U.S. patent application number 10/573287 was filed with the patent office on 2007-05-10 for peristaltic pump.
Invention is credited to Rene Fassler, Stephan Michels, Daniel Saxer, Corinne Scharer.
Application Number | 20070104599 10/573287 |
Document ID | / |
Family ID | 34383944 |
Filed Date | 2007-05-10 |
United States Patent
Application |
20070104599 |
Kind Code |
A1 |
Michels; Stephan ; et
al. |
May 10, 2007 |
Peristaltic pump
Abstract
The invention relates to a peristaltic pump in which a case is
formed by a dimensionally stable supporting frame (1) and by a tube
reception device (2) formed thereon by clipping. A rotor (3)
provided with three rotatable transport rollers (33a, 33b, 33c).
Said tube reception device (2) is provided with a tube bearing body
(25) which forms a bed for the tubes on the internal surface and
comprises two legs (2a, 2b) on the ends thereof. The tube flexible
sections (43) are compresses by said transport rollers (33a, 33b,
33c) in order to ensure the peristaltic conveyance of a medium. The
two legs (2a, 2b) are elastically deformable in a radial direction
in order to be elastically adaptable on the supporting frame (1).
The bearing body (25) is substentially omega-shaped and provided
with uniform input and output areas which ensure a medium
continuous low-pulsed peristaltic conveyance. The inventive pump is
constructed in such a way that it is small-sized, comprises few
spare parts and is rapidly and easily mounted.
Inventors: |
Michels; Stephan; (Dinhard,
CH) ; Fassler; Rene; (Zurich, CH) ; Scharer;
Corinne; (Uster, CH) ; Saxer; Daniel; (Zurich,
CH) |
Correspondence
Address: |
Maginot Moore & Beck
Chase Tower Suite 3250
111 Monument Circle
Indianapolis
IN
46204
US
|
Family ID: |
34383944 |
Appl. No.: |
10/573287 |
Filed: |
June 25, 2004 |
PCT Filed: |
June 25, 2004 |
PCT NO: |
PCT/CH04/00390 |
371 Date: |
March 23, 2006 |
Current U.S.
Class: |
417/477.1 |
Current CPC
Class: |
F04B 43/1253 20130101;
F04B 43/1292 20130101 |
Class at
Publication: |
417/477.1 |
International
Class: |
F04B 43/12 20060101
F04B043/12 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 26, 2003 |
CH |
1635/03 |
Claims
1. Peristaltic pump, with a rotor (3) received in a housing, which
is provided with at least one rotatably supported conveyor roller
(33a, 33b, 33c), as well as with a tubing holder (2) for receiving
of at least one flexible tubing section (43) that is squeezable by
the conveyor roller (33a, 33b, 33c) for the peristaltically
conveying a medium, characterized in that the housing is
constituted by a dimensionally stable support frame (I) and by
tubing holder (2), whereby the tubing holder (2) is designed at
least partially elastically resilient such that it can be attached
to the support frame (1) in the sense of a snap-on connection, and
whereby the tubing holder (2) is fixed to the support frame (1) to
be dimensionally stable after the attachment.
2. Pump according to claim 1, characterized in that the tubing
holder (2) is provided with a tubing bed body member (25), having a
tubing bed at its inner side and two legs (2a, 2b) at its end, the
latter ones being resiliently elastic in radial direction.
3. Pump according to claim 2, characterized in that the tubing bed
body member (25) at least partially and coaxially enlaces the rotor
(3).
4. Pump according to claim 2, characterized in that the two legs
(2a, 2b) of the tubing bed body member (25) pass over from a
concave shape to a convex shape in a smooth transition in the
region of the particular leg end.
5. Pump according to claim 2, characterized in that the tubing bed
body member is designed essentially in the shape of an omega.
6. Pump according to claim 2, characterized in that the support
frame (1) is provided with cut-outs (13) and the legs (2a, 2b) of
the tubing bed body member (25) at their ends with notch elements
(22) for snapingly engaging the cutouts (13) of the support frame
(1).
7. Pump according to claim 6, characterized in that the notch
elements (22) are located at the outside of the legs (2a, 2b), and
that the support frame (1) is provided with a web (14) located
above the cut-outs (13), at the side facing the tubing bed body
member (25), for positively and/or non-positively supporting the
particular leg (2a, 2b) of the tubing bed body member (25) at the
outside.
8. Pump according to claim 2, characterized in that the tubing bed
body member (25) is designed such that its dimensional stability
and fixation at the support frame (1) is supported, in addition to
the elastically resilient inherent tenseness of the legs (2a, 2b),
by the mutal force action of the squeezed tubing section and the
squeezed tubing sections (43), respectively.
9. Pump according to claim 2 2, characterized in that the tubing
bed body member (25) is provided with a plurality of radially
and/or axially extending reinforcing ribs (23, 24).
10. Pump according to claim 2, characterized in that the inner side
of the tubing bed body member (25) is provided with a multitude of
groove-like recess (21) for receiving and guiding a plurality of
tubing sections (43).
11. Pump according to claim 9, characterized in that the particular
conveyor roller (33a, 33b, 33c) is in the shape of a barrel and
extends in axial directions over the groove-like recesses (21).
12. Pump according to claim 2, characterized in that the particular
tubing section is led into and out of the tubing bed body member
(25) in substantially tangential direction.
13. Pump according to claim 2, characterized in that the rotor (3)
is provided with at least two conveyor rollers (33a, 33b, 33c), and
that the tubing bed body member (25) coaxially enlaces the rotor
(3) by an amount of 360.degree. divided by the number of conveyor
rollers.
14. Pump according to claim 1, characterized in that the rotor (3)
is provided with three conveyor rollers (33a, 33b, 33c), and the
inlet portion (35) is offset around the axis of rotation of the
rotor (3) with regard to the outlet portion (36) by 210.degree. to
270.degree., preferably by approximately 240.degree..
15. Pump according to claim 3, characterized in that the two legs
(2a, 2b) of the tubing bed body member (25) pass over from a
concave shape to a convex shape in a smooth transition in the
region of the particular leg end.
Description
[0001] The invention refers to a peristaltic pump according to the
preamble of claim 1.
[0002] Peristaltic pumps of the kind discussed herein are
fundamentally known. They are used for conveying different liquid
and gaseous media.
[0003] From the EP 1 137 886, a roller pump for peristaltically
conveying of media is known, which is provided with a tube
cartridge. The tube cartridge is fixed to the roller pump by means
of a lockable cover. The conveying rollers are resiliently
supported by a rotation body member. As it is particularly evident
from FIG. 1 of this document, such a roller pump including the tube
cartridge has a relatively large length and, accordingly, requires
a lot of space.
[0004] From the WO 02/25112, a peristaltic pump is known, which is
provided with a multi-part housing in which a reduction gear box is
located. The pressure rollers for squeezing a flexible tube section
are integrated into the reduction gear box. Such a pump consists of
a multitude of components, is relatively expensive to manufacture
and requires a lot of time for assembling.
[0005] Finally, from the U.S. Pat. No. 5,857,843, a peristaltic
pump is known, which comprises a support frame on which the rotor
is replaceably supported. The support frame is provided with
latch-shaped notch elements, which serve for fixing a plate member
constituting the upper portion of the housing. The plate member is
concavely shaped at the inner side and serves to receive a flexible
tube section. Even if such a pump is of very simple design and can
be manufactured at low costs, it has, amongst else, the
disadvantage that only a comparatively small tube section and
circular arc section, respectively, is available for peristaltic
conveying. Moreover, the plate member appears to be relatively
unstable, particularly in transverse direction, what has a negative
influence on a constant conveying rate. Additionally, the mutual
force action of the squeezed tube can result in bending apart the
notch elements.
[0006] It is the object of the present invention to improve a pump
designed according to the preamble of claim 1 in such a way that it
is compact, that it can be manufactured at low costs, that it can
be assembled easily and quickly, and that it is very rigid in
assembled form and shows high shape constancy.
[0007] This object is met with a pump which comprises the
characteristics listed in the characterizing portion of claim
1.
[0008] Advantageous further developments of the peristaltic pump
are defined in the dependent claims 2 to 14.
[0009] In the following, a preferred embodiment of the invention is
further explained by means of drawings. Shown in these drawings is
in:
[0010] FIG. 1 an exploded view of the peristaltic pump;
[0011] FIG. 2 the assembled pump according to FIG. 1 in a first
cross sectional view; and
[0012] FIG. 3 the assembled pump according to FIG. 1 in a further
cross sectional view.
[0013] FIG. 1 shows a six channel peristaltic pump in an exploded
view. Substantially, the pump consists of a support frame 1, a
tubing holder 2, a rotor 3 and a connecting element 4 having six
tubing sections 43 located thereon. Also evident is a gear wheel 5
for coupling to a not shown driving motor.
[0014] The support frame 1, designed to be dimensionally stable,
constitutes, together with the tubing holder 2, the real housing of
the pump. For rotatably supporting the rotor 3, the support frame 1
is provided with two bearing sleeves 11. The two front faces of the
support frame 1 are constituted by panels 12, which are provided
with slots 15a, 15b for fixing the support frame 1 and the entire
pump, respectively. Finally, the support frame 1 is provided with
several slot-like cut-outs 13 on both sides, in which notch
elements 22 of the tubing holder 2 are clampingly fixable, as will
be described further in the following.
[0015] The tubing holder 2 comprises a tubing bed body member 25,
which is designed essentially in the shape of an Omega and which
extends at the inner side in the shape of a circular arc coaxial to
the axis of rotation of the rotor 3 over an angle of appr.
130.degree. to constitute a tubing bed. The expression "in the
shape of an omega" means in the present case that the tubing bed
body member 25 has substantially the shape of a capital omega
(.OMEGA.). In the end region, the tubing bed body member 25
presents two legs 2a, 2b which pass over from a concave shape to a
convex shape in a smooth transition. The tubing bed is divided into
six sections by means of groove-like recesses 21 which serve to
receive the flexible tube sections. In place of the groove-like
recesses 21 for constituting six sections, also a tubing mat,
consisting of six tubes connected to each other, could be used. In
this case, the tubing bed body member 25 could be provided with a
substantially smooth inner side. The two legs 2a, 2b of the tubing
bed body member 25 are provided, on the outer side, with notch
elements 22 by means of which the tubing holder 2 is fixable to the
slot-like cut-outs 13 of the support frame 1. The outer side of the
tubing bed body member 25 is provided with radially extending
reinforcing ribs 23 as well as with axially extending reinforcing
ribs 24. The radially extending reinforcing ribs 23 extend along
appr. 180.degree. of the outer side of the tubing bed body member
25. In any case, the tubing holder 2 is dimensioned such that the
ends of the two legs 2a, 2b of the tubing bed body member 25 are
resiliently flexible in radial direction and make possible a quick
fixing of the tubing holder 2 to the support frame 1 in the sense
of a snap-on connection.
[0016] The rotor 3 consists of a rotor body 31, provided with a
central axis 32 which is inserted into the bearing sleeves 11 of
the support frame 1. Three conveying rollers 33, designed in the
shape of barrels, are rotatably supported on the rotor body 31.
Preferably, the rotor body 3 is manufactured of plastic material,
while the central axis 32 as well as the conveying rollers 33
preferably consist of metal.
[0017] The connecting element 4 consists of a base element 41, to
which are fixed twelve pipe sections 42. Attached to the upper
portions of these pipe sections 42 are a total of six flexible
tubing sections 43, which rest on the inner side of the tubing bed
body member 25, once the pump is assembled, and which are
squeezable by the conveying rollers 33 for the peristaltic
conveying of a medium. It is understood that the design of the
inlet and the outlet section is not limited to a six channel pump,
but the number of the channels is substantially arbitrarily
variable.
[0018] The assembly of the shown components to a pump can be
accomplished with a few simple steps; first, the particular tubing
sections 43 are attached to the connecting element 4 and then, the
rotor 3 is transversely moved into the tubing sections 43 forming
loops. Thereafter, the tubing holder 2 is U-shapely positioned and
the rotor 3, together with the connecting element 4 and the tubing
sections 43 attached thereto are slid in from the top.
Subsequently, the support frame 1 is positioned upright and a
pressure is applied, such that the axis 32 of the rotor 3 as well
as the notch elements 22 snap in. Finally, the connecting element 4
is fixed to the support frame 1. In the embodiment shown here, the
connecting element 4 is fixed by means of screws. Alternatively, a
snap-on connection can be provided for fixing the connecting
element 4, which ensures a quick connection of the connecting
element 4 to the support frame 1. The entire assembly of the pump
can be performed, without the use of tools, from one side, which
constitutes an advantage in the case of an automatic
manufacture.
[0019] FIG. 2 shows a first cross sectional view of the assembled
pump. In this view, particularly the rotor body 31 together with
the three conveyor rolls 33a, 33b, 33c rotatably attached thereto
and squeezing the particular tubing section 43 in a rolling motion,
the tubing holder 2 with the omega-shaped tubing bed body member 25
as well as the radial and axial reinforcing ribs 23, 24 are
evident. The reinforcing ribs 23, 24 ensure that the tubing holder
is dimensionally stable and does not deform in operation under the
load of the conveyor rollers 33a, 33b, 33c. Due to the omega shaped
design of the tubing bed body member 25 with "soft" inlet portion
and outlet portion, a continuous substantially pulsation free
conveying of the particular medium is ensured. A further advantage
of the soft inlet and outlet portions is the reduction of torque
peaks which, otherwise, would load the motor and the gear box.
Assuming a sense of rotation D in counterclockwise direction, the
region designated by reference numeral 35 constitutes the inlet
portion, while the region designated by reference numeral 36
constitutes the outlet portion of the pump. The pump can be
operated both in clockwise direction and in counterclockwise
direction.
[0020] A soft and continuous inlet portion and outlet portion means
that both the inlet portion 35 and the outlet portion 36 are
designed such that the tubing cross section relevant for conveying
is continuously decreased and increased, respectively, by the
conveying roller 33a, 33c rolling along the particular flexible
tubing portion 43. In this connection, it is important that the
tubing bed body member 25 is accurately manufactured and that it
exhibits a high dimensional stability in operation such that the
predetermined distances between conveying roller 33a, 33b, 33c and
tubing bed body member 25 are maintained.
[0021] Besides the already mentioned advantage, further advantages
result from a continuous inlet portion and outlet portion; for
example, the torque fluctuations emerging from the rotation of the
rotor 3 are minimized. This is additionally favored by the facts
that the rotor 3 is provided with three conveying rollers 33a, 33b,
33c and that the inlet portion 35 is offset around the axis of
rotation of the rotor 3 by about 240.degree. relative to the outlet
portion 36, such that the first conveyor roller 33a is located
approximately in the middle of the inlet portion 35 when the third
conveyor roller 33c is located approximately in the middle of the
outlet portion 36. By means of the design shown in the drawings,
moreover, a high efficiency is realized and the mechanical load on
the tubing sections 43 is reduced, thus increasing their service
life. Since the pump is designed symmetrically, it can be operated
bi-directionally, i.e. in both senses of rotation. Additionally, as
the view shown in FIG. 2 exhibits, that the particular tubing
section 43 is not fully squeezed in the inlet portion 35 and in the
outlet portion 36, while it is fully squeezed after the inlet
portion 35 by the corresponding conveyor roller 33b to enable a
peristaltic conveying of the particular medium. A pump designed in
such a way is also particularly suitable for conveying fluid media
in a way gentle to cells, for example blood, because the blood
corpuscles are prevented from damage by the particular design of
the inlet and outlet portions 35, 36.
[0022] The design of the tubing holder 2 with a dimensionally
stable tubing bed body member 25 and with elastically resilient
legs 2a, 2b ensures a very quick and simple assembling, i.e. by
simply clicking in the tubing holder 2 into the support frame. Even
if the legs 2a, 2b have to be elastically resilient for assembly,
the tubing bed body member 25 has to maintain its dimensional
stability and a precise geometry. This goal is met, amongst else,
by the fact that the elastically resilient parts are positioned and
stiffened by means of an outer positive fitting support on the
support frame 1.
[0023] From FIG. 3, showing a cross sectional view of the assembled
pump taken between two tubing sections 43, particularly the
clamping fixation of the tubing bed body member 25 to the support
frame is evident. The notch elements 22 located at the outside of
the tubing bed body member 25 engage the slot-shaped cut-outs 13 of
the support frame 1. Moreover, the notch elements 22 positively
engage an upper web 14 of the support frame, delimiting the
slot-shaped cut-outs 13. In order to ensure a high stiffness in the
flexible region of the tubing bed body member 25 fixed to the
support frame 1, the legs 2a, 2b of the tubing bed body member 25
are positively supported at the outside by the web 14 of the
support frame 1. This design particularly also ensures a precise
observation of the optimized distances between the conveyor rollers
33a, 33b, 33c and the inside of the tubing bed body member 25.
[0024] The individual elastic tubing sections 43 additionally
support the fixing of the tubing bed body member 25 at the support
frame 1, since the conveyor rollers 33a, 33b, 33c of the rotor 3
load the tubing bed body member 25 in radial direction via the
tubing sections 43, such that the fixation thereof to the support
frame 1 is additionally supported.
[0025] The connecting element 4 is designed such and matched to the
tubing holder 2 and to the rotor 3 such that the individual tubing
section 43 is led essentially in tangential direction into the
tubing bed body member 25 of the tubing holder 2 and also led out
there from.
[0026] Even if, in the foregoing, reference has made to the
embodiment shown in the drawings of a pump with three conveyor
rollers, it is understood that the number of conveyor rollers can
be practically arbitrarily varied as long as one stays within the
scope of the present invention defined in the claims. Thereby, the
tubing bed body member 25 has to enlace the rotor 3, depending on
the number of conveyor rollers, to such a degree that always at
least one conveyor roller 33a, 33b, 33c is active, i.e. engages the
particular tubing section and squeezes it. The minimal enlacement
and the minimum angle of enlacement, respectively, can be
calculated as follows: Enlacement=360.degree./number of conveyor
rollers.
[0027] In the case of using such a pump for higher pressure,
moreover, it can be advantageous to have always two conveyor
rollers engage the flexible tubing section. In this case, the
enlacement can be calculated by using the following formula:
Enlacement=2.times.360.degree./number of conveyor rollers.
[0028] The calculated enlacement is to be understood as a minimal
amount of enlacement. Preferably, the enlacement is chosen about
10.degree. higher than the angle of enlacement calculated by means
of the foregoing formula. The expression "enlacement" shall be
understood as that part of the tubing bed that coaxially surrounds
the rotor.
[0029] In recapitulation, the following advantages of a peristaltic
pump designed according to the invention may be noticed: [0030] It
is of simple design and consists of only a few parts; [0031] It can
be assembled from one side and, thus, is suitable for automatic
manufacturing; [0032] It can be assembled quickly and without
tools; [0033] It shows a high dimensional stability (stiffness)
after having been assembled; [0034] It can be manufactured at low
costs; [0035] It is compact and light; [0036] It can be designed as
one channel or multiple channel pump; [0037] It is suitable for
conveying for example blood, gently conveying the blood cells;
[0038] It can be operated bi-directionally and universally used;
[0039] It reduces pulsation, torque peaks, is resistant to wear-out
and, thereby, has a higher efficiency.
* * * * *