CN101608965B - Single-screw hydraulic cylinder electrohydraulic vibration exciter - Google Patents
Single-screw hydraulic cylinder electrohydraulic vibration exciter Download PDFInfo
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- CN101608965B CN101608965B CN2009101008300A CN200910100830A CN101608965B CN 101608965 B CN101608965 B CN 101608965B CN 2009101008300 A CN2009101008300 A CN 2009101008300A CN 200910100830 A CN200910100830 A CN 200910100830A CN 101608965 B CN101608965 B CN 101608965B
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Abstract
The invention discloses a single-screw hydraulic cylinder electrohydraulic vibration exciter comprising a 2D electrohydraulic vibration valve, a single-screw hydraulic cylinder and a loading object, wherein, a piston is arranged in the body of the single-screw hydraulic cylinder; one side of the piston is fixedly connected with a piston rod, and one end of the piston rod extends out of the body of the single-screw hydraulic cylinder; the piston rod is connected with the loading object; a hydraulic fluid port of the inner cavity at one side of the piston in the cylinder body is communicated with a high-pressure oil tank, and the hydraulic fluid port of the inner cavity at the other side of the piston in the cylinder body is communicated with the oil inlet and outlet of the 2D electrohydraulic vibration valve; the 2D electrohydraulic vibration valve comprises a valve body, a valve core and a valve cover, wherein, the valve body is provided with an oil inlet communicated with the high-pressure oil tank, the oil inlet and outlet connected with the body of the single-screw hydraulic cylinder and an oil outlet connected with an oil return tank. The invention can effectively improve exciting frequency, reduces valve opening area amplitude attenuation along with the increase of the exciting frequency, has high energy efficiency, and has favourable antipollution performance.
Description
Technical field
The present invention relates to a kind of asymmetric servo cylinder vibrator.
Background technology
Vibration test is widely used in many important engineering field as the basic test of modern industry and the important means of research and development of products, as the road analogy test of automobile and walking machine; The antidetonation torture test of construction material, dam and skyscraper etc.
The mode of exciting mainly contains three types of mechanical type, electromagnetic type and electric-liquid types, and the mechanical shaker characteristics are: simple in structure, cost is low; But because physical construction limits, have that upper limiting frequency is lower, waveform distortion greatly and shortcoming such as mechanical clutter arranged.Electrodynamic vibration shaker has advantages such as waveform distortion is less, operating frequency range is big; But electrodynamic vibration shaker is difficult for obtaining big exciting force owing to be subjected to intrinsic magnetically saturated restriction, and in addition, device structure complexity, vibration displacement finite sum need radiator cooler.
Electrohydraulic excitation is compared with the former two has the advantage that exciting power is big, thrust big, can realize multi-point exciting, is mainly used in heavy duty, powerful occasion.The principle of work of existing electric-liquid type exciting (as shown in Figure 1) is by electrohydraulic servo valve input accumulation signal control hydraulic actuator (oil cylinder or motor) is done toward complex line or twisting motion, and then makes and execute the object starting of oscillation of shaking.Electric liquid by this principle work swashs the frequency range that its excited frequency of device is decided by electrohydraulic servo valve to a great extent.Be subjected to the restriction of servo-valve work structuring and Frequency Response, mainly have the following disadvantages: (1) its excited frequency generally in 80HZ, is difficult to improve; (2) valve aperture area amplitude is more serious with the raising attenuation ratio of excited frequency; (3) servo-valve generally adopts the pilot-operated type multilevel hierarchy, has zero leakage, and the pilot stage energy loss is serious, and energy efficient capacity is low.(4) nozzle-flapper servo valve or jet pipe servo valve are to the lustration class height of fluid, and antipollution is poor.
Summary of the invention
Lower for the excited frequency that overcomes existing asymmetric servo cylinder vibrator, valve aperture area amplitude is serious with the raising attenuation ratio of excited frequency, energy efficient capacity is low, the deficiency of antifouling property difference, the invention provides a kind ofly can effectively improve excited frequency, reduce valve aperture area amplitude with the decay of the raising of excited frequency, energy efficient capacity height, single-screw hydraulic cylinder electrohydraulic vibration exciter that antifouling property is good.
The technical solution adopted for the present invention to solve the technical problems is:
A kind of single-screw hydraulic cylinder electrohydraulic vibration exciter, comprise 2D electrohydraulic excitation valve, asymmetric servo cylinder and loading object, be provided with piston in the cylinder body of described asymmetric servo cylinder, described piston one side is fixedlyed connected with piston rod, one end of piston rod stretches out outside the cylinder body of described asymmetric servo cylinder, described piston rod is connected with described loading object, the hydraulic fluid port of the inner chamber of piston one side is communicated with pressure-oil tank in the described cylinder body, and the hydraulic fluid port of the inner chamber of piston opposite side is communicated with the oil inlet and outlet of described electrohydraulic excitation device in the described cylinder body;
Described 2D electrohydraulic excitation valve comprises valve body, spool and valve pocket, the oil-out that has the import oil that is communicated with pressure-oil tank, the import and export that link to each other with the cylinder body of asymmetric servo cylinder oil on the described valve body and link to each other with the oil return fuel tank; Described valve pocket is nested in the inwall of valve body, described spool passes valve pocket, described spool is connected with axially movable second servomotor of driver's valve core with first servomotor that is used to drive the spool rotation, described spool is provided with first shoulder and second shoulder, described first shoulder and second shoulder circumferentially evenly offer at least two grooves, the groove mutual dislocation on first shoulder and second shoulder; The circumferential circle valve pocket window that cooperates with each shoulder that evenly offers of described valve pocket, described valve pocket window comprises the first valve pocket window, the second valve pocket window, valve pocket between adjacent valve pocket window is provided with assistant window, is provided with additional window in the valve pocket end near the first valve pocket window; Described additional window is communicated with described oil-out, and described first valve pocket window and assistant window are communicated with oil inlet and outlet, and described second valve pocket window and oil-in are communicated with.
Further, the groove number on the window number of a described circle valve pocket window and the shoulder is approximate number each other, and one to enclose the window number of valve pocket window and the groove number on shoulder be integer greater than 1.
Or: the groove number on the window number of a circle valve pocket window and the shoulder be the integer greater than 1, and the absolute value of difference is one to enclose the window number of valve pocket window and the approximate number of the groove number on the shoulder between the window number of a described circle valve pocket window and the groove number on the shoulder.
Further again, the window number of a described circle valve pocket window is bigger than the groove number on the shoulder.
Further, circumferentially evenly offer described assistant window and additional window at valve pocket.
Groove number on described each shoulder is four, six, eight or 16.
Technical conceive of the present invention is: adopt spool rotation and axial double freedom to design.Spool is rotated by driven by servomotor in operation valve, make the valve port area size one-tenth cyclical variation that the groove (central angle of adjacent trenches is θ) circumferentially evenly offered along spool land matches with window on the valve pocket, because the groove mutual dislocation (the dislocation angle is θ/2) on the adjacent shoulder, thereby make that the flow size of the cavity volume that liquid in-out cylinder pressure piston end surface area is bigger and direction are the variation of 180 ° of generating periods with phase differential, drive hydraulic actuator list rod hydraulic stem and do periodic to-and-fro movement, and then the loading object that drive links to each other with single rod hydraulic stem piston rod is done vibration back and forth.
When spool is positioned at position shown in Figure 2 in rotation process, P mouth and C oral groove are logical, hydraulic cylinder B mouth links to each other with the C mouth, hydraulic cylinder chamber, a left side (piston area is than small end) is permanent to be communicated with pressure-oil tank, right chamber (the bigger end of piston area) oil-feed, though the pressure in hydraulic cylinder two chambeies equates that because of there is area difference in the piston two ends, oil cylinder piston is to left movement; θ/when 2 angles were in position shown in Figure 3, C mouth and T oral groove were logical when spool rotates through, and hydraulic cylinder B mouth links to each other with the C mouth, and hydraulic cylinder chamber, a left side (piston area is than small end) is permanent to be communicated with pressure-oil tank, right chamber (the bigger end of piston area) oil return, and oil cylinder piston moves right.When spool rotates under driven by servomotor, oil cylinder piston will be done periodic to-and-fro movement and produce exciting.
In the electrohydraulic excitation valve, the area that window constitutes on groove on the shoulder and the valve pocket is except that rotating the generating period variation because of spool, and the amplitude of its variation realizes stepless control from zero (valve port is closed fully) to maximum by the axially-movable of spool.Spool axially-movable drive spool by another servomotor by eccentric stiffener and realize, thereby change the periodically variable amplitude of valve port area by the size of controlling this servomotor corner, and then change the vibration amplitude (thrust output) of hydraulic cylinder.
The frequency of operation that electrohydraulic excitation valve control hydraulic pressure shown in Figure 2 is carried out first electrohydraulic excitation device that is constituted is directly proportional with the rotating speed of spool.Because spool is a slim-lined construction, moment of inertia is very little, is in again in the fine lubricating status of hydraulic oil, thereby is easy to improve the high excited frequency of rotational speed acquisition of spool.
The frequency of operation f of electro hydraulic valve control vibrator equals the rotation rotation speed n of spool and the product of the communication number of times m between spool groove revolution and the valve pocket window.Thereby except that passing through to improve the rotating speed raising frequency of operation of spool, can also be by increasing the groove number on the spool land and selecting the matching relationship between spool and the valve pocket improve spool groove and valve pocket window revolution communication number of times.The spool revolution is linked up number of times m and is removed that to count Z relevant, also relevant with the matching relationship of spool groove and valve pocket window with the spool groove.If the window number of a circle valve pocket window can be divided exactly by the groove number on the shoulder, or the groove number on shoulder can be divided exactly by the window number of a circle valve pocket window, and then this fit form is called open-shed, as shown in Figure 4 and Figure 5.The break-make number of times of open-shed spool revolution is the spool groove and counts Z (valve pocket window number).If spool groove number and valve pocket window number are unequal, then this fit form is called the part open-type, as shown in Figure 6 and Figure 7.The break-make number of times of part open-type valve core revolution equals the product that the spool groove is counted Z and " umber of beats ", " umber of beats " equals the ratio (spool groove number and valve pocket window number must be selected suitable value, thereby guarantee that umber of beats is an integer) of spool groove number and spool groove number and valve pocket window number difference.Fig. 6 spool groove is 8, and the valve pocket window number is 10, and the spool revolution is linked up 32 times.The electrohydraulic excitation device that adopts valve to constitute as can be seen by above brief analysis is easy to realize high-frequency excitation.
The frequency f of electrohydraulic excitation valve equals rotation speed n and the spool groove of revolution and the product between the communication number of times m between the valve pocket window of spool, that is:
f＝n×m
For open-shed, m equals the big person of spool groove number and valve pocket window number; For the part open-type, m equals the ratio of the difference of the big person of spool groove number and valve pocket window number and spool groove number and valve pocket window number.
Beneficial effect of the present invention mainly shows: 1, can increase substantially the electrohydraulic excitation frequency; 2, reduce valve aperture area amplitude well with the decay of the raising of excited frequency; 3, energy efficient capacity height; 4, antifouling property is good.
Description of drawings
Fig. 1 is existing hydraulic exciting schematic diagram.
Fig. 2 is first working state schematic representation of electrohydraulic excitation device of the present invention.
Fig. 3 is second working state schematic representation of electrohydraulic excitation device of the present invention.
Fig. 4 is a kind of spool of open-shed electrohydraulic excitation controlling valve and the synoptic diagram of valve pocket window.
Fig. 5 is the spool of another kind of open-shed electrohydraulic excitation controlling valve and the synoptic diagram of valve pocket window.
Fig. 6 is a kind of spool of part open-type electrohydraulic excitation controlling valve and the synoptic diagram of valve pocket window.
Fig. 7 is the spool of another kind of part open-type electrohydraulic excitation controlling valve and the synoptic diagram of valve pocket window.
Embodiment
Below in conjunction with accompanying drawing the present invention is further described.
With reference to Fig. 1～Fig. 7, a kind of single-screw hydraulic cylinder electrohydraulic vibration exciter comprises electrohydraulic excitation valve 8, asymmetric servo cylinder 3 and loads object 5; Described electrohydraulic excitation valve 8 is connected with described asymmetric servo cylinder 3, described asymmetric servo cylinder 3 is connected with described loading object 5, one end of described asymmetric servo cylinder 5 pistons stretches out hydraulic cylinder, there is area difference in the area on piston two sides, a hydraulic fluid port is respectively arranged at the hydraulic cylinder piston two ends, area than the hydraulic fluid port of small end and high pressure mailbox together with, the hydraulic fluid port of the big section of area is communicated with the oil inlet and outlet of affiliated electrohydraulic excitation device.Described electrohydraulic excitation valve 8 comprises valve body, has the import oil P that is communicated with the high pressure mailbox on the described valve body, the import and export that are communicated with hydraulic cylinder oil C, the oil-out T that links to each other with the oil return mailbox.This electrohydraulic excitation controlling valve also comprises spool 13 and valve pocket 12, described valve pocket 12 is nested in the inwall of valve body, described spool 13 passes valve pocket 12, and described spool 13 is connected with axially movable second servomotor of driver's valve core with first servomotor that is used to drive the spool rotation; Described spool 13 is provided with at least two shoulders, and what comprise first shoulder 10, second shoulder, 11 described each shoulders circumferentially evenly offers at least two grooves, the groove mutual dislocation on the adjacent shoulder; The circumferential circle valve pocket window that cooperates with each shoulder that evenly offers of described valve pocket 12, described valve pocket window is at least two circles, comprise the first valve pocket window 6, the second valve pocket window 1, valve pocket between adjacent valve pocket window is provided with assistant window 2, is provided with additional window 7 in the valve pocket end near the first valve pocket window; Described additional window 7 is communicated with described oil-out T, and described first valve pocket window 6 and assistant window 2 are communicated with oil inlet and outlet C, the described second valve pocket window 1 and be communicated with oil-in C.
Groove number on the window number of a described circle valve pocket window and the shoulder is approximate number each other.The absolute value of difference is the window number of a circle valve pocket window and the approximate number of the groove number on the shoulder between the window number of a described circle valve pocket window and the groove number on the shoulder.Groove number on the window number of one circle valve pocket window and the shoulder is the integer greater than 1.The window number of a described circle valve pocket window is bigger than the quantity of the groove on the shoulder.
Circumferentially evenly offer described assistant window and additional window at valve pocket.Groove number on described each shoulder is four, six, eight or 16.
If the window number of a circle valve pocket window can be divided exactly by the groove number on the shoulder, or the groove number on shoulder can be divided exactly by the window number of a circle valve pocket window, and then this fit form is called open-shed, as Fig. 4, shown in Figure 5.The break-make number of times of open-shed spool revolution is the spool groove and counts Z (valve pocket window number).If spool groove number and valve pocket window number are unequal, then this fit form is called the part open-type, as Fig. 6, shown in Figure 7.The break-make number of times of part open-type valve core revolution equals the product that the spool groove is counted Z and " umber of beats ", " umber of beats " equals the ratio (spool groove number and valve pocket window number must be selected suitable value, thereby guarantee that umber of beats is an integer) of spool groove number and spool groove number and valve pocket window number difference.Fig. 7 spool groove is 8, and the valve pocket window number is 10, and the spool revolution is linked up 32 times.
The course of work of present embodiment is: when spool is positioned at position shown in Figure 2 in rotation process, P mouth and C oral groove are logical, hydraulic cylinder B mouth links to each other with the C mouth, hydraulic cylinder chamber, a left side (piston area is than small end) is permanent to be communicated with pressure-oil tank, right chamber (the bigger end of piston area) oil-feed, though the pressure in hydraulic cylinder two chambeies equates that because of there is area difference in the piston two ends, oil cylinder piston is to left movement; θ/when 2 angles were in position shown in Figure 3, C mouth and T oral groove were logical when spool rotates through, and hydraulic cylinder B mouth links to each other with the C mouth, and hydraulic cylinder chamber, a left side (piston area is than small end) is permanent to be communicated with pressure-oil tank, right chamber (the bigger end of piston area) oil return, and oil cylinder piston moves right.When spool rotates under driven by servomotor, oil cylinder piston will be done periodic to-and-fro movement and produce exciting.
In the electrohydraulic excitation valve, the area that window constitutes on groove on the shoulder and the valve pocket is except that rotating the generating period variation because of spool, and the amplitude of its variation realizes stepless control from zero (valve port is closed fully) to maximum by the axially-movable of spool.Spool axially-movable drive spool by another servomotor by eccentric stiffener and realize, thereby change the periodically variable amplitude of valve port area by the size of controlling this servomotor corner, and then change the vibration amplitude (thrust output) of hydraulic cylinder.
Claims (6)
1. single-screw hydraulic cylinder electrohydraulic vibration exciter, it is characterized in that: described single-screw hydraulic cylinder electrohydraulic vibration exciter comprises 2D electrohydraulic excitation valve, asymmetric servo cylinder and loading object, be provided with piston in the cylinder body of described asymmetric servo cylinder, described piston one side is fixedlyed connected with piston rod, one end of piston rod stretches out outside the cylinder body of described asymmetric servo cylinder, described piston rod is connected with described loading object, the hydraulic fluid port of the inner chamber of piston one side is communicated with pressure-oil tank in the described cylinder body, and the hydraulic fluid port of the inner chamber of piston opposite side is communicated with the oil inlet and outlet of described 2D electrohydraulic excitation valve in the described cylinder body; Described 2D electrohydraulic excitation valve comprises valve body, spool and valve pocket, the oil-out that has the import oil that is communicated with pressure-oil tank, the import and export that link to each other with the cylinder body of asymmetric servo cylinder oil on the described valve body and link to each other with the oil return fuel tank; Described valve pocket is nested in the inwall of valve body, described spool passes valve pocket, described spool is connected with axially movable second servomotor of driver's valve core with first servomotor that is used to drive the spool rotation, described spool is provided with first shoulder and second shoulder, described first shoulder and second shoulder circumferentially evenly offer at least two grooves, the groove mutual dislocation on first shoulder and second shoulder; The circumferential circle valve pocket window that cooperates with each shoulder that evenly offers of described valve pocket, described valve pocket window comprises the first valve pocket window, the second valve pocket window, valve pocket between adjacent valve pocket window is provided with assistant window, is provided with additional window in the valve pocket end near the first valve pocket window; Described additional window is communicated with described oil-out, and described first valve pocket window and assistant window are communicated with oil inlet and outlet, and described second valve pocket window and oil-in are communicated with.
2. single-screw hydraulic cylinder electrohydraulic vibration exciter as claimed in claim 1, it is characterized in that: the window number of a described circle valve pocket window can be divided exactly by the groove number on the shoulder, groove number on the perhaps described shoulder can be divided exactly by the window number of a circle valve pocket window, and the groove number on the window number of a circle valve pocket window and the shoulder is the integer greater than 1.
3. single-screw hydraulic cylinder electrohydraulic vibration exciter as claimed in claim 1, it is characterized in that: the groove number on the window number of a circle valve pocket window and the shoulder is for greater than 1 integer, and the absolute value of difference is one to enclose the window number of valve pocket window and the approximate number of the groove number on the shoulder between the window number of a described circle valve pocket window and the groove number on the shoulder.
4. as the described single-screw hydraulic cylinder electrohydraulic vibration exciter of one of claim 1-3, it is characterized in that: the window number of a described circle valve pocket window is bigger than the groove number on the shoulder.
5. as the described single-screw hydraulic cylinder electrohydraulic vibration exciter of one of claim 1-3, it is characterized in that: circumferentially evenly offer described assistant window and additional window at valve pocket.
6. as the described single-screw hydraulic cylinder electrohydraulic vibration exciter of one of claim 1-3, it is characterized in that: the groove number on described each shoulder is four, six, eight or 16.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2009101008300A CN101608965B (en) | 2009-07-13 | 2009-07-13 | Single-screw hydraulic cylinder electrohydraulic vibration exciter |
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| CN2009101008300A CN101608965B (en) | 2009-07-13 | 2009-07-13 | Single-screw hydraulic cylinder electrohydraulic vibration exciter |
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| CN101608965B true CN101608965B (en) | 2011-02-09 |
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| CN102734279B (en) * | 2012-06-28 | 2014-12-10 | 浙江大学 | Electrohydraulic vibration exciter |
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