311 results about "Vibration Problem" patented technology

The invention relates to an acceleration or deceleration control method of numerical control system based on filter technique, which comprises the following steps: planning straight acceleration or deceleration by using the inputted workpiece program data; performing moving average filtering and filter compensation on the planned speed of the straight acceleration or deceleration to obtain a new planned speed value and a position value; performing interpolation on the position value; transmitting the interpolated position value to a servo driver in order to control a servomotor; wherein the moving average filtering of the planned speed of the straight acceleration or deceleration is implemented by adding a moving average filter after planning the straight acceleration or deceleration to control sudden changes of an accelerated speed, particularly comprising the following steps: calculating the speed with a method of planning the moving average filtering speed; changing the smooth degree of the straight acceleration or deceleration by selecting filter length (i.e. controlling the magnitude and the shape of the accelerated speed); and calculating a planned position according to the speed after filtering. The invention solves the vibration problem of a numerically-controlled machine tool during movement, and has the advantages of easy implementation, good compatibility and good flexibility.

The invention relates to the technical field of mechanical machining, in particular to a double-S-shaped double-curve thin-walled part manufacturing process. A five-coordinate high-speed mill is adopted to conduct rough machining on an inner curve and an outer curve with ribs and conduct semi-finish machining and finish machining on the inner curve and the outer curve with ribs, and a step cushion block positioning and gypsum filling method is adopted to perform clamping and positioning. The part clamping and positioning problems are solved, and part clamping stability and machining rigidity are improved. Regional segmented and layered machining is adopted for parts, machining deformation of ultra-complicated thin-walled curved surfaces is effectively controlled, the vibration problem in the machining process is avoided, and part size and accuracy are ensured.

A display device with a built-in touch screen according to the present disclosure includes a display panel, a data driver, a gate driver, a touch sensing unit, a common voltage supplier, and a switch circuit, and further includes a common voltage adjuster to supply different common voltages to touch electrodes of the display panel, thereby resolving a local stain or screen vibration problem occurring on the display panel. Further, a method for driving a display device with a built-in touch screen according to one embodiment includes: switching the display panel from a touch mode to a display mode, generating different common voltages, and supplying two or more of the different common voltages to a plurality of touch electrodes (TE) or groups of touch electrodes (TE), thereby resolving an image quality defect.

The invention discloses a vibration monitor and control method and system for a wind turbine generator. The method comprises a collection step, wherein cabin vibration signals of the wind turbine generator are obtained; a calculation step, wherein according to the cabin vibration signals, cabin vibration frequency values are calculated; an identification step, wherein according to calculated vibration frequency, an oscillation-actuating source is judged; a vibration reduction step, according to the oscillation-actuating source, an oscillation-actuating frequency in control signals are filtered out. The vibration monitor and control method and system for the wind turbine generator can thoroughly solve the cabin vibration problem caused by variable pitch adjusting, the transmission chain rotating frequency and the like, and any equipment cost is not required to be added.

The invention discloses a testing device for the test table which stimulates the motion of the bent-axle rotator-bearing system, and comprises a drive device comprising a motor and a reducer, a supporting device, a tested bent axle, a loading device and a signal measuring device. The invention has the advantages of being able to study the coupling action of the bent-axle rotator-bearing system dynamic behavior of high-power, low speed and semi-integrated marine diesel and the vibration problem when the bent axle rotating separately and being processed, which also can research the dynamics problem when working with a connecting prod and a piston; besides, through testing, the invention discloses the situation that the radial unbalanced quality pushing can lead to the coupling vibration of bent axle. The invention can help people to have more perfect understanding to the bent-axle rotator-bearing system and build more accurate correlative dependence relation among each design index for multi-cylinder diesel, which provides guidance on the theory of improving the performance of diesel further.

A multi-level micro-vibration system testing method and a system are provided; the method comprises the following steps: carding and classifying micro vibrations; building a related testing system according to different features of micro-vibration sources, and carrying out a single-machine level micro-vibration test so as to learn micro-vibration source features, or transmission features of a micro-vibration vibration isolator; building a sub-system micro-vibration testing system, developing a sub-system level micro-vibration test so as to learn about the micro-vibration source and boundary condition coupling features and micro-vibration system transmission features; building a system-level micro-vibration testing system, and developing a system-level micro-vibration test so as to learn about the micro-vibration influences on an optical system; finally using a satellite in-orbit test phase to develop a large system-level micro-vibration test, thus fully verifying micro-vibration related analysis and designs. The method fully considers various nodes affected by micro-vibration, can fully solve the micro-vibration problems, thus effectively preventing problems that a conventional method is single-machine, single-subject, and a local test cannot solve the system problems; the multi-level micro-vibration system testing method and system fill the technical blanks in related fields in our nation.

The invention discloses an automobile shock absorber and belongs to the field of automobiles. The automobile shock absorber is arranged inside an automobile steering wheel and comprises a mass block and a rubber column under the mass block, wherein the rubber column is used for supporting the mass block; and the mass block is fixedly connected with the rubber column, and the tangential inherent frequency of the automobile shock absorber is allowed to be close to the idle-speed vibration frequency of the automobile steering wheel so as to form resonance. The automobile shock absorber of the invention effectively utilizes the inner space of the steering wheel and the tangential stiffness property of rubber and adopts a shock absorbing structure comprising the mass block and the rubber column, so that a small-size and low-frequency power shock absorber is designed and manufactured, the idle-speed vibration problem of the steering wheel is solved, and the first application of shock absorber technology in solving the vibration problem of the idle-speed steering wheel in China is realized. Comparing with the prior art, the automobile shock absorber has the advantages of simple structure, simple and convenient processing and manufacturing, short development period, low cost and convenient popularization.

The invention discloses a flexible fixture for milling of a large complex surface type blade and a method of the flexible fixture. The flexible fixture and the method solve the processing vibration problem in a processing procedure of a complex surface thin-walled workpiece, the processing deformation of the thin-walled structure like a large blade can be reduced, and the vibration during processing can be reduced. The flexible fixture is characterized in that the flexible fixture comprises a lower clamping part arranged at a workbench; a flexible clamping part is arranged on the lower clamping part in a matched manner; the two ends of the flexible clamping part are connected with a horizontal movement mechanism; the end part of the horizontal movement mechanism is connected with a vertical movement mechanism; the flexible clamping part comprises an elastic clamping body flexibly bonded with the side wall of the blade; the elastic clamping body flexibly clamps the side wall of the upper part of the blade; the lower clamping part clamps the bottom of the blade; in a processing procedure, the horizontal movement mechanism and the vertical movement mechanism drives the elastic clamping body to adjust a position for clamping the blade, for reserving a to-be-processed area.

The invention provides a space robot collision avoidance method based on multiple control points. During path planning, the angular velocity of a joint of a mechanical arm is smooth, discontinuity of the angular velocity of the joint of the mechanical arm is avoided, and the vibration problem caused by jumping of a single control point can be restrained. The space robot collision avoidance method based on the multiple control points comprises the steps that (1) an obstacle is processed into a non-convex polyhedron composed of triangular faces, the mechanical arm is processed into line segments, the collision detection algorithm between the describing line segments and the describing triangles is determined, and a pair of control points, with the shortest distance, between the mechanical arm and the obstacle are obtained; (2) a multi-mask kinematical equation considering the collision avoidance tasks of the space robot is established; (3) the collision avoidance constraint conditions of the space robot are established, and collision avoidance solving is conducted through the combination with the kinematical equation in the step (2); (4) according to the parameter design of the multiple control points, the parameters of a new control point are adjusted, and collision avoidance solving is conducted through the combination with the kinematical equation in the (2); and (5) according to the collision avoidance solution, to one obstacle, of the multiple control points, multiple-obstacle collision avoidance control is conducted on the mechanical arm of the space robot.

The present invention provides a method operable to improve pressure recovery and / or distortion within engine inlet. This method involves providing a first fluid flow to primary jet vortex generator(s) operable to inject fluid at a first injection rate into a boundary layer of a primary fluid flow within the inlet. A secondary fluid flow is injected by secondary jet vortex generator(s) at a second injection rate into the boundary layer of the primary fluid flow. The fluid injected at the first injection rate and second injection rate is operable to induce secondary flow structures within the boundary layer. These secondary close structures are then operable to improve or manipulate the pressure recovery of the inlet. At specific engine conditions, this method may redistribute the ratio of the first injection rate and second injection rate in order to improve pressure recovery and / or distortion of the inlet when the particular engine conditions. Such engine conditions may be associated with a natural blade frequency of the engine at a particular speed. Embodiments of the invention allow blade vibration problems associated with engine operation at particular speeds to be solved without adding damping or increasing blade strength to change the natural frequency of the blades, thereby reducing weight and improving engine performance.

A vibration control experiment platform for an aero-engine comprises the components of an experiment platform base, an aero-engine body, a driving system, a testing control system and a security protecting device. A first driving motor of the driving system transmits a power to a low-pressure rotor system of the aero-engine body. A second driving motor transmits the power to a high-pressure rotor system of the aero-engine body through a second coupling and an accessory transmission system of the aero-engine body. A motor output shaft, the low-pressure rotor system and the high-pressure rotor system are provided with capacitive displacement sensors. A second-stage case, a third-stage case, a six-stage case, a combustion chamber case and a high-pressure turbo case which correspond with five supporting bearings of the aero-engine are provided with three-dimensional vibration acceleration sensors. The vibration control experiment platform can be used testing and analyzing a multi-factor coupled vibration problem of the aero-engine. The vibration control experiment platform can be widely used for researching vibration characteristic and vibration control strategy of an aero-engine double-rotor system.

The invention discloses an identification method for a sub-synchronous / super-synchronous coupling impedance (admittance) model of a power device. The identification method for the impedance model comprises the steps of providing the sub-synchronous / super-synchronous coupling impedance model of the power device; connecting the power device into a power grid, applying sub-synchronous / super-synchronous excitation to the power grid, and obtaining sub-synchronous and super-synchronous voltage components and current components of the power device based on the sub-synchronous / super-synchronous coupling impedance model; changing sub-synchronous / super-synchronous excitation parameters or parameters of an external power grid, thereby obtaining multiple groups of measurement results of the power device, and generating an impedance measurement equation according to the multiple groups of measurement results; and carrying out a preset numerical optimization method on the impedance measurement equation to obtain impedance parameters of the sub-synchronous / super-synchronous coupling impedance model. The method has the advantages that the indivisibility between complementary frequency dynamic states of two relatively working frequencies is represented, and the sub-synchronous / super-synchronous resonance and vibration problems of a power system are analyzed and explained well.

The invention relates to a magnetic field reconstruction method for eliminating torque pulsation of a doubly-fed induction motor. In order to eliminate the torque pulsation problem of the doubly-fed asynchronous induction motor caused by electric network voltage unbalance and electric network voltage harmonic waves to the greatest degree, the invention provides the motor magnetic field reconstruction method. On the basis of the structure, the dimension, the materials, the electric parameters and the like of the actual motor, Infolytica Magnet electromagnetic field simulation software is adopted for studying the torque generation from the motor magnetic field angle, and in addition, the unexpected torque pulsation is eliminated through the optimization on the rotor current. As an alternative excitation scheme, the method avoids the control precision problem caused by motor equivalent model inaccuracy. The magnetic field reconstruction method has the characteristics that the calculation speed is high, the torque pulsation elimination effect of the doubly-fed induction motor is obvious, and the like. The magnetic field reconstruction method can be used for solving the vibration problem of the doubly-fed induction motor for wind power generation caused by electric network voltage unbalance or electric network voltage harmonic waves.

An octahedral tank type steel purlin arc bridge boom relates to a structure that can solves the wind vibration problem of a long-span or extra long-span steel purlin arc bridge boom. The invention is in flat octahedral tank type structure and is formed by welding of a web plate, a wing plate and a slant angle plate; the boom is internally provided with a diaphragm plate, thus realizing vertical strengthening action; a stiffening rib is arranged between the web plate and the wing plate which are in correspondence, thus realizing transverse strengthening action; and the lower end is respectively connected with a bridge floor gusset plate and a web terminal plate by a high strength bolt and a splice plate while the upper end is connected with an arch chord gusset plate by a high strength bolt. The boom of a steel purlin arc bridge adopts the octahedral tank type boom, the rigidity of the boom is high, and pneumatic appearance is better, thus effectively solving the wind vibration problem of the long-span and extra long-span steel purlin arc bridge boom. The invention is tried out on Nanjing Dashengguan Yangtze River Bridge and has favourable effect.

The invention relates to a steam turbine generator iron loss test vibration and noise testing method. Acceleration sensors are installed at a steam turbine generator stator iron core pressing plate, a cross-core screw, a yoke part, a press finger part, a stator winding water box and an end ring part, and vibration signals are collected. Sound pressure sensors are installed with distances of one meter from a steam end and an exciter end, and noise signals are collected. The measurement is carried out through a dynamic signal analysis system, and then whether an iron core is pressed tightly and whether electromagnetic resonance exists at a winding end part are judged according to an analysis result. Through the application of the method, the vibration problems of the stator iron core and the winding end part can be solved, the potential safety hazard brought by the excessive vibration of the stator iron core and the winding end part are prevented, and the long-term stable operation of a unit is ensured.

The invention relates to an apparatus and method of improving spacecraft attitude stability, belonging to the spacecraft attitude dynamics and vibration inhibition field. The framework bearing of each SGCMG is provided with a vibration isolation element; each vibration isolation element includes a plurality of metal springs respectively in connection with the internal wall and the external wall of the vibration isolation element through spherical hinges. The internal wall of the vibration isolation element sleeves the framework bearing of an SGCMG so as to be in connection with the framework bearing of the SGCMG; the external wall of the vibration isolation element is directly in fixed connection with a satellite body. The vibration isolation elements can effectively solve the vibration problem of an SGCMG, and possess a decoupling characteristic so as to effectively and rapidly realize the parameter design of vibration isolation elements; in addition, the vibration isolation elements can greatly improve satellite attitude stability.

The invention relates to a maximum power point detection tracking method and circuit, in particular to a maximum power point detection tracking method and circuit of a power generating device. The maximum power point detection tracking method of the power generating device mainly comprises the following steps of: within a determined energy absorbing conversion period, taking 0.1%-1% of time of the energy absorbing conversion period to scan an output current and an output voltage of the power generating device; detecting a peak value of a power value; and locking a scanning current value corresponding to the detected maximum power point in a memorized way. The maximum power point detection tracking circuit of the power generating device, provided by the invention, comprises a power scanning circuit, a peak value detecting unit circuit and a tracking unit circuit. By using the maximum power point detection tracking method and circuit of the power generating device, provided by the invention, the maximum power points of the various power generating devices can be detected and tracked; and the method and circuit have the advantages of simple structure, short locking time, no maximum power point vibration problem and the like.

The invention discloses a mechanical arm anti-collision system and method and a storage medium. The method comprises the steps that speed and accelerated speed information of the tail end of a mechanical arm is obtained through measurement of an MEMS sensor installed at the tail end of the mechanical arm, the measured speed and accelerated speed information is compared with standard speed and accelerated speed information, when a comparison result shows that the deviation exceeds a set threshold value, the problem that vibration is caused by collision or other reasons is determined by analyzing change trends of the speed and the accelerated speed which are measured by the MEMS sensor in the set time period, and protection control is conducted on the mechanical arm when collision occurs. According to the technical scheme, damage to the mechanical arm and obstacles caused by collision can be avoided to the maximum limit, and the cost is low.

The invention provides an electrical-acoustic converting device and a suspending mechanism thereof. The suspending mechanism of the electrical-acoustic converting device is connected between a voice coil and a basin stand of the electrical-acoustic converting device. The suspending mechanism comprises a first structural part and a second structural part, wherein the first structural part is an elastic conducting part, the elastic conducting part is provided with a conducting internally-connected structure and a conducting externally-connected structure, the conducting internally-connected structure is connected to a free end of the voice coil and is electrically connected with a wire of the voice coil, and the conducting externally-connected structure is connected with the basin stand; the second structural part and the first structural part are in symmetry about the center of the voice coil, and the second structural part is connected between the voice coil and the basin stand. According to the electrical-acoustic converting device and the suspending mechanism thereof, the rolling vibration problem of the electrical-acoustic converting device can be effectively inhibited or even totally solved.

The invention belongs to the field of turbochargers for internal combustion engines, in particular to a rotor supporting mechanism of a rolling bearing turbocharger. It includes a bearing sleeve and two springs, two thrust sleeves and two bearings in the bearing sleeve. The two springs are symmetrically arranged in the bearing sleeve and connected to each other. Put the spring into the thrust sleeve and apply pre-tightening force. Two bearings are respectively arranged on the end face of the thrust sleeve. Both bearings are angular contact rolling bearings. The advantage of the present invention is that ceramic rolling bearings are used instead of ordinary floating bearings, which improves the mechanical efficiency and transient response capability of the turbocharger, solves the vibration problem of the rolling bearing turbocharger, and improves the steady-state performance and performance of the turbocharger. The service life of the rolling bearing is improved, the support rigidity of the rolling bearing is improved, the limit speed of the rolling bearing is increased, the requirement of high-speed operation of the turbocharger is met, the lubrication problem of the turbocharger is solved, the reliability of the rolling bearing supercharger is improved, and the balanced transmission The force system meets the requirements for the normal operation of the rolling bearing turbocharger.

The invention relates to a method for calculating the inherent frequency of a Euler-Bernoulli beam through an improved differential transformation method. The method comprises the steps that the improved differential transformation method is deduced on the basis of a differential transformation method; a corresponding oscillatory differential equation is built, the improved differential transformation method is used for solving the free vibration problem of the homogeneous Euler-Bernoulli beam with two freely-supported ends, a control differential equation is converted into an algebraic equation, and boundary conditions are changed to an algebraic frequency equation convenient to calculate; corresponding algebraic operation is carried out to obtain the inherent frequency and the modal shape of any order of the differential equation. According to the method for calculating the inherent frequency of the Euler-Bernoulli beam through the improved differential transformation method, the improved differential transformation method is used for solving the free vibration problem of the homogeneous Euler-Bernoulli beam, an approximate solution of a nonlinear problem is obtained in the mode that iteration is carried out to converge the series, closed-form solutions such as the four-order inherent frequency and the modal shape are obtained, the solution of a Taylor expansion power series can be converged at a larger time interval, and the calculation process is rapider and more accurate.

The invention discloses a semi-active dynamic vibration absorber for magneto-rheological elastomers and a selection and installation method. According to the semi-active dynamic vibration absorber andthe selection and installation method, multiple layers of cross-shaped cross beams arranged in parallel are fixed to the positions below a bottom frame base located at the bottom of a railway vehiclein a suspended mode through four vertical magnetic conductive rods arranged vertically and penetrating through the four end parts of cross-shaped beam arms; multiple layers of stacked structures which are spaced from each other are formed between multiple layers of grooving vibrators and the cross-shaped cross beams; vertical mounting through holes are formed in the centers of the cross-shaped cross beams; the annular magneto-rheological elastomers are arranged between the mounting through holes and a connecting shaft of the multiple layers of grooving vibrators; the multiple layers of grooving vibrators can vibrate up and down relative to the bottom frame base in the axial direction of the mounting through holes; winding grooves are formed in the beam arms of the cross-shaped cross beams; and excitation coils are wound in the winding grooves. The semi-active dynamic vibration absorber has the advantages that the vibration absorption effect is good, the energy consumption is small, the structure is simple and compact, the installation is easy, the safety and the reliability are high, the utilization of the residual space under the railway vehicle is reasonable, and vertical wide-frequency vibration reduction can be carried out on a railway vehicle body which suffers form an abnormal vibration problem due to the fact that a railway is unsmooth.

The invention discloses a topological structure and a control method of an improved SEN transformer. The topological structure of the improved SEN transformer consists of an SEN transformer and a unified power flow controller connected in series, wherein the SEN transformer is connected with an electric transmission line in series; a parallel connection variator VSC1 of the unified power flow controller is connected with the equivalent head end of a power distribution network transmission system in parallel; a parallel connection variator VSC2 of the unified power flow controller is connected with the equivalent tail end of the power distribution network transmission system in parallel. 360-degree discrete adjustable series connection voltage is realized through controlling a common on-load tap changer by the SEN transformer; 360-degree continuous adjustable series connection voltage is realized through controlling an electronic power switch by the unified power flow controller. The topological structure and the control method of the improved SEN transformer have the advantages that the voltage is continuously adjustable, the compensation accuracy is high, the switching vibration problem is avoided, and the like, and can be used for regulating and controlling the electric transmission line power flow distribution.

The invention discloses a crane and a boom thereof. The boom comprises a basic boom; at least one level of a telescopic boom group sleeved in the basic arm in sequence, wherein the telescopic group includes a first telescopic boom and a second telescopic boom sleeved in the first telescopic boom, and the end of the first telescopic boom in the telescopic boom group is provided with a first locking pin hole; at least one rope unwinding mechanism, wherein the rope unwinding mechanism is arranged between the second telescopic boom and the first telescopic boom of all the telescopic groups; and a telescopic cylinder arranged in the boom in an axial direction, wherein the piston rod end of the telescopic cylinder is fixedly connected to the end of the basic boom, and a locking pin cooperated with the first locking pin hole is arranged on the outer wall of the telescopic cylinder. According to the present invention, only one boom is driven out by the rope unwinding mechanism, thus greatly reducing the impact of rope elasticity to the telescopic mechanism, and effectively solving the boom stretching vibration problem due to a plurality of groups of rope unwinding mechanisms.

The invention discloses a hermetic sealing and gas-liquid separation and recovery device for an immersed photoetching machine, which is installed between a projection objective group of the immersed photoetching machine and a silicon wafer, and comprises a seal and injected liquid recovery device, a gas-liquid separation sheet group and a liquid recovery sheet group, wherein the seal and injected liquid recovery device is composed of an immersion unit front end cover and an immersion unit rear end cover. The hermetic seal and gas-liquid separation and recovery device is used for completing the functions of seal and injected liquid recovery in a slit flow field of the immersed photoetching system, so as to achieve continuous and stable updating of the slit flow field. A hermetic sealing structure is used at the edge of the slit flow field to prevent liquid leakage, a gas-liquid separation and recovery structure is adopted to achieve separation and respective recovery of gas and liquid, and generation of gas-liquid two-phase flow is avoided, so that the pipeline vibration problem caused by simultaneous recovery of gas-liquid two-phase flow is avoided. No matter which direction the silicon wafer moves to, the gas-liquid separation and recovery structure can dynamically adjust the height of the liquid level in the device.

The invention belongs to the technical field of flow induced vibration and relates to a device for pipeline vibration testing. The device comprises a driving mechanism, vibration isolation sections attwo ends, a U-shaped bent pipe section, a test piece, a visual pipe section, a pipeline supporting structure and a pressure measuring system, wherein the vibration isolation sections are arranged attwo ends of the device, the visual pipe section, the test piece and the U-shaped bent pipe section are sequentially connected between the two vibration isolation sections, the pressure test system isinstalled before and behind the test piece, the driving mechanism is arranged at one side of the U-shaped bent pipe section and is connected with the vibration isolation section, and the pipeline supporting structure is used for supporting the whole device. The device can simulate a vibration problem caused by the change of a flow field inside a pipeline and verify the numerical calculation modelof pipeline vibration. With a simple method adopted, the state of the pipeline can be accurately evaluated, and a pipeline vibration solution can be verified.

The invention discloses a cable-stayed flexible photovoltaic bracket unit and a photovoltaic bracket. The bracket unit comprises two oppositely arranged upright posts, a stabilization cable and a plurality of main diagonal cables are arranged between the two upright posts, and the two ends of the stabilization cable are respectively connected to the lower parts of the upright posts on the corresponding ends; all main diagonal cables are divided into two groups, each group at least comprises one main diagonal cable, the upper ends of all main diagonal cables of each group are connected to the upper parts of the upright posts on the corresponding ends, the lower ends of the two groups of main diagonal cables are connected with a cross beam, and connection points are uniformly arranged alongthe length direction of the cross beam, and the cross beam is horizontally arranged; and a plurality of slings are equidistantly arranged between the cross beam and the stabilization cable along the vertical direction, the upper ends of all slings are connected with the cross beam, and the lower ends of all slings are connected with the stabilization cable. By adoption of an optimized self-balancing prestressed cable system, the vertical stiffness of the structure is improved, and the vibration problem under the wind load is solved, thereby significantly improving the spanning capability of the photovoltaic bracket, further reducing the floor space, and having relatively high adaptability on complex terrain areas.

The invention provides a valve support and an air conditioner comprising the valve support. According to the valve support, the valve support comprises a valve support body, a valve installing opening is arranged on the valve support body, the valve support further comprises a pipeline piece fixing portion fixedly connected with the valve support body, and a clamping port matched with a pipeline piece is arranged on the pipeline piece fixing portion. According to the valve support and the air conditioner comprising the valve support, due to the fact that the pipeline piece fixing portion is arranged on the valve support body, the pipeline piece is effectively fixed through the clamping opening on the pipeline piece fixing portion, the vibration problem caused by suspension or unstable fixation of the pipeline piece is avoided, and the performance and the reliability of the air conditioner are improved.

The invention aims to provide a vibration analysis method of a passive constrained damping rotating body structure. The boundary condition information of the passive constrained damping rotating body structure is extracted; the passive constrained damping rotating body structure consists of two parts including a soft structure and a hard structure, wherein the soft structure is a middle damping layer, and the hard structure consists of an inner substrate, an outer substrate and a constrained layer; the soft structure and the hard structure are connected in a displacement way by an interlayer continuity condition; according to a first order shear deformation theory, relationship between middle surface strain and curvature and the relationship between the middle surface strain and displacement in the soft structure and the hard structure are independently determined, the total energy of the passive constrained damping rotating body structure is determined, a solver is established according to a Rayleigh-Ritz principle for solving, and the inherent frequency and the loss factor of the structure are output. The method can be used for solving a vibration problem and a damping analysis problem of the passive constrained damping rotating body structure under various complex boundary conditions including various classical boundary conditions, general elastic boundary conditions and non-uniform constraint boundary conditions.

The invention provides a vehicle-mounted data unit (10), a method, engineering machinery and a system of cantilever crane vibration monitoring. The vehicle-mounted data unit (10) comprises a vibration detector (1), a controller (2) and a storage device (3), wherein the vibration detector (1) is used for detecting cantilever crane vibration and outputting vibration signals characterizing the cantilever crane vibration in real time, the controller (2) is used for receiving the vibration signals output by the vibration detector (1) to generate vibration data and to compare vibration intensity obtained according to the vibration signals with a preset vibration triggering threshold valve, when the vibration intensity is larger than the vibration triggering threshold value, the controller (2) transmits the vibration data to the storage device (3), and the storage device (3) is used for storing the vibration data received. Thus, when a vibration problem happens, even through a technician is not on site, first-hand on-site vibration data can be recorded, and the accident that timely data recording can not achieved due to the transfer of a pump truck can not happen. Moreover, the vibration data is stored only when the vibration is too strong, the storage times of the storage device are reduced, and the service life of hardware is prolonged.