U.S. patent number 3,858,750 [Application Number 05/431,277] was granted by the patent office on 1975-01-07 for pressure relief valve.
This patent grant is currently assigned to The Vollrath Co.. Invention is credited to Bernard C. Grall.
United States Patent |
3,858,750 |
Grall |
January 7, 1975 |
PRESSURE RELIEF VALVE
Abstract
A cooking pot cover has an opening in which a valve body is
vertically slideably and rotatably mounted. A flange on the bottom
of the valve body is engageable with the cover to limit the upward
movement of the valve body. A separately-formed valve cap is
snap-fitted from above into the top of the valve body and is
engageable with the cover to limit downward movement of the valve
body. A vent opening in a cylindrical portion of the valve body is
positioned to be above the cover when the valve body is in a raised
position and to be below the cover when the valve body is in its
lowermost position. Locking ribs project radially from the
cylindrical portion of the valve body and abut against the
underside of the cover to lock the valve body in its lowered
position when the valve body is in a predetermined position of
rotation. In another rotational position of the valve body, the
locking ribs are aligned with locking recesses in the margin of the
cover opening to permit upward movement of the valve body in
response to steam pressure to vent the steam out of the cooking
pot.
Inventors: |
Grall; Bernard C. (Sheboygan,
WI) |
Assignee: |
The Vollrath Co. (Sheboygan,
WI)
|
Family
ID: |
23711230 |
Appl.
No.: |
05/431,277 |
Filed: |
January 7, 1974 |
Current U.S.
Class: |
220/203.05;
D7/358 |
Current CPC
Class: |
A47J
36/06 (20130101); B65D 51/1644 (20130101) |
Current International
Class: |
A47J
36/06 (20060101); A47J 36/00 (20060101); B65D
51/16 (20060101); B65d 051/16 () |
Field of
Search: |
;220/44R,44A,44E
;137/532,533,533.17,533.31 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Petrakes; John
Attorney, Agent or Firm: Morsell, Jr.; Arthur L.
Claims
What I claim is:
1. In combination with a utensil cover having an opening therein, a
pressure relief valve body vertically slideably and rotatably
mounted within said opening; means on a lower portion of said valve
body engageable with said cover to limit the upward movement of
said valve body; a separately-formed valve cap for said valve body,
said cap having means engageable with the top of the cover to limit
the downward movement of the valve body; cooperating means on said
cap and valve body connecting the same in assembled relationship
while aligned with the cover opening and with the cover between at
least a portion of said valve body and cap, said valve body having
a vent opening positioned to be above said cover when said valve
body is in a raised position and positioned to be below said cover
when said valve body is in its lowered position; and cooperating
locking means on said valve body and cover to selectively lock said
valve body in its lowered position when the valve body is in one
position of rotation and to permit upward movement when the valve
body is in another position of rotation.
2. The combination claimed in claim 1 wherein said means on the
bottom of said valve body engageable with said cover to limit the
upward movement of said valve body comprises an outwardly-extending
flange at the lower end of said valve body, said flange extending
far enough outwardly from said valve body so that it will abut
against the bottom of said cover when the valve body is in a raised
position.
3. The combination claimed in claim 1 wherein said cooperating
means on said cap and valve body for connecting the same in
assembled relationship comprises an opening in the top of said
valve body having an inwardly-tapered marginal portion, a stem
projecting downwardly from said valve cap and having a
conically-tapered lower portion providing a shoulder, there being
relative resiliency between said tapered stem portion and the
marginal portion of the opening, and said tapered portion and
shoulder of said stem being positioned and sized to snap through
said tapered marginal portion of said opening in response to
pressure.
4. The combination claimed in claim 1 wherein said cooperating
locking means on said valve body and cover comprises at least one
locking rib projecting radially outwardly from said valve body, and
at least one cooperating recess in the margin of said cover
opening, said recess being large enough to receive said locking rib
when the rib is aligned with said recess to permit upward movement
of the valve member to venting position, and the upper end of said
locking rib being located adjacent the lower surface of said cover
when said locking rib is out of alignment with said recess to lock
the valve body in non-venting position.
5. The combination claimed in claim 4 and further comprising a
pointer on said valve so positioned relative to said locking rib as
to indicate the position thereof with respect to said recesses in
the margin of said cover opening.
6. The combination claimed in claim 1 and further comprising guide
means projecting downwardly from said valve cap and engageable with
matching guide means in the upper end of said valve body for
insuring proper rotational orientation between the valve cap and
valve body when the two parts are assembled.
7. The combination claimed in claim 1 in which said valve body is a
cylindrical sleeve having an outwardly-projecting annular flange at
the lower end thereof and having a top opening, the inner margin of
said opening being tapered, and further comprising a tapered stem
projecting from the bottom of said valve cap dimensioned to
interact with said tapered margin to provide for snap-fitting the
two parts together.
Description
BACKGROUND OF THE INVENTION
This invention relates to a pressure relief valve for cooking pots
or similar utensils.
One object of this invention is to provide a manually dialable
pressure relief valve for selectively venting steam from the cover
of a cooking pot.
Another object of this invention is to provide a pressure relief
valve of the above-described character which is simple in structure
and is easy to fabricate, assemble, and operate.
Other objects, advantages, and features of the invention will be
apparent to those skilled in the art from the description which
follows.
SUMMARY OF THE INVENTION
A pressure relief valve body is vertically slideably and rotatably
mounted in an opening in a utensil cover. Means on a lower portion
of the valve body is engageable with the cover to limit upward
movement of the valve body. A separately-formed valve cap is
snap-fitted from above into the valve body when the body is
inserted from beneath the cover. A vent opening in the valve body
is positioned to be above the cover when the valve body is in a
raised position and to be below the cover when the valve body is in
its lowered position. Cooperating locking means on the valve body
and cover selectively hold the valve body in its lowered position
when the valve body is in one rotational position and permit upward
movement of the valve body when it is in another rotational
position to vent steam through the vent opening.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged side elevational view, partially in vertical
section, of the pressure relief valve of this invention as its
component parts are being assembled on a utensil cover, a fragment
of the cover and utensil being shown.
FIG. 2 is a fragmentary top view of the utensil cover showing the
opening therein for receiving the valve body.
FIG. 3 is a side elevational view, partially cut away, of a utensil
having the pressure relief valve of FIGS. 1 and 2 installed on its
cover and in venting position.
FIG. 4 is a view similar to FIG. 1 showing the valve dialed to
locking position.
FIG. 5 is a top view looking in the direction indicated by the line
5--5 in FIG. 4.
FIG. 6 is an enlarged top view of the valve body alone before the
valve cap is attached thereto.
FIG. 7 is a cross-sectional view taken on the line 7--7 of FIG.
6.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The drawing shows one embodiment of the invention which is mounted
in an opening 10 (FIG. 2) in the cover 12 (FIG. 3) of a cooking pot
14. This embodiment includes a valve body 16 and a valve cap 18
which are snap-fitted together by means described hereinafter.
Valve body 16 is shaped in the form of a cylindrical sleeve having
an outer diameter which is slightly smaller than the opening 10 so
that valve body 16 will be vertically slideable and rotatable
therein. Two vertical locking ribs 20 (FIGS. 4 and 6) are formed on
the outside of the cylindrical portion of the valve body 16.
Locking ribs 20 are semi-cylindrical in cross section, and are
positioned diametrically opposite each other on the valve body 16.
A cooperating pair of semi-circular recesses 22 (FIG. 2) is formed
in diametrically-opposite locations in the margin of opening 10 to
receive the locking ribs 20 when the valve body 16 is in one
position of rotation (the position of FIG. 3). Thus the valve body
16 is movable up and down in opening 10 when the locking ribs 20
are aligned with recesses 22. However, in all other rotational
positions of valve body 16, the upper ends 24 of ribs 20 (FIGS. 4
and 7) abut against the underside of the utensil cover 12 and
prevent the valve body 16 from moving upwardly.
One or more vent openings 26 (FIGS. 3 and 7) are formed in valve
body 16 in such position as to be above the cover 12 when the valve
body 16 is in a raised position, as shown in FIG. 3, but to be
below cover 12 when the valve body 16 is in its lowered position.
Thus, when valve body 16 is in the dialed position of FIGS. 1 and 3
in which locking ribs 20 are aligned with recesses 22, steam
pressure in pot 14 will enter the interior of the cylindrical body
16 to push the valve body upwardly until vents 26 are above cover
12, thereby allowing the steam to escape from pot 14 through the
vents 26 and thus relieve the pressure within pot 14. Upward
movement of the valve body 16 is limited by a flange 28 (FIG. 4)
which is formed at the bottom of valve body 16 and which projects
outwardly therefrom so as to engage the under surface of the cover
12. When the valve body 16 is dialed to a rotational position such
as that of FIGS. 4 and 5 in which the locking ribs 20 are not
aligned with the recesses 22, the upper ends 24 of ribs 20 abut
against the underside of the cover 12 inwardly of the margin of the
opening 10 to lock the valve body 16 in closed position where steam
is confined within the pot.
One important feature of this invention is that the valve body 16
and the valve cap 18 can be easily assembled by simply snap-fitting
the two parts together. As a means of snap-fitting the valve cap 18
and valve body 16 together, the top of the valve body has an
opening 30 with an inwardly-tapering and rounded margin 32. The
opening 30 is dimensioned to yieldingly receive a cylindrical stem
34 having a conically-tapered lower portion 36 providing a shoulder
38 which is positioned so that it can be snapped beneath the margin
of the opening 30 to lock the cap 18 to the body member 16 (see
FIG. 1). This is accomplished by the simple expedient of pressing
the two parts together with the body 16 positioned beneath the pot
cover 12 and the cap 18 inserted from above the cover.
Cap 18 has a raised, tapered finger hold 40 (FIGS. 1 and 5) on its
upper surface to allow the cap 18 to be easily grasped for dialing.
The front end of the finger grip 40 is pointed at 42 to form an
indicator to show the orientation of the locking ribs 20. To insure
that the pointer 42 is aligned in assembly with the locking ribs
20, a pair of guide openings 44 (FIG. 6) are formed on the upper
surface of valve body 16 and are positioned to receive matching
guide bosses 46 (FIG. 1) when the valve cap 18 is press-fitted onto
the valve body 16.
The valve cap 18 and valve body 16 can be conveniently molded from
a suitable plastic material such as is available under the trade
name of "Zytel," or any other suitable plastic material such as
nylon. This type of material has sufficient resiliency to provide
for the snap-fit during assembly when the conical portion 36 of
stem 34 is snapped from the full line position of FIG. 1 to the
dotted line assembled position. It will be apparent to those
skilled in the art that the valve cap 18 and valve body 16 can be
mass produced at a very low cost by injection molding or similar
processes. Also, the opening 10 and semi-circular recesses 22 can
be easily made in the cover 12 at a very low cost.
In use of a cooking pot equipped with the improved pressure relief
valve, if the housewife is cooking something in the pot in such a
manner that there will be a pressure build-up, she merely dials the
valve to the position shown in FIGS. 1 and 3 where the ribs 20 are
aligned with the recesses 22. Then, as soon as pressure builds up,
the steam will act against the valve to move it to the elevated
position of FIG. 3. This brings the vents 26 above the surface of
the cover and allows the steam to freely escape. If, on the other
hand, the housewife is cooking vegetables or other food on a low
flame where excessive pressure build-up is not likely to occur,
then the valve can be dialed to the position of FIGS. 4 and 5 to
lock the valve in the lowered position. This precludes the escape
of steam from the valve but will speed up the cooking process and
improve the results for certain types of food items. Of course,
even when the valve is locked as in FIGS. 4 and 5, with the type of
cooking pot and cover illustrated, the cover can, of course, bobble
up and down to relieve excessive steam pressure, should this occur.
For most operations this is undesirable and, by having the valve
dialed to the position of FIGS. 1 and 3, pressure is relieved
without the objectionable bobbling of the cover which would
otherwise occur. The present relief valve enables the housewife to
select the type of steam control best suited for the item being
cooked.
Various changes and modifications may be made without departing
from the spirit of the invention, and all of such changes are
contemplated as may come within the scope of the claims.
* * * * *