezoelectric ceramic piece is arranged on the cantilever beam. The inherent frequency of the energy collection system is effectively reduced through magnetic coupling and mass block loading, efficient matching with the low-frequency vibration environment of the vehicle suspension is achieved, the initial horizontal gap between the first permanent magnet set and the second permanent magnet set is accurately set, the energy recovery efficiency is remarkably improved, and the energy recovery efficiency is improved. And power can be supplied to low-power-consumption vehicle-mounted electronic equipment.

The application discloses a stiffness and damping adjustable vibration isolator and relates to the technical field of vibration isolation devices.The vibration isolator comprises a load platform, a foundation platform, a damping device, a positive stiffness component and a negative stiffness component.The foundation platform is arranged below the load platform, the stiffness component and the damping device are arranged between the foundation platform and the load platform, two working ends of the damping device, the positive stiffness component and the negative stiffness component are respectively connected with the load platform and the foundation platform, the stiffness of the positive stiffness component and the negative stiffness component is adjustable, the damping device can change the damping by changing the current size of the wire on the damping device, the vibration isolator can adjust the positive stiffness, the negative stiffness and the damping, and has a wide application range.

The application relates to a dielectric elastomer-based active-passive integrated vibration isolator, mainly comprising a quasi-zero stiffness vibration isolation part (1), a vibration active control part (2), a guide shaft (3) and a spring supporting base (4), wherein the quasi-zero stiffness vibration isolation part (1) comprises a nonlinear stiffness element supporting spring (10), a nonlinear stiffness element (11) and a stop piece (12); the vibration active control part (2) comprises a dielectric elastomer supporting spring (20) and a dielectric elastomer (23) fixed between a dielectric elastomer fixed inner frame (21) and a dielectric elastomer fixed outer frame (22). Compared with the prior art, the application has the advantages that a lower inherent frequency can be obtained through the combination of positive and negative stiffness, meanwhile, a larger bearing capacity is achieved; the dielectric elastomer (23) is combined with a linear spring, so that the stress and strain are larger; a larger bandwidth of disturbance can be isolated through active-passive integration, and different external excitations can be adapted.

This invention discloses a vibration isolation device, relating to the field of vibration isolation control. It comprises a first-level passive vibration isolation unit consisting of a lower plate and lower elastic supports, a middle plate, an inertial reaction force vibration suppression module, and an upper elastic supports, forming a second-level vibration isolation unit. The inertial reaction force vibration suppression module consists of an actuator, a mass block, and quasi-zero stiffness legs. Sensors for acquiring external vibrations and outputting feedback signals are installed on the middle plate. A controller receives the feedback signals and sends action commands to the actuator. The vibration isolation device provided by this invention employs a dual-layer dynamic architecture, deeply integrating a magnetic quasi-zero stiffness mechanism with electromagnetic active control. It aims to completely eliminate the dependence of traditional quasi-zero stiffness systems on the weight of specific equipment, achieve efficient blocking of excitation forces across the entire frequency band under broad loads, and fundamentally solve the problem of dynamic instability in the resonance region of the system.