CA1039148A

CA1039148A - Relief valve

Info

Publication number: CA1039148A
Application number: CA259,629A
Authority: CA
Inventors: Thomas A. Novak
Original assignee: Eaton Corp
Current assignee: Eaton Corp
Priority date: 1975-09-05
Filing date: 1976-08-23
Publication date: 1978-09-26
Also published as: IT1064241B; JPS6224141Y2; FR2323077A1; DE2639571A1; JPS6181077U; JPS5233129A

Abstract

ABSTRACT OF THE DISCLOSURE
An improved pressure relief valve for tubelers tires or the like is provided. The pressure relief valve includes a novel poppet valve dust cover structure which will automatically reposition the dust cover after each opening or cycle of the relief valve and which will allow the dust cover to act as a secondary poppet valve surface during venting of the pressurized container in which the valve is mounted to increase the rate of fluid flow through the valve. The valve is designed to be sealingly mounted in an aperture in a wall of the pressurized container and may be mounted therein by means of a threaded connection, a clamp connection, a snap-in connection from the interior of the container or a push-in connection from the exterior of the container. The dust cover is attached to the main poppet valve member for axial movement therewith.

Description

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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.

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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.

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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 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 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 ~.
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. . 7 !1. 1 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 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.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A pressure relief valve comprising a body mountable to a pressurized container, said body defining an axially extend-ing passage therethrough having an inlet in fluid communication with the interior of the container and an outlet, said passage having a valve seat intermediate said inlet and said outlet, a poppet slidably mounted in said passage, said poppet having a surface biased to normally contact said valve seat to block the flow of fluid through said passage, and a cover member exterior of and coaxial with the outlet, said cover member generally rigidly mounted to said poppet for movement there-with, said cover member axially spaced from the surface of said poppet by a distance substantially equal to the separation of said valve seat and said outlet, said cover member having a cover surface relatively resiliently deformable for substan-tially sealing contact with the outlet.

2. A pressure relief valve comprising a body mount-able to a pressurized container, said body defining an axially extending passage therethrough having an inlet in fluid commun-ication with the interior of the container and an outlet, said passage having a valve seat intermediate said inlet and said outlet, a poppet slidably mounted in said passage, said poppet having a surface biased to normally contact said valve seat to block the flow of fluid through said passage, and a cover member exterior of and coaxial with the outlet, said cover mem-ber generally rigidly mounted to said poppet causing said cover member to move axially therewith and preventing relative axial movement therebetween, said cover member axially spaced from the surface of said poppet by a distance substantially equal to the separation of said valve seat and said outlet, said cover being formed of resilient material such that said cover member is axially flexible in the regions adjacent the outer periphery thereof.

3. The pressure relief valve of claim 2 wherein said body comprises an exterior rubber portion and an axially extend-ing hollow insert bonded to said exterior rubber portion, said passage comprising a larger diameter portion adjacent the outlet and a smaller diameter portion adjacent the inlet, said valve seat defined by the intersection of said larger and smaller diameter portions, said poppet slidably mounted in said larger diameter portion.

4. The valve of claim 3 wherein said poppet is biased towards said valve seat by a compressed spring extending between said poppet and a generally washer shaped spring seat axially fixed in said larger diameter portion of said passage adjacent the outlet, said stem extending through the central aperture in said washer shaped spring seat.

5. A pressure relief valve for maintaining the pressure within a pressurized container no greater than a predetermined maximum pressure, said valve comprising:
a valve body adapted to be sealingly mounted in an aperture in a wall of said pressurized container, said valve body having an axially extending passage therethrough, said passage having an inlet for fluid communication with the inter-ior of the pressurized container and an outlet for fluid com-munication with the exterior of the container, said passage defining a valve seat interposed between said inlet and said outlet;

an axially movable poppet member slidably received in said passage interposed between said valve seat and said outlet, said poppet member having a surface for sealing contact with said valve seat to prevent fluid flow through said passage;
means for biasing said poppet member toward said valve seat;
a valve stem extending from said poppet member towards said outlet, said stem attached to said poppet member for axial movement therewith; and a cover member exterior of said valve body and attached to said valve stem causing said cover member to move axially therewith and preventing relative axial movement therebetween, said cover member being sufficiently large to cover said outlet, said cover member being axially spaced from said poppet member such that said cover member will contact said outlet when the poppet member surface sealingly contacts said valve seat, said cover being formed of resilient material such that said cover member is axially flexible in the regions adjacent the outer periphery thereof.

6. The pressure relief valve of claim 1 wherein said cover member includes a cover surface for engagement with said outlet, said cover member being generally rigidly mounted to said stem to maintain said cover surface generally perpendicular to the axis of said passage.

7. The valve of claim 2 wherein said cover member is a substantially disc shaped device coaxial with and exterior to said passage.

8. The device of claim 2 wherein said stem is a multiple piece structure.

9. The device of claim 2 wherein said passage com-prises a larger diameter portion adjacent said outlet and a smaller diameter portion adjacent said inlet, said valve seat defined by the intersection of said larger and smaller diameter portions.

10. The valve of claim 5 wherein said biasing means is a spring, one end of said spring seated against the poppet member and the other end of said spring seated against a hollow spring seat fixed in said larger diameter portion adjacent the outlet, said stem passing through said hollow spring seat.

11. The valve of claim 6 wherein said spring seat com-prises a washer like member embedded in the larger diameter por-tion of said passage.

12. The valve of claim 6 wherein said valve body is adapted to be sealingly mounted in said aperture by insertion into said aperture from the exterior of said pressurized con-tainer.

13. The valve of claim 8 wherein said molded rubber body comprises a leading edge for insertion into the aperture, a tapered surface extending radially outwardly from the leading edge to a radially outwardly protruding shoulder and an annular groove defined between the shoulder and an enlarged bulbous flange on the end of the molded rubber body opposite the leading edge, said inlet being adjacent the leading edge and said outlet being adjacent the bulbous flange, said groove including an axially extending surface generally parallel to the axis of the passage and extending from the shoulder to the flange, said leading edge being of lesser outer diameter than the diameter of said aperture, said shoulder being of considerably larger outer diameter than the diameter of said aperture and said axially extending surface being of an outer diameter greater than the diameter of the shoulder and smaller than the outer diameter of the flange.

14. The valve of claim 9 wherein said valve body comprises an axially extending annular cavity between said insert and said molded rubber body adjacent said outlet, said cavity extending axially coincident with said shoulder and said groove.

15. The valve of claim 10 wherein said cavity is coax-ial with said insert, open to said flange and extends to a point axially interposed between said shoulder and said leading edge.

16. The valve of claim 11 wherein said insert is brass and includes a generally V-shaped depression on the exterior surface thereof adjacent said inlet.

17. The valve of claim 8 wherein said valve body is a snap-in valve body.