Versatile and mechanical 7-segment display unit by shiura

Last crawled date: 3 years, 3 months ago

A single unit of mechanical 7-segment display driven by a small hobby servo.
This unit can be used solely as a kitchen timer, dice, single digit clock, etc.
You can make digital clock, score board, counter, etc .. if you make two or more.
Two versions are provided. One has digits in ascending-order, and the other is optimized. Latter one has a special order (1 7 4 5 6 0 8 9 3 2) to decrease the load to the servo with less flipping segments between neighboring digits.
Spec
Overall size : 10cm (H) x 6cm (W)
Digit size : 8cm x 4cm (area in the center lines of segments)
You need additional parts as follows
Mini servo* (SG90 type : around 3USD per unit) comes with two screws
Control circuit (I use micro:bit and breakout board Ks0360. Codes provided)
4 Screws (M2.5 - M3)
Paint
Lubricant
*It requires 162degrees rotation to show the all of 0 - 9. I use the servo below. In the spec sheet, rotation angle is limited to 120deg., but actually it can rotate upto 180deg., using PWM output of micro:bit.https://www.amazon.co.jp/gp/product/B07PHFQY6B/
Tools:
Soldering iron for plastic welding
drill and screw tap (if you do not use tapping screw)
files or a fine knife
This thing is a reduced version of "Mechanical 7-segment digital clock",https://www.thingiverse.com/thing:4626956
for ease to make. Since hobby servo is attached to the axis directly, it can show any single number within 0.2sec. It is not necessary to adjust origin at each power on.
I hope you make anything useful or just interesting, using this unit and show your make.
Dec. 19, 2020 : I have added easy to assemble version. It requires support when printing, but all cams are already assembled.