U.S. patent number 3,561,648 [Application Number 04/814,571] was granted by the patent office on 1971-02-09 for resilient integral bodies incorporating poppet-valves.
Invention is credited to Frederick Harold Humphrey.
United States Patent |
3,561,648 |
Humphrey |
February 9, 1971 |
RESILIENT INTEGRAL BODIES INCORPORATING POPPET-VALVES
Abstract
The combination of a supporting surface having two ports, and an
integral body which includes a recess-defining resilient portion
secured against the surface to define therewith a chamber into
which the two ports open. A poppet-valve integral with the body
extends toward the surface and closes one port with mechanical
interference, thereby to establish one pressure threshold above
which fluid flows from one port to the other port, and a second
pressure threshold above which fluid flows in the opposite
direction.
Inventors: |
Humphrey; Frederick Harold
(Markham, Ontario, CA) |
Family
ID: |
25215461 |
Appl.
No.: |
04/814,571 |
Filed: |
April 9, 1969 |
Current U.S.
Class: |
222/207 |
Current CPC
Class: |
F16K
11/022 (20130101) |
Current International
Class: |
F16K
11/02 (20060101); B65d 037/00 () |
Field of
Search: |
;222/207 ;103/150 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Moorhead; Davis T.
Claims
I claim:
1. An integral body for use with a supporting surface through which
two apertures open, the body comprising:
a resilient portion defining a recess having sidewalls and a top
wall, the resilient portion being adapted to be placed against the
supporting surface such that the recess defines with the supporting
surface a main chamber into which the two apertures open;
and an integral poppet-valve extending from the top wall toward the
supporting surface and being adapted to close one aperture with
mechanical interference, the poppet-valve being centrally recessed
to define a subchamber in communication with said one aperture and
being outwardly flared where it contacts the supporting surface,
thereby to provide a first pressure threshold above which fluid
flows from said one aperture to the other aperture and a second
pressure threshold above which fluid flows from said other aperture
to said one aperture, said first pressure threshold being at least
partly a function of the amount of said mechanical interference and
at least partly a function of the area of the supporting surface
within said subchamber, said second pressure threshold being at
least partly a function of the area of the top wall surrounding the
poppet-valve.
2. The combination of a supporting surface through which two
apertures open, and an integral body, the integral body
comprising:
a resilient portion defining a recess having sidewalls and a top
wall, the resilient portion being secured against the supporting
surface such that the recess defines with the supporting surface a
main chamber into which the two apertures open;
an integral poppet-valve extending from the top wall toward the
supporting surface and adapted to close one aperture with
mechanical interference, the poppet-valve being centrally recessed
to define a subchamber in communication with said one aperture and
being outwardly flared where it contacts the supporting surface,
thereby to provide a first pressure threshold above which fluid
flows from said one aperture to the other aperture and a second
pressure threshold above which fluid flows from said other aperture
to said one aperture, said first pressure threshold being at least
partly a function of the amount of said mechanical interference and
at least partly a function of the area of the supporting surface
within said subchamber, said second pressure threshold being at
least partly a function of the area of the top wall surrounding the
poppet-valve.
3. An integral body as claimed in claim 1, in which an integral
partition extends from the top wall of the recess to terminate in
an edge adapted to rest resiliently against said supporting surface
at a location between said two apertures, thereby to divide the
main chamber into a first compartment containing said poppet-valve
and said one aperture and a second compartment containing said
other aperture, said partition being adapted to define an acute
angle with the supporting surface in the second compartment
adjacent said edge, the top wall within said first compartment
having a portion which is resiliently deformable whereby the volume
of said first compartment can be changed.
4. An integral body as claimed in claim 3, in which a further
integral partition extends from the top wall of the recess to
terminate in an edge adapted to rest resiliently against said
supporting surface at a location between said poppet-valve and said
resiliently deformable portion of the top wall, thereby to divide
the first compartment into a first subcompartment defined in part
by said resiliently deformable portion of the top wall, and a
second subcompartment containing said poppet-valve and said one
aperture, said further integral partition being adapted to define
an acute angle with the supporting surface in the first
subcompartment adjacent the edge of the further integral
partition.
5. An integral body as claimed in claim 1, in which the
poppet-valve is closer to one sidewall of the recess than to the
opposite sidewall, and in which the part of the poppet-valve
closest to said one sidewall has less mechanical interference with
the supporting surface than has the part closest to said opposite
sidewall.
6. The combination claimed in claim 2, in which an integral
partition extends from the top wall of the recess to terminate in
an edge adapted to rest resiliently against said supporting surface
at a location between said two apertures, thereby to divide the
main chamber into a first compartment containing said poppet-valve
and said one aperture and a second compartment containing said
other aperture, said partition defining an acute angle with the
supporting surface in the second compartment adjacent said edge,
the top wall within said first compartment having a portion which
is resiliently deformable whereby the volume of said first
7. The combination claimed in claim 6, in which a further integral
partition extends from the top wall of the recess to terminate in
an edge adapted to rest resiliently against said supporting surface
at a location between said poppet-valve and said resiliently
deformable portion of the top wall, thereby to divide the first
compartment into a first subcompartment defined in part by said
resiliently deformable portion of the top wall, and a second
subcompartment containing said poppet-valve and said one aperture,
said further integral partition being adapted to define an acute
angle with the supporting surface in the first subcompartment
adjacent the edge of the further integral partition.
8. The combination claimed in claim 2, in which the poppet-valve is
closer to one sidewall of the recess than to the opposite sidewall,
and in which the part of the poppet-valve closest to said one
sidewall has less mechanical interference with the supporting
surface than has the part closest to said opposite sidewall.
9. An integral body as claimed in claim 1, in which the integral
body is made of a material chosen from the group: plasticized PVC,
ethyl vinyl acetate, styrene-butadiene rubber, butyl rubber,
natural rubber, and silicone rubber.
10. An integral body as claimed in claim 3, in which the integral
body is made of a material chosen from the group: plasticized PVC,
ethyl vinyl acetate, styrene-butadiene rubber, butyl rubber,
natural rubber, and silicone rubber.
11. The combination claimed in claim 2, in which the integral body
is made of a material chosen from the group: plasticized PVC, ethyl
vinyl acetate, styrene-butadiene rubber, butyl rubber, natural
rubber, and silicone rubber.
12. The combination claimed in claim 6, in which the integral body
is made of a material chosen from the group: plasticized PVC, ethyl
vinyl acetate, styrene-butadiene rubber, butyl rubber, natural
rubber, and silicone rubber.
Description
This invention relates to resilient, elastomeric members which
incorporate a poppet-valve construction capable of establishing
certain pressure thresholds which determine fluid flow.
An object of a particular embodiment of this invention is to
provide an elastomeric pump which incorporates a poppet-valve
construction in such a way that, on the pumping stroke, the
poppet-valve permits fluid to be pumped only after a particular
pressure threshold has been surpassed. With such a construction,
the poppet-valve pump can be used with liquid dispensers
incorporating spray nozzles, with the advantage that the spray
characteristic during the pumping stroke is substantially constant.
Conventional spraying mechanisms which do not have such a pressure
threshold feature often have the disadvantage, overcome by this
invention, that the spray pattern deteriorates towards the end of
the pumping stroke due to a dropping off of the pressure behind the
fluid, often with the result that the spray coalesces at the end of
the stroke to form individual droplets which drip from the spray
nozzle. The formation of droplets also sometimes occurs at the
beginning of the pumping stroke as the pressure gradually builds
up.
Accordingly, this invention provides an integral body for use with
a supporting surface through which two apertures open, the body
comprising: a resilient portion defining a recess having sidewalls
and a top wall, the resilient portion being adapted to be placed
against the supporting surface such that the recess defines with
the supporting surface a main chamber into which the two apertures
open, and an integral poppet-valve extending from the top wall
toward the supporting surface and being adapted to close one
aperture with mechanical interference, whereby the pressure
threshold above which fluid flows from said one aperture to the
other aperture is at least partly a function of the amount of said
mechanical interference, and whereby the pressure threshold above
which fluid flows from said other aperture to said one aperture is
at least partly a function of the area of the top wall surrounding
the poppet-valve .
Four embodiments of this invention are shown in the accompanying
drawings, in which like numerals denote like parts throughout the
several views, and in which:
FIG. 1 is a cross-sectional view through a first embodiment of this
invention;
FIG. 2 is a cross-sectional view through a second embodiment of
this invention;
FIG. 3 is a cross-sectional view through a third embodiment of this
invention;
FIG. 4 is a perspective view, taken from beneath, of a fourth
embodiment of this invention; and
FIGS. 5, 6, 7 and 8 are cross-sectional views taken at four stages
in the operation of the fourth embodiment; and
FIG. 9 is a section taken at the line 9-9 in FIG. 4.
Turning first to FIG. 1, there is shown a base 10 exhibiting a
supporting surface 12 through which a first aperture 14 and a
second aperture 15 open. The first and second apertures 14 and 15
communicate with a first and a second tubular passageway 17 and 18
respectively.
Also shown in FIG. 1 is a generally circular integral body 20 which
comprises a resilient portion 22 defining a recess 24 having a
generally cylindrical sidewall 26 and a generally circular top wall
28. Thus, the recess 24 defines, with the supporting surface 12, a
main chamber 30 into which the two apertures 14 and 15 open. An
integral rim 34 is provided for securing the resilient portion 22
against the supporting surface 12.
Extending from the center of the top wall 28 toward the supporting
surface 12 is an integral poppet-valve 32 which is adapted to close
the second aperture 15 with mechanical interference, in such a way
as to establish a pressure threshold for the fluid at the aperture
15 above which fluid is permitted to flow from the second aperture
15 to the first aperture 14. Such a pressure threshold for the
fluid at the second aperture 15 presupposes that the fluid at the
first aperture 14 is atmospheric. If this is not the case, then a
more complicated "threshold" condition will have to be exceeded
before fluid flow takes place. Suppose that the pressure at
aperture 15 is greater than that at aperture 14 but that neither is
atmospheric. Then, the resultant force tending to lift the
poppet-valve 32 off the aperture 15 will equal the upward force due
to the pressure in the main chamber 30 acting upwardly on the top
wall 28, plus the upward force due to the fluid pressure in the
passageway 18, minus the downward force due to the pressure of the
atmosphere on the top wall 28. Given a constant atmospheric
pressure and a constant fluid pressure at aperture 14 (even though
different from atmospheric), the threshold condition for fluid flow
from aperture 15 to aperture 14 can again be given in terms of a
pressure at the aperture 15. In the appended claims, the expression
"pressure threshold" is intended to embrace both the simple and the
complex determination of the threshold conditions discussed
immediately above. It will further be appreciated that, regardless
of pressure conditions, the "pressure threshold" will always be at
least partly a function of (i.e., at least partly depend upon) the
amount of the mechanical interference between the poppet-valve 32
and the supporting surface 12.
A further pressure threshold is also established, and this one
governs the point at which fluid is permitted to flow from the
first aperture 14 to the second aperture 15 when the pressure in
the former is greater than that in the latter. Again, the complex
expression for this further pressure threshold would be given as
the upward force due to the pressure in the main chamber 30 acting
upwardly on the top wall 28, plus the upward force due to the fluid
pressure in the passageway 18, minus the downward force due to the
pressure of the atmosphere on the top wall 28. When the resultant
force upwardly is great enough to overcome the mechanical
interference between the supporting surface 12 and the poppet-valve
32, the latter will be lifted away from the former, and fluid will
flow from the first aperture 14 to the second aperture 15. As with
the first threshold condition discussed above, given a constant
atmospheric pressure and a constant fluid pressure at the aperture
15 (even though different from atmospheric), the threshold
condition for fluid flow from aperture 14 to aperture 15 can be
expressed in terms of a pressure at the aperture 14, which
determines the pressure acting upwardly against the top wall 28
adjacent the poppet-valve 32.
Thus, this further pressure threshold, above which fluid flows from
the aperture 14 to the aperture 15 through the main chamber 30, is
at least partly a function of the area of the top wall 28
surrounding the poppet-valve 32 within the main chamber 30, since
this area determines the upward force transmitted to the
poppet-valve 32.
Of course, the upward force tending to lift the poppet-valve 32 off
the supporting surface 12 as a result of the pressure in the main
chamber 30 cannot be computed merely by multiplying the pressure
within the main chamber 30 by the area of the top wall 28 within
the main chamber 30, because the sidewalls 26 are held in position
against the supporting surface 12 through the agency of the
integral rim 34 which is clamped, glued, welded or otherwise
fastened against the base plate 10. Nonetheless, the lifting force
on the poppet-valve 32 will be a function of the pressure within
the main chamber 30.
Referring now to FIG. 2, it will be seen that the second embodiment
differs from the first only in that the poppet-valve 36 has a
central recess 38 which defines a subchamber 40 in communication
with the second aperture 15. All of the remaining parts of the
assembly of FIG. 2 are identical with those in FIG. 1. These parts
have not been numbered, in order to avoid cluttering the FIG. with
numerals. It will be realized that, with the provision of the
subchamber 40, the threshold described first above, i.e. the one
governing fluid flow from the aperture 15 to the aperture 14, is at
least partly a function of the area of the supporting surface 12
within the subchamber 40, since upward force against the
poppet-valve 36 due to the pressure of fluid in the passageway 18
will be equal to the fluid pressure times the effective area within
the subchamber 40, the latter being the same as the area of the
supporting surface 12 within the subchamber 40.
In the third embodiment shown in FIG. 3, the poppet-valve 42 has a
central recess 44, and is outwardly flared at 45, as shown. The
outward flaring tends to increase the suddenness with which the
poppet-valve 42 moves from the closed to the open position when the
fluid pressure in the aperture 14 is above that in the aperture 15.
In most cases, an additional effect of the flare at 45 will likely
be to slightly raise the second of the two thresholds discussed
above, as well as increasing the suddenness of poppet-valve
opening. Again in FIG. 3, the remaining unnumbered portions of the
FIG. are identical with the like portions in FIGS. 1 and 2.
Although the integral bodies shown in FIGS. 1, 2 and 3 have been
assumed above to be circular in configuration, i.e. radially
symmetrical about a central axis, this configuration of course is
not essential. The poppet-valve, for example, need not be centrally
placed within the main chamber 30, nor does the main chamber 30
itself have to be circular in cross section. It should be pointed
out, however, that the position of the integral poppet-valve with
respect to the sidewall 26 will have some effect upon the two
thresholds described above. For example, if the poppet-valve is
immediately adjacent the sidewall 26, it is likely to require a
greater pressure differential across the top wall 28 to open the
valve, given the same mechanical interference between the valve and
the supporting surface 12.
Attention is now directed to FIGS. 4, 5, 6, 7, 8 and 9, all of
which depict the fourth embodiment of this invention. The fourth
embodiment is essentially a pump which incorporates a poppet-valve
such that, on the pumping stroke, the pressure must climb above a
particular threshold, determined by the poppet-valve, before fluid
actually is expelled through the outlet port.
Looking at FIGS. 4 to 9, an integral body 46 consists essentially
of a hollow, upstanding portion 48 and an elliptical surrounding
skirt 49. The skirt 49 consists of a top wall 50 and a sidewall 52.
At the bottom of the sidewall 52 is an integral peripheral rim 54,
which is adapted to be glued, clamped, or otherwise fastened
against a supporting surface 60 analogous to the supporting surface
12 shown in FIG. 1. To improve the seal between the rim 54 and the
supporting surface 12, the rim 54 is provided with two downwardly
protruding circumferential ribs 56 which, as can be seen in FIG. 9,
slope inwardly and are adapted to be compressed against the
supporting surface so that a "knife-edge" seal can be obtained
thereagainst.
Attention is now directed to FIG. 5, which is a vertical sectional
view taken on the major axis of the elliptical skirt 49 of the
integral body 46. The upstanding hollow portion 48 defines the
major part of a compartment 58. A first integral partition 59
extends from the top wall 50 of the skirt 49 toward the supporting
surface 60 of a base plate 61. As can be seen in FIG. 4, the
integral partition 59 extends across the width of the elliptical
skirt 49 and thus, when it is in contact with the supporting
surface 60, completely seals off the compartment 58 from a
poppet-valve compartment 63 on the other side of the integral
partition 59.
A further integral partition 65 extends from the top wall 50 on the
other side of the portion 48, and as can be seen in FIG. 4, the
further partition 65 also extends across the width of the
elliptical skirt 49. The further partition 65 thus divides the
compartment 58 from an intake compartment 66 on the side of the
partition 65 remote from the compartment 58.
As can be seen in FIG. 5, the base plate 61 has a first port 68 in
communication with the intake compartment 66, and a second port 70
in communication with the poppet-valve compartment 63. The ports 68
and 70 communicate with, respectively, tubular passageways 72 and
74.
As can be seen particularly in FIG. 5, both of the partitions 59
and 65 are in sloping relationship with the supporting surface 60,
such that they both slope toward the poppet-valve compartment 63.
As shown, the partitions 59 and 65 terminate in a knife-edge which
is adapted to rest resiliently against the supporting surface 60,
whereby fluid is capable of passing, for example, from compartment
58 into compartment 63 beneath the partition 59 provided that the
pressure in the compartment 58 exceeds that in the compartment 63
by a given amount determined by the force with which the partition
59 rests resiliently against the supporting surface 60. Fluid
cannot, however, flow from the compartment 63 to the compartment 59
beneath the partition 59 under ordinary circumstances, because the
pressure differential across the partition 59 (i.e. an excess of
pressure in compartment 63 over that in compartment 58) has the
effect of forcing the partition 59 more strongly against the
supporting surface 60, and therefore producing an even tighter seal
between the two compartments.
In the poppet-valve compartment 63 is a poppet-valve 75 which is
essentially the same shape as the poppet-valve 42 shown in FIG. 4.
As can be seen in FIG. 5, the poppet-valve 75 has a central recess
and flared edges. The central recess in the poppet-valve 75 is in
communication with the port 70.
Attention is now directed to FIGS. 6 and 7 which show an
intermediate stage and the final stage, respectively, in the
pumping stroke. The pumping stroke is carried out by deforming the
portion 48 in such a way as to reduce the volume of the compartment
58. Although this deformation can be carried out in several ways,
the method shown in the FIGS. is to press downwardly and sidewardly
against the top of the portion 48 as shown by the heavy arrows 76
in FIGS. 6 and 7. At the intermediate stage shown in FIG. 6, the
volume of the compartment 58 has decreased sufficiently to raise
the pressure differential across the partition 59 to the point
where the partition 59 is lifted away from the supporting surface
60 and fluid begins to flow into the compartment 63. When the stage
shown in FIG. 7 is reached, the volume of the compartment 58 has
decreased still further, and the pressure in the compartment 63,
now in full communication with the compartment 58, has risen to the
point where the resultant force exerted upwardly on the top wall 50
adjacent the poppet-valve 75 is enough to lift the poppet-valve off
the port 70. Once the poppet-valve 75 has been lifted away from the
port 70, the fluid in the compartment 53 flows outwardly along the
tubular passageway 74 as shown by the arrow 78.
During the pumping stroke shown in FIGS. 6 and 7, the pressure
differential across the partition 65 is in the direction which
forces the edge of the partition 65 more firmly against the
supporting surface 60, and therefore no transference of fluid
occurs from compartment 58 to compartment 66.
Attention is now directed to FIG. 8, which shows an intermediate
stage in the restoration of the portion 48 resiliently to its
normal position (which is that shown in FIG. 5). It is to be
understood that the portion 48 is restored automatically once the
downward pressure (the arrow 76) is removed. As the portion 48 is
springing back to its FIG. 5 position, the natural tendency of the
poppet-valve 75 will be to close once again over the port 70 and it
is shown in this position in FIG. 8. As well, the partition 59
again comes down to rest against the supporting surface 60, and
effectively seals the compartment 58 from the compartment 63. The
enlargement of the volume of the compartment 58, however, brings
about a pressure differential across the partition 65 which acts to
raise the partition 65 from the supporting surface 60, and permit
fluid to flow into the intake compartment 66 through the tubular
passageway 72, and thence into the compartment 58. In other words,
the pressure differential arises due to a lowering of the pressure
in compartment 58 below that in compartment 66. The arrow 80 shows
the ingress of fluid through the tubular passageway 72.
It is to be pointed out that, although the word "fluid" is used
above to describe the material pumped, thus including both gas and
liquid, the latter is the preferred substance to be pumped, because
of the superior seal created along the edges of the partitions 59
and 65. The pump is nevertheless capable of pumping a gas, such as
air, although perhaps with less efficiency, and in fact at the
beginning of a pumping sequence, with the compartments originally
filled with air, it will be necessary to perform several pumping
strokes to rid the compartments of air, and to draw through the
tubular passageway 72 sufficient liquid to fill up the compartments
58, 63 and 66.
It will further be appreciated that the partition 59 is not
strictly necessary for the adequate operation of the pump shown in
FIGS. 4 to 7. Because the poppet-valve 75 acts, in effect, like a
one-way valve, it will be possible to do away with the partition
59. Partition 59 has been here provided merely for the purpose of
increasing the efficiency of the one-way valve provided by the
poppet-valve 75.
It will further be appreciated that the precise positioning of the
poppet-valve 75 will have some effect on the forces which cause the
poppet-valve 75 to lift off the port 70. These forces are two in
number: the first of these is the force, described above which
arises due to the increased pressure in the compartment 63, and
which has the effect of lifting upwardly against the top wall 50 in
the compartment 63; the second of these forces relates to the
contortion of the resilient material of the integral body 46
itself, caused by the deformation of the portion 48. When the
portion 48 is pressed sideways and downwardly as shown in FIGS. 6
and 7, there naturally arises an upward force on the top wall 50 in
the compartment 63, and a corresponding downward force against the
top wall 50 in the compartment 66. This latter force could be
altered, of course, by deforming the portion 48 in a different way.
For example, should the portion 48 be pressed straight downwardly
toward the supporting surface 60, the forces on the top walls 50 of
the compartments 63 and 66 would likely be similar, but would
depend on the actual mode of deformation of the walls of the
portion 48. It will thus be appreciated that the force tending to
lift the poppet-valve 75 can be made less dependent upon a
deformation of the portion 58 and more dependent upon a pressure
buildup simply by moving the poppet-valve closer to the sidewall 52
and further away from the compartment 58. Also it is possible to
isolate the lifting force on the poppet-valve 75 entirely from the
forces arising through the deformation of the portion 48 simply by
redesigning the shape of the skirt 49 such that the compartment 63
is effectively isolated from the compartment 58, and such that
deformation of the portion 48 does not produce any forces of
significance in the top wall 50 of the compartment 63.
A number of materials are suitable for manufacturing the integral
body 20 of this invention. Generally speaking, most polymeric
substances which exhibit suitable elastic resilience, including
both natural and synthetic rubbers, would be satisfactory, barring
adverse reactions with the fluids passing through the integral
body. Specifically, from the wide field of suitable polymeric
materials exhibiting elastic resilience, the following have been
tested and found satisfactory as the material forming the integral
body 20:
Plasticized PVC
Ethyl vinyl acetate
Styrene-butadiene rubber
Butyl rubber
Natural rubber
Silicone rubber
Naturally, the choice of a material for any given application would
be governed not only by the solvent characteristics of the fluid
passing through the integral body 20, but also by economic
considerations and the performance criteria of the particular
application.
* * * * *