U.S. patent application number 13/392095 was filed with the patent office on 2012-07-05 for water analyzer comprising a pneumatically driven multi-chamber peristaltic pump.
This patent application is currently assigned to Hach Lange GmbH. Invention is credited to Kai Berggold, Aria Farjam, Bas De Heij, Ulrich Lundgreen, Rolf Uthemann.
Application Number | 20120167673 13/392095 |
Document ID | / |
Family ID | 41130364 |
Filed Date | 2012-07-05 |
United States Patent
Application |
20120167673 |
Kind Code |
A1 |
Farjam; Aria ; et
al. |
July 5, 2012 |
WATER ANALYZER COMPRISING A PNEUMATICALLY DRIVEN MULTI-CHAMBER
PERISTALTIC PUMP
Abstract
A water analysis device with a pneumatically actuated
multi-chamber peristaltic pump includes a base plate comprising a
plurality of proximally open pump chambers disposed on a proximal
side of the base plate. A pump membrane disposed on the proximal
side of the base plate is configured to close the pump chambers. A
cover plate is disposed on the pump membrane comprising a
respective pneumatic actuator channel in a region of each of the
pump chambers. The pneumatic actuator channel is configured to
connect to an overpressure source which actuates the pump membrane.
A connection channel formed as a groove on a distal side of the
base plate is disposed between two of the pump chambers. A separate
groove cover is disposed on the distal side of the base plate in a
region of the groove. The separate groove cover closes a distal
opening side of the groove.
Inventors: |
Farjam; Aria; (Duesseldorf,
DE) ; Uthemann; Rolf; (Leverkusen, DE) ;
Berggold; Kai; (Koeln, DE) ; Lundgreen; Ulrich;
(Guetersloh, DE) ; Heij; Bas De; (Dormagen,
DE) |
Assignee: |
Hach Lange GmbH
Berlin
DE
|
Family ID: |
41130364 |
Appl. No.: |
13/392095 |
Filed: |
March 31, 2010 |
PCT Filed: |
March 31, 2010 |
PCT NO: |
PCT/EP2010/054333 |
371 Date: |
March 22, 2012 |
Current U.S.
Class: |
73/64.56 |
Current CPC
Class: |
G01N 21/11 20130101;
G01N 2021/0325 20130101; G01N 21/05 20130101; B01L 3/50273
20130101; G01N 2021/054 20130101; G01N 35/1095 20130101; G01N
2021/0346 20130101; G01N 21/8507 20130101; B01L 3/502715 20130101;
G01N 21/645 20130101; G01N 2021/0321 20130101; G01N 2201/0218
20130101; B01L 2200/10 20130101; G01N 2001/4016 20130101; G01N
2201/024 20130101; F04B 43/082 20130101; B01L 2400/0481 20130101;
G01N 33/18 20130101; G01N 21/78 20130101; G01N 2021/8411 20130101;
F04B 43/12 20130101; B01L 2300/0627 20130101 |
Class at
Publication: |
73/64.56 |
International
Class: |
G01N 1/00 20060101
G01N001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 25, 2009 |
EP |
09168536.2 |
Claims
1-8. (canceled)
9. A water analysis device with a pneumatically actuated
multi-chamber peristaltic pump, the water analysis device
comprising: a base plate comprising a plurality of proximally open
pump chambers disposed on a proximal side of the base plate; a pump
membrane configured to be liquid-tight and elastic disposed on the
proximal side of the base plate, the pump membrane being configured
to close the proximally open pump chambers; a cover plate disposed
on the pump membrane, the cover plate comprising a respective
pneumatic actuator channel in a region of each of the proximally
open pump chambers, the pneumatic actuator channel being configured
so as to be connected to an overpressure source configured to
actuate the pump membrane, a connection channel disposed between
two of the proximally open pump chambers, the connection channel
being formed as a groove on a distal side of the base plate; and a
separate groove cover disposed on the distal side of the base plate
in a region of the groove, the separate groove cover being
configured to close a distal opening side of the groove.
10. The water analysis device as recited in claim 9, wherein the
base plate is an injection-molded plastic part.
11. The water analysis device as recited in claim 9, wherein the
separate groove cover is a flexible cover film.
12. The water analysis device as recited in claim 11, wherein the
flexible cover film is transparent.
13. The water analysis device as recited in claim 11, wherein the
base plate and the flexible cover film are each made of a same
plastic material and have a same melting temperature.
14. The water analysis device as recited in claim 9, wherein a
respective vertical channel is provided between the connection
channel and the proximally open pump chambers, the vertical
channels being disposed perpendicular to the connection
channel.
15. The water analysis device as recited in claim 9, wherein the
pneumatically actuated multi-chamber peristaltic pump is a
microfluidic peristaltic pump wherein a pumping volume of a pump
chamber is smaller than 10 .mu.l.
16. The water analysis device as recited in claim 9, wherein the
water analysis device further comprises a base module comprising
all electric components and an exchangeable cartridge module
comprising an entire fluidic system which comprises the
pneumatically actuated multi-chamber peristaltic pump.
Description
CROSS REFERENCE TO PRIOR APPLICATIONS
[0001] This application is a U.S. National Phase application under
35 U.S.C. .sctn. 371 of International Application No.
PCT/EP2010/054333, filed on Mar. 31, 2010 and which claims benefit
to European Patent Application No. 09168536.2, filed on Aug. 25,
2009. The International Application was published in German on Mar.
3, 2011 as WO 2011/023420 A1 under PCT Article 21(2).
FIELD
[0002] The subject matter of the present invention refers to a
water analysis device comprising a pneumatically operated
multi-chamber peristaltic pump.
BACKGROUND
[0003] In a water analysis device, liquids such as, for example, a
water sample, a liquid dialysate, a liquid analyte, a rinsing
liquid etc., are conveyed by pumps. If the analysis device is of a
microfluidic design, peristaltic pumps are the pump type of choice.
These comprise a plurality, for example, three, pump chambers which
are successively filled and emptied so as to cause a unidirectional
peristaltic pumping operation.
[0004] A microfluidic multi-chamber peristaltic pump is described
in U.S. Pat. No. 5,593,290 A which comprises three pump chambers
that are formed on the proximal side of a base plate and are each
closed with an elastic pump membrane. The adjacent pump chambers
are interconnected by a connection channel formed in the base plate
as a proximally open groove closed with an intermediate plate. In
the region of the pump chambers, the intermediate plate has
corresponding continuous openings. The proximal side of the
intermediate plate is provided with the elastic pump membrane, on
which a cover plate is fixed that comprises a pneumatic actuator
channel for each pump chamber.
[0005] Manufacturing this peristaltic pump is extremely intricate
since the base plate and the intermediate plate must be aligned
with each other with a tolerance of less than 0.1 mm. In order to
provide that the respective overall volumes of the three pump
chambers are as identical as possible, the intermediate plate is
formed by a thin film. It is technically challenging to provide the
continuous openings in the thin film with any accuracy.
SUMMARY
[0006] An aspect of the present invention is to provide a water
analysis device with a pneumatically operated multi-chamber
peristaltic pump that is simpler to manufacture.
[0007] In an embodiment, the present invention provides a water
analysis device with a pneumatically actuated multi-chamber
peristaltic pump which includes a base plate comprising a plurality
of proximally open pump chambers disposed on a proximal side of the
base plate. A pump membrane configured to be liquid-tight and
elastic is disposed on the proximal side of the base plate. The
pump membrane is configured to close the proximally open pump
chambers. A cover plate is disposed on the pump membrane. The cover
plate comprises a respective pneumatic actuator channel in a region
of each of the proximally open pump chambers. The pneumatic
actuator channel is configured so as to be connected to an
over-pressure source configured to actuate the pump membrane. A
connection channel is disposed between two of the proximally open
pump chambers. The connection channel is formed as a groove on a
distal side of the base plate. A separate groove cover is disposed
on the distal side of the base plate in a region of the groove. The
separate groove cover is configured to close a distal opening side
of the groove.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention is described in greater detail below
on the basis of embodiments and of the drawings in which:
[0009] FIG. 1 shows a schematic illustration of a water analysis
device formed by a base module and an exchangeable cartridge module
in which a pneumatically operated multi-chamber peristaltic pump is
arranged; and
[0010] FIG. 2 shows a longitudinal section of the peristaltic pump
in FIG. 1.
DETAILED DESCRIPTION
[0011] In the water analysis device of the present invention, the
connection channel between two pump chambers is formed as a groove
on the distal side of the base plate. In the region of the
connection channel groove, a separate groove cover is provided on
the distal side of the base plate, which closes the distal opening
side of the connection channel groove. The groove is thus now
provided on the side of the base plate averted from the pump
chambers. The groove may be closed with a simple groove cover. An
intermediate plate with recesses or openings is no longer needed.
The groove cover may be a large-surface body, for example, which
covers the entire distal side of the base plate. No exact
positioning of the groove cover is required, whereby the assembly
is much facilitated.
[0012] The pump chambers can be closed with a single pump membrane
or with separate pump membranes.
[0013] In an embodiment of the present invention, the base plate
can, for example, be an injection molded plastic part comprising
all pump chambers and the connection channels in the form of
grooves. Since the base plate has recesses only on the distal and
the proximal sides of the base plate, remolding poses no
problems.
[0014] In an embodiment of the present invention, the groove cover
can, for example, be a flexible cover film. The cover film is of
limited flexibility so that it can adapt to irregularities on the
distal side of the base plate. Leaks caused by irregularities;
which would otherwise almost be inevitable with a rigid groove
cover, are thereby avoided. Using a flexible cover film for the
groove cover allows neglecting a high planarity on the distal side
of the bas plate.
[0015] In an embodiment of the present invention, the cover film
can, for example, be transparent. The cover film is, for example,
transparent to laser radiation used to weld the cover film to the
base plate. The transparence of the cover film thus makes it
possible to weld the cover film to the base plate by laser welding.
This allows for a reliably fluid-tight fixing of the cover film by
means of an automated and thus cost-efficient manufacturing
process.
[0016] In an embodiment of the present invention, the base plate
and the cover film can, for example, be made from the same plastic
material so that they have the same melting temperature. This
facilitates the welding of the cover film to the base plate by
laser welding.
[0017] In an embodiment of the present invention, respective
vertical channels can, for example, be provided between the
connection channel of the distal side of the base plate and the
pump chambers, which vertical channels are perpendicular to the
connection channel and respectively connect the pump chambers to
the connection channel. Since the vertical channels have the same
demolding direction as the pump chambers on the proximal side and
the connection channel groove on the distal side of the base plate,
the base plate can readily be made by injection-molding a plastic
material.
[0018] In an embodiment of the present invention, the peristaltic
pump can, for example, be a microfluidic peristaltic pump, wherein
the pumping volume of a pump chamber is smaller than 10 .mu.l.
Observing the allowable tolerances is technically challenging, for
example, with a microfluidic peristaltic pump, so that, for
example, with respect to microfluidic peristaltic pumps, the
present invention will lead to particular simplifications in the
manufacture of a water analysis device using such a peristaltic
pump.
[0019] In an embodiment of the present invention, the water
analysis device can, for example, be formed by a base module
including all electric components and an exchangeable cartridge
module comprising the entire fluidic system including the
peristaltic pump. The cartridge module may be a one-way article
that is replaced and discarded when depleted or damaged.
[0020] In a schematic general view, FIG. 1 illustrates a process
water analysis device 10 used for a quasi-continuous quantitative
determination of an analyte in water 11. In the present case, the
water analysis device 10 is fully immersed into the water 11 to be
analyzed, i.e., it is designed as a so-called immersion probe. The
water analysis device 10 is modular and is formed by a base module
12 containing all electric components and an exchangeable cartridge
module 14 comprising the entire fluidic system which, in the
present instance, is of microfluidic design. The cartridge module
14 is used only once and is replaced and discarded when depleted or
in the event of a defect.
[0021] The cartridge module 14 comprises a carrier liquid tank 16
connected to the pump inlet of a pneumatically operated
multi-chamber peristaltic pump 18 via a liquid conduit. The pump
outlet of the peristaltic pump 18 is connected to a dialysis
element 20 via a liquid conduit, in which element the analyte
migrates from the water 11 into the carrier liquid.
[0022] A liquid conduit connects the dialysis element 20 to a
measurement section 22, with a reagent being introduced at some
point along this liquid conduit, which reacts, for example, in a
color changing manner with the analyte to be determined. The
measurement section 22 is associated with an analysis device 24 on
the side of the base module, which device may, for example, be
designed as a photometer, and determines the extinction of the
liquid in the measurement section 22. The liquid is thereafter
pumped into a waste tank 28.
[0023] The part of the peristaltic pump 18 on the side of the
cartridge module is formed by a pump system whose actuation system
is arranged in the base module 12. The actuation system is formed
by an overpressure accumulator 30 and a vacuum accumulator 32, a
pneumatic pump (not illustrated) that is connected to the
overpressure accumulator 30 and the vacuum accumulator 32 and
generates the necessary overpressure and vacuum, respectively, and
three electrically switched change-over valves 34 that connect
either the overpressure accumulator 30 or the vacuum accumulator 32
to the associated pump membrane of the peristaltic pump 18.
[0024] The peristaltic pump 18 is shown in detail in FIG. 2. The
peristaltic pump 18 comprises a plastic material base plate 40
which has its proximal side provided with three pump chambers 41,
42, 43 as spherical recesses having a proximal opening. On the
proximal side 44 of the base plate 40, a liquid-tight and elastic
pump membrane 46 is arranged that closes the openings of the three
pump chambers 41, 42, 43. The pump membrane 46 is formed from a
fluorinated or partly fluorinated elastomer, for example, a
material known by the name Viton, and has a thickness of 0.1 to 0.4
mm. As an alternative, the pump chambers 41, 42, 43 could also be
closed with a separate individual pump membrane. Such a membrane
may be formed by a circular membrane with an annular bead at the
edge.
[0025] Proximal of the pump membrane 46, a cover plate 48 is
applied onto the pump membrane 46, wherein the cover plate 48 has
three pneumatic actuator channels 51, 52, 53 which are
approximately perpendicular to the base plane of the base plate 40,
each being aligned with the respective pump chamber 41, 42, 43 and
ending approximately in the center of the pump chamber
openings.
[0026] From each pump chamber 41, 42, 43, two vertical channels
60-65 respectively extend transversely to the base plane of the
base plate 40 to the distal side of the base plate 40. Each pump
chamber 41-43 has a respective vertical inlet channel 60, 62, 64
and a respective vertical outlet channel 61, 63, 65. The vertical
outlet channel 61 of the first pump chamber 41 is connected to the
vertical inlet channel 62 of the second pump chamber 42 through a
horizontal connection channel 71. The vertical outlet channel 63 of
the second pump chamber 42 is connected to the vertical inlet
channel 64 of the third pump chamber 42 through another horizontal
connection channel 73. The two connection channels 71, 73 are each
formed as a distally open groove 70, 72 on the distal side of the
base plate 40. In the region of the connection channels 71, 73, the
distal side of the base plate 40 is covered by a separate groove
cover 80 which is formed by a flexible transparent cover film 80
and distally covers the two connection channel grooves 70, 72.
[0027] The base plate 40 and the cover film 80 are made from the
same plastic material so that they have the same melting point, and
they are welded together fluid-tightly by laser welding or
ultrasound welding. Heat sealing or thermal bonding can
alternatively be used.
[0028] The vertical inlet channel 60 in the first pump camber 41
forms the pump inlet and the vertical outlet channel 65 of the
third pump chamber 43 forms the pump outlet.
[0029] By correspondingly switching the associated change-over
valve 34, pneumatic overpressure can be applied onto the proximal
rear side of the pump membrane 46 through the actuator channels 51,
52, 53 so that the contents of the respective pump chamber 41, 42,
43 is expelled. By changing over the change-over valve 34, vacuum
can be applied from the vacuum accumulator 32 onto the proximal
rear side of the pump membrane 46 so that the same is withdrawn
into the initial position illustrated in FIG. 2, whereby the
respective pump chamber 41, 42, 43 is filled.
[0030] By filling the first pump chamber 41 and by subsequently
filling the second pump chamber 42 while the first pump chamber 41
is emptied at the same time, and by subsequently filling the third
pump chamber 43 while the second pump chamber 42 is emptied at the
same time, a peristaltic pumping of the liquid from the pump inlet
to the pump outlet is realized.
[0031] The absolute pressure in the overpressure accumulator 30 is
at approximately 2.0 bar, and the absolute pressure in the vacuum
accumulator 32 is at approximately 0.5 bar.
[0032] The largest diameter of the pump chambers 41-43 is 1.0 to
5.0 mm, the vertical height is 0.1 to 2.0 mm, so that he pump
chambers 41-43 have a volume of approximately 1.0 to 20 .mu.l,
respectively.
[0033] The present invention is not limited to embodiments
described herein; reference should be had to the appended
claims.
* * * * *