CN106678274A - Shafting longitudinal vibration absorber based on piezoelectric stack - Google Patents
Shafting longitudinal vibration absorber based on piezoelectric stack Download PDFInfo
- Publication number
- CN106678274A CN106678274A CN201710124592.1A CN201710124592A CN106678274A CN 106678274 A CN106678274 A CN 106678274A CN 201710124592 A CN201710124592 A CN 201710124592A CN 106678274 A CN106678274 A CN 106678274A
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- Prior art keywords
- piezoelectric pile
- base
- piezoelectric stack
- piezoelectric
- shafting
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/22—Compensation of inertia forces
- F16F15/26—Compensation of inertia forces of crankshaft systems using solid masses, other than the ordinary pistons, moving with the system, i.e. masses connected through a kinematic mechanism or gear system
- F16F15/264—Rotating balancer shafts
- F16F15/265—Arrangement of two or more balancer shafts
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Aviation & Aerospace Engineering (AREA)
- Mechanical Engineering (AREA)
- Apparatuses For Generation Of Mechanical Vibrations (AREA)
Abstract
The invention provides a shafting longitudinal vibration absorber based on a piezoelectric stack. The shafting longitudinal vibration absorber comprises an upper base, a lower base and driving actuators arranged between the upper base and the lower base; each driving actuator comprises a piezoelectric stack shell, a lower ball head-taper hole force transferring device arranged at the inner bottom of the piezoelectric stack shell, the piezoelectric stack connected with the end of the lower ball head-taper hole force transferring device, an upper ball head-taper hole force transferring device connected with the end of the piezoelectric stack, output shafts connected with the end of the upper ball head-taper hole force transferring device, precompression springs arranged between the output shafts and the inner top ends of the piezoelectric stack shell, and inertia mass blocks; the ends of the output shafts extend out of the piezoelectric stack shell, and the inertia mass blocks are installed at the ends of the output shafts; and the lower end of the piezoelectric stack shell and the upper base are connected; and one ends of the output shafts stretch into drilled holes formed in the lower base. The shafting longitudinal vibration absorber is convenient to install, little in energy consumption, large in output force, highly integrated and small in occupied space.
Description
Technical field
The present invention relates to a kind of device of antivibration area, more particularly to a kind of shafting longitudinal vibration based on piezoelectric pile
Bump leveller.
Background technology
Propeller is the main propulsion plant of surface vessel and submarine.Submarine is during traveling inevitably in stern
Uneven Wake Field is formed, propeller rotates in uneven Wake Field can produce pulsation thrust, by Propulsion Systems, thrust
Bearing and its pedestal are delivered to submarine, cause hull to produce vibration, and then produce acoustic radiation.
Transfer law and shafting vibration of the propeller exciting force in Propulsion Systems, in the vibration active control system of shafting
In be an important ring, be the key for causing submarine shafting low-frequency vibration.The exciting force of propeller mainly has longitudinally, laterally and turns round
Turn pulsating force, wherein longitudinal pumping power is again major part.Meanwhile, the extensional vibration tool of the ship housing that longitudinal pulsating force is caused
The radiation characteristic of sound monopole is have radiation efficiency very high, in addition because longitudinal pulsating force of propeller passes through shafting base
Seat passes to naval vessels housing, causes hull vibration and then outside radiated noise.So, the shafting longitudinal vibration of naval vessels should cause
Pay much attention to.
From the general principle of vibration control, reducing naval vessel shafting vibration mainly has three approach.One is to reduce ship
Whole vibration response, two is the exciting force input for reducing propeller using big tiltedly side oar, next to that control vibration is in shafting
Transmission.The first two scheme is because the limitation of technical elements, it is difficult to have further improve again, so enterprising in vibration transfer path
The technological approaches of row control most Practical meaning.
Piezoelectric actuator is operated using inverse piezoelectric effect principle, i.e., apply alternating electric field, piezoelectricity on piezo-electric crystal
Crystal will produce the mechanical strain of alternation electricity in a direction.It is increase output displacement, generally uses stacked piezoelectric actuating
Device.Piezoelectric pile actuator machinery positioning is high, and energy consumption is low, and response is fast, can directly convert electrical energy into mechanical energy.
Found by existing retrieval, mainly use active bump leveller, damper to indulge marine shafting at present
Shake control.Luo Qiang (Luo Qiang, the hydraulic shock-absorbing device for reducing shafting subsystem extensional vibration is studied, Shanghai Marine Equipment Research Institute,
2014.3) damping mechanism, longitudinal Static stiffness characteristic, the equivalent power parameter identification of hydraulic shock-absorbing device are analyzed, is being established
After naval vessel shafting subsystem model, influence of the analysis sub-system major parameter to hydraulic shock-absorbing device effectiveness in vibration suppression.Yang Zhirong
(Yang Zhirong, naval vessels shafting longitudinal vibration characteristics and the semi- active control technical research based on magnetic rheology elastic body, Shanghai Communications University,
2014.7) propose and design a kind of magnetic rheology elastic body dynamic vibration absorber being installed in parallel on Propulsion Systems, by magnetic
The experimental study of magnetorheological elastomer dynamic vibration absorber, the shock attenuation result to single magnetic rheology elastic body dynamic vibration absorber is tested
Card, is that practical application of the magnetic rheology elastic body dynamic vibration absorber on naval vessels is laid a good foundation.Open Jiangxi ripple (a Jiangxi ripple, ship master
Propulsion Systems extensional vibration Active Control Method is studied, the Central China University of Science and Technology, 2012.1) vibration that analyzes main Propulsion Systems is special
Property and the hull sound vibration characteristic that is caused by vibration, and dynamic vibration absorber is arranged between thrust bearing and its pedestal, by comparing
The radiated sound field of hull before and after installing, forecast dynamic vibration absorber is to promoting mainly the hull radiated noise caused into shafting longitudinal vibration
Control effect.
It is existing《Electromagnetic active control device for longitudinal vibration of marine shafting》(the patent No.:The A of CN 102072276) by electricity
Magnetic-type inertia bump leveller is fixed in shafting, and bump leveller is arranged at jackshaft and receives the control signal after amplifying to produce accordingly
Longitudinal direction be used as power and act on jackshaft, realize the extensional vibration control of shafting, but Electromagnet absorber installs inconvenience, power output
It is limited, and Electromagnet absorber reliable long-term working is not high.《Combined magnetic magnetorheological elastomer marine shafting longitudinal vibration intelligence absorbing》
(the patent No.:The A of CN 102878237) multiple magnetic rheology elastic bodies are in parallel, it is fixed in shafting by upper lower disc pedestal, and
Change the mass ratio of bump leveller by adjusting elastomer quantity.Magnetic rheology elastic body in the bump leveller is pursuing mechanical performance
It is conflicting during with magnetic rheology effect, often result in elastomer tunable band not wide, it is impossible to play magnetic rheology elastic body very well
Variation rigidity effect.
The content of the invention
The invention aims to provide a kind of easy for installation, less energy consumption, High power output, Highgrade integration, sky is occupied
Between the low shafting longitudinal vibration bump leveller based on piezoelectric pile.
The object of the present invention is achieved like this：Including top base, bottom base and it is arranged between top base and bottom base
Active executing agency, the active executing agency includes piezoelectric pile shell, is arranged on the lower bulb-cone at bottom in piezoelectric pile shell
Upper bulb-the cone of the piezoelectric pile and the connection of piezoelectric pile end of hole load transfer device and lower bulb-taper hole load transfer device end connection
The take-off lever of hole load transfer device and upper bulb-taper hole load transfer device end connection, it is arranged in take-off lever and piezoelectric pile shell and pushes up
Pre-compressed spring, inertial mass between end, the end of the take-off lever extend out to outside piezoelectric pile shell and inertial mass is pacified
Mounted in the end of take-off lever, the end that the lower end of the piezoelectric pile shell is connected take-off lever with top base stretches to and set on bottom base
In the drilling put.
Present invention additionally comprises such some architectural features：
1. active executing agency described in has four, and four active executing agencies be symmetricly set on top base and bottom base it
Between.
2. top base, bottom base are constituted by two semicircular rings and for connecting the connector of two semicircular rings, and on
Four internal thread holes are provided with pedestal, pressure is realized in the lower end of piezoelectric pile shell by bolt with the cooperation of corresponding internal thread hole
Electricity pushes away the connection of shell and top base, and the number of the drilling set on bottom base is 4, and the inner surface of each drilling scribbles lubrication
Oil.
Compared with prior art, the beneficial effects of the invention are as follows：A kind of shafting based on piezoelectric pile of the invention is longitudinally inhaled
Shake device, compared to traditional piezoelectric pile actuator, can guarantee that piezoelectric pile is not contacted directly with controlled object, is not subject to static load, resists
Impact capacity is stronger.The present invention does not exist electromagnetic interference, and piezoelectric pile actuator is nearly free from heat, mechanical energy conversion effect in addition
Rate is high, easy for installation, it is not necessary to change original shafting structure.The present invention after piezoelectric pile is passed through voltage, using inverse piezoelectric effect,
Mass motion is driven, bigger being used as power can be exported.
Brief description of the drawings
Fig. 1 is structural representation of the invention；
Fig. 2 is the structural representation of active executing agency of the present invention；
Fig. 3 is the theory diagram of active executing agency of the present invention；
Fig. 4 is the control flow theory diagram of one embodiment of the present invention；
Wherein：2- inertial mass, 3- top bases, 4- bottom bases, 5- take-off levers, 6- pre-compressed springs, 7- piezoelectric piles, 8- balls
Head-taper hole load transfer device, 9- piezoelectric pile shells.
Specific embodiment
The present invention is described in further detail with specific embodiment below in conjunction with the accompanying drawings.
As shown in figure 1, a kind of shafting longitudinal direction bump leveller based on piezoelectric pile of the present invention, including top base 3 and bottom base 4,
Active executing agency, top base 3 is made up of 2 semi-discs, and bottom base 4 is also made up of two semi-discs, and semi-disc passes through bolt
It is fastenedly connected；Top base, bottom base and active executing agency form a whole.
The structural representation of active executing agency of the present invention is illustrated in figure 2, described active executing agency passes through wire
It is connected with external voltage amplifier；Active executing agency is by shell 9, piezoelectric pile 7, bulb-taper hole load transfer device 8, pre-compressed spring 6
Constituted with take-off lever 5.Power take-off lever and executing agency's tail end are all connected by bulb-taper hole load transfer device with piezoelectric pile, in order to avoid
Error during the incoming or assembling of power take-off lever bending load causes Moment in piezoelectric pile, so as to ensure that piezoelectric pile is not received
Any bending load.Described active actuator stem has external screw thread, take-off lever and inertia matter with mass linkage section car
Gauge block is bolted connection, it is ensured that in the absence of relative slip.Described top base car has 4 internal threads, is performed with active
The number of mechanism is corresponding, and each internal thread has internal thread, piezoelectric pile and top base in 45 ° of circumferential installations, piezoelectric pile bottom car
It is bolted connection, it is ensured that be brought into close contact.Piezoelectric pile is by several pieces (according to actual installation space and requirement selection number of exerting oneself
Amount) piezoelectric ceramic piece by tack coat stack form, there is interdigital electrode centre, and circuit is parallel, on mechanics series connection.
Single layer piezoelectric piece produces displacement in the electric field, by multiple-layer stacked so that output displacement increases.Because piezoelectric pile can not bear compared with
Big tension, it is therefore desirable to pre-compressed spring 6 is loaded onto at the top of piezoelectric pile, preloading spring one end is connected with power take-off lever, precompressed
The other end of spring 6 is then connected on power take-off lever 5, eliminates the axial gap between each component with this, it is ensured that piezoelectric pile is located all the time
In pressured state.Overall package is in housing 9.
Described bottom base car has 4 drillings, and the number with active executing agency is corresponding, and each drilling is in 45 ° of circumferences
Install, in the insertion smooth drilling of bottom base of active actuator stem end, further, lubricating oil is scribbled in drilling, with
Reduce friction.
The non-cutting thread in end of the take-off lever of described executing agency, further, it is ensured that the end of take-off lever will not be with
Foot of hole is contacted.Described upper bottom base is fixed by bolt with shafting.Take-off lever 5 and inertial mass 2 are tight by bolt
It is solidly connected, it is ensured that in the absence of relative displacement.
As shown in figure 3, the rigidity of piezoelectric pile 7 can be reduced to kp, being used as power for generation is Fa, inertial mass is m, matter
The displacement of gauge block is x1(t), therefore the inertia force of output is FiT (), specific expression formula is as follows：
It is instantiation of the invention with reference to accompanying drawing 4, tach signal when jackshaft is rotated is measured with speed probe, makees
It is the reference signal of controller, acceleration transducer is placed in obtain vibration acceleration on thrust bearing, used as controller error
Signal, error signal, as the final input quantity of controller after low pass filter and A/D conversions, is controlled by charge amplifier
Device after being changed through D/A, then outputs voltage signal to piezoelectric pile work according to certain control algolithm, output control signal by power amplifier
Dynamic device, piezoelectric pile, along longitudinal extension, changes bump leveller intrinsic frequency in real time in the presence of electric field, so as to play shaft vibration
Control with absorb.
To sum up, present invention aim at a kind of shafting longitudinal vibration bump leveller based on piezoelectric pile is provided, bump leveller is belonged to
Field.It is made up of active executing agency, top base, bottom base；Active executing agency include shell, bulb-taper hole load transfer device,
Power take-off lever, piezoelectric pile, pre-compressed spring and mass composition；Top base is connected by upper and lower semicircle disc type shafting Hough；Bottom base
It is connected by upper and lower semicircle disc type shafting Hough；Top base bottom car has 4 screwed holes；Bottom base disc surfaces car have 4 it is smooth
Drilling；Further, 4 screwed holes of top base are in 45 ° of circumferential installations；Further, 4 drillings of bottom base are in 45 ° of weeks
To installation；Take-off lever end insertion 4 drillings of bottom base of piezoelectric pile；Lubricating oil is scribbled in the boring surface of bottom base.Work
When, piezoelectric pile is passed through voltage and produces inverse piezoelectric effect, drives mass to move by power take-off lever, so as to produce inertia force, enters
One step ground, piezoelectric pile bottom is fastened by bolts with top base and is rigidly connected, the reaction force acts of generation on top base from
And suppress shafting longitudinal vibration.The present invention is easy for installation, and simple structure, reliability are high, applicable band is wide, can be with shafting vibration
The frequency of the change adjustment bump leveller itself of frequency, so as to reach the requirement of shaft vibration and noise reducing.Particular for Modern Ships,
" Sound stealth " of submarine shafting requires, can play its and be worth.
Claims (3)
1. a kind of shafting longitudinal vibration bump leveller based on piezoelectric pile, it is characterised in that：Including top base, bottom base and it is arranged on
Active executing agency between top base and bottom base, the active executing agency includes piezoelectric pile shell, is arranged on piezoelectric pile
The piezoelectric pile and piezoelectric pile of the lower bulb-taper hole load transfer device and lower bulb at bottom-taper hole load transfer device end connection in shell
Upper bulb-taper hole the load transfer device of end connection and the take-off lever of upper bulb-taper hole load transfer device end connection, be arranged on it is defeated
Pre-compressed spring, inertial mass in rod and piezoelectric pile shell between top, the end of the take-off lever extend out to piezoelectric pile
Shell is outer and inertial mass is installed in the end of take-off lever, and the lower end of the piezoelectric pile shell is connected take-off lever with top base
End is stretched in the drilling set on bottom base.
2. a kind of shafting longitudinal vibration bump leveller based on piezoelectric pile according to claim 1, it is characterised in that：The master
Dynamic executing agency has four, and four active executing agencies are symmetricly set between top base and bottom base.
3. a kind of shafting longitudinal vibration bump leveller based on piezoelectric pile according to claim 2, it is characterised in that：Upper base
Seat, bottom base are constituted by two semicircular rings and for connecting the connector of two semicircular rings, and four are provided with top base
Individual internal thread hole, the lower end of piezoelectric pile shell piezoelectric push shell and upper base are realized by bolt and the cooperation of corresponding internal thread hole
The connection of seat, the number of the drilling set on bottom base is 4, and the inner surface of each drilling scribbles lubricating oil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710124592.1A CN106678274A (en) | 2017-03-03 | 2017-03-03 | Shafting longitudinal vibration absorber based on piezoelectric stack |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710124592.1A CN106678274A (en) | 2017-03-03 | 2017-03-03 | Shafting longitudinal vibration absorber based on piezoelectric stack |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106678274A true CN106678274A (en) | 2017-05-17 |
Family
ID=58862528
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710124592.1A Pending CN106678274A (en) | 2017-03-03 | 2017-03-03 | Shafting longitudinal vibration absorber based on piezoelectric stack |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107387652A (en) * | 2017-06-05 | 2017-11-24 | 上海交通大学 | A kind of Propulsion Systems distribution active damper |
| CN108119603A (en) * | 2017-12-07 | 2018-06-05 | 南京航空航天大学 | A kind of vibration damping loop device based on piezo-electric stack |
| CN109780108A (en) * | 2019-02-14 | 2019-05-21 | 沈阳工业大学 | Driveline damping damping unit based on giant magnetostrictive material |
| CN110440087A (en) * | 2019-08-15 | 2019-11-12 | 武汉理工大学 | It is a kind of based on piezoelectric stack driving pipeline actively subtract isolation mounting and control system |
| CN114183497A (en) * | 2021-12-17 | 2022-03-15 | 中国船舶重工集团公司第七0九研究所 | Triaxial initiative shock absorber and system based on piezoelectric effect |
| CN117469339A (en) * | 2023-12-28 | 2024-01-30 | 中闽(福清)风电有限公司 | Variable-rigidity variable-damping magnetorheological vibration absorber control method applied to propulsion shaft system |
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| JP2010281407A (en) * | 2009-06-05 | 2010-12-16 | Shimizu Corp | Damping mechanism and installation method therefor |
| CN105864353A (en) * | 2016-06-12 | 2016-08-17 | 哈尔滨工程大学 | Inertia-type hybrid vibration isolator based on piezoelectric stack |
| CN105972370A (en) * | 2016-05-27 | 2016-09-28 | 哈尔滨工程大学 | Novel variable-rigidity semi-active pipeline vibration absorber |
| CN106439301A (en) * | 2016-10-08 | 2017-02-22 | 中国船舶重工集团公司第七〇九研究所 | Pipeline system three-way active/passive vibration absorbing ring |
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2017
- 2017-03-03 CN CN201710124592.1A patent/CN106678274A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2010281407A (en) * | 2009-06-05 | 2010-12-16 | Shimizu Corp | Damping mechanism and installation method therefor |
| CN105972370A (en) * | 2016-05-27 | 2016-09-28 | 哈尔滨工程大学 | Novel variable-rigidity semi-active pipeline vibration absorber |
| CN105864353A (en) * | 2016-06-12 | 2016-08-17 | 哈尔滨工程大学 | Inertia-type hybrid vibration isolator based on piezoelectric stack |
| CN106439301A (en) * | 2016-10-08 | 2017-02-22 | 中国船舶重工集团公司第七〇九研究所 | Pipeline system three-way active/passive vibration absorbing ring |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107387652A (en) * | 2017-06-05 | 2017-11-24 | 上海交通大学 | A kind of Propulsion Systems distribution active damper |
| CN108119603A (en) * | 2017-12-07 | 2018-06-05 | 南京航空航天大学 | A kind of vibration damping loop device based on piezo-electric stack |
| CN109780108A (en) * | 2019-02-14 | 2019-05-21 | 沈阳工业大学 | Driveline damping damping unit based on giant magnetostrictive material |
| CN110440087A (en) * | 2019-08-15 | 2019-11-12 | 武汉理工大学 | It is a kind of based on piezoelectric stack driving pipeline actively subtract isolation mounting and control system |
| CN114183497A (en) * | 2021-12-17 | 2022-03-15 | 中国船舶重工集团公司第七0九研究所 | Triaxial initiative shock absorber and system based on piezoelectric effect |
| CN114183497B (en) * | 2021-12-17 | 2024-02-27 | 中国船舶重工集团公司第七0九研究所 | Triaxial active vibration damper based on piezoelectric effect and system thereof |
| CN117469339A (en) * | 2023-12-28 | 2024-01-30 | 中闽(福清)风电有限公司 | Variable-rigidity variable-damping magnetorheological vibration absorber control method applied to propulsion shaft system |
| CN117469339B (en) * | 2023-12-28 | 2024-03-08 | 中闽(福清)风电有限公司 | Variable-rigidity variable-damping magnetorheological vibration absorber control method applied to propulsion shaft system |
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Application publication date: 20170517 |