U.S. patent application number 14/711225 was filed with the patent office on 2015-11-19 for membrane pump.
The applicant listed for this patent is SAINT-GOBAIN PERFORMANCE PLASTICS FRANCE. Invention is credited to Julien Benoit, Alban Letailleur, Roland Lucotte.
Application Number | 20150330383 14/711225 |
Document ID | / |
Family ID | 51063707 |
Filed Date | 2015-11-19 |
United States Patent
Application |
20150330383 |
Kind Code |
A1 |
Letailleur; Alban ; et
al. |
November 19, 2015 |
MEMBRANE PUMP
Abstract
A pump comprising a pump body defining a circulation space for
circulation of fluid according to a direction of circulation from
an entry orifice of the circulation space to an output orifice of
the circulation space; a membrane retained in the circulation space
substantially parallel to the direction of circulation; and an
actuating device adapted to vibrate the membrane in a direction
substantially perpendicular to the direction of circulation,
wherein the membrane comprises a material or a protective coating
having a polymer organic matrix with a Young's modulus in a range
of between 100 MPa and 10 GPa.
Inventors: |
Letailleur; Alban; (Paris,
FR) ; Lucotte; Roland; (Bussieres, FR) ;
Benoit; Julien; (Manziat, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAINT-GOBAIN PERFORMANCE PLASTICS FRANCE |
Charny |
|
FR |
|
|
Family ID: |
51063707 |
Appl. No.: |
14/711225 |
Filed: |
May 13, 2015 |
Current U.S.
Class: |
417/472 |
Current CPC
Class: |
F04B 43/14 20130101;
F04B 43/0018 20130101; F04B 43/021 20130101; F04B 43/04 20130101;
F05C 2225/04 20130101; F04B 43/0054 20130101 |
International
Class: |
F04B 43/04 20060101
F04B043/04 |
Foreign Application Data
Date |
Code |
Application Number |
May 14, 2014 |
FR |
1454290 |
Claims
1. A pump comprising: a pump body defining a circulation space for
circulation of fluid according to a direction of circulation from
an entry orifice of the circulation space to an output orifice of
the circulation space; a membrane retained in the circulation space
substantially parallel to the direction of circulation; and an
actuating device adapted to vibrate the membrane in a direction
substantially perpendicular to the direction of circulation,
wherein the membrane comprises a material or a protective coating
having a polymer organic matrix with a Young's modulus in a range
of between 100 MPa and 10 GPa.
2. The pump according to claim 1, wherein the polymer organic
matrix of the membrane or of the protective coating of the membrane
comprises a fluoropolymer.
3. The pump according to claim 1, wherein the pump further
comprises at least one seal, and wherein the at least one seal
comprises a fluoropolymer.
4. The pump according to claim 1, wherein the pump further
comprises: a support connected to an end of the membrane, wherein a
projecting part of the support passes in a sealed manner towards
the exterior of the pump body, and wherein the actuating device is
adapted to act on the projecting part of the support to generate in
an excitation force at the end of the membrane.
5. The pump according to claim 4, wherein the support comprises a
polymer material, and wherein the polymer material of the support
is the same as a polymer material of the protective coating of the
membrane.
6. The pump according to claim 4, wherein at least one of the
membrane and the support comprises at least one peripheral orifice
and at least one central orifice.
7. The pump according to claim 1, wherein the pump body comprises a
polymer.
8. The pump according to claim 7, wherein the polymer is
fiber-reinforced.
9. The pump according to claim 1, wherein the pump body comprises a
first rigid wall and a second rigid wall opposite one another and
defining therebetween the circulation space.
10. The pump according to claim 9, wherein the membrane comprises a
disc, and wherein the membrane is retained in the circulation space
substantially parallel to the first and second rigid walls.
11. The pump according to claim 1, wherein the entry orifice opens
into the circulation space in the vicinity of the periphery of the
membrane, and wherein the output orifice opens into the circulation
space in the vicinity of a central area of the membrane.
12. The pump according to claim 1, wherein the pump body further
comprises a first flange defining a first wall and a second flange
defining a second wall, wherein the first and second walls define
between them the circulation space, and wherein the first flange
defines the entry orifice and the output orifice.
13. The pump according to claim 1, wherein the actuating device
comprises at least one electromagnetic linear actuator powered by
an alternating current.
14. The pump according to claim 1, further comprising at least one
ferromagnetic element coupled to the actuating device.
15. The pump according to claim 1, further comprising at least one
fluid flow sensor connected with the actuating device.
16. The pump according to claim 1, wherein the material or the
protective coating has a polymer organic matrix with a Young's
modulus in a range of between 200 MPa and 2 GPa.
17. The pump according to claim 1, wherein the pump further
comprises a check valve disposed at the output orifice.
18. The pump according to claim 1, wherein the membrane has a
discoidal geometry.
19. A fluid displacement apparatus comprising a high flow rate
distribution pump and a membrane pump according to claim 1, wherein
the membrane pump is connected to an outlet of the distribution
pump.
20. A container-mixer comprising: a container adapted to receive a
fluid, the container comprising a flexible material; and a pump
according to claim 1 disposed in the container.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 U.S.C.
.sctn.119(b) to French Patent Application No. 1454290 entitled
"POMPE A MEMBRANE," by Alban Letailleur, et al., filed May 14,
2014.
FIELD OF THE DISCLOSURE
[0002] The present invention relates to a pump for moving fluids,
and more particularly to a pump for applications where the fluids
to be moved are fluids that are not to be contaminated or damaged,
such as biological fluids or high purity fluids, or where the
fluids to be moved are aggressive fluids, such as for example those
used for the manufacture of semiconductor components.
RELATED ART
[0003] To move a solution or a fluid suspension, it is known to use
a centrifugal pump comprising an impeller in a pump body. The
impeller is typically operated by means of a shaft which passes
outwardly from the pump body and which is rotated by an external
motor. A drawback of such a centrifugal pump is that there is a
risk of contamination or leakage at the bearing through which the
drive shaft of the impeller passes. Moreover, the rotation of the
impeller in operation generates shear stresses in the fluid, which
are disadvantageous in the case of fragile fluids, particularly
biological fluids.
[0004] Another disadvantage of such a centrifugal pump is that it
is not adapted to move aggressive fluids, which tend to destroy the
mechanical bearings. Examples of aggressive fluids include
suspensions used in CMP (Chemical-Mechanical Planarization)
polishing processes which are designed to planarize the surface of
semiconductor components. These suspensions can have very fine
particles that tend to mechanically attack the bearings.
[0005] Industries continue to demand improved pumps.
SUMMARY
[0006] It is these disadvantages which the invention is more
particularly intended to eliminate, by disclosing a pump that
provides effective displacement of fluid, both for small volumes
and large volumes of fluid, the pump making it possible to obtain a
stable fluid flow rate over time while providing the ability to
modulate the fluid flow rate over a wide range of flow rates, the
structure of the pump being further adapted to limit the risk of
contamination or damage to the fluid to be moved, and enabling use
with aggressive fluids.
[0007] A pump in accordance with one or more of the embodiments
described herein can generally include a pump body which defines a
circulation space for circulation of fluid according to a direction
of circulation from an entry orifice of the circulation space to an
output orifice of the circulation space. The pump can further
include a membrane retained in the circulation space substantially
parallel to the direction of circulation; and an actuating device
adapted to vibrate the membrane, in a direction substantially
perpendicular to the direction of circulation. In an embodiment,
the membrane may include a protective coating made of a material
having a polymer organic matrix with a Young's modulus in a range
of between 100 MPa and 10 GPa, such as in a range of between 200
MPa and 2 GPa. Within the meaning of the invention, a "protective
coating" is an external part of the membrane intended to be in
contact with the fluid during operation of the pump, it being
understood that the remainder of the membrane, apart from the
protective coating, is configured not to be in contact with the
fluid. According to the invention, a fluid is a deformable medium
which can be moved, such as a liquid, a gas, a gel, a paste, a
powder, a suspension, a dispersion, an emulsion, or a mixture of
these. In an embodiment, the membrane is made of a material having
a polymer organic matrix with a Young's modulus in a range of
between 100 MPa and 10 GPa, such as between 200 MPa and 2 GPa.
Throughout this application, numerical values of the Young's
modulus are given as measured at 23.degree. C.
[0008] In an embodiment, the membrane or the protective coating of
the membrane may be integrally made of a polymer organic material
having a Young's modulus in a range of between 100 MPa and 10 GPa,
such as in a range of between 200 MPa and 2 Gpa. In another
embodiment, the membrane or the protective coating of the membrane
can be made of a composite material comprising a polymer organic
matrix having a Young's modulus in a range of between 100 MPa and
10 GPa, such as in a range of between 200 MPa and 2 GPa, and a
reinforcement, in particular a fibrous reinforcement, woven or
nonwoven, for example based on glass fibers.
[0009] According to certain embodiments of the invention, the pump
can be disposed within a container designed to receive at least one
fluid, wherein the container is made of flexible material.
[0010] A pump with a vibrating membrane as described above may
avoid use of mechanical bearings in the pump body, thereby reducing
the risk of contamination and leakage. In addition, such a membrane
pump can generate little shear stress in the fluid displaced,
thereby maintaining integrity of the fluid components while
ensuring a high level of fluid displacement. It is possible with
such a pump to modulate the fluid flow rate over a wide range, such
as for example, from 0.1 L/min to 100 L/min. It is also possible,
for a given value of the fluid flow, to obtain a good stability of
the fluid flow over time. Another advantage of a pump with a
vibrating membrane in accordance with embodiments described herein
is that the pump can be self-priming. That is, the pump does not
need to be initially filled with the fluid in order to operate.
Rather, in practice, the pump can move a certain quantity of air,
thus creating a vacuum in the upstream circuit, which allows fluid
to flow into the circulation space.
[0011] In a particular embodiment, the membrane, or protective
coating of the membrane, can include a polymer organic material
having a relatively high Young's modulus in a range of between 100
MPa and 10 GPa, such as between 200 MPa and 2 Gpa. To the contrary,
elastomers such as silicone or polyurethane elastomers have Young's
moduli in a range of between 1 MPa and 10 MPa. It is the merit of
the inventors to have found that a membrane made of a material with
a polymer organic matrix having a Young's modulus in a range of
between 100 MPa and 10 GPa, or a protective coating made of a
material with a polymer organic matrix having a Young's modulus in
a range of between 100 MPa and 10 GPa, is capable not only of
providing a function of fluid propulsion when integrated in a pump
with vibrating membrane, but also is able to withstand degradation,
especially when the pump is used to move a mechanically aggressive
fluid, such as the suspensions used in the CMP polishing
processes.
[0012] In addition, polymer organic materials having a Young's
modulus in a range of between 100 MPa and 10 GPa can also be
chemically more stable than silicone or polyurethane elastomers,
and less likely to be chemically modified through contact with
fluids flowing in the pump.
[0013] According to one aspect of the invention, the actuating
device can be configured to generate alternately at an end of the
membrane situated in the vicinity of the entry orifice of the
circulation space, an excitation force which is substantially
perpendicular to the direction of circulation.
[0014] According to further embodiments of the invention, the
membrane can be arranged so that in response to application of an
excitation force alternately to one end of the membrane, in a
direction substantially perpendicular to the membrane, while the
membrane extends parallel to the direction of circulation, at least
one undulation of the membrane appears and spreads along the
membrane from its end subjected to the excitation force towards
another end of the membrane.
[0015] In this way, the membrane can constitute a support for
displacement of waves from its end which is subjected to the
excitation force to its other end. The displacement of these waves
can be accompanied by forced damping in the fluid circulation
space. Transfer of mechanical energy can thus be established
between the membrane and the fluid in the form of a pressure
gradient and a fluid flow.
[0016] According to a particular embodiment, the excitation of the
membrane can be performed at one of the natural frequencies of the
membrane, and in particular the first natural frequency of the
membrane. In an embodiment, to avoid localized pressure effects in
the fluid, the excitation frequency of the membrane can have a
value in the range of between 20 Hz and 300 Hz, such as in a range
of between 40 Hz and 150 Hz.
[0017] At rest, the membrane can be held solely at its periphery.
Upon actuation, the surface area of the membrane increases with the
formation of waves, resulting in a tension of the membrane in
operation, due to the holding at the periphery of the membrane. The
periphery of the membrane can be engaged with a peripheral rigid
support. The support may exert at the periphery of the membrane
efforts to force the return of the membrane in a plane of extension
of the support. In the case of discoidal membrane geometry, the
support may be a ring, which exerts radiating efforts at the
periphery of the membrane.
[0018] In an embodiment, a polymer organic matrix of the membrane
or of the protective coating of the membrane can be made of a
fluoropolymer. In the context of the invention, the term
"fluoropolymer" refers to any polymer having in its chain at least
one monomer chosen from compounds containing a vinyl group capable
of opening to polymerize, or propagating a polymerization reaction,
and which contains, directly attached to this vinyl group, at least
one fluorine atom, a fluoroalkyl group or a fluoroalkoxy group.
Examples of monomers include vinyl fluoride; vinylidene fluoride
(VF2); trifluoroethylene (VF3); chlorotrifluoroethylene (CTFE);
1,2-difluoroethylene; tetrafluoroethylene (TFE);
hexafluoropropylene (HFP); perfluoro(alkylvinyl)ethers, such as
perfluoro(methyl vinyl)ether (PMVE), perfluoro(ethylvinyl)ether
(PEVE) and perfluoro(propyl vinyl)ether (PPVE); perfluoro
(1,3-dioxole); perfluoro (2,2-dimethyl-1,3-dioxole) (PDD); the
product of formula
CF.sub.2.dbd.CFOCF.sub.2CF(CF.sub.3)OCF.sub.2CF.sub.2X wherein X is
SO.sub.2F, CO.sub.2H, CH.sub.2OH, CH.sub.2OCN or
CH.sub.2OPO.sub.3H; the product of formula
CF.sub.2.dbd.CFOCF.sub.2CF.sub.2SO.sub.2F; the product of formula
F(CF.sub.2).sub.nCH.sub.2OCF.dbd.CF.sub.2 wherein n is 1, 2, 3, 4
or 5; the product of formula R.sub.1CH.sub.2OCF.dbd.CF.sub.2
wherein R.sub.1 is hydrogen or F(CF.sub.2).sub.z and z is 1, 2, 3
or 4; the product of formula R.sub.3OCF.dbd.CH.sub.2 wherein
R.sub.3 is F(CF.sub.2)z- and z is 1, 2, 3 or 4;
perfluorobutylethylene (PFBE); 3,3,3-trifluoropropene;
2-trifluoromethyl-3,3,3-trifluoro-1-propene. The fluoropolymer may
be a homopolymer or a copolymer, it may also include
non-fluorinated monomers such as ethylene. In a more particular
embodiment, the fluoropolymer is selected from: fluorinated
ethylene propylene (FEP), ethylene tetrafluoroethylene (ETFE),
polytetrafluoroethylene perfluoropropylvinyl ether (PFA),
polytetrafluoroethylene perfluoromethyl vinyl ether (MFA),
polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF),
ethylenechlorotrifluoroethylene (ECTFE),
polychlorotrifluoroethylene (PCTFE), or a combination thereof.
[0019] In an embodiment, the entire pump body can be made of a
fluoropolymer, optionally fiber-reinforced, in particular with
glass fibers. In another embodiment, each seal of the pump can be
made of a fluoropolymer. Fluoropolymers can make it possible to
avoid any possibility of contamination, which may be advantageous
for high purity applications. Fluoropolymers can also have the
advantage of being resistant to chemicals, especially to acids such
as sulfuric acid (H.sub.2SO.sub.4), hydrofluoric acid (HF) or
phosphoric acid (H.sub.3PO.sub.4) which are used in particular for
the manufacture of semiconductors.
[0020] According to one aspect of the invention, the pump can
comprise a support, which can be connected to the end of the
membrane. The support may be of sufficient strength to withstand
the excitation force, and at least a projecting part of which
passes in a sealed manner towards the exterior of the pump body,
the actuating device being configured to act on this projecting
part of the support, such as to generate the excitation force at
the end of the membrane in an alternating manner.
[0021] According to one embodiment, the support can be made of a
different polymer material than the material of the membrane or of
the protective coating of the membrane. In a particular embodiment,
the support can be made of a material selected from polycarbonate,
polyphenylene sulfide (PPS), or polypropylene, possibly reinforced
by fibers, especially glass fibers. The membrane can then be
overmolded on the support, which can save time in assembly of the
pump, while improving the adhesion and coupling between the
membrane and the support.
[0022] According to another embodiment, the support can be made of
a same polymer material as the polymer organic matrix of the
membrane or of the protective coating of the membrane. The support
can then be formed integrally with the membrane, in particular by
molding.
[0023] According to one aspect of the invention, the entire pump
can include, or even consist essentially of, polymer material(s),
optionally fiber-reinforced for the parts of the pump having a
mechanical function, such as the support. By way of non-limiting
example, the pump body may include, or even consist essentially of,
polyolefin, polycarbonate, or fluoropolymer such as PFA or PTFE.
The support may be made of polycarbonate, polyphenylene sulfide
(PPS) or polypropylene, possibly reinforced with glass fibers. The
membrane may include, or even consist essentially of, PFA, which
has a Young's modulus in a range of between 500 MPa and 600 MPa.
Such a pump including, or even consisting essentially of, polymer
material(s) can make it possible to limit the manufacturing cost
and the weight of the pump. Moreover, there may be no metal part in
contact with the fluid or fluids to move, which may be particularly
advantageous in the case of displacement of aggressive fluids that
tend to attack metal materials or of fluid susceptible to a
metallic contamination.
[0024] It will be appreciated that several known geometries of
membranes are compatible with the invention.
[0025] According to one embodiment, the membrane can be in the form
of a substantially parallelepiped strip retained in a circulation
space which is delimited by two, preferably rigid, walls disposed
facing the main surfaces of the membrane. An excitation force
substantially perpendicular to the mean plane of the membrane can
then be applied to an edge of the membrane which is situated on the
side of the entry orifice of the circulation space, such that the
deformation waves can be propagated towards an opposite edge of the
membrane which is situated on the side of the output orifice of the
circulation space.
[0026] According to another embodiment, the membrane can have a
tubular form, and can be retained in a tubular circulation space
with rigid walls. A distribution of symmetric radial excitation
forces can then be applied to one end of the tubular membrane which
is situated on the side of the entry orifice of the circulation
space, such that the deformation waves can be propagated towards
the opposite end of the membrane which is situated on the side of
the output orifice of the circulation space.
[0027] According to yet another embodiment, the membrane can be in
the form of a disc, or a portion of a disc, and retained in a
circulation space delimited by two, preferably rigid, walls which
are disposed facing the main surfaces of the membrane. An
excitation force substantially perpendicular to the mean plane of
the membrane can then be applied to a first end of the membrane
which is situated on the side of the entry orifice of the
circulation space, such that the deformation waves can be
propagated towards a second end of the membrane which is situated
on the side of the output orifice of the circulation space. An
advantage of this embodiment with discoidal geometry is that the
retention of the membrane in the circulation space can be
simplified, since the membrane is retained only at the level of its
outer peripheral edge.
[0028] According to a first variant of the embodiment with
discoidal geometry, the first end of the membrane which is situated
on the side of the entry orifice, to which the excitation force is
applied, can be a central edge of the membrane, whereas the second
end of the membrane which is situated on the side of the output
orifice can be an outer peripheral edge of the membrane. This
arrangement corresponds to a centrifugal configuration of the pump,
wherein the fluid circulates from the centre towards the periphery
of the membrane.
[0029] According to a second variant of the embodiment with
discoidal geometry, the first end of the membrane which is situated
on the side of the entry orifice, to which the excitation force is
applied, can be an outer peripheral edge of the membrane, whereas
the second end of the membrane which is situated on the side of the
output orifice can be a central edge of the membrane. This
arrangement corresponds to a centripetal configuration of the pump,
wherein the fluid circulates from the periphery towards the centre
of the membrane. This centripetal configuration can generate an
effect of concentration of the energy, from the periphery towards
the centre of the circulation space, thus making it possible to
obtain pressure gradients which are compatible with those required
in industrial applications. This centripetal configuration can also
make it possible to work with smaller amplitudes of excitation at
the level of the outer peripheral edge of the membrane, and thus to
limit the damage to fragile fluids.
[0030] In an embodiment, the pump body can include two rigid walls
opposite one another, which define between them the circulation
space. The membrane can be substantially in the form of a disc and
retained in the circulation space parallel to the rigid walls. The,
or each, entry orifice can then preferably open into the
circulation space in the vicinity of the periphery of the membrane,
whereas the, or each, output orifice can open into the circulation
space in the vicinity of a central area of the membrane, which
corresponds to the centripetal configuration.
[0031] Irrespective of the geometry of the membrane, the membrane
and/or the support can advantageously comprise orifices, such that
the fluid can pass on both sides of the membrane in the circulation
space. It can thus be possible to exploit the entire volume of the
pump body to transfer the mixing energy. In particular, in the
embodiment with discoidal geometry, the membrane and/or the support
can comprise at least one peripheral orifice and at least one
central orifice.
[0032] According to one embodiment, the pump body can comprise a
first flange and a second flange forming two, preferably rigid,
walls opposite one another which define between them the
circulation space, the first flange comprising the entry and output
orifices of the circulation space. The second flange can comprise a
drainage orifice of the pump.
[0033] The transverse cross section of the circulation space of the
pump according to the invention, taken perpendicularly to the
direction of circulation, can be globally constant, increasing or
decreasing from the entry orifice of the circulation space towards
the output orifice of the circulation space. In particular, in the
case of a membrane with discoidal geometry, the thickness of the
circulation space can be globally constant, increasing or
decreasing from the periphery of the membrane towards a central
area of the membrane. A configuration in which the transverse cross
section of the circulation space is globally increasing from the
entry orifice towards the output orifice can make it possible to
ensure a substantial fluid delivery at the level of the output
orifice. A configuration in which the transverse cross section of
the circulation space is globally decreasing from the entry orifice
towards the output orifice can make it possible to assist the
propagation of waves from the end which is subjected to the
excitation force towards the other end of the membrane.
[0034] According to one aspect of the invention, the actuating
device can include at least one linear electromagnetic actuator
supplied with an alternating current. As a variant, the actuating
device can comprise at least one mechanical actuator, for example a
connecting rod-crank actuator, motorized by a variable speed gear
motor.
[0035] In an embodiment, the pump can include at least one
ferromagnetic element, which can be housed in the pump body and
which can form a movable part of the actuating device for vibrating
the membrane. A winding can then be provided around the pump body
so as to induce a displacement of the ferromagnetic element inside
the pump body. This configuration may allow for a completely
enclosed body pump.
[0036] According to one aspect, the pump can include at least one
fluid flow sensor at the outlet of the pump, which is connected in
feedback with the actuating device, so as to maintain a constant
fluid flow.
[0037] In an embodiment, a membrane pump according to an embodiment
of the invention can make it possible to control the fluid flow
rate by adjusting the amplitude and/or the frequency of vibration
of the membrane imposed by the actuating device.
[0038] A particular embodiment of the invention can also relate to
a fluid displacement apparatus comprising a high flow rate
distribution pump and a membrane pump as described above, wherein
the membrane pump is connected to the outlet of the distribution
pump. The provision of a membrane pump according to certain
embodiments of the invention at the outlet of a distribution pump
can make it possible to obtain a smooth flow of fluid, or to obtain
more precision on the amount of fluid delivered. It can also make
it possible to act as a proportional valve and to reduce the fluid
pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The characteristics and advantages of the invention will
become apparent from the following description of a pump according
to the invention, provided purely by way of example and with
reference to the attached drawings in which:
[0040] FIG. 1 includes a perspective view with partial cut-out of a
pump in accordance with an embodiment;
[0041] FIG. 2 includes a transverse cross section according to the
planes II-II in FIG. 1;
[0042] FIG. 3 includes a perspective view of the membrane of the
pump in FIGS. 1 and 2.
DETAILED DESCRIPTION
[0043] The following description in combination with the figures is
provided to assist in understanding the teachings disclosed herein.
The following discussion will focus on specific implementations and
embodiments of the teachings. This focus is provided to assist in
describing the teachings and should not be interpreted as a
limitation on the scope or applicability of the teachings. However,
other embodiments can be used based on the teachings as disclosed
in this application. Reference to ranges
[0044] The terms "comprises," "comprising," "includes,"
"including," "has," "having" or any other variation thereof, are
intended to cover a non-exclusive inclusion. For example, a method,
article, or apparatus that comprises a list of features is not
necessarily limited only to those features but may include other
features not expressly listed or inherent to such method, article,
or apparatus. Further, unless expressly stated to the contrary,
"or" refers to an inclusive-or and not to an exclusive-or. For
example, a condition A or B is satisfied by any one of the
following: A is true (or present) and B is false (or not present),
A is false (or not present) and B is true (or present), and both A
and B are true (or present).
[0045] Also, the use of "a" or "an" is employed to describe
elements and components described herein. This is done merely for
convenience and to give a general sense of the scope of the
invention. This description should be read to include one, at least
one, or the singular as also including the plural, or vice versa,
unless it is clear that it is meant otherwise. For example, when a
single item is described herein, more than one item may be used in
place of a single item. Similarly, where more than one item is
described herein, a single item may be substituted for that more
than one item.
[0046] Unless otherwise defined, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. The
materials, methods, and examples are illustrative only and not
intended to be limiting. To the extent not described herein, many
details regarding specific materials and processing acts are
conventional and may be found in textbooks and other sources within
the fluid pumping arts.
[0047] FIGS. 1 and 2 generally include a pump 1 having a pump body
3 which defines in its inner volume a circulation space 4 for fluid
flow. A deformable membrane 6 may be contained within the
circulation space 4 for the propulsion of fluid. The pump body 3
comprises two flanges, an upper flange 5 and a lower flange 7,
connected to each other at their periphery. In the assembled
configuration of the pump body 3, a rigid wall 51 of the upper
flange 5 is located opposite a rigid wall 71 of the lower flange 7,
so that the walls 51 and 71 define therebetween the circulation
space 4. As shown in FIG. 1, the circulation space 4 has a disk
shape similar to the membrane 6.
[0048] The wall 51 of the upper flange 5 may include a peripheral
orifice 52 and a central orifice 54, which form, respectively, a
fluid entry orifice in the circulation space 4 and a fluid outlet
orifice from the circulation space 4. Fluid may circulate in the
circulation space 4 in a radial centripetal direction A, from the
peripheral entry orifice 52 to the central outlet orifice 54. In
practice, tubes (not shown) for fluid supply can be connected to
the orifices 52 and 54.
[0049] According to embodiments of the invention, at least a
portion of the membrane 6 is made of a polymer material having a
Young's modulus in a range of between 100 MPa and 10 Gpa. For
example, in an embodiment the membrane 6 may include, or consist
essentially of, PEA. Flanges 5 and 7 may also be made of a polymer
material, such as for example polypropylene. In an embodiment, the
membrane 6 and the flanges 5 and 7 may be formed by molding, such
as by injection molding.
[0050] The membrane 6 has a median plane P and may be maintained
under tension in the circulation space 4 parallel to the direction
A. An outer peripheral end 61 of the membrane 6 may be fixed to a
rigid support 8. The support 8 may include a ring portion 80 and a
plurality of peripheral legs 81 distributed circumferentially,
projecting from the annular portion 80. The support 8 may be made
of a polymer material, such as for example, polycarbonate. The
support 8 may be obtained by molding a single piece, such as by
injection molding. In an embodiment, the membrane 6 may be
assembled with the support 8 by overmolding.
[0051] In an embodiment, the membrane 6 may have a central orifice
64 and the support 8 may include a plurality of peripheral orifices
82. Thus, fluid may circulate in the circulation space 4 on both
sides of the membrane 6. That is, fluid may circulate both in the
volume defined between the membrane 6 and the upper flange 5 and in
the volume defined between the membrane 6 and the lower flange
7.
[0052] As shown in FIGS. 1 and 2, the peripheral legs 81 of the
support 8 may project outwardly from the pump body 3 through holes
78 of the lower flange 7. In an embodiment, the support 8 has six
peripheral legs 81 that pass through six holes 78 of the lower
flange 7, Seals 2 may be provided in each hole 78. In an
embodiment, the seals 2 may be made of a fluoropolymer, such as
PTFE, and connected to the legs 81 of the support 8 by any suitable
arrangement, including by overmolding, welding, or
snap-fitting.
[0053] The peripheral legs 81 of the support 8 may be provided to
be coupled to an actuating device 9, which in an embodiment
comprises a plurality of electromagnetic linear actuators including
movable portions 91 that are adapted to be secured with the
peripheral legs 81, for example snapped into the interior of
peripheral legs 81.
[0054] When energized by an alternating current, each actuating
device produces a reciprocating translational displacement of a
movable part 91, which results from the occurrence of Laplace
forces within the actuating device. The moving parts 91 of the
actuating devices are then capable of imparting to the support 8 a
translational motion in a direction B substantially perpendicular
to the median plane P of the membrane 6. Thus, the actuation device
9 is able to generate in an alternative manner, at the outer
peripheral end 61 of the membrane 6, an excitation force F
substantially perpendicular to the median plane P of the membrane
6.
[0055] The material and dimensions of the support 8 may be chosen
such that the support 8 has sufficient stiffness to ensure that the
excitation force F applied to the peripheral end 61. of the
membrane 6 is substantially the same over the entire periphery of
the membrane, even if the actuators act discretely at the legs
81.
[0056] In an embodiment, to ensure good wave propagation from the
peripheral end 61 of the membrane 6 which is subjected to the force
F, towards the end of the membrane that defines the central opening
64, the membrane 6 has a thickness e decreasing from its peripheral
end 61 to its central orifice 64.
[0057] The pump 1 described above which, according to embodiments
of the invention, may include a membrane 6. The membrane 6 may be
made of PFA, which is a fluoropolymer having a Young's modulus in a
range of between 500 MPa and 600 MPa, making it possible to obtain
an effective displacement of fluids, both for small and large
volumes, and can be used to move mechanically and/or chemically
aggressive fluids, such as fluids used for the manufacture of
semiconductor components.
[0058] By replacing a membrane made of silicone elastomer with a
membrane including, or even consisting essentially of, PFA, the
fluid flow obtained with the membrane including, or even consisting
essentially of, PFA is of the same order as that obtained with the
membrane made of silicone elastomer. It has been observed that the
decrease in fluid flow of the pump with a membrane including, or
even consisting essentially of, PFA relative to the pump with a
membrane made of silicone elastomer is, for the same operating
frequency of the membrane, within a range of 15% maximum of the
fluid flow rate obtained with the membrane of silicone
elastomer.
[0059] These results can also be obtained when the membrane 6 has a
layered structure including, for example, a protective coating made
of a material with a polymer organic matrix having a Young's
modulus in a range of between 100 MPa and 10 GPa, such as in a
range of between 200 MPa and 2 GPa, for example PRA; and at least
one inner layer which, in the assembled configuration of the pump,
is protected by the protective coating from a fluid flowing in the
circulation space 4, where the inner layer may consist of another
material than the material of the protective coating.
[0060] The inner layer of the membrane may be made of a polymer
material having a Young's modulus much lower than 100 MPa, such as
a silicone or polyurethane elastomer.
[0061] Advantageously, a pump according to certain embodiments of
the invention may reduce the shear stresses generated in the
circulated fluid, which may avoid damage to the components. A pump
according to certain embodiments of the invention is thus
applicable to moving all kinds of fluids, including fluids which
are fragile or charged with particles, in particular biological or
pharmaceutical fluids. A pump according to certain embodiments of
the invention is also well suited for mixing of non-Newtonian
fluids, the shearing of which is to be controlled, for example for
mixing of shear-thinning or shear-thickening fluids, or for mixing
of fluids which can clot irreversibly under the shearing effect. In
addition, with a pump according to certain embodiments of the
invention, the risks of leakage and contamination are limited,
thanks to the absence of mechanical bearings associated with a
rotating member. A pump according to certain embodiments of the
invention also has a reduced size, particularly it is flattened
compared to a centrifugal pump thanks to the lower size of the
membrane with respect to a turbine.
[0062] The invention is not limited to the examples described and
illustrated in the Figures.
[0063] In particular, as mentioned above, the membrane of a pump
according to certain embodiments of the invention can be made of
any material with a polymer organic matrix other than PFA, having a
Young's modulus in a range of between 100 MPa and 10 GPa, such as
in a range of between 200 MPa and 2 GPa, particularly FEP or PTFE.
The membrane pump according to certain embodiments of the invention
may also have a layered structure as mentioned above, comprising a
protective coating made of a material with a polymer organic matrix
having a Young's modulus in a range of between 100 MPa and 10 GPa,
such as in a range of between 200 MPa and 2 GPa, and a core layer
formed by at least one inner layer which may be made of another
material than the material constituting the protective coating,
especially a polymer material having a Young's modulus much lower
than 100 MPa, so as to increase the elasticity of the membrane.
[0064] The membrane of the pump may also have a geometry other than
discoidal. Inn particular, the membrane may have a blade or tubular
geometry. In addition, only one side of the membrane may be used to
move the fluid, which would be the case for example in the
embodiment described above in the absence of the central opening 64
and/or peripheral holes 82 that allow fluid passage on either side
of the membrane. Furthermore, in the above embodiment, the pump may
comprise a plurality of entry orifices 52, distributed
circumferentially around the periphery of the pump body, and a
central output orifice 54. The pump may also include a check valve,
for example at the outlet 54, so as to ensure a function of
metering pump.
[0065] According to another variant of the previous embodiment, the
support 8 and the membrane 6 or the protective coating of the
membrane 6 can be made of a same material with a polymer organic
matrix having a modulus Young in a range of between 100 MPa and 10
GPa, such as in a range of between 200 MPa and 2 GPa. The support
may be integral with the membrane, and formed in one piece
therewith, particularly by molding. Regardless of the relative
configuration of the membrane and the support, in one piece or two
separate pieces, the holes for letting the fluid pass on both sides
of the membrane in the circulation space, referenced 64 and 82 in
the previous embodiment, may be provided either on the membrane or
on the support.
[0066] In an embodiment, actuating devices other than the linear
electromagnetic actuators described above can be used in the
context of the invention. In particular, the structure of the
electromagnetic actuators can be modified such that a coil is
provided around the pump body so as to induce a displacement of the
movable part of each actuator inside the pump body. This
configuration allows for a completely enclosed pump body without
any portion 81 passing towards the exterior of the pump body, which
is particularly advantageous for sealing. Alternatively, as already
mentioned, the electromagnetic actuators can also be replaced by
other types of actuators, such as mechanical actuators.
[0067] It is also possible for a single pump to comprise several
membranes arranged in parallel so as to undulate together, in the
circulation space, under the effect of the excitation force F and
arranged to force a flow of fluid through the circulation space
from the entry orifice of the circulation space towards the outlet
orifice of the circulation space.
[0068] Many different aspects and embodiments are possible. Some of
those aspects and embodiments are described below. After reading
this specification, skilled artisans will appreciate that those
aspects and embodiments are illustrative and do not limit the scope
of the present invention. Embodiments may be in accordance with any
one or more of the items as listed below.
[0069] Item 1. A pump comprising a pump body which defines a
circulation space for circulation of fluid according to a direction
of circulation from an entry orifice of the circulation space to an
output orifice of the circulation space, the pump comprising:
[0070] a membrane which is retained in the circulation space
substantially parallel to the direction of circulation, [0071] an
actuating device which is adapted to vibrate the membrane, in
particular substantially perpendicular to the direction of
circulation, [0072] wherein either the membrane comprises a
protective coating made of a material having an polymer organic
matrix with a Young's modulus of between 100 MPa and 10 GPa,
preferably between 200 MPa and 2 GPa, or the membrane is made of a
material having a polymer organic matrix with a Young's modulus of
between 100 MPa and 10 GPa, preferably between 200 MPa and 2
GPa.
[0073] Item 2. The pump according to item 1, wherein the polymer
organic matrix of the membrane or of the protective coating of the
membrane is made of a fluoropolymer.
[0074] Item 3. The pump according to either one of items 1 or 2,
wherein each seal of the pump is made of a fluoropolymer.
[0075] Item 4. The pump according to any one of the preceding
items, wherein the pump comprises a support, which is connected to
an end of the membrane and at least a projecting part of which
passes in a sealed manner towards the exterior of the pump body,
the actuating device being configured to act on this projecting
part of the support, such as to generate in an alternating manner
at the end of the membrane an excitation force, preferably
substantially perpendicular to the direction of circulation.
[0076] Item 5. The pump according to according to item 4, wherein
the support is made of a same polymer material as the membrane or
the protective coating of the membrane.
[0077] Item 6. The pump according to any one of the preceding
items, wherein the entire pump is made of polymer material(s),
optionally fiber-reinforced.
[0078] Item 7. The pump according to any one of the preceding
items, wherein the pump body comprises two rigid walls opposite one
another, which define between them the circulation space, the
membrane being substantially in the form of a disc, and retained in
the circulation space substantially parallel to the rigid
walls.
[0079] Item 8. The pump according to item 7, wherein each entry
orifice opens into the circulation space in the vicinity of the
periphery of the membrane, whereas each output orifice opens into
the circulation space in the vicinity of a central area of the
membrane.
[0080] Item 9. The pump according to either one of items 7 or 8,
wherein the membrane and/or a support connected to an end of the
membrane comprise at least one peripheral orifice and at least one
central orifice.
[0081] Item 10. The pump according to any one of the preceding
items, wherein the pump body (3) comprises a first flange (5) and a
second flange (7) which form two walls (51, 71) facing one another
defining between them the circulation space (4), the first flange
(5) having the entry orifice (52) and the output orifice (54).
[0082] Item 11. The pump according to any one of the preceding
items, wherein the actuating device (9) comprises at least one
electromagnetic linear actuator powered by an alternating
current.
[0083] Item 12. The pump according to any one of the preceding
items, comprising at least one ferromagnetic element, which is
housed in the pump body and which forms a movable part of the
actuating device.
[0084] Item 13. The pump according to any one of the preceding
items, comprising at least one fluid flow sensor which is connected
in feedback with the actuating device.
[0085] Item 14. A fluid displacement apparatus comprising a high
flow rate distribution pump and a membrane pump according to any
one of the preceding items, wherein the membrane pump is connected
to the outlet of the distribution pump.
[0086] Item 15. A container-mixer comprising: [0087] a container
which is adapted to receive a fluid, wherein the container is made
of flexible material; and [0088] a pump according to any one of the
preceding items disposed in the container.
[0089] Item 16. A pump comprising: [0090] a pump body defining a
circulation space for circulation of fluid according to a direction
of circulation from an entry orifice of the circulation space to an
output orifice of the circulation space; [0091] a membrane retained
in the circulation space substantially parallel to the direction of
circulation; and [0092] an actuating device adapted to vibrate the
membrane in a direction substantially perpendicular to the
direction of circulation, [0093] wherein the membrane comprises a
material or a protective coating having a polymer organic matrix
with a Young's modulus in a range of between 100 MPa and 10
GPa.
[0094] Item 17. The pump according to item 16, wherein the polymer
organic matrix of the membrane or of the protective coating of the
membrane comprises a fluoropolymer.
[0095] Item 18. The pump according to item 16, wherein the pump
further comprises at least one seal, and wherein the at least one
seal comprises a fluoropolymer.
[0096] Item 19. The pump according to item 16, wherein the pump
further comprises: [0097] a support connected to an end of the
membrane, [0098] wherein a projecting part of the support passes in
a sealed manner towards the exterior of the pump body, and wherein
the actuating device is adapted to act on the projecting part of
the support to generate in an excitation force at the end of the
membrane.
[0099] Item 20. The pump according to item 19, wherein the support
comprises a polymer material, and wherein the polymer material of
the support is the same as a polymer material of the protective
coating of the membrane.
[0100] Item 21. The pump according to item 19, wherein at least one
of the membrane and the support comprises at least one peripheral
orifice and at least one central orifice.
[0101] Item 22. The pump according to item 16, wherein the pump
body comprises a polymer.
[0102] Item 23. The pump according to item 22, wherein the polymer
is fiber-reinforced.
[0103] Item 24. The pump according to item 16, wherein the pump
body comprises a first rigid wall and a second rigid wall opposite
one another and defining therebetween the circulation space.
[0104] Item 25. The pump according to item 24, wherein the membrane
comprises a disc, and wherein the membrane is retained in the
circulation space substantially parallel to the first and second
rigid walls.
[0105] Item 26. The pump according to item 16, wherein the entry
orifice opens into the circulation space in the vicinity of the
periphery of the membrane, and wherein the output orifice opens
into the circulation space in the vicinity of a central area of the
membrane.
[0106] Item 27. The pump according to item 16, wherein the pump
body further comprises a first flange defining a first wall and a
second flange defining a second wall, wherein the first and second
walls define between them the circulation space, and wherein the
first flange defines the entry orifice and the output orifice.
[0107] Item 28. The pump according to item 16, wherein the
actuating device comprises at least one electromagnetic linear
actuator powered by an alternating current.
[0108] Item 29. The pump according to item 16, further comprising
at least one ferromagnetic element coupled to the actuating
device.
[0109] Item 30. The pump according to item 16, further comprising
at least one fluid flow sensor connected with the actuating
device.
[0110] Item 31. The pump according to item 16, wherein the material
or the protective coating has a polymer organic matrix with a
Young's modulus in a range of between 200 MPa and 2 GPa.
[0111] Item 32. The pump according to item 16, wherein the pump her
comprises a check valve disposed at the output orifice.
[0112] Item 33. The pump according to item 16, wherein the membrane
has a discoidal geometry.
[0113] Item 34. A fluid displacement apparatus comprising a high
flow rate distribution pump and a membrane pump according to item
16, wherein the membrane pump is connected to an outlet of the
distribution pump.
[0114] Item 35. A container-mixer comprising: [0115] a container
adapted to receive a fluid, the container comprising a flexible
material; and [0116] a pump according to item 16 disposed in the
container.
[0117] Item 36. A pump comprising: [0118] a pump body defining a
circulation space for circulation of fluid according to a direction
of circulation from an entry orifice of the circulation space to an
output orifice of the circulation space; [0119] a membrane retained
in the circulation space substantially parallel to the direction of
circulation; and [0120] an actuating device adapted to vibrate the
membrane in a direction substantially perpendicular to the
direction of circulation, [0121] wherein the membrane comprises a
material or a protective coating having a polymer organic matrix
with a Young's modulus in a range of between 100 MPa and 10
GPa.
[0122] Item 37. The pump according to item 36, wherein the polymer
organic matrix of the membrane or of the protective coating of the
membrane comprises a fluoropolymer.
[0123] Item 38. The pump according to either one of the preceding
items, wherein the pump further comprises at least one seal, and
wherein the at least one seal comprises a fluoropolymer.
[0124] Item 39. The pump according to any one of the preceding
items, wherein the pump further comprises: [0125] a support
connected to an end of the membrane, [0126] wherein a projecting
part of the support passes in a sealed manner towards the exterior
of the pump body, and wherein the actuating device is adapted to
act on the projecting part of the support to generate in an
excitation force at the end of the membrane.
[0127] Item 40. The pump according to according to item 39, wherein
the support comprises a polymer material, and wherein the polymer
material of the support is the same as a polymer material of the
protective coating of the membrane.
[0128] Item 41. The pump according to item 39, wherein at least one
of the membrane and the support comprises at least one peripheral
orifice and at least one central orifice.
[0129] Item 42. The pump according to any one of the preceding
items, wherein the pump comprises a fiber-reinforced polymer.
[0130] Item 43. The pump according to any one of the preceding
items, wherein the pump body comprises a first rigid wall and a
second rigid wall opposite one another and defining therebetween
the circulation space, wherein the membrane comprises a disc, and
wherein the membrane is retained in the circulation space
substantially parallel to the first and second rigid walls.
[0131] Item 44. The pump according to item 43, wherein the entry
orifice opens into the circulation space in the vicinity of the
periphery of the membrane, and wherein the output orifice opens
into the circulation space in the vicinity of a central area of the
membrane.
[0132] Item 45. The pump according to any one of the preceding
items, wherein the pump body further comprises a first flange
defining a first wall and a second flange defining a second wall,
wherein the first and second walls define between them the
circulation space, and wherein the first flange defines the entry
orifice and the output orifice.
[0133] Item 46. The pump according to any one of the preceding
items, wherein the actuating device comprises at least one
electromagnetic linear actuator powered by an alternating
current.
[0134] Item 47. The pump according to any one of the preceding
items, further comprising at least one ferromagnetic element
coupled to the actuating device.
[0135] Item 48. The pump according to any one of the preceding
items, further comprising at least one fluid flow sensor connected
with the actuating device.
[0136] Item 49. A fluid displacement apparatus comprising a high
flow rate distribution pump and a membrane pump according to any
one of the preceding items, wherein the membrane pump is connected
to an outlet of the distribution pump.
[0137] Item 50. A container-mixer comprising: [0138] a container
adapted to receive a fluid, the container comprising a flexible
material; and [0139] a pump according to any one of the preceding
items disposed in the container.
[0140] Note that not all of the features described above are
required, that a portion of a specific feature may not be required,
and that one or more features may be provided in addition to those
described. Still further, the order in which features are described
is not necessarily the order in which the features are
installed.
[0141] Certain features are, for clarity, described herein in the
context of separate embodiments, may also be provided in
combination in a single embodiment. Conversely, various features
that are, for brevity, described in the context of a single
embodiment, may also be provided separately or in any
subcombinations.
[0142] Benefits, other advantages, and solutions to problems have
been described above with regard to specific embodiments. However,
the benefits, advantages, solutions to problems, and any feature(s)
that may cause any benefit, advantage, or solution to occur or
become more pronounced are not to be construed as a critical,
required, or essential feature of any or all the claims.
[0143] The specification and illustrations of the embodiments
described herein are intended to provide a general understanding of
the structure of the various embodiments. The specification and
illustrations are not intended to serve as an exhaustive and
comprehensive description of all of the elements and features of
apparatus and systems that use the structures or methods described
herein. Separate embodiments may also be provided in combination in
a single embodiment, and conversely, various features that are, for
brevity, described in the context of a single embodiment, may also
be provided separately or in any subcombination. Further, reference
to values stated in ranges includes each and every value within
that range. Many other embodiments may be apparent to skilled
artisans only after reading this specification. Other embodiments
may be used and derived from the disclosure, such that a structural
substitution, logical substitution, or any change may be made
without departing from the scope of the disclosure. Accordingly,
the disclosure is to be regarded as illustrative rather than
restrictive.
* * * * *