CN201836154U - High-frequency electrohydraulic fluttering generator - Google Patents
High-frequency electrohydraulic fluttering generator Download PDFInfo
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- CN201836154U CN201836154U CN2010202216949U CN201020221694U CN201836154U CN 201836154 U CN201836154 U CN 201836154U CN 2010202216949 U CN2010202216949 U CN 2010202216949U CN 201020221694 U CN201020221694 U CN 201020221694U CN 201836154 U CN201836154 U CN 201836154U
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Abstract
The utility model discloses a high-frequency electrohydraulic fluttering generator, which comprises an alternating current valve and a fluttering cylinder. The fluttering cylinder comprises a cylinder body. The side wall of the cylinder body is provided with an oil inlet/outlet hole. A fixed end cover is arranged at one end of the cylinder body, while an elastic end cover connected with the load is arranged at the other end of the cylinder. The alternating current valve comprises a valve body, a valve sleeve, a valve core, a rotary power mechanism for driving the valve core to rotate and a sliding power mechanism for driving the valve core to slide. The valve body is provided with an oil inlet port, an oil outlet port and an oil returning port. The oil outlet port communicates with the oil inlet/outlet hole. The oil inlet port and the oil returning port communicate with hydraulic oil sources. A valve cavity for the valve core to insert in is arranged in the valve body. A valve sleeve is sleeved outside the valve core.Four shoulders are arranged on the valve core and groove ports on the two shoulders are in mutual dislocation. The valve sleeve is provided with four groups of windows along an axial direction and the space between the adjacent windows is equal to the space between the two shoulders at the inner side. The high-frequency electrohydraulic fluttering generator is suitable for occasions with great exciting forces and high-frequency micro-amplitude occur and has small volume.
Description
Technical field
The utility model relates to a kind of high-frequency electrohydraulic fluttering generator.
Background technique
Mainly contain three types vibration equipment at present, performance characteristics is as follows: 1. mechanical type mainly is divided into centrifugal and direct acting type two classes.The frequency range of centrifugal mechanical shake unit is generally 5～100Hz, and load is 50～10000N; The frequency range of direct acting type mechanical vibrator is 1～200Hz, can obtain very big thrust and bigger amplitude.This class shake unit is simple in structure, cost is low, but upper limiting frequency is lower, is widely used in various low-frequency vibration occasions.2. electromagnetic type, can produce complicated vibrational waveform, have advantages such as waveform distortion is less, operating frequency range is big, owing to be subjected to intrinsic magnetically saturated restriction, be difficult for to obtain big excitation force, in addition, the device structure complexity, vibration displacement is limited and need radiator cooler, therefore, be mainly used in vibration mechine.The frequency range of small-sized electromagnetic type vibrating table is 0～10kHz, and large-scale electromagnetic type vibrating table frequency range is 0～2kHz, is mainly used in fields such as Aeronautics and Astronautics and national defence.3. hydraulic type is widely used in pile driving by vibration, vibration forging, vibration molding, oscillatory shear, vibrating compaction, vibrating transportation, vibrating sieve, farm machinery and vibration mechine etc.In the above-mentioned 3 class vibration equipment, hydraulic type thrust maximum.
In the engineering for big excitation force, high frequency a little (amplitude from 2 μ m to 100 μ m, frequency from the number Hz to the number kHz) and the demand of small volume vibrator more and more urgent; But the excitation force that existing electric and magnetic oscillation equipment is exported when dither is little can not to satisfy requirements at the higher level in the engineering.
Summary of the invention
In order to overcome the deficiency that existing vibration equipment can not be applicable to needs big excitation force, high frequency occasion a little simultaneously, the utility model provides a kind of can be applicable to big excitation force, the high frequency little high-frequency electrohydraulic fluttering generator of occasion, volume a little.
The technological scheme that its technical problem that solves the utility model adopts is:
A kind of high-frequency electrohydraulic fluttering generator, comprise and exchange valve and flutter cylinder, described flutter cylinder comprises cylinder body, described cylinder side wall has a turnover oilhole, described cylinder body one end installs and fixes end cap, the other end of cylinder body is installed the elasticity end cap that is connected with load, and described interchange valve comprises valve body, valve pocket, spool and drives the rotational power mechanism of valve core rotation and drive the sliding power mechanism that spool slides; Described valve body is provided with a filler opening, an oil outlet and a return opening, and described oil outlet is communicated with described turnover oilhole, and described filler opening and return opening are communicated with hydraulic oil source; Have the valve pocket that inserts for spool in the described valve body, suit valve pocket outside the described spool has 4 shoulders on the spool, and wherein two shoulders in the outside are the supporting shoulder, and inboard two shoulders are at circumferential even respectively processing Z
1Individual notch, Z
1Be even number, the notch mutual dislocation on two shoulders; Valve pocket is opened 4 group windows vertically, and the spacing between two shoulders of spacing between the adjacent window apertures and inboard equates that middle 1 group window is along circumferentially evenly offering Z
2Individual T type window, Z
2Be even number, Z
2=Z
1+ 2, Z is circumferentially evenly offered on 3 groups of edges, the outside
2Individual rectangular window, from the radial cross section direction, the position consistency of each group window.
As the another kind of scheme of preferred flutter cylinder: described flutter cylinder also comprises movable end cover and adjustable lever, the sidewall of described movable end cover and described cylinder body is tightly connected, described movable end cover is fixedlyed connected with an end of adjustable lever, described adjustable lever passes described fixedly end cap, and described adjustable lever is connected with locating piece.
Further, described adjustable lever is a screw rod, and described locating piece is a locking nut.Certainly, also can select the mode of other adjustable levers and locating piece for use.
As preferred another kind of scheme: described valve pocket material selection copper base bearing metal, valve pocket is opened 4 notches vertically, and arc transition between the adjacent in twos notch forms dynamic pressure and slides lubricatedly at spool supporting shoulder place, on the valve port shoulder of spool balancing slit is arranged.
As preferred another scheme: spool and valve pocket notch be 165 °＜θ of angle＜180 ° radially.
As the another kind of scheme of preferred interchange valve: on the closed sides of spool notch, open triangular groove.
Technical conceive of the present utility model is: be made up of hydraulic oil source, interchange valve and flutter cylinder.The flutter cylinder is that single-acting does not have piston hydraulic cylinder, and structural feature is: the left side movable end can change the swept volume of oil hydraulic cylinder, thereby regulates frequency of the natural hydraulic mode; Right side elastic tip output vibration.Exchanging valve is that threeway profile shaft flow rotates selector valve, structural feature is: during valve core rotation, the valve port that two shoulders and valve pocket form in relevant position radially alternately opens and closes, control fluid output AC liquid stream, the innovative design of structural many places makes that to exchange valve working stability and noise when high frequency commutates little, has satisfied the requirement of flutter device dither.
During work, when valve core rotation during to position shown in Figure 1, pressure oil enters from the P mouth, the valve port that this moment, a pair of valve pocket window and spool notch formed is opened, and fluid enters valve inside and flows out from the A mouth through the valve pocket window, and promptly P-A is logical, pressure oil enters the flutter cylinder, and the distortion of oil hydraulic cylinder elastic tip is outstanding; When valve core rotation when the position shown in Figure 2, the valve port that P mouth place valve pocket window and spool notch form is closed, the valve port that A mouth place valve pocket window and spool notch form is opened, T-A is logical, the flutter cylinder takes back oil circuit, the oil hydraulic cylinder elastic tip is replied; Along with the continuous rotation of spool, valve port A and valve port P and T alternate conduction, the spool revolution can make and exchange valve commutation 12 times, and the oil hydraulic cylinder elastic tip produces flutter.
The beneficial effects of the utility model mainly show: 1. vibration frequency height.Conventional hydraulic vibration is to produce vibration by the hydraulic cylinder piston to-and-fro motion, because piston has certain quality and adds load, the high brief acceleration of frequency is big, inertial force and damping force are all very big, needing great restoring force to overcome inertial force vibrates, therefore, realize that the dither difficulty is very big.And being high-frequency ac liquid stream, this electrohydraulic fluttering device acts directly on the bigger hydraulic cylinder of elastic stiffness, make the elasticity end cap produce vibration, only need partly overcome the inertial force (load is vertically installed) of load and not have damping force, relend the elastic-restoring force that helps elastic element very big, can realize very high vibration frequency, vibration frequency depends primarily on the ripple frequency of alternating flow hydraulic stream.Innovative design at the part-structure that exchanges valve can make spool have very high running accuracy under high rotating speed, has guaranteed that the interchange valve exports high-frequency ac liquid stream reposefully.
2. specific power is big.This is the outstanding advantage of hydraulics, except that in oil sources, this electrohydraulic fluttering device by the flutter cylinder with exchange valve and form, volume is very little, but can export bigger power, and is high more a lot of than the power with the magnetic vibrator of volume.
3. micro breadth oscillation.The emergent property of elastic element has determined this electrohydraulic fluttering utensil that the characteristics of micro breadth oscillation are arranged.
4. energy-conservation.The flutter cylinder is designed to the volume adjustable structure, can change frequency of the natural hydraulic mode, when flutter cylinder generation resonance, only needs less power just can realize bigger amplitude.
5. price is low.The performance requirement of other element is not high except that exchanging valve, and therefore, electrohydraulic fluttering device system has compared price advantage with other vibration equipment.
Description of drawings
Fig. 1 is the schematic representation of the oil-feed state of high-frequency electrohydraulic fluttering generator.
Fig. 2 is the schematic representation of the oil return state of high-frequency electrohydraulic fluttering generator.
Fig. 3 is the A-A sectional view of Fig. 2.
Fig. 4 is the B-B sectional view of Fig. 2.
Fig. 5 is the I place structure unfolded drawing of Fig. 2.
Fig. 6 is the sectional view of the I place valve pocket of Fig. 2.
Fig. 7 is the II place valve port structural drawing of Fig. 2.
Fig. 8 is the II place valve core of Fig. 2 and the sectional view of valve pocket.
Embodiment
Below in conjunction with accompanying drawing the utility model is further described.
With reference to Fig. 1～Fig. 8, a kind of high-frequency electrohydraulic fluttering generator, comprise and exchange valve 1, flutter cylinder 2, described flutter cylinder 2 comprises cylinder body, described cylinder side wall has a turnover oilhole 3, described cylinder body one end installs and fixes end cap 4, and the other end of cylinder body is installed the elasticity end cap 5 that is connected with load, and described interchange valve 1 comprises valve body 9, valve pocket 10, spool 11 and drives the rotational power mechanism of valve core rotation and drive the sliding power mechanism that spool slides; Described valve body 9 is provided with an oil inlet P, an oil outlet A and an oil return inlet T, and described oil outlet A is communicated with described turnover oilhole 3, and described filler opening A and oil return inlet T are communicated with hydraulic oil source; Have the valve pocket that inserts for spool 11 in the described valve body 9, described spool 11 outer suit valve pockets 10 have 4 shoulders on the spool 11, and wherein two shoulders in the outside are for supporting shoulder, and inboard two shoulders are circumferentially evenly being processed Z respectively
1Individual notch, Z
1Be even number, the notch mutual dislocation on two shoulders; Valve pocket 10 is opened 4 group windows vertically, and the spacing between two shoulders of spacing between the adjacent window apertures and inboard equates that middle 1 group window is along circumferentially evenly offering Z
2Individual T type window, Z
2Be even number, Z
2=Z
1+ 2, Z is circumferentially evenly offered on 3 groups of edges, the outside
2Individual rectangular window, from the radial cross section direction, the position consistency of each group window.
Described flutter cylinder also comprises movable end cover 6 and adjustable lever 7, described movable end cover 6 is tightly connected with the sidewall of described cylinder body, described movable end cover 6 is fixedlyed connected with an end of adjustable lever 7, and described adjustable lever 7 passes described fixedly end cap 4, and described adjustable lever 7 is connected with locating piece 8.
Described adjustable lever 7 is a screw rod, and described locating piece 8 is a locking nut.Certainly, also can select the mode of other adjustable levers and locating piece for use.
Described valve pocket 10 material selection copper base bearing metals, valve pocket 10 is opened 4 notches vertically, arc transition between the adjacent in twos notch, it is lubricated to form the dynamic pressure slip at spool supporting shoulder place, on the valve port shoulder of spool balancing slit is arranged.
Spool and valve pocket notch be 165 °＜θ of angle＜180 ° radially.On the closed sides of full spool notch, open triangular groove.
The frequency of okperation f of electrohydraulic fluttering device equals to exchange the product of the spool rotation speed n of valve and the revolution break-make number of times m between spool notch and the valve pocket window, m=Z
1Z
2/ (Z
2-Z
1).
Be electrohydraulic fluttering device schematic diagram as shown in Figure 1 and Figure 2, system is made up of hydraulic oil source, interchange valve 1 and flutter cylinder 2.Flutter cylinder 2 does not have piston hydraulic cylinder for single-acting, and structural feature is: the left side movable end can change the swept volume of oil hydraulic cylinder, thereby regulates frequency of the natural hydraulic mode; Right side elastic tip output vibration.Exchange valve 1 and rotate selector valve for threeway profile shaft flow, structural feature is: two shoulders of spool and valve pocket are circumferentially evenly offered notch on edge, axial relevant position, the matching relationship of spool notch and valve pocket window as shown in Figure 3, Figure 4, notch mutual dislocation on spool two shoulders, spool notch number is 4, the valve pocket window number is 6, and the spool revolution can make and exchange valve commutation 12 times.
During work, the spool that exchanges valve 1 rotates continuously, and when valve core rotation during to position shown in Figure 1, P-A is logical, and pressure oil enters the flutter cylinder, and the distortion of oil hydraulic cylinder elastic tip is outstanding; When valve core rotation when the position shown in Figure 2, T-A is logical, the flutter cylinder takes back oil circuit, the oil hydraulic cylinder elastic tip is replied; Valve port A and valve port P and T alternate conduction, the oil hydraulic cylinder elastic tip produces flutter.Because the flow area of valve port size is directly proportional with the Face contact ratio that spool and valve pocket are linked up notch, can regulate amplitude by the axial displacement of control spool.The frequency of okperation f of electrohydraulic fluttering device equals to exchange the product of the spool rotation speed n of valve and the revolution break-make number of times m between spool notch and the valve pocket window.If the spool notch is counted Z
1With valve pocket window number Z
2Equate that after spool turned over several angle, valve port was all opened, and was open-shed, the break-make number of times of spool revolution is the spool notch and counts Z
1, flow area is whole valve port area sums, therefore, can pass through bigger flow, flutter device amplitude is relatively large.Improve frequency of okperation for making open-shed exchange valve, need on spool, open a large amount of notches, the valve core structure more complicated, diameter is bigger, and difficulty of processing also increases.If spool notch number and valve pocket window number are unequal, after spool turned over several angle, the part valve port was opened, and was the part open type, the break-make number of times of revolution.The flow area of part open type is littler than open-shed, but can satisfy the amplitude requirement of flutter device by the increase width of rebate.Because it is little to exchange the valve core rotation inertia of valve, be in again in the fine lubricating status, long-time high rotary speed working also is reliably, realizes on the engineering that the technical difficulty of electrohydraulic fluttering device dither is less.
With reference to Fig. 5～Fig. 8, there are rectangle oil groove and oil hole in valve pocket shown in Figure 5 place, total cross-section shown in Figure 6 total 90 ° of equally distributed 4 rectangle oil grooves and equally distributed 8 oil holes at interval pass through arc transition, and form certain store oil space between the rectangle oil groove.So, support the formation dynamic pressure slip of shoulder place at spool and lubricate, improve the critical whirling motion rotating speed of spool, thereby spool can both highi degree of accuracy be rotated in very big speed range.When the valve high speed rotating, ring-type oil slick thickness between spool and valve pocket is uneven, the radially power of surging that produces when a pair of valve port is opened is unequal, and the unbalanced masterpiece that radially surges is that external excitation acts on the spool, and the critical whirling motion rotating speed of spool is reduced.For this reason, if make radially 165 °＜θ of angle＜180 ° of spool and valve pocket notch, as the sectional view of valve core among Fig. 8 and valve pocket, the tangential component of certain momentum is arranged when making fluid enter valve pocket, thereby reduce the power of radially surging at valve port place.There are very large pressure jump the unlatching and the closed moment that exchange valve port, are the major reasons that produces air pocket, and air pocket largest when closed, shown in valve port among Fig. 7, here suppose that valve core rotates counterclockwise, when the right edge of valve core notch turned over the valve pocket window, valve port promptly was closed.For this reason, on the closed sides of spool notch, open triangular groove, make the valve port turn-off transient still have the triangular groove place to circulate, thereby can reduce the variation in pressure degree of valve port.
Claims (6)
1. high-frequency electrohydraulic fluttering generator, it is characterized in that: comprise exchanging valve and flutter cylinder, described flutter cylinder comprises cylinder body, described cylinder side wall has a turnover oilhole, described cylinder body one end installs and fixes end cap, the other end of cylinder body is installed the elasticity end cap that is connected with load, and described interchange valve comprises valve body, valve pocket, spool and drives the rotational power mechanism of valve core rotation and drive the sliding power mechanism that spool slides; Described valve body is provided with a filler opening, an oil outlet and a return opening, and described oil outlet is communicated with described turnover oilhole, and described filler opening and return opening are communicated with hydraulic oil source; Have the valve pocket that inserts for spool in the described valve body, suit valve pocket outside the described spool has 4 shoulders on the spool, and wherein two shoulders in the outside are the supporting shoulder, and inboard two shoulders are at circumferential even respectively processing Z
1Individual notch, Z
1Be even number, the notch mutual dislocation on two shoulders; Valve pocket is opened 4 group windows vertically, and the spacing between the adjacent window apertures equates that with spacing between the adjacent shoulder middle 1 group window is along circumferentially evenly offering Z
2Individual T type window, Z
2Be even number, Z
2=Z
1+ 2, Z is circumferentially evenly offered on 3 groups of edges, the outside
2Individual rectangular window, from the radial cross section direction, the position consistency of each group window.
2. high-frequency electrohydraulic fluttering generator as claimed in claim 1, it is characterized in that: described flutter cylinder also comprises movable end cover and adjustable lever, the sidewall of described movable end cover and described cylinder body is tightly connected, described movable end cover is fixedlyed connected with an end of adjustable lever, described adjustable lever passes described fixedly end cap, and described adjustable lever is connected with locating piece.
3. high-frequency electrohydraulic fluttering generator as claimed in claim 2 is characterized in that: described adjustable lever is a screw rod, and described locating piece is a locking nut.
4. as the described high-frequency electrohydraulic fluttering generator of one of claim 1～3, it is characterized in that: described valve pocket material selection copper base bearing metal, valve pocket is opened 4 notches vertically, arc transition between the adjacent in twos notch, it is lubricated to form the dynamic pressure slip at valve core supporting shoulder place, on the valve port shoulder of spool balancing slit is arranged.
5. high-frequency electrohydraulic fluttering generator as claimed in claim 4 is characterized in that: valve core and valve pocket notch be 165 °＜θ of angle＜180 ° radially.
6. the described high-frequency electrohydraulic fluttering generator of claim 4 is characterized in that: open triangular groove on the closed sides of spool notch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202216949U CN201836154U (en) | 2010-06-10 | 2010-06-10 | High-frequency electrohydraulic fluttering generator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202216949U CN201836154U (en) | 2010-06-10 | 2010-06-10 | High-frequency electrohydraulic fluttering generator |
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| CN201836154U true CN201836154U (en) | 2011-05-18 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101858373A (en) * | 2010-06-10 | 2010-10-13 | 浙江工业大学 | High-frequency electrohydraulic fluttering generator |
| CN102207111A (en) * | 2011-06-01 | 2011-10-05 | 武汉科技大学 | Composite flow valve |
| CN103321980A (en) * | 2013-06-24 | 2013-09-25 | 大连理工大学 | Area-gradient-variable digital rotary valve |
| CN106195336A (en) * | 2016-08-23 | 2016-12-07 | 衢州学院 | A kind of square wave excitation valve |
| CN111365315A (en) * | 2020-03-26 | 2020-07-03 | 浙江大学宁波理工学院 | Fault-tolerant vibrator |
-
2010
- 2010-06-10 CN CN2010202216949U patent/CN201836154U/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101858373A (en) * | 2010-06-10 | 2010-10-13 | 浙江工业大学 | High-frequency electrohydraulic fluttering generator |
| CN101858373B (en) * | 2010-06-10 | 2013-01-16 | 浙江工业大学 | High-frequency electrohydraulic fluttering generator |
| CN102207111A (en) * | 2011-06-01 | 2011-10-05 | 武汉科技大学 | Composite flow valve |
| CN102207111B (en) * | 2011-06-01 | 2013-06-05 | 武汉科技大学 | Composite flow valve |
| CN103321980A (en) * | 2013-06-24 | 2013-09-25 | 大连理工大学 | Area-gradient-variable digital rotary valve |
| CN103321980B (en) * | 2013-06-24 | 2015-11-18 | 大连理工大学 | A kind of Area-gradient-variabdigital digital rotary valve |
| CN106195336A (en) * | 2016-08-23 | 2016-12-07 | 衢州学院 | A kind of square wave excitation valve |
| CN111365315A (en) * | 2020-03-26 | 2020-07-03 | 浙江大学宁波理工学院 | Fault-tolerant vibrator |
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| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110518 Termination date: 20130610 |