U.S. patent application number 14/050517 was filed with the patent office on 2014-02-06 for peristaltic pump tubing with stopper and cooperative roller assembly housing having no moving parts.
The applicant listed for this patent is JEFFREY A. KLEIN. Invention is credited to JEFFREY A. KLEIN.
Application Number | 20140037479 14/050517 |
Document ID | / |
Family ID | 42540564 |
Filed Date | 2014-02-06 |
United States Patent
Application |
20140037479 |
Kind Code |
A1 |
KLEIN; JEFFREY A. |
February 6, 2014 |
PERISTALTIC PUMP TUBING WITH STOPPER AND COOPERATIVE ROLLER
ASSEMBLY HOUSING HAVING NO MOVING PARTS
Abstract
A peristaltic pump system includes elastomeric pump tubing and a
roller pump. The pump tubing has a pumping segment and an inlet
segment. The inlet segment has an inlet segment outer diameter. The
pumping segment has a pumping segment outer diameter less than the
inlet segment outer diameter. The roller pump has a roller assembly
and a roller assembly housing. The roller assembly is disposed
within the roller assembly housing and engaged with the pumping
segment within the roller assembly housing. The roller assembly
housing has an inlet gap formed through the roller assembly
housing. The inlet gap defines an inlet gap inner diameter smaller
than the pumping segment outer diameter. The inlet gap is adapted
to frictionally receive the inlet segment for aligning the pump
tubing with a roller assembly and mitigate longitudinal movement of
the pump tubing into the roller assembly housing.
Inventors: |
KLEIN; JEFFREY A.; (SAN JUAN
CAPISTRANO, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KLEIN; JEFFREY A. |
SAN JUAN CAPISTRANO |
CA |
US |
|
|
Family ID: |
42540564 |
Appl. No.: |
14/050517 |
Filed: |
October 10, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13346937 |
Jan 10, 2012 |
8579612 |
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14050517 |
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12539984 |
Aug 12, 2009 |
8118572 |
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13346937 |
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61150997 |
Feb 9, 2009 |
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Current U.S.
Class: |
417/476 |
Current CPC
Class: |
F04B 43/1238 20130101;
F04B 43/1261 20130101; F04B 43/1253 20130101; F04B 43/1223
20130101 |
Class at
Publication: |
417/476 |
International
Class: |
F04B 43/12 20060101
F04B043/12 |
Claims
1. A tubing for a peristaltic pump system having an inlet gap
defining an inlet gap inner diameter, the tubing comprising: an
elongate body having a round exterior surface, the elongate having
a lumen extending between opposed ends of the elongate body for
delivering the fluid, the elongate body being fabricated from an
elastomeric material, the elongate body having a pumping segment
and an inlet segment, the inlet segment having an inlet segment
outer diameter larger than the inlet gap inner diameter, the
pumping segment having a pumping segment outer diameter less than
the inlet segment outer diameter.
2. The tubing of claim 1 wherein the inlet segment has a constant
wall thickness along a length of the pumping segment.
3. The tubing of claim 1 wherein the pumping segment has a varying
wall thickness along a length of the pumping segment.
4. The tubing of claim 1 wherein the inlet segment outer diameter
is constant along a length of the pumping segment.
5. The tubing of claim 1 wherein the pumping segment outer diameter
varies along a length of the pumping segment.
6. The tubing of claim 1 wherein the pump tubing further has an
outlet segment with the pumping segment disposed between the inlet
segment and the outlet segment, the outlet segment is engaged with
the pumping segment
7. The tubing of claim 6 wherein the outlet segment has an outlet
segment outer diameter that is constant along a length of the
outlet segment.
8. The tubing of claim 6 wherein the outlet segment has an outlet
segment outer diameter that is the same as the pumping segment
outer diameter.
9. The tubing of claim 6 wherein the inlet segment has a wide
portion and a narrow portion with the wide portion disposed between
the narrow portion and the pumping segment, the inlet segment outer
diameter is disposed at the wide portion.
10. The tubing of claim 9 wherein an outer diameter of the narrow
portion is less than the inlet segment outer diameter.
11. The tubing of claim 10 wherein the outer diameter of the narrow
portion is the same as the outer diameter of the outlet
segment.
12. The tubing of claim 9 wherein a wall thickness of the wide
portion is greater than a wall thickness of the pumping
section.
13. The tubing of claim 1 wherein the inlet segment includes a
stopper ring disposed circumferentially about the tubing, the
stopper ring defines the inlet segment outer diameter.
14. The tubing of claim 13 wherein the stopper ring is
torus-shaped.
15. The tubing of claim 1 wherein the inlet segment includes a
semi-tubular segment disposed circumferentially about the tubing,
the semi-tubular segment defines the inlet segment outer
diameter.
16. The tubing of claim 1 wherein the pumping segment and the inlet
segment are formed of a single continuous piece of material.
17. A peristaltic pump system comprising: an elongate body having a
round exterior surface, the elongate having a lumen extending
between opposed ends of the elongate body for delivering the fluid,
the elongate body being fabricated from an elastomeric material,
the elongate body having a pumping segment and an inlet segment,
the inlet segment having an inlet segment outer diameter, the
pumping segment having a pumping segment outer diameter less than
the inlet segment outer diameter; and a roller pump having a roller
assembly and a roller assembly housing, the roller assembly being
disposed within the roller assembly housing and engaged with the
pumping segment within the roller assembly housing, the roller
assembly housing having an inlet gap formed through the roller
assembly housing, the inlet gap defining an inlet gap inner
diameter smaller than the pumping segment outer diameter, the inlet
gap being adapted to frictionally receive the inlet segment for
aligning the pump tubing with a roller assembly and mitigate
longitudinal movement of the pump tubing into the roller assembly
housing.
18. The system of claim 17 wherein the elongate body has a constant
wall thickness.
19. The system of claim 17 wherein the elongate body has a varying
wall thickness.
20. The system of claim 17 further comprising a stopper disposed
around the inlet segment wherein the stopper defines the inlet
segment outer diameter.
21. The system of claim 20 wherein the stopper is permanently
attached to the elongate body.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This non-provisional patent application claims the benefit
of U.S. Provisional Patent Application Ser. No. 61/150,997, filed
on Feb. 9, 2009, entitled "PERISTALTIC PUMP TUBING WITH STOPPER AND
COOPERATIVE ROLLER ASSEMBLY HOUSING HAVING NO MOVING PARTS", the
entire contents of which are incorporated herein by reference.
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable
BACKGROUND
[0003] This invention relates to peristaltic pumps, and more
particularly to safety and use improvements thereto.
[0004] A peristaltic pump consists of two principal component
parts, the tubing and pumphead assembly. These parts must be
mutually compatible in order for the peristaltic pump to be
functional. A peristaltic pump is a mechanical pump in which
pressure is provided by the movement of a constriction along a
tube, as in biological peristalsis. The constriction or pumping
action is usually provided by the movement of one or more rollers
rotatably mounted on a fixture which in turn rotates on an axis.
The movement of the rollers along a segment of the tube within the
pump raceway propels fluid through the tubing. There are several
interrelated factors that determine the pumping rate including the
dimensions and elastic quality of the tubing, as well as the rate
of compression applied by the pump rollers. The pump tubing is
placed into the raceway and traditionally fixed by means of clamps,
flanges or fixtures. Synonyms for peristaltic pump are roller pump,
tube pump, and hose pump.
[0005] The rate of fluid flow produced by a peristaltic pump is a
function of 1) the angular velocity of the roller assembly and 2)
the volume of fluid contained within the tubing delimited by
constrictions produced by two consecutive rollers. An increase the
inside diameter of the pump tubing within the pump raceway will
increase the volume of fluid pumped with each cyclic compression of
the tubing. Traditional peristaltic roller tubing includes an inlet
end, a central pumping segment which interacts with the rollers,
and an outlet end. An example of a peristaltic pump used for
tumescent infiltration is the Klein Pump (HK Surgical, Inc, US
Patent Publication No. 2004/0213685, filed October 2004 to
Klein).
[0006] The overall functional efficacy of a peristaltic pump system
depends on a combination of both the pump's roller assembly and the
pump tubing. Pump tubing is at least as important as the pump motor
and roller housing in terms of overall performance and
reliability.
[0007] Tumescent Local Anesthesia (TLA): is a very dilute solution
of lidocaine (.ltoreq.1 gram per liter) and epinephrine (.ltoreq.1
milligram per liter) with sodium bicarbonate (10 milliequivalents
per liter) in a crystalloid solution such as physiologic saline or
lactated Ringer's solution. Tumescent liposuction is surgical
technique for doing liposuction totally by local anesthesia using
tumescent local anesthesia. Tumescent liposuction using TLA is far
safer than liposuction performed under general anesthesia.
Tumescent or tumescence refers to the state of being swollen and
firm. Tumescent liposuction can involve the infiltration of several
liters of tumescent local anesthesia into the targeted areas of
subcutaneous fat. In addition to large volume liposuction totally
by local anesthesia, surgical applications of TLA include a growing
list of diverse therapeutic procedures. For example, in patients
with symptomatic varicosity of a greater saphenous vein, endovenous
laser ablation (EVLA) cannot be safely performed without tumescent
local anesthesia infiltrated into the peri-venous compartment of
the greater saphenous vein. Because the tumescent fluid acts as a
heat sink as well as a local anesthetic, TLA protects nerves and
arteries anatomically adjacent to the saphenous vein compartment
from heat trauma. TLA is an essential aspect of endovenous laser
ablation of the greater saphenous vein. There is a growing list of
complex therapeutic (not cosmetic) surgical procedures which are
now accomplished totally by local anesthesia using TLA, thereby
avoiding the risks of general anesthesia. For example, in elderly
patients whose cardiopulmonary status makes them poor candidates
for the use of general anesthesia, TLA is now employed for
mastectomy totally by local anesthesia (Carlson G W. Total
mastectomy under local anesthesia: the tumescent technique. Breast
J. 11:100-2, 2005), and arterial surgery for subclavian steal
syndrome totally by local anesthesia (Mizukami T, Hamamoto M.
Tumescent local anesthesia for a revascularization of a coronary
subclavian steal syndrome. Ann Thorac Cardiovasc Surg. 13:352-4,
2007). In all of these clinical applications of TLA surgeons use a
peristaltic pump to accomplish the infiltration of tumescent local
anesthesia. In order to avoid surgical site infections (SSI) it is
essential that the peristaltic tubing be sterile and disposable
when used in surgical settings.
[0008] Peristaltic pumps typically employ a mechanical system for
holding the tube securely in place during roller rotation which
consists of several moving parts such as clamps, attachment
flanges, connection brackets, or special fixtures that attach to
the metal, plastic or glass connectors that join sequentially
connected segments of tubing and retain the tubing in a fixed
position with respect to the roller assembly housing. Some pump
designs employ a clamping mechanism designed to squeeze the tube
and hold it in place by virtue of a crimping deformation of the
tube. There is need for a simplified roller assembly housing design
for securing a peristaltic tube within the roller assembly housing
which has no moving parts and only two parts exclusive of the
roller assembly, and protects fingers of personnel against injury
and protects the roller assembly from damage due to encounters with
extraneous or foreign objects.
BRIEF SUMMARY
[0009] An aspect of the invention relates to peristaltic pumps, and
more specifically to peristaltic roller pumps having means to
simplify and facilitate loading and unloading of tubing in a safe
manner. The present invention consists of two mutually dependent
innovations related to the tubing and to roller assembly housings
of peristaltic pumps. The simplified design of the pump tubing with
stopper element allows the tubing to be automatically secured
within the roller assembly housing and to concomitantly be
precisely aligned with the pump rollers. The simplified design of
the roller assembly housing has only two parts and no moving parts
yet it automatically aligns the novel pump tubing with respect to
the rollers, holds the tubing without clamps or connecting members.
This may also tend to prevent both injury due to finger
entanglement during the tube insertion process and damage to the
rollers during pump operation.
[0010] A peristaltic pump system includes elastomeric pump tubing
and a roller pump. The pump tubing has a pumping segment and an
inlet segment. The inlet segment has an inlet segment outer
diameter. The pumping segment has a pumping segment outer diameter
less than the inlet segment outer diameter. The roller pump has a
roller assembly and a roller assembly housing. The roller assembly
is disposed within the roller assembly housing and engaged with the
pumping segment within the roller assembly housing. The roller
assembly housing has an inlet gap formed through the roller
assembly housing. The inlet gap defines an inlet gap inner diameter
smaller than the pumping segment outer diameter. The inlet gap is
adapted to frictionally receive the inlet segment for aligning the
pump tubing with a roller assembly and mitigate longitudinal
movement of the pump tubing into the roller assembly housing.
[0011] According to various embodiments, the inlet segment may have
a constant wall thickness along a length of the pumping segment.
The pumping segment may have a varying wall thickness along a
length of the pumping segment. The inlet segment outer diameter may
be constant along a length of the pumping segment. The pumping
segment outer diameter may vary along a length of the pumping
segment. The pump tubing may further have an outlet segment with
the pumping segment disposed between the inlet segment and the
outlet segment, the outlet segment is engaged with the pumping
segment. The outlet segment may have an outlet segment outer
diameter that is constant along a length of the outlet segment. The
outlet segment may have an outlet segment outer diameter that is
the same as the pumping segment outer diameter. The inlet segment
may have a wide portion and a narrow portion with the wide portion
disposed between the narrow portion and the pumping segment. The
inlet segment outer diameter may be disposed at the wide portion.
An outer diameter of the narrow portion may be less than the inlet
segment outer diameter. The outer diameter of the narrow portion
may be the same as the outer diameter of the outlet segment. A wall
thickness of the wide portion may be greater than a wall thickness
of the pumping section. The inlet segment may include a stopper
ring disposed circumferentially about the tubing. The stopper ring
defines the inlet segment outer diameter. The stopper ring may be
torus-shaped. The inlet segment may include a semi-tubular segment
disposed circumferentially about the tubing. The semi-tubular
segment defines the inlet segment outer diameter. The pumping
segment and the inlet segment may be formed of a single continuous
piece of material.
[0012] The tubing may be a single use, sterile, disposable plastic
tubing having medical applications as well as other commercial,
industrial, laboratory and clinical applications.
[0013] In one embodiment, the tubing can be extruded as a single
component with an integrated stopper element thereby eliminating
the multiple component parts. In another embodiment the pump tubing
can have two functional pumping segments with different inside
diameters (ID) such that the larger ID can be used to pump large
volumes at a relatively high rate and the smaller ID can be used to
pump relatively small volumes of fluid slowly with precision and
finesse.
[0014] An aspect of the invention discloses a simplified
peristaltic roller pump system consisting of interrelated novel
pump tubing and novel roller assembly housing. A peristaltic roller
pump consists of two distinct and essential elements, pump tubing
and pumphead assembly, which together are sufficient for pumping
action.
[0015] The present inventive pump tubing may consist of a length of
elastomeric tubing having an inlet segment, a stopper segment, a
pumping segment compressed by the pump rollers and an outlet
segment. The stopper element is an element of the tubing having an
outside diameter which is larger than the inside diameter of inlet
gap Gi (see FIG. 7) of the roller assembly housing 700. The
function of the stopper element is to become snuggly wedged within
the inlet gap Gi, thereby positioning and aligning the tubing with
respect to the rollers, and preventing the tubing from migrating or
walking through the pumphead assembly as a result of the vector
forces exerted on the tubing by the rollers. There are various
possible embodiments of the tubing and the stopper element some of
which are described in detail below.
[0016] The disclosed pumphead assembly consists of a roller
assembly housing and a roller assembly (See FIG. 6-8). The roller
assembly, not part of the present invention, can be a standard
roller assembly such as that of the Watson-Marlow pump models 313
and 314. The Watson-Marlow pumphead assemblies have a standardized
attachment plate (not part of this invention) which is permanently
affixed to the pump motor housing and allows detachable attachment
of the roller assembly housing to the pump house assembly.
[0017] The inventive roller assembly housing can be manufactured as
two attachable but non-movable parts, the posterior raceway-part
and the anterior inlet-ramp-part. The inventive tubing can be
manufactured as a single part. The inventive design reduces the
complexity and the expense of the manufacturing process and
improves safety. The tubing element and roller assembly housing
element are functional and inventive if and only if both elements
are simultaneously considered as a unique single entity.
[0018] All aspects discussed herein apply to any application of
peristaltic pumping currently known in the art or developed in the
future.
[0019] The wall thickness of the tubing can be constant or
variable. The outside diameter of the tubing can be constant of
variable, and the inside diameter of the tubing can be constant or
variable.
[0020] The novel roller assembly housing eliminates numerous parts
from prior-art roller pumps and provide a safer and simpler method
for inserting the tubing between the rollers and the pump raceway.
A method for inserting a tube set into a roller pumphead assembly
is provided wherein the tubing has a non-elastic distal Luer
connector and a proximal non-elastic IV-bag spike for connecting IV
bag and elastomeric pump tubing.
[0021] Because the spike and the Luer connector both have ODs which
can be larger than the minimum gap between the rollers and the
roller raceway within the peristaltic roller assembly housing if
they are drawn into the roller assembly they would be crushed or
they would be damage the roller assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] These and other features and advantages of the various
embodiments disclosed herein will be better understood with respect
to the following description and drawings, in which like numbers
refer to like parts throughout, and in which:
[0023] FIG. 1A is a perspective view of a peristaltic roller pump
tube having a single transitional segment with section lines
indicating a partial longitudinal cross-section view of the
tube.
[0024] FIG. 1B is a partial cross-sectional view of the tube 1A
with section lines indicating transverse cross-sectional views at
the level of the outlet segment FIG. 1C, transitional segment with
varying wall thickness FIG. 1D, pumping segment consisting of a
transitional segment with constant wall thickness and variable
outside diameter FIG. 1E and the inlet segment FIG. 1F.
[0025] FIG. 1G is perspective view of tube assembly 100 with
stopper element S and sliding stopper element SS together with the
sliding stopper ring 101 located distally on the outlet segment 190
near the male Luer lock connector 192. The section lines 1I
indicate the cross sectional view FIG. 1I showing the sliding
stopper ring 101 fitting loosely around the outlet segment 190.
[0026] FIG. 1H shows the sliding stopper ring 101 fitting snuggly
around the sliding stopper element SS with section line 1J
indicating the cross sectional view FIGS. 1J, and 1K indicates the
enlarged view FIG. 1K.
[0027] FIG. 2A is a longitudinal cross-sectional view of a
peristaltic roller pump tube having two transitional segments with
section lines indicating transverse cross-sectional views at the
level of the outlet segment FIG. 2B, pumping segment consisting of
a transitional segment with constant wall thickness and variable
outside diameter FIG. 2C and FIG. 2D, and the inlet segment FIG.
2E. The wall thickness shown in FIG. 2B is significantly thinner
than the wall thickness shown in FIG. 2E.
[0028] FIG. 3A is a longitudinal cross-sectional view of a
peristaltic roller pump tube having constant wall thickness along
its entire length and having two transitional segments with section
lines indicating transverse cross-sectional views at the level of
the outlet segment FIG. 3B, pumping segment consisting of a
transitional segment and variable outside diameter FIG. 3C and FIG.
3D, and the inlet segment FIG. 3E.
[0029] FIG. 4A is a perspective view of a peristaltic roller pump
tube having a single bump segment formed from two transitional
segments which functions as a stopper element together with section
lines indicating a longitudinal cross-section view of the tube FIG.
4B.
[0030] FIG. 4B is a longitudinal cross-sectional view of the tube
FIG. 4A showing the stopper element 446 having an internal diameter
which can be constant and having an wall thickness within the bump
segment which can be constant or of increased thickness, also
showing transverse cross-sectional views at the level of the outlet
segment FIG. 4C, and the bump segment FIG. 4D.
[0031] FIG. 5A is a perspective view of a peristaltic roller pump
tube consisting of a simple round cylindrical tube without
transitional segments showing a single bump segment which functions
as a stopper element at point 546 together with section lines
indicating a longitudinal cross-section view of the tube FIG. 5B,
and transverse cross-section lines at the level of the outlet tube
FIG. 5C, pumping segment FIG. 5D and stopper element FIG. 5E.
[0032] FIG. 6A is an anterior to posterior view of the raceway back
cover 720 showing the relative position of the roller assembly 600.
FIG. 6B is a posterior to anterior view of the front cover 710 with
the tube ramp 712 and showing the relative position of the roller
assembly 600. FIG. 6C is a plane view of prior art roller assembly
and section line indicating a longitudinal cross-sectional view
FIG. 6E. FIG. 6D is a lateral view of the prior art roller
assembly.
[0033] FIG. 7A is a perspective view of the roller assembly housing
700 together with the prior art attachment plate 730 and section
lines indicating a midline cross-sectional view FIG. 7B. FIG. 7C
shows cross sectional view of 710 and 720. FIG. 7D shows the outlet
gap Go.
[0034] FIG. 8A shows a perspective view of the raceway back cover
720.
[0035] FIG. 8B is a perspective view of the front cover 710.
[0036] FIG. 8C is a lateral view of the roller assembly housing 700
showing a ghost view of the internally located roller assembly 600
together with the prior art attachment plate 730.
[0037] FIG. 8D is an exploded view of FIG. 8C.
[0038] FIG. 9A is a perspective of a portion of the outlet segment
190 of pump tubing 100 entering the roller assembly housing 700 and
section lines indicating a midline cross-sectional view FIG. 9AX.
FIG. 9B is a perspective of a portion of the outlet segment 190 of
pump tubing 100 entering the roller assembly housing 700 and
section lines indicating a midline cross-sectional view FIG. 9BX.
FIG. 9C is a perspective of a portion of the outlet segment 140 of
pump tubing 100 entering the roller assembly housing 700 indicating
the stopper element 146 wedged within the inlet gap Gi and section
lines indicating a midline cross-sectional view FIG. 9CX.
[0039] FIG. 10 is a perspective view of the roller assembly housing
700 attached to the pump motor housing 1000.
[0040] FIGS. 11A, 11B and 11C are views of prior art disclosed by
Parrott in U.S. Pat. No. 4,767,289, Peristaltic Pump Header, issued
Aug. 30, 1988.
[0041] FIGS. 12A and 12B are views of prior art disclosed by
Montoya et al, U.S. Pat. No. 5,342,182, Self Regulating Blood Pump
with Controlled Suction, issued Aug. 30, 1994.
DETAILED DESCRIPTION
[0042] Illustrative embodiments of an improved design for
peristaltic roller pump tubing and a roller assembly housing are
described below. The following explanation provides specific
details for a thorough understanding of and enabling description
for these embodiments. One skilled in the art will understand that
the invention may be practiced without such details. In other
instances, well-known structures and functions have not been shown
or described in detail to avoid unnecessarily obscuring the
description of the embodiments.
[0043] Unless the context clearly requires otherwise, throughout
the description and the claims, the words "comprise," "comprising,"
and the like are to be construed in an inclusive sense as opposed
to an exclusive or exhaustive sense; that is to say, in the sense
of "including, but not limited to." Words using the singular or
plural number also include the plural or singular number
respectively. Additionally, the words "herein," "above," "below"
and words of similar import, when used in this application, shall
refer to this application as a whole and not to any particular
portions of this application. When the claims use the word "or" in
reference to a list of two or more items, that word covers all of
the following interpretations of the word: any of the items in the
list, all of the items in the list and any combination of the items
in the list.
[0044] FIG. 1A is a perspective view of a peristaltic roller pump
tube assembly 100 with section lines indicating a partial
longitudinal cross-section view of the tube FIG. 1B, an IV bag
spike 128 attached to the tubing inlet 129, and a male Luer lock
connector 192 attached to a tubing outlet 191. Such a single piece
of elastomeric pump tubing 110 is composed of an inlet segment 130,
a pumping segment 140, a transition segment 150, and an outlet
segment 190. The embodiment illustrated in FIG. 1A has a single
transitional segment 150.
[0045] The inlet segment 130 can have arbitrary wall thickness (WT)
and outside diameter (OD) which is strictly greater than the
maximal OD of the more distal tubing segments 140, 150, and 190.
The pumping segment 140 can have a constant WT along its entire
length which is preferably half the magnitude of gap Grr, the
minimum distance of the gap between the concave surface of a
raceway and the surface of pump rollers of a roller pump means, as
shown in FIG. 7B. The transitional segment 150 and a significant
length of the proximal portion outlet segment 190 must have a wall
thicknesses strictly less than the half the magnitude of the roller
raceway gap Grr. Furthermore the entire length of segments 140 and
150 as well as a significant length of the proximal portion of
outlet segment 190 must have an OD which is strictly less than the
OD of an inlet gap Gi or an outlet gap Go (shown in FIG. 7D) of the
roller assembly housing.
[0046] The pumping segment 140 of the pump tubing 110 is located
between the inlet and outlet segments 130, 190. The pumping segment
140 is the segment inserted into the pump raceway and cyclically
compressed by the pump rollers. The pumping segment 140 is
responsible for the pumping efficiency of a peristaltic roller pump
tube assembly 100. The larger the internal diameter (ID) of the
pumping segment 140, the greater will be the volume of fluid
ejected with each cyclic compression of the pump tube assembly
100.
[0047] The inlet segment 130 of the pump tubing 110 is the proximal
or vacuum segment of the pump tubing 110. The fluid pressure within
the inlet segment 130 is relatively low. Fluid flows into the inlet
segment 130 from a reservoir source, entering into the pump tubing
110 via the proximal end and is drawn distally by the negative
pressure generated by the peristaltic roller pump assembly 100.
[0048] The outlet segment 190 of the pump tubing 110 is the distal
or pressure segment of the tubing. The outlet segment is bounded
proximally by a pumping segment of the pump tubing 110. Fluid flows
from pumping segment 140 into the outlet segment 190 being pushed
by the positive pressure generated by the peristaltic pump
rollers.
[0049] As used herein the term stopper means or element S, the
function of which is illustrated in FIGS. 1A, 1B, 7A and 9C, is a
non-tangible circumferential annular line of points encircling the
inlet tubing segment 130, and is such that S has an diameter (Ds)
which is larger than the inside diameter (ID) of the inlet gap Gi
of the roller assembly housing. Furthermore stopper element S is
located at the first point on tubing 110 proximal to tubing
segments 140, 150, and 190 where the OD is strictly greater than
the inside diameter (ID) of the inlet gap Gi of the roller assembly
housing.
[0050] During the tube-loading process, a length of the proximal
portion of outlet segment 190, having an OD which is smaller than
the ID of Gi, is manually inserted and pulled into the roller
assembly housing through a top gap Gt, then downward though side
gaps Gs, and then, with the roller motor slowly rotating in the
forward direction, the tubing is drawn through the inlet gap Gi and
out through the outlet gap Go (not shown) of roller assembly
housing by vector forces exerted by the roller rotation. When the
larger diameter Ds of the stopper element S encounters the smaller
ID of the inlet gap Gi of the roller assembly housing, the tubing
proximal to the stopper element S becomes snuggly wedged in the
inlet gap Gi thereby securely holding the roller tubing 110 in
place and aligning the pumping segment of the roller tubing 110
with respect to the rollers.
[0051] FIG. 1B is a partial cross-sectional view of the tube
assembly 100 together with section lines indicating transverse
cross-sectional views at the level of the outlet segment 190 (FIG.
1C), transitional segment 150 with varying wall thickness (FIG.
1D), pumping segment 140 with constant wall thickness and variable
outside diameter (FIG. 1E), and the inlet segment 130 having
constant OD and constant WT 130 (FIG. 1F).
[0052] FIG. 1G shows tubing assembly 100 with an annular or
torus-shaped sliding stopper ring 101 situated on the distal outlet
segment 190 located near the Luer lock connector 192. The sliding
stopper ring 101 has an inside diameter that is equal to the
outside diameter at a point on the tube 110 designated as the
sliding stopper element point SS which is located on the pumping
segment and is distal to stopper element S. The OD at SS is
strictly less than the OD at S. The position of the sliding stopper
ring 101 can be moved in the direction of the large arrow toward
the point SS. The section lines 1I indicate the cross sectional
view of the outlet segment 190 where the sliding stopper ring 101
fits loosely about segment 190.
[0053] FIG. 1H shows the tubing 110 of the tubing assembly 100 with
the sliding stopper ring 101 situated proximally on the pumping
segment 140 and fitting snuggly at the point SS. The OD at SS is
strictly less than the OD at stopper element S. The section lines
1J indicate the cross sectional view of the pumping segment 140 and
snuggly fitting sliding stopper element 101.
[0054] Also shown in FIG. 1H is the sliding stopper element 101S
located on the stopper ring 101. The sliding stopper element 101S
is a non-tangible circumferential annular line of points encircling
a distal portion of sliding stopper ring 101, and is such that 101S
has an inside diameter (Ds) equal to the diameter Ds of stopper
element S. The section line 1J indicates the cross sectional view
of FIG. 1H at the level of the point SS and sliding stopper ring
101.
[0055] FIG. 1J at the level of the point SS and sliding stopper
ring 101 where the inner member is a cross sectional view of the
pumping segment 140 and the outer member a cross sectional view of
sliding stopper ring 101.
[0056] FIG. 1K is an enlarged detailed view of FIG. 1H showing
relative positions of S and SS, as well as the sliding stopper
element 101S on the sliding stopper ring 101.
[0057] As used herein the outside diameter (OD) of a tube is the
diameter of the circle congruent with the outer surface of a
circular tube. As used herein the inside diameter (ID) of a tube is
the diameter of the lumen of a tube having a
circular-cross-section. The ID of the pumping segment 140 of the
pump tubing 110 is an important factor in determining the volume of
fluid that is pumped in one 360 degree cycle of the peristaltic
pump. For any given rate of roller rotation the fluid flow rate is
maximized by using a tube having the largest tube ID. To achieve
higher pump precision, one should use tubing having a relatively
small ID with the pump rollers rotating at a relatively high
rate.
[0058] As used herein the wall thickness (WT) is the thickness of
the wall of a section of pump tubing 110. The wall thickness for
the pumping segment 140 of tubing is typically at least half the
minimal distance between the rollers and the roller raceway.
[0059] FIG. 2A shows a partial cross-section of another embodiment
200 of a roller pump tubing which prevents wrong-way or flip-flop
tubing insertion into the roller pumphead assembly. Shown are
section lines indicating cross-section views of the tubing at the
level of the outlet segment 290, FIG. 2B, at the level of the
pumping segment 240, FIG. 2C, at the point 244 on the tubing 101
where the largest OD is located, and at the level of the inlet
segment 230, FIG. 2E. The wall thickness is constant along the
pumping segment 240. The proximal inlet opening is 219 and the
distal outlet opening is 291.
[0060] In order to be able to insert a segment of the tubing into
the roller assembly housing, the wall thickness of the segment is
no greater than half the width of the top gap Gt, FIG. 9A. For
example, if the wall thickness of the outlet segment 290 is less
than half the width of the top gap Gt, then segment 290 fits inside
top gap Gt and therefore may be inserted through Gt and into the
space between the roller raceway and the rollers, referred to as
the roller raceway gap Grr in FIG. 7B. On the other hand, if the
wall thickness of a segment of the tube, for example the inlet
segment 230, exceeds half the width of top gap Gt then it is not
possible to insert the inlet segment 230 into the roller assembly
housing.
[0061] In certain situations, such as extracorporeal blood
circulation, serious injury may occur to the patient if the roller
pump tubing is inserted into the roller assembly housing in the
wrong direction, thereby possibly pumping blood from the patient
rather than to the patient (see Parrott et al, U.S. Pat. No.
4,767,289, issued on Aug. 30, 1988). To prevent this type of error,
the tubing is manufactured such that the wall thickness of the
inlet segment exceeds half the width of the top gap Gt while the
wall thickness of the proximal portion of the outlet segment is
strictly less than half the width of the top gap Gt. Thus if the
wall thickness of the inlet segment 130 is strictly greater than
half of width of top gap Gt, then the WT of 130 is too large and
prevents 130 being inserted through Gt. In other words, tube
assembly is prevented from being inserted in the wrong or flip-flop
direction into the roller assembly housing 700 (FIG. 9A).
[0062] FIG. 3A demonstrates another embodiment of the roller pump
tubing 300, with the approximate location of the stopper element S.
In this design the wall thickness is constant throughout the length
of the tubing, together with section lines which designate the
cross-sectional views of the outlet segment 330, FIG. 3B, the
pumping segment 340, FIG. 3C, and the outlet segment 390, FIG. 3E.
Section lines 3D indicates the approximate point 344 of the maximum
OD on the tubing 300, FIG. 3D.
[0063] FIG. 4A is a perspective view of another embodiment of
simplified peristaltic tubing wherein the inlet segment 430 and the
outlet segment 490 have the same radial dimensions. Section lines
4B indicate a longitudinal cross-section view (FIG. 4B). The
stopper element S is located on segment 460 which is formed during
the tubing extrusion process as a localized enlargement of the tube
OD. FIG. 4B shows a longitudinal cross-section view of tube 400
where the inner diameter thereof is substantially constant and
equal along the entire length of the inlet segment 430, the pumping
segment 440, and the outlet segment 490. The centrally located
segment with an enlarged OD 460 is formed by the extrusion process
to provide a stopper element S. Section lines 4C indicate the
cross-section view (FIG. 4C) of the outlet segment 490. Section
lines 4D indicates the cross-section view (FIG. 4D) of segment 460.
Segment 460 which has an enlarged OD has an enlarged wall thickness
and ID equal to the ID of all other segments of the tube. In an
alternate embodiment the segment 460 with an enlarged OD has an ID
that is larger than the ID of all other segments of the tube.
[0064] FIG. 5A is a perspective view of tube assembly 500 which is
another embodiment of the present invention. The tube assembly 500
is constructed of a suitable elastomeric material such as durometer
60 PVC and consists of a single uniform tube 501 together with an
additional external circumferential semi-tubular segment 561
providing a localized enlarged OD which functions as a stopper
element S. Tubing 501 is subdivided into an inlet segment 530, a
pumping segment 540, and outlet segment 590.
[0065] Section lines 5B indicate a longitudinal cross sectional
view FIG. 5B of tube 500. Section lines 5C indicate a cross
sectional view (FIG. 5C) of the outlet segment 590. Section lines
5D indicate cross sectional view (FIG. 5D) at the level of the
pumping segment 540 of tube 501. Section lines 5E indicate cross
sectional view of FIG. 5E of the tube assembly 500 at the level of
segment 560. The external circumferential semi-tubular segment 561
has an ID equal to the OD of 501 wherein the tubular segment 561 is
slit longitudinally, then opened, then wrapped around tube 501 and
finally cemented in place.
[0066] FIG. 6A is an anterior-posterior (front to back) view the
raceway back cover 720 of the pump roller means, or roller assembly
housing 700 (FIG. 7A), showing the raceway 714 in relation to the
roller assembly 600. FIG. 6B is a posterior-anterior (back to
front) view of the front cover of the roller assembly housing 700
(FIG. 7A) showing the tube-ramp 712 in relation to the roller
assembly 600. FIGS. 6C, 6D and 6E represent prior art peristaltic
roller assembly 600 which is incorporated into the present
invention. FIG. 6D is a side view of the roller assembly. FIG. 6C
shows a frontal view of 600 with section lines 6E indicating the
cross sectional view FIG. 6E. These figures show the rollers 610,
roller axels 660, central axel 650, roller bracket 620 and a
ball-bearing raceway assembly 640.
[0067] The roller assembly 600 may generally refer to and may
include the combined assembly of cylindrical rollers, axels which
pass through the rollers, brackets which secure the roller axels,
main-axe ball bearings and the main axel with about which the
brackets rotate and which is rotatably connected to the pump motor.
For example see FIG. 6A, 6B, 6C.
[0068] The roller assembly housing 700 may generally refer to and
may include the roller raceway and the associated structural
components which securely hold and house the roller assembly
together with the flanges and attachment members which securely
hold the tubing in place and alignment with respect to the rollers.
The roller assembly housing may also include a door assembly which
opens to allow insertion of the tubing between the roller raceway
and the roller assembly, and closes to prevent damage to the roller
assembly and to provide protection against injury to the operator's
fingers.
[0069] FIG. 7A, the inlet side, and FIG. 7D, the outlet side, are
perspective views of the roller assembly housing 700 with section
lines 7B indicating the cross sectional view FIG. 7B which shows
the spatial relationship between roller assembly 600 and roller
assembly housing 700. The roller assembly housing consists of only
two parts: the tube-ramp front cover 710 and the raceway back cover
720. The attachment plate 730 detachably attaches 700 to the motor
assembly housing 1000 (FIG. 10), and is prior art and not a part of
the present invention. FIG. 7C is an enlarged view of FIG. 7B
wherein the roller assembly 600 and the attachment plate 730 have
been removed for clarity. The topological or geometrical
relationship between the front cover 710 and the raceway back cover
720 creates a set of interconnected openings or gaps including the
top gap Gt, the side gap Gs, the inlet gap Gi, outlet gap Go,
roller raceway gap Grr and tube ramp 712 which allow the unique
process of inserting, aligning and securing the pump tube inside
700, while requiring no moving parts. It is remarkable that the
present inventive roller pump housing 700, while consisting of only
two parts 710 and 720, has no moving parts. Nevertheless, any of
the embodiments of the inventive pump tubing with stopper element,
shown in FIGS. 1A, 2A, 3A, 4A, 5A together with the roller assembly
housing 700 allow efficient and safe peristaltic pump function
while minimizing manufacturing costs. A more detailed description
of the process of inserting pump tubing into the roller assembly
housing 700 will be described in detail in the discussion of FIG.
9A below.
[0070] FIG. 8A is a perspective view of the raceway back cover 720
of the roller assembly housing 700 (FIG. 7A) showing the raceway
714. FIG. 8B is a perspective view of the front cover 710 of the
roller assembly housing 700 (FIG. 7A) showing the tube ramp 712.
The front cover 710 and the back cover 720 are attached by any
appropriate means, for example by means of nuts and bolts (not
shown) or by cementing the two pieces together. FIG. 8C shows a
side view of the roller assembly housing 700 together with the
interior location of the roller assembly 600. FIG. 8D is an
exploded view of FIG. 8C, and is intended to further illustrate the
spatial relationship between the roller assembly 600 and the two
constituent parts, the front cover 710 and the raceway back cover
720 of the roller assembly housing 700. FIGS. 8C, 8D provide views
of the top gap Gt, the side gap Gs, the inlet gap Gi, and tube ramp
712.
[0071] FIGS. 9A, 9B, and 9C are perspective views of the roller
assembly housing 700 and pump tubing 100 at three sequential stages
in the process of inserting the tube 100 into roller assembly
housing 700. FIGS. 9AX, 9BX, and 9CX are the respective cross
sectional views of FIGS. 9A, 9B, and 9C, as indicated by section
lines AX, BX and CX in FIGS. 9A, 9B, and 9C.
[0072] FIGS. 9A and 9AX show pump tube 100 positioned parallel to
the top of the roller assembly housing 700 with outlet segment 190
of the pump tube 100 positioned longitudinally within the opening
of the top gap Gt. If the wall thickness of 190 is less than half
the width of top gap Gt then outlet segment 190 may be gently
pulled into Gt in the direction of the heavy arrows shown in FIG.
9A. The first stage of the process of inserting and properly
positioning the tube 100 in the roller assembly housing 700
consists actuating the slow rotation of the roller assembly so that
a gentle vector force is applied to the tubing in the direction of
the dashed arrows while the operator simultaneously pulls the
outlet segment 190 down into the top gap Gt and down along the tube
ramp 712 which is part of the front cover 710 toward the functional
position of the tube 100 within roller raceway gap Grr. The roller
raceway gap Grr is the space between the raceway 714 and roller 610
of the roller assembly 600. The roller assembly housing 700 is the
assembly of two parts, the raceway back cover 720 and the front
cover 710.
[0073] FIGS. 9B and 9BX show the outlet segment 190 of pump tube
100 having been pulled down into the side gap Gs and pulled toward
the inlet gap Gi in the general direction of the heavy arrows while
simultaneously the rotating rollers pull the tubing through the
roller assembly housing 700 in the direction of the dashed
arrows.
[0074] As the tubing is pulled through the roller assembly housing
700 the outlet segment 190 exits 700 while the pumping segment 140
and the inlet segment 130 are pulled toward the inlet gap Gi of the
roller assembly housing 700. Simultaneously, as tube 100 is pulled
downward along the tube ramp 712 of the front cover 710, it is also
pulled backward toward the raceway 714, which is part of the back
cover 720, and the roller raceway gap Grr.
[0075] FIGS. 9C and 9CX show tube 100 as having been pulled into
its functional position within the roller raceway gap Grr between
the roller 610 of the roller assembly 600 and the raceway 714 of
the back cover 720. When the stopper element S on pump tube 100
reaches the inlet gap Gi, the stopper element becomes snuggly
wedged into the aperture of the inlet gap Gi. With the stopper
element S snuggly positioned within the inlet gap Gi, the pumping
segment 140 of the tube assembly 100 is properly positioned within
the roller raceway gap Grr and securely fixed within the roller
assembly housing 700. With the proximal end of the inlet segment
connected to a reservoir source of fluid (not shown), the continued
rotation of the roller assembly produces efficient peristaltic
pumping action of the fluid through the tubing assembly 100 and out
its distal outlet end.
[0076] FIG. 10 shows the motor assembly housing 1000 with the
roller assembly housing 700 attached to the pump motor housing 1001
by means of the attachment plate 730.
[0077] FIGS. 11A, 11B, and 11C show the prior art drawing of
Parrott et al (U.S. Pat. No. 4,767,289) which disclose a
peristaltic pump 20 to be used for extracorporeal circulation of
blood and a complex peristaltic tubing 10 that utilizes two sets of
four concentric tubes to construct a pressure-control valve 34 and
a one-way-flow-valve 36 in order to prevent pumping blood in the
wrong direction in case the tubing is inadvertently inserted within
the pump in the wrong direction. In contrast, the second embodiment
of the present invention (see FIG. 2A) is designed such that it is
impossible to insert the tubing in the wrong direction.
[0078] The Parrott prior art patent reference discloses peristaltic
pump tubing which is not a single piece of continuous tubing but
must be a combination of an inlet tubing 26, which is connected to
by means of an inlet barbed hose attachment 56 to the pump tubing
10, and an outlet barbed hose attachment 66 which connects pump
tubing 10 to the outlet tubing 90. Peristaltic tube attachment
members such as 56 and 66 add complexity and expense to the
manufacturing process and have a tendency to leak under high
pressure. In contrast, all the embodiments of the peristaltic
tubing disclosed in the present invention are constructed by means
of a continuous extrusion which eliminates tube connectors,
simplifies tubing assembly and sterilization processes and
eliminates the risk of fluid leaks between attachment members.
[0079] The Parrott prior art patent reference appears to disclose a
method for securing the pump tube 10 within the peristaltic pump
housing 20 which relies on a pair of tube clamps TC (not described
by Parrott) and also relies on the difference in outer diameter
between the larger diameter rigid tubing of the pressure valve
housing 56 and the one-way-flow valve housing 62 relative to the
smaller diameter flexible central portion of the pump tube 10. The
step-off 60 between the larger diameter pressure valve housing tube
56 and smaller diameter central tube segment 30 helps to secure the
pump tube 10 in place with respect to the pump housing 20 after a
tube clamp TC has entrapped the smaller diameter central tube
segment 30. Similarly the step-off 64 between the larger diameter
pressure valve housing tube 62 and smaller diameter central tube
segment 30 helps to secure the pump tube 10 in place with respect
to the pump housing 20 after a tube clamp TC has entrapped the
smaller diameter central tube segment 30. Parrott does not discuss
the process and means by which pump tube 10 is placed within the
tube clamps TC. Based on simple geometry and elementary topological
considerations there must be a means of opening the clamps TC,
inserting the tube 10 between two semicircular jaws SJ (not
described by Parrott) of the clamp TC and then closing the clamp TC
about the tube 10. The mechanism for opening and closing a clamp TC
and preventing the clamp from inadvertently opening and
unintentionally releasing of the pump tubing 10 is also not
described by Parrott. In contrast one of the principal claims of
the present invention is the novel method of inserting pump tubing
into the roller assembly housing and securely fixing the pump
tubing within the roller assembly housing (described in detail
below) such that the roller pump housing has no moving parts.
[0080] FIGS. 12A and 12B show the prior art drawings of Montoya
(U.S. Pat. No. 5,342,182), which disclose tubing 38 "provided with
a variable cross-sectional width," which is designed to "minimize
the total pump priming volume". Montoya's tubing has constant wall
thickness and the variability of the tubing width. Such a tubing
design does require ancillary connectors and attachment means 40,
typically a clamp or other well known mechanism, to attach the pump
tube 38 to the supply tube 53 and the outlet tube 55 and also
requires an anchoring mechanisms 60 consisting of multiple parts to
attach the tubing to the roller assembly housing and to orient tube
38 and to prevent tube migration.
[0081] The tubing with variable cross-sectional inside diameter and
variable outside diameter as described by Montoya consisting of a
filling region 118, constant width intermediate section 119 at the
end of the filling region 118, smooth width transition segment 120
with decreasing width, a decreased or narrower constant width
section 121, and finally an outlet region 122 of tube 38. The
dilated or largest outside segment of the Montoya tubing 38 is
intended to be compressed by the rollers 36 located inside the
roller assembly housing (not shown). Montoya (U.S. Pat. No.
5,342,182 in column 7, lines 21-28) states, "Also, it is
advantageous to maintain a relatively narrow cross-section at the
beginning of the inlet region 118, where the incoming roller 36
just begins to trap the fluid in the filling region, thus allowing
for a lower tension to occlude and hold the filling pressures.
Otherwise, more fluid may slip past the rollers and not be pumped
forward. For this reason, the filling region 118 is not made as
wide as the widest part of the tubing 38." In contrast, in the
present invention the segment of tubing with the largest outside
diameter must always be located outside the roller assembly housing
where it can never be compressed by the rollers and where its
primary function is to act as a stopper which helps to align the
tubing with the rollers and prevents the tubing from migrating
through the pump. Thus, although the Montoya tube and the present
invention have somewhat similar geometric shapes their respective
functions are entirely different and unrelated.
[0082] The following describes a suitable pump arrangement for
implementation of the above-described peristaltic pump system. The
system may include a pumphead assembly that is a HK Surgical
pumphead (interchangeable with a Watson-Marlow 313D in the sense
that it uses the identical attachment plate and identical roller
assembly). The roller tubing 110 may have a 1.6 mm or 2.4 mm wall
thickness with 3 or 4 roller peristaltic-pump-head, such as
Watcho-Marlow 313D or 314D pumpheads. The general overall
dimensions may have a height of 3 to 5 inches, a width of 9 inches
and a depth of 13 inches. The peristaltic pump system may have a
variety of mounting options, such as table-top mount with non-skid
foot-pads, or IV pole mountable. The peristaltic pump system may be
configured to be operated in any position (upright, on its side,
upside down). It is contemplated that the housing being relatively
easy to open and closed to access pump components for repairs and
inspection. The pump may be powered by varies means such as AC
current and/or efficient rechargeable batteries. The pump motor may
be a stop motor and may be two directional. A control interface may
control the pump directionality. In this regard, the control
interface may include analog (such as turn-knob dials) and/or
digital (such as an LCD touch screen.). Suitable pump flow rates
may be from 0 ml/min up to 800 ml 1000 ml per minute. Audible
indicator tones may be used to indicate pump-rate and pulse
duration. In a continuous mode a rate of beeping tone may correlate
with a rate of rotation of the peristaltic rollers. In a pulse mode
a continuous audible tone is used when the pump motor is actuated
and pumping. The continuous audible tone has a variable tone
wherein the pitch of frequency (Hz) of the tone varies in direct
proportion to the rotation rate of the pump rollers. Volume
controls may be provided for all audible indicators. Various safety
features may be provided. A safety cut-off switch may be provided
that is actuated when the housing is open. A warning may be
provided for low batteries levels. A warning may be provided when
fluid flow has stopped, for example when an IV bag is empty.
[0083] The pump may have a variety of pump controls. An
"insert-tubing" button may control the roller to rotate
continuously at a slow rate during insertion of the tubing into the
pumphead assembly. A "remove-tubing" button may control the roller
in an opposite direction. A "pump-prime" button may be held down to
prime the pump tubing (fill the tubing with fluid and purge the
tubing of air bubbles) following insertion of the tubing. Two
pneumatic connection ports may be provided for air-bellow actuator
switches to accommodate remote foot pedal switches preferably
located on a surface that is easily accessed (near front control
panel). An additional pneumatic connection port may be provided for
an extra-sensitive pneumatic air-bellows switch actuator. The pump
actuator may have several modes of operation. There may be a
"persistent pressure" mode where the pump operates for as long as
the bellow is compressed. There may be a "radio button" mode where
the pump starts with an initial compression and stops with second
compression. There may be a "trigger" mode where an initial
compression starts the pump for a predetermined limited duration
(the duration may be user selected). There may be a "gas peddle"
mode where the rate of roller rotation depends on the degree of
pressure applied to a bellows-switch. The pump motor may have a
various flow modes. There may be a "continuous flow" mode where
fluid flow is continuous. There may be a "pulsatile flow" mode
where fluid flow is pulsatile. This may include on/off switch, a
control to set pumping duration of continuous pumping action, and a
control to specify the pause duration between sequential
pulses.
[0084] The teachings provided herein can be applied to other
systems, not necessarily the system described herein. The elements
and acts of the various embodiments described above can be combined
to provide further embodiments. All of the above patents and
applications and other references, including any that may be listed
in accompanying filing papers, are incorporated herein by
reference. Aspects of the invention can be modified, if necessary,
to employ the systems, functions, and concepts of the various
references described above to provide yet further embodiments of
the invention.
[0085] These and other changes can be made to the invention in
light of the above Detailed Description. While the above
description details certain embodiments of the invention and
describes the best mode contemplated, no matter how detailed the
above appears in text, the invention can be practiced in many ways.
Details of the system may vary considerably in its implementation
details, while still being encompassed by the invention disclosed
herein.
[0086] Particular terminology used when describing certain features
or aspects of the invention should not be taken to imply that the
terminology is being redefined herein to be restricted to any
specific characteristics, features, or aspects of the invention
with which that terminology is associated. In general, the terms
used in the following claims should not be construed to limit the
invention to the specific embodiments disclosed in the
specification, unless the above Detailed Description section
explicitly defines such terms. Accordingly, the actual scope of the
invention encompasses not only the disclosed embodiments, but also
all equivalent ways of practicing or implementing the
invention.
[0087] The above detailed description of the embodiments of the
invention is not intended to be exhaustive or to limit the
invention to the precise form disclosed above or to the particular
field of usage mentioned in this disclosure. While specific
embodiments of, and examples for, the invention are described above
for illustrative purposes, various equivalent modifications are
possible within the scope of the invention, as those skilled in the
relevant art will recognize. Also, the teachings of the invention
provided herein can be applied to other systems, not necessarily
the system described above. The elements and acts of the various
embodiments described above can be combined to provide further
embodiments.
[0088] All of the above patents and applications and other
references, including any that may be listed in accompanying filing
papers, are incorporated herein by reference. Aspects of the
invention can be modified, if necessary, to employ the systems,
functions, and concepts of the various references described above
to provide yet further embodiments of the invention.
[0089] Changes can be made to the invention in light of the above
"Detailed Description." While the above description details certain
embodiments of the invention and describes the best mode
contemplated, no matter how detailed the above appears in text, the
invention can be practiced in many ways. Therefore, implementation
details may vary considerably while still being encompassed by the
invention disclosed herein. As noted above, particular terminology
used when describing certain features or aspects of the invention
should not be taken to imply that the terminology is being
redefined herein to be restricted to any specific characteristics,
features, or aspects of the invention with which that terminology
is associated.
[0090] In general, the terms used in the following claims should
not be construed to limit the invention to the specific embodiments
disclosed in the specification, unless the above Detailed
Description section explicitly defines such terms. Accordingly, the
actual scope of the invention encompasses not only the disclosed
embodiments, but also all equivalent ways of practicing or
implementing the invention under the claims.
[0091] While certain aspects of the invention are presented below
in certain claim forms, the inventor contemplates the various
aspects of the invention in any number of claim forms. Accordingly,
the inventor reserves the right to add additional claims after
filing the application to pursue such additional claim forms for
other aspects of the invention.
[0092] The above description is given by way of example, and not
limitation. Given the above disclosure, one skilled in the art
could devise variations that are within the scope and spirit of the
invention disclosed herein. Further, the various features of the
embodiments disclosed herein can be used alone, or in varying
combinations with each other and are not intended to be limited to
the specific combination described herein. Thus, the scope of the
claims is not to be limited by the illustrated embodiments.
* * * * *