【正文】 is vibrating screens bine the basic advantages of both circular and linear vibrating screens [9– 10].The long axis of the ellipse determines material delivery and the short axis influences material loosening, to be exact. 3 Dynamics model analysis of vibrating screen with variable elliptical trace We made the exciting force deviate from the center of gravity,to change the motion pattern of the new vibrating stiffness matrix of the vibration isolation 4 spring was not zero under these circumstances and the vibrating system had multiple degrees of transverse wagging was neglected to simplify the motion was considered to be a linear vibration of a rigid beam in the longitudinally symmetrical each point the vibration is a bination of the translation of the center of gravity and the screen pitching about the center of studies neglected the influence of elastic forces in the horizontal and vertical direction on the swing of the vibrating screen [3,11].An accurate dynamic model consisting of three differential equations that include coupling of degrees of freedom in the vertical,horizontal and swing directions is proposed. The mathematical model of the vibrating screen is shown in center of gravity, is taken as the origin of a rectangular coordinate system at static equilibrium, in accordance with rigid motion on the plane [12].Simultaneous differential equations in generalized coordinates using center of gravity coordinates,(x,y),and the swing declination angle, θ ,may be written as 5 where M is the mass of the vibrating screen’s the moment of inertia of M relative to the center of gravity,O。 L1 and L2 the distances between each supporting spring and the center of gravity’s the distance between the rotating center of the eccentric block and the center of gravity。應(yīng)用多自由度振動(dòng)理論 ，對(duì) 振動(dòng)篩的特性進(jìn)行了分析 。振動(dòng)篩 ，如直線振動(dòng)篩、圓振動(dòng) 篩 或橢圓振動(dòng)篩， 都 有一個(gè)簡(jiǎn)單 的 平移運(yùn)動(dòng)。對(duì)于常見(jiàn)的篩網(wǎng)，物料顆粒在入料端廣泛的分布。這導(dǎo)致了物料的垂直深度在入料端厚，而在出料端薄，進(jìn)而影響了篩分效率和處理能力。第一種方法 是材料從多個(gè) 入料 口添加到 振動(dòng)篩 上。 我們?cè)O(shè)計(jì)了一個(gè)基于理想 振動(dòng)篩運(yùn)動(dòng)軌跡的 新的變橢圓 軌跡 振動(dòng)篩用于原煤分類。 在每個(gè)點(diǎn)的振動(dòng)是 平移 重心和 振動(dòng)篩 重心 的結(jié)合。 14 4 變橢圓軌跡振動(dòng)篩的運(yùn)動(dòng)和篩選的效果分析 運(yùn)動(dòng)參數(shù)的分析 運(yùn)用多自由度振動(dòng)理論來(lái)找到一個(gè)強(qiáng)迫振動(dòng)的穩(wěn)定解 [13]，如下： 15 當(dāng) 2 2 2 2 20E S C H ESC H? ? ?， D 點(diǎn)的軌跡是一條直線。只要將偏心塊旋轉(zhuǎn)中心的相對(duì)位置和重心適當(dāng)調(diào)整，就可以獲得振動(dòng)篩上的變橢圓軌跡運(yùn)動(dòng)。 2)振動(dòng)篩的運(yùn)動(dòng)分析理論是研究各種不同的參數(shù) 是 如何 影響 振動(dòng)篩 的動(dòng)作 的。這是一個(gè)需要進(jìn)一步研究的點(diǎn)。這些參數(shù)與篩選效率相關(guān)。圖 3水平和垂直方向的相位差和擺角的振幅一樣。39。重心 被作為一個(gè)靜力平衡直角坐標(biāo)系的原點(diǎn) ，與平面上的剛體運(yùn)動(dòng)相一致 [12]。 3 變橢圓軌跡振動(dòng)篩的動(dòng)力學(xué)模型分析 我們使激振力偏離中心，來(lái)改變新的振動(dòng)篩的運(yùn)動(dòng)模式。 新的 振動(dòng)篩的 表面運(yùn)動(dòng)使材料保持相同 ，或者增加厚度。振動(dòng)篩 有一個(gè)適當(dāng)?shù)膾仈S指數(shù)和高一點(diǎn)材料 傳遞 速度的中間 部分 。細(xì)質(zhì)級(jí)材料的減少， 導(dǎo)致粒子的比例接近或大于網(wǎng)格增加 的大小 。振動(dòng)篩的不同部分有著不同的橢 圓運(yùn)動(dòng)軌跡，由此產(chǎn)生的運(yùn)動(dòng)與理想的運(yùn)動(dòng)軌跡相吻合。 結(jié)果顯示，新設(shè)計(jì)的振動(dòng)篩 的軌跡遵循 理想的篩選 運(yùn)動(dòng) 。Technology,2021,16(4):399– 403. [7]Zhang E ,Crushing and Dewatering Equipments. Beijing: China Coal Industry Publishing House,1991. [8] Khoury D Cleaning Technology .USA:Noyes Data Corporation,1981. [9]Shang N X,Na J elliptical vibration screen. Miningamp。 α the installation angle。screening process with constant bed thickness。x and y the displacements in the x and y0directionas。 and,βthe included angle between the l and x directions. The damping force is rather small and can be neglected. Then Eq. (1) can be simplified to Eq.(2). 4 Motion and screening effect analysis of a vibrating screen with variable elliptical trace Analysis of the motion parameters Multiple degreeoffreedom vibration theory was used to find a stable solution for the forced vibration [13],as follows: 6