{"id":59958,"date":"2023-04-21T22:57:23","date_gmt":"2023-04-22T03:57:23","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/how-to-make-a-transducer-pickup\/"},"modified":"2025-01-27T06:09:26","modified_gmt":"2025-01-27T11:09:26","slug":"how-to-make-a-transducer-pickup","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/cs\/how-to-make-a-transducer-pickup\/","title":{"rendered":"DIY sn\u00edma\u010d: Konstrukce piezoelektrick\u00e9ho sn\u00edma\u010de"},"content":{"rendered":"<p>Vytvo\u0159it si vlastn\u00ed sn\u00edma\u010d (pickup) pro p\u0159evod energie, a\u0165 u\u017e mechanick\u00e9, akustick\u00e9, \u010di jin\u00e9, na elektrick\u00fd sign\u00e1l, m\u016f\u017ee b\u00fdt z\u00e1bavn\u00fd a pou\u010dn\u00fd projekt.  Tento \u010dl\u00e1nek se zam\u011b\u0159\u00ed na konstrukci jednoduch\u00e9ho piezoelektrick\u00e9ho sn\u00edma\u010de, kter\u00fd je relativn\u011b snadno vyrobiteln\u00fd a vhodn\u00fd pro r\u016fzn\u00e9 aplikace, od detekce vibrac\u00ed po m\u011b\u0159en\u00ed akustick\u00e9ho tlaku.  Z\u00e1kladn\u00ed princip spo\u010d\u00edv\u00e1 v vyu\u017eit\u00ed piezoelektrick\u00e9ho efektu, kdy se mechanick\u00fd tlak p\u0159em\u011bn\u00ed na elektrick\u00e9 nap\u011bt\u00ed.<\/p>\n<p>V\u00fdb\u011br piezoelektrick\u00fdch element\u016f<\/p>\n<p>Nejd\u016fle\u017eit\u011bj\u0161\u00ed sou\u010d\u00e1st\u00ed sn\u00edma\u010de je piezoelektrick\u00fd element.  K dispozici je \u0161irok\u00e1 \u0161k\u00e1la materi\u00e1l\u016f s r\u016fzn\u00fdmi vlastnostmi.  Pro za\u010d\u00e1te\u010dn\u00edky jsou vhodn\u00e9 disky z keramick\u00e9ho piezoelektrick\u00e9ho materi\u00e1lu, snadno dostupn\u00e9 od r\u016fzn\u00fdch dodavatel\u016f.  D\u016fle\u017eit\u00e9 parametry p\u0159i v\u00fdb\u011bru jsou:<\/p>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Parametr<\/th>\n<th>Jednotka<\/th>\n<th>Typick\u00e1 hodnota<\/th>\n<th>Pozn\u00e1mka<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Kapacita<\/td>\n<td>pF<\/td>\n<td>100 &#8211; 1000<\/td>\n<td>Vliv na citlivost a frekven\u010dn\u00ed odezvu<\/td>\n<\/tr>\n<tr>\n<td>Citlivost<\/td>\n<td>mV\/kN<\/td>\n<td>10 &#8211; 100<\/td>\n<td>Vy\u0161\u0161\u00ed hodnota znamen\u00e1 v\u011bt\u0161\u00ed v\u00fdstupn\u00ed sign\u00e1l<\/td>\n<\/tr>\n<tr>\n<td>Frekven\u010dn\u00ed rozsah<\/td>\n<td>Hz<\/td>\n<td>20 &#8211; 20kHz<\/td>\n<td>Z\u00e1vis\u00ed na geometrii a materi\u00e1lu elementu<\/td>\n<\/tr>\n<tr>\n<td>Rozm\u011bry<\/td>\n<td>mm<\/td>\n<td>10 x 10 &#8211; 20 x 20<\/td>\n<td>Volba dle po\u017eadovan\u00e9 citlivosti a aplikace<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Konstrukce pouzdra a zapojen\u00ed<\/p>\n<p>Piezoelektrick\u00fd element je nutn\u00e9 vhodn\u011b upevnit do pouzdra, kter\u00e9 ho ochr\u00e1n\u00ed p\u0159ed po\u0161kozen\u00edm a z\u00e1rove\u0148 zajist\u00ed efektivn\u00ed p\u0159enos vibrac\u00ed nebo tlaku.  Pouzdro m\u016f\u017ee b\u00fdt vyrobeno z r\u016fzn\u00fdch materi\u00e1l\u016f, nap\u0159\u00edklad z kovu, plastu, nebo d\u0159eva.  D\u016fle\u017eit\u00e9 je, aby bylo pevn\u00e9 a odoln\u00e9, a z\u00e1rove\u0148 aby nep\u0159en\u00e1\u0161elo ne\u017e\u00e1douc\u00ed vibrace.<\/p>\n<p>Zapojen\u00ed je jednoduch\u00e9.  Piezoelektrick\u00fd element m\u00e1 dva v\u00fdvody, kter\u00e9 je nutn\u00e9 p\u0159ipojit k p\u0159edzesilova\u010di.  P\u0159edzesilova\u010d je nezbytn\u00fd pro zes\u00edlen\u00ed slab\u00e9ho sign\u00e1lu z elementu.  M\u016f\u017ee b\u00fdt pou\u017eit opera\u010dn\u00ed zesilova\u010d (op-amp) s vhodnou konfigurac\u00ed.  Je d\u016fle\u017eit\u00e9 zvolit spr\u00e1vn\u00fd typ p\u0159edzesilova\u010de s ohledem na frekven\u010dn\u00ed rozsah a impedanci piezoelektrick\u00e9ho elementu.<\/p>\n<p>Kalibrace a testov\u00e1n\u00ed<\/p>\n<p>Po sestaven\u00ed je nutn\u00e9 sn\u00edma\u010d zkalibrovat.  To znamen\u00e1 ur\u010dit vztah mezi m\u011b\u0159enou veli\u010dinou (nap\u0159. tlakem) a v\u00fdstupn\u00edm elektrick\u00fdm sign\u00e1lem.  Kalibrace se prov\u00e1d\u00ed pomoc\u00ed zn\u00e1m\u00fdch testovac\u00edch sign\u00e1l\u016f.  Nap\u0159\u00edklad pro m\u011b\u0159en\u00ed akustick\u00e9ho tlaku lze pou\u017e\u00edt kalibrovan\u00fd reproduktor s definovanou intenzitou zvuku.  Po kalibraci je mo\u017en\u00e9 sn\u00edma\u010d pou\u017e\u00edvat pro m\u011b\u0159en\u00ed.  Testov\u00e1n\u00ed spo\u010d\u00edv\u00e1 v ov\u011b\u0159en\u00ed spr\u00e1vn\u00e9 funkce sn\u00edma\u010de a jeho citlivosti.<\/p>\n<p>P\u0159\u00edklady aplikac\u00ed<\/p>\n<p>Piezoelektrick\u00e9 sn\u00edma\u010de maj\u00ed \u0161irok\u00e9 spektrum pou\u017eit\u00ed.  Mohou b\u00fdt pou\u017eity pro m\u011b\u0159en\u00ed vibrac\u00ed v stroj\u00edch, pro detekci akustick\u00e9ho tlaku v mikrofonu, nebo pro m\u011b\u0159en\u00ed tlaku v kapalin\u00e1ch.  Nap\u0159\u00edklad mal\u00fd sn\u00edma\u010d m\u016f\u017ee b\u00fdt pou\u017eit pro detekci zvuk\u016f v ultrazvukov\u00fdch za\u0159\u00edzen\u00edch, jako jsou nap\u0159\u00edklad \u010disti\u010dky od firmy Beijing Ultrasonic (pouze v p\u0159\u00edpad\u011b, kdy je to relevantn\u00ed pro kontext).<\/p>\n<p>Z\u00e1v\u011brem lze \u0159\u00edci, \u017ee konstrukce vlastn\u00edho piezoelektrick\u00e9ho sn\u00edma\u010de je relativn\u011b jednoduch\u00fd projekt, kter\u00fd umo\u017e\u0148uje experimentov\u00e1n\u00ed s r\u016fzn\u00fdmi materi\u00e1ly a konfiguracemi.  Spr\u00e1vn\u00fd v\u00fdb\u011br piezoelektrick\u00e9ho elementu a vhodn\u00e1 konstrukce pouzdra jsou kl\u00ed\u010dov\u00e9 pro dosa\u017een\u00ed po\u017eadovan\u00e9 citlivosti a funk\u010dnosti.  S trochou trp\u011blivosti a technick\u00e9ho nad\u0161en\u00ed se tak m\u016f\u017eete dostat k funk\u010dn\u00edmu sn\u00edma\u010di pro r\u016fzn\u00e9 aplikace.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Vytvo\u0159it si vlastn\u00ed sn\u00edma\u010d (pickup) pro p\u0159evod energie, a\u0165 u\u017e mechanick\u00e9, akustick\u00e9, \u010di jin\u00e9, na elektrick\u00fd sign\u00e1l, m\u016f\u017ee b\u00fdt z\u00e1bavn\u00fd a pou\u010dn\u00fd projekt. Tento \u010dl\u00e1nek se zam\u011b\u0159\u00ed na konstrukci jednoduch\u00e9ho piezoelektrick\u00e9ho sn\u00edma\u010de, kter\u00fd je relativn\u011b snadno vyrobiteln\u00fd a vhodn\u00fd pro r\u016fzn\u00e9 aplikace, od detekce vibrac\u00ed po m\u011b\u0159en\u00ed akustick\u00e9ho tlaku. Z\u00e1kladn\u00ed princip spo\u010d\u00edv\u00e1 v vyu\u017eit\u00ed piezoelektrick\u00e9ho<\/p>\n","protected":false},"author":1,"featured_media":26936,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6415],"tags":[],"class_list":["post-59958","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","prodpage-classic"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/59958","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/comments?post=59958"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/59958\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media\/26936"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media?parent=59958"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/categories?post=59958"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/tags?post=59958"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}