Valves

Useful links

Here is the link to the liquid handling page. Here is the link to the syringe pump page.

Here is a link to automating the six port valve.

Automating the 3-2 Hamilton Valve

The photo on the left shows a Hamilton 3-2 manual valve connected to a servo motor. The motor can change the fluid path, to connect the center port to either of the two other ports. This choice can be dictated by a computer controlled microcontroller.

Parts of the automated valve

The valve itself needs to be held in a housing that includes a 3d printed plastic part and an aluminum channel. There is also a 3D printed spacer, a Servo motor (source), a servo connector (source) and a brass adapter to make the connector fit the shaft of the valve.

Hamilton 3 port, two way valve

This link will take you to the Hamilton Valve page where you can purchase this valve. In October 2024, the price was $125. The ports are threaded for 1/4 x 28 fittings such as those found here. The cost of some of these fittings in late 2024 are listed near the bottom of the fluid handling page.

Switchable Flow Path Options

The center port can be connected to either a port on the left or one on the right. In our applications, the pump is connected to the center port and the others lead to the reservoir or the output.

Controlling a servo with Arduino

The Arduino Servo library makes it simple to control the valve.

The code to the left is a slightly modified example of Arduino code that allows the user to control a valve from a serial monitor. Open the serial monitor from the "Tools" dropdown, set the baud rate to 115200, and type in the angle you wish in degrees. When you hit the enter button, the servo will turn to that angle.