U.S. patent application number 09/885016 was filed with the patent office on 2001-12-27 for check valves.
Invention is credited to McFarland, Stanley.
Application Number | 20010054448 09/885016 |
Document ID | / |
Family ID | 9894072 |
Filed Date | 2001-12-27 |
United States Patent
Application |
20010054448 |
Kind Code |
A1 |
McFarland, Stanley |
December 27, 2001 |
Check valves
Abstract
A check valve comprises a body (10) of elastomeric material
having a tubular inlet (12) at a first end with a radial flange
(14). The body (10) has a side surround with three equi-spaced
valleys (16) tapering together towards a second end opposite to the
first end and having thereat sealing edges (22) in the form of a
triskelion. An openable mouth is extendible between said sealing
edges (22) of substantially the same areal dimensions as the
tubular inlet (12).
Inventors: |
McFarland, Stanley; (Bangor,
GB) |
Correspondence
Address: |
Ronald E. Greigg
GREIGG & GREIGG P.L.LC.
1423 Powhatan Street, Unit One
Alexandria
VA
22314
US
|
Family ID: |
9894072 |
Appl. No.: |
09/885016 |
Filed: |
June 21, 2001 |
Current U.S.
Class: |
137/849 |
Current CPC
Class: |
Y10T 137/7885 20150401;
F16K 15/147 20130101 |
Class at
Publication: |
137/849 |
International
Class: |
F16K 015/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 21, 2000 |
GB |
0015146.4 |
Claims
I claim:
1. A check valve comprising a body of elastomeric material having a
tubular inlet at a first end with a radial flange, the body having
a side surround with three equi-spaced valleys tapering together
towards a second end opposite to the first end and having thereat
sealing edges in the form of a triskelion, whereby an openable
mouth is extendible between said sealing edges of substantially the
same areal dimensions as the tubular inlet.
2. A check valve according to claim 1, wherein each arm of the
triskelion is of same length and has a slit substantially median of
its width.
3. A check valve according to claim 2, wherein the slits in the
arms unite together at adjacent ends.
4. A check valve according to claim 1, wherein the wall thickness
of the valley sides is greater than the wall thickness of the side
surround.
5. A check valve according to claim 1 or 4, wherein at the bottom
of each valley, a groove is positioned to provide a flexing
line.
6. A check valve according to claim 5, wherein the wall thickness
of the bottom of the groove is less than the wall thickness of the
valley sides.
7. A valve housing having one or more check valves according to any
one of claims 1 to 6.
Description
[0001] This invention relates to a check valve for use primarily,
but not essentially, in a toilet assembly particularly, but not
necessarily, of the type installed in land or water recreational
vehicles, for example motorhomes or boats respectively. A
requirement of such a check valve provided in an assembly is to
open to allow passage of waste material and thereafter to close to
prevent reentry of waste material or of any smell or gases deriving
from such waste material. It has been proposed heretofore that such
a check valve be a duckbill valve having a body of elastomeric
material having a tubular inlet portion at a first end with a
radial flange and a circumferential shoulder, the body having
opposed side walls tapering towards each other to terminate in
sealing edges at a second end, opposite to the first end, The
sealing edges lie in a plane diametrical of the tubular inlet
portion. A duckbill valve of this type is disclosed in U.S. Pat.
No. 5,063,619.
[0002] A problem with such duckbill valves is the limitations on
the quantity and diametrical size of material that can pass through
the mouth of the valve when open by deflection apart of the sealing
edges during a `flushing` operation.
[0003] An object of the present invention is to provide a check
valve in which such problem is obviated or mitigated.
[0004] Accordingly, the present invention is a check valve
comprising a body of elastomeric material having a tubular inlet at
a first end with a radial flange, the body having a side surround
with three equi-spaced valleys tapering towards a second end
opposite to the first end and having thereat sealing edges in the
form of a triskelion, whereby an openable mouth is extendible
between said sealing edges of substantially the same areal
dimensions as the tubular inlet.
[0005] Preferably, each arm of the triskelion is of same length and
has a slit substantially median of its width, and the slits in the
arms unite together at adjacent ends.
[0006] Preferably also, the wall thickness of the valley sides is
greater than the wall thickness of the side surround. At the bottom
of each valley, a groove is beneficially positioned to provide a
flexing line. The wall thickness of the bottom of the groove is
desirably less than the wall thickness of the valley sides.
[0007] An embodiment of the present invention will now be
described, by way of example, with reference to the accompanying
drawings, in which:
[0008] FIG. 1 is a first perspective view from above of a check
valve according to the present invention;
[0009] FIG. 2 is a second perspective view from below of the check
valve;
[0010] FIG. 3 is a plan view of the check valve;
[0011] FIG. 4 is a two-part sectional view of the check valve on
line IV-IV of FIG. 3: and
[0012] FIG. 5 is a side elevation view of the check valve and a
two-part valve housing (shown in cross-section) to which the valve
is fitted.
[0013] Referring to the drawings, a check valve comprises a body 10
of elastomeric material having a tubular inlet 12 at a first end
with a radial flange 14. The body 10 has a side surround with three
equi-spaced valleys 16 tapering together towards a second end
opposite to the first end. The remaining land portions 18 of the
side surround between the valleys 16 each circumferentially taper
towards said second end. The valleys 16 terminate in sealing edges
22 in the form of a triskelion, each arm 20 of which is of same
length and having a slit 24 median of its width, the slits 24
uniting together at adjacent ends. The wall thickness of the valley
sides is greater than the wall thickness of the side surround. A
flexing line 26 is provided by a groove 28 at the bottom of each
valley 16. The wall thickness of the bottom of the groove 28 is
less than the wall thickness of the valley sides.
[0014] In a use of the valve, as described hereinafter, to sustain
its shape and remain substantially axially rigid during a siphoning
or vacuuming cycle, during which back pressure may reach about 15
psi and regulations may require this to be increased by a factor of
2, the wall thickness of the valleys 16 is greater than the wall
thickness of the land portions 18 as above stated. For example, the
walls of the valleys 16 may be 2.50 mm compared to the walls of the
land portions 18 of 1.70 mm. The thickness of the wall of the
valley 16 at the flexing line 26 of the groove 28 may be 1.70
mm
[0015] The hardness of the elastomeric material may be between
80.degree.-90.degree. shore,
[0016] As shown in FIG. 5, one form of a valve housing is in two
parts 30, 32, the front side of the flange 14 abutting against the
end of part 32 and being clamped to form an airtight and watertight
seal when the two parts 30, 32 of the valve housing are screwed
together with the rear side of the flange 14 against the inside
ring 38 of the part 30, the second end of the valve extending into
the interior of part 32.
[0017] The part 32 is provided with reduced diameters and the
inside walls thereat are sloped at 34 to induce positive flow.
Also, the edge 36 of the part 32 at its outer end is
bevelled/champhered as shown.
[0018] In use, a check valve and valve housing as shown in FIG. 5
as described above is connected into a pipe of, for example, a
toilet assembly. The valve has an openable mouth extending between
said sealing edges 22 when opened to allow passage of material
through the opening of substantially the same areal dimensions as
the tubular inlet 12. The outflow pipe is provided with reduced
diameters and the inside walls thereat are sloped to induce a
positive flow. The valve housing may have more than one valve seat
to allow more than one check valve to be fitted.
[0019] Variations and modifications can be made without departing
from the scope of the invention described above and as described
hereinafter.
* * * * *