Small extractor fan assembly for Litter Robot

thingiverse

# Window Vent Assembly for Litter Robot The litter robot 3 (Open Air) has a weird little sweeping guard on the inside that always got clogged up when we used clumping clay litter. So I took it off. This left a convenient port on the center back of the glob. Attach a 33mm vacuum hose to that port and the other end to this assembly, add a 120mm computer fan and voila, your littler box has an extraction fan and your life can smell better. ## The assembly ### Window (.svg / .dxf) Get some clear acrylic laser cut with this pattern or one that fits your window better. My window is tall and narrow and slides open horizontally so I needed a tall skinny insert. I made the insert in two parts so that in the summer I could leave the top half open. The important part is that the insert gets wedged securely in your open window and the assembly gets screwed in over the circular hole. Makes an acrylic sandwich. ### Outside (.stl) Just a set of louvers to protect the fan in case it might rain some in your area. Optional. ### Inside (.stl) 33mm vacuum host attaches to the narrow end of the horn. Square plate gets screwed into the window so the cirular holes line up. Pop a 120mm computer fan into the box and optionally screw or wedge it in place. Power supply left as an exercise to the reader ;-). ## Rebuilding I used OpenSCAD. Requires [scad-utils](https://github.com/OskarLinde/scad-utils) and [list-comprehension-demos](https://github.com/openscad/list-comprehension-demos) be installed in your path. Use modifier characters to show just the parts you need, render, export. ## Caveat I haven't built this yet! Cross your fingers that it works.