Syringe dosing unit

thingiverse

Almost complete design finalized. Modifications planned in the future to address issues below. 14.11.2017 - New models uploaded, minor issues resolved 15.11.2017 - Successful test conducted with custom Arduino code. Future changes are being considered - the syringe can be inserted from the side, and sliding elements will be added to the middle section due to printed parts having movement resistance. Sometimes the coupling disconnects in a backward motion, which could be prevented by using a small dowel (0.8mm) or purchasing a metal coupling from eBay. A positive aspect is that the Arduino, motor driver, and motor can be powered solely through USB. This enables the creation of a simple dosing unit that operates on USB power or a powerbank alone. Part List --------------------- - 3 printed parts + 1 printed motor coupling - Syringe (e.g., "BD" syringe) with a volume of 20mL - Stepper motor 28BYJ-48 and driver electronics - 2x M3 screw and nuts - About 60-65mm M5 screw - 3x sliding rods, each measuring 175mm - Aluminum tube (approximately 60mm long) with a diameter of 12mm and a wall thickness of 1mm - An M5 nut is glued into the aluminum tube using epoxy resin Notices --------------------- - Thin lubrication of the rod is highly recommended - Lubrication of the threaded rod M5 is necessary - If the coupling is not secure on the motor, use a small dowel (0.5-1mm) and drill it through both the motor shaft and coupling. This will ensure proper securing. - If the middle section is not moving smoothly on the sliding rods, polish them and apply lubricant. If this does not resolve the issue, use a 4.0 - 4.1mm drill to clear holes for easier sliding. Alternatively, professional sliding bearings can be used (e.g., made from brass or IGUS).