【正文】 ses the T shape bolt, Is advantageous for screen board installs the maintenance, Eliminates the U shape bolt to the hollow beam attrition. Principle of work: Two vibrate the electrical machinery the model to be same, May have one kind of bination straightline oscillation. This kind of vibration may cause in the transportation trough body thematerial movement, And has the collision with the screening surface, And has the collision with the screening surface, Thus realization material geometry graduation, Realization screening. The overall plan is: Uses the ordinary screening law, The vibration form for resonates, The path is the translation, Stirs up the strength vibration the way is the inertia type, The vibration isolation way is level of vibration isolations, The vibration isolation spring is the metal screw type vibrationisolation spring。目前全國具有獨(dú)立研究開發(fā)新產(chǎn)品能力的企業(yè)不多，大約有3～4家，每年能創(chuàng)新開發(fā)幾個(gè)新產(chǎn)品，而大多數(shù)企業(yè)仍是生產(chǎn)常規(guī)較為陳舊的產(chǎn)品。二十幾年來，經(jīng)過國內(nèi)外科技工作者孜孜不倦的探索和堅(jiān)持不懈的努力，振動(dòng)理論日趨完善，振動(dòng)規(guī)律逐漸為人們掌握，振動(dòng)也逐漸被應(yīng)用到許多工業(yè)部門用來完成某些工藝過程來提高生產(chǎn)率。 振動(dòng)機(jī)械的特點(diǎn)振動(dòng)機(jī)械同其它類型機(jī)械相比：優(yōu)點(diǎn)是結(jié)構(gòu)簡單、制造容易、重量較輕、成本較低、能耗少、安裝方便、維修容易等。 常見故障及處理措施 篩分時(shí)篩子不下料或下料不暢一是給煤溜槽與篩面之間有落差太小，應(yīng)是其落差在400~500mm之間。壓蓋與軸承外圍之間必須有一定間隙，以保證軸承正常的散熱和一定的軸向串動(dòng)。這樣就可以減少進(jìn)入破碎機(jī)的礦石量，可提高破碎機(jī)的產(chǎn)量。這種振動(dòng)可以使輸送槽體中的物料運(yùn)動(dòng)，并與篩面發(fā)生碰撞，使小于篩孔的物料透過，從而實(shí)現(xiàn)物料的幾何分級(jí)，實(shí)現(xiàn)篩分[10]。 各類篩分方法的比較確定為滿足直線振動(dòng)細(xì)篩的要求和工作特點(diǎn)，我們將振動(dòng)篩分機(jī)所采用的各類篩分方法加以比較，從而確定最佳方案，以達(dá)到設(shè)計(jì)要求。料層厚度與篩長有關(guān)（如圖31所示），篩面越長物料厚度越薄，而且篩分效率也與篩長有關(guān)，篩面越長，則物料的篩分效率越高。（8）給料端厚排料端薄不易分層。概率篩特點(diǎn)：（1）篩面傾角大、物料層薄、物料運(yùn)動(dòng)速度快。這種方法的特點(diǎn)是不管入料中小于篩孔的顆粒所占百分比如何，在篩分過程中，篩上物料厚度保持不變或遞增。 振動(dòng)形式的確定目前，從振動(dòng)機(jī)械動(dòng)力學(xué)方面我們知道，工作頻率和固有頻率之比為Z，一般為210。其運(yùn)動(dòng)軌跡一般為圓形（橢圓形）它主要用于物料的分級(jí)。以下是幾種常見的振動(dòng)方式的比較。但是該振機(jī)振幅因受電源影響不夠穩(wěn)定，而且造價(jià)高，在篩機(jī)中應(yīng)用較小。慣性式激振器通常由主軸、偏心塊、軸承、軸承座組成其按照激振器軸數(shù)又可以分為單軸式、雙軸式、多軸式三種。隔振系統(tǒng)有一次隔振和二次隔振及多次隔振系統(tǒng)等下面通過分析我們進(jìn)行選用。承重管梁與側(cè)板之間使用精制高強(qiáng)度螺栓緊固，這種緊固方式不僅使被緊固件之間利用靜摩擦傳遞振動(dòng)力，而且利用高強(qiáng)度螺桿與鋼板孔的過盈配合，直接傳遞振動(dòng)剪切力，聯(lián)接強(qiáng)度高，使用防松螺母，聯(lián)接可靠不松動(dòng)，將篩箱聯(lián)接成一個(gè)剛性箱體結(jié)構(gòu)，是目前最為有效的聯(lián)接方式。新型縫條篩常用焊條。綜上所述，本設(shè)計(jì)采用木楔條固定壓緊裝置。其缺點(diǎn)是體積較大、容易產(chǎn)生噪音、調(diào)節(jié)其剛度不便、橫向剛度小容易使機(jī)體出現(xiàn)橫向搖晃。采用物料作拋擲運(yùn)動(dòng)狀態(tài)進(jìn)行設(shè)計(jì)，此種運(yùn)動(dòng)形式有如下優(yōu)點(diǎn)：可防止篩孔的堵塞，并能獲得較好的篩分效率和生產(chǎn)率；而且由于物料和工作面接觸時(shí)間短大部分離開工作面，所以工作面的磨損小，并能獲得較高的輸送速度，而且運(yùn)用此種運(yùn)動(dòng)形式可使上下層物料得到翻動(dòng)，使細(xì)粒物的透篩機(jī)會(huì)增多，從而提高工作效率。②際平均速度： V=CmCRCa CωVd (52)Cm—物料性質(zhì)的影響系數(shù)，；CR—料層厚度的影響系數(shù)，；Ca—傾角的影響系數(shù)，；Cω—滑行運(yùn)動(dòng)影響系數(shù)，取1；因此實(shí)際平均速度為：V=。只有這樣中國的篩分技術(shù)才能跟住世界潮流，才能為中國工業(yè)的未來再多做些貢獻(xiàn)，它的發(fā)展不僅僅代表著中國礦山機(jī)械的發(fā)展，它還代表著中國國力的增強(qiáng)，標(biāo)志著一個(gè)國家的基礎(chǔ)工業(yè)的實(shí)力和工業(yè)科技水平。Link mechanismLinkages include garage door mechanisms, car wiper mechanisms, gear shift mechanisms. These type of connections, revolute and prismatic, are called lower pairs. Higher pairs are based on point line or curve interfaces. Examples of lower pairs include hinges rotary bearings, slideways , universal couplings. Examples of higher pairs include cams and gears.Kinematic analysis, a particular given mechanism is investigated based on the mechanism geometry plus factors which identify the motion such as input angular velocity, angular acceleration, etc. Spatial mechanisma are far more plicated to engineer requiring puter synthesis. It is possible to determine this from the number of links and the number and types of joints which connect the links...A free planar link generally has 3 degrees of freedom (x , y, θ ). s law provides a simple test for this conditionGrashof39。These positions are referred to as toggle positions. When using four bar linkages to transfer torque it is generally considered prudent to avoid transmission angles below 450 and 500.In the figure above if link (d) is made the driver the system shown is in a locked position. The velocity of C relative to B is perpedicular to CB and passes through b The diagram below shows how to to construct a vector diagram for the acceleration ponents on a s。 The velocity of P is obtained from the vector diagram by using the relationship bp/bc = BP/BC The velocity vector diagram is easily drawn as shown... Velocity of sliding Block on Rotating LinkConsider a block B sliding on a link rotating about A. The block is instantaneously located at B39。 K3 = ( l 32 l 12 l 22 l 2 4 ) / 2 l 2 l 4 This equation enables the analytic synthesis of a 4 bar linkage. s Equation results from this relationship as K 1 cos θ 2 + K2 cos θ 4 + K 3 = cos ( θ 2 θ 4 )K1 = l1 / l4 The system has no toggle positions and the linkage is a poor design Freudenstein39。These positions allow the 4 bar linkage to be used a clamping tools.The angle β is called the transmission angle.s law states that one of the links (generally the shortest link) will be able to rotate continuously if the following condition is met... b (shortest link ) + c(longest link) a + dFour Inversions of a typical Four Bar LinkageNote: If the above condition was not met then only rocking motion would be possible for any link..Mechanical Advantage of 4 bar linkageThe mechanical advantage of a linkage is the ratio of the output torque exerted by the driven link to the required input torque at the driver link. One link is always fixed so before any joints are attached the number of degrees of freedom of a linkage assembly with n links = DOF = 3 (n1) Connecting two links using a joint which has only on degree of freedom adds two constraints. Connecting two links with a joint which has two degrees of freedom include 1 restraint to the systems. The number of 1 DOF joints = say j 1 and the number of joints with two degrees of freedom = say j 2.. The Mobility of a system is therefore expressed as mobility = m = 3 (n1) 2 j 1 j 2Examples linkages showing the mobility are shown below.. A system with a mobility of 0 is a structure. A system with a mobility of 1 can be fixed in position my positioning only one link. A system with a mobility of 2 requires two links to be positioned to fix the linkage position..This rule is general in nature and there are exceptions but it can provide a very useful initial guide as the the mobility of an arrangement of links...Grashof39。Planar mechanisms ultilising only lower pairs are called planar linkage