液壓油路電磁閥工作原理課件

1、,PROPORTIONAL VALVES - BASIC PRINCIPLES,Copyright Eaton Hydraulics 2000,Steve Skinner, Eaton Hydraulics, Havant, UK,比例閥基本原理,1,學(xué)習(xí)交流PPT,BASIC SYSTEM,1) 一般認(rèn)為一個簡單的液壓系統(tǒng)由油箱（A）、電動機(jī)（B）、泵（C）、溢流閥（D）、過濾器（E）、流量控制閥（F）、方向控制閥（G）、和油缸（H）組成。,2) 油缸的運(yùn)動是由流量控制閥（確定運(yùn)動的速度）和方向控制閥（油缸運(yùn)動的方向）控制。,A,B,C,D,E,F,H,G,2,學(xué)習(xí)交流PPT,BASIC S

2、YSTEM,當(dāng)電磁閥得電時，油缸活塞將伸出和回縮,其速度由流量控制閥確定，而電磁閥不具有控制速度的能力。,3,學(xué)習(xí)交流PPT,BASIC SYSTEM,A three position solenoid valve can: - extend the cylinder,4,學(xué)習(xí)交流PPT,BASIC SYSTEM,A three position solenoid valve can: - extend the cylinder - retract the cylinder,5,學(xué)習(xí)交流PPT,BASIC SYSTEM,A three position solenoid valve can:

3、- extend the cylinder - retract the cylinder - stop the cylinder,6,學(xué)習(xí)交流PPT,因此電磁閥的動作非常象一個電路中的開關(guān) 在此位置燈是關(guān)閉狀態(tài).,7,學(xué)習(xí)交流PPT,. 在另外一個位置是開啟狀態(tài)，而沒有中間狀態(tài)。 and in the other position it is switched on but there are no intermediate states.,8,學(xué)習(xí)交流PPT,然而眾所周知，另一種形式的開關(guān)能夠用來控制燈泡，調(diào)光開關(guān) However, another type of switch can be

4、 used for controlling a light bulb known as a dimmer switch.,9,學(xué)習(xí)交流PPT,在這個例子中，這個開關(guān)能夠被轉(zhuǎn)到全開和全關(guān)的任一位置，來調(diào)整燈泡的亮度 In this case, the switch can be turned to any position between fully off and fully on to vary the brightness of the bulb.,10,學(xué)習(xí)交流PPT,In this case, the switch can be turned to any position betwe

5、en fully off and fully on to vary the brightness of the bulb.,11,學(xué)習(xí)交流PPT,In this case, the switch can be turned to any position between fully off and fully on to vary the brightness of the bulb.,12,學(xué)習(xí)交流PPT,In this case, the switch can be turned to any position between fully off and fully on to vary

6、the brightness of the bulb.,13,學(xué)習(xí)交流PPT,In this case, the switch can be turned to any position between fully off and fully on to vary the brightness of the bulb.,14,學(xué)習(xí)交流PPT,In this case, the switch can be turned to any position between fully off and fully on to vary the brightness of the bulb.,15,學(xué)習(xí)交

7、流PPT,在這個例子中，這個開關(guān)能夠被轉(zhuǎn)到全開和全關(guān)的任一位置，來調(diào)整燈泡的亮度。 In this case, the switch can be turned to any position between fully off and fully on to vary the brightness of the bulb.,16,學(xué)習(xí)交流PPT,In this case, the switch can be turned to any position between fully off and fully on to vary the brightness of the bulb.,17,

8、學(xué)習(xí)交流PPT,BASIC SYSTEM,2) 閥芯能夠移動到在任一位置，而不僅僅是三個不連續(xù)的位置。 閥芯在離開中位的方向仍然確定油缸運(yùn)動的方向，但閥芯離開中位的距離控制活塞的速度。,1) 比例方向閥能夠被看作與調(diào)光開關(guān)具有同樣功能。 A proportional directional valve can be thought of as the dimmer switch equivalent of an electrical switch.,18,學(xué)習(xí)交流PPT,BASIC SYSTEM,于是在實際上比例閥可以同時作為方向閥和流量閥來使用。 So in effect the propo

9、rtional directional valve is acting as both a directional valve and a flow control valve.,19,學(xué)習(xí)交流PPT,SWITCHING SOLENOID VALVE,一個傳統(tǒng)的電磁閥能夠被認(rèn)為是一個簡單的開關(guān)閥。 A conventional solenoid valve can be thought of as a simple switching valve. 它可以被一些只有簡單電流通斷的開關(guān)的電設(shè)備來控制 It is controlled by some form of electrical devi

10、ce which simply switches the electrical current on or off.,20,學(xué)習(xí)交流PPT,SWITCHING SOLENOID VALVE,A conventional solenoid valve can be thought of as a simple switching valve. It is controlled by some form of electrical device which simply switches the electrical current on or off.,21,學(xué)習(xí)交流PPT,SWITCHING

11、SOLENOID VALVE,A conventional solenoid valve can be thought of as a simple switching valve. It is controlled by some form of electrical device which simply switches the electrical current on or off.,22,學(xué)習(xí)交流PPT,PROPORTIONAL VALVE,一個比例方向閥是由與一個與調(diào)光開關(guān)非常象的電設(shè)備控制的。 A proportional directional valve however w

12、ill be controlled by an electrical device more like a dimmer switch.,23,學(xué)習(xí)交流PPT,PROPORTIONAL VALVE,通過改變兩個之一電磁鐵的電流，閥芯移動的位移能夠被改變，因此控制了通過閥的流量。 By varying the current to either solenoid, the amount of spool movement can be varied and hence the amount of flow through the valve can be controlled.,24,學(xué)習(xí)交流P

13、PT,PROPORTIONAL VALVE,By varying the current to either solenoid, the amount of spool movement can be varied and hence the amount of flow through the valve can be controlled.,25,學(xué)習(xí)交流PPT,PROPORTIONAL VALVE,By varying the current to either solenoid, the amount of spool movement can be varied and hence

14、the amount of flow through the valve can be controlled.,26,學(xué)習(xí)交流PPT,PROPORTIONAL VALVE,By varying the current to either solenoid, the amount of spool movement can be varied and hence the amount of flow through the valve can be controlled.,27,學(xué)習(xí)交流PPT,PROPORTIONAL VALVE,By varying the current to either

15、 solenoid, the amount of spool movement can be varied and hence the amount of flow through the valve can be controlled.,28,學(xué)習(xí)交流PPT,PROPORTIONAL VALVE,By varying the current to either solenoid, the amount of spool movement can be varied and hence the amount of flow through the valve can be controlled

16、.,29,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,因此不像傳統(tǒng)的電磁閥，通過比例閥線圈的電流需要被調(diào)整，而不僅僅是開關(guān)式的通斷。 比例閥電磁鐵的結(jié)構(gòu)與開關(guān)式電磁鐵是相似的。 電磁鐵包括: - 線圈 (A) - 框架 (B) - 電樞 (C) - 電極片 (D) - 頂針 (E) 電樞被 包在一個芯軸管（F）中。 (同時全部的總成經(jīng)常被壓進(jìn)一個樹脂塑料的外罩（G）中）,A,B,C,D,F,G,E,30,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,When a voltage is applied to the coil connections, an elec

17、trical current will flow through the coil.,31,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,1) 接下來，電流生成一個磁場，磁場主要集中在金屬框架、電機(jī)片和電樞中 In turn, the electrical current creates a magnetic field which is concentrated in the metal frame, pole piece and armature.,2) 然而在磁回路的電機(jī)片和電樞之間有一個間隙，于是產(chǎn)生一個力，其作用是關(guān)閉這個間隙以完成這個磁回路。 There is how

18、ever a gap in the magnetic circuit between the pole piece and armature so a force is created which acts to close this gap and complete the magnetic circuit.,32,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,1)頂針連接著電磁鐵和閥芯，通常移動閥芯壓縮彈簧。 The push-pin connects the solenoid to the valve spool and normally moves the spool a

19、gainst a spring.,2) 電磁鐵產(chǎn)生的力The 大小由磁場強(qiáng)度決定，磁場強(qiáng)度與通過線圈的電流成比例 force created by the solenoid is determined by the strength of the magnetic field which itself is proportional to the current flowing through the coil.,33,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,增大線圈電流將加大電磁的力，因此推動閥芯壓縮彈簧產(chǎn)生一個更大的位移。 Increasing the coil cur

20、rent will increase the solenoid force and hence move the spool a greater amount against the spring.,34,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,Increasing the coil current will increase the solenoid force and hence move the spool a greater amount against the spring.,35,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,Increasing

21、the coil current will increase the solenoid force and hence move the spool a greater amount against the spring.,36,學(xué)習(xí)交流PPT,PROPORTIONAL SOLENOID,電磁鐵被設(shè)計成電磁力(F)與線圈電流(I)成線性比例關(guān)系。這意味著電磁力僅與線圈電流有關(guān)。,37,學(xué)習(xí)交流PPT,開關(guān)電磁閥閥芯,比例閥與開關(guān)電磁閥之間的另一個區(qū)別是閥芯的設(shè)計。 A further difference between a switching solenoid valve and a pro

22、portional valve is in the design of the spool.,38,學(xué)習(xí)交流PPT,SWITCHING SOLENOID SPOOL,1) 對于開關(guān)閥，閥芯被設(shè)計為當(dāng)閥得電時，將壓降最小化。,2)這意味著，控制小流量 閥開口要求非常小并且很困難。 Which would mean that to control low flow rates, the amount of spool opening required would be very small and difficult to control.,39,學(xué)習(xí)交流PPT,S,S,Q,PROPORTIONA

23、L SPOOL,1) 比例閥閥芯具有比較寬的邊緣帶有槽口的臺肩。 A proportional valve spool therefore has wider lands with notches cut into the edges.,40,學(xué)習(xí)交流PPT,S,S,Q,PROPORTIONAL SPOOL,2) 因此盡管通過閥的最大流量被減少了（與開關(guān)閥對照）但小流量特別容易控制，閥的開口更有規(guī)則。 So although the maximum flow through the valve may be reduced (compared to a switching valve) low

24、 flows in particular are more easily controlled and the opening of the valve is more gradual.,1) 比例閥閥芯具有比較寬的邊緣帶有槽口的臺肩。,41,學(xué)習(xí)交流PPT,S,S,Q,PROPORTIONAL SPOOL,依據(jù)控制的最大流量，不同的閥芯能被適用于不同形狀、大小或閥芯槽口的大小特定的閥 Depending upon the maximum flow to be controlled, different spools can be fitted to a particular valve wh

25、ich have different shape, size or number of spool notches.,42,學(xué)習(xí)交流PPT,直動式比例溢流閥,1)比例閥也可以被用來控制壓力。在此比例電磁鐵被用來推動一個錐閥芯通過一個彈簧壓縮閥座。電磁力越大，推開錐閥芯離開閥座打開閥的壓力要求越大。 Proportional valves can also be used to control pressure. In this case a proportional solenoid is used to push a poppet against a seat via a spring. T

26、he greater the solenoid force the greater the pressure required to push the poppet off its seat and open the valve.,43,學(xué)習(xí)交流PPT,DIRECT ACTING PROPORTIONAL RELIEF VALVE,2) 這里提供一個直動式溢流閥功能，但象多數(shù)此類閥一樣，只能允許一個小流量通過該閥。 This provides a direct acting relief valve function but like most such valves, it is only

27、possible to pass small flow rates through the valve.,1)比例閥也可以被用來控制壓力。在此比例電磁鐵被用來推動一個錐閥芯通過一個彈簧壓縮閥座。電磁力越大，推開錐閥芯離開閥座打開閥的壓力要求越大。 Proportional valves can also be used to control pressure. In this case a proportional solenoid is used to push a poppet against a seat via a spring. The greater the solenoid fo

28、rce the greater the pressure required to push the poppet off its seat and open the valve.,44,學(xué)習(xí)交流PPT,兩-級比例溢流閥,為控制大流量，直動式比例溢流閥能被用來作為一個兩級溢流閥（或減壓閥）的先導(dǎo)級 To control higher flow rates, the proportional direct acting relief valve can be used as the pilot stage of a two-stage relief (or reducing valve).,45,

29、學(xué)習(xí)交流PPT,TWO-STAGE PROPORTIONAL RELIEF VALVE,To control higher flow rates, the proportional direct acting relief valve can be used as the pilot stage of a two-stage relief (or reducing valve).,46,學(xué)習(xí)交流PPT,BENEFITS OF PROPORTIONAL SYSTEMS,比例系統(tǒng)的優(yōu)點(diǎn),47,學(xué)習(xí)交流PPT,遠(yuǎn)程控制 傳統(tǒng)系統(tǒng),在常規(guī)系統(tǒng)中為了調(diào)整執(zhí)行器的速度，流量控制閥必須安裝在一個方便的或便于

30、接近的位置，這意味著與操縱臺連接的液壓管路經(jīng)常運(yùn)行在高壓下。,48,學(xué)習(xí)交流PPT,遠(yuǎn)程控制 比例系統(tǒng),對于比例系統(tǒng)，控制閥為電子調(diào)節(jié)，僅需要低功率的電纜連接操縱臺和比例閥即可。 With a proportional system however, where control valve adjustment is electronic, only low-power electrical cables need to be connected between the operators desk and the valve.,49,學(xué)習(xí)交流PPT,PLC 遠(yuǎn)程控制 比例系統(tǒng),今天更多的是，

31、機(jī)械控制被數(shù)字電子控制所取代，這里情況也是一樣，比例閥的電子控制能力為液壓系統(tǒng)和電子控制器之間提供一個簡單的接口。,50,學(xué)習(xí)交流PPT,比例壓力控制,使用比例方向和壓力控制閥意味著機(jī)器的所有液壓功能（運(yùn)動和力）能被電子地控制。,51,學(xué)習(xí)交流PPT,電磁閥的反應(yīng)時間 SOLENOID VALVE RESPONSE TIME,A further benefit of proportional valves is the ability to electronically control the speed of operation of the valve. 比例閥地進(jìn)一步功能是電子控制閥操作

32、速度的能力。,52,學(xué)習(xí)交流PPT,0.015,S,SOLENOID VALVE RESPONSE TIME,Depending upon its size and voltage supply, a conventional switching solenoid valve will have an energisation response time of approximately 15 milli-seconds. 依據(jù)閥的大小和提供的電壓，一個傳統(tǒng)的開關(guān)電磁閥對于一個得電動作的反應(yīng)時間是15毫秒。,53,學(xué)習(xí)交流PPT,0.040,S,SOLENOID VALVE RESPONSE

33、TIME,The de-energisation response time will be only slightly slower (typically around 25 ms) since the return spring produces less force than the solenoid . 由于回程彈簧的力小于電磁鐵，斷電的反應(yīng)時間稍慢（通常25ms左右），,54,學(xué)習(xí)交流PPT,S,比例閥的反應(yīng)時間 PROPORTIONAL VALVE RESPONSE TIME,比例閥閥芯的運(yùn)動速度能被閥電磁鐵的供給電子信號確定。通過逐漸地增加或降低信號（叫做斜坡）可以完成幾秒的得電

34、和斷電時間。 The speed ofmovement of a proportional valve spool however can be determined by the electronic signal fed to the valve solenoid. By gradually increasing or decreasing the the signal (known as ramping), it is possible to achieve energisation and de-energisation response times of several second

35、s.,55,學(xué)習(xí)交流PPT,1.000,S,PROPORTIONAL VALVE RESPONSE TIME,比例閥閥芯的運(yùn)動速度能被閥電磁鐵的供給電子信號確定。通過逐漸地增加或降低信號（叫做斜坡）可以完成幾秒的得電和斷電時間。,56,學(xué)習(xí)交流PPT,2.000,S,PROPORTIONAL VALVE RESPONSE TIME,比例閥閥芯的運(yùn)動速度能被閥電磁鐵的供給電子信號確定。通過逐漸地增加或降低信號（叫做斜坡）可以完成幾秒的得電和斷電時間。,57,學(xué)習(xí)交流PPT,3.000,S,PROPORTIONAL VALVE RESPONSE TIME,比例閥閥芯的運(yùn)動速度能被閥電磁鐵的供給電子

36、信號確定。通過逐漸地增加或降低信號（叫做斜坡）可以完成幾秒的得電和斷電時間。,58,學(xué)習(xí)交流PPT,頂升舉例-傳統(tǒng)系統(tǒng) LIFT EXAMPLE - CONVENTIONAL SYSTEM,為什么控制閥的閥芯運(yùn)動速度是用用處的原因是減少系統(tǒng)中的震動，這可以通過控制執(zhí)行器的加速和減速來完成。假設(shè)舉例，一個簡單的液壓系統(tǒng)被用于賓館中的乘客電梯操作，比較容易說明。,59,學(xué)習(xí)交流PPT,頂升舉例-傳統(tǒng)系統(tǒng) LIFT EXAMPLE - CONVENTIONAL SYSTEM,.當(dāng)這磁閥得電降低電梯時，閥芯將快速運(yùn)動，這意味著油缸將極快地加速到其最大速度（最大速度由控制閥F的設(shè)置確定），這個突然的啟動

37、會給電梯乘客一個極不舒服的感受。,F,60,學(xué)習(xí)交流PPT,頂升舉例-傳統(tǒng)系統(tǒng) LIFT EXAMPLE - CONVENTIONAL SYSTEM,同樣地,當(dāng)電梯達(dá)到終點(diǎn)時，電磁閥將非?？斓仃P(guān)閉產(chǎn)生一個突然地 停止，當(dāng)然又是一個極不舒服地動作。在一個真正地液壓系統(tǒng)中，由于執(zhí)行器突然起停而產(chǎn)生地震動會產(chǎn)生一個高的尖峰壓力，從原理上來說這將導(dǎo)致液壓泄漏。,61,學(xué)習(xí)交流PPT,頂升舉例- 比例系統(tǒng)PROPORTIONAL SYSTEM,如果電磁閥和流量控制閥被一個比例閥取代，不僅電梯的速度可以被電子地調(diào)整，而且電梯的起停也可以被控制。,62,學(xué)習(xí)交流PPT,頂升舉例- 比例系統(tǒng)LIFT EXAM

38、PLE - PROPORTIONAL SYSTEM,比例閥能夠足夠慢地打開以提供一個平滑加速度使電梯達(dá)到最大速度。 The proportional valve can be opened sufficiently slowly to provide a smooth acceleration of the lift up to its maximum speed.,63,學(xué)習(xí)交流PPT,頂升舉例- 比例系統(tǒng)LIFT EXAMPLE - PROPORTIONAL SYSTEM,同樣地，減加速度也能夠被控制，使閥芯運(yùn)動回中位的速度變慢。 And likewise the deceleration

39、 can be controlled by slowing down the speed of spool movement back to the centre condition.,64,學(xué)習(xí)交流PPT,time,Distance,運(yùn)動控制 MOTION CONTROL,因此總的來說，比例閥能夠提供全部的運(yùn)動控制包括： In general therefore, proportional valves are capable of providing full motion control in terms of:,65,學(xué)習(xí)交流PPT,time,Acceleration,Distance

40、,MOTION CONTROL,1. A smooth and controlled acceleration of an actuator up to its maximum speed. 一個平滑和受控的加速度，使執(zhí)行器達(dá)到最大速度。,66,學(xué)習(xí)交流PPT,time,Acceleration,Velocity,Distance,MOTION CONTROL,2. Control of the actuator velocity and if necessary maintaining it constant with varying loads. 執(zhí)行器速度的控制，如果必要維持其在變化負(fù)載

41、下的穩(wěn)定。,67,學(xué)習(xí)交流PPT,time,Acceleration,Deceleration,Velocity,Distance,MOTION CONTROL,3. A smooth deceleration with minimal pressure peaks. 一個平滑的帶有最小化壓力峰值的減加速度,68,學(xué)習(xí)交流PPT,time,Position,Acceleration,Deceleration,Velocity,Distance,MOTION CONTROL,4. By using suitable sensing devices, the proportional valve

42、can also be used to control the actuator stopping position to high levels of accuracy. 通過使用合適的傳感裝置，比例閥也可以被用來高精度地控制執(zhí)行器的位置,69,學(xué)習(xí)交流PPT,time,Force,力控制 FORCE CONTROL,比例閥也能夠被用來控制執(zhí)行器力地輸出，通過控制應(yīng)用于執(zhí)行器上地壓強(qiáng)。（例如在壓機(jī)中或注塑機(jī)應(yīng)用）Proportional valves can also be used to control the force output from an actuator (for exam

43、ple in press or plastic injection moulding applications) by controlling the pressure applied to the actuator.,70,學(xué)習(xí)交流PPT,time,Force,FORCE CONTROL,在這樣的實例中，不僅要求控制最大的執(zhí)行器壓力。而且要求控制應(yīng)用中或運(yùn)動中的壓力等級。 In such cases it is often necessary to control not only the maximum actuator pressure but also the rate at whic

44、h the pressure is applied or removed.,71,學(xué)習(xí)交流PPT,time,Force,FORCE CONTROL,In fact the machine cycle may consist of a series of ramps and holding periods all of which can be achieved with just the one proportional valve. 實際上機(jī)器工作周期可能由一系列的斜坡和停止階段組成，所有這些可以由一個比例閥來完成。,72,學(xué)習(xí)交流PPT,time,Force,FORCE CONTROL,A

45、t the end of the machine cycle the rate at which the pressure is reduced is also critical in many processes. 在機(jī)器運(yùn)行周期后段，在很多工序中壓力等級的降低也是要求很嚴(yán)格的。,73,學(xué)習(xí)交流PPT,FORCE CONTROL,Motion and force control can thus be achieved using proportional valves, and in some cases the same valve can be used for both motion

46、 and force control. This is usually referred to as PQ control ie. the control of both pressure (P) and flow (Q). Furthermore, all of these control functions can be achieved using electronic inputs to the valve thus providing a simple interface to the machine controller. 運(yùn)動和力的控制因此能夠通過使用比例閥來完成，同時在某些場合

47、同一個閥能夠同時用于運(yùn)動控制和力控制。這通常被稱為PQ”控制，也就是說同時控制壓力和流量。 此外，所有這些控制功能可以使用輸入到閥的電子輸入信號被完成，只需通過提供的到機(jī)械控制器的簡單接口。,74,學(xué)習(xí)交流PPT,ELECTRONIC CONTROL,電子控制,75,學(xué)習(xí)交流PPT,閥輸入信號 VALVE INPUT SIGNAL,As described earlier, the electrical current to the solenoid of a proportional valve needs to be regulated and not just simply switch

48、ed on or off as is the case with a conventional valve. 作為簡單描述，提供給比例閥電磁鐵的電流需要被調(diào)節(jié)，不象應(yīng)用常規(guī)閥的時僅有開關(guān)通或斷那樣簡單。,76,學(xué)習(xí)交流PPT,閥輸入信號 VALVE INPUT SIGNAL,In theory, this could be achieved by using a dimmer switch type component (ie. a variable resistor). Practical problems such as heat generation and drift however

49、mean that such a device would not normally be used except for the very simplest applications. 在理論上這可以通過使用一個調(diào)光開關(guān)式的元件來完成（例如，一個可變電阻）。實際上由于發(fā)熱和漂移這樣的設(shè)備一般不被使用，除非一些最簡單的應(yīng)用中。,77,學(xué)習(xí)交流PPT,比例閥放大器 PROPORTIONAL VALVE AMPLIFIER,Normally, the current flowing through the proportional solenoid will be controlled by some form of electronic amplifier. The amplifier itself will require a power supply (usually 12 or 24 VDC) and a command input signal. 一般地，通過比例閥電磁鐵地電流由一些形式地電子放大器控制。放大器要求一個電源和一個命令輸入信號。,78,學(xué)習(xí)交流PPT,比例閥放大器 PROPORTION