{"id":5703,"date":"2025-07-23T11:02:37","date_gmt":"2025-07-23T05:32:37","guid":{"rendered":"https:\/\/study.madeeasy.in\/?p=5703"},"modified":"2025-07-23T11:02:37","modified_gmt":"2025-07-23T05:32:37","slug":"pantograph-mechanism","status":"publish","type":"post","link":"https:\/\/www.madeeasy.in\/study\/me\/theory-of-machines\/pantograph-mechanism","title":{"rendered":"Pantograph"},"content":{"rendered":"<h2>PANTOGRAPH<\/h2>\n<p style=\"text-align: justify;\">A pantograph is a four-bar linkage used to produce paths exactly similar to the ones traced out by a point on the linkage. The paths so produced are, usually, on an enlarged or reduced scale and may be straight or curved ones.<\/p>\n<p style=\"text-align: justify;\">A pantograph is a geometrical instrument used in drawing offices for reproducing given geometrical figures or plane areas of any shape on an enlarged or reduced scale. It is also used for guiding cutting tools. Its mechanism is utilized as an indicator rig for reproducing the displacement of the crosshead of a reciprocating engine, which, in effect, gives the position of displacement.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-5704 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2025\/07\/pantograph.jpg\" alt=\"Pantograph\" width=\"551\" height=\"182\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2025\/07\/pantograph.jpg 551w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2025\/07\/pantograph-300x99.jpg 300w\" sizes=\"auto, (max-width: 551px) 100vw, 551px\" \/><\/p>\n<p style=\"text-align: justify;\">Fig. (a) shows the line diagram of a pantograph in which AB = CD, BC = AD and ABCD is located\/jointed in such a way that it remains in a parallelogram position. OQP is a straight line and P describes a path similar to that described by Q.<\/p>\n<p style=\"text-align: justify;\"><strong> Proof:<\/strong> To prove that the path described by P is similar to that described by Q, let us consider similar triangles \u0394OAQ and \u0394OBP in which \u2220BOP is common.<\/p>\n<p>As AQ || BP, \u2220OQA = \u2220OPB<\/p>\n<p>So, OA\/OB = OQ\/OP = AQ\/BP &#8230;(3.1)<\/p>\n<p>All links are rigid, form the displaced position shown in Fig. (b)<\/p>\n<p style=\"text-align: center;\">B<sub>1<\/sub>O = BO<\/p>\n<p style=\"text-align: center;\">D<sub>1<\/sub>A<sub>1<\/sub> = DA<\/p>\n<p style=\"text-align: center;\">A<sub>1<\/sub>O = AO<\/p>\n<p style=\"text-align: center;\">and P<sub>1<\/sub>B<sub>1<\/sub> = PB<\/p>\n<p style=\"text-align: center;\">B<sub>1<\/sub>A<sub>1<\/sub> = BA<\/p>\n<p style=\"text-align: center;\">A<sub>1<\/sub>Q<sub>1<\/sub> = AQ<\/p>\n<p style=\"text-align: center;\">OA<sub>1<\/sub>\/OB<sub>1<\/sub> = A<sub>1<\/sub>Q<sub>1<\/sub>\/B<sub>1<\/sub>P<sub>1<\/sub><\/p>\n<p style=\"text-align: center;\">As A<sub>1<\/sub> B<sub>1<\/sub> C<sub>1<\/sub> D<sub>1<\/sub> is also a parallelogram in displaced position,<\/p>\n<p style=\"text-align: center;\">A<sub>1<\/sub>D<sub>1<\/sub> || B<sub>1<\/sub>C<sub>1<\/sub> i.e. A<sub>1<\/sub>Q<sub>1<\/sub> || B<sub>1<\/sub>P<sub>1<\/sub><\/p>\n<p style=\"text-align: center;\">OQ1P1 is again a straight line so that \u0394OA<sub>1<\/sub>Q<sub>1<\/sub> and \u0394OB<sub>1<\/sub>P<sub>1<\/sub> is similar.<\/p>\n<p style=\"text-align: center;\">OA<sub>1<\/sub>\/OB<sub>1<\/sub> = OQ<sub>1<\/sub>\/OP<sub>1<\/sub> &#8230;(3.2)<\/p>\n<p style=\"text-align: center;\">From Equation 3.1 and 3.2, we get<\/p>\n<p style=\"text-align: center;\">OQ\/OP = OQ<sub>1<\/sub>\/OP<sub>1<\/sub> because OA = OA<sub>1<\/sub> and OB = OB<sub>1<\/sub><\/p>\n<p>Hence, OQ<sub>1<\/sub> is similar to OP<sub>1<\/sub> or they are parallel. Thus, path traced by P is similar to that of Q.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>PANTOGRAPH A pantograph is a four-bar linkage used to produce paths exactly similar to the ones traced out by a<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[287,10],"tags":[],"class_list":["post-5703","post","type-post","status-publish","format-standard","hentry","category-theory-of-machines","category-me"],"_links":{"self":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts\/5703","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/comments?post=5703"}],"version-history":[{"count":0,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts\/5703\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/media?parent=5703"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/categories?post=5703"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/tags?post=5703"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}