WO2001011236A1

WO2001011236A1 - Fluid pump for medicaments

Info

Publication number: WO2001011236A1
Application number: PCT/IB2000/001233
Authority: WO
Inventors: Igor Denenburg
Original assignee: Igor Denenburg
Priority date: 1999-08-09
Filing date: 2000-08-09
Publication date: 2001-02-15
Also published as: AU6590100A; US6224346B1

Abstract

An apparatus for moving fluid from a first location to a second location that comprises a housing (12) containing a pump body (16) having a central passageway (18) with a fluid inlet (20) and first (21) and second (22) fluid outlets in communication with the passageway. A shuttle (24) having first (26) and second (28) fluid chambers is movable within the passageway (18) of the body (16) between first and second positions. First (36), second (38), third (32) and fourth (30) generally annular shaped fluid passageways provided in the shuttle (24) permit selective fluid communication between the first (26) and second (28) fluid chambers of the shuttle (24) and the inlet (20) and outlet (21, 22) ports of the pump body (16). First (36) and second (38) inlet passageways provided in the shuttle (24) permits selective fluid communication between the inlet (20) of the pump body (16) and the first (26) and second (28) fluid chambers of the shuttle (24).

Description

FLUID PUMP FOR MEDICAMENTS

S P E C I F I C A T I O N

Background of the Invention

Field of the Invention

The present invention relates generally to fluid pumps. More particularly,

the invention concerns a fluid pump for precisely controlling the transfer of me¬

dicaments and other beneficial agents from a source of fluid to a patient.

Discussion of the Prior Art

A number of approaches have been suggested in the past for delivering fluid

medicaments and other beneficial agents to a patient. The most common apparatus

for this purpose is the so-called "gravity feed system". This system involves the

use of a flexible bag that is supported above the patient and contains the fluid to be

delivered. The fluid is delivered to the patient by force of gravity via a flexible

tube that extends between the bag and the patient. The rate of fluid flow to the pa¬

tient from the bag is basically a function of the amount of restriction of the tube

leading to the patient.

To more precisely and reliably control the rate of fluid flow to the patient,

several types of devices have been proposed. These devices are generally either mechanical or electronic. Exemplary of one prior art mechanical type delivery de¬

vice is that described in U. S. Patent No. 3,464,359 issued to King et al. The King

et al device comprises a fluid pump for moving fluid from one system to another

under pressure and includes means to assert positive control over the flow rate and

also to isolate the outlet of the pump from small quantities of air occurring therein.

The device basically comprises a pump body having a central chamber provided

with an inlet and an outlet port. Pistons are associated with each port and are mov¬

able within the central chamber between a port open and port closed positions.

The pistons are constructed and arranged so as to move fluid from one system,

through the inlet port of the pump, to the central pump chamber of the pump, to¬

ward the outlet port of the pump and then into the second system.

Another prior art mechanical pumping device is disclosed in U.S. Patent No.

5,163,822 issued to Koelln. The Koelln device comprises a radial piston pump

having a pump body with two pump chambers disposed in a straight line. Pistons

reciprocate within the pump chambers and are coupled to an actuator that is ro-

tatable about an axis which bisects the straight line and ftmctions to reciprocate the

pistons in opposite directions. Each pump chamber is connected to an intake fluid

duct and a discharge fluid duct. The inlet ducts are connected to a common main

intake duct and the discharge fluid ducts are connected to a common main dis¬

charge duct. The actuator controls the operating components of the apparatus and cooperates with the valves thereof, which function to open and close the valve

ducts.

In addition to mechanical type pumping devices, a number of different types

of micro processor controlled, electronic pumps have been proposed for the con¬

trolled delivery of various medicaments to a patient. Exemplary of one prior art

pump of this type is that described in U. S. Patent No. 5,069,668 issued to

Boydman. The pump there described is of a character that is capable of receiving a

wide variety of commands as by pushing buttons or other controls in conjunction

with viewing a changing display of information that is presented on a screen and of

carrying out the entered commands as by causing the pumping mechanism to dis¬

pense a series of carefully timed, precisely determined quantities of liquid medi¬

cine from a reservoir. As a general rule, electronic pumps tend to be complex and

are usually quite expensive.

The thrust of the present invention is to provide an elegantly simple fluid

pump suitable for the reliable transfer to a patient of liquids such as intravenous

solutions and liquid medicaments at precisely controlled flow rates.

Summary of the Invention

It is an object of the present invention to provide a simple, compact and

highly efficient fluid pump for delivering a wide variety of fluids from a fluid 01/11236

source to a remote location as, for example, to a patient at precisely controlled flow

rates.

Another object of the invention is to provide an apparatus of the aforemen¬

tioned character, which is highly reliable in operation and one, which maintains an

accurate and stable fluid flow from the source of the fluids to the patient.

Another object of the invention is to provide a pumping apparatus of the

character described in the preceding paragraphs in which no valves are required to

control fluid flow toward and away from the pumping apparatus.

Another object of the invention is to provide a fluid pump of the class de¬

scribed in which the volume of fluid transferred from the source of fluid to the pa¬

tient can be varied and closely controlled to enable fluid delivery to the patient at

very low flow rates.

Another object of the invention is to provide a fluid pump of the character

described in the preceding paragraphs which is made up of relatively few compo¬

nent parts, is economical to manufacture, is easy to use and requires minimum

maintenance.

By way of summary, one form of the apparatus of the invention for moving

fluid from a first location to a second location comprises a housing containing a

pump body having a central passageway with a fluid inlet and first and second

fluid outlets in communication with the passageway. A shuttle having first and O 01/11236

second fluid chambers is movable within the passageway of the body between first

and second positions. First, second, third, and fourth generally annular shaped

fluid passageways provided in the shuttle permit selective fluid communication

between the first and second fluid chambers of the shuttle and the inlet and outlet

ports of the pump body. First and second inlet passageways provided in the shuttle

permits selective fluid communication between the inlet of the pump body and the

first and second fluid chambers of the shuttle. A piston is reciprocally movable

within the shuttle chambers by a uniquely configured operating means, such as a

cam ring. The reciprocation piston functions, not only to control fluid flow

through the shuttle, but also ftmctions to move the shuttle between its first and sec¬

ond positions within the central passageway of the pump body. With the novel

construction thus described, fluid is expelled from the first chamber of the shuttle

as the piston moves from a first position toward a second position and, at the same

time, fluid is aspirated from the fluid source into the second chamber of the shuttle.

During pumping operations, fluid is expelled from the second chamber of the shut¬

tle as the piston moves from the second position toward the first position and fluid

is simultaneously aspirated from the fluid source into the first chamber of the shut¬

tle. With this unique arrangement, each movement of the piston permits a precise,

known volume of fluid to be expelled from one chamber of the shuttle and at the same time accomplishes the controlled aspiration into the other chamber of a fixed

volume of fluid from the fluid source.

Brief Description of the Drawings

Figure 1 is a generally perspective view of one form of the basic pump appa¬

ratus of the invention for controllably pumping fluid from a source of fluid toward

a patient via an administration line.

Figure 1 A is an enlarged, generally perspective view of the operating com¬

ponents of the pumping unit shown in figure 1.

Figure 2 is a cross-sectional view of the operating components shown in fig¬

ure 1A illustrating the position of the components in a starting configuration.

Figure 2 A is an enlarged, fragmentary, cross-sectional view of the control

portion of the pumping device.

Figure 2B is a generally perspective view of the shuttle component of the

pumping device showing the annular shaped fluid passageways formed therein.

Figure 3 is a cross-sectional view similar to figure 2, but illustrating the po¬

sition of the components of the apparatus after the piston has been moved from a

first position toward a second position.

Figure 3 A is an enlarged, fragmentary, cross-sectional view of the central

portion of the device as it appears in figure 3. Figure 4 is a cross-sectional view similar to figure 3, but showing a further

movement of the piston toward the second position to cause the shuttle to move

from the first position shown in figures 2 and 3 to the position shown in figure 4.

Figure 4 A is an enlarged, fragmentary, cross-sectional view of the central

portion of the device as it appears in figure 4.

Figure 5 is a cross-sectional view similar to figure 4, but showing movement

of the piston in an opposite direction toward the first starting position.

Figure 5 A is an enlarged, fragmentary, cross-sectional view of the central

portion of the device as it appears in figure 5.

Figure 6 is a cross-sectional view similar to figure 5, but showing further

movement of the piston to the right to cause the shuttle to return to its first starting

position.

Figure 6A is an enlarged fragmentary, cross-sectional view of the central

portion of the device as it appears in figure 6.

Figure 6B is an enlarged, fragmentary, cross-sectional view of the pumping

components of the apparatus in a pump priming position.

Figure 7 is a side-elevational, cross-sectional view of an alternate form of

pumping apparatus of the present invention. Description of the Invention

Referring to the drawings and particularly to figures 1, 1A, and 2, one form

of the apparatus of the invention for moving fluids from a first location, such as a

fluid source "S" toward a second location, such as an infusion line "L" can be seen

to comprises a housing 12 within which is mounted a cam ring 14 and a pump

body 16. Pump body 16 has a central passageway 18 provided with an inlet port

20 and spaced apart first and second fluid outlet ports 21 and 22 respectively that

are in fluid communication with passageway 18 via a uniquely configured shuttle

component 24.

In a manner presently to be described, shuttle component 24 is movable

within central passageway 18 from the first position to a second position. As best

seen in figures 2, 2A, and 3 shuttle 24 includes first and second fluid chambers 26

and 28 respectively. Shuttle 24 also includes first, second, third and fourth gener¬

ally annular shaped fluid passageways 30, 31, 32, and 33 respectively that permit

selective fluid communication between first and second chambers 26 and 28 of

shuttle 24 and first and second fluid outlet ports 21 and 22 of body 16 (figure 2B).

Shuttle 24 also includes first and second inlet passageways 36 and 38 which permit

fluid communication between first and second fluid chambers 26 and 28 of shuttle

24 and fluid inlet port 20 of body 16. It is to be understood that passageways 36

and 38 are part of their relevant channels and are shown in the upper position only for demonstration and could be at other locations around the circle. Additional

passageways could, of course, be provided if desired.

To control fluid flow through the pump and to move shuttle 24 between its

first and second positions, a piston 40 is reciprocally movable between first and

second positions by a piston operating means, the character of which will presently

be described. As best seen in figures 2 and 3, piston 40 has a first portion, gener¬

ally designated by the numeral 40a, that is sealably movable within first chamber

26 of shuttle component 24 and a second portion, generally designated by the nu¬

meral 40b, that is sealably movable within second fluid chamber 28 of shuttle 24.

In the form of the invention shown in figures 1 through 6, the means for

moving piston 40 between its first and second position comprises the previously

identified cam ring 14 which is of the general configuration best seen in figure 2.

Cam ring 14 is controllably rotated in either a clockwise or counterclockwise di¬

rection by a driving means shown here as a drive wheel 14a (figure 2) which can

be rotated by an electric motor or other mechanical means well known to those

skilled in the art. Cam ring 14 here comprises three circumferentially spaced-apart

cam lobes or protuberances 46, 48, and 50. Disposed between protuberances 46

and 48 is a segment 52 of varying wall thickness. Similarly, a segment 54 of

varying wall thickness is disposed between protuberances 48 and 50 and a segment

56 of varying wall thickness is disposed between protuberances 50 and 46. As in- O 01/11236

dicated in figures 2 through 6, the ends 40c and 40d of piston 40 are always main¬

tained in contact with the cam ring as the cam ring is rotated tlirough an arc of 360

degrees. More particularly, when the apparatus is in the position shown in figure

2, end 40c of piston 40 is in engagement with varying wall thickness segment 56

while end 40d of the piston is in engagement with protuberance 48.

It is to be noted that when the piston is in the position shown in figures 2 and

2A, shuttle 24 is in its first position. Rotation of cam ring 14 into the position

shown in figure 3 and 3A will cause increasing wall thickness segment 56 to move

the piston toward the left in the direction of arrow 55 causing fluid to be expelled

from first chamber 26 via fluid passageways 32 and 36 of the shuttle and first out¬

let port 21 of the pump body. At the same time, due to the suction of portion 40b

of piston 40 as it moves within chamber 28, fluid will be aspirated into second

chamber 28 via inlet port 20 of pump body 16 and fluid passageways 31 and 38 of

shuttle 24 (figure 3). Continued movement of the piston to the left by protuberance

50 into the position shown in figures 4 and 4A will cause shuttle 24 to be shifted to

the left to the second position shown in figures 4 and 4A. In this second position

shuttle inlet 36 is in communication with pump body inlet port 20 and shuttle fluid

passageway 31 is in communication with pump outlet port 22.

As cam ring 14 continues to rotate, piston 40 will be urged to the right by the

increasing wall thickness of segment 52 into the position shown in figures 5 and 5A causing fluid to be urged outwardly of chamber 28 through shuttle fluid pas¬

sageway 31 and into second pump outlet port 21. At the same time, due to the

suction caused by the movement of portion 40a of piston 40 within chamber 26,

fluid will be aspirated into chamber 26 via pump inlet 20. Continued movement of

piston 40 to the right by protuberance 46 in the direction of the arrows 59 in fig¬

ures 5 and 6, will cause shuttle component 24 to move into the original starting po¬

sition shown in figures 2 and 2A. In this position shuttle outlet 32 is once again

aligned with first pump outlet port 21.

As cam ring 14 is further rotated in a clockwise direction, increasing wall

thickness segment 54 will once move urge piston 40 to the left causing fluid to be

expelled from chamber 26 and simultaneously aspirated into chamber 28. As the

cam ring 14 continues to rotate, it is apparent that the pumping cycle will continue

in the manner described in the preceding paragraphs.

Turning next to figure 6B, an alternate form of the pumping apparatus is

there shown. In this alternate form, the piston driving means is constructed and ar¬

ranged so that the shuttle 24 can be moved into the third position shown in figure

6B wherein outlet passageway 33 of the shuttle is in communication with inlet port

20 of the pump body and is also in communication with outlet port 21 of the pump

body. With the components of the device in this position, fluid can flow directly from the inlet port of body 16 to the outlet port via flow passageway 33 to enable

expeditious initial priming of the pump as may be necessary.

Referring finally to figure 7, still another embodiment of the apparatus of the

invention is there shown and generally identified by the numeral 60. This em¬

bodiment is similar in many respects to that shown in figures 1 tlirough 6 and once

again like numbers are used to identify like components. The principal difference

between this last form of the invention and those earlier described resides in the

provision of a different piston driving means for reciprocating piston 40. More

particularly, as shown in figure 7, the cam ring has been replaced by a pair of sole¬

noids 62 and 64. Solenoids 62 and 64 are of a conventional construction well

known to those skilled in the art and can be alternately energized to cause the re¬

ciprocating movement of piston 40 as indicated by the arrows 65 and 67. Using

the solenoids in this way, piston 40 and, in turn, shuttle 24 can be moved through

the pumping cycle as earlier discussed herein. It is to be noted that this alternate

piston driving means can be used to drive the piston in the various manners indi¬

cated in figures 1 through 6 as well as into the priming position shown in figure

6B. Additionally, it is to be understood that other types of mechanical and elec¬

tromechanical means well known to those skilled in the art can be used to appro¬

priately drive the piston 40. Having now described the invention in detail in accordance with the re¬

quirements of the patent statutes, those skilled in this art will have no difficulty in

making changes and modifications in the individual parts or tlieir relative assembly

in order to meet specific requirements or conditions. Such changes and modifica¬

tions may be made without departing from the scope and spirit of the invention as

set forth in the following claims.

Claims

I CLAIM:

I . An apparatus for moving fluid from a first location to a second loca¬

tion comprising:

(a) a body having a passageway and a fluid inlet and first and sec¬

ond fluid outlets in communication with said passageway, said fluid inlet

being in communication with said first location and said first and second

fluid outlets being in communication with said second location;

(b) a shuttle movable within said passageway of said body between

first and second position, said shuttle having first and second fluid chambers

and including:

(i) an outlet permitting fluid communication between said

first fluid chamber and said first fluid outlet port of said body when

said shuttle is in said first position;

(ii) an outlet permitting fluid between said second fluid

chamber and said second fluid outlet port of said body when said

shuttle is in said second position;

(iii) an inlet permitting fluid communication between said

second fluid chamber and said fluid inlet port of said body when said

shuttle is in said first position; and (iv) a fluid inlet permitting fluid communication between said

first fluid chamber and said fluid inlet port of said body when said

shuttle is in said second position; and

(c) a piston reciprocally movable within said shuttle between first

and second positions.

2. The apparatus as defined in claim 1 in which said piston moves said

shuttle between said first and second positions as said piston moves between said

first and second positions.

3. The apparatus as defined in claim 1 in which said piston has a first po¬

sition sealably movable within said first fluid chamber of said shuttle and a second

portion sealably movable within said second fluid chamber of said shuttle.

4. The apparatus as defined in claim 3 in which fluid is aspirated into

said second fluid chamber as said piston moves toward said second position.

5. The apparatus as defined in claim 3 in which said piston moves said

shuttle within said passageway of said body as said piston moves toward said sec¬

ond position.

6. The apparatus as defined in claim 3 in which fluid is aspirated into

said first fluid chamber as said piston moves from said second position toward said

first position.

7. The apparatus as defined in claim 3 in which fluid is expelled from

said first chamber of said shuttle as said piston moves toward said second position

and fluid is simultaneously aspirated into said second chamber of said shuttle as

said piston moves toward said second position.

8. The apparatus as defined in claim 3 in which fluid is expelled from

said second chamber of said shuttle as said piston moves from said second position

toward said first position and fluid is simultaneously aspirated into said first cham¬

ber of said shuttle as said piston moves from said second position toward said first

position.

9. The apparatus as defined in claim 3 further including means for mov¬

ing said piston between said first and second positions.

10. The apparatus as defined in claim 9 in which said means for moving

said piston between said first and second positions comprises a rotatable cam ring

11. The apparatus as defined in claim 9 in which said means for moving

said piston between said first and second pistons comprises a pair of solenoids.

12. An apparatus for moving fluid from a first location to a second loca¬

tion comprising:

(a) a body having a passageway and a fluid inlet and first and sec¬

ond fluid outlets in communication with said passageway, said fluid inlet 1236

being in communication with said first location and said first and second

fluid outlets being in communication with said second location;

(b) a shuttle movable within said passageway of said body between

first and second position, said shuttle having first and second fluid chambers

and including:

(i) an outlet permitting fluid communication between said

first fluid chamber and said first fluid outlet port of said body when

said shuttle is in said first position;

(ii) an outlet permitting fluid between said second fluid

chamber and said second fluid outlet port of said body when said

shuttle is in said second position;

(iii) an inlet permitting fluid communication between said

second fluid chamber and said fluid inlet port of said body when said

shuttle is in said first position; and

(iv) a fluid inlet permitting fluid communication between said

first fluid chamber and said fluid inlet port of said body when said

shuttle is in said second position;

(c) a piston reciprocally movable within said shuttle between first

and second positions, said piston moving said shuttle between said first and second positions as said piston moves between said first and second posi¬

tions; and

(d) means for moving said piston between said first and second po¬

sitions, said means comprising a cam ring.

13. The apparatus as defined in claim 12 in which said cam ring com¬

prises a generally ring shaped body having an inner surface said surface having

three circumferentially spaced piston engaging protuberances.

14. The apparatus as defined in claim 12 in which said piston has a first

position sealably movable within said first fluid chamber of said shuttle and a sec¬

ond portion sealably movable within said second fluid chamber of said shuttle.

15. The apparatus as defined in claim 14 in which fluid is aspirated into

said second fluid chamber as said piston moves toward said second position.

16. The apparatus as defined in claim 14 in which fluid is aspirated into

first position.

17. The apparatus as defined in claim 14 in which fluid is expelled from

said piston moves toward said second position.

18. The apparatus as defined in claim 14 in which fluid is expelled from

position.

19. A method for moving fluid from a first location to a second location

using an apparatus comprising a body having a central passageway and a fluid inlet

port and first and second fluid outlet ports in communication with the central pas¬

sageway, the fluid inlet port being in communication with the first location and the

first and second fluid outlet ports being in communication with the second loca¬

tion; a shuttle movable within the passageway of the body between first and second

positions, the shuttle having first and second chambers and including first and third

fluid passageways and first and second inlets and a piston reciprocally movable

within the shuttle; the method comprising the steps of:

(a) moving the piston within the first fluid chamber of the shuttle to

force fluid therefrom into the first fluid outlet port of the body via one of the

first and second passageways of the shuttle and to simultaneously cause fluid

to be aspirated into the second fluid chamber of the shuttle via the fluid inlet

port of the body and one of the first and second inlets of the shuttle; (b) moving the piston to move the shuttle from a first location

wherein the second inlet of the shuttle is in index with the fluid inlet port of

tlie body to a second location wherein the first inlet of the shuttle in is index

with the fluid inlet port of the body;

(c) moving the piston within the second fluid chamber of the shut¬

tle to force the fluid aspirated therein to flow from the second fluid chamber

into the second fluid outlet port of the body via the other of said first and

second passageways of the shuttle and simultaneously to cause fluid to be

aspirated into the first fluid chamber of the shuttle via the fluid inlet port of

the body and one of the first and second inlets of the shuttle; and

(d) moving the piston to move the shuttle from the second location

to the first location.

20. The method as defined in claim 19 in which the shuttle includes a

fourth fluid passageway and in which the method includes the step of moving the

shuttle to a third position wherein the first inlet port of the body is in communica¬

tion with one of the first and second outlet ports of the body via the fourth fluid

passageway.