--- /dev/null
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+<title>USB desk fan modification</title>
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+<meta name="author" content="Svjatoslav Agejenko">
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+<div id="content" class="container">
+<div class="row"><div class="col-md-9"><h1 class="title">USB desk fan modification</h1>
+
+<div id="outline-container-sec-1" class="outline-2">
+<h2 id="sec-1"><span class="section-number-2">1</span> General</h2>
+<div class="outline-text-2" id="text-1">
+<ul class="org-ul">
+<li>DISCLAIMER: I DO ELECTRONICS AND 3D DESIGN SOLELY AS A HOBBY. THERE
+COULD BE ERRORS THAT CAN RESULT IN ALL KINDS OF DAMAGE. USE THESE
+DESIGNS AT YOUR OWN RISK.
+</li>
+
+<li>This design is released under Creative Commons Zero (CC0) license.
+</li>
+
+<li>Authors:
+<ul class="org-ul">
+<li>Svjatoslav Agejenko
+<ul class="org-ul">
+<li>Homepage: <a href="https://svjatoslav.eu">https://svjatoslav.eu</a>
+</li>
+<li>Email: <a href="mailto://svjatoslav@svjatoslav.eu">svjatoslav@svjatoslav.eu</a>
+</li>
+</ul>
+</li>
+
+<li>Valeria Agejenko
+</li>
+</ul>
+</li>
+
+<li>See also:
+<ul class="org-ul">
+<li><a href="../../index.html">Other physical projects in this repository</a>
+</li>
+<li><a href="https://www.svjatoslav.eu/projects/">Other projects hosted at svjatoslav.eu</a>
+</li>
+</ul>
+</li>
+</ul>
+</div>
+</div>
+
+<div id="outline-container-sec-2" class="outline-2">
+<h2 id="sec-2"><span class="section-number-2">2</span> Project description</h2>
+<div class="outline-text-2" id="text-2">
+<p>
+End-result looks like this:
+</p>
+
+
+<figure>
+<p><img src="make.png" class="img-responsive" alt="make.png">
+</p>
+</figure>
+
+<p>
+It all started with couple of cheap USB desk fans that were a bit too
+noisy:
+</p>
+
+
+<figure>
+<p><img src="mini%20fan.png" class="img-responsive" alt="mini%20fan.png">
+</p>
+</figure>
+
+<p>
+Idea is to add DC-DC step-down converter to reduce motor voltage to
+make it quieter (<a href="https://www.amazon.de/gp/product/B07K3W78SQ/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1">Purchased form here</a>). And since I already have this
+USB powered thing on my desk, why not to share this power to allow
+charging of various other USB powered devices.
+</p>
+
+<p>
+I ended up with this schematic:
+<img src="schematic.png" class="img-responsive" alt="schematic.png">
+</p>
+
+<p>
+USB power of 5 volts that enters the system via DC jack is distributed
+to two USB-A connectors on the front panel. Note: USB data is not
+connected. Therefore this hub is for power sharing only.
+</p>
+
+<p>
+DC-DC fly-back converter could introduce voltage ripple in the
+system. To smooth it out, there is capacitor (C1) and inductor (L1).
+</p>
+
+<p>
+Step-down voltage converter has adjustable output voltage. So after
+assembling, it can be tuned with screw-driver to reach desired
+noise/airflow tradeoff.
+</p>
+
+<p>
+From original fan I only kept the engine and blades. Engine is
+attached with screws to following back-plate:
+</p>
+
+
+<figure>
+<p><img src="fan%20housing%20-%20fan%20mount.png" class="img-responsive" alt="fan%20housing%20-%20fan%20mount.png">
+</p>
+</figure>
+
+<p>
+And result is encased into pipelike case:
+</p>
+
+
+<figure>
+<p><img src="fan%20housing%20-%20cover%20assembly.png" class="img-responsive" alt="fan%20housing%20-%20cover%20assembly.png">
+</p>
+</figure>
+
+
+<p>
+Download:
+</p>
+<ul class="org-ul">
+<li>STL: <a href="fan%20housing%20-%20fan%20mount.stl">fan mount back plate</a>
+</li>
+<li>STL: <a href="fan%20housing%20-%20cover.stl">pipe-like case</a>
+</li>
+<li><a href="fan%20housing.FCStd">FreeCAD project</a>
+</li>
+</ul>
+
+<p>
+Fan enclosure attaches to the rectangular body below using following
+connector (glued to the fan housing):
+</p>
+
+
+<figure>
+<p><img src="fan%20housing%20connector.png" class="img-responsive" alt="fan%20housing%20connector.png">
+</p>
+</figure>
+
+<p>
+Download:
+</p>
+<ul class="org-ul">
+<li><a href="fan%20housing%20connector.stl">STL file</a>
+</li>
+<li><a href="fan%20housing%20connector.FCStd">FreeCAD project</a>
+</li>
+</ul>
+
+<p>
+Bottom part to house 2 PCBs, on/off button and DC connector:
+<img src="bottom%20stand%20body.png" class="img-responsive" alt="bottom%20stand%20body.png">
+</p>
+
+<p>
+Component attachment:
+<img src="make,%202.png" class="img-responsive" alt="make,%202.png">
+</p>
+
+<p>
+And is closed by cover:
+<img src="bottom%20stand%20cover%20assembly.png" class="img-responsive" alt="bottom%20stand%20cover%20assembly.png">
+</p>
+
+<p>
+Download:
+</p>
+<ul class="org-ul">
+<li>STL: <a href="bottom%20stand%20body.stl">bottom stand body</a>
+</li>
+<li>STL: <a href="bottom%20stand%20cover.stl">bottom%20stand%20cover.stl</a>
+</li>
+<li><a href="bottom%20stand.FCStd">FreeCAD project</a>
+</li>
+</ul>
+
+<p>
+After assembly, it looks like this from the back:
+<img src="make,%203.png" class="img-responsive" alt="make,%203.png">
+</p>
+
+<p>
+Note, part of the body is deformed during printing. I have heated bed
+and I even printed raft support in Cura and it did not help. In my
+experience black PLA filament is awful in comparison to transparent
+one. Has inferior flow (results in slower print speed) and tends to
+deform easily. Will never buy it again.
+</p>
+
+<p>
+Fan top and bottom halves are attached using <a href="https://www.amazon.de/gp/product/B00OOLKD2G/ref=ppx_yo_dt_b_asin_image_o00_s00?ie=UTF8&psc=1">camera tripod quick
+release screw</a>.
+</p>
+</div>
+</div>
+</div><div class="col-md-3"><nav id="table-of-contents">
+<div id="text-table-of-contents" class="bs-docs-sidebar">
+<ul class="nav">
+<li><a href="#sec-1">1. General</a></li>
+<li><a href="#sec-2">2. Project description</a></li>
+</ul>
+</div>
+</nav>
+</div></div></div>
+<footer id="postamble" class="">
+<div><p class="author">Author: Svjatoslav Agejenko</p>
+<p class="date">Created: 2020-08-09 Sun 15:09</p>
+<p class="creator"><a href="http://www.gnu.org/software/emacs/">Emacs</a> 26.1 (<a href="http://orgmode.org">Org-mode</a> 9.1.9)</p>
+</div>
+</footer>
+</body>
+</html>
projects / physical.git / blobdiff