40results about How to "Stiffness controllable" patented technology

A damping-rigidness-controllable double-freedom-degree vibration active control platform comprises a cross-shaped beam frame and a square base which are connected through a flexible hinge. A cross-shaped beam of the cross-shaped beam frame is distributed in the diagonal directions of the square base. A structure column is arranged at the center of the cross-shaped beam frame. Sensors and actuators are connected between the lower portions of the diagonal top ends of the cross-shaped beam frame and the square base respectively. Four limiting columns are arranged between the cross-shaped beam of the cross-shaped beam frame and the square base respectively. Prearranged gaps are reserved between the limiting columns and the cross-shaped beam frame. Four balancing weights are fixed on the lower portion of the cross-shaped beam frame between the sensors or the actuators and the limiting columns respectively. Twisting limiting spring pieces are arranged at the symmetrical positions on the lower portion of the cross-shaped beam frame between the limiting columns and the flexible hinge. The electromagnetic type sensors and the electric-damping electric-rigidness actuators are used to achieve detecting of angular speed and actuating, the flexible hinge and the spring piece with changeable thickness are combined to achieve controllable damping and rigidness in a quantifying mode, and double-freedom-degree vibration active control in the x direction and the y direction of the structure is achieved.

The invention discloses a variable rigidity vibration isolator based on multi-layer dielectric elastomer films. The vibration isolator comprises a multi-layer dielectric elastomer film spring and a plurality of annular magnets. The multi-layer dielectric elastomer film spring is formed by overlapping the multi-layer dielectric elastomer films and multiple conductive electrodes, and the polaritiesof the adjacent conductive electrodes are opposite. The vibration isolator realizes the non-linear negative stiffness through non-linear restoring force generated by the mutually attracted annular magnets. By changing driving voltage applied to the conductive electrodes of the multi-layer dielectric elastomer film spring, the multi-layer dielectric elastomer film spring is made to provide the positive stiffness matched with the driving voltage. Quasi-zero stiffness nearby the working position is realized through combination of the negative stiffness and the negative stiffness, and the inherentfrequency of a vibration isolation system is effectively reduced. As the multi-layer dielectric elastomer film spring provides the positive stiffness for voltage adjustment and control, the defect that the stiffness adjustment and control capacity of a single-layer dielectric elastomer film is limited is overcome, the stiffness adjustable and controllable range is greatly expanded, and adjustmentand control over the stiffness is realized.

The invention provides a negative-stiffness-adjustable torsional quasi-zero stiffness vibration isolator and a control method. The negative-stiffness-adjustable torsional quasi-zero stiffness vibration isolator comprises a front shell, a rear shell, a front washer, a rear washer, a rotary sleeve used for fixing a transmission shaft, and a permanent magnet excitation mechanism. A rotary component of the permanent magnet excitation mechanism is fixedly connected with the rotary sleeve and is fixedly connected with a permanent magnet through a rubber pad. A magnetic flux generated by the permanent magnet passes through the rubber pad, the rotary component, an air gap and an annular permanent magnet clamping mechanism to return to the permanent magnet to form a magnetic flux loop, and the magnetic stress is generated in the air gap and is applied to the rotary component, so that a torsional magnetic spring is formed by the rotary component in the thickness direction of the air gap. The magnetic field intensity in the air gap is changed by adjusting the intensity of current supplied to an exciting coil, and then the negative stiffness of the magnetic spring is changed to be close to thepositive stiffness achieved through a rubber bearing, so that the system stiffness is made to the quasi-zero state. The negative-stiffness-adjustable torsional quasi-zero stiffness vibration isolatorcan effectively transmit the driving torque and can isolate the disturbance torque; the system stiffness is actively controlled, so that low-frequency torsional vibration is well isolated; and the negative-stiffness-adjustable torsional quasi-zero stiffness vibration isolator is suitable for a precision rotating system.

The invention provides a combined air spring integrated with a coil spring with an additional air chamber with the adjustable volume. The combined air spring comprises an upper covering plate, a pouch leather, a lower covering plate, the additional air chamber, an additional air chamber piston, a piston rod and a linear stepper motor. The upper covering plate, the pouch leather and the lower covering plate form an air spring, and an air spring cavity of the pouch leather is filled of high-pressure air. The additional air chamber is mounted on the lower covering plate in the an air spring cavity and is in a cylindrical shape. The additional air chamber has an opening end and an enclosed end, and the enclosed end contacts with the lower covering plate. The center of the additional air chamber is located on the central connecting line of the upper covering plate and the lower covering plate. The additional air chamber is provided with the additional air chamber piston which is capable of performing reciprocating motions freely, and the additional air chamber piston is connected with the upper covering plate through the piston rod fixed on the additional air chamber piston. The effective volume of the additional air chamber is formed by the additional air chamber piston and the enclosed end of the additional air chamber.

The invention discloses an electromagnetic quasi-zero stiffness vibration isolation system based on the Stewart platform. The electromagnetic quasi-zero stiffness vibration isolation system based on the Stewart platform comprises an upper platform and a lower platform, the upper platform and the lower platform are oppositely arranged, six vibration isolation devices are arranged between the upperplatform and the lower platform, six vibration isolation devices are arranged according to a Stewart platform mode, a first diaphragm spring is arranged at one ends of the vibration isolation devicesin a sleeved mode, the other end of the vibration isolation device is sleeved with a second diaphragm spring, each vibration isolation device comprises a guide shaft, a magnet set is arranged on the outer side of the guide shaft, a coil set is arranged on the outer side of the magnet set, a gap is formed between the magnet set and the coil set, and an outer cylinder is arranged on the outer side of the coil set. According to the electromagnetic quasi-zero stiffness vibration isolation system, the adjustable nonlinear negative stiffness is realized by utilizing the mutual acting force between the permanent magnet and the conductive coil, the first diaphragm spring and the second diaphragm spring provide positive rigidity, and the quasi-zero rigidity near the working position is achieved through combination of positive and negative rigidity; the electromagnetic quasi-zero stiffness vibration isolation system has the advantages of being simple in structure, the rigidity is controllable and the like, the inherent frequency of the vibration isolation system is effectively reduced, and further the vibration isolation frequency band is widened.

The invention discloses a multi-stage energy consumption device for anti-seismic and vibration reduction of a building structure, which includes a base, a skeleton unit and a support plate, and is characterized in that: the steel skeleton of the device is composed of the several skeleton units, and the skeleton unit is composed of Composed of six plates of the same form, the interior of the plates is composed of rings, and four equal support rods protrude tangentially at equal intervals from the outside. The interior of the skeleton is filled with high-damping rubber, and the upper part of the steel skeleton is covered with a support plate. The device utilizes the composite properties of negative Poisson's ratio steel skeleton and high damping rubber. It is a vibration isolation and anti-seismic system with adjustable damping. Its stiffness can be controlled and damping can be adjusted, which is convenient for multi-level energy consumption design according to the dynamic performance of the structure. .

The invention discloses a damping device and an engine system, belonging to the technical field of damping. The shock absorbing device of the present invention includes a casing and a transmission shaft, the casing is used to connect with the rotating drive and the inner wall of the casing is provided with a plurality of internal convex teeth along the circumference; the transmission shaft is passed through the casing, and the outer wall of the transmission shaft is A plurality of outer convex teeth are arranged in the direction, and the outer convex teeth and the inner convex teeth are alternately distributed, and rubber shock absorbers are arranged between the adjacent outer convex teeth and the inner convex teeth. When the flywheel drives the casing to rotate, the inner convex teeth on the casing turn the drive shaft through the rubber shock absorber, and the drive shaft drives the subsequent transmission system to rotate. The elastic damping of the rubber shock absorber can change the rigid impact into elastic impact, Realize shock absorption; and the stiffness of the rubber shock absorber is easy to control, and the stiffness of the rubber shock absorber is smaller, which can more effectively consume the vibration energy in the form of heat energy, thereby suppressing torsional vibration and avoiding the vibration of the whole machine to the greatest extent. Natural frequency, good shock absorption effect.