|
The smart flow rate controller
- A new generation of passive flow restrictor
 The
ChronoflowTM device is based on a very simple principle of
a flow restrictor which is made out of a channel in a plate, preferably
manufactured out of silicon etching or micro-plastic injection. On top
of that plate, a membrane is placed which deformation is directly resulting
from the difference between the output and input pressure. The membrane
will cover a given part of that plate, depending on the pressure difference,
therefore determining the length of the flow restrictor channel (see drawing
in the brochure). The channel being precisely designed (in a shape) according
to the membrane deformation, the flow will remain stable whatever the
pressure difference is.
ChronoflowTM, therefore, is a very innovative new generation
of flow restrictor which can be used in different ways :
1- With an elastomeric device (or any pressurized drug container), where
the accuracy of the inlet pressure will not be needed anymore and the
flow rate will remain accurate over the entire use of the device; this
is not the case today with existing elastomeric devices (in particular
for 24h or more), since the pressure does not remain stable over a long
period of time and is depending on the shape of the elastomeric device.
Furthermore, because the occlusion than small capillaries.
Therefore, the ChronoflowTM can be used either with a standard
bag on which a pressure is build (without any accuracy) or with elastomeric
systems in order to launch a second generation elastomeric device, where
the accuracy will be maintained over the entire infusion. We have today
designed ChronoflowTM devices for flow rates as low as 0.5ml/h.
2- With large bags of fluids for IV infusion, by use of a preset ChronoflowTM
for a given constant flow rate. In that case it can be used either with
gravity or with a pressurized bag (which can be easily obtained with a
re-usable and low-cost pressurizing system to be applied on a standard
bag) and secure a constant flow rate over the emptying of the bag. With
a certain design of the ChronoflowTM, a preset multi-rate system
can also be obtained.
Major advantages
- Automatic pressure compensation.
- Accurate flow rate over time.
- No external energy source.
- Built-in safety features.
- Easy priming.
- Low cost.
| Technical specifications
(examples) |
| Flowrate |
1
ml/h |
| Pmin |
1.45
psi (100 mbar) |
| Pmax |
8.7
psi (600 mbar) |
| Accuracy |
±5% |
| Automatic
occlusion |
600
mbar |
| Chip
dimensions |
13
x 13 mm |
 |
|
The ChronoFlow DIGITAL Control Unit
 With
an electronic duty cycle controller, any programmed flow rate can be obtained.
This is the "Digital Chronoflow" device. This device is controlling
the opening and closing of a valve which is build into the ChronoflowTM.
The result is a programmable low-cost device with very little energy consumption.
The driving energy for the fluid is coming from a pressurized bag, while
the accuracy can be obtained from the ChronoflowTM
As an example, with a ChronoflowTM at 300ml/h,
a flow rate of 150ml/h can be obtained with a duty cycle of 50% (e.g. 30
sec. On, 30 sec. OFF).
Major advantages
- Programmable injection profile.
- Programmable flow rate.
- Easy to use and to program.
- Very low power consumption.
- Extremely small and lightweight.
- Low cost control unit and disposables.
- Patient Protected.
The ChronoFlowTM device was presented as a
poster entitled
"IMPROVED MICRO-FLOW REGULATOR FOR DRUG DELIVERY SYSTEMS"
download the full article
PDF format 852Kb
|
