振幅測量.rar_vibration_振幅_行业发展研究下载-pudn.com

<html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta charset="utf-8"> <meta name="generator" content="pdf2htmlEX"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <link rel="stylesheet" href="https://static.pudn.com/base/css/base.min.css"> <link rel="stylesheet" href="https://static.pudn.com/base/css/fancy.min.css"> <link rel="stylesheet" href="https://static.pudn.com/prod/directory_preview_static/626af81f7ae5df2aa7edb5f4/raw.css"> <script src="https://static.pudn.com/base/js/compatibility.min.js"></script> <script src="https://static.pudn.com/base/js/pdf2htmlEX.min.js"></script> <script> try{ pdf2htmlEX.defaultViewer = new pdf2htmlEX.Viewer({}); }catch(e){} </script> <title></title> </head> <body> <div id="sidebar" style="display: none"> <div id="outline"> </div> </div> <div id="pf1" class="pf w0 h0" data-page-no="1"><div class="pc pc1 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/626af81f7ae5df2aa7edb5f4/bg1.jpg"><div class="c x0 y1 w2 h2"><div class="t m0 x1 h3 y2 ff1 fs0 fc0 sc0 ls0 ws0">15.3.2 <span class="ff2 sc1">振动幅值的直观测量</span></div><div class="t m0 x1 h3 y3 ff1 fs0 fc0 sc0 ls0 ws0">15.3.2.1 <span class="ff2 sc1">量楔振幅牌</span></div><div class="t m0 x1 h3 y4 ff3 fs1 fc0 sc0 ls0 ws0"> <span class="ff2 fs0">振幅是直线振动设备工作状况的重要表征。用振幅指示牌测量振幅，是直观方法。标牌制</span></div><div class="t m0 x1 h3 y5 ff2 fs0 fc0 sc0 ls0 ws0">作简单，观察方便、易读，测量精度也能满足现场作业的控制要求。</div><div class="t m0 x2 h3 y6 ff2 fs0 fc0 sc0 ls0 ws0">在振动体侧壁上划一条与振动方向垂直的直线（图<span class="_ _0"> </span><span class="ff4">15.3.2-1a</span>）。正弦振动时，这条线顺</div><div class="t m0 x1 h3 y7 ff2 fs0 fc0 sc0 ls0 ws0">振</div><div class="t m0 x3 h3 y8 ff2 fs0 fc0 sc0 ls0 ws0">图<span class="_ _0"> </span><span class="ff4">15.3.2-1</span></div><div class="t m0 x1 h3 y9 ff2 fs0 fc0 sc0 ls0 ws0">动<span class="_ _1"></span>方<span class="_ _1"></span>向<span class="_ _1"></span>来回<span class="_ _1"></span>移<span class="_ _1"></span>动<span class="_ _1"></span>，<span class="_ _1"></span>形<span class="_ _1"></span>成<span class="_ _1"></span>有<span class="_ _1"></span>一定<span class="_ _1"></span>宽<span class="_ _1"></span>度<span class="_ _1"></span>的<span class="_ _1"></span>阴<span class="_ _1"></span>影<span class="_ _1"></span>区<span class="_ _1"></span>。阴<span class="_ _1"></span>影<span class="_ _1"></span>的<span class="_ _1"></span>宽<span class="_ _1"></span>度<span class="_ _1"></span>就<span class="_ _1"></span>是<span class="_ _1"></span>振动<span class="_ _1"></span>体<span class="_ _1"></span>的<span class="_ _1"></span>最<span class="_ _1"></span>大<span class="_ _1"></span>位<span class="_ _1"></span>移<span class="_ _1"></span>距离<span class="_ _1"></span>（<span class="_ _1"></span>图</div><div class="t m0 x1 h3 ya ff4 fs0 fc0 sc0 ls0 ws0">15.3.2-1b<span class="ff2">），即振动体的双振幅。阴影区不易测量，振幅小时肉眼更不易观察，故将直线改</span></div><div class="t m0 x1 h3 yb ff2 fs0 fc0 sc0 ls0 ws0">画为直角三角形，这就是量楔振幅牌，用于测量直线振动振幅。</div><div class="t m0 x2 h3 yc ff2 fs0 fc0 sc0 ls0 ws0">量楔是一个<span class="_ _1"></span>直角三角形，放置在振<span class="_ _1"></span>动体侧壁上，长直角边<span class="_ _1"></span>与振动方向垂直，<span class="_ _1"></span>短直角边平</div><div class="t m0 x1 h3 yd ff2 fs0 fc0 sc0 ls0 ws0">行振动方向（图<span class="_ _0"> </span><span class="ff4">15.3.2-2a</span>）。振动时，直角三角形往复移动，长直角边与斜边形成一个交点</div><div class="t m0 x1 h3 ye ff2 fs0 fc0 sc0 ls0 ws0">（图<span class="_ _0"> </span><span class="ff4">15.3.2-2b</span>），此交点即为双振幅值。</div><div class="t m0 x3 h3 yf ff2 fs0 fc0 sc0 ls0 ws0">图<span class="_ _0"> </span><span class="ff4">15.3.2-2</span></div><div class="t m0 x2 h3 y10 ff2 fs0 fc0 sc0 ls0 ws0">图<span class="_ _0"> </span><span class="ff4">15.3.2-3<span class="_ _2"> </span></span>所示<span class="_ _1"></span>振幅牌<span class="_ _1"></span>，实<span class="_ _1"></span>线为静止<span class="_ _1"></span>状态<span class="_ _1"></span>位置，<span class="_ _1"></span>虚线为<span class="_ _1"></span>上半<span class="_ _1"></span>振动周期<span class="_ _1"></span>的极<span class="_ _1"></span>限位置<span class="_ _1"></span>，点划</div><div class="t m0 x1 h3 y11 ff2 fs0 fc0 sc0 ls0 ws0">线</div><div class="t m0 x3 h3 y12 ff2 fs0 fc0 sc0 ls0 ws0">图<span class="_ _0"> </span><span class="ff4">15.3.2-3</span></div><div class="t m0 x1 h3 y13 ff2 fs0 fc0 sc0 ls0 ws0">为下半振动周期的极限位置。从图中看出，振动时，长直角边和斜边都能达到极限位置<span class="_ _2"> </span><span class="ff4">O<span class="_ _0"> </span></span>处，</div><div class="t m0 x1 h3 y14 ff2 fs0 fc0 sc0 ls0 ws0">且停留时间<span class="_ _1"></span>较长（为其他各点处停<span class="_ _1"></span>留时间的<span class="_ _3"> </span><span class="ff4">2<span class="_ _0"> </span></span>倍）。由<span class="_ _1"></span>于振动频率高，人眼视<span class="_ _1"></span>觉暂留现象，</div><div class="t m0 x1 h3 y15 ff2 fs0 fc0 sc0 ls0 ws0">会看到这两<span class="_ _1"></span>条线相交于一点，并感<span class="_ _1"></span>觉到该点不动。这一交<span class="_ _1"></span>点<span class="_ _3"> </span><span class="ff4">O</span>，位于振动<span class="_ _1"></span>体往复移动最大距</div><div class="t m0 x1 h3 y16 ff2 fs0 fc0 sc0 ls0 ws0">离<span class="_ _2"> </span><span class="ff4">O-O</span></div><div class="t m0 x4 h4 y17 ff4 fs2 fc0 sc0 ls0 ws0">1</div><div class="t m0 x5 h3 y16 ff2 fs0 fc0 sc0 ls0 ws0">和<span class="_ _2"> </span><span class="ff4">O-O</span></div><div class="t m0 x6 h4 y17 ff4 fs2 fc0 sc0 ls0 ws0">2</div><div class="t m0 x7 h3 y16 ff2 fs0 fc0 sc0 ls0 ws0">上<span class="_ _1"></span>，<span class="ff4">O-O</span></div><div class="t m0 x8 h4 y17 ff4 fs2 fc0 sc0 ls0 ws0">1</div><div class="t m0 x9 h3 y16 ff2 fs0 fc0 sc0 ls0 ws0">或<span class="_ _2"> </span><span class="ff4">O-O</span></div><div class="t m0 xa h4 y17 ff4 fs2 fc0 sc0 ls0 ws0">2</div><div class="t m0 xb h3 y16 ff2 fs0 fc0 sc0 ls0 ws0">的<span class="_ _1"></span>长度<span class="_ _1"></span>则<span class="_ _1"></span>反<span class="_ _1"></span>映了<span class="_ _1"></span>振<span class="_ _1"></span>动<span class="_ _1"></span>体的<span class="_ _1"></span>双<span class="_ _1"></span>振<span class="_ _1"></span>幅值<span class="_ _1"></span>。<span class="_ _1"></span>在<span class="_ _1"></span>该点<span class="_ _1"></span>处<span class="_ _1"></span>标<span class="_ _1"></span>注数<span class="_ _1"></span>字<span class="_ _1"></span>，</div><div class="t m0 x1 h3 y18 ff2 fs0 fc0 sc0 ls0 ws0">可方便、清楚地读出双振幅值来。</div><div class="t m0 x2 h3 y19 ff2 fs0 fc0 sc0 ls0 ws0">该相交点的数字如何标定呢？在直角三角形<span class="_ _0"> </span><span class="ff4">ABC<span class="_ _0"> </span></span>中（图<span class="_ _0"> </span><span class="ff4">15.3.2-4</span>）：</div><div class="t m0 x2 h3 y1a ff2 fs0 fc0 sc0 ls0 ws0">（<span class="ff4">a</span>）<span class="_ _4"> </span>长直角边<span class="_ _0"> </span><span class="ff4">AC<span class="_ _0"> </span></span>上的刻度等距分布；</div><div class="t m0 x2 h3 y1b ff2 fs0 fc0 sc0 ls0 ws0">（<span class="ff4">b</span>）<span class="_ _5"> </span><span class="ff4">AC<span class="_ _0"> </span></span>边上的示值范围（被测量范围）等于短直角边<span class="_ _2"> </span><span class="ff4">BC<span class="_ _0"> </span></span>的长度值。即<span class="_ _2"> </span><span class="ff4">AC<span class="_ _0"> </span></span>边上每一</div><div class="t m0 xc h3 y1c ff2 fs0 fc0 sc0 ls0 ws0">刻度的示值，等于从该刻度点到斜边<span class="_ _0"> </span><span class="ff4">AB<span class="_ _0"> </span></span>之间的垂直距离，该示值为被测量的双振幅值；</div><div class="t m0 x2 h3 y1d ff2 fs0 fc0 sc0 ls0 ws0">（<span class="ff4">c</span>）<span class="_ _4"> </span>为<span class="_ _1"></span>使<span class="_ _0"> </span><span class="ff4">AC<span class="_ _2"> </span></span>边<span class="_ _1"></span>上<span class="_ _1"></span>能刻<span class="_ _1"></span>画出<span class="_ _1"></span>更<span class="_ _1"></span>细小<span class="_ _1"></span>的<span class="_ _1"></span>分度<span class="_ _1"></span>值，<span class="_ _1"></span>使<span class="_ _1"></span>被测<span class="_ _1"></span>量<span class="_ _1"></span>的双<span class="_ _1"></span>振幅<span class="_ _1"></span>值<span class="_ _1"></span>更精<span class="_ _1"></span>确<span class="_ _1"></span>，可<span class="_ _1"></span>将<span class="_ _6"> </span><span class="ff4">AC</span></div></div></div><div class="pi" data-data='{"ctm":[1.611850,0.000000,0.000000,1.611850,0.000000,0.000000]}'></div></div> </body> </html>