Note: Descriptions are shown in the official language in which they were submitted.
ll I
75-53
I¦ B~CKG~OUND OP THB IN~r~TIo~
I! This invention relates to pressure relief valves
¦¦ and more particularly relates to pressure relief valves for
l tubeless tires or the like having dust covers.
I
DESCRIPTIO~ OF THE PRIO~ AR~
Pressure relief valves for venting pressurized
containers, such as tubeless tires, to control the r,laximum
pressure therein are well known in the prior art. ~xamples
of such valves may be seen by rcference to United States Patcnts~
Nos. 1,772,107; 2,587,~73 and ~ 5~,G33.
The earlier prior art pressure relief valves were
not totally satisfactory as they tended to close or become
only partially open when pressure within the container approache¦
the predetermined ma~imum pressure which decreased the rate
of fluid flow through the valve thus slowing the venting operation
and/or they tended to become clogged and~or inoperative with
mud, moisture and/or dust.
Later prior art press~re relief valves utilizcd
dust covers to prevent clogging of the ~7alves with mud and/o~
20 ¦ dust and also for preventing moisture from entering the valve.
The dust covers utilized were not totally satisfactoly as the~r
were rubber flaps which tended to be easily dislodged and
required manual resetting andfor were plugs that were blown
off the valve when the valve was open.
'I The prior art valves were also less than totally
satisfactory as they were mounted in an aperture in a wall of
the contailler, such ~s an aperture in a tubeless tire rim, by
i, ;
mcans of threaded clam~in~ or bcin~ snapped-in from thc interior
1, of the container. S~1ch prior art mountin~ m~ethods may be
¦¦ draw~ac~.s dS they may be time consumin~ an~ e;:E~ensive .
In accordance with the present invention many of
the drawbacks of the prior art have been overcome by the pro-
vision of a pressure relief valve which includes a dust cover
automatically repositioned after each relief cycle and which
acts as a secondary poppet valve surface when the valve is
open to maintain the valve open for more rapid venting of
an over pressurized container. The valve may be convention-
ally sealingly mounted in an perture in the wall of the con-
tainer or may be pushed in from the exterior of the container.
According to one aspect of the invention there is
provided a pressure relief valve including a body mountable
to a pressurized container, the body defining an axially
extending passage therethrough having an inlet in fluid
communication with the interior of the container and an
outlet, the passage having a valve seat intermediate the
inlet and outlet~ The poppet is slidably mounted in the
passage, the poppet having a surface biased to normally
contact the valve seat to block the flow of fluid through
the passage. A cover member is provided exterior of and
coaxial with the outlet, and it is generally rigidly mounted
to the poppet for movement therewith. The cover member has
a cover surface relatively resiliently deformable for
substantially sealing contact with the outlet and is axially
spaced from the surface of the poppet by a distance substan-
tially equal to the separation of the valve seat and the
outlet.
'rhe valve body may include conventional mounting
means or may include means allowing the body to be sealingly
mounted in the aperture by insertion into the aperture from
the exterior of the container.
~b/ - 2 -
~t~3'3.~ 3
`11 ~ . . I
Accordingly, it is an object of the present inven-
tion to provide a new and improved pressure relief valve having
an improved dust cover.
Another object of the present invention is to
~ provide a new and improved pressure relief valve having an im-
¦ proved dust cover which will be automatically repositioned
¦ after each opening of the valve ana tThich will tend to retain
the valve in the open position when greater than predetermined
maximum pressure is in the container in which the valve is
mounted for more rapid venting thereof.
A further object of the present invention is to
provide a new and improved pressu_e relief valve having an
improved dust cover and an improved valve body allowing the
valve to be sealingly mounted in an aperture in the wall of
a pressurized container by insertion from the exterior thereof.
These and other objects and advantages oL the
present invention will become apparent from a reading of the
detaiied description of the preferred embodiment taken in
connection with the attached drawings.
~20 BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a front elevatior.al view in section
of one embodiment of the present invention.
FIGURE 2 is a front elevational view in section
of the pressure relief valve of FIGURE 1 as mounted in an
~25 ~ aperture in a tubeless tire rim or the li~e.
,I FIGURE 3 is a front elevational view in section
, of the valve of FIGURE 2 in the open or venting condition.
1~ . I
!! F
~l ~
~ 75-53
.,, . I
FIGURE 4 is a front elevational view in section
i of the valve of the present invention in the embodiment of
a snap-in valve.
j; FIGURE 5 is a front elevational view in section
~l of the valve of the present inveniion in the embodiment of a
I! clamp-invalve. I
¦¦ DESCRIPTION OF THE PREFERRED E~BODI~5ENT
The improved pressure relief valve 10 of the
I present invention may be seen by reference to the FIGURES. The
valve 10 is designed to be sealingly mounted in an aperture 14
in the wall 12 of a ~ressurized container as is illustrated
in FIGTJRES 2 and 3.
¦ The valve 10 is designed to open and allo~ pres-
¦~ surized fluid to flow out of the pressurized interior of the
container when the pressure in the container exceeds a pre-
determined maximum. The valve 10 is designed to close when
the interior of the container is at a pressure equal to or less
than the predetermined maximum pressure. For purposes of
illustration, the valve 10 will be discussed in terms of z.n
automotive tire pressure relief val~e mounted in an aperture
in a tubeless tire rim to control the maximum pressure in said
tire. It is undexstood that the pressure relief v~lve of the
present invention is suitable for uses ~ith various pressurized
l! containers other than tubeless tires and the li~e.
The valve 10 comprises a valve body 20 designed
I to be sealingly mounted in an aperture 14 in the wall or rim
12 of a pressurized container such as a tubeless tire rim or
the li~e. The valve body 20 is designed for mounting fro~ the
~ exterior of the containe;^ by forcible inse,tion of the valve
l' body 20 into the aperture 14 as will ~e described in detail t
! !
` ~ 73-53
3~:~4~ 1
¦ below. It is understood that the pressure relief valve of the
, present invention may also be sealin~ly mounted in an apexture
I by threaded clamping such as is seen in United States Patent
Il No. 2,744,~59; by bcing snapped-in from the interior of the
,, container such as is seen in United States Patent No. 2,818,101
¦l or other commonly used valve mountin~ techniques. E~c~n?les
¦ of such snap-in or clampin~ embodiments are illustrated in
¦ FIGURES 4 and 5 respectively.
j The valve body 20 illustrated is preferably of
I rubber or of an equivalent flexible elastic material. A
¦I hollow insert 40 is secured within the body 20 by known means,
¦ such as bonding. The hollow insert is preferably of a metal,
such as steel or brass, which adheres to rubber. The relief
valve insides, or core 60, is received within the valve insert
1 40.
¦¦ The valve body cor,prises a lower end 22 for
insertion into the aperture 14 in the wall 12 of the pressurized,
container which is radially outwardly tapered as at 24. The
texms upper, lower, top, bottom, etc., are used for illustra-
tive purposes and refer to the drawings. The terms are not
intended to be limiting upon the scope of the present invention. !
The tapered portion 24 extends upwardly from the leading edge
23 to a first shoulder 26, which in combination with the en-
. I larged bulbulous upper flange 28 defines a groove 30 there- I
ll between. The leading edse 23 of the lower end 22 of the valve
body is of a smaller diameter than the aperture 14 while the
first shoulder 26 is of a substantially larger diameter than
the aperture 14. The groove 30 includes an axially extending,
, annular bottom wall 32 e~tending betweell shoulder 26 and flanqe
28 which is of a diameter somewhat lar~er ~han the dic~meter of
the aperture 14 in which the valve 10 is to be sealingly mounted
but somewhat smaller diameter than the outer diameter of shoulder
I . . ,i
I -5- -r
Ll
73-53
26 or flange 28. An axially extending annular cavity 34
I separatcs the val~e bod~ 20 from the valve insert 40 axially
¦ coincident with the groove 30 and the shoulder 26 allowing thc
Il valve body to be radially inwardly deformed for mounting pur-
i poses. Axial stretching of the shoulder 26 during the instal-
lation also results in a smaller diameter of the shoulder
making the shoulder easier to force into the aperture.
As may be seer. from FIGURES 1 and 2, when the
valve body 20 is forcibly inserted, leading edge 23 of lowe~ ¦
end 22 first, into the aperture 14, the sides of the wall
defining the aperture will engzge the tapered portion 24 and
then the first shoulder 26, causing the valve body to inwardly 7
deform into cavity 34 as the tapered portion 24 and then the
shoulder 26 pass thro~gh the aperture 14 until the walls defin-
ing the aperture 14 are snapped-into the groove 30. The valve
lC ~s _calinsl~ m^unted in ap~rture 14 may be seen ~v reference
to FIGURE 2. q'he bulbulous flange 28 is of such diameter to
prevent passage thereof through the aperture and generaliy
radially extending, annular surface 29 will define the maximum
axiai penetration of the valve body 20 into the aperture 14.
The hollow ~alve insert 40 defines an axially
extending passage 42 through the valve 10. In .the moun'ed posi-
tion of t~e valve 10, the passage 42 extends from the intericr
~ to the exterior of the pressurized container. The insert may
,~ include various e~terior configurations suc~ as V-shaped slot
! 44 for enhancing the bondin~ retention between ~he valve body
and the insert. The passage 42 inc udes a smaller diameter
portion 46 at the lower ~r interior end thereof and a larser
diameter portion ~8 at the upper or exterior end thercof which
meet at a shoulder 50 which defines a valve seat. Tl-e passage
--6--
73-53
1~ 42 includcs an inlet 52 at the outcr end of the smaller diamcter
¦~ portion 46 and an outlet 54 at outer opening to the larger
, diameter portion 48.
Il Slidably received within the larger diameter portion
'. 48 of passage 42 is poppet valve member 62 which carries a
seal membcr ~4 for sealing engagement with the valve seat 50
¦. to block fluid flow through the passage 42. The poppet valve
member 62 is the form of a generally cylindrical member which
li is of smaller diameter than the larger diameter portion 48 of
¦¦ passage 42 allo~7ing fluid to flo~ around the poppet member 62
1~ and out of the outlet 54 when the seal 64 is not in sealing
¦¦ contact with the valve seat 50.
Il Located in and axially fixed to the passage 42
il adjacent the outlet 54 is a hollow, washer type member 70 which
1'l acts as a spring seat for the coil spring 72 which acts on the
1~ upper end of poppet ~.lve member 62 to bias the poppet val~re
.Ij member towards the valve seat 50. Spring seat 70 could, of
¦I course, be threadably engaged to the insert 40 for selecti~ely
~¦ adjusting the biasing force applied by spring 72 to poppet
~0 ~I valve member 62. The spring constant of compressed spring 72
Il is selected to supply a force to the poppet valve member equal
¦I to the predetermined maximum pressure in the container actin~
!i on the exposed surface of the sealing member 64.
!I The above defined poppet valve and valve seat
structure is known in the art and other functionally equivalent
` structures may be substituted therefor.
. Extending through the opening in the spring seat
member 70 is an axially extending stem 80 which extends from
the poppet 62 to the dirt, dust and/or moisture seal/cover 82.
The seal/co~er 82 is a generally annular disc which is of
sufficient diamcter to cover the opening 5~ to the passa~e ~.
.
. . 7
!1. 1
73-53
The scal/covcr may be of a metal, plastic, rubber or a combilla-
!~ tion thereof. The material selectcd should be som~what deform-
a~le to provide a good sealing contact between the seal/cover
1 and the outlet 54 to prevent the entry of mud, dirt, dust and/or
5 ll moisture into the relief valve. The seal/cover 82 is coaxial
with and exterior to the larger diameter portion 48 of passage
42.
The axially extending stem 80 may be of two or
! more portions, such as 84 and 86, to compensate for slight mis-
j alig.~ments and the like. The stem 80 relatively rigidly axially j
! connects the poppet 62 with the dust seal/cover 82 for jcintaxial movement. Th~ seal/cover 82 is axially spaced from the 1,
seal 64 such that the seal/cover 82 will enyage the outlet 54
Il when the seal 64 engages the valve seat 50. The stem 8~ may
15 ¦¦ be permanently or adjustably mounted to the poppet member 62
and tlle seal/cover 82 by various ~nowr. m~ns.
In operation, the relief valve and seal/cover
structure of the present invention provides two advantages over
the known prior art.
1 The seal/cover is coaxial with passage 42 and
outlet 54 and will move in axial unison with the poppet 64 and
will thus automatically be repositloned iII sealing contact ~ith
the outlet 54 when the poppet valve member seal 64 enga~es
¦¦ valve seat 50 closing the pressure relief valve 10. The seal/
~I cover will also automatically uncover outlet 54 when the poppet
valve member 62 moves axially away from seat 50 to allow f'uid
flot~ through the valveO
l~en pressu_e within the pressurized container
is sufficient to move the poppet valve me~er 62 upward asainst
thc force of sprin~ 72 to open the valve (see FIGURE 3), air
entering the inlet 52, escaping past thc va]~e seat ~0, around
the poppet mem~cr 62 and out of the ourlet 54 will tend to
pin.~e on or ac. agaînst the ]o~cr su~face &4 of thc scal/c,o~cr
I1 73-53
il
82. It is not~d that thc lower surf~ce ~4 of seal/co~er 82
will remain generally perpendicular to the axis of the poppct
Il valve member 62 by virtue of the relatively rigid connection
!I between stem 80 and seal/cover 82. The force of the escaping
~j pressurized air will create a force on the poppet member 62
j~ which will be additive with the force of pressurized fluid
¦ on seal 64 to move the poppet against the bias of spring 72.
The additive force of escaping pressurized alr acting on the
¦ under surface 84 of seal/cover 82 which will tend to retain
¦ the valve 10 in the fully open condition for rapid venting of
¦ the pressurized container.
Although this invention has been described in its
preferred form with a certain degree of partlcularity t is
I unders.ood that the present disclosure has been made only by
5 I way of example and that various changes in the details of
construction and combination and arrangement of the parts may
j be resorted to wi~hout depârtir.y from the spirit and the S_Op2 ',
¦ of the invention as hereinafter claimed.
_g_
~.
'
Il . . j
,~ , ' '~
