User's Manual

®
Model No. ME-6984 Operation
5
the piston of the smaller syringe than it is to push on the piston of the larger syringe. Can you push the 20 mL
syringe’s piston all the way in? If so, can you push the 60 mL syringe’s piston all the way in while holding the 20
mL syringe’s piston in place?
To find out how the various components work together, set up the following combination of parts: 20 mL syringe,
check valve, bleeder valve, syringe coupler, and hydraulic cylinder. Start with the pistons of both the hydraulic
cylinder and the 20 mL syringe pushed all the way in.
• Connect the check valve assembly to the 20 mL syringe.
• Connect the bleeder valve to the check valve assembly.
• Connect the syringe coupler from the bleeder valve to the male luer lock on the hydraulic cylinder.
• Twist the handle on the stopcock of the bleeder valve to the closed position.
• Pull out the piston of the 20 mL syringe until the tip of the piston is at the 20 mL mark on the syringe.
• Next, push the piston of the syringe all the way in. What happens to the hydraulic cylinder? You should have
noticed that the piston of the hydraulic cylinder moved out until the tip of the piston was close to the 20 mL
mark on the cylinder. Try it again.
• Pull the piston of the 20 mL syringe so the piston is next to the 20 mL mark. Did the piston of the hydraulic
cylinder go back into the cylinder as you pulled the piston out of the syringe? The piston of the hydraulic
cylinder should not have moved because the check valve assembly only allows fluid to flow in specific
directions. Next, push the piston of the syringe all the way in. The piston of the hydraulic cylinder should
move to the 40 mL mark (approximately).
• Repeat the procedure a third time and see whether the piston in the hydraulic cylinder was able to move to
the 60 mL mark.
To empty the hydraulic cylinder without disconnecting any tubing, twist the handle of the stopcock to the open
position and push the piston of the hydraulic cylinder all the way in. Fluid can flow out of the bleeder valve, but
cannot go back into the cylinder of the 20 mL syringe because of the one-way check valve.
Syringe
Coupler*
20 mL
Syringe
60 mL
Syringe
Figure 7: Demonstration
*not to scale
20 mL
Syringe
Check
Valve
Assembly
Bleeder
Valve*
Syringe
Coupler*
Hydraulic
Cylinder
*not to scale
Figure 8: Example
Stopcock