{"id":100034,"date":"2026-02-15T20:07:32","date_gmt":"2026-02-15T20:07:32","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100034"},"modified":"2026-07-11T20:31:13","modified_gmt":"2026-07-11T20:31:13","slug":"belt-drive-calculator","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/lv\/calculators\/belt-drive-calculator\/","title":{"rendered":"Atv\u0113rtas siksnas p\u0101rvada \u0123eometrijas kalkulators | Prec\u012bzs garums un starpass att\u0101lums"},"content":{"rendered":"\r\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Open Belt Geometry Calculator\",\"description\":\"Calculate exact geometric pitch\/datum belt length from two pulley diameters and center distance, or solve center distance numerically from belt length.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/belt-drive-calculator\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any (Web Browser)\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"dateModified\":\"2026-07-11\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\r\n\r\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"Is the common 2C formula exact?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. L\u22482C+\u03c0(D1+D2)\/2+(D2\u2212D1)^2\/(4C) is a common approximation. This page uses exact tangent geometry for an open two-pulley drive.\"}},{\"@type\":\"Question\",\"name\":\"How is center distance found from belt length?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The exact length equation is monotonic for valid open-belt geometry, so the calculator solves it numerically by bisection rather than presenting the closed-form inverse of an approximation as exact.\"}},{\"@type\":\"Question\",\"name\":\"Which diameter and length definitions apply?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Use a matching pitch\/datum system from the belt manufacturer. Synchronous-belt pitch diameter and V-belt datum\/effective diameter are not pulley outside diameter.\"}},{\"@type\":\"Question\",\"name\":\"Is 120 degrees a universal minimum wrap angle?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. Required wrap or teeth in mesh depends on belt family, profile, load and manufacturer rating procedure. This tool reports geometry without automatic acceptance.\"}},{\"@type\":\"Question\",\"name\":\"Are speed and ratio results corrected for slip?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. They use ideal no-slip pitch-line kinematics. Use measured speeds or a validated product-specific model when slip or creep matters.\"}}]}<\/script>\r\n\r\n<script type=\"application\/ld+json\">\r\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[\r\n{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},\r\n{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},\r\n{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Belt Drive Calculator\",\"item\":\"https:\/\/vibromera.eu\/calculators\/belt-drive-calculator\/\"}\r\n]}\r\n<\/script>\r\n\r\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\r\n\r\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\r\n\r\n<link 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var(--vc-border-light);border-radius:6px;overflow:hidden}.vc-faq-q{width:100%;display:flex;align-items:center;justify-content:space-between;gap:12px;padding:14px 16px;border:none;background:var(--vc-surface-alt);cursor:pointer;font-family:var(--vc-font);font-size:15px;font-weight:600;color:var(--vc-ink);text-align:left;transition:background .15s}.vc-faq-q:hover{background:#ede9e3}.vc-faq-chevron{width:16px;height:16px;color:var(--vc-ink-muted);flex-shrink:0;transition:transform .25s}.vc-faq-item.vc-open .vc-faq-chevron{transform:rotate(180deg)}.vc-faq-a{max-height:0;overflow:hidden;transition:max-height .35s}.vc-faq-item.vc-open .vc-faq-a{max-height:1200px}.vc-faq-a-inner{padding:14px 16px;border-top:1px solid var(--vc-border-light);font-size:14px;color:var(--vc-ink-secondary)}.vc-faq-a-inner p{margin:0 0 8px}.vc-faq-a-inner p:last-child{margin-bottom:0}.vc-faq-a-inner ul{margin:4px 0 8px 16px;padding:0}.vc-faq-a-inner li{margin-bottom:3px}\r\n.vc-related{display:flex;flex-wrap:wrap;gap:10px;margin-top:16px}.vc-related-link{display:inline-block;padding:8px 16px;font-family:var(--vc-font);font-size:13px;font-weight:600;background:var(--vc-surface-alt);color:var(--vc-ink-secondary);border:1px solid var(--vc-border);border-radius:var(--vc-radius);text-decoration:none;transition:all .15s}.vc-related-link:hover{border-color:var(--vc-accent);color:var(--vc-accent);background:var(--vc-accent-light)}\r\n.vc-promo{margin-top:24px;padding:20px;background:linear-gradient(135deg,var(--vc-accent-light),var(--vc-surface));border:1px solid var(--vc-border);border-radius:var(--vc-radius-lg);display:flex;align-items:center;gap:16px}.vc-promo-text{flex:1;font-size:14px;color:var(--vc-ink-secondary)}.vc-promo-text strong{color:var(--vc-ink)}.vc-promo-link{padding:8px 20px;font-size:13px;font-weight:700;color:#fff;background:var(--vc-accent);border-radius:var(--vc-radius);text-decoration:none;white-space:nowrap;transition:background .15s}.vc-promo-link:hover{background:var(--vc-accent-hover)}\r\n.vc-footer{text-align:center;padding:32px 16px;font-size:13px;color:var(--vc-ink-muted)}.vc-footer a{color:var(--vc-accent);text-decoration:none}.vc-footer a:hover{text-decoration:underline}.vc-footer-links{margin-top:8px;font-size:12px}.vc-footer-links a{margin:0 8px}\r\n@media print{.vc-section-body{max-height:none!important}.vc-faq-a{max-height:none!important}.vc-results{max-height:none!important;padding:24px!important}.vc-copy-btn,.vc-section-chevron,.vc-faq-chevron,.vc-presets,.vc-promo{display:none!important}}\r\n<\/style>\r\n\r\n<div class=\"vc-calculator\" id=\"vc-belt-drive\">\r\n\r\n<header class=\"vc-header\"><p class=\"vc-header-eyebrow\">Free Engineering Tool #087<\/p><h1 class=\"vc-header-title\">Open Belt Geometry Calculator<\/h1><p class=\"vc-header-subtitle\">Calculate exact open-belt tangent geometry from matching pitch\/datum dimensions, or solve center distance numerically from a known belt length.<\/p><div class=\"vc-badges\"><span class=\"vc-badge\">Exact Tangent Geometry<\/span><span class=\"vc-badge\">Numerical Inverse<\/span><span class=\"vc-badge\">No-Slip Reference<\/span><\/div><\/header>\r\n\r\n<div class=\"vc-card\">\r\n    <div class=\"vc-unit-bar\">\r\n        <button type=\"button\" class=\"vc-unit-btn vc-active\" data-mode=\"length\">Belt Length from C<\/button>\r\n        <button type=\"button\" class=\"vc-unit-btn\" data-mode=\"center\">Center Distance from L<\/button>\r\n    <\/div>\r\n\r\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\"><div class=\"vc-form-grid\">\r\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-d1\">Driver pitch\/datum diameter D\u2081 <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"text\" id=\"vc-d1\" inputmode=\"decimal\" value=\"100\"><\/div>\r\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-d2\">Driven pitch\/datum diameter D\u2082 <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"text\" id=\"vc-d2\" inputmode=\"decimal\" value=\"300\"><\/div>\r\n<div class=\"vc-field\" id=\"vc-field-c\"><label class=\"vc-label\" for=\"vc-center\">Center distance C <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"text\" id=\"vc-center\" inputmode=\"decimal\" value=\"500\"><\/div>\r\n<div class=\"vc-field\" id=\"vc-field-l\" style=\"display:none\"><label class=\"vc-label\" for=\"vc-beltlen\">Pitch\/datum belt length L <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"text\" id=\"vc-beltlen\" inputmode=\"decimal\" value=\"1648.3\"><\/div>\r\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-n1\">Driver speed n\u2081 <span class=\"vc-label-hint\">(r\/min; optional)<\/span><\/label><input class=\"vc-input\" type=\"text\" id=\"vc-n1\" inputmode=\"decimal\" value=\"1500\"><\/div>\r\n<\/div><div class=\"vc-warning-box\"><p><strong>Scope:<\/strong> uncrossed open drive with two circular pitch\/datum pulleys and straight tangent spans. Use one manufacturer-consistent diameter\/length system. Flanged\/idler\/multi-pulley paths, belt thickness corrections, installation allowance, elasticity, creep and slip are excluded.<\/p><\/div><\/form>\r\n\r\n    <div class=\"vc-results\" id=\"vc-results\"><div class=\"vc-results-head\"><h2 class=\"vc-results-title\">Geometric Results<\/h2><button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\">Copy<\/button><\/div><div class=\"vc-result-grid\">\r\n<div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\" id=\"vc-r-main-label\">Exact Belt Length<\/div><div class=\"vc-rcard-value\" id=\"vc-r-main\">\u2014<\/div><\/div>\r\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Small-pulley wrap angle<\/div><div class=\"vc-rcard-value\" id=\"vc-r-wrap-small\">\u2014<\/div><\/div>\r\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Large-pulley wrap angle<\/div><div class=\"vc-rcard-value\" id=\"vc-r-wrap-large\">\u2014<\/div><\/div>\r\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Straight tangent span<\/div><div class=\"vc-rcard-value\" id=\"vc-r-span\">\u2014<\/div><\/div>\r\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Directed ratio n\u2082\/n\u2081 = D\u2081\/D\u2082<\/div><div class=\"vc-rcard-value\" id=\"vc-r-ratio\">\u2014<\/div><\/div>\r\n<div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Pitch-line speed \/ driven speed<\/div><div class=\"vc-rcard-value\" id=\"vc-r-speed\">\u2014<\/div><\/div><\/div>\r\n<p style=\"font-size:12px;color:var(--vc-ink-muted)\">Wrap is reported without automatic pass\/fail; consult the exact belt rating procedure for minimum wrap or teeth in mesh.<\/p><\/div><\/div>\r\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udcd8<\/span><span class=\"vc-section-title\">Exact Geometry, Limits &amp; Sources<\/span><\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner vc-theory\">\r\n<h3>Open-belt tangent geometry<\/h3><div class=\"vc-formula-box\">\u03b8 = asin((D<sub>L<\/sub>\u2212D<sub>S<\/sub>)\/(2C))<\/div><div class=\"vc-formula-box\">L = 2\u221a(C\u00b2\u2212((D<sub>L<\/sub>\u2212D<sub>S<\/sub>)\/2)\u00b2) + \u03c0(D<sub>L<\/sub>+D<sub>S<\/sub>)\/2 + (D<sub>L<\/sub>\u2212D<sub>S<\/sub>)\u03b8<\/div><div class=\"vc-formula-box\">\u03b1<sub>S<\/sub>=\u03c0\u22122\u03b8; &nbsp; \u03b1<sub>L<\/sub>=\u03c0+2\u03b8<\/div>\r\n<p>The familiar expression 2C+\u03c0(D\u2081+D\u2082)\/2+(D\u2082\u2212D\u2081)\u00b2\/(4C) is an approximation obtained from the exact geometry. Its closed-form inverse is therefore also approximate. This calculator solves the exact monotonic equation by bisection.<\/p>\r\n<p>Gates publishes exact pitch-length geometry for belt-drive design and separately labels an approximate center-distance relation. Source: <a href=\"https:\/\/www.gates.com\/content\/dam\/documents-library\/catalogs\/light-power-and-precision-manual.pdf\" target=\"_blank\" rel=\"noopener\">Gates Light Power and Precision Manual<\/a>. Diameter terminology is also cross-checked against <a href=\"https:\/\/www.gates.com\/content\/dam\/documents-library\/catalogs\/industrial-timing-belt-design-manual-kr.pdf\" target=\"_blank\" rel=\"noopener\">Gates timing-belt design<\/a> and <a href=\"https:\/\/www.optibelt.com\/fileadmin\/pdf\/produkte\/keilriemen\/Optibelt-TM-v-belt-drives.pdf\" target=\"_blank\" rel=\"noopener\">Optibelt V-belt datum system<\/a>.<\/p>\r\n<div class=\"vc-info-box\"><p><strong>Selection boundary:<\/strong> exact geometric length is not automatically a purchasable belt designation. Select a standard product length, then solve the resulting center distance and verify wrap\/teeth in mesh, tension, power rating and adjustment allowance using that product&#8217;s method.<\/p><\/div>\r\n<\/div><\/div><\/div><div class=\"vc-section\" id=\"vc-sec-related\">\r\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udd17<\/span><span class=\"vc-section-title\">Related Calculators<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\r\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\">\r\n        <a class=\"vc-related-link\" href=\"\/calculators\/v-belt-calculator\/\">V-Belt Selection Calculator<\/a>\r\n        <a class=\"vc-related-link\" href=\"\/calculators\/timing-belt-calculator\/\">Timing Belt Calculator<\/a>\r\n        <a class=\"vc-related-link\" href=\"\/calculators\/gear-ratio-calculator\/\">Gear Ratio Calculator<\/a>\r\n        <a class=\"vc-related-link\" href=\"\/calculators\/chain-drive-calculator\/\">Chain Drive Calculator<\/a>\r\n    <\/div><\/div><\/div>\r\n<\/div>\r\n\r\n<div class=\"vc-section\" id=\"vc-sec-faq\">\r\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\u2753<\/span><span class=\"vc-section-title\">Frequently Asked Questions<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\r\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div>\r\n<\/div>\r\n\r\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional field balancing instruments and software. Used in 50+ countries.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\r\n<footer class=\"vc-footer\"><p>\u00a9 2024\u20132026 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p><p style=\"font-size:12px;margin-top:4px;\">Exact open two-pulley geometry; general engineering reference, not an ISO formula. Scientific review: July 2026<\/p><\/footer>\r\n\r\n<\/div>\r\n\r\n<script>(function(){'use strict';var SLUG='belt-drive-calculator',mode='length';function $(id){return document.getElementById(id)}function parseN(raw,optional){var s=String(raw).trim().replace(\/\\s+\/g,'');if(optional&&s==='')return null;if(!\/^[+]?(?:\\d+(?:[.,]\\d*)?|[.,]\\d+)$\/.test(s))return NaN;return Number(s.replace(',','.'))}function fmt(n,d){return n.toFixed(d).replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,'')}\r\nfunction exactLength(Ds,Dl,C){var h=(Dl-Ds)\/2;if(!(C>h*(1+1e-12)))return NaN;var th=Math.asin(h\/C);return 2*Math.sqrt(C*C-h*h)+Math.PI*(Dl+Ds)\/2+(Dl-Ds)*th}function solveCenter(Ds,Dl,L){if(!(L>Math.PI*Dl*(1+1e-12)))return NaN;var h=(Dl-Ds)\/2,lo=h*(1+1e-11),hi=Math.max(L\/2,L);while(exactLength(Ds,Dl,hi)<L)hi*=2;for(var i=0;i<100;i++){var m=(lo+hi)\/2;if(exactLength(Ds,Dl,m)<L)lo=m;else hi=m}return(lo+hi)\/2}\r\nfunction calculate(){var D1=parseN($('vc-d1').value),D2=parseN($('vc-d2').value),n1=parseN($('vc-n1').value,true);if(!isFinite(D1)||D1<=0||!isFinite(D2)||D2<=0||(n1!==null&&(!isFinite(n1)||n1<=0))){$('vc-results').classList.remove('vc-visible');return}var Ds=Math.min(D1,D2),Dl=Math.max(D1,D2),C,L;if(mode==='length'){C=parseN($('vc-center').value);if(!isFinite(C)||C<=((Dl-Ds)\/2)*(1+1e-12)){$('vc-results').classList.remove('vc-visible');return}L=exactLength(Ds,Dl,C);$('vc-r-main-label').textContent='Exact Belt Length';$('vc-r-main').innerHTML=fmt(L,4)+' <span class=\"vc-rcard-unit\">mm<\/span>'}else{L=parseN($('vc-beltlen').value);if(!isFinite(L)){ $('vc-results').classList.remove('vc-visible');return}C=solveCenter(Ds,Dl,L);if(!isFinite(C)){$('vc-results').classList.remove('vc-visible');return}$('vc-r-main-label').textContent='Solved Center Distance';$('vc-r-main').innerHTML=fmt(C,4)+' <span class=\"vc-rcard-unit\">mm<\/span>'}var h=(Dl-Ds)\/2,th=Math.asin(h\/C),span=Math.sqrt(C*C-h*h),small=(Math.PI-2*th)*180\/Math.PI,large=(Math.PI+2*th)*180\/Math.PI;$('vc-r-wrap-small').innerHTML=fmt(small,4)+'\u00b0';$('vc-r-wrap-large').innerHTML=fmt(large,4)+'\u00b0';$('vc-r-span').innerHTML=fmt(span,4)+' <span class=\"vc-rcard-unit\">mm each<\/span>';$('vc-r-ratio').textContent=fmt(D1\/D2,8);if(n1!==null){var v=Math.PI*D1*n1\/60000,n2=n1*D1\/D2;$('vc-r-speed').innerHTML=fmt(v,4)+' <span class=\"vc-rcard-unit\">m\/s; '+fmt(n2,2)+' r\/min<\/span>'}else $('vc-r-speed').textContent='\u2014';$('vc-results').classList.add('vc-visible');var u=new URL(location);u.searchParams.set('mode',mode);u.searchParams.set('d1',D1);u.searchParams.set('d2',D2);if(mode==='length'){u.searchParams.set('center',C);u.searchParams.delete('beltlen')}else{u.searchParams.set('beltlen',L);u.searchParams.delete('center')}if(n1===null)u.searchParams.delete('n1');else u.searchParams.set('n1',n1);history.replaceState(null,'',u.toString());saveHistory({mode:mode,d1:D1,d2:D2,C:C,L:L,n1:n1,_summary:(mode==='length'?'L '+fmt(L,2):'C '+fmt(C,2))+' mm'})}\r\ndocument.querySelectorAll('.vc-unit-btn').forEach(function(b){b.addEventListener('click',function(){mode=this.getAttribute('data-mode');document.querySelectorAll('.vc-unit-btn').forEach(function(x){x.classList.toggle('vc-active',x===b)});$('vc-field-c').style.display=mode==='length'?'':'none';$('vc-field-l').style.display=mode==='center'?'':'none';calculate()})});$('vc-form').addEventListener('input',calculate);$('vc-copy-btn').addEventListener('click',function(){var t=$('vc-r-main-label').textContent+': '+$('vc-r-main').textContent+'\\nSmall wrap: '+$('vc-r-wrap-small').textContent+'\\nLarge wrap: '+$('vc-r-wrap-large').textContent;if(navigator.clipboard)navigator.clipboard.writeText(t)});document.querySelectorAll('.vc-section-toggle').forEach(function(b){b.addEventListener('click',function(){this.closest('.vc-section').classList.toggle('vc-open')})});var faqData=[{q:'Is the common 2C formula exact?',a:'<p>No. It is an approximation; this page uses exact tangent geometry.<\/p>'},{q:'How is center distance inverted?',a:'<p>By numerical bisection of the exact monotonic length equation.<\/p>'},{q:'Which diameter applies?',a:'<p>Use matching pitch\/datum diameters and belt length, not outside diameter.<\/p>'},{q:'Is 120\u00b0 universally acceptable?',a:'<p>No. Verify wrap or teeth in mesh using the exact product rating method.<\/p>'},{q:'Does speed include slip?',a:'<p>No. Speed outputs use ideal no-slip kinematics.<\/p>'}];var fl=$('vc-faq-list');faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\">'+f.q+'<\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>'});fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open')});function saveHistory(e){var k='vc_history_'+SLUG,a=[];try{a=JSON.parse(localStorage.getItem(k))||[]}catch(x){}e._ts=new Date().toISOString();a.unshift(e);try{localStorage.setItem(k,JSON.stringify(a.slice(0,10)))}catch(x){}}function load(){var p=new URLSearchParams(location.search);['d1','d2','center','beltlen','n1'].forEach(function(k){if(p.has(k)&&$('vc-'+k))$('vc-'+k).value=p.get(k)});if(p.get('mode')==='center'){mode='center';document.querySelectorAll('.vc-unit-btn').forEach(function(b){b.classList.toggle('vc-active',b.getAttribute('data-mode')==='center')});$('vc-field-c').style.display='none';$('vc-field-l').style.display=''}}function init(){load();calculate()}if(document.readyState==='loading')document.addEventListener('DOMContentLoaded',init);else init()})();<\/script>\r\n","protected":false},"excerpt":{"rendered":"<p>Exact open two-pulley pitch\/datum geometry with numerical center-distance inversion, wrap angles and no-slip speed reference.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100034","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/calculator\/100034","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":3,"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/calculator\/100034\/revisions"}],"predecessor-version":[{"id":102322,"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/calculator\/100034\/revisions\/102322"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/media?parent=100034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/categories?post=100034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/lv\/wp-json\/wp\/v2\/tags?post=100034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}