Final Design

Fig 1 The new design with annotated key components

The final design is a crank-open device with pulleys. This final design is able to provide 65 lbs throughout compression process. The team performed several testing and the device is able to empty the IV bag in 2.5 minutes. Here are some close-up to the key components.

Close-up

Crank Assembly

- Winding the crank separates the top and the middle plates allowing for the IV bag to be loaded into the device

- Great mechanical advantage: The handle requires around a 6lb force applied to the center pulley.

Fig 2. Crank assembly

Locking Pawl and Gear

- Holds the device open by locking in with the gear

- Springs attached to the pawl apply tension necessary to lock it

- Device can be engaged by a toggle switch that releases the pawl from gear

Fig 3. Locking Pawl and Gear

Constant Force Springs and Retainer

- Provides a constant force needed to squeeze the IV bag.

- The device is loaded with 4 springs with a total of 52lb force when the device is fully opened.

Fig 4. Constant Force Springs and Retainer

Braided Wires and Pulleys

- Braided wire is wrapped around multiple pulleys and moves the middle plate away from the top plate

Fig 5. Braided Wires and Pulleys

Middle Plate - Recessed areas to prevent clamping on IV tubing and bag hook

- Once the bag is placed into device, no adjustments are needed.

Fig 6. Middle Plate