U.S. patent number 3,597,124 [Application Number 04/855,214] was granted by the patent office on 1971-08-03 for perastaltic pump.
This patent grant is currently assigned to Cenco Medical Health Supply Corporation. Invention is credited to Robert P. Adams.
United States Patent |
3,597,124 |
Adams |
August 3, 1971 |
PERASTALTIC PUMP
Abstract
A perastaltic pump having a plurality of rollers mounted on a
rotating pump wheel. Compressible tubing is supported by a tube
support means which is manually operable to move the tubing into
engagement with the rollers on the pumping wheel. Through the novel
shape of the tubing support means, the tube may be easily installed
and removed and functions to prevent tubing creep during
operation.
Inventors: |
Adams; Robert P. (Walden,
NY) |
Assignee: |
Cenco Medical Health Supply
Corporation (Chicago, IL)
|
Family
ID: |
25320633 |
Appl.
No.: |
04/855,214 |
Filed: |
September 4, 1969 |
Current U.S.
Class: |
417/477.11;
417/477.9; 417/12 |
Current CPC
Class: |
F04B
43/1284 (20130101) |
Current International
Class: |
F04B
43/12 (20060101); F04b 043/12 () |
Field of
Search: |
;103/149 ;230/168 ;91/57
;417/477,476 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Croyle; Carlton R.
Assistant Examiner: Goodlin; Wilbur J.
Claims
I claim:
1. In a perastaltic-type pump having a pump housing supporting a
pumping wheel, said pumping wheel having means for engagement with
a flexible tube through which material is pumped, the improvement
comprising a tube support means mounted on said housing for
movement toward and away from said pumping wheel, a tubing support
surface on said tube support means, said tubing support surface
being of generally U-shaped configuration to reverse the direction
of the tube thereon and thereby prevent tubing creep during
operation of said pump, said tube support surface including an
angular entrance portion merging into a substantially linear
section radially spaced from said pumping wheel, said linear
section merging with a generally U-shaped end portion leading into
a smooth arcuate portion adapted to be moved to a position closely
spaced from said pumping wheel and a generally linear portion
exiting from said arcuate portion.
2. The improvement is perastaltic-type pumps as defined in claim 1
wherein lug means is provided an opposition to each of said linear
sections, said lug means maintaining said tube in contact with said
linear sections to prevent tube creep during operation of said
pump.
Description
This invention relates to positive-type displacement pumps in
general and, more specifically, is directed to a new and improved
perastaltic pump of the type commonly used in biological,
medicinal, chemical, industrial, surgical, pathological and similar
type uses.
Perastaltic pumps, as such, are well known in the art and have
filled a definite need in the industry over the years where it is
desirable to isolate and control the flow through flexible tubing.
Since the tubing forms the path for the fluid pumped and is readily
removed, it may be autoclaved as a unit or fresh sterilized tubing
substituted when required for diverse uses or experiments.
One problem which has existed in the prior art is the difficulty
encountered in installation and removal of the tubing in prior art
designs. No doubt, this difficulty was a result of proposed
solutions to the problem of preventing tubing creep during the
pumping cycle. Various means have been proposed to eliminate these
problems, however, prior to the present invention, no solution has
been proposed which would offer a simple and satisfactory
answer.
The present invention provides a new and improved tube-mounting
arrangement in a perastaltic pump which permits the tubing to be
easily installed and removed while preventing tubing creep without
the use of complicated clamps or the like. A relatively simple
cam-biased tube support is mounted for angular movement to
disengage the tubing from the rollers carried on the pump wheel and
permits lateral removal and installation. The cam permits the
pressure on the tubing to be adjusted to the requirements of the
tubing used.
It is an object of this invention to provide a new and improved
perastaltic pump.
It is a further object of this invention to provide a new and
improved tube-mounting arrangement for a perastaltic pump which
permits removal and installation of the tubing with unequalled
ease.
It is a still further object of this invention to provide a new and
improved perastaltic pump having a simplified cam-biased tubing
support means which prevents tubing creep during the pumping
operation.
Objects in addition to those heretofore stated will appear from the
following description made in reference to the accompanying
drawings wherein:
FIG. 1 is a front elevational view of the perastaltic pump of the
present invention with the tubing in position for pumping;
FIG. 2 is a view similar to FIG. 1 with the tubing removed;
FIG. 3 is an enlarged fragmentary elevational view with the pumping
wheel broken away to show the cooperation of the rollers with the
tubing and tubing support means;
FIG. 4 is a fragmentary side elevational view taken generally along
the line 4-4 of FIG. 1;
FIG. 5 is a fragmentary side elevational view taken generally along
the line 5-5 of FIG. 1;
FIG. 6 is a free body front elevational view of the tubing support
means; and
FIG. 7 is a cross-sectional view taken generally along the line 7-7
of FIG. 6.
Referring now to FIG. 1, reference numeral 10 indicates the
perastaltic pump of the present invention including a pump housing
11 and front cover 12 which mounts a tubing support means indicated
generally at 13 and a pumping wheel indicated generally at 14. The
cover 12 also forms a mounting area for a switch 17 for turning the
pump on and off and which may also have an indicator light 18
included in the circuit for visually detecting the condition of the
pump.
A tube 15 is wrapped around the tubing support means 13 in a manner
to be described in greater detail in connection with FIGS. 3 and 6.
A manually operated cam means 16 is mounted at the lower end of the
housing 12 and cooperates with the tubing support means in a manner
to become apparent.
Referring now to FIGS. 3--5, it can be seen that the pump wheel 14
includes spaced-apart plates 20 and 21 held on a shaft 19 and
mounting a plurality of rollers 23 for rotation about individual
shafts 24. As the pumping wheel 14 rotates, the rollers 23 are
brought into engagement with the tubing 15, compressing it in a
manner similar to that shown in FIGS. 1 and 3 and forcing the
liquid through the tube 15. This function will be described in
greater detail when the operation of the pump is given.
Referring now to FIG. 6, it can be seen that the tube support means
13 includes a tube-mounting portion 30 which may be formed with a
shallow groove 31 which may be generally arcuate in cross section,
conforming generally to the shape of the tubing to be supported.
When viewed along its length, the groove 31 extends at an angle 32
to a point where the tube-supporting surface is generally
tangential to, however, spaced from the path generated by pumping
wheel 14. The tangential portion 33 merges with a smooth arcuate
tube-reversing portion 34 which changes the direction of the tube
support slightly in excess of 180.degree.. The tubing 15 then
enters the arcuate portion 34 formed on a radius of curvature
substantially congruent to the path traced by the rollers 23 at
their outer extremity. The arcuate portion 34 terminates smoothly,
merging into a straight or linear section 35 for leading the tube
15 away from the pumping area to the discharge area where the flow
is directed. Retaining lugs 36 and 37 cooperate with the straight
or linear mounting sections 33 and 35, respectively, to maintain
the tube 15 positioned in the groove 31 on the tube-mounting
means.
As shown in FIGS. 3 and 7, an elastomeric pad 38 may line at least
a part of the arcuate groove 34 to back the tube 15 in the area
where the rollers 23 are actively squeezing the tube to perform the
pumping function. The tube support means 13 is mounted for pivoting
movement on the face 12 of the pump housing 11 through a bearing
bolt 40 or the equivalent.
As best seen in FIGS. 1--3, the cam means 16 consists of a knoblike
member 41 mounted through a pivot pin 44 and having a handle 42
which extends well outwardly of the housing cover 12 for ease of
operation by the lab assistant or technician. The knob 41 is
provided with a slow rise cam surface 43 and flat side 46. As the
handle 42 is manually rotated, the cam surface 43 engages a
cooperating or follower surface 45 on the tube support means 13 to
move the tube support means about the pivot 40 and bring the tube
15 into engagement with the rollers 23. As shown in FIG. 2, when
the cam is rotated to a position where the flat side 46 opposes the
cam follower 45, the tube support means moves to the condition
shown to facilitate easy removal and installation of the tube.
Operation of the perastaltic pump of the present invention is
easily accomplished. A tube partially filled with a liquid is
placed on the tube support means 13. The cam means 16 is rotated to
bring the tube support and installed tubing 15 into engagement with
the rollers 23 as shown in FIGS. 1 and 3--5. The pumping wheel 14
may then be turned on via switch 17 for rotation or, if desired,
the pumping wheel 14 can be started in advance of moving the tubing
into engagement with the rollers 23. Pumping of the liquid will
continue so long as a fluid supply is available at the intake.
If desired, the pumping rollers 23 may be increased in overall
length and multiple tracks provided on a single tubing support
means of the same shape as that shown with the grooves supporting
the tubing being parallel to each other. In this manner, uniform
engagement of the tubing and rollers is assured for uniform
pumping. This is especially helpful in those situations where the
liquid is to be withdrawn while another is to be added at an equal
rate. Through the use of a tubing support means of the type
described herein, the tubing may be readily installed and removed,
eliminating the need for special clamps and the like. Tubing creep
is positively prevented without any need to constrict the tubing.
Lateral stability is provided by the elastomeric pad 38 in the
pumping region. The simplified design provides for a relatively
inexpensive pump which is capable of extremely high performance
characteristics. In the present design, a motor available on the
open market having a mechanical brake is used to permit
microvolumes to be pumped at desired intervals when coupled to a
suitable timer.
Upon a consideration of the foregoing, it will become obvious to
those skilled in the art that various modifications may be made
without departing from the invention embodied herein.
* * * * *